linux/net/sunrpc/auth_gss/gss_krb5_crypto.c
Jens Axboe c46f2334c8 [SG] Get rid of __sg_mark_end()
sg_mark_end() overwrites the page_link information, but all users want
__sg_mark_end() behaviour where we just set the end bit. That is the most
natural way to use the sg list, since you'll fill it in and then mark the
end point.

So change sg_mark_end() to only set the termination bit. Add a sg_magic
debug check as well, and clear a chain pointer if it is set.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-11-02 08:47:06 +01:00

339 lines
8.3 KiB
C

/*
* linux/net/sunrpc/gss_krb5_crypto.c
*
* Copyright (c) 2000 The Regents of the University of Michigan.
* All rights reserved.
*
* Andy Adamson <andros@umich.edu>
* Bruce Fields <bfields@umich.edu>
*/
/*
* Copyright (C) 1998 by the FundsXpress, INC.
*
* All rights reserved.
*
* Export of this software from the United States of America may require
* a specific license from the United States Government. It is the
* responsibility of any person or organization contemplating export to
* obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of FundsXpress. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. FundsXpress makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
#include <linux/err.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/scatterlist.h>
#include <linux/crypto.h>
#include <linux/highmem.h>
#include <linux/pagemap.h>
#include <linux/sunrpc/gss_krb5.h>
#include <linux/sunrpc/xdr.h>
#ifdef RPC_DEBUG
# define RPCDBG_FACILITY RPCDBG_AUTH
#endif
u32
krb5_encrypt(
struct crypto_blkcipher *tfm,
void * iv,
void * in,
void * out,
int length)
{
u32 ret = -EINVAL;
struct scatterlist sg[1];
u8 local_iv[16] = {0};
struct blkcipher_desc desc = { .tfm = tfm, .info = local_iv };
if (length % crypto_blkcipher_blocksize(tfm) != 0)
goto out;
if (crypto_blkcipher_ivsize(tfm) > 16) {
dprintk("RPC: gss_k5encrypt: tfm iv size to large %d\n",
crypto_blkcipher_ivsize(tfm));
goto out;
}
if (iv)
memcpy(local_iv, iv, crypto_blkcipher_ivsize(tfm));
memcpy(out, in, length);
sg_init_one(sg, out, length);
ret = crypto_blkcipher_encrypt_iv(&desc, sg, sg, length);
out:
dprintk("RPC: krb5_encrypt returns %d\n", ret);
return ret;
}
EXPORT_SYMBOL(krb5_encrypt);
u32
krb5_decrypt(
struct crypto_blkcipher *tfm,
void * iv,
void * in,
void * out,
int length)
{
u32 ret = -EINVAL;
struct scatterlist sg[1];
u8 local_iv[16] = {0};
struct blkcipher_desc desc = { .tfm = tfm, .info = local_iv };
if (length % crypto_blkcipher_blocksize(tfm) != 0)
goto out;
if (crypto_blkcipher_ivsize(tfm) > 16) {
dprintk("RPC: gss_k5decrypt: tfm iv size to large %d\n",
crypto_blkcipher_ivsize(tfm));
goto out;
}
if (iv)
memcpy(local_iv,iv, crypto_blkcipher_ivsize(tfm));
memcpy(out, in, length);
sg_init_one(sg, out, length);
ret = crypto_blkcipher_decrypt_iv(&desc, sg, sg, length);
out:
dprintk("RPC: gss_k5decrypt returns %d\n",ret);
return ret;
}
EXPORT_SYMBOL(krb5_decrypt);
static int
checksummer(struct scatterlist *sg, void *data)
{
struct hash_desc *desc = data;
return crypto_hash_update(desc, sg, sg->length);
}
/* checksum the plaintext data and hdrlen bytes of the token header */
s32
make_checksum(char *cksumname, char *header, int hdrlen, struct xdr_buf *body,
int body_offset, struct xdr_netobj *cksum)
{
struct hash_desc desc; /* XXX add to ctx? */
struct scatterlist sg[1];
int err;
desc.tfm = crypto_alloc_hash(cksumname, 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(desc.tfm))
return GSS_S_FAILURE;
cksum->len = crypto_hash_digestsize(desc.tfm);
desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
err = crypto_hash_init(&desc);
if (err)
goto out;
sg_init_one(sg, header, hdrlen);
err = crypto_hash_update(&desc, sg, hdrlen);
if (err)
goto out;
err = xdr_process_buf(body, body_offset, body->len - body_offset,
checksummer, &desc);
if (err)
goto out;
err = crypto_hash_final(&desc, cksum->data);
out:
crypto_free_hash(desc.tfm);
return err ? GSS_S_FAILURE : 0;
}
EXPORT_SYMBOL(make_checksum);
struct encryptor_desc {
u8 iv[8]; /* XXX hard-coded blocksize */
struct blkcipher_desc desc;
int pos;
struct xdr_buf *outbuf;
struct page **pages;
struct scatterlist infrags[4];
struct scatterlist outfrags[4];
int fragno;
int fraglen;
};
static int
encryptor(struct scatterlist *sg, void *data)
{
struct encryptor_desc *desc = data;
struct xdr_buf *outbuf = desc->outbuf;
struct page *in_page;
int thislen = desc->fraglen + sg->length;
int fraglen, ret;
int page_pos;
/* Worst case is 4 fragments: head, end of page 1, start
* of page 2, tail. Anything more is a bug. */
BUG_ON(desc->fragno > 3);
page_pos = desc->pos - outbuf->head[0].iov_len;
if (page_pos >= 0 && page_pos < outbuf->page_len) {
/* pages are not in place: */
int i = (page_pos + outbuf->page_base) >> PAGE_CACHE_SHIFT;
in_page = desc->pages[i];
} else {
in_page = sg_page(sg);
}
sg_set_page(&desc->infrags[desc->fragno], in_page, sg->length,
sg->offset);
sg_set_page(&desc->outfrags[desc->fragno], sg_page(sg), sg->length,
sg->offset);
desc->fragno++;
desc->fraglen += sg->length;
desc->pos += sg->length;
fraglen = thislen & 7; /* XXX hardcoded blocksize */
thislen -= fraglen;
if (thislen == 0)
return 0;
sg_mark_end(&desc->infrags[desc->fragno - 1]);
sg_mark_end(&desc->outfrags[desc->fragno - 1]);
ret = crypto_blkcipher_encrypt_iv(&desc->desc, desc->outfrags,
desc->infrags, thislen);
if (ret)
return ret;
sg_init_table(desc->infrags, 4);
sg_init_table(desc->outfrags, 4);
if (fraglen) {
sg_set_page(&desc->outfrags[0], sg_page(sg), fraglen,
sg->offset + sg->length - fraglen);
desc->infrags[0] = desc->outfrags[0];
sg_assign_page(&desc->infrags[0], in_page);
desc->fragno = 1;
desc->fraglen = fraglen;
} else {
desc->fragno = 0;
desc->fraglen = 0;
}
return 0;
}
int
gss_encrypt_xdr_buf(struct crypto_blkcipher *tfm, struct xdr_buf *buf,
int offset, struct page **pages)
{
int ret;
struct encryptor_desc desc;
BUG_ON((buf->len - offset) % crypto_blkcipher_blocksize(tfm) != 0);
memset(desc.iv, 0, sizeof(desc.iv));
desc.desc.tfm = tfm;
desc.desc.info = desc.iv;
desc.desc.flags = 0;
desc.pos = offset;
desc.outbuf = buf;
desc.pages = pages;
desc.fragno = 0;
desc.fraglen = 0;
sg_init_table(desc.infrags, 4);
sg_init_table(desc.outfrags, 4);
ret = xdr_process_buf(buf, offset, buf->len - offset, encryptor, &desc);
return ret;
}
EXPORT_SYMBOL(gss_encrypt_xdr_buf);
struct decryptor_desc {
u8 iv[8]; /* XXX hard-coded blocksize */
struct blkcipher_desc desc;
struct scatterlist frags[4];
int fragno;
int fraglen;
};
static int
decryptor(struct scatterlist *sg, void *data)
{
struct decryptor_desc *desc = data;
int thislen = desc->fraglen + sg->length;
int fraglen, ret;
/* Worst case is 4 fragments: head, end of page 1, start
* of page 2, tail. Anything more is a bug. */
BUG_ON(desc->fragno > 3);
sg_set_page(&desc->frags[desc->fragno], sg_page(sg), sg->length,
sg->offset);
desc->fragno++;
desc->fraglen += sg->length;
fraglen = thislen & 7; /* XXX hardcoded blocksize */
thislen -= fraglen;
if (thislen == 0)
return 0;
sg_mark_end(&desc->frags[desc->fragno - 1]);
ret = crypto_blkcipher_decrypt_iv(&desc->desc, desc->frags,
desc->frags, thislen);
if (ret)
return ret;
sg_init_table(desc->frags, 4);
if (fraglen) {
sg_set_page(&desc->frags[0], sg_page(sg), fraglen,
sg->offset + sg->length - fraglen);
desc->fragno = 1;
desc->fraglen = fraglen;
} else {
desc->fragno = 0;
desc->fraglen = 0;
}
return 0;
}
int
gss_decrypt_xdr_buf(struct crypto_blkcipher *tfm, struct xdr_buf *buf,
int offset)
{
struct decryptor_desc desc;
/* XXXJBF: */
BUG_ON((buf->len - offset) % crypto_blkcipher_blocksize(tfm) != 0);
memset(desc.iv, 0, sizeof(desc.iv));
desc.desc.tfm = tfm;
desc.desc.info = desc.iv;
desc.desc.flags = 0;
desc.fragno = 0;
desc.fraglen = 0;
sg_init_table(desc.frags, 4);
return xdr_process_buf(buf, offset, buf->len - offset, decryptor, &desc);
}
EXPORT_SYMBOL(gss_decrypt_xdr_buf);