diff options
Diffstat (limited to 'fs/ecryptfs/crypto.c')
-rw-r--r-- | fs/ecryptfs/crypto.c | 398 |
1 files changed, 137 insertions, 261 deletions
diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c index ea9931281557..d10757635b9c 100644 --- a/fs/ecryptfs/crypto.c +++ b/fs/ecryptfs/crypto.c @@ -37,16 +37,8 @@ #include <asm/unaligned.h> #include "ecryptfs_kernel.h" -static int -ecryptfs_decrypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat, - struct page *dst_page, int dst_offset, - struct page *src_page, int src_offset, int size, - unsigned char *iv); -static int -ecryptfs_encrypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat, - struct page *dst_page, int dst_offset, - struct page *src_page, int src_offset, int size, - unsigned char *iv); +#define DECRYPT 0 +#define ENCRYPT 1 /** * ecryptfs_to_hex @@ -243,7 +235,7 @@ void ecryptfs_destroy_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat) struct ecryptfs_key_sig *key_sig, *key_sig_tmp; if (crypt_stat->tfm) - crypto_free_blkcipher(crypt_stat->tfm); + crypto_free_ablkcipher(crypt_stat->tfm); if (crypt_stat->hash_tfm) crypto_free_hash(crypt_stat->hash_tfm); list_for_each_entry_safe(key_sig, key_sig_tmp, @@ -301,17 +293,14 @@ int virt_to_scatterlist(const void *addr, int size, struct scatterlist *sg, while (size > 0 && i < sg_size) { pg = virt_to_page(addr); offset = offset_in_page(addr); - if (sg) - sg_set_page(&sg[i], pg, 0, offset); + sg_set_page(&sg[i], pg, 0, offset); remainder_of_page = PAGE_CACHE_SIZE - offset; if (size >= remainder_of_page) { - if (sg) - sg[i].length = remainder_of_page; + sg[i].length = remainder_of_page; addr += remainder_of_page; size -= remainder_of_page; } else { - if (sg) - sg[i].length = size; + sg[i].length = size; addr += size; size = 0; } @@ -322,26 +311,40 @@ int virt_to_scatterlist(const void *addr, int size, struct scatterlist *sg, return i; } +struct extent_crypt_result { + struct completion completion; + int rc; +}; + +static void extent_crypt_complete(struct crypto_async_request *req, int rc) +{ + struct extent_crypt_result *ecr = req->data; + + if (rc == -EINPROGRESS) + return; + + ecr->rc = rc; + complete(&ecr->completion); +} + /** - * encrypt_scatterlist + * crypt_scatterlist * @crypt_stat: Pointer to the crypt_stat struct to initialize. - * @dest_sg: Destination of encrypted data - * @src_sg: Data to be encrypted - * @size: Length of data to be encrypted - * @iv: iv to use during encryption + * @dst_sg: Destination of the data after performing the crypto operation + * @src_sg: Data to be encrypted or decrypted + * @size: Length of data + * @iv: IV to use + * @op: ENCRYPT or DECRYPT to indicate the desired operation * - * Returns the number of bytes encrypted; negative value on error + * Returns the number of bytes encrypted or decrypted; negative value on error */ -static int encrypt_scatterlist(struct ecryptfs_crypt_stat *crypt_stat, - struct scatterlist *dest_sg, - struct scatterlist *src_sg, int size, - unsigned char *iv) +static int crypt_scatterlist(struct ecryptfs_crypt_stat *crypt_stat, + struct scatterlist *dst_sg, + struct scatterlist *src_sg, int size, + unsigned char *iv, int op) { - struct blkcipher_desc desc = { - .tfm = crypt_stat->tfm, - .info = iv, - .flags = CRYPTO_TFM_REQ_MAY_SLEEP - }; + struct ablkcipher_request *req = NULL; + struct extent_crypt_result ecr; int rc = 0; BUG_ON(!crypt_stat || !crypt_stat->tfm @@ -352,63 +355,88 @@ static int encrypt_scatterlist(struct ecryptfs_crypt_stat *crypt_stat, ecryptfs_dump_hex(crypt_stat->key, crypt_stat->key_size); } - /* Consider doing this once, when the file is opened */ + + init_completion(&ecr.completion); + mutex_lock(&crypt_stat->cs_tfm_mutex); - if (!(crypt_stat->flags & ECRYPTFS_KEY_SET)) { - rc = crypto_blkcipher_setkey(crypt_stat->tfm, crypt_stat->key, - crypt_stat->key_size); - crypt_stat->flags |= ECRYPTFS_KEY_SET; - } - if (rc) { - ecryptfs_printk(KERN_ERR, "Error setting key; rc = [%d]\n", - rc); + req = ablkcipher_request_alloc(crypt_stat->tfm, GFP_NOFS); + if (!req) { mutex_unlock(&crypt_stat->cs_tfm_mutex); - rc = -EINVAL; + rc = -ENOMEM; goto out; } - ecryptfs_printk(KERN_DEBUG, "Encrypting [%d] bytes.\n", size); - crypto_blkcipher_encrypt_iv(&desc, dest_sg, src_sg, size); + + ablkcipher_request_set_callback(req, + CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP, + extent_crypt_complete, &ecr); + /* Consider doing this once, when the file is opened */ + if (!(crypt_stat->flags & ECRYPTFS_KEY_SET)) { + rc = crypto_ablkcipher_setkey(crypt_stat->tfm, crypt_stat->key, + crypt_stat->key_size); + if (rc) { + ecryptfs_printk(KERN_ERR, + "Error setting key; rc = [%d]\n", + rc); + mutex_unlock(&crypt_stat->cs_tfm_mutex); + rc = -EINVAL; + goto out; + } + crypt_stat->flags |= ECRYPTFS_KEY_SET; + } mutex_unlock(&crypt_stat->cs_tfm_mutex); + ablkcipher_request_set_crypt(req, src_sg, dst_sg, size, iv); + rc = op == ENCRYPT ? crypto_ablkcipher_encrypt(req) : + crypto_ablkcipher_decrypt(req); + if (rc == -EINPROGRESS || rc == -EBUSY) { + struct extent_crypt_result *ecr = req->base.data; + + wait_for_completion(&ecr->completion); + rc = ecr->rc; + INIT_COMPLETION(ecr->completion); + } out: + ablkcipher_request_free(req); return rc; } /** - * ecryptfs_lower_offset_for_extent + * lower_offset_for_page * * Convert an eCryptfs page index into a lower byte offset */ -static void ecryptfs_lower_offset_for_extent(loff_t *offset, loff_t extent_num, - struct ecryptfs_crypt_stat *crypt_stat) +static loff_t lower_offset_for_page(struct ecryptfs_crypt_stat *crypt_stat, + struct page *page) { - (*offset) = ecryptfs_lower_header_size(crypt_stat) - + (crypt_stat->extent_size * extent_num); + return ecryptfs_lower_header_size(crypt_stat) + + (page->index << PAGE_CACHE_SHIFT); } /** - * ecryptfs_encrypt_extent - * @enc_extent_page: Allocated page into which to encrypt the data in - * @page + * crypt_extent * @crypt_stat: crypt_stat containing cryptographic context for the * encryption operation - * @page: Page containing plaintext data extent to encrypt + * @dst_page: The page to write the result into + * @src_page: The page to read from * @extent_offset: Page extent offset for use in generating IV + * @op: ENCRYPT or DECRYPT to indicate the desired operation * - * Encrypts one extent of data. + * Encrypts or decrypts one extent of data. * * Return zero on success; non-zero otherwise */ -static int ecryptfs_encrypt_extent(struct page *enc_extent_page, - struct ecryptfs_crypt_stat *crypt_stat, - struct page *page, - unsigned long extent_offset) +static int crypt_extent(struct ecryptfs_crypt_stat *crypt_stat, + struct page *dst_page, + struct page *src_page, + unsigned long extent_offset, int op) { + pgoff_t page_index = op == ENCRYPT ? src_page->index : dst_page->index; loff_t extent_base; char extent_iv[ECRYPTFS_MAX_IV_BYTES]; + struct scatterlist src_sg, dst_sg; + size_t extent_size = crypt_stat->extent_size; int rc; - extent_base = (((loff_t)page->index) - * (PAGE_CACHE_SIZE / crypt_stat->extent_size)); + extent_base = (((loff_t)page_index) * (PAGE_CACHE_SIZE / extent_size)); rc = ecryptfs_derive_iv(extent_iv, crypt_stat, (extent_base + extent_offset)); if (rc) { @@ -417,15 +445,21 @@ static int ecryptfs_encrypt_extent(struct page *enc_extent_page, (unsigned long long)(extent_base + extent_offset), rc); goto out; } - rc = ecryptfs_encrypt_page_offset(crypt_stat, enc_extent_page, 0, - page, (extent_offset - * crypt_stat->extent_size), - crypt_stat->extent_size, extent_iv); + + sg_init_table(&src_sg, 1); + sg_init_table(&dst_sg, 1); + + sg_set_page(&src_sg, src_page, extent_size, + extent_offset * extent_size); + sg_set_page(&dst_sg, dst_page, extent_size, + extent_offset * extent_size); + + rc = crypt_scatterlist(crypt_stat, &dst_sg, &src_sg, extent_size, + extent_iv, op); if (rc < 0) { - printk(KERN_ERR "%s: Error attempting to encrypt page with " - "page->index = [%ld], extent_offset = [%ld]; " - "rc = [%d]\n", __func__, page->index, extent_offset, - rc); + printk(KERN_ERR "%s: Error attempting to crypt page with " + "page_index = [%ld], extent_offset = [%ld]; " + "rc = [%d]\n", __func__, page_index, extent_offset, rc); goto out; } rc = 0; @@ -456,6 +490,7 @@ int ecryptfs_encrypt_page(struct page *page) char *enc_extent_virt; struct page *enc_extent_page = NULL; loff_t extent_offset; + loff_t lower_offset; int rc = 0; ecryptfs_inode = page->mapping->host; @@ -469,75 +504,35 @@ int ecryptfs_encrypt_page(struct page *page) "encrypted extent\n"); goto out; } - enc_extent_virt = kmap(enc_extent_page); + for (extent_offset = 0; extent_offset < (PAGE_CACHE_SIZE / crypt_stat->extent_size); extent_offset++) { - loff_t offset; - - rc = ecryptfs_encrypt_extent(enc_extent_page, crypt_stat, page, - extent_offset); + rc = crypt_extent(crypt_stat, enc_extent_page, page, + extent_offset, ENCRYPT); if (rc) { printk(KERN_ERR "%s: Error encrypting extent; " "rc = [%d]\n", __func__, rc); goto out; } - ecryptfs_lower_offset_for_extent( - &offset, ((((loff_t)page->index) - * (PAGE_CACHE_SIZE - / crypt_stat->extent_size)) - + extent_offset), crypt_stat); - rc = ecryptfs_write_lower(ecryptfs_inode, enc_extent_virt, - offset, crypt_stat->extent_size); - if (rc < 0) { - ecryptfs_printk(KERN_ERR, "Error attempting " - "to write lower page; rc = [%d]" - "\n", rc); - goto out; - } } - rc = 0; -out: - if (enc_extent_page) { - kunmap(enc_extent_page); - __free_page(enc_extent_page); - } - return rc; -} -static int ecryptfs_decrypt_extent(struct page *page, - struct ecryptfs_crypt_stat *crypt_stat, - struct page *enc_extent_page, - unsigned long extent_offset) -{ - loff_t extent_base; - char extent_iv[ECRYPTFS_MAX_IV_BYTES]; - int rc; - - extent_base = (((loff_t)page->index) - * (PAGE_CACHE_SIZE / crypt_stat->extent_size)); - rc = ecryptfs_derive_iv(extent_iv, crypt_stat, - (extent_base + extent_offset)); - if (rc) { - ecryptfs_printk(KERN_ERR, "Error attempting to derive IV for " - "extent [0x%.16llx]; rc = [%d]\n", - (unsigned long long)(extent_base + extent_offset), rc); - goto out; - } - rc = ecryptfs_decrypt_page_offset(crypt_stat, page, - (extent_offset - * crypt_stat->extent_size), - enc_extent_page, 0, - crypt_stat->extent_size, extent_iv); + lower_offset = lower_offset_for_page(crypt_stat, page); + enc_extent_virt = kmap(enc_extent_page); + rc = ecryptfs_write_lower(ecryptfs_inode, enc_extent_virt, lower_offset, + PAGE_CACHE_SIZE); + kunmap(enc_extent_page); if (rc < 0) { - printk(KERN_ERR "%s: Error attempting to decrypt to page with " - "page->index = [%ld], extent_offset = [%ld]; " - "rc = [%d]\n", __func__, page->index, extent_offset, - rc); + ecryptfs_printk(KERN_ERR, + "Error attempting to write lower page; rc = [%d]\n", + rc); goto out; } rc = 0; out: + if (enc_extent_page) { + __free_page(enc_extent_page); + } return rc; } @@ -561,43 +556,33 @@ int ecryptfs_decrypt_page(struct page *page) { struct inode *ecryptfs_inode; struct ecryptfs_crypt_stat *crypt_stat; - char *enc_extent_virt; - struct page *enc_extent_page = NULL; + char *page_virt; unsigned long extent_offset; + loff_t lower_offset; int rc = 0; ecryptfs_inode = page->mapping->host; crypt_stat = &(ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat); BUG_ON(!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)); - enc_extent_page = alloc_page(GFP_USER); - if (!enc_extent_page) { - rc = -ENOMEM; - ecryptfs_printk(KERN_ERR, "Error allocating memory for " - "encrypted extent\n"); + + lower_offset = lower_offset_for_page(crypt_stat, page); + page_virt = kmap(page); + rc = ecryptfs_read_lower(page_virt, lower_offset, PAGE_CACHE_SIZE, + ecryptfs_inode); + kunmap(page); + if (rc < 0) { + ecryptfs_printk(KERN_ERR, + "Error attempting to read lower page; rc = [%d]\n", + rc); goto out; } - enc_extent_virt = kmap(enc_extent_page); + for (extent_offset = 0; extent_offset < (PAGE_CACHE_SIZE / crypt_stat->extent_size); extent_offset++) { - loff_t offset; - - ecryptfs_lower_offset_for_extent( - &offset, ((page->index * (PAGE_CACHE_SIZE - / crypt_stat->extent_size)) - + extent_offset), crypt_stat); - rc = ecryptfs_read_lower(enc_extent_virt, offset, - crypt_stat->extent_size, - ecryptfs_inode); - if (rc < 0) { - ecryptfs_printk(KERN_ERR, "Error attempting " - "to read lower page; rc = [%d]" - "\n", rc); - goto out; - } - rc = ecryptfs_decrypt_extent(page, crypt_stat, enc_extent_page, - extent_offset); + rc = crypt_extent(crypt_stat, page, page, + extent_offset, DECRYPT); if (rc) { printk(KERN_ERR "%s: Error encrypting extent; " "rc = [%d]\n", __func__, rc); @@ -605,116 +590,9 @@ int ecryptfs_decrypt_page(struct page *page) } } out: - if (enc_extent_page) { - kunmap(enc_extent_page); - __free_page(enc_extent_page); - } - return rc; -} - -/** - * decrypt_scatterlist - * @crypt_stat: Cryptographic context - * @dest_sg: The destination scatterlist to decrypt into - * @src_sg: The source scatterlist to decrypt from - * @size: The number of bytes to decrypt - * @iv: The initialization vector to use for the decryption - * - * Returns the number of bytes decrypted; negative value on error - */ -static int decrypt_scatterlist(struct ecryptfs_crypt_stat *crypt_stat, - struct scatterlist *dest_sg, - 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_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); - mutex_unlock(&crypt_stat->cs_tfm_mutex); - rc = -EINVAL; - goto out; - } - ecryptfs_printk(KERN_DEBUG, "Decrypting [%d] bytes.\n", size); - 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", - rc); - goto out; - } - rc = size; -out: return rc; } -/** - * ecryptfs_encrypt_page_offset - * @crypt_stat: The cryptographic context - * @dst_page: The page to encrypt into - * @dst_offset: The offset in the page to encrypt into - * @src_page: The page to encrypt from - * @src_offset: The offset in the page to encrypt from - * @size: The number of bytes to encrypt - * @iv: The initialization vector to use for the encryption - * - * Returns the number of bytes encrypted - */ -static int -ecryptfs_encrypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat, - struct page *dst_page, int dst_offset, - struct page *src_page, int src_offset, int size, - unsigned char *iv) -{ - struct scatterlist src_sg, dst_sg; - - sg_init_table(&src_sg, 1); - sg_init_table(&dst_sg, 1); - - sg_set_page(&src_sg, src_page, size, src_offset); - sg_set_page(&dst_sg, dst_page, size, dst_offset); - return encrypt_scatterlist(crypt_stat, &dst_sg, &src_sg, size, iv); -} - -/** - * ecryptfs_decrypt_page_offset - * @crypt_stat: The cryptographic context - * @dst_page: The page to decrypt into - * @dst_offset: The offset in the page to decrypt into - * @src_page: The page to decrypt from - * @src_offset: The offset in the page to decrypt from - * @size: The number of bytes to decrypt - * @iv: The initialization vector to use for the decryption - * - * Returns the number of bytes decrypted - */ -static int -ecryptfs_decrypt_page_offset(struct ecryptfs_crypt_stat *crypt_stat, - struct page *dst_page, int dst_offset, - struct page *src_page, int src_offset, int size, - unsigned char *iv) -{ - struct scatterlist src_sg, dst_sg; - - sg_init_table(&src_sg, 1); - sg_set_page(&src_sg, src_page, size, src_offset); - - sg_init_table(&dst_sg, 1); - sg_set_page(&dst_sg, dst_page, size, dst_offset); - - return decrypt_scatterlist(crypt_stat, &dst_sg, &src_sg, size, iv); -} - #define ECRYPTFS_MAX_SCATTERLIST_LEN 4 /** @@ -749,8 +627,7 @@ int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat) crypt_stat->cipher, "cbc"); if (rc) goto out_unlock; - crypt_stat->tfm = crypto_alloc_blkcipher(full_alg_name, 0, - CRYPTO_ALG_ASYNC); + crypt_stat->tfm = crypto_alloc_ablkcipher(full_alg_name, 0, 0); kfree(full_alg_name); if (IS_ERR(crypt_stat->tfm)) { rc = PTR_ERR(crypt_stat->tfm); @@ -760,7 +637,7 @@ int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat) crypt_stat->cipher); goto out_unlock; } - crypto_blkcipher_set_flags(crypt_stat->tfm, CRYPTO_TFM_REQ_WEAK_KEY); + crypto_ablkcipher_set_flags(crypt_stat->tfm, CRYPTO_TFM_REQ_WEAK_KEY); rc = 0; out_unlock: mutex_unlock(&crypt_stat->cs_tfm_mutex); @@ -1935,7 +1812,7 @@ static const unsigned char filename_rev_map[256] = { * @src: Source location for the filename to encode * @src_size: Size of the source in bytes */ -void ecryptfs_encode_for_filename(unsigned char *dst, size_t *dst_size, +static void ecryptfs_encode_for_filename(unsigned char *dst, size_t *dst_size, unsigned char *src, size_t src_size) { size_t num_blocks; @@ -2185,12 +2062,11 @@ out: */ int ecryptfs_decode_and_decrypt_filename(char **plaintext_name, size_t *plaintext_name_size, - struct dentry *ecryptfs_dir_dentry, + struct super_block *sb, const char *name, size_t name_size) { struct ecryptfs_mount_crypt_stat *mount_crypt_stat = - &ecryptfs_superblock_to_private( - ecryptfs_dir_dentry->d_sb)->mount_crypt_stat; + &ecryptfs_superblock_to_private(sb)->mount_crypt_stat; char *decoded_name; size_t decoded_name_size; size_t packet_size; |