From 05b3bbb53a0570c04aba24e5849a3715e1ed4583 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Thu, 2 Jan 2020 19:58:58 -0800 Subject: [PATCH] crypto: ccm - use crypto_grab_ahash() and simplify error paths Make the ccm and ccm_base templates use the new function crypto_grab_ahash() to initialize their ahash spawn. This is needed to make all spawns be initialized in a consistent way. Also simplify the error handling by taking advantage of crypto_drop_*() now accepting (as a no-op) spawns that haven't been initialized yet. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu --- crypto/ccm.c | 63 ++++++++++++++++++---------------------------------- 1 file changed, 21 insertions(+), 42 deletions(-) diff --git a/crypto/ccm.c b/crypto/ccm.c index 48766e81b933..a9fb46f22eaa 100644 --- a/crypto/ccm.c +++ b/crypto/ccm.c @@ -15,8 +15,6 @@ #include #include -#include "internal.h" - struct ccm_instance_ctx { struct crypto_skcipher_spawn ctr; struct crypto_ahash_spawn mac; @@ -452,10 +450,9 @@ static int crypto_ccm_create_common(struct crypto_template *tmpl, struct crypto_attr_type *algt; u32 mask; struct aead_instance *inst; - struct skcipher_alg *ctr; - struct crypto_alg *mac_alg; - struct hash_alg_common *mac; struct ccm_instance_ctx *ictx; + struct skcipher_alg *ctr; + struct hash_alg_common *mac; int err; algt = crypto_get_attr_type(tb); @@ -467,35 +464,26 @@ static int crypto_ccm_create_common(struct crypto_template *tmpl, mask = crypto_requires_sync(algt->type, algt->mask); - mac_alg = crypto_find_alg(mac_name, &crypto_ahash_type, - CRYPTO_ALG_TYPE_HASH, - CRYPTO_ALG_TYPE_AHASH_MASK | - CRYPTO_ALG_ASYNC); - if (IS_ERR(mac_alg)) - return PTR_ERR(mac_alg); + inst = kzalloc(sizeof(*inst) + sizeof(*ictx), GFP_KERNEL); + if (!inst) + return -ENOMEM; + ictx = aead_instance_ctx(inst); + + err = crypto_grab_ahash(&ictx->mac, aead_crypto_instance(inst), + mac_name, 0, CRYPTO_ALG_ASYNC); + if (err) + goto err_free_inst; + mac = crypto_spawn_ahash_alg(&ictx->mac); - mac = __crypto_hash_alg_common(mac_alg); err = -EINVAL; if (strncmp(mac->base.cra_name, "cbcmac(", 7) != 0 || mac->digestsize != 16) - goto out_put_mac; - - inst = kzalloc(sizeof(*inst) + sizeof(*ictx), GFP_KERNEL); - err = -ENOMEM; - if (!inst) - goto out_put_mac; - - ictx = aead_instance_ctx(inst); - err = crypto_init_ahash_spawn(&ictx->mac, mac, - aead_crypto_instance(inst)); - if (err) goto err_free_inst; err = crypto_grab_skcipher(&ictx->ctr, aead_crypto_instance(inst), ctr_name, 0, mask); if (err) - goto err_drop_mac; - + goto err_free_inst; ctr = crypto_spawn_skcipher_alg(&ictx->ctr); /* The skcipher algorithm must be CTR mode, using 16-byte blocks. */ @@ -503,21 +491,21 @@ static int crypto_ccm_create_common(struct crypto_template *tmpl, if (strncmp(ctr->base.cra_name, "ctr(", 4) != 0 || crypto_skcipher_alg_ivsize(ctr) != 16 || ctr->base.cra_blocksize != 1) - goto err_drop_ctr; + goto err_free_inst; /* ctr and cbcmac must use the same underlying block cipher. */ if (strcmp(ctr->base.cra_name + 4, mac->base.cra_name + 7) != 0) - goto err_drop_ctr; + goto err_free_inst; err = -ENAMETOOLONG; if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, "ccm(%s", ctr->base.cra_name + 4) >= CRYPTO_MAX_ALG_NAME) - goto err_drop_ctr; + goto err_free_inst; if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "ccm_base(%s,%s)", ctr->base.cra_driver_name, mac->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME) - goto err_drop_ctr; + goto err_free_inst; inst->alg.base.cra_flags = ctr->base.cra_flags & CRYPTO_ALG_ASYNC; inst->alg.base.cra_priority = (mac->base.cra_priority + @@ -539,20 +527,11 @@ static int crypto_ccm_create_common(struct crypto_template *tmpl, inst->free = crypto_ccm_free; err = aead_register_instance(tmpl, inst); - if (err) - goto err_drop_ctr; - -out_put_mac: - crypto_mod_put(mac_alg); - return err; - -err_drop_ctr: - crypto_drop_skcipher(&ictx->ctr); -err_drop_mac: - crypto_drop_ahash(&ictx->mac); + if (err) { err_free_inst: - kfree(inst); - goto out_put_mac; + crypto_ccm_free(inst); + } + return err; } static int crypto_ccm_create(struct crypto_template *tmpl, struct rtattr **tb)