From c4741b23059794bd99beef0f700103b0d983b3fd Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Thu, 11 Apr 2019 21:57:42 -0700 Subject: crypto: run initcalls for generic implementations earlier Use subsys_initcall for registration of all templates and generic algorithm implementations, rather than module_init. Then change cryptomgr to use arch_initcall, to place it before the subsys_initcalls. This is needed so that when both a generic and optimized implementation of an algorithm are built into the kernel (not loadable modules), the generic implementation is registered before the optimized one. Otherwise, the self-tests for the optimized implementation are unable to allocate the generic implementation for the new comparison fuzz tests. Note that on arm, a side effect of this change is that self-tests for generic implementations may run before the unaligned access handler has been installed. So, unaligned accesses will crash the kernel. This is arguably a good thing as it makes it easier to detect that type of bug. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu --- crypto/gcm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'crypto/gcm.c') diff --git a/crypto/gcm.c b/crypto/gcm.c index e1a11f529d25..ff498411b43f 100644 --- a/crypto/gcm.c +++ b/crypto/gcm.c @@ -1258,7 +1258,7 @@ static void __exit crypto_gcm_module_exit(void) ARRAY_SIZE(crypto_gcm_tmpls)); } -module_init(crypto_gcm_module_init); +subsys_initcall(crypto_gcm_module_init); module_exit(crypto_gcm_module_exit); MODULE_LICENSE("GPL"); -- cgit From f699594d436960160f6d5ba84ed4a222f20d11cd Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Thu, 18 Apr 2019 14:43:02 -0700 Subject: crypto: gcm - fix incompatibility between "gcm" and "gcm_base" GCM instances can be created by either the "gcm" template, which only allows choosing the block cipher, e.g. "gcm(aes)"; or by "gcm_base", which allows choosing the ctr and ghash implementations, e.g. "gcm_base(ctr(aes-generic),ghash-generic)". However, a "gcm_base" instance prevents a "gcm" instance from being registered using the same implementations. Nor will the instance be found by lookups of "gcm". This can be used as a denial of service. Moreover, "gcm_base" instances are never tested by the crypto self-tests, even if there are compatible "gcm" tests. The root cause of these problems is that instances of the two templates use different cra_names. Therefore, fix these problems by making "gcm_base" instances set the same cra_name as "gcm" instances, e.g. "gcm(aes)" instead of "gcm_base(ctr(aes-generic),ghash-generic)". This requires extracting the block cipher name from the name of the ctr algorithm. It also requires starting to verify that the algorithms are really ctr and ghash, not something else entirely. But it would be bizarre if anyone were actually using non-gcm-compatible algorithms with gcm_base, so this shouldn't break anyone in practice. Fixes: d00aa19b507b ("[CRYPTO] gcm: Allow block cipher parameter") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu --- crypto/gcm.c | 34 +++++++++++----------------------- 1 file changed, 11 insertions(+), 23 deletions(-) (limited to 'crypto/gcm.c') diff --git a/crypto/gcm.c b/crypto/gcm.c index ff498411b43f..33f45a980967 100644 --- a/crypto/gcm.c +++ b/crypto/gcm.c @@ -597,7 +597,6 @@ static void crypto_gcm_free(struct aead_instance *inst) static int crypto_gcm_create_common(struct crypto_template *tmpl, struct rtattr **tb, - const char *full_name, const char *ctr_name, const char *ghash_name) { @@ -638,7 +637,8 @@ static int crypto_gcm_create_common(struct crypto_template *tmpl, goto err_free_inst; err = -EINVAL; - if (ghash->digestsize != 16) + if (strcmp(ghash->base.cra_name, "ghash") != 0 || + ghash->digestsize != 16) goto err_drop_ghash; crypto_set_skcipher_spawn(&ctx->ctr, aead_crypto_instance(inst)); @@ -650,24 +650,24 @@ static int crypto_gcm_create_common(struct crypto_template *tmpl, ctr = crypto_spawn_skcipher_alg(&ctx->ctr); - /* We only support 16-byte blocks. */ + /* The skcipher algorithm must be CTR mode, using 16-byte blocks. */ err = -EINVAL; - if (crypto_skcipher_alg_ivsize(ctr) != 16) + if (strncmp(ctr->base.cra_name, "ctr(", 4) != 0 || + crypto_skcipher_alg_ivsize(ctr) != 16 || + ctr->base.cra_blocksize != 1) goto out_put_ctr; - /* Not a stream cipher? */ - if (ctr->base.cra_blocksize != 1) + err = -ENAMETOOLONG; + if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, + "gcm(%s", ctr->base.cra_name + 4) >= CRYPTO_MAX_ALG_NAME) goto out_put_ctr; - err = -ENAMETOOLONG; if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "gcm_base(%s,%s)", ctr->base.cra_driver_name, ghash_alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME) goto out_put_ctr; - memcpy(inst->alg.base.cra_name, full_name, CRYPTO_MAX_ALG_NAME); - inst->alg.base.cra_flags = (ghash->base.cra_flags | ctr->base.cra_flags) & CRYPTO_ALG_ASYNC; inst->alg.base.cra_priority = (ghash->base.cra_priority + @@ -709,7 +709,6 @@ static int crypto_gcm_create(struct crypto_template *tmpl, struct rtattr **tb) { const char *cipher_name; char ctr_name[CRYPTO_MAX_ALG_NAME]; - char full_name[CRYPTO_MAX_ALG_NAME]; cipher_name = crypto_attr_alg_name(tb[1]); if (IS_ERR(cipher_name)) @@ -719,12 +718,7 @@ static int crypto_gcm_create(struct crypto_template *tmpl, struct rtattr **tb) CRYPTO_MAX_ALG_NAME) return -ENAMETOOLONG; - if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm(%s)", cipher_name) >= - CRYPTO_MAX_ALG_NAME) - return -ENAMETOOLONG; - - return crypto_gcm_create_common(tmpl, tb, full_name, - ctr_name, "ghash"); + return crypto_gcm_create_common(tmpl, tb, ctr_name, "ghash"); } static int crypto_gcm_base_create(struct crypto_template *tmpl, @@ -732,7 +726,6 @@ static int crypto_gcm_base_create(struct crypto_template *tmpl, { const char *ctr_name; const char *ghash_name; - char full_name[CRYPTO_MAX_ALG_NAME]; ctr_name = crypto_attr_alg_name(tb[1]); if (IS_ERR(ctr_name)) @@ -742,12 +735,7 @@ static int crypto_gcm_base_create(struct crypto_template *tmpl, if (IS_ERR(ghash_name)) return PTR_ERR(ghash_name); - if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm_base(%s,%s)", - ctr_name, ghash_name) >= CRYPTO_MAX_ALG_NAME) - return -ENAMETOOLONG; - - return crypto_gcm_create_common(tmpl, tb, full_name, - ctr_name, ghash_name); + return crypto_gcm_create_common(tmpl, tb, ctr_name, ghash_name); } static int crypto_rfc4106_setkey(struct crypto_aead *parent, const u8 *key, -- cgit