/* * Copyright (c) 2004 The Regents of the University of Michigan. * All rights reserved. * * Andy Adamson <andros@citi.umich.edu> * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */ #include <linux/file.h> #include <linux/slab.h> #include <linux/namei.h> #include <linux/crypto.h> #include <linux/sched.h> #include "nfsd.h" #include "state.h" #include "vfs.h" #define NFSDDBG_FACILITY NFSDDBG_PROC /* Globals */ static struct file *rec_file; static char user_recovery_dirname[PATH_MAX] = "/var/lib/nfs/v4recovery"; static int nfs4_save_creds(const struct cred **original_creds) { struct cred *new; new = prepare_creds(); if (!new) return -ENOMEM; new->fsuid = 0; new->fsgid = 0; *original_creds = override_creds(new); put_cred(new); return 0; } static void nfs4_reset_creds(const struct cred *original) { revert_creds(original); } static void md5_to_hex(char *out, char *md5) { int i; for (i=0; i<16; i++) { unsigned char c = md5[i]; *out++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)*('a'-'9'-1); *out++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)*('a'-'9'-1); } *out = '\0'; } __be32 nfs4_make_rec_clidname(char *dname, struct xdr_netobj *clname) { struct xdr_netobj cksum; struct hash_desc desc; struct scatterlist sg; __be32 status = nfserr_jukebox; dprintk("NFSD: nfs4_make_rec_clidname for %.*s\n", clname->len, clname->data); desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; desc.tfm = crypto_alloc_hash("md5", 0, CRYPTO_ALG_ASYNC); if (IS_ERR(desc.tfm)) goto out_no_tfm; cksum.len = crypto_hash_digestsize(desc.tfm); cksum.data = kmalloc(cksum.len, GFP_KERNEL); if (cksum.data == NULL) goto out; sg_init_one(&sg, clname->data, clname->len); if (crypto_hash_digest(&desc, &sg, sg.length, cksum.data)) goto out; md5_to_hex(dname, cksum.data); status = nfs_ok; out: kfree(cksum.data); crypto_free_hash(desc.tfm); out_no_tfm: return status; } void nfsd4_create_clid_dir(struct nfs4_client *clp) { const struct cred *original_cred; char *dname = clp->cl_recdir; struct dentry *dir, *dentry; int status; dprintk("NFSD: nfsd4_create_clid_dir for \"%s\"\n", dname); if (clp->cl_firststate) return; clp->cl_firststate = 1; if (!rec_file) return; status = nfs4_save_creds(&original_cred); if (status < 0) return; dir = rec_file->f_path.dentry; /* lock the parent */ mutex_lock(&dir->d_inode->i_mutex); dentry = lookup_one_len(dname, dir, HEXDIR_LEN-1); if (IS_ERR(dentry)) { status = PTR_ERR(dentry); goto out_unlock; } if (dentry->d_inode) /* * In the 4.1 case, where we're called from * reclaim_complete(), records from the previous reboot * may still be left, so this is OK. * * In the 4.0 case, we should never get here; but we may * as well be forgiving and just succeed silently. */ goto out_put; status = mnt_want_write_file(rec_file); if (status) goto out_put; status = vfs_mkdir(dir->d_inode, dentry, S_IRWXU); mnt_drop_write_file(rec_file); out_put: dput(dentry); out_unlock: mutex_unlock(&dir->d_inode->i_mutex); if (status == 0) vfs_fsync(rec_file, 0); else printk(KERN_ERR "NFSD: failed to write recovery record" " (err %d); please check that %s exists" " and is writeable", status, user_recovery_dirname); nfs4_reset_creds(original_cred); } typedef int (recdir_func)(struct dentry *, struct dentry *); struct name_list { char name[HEXDIR_LEN]; struct list_head list; }; static int nfsd4_build_namelist(void *arg, const char *name, int namlen, loff_t offset, u64 ino, unsigned int d_type) { struct list_head *names = arg; struct name_list *entry; if (namlen != HEXDIR_LEN - 1) return 0; entry = kmalloc(sizeof(struct name_list), GFP_KERNEL); if (entry == NULL) return -ENOMEM; memcpy(entry->name, name, HEXDIR_LEN - 1); entry->name[HEXDIR_LEN - 1] = '\0'; list_add(&entry->list, names); return 0; } static int nfsd4_list_rec_dir(recdir_func *f) { const struct cred *original_cred; struct dentry *dir = rec_file->f_path.dentry; LIST_HEAD(names); int status; status = nfs4_save_creds(&original_cred); if (status < 0) return status; status = vfs_llseek(rec_file, 0, SEEK_SET); if (status < 0) { nfs4_reset_creds(original_cred); return status; } status = vfs_readdir(rec_file, nfsd4_build_namelist, &names); mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT); while (!list_empty(&names)) { struct name_list *entry; entry = list_entry(names.next, struct name_list, list); if (!status) { struct dentry *dentry; dentry = lookup_one_len(entry->name, dir, HEXDIR_LEN-1); if (IS_ERR(dentry)) { status = PTR_ERR(dentry); break; } status = f(dir, dentry); dput(dentry); } list_del(&entry->list); kfree(entry); } mutex_unlock(&dir->d_inode->i_mutex); nfs4_reset_creds(original_cred); return status; } static int nfsd4_unlink_clid_dir(char *name, int namlen) { struct dentry *dir, *dentry; int status; dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name); dir = rec_file->f_path.dentry; mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT); dentry = lookup_one_len(name, dir, namlen); if (IS_ERR(dentry)) { status = PTR_ERR(dentry); goto out_unlock; } status = -ENOENT; if (!dentry->d_inode) goto out; status = vfs_rmdir(dir->d_inode, dentry); out: dput(dentry); out_unlock: mutex_unlock(&dir->d_inode->i_mutex); return status; } void nfsd4_remove_clid_dir(struct nfs4_client *clp) { const struct cred *original_cred; int status; if (!rec_file || !clp->cl_firststate) return; status = mnt_want_write_file(rec_file); if (status) goto out; clp->cl_firststate = 0; status = nfs4_save_creds(&original_cred); if (status < 0) goto out; status = nfsd4_unlink_clid_dir(clp->cl_recdir, HEXDIR_LEN-1); nfs4_reset_creds(original_cred); if (status == 0) vfs_fsync(rec_file, 0); mnt_drop_write_file(rec_file); out: if (status) printk("NFSD: Failed to remove expired client state directory" " %.*s\n", HEXDIR_LEN, clp->cl_recdir); return; } static int purge_old(struct dentry *parent, struct dentry *child) { int status; if (nfs4_has_reclaimed_state(child->d_name.name, false)) return 0; status = vfs_rmdir(parent->d_inode, child); if (status) printk("failed to remove client recovery directory %s\n", child->d_name.name); /* Keep trying, success or failure: */ return 0; } void nfsd4_recdir_purge_old(void) { int status; if (!rec_file) return; status = mnt_want_write_file(rec_file); if (status) goto out; status = nfsd4_list_rec_dir(purge_old); if (status == 0) vfs_fsync(rec_file, 0); mnt_drop_write_file(rec_file); out: if (status) printk("nfsd4: failed to purge old clients from recovery" " directory %s\n", rec_file->f_path.dentry->d_name.name); } static int load_recdir(struct dentry *parent, struct dentry *child) { if (child->d_name.len != HEXDIR_LEN - 1) { printk("nfsd4: illegal name %s in recovery directory\n", child->d_name.name); /* Keep trying; maybe the others are OK: */ return 0; } nfs4_client_to_reclaim(child->d_name.name); return 0; } int nfsd4_recdir_load(void) { int status; if (!rec_file) return 0; status = nfsd4_list_rec_dir(load_recdir); if (status) printk("nfsd4: failed loading clients from recovery" " directory %s\n", rec_file->f_path.dentry->d_name.name); return status; } /* * Hold reference to the recovery directory. */ void nfsd4_init_recdir() { const struct cred *original_cred; int status; printk("NFSD: Using %s as the NFSv4 state recovery directory\n", user_recovery_dirname); BUG_ON(rec_file); status = nfs4_save_creds(&original_cred); if (status < 0) { printk("NFSD: Unable to change credentials to find recovery" " directory: error %d\n", status); return; } rec_file = filp_open(user_recovery_dirname, O_RDONLY | O_DIRECTORY, 0); if (IS_ERR(rec_file)) { printk("NFSD: unable to find recovery directory %s\n", user_recovery_dirname); rec_file = NULL; } nfs4_reset_creds(original_cred); } void nfsd4_shutdown_recdir(void) { if (!rec_file) return; fput(rec_file); rec_file = NULL; } /* * Change the NFSv4 recovery directory to recdir. */ int nfs4_reset_recoverydir(char *recdir) { int status; struct path path; status = kern_path(recdir, LOOKUP_FOLLOW, &path); if (status) return status; status = -ENOTDIR; if (S_ISDIR(path.dentry->d_inode->i_mode)) { strcpy(user_recovery_dirname, recdir); status = 0; } path_put(&path); return status; } char * nfs4_recoverydir(void) { return user_recovery_dirname; }