From 8bba066f4e3854755a303cee37ea37bd080a46b3 Mon Sep 17 00:00:00 2001 From: Michael Halcrow Date: Mon, 30 Oct 2006 22:07:18 -0800 Subject: [PATCH] [PATCH] eCryptfs: Cipher code to new crypto API Update cipher block encryption code to the new crypto API. Signed-off-by: Michael Halcrow Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/ecryptfs/crypto.c | 92 ++++++++++++++++++++++++------- fs/ecryptfs/ecryptfs_kernel.h | 9 ++- fs/ecryptfs/keystore.c | 101 ++++++++++++++++++++++------------ fs/ecryptfs/main.c | 2 + 4 files changed, 146 insertions(+), 58 deletions(-) diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c index f14c5a38215e..2a1b6aa1a4a1 100644 --- a/fs/ecryptfs/crypto.c +++ b/fs/ecryptfs/crypto.c @@ -123,6 +123,28 @@ out: return rc; } +int ecryptfs_crypto_api_algify_cipher_name(char **algified_name, + char *cipher_name, + char *chaining_modifier) +{ + int cipher_name_len = strlen(cipher_name); + int chaining_modifier_len = strlen(chaining_modifier); + int algified_name_len; + int rc; + + algified_name_len = (chaining_modifier_len + cipher_name_len + 3); + (*algified_name) = kmalloc(algified_name_len, GFP_KERNEL); + if (!(algified_name)) { + rc = -ENOMEM; + goto out; + } + snprintf((*algified_name), algified_name_len, "%s(%s)", + chaining_modifier, cipher_name); + rc = 0; +out: + return rc; +} + /** * ecryptfs_derive_iv * @iv: destination for the derived iv vale @@ -197,7 +219,7 @@ ecryptfs_init_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat) void ecryptfs_destruct_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat) { if (crypt_stat->tfm) - crypto_free_tfm(crypt_stat->tfm); + crypto_free_blkcipher(crypt_stat->tfm); if (crypt_stat->hash_tfm) crypto_free_hash(crypt_stat->hash_tfm); memset(crypt_stat, 0, sizeof(struct ecryptfs_crypt_stat)); @@ -209,7 +231,7 @@ void ecryptfs_destruct_mount_crypt_stat( if (mount_crypt_stat->global_auth_tok_key) key_put(mount_crypt_stat->global_auth_tok_key); if (mount_crypt_stat->global_key_tfm) - crypto_free_tfm(mount_crypt_stat->global_key_tfm); + crypto_free_blkcipher(mount_crypt_stat->global_key_tfm); memset(mount_crypt_stat, 0, sizeof(struct ecryptfs_mount_crypt_stat)); } @@ -275,6 +297,11 @@ static int encrypt_scatterlist(struct ecryptfs_crypt_stat *crypt_stat, struct scatterlist *src_sg, int size, unsigned char *iv) { + struct blkcipher_desc desc = { + .tfm = crypt_stat->tfm, + .info = iv, + .flags = CRYPTO_TFM_REQ_MAY_SLEEP + }; int rc = 0; BUG_ON(!crypt_stat || !crypt_stat->tfm @@ -288,8 +315,8 @@ static int encrypt_scatterlist(struct ecryptfs_crypt_stat *crypt_stat, } /* Consider doing this once, when the file is opened */ mutex_lock(&crypt_stat->cs_tfm_mutex); - rc = crypto_cipher_setkey(crypt_stat->tfm, crypt_stat->key, - crypt_stat->key_size); + rc = crypto_blkcipher_setkey(crypt_stat->tfm, crypt_stat->key, + crypt_stat->key_size); if (rc) { ecryptfs_printk(KERN_ERR, "Error setting key; rc = [%d]\n", rc); @@ -298,7 +325,7 @@ static int encrypt_scatterlist(struct ecryptfs_crypt_stat *crypt_stat, goto out; } ecryptfs_printk(KERN_DEBUG, "Encrypting [%d] bytes.\n", size); - crypto_cipher_encrypt_iv(crypt_stat->tfm, dest_sg, src_sg, size, iv); + crypto_blkcipher_encrypt_iv(&desc, dest_sg, src_sg, size); mutex_unlock(&crypt_stat->cs_tfm_mutex); out: return rc; @@ -681,12 +708,17 @@ static int decrypt_scatterlist(struct ecryptfs_crypt_stat *crypt_stat, struct scatterlist *src_sg, int size, unsigned char *iv) { + struct blkcipher_desc desc = { + .tfm = crypt_stat->tfm, + .info = iv, + .flags = CRYPTO_TFM_REQ_MAY_SLEEP + }; int rc = 0; /* Consider doing this once, when the file is opened */ mutex_lock(&crypt_stat->cs_tfm_mutex); - rc = crypto_cipher_setkey(crypt_stat->tfm, crypt_stat->key, - crypt_stat->key_size); + rc = crypto_blkcipher_setkey(crypt_stat->tfm, crypt_stat->key, + crypt_stat->key_size); if (rc) { ecryptfs_printk(KERN_ERR, "Error setting key; rc = [%d]\n", rc); @@ -695,8 +727,7 @@ static int decrypt_scatterlist(struct ecryptfs_crypt_stat *crypt_stat, goto out; } ecryptfs_printk(KERN_DEBUG, "Decrypting [%d] bytes.\n", size); - rc = crypto_cipher_decrypt_iv(crypt_stat->tfm, dest_sg, src_sg, size, - iv); + rc = crypto_blkcipher_decrypt_iv(&desc, dest_sg, src_sg, size); mutex_unlock(&crypt_stat->cs_tfm_mutex); if (rc) { ecryptfs_printk(KERN_ERR, "Error decrypting; rc = [%d]\n", @@ -765,6 +796,7 @@ ecryptfs_decrypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat, */ int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat) { + char *full_alg_name; int rc = -EINVAL; if (!crypt_stat->cipher) { @@ -781,16 +813,24 @@ int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat) goto out; } mutex_lock(&crypt_stat->cs_tfm_mutex); - crypt_stat->tfm = crypto_alloc_tfm(crypt_stat->cipher, - ECRYPTFS_DEFAULT_CHAINING_MODE - | CRYPTO_TFM_REQ_WEAK_KEY); - mutex_unlock(&crypt_stat->cs_tfm_mutex); + rc = ecryptfs_crypto_api_algify_cipher_name(&full_alg_name, + crypt_stat->cipher, "cbc"); + if (rc) + goto out; + crypt_stat->tfm = crypto_alloc_blkcipher(full_alg_name, 0, + CRYPTO_ALG_ASYNC); + kfree(full_alg_name); if (!crypt_stat->tfm) { ecryptfs_printk(KERN_ERR, "cryptfs: init_crypt_ctx(): " "Error initializing cipher [%s]\n", crypt_stat->cipher); + mutex_unlock(&crypt_stat->cs_tfm_mutex); goto out; } + crypto_blkcipher_set_flags(crypt_stat->tfm, + (ECRYPTFS_DEFAULT_CHAINING_MODE + | CRYPTO_TFM_REQ_WEAK_KEY)); + mutex_unlock(&crypt_stat->cs_tfm_mutex); rc = 0; out: return rc; @@ -1588,10 +1628,11 @@ out: * event, regardless of whether this function succeeds for fails. */ int -ecryptfs_process_cipher(struct crypto_tfm **key_tfm, char *cipher_name, +ecryptfs_process_cipher(struct crypto_blkcipher **key_tfm, char *cipher_name, size_t *key_size) { char dummy_key[ECRYPTFS_MAX_KEY_BYTES]; + char *full_alg_name; int rc; *key_tfm = NULL; @@ -1601,17 +1642,26 @@ ecryptfs_process_cipher(struct crypto_tfm **key_tfm, char *cipher_name, "allowable is [%d]\n", *key_size, ECRYPTFS_MAX_KEY_BYTES); goto out; } - *key_tfm = crypto_alloc_tfm(cipher_name, CRYPTO_TFM_REQ_WEAK_KEY); - if (!(*key_tfm)) { - rc = -EINVAL; + rc = ecryptfs_crypto_api_algify_cipher_name(&full_alg_name, cipher_name, + "ecb"); + if (rc) + goto out; + *key_tfm = crypto_alloc_blkcipher(full_alg_name, 0, CRYPTO_ALG_ASYNC); + kfree(full_alg_name); + if (IS_ERR(*key_tfm)) { + rc = PTR_ERR(*key_tfm); printk(KERN_ERR "Unable to allocate crypto cipher with name " - "[%s]\n", cipher_name); + "[%s]; rc = [%d]\n", cipher_name, rc); goto out; } - if (*key_size == 0) - *key_size = crypto_tfm_alg_max_keysize(*key_tfm); + crypto_blkcipher_set_flags(*key_tfm, CRYPTO_TFM_REQ_WEAK_KEY); + if (*key_size == 0) { + struct blkcipher_alg *alg = crypto_blkcipher_alg(*key_tfm); + + *key_size = alg->max_keysize; + } get_random_bytes(dummy_key, *key_size); - rc = crypto_cipher_setkey(*key_tfm, dummy_key, *key_size); + rc = crypto_blkcipher_setkey(*key_tfm, dummy_key, *key_size); if (rc) { printk(KERN_ERR "Error attempting to set key of size [%Zd] for " "cipher [%s]; rc = [%d]\n", *key_size, cipher_name, rc); diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h index 840aa010e0d3..199fcda50e1b 100644 --- a/fs/ecryptfs/ecryptfs_kernel.h +++ b/fs/ecryptfs/ecryptfs_kernel.h @@ -205,7 +205,7 @@ struct ecryptfs_crypt_stat { size_t extent_shift; unsigned int extent_mask; struct ecryptfs_mount_crypt_stat *mount_crypt_stat; - struct crypto_tfm *tfm; + struct crypto_blkcipher *tfm; struct crypto_hash *hash_tfm; /* Crypto context for generating * the initialization vectors */ unsigned char cipher[ECRYPTFS_MAX_CIPHER_NAME_SIZE]; @@ -245,7 +245,7 @@ struct ecryptfs_mount_crypt_stat { struct ecryptfs_auth_tok *global_auth_tok; struct key *global_auth_tok_key; size_t global_default_cipher_key_size; - struct crypto_tfm *global_key_tfm; + struct crypto_blkcipher *global_key_tfm; struct mutex global_key_tfm_mutex; unsigned char global_default_cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE + 1]; @@ -426,6 +426,9 @@ void ecryptfs_destruct_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat); void ecryptfs_destruct_mount_crypt_stat( struct ecryptfs_mount_crypt_stat *mount_crypt_stat); int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat); +int ecryptfs_crypto_api_algify_cipher_name(char **algified_name, + char *cipher_name, + char *chaining_modifier); int ecryptfs_write_inode_size_to_header(struct file *lower_file, struct inode *lower_inode, struct inode *inode); @@ -474,7 +477,7 @@ ecryptfs_parse_packet_set(struct ecryptfs_crypt_stat *crypt_stat, unsigned char *src, struct dentry *ecryptfs_dentry); int ecryptfs_truncate(struct dentry *dentry, loff_t new_length); int -ecryptfs_process_cipher(struct crypto_tfm **key_tfm, char *cipher_name, +ecryptfs_process_cipher(struct crypto_blkcipher **key_tfm, char *cipher_name, size_t *key_size); int ecryptfs_inode_test(struct inode *inode, void *candidate_lower_inode); int ecryptfs_inode_set(struct inode *inode, void *lower_inode); diff --git a/fs/ecryptfs/keystore.c b/fs/ecryptfs/keystore.c index bc706d33559a..c3746f56d162 100644 --- a/fs/ecryptfs/keystore.c +++ b/fs/ecryptfs/keystore.c @@ -458,14 +458,16 @@ out: static int decrypt_session_key(struct ecryptfs_auth_tok *auth_tok, struct ecryptfs_crypt_stat *crypt_stat) { - int rc = 0; struct ecryptfs_password *password_s_ptr; - struct crypto_tfm *tfm = NULL; struct scatterlist src_sg[2], dst_sg[2]; struct mutex *tfm_mutex = NULL; /* TODO: Use virt_to_scatterlist for these */ char *encrypted_session_key; char *session_key; + struct blkcipher_desc desc = { + .flags = CRYPTO_TFM_REQ_MAY_SLEEP + }; + int rc = 0; password_s_ptr = &auth_tok->token.password; if (ECRYPTFS_CHECK_FLAG(password_s_ptr->flags, @@ -482,22 +484,32 @@ static int decrypt_session_key(struct ecryptfs_auth_tok *auth_tok, if (!strcmp(crypt_stat->cipher, crypt_stat->mount_crypt_stat->global_default_cipher_name) && crypt_stat->mount_crypt_stat->global_key_tfm) { - tfm = crypt_stat->mount_crypt_stat->global_key_tfm; + desc.tfm = crypt_stat->mount_crypt_stat->global_key_tfm; tfm_mutex = &crypt_stat->mount_crypt_stat->global_key_tfm_mutex; } else { - tfm = crypto_alloc_tfm(crypt_stat->cipher, - CRYPTO_TFM_REQ_WEAK_KEY); - if (!tfm) { - printk(KERN_ERR "Error allocating crypto context\n"); - rc = -ENOMEM; + char *full_alg_name; + + rc = ecryptfs_crypto_api_algify_cipher_name(&full_alg_name, + crypt_stat->cipher, + "ecb"); + if (rc) + goto out; + desc.tfm = crypto_alloc_blkcipher(full_alg_name, 0, + CRYPTO_ALG_ASYNC); + kfree(full_alg_name); + if (IS_ERR(desc.tfm)) { + rc = PTR_ERR(desc.tfm); + printk(KERN_ERR "Error allocating crypto context; " + "rc = [%d]\n", rc); goto out; } + crypto_blkcipher_set_flags(desc.tfm, CRYPTO_TFM_REQ_WEAK_KEY); } if (tfm_mutex) mutex_lock(tfm_mutex); - rc = crypto_cipher_setkey(tfm, - password_s_ptr->session_key_encryption_key, - crypt_stat->key_size); + rc = crypto_blkcipher_setkey(desc.tfm, + password_s_ptr->session_key_encryption_key, + crypt_stat->key_size); if (rc < 0) { printk(KERN_ERR "Error setting key for crypto context\n"); rc = -EINVAL; @@ -528,9 +540,12 @@ static int decrypt_session_key(struct ecryptfs_auth_tok *auth_tok, auth_tok->session_key.decrypted_key_size = auth_tok->session_key.encrypted_key_size; dst_sg[0].length = auth_tok->session_key.encrypted_key_size; - /* TODO: Handle error condition */ - crypto_cipher_decrypt(tfm, dst_sg, src_sg, - auth_tok->session_key.encrypted_key_size); + rc = crypto_blkcipher_decrypt(&desc, dst_sg, src_sg, + auth_tok->session_key.encrypted_key_size); + if (rc) { + printk(KERN_ERR "Error decrypting; rc = [%d]\n", rc); + goto out_free_memory; + } auth_tok->session_key.decrypted_key_size = auth_tok->session_key.encrypted_key_size; memcpy(auth_tok->session_key.decrypted_key, session_key, @@ -543,6 +558,7 @@ static int decrypt_session_key(struct ecryptfs_auth_tok *auth_tok, if (ecryptfs_verbosity > 0) ecryptfs_dump_hex(crypt_stat->key, crypt_stat->key_size); +out_free_memory: memset(encrypted_session_key, 0, PAGE_CACHE_SIZE); free_page((unsigned long)encrypted_session_key); memset(session_key, 0, PAGE_CACHE_SIZE); @@ -551,7 +567,7 @@ out_free_tfm: if (tfm_mutex) mutex_unlock(tfm_mutex); else - crypto_free_tfm(tfm); + crypto_free_blkcipher(desc.tfm); out: return rc; } @@ -800,19 +816,21 @@ write_tag_3_packet(char *dest, size_t max, struct ecryptfs_auth_tok *auth_tok, struct ecryptfs_crypt_stat *crypt_stat, struct ecryptfs_key_record *key_rec, size_t *packet_size) { - int rc = 0; - size_t i; size_t signature_is_valid = 0; size_t encrypted_session_key_valid = 0; char session_key_encryption_key[ECRYPTFS_MAX_KEY_BYTES]; struct scatterlist dest_sg[2]; struct scatterlist src_sg[2]; - struct crypto_tfm *tfm = NULL; struct mutex *tfm_mutex = NULL; size_t key_rec_size; size_t packet_size_length; size_t cipher_code; + struct blkcipher_desc desc = { + .tfm = NULL, + .flags = CRYPTO_TFM_REQ_MAY_SLEEP + }; + int rc = 0; (*packet_size) = 0; /* Check for a valid signature on the auth_tok */ @@ -879,33 +897,48 @@ write_tag_3_packet(char *dest, size_t max, struct ecryptfs_auth_tok *auth_tok, if (!strcmp(crypt_stat->cipher, crypt_stat->mount_crypt_stat->global_default_cipher_name) && crypt_stat->mount_crypt_stat->global_key_tfm) { - tfm = crypt_stat->mount_crypt_stat->global_key_tfm; + desc.tfm = crypt_stat->mount_crypt_stat->global_key_tfm; tfm_mutex = &crypt_stat->mount_crypt_stat->global_key_tfm_mutex; - } else - tfm = crypto_alloc_tfm(crypt_stat->cipher, 0); - if (!tfm) { - ecryptfs_printk(KERN_ERR, "Could not initialize crypto " - "context for cipher [%s]\n", - crypt_stat->cipher); - rc = -EINVAL; - goto out; + } else { + char *full_alg_name; + + rc = ecryptfs_crypto_api_algify_cipher_name(&full_alg_name, + crypt_stat->cipher, + "ecb"); + if (rc) + goto out; + desc.tfm = crypto_alloc_blkcipher(full_alg_name, 0, + CRYPTO_ALG_ASYNC); + kfree(full_alg_name); + if (IS_ERR(desc.tfm)) { + rc = PTR_ERR(desc.tfm); + ecryptfs_printk(KERN_ERR, "Could not initialize crypto " + "context for cipher [%s]; rc = [%d]\n", + crypt_stat->cipher, rc); + goto out; + } + crypto_blkcipher_set_flags(desc.tfm, CRYPTO_TFM_REQ_WEAK_KEY); } if (tfm_mutex) mutex_lock(tfm_mutex); - rc = crypto_cipher_setkey(tfm, session_key_encryption_key, - crypt_stat->key_size); + rc = crypto_blkcipher_setkey(desc.tfm, session_key_encryption_key, + crypt_stat->key_size); if (rc < 0) { if (tfm_mutex) mutex_unlock(tfm_mutex); ecryptfs_printk(KERN_ERR, "Error setting key for crypto " - "context\n"); + "context; rc = [%d]\n", rc); goto out; } rc = 0; ecryptfs_printk(KERN_DEBUG, "Encrypting [%d] bytes of the key\n", crypt_stat->key_size); - crypto_cipher_encrypt(tfm, dest_sg, src_sg, - (*key_rec).enc_key_size); + rc = crypto_blkcipher_encrypt(&desc, dest_sg, src_sg, + (*key_rec).enc_key_size); + if (rc) { + printk(KERN_ERR "Error encrypting; rc = [%d]\n", rc); + goto out; + } if (tfm_mutex) mutex_unlock(tfm_mutex); ecryptfs_printk(KERN_DEBUG, "This should be the encrypted key:\n"); @@ -968,8 +1001,8 @@ encrypted_session_key_set: (*key_rec).enc_key_size); (*packet_size) += (*key_rec).enc_key_size; out: - if (tfm && !tfm_mutex) - crypto_free_tfm(tfm); + if (desc.tfm && !tfm_mutex) + crypto_free_blkcipher(desc.tfm); if (rc) (*packet_size) = 0; return rc; diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c index a65f4865182c..a78d87d14baf 100644 --- a/fs/ecryptfs/main.c +++ b/fs/ecryptfs/main.c @@ -315,6 +315,8 @@ static int ecryptfs_parse_options(struct super_block *sb, char *options) "with key size [%Zd] bytes; rc = [%d]\n", mount_crypt_stat->global_default_cipher_name, mount_crypt_stat->global_default_cipher_key_size, rc); + mount_crypt_stat->global_key_tfm = NULL; + mount_crypt_stat->global_auth_tok_key = NULL; rc = -EINVAL; goto out; } -- 2.20.1