/** * attrib.c - Attribute handling code. Originated from the Linux-NTFS project. * * Copyright (c) 2000-2010 Anton Altaparmakov * Copyright (c) 2002-2005 Richard Russon * Copyright (c) 2002-2008 Szabolcs Szakacsits * Copyright (c) 2004-2007 Yura Pakhuchiy * Copyright (c) 2007-2010 Jean-Pierre Andre * Copyright (c) 2010 Erik Larsson * * This program/include file is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as published * by the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program/include file is distributed in the hope that it will be * useful, but WITHOUT ANY WARRANTY; without even the implied warranty * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program (in the main directory of the NTFS-3G * distribution in the file COPYING); if not, write to the Free Software * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #ifdef HAVE_STDIO_H #include #endif #ifdef HAVE_STRING_H #include #endif #ifdef HAVE_STDLIB_H #include #endif #ifdef HAVE_ERRNO_H #include #endif #ifdef HAVE_LIMITS_H #include #endif #include "param.h" #include "compat.h" #include "attrib.h" #include "attrlist.h" #include "device.h" #include "mft.h" #include "debug.h" #include "mst.h" #include "volume.h" #include "types.h" #include "layout.h" #include "inode.h" #include "runlist.h" #include "lcnalloc.h" #include "dir.h" #include "compress.h" #include "bitmap.h" #include "logging.h" #include "misc.h" #include "efs.h" ntfschar AT_UNNAMED[] = { const_cpu_to_le16('\0') }; ntfschar STREAM_SDS[] = { const_cpu_to_le16('$'), const_cpu_to_le16('S'), const_cpu_to_le16('D'), const_cpu_to_le16('S'), const_cpu_to_le16('\0') }; ntfschar TXF_DATA[] = { const_cpu_to_le16('$'), const_cpu_to_le16('T'), const_cpu_to_le16('X'), const_cpu_to_le16('F'), const_cpu_to_le16('_'), const_cpu_to_le16('D'), const_cpu_to_le16('A'), const_cpu_to_le16('T'), const_cpu_to_le16('A'), const_cpu_to_le16('\0') }; static int NAttrFlag(ntfs_attr *na, FILE_ATTR_FLAGS flag) { if (na->type == AT_DATA && na->name == AT_UNNAMED) return (na->ni->flags & flag); return 0; } static void NAttrSetFlag(ntfs_attr *na, FILE_ATTR_FLAGS flag) { if (na->type == AT_DATA && na->name == AT_UNNAMED) na->ni->flags |= flag; else ntfs_log_trace("Denied setting flag %d for not unnamed data " "attribute\n", flag); } static void NAttrClearFlag(ntfs_attr *na, FILE_ATTR_FLAGS flag) { if (na->type == AT_DATA && na->name == AT_UNNAMED) na->ni->flags &= ~flag; } #define GenNAttrIno(func_name, flag) \ int NAttr##func_name(ntfs_attr *na) { return NAttrFlag (na, flag); } \ void NAttrSet##func_name(ntfs_attr *na) { NAttrSetFlag (na, flag); } \ void NAttrClear##func_name(ntfs_attr *na){ NAttrClearFlag(na, flag); } GenNAttrIno(Compressed, FILE_ATTR_COMPRESSED) GenNAttrIno(Encrypted, FILE_ATTR_ENCRYPTED) GenNAttrIno(Sparse, FILE_ATTR_SPARSE_FILE) /** * ntfs_get_attribute_value_length - Find the length of an attribute * @a: * * Description... * * Returns: */ s64 ntfs_get_attribute_value_length(const ATTR_RECORD *a) { if (!a) { errno = EINVAL; return 0; } errno = 0; if (a->non_resident) return sle64_to_cpu(a->data_size); return (s64)le32_to_cpu(a->value_length); } /** * ntfs_get_attribute_value - Get a copy of an attribute * @vol: * @a: * @b: * * Description... * * Returns: */ s64 ntfs_get_attribute_value(const ntfs_volume *vol, const ATTR_RECORD *a, u8 *b) { runlist *rl; s64 total, r; int i; /* Sanity checks. */ if (!vol || !a || !b) { errno = EINVAL; return 0; } /* Complex attribute? */ /* * Ignore the flags in case they are not zero for an attribute list * attribute. Windows does not complain about invalid flags and chkdsk * does not detect or fix them so we need to cope with it, too. */ if (a->type != AT_ATTRIBUTE_LIST && a->flags) { ntfs_log_error("Non-zero (%04x) attribute flags. Cannot handle " "this yet.\n", le16_to_cpu(a->flags)); errno = EOPNOTSUPP; return 0; } if (!a->non_resident) { /* Attribute is resident. */ /* Sanity check. */ if (le32_to_cpu(a->value_length) + le16_to_cpu(a->value_offset) > le32_to_cpu(a->length)) { return 0; } memcpy(b, (const char*)a + le16_to_cpu(a->value_offset), le32_to_cpu(a->value_length)); errno = 0; return (s64)le32_to_cpu(a->value_length); } /* Attribute is not resident. */ /* If no data, return 0. */ if (!(a->data_size)) { errno = 0; return 0; } /* * FIXME: What about attribute lists?!? (AIA) */ /* Decompress the mapping pairs array into a runlist. */ rl = ntfs_mapping_pairs_decompress(vol, a, NULL); if (!rl) { errno = EINVAL; return 0; } /* * FIXED: We were overflowing here in a nasty fashion when we * reach the last cluster in the runlist as the buffer will * only be big enough to hold data_size bytes while we are * reading in allocated_size bytes which is usually larger * than data_size, since the actual data is unlikely to have a * size equal to a multiple of the cluster size! * FIXED2: We were also overflowing here in the same fashion * when the data_size was more than one run smaller than the * allocated size which happens with Windows XP sometimes. */ /* Now load all clusters in the runlist into b. */ for (i = 0, total = 0; rl[i].length; i++) { if (total + (rl[i].length << vol->cluster_size_bits) >= sle64_to_cpu(a->data_size)) { unsigned char *intbuf = NULL; /* * We have reached the last run so we were going to * overflow when executing the ntfs_pread() which is * BAAAAAAAD! * Temporary fix: * Allocate a new buffer with size: * rl[i].length << vol->cluster_size_bits, do the * read into our buffer, then memcpy the correct * amount of data into the caller supplied buffer, * free our buffer, and continue. * We have reached the end of data size so we were * going to overflow in the same fashion. * Temporary fix: same as above. */ intbuf = ntfs_malloc(rl[i].length << vol->cluster_size_bits); if (!intbuf) { free(rl); return 0; } /* * FIXME: If compressed file: Only read if lcn != -1. * Otherwise, we are dealing with a sparse run and we * just memset the user buffer to 0 for the length of * the run, which should be 16 (= compression unit * size). * FIXME: Really only when file is compressed, or can * we have sparse runs in uncompressed files as well? * - Yes we can, in sparse files! But not necessarily * size of 16, just run length. */ r = ntfs_pread(vol->dev, rl[i].lcn << vol->cluster_size_bits, rl[i].length << vol->cluster_size_bits, intbuf); if (r != rl[i].length << vol->cluster_size_bits) { #define ESTR "Error reading attribute value" if (r == -1) ntfs_log_perror(ESTR); else if (r < rl[i].length << vol->cluster_size_bits) { ntfs_log_debug(ESTR ": Ran out of input data.\n"); errno = EIO; } else { ntfs_log_debug(ESTR ": unknown error\n"); errno = EIO; } #undef ESTR free(rl); free(intbuf); return 0; } memcpy(b + total, intbuf, sle64_to_cpu(a->data_size) - total); free(intbuf); total = sle64_to_cpu(a->data_size); break; } /* * FIXME: If compressed file: Only read if lcn != -1. * Otherwise, we are dealing with a sparse run and we just * memset the user buffer to 0 for the length of the run, which * should be 16 (= compression unit size). * FIXME: Really only when file is compressed, or can * we have sparse runs in uncompressed files as well? * - Yes we can, in sparse files! But not necessarily size of * 16, just run length. */ r = ntfs_pread(vol->dev, rl[i].lcn << vol->cluster_size_bits, rl[i].length << vol->cluster_size_bits, b + total); if (r != rl[i].length << vol->cluster_size_bits) { #define ESTR "Error reading attribute value" if (r == -1) ntfs_log_perror(ESTR); else if (r < rl[i].length << vol->cluster_size_bits) { ntfs_log_debug(ESTR ": Ran out of input data.\n"); errno = EIO; } else { ntfs_log_debug(ESTR ": unknown error\n"); errno = EIO; } #undef ESTR free(rl); return 0; } total += r; } free(rl); return total; } /* Already cleaned up code below, but still look for FIXME:... */ /** * __ntfs_attr_init - primary initialization of an ntfs attribute structure * @na: ntfs attribute to initialize * @ni: ntfs inode with which to initialize the ntfs attribute * @type: attribute type * @name: attribute name in little endian Unicode or NULL * @name_len: length of attribute @name in Unicode characters (if @name given) * * Initialize the ntfs attribute @na with @ni, @type, @name, and @name_len. */ static void __ntfs_attr_init(ntfs_attr *na, ntfs_inode *ni, const ATTR_TYPES type, ntfschar *name, const u32 name_len) { na->rl = NULL; na->ni = ni; na->type = type; na->name = name; if (name) na->name_len = name_len; else na->name_len = 0; } /** * ntfs_attr_init - initialize an ntfs_attr with data sizes and status * @na: * @non_resident: * @compressed: * @encrypted: * @sparse: * @allocated_size: * @data_size: * @initialized_size: * @compressed_size: * @compression_unit: * * Final initialization for an ntfs attribute. */ void ntfs_attr_init(ntfs_attr *na, const BOOL non_resident, const ATTR_FLAGS data_flags, const BOOL encrypted, const BOOL sparse, const s64 allocated_size, const s64 data_size, const s64 initialized_size, const s64 compressed_size, const u8 compression_unit) { if (!NAttrInitialized(na)) { na->data_flags = data_flags; if (non_resident) NAttrSetNonResident(na); if (data_flags & ATTR_COMPRESSION_MASK) NAttrSetCompressed(na); if (encrypted) NAttrSetEncrypted(na); if (sparse) NAttrSetSparse(na); na->allocated_size = allocated_size; na->data_size = data_size; na->initialized_size = initialized_size; if ((data_flags & ATTR_COMPRESSION_MASK) || sparse) { ntfs_volume *vol = na->ni->vol; na->compressed_size = compressed_size; na->compression_block_clusters = 1 << compression_unit; na->compression_block_size = 1 << (compression_unit + vol->cluster_size_bits); na->compression_block_size_bits = ffs( na->compression_block_size) - 1; } NAttrSetInitialized(na); } } /** * ntfs_attr_open - open an ntfs attribute for access * @ni: open ntfs inode in which the ntfs attribute resides * @type: attribute type * @name: attribute name in little endian Unicode or AT_UNNAMED or NULL * @name_len: length of attribute @name in Unicode characters (if @name given) * * Allocate a new ntfs attribute structure, initialize it with @ni, @type, * @name, and @name_len, then return it. Return NULL on error with * errno set to the error code. * * If @name is AT_UNNAMED look specifically for an unnamed attribute. If you * do not care whether the attribute is named or not set @name to NULL. In * both those cases @name_len is not used at all. */ ntfs_attr *ntfs_attr_open(ntfs_inode *ni, const ATTR_TYPES type, ntfschar *name, u32 name_len) { ntfs_attr_search_ctx *ctx; ntfs_attr *na = NULL; ntfschar *newname = NULL; ATTR_RECORD *a; BOOL cs; ntfs_log_enter("Entering for inode %lld, attr 0x%x.\n", (unsigned long long)ni->mft_no, type); if (!ni || !ni->vol || !ni->mrec) { errno = EINVAL; goto out; } na = ntfs_calloc(sizeof(ntfs_attr)); if (!na) goto out; if (name && name != AT_UNNAMED && name != NTFS_INDEX_I30) { name = ntfs_ucsndup(name, name_len); if (!name) goto err_out; newname = name; } ctx = ntfs_attr_get_search_ctx(ni, NULL); if (!ctx) goto err_out; if (ntfs_attr_lookup(type, name, name_len, 0, 0, NULL, 0, ctx)) goto put_err_out; a = ctx->attr; if (!name) { if (a->name_length) { name = ntfs_ucsndup((ntfschar*)((u8*)a + le16_to_cpu( a->name_offset)), a->name_length); if (!name) goto put_err_out; newname = name; name_len = a->name_length; } else { name = AT_UNNAMED; name_len = 0; } } __ntfs_attr_init(na, ni, type, name, name_len); /* * Wipe the flags in case they are not zero for an attribute list * attribute. Windows does not complain about invalid flags and chkdsk * does not detect or fix them so we need to cope with it, too. */ if (type == AT_ATTRIBUTE_LIST) a->flags = 0; if ((type == AT_DATA) && !a->initialized_size) { /* * Define/redefine the compression state if stream is * empty, based on the compression mark on parent * directory (for unnamed data streams) or on current * inode (for named data streams). The compression mark * may change any time, the compression state can only * change when stream is wiped out. * * Also prevent compression on NTFS version < 3.0 * or cluster size > 4K or compression is disabled */ a->flags &= ~ATTR_COMPRESSION_MASK; if ((ni->flags & FILE_ATTR_COMPRESSED) && (ni->vol->major_ver >= 3) && NVolCompression(ni->vol) && (ni->vol->cluster_size <= MAX_COMPRESSION_CLUSTER_SIZE)) a->flags |= ATTR_IS_COMPRESSED; } cs = a->flags & (ATTR_IS_COMPRESSED | ATTR_IS_SPARSE); if (na->type == AT_DATA && na->name == AT_UNNAMED && ((!(a->flags & ATTR_IS_SPARSE) != !NAttrSparse(na)) || (!(a->flags & ATTR_IS_ENCRYPTED) != !NAttrEncrypted(na)))) { errno = EIO; ntfs_log_perror("Inode %lld has corrupt attribute flags " "(0x%x <> 0x%x)",(unsigned long long)ni->mft_no, a->flags, na->ni->flags); goto put_err_out; } if (a->non_resident) { if ((a->flags & ATTR_COMPRESSION_MASK) && !a->compression_unit) { errno = EIO; ntfs_log_perror("Compressed inode %lld attr 0x%x has " "no compression unit", (unsigned long long)ni->mft_no, type); goto put_err_out; } ntfs_attr_init(na, TRUE, a->flags, a->flags & ATTR_IS_ENCRYPTED, a->flags & ATTR_IS_SPARSE, sle64_to_cpu(a->allocated_size), sle64_to_cpu(a->data_size), sle64_to_cpu(a->initialized_size), cs ? sle64_to_cpu(a->compressed_size) : 0, cs ? a->compression_unit : 0); } else { s64 l = le32_to_cpu(a->value_length); ntfs_attr_init(na, FALSE, a->flags, a->flags & ATTR_IS_ENCRYPTED, a->flags & ATTR_IS_SPARSE, (l + 7) & ~7, l, l, cs ? (l + 7) & ~7 : 0, 0); } ntfs_attr_put_search_ctx(ctx); out: ntfs_log_leave("\n"); return na; put_err_out: ntfs_attr_put_search_ctx(ctx); err_out: free(newname); free(na); na = NULL; goto out; } /** * ntfs_attr_close - free an ntfs attribute structure * @na: ntfs attribute structure to free * * Release all memory associated with the ntfs attribute @na and then release * @na itself. */ void ntfs_attr_close(ntfs_attr *na) { if (!na) return; if (NAttrNonResident(na) && na->rl) free(na->rl); /* Don't release if using an internal constant. */ if (na->name != AT_UNNAMED && na->name != NTFS_INDEX_I30 && na->name != STREAM_SDS) free(na->name); free(na); } /** * ntfs_attr_map_runlist - map (a part of) a runlist of an ntfs attribute * @na: ntfs attribute for which to map (part of) a runlist * @vcn: map runlist part containing this vcn * * Map the part of a runlist containing the @vcn of the ntfs attribute @na. * * Return 0 on success and -1 on error with errno set to the error code. */ int ntfs_attr_map_runlist(ntfs_attr *na, VCN vcn) { LCN lcn; ntfs_attr_search_ctx *ctx; ntfs_log_trace("Entering for inode 0x%llx, attr 0x%x, vcn 0x%llx.\n", (unsigned long long)na->ni->mft_no, na->type, (long long)vcn); lcn = ntfs_rl_vcn_to_lcn(na->rl, vcn); if (lcn >= 0 || lcn == LCN_HOLE || lcn == LCN_ENOENT) return 0; ctx = ntfs_attr_get_search_ctx(na->ni, NULL); if (!ctx) return -1; /* Find the attribute in the mft record. */ if (!ntfs_attr_lookup(na->type, na->name, na->name_len, CASE_SENSITIVE, vcn, NULL, 0, ctx)) { runlist_element *rl; /* Decode the runlist. */ rl = ntfs_mapping_pairs_decompress(na->ni->vol, ctx->attr, na->rl); if (rl) { na->rl = rl; ntfs_attr_put_search_ctx(ctx); return 0; } } ntfs_attr_put_search_ctx(ctx); return -1; } /** * ntfs_attr_map_whole_runlist - map the whole runlist of an ntfs attribute * @na: ntfs attribute for which to map the runlist * * Map the whole runlist of the ntfs attribute @na. For an attribute made up * of only one attribute extent this is the same as calling * ntfs_attr_map_runlist(na, 0) but for an attribute with multiple extents this * will map the runlist fragments from each of the extents thus giving access * to the entirety of the disk allocation of an attribute. * * Return 0 on success and -1 on error with errno set to the error code. */ int ntfs_attr_map_whole_runlist(ntfs_attr *na) { VCN next_vcn, last_vcn, highest_vcn; ntfs_attr_search_ctx *ctx; ntfs_volume *vol = na->ni->vol; ATTR_RECORD *a; int ret = -1; ntfs_log_enter("Entering for inode %llu, attr 0x%x.\n", (unsigned long long)na->ni->mft_no, na->type); /* avoid multiple full runlist mappings */ if (NAttrFullyMapped(na)) { ret = 0; goto out; } ctx = ntfs_attr_get_search_ctx(na->ni, NULL); if (!ctx) goto out; /* Map all attribute extents one by one. */ next_vcn = last_vcn = highest_vcn = 0; a = NULL; while (1) { runlist_element *rl; int not_mapped = 0; if (ntfs_rl_vcn_to_lcn(na->rl, next_vcn) == LCN_RL_NOT_MAPPED) not_mapped = 1; if (ntfs_attr_lookup(na->type, na->name, na->name_len, CASE_SENSITIVE, next_vcn, NULL, 0, ctx)) break; a = ctx->attr; if (not_mapped) { /* Decode the runlist. */ rl = ntfs_mapping_pairs_decompress(na->ni->vol, a, na->rl); if (!rl) goto err_out; na->rl = rl; } /* Are we in the first extent? */ if (!next_vcn) { if (a->lowest_vcn) { errno = EIO; ntfs_log_perror("First extent of inode %llu " "attribute has non-zero lowest_vcn", (unsigned long long)na->ni->mft_no); goto err_out; } /* Get the last vcn in the attribute. */ last_vcn = sle64_to_cpu(a->allocated_size) >> vol->cluster_size_bits; } /* Get the lowest vcn for the next extent. */ highest_vcn = sle64_to_cpu(a->highest_vcn); next_vcn = highest_vcn + 1; /* Only one extent or error, which we catch below. */ if (next_vcn <= 0) { errno = ENOENT; break; } /* Avoid endless loops due to corruption. */ if (next_vcn < sle64_to_cpu(a->lowest_vcn)) { errno = EIO; ntfs_log_perror("Inode %llu has corrupt attribute list", (unsigned long long)na->ni->mft_no); goto err_out; } } if (!a) { ntfs_log_perror("Couldn't find attribute for runlist mapping"); goto err_out; } if (highest_vcn && highest_vcn != last_vcn - 1) { errno = EIO; ntfs_log_perror("Failed to load full runlist: inode: %llu " "highest_vcn: 0x%llx last_vcn: 0x%llx", (unsigned long long)na->ni->mft_no, (long long)highest_vcn, (long long)last_vcn); goto err_out; } if (errno == ENOENT) { NAttrSetFullyMapped(na); ret = 0; } err_out: ntfs_attr_put_search_ctx(ctx); out: ntfs_log_leave("\n"); return ret; } /** * ntfs_attr_vcn_to_lcn - convert a vcn into a lcn given an ntfs attribute * @na: ntfs attribute whose runlist to use for conversion * @vcn: vcn to convert * * Convert the virtual cluster number @vcn of an attribute into a logical * cluster number (lcn) of a device using the runlist @na->rl to map vcns to * their corresponding lcns. * * If the @vcn is not mapped yet, attempt to map the attribute extent * containing the @vcn and retry the vcn to lcn conversion. * * Since lcns must be >= 0, we use negative return values with special meaning: * * Return value Meaning / Description * ========================================== * -1 = LCN_HOLE Hole / not allocated on disk. * -3 = LCN_ENOENT There is no such vcn in the attribute. * -4 = LCN_EINVAL Input parameter error. * -5 = LCN_EIO Corrupt fs, disk i/o error, or not enough memory. */ LCN ntfs_attr_vcn_to_lcn(ntfs_attr *na, const VCN vcn) { LCN lcn; BOOL is_retry = FALSE; if (!na || !NAttrNonResident(na) || vcn < 0) return (LCN)LCN_EINVAL; ntfs_log_trace("Entering for inode 0x%llx, attr 0x%x.\n", (unsigned long long)na->ni->mft_no, na->type); retry: /* Convert vcn to lcn. If that fails map the runlist and retry once. */ lcn = ntfs_rl_vcn_to_lcn(na->rl, vcn); if (lcn >= 0) return lcn; if (!is_retry && !ntfs_attr_map_runlist(na, vcn)) { is_retry = TRUE; goto retry; } /* * If the attempt to map the runlist failed, or we are getting * LCN_RL_NOT_MAPPED despite having mapped the attribute extent * successfully, something is really badly wrong... */ if (!is_retry || lcn == (LCN)LCN_RL_NOT_MAPPED) return (LCN)LCN_EIO; /* lcn contains the appropriate error code. */ return lcn; } /** * ntfs_attr_find_vcn - find a vcn in the runlist of an ntfs attribute * @na: ntfs attribute whose runlist to search * @vcn: vcn to find * * Find the virtual cluster number @vcn in the runlist of the ntfs attribute * @na and return the the address of the runlist element containing the @vcn. * * Note you need to distinguish between the lcn of the returned runlist * element being >= 0 and LCN_HOLE. In the later case you have to return zeroes * on read and allocate clusters on write. You need to update the runlist, the * attribute itself as well as write the modified mft record to disk. * * If there is an error return NULL with errno set to the error code. The * following error codes are defined: * EINVAL Input parameter error. * ENOENT There is no such vcn in the runlist. * ENOMEM Not enough memory. * EIO I/O error or corrupt metadata. */ runlist_element *ntfs_attr_find_vcn(ntfs_attr *na, const VCN vcn) { runlist_element *rl; BOOL is_retry = FALSE; if (!na || !NAttrNonResident(na) || vcn < 0) { errno = EINVAL; return NULL; } ntfs_log_trace("Entering for inode 0x%llx, attr 0x%x, vcn %llx\n", (unsigned long long)na->ni->mft_no, na->type, (long long)vcn); retry: rl = na->rl; if (!rl) goto map_rl; if (vcn < rl[0].vcn) goto map_rl; while (rl->length) { if (vcn < rl[1].vcn) { if (rl->lcn >= (LCN)LCN_HOLE) return rl; break; } rl++; } switch (rl->lcn) { case (LCN)LCN_RL_NOT_MAPPED: goto map_rl; case (LCN)LCN_ENOENT: errno = ENOENT; break; case (LCN)LCN_EINVAL: errno = EINVAL; break; default: errno = EIO; break; } return NULL; map_rl: /* The @vcn is in an unmapped region, map the runlist and retry. */ if (!is_retry && !ntfs_attr_map_runlist(na, vcn)) { is_retry = TRUE; goto retry; } /* * If we already retried or the mapping attempt failed something has * gone badly wrong. EINVAL and ENOENT coming from a failed mapping * attempt are equivalent to errors for us as they should not happen * in our code paths. */ if (is_retry || errno == EINVAL || errno == ENOENT) errno = EIO; return NULL; } /** * ntfs_attr_pread_i - see description at ntfs_attr_pread() */ static s64 ntfs_attr_pread_i(ntfs_attr *na, const s64 pos, s64 count, void *b) { s64 br, to_read, ofs, total, total2, max_read, max_init; ntfs_volume *vol; runlist_element *rl; u16 efs_padding_length; /* Sanity checking arguments is done in ntfs_attr_pread(). */ if ((na->data_flags & ATTR_COMPRESSION_MASK) && NAttrNonResident(na)) { if ((na->data_flags & ATTR_COMPRESSION_MASK) == ATTR_IS_COMPRESSED) return ntfs_compressed_attr_pread(na, pos, count, b); else { /* compression mode not supported */ errno = EOPNOTSUPP; return -1; } } /* * Encrypted non-resident attributes are not supported. We return * access denied, which is what Windows NT4 does, too. * However, allow if mounted with efs_raw option */ vol = na->ni->vol; if (!vol->efs_raw && NAttrEncrypted(na) && NAttrNonResident(na)) { errno = EACCES; return -1; } if (!count) return 0; /* * Truncate reads beyond end of attribute, * but round to next 512 byte boundary for encrypted * attributes with efs_raw mount option */ max_read = na->data_size; max_init = na->initialized_size; if (na->ni->vol->efs_raw && (na->data_flags & ATTR_IS_ENCRYPTED) && NAttrNonResident(na)) { if (na->data_size != na->initialized_size) { ntfs_log_error("uninitialized encrypted file not supported\n"); errno = EINVAL; return -1; } max_init = max_read = ((na->data_size + 511) & ~511) + 2; } if (pos + count > max_read) { if (pos >= max_read) return 0; count = max_read - pos; } /* If it is a resident attribute, get the value from the mft record. */ if (!NAttrNonResident(na)) { ntfs_attr_search_ctx *ctx; char *val; ctx = ntfs_attr_get_search_ctx(na->ni, NULL); if (!ctx) return -1; if (ntfs_attr_lookup(na->type, na->name, na->name_len, 0, 0, NULL, 0, ctx)) { res_err_out: ntfs_attr_put_search_ctx(ctx); return -1; } val = (char*)ctx->attr + le16_to_cpu(ctx->attr->value_offset); if (val < (char*)ctx->attr || val + le32_to_cpu(ctx->attr->value_length) > (char*)ctx->mrec + vol->mft_record_size) { errno = EIO; ntfs_log_perror("%s: Sanity check failed", __FUNCTION__); goto res_err_out; } memcpy(b, val + pos, count); ntfs_attr_put_search_ctx(ctx); return count; } total = total2 = 0; /* Zero out reads beyond initialized size. */ if (pos + count > max_init) { if (pos >= max_init) { memset(b, 0, count); return count; } total2 = pos + count - max_init; count -= total2; memset((u8*)b + count, 0, total2); } /* * for encrypted non-resident attributes with efs_raw set * the last two bytes aren't read from disk but contain * the number of padding bytes so original size can be * restored */ if (na->ni->vol->efs_raw && (na->data_flags & ATTR_IS_ENCRYPTED) && ((pos + count) > max_init-2)) { efs_padding_length = 511 - ((na->data_size - 1) & 511); if (pos+count == max_init) { if (count == 1) { *((u8*)b+count-1) = (u8)(efs_padding_length >> 8); count--; total2++; } else { *(u16*)((u8*)b+count-2) = cpu_to_le16(efs_padding_length); count -= 2; total2 +=2; } } else { *((u8*)b+count-1) = (u8)(efs_padding_length & 0xff); count--; total2++; } } /* Find the runlist element containing the vcn. */ rl = ntfs_attr_find_vcn(na, pos >> vol->cluster_size_bits); if (!rl) { /* * If the vcn is not present it is an out of bounds read. * However, we already truncated the read to the data_size, * so getting this here is an error. */ if (errno == ENOENT) { errno = EIO; ntfs_log_perror("%s: Failed to find VCN #1", __FUNCTION__); } return -1; } /* * Gather the requested data into the linear destination buffer. Note, * a partial final vcn is taken care of by the @count capping of read * length. */ ofs = pos - (rl->vcn << vol->cluster_size_bits); for (; count; rl++, ofs = 0) { if (rl->lcn == LCN_RL_NOT_MAPPED) { rl = ntfs_attr_find_vcn(na, rl->vcn); if (!rl) { if (errno == ENOENT) { errno = EIO; ntfs_log_perror("%s: Failed to find VCN #2", __FUNCTION__); } goto rl_err_out; } /* Needed for case when runs merged. */ ofs = pos + total - (rl->vcn << vol->cluster_size_bits); } if (!rl->length) { errno = EIO; ntfs_log_perror("%s: Zero run length", __FUNCTION__); goto rl_err_out; } if (rl->lcn < (LCN)0) { if (rl->lcn != (LCN)LCN_HOLE) { ntfs_log_perror("%s: Bad run (%lld)", __FUNCTION__, (long long)rl->lcn); goto rl_err_out; } /* It is a hole, just zero the matching @b range. */ to_read = min(count, (rl->length << vol->cluster_size_bits) - ofs); memset(b, 0, to_read); /* Update progress counters. */ total += to_read; count -= to_read; b = (u8*)b + to_read; continue; } /* It is a real lcn, read it into @dst. */ to_read = min(count, (rl->length << vol->cluster_size_bits) - ofs); retry: ntfs_log_trace("Reading %lld bytes from vcn %lld, lcn %lld, ofs" " %lld.\n", (long long)to_read, (long long)rl->vcn, (long long )rl->lcn, (long long)ofs); br = ntfs_pread(vol->dev, (rl->lcn << vol->cluster_size_bits) + ofs, to_read, b); /* If everything ok, update progress counters and continue. */ if (br > 0) { total += br; count -= br; b = (u8*)b + br; } if (br == to_read) continue; /* If the syscall was interrupted, try again. */ if (br == (s64)-1 && errno == EINTR) goto retry; if (total) return total; if (!br) errno = EIO; ntfs_log_perror("%s: ntfs_pread failed", __FUNCTION__); return -1; } /* Finally, return the number of bytes read. */ return total + total2; rl_err_out: if (total) return total; errno = EIO; return -1; } /** * ntfs_attr_pread - read from an attribute specified by an ntfs_attr structure * @na: ntfs attribute to read from * @pos: byte position in the attribute to begin reading from * @count: number of bytes to read * @b: output data buffer * * This function will read @count bytes starting at offset @pos from the ntfs * attribute @na into the data buffer @b. * * On success, return the number of successfully read bytes. If this number is * lower than @count this means that the read reached end of file or that an * error was encountered during the read so that the read is partial. 0 means * end of file or nothing was read (also return 0 when @count is 0). * * On error and nothing has been read, return -1 with errno set appropriately * to the return code of ntfs_pread(), or to EINVAL in case of invalid * arguments. */ s64 ntfs_attr_pread(ntfs_attr *na, const s64 pos, s64 count, void *b) { s64 ret; if (!na || !na->ni || !na->ni->vol || !b || pos < 0 || count < 0) { errno = EINVAL; ntfs_log_perror("%s: na=%p b=%p pos=%lld count=%lld", __FUNCTION__, na, b, (long long)pos, (long long)count); return -1; } ntfs_log_enter("Entering for inode %lld attr 0x%x pos %lld count " "%lld\n", (unsigned long long)na->ni->mft_no, na->type, (long long)pos, (long long)count); ret = ntfs_attr_pread_i(na, pos, count, b); ntfs_log_leave("\n"); return ret; } static int ntfs_attr_fill_zero(ntfs_attr *na, s64 pos, s64 count) { char *buf; s64 written, size, end = pos + count; s64 ofsi; const runlist_element *rli; ntfs_volume *vol; int ret = -1; ntfs_log_trace("pos %lld, count %lld\n", (long long)pos, (long long)count); if (!na || pos < 0 || count < 0) { errno = EINVAL; goto err_out; } buf = ntfs_calloc(NTFS_BUF_SIZE); if (!buf) goto err_out; rli = na->rl; ofsi = 0; vol = na->ni->vol; while (pos < end) { while (rli->length && (ofsi + (rli->length << vol->cluster_size_bits) <= pos)) { ofsi += (rli->length << vol->cluster_size_bits); rli++; } size = min(end - pos, NTFS_BUF_SIZE); written = ntfs_rl_pwrite(vol, rli, ofsi, pos, size, buf); if (written <= 0) { ntfs_log_perror("Failed to zero space"); goto err_free; } pos += written; } ret = 0; err_free: free(buf); err_out: return ret; } static int ntfs_attr_fill_hole(ntfs_attr *na, s64 count, s64 *ofs, runlist_element **rl, VCN *update_from) { s64 to_write; s64 need; ntfs_volume *vol = na->ni->vol; int eo, ret = -1; runlist *rlc; LCN lcn_seek_from = -1; VCN cur_vcn, from_vcn; to_write = min(count, ((*rl)->length << vol->cluster_size_bits) - *ofs); cur_vcn = (*rl)->vcn; from_vcn = (*rl)->vcn + (*ofs >> vol->cluster_size_bits); ntfs_log_trace("count: %lld, cur_vcn: %lld, from: %lld, to: %lld, ofs: " "%lld\n", (long long)count, (long long)cur_vcn, (long long)from_vcn, (long long)to_write, (long long)*ofs); /* Map whole runlist to be able update mapping pairs later. */ if (ntfs_attr_map_whole_runlist(na)) goto err_out; /* Restore @*rl, it probably get lost during runlist mapping. */ *rl = ntfs_attr_find_vcn(na, cur_vcn); if (!*rl) { ntfs_log_error("Failed to find run after mapping runlist. " "Please report to %s.\n", NTFS_DEV_LIST); errno = EIO; goto err_out; } /* Search backwards to find the best lcn to start seek from. */ rlc = *rl; while (rlc->vcn) { rlc--; if (rlc->lcn >= 0) { /* * avoid fragmenting a compressed file * Windows does not do that, and that may * not be desirable for files which can * be updated */ if (na->data_flags & ATTR_COMPRESSION_MASK) lcn_seek_from = rlc->lcn + rlc->length; else lcn_seek_from = rlc->lcn + (from_vcn - rlc->vcn); break; } } if (lcn_seek_from == -1) { /* Backwards search failed, search forwards. */ rlc = *rl; while (rlc->length) { rlc++; if (rlc->lcn >= 0) { lcn_seek_from = rlc->lcn - (rlc->vcn - from_vcn); if (lcn_seek_from < -1) lcn_seek_from = -1; break; } } } need = ((*ofs + to_write - 1) >> vol->cluster_size_bits) + 1 + (*rl)->vcn - from_vcn; if ((na->data_flags & ATTR_COMPRESSION_MASK) && (need < na->compression_block_clusters)) { /* * for a compressed file, be sure to allocate the full * compression block, as we may need space to decompress * existing compressed data. * So allocate the space common to compression block * and existing hole. */ VCN alloc_vcn; if ((from_vcn & -na->compression_block_clusters) <= (*rl)->vcn) alloc_vcn = (*rl)->vcn; else alloc_vcn = from_vcn & -na->compression_block_clusters; need = (alloc_vcn | (na->compression_block_clusters - 1)) + 1 - alloc_vcn; if (need > (*rl)->length) { ntfs_log_error("Cannot allocate %lld clusters" " within a hole of %lld\n", (long long)need, (long long)(*rl)->length); errno = EIO; goto err_out; } rlc = ntfs_cluster_alloc(vol, alloc_vcn, need, lcn_seek_from, DATA_ZONE); } else rlc = ntfs_cluster_alloc(vol, from_vcn, need, lcn_seek_from, DATA_ZONE); if (!rlc) goto err_out; if (na->data_flags & (ATTR_COMPRESSION_MASK | ATTR_IS_SPARSE)) na->compressed_size += need << vol->cluster_size_bits; *rl = ntfs_runlists_merge(na->rl, rlc); /* * For a compressed attribute, we must be sure there are two * available entries, so reserve them before it gets too late. */ if (*rl && (na->data_flags & ATTR_COMPRESSION_MASK)) { runlist_element *oldrl = na->rl; na->rl = *rl; *rl = ntfs_rl_extend(na,*rl,2); if (!*rl) na->rl = oldrl; /* restore to original if failed */ } if (!*rl) { eo = errno; ntfs_log_perror("Failed to merge runlists"); if (ntfs_cluster_free_from_rl(vol, rlc)) { ntfs_log_perror("Failed to free hot clusters. " "Please run chkdsk /f"); } errno = eo; goto err_out; } na->unused_runs = 2; na->rl = *rl; if ((*update_from == -1) || (from_vcn < *update_from)) *update_from = from_vcn; *rl = ntfs_attr_find_vcn(na, cur_vcn); if (!*rl) { /* * It's definitely a BUG, if we failed to find @cur_vcn, because * we missed it during instantiating of the hole. */ ntfs_log_error("Failed to find run after hole instantiation. " "Please report to %s.\n", NTFS_DEV_LIST); errno = EIO; goto err_out; } /* If leaved part of the hole go to the next run. */ if ((*rl)->lcn < 0) (*rl)++; /* Now LCN shoudn't be less than 0. */ if ((*rl)->lcn < 0) { ntfs_log_error("BUG! LCN is lesser than 0. " "Please report to the %s.\n", NTFS_DEV_LIST); errno = EIO; goto err_out; } if (*ofs) { /* Clear non-sparse region from @cur_vcn to @*ofs. */ if (ntfs_attr_fill_zero(na, cur_vcn << vol->cluster_size_bits, *ofs)) goto err_out; } if ((*rl)->vcn < cur_vcn) { /* * Clusters that replaced hole are merged with * previous run, so we need to update offset. */ *ofs += (cur_vcn - (*rl)->vcn) << vol->cluster_size_bits; } if ((*rl)->vcn > cur_vcn) { /* * We left part of the hole, so we need to update offset */ *ofs -= ((*rl)->vcn - cur_vcn) << vol->cluster_size_bits; } ret = 0; err_out: return ret; } static int stuff_hole(ntfs_attr *na, const s64 pos); /* * Split an existing hole for overwriting with data * The hole may have to be split into two or three parts, so * that the overwritten part fits within a single compression block * * No cluster allocation is needed, this will be done later in * standard hole filling, hence no need to reserve runs for * future needs. * * Returns the number of clusters with existing compressed data * in the compression block to be written to * (or the full block, if it was a full hole) * -1 if there were an error */ static int split_compressed_hole(ntfs_attr *na, runlist_element **prl, s64 pos, s64 count, VCN *update_from) { int compressed_part; int cluster_size_bits = na->ni->vol->cluster_size_bits; runlist_element *rl = *prl; compressed_part = na->compression_block_clusters; /* reserve entries in runlist if we have to split */ if (rl->length > na->compression_block_clusters) { *prl = ntfs_rl_extend(na,*prl,2); if (!*prl) { compressed_part = -1; } else { rl = *prl; na->unused_runs = 2; } } if (*prl && (rl->length > na->compression_block_clusters)) { /* * Locate the update part relative to beginning of * current run */ int beginwrite = (pos >> cluster_size_bits) - rl->vcn; s32 endblock = (((pos + count - 1) >> cluster_size_bits) | (na->compression_block_clusters - 1)) + 1 - rl->vcn; compressed_part = na->compression_block_clusters - (rl->length & (na->compression_block_clusters - 1)); if ((beginwrite + compressed_part) >= na->compression_block_clusters) compressed_part = na->compression_block_clusters; /* * if the run ends beyond end of needed block * we have to split the run */ if (endblock < rl[0].length) { runlist_element *xrl; int n; /* * we have to split into three parts if the run * does not end within the first compression block. * This means the hole begins before the * compression block. */ if (endblock > na->compression_block_clusters) { if (na->unused_runs < 2) { ntfs_log_error("No free run, case 1\n"); } na->unused_runs -= 2; xrl = rl; n = 0; while (xrl->length) { xrl++; n++; } do { xrl[2] = *xrl; xrl--; } while (xrl != rl); rl[1].length = na->compression_block_clusters; rl[2].length = rl[0].length - endblock; rl[0].length = endblock - na->compression_block_clusters; rl[1].lcn = LCN_HOLE; rl[2].lcn = LCN_HOLE; rl[1].vcn = rl[0].vcn + rl[0].length; rl[2].vcn = rl[1].vcn + na->compression_block_clusters; rl = ++(*prl); } else { /* * split into two parts and use the * first one */ if (!na->unused_runs) { ntfs_log_error("No free run, case 2\n"); } na->unused_runs--; xrl = rl; n = 0; while (xrl->length) { xrl++; n++; } do { xrl[1] = *xrl; xrl--; } while (xrl != rl); if (beginwrite < endblock) { /* we will write into the first part of hole */ rl[1].length = rl[0].length - endblock; rl[0].length = endblock; rl[1].vcn = rl[0].vcn + rl[0].length; rl[1].lcn = LCN_HOLE; } else { /* we will write into the second part of hole */ // impossible ? rl[1].length = rl[0].length - endblock; rl[0].length = endblock; rl[1].vcn = rl[0].vcn + rl[0].length; rl[1].lcn = LCN_HOLE; rl = ++(*prl); } } } else { if (rl[1].length) { runlist_element *xrl; int n; /* * split into two parts and use the * last one */ if (!na->unused_runs) { ntfs_log_error("No free run, case 4\n"); } na->unused_runs--; xrl = rl; n = 0; while (xrl->length) { xrl++; n++; } do { xrl[1] = *xrl; xrl--; } while (xrl != rl); } else { rl[2].lcn = rl[1].lcn; rl[2].vcn = rl[1].vcn; rl[2].length = rl[1].length; } rl[1].vcn -= na->compression_block_clusters; rl[1].lcn = LCN_HOLE; rl[1].length = na->compression_block_clusters; rl[0].length -= na->compression_block_clusters; if (pos >= (rl[1].vcn << cluster_size_bits)) { rl = ++(*prl); } } if ((*update_from == -1) || ((*prl)->vcn < *update_from)) *update_from = (*prl)->vcn; } return (compressed_part); } /* * Borrow space from adjacent hole for appending data * The hole may have to be split so that the end of hole is not * affected by cluster allocation and overwriting * Cluster allocation is needed for the overwritten compression block * * Must always leave two unused entries in the runlist * * Returns the number of clusters with existing compressed data * in the compression block to be written to * -1 if there were an error */ static int borrow_from_hole(ntfs_attr *na, runlist_element **prl, s64 pos, s64 count, VCN *update_from, BOOL wasnonresident) { int compressed_part = 0; int cluster_size_bits = na->ni->vol->cluster_size_bits; runlist_element *rl = *prl; s32 endblock; long long allocated; runlist_element *zrl; int irl; BOOL undecided; BOOL nothole; /* check whether the compression block is fully allocated */ endblock = (((pos + count - 1) >> cluster_size_bits) | (na->compression_block_clusters - 1)) + 1 - rl->vcn; allocated = 0; zrl = rl; irl = 0; while (zrl->length && (zrl->lcn >= 0) && (allocated < endblock)) { allocated += zrl->length; zrl++; irl++; } undecided = (allocated < endblock) && (zrl->lcn == LCN_RL_NOT_MAPPED); nothole = (allocated >= endblock) || (zrl->lcn != LCN_HOLE); if (undecided || nothole) { runlist_element *orl = na->rl; s64 olcn = (*prl)->lcn; /* * Map the full runlist (needed to compute the * compressed size), unless the runlist has not * yet been created (data just made non-resident) */ irl = *prl - na->rl; if (!NAttrBeingNonResident(na) && ntfs_attr_map_whole_runlist(na)) { rl = (runlist_element*)NULL; } else { /* * Mapping the runlist may cause its relocation, * and relocation may be at the same place with * relocated contents. * Have to find the current run again when this * happens. */ if ((na->rl != orl) || ((*prl)->lcn != olcn)) { zrl = &na->rl[irl]; while (zrl->length && (zrl->lcn != olcn)) zrl++; *prl = zrl; } if (!(*prl)->length) { ntfs_log_error("Mapped run not found," " inode %lld lcn 0x%llx\n", (long long)na->ni->mft_no, (long long)olcn); rl = (runlist_element*)NULL; } else { rl = ntfs_rl_extend(na,*prl,2); na->unused_runs = 2; } } *prl = rl; if (rl && undecided) { allocated = 0; zrl = rl; irl = 0; while (zrl->length && (zrl->lcn >= 0) && (allocated < endblock)) { allocated += zrl->length; zrl++; irl++; } } } /* * compression block not fully allocated and followed * by a hole : we must allocate in the hole. */ if (rl && (allocated < endblock) && (zrl->lcn == LCN_HOLE)) { s64 xofs; /* * split the hole if not fully needed */ if ((allocated + zrl->length) > endblock) { runlist_element *xrl; *prl = ntfs_rl_extend(na,*prl,1); if (*prl) { /* beware : rl was reallocated */ rl = *prl; zrl = &rl[irl]; na->unused_runs = 0; xrl = zrl; while (xrl->length) xrl++; do { xrl[1] = *xrl; } while (xrl-- != zrl); zrl->length = endblock - allocated; zrl[1].length -= zrl->length; zrl[1].vcn = zrl->vcn + zrl->length; } } if (*prl) { if (wasnonresident) compressed_part = na->compression_block_clusters - zrl->length; xofs = 0; if (ntfs_attr_fill_hole(na, zrl->length << cluster_size_bits, &xofs, &zrl, update_from)) compressed_part = -1; else { /* go back to initial cluster, now reallocated */ while (zrl->vcn > (pos >> cluster_size_bits)) zrl--; *prl = zrl; } } } if (!*prl) { ntfs_log_error("No elements to borrow from a hole\n"); compressed_part = -1; } else if ((*update_from == -1) || ((*prl)->vcn < *update_from)) *update_from = (*prl)->vcn; return (compressed_part); } /** * ntfs_attr_pwrite - positioned write to an ntfs attribute * @na: ntfs attribute to write to * @pos: position in the attribute to write to * @count: number of bytes to write * @b: data buffer to write to disk * * This function will write @count bytes from data buffer @b to ntfs attribute * @na at position @pos. * * On success, return the number of successfully written bytes. If this number * is lower than @count this means that an error was encountered during the * write so that the write is partial. 0 means nothing was written (also return * 0 when @count is 0). * * On error and nothing has been written, return -1 with errno set * appropriately to the return code of ntfs_pwrite(), or to EINVAL in case of * invalid arguments. */ s64 ntfs_attr_pwrite(ntfs_attr *na, const s64 pos, s64 count, const void *b) { s64 written, to_write, ofs, old_initialized_size, old_data_size; s64 total = 0; VCN update_from = -1; ntfs_volume *vol; s64 fullcount; ntfs_attr_search_ctx *ctx = NULL; runlist_element *rl; s64 hole_end; int eo; int compressed_part; struct { unsigned int undo_initialized_size : 1; unsigned int undo_data_size : 1; } need_to = { 0, 0 }; BOOL wasnonresident = FALSE; BOOL compressed; BOOL updatemap; ntfs_log_enter("Entering for inode %lld, attr 0x%x, pos 0x%llx, count " "0x%llx.\n", (long long)na->ni->mft_no, na->type, (long long)pos, (long long)count); if (!na || !na->ni || !na->ni->vol || !b || pos < 0 || count < 0) { errno = EINVAL; ntfs_log_perror("%s", __FUNCTION__); goto errno_set; } vol = na->ni->vol; compressed = (na->data_flags & ATTR_COMPRESSION_MASK) != const_cpu_to_le16(0); na->unused_runs = 0; /* prepare overflow checks */ /* * Encrypted attributes are only supported in raw mode. We return * access denied, which is what Windows NT4 does, too. * Moreover a file cannot be both encrypted and compressed. */ if ((na->data_flags & ATTR_IS_ENCRYPTED) && (compressed || !vol->efs_raw)) { errno = EACCES; goto errno_set; } /* * Fill the gap, when writing beyond the end of a compressed * file. This will make recursive calls */ if (compressed && (na->type == AT_DATA) && (pos > na->initialized_size) && stuff_hole(na,pos)) goto errno_set; /* If this is a compressed attribute it needs special treatment. */ wasnonresident = NAttrNonResident(na) != 0; /* * Compression is restricted to data streams and * only ATTR_IS_COMPRESSED compression mode is supported. */ if (compressed && ((na->type != AT_DATA) || ((na->data_flags & ATTR_COMPRESSION_MASK) != ATTR_IS_COMPRESSED))) { errno = EOPNOTSUPP; goto errno_set; } if (!count) goto out; /* for a compressed file, get prepared to reserve a full block */ fullcount = count; /* If the write reaches beyond the end, extend the attribute. */ old_data_size = na->data_size; if (pos + count > na->data_size) { if (ntfs_attr_truncate(na, pos + count)) { ntfs_log_perror("Failed to enlarge attribute"); goto errno_set; } /* resizing may change the compression mode */ compressed = (na->data_flags & ATTR_COMPRESSION_MASK) != const_cpu_to_le16(0); need_to.undo_data_size = 1; } /* * For compressed data, a single full block was allocated * to deal with compression, possibly in a previous call. * We are not able to process several blocks because * some clusters are freed after compression and * new allocations have to be done before proceeding, * so truncate the requested count if needed (big buffers). */ if (compressed) { fullcount = (pos | (na->compression_block_size - 1)) + 1 - pos; if (count > fullcount) count = fullcount; } old_initialized_size = na->initialized_size; /* If it is a resident attribute, write the data to the mft record. */ if (!NAttrNonResident(na)) { char *val; ctx = ntfs_attr_get_search_ctx(na->ni, NULL); if (!ctx) goto err_out; if (ntfs_attr_lookup(na->type, na->name, na->name_len, 0, 0, NULL, 0, ctx)) { ntfs_log_perror("%s: lookup failed", __FUNCTION__); goto err_out; } val = (char*)ctx->attr + le16_to_cpu(ctx->attr->value_offset); if (val < (char*)ctx->attr || val + le32_to_cpu(ctx->attr->value_length) > (char*)ctx->mrec + vol->mft_record_size) { errno = EIO; ntfs_log_perror("%s: Sanity check failed", __FUNCTION__); goto err_out; } memcpy(val + pos, b, count); if (ntfs_mft_record_write(vol, ctx->ntfs_ino->mft_no, ctx->mrec)) { /* * NOTE: We are in a bad state at this moment. We have * dirtied the mft record but we failed to commit it to * disk. Since we have read the mft record ok before, * it is unlikely to fail writing it, so is ok to just * return error here... (AIA) */ ntfs_log_perror("%s: failed to write mft record", __FUNCTION__); goto err_out; } ntfs_attr_put_search_ctx(ctx); total = count; goto out; } /* Handle writes beyond initialized_size. */ if (pos + count > na->initialized_size) { if (ntfs_attr_map_whole_runlist(na)) goto err_out; /* * For a compressed attribute, we must be sure there is an * available entry, and, when reopening a compressed file, * we may need to split a hole. So reserve the entries * before it gets too late. */ if (compressed) { na->rl = ntfs_rl_extend(na,na->rl,2); if (!na->rl) goto err_out; na->unused_runs = 2; } /* Set initialized_size to @pos + @count. */ ctx = ntfs_attr_get_search_ctx(na->ni, NULL); if (!ctx) goto err_out; if (ntfs_attr_lookup(na->type, na->name, na->name_len, 0, 0, NULL, 0, ctx)) goto err_out; /* If write starts beyond initialized_size, zero the gap. */ if (pos > na->initialized_size) if (ntfs_attr_fill_zero(na, na->initialized_size, pos - na->initialized_size)) goto err_out; ctx->attr->initialized_size = cpu_to_sle64(pos + count); /* fix data_size for compressed files */ if (compressed) { na->data_size = pos + count; ctx->attr->data_size = ctx->attr->initialized_size; } if (ntfs_mft_record_write(vol, ctx->ntfs_ino->mft_no, ctx->mrec)) { /* * Undo the change in the in-memory copy and send it * back for writing. */ ctx->attr->initialized_size = cpu_to_sle64(old_initialized_size); ntfs_mft_record_write(vol, ctx->ntfs_ino->mft_no, ctx->mrec); goto err_out; } na->initialized_size = pos + count; #if CACHE_NIDATA_SIZE if (na->ni->mrec->flags & MFT_RECORD_IS_DIRECTORY ? na->type == AT_INDEX_ROOT && na->name == NTFS_INDEX_I30 : na->type == AT_DATA && na->name == AT_UNNAMED) { na->ni->data_size = na->data_size; if ((compressed || NAttrSparse(na)) && NAttrNonResident(na)) na->ni->allocated_size = na->compressed_size; else na->ni->allocated_size = na->allocated_size; set_nino_flag(na->ni,KnownSize); } #endif ntfs_attr_put_search_ctx(ctx); ctx = NULL; /* * NOTE: At this point the initialized_size in the mft record * has been updated BUT there is random data on disk thus if * we decide to abort, we MUST change the initialized_size * again. */ need_to.undo_initialized_size = 1; } /* Find the runlist element containing the vcn. */ rl = ntfs_attr_find_vcn(na, pos >> vol->cluster_size_bits); if (!rl) { /* * If the vcn is not present it is an out of bounds write. * However, we already extended the size of the attribute, * so getting this here must be an error of some kind. */ if (errno == ENOENT) { errno = EIO; ntfs_log_perror("%s: Failed to find VCN #3", __FUNCTION__); } goto err_out; } /* * Determine if there is compressed data in the current * compression block (when appending to an existing file). * If so, decompression will be needed, and the full block * must be allocated to be identified as uncompressed. * This comes in two variants, depending on whether * compression has saved at least one cluster. * The compressed size can never be over full size by * more than 485 (maximum for 15 compression blocks * compressed to 4098 and the last 3640 bytes compressed * to 3640 + 3640/8 = 4095, with 15*2 + 4095 - 3640 = 485) * This is less than the smallest cluster, so the hole is * is never beyond the cluster next to the position of * the first uncompressed byte to write. */ compressed_part = 0; if (compressed) { if ((rl->lcn == (LCN)LCN_HOLE) && wasnonresident) { if (rl->length < na->compression_block_clusters) /* * the needed block is in a hole smaller * than the compression block : we can use * it fully */ compressed_part = na->compression_block_clusters - rl->length; else { /* * the needed block is in a hole bigger * than the compression block : we must * split the hole and use it partially */ compressed_part = split_compressed_hole(na, &rl, pos, count, &update_from); } } else { if (rl->lcn >= 0) { /* * the needed block contains data, make * sure the full compression block is * allocated. Borrow from hole if needed */ compressed_part = borrow_from_hole(na, &rl, pos, count, &update_from, wasnonresident); } } if (compressed_part < 0) goto err_out; /* just making non-resident, so not yet compressed */ if (NAttrBeingNonResident(na) && (compressed_part < na->compression_block_clusters)) compressed_part = 0; } ofs = pos - (rl->vcn << vol->cluster_size_bits); /* * Scatter the data from the linear data buffer to the volume. Note, a * partial final vcn is taken care of by the @count capping of write * length. */ for (hole_end = 0; count; rl++, ofs = 0, hole_end = 0) { if (rl->lcn == LCN_RL_NOT_MAPPED) { rl = ntfs_attr_find_vcn(na, rl->vcn); if (!rl) { if (errno == ENOENT) { errno = EIO; ntfs_log_perror("%s: Failed to find VCN" " #4", __FUNCTION__); } goto rl_err_out; } /* Needed for case when runs merged. */ ofs = pos + total - (rl->vcn << vol->cluster_size_bits); } if (!rl->length) { errno = EIO; ntfs_log_perror("%s: Zero run length", __FUNCTION__); goto rl_err_out; } if (rl->lcn < (LCN)0) { hole_end = rl->vcn + rl->length; if (rl->lcn != (LCN)LCN_HOLE) { errno = EIO; ntfs_log_perror("%s: Unexpected LCN (%lld)", __FUNCTION__, (long long)rl->lcn); goto rl_err_out; } if (ntfs_attr_fill_hole(na, fullcount, &ofs, &rl, &update_from)) goto err_out; } if (compressed) { while (rl->length && (ofs >= (rl->length << vol->cluster_size_bits))) { ofs -= rl->length << vol->cluster_size_bits; rl++; } } /* It is a real lcn, write it to the volume. */ to_write = min(count, (rl->length << vol->cluster_size_bits) - ofs); retry: ntfs_log_trace("Writing %lld bytes to vcn %lld, lcn %lld, ofs " "%lld.\n", (long long)to_write, (long long)rl->vcn, (long long)rl->lcn, (long long)ofs); if (!NVolReadOnly(vol)) { s64 wpos = (rl->lcn << vol->cluster_size_bits) + ofs; s64 wend = (rl->vcn << vol->cluster_size_bits) + ofs + to_write; u32 bsize = vol->cluster_size; /* Byte size needed to zero fill a cluster */ s64 rounding = ((wend + bsize - 1) & ~(s64)(bsize - 1)) - wend; /** * Zero fill to cluster boundary if we're writing at the * end of the attribute or into an ex-sparse cluster. * This will cause the kernel not to seek and read disk * blocks during write(2) to fill the end of the buffer * which increases write speed by 2-10 fold typically. * * This is done even for compressed files, because * data is generally first written uncompressed. */ if (rounding && ((wend == na->initialized_size) || (wend < (hole_end << vol->cluster_size_bits)))){ char *cb; rounding += to_write; cb = ntfs_malloc(rounding); if (!cb) goto err_out; memcpy(cb, b, to_write); memset(cb + to_write, 0, rounding - to_write); if (compressed) { written = ntfs_compressed_pwrite(na, rl, wpos, ofs, to_write, rounding, b, compressed_part, &update_from); } else { written = ntfs_pwrite(vol->dev, wpos, rounding, cb); if (written == rounding) written = to_write; } free(cb); } else { if (compressed) { written = ntfs_compressed_pwrite(na, rl, wpos, ofs, to_write, to_write, b, compressed_part, &update_from); } else written = ntfs_pwrite(vol->dev, wpos, to_write, b); } } else written = to_write; /* If everything ok, update progress counters and continue. */ if (written > 0) { total += written; count -= written; fullcount -= written; b = (const u8*)b + written; } if (written != to_write) { /* Partial write cannot be dealt with, stop there */ /* If the syscall was interrupted, try again. */ if (written == (s64)-1 && errno == EINTR) goto retry; if (!written) errno = EIO; goto rl_err_out; } compressed_part = 0; } done: if (ctx) ntfs_attr_put_search_ctx(ctx); /* * Update mapping pairs if needed. * For a compressed file, we try to make a partial update * of the mapping list. This makes a difference only if * inode extents were needed. */ updatemap = (compressed ? NAttrFullyMapped(na) != 0 : update_from != -1); if (updatemap) if (ntfs_attr_update_mapping_pairs(na, (update_from < 0 ? 0 : update_from))) { /* * FIXME: trying to recover by goto rl_err_out; * could cause driver hang by infinite looping. */ total = -1; goto out; } out: ntfs_log_leave("\n"); return total; rl_err_out: eo = errno; if (total) { if (need_to.undo_initialized_size) { if (pos + total > na->initialized_size) goto done; /* * TODO: Need to try to change initialized_size. If it * succeeds goto done, otherwise goto err_out. (AIA) */ goto err_out; } goto done; } errno = eo; err_out: eo = errno; if (need_to.undo_initialized_size) { int err; err = 0; if (!ctx) { ctx = ntfs_attr_get_search_ctx(na->ni, NULL); if (!ctx) err = 1; } else ntfs_attr_reinit_search_ctx(ctx); if (!err) { err = ntfs_attr_lookup(na->type, na->name, na->name_len, 0, 0, NULL, 0, ctx); if (!err) { na->initialized_size = old_initialized_size; ctx->attr->initialized_size = cpu_to_sle64( old_initialized_size); err = ntfs_mft_record_write(vol, ctx->ntfs_ino->mft_no, ctx->mrec); } } if (err) { /* * FIXME: At this stage could try to recover by filling * old_initialized_size -> new_initialized_size with * data or at least zeroes. (AIA) */ ntfs_log_error("Eeek! Failed to recover from error. " "Leaving metadata in inconsistent " "state! Run chkdsk!\n"); } } if (ctx) ntfs_attr_put_search_ctx(ctx); /* Update mapping pairs if needed. */ updatemap = (compressed ? NAttrFullyMapped(na) != 0 : update_from != -1); if (updatemap) ntfs_attr_update_mapping_pairs(na, 0); /* Restore original data_size if needed. */ if (need_to.undo_data_size && ntfs_attr_truncate(na, old_data_size)) ntfs_log_perror("Failed to restore data_size"); errno = eo; errno_set: total = -1; goto out; } int ntfs_attr_pclose(ntfs_attr *na) { s64 ofs; int failed; BOOL ok = TRUE; VCN update_from = -1; ntfs_volume *vol; ntfs_attr_search_ctx *ctx = NULL; runlist_element *rl; int eo; s64 hole; int compressed_part; BOOL compressed; ntfs_log_enter("Entering for inode 0x%llx, attr 0x%x.\n", na->ni->mft_no, na->type); if (!na || !na->ni || !na->ni->vol) { errno = EINVAL; ntfs_log_perror("%s", __FUNCTION__); goto errno_set; } vol = na->ni->vol; na->unused_runs = 0; compressed = (na->data_flags & ATTR_COMPRESSION_MASK) != const_cpu_to_le16(0); /* * Encrypted non-resident attributes are not supported. We return * access denied, which is what Windows NT4 does, too. */ if (NAttrEncrypted(na) && NAttrNonResident(na)) { errno = EACCES; goto errno_set; } /* If this is not a compressed attribute get out */ /* same if it is resident */ if (!compressed || !NAttrNonResident(na)) goto out; /* safety check : no recursion on close */ if (NAttrComprClosing(na)) { errno = EIO; ntfs_log_error("Bad ntfs_attr_pclose" " recursion on inode %lld\n", (long long)na->ni->mft_no); goto out; } NAttrSetComprClosing(na); /* * For a compressed attribute, we must be sure there are two * available entries, so reserve them before it gets too late. */ if (ntfs_attr_map_whole_runlist(na)) goto err_out; na->rl = ntfs_rl_extend(na,na->rl,2); if (!na->rl) goto err_out; na->unused_runs = 2; /* Find the runlist element containing the terminal vcn. */ rl = ntfs_attr_find_vcn(na, (na->initialized_size - 1) >> vol->cluster_size_bits); if (!rl) { /* * If the vcn is not present it is an out of bounds write. * However, we have already written the last byte uncompressed, * so getting this here must be an error of some kind. */ if (errno == ENOENT) { errno = EIO; ntfs_log_perror("%s: Failed to find VCN #5", __FUNCTION__); } goto err_out; } /* * Scatter the data from the linear data buffer to the volume. Note, a * partial final vcn is taken care of by the @count capping of write * length. */ compressed_part = 0; if (rl->lcn >= 0) { runlist_element *xrl; xrl = rl; do { xrl++; } while (xrl->lcn >= 0); compressed_part = (-xrl->length) & (na->compression_block_clusters - 1); } else if (rl->lcn == (LCN)LCN_HOLE) { if (rl->length < na->compression_block_clusters) compressed_part = na->compression_block_clusters - rl->length; else compressed_part = na->compression_block_clusters; } /* done, if the last block set was compressed */ if (compressed_part) goto out; ofs = na->initialized_size - (rl->vcn << vol->cluster_size_bits); if (rl->lcn == LCN_RL_NOT_MAPPED) { rl = ntfs_attr_find_vcn(na, rl->vcn); if (!rl) { if (errno == ENOENT) { errno = EIO; ntfs_log_perror("%s: Failed to find VCN" " #6", __FUNCTION__); } goto rl_err_out; } /* Needed for case when runs merged. */ ofs = na->initialized_size - (rl->vcn << vol->cluster_size_bits); } if (!rl->length) { errno = EIO; ntfs_log_perror("%s: Zero run length", __FUNCTION__); goto rl_err_out; } if (rl->lcn < (LCN)0) { hole = rl->vcn + rl->length; if (rl->lcn != (LCN)LCN_HOLE) { errno = EIO; ntfs_log_perror("%s: Unexpected LCN (%lld)", __FUNCTION__, (long long)rl->lcn); goto rl_err_out; } if (ntfs_attr_fill_hole(na, (s64)0, &ofs, &rl, &update_from)) goto err_out; } while (rl->length && (ofs >= (rl->length << vol->cluster_size_bits))) { ofs -= rl->length << vol->cluster_size_bits; rl++; } retry: failed = 0; if (update_from < 0) update_from = 0; if (!NVolReadOnly(vol)) { failed = ntfs_compressed_close(na, rl, ofs, &update_from); #if CACHE_NIDATA_SIZE if (na->ni->mrec->flags & MFT_RECORD_IS_DIRECTORY ? na->type == AT_INDEX_ROOT && na->name == NTFS_INDEX_I30 : na->type == AT_DATA && na->name == AT_UNNAMED) { na->ni->data_size = na->data_size; na->ni->allocated_size = na->compressed_size; set_nino_flag(na->ni,KnownSize); } #endif } if (failed) { /* If the syscall was interrupted, try again. */ if (errno == EINTR) goto retry; else goto rl_err_out; } if (ctx) ntfs_attr_put_search_ctx(ctx); /* Update mapping pairs if needed. */ if (NAttrFullyMapped(na)) if (ntfs_attr_update_mapping_pairs(na, update_from)) { /* * FIXME: trying to recover by goto rl_err_out; * could cause driver hang by infinite looping. */ ok = FALSE; goto out; } out: ntfs_log_leave("\n"); return (!ok); rl_err_out: /* * need not restore old sizes, only compressed_size * can have changed. It has been set according to * the current runlist while updating the mapping pairs, * and must be kept consistent with the runlists. */ err_out: eo = errno; if (ctx) ntfs_attr_put_search_ctx(ctx); /* Update mapping pairs if needed. */ if (NAttrFullyMapped(na)) ntfs_attr_update_mapping_pairs(na, 0); errno = eo; errno_set: ok = FALSE; goto out; } /** * ntfs_attr_mst_pread - multi sector transfer protected ntfs attribute read * @na: multi sector transfer protected ntfs attribute to read from * @pos: byte position in the attribute to begin reading from * @bk_cnt: number of mst protected blocks to read * @bk_size: size of each mst protected block in bytes * @dst: output data buffer * * This function will read @bk_cnt blocks of size @bk_size bytes each starting * at offset @pos from the ntfs attribute @na into the data buffer @b. * * On success, the multi sector transfer fixups are applied and the number of * read blocks is returned. If this number is lower than @bk_cnt this means * that the read has either reached end of attribute or that an error was * encountered during the read so that the read is partial. 0 means end of * attribute or nothing to read (also return 0 when @bk_cnt or @bk_size are 0). * * On error and nothing has been read, return -1 with errno set appropriately * to the return code of ntfs_attr_pread() or to EINVAL in case of invalid * arguments. * * NOTE: If an incomplete multi sector transfer is detected the magic is * changed to BAAD but no error is returned, i.e. it is possible that any of * the returned blocks have multi sector transfer errors. This should be * detected by the caller by checking each block with is_baad_recordp(&block). * The reasoning is that we want to fixup as many blocks as possible and we * want to return even bad ones to the caller so, e.g. in case of ntfsck, the * errors can be repaired. */ s64 ntfs_attr_mst_pread(ntfs_attr *na, const s64 pos, const s64 bk_cnt, const u32 bk_size, void *dst) { s64 br; u8 *end; ntfs_log_trace("Entering for inode 0x%llx, attr type 0x%x, pos 0x%llx.\n", (unsigned long long)na->ni->mft_no, na->type, (long long)pos); if (bk_cnt < 0 || bk_size % NTFS_BLOCK_SIZE) { errno = EINVAL; ntfs_log_perror("%s", __FUNCTION__); return -1; } br = ntfs_attr_pread(na, pos, bk_cnt * bk_size, dst); if (br <= 0) return br; br /= bk_size; for (end = (u8*)dst + br * bk_size; (u8*)dst < end; dst = (u8*)dst + bk_size) ntfs_mst_post_read_fixup((NTFS_RECORD*)dst, bk_size); /* Finally, return the number of blocks read. */ return br; } /** * ntfs_attr_mst_pwrite - multi sector transfer protected ntfs attribute write * @na: multi sector transfer protected ntfs attribute to write to * @pos: position in the attribute to write to * @bk_cnt: number of mst protected blocks to write * @bk_size: size of each mst protected block in bytes * @src: data buffer to write to disk * * This function will write @bk_cnt blocks of size @bk_size bytes each from * data buffer @b to multi sector transfer (mst) protected ntfs attribute @na * at position @pos. * * On success, return the number of successfully written blocks. If this number * is lower than @bk_cnt this means that an error was encountered during the * write so that the write is partial. 0 means nothing was written (also * return 0 when @bk_cnt or @bk_size are 0). * * On error and nothing has been written, return -1 with errno set * appropriately to the return code of ntfs_attr_pwrite(), or to EINVAL in case * of invalid arguments. * * NOTE: We mst protect the data, write it, then mst deprotect it using a quick * deprotect algorithm (no checking). This saves us from making a copy before * the write and at the same time causes the usn to be incremented in the * buffer. This conceptually fits in better with the idea that cached data is * always deprotected and protection is performed when the data is actually * going to hit the disk and the cache is immediately deprotected again * simulating an mst read on the written data. This way cache coherency is * achieved. */ s64 ntfs_attr_mst_pwrite(ntfs_attr *na, const s64 pos, s64 bk_cnt, const u32 bk_size, void *src) { s64 written, i; ntfs_log_trace("Entering for inode 0x%llx, attr type 0x%x, pos 0x%llx.\n", (unsigned long long)na->ni->mft_no, na->type, (long long)pos); if (bk_cnt < 0 || bk_size % NTFS_BLOCK_SIZE) { errno = EINVAL; return -1; } if (!bk_cnt) return 0; /* Prepare data for writing. */ for (i = 0; i < bk_cnt; ++i) { int err; err = ntfs_mst_pre_write_fixup((NTFS_RECORD*) ((u8*)src + i * bk_size), bk_size); if (err < 0) { /* Abort write at this position. */ ntfs_log_perror("%s #1", __FUNCTION__); if (!i) return err; bk_cnt = i; break; } } /* Write the prepared data. */ written = ntfs_attr_pwrite(na, pos, bk_cnt * bk_size, src); if (written <= 0) { ntfs_log_perror("%s: written=%lld", __FUNCTION__, (long long)written); } /* Quickly deprotect the data again. */ for (i = 0; i < bk_cnt; ++i) ntfs_mst_post_write_fixup((NTFS_RECORD*)((u8*)src + i * bk_size)); if (written <= 0) return written; /* Finally, return the number of complete blocks written. */ return written / bk_size; } /** * ntfs_attr_find - find (next) attribute in mft record * @type: attribute type to find * @name: attribute name to find (optional, i.e. NULL means don't care) * @name_len: attribute name length (only needed if @name present) * @ic: IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present) * @val: attribute value to find (optional, resident attributes only) * @val_len: attribute value length * @ctx: search context with mft record and attribute to search from * * You shouldn't need to call this function directly. Use lookup_attr() instead. * * ntfs_attr_find() takes a search context @ctx as parameter and searches the * mft record specified by @ctx->mrec, beginning at @ctx->attr, for an * attribute of @type, optionally @name and @val. If found, ntfs_attr_find() * returns 0 and @ctx->attr will point to the found attribute. * * If not found, ntfs_attr_find() returns -1, with errno set to ENOENT and * @ctx->attr will point to the attribute before which the attribute being * searched for would need to be inserted if such an action were to be desired. * * On actual error, ntfs_attr_find() returns -1 with errno set to the error * code but not to ENOENT. In this case @ctx->attr is undefined and in * particular do not rely on it not changing. * * If @ctx->is_first is TRUE, the search begins with @ctx->attr itself. If it * is FALSE, the search begins after @ctx->attr. * * If @type is AT_UNUSED, return the first found attribute, i.e. one can * enumerate all attributes by setting @type to AT_UNUSED and then calling * ntfs_attr_find() repeatedly until it returns -1 with errno set to ENOENT to * indicate that there are no more entries. During the enumeration, each * successful call of ntfs_attr_find() will return the next attribute in the * mft record @ctx->mrec. * * If @type is AT_END, seek to the end and return -1 with errno set to ENOENT. * AT_END is not a valid attribute, its length is zero for example, thus it is * safer to return error instead of success in this case. This also allows us * to interoperate cleanly with ntfs_external_attr_find(). * * If @name is AT_UNNAMED search for an unnamed attribute. If @name is present * but not AT_UNNAMED search for a named attribute matching @name. Otherwise, * match both named and unnamed attributes. * * If @ic is IGNORE_CASE, the @name comparison is not case sensitive and * @ctx->ntfs_ino must be set to the ntfs inode to which the mft record * @ctx->mrec belongs. This is so we can get at the ntfs volume and hence at * the upcase table. If @ic is CASE_SENSITIVE, the comparison is case * sensitive. When @name is present, @name_len is the @name length in Unicode * characters. * * If @name is not present (NULL), we assume that the unnamed attribute is * being searched for. * * Finally, the resident attribute value @val is looked for, if present. * If @val is not present (NULL), @val_len is ignored. * * ntfs_attr_find() only searches the specified mft record and it ignores the * presence of an attribute list attribute (unless it is the one being searched * for, obviously). If you need to take attribute lists into consideration, use * ntfs_attr_lookup() instead (see below). This also means that you cannot use * ntfs_attr_find() to search for extent records of non-resident attributes, as * extents with lowest_vcn != 0 are usually described by the attribute list * attribute only. - Note that it is possible that the first extent is only in * the attribute list while the last extent is in the base mft record, so don't * rely on being able to find the first extent in the base mft record. * * Warning: Never use @val when looking for attribute types which can be * non-resident as this most likely will result in a crash! */ static int ntfs_attr_find(const ATTR_TYPES type, const ntfschar *name, const u32 name_len, const IGNORE_CASE_BOOL ic, const u8 *val, const u32 val_len, ntfs_attr_search_ctx *ctx) { ATTR_RECORD *a; ntfs_volume *vol; ntfschar *upcase; u32 upcase_len; ntfs_log_trace("attribute type 0x%x.\n", type); if (ctx->ntfs_ino) { vol = ctx->ntfs_ino->vol; upcase = vol->upcase; upcase_len = vol->upcase_len; } else { if (name && name != AT_UNNAMED) { errno = EINVAL; ntfs_log_perror("%s", __FUNCTION__); return -1; } vol = NULL; upcase = NULL; upcase_len = 0; } /* * Iterate over attributes in mft record starting at @ctx->attr, or the * attribute following that, if @ctx->is_first is TRUE. */ if (ctx->is_first) { a = ctx->attr; ctx->is_first = FALSE; } else a = (ATTR_RECORD*)((char*)ctx->attr + le32_to_cpu(ctx->attr->length)); for (;; a = (ATTR_RECORD*)((char*)a + le32_to_cpu(a->length))) { if (p2n(a) < p2n(ctx->mrec) || (char*)a > (char*)ctx->mrec + le32_to_cpu(ctx->mrec->bytes_allocated)) break; ctx->attr = a; if (((type != AT_UNUSED) && (le32_to_cpu(a->type) > le32_to_cpu(type))) || (a->type == AT_END)) { errno = ENOENT; return -1; } if (!a->length) break; /* If this is an enumeration return this attribute. */ if (type == AT_UNUSED) return 0; if (a->type != type) continue; /* * If @name is AT_UNNAMED we want an unnamed attribute. * If @name is present, compare the two names. * Otherwise, match any attribute. */ if (name == AT_UNNAMED) { /* The search failed if the found attribute is named. */ if (a->name_length) { errno = ENOENT; return -1; } } else { register int rc; if (name && ((rc = ntfs_names_full_collate(name, name_len, (ntfschar*)((char*)a + le16_to_cpu(a->name_offset)), a->name_length, ic, upcase, upcase_len)))) { /* * If @name collates before a->name, * there is no matching attribute. */ if (rc < 0) { errno = ENOENT; return -1; } /* If the strings are not equal, continue search. */ continue; } } /* * The names match or @name not present and attribute is * unnamed. If no @val specified, we have found the attribute * and are done. */ if (!val) return 0; /* @val is present; compare values. */ else { register int rc; rc = memcmp(val, (char*)a +le16_to_cpu(a->value_offset), min(val_len, le32_to_cpu(a->value_length))); /* * If @val collates before the current attribute's * value, there is no matching attribute. */ if (!rc) { register u32 avl; avl = le32_to_cpu(a->value_length); if (val_len == avl) return 0; if (val_len < avl) { errno = ENOENT; return -1; } } else if (rc < 0) { errno = ENOENT; return -1; } } } errno = EIO; ntfs_log_perror("%s: Corrupt inode (%lld)", __FUNCTION__, ctx->ntfs_ino ? (long long)ctx->ntfs_ino->mft_no : -1); return -1; } void ntfs_attr_name_free(char **name) { if (*name) { free(*name); *name = NULL; } } char *ntfs_attr_name_get(const ntfschar *uname, const int uname_len) { char *name = NULL; int name_len; name_len = ntfs_ucstombs(uname, uname_len, &name, 0); if (name_len < 0) { ntfs_log_perror("ntfs_ucstombs"); return NULL; } else if (name_len > 0) return name; ntfs_attr_name_free(&name); return NULL; } /** * ntfs_external_attr_find - find an attribute in the attribute list of an inode * @type: attribute type to find * @name: attribute name to find (optional, i.e. NULL means don't care) * @name_len: attribute name length (only needed if @name present) * @ic: IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present) * @lowest_vcn: lowest vcn to find (optional, non-resident attributes only) * @val: attribute value to find (optional, resident attributes only) * @val_len: attribute value length * @ctx: search context with mft record and attribute to search from * * You shouldn't need to call this function directly. Use ntfs_attr_lookup() * instead. * * Find an attribute by searching the attribute list for the corresponding * attribute list entry. Having found the entry, map the mft record for read * if the attribute is in a different mft record/inode, find the attribute in * there and return it. * * If @type is AT_UNUSED, return the first found attribute, i.e. one can * enumerate all attributes by setting @type to AT_UNUSED and then calling * ntfs_external_attr_find() repeatedly until it returns -1 with errno set to * ENOENT to indicate that there are no more entries. During the enumeration, * each successful call of ntfs_external_attr_find() will return the next * attribute described by the attribute list of the base mft record described * by the search context @ctx. * * If @type is AT_END, seek to the end of the base mft record ignoring the * attribute list completely and return -1 with errno set to ENOENT. AT_END is * not a valid attribute, its length is zero for example, thus it is safer to * return error instead of success in this case. * * If @name is AT_UNNAMED search for an unnamed attribute. If @name is present * but not AT_UNNAMED search for a named attribute matching @name. Otherwise, * match both named and unnamed attributes. * * On first search @ctx->ntfs_ino must be the inode of the base mft record and * @ctx must have been obtained from a call to ntfs_attr_get_search_ctx(). * On subsequent calls, @ctx->ntfs_ino can be any extent inode, too * (@ctx->base_ntfs_ino is then the base inode). * * After finishing with the attribute/mft record you need to call * ntfs_attr_put_search_ctx() to cleanup the search context (unmapping any * mapped extent inodes, etc). * * Return 0 if the search was successful and -1 if not, with errno set to the * error code. * * On success, @ctx->attr is the found attribute, it is in mft record * @ctx->mrec, and @ctx->al_entry is the attribute list entry for this * attribute with @ctx->base_* being the base mft record to which @ctx->attr * belongs. * * On error ENOENT, i.e. attribute not found, @ctx->attr is set to the * attribute which collates just after the attribute being searched for in the * base ntfs inode, i.e. if one wants to add the attribute to the mft record * this is the correct place to insert it into, and if there is not enough * space, the attribute should be placed in an extent mft record. * @ctx->al_entry points to the position within @ctx->base_ntfs_ino->attr_list * at which the new attribute's attribute list entry should be inserted. The * other @ctx fields, base_ntfs_ino, base_mrec, and base_attr are set to NULL. * The only exception to this is when @type is AT_END, in which case * @ctx->al_entry is set to NULL also (see above). * * The following error codes are defined: * ENOENT Attribute not found, not an error as such. * EINVAL Invalid arguments. * EIO I/O error or corrupt data structures found. * ENOMEM Not enough memory to allocate necessary buffers. */ static int ntfs_external_attr_find(ATTR_TYPES type, const ntfschar *name, const u32 name_len, const IGNORE_CASE_BOOL ic, const VCN lowest_vcn, const u8 *val, const u32 val_len, ntfs_attr_search_ctx *ctx) { ntfs_inode *base_ni, *ni; ntfs_volume *vol; ATTR_LIST_ENTRY *al_entry, *next_al_entry; u8 *al_start, *al_end; ATTR_RECORD *a; ntfschar *al_name; u32 al_name_len; BOOL is_first_search = FALSE; ni = ctx->ntfs_ino; base_ni = ctx->base_ntfs_ino; ntfs_log_trace("Entering for inode %lld, attribute type 0x%x.\n", (unsigned long long)ni->mft_no, type); if (!base_ni) { /* First call happens with the base mft record. */ base_ni = ctx->base_ntfs_ino = ctx->ntfs_ino; ctx->base_mrec = ctx->mrec; } if (ni == base_ni) ctx->base_attr = ctx->attr; if (type == AT_END) goto not_found; vol = base_ni->vol; al_start = base_ni->attr_list; al_end = al_start + base_ni->attr_list_size; if (!ctx->al_entry) { ctx->al_entry = (ATTR_LIST_ENTRY*)al_start; is_first_search = TRUE; } /* * Iterate over entries in attribute list starting at @ctx->al_entry, * or the entry following that, if @ctx->is_first is TRUE. */ if (ctx->is_first) { al_entry = ctx->al_entry; ctx->is_first = FALSE; /* * If an enumeration and the first attribute is higher than * the attribute list itself, need to return the attribute list * attribute. */ if ((type == AT_UNUSED) && is_first_search && le32_to_cpu(al_entry->type) > le32_to_cpu(AT_ATTRIBUTE_LIST)) goto find_attr_list_attr; } else { al_entry = (ATTR_LIST_ENTRY*)((char*)ctx->al_entry + le16_to_cpu(ctx->al_entry->length)); /* * If this is an enumeration and the attribute list attribute * is the next one in the enumeration sequence, just return the * attribute list attribute from the base mft record as it is * not listed in the attribute list itself. */ if ((type == AT_UNUSED) && le32_to_cpu(ctx->al_entry->type) < le32_to_cpu(AT_ATTRIBUTE_LIST) && le32_to_cpu(al_entry->type) > le32_to_cpu(AT_ATTRIBUTE_LIST)) { int rc; find_attr_list_attr: /* Check for bogus calls. */ if (name || name_len || val || val_len || lowest_vcn) { errno = EINVAL; ntfs_log_perror("%s", __FUNCTION__); return -1; } /* We want the base record. */ ctx->ntfs_ino = base_ni; ctx->mrec = ctx->base_mrec; ctx->is_first = TRUE; /* Sanity checks are performed elsewhere. */ ctx->attr = (ATTR_RECORD*)((u8*)ctx->mrec + le16_to_cpu(ctx->mrec->attrs_offset)); /* Find the attribute list attribute. */ rc = ntfs_attr_find(AT_ATTRIBUTE_LIST, NULL, 0, IGNORE_CASE, NULL, 0, ctx); /* * Setup the search context so the correct * attribute is returned next time round. */ ctx->al_entry = al_entry; ctx->is_first = TRUE; /* Got it. Done. */ if (!rc) return 0; /* Error! If other than not found return it. */ if (errno != ENOENT) return rc; /* Not found?!? Absurd! */ errno = EIO; ntfs_log_error("Attribute list wasn't found"); return -1; } } for (;; al_entry = next_al_entry) { /* Out of bounds check. */ if ((u8*)al_entry < base_ni->attr_list || (u8*)al_entry > al_end) break; /* Inode is corrupt. */ ctx->al_entry = al_entry; /* Catch the end of the attribute list. */ if ((u8*)al_entry == al_end) goto not_found; if (!al_entry->length) break; if ((u8*)al_entry + 6 > al_end || (u8*)al_entry + le16_to_cpu(al_entry->length) > al_end) break; next_al_entry = (ATTR_LIST_ENTRY*)((u8*)al_entry + le16_to_cpu(al_entry->length)); if (type != AT_UNUSED) { if (le32_to_cpu(al_entry->type) > le32_to_cpu(type)) goto not_found; if (type != al_entry->type) continue; } al_name_len = al_entry->name_length; al_name = (ntfschar*)((u8*)al_entry + al_entry->name_offset); /* * If !@type we want the attribute represented by this * attribute list entry. */ if (type == AT_UNUSED) goto is_enumeration; /* * If @name is AT_UNNAMED we want an unnamed attribute. * If @name is present, compare the two names. * Otherwise, match any attribute. */ if (name == AT_UNNAMED) { if (al_name_len) goto not_found; } else { int rc; if (name && ((rc = ntfs_names_full_collate(name, name_len, al_name, al_name_len, ic, vol->upcase, vol->upcase_len)))) { /* * If @name collates before al_name, * there is no matching attribute. */ if (rc < 0) goto not_found; /* If the strings are not equal, continue search. */ continue; } } /* * The names match or @name not present and attribute is * unnamed. Now check @lowest_vcn. Continue search if the * next attribute list entry still fits @lowest_vcn. Otherwise * we have reached the right one or the search has failed. */ if (lowest_vcn && (u8*)next_al_entry >= al_start && (u8*)next_al_entry + 6 < al_end && (u8*)next_al_entry + le16_to_cpu( next_al_entry->length) <= al_end && sle64_to_cpu(next_al_entry->lowest_vcn) <= lowest_vcn && next_al_entry->type == al_entry->type && next_al_entry->name_length == al_name_len && ntfs_names_are_equal((ntfschar*)((char*) next_al_entry + next_al_entry->name_offset), next_al_entry->name_length, al_name, al_name_len, CASE_SENSITIVE, vol->upcase, vol->upcase_len)) continue; is_enumeration: if (MREF_LE(al_entry->mft_reference) == ni->mft_no) { if (MSEQNO_LE(al_entry->mft_reference) != le16_to_cpu( ni->mrec->sequence_number)) { ntfs_log_error("Found stale mft reference in " "attribute list!\n"); break; } } else { /* Mft references do not match. */ /* Do we want the base record back? */ if (MREF_LE(al_entry->mft_reference) == base_ni->mft_no) { ni = ctx->ntfs_ino = base_ni; ctx->mrec = ctx->base_mrec; } else { /* We want an extent record. */ ni = ntfs_extent_inode_open(base_ni, al_entry->mft_reference); if (!ni) break; ctx->ntfs_ino = ni; ctx->mrec = ni->mrec; } } a = ctx->attr = (ATTR_RECORD*)((char*)ctx->mrec + le16_to_cpu(ctx->mrec->attrs_offset)); /* * ctx->ntfs_ino, ctx->mrec, and ctx->attr now point to the * mft record containing the attribute represented by the * current al_entry. * * We could call into ntfs_attr_find() to find the right * attribute in this mft record but this would be less * efficient and not quite accurate as ntfs_attr_find() ignores * the attribute instance numbers for example which become * important when one plays with attribute lists. Also, because * a proper match has been found in the attribute list entry * above, the comparison can now be optimized. So it is worth * re-implementing a simplified ntfs_attr_find() here. * * Use a manual loop so we can still use break and continue * with the same meanings as above. */ do_next_attr_loop: if ((char*)a < (char*)ctx->mrec || (char*)a > (char*)ctx->mrec + le32_to_cpu(ctx->mrec->bytes_allocated)) break; if (a->type == AT_END) continue; if (!a->length) break; if (al_entry->instance != a->instance) goto do_next_attr; /* * If the type and/or the name are/is mismatched between the * attribute list entry and the attribute record, there is * corruption so we break and return error EIO. */ if (al_entry->type != a->type) break; if (!ntfs_names_are_equal((ntfschar*)((char*)a + le16_to_cpu(a->name_offset)), a->name_length, al_name, al_name_len, CASE_SENSITIVE, vol->upcase, vol->upcase_len)) break; ctx->attr = a; /* * If no @val specified or @val specified and it matches, we * have found it! Also, if !@type, it is an enumeration, so we * want the current attribute. */ if ((type == AT_UNUSED) || !val || (!a->non_resident && le32_to_cpu(a->value_length) == val_len && !memcmp((char*)a + le16_to_cpu(a->value_offset), val, val_len))) { return 0; } do_next_attr: /* Proceed to the next attribute in the current mft record. */ a = (ATTR_RECORD*)((char*)a + le32_to_cpu(a->length)); goto do_next_attr_loop; } if (ni != base_ni) { ctx->ntfs_ino = base_ni; ctx->mrec = ctx->base_mrec; ctx->attr = ctx->base_attr; } errno = EIO; ntfs_log_perror("Inode is corrupt (%lld)", (long long)base_ni->mft_no); return -1; not_found: /* * If we were looking for AT_END or we were enumerating and reached the * end, we reset the search context @ctx and use ntfs_attr_find() to * seek to the end of the base mft record. */ if (type == AT_UNUSED || type == AT_END) { ntfs_attr_reinit_search_ctx(ctx); return ntfs_attr_find(AT_END, name, name_len, ic, val, val_len, ctx); } /* * The attribute wasn't found. Before we return, we want to ensure * @ctx->mrec and @ctx->attr indicate the position at which the * attribute should be inserted in the base mft record. Since we also * want to preserve @ctx->al_entry we cannot reinitialize the search * context using ntfs_attr_reinit_search_ctx() as this would set * @ctx->al_entry to NULL. Thus we do the necessary bits manually (see * ntfs_attr_init_search_ctx() below). Note, we _only_ preserve * @ctx->al_entry as the remaining fields (base_*) are identical to * their non base_ counterparts and we cannot set @ctx->base_attr * correctly yet as we do not know what @ctx->attr will be set to by * the call to ntfs_attr_find() below. */ ctx->mrec = ctx->base_mrec; ctx->attr = (ATTR_RECORD*)((u8*)ctx->mrec + le16_to_cpu(ctx->mrec->attrs_offset)); ctx->is_first = TRUE; ctx->ntfs_ino = ctx->base_ntfs_ino; ctx->base_ntfs_ino = NULL; ctx->base_mrec = NULL; ctx->base_attr = NULL; /* * In case there are multiple matches in the base mft record, need to * keep enumerating until we get an attribute not found response (or * another error), otherwise we would keep returning the same attribute * over and over again and all programs using us for enumeration would * lock up in a tight loop. */ { int ret; do { ret = ntfs_attr_find(type, name, name_len, ic, val, val_len, ctx); } while (!ret); return ret; } } /** * ntfs_attr_lookup - find an attribute in an ntfs inode * @type: attribute type to find * @name: attribute name to find (optional, i.e. NULL means don't care) * @name_len: attribute name length (only needed if @name present) * @ic: IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present) * @lowest_vcn: lowest vcn to find (optional, non-resident attributes only) * @val: attribute value to find (optional, resident attributes only) * @val_len: attribute value length * @ctx: search context with mft record and attribute to search from * * Find an attribute in an ntfs inode. On first search @ctx->ntfs_ino must * be the base mft record and @ctx must have been obtained from a call to * ntfs_attr_get_search_ctx(). * * This function transparently handles attribute lists and @ctx is used to * continue searches where they were left off at. * * If @type is AT_UNUSED, return the first found attribute, i.e. one can * enumerate all attributes by setting @type to AT_UNUSED and then calling * ntfs_attr_lookup() repeatedly until it returns -1 with errno set to ENOENT * to indicate that there are no more entries. During the enumeration, each * successful call of ntfs_attr_lookup() will return the next attribute, with * the current attribute being described by the search context @ctx. * * If @type is AT_END, seek to the end of the base mft record ignoring the * attribute list completely and return -1 with errno set to ENOENT. AT_END is * not a valid attribute, its length is zero for example, thus it is safer to * return error instead of success in this case. It should never be needed to * do this, but we implement the functionality because it allows for simpler * code inside ntfs_external_attr_find(). * * If @name is AT_UNNAMED search for an unnamed attribute. If @name is present * but not AT_UNNAMED search for a named attribute matching @name. Otherwise, * match both named and unnamed attributes. * * After finishing with the attribute/mft record you need to call * ntfs_attr_put_search_ctx() to cleanup the search context (unmapping any * mapped extent inodes, etc). * * Return 0 if the search was successful and -1 if not, with errno set to the * error code. * * On success, @ctx->attr is the found attribute, it is in mft record * @ctx->mrec, and @ctx->al_entry is the attribute list entry for this * attribute with @ctx->base_* being the base mft record to which @ctx->attr * belongs. If no attribute list attribute is present @ctx->al_entry and * @ctx->base_* are NULL. * * On error ENOENT, i.e. attribute not found, @ctx->attr is set to the * attribute which collates just after the attribute being searched for in the * base ntfs inode, i.e. if one wants to add the attribute to the mft record * this is the correct place to insert it into, and if there is not enough * space, the attribute should be placed in an extent mft record. * @ctx->al_entry points to the position within @ctx->base_ntfs_ino->attr_list * at which the new attribute's attribute list entry should be inserted. The * other @ctx fields, base_ntfs_ino, base_mrec, and base_attr are set to NULL. * The only exception to this is when @type is AT_END, in which case * @ctx->al_entry is set to NULL also (see above). * * * The following error codes are defined: * ENOENT Attribute not found, not an error as such. * EINVAL Invalid arguments. * EIO I/O error or corrupt data structures found. * ENOMEM Not enough memory to allocate necessary buffers. */ int ntfs_attr_lookup(const ATTR_TYPES type, const ntfschar *name, const u32 name_len, const IGNORE_CASE_BOOL ic, const VCN lowest_vcn, const u8 *val, const u32 val_len, ntfs_attr_search_ctx *ctx) { ntfs_volume *vol; ntfs_inode *base_ni; int ret = -1; ntfs_log_enter("Entering for attribute type 0x%x\n", type); if (!ctx || !ctx->mrec || !ctx->attr || (name && name != AT_UNNAMED && (!ctx->ntfs_ino || !(vol = ctx->ntfs_ino->vol) || !vol->upcase || !vol->upcase_len))) { errno = EINVAL; ntfs_log_perror("%s", __FUNCTION__); goto out; } if (ctx->base_ntfs_ino) base_ni = ctx->base_ntfs_ino; else base_ni = ctx->ntfs_ino; if (!base_ni || !NInoAttrList(base_ni) || type == AT_ATTRIBUTE_LIST) ret = ntfs_attr_find(type, name, name_len, ic, val, val_len, ctx); else ret = ntfs_external_attr_find(type, name, name_len, ic, lowest_vcn, val, val_len, ctx); out: ntfs_log_leave("\n"); return ret; } /** * ntfs_attr_position - find given or next attribute type in an ntfs inode * @type: attribute type to start lookup * @ctx: search context with mft record and attribute to search from * * Find an attribute type in an ntfs inode or the next attribute which is not * the AT_END attribute. Please see more details at ntfs_attr_lookup. * * Return 0 if the search was successful and -1 if not, with errno set to the * error code. * * The following error codes are defined: * EINVAL Invalid arguments. * EIO I/O error or corrupt data structures found. * ENOMEM Not enough memory to allocate necessary buffers. * ENOSPC No attribute was found after 'type', only AT_END. */ int ntfs_attr_position(const ATTR_TYPES type, ntfs_attr_search_ctx *ctx) { if (ntfs_attr_lookup(type, NULL, 0, CASE_SENSITIVE, 0, NULL, 0, ctx)) { if (errno != ENOENT) return -1; if (ctx->attr->type == AT_END) { errno = ENOSPC; return -1; } } return 0; } /** * ntfs_attr_init_search_ctx - initialize an attribute search context * @ctx: attribute search context to initialize * @ni: ntfs inode with which to initialize the search context * @mrec: mft record with which to initialize the search context * * Initialize the attribute search context @ctx with @ni and @mrec. */ static void ntfs_attr_init_search_ctx(ntfs_attr_search_ctx *ctx, ntfs_inode *ni, MFT_RECORD *mrec) { if (!mrec) mrec = ni->mrec; ctx->mrec = mrec; /* Sanity checks are performed elsewhere. */ ctx->attr = (ATTR_RECORD*)((u8*)mrec + le16_to_cpu(mrec->attrs_offset)); ctx->is_first = TRUE; ctx->ntfs_ino = ni; ctx->al_entry = NULL; ctx->base_ntfs_ino = NULL; ctx->base_mrec = NULL; ctx->base_attr = NULL; } /** * ntfs_attr_reinit_search_ctx - reinitialize an attribute search context * @ctx: attribute search context to reinitialize * * Reinitialize the attribute search context @ctx. * * This is used when a search for a new attribute is being started to reset * the search context to the beginning. */ void ntfs_attr_reinit_search_ctx(ntfs_attr_search_ctx *ctx) { if (!ctx->base_ntfs_ino) { /* No attribute list. */ ctx->is_first = TRUE; /* Sanity checks are performed elsewhere. */ ctx->attr = (ATTR_RECORD*)((u8*)ctx->mrec + le16_to_cpu(ctx->mrec->attrs_offset)); /* * This needs resetting due to ntfs_external_attr_find() which * can leave it set despite having zeroed ctx->base_ntfs_ino. */ ctx->al_entry = NULL; return; } /* Attribute list. */ ntfs_attr_init_search_ctx(ctx, ctx->base_ntfs_ino, ctx->base_mrec); return; } /** * ntfs_attr_get_search_ctx - allocate/initialize a new attribute search context * @ni: ntfs inode with which to initialize the search context * @mrec: mft record with which to initialize the search context * * Allocate a new attribute search context, initialize it with @ni and @mrec, * and return it. Return NULL on error with errno set. * * @mrec can be NULL, in which case the mft record is taken from @ni. * * Note: For low level utilities which know what they are doing we allow @ni to * be NULL and @mrec to be set. Do NOT do this unless you understand the * implications!!! For example it is no longer safe to call ntfs_attr_lookup(). */ ntfs_attr_search_ctx *ntfs_attr_get_search_ctx(ntfs_inode *ni, MFT_RECORD *mrec) { ntfs_attr_search_ctx *ctx; if (!ni && !mrec) { errno = EINVAL; ntfs_log_perror("NULL arguments"); return NULL; } ctx = ntfs_malloc(sizeof(ntfs_attr_search_ctx)); if (ctx) ntfs_attr_init_search_ctx(ctx, ni, mrec); return ctx; } /** * ntfs_attr_put_search_ctx - release an attribute search context * @ctx: attribute search context to free * * Release the attribute search context @ctx. */ void ntfs_attr_put_search_ctx(ntfs_attr_search_ctx *ctx) { // NOTE: save errno if it could change and function stays void! free(ctx); } /** * ntfs_attr_find_in_attrdef - find an attribute in the $AttrDef system file * @vol: ntfs volume to which the attribute belongs * @type: attribute type which to find * * Search for the attribute definition record corresponding to the attribute * @type in the $AttrDef system file. * * Return the attribute type definition record if found and NULL if not found * or an error occurred. On error the error code is stored in errno. The * following error codes are defined: * ENOENT - The attribute @type is not specified in $AttrDef. * EINVAL - Invalid parameters (e.g. @vol is not valid). */ ATTR_DEF *ntfs_attr_find_in_attrdef(const ntfs_volume *vol, const ATTR_TYPES type) { ATTR_DEF *ad; if (!vol || !vol->attrdef || !type) { errno = EINVAL; ntfs_log_perror("%s: type=%d", __FUNCTION__, type); return NULL; } for (ad = vol->attrdef; (u8*)ad - (u8*)vol->attrdef < vol->attrdef_len && ad->type; ++ad) { /* We haven't found it yet, carry on searching. */ if (le32_to_cpu(ad->type) < le32_to_cpu(type)) continue; /* We found the attribute; return it. */ if (ad->type == type) return ad; /* We have gone too far already. No point in continuing. */ break; } errno = ENOENT; ntfs_log_perror("%s: type=%d", __FUNCTION__, type); return NULL; } /** * ntfs_attr_size_bounds_check - check a size of an attribute type for validity * @vol: ntfs volume to which the attribute belongs * @type: attribute type which to check * @size: size which to check * * Check whether the @size in bytes is valid for an attribute of @type on the * ntfs volume @vol. This information is obtained from $AttrDef system file. * * Return 0 if valid and -1 if not valid or an error occurred. On error the * error code is stored in errno. The following error codes are defined: * ERANGE - @size is not valid for the attribute @type. * ENOENT - The attribute @type is not specified in $AttrDef. * EINVAL - Invalid parameters (e.g. @size is < 0 or @vol is not valid). */ int ntfs_attr_size_bounds_check(const ntfs_volume *vol, const ATTR_TYPES type, const s64 size) { ATTR_DEF *ad; s64 min_size, max_size; if (size < 0) { errno = EINVAL; ntfs_log_perror("%s: size=%lld", __FUNCTION__, (long long)size); return -1; } /* * $ATTRIBUTE_LIST shouldn't be greater than 0x40000, otherwise * Windows would crash. This is not listed in the AttrDef. */ if (type == AT_ATTRIBUTE_LIST && size > 0x40000) { errno = ERANGE; ntfs_log_perror("Too large attrlist (%lld)", (long long)size); return -1; } ad = ntfs_attr_find_in_attrdef(vol, type); if (!ad) return -1; min_size = sle64_to_cpu(ad->min_size); max_size = sle64_to_cpu(ad->max_size); if ((min_size && (size < min_size)) || ((max_size > 0) && (size > max_size))) { errno = ERANGE; ntfs_log_perror("Attr type %d size check failed (min,size,max=" "%lld,%lld,%lld)", type, (long long)min_size, (long long)size, (long long)max_size); return -1; } return 0; } /** * ntfs_attr_can_be_non_resident - check if an attribute can be non-resident * @vol: ntfs volume to which the attribute belongs * @type: attribute type to check * @name: attribute name to check * @name_len: attribute name length * * Check whether the attribute of @type and @name with name length @name_len on * the ntfs volume @vol is allowed to be non-resident. This information is * obtained from $AttrDef system file and is augmented by rules imposed by * Microsoft (e.g. see http://support.microsoft.com/kb/974729/). * * Return 0 if the attribute is allowed to be non-resident and -1 if not or an * error occurred. On error the error code is stored in errno. The following * error codes are defined: * EPERM - The attribute is not allowed to be non-resident. * ENOENT - The attribute @type is not specified in $AttrDef. * EINVAL - Invalid parameters (e.g. @vol is not valid). */ static int ntfs_attr_can_be_non_resident(const ntfs_volume *vol, const ATTR_TYPES type, const ntfschar *name, int name_len) { ATTR_DEF *ad; BOOL allowed; /* * Microsoft has decreed that $LOGGED_UTILITY_STREAM attributes with a * name of $TXF_DATA must be resident despite the entry for * $LOGGED_UTILITY_STREAM in $AttrDef allowing them to be non-resident. * Failure to obey this on the root directory mft record of a volume * causes Windows Vista and later to see the volume as a RAW volume and * thus cannot mount it at all. */ if ((type == AT_LOGGED_UTILITY_STREAM) && name && ntfs_names_are_equal(TXF_DATA, 9, name, name_len, CASE_SENSITIVE, vol->upcase, vol->upcase_len)) allowed = FALSE; else { /* Find the attribute definition record in $AttrDef. */ ad = ntfs_attr_find_in_attrdef(vol, type); if (!ad) return -1; /* Check the flags and return the result. */ allowed = !(ad->flags & ATTR_DEF_RESIDENT); } if (!allowed) { errno = EPERM; ntfs_log_trace("Attribute can't be non-resident\n"); return -1; } return 0; } /** * ntfs_attr_can_be_resident - check if an attribute can be resident * @vol: ntfs volume to which the attribute belongs * @type: attribute type which to check * * Check whether the attribute of @type on the ntfs volume @vol is allowed to * be resident. This information is derived from our ntfs knowledge and may * not be completely accurate, especially when user defined attributes are * present. Basically we allow everything to be resident except for index * allocation and extended attribute attributes. * * Return 0 if the attribute is allowed to be resident and -1 if not or an * error occurred. On error the error code is stored in errno. The following * error codes are defined: * EPERM - The attribute is not allowed to be resident. * EINVAL - Invalid parameters (e.g. @vol is not valid). * * Warning: In the system file $MFT the attribute $Bitmap must be non-resident * otherwise windows will not boot (blue screen of death)! We cannot * check for this here as we don't know which inode's $Bitmap is being * asked about so the caller needs to special case this. */ int ntfs_attr_can_be_resident(const ntfs_volume *vol, const ATTR_TYPES type) { if (!vol || !vol->attrdef || !type) { errno = EINVAL; return -1; } if (type != AT_INDEX_ALLOCATION) return 0; ntfs_log_trace("Attribute can't be resident\n"); errno = EPERM; return -1; } /** * ntfs_make_room_for_attr - make room for an attribute inside an mft record * @m: mft record * @pos: position at which to make space * @size: byte size to make available at this position * * @pos points to the attribute in front of which we want to make space. * * Return 0 on success or -1 on error. On error the error code is stored in * errno. Possible error codes are: * ENOSPC - There is not enough space available to complete operation. The * caller has to make space before calling this. * EINVAL - Input parameters were faulty. */ int ntfs_make_room_for_attr(MFT_RECORD *m, u8 *pos, u32 size) { u32 biu; ntfs_log_trace("Entering for pos 0x%d, size %u.\n", (int)(pos - (u8*)m), (unsigned) size); /* Make size 8-byte alignment. */ size = (size + 7) & ~7; /* Rigorous consistency checks. */ if (!m || !pos || pos < (u8*)m) { errno = EINVAL; ntfs_log_perror("%s: pos=%p m=%p", __FUNCTION__, pos, m); return -1; } /* The -8 is for the attribute terminator. */ if (pos - (u8*)m > (int)le32_to_cpu(m->bytes_in_use) - 8) { errno = EINVAL; return -1; } /* Nothing to do. */ if (!size) return 0; biu = le32_to_cpu(m->bytes_in_use); /* Do we have enough space? */ if (biu + size > le32_to_cpu(m->bytes_allocated) || pos + size > (u8*)m + le32_to_cpu(m->bytes_allocated)) { errno = ENOSPC; ntfs_log_trace("No enough space in the MFT record\n"); return -1; } /* Move everything after pos to pos + size. */ memmove(pos + size, pos, biu - (pos - (u8*)m)); /* Update mft record. */ m->bytes_in_use = cpu_to_le32(biu + size); return 0; } /** * ntfs_resident_attr_record_add - add resident attribute to inode * @ni: opened ntfs inode to which MFT record add attribute * @type: type of the new attribute * @name: name of the new attribute * @name_len: name length of the new attribute * @val: value of the new attribute * @size: size of new attribute (length of @val, if @val != NULL) * @flags: flags of the new attribute * * Return offset to attribute from the beginning of the mft record on success * and -1 on error. On error the error code is stored in errno. * Possible error codes are: * EINVAL - Invalid arguments passed to function. * EEXIST - Attribute of such type and with same name already exists. * EIO - I/O error occurred or damaged filesystem. */ int ntfs_resident_attr_record_add(ntfs_inode *ni, ATTR_TYPES type, ntfschar *name, u8 name_len, u8 *val, u32 size, ATTR_FLAGS data_flags) { ntfs_attr_search_ctx *ctx; u32 length; ATTR_RECORD *a; MFT_RECORD *m; int err, offset; ntfs_inode *base_ni; ntfs_log_trace("Entering for inode 0x%llx, attr 0x%x, flags 0x%x.\n", (long long) ni->mft_no, (unsigned) type, (unsigned) data_flags); if (!ni || (!name && name_len)) { errno = EINVAL; return -1; } if (ntfs_attr_can_be_resident(ni->vol, type)) { if (errno == EPERM) ntfs_log_trace("Attribute can't be resident.\n"); else ntfs_log_trace("ntfs_attr_can_be_resident failed.\n"); return -1; } /* Locate place where record should be. */ ctx = ntfs_attr_get_search_ctx(ni, NULL); if (!ctx) return -1; /* * Use ntfs_attr_find instead of ntfs_attr_lookup to find place for * attribute in @ni->mrec, not any extent inode in case if @ni is base * file record. */ if (!ntfs_attr_find(type, name, name_len, CASE_SENSITIVE, val, size, ctx)) { err = EEXIST; ntfs_log_trace("Attribute already present.\n"); goto put_err_out; } if (errno != ENOENT) { err = EIO; goto put_err_out; } a = ctx->attr; m = ctx->mrec; /* Make room for attribute. */ length = offsetof(ATTR_RECORD, resident_end) + ((name_len * sizeof(ntfschar) + 7) & ~7) + ((size + 7) & ~7); if (ntfs_make_room_for_attr(ctx->mrec, (u8*) ctx->attr, length)) { err = errno; ntfs_log_trace("Failed to make room for attribute.\n"); goto put_err_out; } /* Setup record fields. */ offset = ((u8*)a - (u8*)m); a->type = type; a->length = cpu_to_le32(length); a->non_resident = 0; a->name_length = name_len; a->name_offset = (name_len ? cpu_to_le16(offsetof(ATTR_RECORD, resident_end)) : const_cpu_to_le16(0)); a->flags = data_flags; a->instance = m->next_attr_instance; a->value_length = cpu_to_le32(size); a->value_offset = cpu_to_le16(length - ((size + 7) & ~7)); if (val) memcpy((u8*)a + le16_to_cpu(a->value_offset), val, size); else memset((u8*)a + le16_to_cpu(a->value_offset), 0, size); if (type == AT_FILE_NAME) a->resident_flags = RESIDENT_ATTR_IS_INDEXED; else a->resident_flags = 0; if (name_len) memcpy((u8*)a + le16_to_cpu(a->name_offset), name, sizeof(ntfschar) * name_len); m->next_attr_instance = cpu_to_le16((le16_to_cpu(m->next_attr_instance) + 1) & 0xffff); if (ni->nr_extents == -1) base_ni = ni->base_ni; else base_ni = ni; if (type != AT_ATTRIBUTE_LIST && NInoAttrList(base_ni)) { if (ntfs_attrlist_entry_add(ni, a)) { err = errno; ntfs_attr_record_resize(m, a, 0); ntfs_log_trace("Failed add attribute entry to " "ATTRIBUTE_LIST.\n"); goto put_err_out; } } if (ni->mrec->flags & MFT_RECORD_IS_DIRECTORY ? type == AT_INDEX_ROOT && name == NTFS_INDEX_I30 : type == AT_DATA && name == AT_UNNAMED) { ni->data_size = size; ni->allocated_size = (size + 7) & ~7; set_nino_flag(ni,KnownSize); } ntfs_inode_mark_dirty(ni); ntfs_attr_put_search_ctx(ctx); return offset; put_err_out: ntfs_attr_put_search_ctx(ctx); errno = err; return -1; } /** * ntfs_non_resident_attr_record_add - add extent of non-resident attribute * @ni: opened ntfs inode to which MFT record add attribute * @type: type of the new attribute extent * @name: name of the new attribute extent * @name_len: name length of the new attribute extent * @lowest_vcn: lowest vcn of the new attribute extent * @dataruns_size: dataruns size of the new attribute extent * @flags: flags of the new attribute extent * * Return offset to attribute from the beginning of the mft record on success * and -1 on error. On error the error code is stored in errno. * Possible error codes are: * EINVAL - Invalid arguments passed to function. * EEXIST - Attribute of such type, with same lowest vcn and with same * name already exists. * EIO - I/O error occurred or damaged filesystem. */ int ntfs_non_resident_attr_record_add(ntfs_inode *ni, ATTR_TYPES type, ntfschar *name, u8 name_len, VCN lowest_vcn, int dataruns_size, ATTR_FLAGS flags) { ntfs_attr_search_ctx *ctx; u32 length; ATTR_RECORD *a; MFT_RECORD *m; ntfs_inode *base_ni; int err, offset; ntfs_log_trace("Entering for inode 0x%llx, attr 0x%x, lowest_vcn %lld, " "dataruns_size %d, flags 0x%x.\n", (long long) ni->mft_no, (unsigned) type, (long long) lowest_vcn, dataruns_size, (unsigned) flags); if (!ni || dataruns_size <= 0 || (!name && name_len)) { errno = EINVAL; return -1; } if (ntfs_attr_can_be_non_resident(ni->vol, type, name, name_len)) { if (errno == EPERM) ntfs_log_perror("Attribute can't be non resident"); else ntfs_log_perror("ntfs_attr_can_be_non_resident failed"); return -1; } /* Locate place where record should be. */ ctx = ntfs_attr_get_search_ctx(ni, NULL); if (!ctx) return -1; /* * Use ntfs_attr_find instead of ntfs_attr_lookup to find place for * attribute in @ni->mrec, not any extent inode in case if @ni is base * file record. */ if (!ntfs_attr_find(type, name, name_len, CASE_SENSITIVE, NULL, 0, ctx)) { err = EEXIST; ntfs_log_perror("Attribute 0x%x already present", type); goto put_err_out; } if (errno != ENOENT) { ntfs_log_perror("ntfs_attr_find failed"); err = EIO; goto put_err_out; } a = ctx->attr; m = ctx->mrec; /* Make room for attribute. */ dataruns_size = (dataruns_size + 7) & ~7; length = offsetof(ATTR_RECORD, compressed_size) + ((sizeof(ntfschar) * name_len + 7) & ~7) + dataruns_size + ((flags & (ATTR_IS_COMPRESSED | ATTR_IS_SPARSE)) ? sizeof(a->compressed_size) : 0); if (ntfs_make_room_for_attr(ctx->mrec, (u8*) ctx->attr, length)) { err = errno; ntfs_log_perror("Failed to make room for attribute"); goto put_err_out; } /* Setup record fields. */ a->type = type; a->length = cpu_to_le32(length); a->non_resident = 1; a->name_length = name_len; a->name_offset = cpu_to_le16(offsetof(ATTR_RECORD, compressed_size) + ((flags & (ATTR_IS_COMPRESSED | ATTR_IS_SPARSE)) ? sizeof(a->compressed_size) : 0)); a->flags = flags; a->instance = m->next_attr_instance; a->lowest_vcn = cpu_to_sle64(lowest_vcn); a->mapping_pairs_offset = cpu_to_le16(length - dataruns_size); a->compression_unit = (flags & ATTR_IS_COMPRESSED) ? STANDARD_COMPRESSION_UNIT : 0; /* If @lowest_vcn == 0, than setup empty attribute. */ if (!lowest_vcn) { a->highest_vcn = cpu_to_sle64(-1); a->allocated_size = 0; a->data_size = 0; a->initialized_size = 0; /* Set empty mapping pairs. */ *((u8*)a + le16_to_cpu(a->mapping_pairs_offset)) = 0; } if (name_len) memcpy((u8*)a + le16_to_cpu(a->name_offset), name, sizeof(ntfschar) * name_len); m->next_attr_instance = cpu_to_le16((le16_to_cpu(m->next_attr_instance) + 1) & 0xffff); if (ni->nr_extents == -1) base_ni = ni->base_ni; else base_ni = ni; if (type != AT_ATTRIBUTE_LIST && NInoAttrList(base_ni)) { if (ntfs_attrlist_entry_add(ni, a)) { err = errno; ntfs_log_perror("Failed add attr entry to attrlist"); ntfs_attr_record_resize(m, a, 0); goto put_err_out; } } ntfs_inode_mark_dirty(ni); /* * Locate offset from start of the MFT record where new attribute is * placed. We need relookup it, because record maybe moved during * update of attribute list. */ ntfs_attr_reinit_search_ctx(ctx); if (ntfs_attr_lookup(type, name, name_len, CASE_SENSITIVE, lowest_vcn, NULL, 0, ctx)) { ntfs_log_perror("%s: attribute lookup failed", __FUNCTION__); ntfs_attr_put_search_ctx(ctx); return -1; } offset = (u8*)ctx->attr - (u8*)ctx->mrec; ntfs_attr_put_search_ctx(ctx); return offset; put_err_out: ntfs_attr_put_search_ctx(ctx); errno = err; return -1; } /** * ntfs_attr_record_rm - remove attribute extent * @ctx: search context describing the attribute which should be removed * * If this function succeed, user should reinit search context if he/she wants * use it anymore. * * Return 0 on success and -1 on error. On error the error code is stored in * errno. Possible error codes are: * EINVAL - Invalid arguments passed to function. * EIO - I/O error occurred or damaged filesystem. */ int ntfs_attr_record_rm(ntfs_attr_search_ctx *ctx) { ntfs_inode *base_ni, *ni; ATTR_TYPES type; if (!ctx || !ctx->ntfs_ino || !ctx->mrec || !ctx->attr) { errno = EINVAL; return -1; } ntfs_log_trace("Entering for inode 0x%llx, attr 0x%x.\n", (long long) ctx->ntfs_ino->mft_no, (unsigned) le32_to_cpu(ctx->attr->type)); type = ctx->attr->type; ni = ctx->ntfs_ino; if (ctx->base_ntfs_ino) base_ni = ctx->base_ntfs_ino; else base_ni = ctx->ntfs_ino; /* Remove attribute itself. */ if (ntfs_attr_record_resize(ctx->mrec, ctx->attr, 0)) { ntfs_log_trace("Couldn't remove attribute record. Bug or damaged MFT " "record.\n"); if (NInoAttrList(base_ni) && type != AT_ATTRIBUTE_LIST) if (ntfs_attrlist_entry_add(ni, ctx->attr)) ntfs_log_trace("Rollback failed. Leaving inconstant " "metadata.\n"); errno = EIO; return -1; } ntfs_inode_mark_dirty(ni); /* * Remove record from $ATTRIBUTE_LIST if present and we don't want * delete $ATTRIBUTE_LIST itself. */ if (NInoAttrList(base_ni) && type != AT_ATTRIBUTE_LIST) { if (ntfs_attrlist_entry_rm(ctx)) { ntfs_log_trace("Couldn't delete record from " "$ATTRIBUTE_LIST.\n"); return -1; } } /* Post $ATTRIBUTE_LIST delete setup. */ if (type == AT_ATTRIBUTE_LIST) { if (NInoAttrList(base_ni) && base_ni->attr_list) free(base_ni->attr_list); base_ni->attr_list = NULL; NInoClearAttrList(base_ni); NInoAttrListClearDirty(base_ni); } /* Free MFT record, if it doesn't contain attributes. */ if (le32_to_cpu(ctx->mrec->bytes_in_use) - le16_to_cpu(ctx->mrec->attrs_offset) == 8) { if (ntfs_mft_record_free(ni->vol, ni)) { // FIXME: We need rollback here. ntfs_log_trace("Couldn't free MFT record.\n"); errno = EIO; return -1; } /* Remove done if we freed base inode. */ if (ni == base_ni) return 0; } if (type == AT_ATTRIBUTE_LIST || !NInoAttrList(base_ni)) return 0; /* Remove attribute list if we don't need it any more. */ if (!ntfs_attrlist_need(base_ni)) { ntfs_attr_reinit_search_ctx(ctx); if (ntfs_attr_lookup(AT_ATTRIBUTE_LIST, NULL, 0, CASE_SENSITIVE, 0, NULL, 0, ctx)) { /* * FIXME: Should we succeed here? Definitely something * goes wrong because NInoAttrList(base_ni) returned * that we have got attribute list. */ ntfs_log_trace("Couldn't find attribute list. Succeed " "anyway.\n"); return 0; } /* Deallocate clusters. */ if (ctx->attr->non_resident) { runlist *al_rl; al_rl = ntfs_mapping_pairs_decompress(base_ni->vol, ctx->attr, NULL); if (!al_rl) { ntfs_log_trace("Couldn't decompress attribute list " "runlist. Succeed anyway.\n"); return 0; } if (ntfs_cluster_free_from_rl(base_ni->vol, al_rl)) { ntfs_log_trace("Leaking clusters! Run chkdsk. " "Couldn't free clusters from " "attribute list runlist.\n"); } free(al_rl); } /* Remove attribute record itself. */ if (ntfs_attr_record_rm(ctx)) { /* * FIXME: Should we succeed here? BTW, chkdsk doesn't * complain if it find MFT record with attribute list, * but without extents. */ ntfs_log_trace("Couldn't remove attribute list. Succeed " "anyway.\n"); return 0; } } return 0; } /** * ntfs_attr_add - add attribute to inode * @ni: opened ntfs inode to which add attribute * @type: type of the new attribute * @name: name in unicode of the new attribute * @name_len: name length in unicode characters of the new attribute * @val: value of new attribute * @size: size of the new attribute / length of @val (if specified) * * @val should always be specified for always resident attributes (eg. FILE_NAME * attribute), for attributes that can become non-resident @val can be NULL * (eg. DATA attribute). @size can be specified even if @val is NULL, in this * case data size will be equal to @size and initialized size will be equal * to 0. * * If inode haven't got enough space to add attribute, add attribute to one of * it extents, if no extents present or no one of them have enough space, than * allocate new extent and add attribute to it. * * If on one of this steps attribute list is needed but not present, than it is * added transparently to caller. So, this function should not be called with * @type == AT_ATTRIBUTE_LIST, if you really need to add attribute list call * ntfs_inode_add_attrlist instead. * * On success return 0. On error return -1 with errno set to the error code. */ int ntfs_attr_add(ntfs_inode *ni, ATTR_TYPES type, ntfschar *name, u8 name_len, u8 *val, s64 size) { u32 attr_rec_size; int err, i, offset; BOOL is_resident; BOOL can_be_non_resident = FALSE; ntfs_inode *attr_ni; ntfs_attr *na; ATTR_FLAGS data_flags; if (!ni || size < 0 || type == AT_ATTRIBUTE_LIST) { errno = EINVAL; ntfs_log_perror("%s: ni=%p size=%lld", __FUNCTION__, ni, (long long)size); return -1; } ntfs_log_trace("Entering for inode %lld, attr %x, size %lld.\n", (long long)ni->mft_no, type, (long long)size); if (ni->nr_extents == -1) ni = ni->base_ni; /* Check the attribute type and the size. */ if (ntfs_attr_size_bounds_check(ni->vol, type, size)) { if (errno == ENOENT) errno = EIO; return -1; } /* Sanity checks for always resident attributes. */ if (ntfs_attr_can_be_non_resident(ni->vol, type, name, name_len)) { if (errno != EPERM) { err = errno; ntfs_log_perror("ntfs_attr_can_be_non_resident failed"); goto err_out; } /* @val is mandatory. */ if (!val) { errno = EINVAL; ntfs_log_perror("val is mandatory for always resident " "attributes"); return -1; } if (size > ni->vol->mft_record_size) { errno = ERANGE; ntfs_log_perror("Attribute is too big"); return -1; } } else can_be_non_resident = TRUE; /* * Determine resident or not will be new attribute. We add 8 to size in * non resident case for mapping pairs. */ if (!ntfs_attr_can_be_resident(ni->vol, type)) { is_resident = TRUE; } else { if (errno != EPERM) { err = errno; ntfs_log_perror("ntfs_attr_can_be_resident failed"); goto err_out; } is_resident = FALSE; } /* Calculate attribute record size. */ if (is_resident) attr_rec_size = offsetof(ATTR_RECORD, resident_end) + ((name_len * sizeof(ntfschar) + 7) & ~7) + ((size + 7) & ~7); else attr_rec_size = offsetof(ATTR_RECORD, non_resident_end) + ((name_len * sizeof(ntfschar) + 7) & ~7) + 8; /* * If we have enough free space for the new attribute in the base MFT * record, then add attribute to it. */ if (le32_to_cpu(ni->mrec->bytes_allocated) - le32_to_cpu(ni->mrec->bytes_in_use) >= attr_rec_size) { attr_ni = ni; goto add_attr_record; } /* Try to add to extent inodes. */ if (ntfs_inode_attach_all_extents(ni)) { err = errno; ntfs_log_perror("Failed to attach all extents to inode"); goto err_out; } for (i = 0; i < ni->nr_extents; i++) { attr_ni = ni->extent_nis[i]; if (le32_to_cpu(attr_ni->mrec->bytes_allocated) - le32_to_cpu(attr_ni->mrec->bytes_in_use) >= attr_rec_size) goto add_attr_record; } /* There is no extent that contain enough space for new attribute. */ if (!NInoAttrList(ni)) { /* Add attribute list not present, add it and retry. */ if (ntfs_inode_add_attrlist(ni)) { err = errno; ntfs_log_perror("Failed to add attribute list"); goto err_out; } return ntfs_attr_add(ni, type, name, name_len, val, size); } /* Allocate new extent. */ attr_ni = ntfs_mft_record_alloc(ni->vol, ni); if (!attr_ni) { err = errno; ntfs_log_perror("Failed to allocate extent record"); goto err_out; } add_attr_record: if ((ni->flags & FILE_ATTR_COMPRESSED) && (ni->vol->major_ver >= 3) && NVolCompression(ni->vol) && (ni->vol->cluster_size <= MAX_COMPRESSION_CLUSTER_SIZE) && ((type == AT_DATA) || ((type == AT_INDEX_ROOT) && (name == NTFS_INDEX_I30)))) data_flags = ATTR_IS_COMPRESSED; else data_flags = const_cpu_to_le16(0); if (is_resident) { /* Add resident attribute. */ offset = ntfs_resident_attr_record_add(attr_ni, type, name, name_len, val, size, data_flags); if (offset < 0) { if (errno == ENOSPC && can_be_non_resident) goto add_non_resident; err = errno; ntfs_log_perror("Failed to add resident attribute"); goto free_err_out; } return 0; } add_non_resident: /* Add non resident attribute. */ offset = ntfs_non_resident_attr_record_add(attr_ni, type, name, name_len, 0, 8, data_flags); if (offset < 0) { err = errno; ntfs_log_perror("Failed to add non resident attribute"); goto free_err_out; } /* If @size == 0, we are done. */ if (!size) return 0; /* Open new attribute and resize it. */ na = ntfs_attr_open(ni, type, name, name_len); if (!na) { err = errno; ntfs_log_perror("Failed to open just added attribute"); goto rm_attr_err_out; } /* Resize and set attribute value. */ if (ntfs_attr_truncate(na, size) || (val && (ntfs_attr_pwrite(na, 0, size, val) != size))) { err = errno; ntfs_log_perror("Failed to initialize just added attribute"); if (ntfs_attr_rm(na)) ntfs_log_perror("Failed to remove just added attribute"); ntfs_attr_close(na); goto err_out; } ntfs_attr_close(na); return 0; rm_attr_err_out: /* Remove just added attribute. */ if (ntfs_attr_record_resize(attr_ni->mrec, (ATTR_RECORD*)((u8*)attr_ni->mrec + offset), 0)) ntfs_log_perror("Failed to remove just added attribute #2"); free_err_out: /* Free MFT record, if it doesn't contain attributes. */ if (le32_to_cpu(attr_ni->mrec->bytes_in_use) - le16_to_cpu(attr_ni->mrec->attrs_offset) == 8) if (ntfs_mft_record_free(attr_ni->vol, attr_ni)) ntfs_log_perror("Failed to free MFT record"); err_out: errno = err; return -1; } /* * Change an attribute flag */ int ntfs_attr_set_flags(ntfs_inode *ni, ATTR_TYPES type, ntfschar *name, u8 name_len, ATTR_FLAGS flags, ATTR_FLAGS mask) { ntfs_attr_search_ctx *ctx; int res; res = -1; /* Search for designated attribute */ ctx = ntfs_attr_get_search_ctx(ni, NULL); if (ctx) { if (!ntfs_attr_lookup(type, name, name_len, CASE_SENSITIVE, 0, NULL, 0, ctx)) { /* do the requested change (all small endian le16) */ ctx->attr->flags = (ctx->attr->flags & ~mask) | (flags & mask); NInoSetDirty(ni); res = 0; } ntfs_attr_put_search_ctx(ctx); } return (res); } /** * ntfs_attr_rm - remove attribute from ntfs inode * @na: opened ntfs attribute to delete * * Remove attribute and all it's extents from ntfs inode. If attribute was non * resident also free all clusters allocated by attribute. * * Return 0 on success or -1 on error with errno set to the error code. */ int ntfs_attr_rm(ntfs_attr *na) { ntfs_attr_search_ctx *ctx; int ret = 0; if (!na) { ntfs_log_trace("Invalid arguments passed.\n"); errno = EINVAL; return -1; } ntfs_log_trace("Entering for inode 0x%llx, attr 0x%x.\n", (long long) na->ni->mft_no, na->type); /* Free cluster allocation. */ if (NAttrNonResident(na)) { if (ntfs_attr_map_whole_runlist(na)) return -1; if (ntfs_cluster_free(na->ni->vol, na, 0, -1) < 0) { ntfs_log_trace("Failed to free cluster allocation. Leaving " "inconstant metadata.\n"); ret = -1; } } /* Search for attribute extents and remove them all. */ ctx = ntfs_attr_get_search_ctx(na->ni, NULL); if (!ctx) return -1; while (!ntfs_attr_lookup(na->type, na->name, na->name_len, CASE_SENSITIVE, 0, NULL, 0, ctx)) { if (ntfs_attr_record_rm(ctx)) { ntfs_log_trace("Failed to remove attribute extent. Leaving " "inconstant metadata.\n"); ret = -1; } ntfs_attr_reinit_search_ctx(ctx); } ntfs_attr_put_search_ctx(ctx); if (errno != ENOENT) { ntfs_log_trace("Attribute lookup failed. Probably leaving inconstant " "metadata.\n"); ret = -1; } return ret; } /** * ntfs_attr_record_resize - resize an attribute record * @m: mft record containing attribute record * @a: attribute record to resize * @new_size: new size in bytes to which to resize the attribute record @a * * Resize the attribute record @a, i.e. the resident part of the attribute, in * the mft record @m to @new_size bytes. * * Return 0 on success and -1 on error with errno set to the error code. * The following error codes are defined: * ENOSPC - Not enough space in the mft record @m to perform the resize. * Note that on error no modifications have been performed whatsoever. * * Warning: If you make a record smaller without having copied all the data you * are interested in the data may be overwritten! */ int ntfs_attr_record_resize(MFT_RECORD *m, ATTR_RECORD *a, u32 new_size) { u32 old_size, alloc_size, attr_size; old_size = le32_to_cpu(m->bytes_in_use); alloc_size = le32_to_cpu(m->bytes_allocated); attr_size = le32_to_cpu(a->length); ntfs_log_trace("Sizes: old=%u alloc=%u attr=%u new=%u\n", (unsigned)old_size, (unsigned)alloc_size, (unsigned)attr_size, (unsigned)new_size); /* Align to 8 bytes, just in case the caller hasn't. */ new_size = (new_size + 7) & ~7; /* If the actual attribute length has changed, move things around. */ if (new_size != attr_size) { u32 new_muse = old_size - attr_size + new_size; /* Not enough space in this mft record. */ if (new_muse > alloc_size) { errno = ENOSPC; ntfs_log_trace("Not enough space in the MFT record " "(%u > %u)\n", new_muse, alloc_size); return -1; } if (a->type == AT_INDEX_ROOT && new_size > attr_size && new_muse + 120 > alloc_size && old_size + 120 <= alloc_size) { errno = ENOSPC; ntfs_log_trace("Too big INDEX_ROOT (%u > %u)\n", new_muse, alloc_size); return STATUS_RESIDENT_ATTRIBUTE_FILLED_MFT; } /* Move attributes following @a to their new location. */ memmove((u8 *)a + new_size, (u8 *)a + attr_size, old_size - ((u8 *)a - (u8 *)m) - attr_size); /* Adjust @m to reflect the change in used space. */ m->bytes_in_use = cpu_to_le32(new_muse); /* Adjust @a to reflect the new size. */ if (new_size >= offsetof(ATTR_REC, length) + sizeof(a->length)) a->length = cpu_to_le32(new_size); } return 0; } /** * ntfs_resident_attr_value_resize - resize the value of a resident attribute * @m: mft record containing attribute record * @a: attribute record whose value to resize * @new_size: new size in bytes to which to resize the attribute value of @a * * Resize the value of the attribute @a in the mft record @m to @new_size bytes. * If the value is made bigger, the newly "allocated" space is cleared. * * Return 0 on success and -1 on error with errno set to the error code. * The following error codes are defined: * ENOSPC - Not enough space in the mft record @m to perform the resize. * Note that on error no modifications have been performed whatsoever. */ int ntfs_resident_attr_value_resize(MFT_RECORD *m, ATTR_RECORD *a, const u32 new_size) { int ret; ntfs_log_trace("Entering for new size %u.\n", (unsigned)new_size); /* Resize the resident part of the attribute record. */ if ((ret = ntfs_attr_record_resize(m, a, (le16_to_cpu(a->value_offset) + new_size + 7) & ~7)) < 0) return ret; /* * If we made the attribute value bigger, clear the area between the * old size and @new_size. */ if (new_size > le32_to_cpu(a->value_length)) memset((u8*)a + le16_to_cpu(a->value_offset) + le32_to_cpu(a->value_length), 0, new_size - le32_to_cpu(a->value_length)); /* Finally update the length of the attribute value. */ a->value_length = cpu_to_le32(new_size); return 0; } /** * ntfs_attr_record_move_to - move attribute record to target inode * @ctx: attribute search context describing the attribute record * @ni: opened ntfs inode to which move attribute record * * If this function succeed, user should reinit search context if he/she wants * use it anymore. * * Return 0 on success and -1 on error with errno set to the error code. */ int ntfs_attr_record_move_to(ntfs_attr_search_ctx *ctx, ntfs_inode *ni) { ntfs_attr_search_ctx *nctx; ATTR_RECORD *a; int err; if (!ctx || !ctx->attr || !ctx->ntfs_ino || !ni) { ntfs_log_trace("Invalid arguments passed.\n"); errno = EINVAL; return -1; } ntfs_log_trace("Entering for ctx->attr->type 0x%x, ctx->ntfs_ino->mft_no " "0x%llx, ni->mft_no 0x%llx.\n", (unsigned) le32_to_cpu(ctx->attr->type), (long long) ctx->ntfs_ino->mft_no, (long long) ni->mft_no); if (ctx->ntfs_ino == ni) return 0; if (!ctx->al_entry) { ntfs_log_trace("Inode should contain attribute list to use this " "function.\n"); errno = EINVAL; return -1; } /* Find place in MFT record where attribute will be moved. */ a = ctx->attr; nctx = ntfs_attr_get_search_ctx(ni, NULL); if (!nctx) return -1; /* * Use ntfs_attr_find instead of ntfs_attr_lookup to find place for * attribute in @ni->mrec, not any extent inode in case if @ni is base * file record. */ if (!ntfs_attr_find(a->type, (ntfschar*)((u8*)a + le16_to_cpu( a->name_offset)), a->name_length, CASE_SENSITIVE, NULL, 0, nctx)) { ntfs_log_trace("Attribute of such type, with same name already " "present in this MFT record.\n"); err = EEXIST; goto put_err_out; } if (errno != ENOENT) { err = errno; ntfs_log_debug("Attribute lookup failed.\n"); goto put_err_out; } /* Make space and move attribute. */ if (ntfs_make_room_for_attr(ni->mrec, (u8*) nctx->attr, le32_to_cpu(a->length))) { err = errno; ntfs_log_trace("Couldn't make space for attribute.\n"); goto put_err_out; } memcpy(nctx->attr, a, le32_to_cpu(a->length)); nctx->attr->instance = nctx->mrec->next_attr_instance; nctx->mrec->next_attr_instance = cpu_to_le16( (le16_to_cpu(nctx->mrec->next_attr_instance) + 1) & 0xffff); ntfs_attr_record_resize(ctx->mrec, a, 0); ntfs_inode_mark_dirty(ctx->ntfs_ino); ntfs_inode_mark_dirty(ni); /* Update attribute list. */ ctx->al_entry->mft_reference = MK_LE_MREF(ni->mft_no, le16_to_cpu(ni->mrec->sequence_number)); ctx->al_entry->instance = nctx->attr->instance; ntfs_attrlist_mark_dirty(ni); ntfs_attr_put_search_ctx(nctx); return 0; put_err_out: ntfs_attr_put_search_ctx(nctx); errno = err; return -1; } /** * ntfs_attr_record_move_away - move away attribute record from it's mft record * @ctx: attribute search context describing the attribute record * @extra: minimum amount of free space in the new holder of record * * New attribute record holder must have free @extra bytes after moving * attribute record to it. * * If this function succeed, user should reinit search context if he/she wants * use it anymore. * * Return 0 on success and -1 on error with errno set to the error code. */ int ntfs_attr_record_move_away(ntfs_attr_search_ctx *ctx, int extra) { ntfs_inode *base_ni, *ni; MFT_RECORD *m; int i; if (!ctx || !ctx->attr || !ctx->ntfs_ino || extra < 0) { errno = EINVAL; ntfs_log_perror("%s: ctx=%p ctx->attr=%p extra=%d", __FUNCTION__, ctx, ctx ? ctx->attr : NULL, extra); return -1; } ntfs_log_trace("Entering for attr 0x%x, inode %llu\n", (unsigned) le32_to_cpu(ctx->attr->type), (unsigned long long)ctx->ntfs_ino->mft_no); if (ctx->ntfs_ino->nr_extents == -1) base_ni = ctx->base_ntfs_ino; else base_ni = ctx->ntfs_ino; if (!NInoAttrList(base_ni)) { errno = EINVAL; ntfs_log_perror("Inode %llu has no attrlist", (unsigned long long)base_ni->mft_no); return -1; } if (ntfs_inode_attach_all_extents(ctx->ntfs_ino)) { ntfs_log_perror("Couldn't attach extents, inode=%llu", (unsigned long long)base_ni->mft_no); return -1; } /* Walk through all extents and try to move attribute to them. */ for (i = 0; i < base_ni->nr_extents; i++) { ni = base_ni->extent_nis[i]; m = ni->mrec; if (ctx->ntfs_ino->mft_no == ni->mft_no) continue; if (le32_to_cpu(m->bytes_allocated) - le32_to_cpu(m->bytes_in_use) < le32_to_cpu(ctx->attr->length) + extra) continue; /* * ntfs_attr_record_move_to can fail if extent with other lowest * VCN already present in inode we trying move record to. So, * do not return error. */ if (!ntfs_attr_record_move_to(ctx, ni)) return 0; } /* * Failed to move attribute to one of the current extents, so allocate * new extent and move attribute to it. */ ni = ntfs_mft_record_alloc(base_ni->vol, base_ni); if (!ni) { ntfs_log_perror("Couldn't allocate MFT record"); return -1; } if (ntfs_attr_record_move_to(ctx, ni)) { ntfs_log_perror("Couldn't move attribute to MFT record"); return -1; } return 0; } /** * ntfs_attr_make_non_resident - convert a resident to a non-resident attribute * @na: open ntfs attribute to make non-resident * @ctx: ntfs search context describing the attribute * * Convert a resident ntfs attribute to a non-resident one. * * Return 0 on success and -1 on error with errno set to the error code. The * following error codes are defined: * EPERM - The attribute is not allowed to be non-resident. * TODO: others... * * NOTE to self: No changes in the attribute list are required to move from * a resident to a non-resident attribute. * * Warning: We do not set the inode dirty and we do not write out anything! * We expect the caller to do this as this is a fairly low level * function and it is likely there will be further changes made. */ int ntfs_attr_make_non_resident(ntfs_attr *na, ntfs_attr_search_ctx *ctx) { s64 new_allocated_size, bw; ntfs_volume *vol = na->ni->vol; ATTR_REC *a = ctx->attr; runlist *rl; int mp_size, mp_ofs, name_ofs, arec_size, err; ntfs_log_trace("Entering for inode 0x%llx, attr 0x%x.\n", (unsigned long long)na->ni->mft_no, na->type); /* Some preliminary sanity checking. */ if (NAttrNonResident(na)) { ntfs_log_trace("Eeek! Trying to make non-resident attribute " "non-resident. Aborting...\n"); errno = EINVAL; return -1; } /* Check that the attribute is allowed to be non-resident. */ if (ntfs_attr_can_be_non_resident(vol, na->type, na->name, na->name_len)) return -1; new_allocated_size = (le32_to_cpu(a->value_length) + vol->cluster_size - 1) & ~(vol->cluster_size - 1); if (new_allocated_size > 0) { if ((a->flags & ATTR_COMPRESSION_MASK) == ATTR_IS_COMPRESSED) { /* must allocate full compression blocks */ new_allocated_size = ((new_allocated_size - 1) | ((1L << (STANDARD_COMPRESSION_UNIT + vol->cluster_size_bits)) - 1)) + 1; } /* Start by allocating clusters to hold the attribute value. */ rl = ntfs_cluster_alloc(vol, 0, new_allocated_size >> vol->cluster_size_bits, -1, DATA_ZONE); if (!rl) return -1; } else rl = NULL; /* * Setup the in-memory attribute structure to be non-resident so that * we can use ntfs_attr_pwrite(). */ NAttrSetNonResident(na); NAttrSetBeingNonResident(na); na->rl = rl; na->allocated_size = new_allocated_size; na->data_size = na->initialized_size = le32_to_cpu(a->value_length); /* * FIXME: For now just clear all of these as we don't support them when * writing. */ NAttrClearSparse(na); NAttrClearEncrypted(na); if ((a->flags & ATTR_COMPRESSION_MASK) == ATTR_IS_COMPRESSED) { /* set compression writing parameters */ na->compression_block_size = 1 << (STANDARD_COMPRESSION_UNIT + vol->cluster_size_bits); na->compression_block_clusters = 1 << STANDARD_COMPRESSION_UNIT; } if (rl) { /* Now copy the attribute value to the allocated cluster(s). */ bw = ntfs_attr_pwrite(na, 0, le32_to_cpu(a->value_length), (u8*)a + le16_to_cpu(a->value_offset)); if (bw != le32_to_cpu(a->value_length)) { err = errno; ntfs_log_debug("Eeek! Failed to write out attribute value " "(bw = %lli, errno = %i). " "Aborting...\n", (long long)bw, err); if (bw >= 0) err = EIO; goto cluster_free_err_out; } } /* Determine the size of the mapping pairs array. */ mp_size = ntfs_get_size_for_mapping_pairs(vol, rl, 0, INT_MAX); if (mp_size < 0) { err = errno; ntfs_log_debug("Eeek! Failed to get size for mapping pairs array. " "Aborting...\n"); goto cluster_free_err_out; } /* Calculate new offsets for the name and the mapping pairs array. */ if (na->ni->flags & FILE_ATTR_COMPRESSED) name_ofs = (sizeof(ATTR_REC) + 7) & ~7; else name_ofs = (sizeof(ATTR_REC) - sizeof(a->compressed_size) + 7) & ~7; mp_ofs = (name_ofs + a->name_length * sizeof(ntfschar) + 7) & ~7; /* * Determine the size of the resident part of the non-resident * attribute record. (Not compressed thus no compressed_size element * present.) */ arec_size = (mp_ofs + mp_size + 7) & ~7; /* Resize the resident part of the attribute record. */ if (ntfs_attr_record_resize(ctx->mrec, a, arec_size) < 0) { err = errno; goto cluster_free_err_out; } /* * Convert the resident part of the attribute record to describe a * non-resident attribute. */ a->non_resident = 1; /* Move the attribute name if it exists and update the offset. */ if (a->name_length) memmove((u8*)a + name_ofs, (u8*)a + le16_to_cpu(a->name_offset), a->name_length * sizeof(ntfschar)); a->name_offset = cpu_to_le16(name_ofs); /* Setup the fields specific to non-resident attributes. */ a->lowest_vcn = cpu_to_sle64(0); a->highest_vcn = cpu_to_sle64((new_allocated_size - 1) >> vol->cluster_size_bits); a->mapping_pairs_offset = cpu_to_le16(mp_ofs); /* * Update the flags to match the in-memory ones. * However cannot change the compression state if we had * a fuse_file_info open with a mark for release. * The decisions about compression can only be made when * creating/recreating the stream, not when making non resident. */ a->flags &= ~(ATTR_IS_SPARSE | ATTR_IS_ENCRYPTED); if ((a->flags & ATTR_COMPRESSION_MASK) == ATTR_IS_COMPRESSED) { /* support only ATTR_IS_COMPRESSED compression mode */ a->compression_unit = STANDARD_COMPRESSION_UNIT; a->compressed_size = const_cpu_to_le64(0); } else { a->compression_unit = 0; a->flags &= ~ATTR_COMPRESSION_MASK; na->data_flags = a->flags; } memset(&a->reserved1, 0, sizeof(a->reserved1)); a->allocated_size = cpu_to_sle64(new_allocated_size); a->data_size = a->initialized_size = cpu_to_sle64(na->data_size); /* Generate the mapping pairs array in the attribute record. */ if (ntfs_mapping_pairs_build(vol, (u8*)a + mp_ofs, arec_size - mp_ofs, rl, 0, NULL) < 0) { // FIXME: Eeek! We need rollback! (AIA) ntfs_log_trace("Eeek! Failed to build mapping pairs. Leaving " "corrupt attribute record on disk. In memory " "runlist is still intact! Error code is %i. " "FIXME: Need to rollback instead!\n", errno); return -1; } /* Done! */ return 0; cluster_free_err_out: if (rl && ntfs_cluster_free(vol, na, 0, -1) < 0) ntfs_log_trace("Eeek! Failed to release allocated clusters in error " "code path. Leaving inconsistent metadata...\n"); NAttrClearNonResident(na); na->allocated_size = na->data_size; na->rl = NULL; free(rl); errno = err; return -1; } static int ntfs_resident_attr_resize(ntfs_attr *na, const s64 newsize); /** * ntfs_resident_attr_resize - resize a resident, open ntfs attribute * @na: resident ntfs attribute to resize * @newsize: new size (in bytes) to which to resize the attribute * * Change the size of a resident, open ntfs attribute @na to @newsize bytes. * Can also be used to force an attribute non-resident. In this case, the * size cannot be changed. * * On success return 0 * On error return values are: * STATUS_RESIDENT_ATTRIBUTE_FILLED_MFT * STATUS_ERROR - otherwise * The following error codes are defined: * ENOMEM - Not enough memory to complete operation. * ERANGE - @newsize is not valid for the attribute type of @na. * ENOSPC - There is no enough space in base mft to resize $ATTRIBUTE_LIST. */ static int ntfs_resident_attr_resize_i(ntfs_attr *na, const s64 newsize, BOOL force_non_resident) { ntfs_attr_search_ctx *ctx; ntfs_volume *vol; ntfs_inode *ni; int err, ret = STATUS_ERROR; ntfs_log_trace("Inode 0x%llx attr 0x%x new size %lld\n", (unsigned long long)na->ni->mft_no, na->type, (long long)newsize); /* Get the attribute record that needs modification. */ ctx = ntfs_attr_get_search_ctx(na->ni, NULL); if (!ctx) return -1; if (ntfs_attr_lookup(na->type, na->name, na->name_len, 0, 0, NULL, 0, ctx)) { err = errno; ntfs_log_perror("ntfs_attr_lookup failed"); goto put_err_out; } vol = na->ni->vol; /* * Check the attribute type and the corresponding minimum and maximum * sizes against @newsize and fail if @newsize is out of bounds. */ if (ntfs_attr_size_bounds_check(vol, na->type, newsize) < 0) { err = errno; if (err == ENOENT) err = EIO; ntfs_log_perror("%s: bounds check failed", __FUNCTION__); goto put_err_out; } /* * If @newsize is bigger than the mft record we need to make the * attribute non-resident if the attribute type supports it. If it is * smaller we can go ahead and attempt the resize. */ if ((newsize < vol->mft_record_size) && !force_non_resident) { /* Perform the resize of the attribute record. */ if (!(ret = ntfs_resident_attr_value_resize(ctx->mrec, ctx->attr, newsize))) { /* Update attribute size everywhere. */ na->data_size = na->initialized_size = newsize; na->allocated_size = (newsize + 7) & ~7; if ((na->data_flags & ATTR_COMPRESSION_MASK) || NAttrSparse(na)) na->compressed_size = na->allocated_size; if (na->ni->mrec->flags & MFT_RECORD_IS_DIRECTORY ? na->type == AT_INDEX_ROOT && na->name == NTFS_INDEX_I30 : na->type == AT_DATA && na->name == AT_UNNAMED) { na->ni->data_size = na->data_size; if (((na->data_flags & ATTR_COMPRESSION_MASK) || NAttrSparse(na)) && NAttrNonResident(na)) na->ni->allocated_size = na->compressed_size; else na->ni->allocated_size = na->allocated_size; set_nino_flag(na->ni,KnownSize); if (na->type == AT_DATA) NInoFileNameSetDirty(na->ni); } goto resize_done; } /* Prefer AT_INDEX_ALLOCATION instead of AT_ATTRIBUTE_LIST */ if (ret == STATUS_RESIDENT_ATTRIBUTE_FILLED_MFT) { err = errno; goto put_err_out; } } /* There is not enough space in the mft record to perform the resize. */ /* Make the attribute non-resident if possible. */ if (!ntfs_attr_make_non_resident(na, ctx)) { ntfs_inode_mark_dirty(ctx->ntfs_ino); ntfs_attr_put_search_ctx(ctx); /* * do not truncate when forcing non-resident, this * could cause the attribute to be made resident again, * so size changes are not allowed. */ if (force_non_resident) { ret = 0; if (newsize != na->data_size) { ntfs_log_error("Cannot change size when" " forcing non-resident\n"); errno = EIO; ret = STATUS_ERROR; } return (ret); } /* Resize non-resident attribute */ return ntfs_attr_truncate(na, newsize); } else if (errno != ENOSPC && errno != EPERM) { err = errno; ntfs_log_perror("Failed to make attribute non-resident"); goto put_err_out; } /* Try to make other attributes non-resident and retry each time. */ ntfs_attr_init_search_ctx(ctx, NULL, na->ni->mrec); while (!ntfs_attr_lookup(AT_UNUSED, NULL, 0, 0, 0, NULL, 0, ctx)) { ntfs_attr *tna; ATTR_RECORD *a; a = ctx->attr; if (a->non_resident) continue; /* * Check out whether convert is reasonable. Assume that mapping * pairs will take 8 bytes. */ if (le32_to_cpu(a->length) <= offsetof(ATTR_RECORD, compressed_size) + ((a->name_length * sizeof(ntfschar) + 7) & ~7) + 8) continue; tna = ntfs_attr_open(na->ni, a->type, (ntfschar*)((u8*)a + le16_to_cpu(a->name_offset)), a->name_length); if (!tna) { err = errno; ntfs_log_perror("Couldn't open attribute"); goto put_err_out; } if (ntfs_attr_make_non_resident(tna, ctx)) { ntfs_attr_close(tna); continue; } if (((tna->data_flags & ATTR_COMPRESSION_MASK) == ATTR_IS_COMPRESSED) && ntfs_attr_pclose(tna)) { err = errno; ntfs_attr_close(tna); goto put_err_out; } ntfs_inode_mark_dirty(tna->ni); ntfs_attr_close(tna); ntfs_attr_put_search_ctx(ctx); return ntfs_resident_attr_resize_i(na, newsize, force_non_resident); } /* Check whether error occurred. */ if (errno != ENOENT) { err = errno; ntfs_log_perror("%s: Attribute lookup failed 1", __FUNCTION__); goto put_err_out; } /* * The standard information and attribute list attributes can't be * moved out from the base MFT record, so try to move out others. */ if (na->type==AT_STANDARD_INFORMATION || na->type==AT_ATTRIBUTE_LIST) { ntfs_attr_put_search_ctx(ctx); if (ntfs_inode_free_space(na->ni, offsetof(ATTR_RECORD, non_resident_end) + 8)) { ntfs_log_perror("Could not free space in MFT record"); return -1; } return ntfs_resident_attr_resize_i(na, newsize, force_non_resident); } /* * Move the attribute to a new mft record, creating an attribute list * attribute or modifying it if it is already present. */ /* Point search context back to attribute which we need resize. */ ntfs_attr_init_search_ctx(ctx, na->ni, NULL); if (ntfs_attr_lookup(na->type, na->name, na->name_len, CASE_SENSITIVE, 0, NULL, 0, ctx)) { ntfs_log_perror("%s: Attribute lookup failed 2", __FUNCTION__); err = errno; goto put_err_out; } /* * Check whether attribute is already single in this MFT record. * 8 added for the attribute terminator. */ if (le32_to_cpu(ctx->mrec->bytes_in_use) == le16_to_cpu(ctx->mrec->attrs_offset) + le32_to_cpu(ctx->attr->length) + 8) { err = ENOSPC; ntfs_log_trace("MFT record is filled with one attribute\n"); ret = STATUS_RESIDENT_ATTRIBUTE_FILLED_MFT; goto put_err_out; } /* Add attribute list if not present. */ if (na->ni->nr_extents == -1) ni = na->ni->base_ni; else ni = na->ni; if (!NInoAttrList(ni)) { ntfs_attr_put_search_ctx(ctx); if (ntfs_inode_add_attrlist(ni)) return -1; return ntfs_resident_attr_resize_i(na, newsize, force_non_resident); } /* Allocate new mft record. */ ni = ntfs_mft_record_alloc(vol, ni); if (!ni) { err = errno; ntfs_log_perror("Couldn't allocate new MFT record"); goto put_err_out; } /* Move attribute to it. */ if (ntfs_attr_record_move_to(ctx, ni)) { err = errno; ntfs_log_perror("Couldn't move attribute to new MFT record"); goto put_err_out; } /* Update ntfs attribute. */ if (na->ni->nr_extents == -1) na->ni = ni; ntfs_attr_put_search_ctx(ctx); /* Try to perform resize once again. */ return ntfs_resident_attr_resize_i(na, newsize, force_non_resident); resize_done: /* * Set the inode (and its base inode if it exists) dirty so it is * written out later. */ ntfs_inode_mark_dirty(ctx->ntfs_ino); ntfs_attr_put_search_ctx(ctx); return 0; put_err_out: ntfs_attr_put_search_ctx(ctx); errno = err; return ret; } static int ntfs_resident_attr_resize(ntfs_attr *na, const s64 newsize) { int ret; ntfs_log_enter("Entering\n"); ret = ntfs_resident_attr_resize_i(na, newsize, FALSE); ntfs_log_leave("\n"); return ret; } /* * Force an attribute to be made non-resident without * changing its size. * * This is particularly needed when the attribute has no data, * as the non-resident variant requires more space in the MFT * record, and may imply expelling some other attribute. * * As a consequence the existing ntfs_attr_search_ctx's have to * be closed or reinitialized. * * returns 0 if successful, * < 0 if failed, with errno telling why */ int ntfs_attr_force_non_resident(ntfs_attr *na) { int res; res = ntfs_resident_attr_resize_i(na, na->data_size, TRUE); if (!res && !NAttrNonResident(na)) { res = -1; errno = EIO; ntfs_log_error("Failed to force non-resident\n"); } return (res); } /** * ntfs_attr_make_resident - convert a non-resident to a resident attribute * @na: open ntfs attribute to make resident * @ctx: ntfs search context describing the attribute * * Convert a non-resident ntfs attribute to a resident one. * * Return 0 on success and -1 on error with errno set to the error code. The * following error codes are defined: * EINVAL - Invalid arguments passed. * EPERM - The attribute is not allowed to be resident. * EIO - I/O error, damaged inode or bug. * ENOSPC - There is no enough space to perform conversion. * EOPNOTSUPP - Requested conversion is not supported yet. * * Warning: We do not set the inode dirty and we do not write out anything! * We expect the caller to do this as this is a fairly low level * function and it is likely there will be further changes made. */ static int ntfs_attr_make_resident(ntfs_attr *na, ntfs_attr_search_ctx *ctx) { ntfs_volume *vol = na->ni->vol; ATTR_REC *a = ctx->attr; int name_ofs, val_ofs, err = EIO; s64 arec_size, bytes_read; ntfs_log_trace("Entering for inode 0x%llx, attr 0x%x.\n", (unsigned long long)na->ni->mft_no, na->type); /* Should be called for the first extent of the attribute. */ if (sle64_to_cpu(a->lowest_vcn)) { ntfs_log_trace("Eeek! Should be called for the first extent of the " "attribute. Aborting...\n"); errno = EINVAL; return -1; } /* Some preliminary sanity checking. */ if (!NAttrNonResident(na)) { ntfs_log_trace("Eeek! Trying to make resident attribute resident. " "Aborting...\n"); errno = EINVAL; return -1; } /* Make sure this is not $MFT/$BITMAP or Windows will not boot! */ if (na->type == AT_BITMAP && na->ni->mft_no == FILE_MFT) { errno = EPERM; return -1; } /* Check that the attribute is allowed to be resident. */ if (ntfs_attr_can_be_resident(vol, na->type)) return -1; if (na->data_flags & ATTR_IS_ENCRYPTED) { ntfs_log_trace("Making encrypted streams resident is not " "implemented yet.\n"); errno = EOPNOTSUPP; return -1; } /* Work out offsets into and size of the resident attribute. */ name_ofs = 24; /* = sizeof(resident_ATTR_REC); */ val_ofs = (name_ofs + a->name_length * sizeof(ntfschar) + 7) & ~7; arec_size = (val_ofs + na->data_size + 7) & ~7; /* Sanity check the size before we start modifying the attribute. */ if (le32_to_cpu(ctx->mrec->bytes_in_use) - le32_to_cpu(a->length) + arec_size > le32_to_cpu(ctx->mrec->bytes_allocated)) { errno = ENOSPC; ntfs_log_trace("Not enough space to make attribute resident\n"); return -1; } /* Read and cache the whole runlist if not already done. */ if (ntfs_attr_map_whole_runlist(na)) return -1; /* Move the attribute name if it exists and update the offset. */ if (a->name_length) { memmove((u8*)a + name_ofs, (u8*)a + le16_to_cpu(a->name_offset), a->name_length * sizeof(ntfschar)); } a->name_offset = cpu_to_le16(name_ofs); /* Resize the resident part of the attribute record. */ if (ntfs_attr_record_resize(ctx->mrec, a, arec_size) < 0) { /* * Bug, because ntfs_attr_record_resize should not fail (we * already checked that attribute fits MFT record). */ ntfs_log_error("BUG! Failed to resize attribute record. " "Please report to the %s. Aborting...\n", NTFS_DEV_LIST); errno = EIO; return -1; } /* Convert the attribute record to describe a resident attribute. */ a->non_resident = 0; a->flags = 0; a->value_length = cpu_to_le32(na->data_size); a->value_offset = cpu_to_le16(val_ofs); /* * If a data stream was wiped out, adjust the compression mode * to current state of compression flag */ if (!na->data_size && (na->type == AT_DATA) && (na->ni->vol->major_ver >= 3) && NVolCompression(na->ni->vol) && (na->ni->vol->cluster_size <= MAX_COMPRESSION_CLUSTER_SIZE) && (na->ni->flags & FILE_ATTR_COMPRESSED)) { a->flags |= ATTR_IS_COMPRESSED; na->data_flags = a->flags; } /* * File names cannot be non-resident so we would never see this here * but at least it serves as a reminder that there may be attributes * for which we do need to set this flag. (AIA) */ if (a->type == AT_FILE_NAME) a->resident_flags = RESIDENT_ATTR_IS_INDEXED; else a->resident_flags = 0; a->reservedR = 0; /* Sanity fixup... Shouldn't really happen. (AIA) */ if (na->initialized_size > na->data_size) na->initialized_size = na->data_size; /* Copy data from run list to resident attribute value. */ bytes_read = ntfs_rl_pread(vol, na->rl, 0, na->initialized_size, (u8*)a + val_ofs); if (bytes_read != na->initialized_size) { if (bytes_read < 0) err = errno; ntfs_log_trace("Eeek! Failed to read attribute data. Leaving " "inconstant metadata. Run chkdsk. " "Aborting...\n"); errno = err; return -1; } /* Clear memory in gap between initialized_size and data_size. */ if (na->initialized_size < na->data_size) memset((u8*)a + val_ofs + na->initialized_size, 0, na->data_size - na->initialized_size); /* * Deallocate clusters from the runlist. * * NOTE: We can use ntfs_cluster_free() because we have already mapped * the whole run list and thus it doesn't matter that the attribute * record is in a transiently corrupted state at this moment in time. */ if (ntfs_cluster_free(vol, na, 0, -1) < 0) { err = errno; ntfs_log_perror("Eeek! Failed to release allocated clusters"); ntfs_log_trace("Ignoring error and leaving behind wasted " "clusters.\n"); } /* Throw away the now unused runlist. */ free(na->rl); na->rl = NULL; /* Update in-memory struct ntfs_attr. */ NAttrClearNonResident(na); NAttrClearSparse(na); NAttrClearEncrypted(na); na->initialized_size = na->data_size; na->allocated_size = na->compressed_size = (na->data_size + 7) & ~7; na->compression_block_size = 0; na->compression_block_size_bits = na->compression_block_clusters = 0; return 0; } /* * If we are in the first extent, then set/clean sparse bit, * update allocated and compressed size. */ static int ntfs_attr_update_meta(ATTR_RECORD *a, ntfs_attr *na, MFT_RECORD *m, ntfs_attr_search_ctx *ctx) { int sparse, ret = 0; ntfs_log_trace("Entering for inode 0x%llx, attr 0x%x\n", (unsigned long long)na->ni->mft_no, na->type); if (a->lowest_vcn) goto out; a->allocated_size = cpu_to_sle64(na->allocated_size); /* Update sparse bit. */ sparse = ntfs_rl_sparse(na->rl); if (sparse == -1) { errno = EIO; goto error; } /* Attribute become sparse. */ if (sparse && !(a->flags & (ATTR_IS_SPARSE | ATTR_IS_COMPRESSED))) { /* * Move attribute to another mft record, if attribute is too * small to add compressed_size field to it and we have no * free space in the current mft record. */ if ((le32_to_cpu(a->length) - le16_to_cpu(a->mapping_pairs_offset) == 8) && !(le32_to_cpu(m->bytes_allocated) - le32_to_cpu(m->bytes_in_use))) { if (!NInoAttrList(na->ni)) { ntfs_attr_put_search_ctx(ctx); if (ntfs_inode_add_attrlist(na->ni)) goto leave; goto retry; } if (ntfs_attr_record_move_away(ctx, 8)) { ntfs_log_perror("Failed to move attribute"); goto error; } ntfs_attr_put_search_ctx(ctx); goto retry; } if (!(le32_to_cpu(a->length) - le16_to_cpu( a->mapping_pairs_offset))) { errno = EIO; ntfs_log_perror("Mapping pairs space is 0"); goto error; } NAttrSetSparse(na); a->flags |= ATTR_IS_SPARSE; a->compression_unit = STANDARD_COMPRESSION_UNIT; /* Windows set it so, even if attribute is not actually compressed. */ memmove((u8*)a + le16_to_cpu(a->name_offset) + 8, (u8*)a + le16_to_cpu(a->name_offset), a->name_length * sizeof(ntfschar)); a->name_offset = cpu_to_le16(le16_to_cpu(a->name_offset) + 8); a->mapping_pairs_offset = cpu_to_le16(le16_to_cpu(a->mapping_pairs_offset) + 8); } /* Attribute no longer sparse. */ if (!sparse && (a->flags & ATTR_IS_SPARSE) && !(a->flags & ATTR_IS_COMPRESSED)) { NAttrClearSparse(na); a->flags &= ~ATTR_IS_SPARSE; a->compression_unit = 0; memmove((u8*)a + le16_to_cpu(a->name_offset) - 8, (u8*)a + le16_to_cpu(a->name_offset), a->name_length * sizeof(ntfschar)); if (le16_to_cpu(a->name_offset) >= 8) a->name_offset = cpu_to_le16(le16_to_cpu(a->name_offset) - 8); a->mapping_pairs_offset = cpu_to_le16(le16_to_cpu(a->mapping_pairs_offset) - 8); } /* Update compressed size if required. */ if (sparse || (na->data_flags & ATTR_COMPRESSION_MASK)) { s64 new_compr_size; new_compr_size = ntfs_rl_get_compressed_size(na->ni->vol, na->rl); if (new_compr_size == -1) goto error; na->compressed_size = new_compr_size; a->compressed_size = cpu_to_sle64(new_compr_size); } /* * Set FILE_NAME dirty flag, to update sparse bit and * allocated size in the index. */ if (na->type == AT_DATA && na->name == AT_UNNAMED) { if (sparse || (na->data_flags & ATTR_COMPRESSION_MASK)) na->ni->allocated_size = na->compressed_size; else na->ni->allocated_size = na->allocated_size; NInoFileNameSetDirty(na->ni); } out: return ret; leave: ret = -1; goto out; /* return -1 */ retry: ret = -2; goto out; error: ret = -3; goto out; } #define NTFS_VCN_DELETE_MARK -2 /** * ntfs_attr_update_mapping_pairs_i - see ntfs_attr_update_mapping_pairs */ static int ntfs_attr_update_mapping_pairs_i(ntfs_attr *na, VCN from_vcn) { ntfs_attr_search_ctx *ctx; ntfs_inode *ni, *base_ni; MFT_RECORD *m; ATTR_RECORD *a; VCN stop_vcn; const runlist_element *stop_rl; int err, mp_size, cur_max_mp_size, exp_max_mp_size, ret = -1; BOOL finished_build; BOOL first_updated = FALSE; retry: if (!na || !na->rl) { errno = EINVAL; ntfs_log_perror("%s: na=%p", __FUNCTION__, na); return -1; } ntfs_log_trace("Entering for inode %llu, attr 0x%x\n", (unsigned long long)na->ni->mft_no, na->type); if (!NAttrNonResident(na)) { errno = EINVAL; ntfs_log_perror("%s: resident attribute", __FUNCTION__); return -1; } if (na->ni->nr_extents == -1) base_ni = na->ni->base_ni; else base_ni = na->ni; ctx = ntfs_attr_get_search_ctx(base_ni, NULL); if (!ctx) return -1; /* Fill attribute records with new mapping pairs. */ stop_vcn = 0; stop_rl = na->rl; finished_build = FALSE; while (!ntfs_attr_lookup(na->type, na->name, na->name_len, CASE_SENSITIVE, from_vcn, NULL, 0, ctx)) { a = ctx->attr; m = ctx->mrec; if (!a->lowest_vcn) first_updated = TRUE; /* * If runlist is updating not from the beginning, then set * @stop_vcn properly, i.e. to the lowest vcn of record that * contain @from_vcn. Also we do not need @from_vcn anymore, * set it to 0 to make ntfs_attr_lookup enumerate attributes. */ if (from_vcn) { LCN first_lcn; stop_vcn = sle64_to_cpu(a->lowest_vcn); from_vcn = 0; /* * Check whether the first run we need to update is * the last run in runlist, if so, then deallocate * all attrubute extents starting this one. */ first_lcn = ntfs_rl_vcn_to_lcn(na->rl, stop_vcn); if (first_lcn == LCN_EINVAL) { errno = EIO; ntfs_log_perror("Bad runlist"); goto put_err_out; } if (first_lcn == LCN_ENOENT || first_lcn == LCN_RL_NOT_MAPPED) finished_build = TRUE; } /* * Check whether we finished mapping pairs build, if so mark * extent as need to delete (by setting highest vcn to * NTFS_VCN_DELETE_MARK (-2), we shall check it later and * delete extent) and continue search. */ if (finished_build) { ntfs_log_trace("Mark attr 0x%x for delete in inode " "%lld.\n", (unsigned)le32_to_cpu(a->type), (long long)ctx->ntfs_ino->mft_no); a->highest_vcn = cpu_to_sle64(NTFS_VCN_DELETE_MARK); ntfs_inode_mark_dirty(ctx->ntfs_ino); continue; } switch (ntfs_attr_update_meta(a, na, m, ctx)) { case -1: return -1; case -2: goto retry; case -3: goto put_err_out; } /* * Determine maximum possible length of mapping pairs, * if we shall *not* expand space for mapping pairs. */ cur_max_mp_size = le32_to_cpu(a->length) - le16_to_cpu(a->mapping_pairs_offset); /* * Determine maximum possible length of mapping pairs in the * current mft record, if we shall expand space for mapping * pairs. */ exp_max_mp_size = le32_to_cpu(m->bytes_allocated) - le32_to_cpu(m->bytes_in_use) + cur_max_mp_size; /* Get the size for the rest of mapping pairs array. */ mp_size = ntfs_get_size_for_mapping_pairs(na->ni->vol, stop_rl, stop_vcn, exp_max_mp_size); if (mp_size <= 0) { ntfs_log_perror("%s: get MP size failed", __FUNCTION__); goto put_err_out; } /* Test mapping pairs for fitting in the current mft record. */ if (mp_size > exp_max_mp_size) { /* * Mapping pairs of $ATTRIBUTE_LIST attribute must fit * in the base mft record. Try to move out other * attributes and try again. */ if (na->type == AT_ATTRIBUTE_LIST) { ntfs_attr_put_search_ctx(ctx); if (ntfs_inode_free_space(na->ni, mp_size - cur_max_mp_size)) { ntfs_log_perror("Attribute list is too " "big. Defragment the " "volume\n"); return -1; } goto retry; } /* Add attribute list if it isn't present, and retry. */ if (!NInoAttrList(base_ni)) { ntfs_attr_put_search_ctx(ctx); if (ntfs_inode_add_attrlist(base_ni)) { ntfs_log_perror("Can not add attrlist"); return -1; } goto retry; } /* * Set mapping pairs size to maximum possible for this * mft record. We shall write the rest of mapping pairs * to another MFT records. */ mp_size = exp_max_mp_size; } /* Change space for mapping pairs if we need it. */ if (((mp_size + 7) & ~7) != cur_max_mp_size) { if (ntfs_attr_record_resize(m, a, le16_to_cpu(a->mapping_pairs_offset) + mp_size)) { errno = EIO; ntfs_log_perror("Failed to resize attribute"); goto put_err_out; } } /* Update lowest vcn. */ a->lowest_vcn = cpu_to_sle64(stop_vcn); ntfs_inode_mark_dirty(ctx->ntfs_ino); if ((ctx->ntfs_ino->nr_extents == -1 || NInoAttrList(ctx->ntfs_ino)) && ctx->attr->type != AT_ATTRIBUTE_LIST) { ctx->al_entry->lowest_vcn = cpu_to_sle64(stop_vcn); ntfs_attrlist_mark_dirty(ctx->ntfs_ino); } /* * Generate the new mapping pairs array directly into the * correct destination, i.e. the attribute record itself. */ if (!ntfs_mapping_pairs_build(na->ni->vol, (u8*)a + le16_to_cpu( a->mapping_pairs_offset), mp_size, na->rl, stop_vcn, &stop_rl)) finished_build = TRUE; if (stop_rl) stop_vcn = stop_rl->vcn; else stop_vcn = 0; if (!finished_build && errno != ENOSPC) { ntfs_log_perror("Failed to build mapping pairs"); goto put_err_out; } a->highest_vcn = cpu_to_sle64(stop_vcn - 1); } /* Check whether error occurred. */ if (errno != ENOENT) { ntfs_log_perror("%s: Attribute lookup failed", __FUNCTION__); goto put_err_out; } /* * If the base extent was skipped in the above process, * we still may have to update the sizes. */ if (!first_updated) { le16 spcomp; ntfs_attr_reinit_search_ctx(ctx); if (!ntfs_attr_lookup(na->type, na->name, na->name_len, CASE_SENSITIVE, 0, NULL, 0, ctx)) { a = ctx->attr; a->allocated_size = cpu_to_sle64(na->allocated_size); spcomp = na->data_flags & (ATTR_IS_COMPRESSED | ATTR_IS_SPARSE); if (spcomp) a->compressed_size = cpu_to_sle64(na->compressed_size); if ((na->type == AT_DATA) && (na->name == AT_UNNAMED)) { na->ni->allocated_size = (spcomp ? na->compressed_size : na->allocated_size); NInoFileNameSetDirty(na->ni); } } else { ntfs_log_error("Failed to update sizes in base extent\n"); goto put_err_out; } } /* Deallocate not used attribute extents and return with success. */ if (finished_build) { ntfs_attr_reinit_search_ctx(ctx); ntfs_log_trace("Deallocate marked extents.\n"); while (!ntfs_attr_lookup(na->type, na->name, na->name_len, CASE_SENSITIVE, 0, NULL, 0, ctx)) { if (sle64_to_cpu(ctx->attr->highest_vcn) != NTFS_VCN_DELETE_MARK) continue; /* Remove unused attribute record. */ if (ntfs_attr_record_rm(ctx)) { ntfs_log_perror("Could not remove unused attr"); goto put_err_out; } ntfs_attr_reinit_search_ctx(ctx); } if (errno != ENOENT) { ntfs_log_perror("%s: Attr lookup failed", __FUNCTION__); goto put_err_out; } ntfs_log_trace("Deallocate done.\n"); ntfs_attr_put_search_ctx(ctx); goto ok; } ntfs_attr_put_search_ctx(ctx); ctx = NULL; /* Allocate new MFT records for the rest of mapping pairs. */ while (1) { /* Calculate size of rest mapping pairs. */ mp_size = ntfs_get_size_for_mapping_pairs(na->ni->vol, na->rl, stop_vcn, INT_MAX); if (mp_size <= 0) { ntfs_log_perror("%s: get mp size failed", __FUNCTION__); goto put_err_out; } /* Allocate new mft record. */ ni = ntfs_mft_record_alloc(na->ni->vol, base_ni); if (!ni) { ntfs_log_perror("Could not allocate new MFT record"); goto put_err_out; } m = ni->mrec; /* * If mapping size exceed available space, set them to * possible maximum. */ cur_max_mp_size = le32_to_cpu(m->bytes_allocated) - le32_to_cpu(m->bytes_in_use) - (offsetof(ATTR_RECORD, compressed_size) + (((na->data_flags & ATTR_COMPRESSION_MASK) || NAttrSparse(na)) ? sizeof(a->compressed_size) : 0)) - ((sizeof(ntfschar) * na->name_len + 7) & ~7); if (mp_size > cur_max_mp_size) mp_size = cur_max_mp_size; /* Add attribute extent to new record. */ err = ntfs_non_resident_attr_record_add(ni, na->type, na->name, na->name_len, stop_vcn, mp_size, na->data_flags); if (err == -1) { err = errno; ntfs_log_perror("Could not add attribute extent"); if (ntfs_mft_record_free(na->ni->vol, ni)) ntfs_log_perror("Could not free MFT record"); errno = err; goto put_err_out; } a = (ATTR_RECORD*)((u8*)m + err); err = ntfs_mapping_pairs_build(na->ni->vol, (u8*)a + le16_to_cpu(a->mapping_pairs_offset), mp_size, na->rl, stop_vcn, &stop_rl); if (stop_rl) stop_vcn = stop_rl->vcn; else stop_vcn = 0; if (err < 0 && errno != ENOSPC) { err = errno; ntfs_log_perror("Failed to build MP"); if (ntfs_mft_record_free(na->ni->vol, ni)) ntfs_log_perror("Couldn't free MFT record"); errno = err; goto put_err_out; } a->highest_vcn = cpu_to_sle64(stop_vcn - 1); ntfs_inode_mark_dirty(ni); /* All mapping pairs has been written. */ if (!err) break; } ok: ret = 0; out: return ret; put_err_out: if (ctx) ntfs_attr_put_search_ctx(ctx); goto out; } #undef NTFS_VCN_DELETE_MARK /** * ntfs_attr_update_mapping_pairs - update mapping pairs for ntfs attribute * @na: non-resident ntfs open attribute for which we need update * @from_vcn: update runlist starting this VCN * * Build mapping pairs from @na->rl and write them to the disk. Also, this * function updates sparse bit, allocated and compressed size (allocates/frees * space for this field if required). * * @na->allocated_size should be set to correct value for the new runlist before * call to this function. Vice-versa @na->compressed_size will be calculated and * set to correct value during this function. * * FIXME: This function does not update sparse bit and compressed size correctly * if called with @from_vcn != 0. * * FIXME: Rewrite without using NTFS_VCN_DELETE_MARK define. * * On success return 0 and on error return -1 with errno set to the error code. * The following error codes are defined: * EINVAL - Invalid arguments passed. * ENOMEM - Not enough memory to complete operation. * ENOSPC - There is no enough space in base mft to resize $ATTRIBUTE_LIST * or there is no free MFT records left to allocate. */ int ntfs_attr_update_mapping_pairs(ntfs_attr *na, VCN from_vcn) { int ret; ntfs_log_enter("Entering\n"); ret = ntfs_attr_update_mapping_pairs_i(na, from_vcn); ntfs_log_leave("\n"); return ret; } /** * ntfs_non_resident_attr_shrink - shrink a non-resident, open ntfs attribute * @na: non-resident ntfs attribute to shrink * @newsize: new size (in bytes) to which to shrink the attribute * * Reduce the size of a non-resident, open ntfs attribute @na to @newsize bytes. * * On success return 0 and on error return -1 with errno set to the error code. * The following error codes are defined: * ENOMEM - Not enough memory to complete operation. * ERANGE - @newsize is not valid for the attribute type of @na. */ static int ntfs_non_resident_attr_shrink(ntfs_attr *na, const s64 newsize) { ntfs_volume *vol; ntfs_attr_search_ctx *ctx; VCN first_free_vcn; s64 nr_freed_clusters; int err; ntfs_log_trace("Inode 0x%llx attr 0x%x new size %lld\n", (unsigned long long) na->ni->mft_no, na->type, (long long)newsize); vol = na->ni->vol; /* * Check the attribute type and the corresponding minimum size * against @newsize and fail if @newsize is too small. */ if (ntfs_attr_size_bounds_check(vol, na->type, newsize) < 0) { if (errno == ERANGE) { ntfs_log_trace("Eeek! Size bounds check failed. " "Aborting...\n"); } else if (errno == ENOENT) errno = EIO; return -1; } /* The first cluster outside the new allocation. */ if (na->data_flags & ATTR_COMPRESSION_MASK) /* * For compressed files we must keep full compressions blocks, * but currently we do not decompress/recompress the last * block to truncate the data, so we may leave more allocated * clusters than really needed. */ first_free_vcn = (((newsize - 1) | (na->compression_block_size - 1)) + 1) >> vol->cluster_size_bits; else first_free_vcn = (newsize + vol->cluster_size - 1) >> vol->cluster_size_bits; /* * Compare the new allocation with the old one and only deallocate * clusters if there is a change. */ if ((na->allocated_size >> vol->cluster_size_bits) != first_free_vcn) { if (ntfs_attr_map_whole_runlist(na)) { ntfs_log_trace("Eeek! ntfs_attr_map_whole_runlist " "failed.\n"); return -1; } /* Deallocate all clusters starting with the first free one. */ nr_freed_clusters = ntfs_cluster_free(vol, na, first_free_vcn, -1); if (nr_freed_clusters < 0) { ntfs_log_trace("Eeek! Freeing of clusters failed. " "Aborting...\n"); return -1; } /* Truncate the runlist itself. */ if (ntfs_rl_truncate(&na->rl, first_free_vcn)) { /* * Failed to truncate the runlist, so just throw it * away, it will be mapped afresh on next use. */ free(na->rl); na->rl = NULL; ntfs_log_trace("Eeek! Run list truncation failed.\n"); return -1; } /* Prepare to mapping pairs update. */ na->allocated_size = first_free_vcn << vol->cluster_size_bits; /* Write mapping pairs for new runlist. */ if (ntfs_attr_update_mapping_pairs(na, 0 /*first_free_vcn*/)) { ntfs_log_trace("Eeek! Mapping pairs update failed. " "Leaving inconstant metadata. " "Run chkdsk.\n"); return -1; } } /* Get the first attribute record. */ ctx = ntfs_attr_get_search_ctx(na->ni, NULL); if (!ctx) return -1; if (ntfs_attr_lookup(na->type, na->name, na->name_len, CASE_SENSITIVE, 0, NULL, 0, ctx)) { err = errno; if (err == ENOENT) err = EIO; ntfs_log_trace("Eeek! Lookup of first attribute extent failed. " "Leaving inconstant metadata.\n"); goto put_err_out; } /* Update data and initialized size. */ na->data_size = newsize; ctx->attr->data_size = cpu_to_sle64(newsize); if (newsize < na->initialized_size) { na->initialized_size = newsize; ctx->attr->initialized_size = cpu_to_sle64(newsize); } /* Update data size in the index. */ if (na->ni->mrec->flags & MFT_RECORD_IS_DIRECTORY) { if (na->type == AT_INDEX_ROOT && na->name == NTFS_INDEX_I30) { na->ni->data_size = na->data_size; na->ni->allocated_size = na->allocated_size; set_nino_flag(na->ni,KnownSize); } } else { if (na->type == AT_DATA && na->name == AT_UNNAMED) { na->ni->data_size = na->data_size; NInoFileNameSetDirty(na->ni); } } /* If the attribute now has zero size, make it resident. */ if (!newsize) { if (ntfs_attr_make_resident(na, ctx)) { /* If couldn't make resident, just continue. */ if (errno != EPERM) ntfs_log_error("Failed to make attribute " "resident. Leaving as is...\n"); } } /* Set the inode dirty so it is written out later. */ ntfs_inode_mark_dirty(ctx->ntfs_ino); /* Done! */ ntfs_attr_put_search_ctx(ctx); return 0; put_err_out: ntfs_attr_put_search_ctx(ctx); errno = err; return -1; } /** * ntfs_non_resident_attr_expand - expand a non-resident, open ntfs attribute * @na: non-resident ntfs attribute to expand * @newsize: new size (in bytes) to which to expand the attribute * * Expand the size of a non-resident, open ntfs attribute @na to @newsize bytes, * by allocating new clusters. * * On success return 0 and on error return -1 with errno set to the error code. * The following error codes are defined: * ENOMEM - Not enough memory to complete operation. * ERANGE - @newsize is not valid for the attribute type of @na. * ENOSPC - There is no enough space in base mft to resize $ATTRIBUTE_LIST. */ static int ntfs_non_resident_attr_expand_i(ntfs_attr *na, const s64 newsize) { LCN lcn_seek_from; VCN first_free_vcn; ntfs_volume *vol; ntfs_attr_search_ctx *ctx; runlist *rl, *rln; s64 org_alloc_size; int err; ntfs_log_trace("Inode %lld, attr 0x%x, new size %lld old size %lld\n", (unsigned long long)na->ni->mft_no, na->type, (long long)newsize, (long long)na->data_size); vol = na->ni->vol; /* * Check the attribute type and the corresponding maximum size * against @newsize and fail if @newsize is too big. */ if (ntfs_attr_size_bounds_check(vol, na->type, newsize) < 0) { if (errno == ENOENT) errno = EIO; ntfs_log_perror("%s: bounds check failed", __FUNCTION__); return -1; } /* Save for future use. */ org_alloc_size = na->allocated_size; /* The first cluster outside the new allocation. */ first_free_vcn = (newsize + vol->cluster_size - 1) >> vol->cluster_size_bits; /* * Compare the new allocation with the old one and only allocate * clusters if there is a change. */ if ((na->allocated_size >> vol->cluster_size_bits) < first_free_vcn) { if (ntfs_attr_map_whole_runlist(na)) { ntfs_log_perror("ntfs_attr_map_whole_runlist failed"); return -1; } /* * If we extend $DATA attribute on NTFS 3+ volume, we can add * sparse runs instead of real allocation of clusters. */ if (na->type == AT_DATA && vol->major_ver >= 3) { rl = ntfs_malloc(0x1000); if (!rl) return -1; rl[0].vcn = (na->allocated_size >> vol->cluster_size_bits); rl[0].lcn = LCN_HOLE; rl[0].length = first_free_vcn - (na->allocated_size >> vol->cluster_size_bits); rl[1].vcn = first_free_vcn; rl[1].lcn = LCN_ENOENT; rl[1].length = 0; } else { /* * Determine first after last LCN of attribute. * We will start seek clusters from this LCN to avoid * fragmentation. If there are no valid LCNs in the * attribute let the cluster allocator choose the * starting LCN. */ lcn_seek_from = -1; if (na->rl->length) { /* Seek to the last run list element. */ for (rl = na->rl; (rl + 1)->length; rl++) ; /* * If the last LCN is a hole or similar seek * back to last valid LCN. */ while (rl->lcn < 0 && rl != na->rl) rl--; /* * Only set lcn_seek_from it the LCN is valid. */ if (rl->lcn >= 0) lcn_seek_from = rl->lcn + rl->length; } rl = ntfs_cluster_alloc(vol, na->allocated_size >> vol->cluster_size_bits, first_free_vcn - (na->allocated_size >> vol->cluster_size_bits), lcn_seek_from, DATA_ZONE); if (!rl) { ntfs_log_perror("Cluster allocation failed " "(%lld)", (long long)first_free_vcn - ((long long)na->allocated_size >> vol->cluster_size_bits)); return -1; } } /* Append new clusters to attribute runlist. */ rln = ntfs_runlists_merge(na->rl, rl); if (!rln) { /* Failed, free just allocated clusters. */ err = errno; ntfs_log_perror("Run list merge failed"); ntfs_cluster_free_from_rl(vol, rl); free(rl); errno = err; return -1; } na->rl = rln; /* Prepare to mapping pairs update. */ na->allocated_size = first_free_vcn << vol->cluster_size_bits; /* Write mapping pairs for new runlist. */ if (ntfs_attr_update_mapping_pairs(na, 0 /*na->allocated_size >> vol->cluster_size_bits*/)) { err = errno; ntfs_log_perror("Mapping pairs update failed"); goto rollback; } } ctx = ntfs_attr_get_search_ctx(na->ni, NULL); if (!ctx) { err = errno; if (na->allocated_size == org_alloc_size) { errno = err; return -1; } else goto rollback; } if (ntfs_attr_lookup(na->type, na->name, na->name_len, CASE_SENSITIVE, 0, NULL, 0, ctx)) { err = errno; ntfs_log_perror("Lookup of first attribute extent failed"); if (err == ENOENT) err = EIO; if (na->allocated_size != org_alloc_size) { ntfs_attr_put_search_ctx(ctx); goto rollback; } else goto put_err_out; } /* Update data size. */ na->data_size = newsize; ctx->attr->data_size = cpu_to_sle64(newsize); /* Update data size in the index. */ if (na->ni->mrec->flags & MFT_RECORD_IS_DIRECTORY) { if (na->type == AT_INDEX_ROOT && na->name == NTFS_INDEX_I30) { na->ni->data_size = na->data_size; na->ni->allocated_size = na->allocated_size; set_nino_flag(na->ni,KnownSize); } } else { if (na->type == AT_DATA && na->name == AT_UNNAMED) { na->ni->data_size = na->data_size; NInoFileNameSetDirty(na->ni); } } /* Set the inode dirty so it is written out later. */ ntfs_inode_mark_dirty(ctx->ntfs_ino); /* Done! */ ntfs_attr_put_search_ctx(ctx); return 0; rollback: /* Free allocated clusters. */ if (ntfs_cluster_free(vol, na, org_alloc_size >> vol->cluster_size_bits, -1) < 0) { err = EIO; ntfs_log_perror("Leaking clusters"); } /* Now, truncate the runlist itself. */ if (ntfs_rl_truncate(&na->rl, org_alloc_size >> vol->cluster_size_bits)) { /* * Failed to truncate the runlist, so just throw it away, it * will be mapped afresh on next use. */ free(na->rl); na->rl = NULL; ntfs_log_perror("Couldn't truncate runlist. Rollback failed"); } else { /* Prepare to mapping pairs update. */ na->allocated_size = org_alloc_size; /* Restore mapping pairs. */ if (ntfs_attr_update_mapping_pairs(na, 0 /*na->allocated_size >> vol->cluster_size_bits*/)) { ntfs_log_perror("Failed to restore old mapping pairs"); } } errno = err; return -1; put_err_out: ntfs_attr_put_search_ctx(ctx); errno = err; return -1; } static int ntfs_non_resident_attr_expand(ntfs_attr *na, const s64 newsize) { int ret; ntfs_log_enter("Entering\n"); ret = ntfs_non_resident_attr_expand_i(na, newsize); ntfs_log_leave("\n"); return ret; } /** * ntfs_attr_truncate - resize an ntfs attribute * @na: open ntfs attribute to resize * @newsize: new size (in bytes) to which to resize the attribute * * Change the size of an open ntfs attribute @na to @newsize bytes. If the * attribute is made bigger and the attribute is resident the newly * "allocated" space is cleared and if the attribute is non-resident the * newly allocated space is marked as not initialised and no real allocation * on disk is performed. * * On success return 0. * On error return values are: * STATUS_RESIDENT_ATTRIBUTE_FILLED_MFT * STATUS_ERROR - otherwise * The following error codes are defined: * EINVAL - Invalid arguments were passed to the function. * EOPNOTSUPP - The desired resize is not implemented yet. * EACCES - Encrypted attribute. */ int ntfs_attr_truncate(ntfs_attr *na, const s64 newsize) { int ret = STATUS_ERROR; s64 fullsize; BOOL compressed; if (!na || newsize < 0 || (na->ni->mft_no == FILE_MFT && na->type == AT_DATA)) { ntfs_log_trace("Invalid arguments passed.\n"); errno = EINVAL; return STATUS_ERROR; } ntfs_log_enter("Entering for inode %lld, attr 0x%x, size %lld\n", (unsigned long long)na->ni->mft_no, na->type, (long long)newsize); if (na->data_size == newsize) { ntfs_log_trace("Size is already ok\n"); ret = STATUS_OK; goto out; } /* * Encrypted attributes are not supported. We return access denied, * which is what Windows NT4 does, too. */ if (na->data_flags & ATTR_IS_ENCRYPTED) { errno = EACCES; ntfs_log_trace("Cannot truncate encrypted attribute\n"); goto out; } /* * TODO: Implement making handling of compressed attributes. * Currently we can only expand the attribute or delete it, * and only for ATTR_IS_COMPRESSED. This is however possible * for resident attributes when there is no open fuse context * (important case : $INDEX_ROOT:$I30) */ compressed = (na->data_flags & ATTR_COMPRESSION_MASK) != const_cpu_to_le16(0); if (compressed && NAttrNonResident(na) && ((na->data_flags & ATTR_COMPRESSION_MASK) != ATTR_IS_COMPRESSED)) { errno = EOPNOTSUPP; ntfs_log_perror("Failed to truncate compressed attribute"); goto out; } if (NAttrNonResident(na)) { /* * For compressed data, the last block must be fully * allocated, and we do not know the size of compression * block until the attribute has been made non-resident. * Moreover we can only process a single compression * block at a time (from where we are about to write), * so we silently do not allocate more. * * Note : do not request upsizing of compressed files * unless being able to face the consequences ! */ if (compressed && newsize && (newsize > na->data_size)) fullsize = (na->initialized_size | (na->compression_block_size - 1)) + 1; else fullsize = newsize; if (fullsize > na->data_size) ret = ntfs_non_resident_attr_expand(na, fullsize); else ret = ntfs_non_resident_attr_shrink(na, fullsize); } else ret = ntfs_resident_attr_resize(na, newsize); out: ntfs_log_leave("Return status %d\n", ret); return ret; } /* * Stuff a hole in a compressed file * * An unallocated hole must be aligned on compression block size. * If needed current block and target block are stuffed with zeroes. * * Returns 0 if succeeded, * -1 if it failed (as explained in errno) */ static int stuff_hole(ntfs_attr *na, const s64 pos) { s64 size; s64 begin_size; s64 end_size; char *buf; int ret; ret = 0; /* * If the attribute is resident, the compression block size * is not defined yet and we can make no decision. * So we first try resizing to the target and if the * attribute is still resident, we're done */ if (!NAttrNonResident(na)) { ret = ntfs_resident_attr_resize(na, pos); if (!ret && !NAttrNonResident(na)) na->initialized_size = na->data_size = pos; } if (!ret && NAttrNonResident(na)) { /* does the hole span over several compression block ? */ if ((pos ^ na->initialized_size) & ~(na->compression_block_size - 1)) { begin_size = ((na->initialized_size - 1) | (na->compression_block_size - 1)) + 1 - na->initialized_size; end_size = pos & (na->compression_block_size - 1); size = (begin_size > end_size ? begin_size : end_size); } else { /* short stuffing in a single compression block */ begin_size = size = pos - na->initialized_size; end_size = 0; } if (size) buf = (char*)ntfs_malloc(size); else buf = (char*)NULL; if (buf || !size) { memset(buf,0,size); /* stuff into current block */ if (begin_size && (ntfs_attr_pwrite(na, na->initialized_size, begin_size, buf) != begin_size)) ret = -1; /* create an unstuffed hole */ if (!ret && ((na->initialized_size + end_size) < pos) && ntfs_non_resident_attr_expand(na, pos - end_size)) ret = -1; else na->initialized_size = na->data_size = pos - end_size; /* stuff into the target block */ if (!ret && end_size && (ntfs_attr_pwrite(na, na->initialized_size, end_size, buf) != end_size)) ret = -1; if (buf) free(buf); } else ret = -1; } /* make absolutely sure we have reached the target */ if (!ret && (na->initialized_size != pos)) { ntfs_log_error("Failed to stuff a compressed file" "target %lld reached %lld\n", (long long)pos, (long long)na->initialized_size); errno = EIO; ret = -1; } return (ret); } /** * ntfs_attr_readall - read the entire data from an ntfs attribute * @ni: open ntfs inode in which the ntfs attribute resides * @type: attribute type * @name: attribute name in little endian Unicode or AT_UNNAMED or NULL * @name_len: length of attribute @name in Unicode characters (if @name given) * @data_size: if non-NULL then store here the data size * * This function will read the entire content of an ntfs attribute. * If @name is AT_UNNAMED then look specifically for an unnamed attribute. * If @name is NULL then the attribute could be either named or not. * In both those cases @name_len is not used at all. * * On success a buffer is allocated with the content of the attribute * and which needs to be freed when it's not needed anymore. If the * @data_size parameter is non-NULL then the data size is set there. * * On error NULL is returned with errno set to the error code. */ void *ntfs_attr_readall(ntfs_inode *ni, const ATTR_TYPES type, ntfschar *name, u32 name_len, s64 *data_size) { ntfs_attr *na; void *data, *ret = NULL; s64 size; ntfs_log_enter("Entering\n"); na = ntfs_attr_open(ni, type, name, name_len); if (!na) { ntfs_log_perror("ntfs_attr_open failed"); goto err_exit; } data = ntfs_malloc(na->data_size); if (!data) goto out; size = ntfs_attr_pread(na, 0, na->data_size, data); if (size != na->data_size) { ntfs_log_perror("ntfs_attr_pread failed"); free(data); goto out; } ret = data; if (data_size) *data_size = size; out: ntfs_attr_close(na); err_exit: ntfs_log_leave("\n"); return ret; } int ntfs_attr_exist(ntfs_inode *ni, const ATTR_TYPES type, ntfschar *name, u32 name_len) { ntfs_attr_search_ctx *ctx; int ret; ntfs_log_trace("Entering\n"); ctx = ntfs_attr_get_search_ctx(ni, NULL); if (!ctx) return 0; ret = ntfs_attr_lookup(type, name, name_len, CASE_SENSITIVE, 0, NULL, 0, ctx); ntfs_attr_put_search_ctx(ctx); return !ret; } int ntfs_attr_remove(ntfs_inode *ni, const ATTR_TYPES type, ntfschar *name, u32 name_len) { ntfs_attr *na; int ret; ntfs_log_trace("Entering\n"); if (!ni) { ntfs_log_error("%s: NULL inode pointer", __FUNCTION__); errno = EINVAL; return -1; } na = ntfs_attr_open(ni, type, name, name_len); if (!na) { /* do not log removal of non-existent stream */ if (type != AT_DATA) { ntfs_log_perror("Failed to open attribute 0x%02x of inode " "0x%llx", type, (unsigned long long)ni->mft_no); } return -1; } ret = ntfs_attr_rm(na); if (ret) ntfs_log_perror("Failed to remove attribute 0x%02x of inode " "0x%llx", type, (unsigned long long)ni->mft_no); ntfs_attr_close(na); return ret; } /* Below macros are 32-bit ready. */ #define BCX(x) ((x) - (((x) >> 1) & 0x77777777) - \ (((x) >> 2) & 0x33333333) - \ (((x) >> 3) & 0x11111111)) #define BITCOUNT(x) (((BCX(x) + (BCX(x) >> 4)) & 0x0F0F0F0F) % 255) static u8 *ntfs_init_lut256(void) { int i; u8 *lut; lut = ntfs_malloc(256); if (lut) for(i = 0; i < 256; i++) *(lut + i) = 8 - BITCOUNT(i); return lut; } s64 ntfs_attr_get_free_bits(ntfs_attr *na) { u8 *buf, *lut; s64 br = 0; s64 total = 0; s64 nr_free = 0; lut = ntfs_init_lut256(); if (!lut) return -1; buf = ntfs_malloc(65536); if (!buf) goto out; while (1) { u32 *p; br = ntfs_attr_pread(na, total, 65536, buf); if (br <= 0) break; total += br; p = (u32 *)buf + br / 4 - 1; for (; (u8 *)p >= buf; p--) { nr_free += lut[ *p & 255] + lut[(*p >> 8) & 255] + lut[(*p >> 16) & 255] + lut[(*p >> 24) ]; } switch (br % 4) { case 3: nr_free += lut[*(buf + br - 3)]; case 2: nr_free += lut[*(buf + br - 2)]; case 1: nr_free += lut[*(buf + br - 1)]; } } free(buf); out: free(lut); if (!total || br < 0) return -1; return nr_free; }