OpenCloudOS-Kernel/include/crypto/internal/hash.h

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/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Hash algorithms.
*
* Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
*/
#ifndef _CRYPTO_INTERNAL_HASH_H
#define _CRYPTO_INTERNAL_HASH_H
#include <crypto/algapi.h>
#include <crypto/hash.h>
struct ahash_request;
struct scatterlist;
struct crypto_hash_walk {
char *data;
unsigned int offset;
unsigned int alignmask;
struct page *pg;
unsigned int entrylen;
unsigned int total;
struct scatterlist *sg;
unsigned int flags;
};
struct ahash_instance {
void (*free)(struct ahash_instance *inst);
union {
struct {
char head[offsetof(struct ahash_alg, halg.base)];
struct crypto_instance base;
} s;
struct ahash_alg alg;
};
};
struct shash_instance {
void (*free)(struct shash_instance *inst);
union {
struct {
char head[offsetof(struct shash_alg, base)];
struct crypto_instance base;
} s;
struct shash_alg alg;
};
};
struct crypto_ahash_spawn {
struct crypto_spawn base;
};
struct crypto_shash_spawn {
struct crypto_spawn base;
};
int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err);
int crypto_hash_walk_first(struct ahash_request *req,
struct crypto_hash_walk *walk);
static inline int crypto_hash_walk_last(struct crypto_hash_walk *walk)
{
return !(walk->entrylen | walk->total);
}
int crypto_register_ahash(struct ahash_alg *alg);
void crypto_unregister_ahash(struct ahash_alg *alg);
int crypto_register_ahashes(struct ahash_alg *algs, int count);
void crypto_unregister_ahashes(struct ahash_alg *algs, int count);
int ahash_register_instance(struct crypto_template *tmpl,
struct ahash_instance *inst);
bool crypto_shash_alg_has_setkey(struct shash_alg *alg);
crypto: hmac - require that the underlying hash algorithm is unkeyed Because the HMAC template didn't check that its underlying hash algorithm is unkeyed, trying to use "hmac(hmac(sha3-512-generic))" through AF_ALG or through KEYCTL_DH_COMPUTE resulted in the inner HMAC being used without having been keyed, resulting in sha3_update() being called without sha3_init(), causing a stack buffer overflow. This is a very old bug, but it seems to have only started causing real problems when SHA-3 support was added (requires CONFIG_CRYPTO_SHA3) because the innermost hash's state is ->import()ed from a zeroed buffer, and it just so happens that other hash algorithms are fine with that, but SHA-3 is not. However, there could be arch or hardware-dependent hash algorithms also affected; I couldn't test everything. Fix the bug by introducing a function crypto_shash_alg_has_setkey() which tests whether a shash algorithm is keyed. Then update the HMAC template to require that its underlying hash algorithm is unkeyed. Here is a reproducer: #include <linux/if_alg.h> #include <sys/socket.h> int main() { int algfd; struct sockaddr_alg addr = { .salg_type = "hash", .salg_name = "hmac(hmac(sha3-512-generic))", }; char key[4096] = { 0 }; algfd = socket(AF_ALG, SOCK_SEQPACKET, 0); bind(algfd, (const struct sockaddr *)&addr, sizeof(addr)); setsockopt(algfd, SOL_ALG, ALG_SET_KEY, key, sizeof(key)); } Here was the KASAN report from syzbot: BUG: KASAN: stack-out-of-bounds in memcpy include/linux/string.h:341 [inline] BUG: KASAN: stack-out-of-bounds in sha3_update+0xdf/0x2e0 crypto/sha3_generic.c:161 Write of size 4096 at addr ffff8801cca07c40 by task syzkaller076574/3044 CPU: 1 PID: 3044 Comm: syzkaller076574 Not tainted 4.14.0-mm1+ #25 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x25b/0x340 mm/kasan/report.c:409 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x137/0x190 mm/kasan/kasan.c:267 memcpy+0x37/0x50 mm/kasan/kasan.c:303 memcpy include/linux/string.h:341 [inline] sha3_update+0xdf/0x2e0 crypto/sha3_generic.c:161 crypto_shash_update+0xcb/0x220 crypto/shash.c:109 shash_finup_unaligned+0x2a/0x60 crypto/shash.c:151 crypto_shash_finup+0xc4/0x120 crypto/shash.c:165 hmac_finup+0x182/0x330 crypto/hmac.c:152 crypto_shash_finup+0xc4/0x120 crypto/shash.c:165 shash_digest_unaligned+0x9e/0xd0 crypto/shash.c:172 crypto_shash_digest+0xc4/0x120 crypto/shash.c:186 hmac_setkey+0x36a/0x690 crypto/hmac.c:66 crypto_shash_setkey+0xad/0x190 crypto/shash.c:64 shash_async_setkey+0x47/0x60 crypto/shash.c:207 crypto_ahash_setkey+0xaf/0x180 crypto/ahash.c:200 hash_setkey+0x40/0x90 crypto/algif_hash.c:446 alg_setkey crypto/af_alg.c:221 [inline] alg_setsockopt+0x2a1/0x350 crypto/af_alg.c:254 SYSC_setsockopt net/socket.c:1851 [inline] SyS_setsockopt+0x189/0x360 net/socket.c:1830 entry_SYSCALL_64_fastpath+0x1f/0x96 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>
2017-11-29 10:01:38 +08:00
static inline bool crypto_shash_alg_needs_key(struct shash_alg *alg)
{
return crypto_shash_alg_has_setkey(alg) &&
!(alg->base.cra_flags & CRYPTO_ALG_OPTIONAL_KEY);
}
bool crypto_hash_alg_has_setkey(struct hash_alg_common *halg);
int crypto_grab_ahash(struct crypto_ahash_spawn *spawn,
struct crypto_instance *inst,
const char *name, u32 type, u32 mask);
static inline void crypto_drop_ahash(struct crypto_ahash_spawn *spawn)
{
crypto_drop_spawn(&spawn->base);
}
static inline struct hash_alg_common *crypto_spawn_ahash_alg(
struct crypto_ahash_spawn *spawn)
{
return __crypto_hash_alg_common(spawn->base.alg);
}
int crypto_register_shash(struct shash_alg *alg);
void crypto_unregister_shash(struct shash_alg *alg);
int crypto_register_shashes(struct shash_alg *algs, int count);
void crypto_unregister_shashes(struct shash_alg *algs, int count);
int shash_register_instance(struct crypto_template *tmpl,
struct shash_instance *inst);
void shash_free_singlespawn_instance(struct shash_instance *inst);
int crypto_grab_shash(struct crypto_shash_spawn *spawn,
struct crypto_instance *inst,
const char *name, u32 type, u32 mask);
static inline void crypto_drop_shash(struct crypto_shash_spawn *spawn)
{
crypto_drop_spawn(&spawn->base);
}
static inline struct shash_alg *crypto_spawn_shash_alg(
struct crypto_shash_spawn *spawn)
{
return __crypto_shash_alg(spawn->base.alg);
}
int shash_ahash_update(struct ahash_request *req, struct shash_desc *desc);
int shash_ahash_finup(struct ahash_request *req, struct shash_desc *desc);
int shash_ahash_digest(struct ahash_request *req, struct shash_desc *desc);
int crypto_init_shash_ops_async(struct crypto_tfm *tfm);
static inline void *crypto_ahash_ctx(struct crypto_ahash *tfm)
{
return crypto_tfm_ctx(crypto_ahash_tfm(tfm));
}
static inline struct ahash_alg *__crypto_ahash_alg(struct crypto_alg *alg)
{
return container_of(__crypto_hash_alg_common(alg), struct ahash_alg,
halg);
}
static inline void crypto_ahash_set_reqsize(struct crypto_ahash *tfm,
unsigned int reqsize)
{
tfm->reqsize = reqsize;
}
static inline struct crypto_instance *ahash_crypto_instance(
struct ahash_instance *inst)
{
return &inst->s.base;
}
static inline struct ahash_instance *ahash_instance(
struct crypto_instance *inst)
{
return container_of(inst, struct ahash_instance, s.base);
}
static inline struct ahash_instance *ahash_alg_instance(
struct crypto_ahash *ahash)
{
return ahash_instance(crypto_tfm_alg_instance(&ahash->base));
}
static inline void *ahash_instance_ctx(struct ahash_instance *inst)
{
return crypto_instance_ctx(ahash_crypto_instance(inst));
}
static inline void ahash_request_complete(struct ahash_request *req, int err)
{
req->base.complete(&req->base, err);
}
static inline u32 ahash_request_flags(struct ahash_request *req)
{
return req->base.flags;
}
static inline struct crypto_ahash *crypto_spawn_ahash(
struct crypto_ahash_spawn *spawn)
{
return crypto_spawn_tfm2(&spawn->base);
}
static inline int ahash_enqueue_request(struct crypto_queue *queue,
struct ahash_request *request)
{
return crypto_enqueue_request(queue, &request->base);
}
static inline struct ahash_request *ahash_dequeue_request(
struct crypto_queue *queue)
{
return ahash_request_cast(crypto_dequeue_request(queue));
}
static inline void *crypto_shash_ctx(struct crypto_shash *tfm)
{
return crypto_tfm_ctx(&tfm->base);
}
static inline struct crypto_instance *shash_crypto_instance(
struct shash_instance *inst)
{
return &inst->s.base;
}
static inline struct shash_instance *shash_instance(
struct crypto_instance *inst)
{
return container_of(inst, struct shash_instance, s.base);
}
static inline struct shash_instance *shash_alg_instance(
struct crypto_shash *shash)
{
return shash_instance(crypto_tfm_alg_instance(&shash->base));
}
static inline void *shash_instance_ctx(struct shash_instance *inst)
{
return crypto_instance_ctx(shash_crypto_instance(inst));
}
static inline struct crypto_shash *crypto_spawn_shash(
struct crypto_shash_spawn *spawn)
{
return crypto_spawn_tfm2(&spawn->base);
}
static inline void *crypto_shash_ctx_aligned(struct crypto_shash *tfm)
{
return crypto_tfm_ctx_aligned(&tfm->base);
}
static inline struct crypto_shash *__crypto_shash_cast(struct crypto_tfm *tfm)
{
return container_of(tfm, struct crypto_shash, base);
}
#endif /* _CRYPTO_INTERNAL_HASH_H */