From 723326b927b675daf4223fe31d7428eca68f194b Mon Sep 17 00:00:00 2001 From: Dmitry Kasatkin Date: Thu, 4 Jul 2013 17:40:01 +0300 Subject: [PATCH] ima: provide dedicated hash algo allocation function This patch provides dedicated hash algo allocation and deallocation function which can be used by different clients. Signed-off-by: Dmitry Kasatkin Signed-off-by: Mimi Zohar --- security/integrity/ima/ima_crypto.c | 43 +++++++++++++++++++---------- 1 file changed, 29 insertions(+), 14 deletions(-) diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c index 872c6698067c..e5d3ebf18436 100644 --- a/security/integrity/ima/ima_crypto.c +++ b/security/integrity/ima/ima_crypto.c @@ -39,6 +39,28 @@ int ima_init_crypto(void) return 0; } +static struct crypto_shash *ima_alloc_tfm(enum hash_algo algo) +{ + struct crypto_shash *tfm = ima_shash_tfm; + int rc; + + if (algo != ima_hash_algo && algo < HASH_ALGO__LAST) { + tfm = crypto_alloc_shash(hash_algo_name[algo], 0, 0); + if (IS_ERR(tfm)) { + rc = PTR_ERR(tfm); + pr_err("Can not allocate %s (reason: %d)\n", + hash_algo_name[algo], rc); + } + } + return tfm; +} + +static void ima_free_tfm(struct crypto_shash *tfm) +{ + if (tfm != ima_shash_tfm) + crypto_free_shash(tfm); +} + /* * Calculate the MD5/SHA1 file digest */ @@ -57,6 +79,8 @@ static int ima_calc_file_hash_tfm(struct file *file, desc.shash.tfm = tfm; desc.shash.flags = 0; + hash->length = crypto_shash_digestsize(tfm); + rc = crypto_shash_init(&desc.shash); if (rc != 0) return rc; @@ -98,25 +122,16 @@ out: int ima_calc_file_hash(struct file *file, struct ima_digest_data *hash) { - struct crypto_shash *tfm = ima_shash_tfm; + struct crypto_shash *tfm; int rc; - if (hash->algo != ima_hash_algo && hash->algo < HASH_ALGO__LAST) { - tfm = crypto_alloc_shash(hash_algo_name[hash->algo], 0, 0); - if (IS_ERR(tfm)) { - rc = PTR_ERR(tfm); - pr_err("Can not allocate %s (reason: %d)\n", - hash_algo_name[hash->algo], rc); - return rc; - } - } - - hash->length = crypto_shash_digestsize(tfm); + tfm = ima_alloc_tfm(hash->algo); + if (IS_ERR(tfm)) + return PTR_ERR(tfm); rc = ima_calc_file_hash_tfm(file, hash, tfm); - if (tfm != ima_shash_tfm) - crypto_free_shash(tfm); + ima_free_tfm(tfm); return rc; }