linux-stable/crypto/ahash.c

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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Asynchronous Cryptographic Hash operations.
*
* This is the asynchronous version of hash.c with notification of
* completion via a callback.
*
* Copyright (c) 2008 Loc Ho <lho@amcc.com>
*/
#include <crypto/scatterwalk.h>
#include <linux/cryptouser.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/seq_file.h>
#include <linux/string.h>
#include <net/netlink.h>
#include "hash.h"
static const struct crypto_type crypto_ahash_type;
struct ahash_request_priv {
crypto_completion_t complete;
void *data;
u8 *result;
u32 flags;
void *ubuf[] CRYPTO_MINALIGN_ATTR;
};
static int hash_walk_next(struct crypto_hash_walk *walk)
{
unsigned int alignmask = walk->alignmask;
unsigned int offset = walk->offset;
unsigned int nbytes = min(walk->entrylen,
((unsigned int)(PAGE_SIZE)) - offset);
walk->data = kmap_local_page(walk->pg);
walk->data += offset;
if (offset & alignmask) {
unsigned int unaligned = alignmask + 1 - (offset & alignmask);
if (nbytes > unaligned)
nbytes = unaligned;
}
walk->entrylen -= nbytes;
return nbytes;
}
static int hash_walk_new_entry(struct crypto_hash_walk *walk)
{
struct scatterlist *sg;
sg = walk->sg;
walk->offset = sg->offset;
walk->pg = sg_page(walk->sg) + (walk->offset >> PAGE_SHIFT);
walk->offset = offset_in_page(walk->offset);
walk->entrylen = sg->length;
if (walk->entrylen > walk->total)
walk->entrylen = walk->total;
walk->total -= walk->entrylen;
return hash_walk_next(walk);
}
int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err)
{
unsigned int alignmask = walk->alignmask;
walk->data -= walk->offset;
if (walk->entrylen && (walk->offset & alignmask) && !err) {
unsigned int nbytes;
walk->offset = ALIGN(walk->offset, alignmask + 1);
nbytes = min(walk->entrylen,
(unsigned int)(PAGE_SIZE - walk->offset));
if (nbytes) {
walk->entrylen -= nbytes;
walk->data += walk->offset;
return nbytes;
}
}
kunmap_local(walk->data);
crypto_yield(walk->flags);
if (err)
return err;
if (walk->entrylen) {
walk->offset = 0;
walk->pg++;
return hash_walk_next(walk);
}
if (!walk->total)
return 0;
walk->sg = sg_next(walk->sg);
return hash_walk_new_entry(walk);
}
EXPORT_SYMBOL_GPL(crypto_hash_walk_done);
int crypto_hash_walk_first(struct ahash_request *req,
struct crypto_hash_walk *walk)
{
walk->total = req->nbytes;
if (!walk->total) {
walk->entrylen = 0;
return 0;
}
walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
walk->sg = req->src;
walk->flags = req->base.flags;
return hash_walk_new_entry(walk);
}
EXPORT_SYMBOL_GPL(crypto_hash_walk_first);
static int ahash_setkey_unaligned(struct crypto_ahash *tfm, const u8 *key,
unsigned int keylen)
{
unsigned long alignmask = crypto_ahash_alignmask(tfm);
int ret;
u8 *buffer, *alignbuffer;
unsigned long absize;
absize = keylen + alignmask;
buffer = kmalloc(absize, GFP_KERNEL);
if (!buffer)
return -ENOMEM;
alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
memcpy(alignbuffer, key, keylen);
ret = tfm->setkey(tfm, alignbuffer, keylen);
mm, treewide: rename kzfree() to kfree_sensitive() As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Joe Perches <joe@perches.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Jason A . Donenfeld" <Jason@zx2c4.com> Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 06:18:13 +00:00
kfree_sensitive(buffer);
return ret;
}
static int ahash_nosetkey(struct crypto_ahash *tfm, const u8 *key,
unsigned int keylen)
{
return -ENOSYS;
}
static void ahash_set_needkey(struct crypto_ahash *tfm)
{
const struct hash_alg_common *alg = crypto_hash_alg_common(tfm);
if (tfm->setkey != ahash_nosetkey &&
!(alg->base.cra_flags & CRYPTO_ALG_OPTIONAL_KEY))
crypto_ahash_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
}
int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
unsigned int keylen)
{
unsigned long alignmask = crypto_ahash_alignmask(tfm);
crypto: hash - prevent using keyed hashes without setting key Currently, almost none of the keyed hash algorithms check whether a key has been set before proceeding. Some algorithms are okay with this and will effectively just use a key of all 0's or some other bogus default. However, others will severely break, as demonstrated using "hmac(sha3-512-generic)", the unkeyed use of which causes a kernel crash via a (potentially exploitable) stack buffer overflow. A while ago, this problem was solved for AF_ALG by pairing each hash transform with a 'has_key' bool. However, there are still other places in the kernel where userspace can specify an arbitrary hash algorithm by name, and the kernel uses it as unkeyed hash without checking whether it is really unkeyed. Examples of this include: - KEYCTL_DH_COMPUTE, via the KDF extension - dm-verity - dm-crypt, via the ESSIV support - dm-integrity, via the "internal hash" mode with no key given - drbd (Distributed Replicated Block Device) This bug is especially bad for KEYCTL_DH_COMPUTE as that requires no privileges to call. Fix the bug for all users by adding a flag CRYPTO_TFM_NEED_KEY to the ->crt_flags of each hash transform that indicates whether the transform still needs to be keyed or not. Then, make the hash init, import, and digest functions return -ENOKEY if the key is still needed. The new flag also replaces the 'has_key' bool which algif_hash was previously using, thereby simplifying the algif_hash implementation. Reported-by: syzbot <syzkaller@googlegroups.com> Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-01-03 19:16:27 +00:00
int err;
if ((unsigned long)key & alignmask)
crypto: hash - prevent using keyed hashes without setting key Currently, almost none of the keyed hash algorithms check whether a key has been set before proceeding. Some algorithms are okay with this and will effectively just use a key of all 0's or some other bogus default. However, others will severely break, as demonstrated using "hmac(sha3-512-generic)", the unkeyed use of which causes a kernel crash via a (potentially exploitable) stack buffer overflow. A while ago, this problem was solved for AF_ALG by pairing each hash transform with a 'has_key' bool. However, there are still other places in the kernel where userspace can specify an arbitrary hash algorithm by name, and the kernel uses it as unkeyed hash without checking whether it is really unkeyed. Examples of this include: - KEYCTL_DH_COMPUTE, via the KDF extension - dm-verity - dm-crypt, via the ESSIV support - dm-integrity, via the "internal hash" mode with no key given - drbd (Distributed Replicated Block Device) This bug is especially bad for KEYCTL_DH_COMPUTE as that requires no privileges to call. Fix the bug for all users by adding a flag CRYPTO_TFM_NEED_KEY to the ->crt_flags of each hash transform that indicates whether the transform still needs to be keyed or not. Then, make the hash init, import, and digest functions return -ENOKEY if the key is still needed. The new flag also replaces the 'has_key' bool which algif_hash was previously using, thereby simplifying the algif_hash implementation. Reported-by: syzbot <syzkaller@googlegroups.com> Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-01-03 19:16:27 +00:00
err = ahash_setkey_unaligned(tfm, key, keylen);
else
err = tfm->setkey(tfm, key, keylen);
if (unlikely(err)) {
ahash_set_needkey(tfm);
crypto: hash - prevent using keyed hashes without setting key Currently, almost none of the keyed hash algorithms check whether a key has been set before proceeding. Some algorithms are okay with this and will effectively just use a key of all 0's or some other bogus default. However, others will severely break, as demonstrated using "hmac(sha3-512-generic)", the unkeyed use of which causes a kernel crash via a (potentially exploitable) stack buffer overflow. A while ago, this problem was solved for AF_ALG by pairing each hash transform with a 'has_key' bool. However, there are still other places in the kernel where userspace can specify an arbitrary hash algorithm by name, and the kernel uses it as unkeyed hash without checking whether it is really unkeyed. Examples of this include: - KEYCTL_DH_COMPUTE, via the KDF extension - dm-verity - dm-crypt, via the ESSIV support - dm-integrity, via the "internal hash" mode with no key given - drbd (Distributed Replicated Block Device) This bug is especially bad for KEYCTL_DH_COMPUTE as that requires no privileges to call. Fix the bug for all users by adding a flag CRYPTO_TFM_NEED_KEY to the ->crt_flags of each hash transform that indicates whether the transform still needs to be keyed or not. Then, make the hash init, import, and digest functions return -ENOKEY if the key is still needed. The new flag also replaces the 'has_key' bool which algif_hash was previously using, thereby simplifying the algif_hash implementation. Reported-by: syzbot <syzkaller@googlegroups.com> Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-01-03 19:16:27 +00:00
return err;
}
crypto: hash - prevent using keyed hashes without setting key Currently, almost none of the keyed hash algorithms check whether a key has been set before proceeding. Some algorithms are okay with this and will effectively just use a key of all 0's or some other bogus default. However, others will severely break, as demonstrated using "hmac(sha3-512-generic)", the unkeyed use of which causes a kernel crash via a (potentially exploitable) stack buffer overflow. A while ago, this problem was solved for AF_ALG by pairing each hash transform with a 'has_key' bool. However, there are still other places in the kernel where userspace can specify an arbitrary hash algorithm by name, and the kernel uses it as unkeyed hash without checking whether it is really unkeyed. Examples of this include: - KEYCTL_DH_COMPUTE, via the KDF extension - dm-verity - dm-crypt, via the ESSIV support - dm-integrity, via the "internal hash" mode with no key given - drbd (Distributed Replicated Block Device) This bug is especially bad for KEYCTL_DH_COMPUTE as that requires no privileges to call. Fix the bug for all users by adding a flag CRYPTO_TFM_NEED_KEY to the ->crt_flags of each hash transform that indicates whether the transform still needs to be keyed or not. Then, make the hash init, import, and digest functions return -ENOKEY if the key is still needed. The new flag also replaces the 'has_key' bool which algif_hash was previously using, thereby simplifying the algif_hash implementation. Reported-by: syzbot <syzkaller@googlegroups.com> Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-01-03 19:16:27 +00:00
crypto_ahash_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
return 0;
}
EXPORT_SYMBOL_GPL(crypto_ahash_setkey);
static int ahash_save_req(struct ahash_request *req, crypto_completion_t cplt,
bool has_state)
{
struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
unsigned long alignmask = crypto_ahash_alignmask(tfm);
unsigned int ds = crypto_ahash_digestsize(tfm);
struct ahash_request *subreq;
unsigned int subreq_size;
unsigned int reqsize;
u8 *result;
gfp_t gfp;
u32 flags;
subreq_size = sizeof(*subreq);
reqsize = crypto_ahash_reqsize(tfm);
reqsize = ALIGN(reqsize, crypto_tfm_ctx_alignment());
subreq_size += reqsize;
subreq_size += ds;
subreq_size += alignmask & ~(crypto_tfm_ctx_alignment() - 1);
flags = ahash_request_flags(req);
gfp = (flags & CRYPTO_TFM_REQ_MAY_SLEEP) ? GFP_KERNEL : GFP_ATOMIC;
subreq = kmalloc(subreq_size, gfp);
if (!subreq)
return -ENOMEM;
ahash_request_set_tfm(subreq, tfm);
ahash_request_set_callback(subreq, flags, cplt, req);
result = (u8 *)(subreq + 1) + reqsize;
result = PTR_ALIGN(result, alignmask + 1);
ahash_request_set_crypt(subreq, req->src, result, req->nbytes);
if (has_state) {
void *state;
state = kmalloc(crypto_ahash_statesize(tfm), gfp);
if (!state) {
kfree(subreq);
return -ENOMEM;
}
crypto_ahash_export(req, state);
crypto_ahash_import(subreq, state);
kfree_sensitive(state);
}
req->priv = subreq;
return 0;
}
static void ahash_restore_req(struct ahash_request *req, int err)
{
struct ahash_request *subreq = req->priv;
if (!err)
memcpy(req->result, subreq->result,
crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
req->priv = NULL;
kfree_sensitive(subreq);
}
static void ahash_op_unaligned_done(void *data, int err)
{
struct ahash_request *areq = data;
if (err == -EINPROGRESS)
goto out;
/* First copy req->result into req->priv.result */
ahash_restore_req(areq, err);
out:
/* Complete the ORIGINAL request. */
ahash_request_complete(areq, err);
}
static int ahash_op_unaligned(struct ahash_request *req,
int (*op)(struct ahash_request *),
bool has_state)
{
int err;
err = ahash_save_req(req, ahash_op_unaligned_done, has_state);
if (err)
return err;
err = op(req->priv);
if (err == -EINPROGRESS || err == -EBUSY)
return err;
ahash_restore_req(req, err);
return err;
}
static int crypto_ahash_op(struct ahash_request *req,
int (*op)(struct ahash_request *),
bool has_state)
{
struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
unsigned long alignmask = crypto_ahash_alignmask(tfm);
int err;
if ((unsigned long)req->result & alignmask)
err = ahash_op_unaligned(req, op, has_state);
else
err = op(req);
return crypto_hash_errstat(crypto_hash_alg_common(tfm), err);
}
int crypto_ahash_final(struct ahash_request *req)
{
struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
struct hash_alg_common *alg = crypto_hash_alg_common(tfm);
if (IS_ENABLED(CONFIG_CRYPTO_STATS))
atomic64_inc(&hash_get_stat(alg)->hash_cnt);
return crypto_ahash_op(req, tfm->final, true);
}
EXPORT_SYMBOL_GPL(crypto_ahash_final);
int crypto_ahash_finup(struct ahash_request *req)
{
struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
struct hash_alg_common *alg = crypto_hash_alg_common(tfm);
if (IS_ENABLED(CONFIG_CRYPTO_STATS)) {
struct crypto_istat_hash *istat = hash_get_stat(alg);
atomic64_inc(&istat->hash_cnt);
atomic64_add(req->nbytes, &istat->hash_tlen);
}
return crypto_ahash_op(req, tfm->finup, true);
}
EXPORT_SYMBOL_GPL(crypto_ahash_finup);
int crypto_ahash_digest(struct ahash_request *req)
{
crypto: hash - prevent using keyed hashes without setting key Currently, almost none of the keyed hash algorithms check whether a key has been set before proceeding. Some algorithms are okay with this and will effectively just use a key of all 0's or some other bogus default. However, others will severely break, as demonstrated using "hmac(sha3-512-generic)", the unkeyed use of which causes a kernel crash via a (potentially exploitable) stack buffer overflow. A while ago, this problem was solved for AF_ALG by pairing each hash transform with a 'has_key' bool. However, there are still other places in the kernel where userspace can specify an arbitrary hash algorithm by name, and the kernel uses it as unkeyed hash without checking whether it is really unkeyed. Examples of this include: - KEYCTL_DH_COMPUTE, via the KDF extension - dm-verity - dm-crypt, via the ESSIV support - dm-integrity, via the "internal hash" mode with no key given - drbd (Distributed Replicated Block Device) This bug is especially bad for KEYCTL_DH_COMPUTE as that requires no privileges to call. Fix the bug for all users by adding a flag CRYPTO_TFM_NEED_KEY to the ->crt_flags of each hash transform that indicates whether the transform still needs to be keyed or not. Then, make the hash init, import, and digest functions return -ENOKEY if the key is still needed. The new flag also replaces the 'has_key' bool which algif_hash was previously using, thereby simplifying the algif_hash implementation. Reported-by: syzbot <syzkaller@googlegroups.com> Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-01-03 19:16:27 +00:00
struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
struct hash_alg_common *alg = crypto_hash_alg_common(tfm);
if (IS_ENABLED(CONFIG_CRYPTO_STATS)) {
struct crypto_istat_hash *istat = hash_get_stat(alg);
atomic64_inc(&istat->hash_cnt);
atomic64_add(req->nbytes, &istat->hash_tlen);
}
crypto: hash - prevent using keyed hashes without setting key Currently, almost none of the keyed hash algorithms check whether a key has been set before proceeding. Some algorithms are okay with this and will effectively just use a key of all 0's or some other bogus default. However, others will severely break, as demonstrated using "hmac(sha3-512-generic)", the unkeyed use of which causes a kernel crash via a (potentially exploitable) stack buffer overflow. A while ago, this problem was solved for AF_ALG by pairing each hash transform with a 'has_key' bool. However, there are still other places in the kernel where userspace can specify an arbitrary hash algorithm by name, and the kernel uses it as unkeyed hash without checking whether it is really unkeyed. Examples of this include: - KEYCTL_DH_COMPUTE, via the KDF extension - dm-verity - dm-crypt, via the ESSIV support - dm-integrity, via the "internal hash" mode with no key given - drbd (Distributed Replicated Block Device) This bug is especially bad for KEYCTL_DH_COMPUTE as that requires no privileges to call. Fix the bug for all users by adding a flag CRYPTO_TFM_NEED_KEY to the ->crt_flags of each hash transform that indicates whether the transform still needs to be keyed or not. Then, make the hash init, import, and digest functions return -ENOKEY if the key is still needed. The new flag also replaces the 'has_key' bool which algif_hash was previously using, thereby simplifying the algif_hash implementation. Reported-by: syzbot <syzkaller@googlegroups.com> Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-01-03 19:16:27 +00:00
if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
return crypto_hash_errstat(alg, -ENOKEY);
return crypto_ahash_op(req, tfm->digest, false);
}
EXPORT_SYMBOL_GPL(crypto_ahash_digest);
static void ahash_def_finup_done2(void *data, int err)
{
struct ahash_request *areq = data;
if (err == -EINPROGRESS)
return;
ahash_restore_req(areq, err);
ahash_request_complete(areq, err);
}
static int ahash_def_finup_finish1(struct ahash_request *req, int err)
{
struct ahash_request *subreq = req->priv;
if (err)
goto out;
subreq->base.complete = ahash_def_finup_done2;
err = crypto_ahash_reqtfm(req)->final(subreq);
if (err == -EINPROGRESS || err == -EBUSY)
return err;
out:
ahash_restore_req(req, err);
return err;
}
static void ahash_def_finup_done1(void *data, int err)
{
struct ahash_request *areq = data;
struct ahash_request *subreq;
if (err == -EINPROGRESS)
goto out;
subreq = areq->priv;
subreq->base.flags &= CRYPTO_TFM_REQ_MAY_BACKLOG;
err = ahash_def_finup_finish1(areq, err);
if (err == -EINPROGRESS || err == -EBUSY)
return;
out:
ahash_request_complete(areq, err);
}
static int ahash_def_finup(struct ahash_request *req)
{
struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
crypto: hash - Simplify the ahash_finup implementation The ahash_def_finup() can make use of the request save/restore functions, thus make it so. This simplifies the code a little and unifies the code paths. Note that the same remark about free()ing the req->priv applies here, the req->priv can only be free()'d after the original request was restored. Finally, squash a bug in the invocation of completion in the ASYNC path. In both ahash_def_finup_done{1,2}, the function areq->base.complete(X, err); was called with X=areq->base.data . This is incorrect , as X=&areq->base is the correct value. By analysis of the data structures, we see the areq is of type 'struct ahash_request' , areq->base is of type 'struct crypto_async_request' and areq->base.completion is of type crypto_completion_t, which is defined in include/linux/crypto.h as: typedef void (*crypto_completion_t)(struct crypto_async_request *req, int err); This is one lead that the X should be &areq->base . Next up, we can inspect other code which calls the completion callback to give us kind-of statistical idea of how this callback is used. We can try: $ git grep base\.complete\( drivers/crypto/ Finally, by inspecting ahash_request_set_callback() implementation defined in include/crypto/hash.h , we observe that the .data entry of 'struct crypto_async_request' is intended for arbitrary data, not for completion argument. Signed-off-by: Marek Vasut <marex@denx.de> Cc: David S. Miller <davem@davemloft.net> Cc: Fabio Estevam <fabio.estevam@freescale.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Shawn Guo <shawn.guo@linaro.org> Cc: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-03-14 01:37:06 +00:00
int err;
err = ahash_save_req(req, ahash_def_finup_done1, true);
crypto: hash - Simplify the ahash_finup implementation The ahash_def_finup() can make use of the request save/restore functions, thus make it so. This simplifies the code a little and unifies the code paths. Note that the same remark about free()ing the req->priv applies here, the req->priv can only be free()'d after the original request was restored. Finally, squash a bug in the invocation of completion in the ASYNC path. In both ahash_def_finup_done{1,2}, the function areq->base.complete(X, err); was called with X=areq->base.data . This is incorrect , as X=&areq->base is the correct value. By analysis of the data structures, we see the areq is of type 'struct ahash_request' , areq->base is of type 'struct crypto_async_request' and areq->base.completion is of type crypto_completion_t, which is defined in include/linux/crypto.h as: typedef void (*crypto_completion_t)(struct crypto_async_request *req, int err); This is one lead that the X should be &areq->base . Next up, we can inspect other code which calls the completion callback to give us kind-of statistical idea of how this callback is used. We can try: $ git grep base\.complete\( drivers/crypto/ Finally, by inspecting ahash_request_set_callback() implementation defined in include/crypto/hash.h , we observe that the .data entry of 'struct crypto_async_request' is intended for arbitrary data, not for completion argument. Signed-off-by: Marek Vasut <marex@denx.de> Cc: David S. Miller <davem@davemloft.net> Cc: Fabio Estevam <fabio.estevam@freescale.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Shawn Guo <shawn.guo@linaro.org> Cc: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-03-14 01:37:06 +00:00
if (err)
return err;
err = tfm->update(req->priv);
if (err == -EINPROGRESS || err == -EBUSY)
return err;
crypto: hash - Simplify the ahash_finup implementation The ahash_def_finup() can make use of the request save/restore functions, thus make it so. This simplifies the code a little and unifies the code paths. Note that the same remark about free()ing the req->priv applies here, the req->priv can only be free()'d after the original request was restored. Finally, squash a bug in the invocation of completion in the ASYNC path. In both ahash_def_finup_done{1,2}, the function areq->base.complete(X, err); was called with X=areq->base.data . This is incorrect , as X=&areq->base is the correct value. By analysis of the data structures, we see the areq is of type 'struct ahash_request' , areq->base is of type 'struct crypto_async_request' and areq->base.completion is of type crypto_completion_t, which is defined in include/linux/crypto.h as: typedef void (*crypto_completion_t)(struct crypto_async_request *req, int err); This is one lead that the X should be &areq->base . Next up, we can inspect other code which calls the completion callback to give us kind-of statistical idea of how this callback is used. We can try: $ git grep base\.complete\( drivers/crypto/ Finally, by inspecting ahash_request_set_callback() implementation defined in include/crypto/hash.h , we observe that the .data entry of 'struct crypto_async_request' is intended for arbitrary data, not for completion argument. Signed-off-by: Marek Vasut <marex@denx.de> Cc: David S. Miller <davem@davemloft.net> Cc: Fabio Estevam <fabio.estevam@freescale.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Shawn Guo <shawn.guo@linaro.org> Cc: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-03-14 01:37:06 +00:00
return ahash_def_finup_finish1(req, err);
}
static void crypto_ahash_exit_tfm(struct crypto_tfm *tfm)
{
struct crypto_ahash *hash = __crypto_ahash_cast(tfm);
struct ahash_alg *alg = crypto_ahash_alg(hash);
alg->exit_tfm(hash);
}
static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
{
struct crypto_ahash *hash = __crypto_ahash_cast(tfm);
struct ahash_alg *alg = crypto_ahash_alg(hash);
hash->setkey = ahash_nosetkey;
crypto_ahash_set_statesize(hash, alg->halg.statesize);
if (tfm->__crt_alg->cra_type != &crypto_ahash_type)
return crypto_init_shash_ops_async(tfm);
hash->init = alg->init;
hash->update = alg->update;
hash->final = alg->final;
hash->finup = alg->finup ?: ahash_def_finup;
hash->digest = alg->digest;
hash->export = alg->export;
hash->import = alg->import;
if (alg->setkey) {
hash->setkey = alg->setkey;
ahash_set_needkey(hash);
}
if (alg->exit_tfm)
tfm->exit = crypto_ahash_exit_tfm;
return alg->init_tfm ? alg->init_tfm(hash) : 0;
}
static unsigned int crypto_ahash_extsize(struct crypto_alg *alg)
{
if (alg->cra_type != &crypto_ahash_type)
return sizeof(struct crypto_shash *);
return crypto_alg_extsize(alg);
}
static void crypto_ahash_free_instance(struct crypto_instance *inst)
{
struct ahash_instance *ahash = ahash_instance(inst);
ahash->free(ahash);
}
static int __maybe_unused crypto_ahash_report(
struct sk_buff *skb, struct crypto_alg *alg)
{
struct crypto_report_hash rhash;
crypto: user - clean up report structure copying There have been a pretty ridiculous number of issues with initializing the report structures that are copied to userspace by NETLINK_CRYPTO. Commit 4473710df1f8 ("crypto: user - Prepare for CRYPTO_MAX_ALG_NAME expansion") replaced some strncpy()s with strlcpy()s, thereby introducing information leaks. Later two other people tried to replace other strncpy()s with strlcpy() too, which would have introduced even more information leaks: - https://lore.kernel.org/patchwork/patch/954991/ - https://patchwork.kernel.org/patch/10434351/ Commit cac5818c25d0 ("crypto: user - Implement a generic crypto statistics") also uses the buggy strlcpy() approach and therefore leaks uninitialized memory to userspace. A fix was proposed, but it was originally incomplete. Seeing as how apparently no one can get this right with the current approach, change all the reporting functions to: - Start by memsetting the report structure to 0. This guarantees it's always initialized, regardless of what happens later. - Initialize all strings using strscpy(). This is safe after the memset, ensures null termination of long strings, avoids unnecessary work, and avoids the -Wstringop-truncation warnings from gcc. - Use sizeof(var) instead of sizeof(type). This is more robust against copy+paste errors. For simplicity, also reuse the -EMSGSIZE return value from nla_put(). Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-03 21:56:03 +00:00
memset(&rhash, 0, sizeof(rhash));
strscpy(rhash.type, "ahash", sizeof(rhash.type));
rhash.blocksize = alg->cra_blocksize;
rhash.digestsize = __crypto_hash_alg_common(alg)->digestsize;
crypto: user - clean up report structure copying There have been a pretty ridiculous number of issues with initializing the report structures that are copied to userspace by NETLINK_CRYPTO. Commit 4473710df1f8 ("crypto: user - Prepare for CRYPTO_MAX_ALG_NAME expansion") replaced some strncpy()s with strlcpy()s, thereby introducing information leaks. Later two other people tried to replace other strncpy()s with strlcpy() too, which would have introduced even more information leaks: - https://lore.kernel.org/patchwork/patch/954991/ - https://patchwork.kernel.org/patch/10434351/ Commit cac5818c25d0 ("crypto: user - Implement a generic crypto statistics") also uses the buggy strlcpy() approach and therefore leaks uninitialized memory to userspace. A fix was proposed, but it was originally incomplete. Seeing as how apparently no one can get this right with the current approach, change all the reporting functions to: - Start by memsetting the report structure to 0. This guarantees it's always initialized, regardless of what happens later. - Initialize all strings using strscpy(). This is safe after the memset, ensures null termination of long strings, avoids unnecessary work, and avoids the -Wstringop-truncation warnings from gcc. - Use sizeof(var) instead of sizeof(type). This is more robust against copy+paste errors. For simplicity, also reuse the -EMSGSIZE return value from nla_put(). Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-03 21:56:03 +00:00
return nla_put(skb, CRYPTOCFGA_REPORT_HASH, sizeof(rhash), &rhash);
}
static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
__maybe_unused;
static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
{
seq_printf(m, "type : ahash\n");
seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
"yes" : "no");
seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
seq_printf(m, "digestsize : %u\n",
__crypto_hash_alg_common(alg)->digestsize);
}
static int __maybe_unused crypto_ahash_report_stat(
struct sk_buff *skb, struct crypto_alg *alg)
{
return crypto_hash_report_stat(skb, alg, "ahash");
}
static const struct crypto_type crypto_ahash_type = {
.extsize = crypto_ahash_extsize,
.init_tfm = crypto_ahash_init_tfm,
.free = crypto_ahash_free_instance,
#ifdef CONFIG_PROC_FS
.show = crypto_ahash_show,
#endif
#if IS_ENABLED(CONFIG_CRYPTO_USER)
.report = crypto_ahash_report,
#endif
#ifdef CONFIG_CRYPTO_STATS
.report_stat = crypto_ahash_report_stat,
#endif
.maskclear = ~CRYPTO_ALG_TYPE_MASK,
.maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
.type = CRYPTO_ALG_TYPE_AHASH,
.tfmsize = offsetof(struct crypto_ahash, base),
};
int crypto_grab_ahash(struct crypto_ahash_spawn *spawn,
struct crypto_instance *inst,
const char *name, u32 type, u32 mask)
{
spawn->base.frontend = &crypto_ahash_type;
return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
}
EXPORT_SYMBOL_GPL(crypto_grab_ahash);
struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type,
u32 mask)
{
return crypto_alloc_tfm(alg_name, &crypto_ahash_type, type, mask);
}
EXPORT_SYMBOL_GPL(crypto_alloc_ahash);
int crypto_has_ahash(const char *alg_name, u32 type, u32 mask)
{
return crypto_type_has_alg(alg_name, &crypto_ahash_type, type, mask);
}
EXPORT_SYMBOL_GPL(crypto_has_ahash);
struct crypto_ahash *crypto_clone_ahash(struct crypto_ahash *hash)
{
struct hash_alg_common *halg = crypto_hash_alg_common(hash);
struct crypto_tfm *tfm = crypto_ahash_tfm(hash);
struct crypto_ahash *nhash;
struct ahash_alg *alg;
int err;
if (!crypto_hash_alg_has_setkey(halg)) {
tfm = crypto_tfm_get(tfm);
if (IS_ERR(tfm))
return ERR_CAST(tfm);
return hash;
}
nhash = crypto_clone_tfm(&crypto_ahash_type, tfm);
if (IS_ERR(nhash))
return nhash;
nhash->init = hash->init;
nhash->update = hash->update;
nhash->final = hash->final;
nhash->finup = hash->finup;
nhash->digest = hash->digest;
nhash->export = hash->export;
nhash->import = hash->import;
nhash->setkey = hash->setkey;
nhash->reqsize = hash->reqsize;
nhash->statesize = hash->statesize;
if (tfm->__crt_alg->cra_type != &crypto_ahash_type)
return crypto_clone_shash_ops_async(nhash, hash);
err = -ENOSYS;
alg = crypto_ahash_alg(hash);
if (!alg->clone_tfm)
goto out_free_nhash;
err = alg->clone_tfm(nhash, hash);
if (err)
goto out_free_nhash;
return nhash;
out_free_nhash:
crypto_free_ahash(nhash);
return ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(crypto_clone_ahash);
static int ahash_prepare_alg(struct ahash_alg *alg)
{
struct crypto_alg *base = &alg->halg.base;
int err;
if (alg->halg.statesize == 0)
return -EINVAL;
err = hash_prepare_alg(&alg->halg);
if (err)
return err;
base->cra_type = &crypto_ahash_type;
base->cra_flags |= CRYPTO_ALG_TYPE_AHASH;
return 0;
}
int crypto_register_ahash(struct ahash_alg *alg)
{
struct crypto_alg *base = &alg->halg.base;
int err;
err = ahash_prepare_alg(alg);
if (err)
return err;
return crypto_register_alg(base);
}
EXPORT_SYMBOL_GPL(crypto_register_ahash);
void crypto_unregister_ahash(struct ahash_alg *alg)
{
crypto_unregister_alg(&alg->halg.base);
}
EXPORT_SYMBOL_GPL(crypto_unregister_ahash);
int crypto_register_ahashes(struct ahash_alg *algs, int count)
{
int i, ret;
for (i = 0; i < count; i++) {
ret = crypto_register_ahash(&algs[i]);
if (ret)
goto err;
}
return 0;
err:
for (--i; i >= 0; --i)
crypto_unregister_ahash(&algs[i]);
return ret;
}
EXPORT_SYMBOL_GPL(crypto_register_ahashes);
void crypto_unregister_ahashes(struct ahash_alg *algs, int count)
{
int i;
for (i = count - 1; i >= 0; --i)
crypto_unregister_ahash(&algs[i]);
}
EXPORT_SYMBOL_GPL(crypto_unregister_ahashes);
int ahash_register_instance(struct crypto_template *tmpl,
struct ahash_instance *inst)
{
int err;
if (WARN_ON(!inst->free))
return -EINVAL;
err = ahash_prepare_alg(&inst->alg);
if (err)
return err;
return crypto_register_instance(tmpl, ahash_crypto_instance(inst));
}
EXPORT_SYMBOL_GPL(ahash_register_instance);
bool crypto_hash_alg_has_setkey(struct hash_alg_common *halg)
{
struct crypto_alg *alg = &halg->base;
if (alg->cra_type != &crypto_ahash_type)
return crypto_shash_alg_has_setkey(__crypto_shash_alg(alg));
return __crypto_ahash_alg(alg)->setkey != NULL;
}
EXPORT_SYMBOL_GPL(crypto_hash_alg_has_setkey);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Asynchronous cryptographic hash type");