*
* Copyright (C) 1997-2004 Erez Zadok
* Copyright (C) 2001-2004 Stony Brook University
- * Copyright (C) 2004-2006 International Business Machines Corp.
+ * Copyright (C) 2004-2007 International Business Machines Corp.
* Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
* Michael C. Thompson <mcthomps@us.ibm.com>
*
#include <linux/crypto.h>
#include <linux/file.h>
#include <linux/scatterlist.h>
+#include <asm/unaligned.h>
#include "ecryptfs_kernel.h"
static int
struct ecryptfs_crypt_stat *crypt_stat,
char *src, int len)
{
- int rc = 0;
struct scatterlist sg;
+ struct hash_desc desc = {
+ .tfm = crypt_stat->hash_tfm,
+ .flags = CRYPTO_TFM_REQ_MAY_SLEEP
+ };
+ int rc = 0;
- mutex_lock(&crypt_stat->cs_md5_tfm_mutex);
+ mutex_lock(&crypt_stat->cs_hash_tfm_mutex);
sg_init_one(&sg, (u8 *)src, len);
- if (!crypt_stat->md5_tfm) {
- crypt_stat->md5_tfm =
- crypto_alloc_tfm("md5", CRYPTO_TFM_REQ_MAY_SLEEP);
- if (!crypt_stat->md5_tfm) {
- rc = -ENOMEM;
+ if (!desc.tfm) {
+ desc.tfm = crypto_alloc_hash(ECRYPTFS_DEFAULT_HASH, 0,
+ CRYPTO_ALG_ASYNC);
+ if (IS_ERR(desc.tfm)) {
+ rc = PTR_ERR(desc.tfm);
ecryptfs_printk(KERN_ERR, "Error attempting to "
- "allocate crypto context\n");
+ "allocate crypto context; rc = [%d]\n",
+ rc);
goto out;
}
+ crypt_stat->hash_tfm = desc.tfm;
+ }
+ rc = crypto_hash_init(&desc);
+ if (rc) {
+ printk(KERN_ERR
+ "%s: Error initializing crypto hash; rc = [%d]\n",
+ __func__, rc);
+ goto out;
+ }
+ rc = crypto_hash_update(&desc, &sg, len);
+ if (rc) {
+ printk(KERN_ERR
+ "%s: Error updating crypto hash; rc = [%d]\n",
+ __func__, rc);
+ goto out;
+ }
+ rc = crypto_hash_final(&desc, dst);
+ if (rc) {
+ printk(KERN_ERR
+ "%s: Error finalizing crypto hash; rc = [%d]\n",
+ __func__, rc);
+ goto out;
+ }
+out:
+ mutex_unlock(&crypt_stat->cs_hash_tfm_mutex);
+ return rc;
+}
+
+static 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;
}
- crypto_digest_init(crypt_stat->md5_tfm);
- crypto_digest_update(crypt_stat->md5_tfm, &sg, 1);
- crypto_digest_final(crypt_stat->md5_tfm, dst);
- mutex_unlock(&crypt_stat->cs_md5_tfm_mutex);
+ 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
* @crypt_stat: Pointer to crypt_stat struct for the current inode
- * @offset: Offset of the page whose's iv we are to derive
+ * @offset: Offset of the extent whose IV we are to derive
*
* Generate the initialization vector from the given root IV and page
* offset.
*
* Returns zero on success; non-zero on error.
*/
-static int ecryptfs_derive_iv(char *iv, struct ecryptfs_crypt_stat *crypt_stat,
- pgoff_t offset)
+int ecryptfs_derive_iv(char *iv, struct ecryptfs_crypt_stat *crypt_stat,
+ loff_t offset)
{
int rc = 0;
char dst[MD5_DIGEST_SIZE];
* hashing business. -Halcrow */
memcpy(src, crypt_stat->root_iv, crypt_stat->iv_bytes);
memset((src + crypt_stat->iv_bytes), 0, 16);
- snprintf((src + crypt_stat->iv_bytes), 16, "%ld", offset);
+ snprintf((src + crypt_stat->iv_bytes), 16, "%lld", offset);
if (unlikely(ecryptfs_verbosity > 0)) {
ecryptfs_printk(KERN_DEBUG, "source:\n");
ecryptfs_dump_hex(src, (crypt_stat->iv_bytes + 16));
ecryptfs_init_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat)
{
memset((void *)crypt_stat, 0, sizeof(struct ecryptfs_crypt_stat));
+ INIT_LIST_HEAD(&crypt_stat->keysig_list);
+ mutex_init(&crypt_stat->keysig_list_mutex);
mutex_init(&crypt_stat->cs_mutex);
mutex_init(&crypt_stat->cs_tfm_mutex);
- mutex_init(&crypt_stat->cs_md5_tfm_mutex);
- ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_STRUCT_INITIALIZED);
+ mutex_init(&crypt_stat->cs_hash_tfm_mutex);
+ crypt_stat->flags |= ECRYPTFS_STRUCT_INITIALIZED;
}
/**
- * ecryptfs_destruct_crypt_stat
+ * ecryptfs_destroy_crypt_stat
* @crypt_stat: Pointer to the crypt_stat struct to initialize.
*
* Releases all memory associated with a crypt_stat struct.
*/
-void ecryptfs_destruct_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat)
+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_tfm(crypt_stat->tfm);
- if (crypt_stat->md5_tfm)
- crypto_free_tfm(crypt_stat->md5_tfm);
+ crypto_free_blkcipher(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,
+ &crypt_stat->keysig_list, crypt_stat_list) {
+ list_del(&key_sig->crypt_stat_list);
+ kmem_cache_free(ecryptfs_key_sig_cache, key_sig);
+ }
memset(crypt_stat, 0, sizeof(struct ecryptfs_crypt_stat));
}
-void ecryptfs_destruct_mount_crypt_stat(
+void ecryptfs_destroy_mount_crypt_stat(
struct ecryptfs_mount_crypt_stat *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);
+ struct ecryptfs_global_auth_tok *auth_tok, *auth_tok_tmp;
+
+ if (!(mount_crypt_stat->flags & ECRYPTFS_MOUNT_CRYPT_STAT_INITIALIZED))
+ return;
+ mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex);
+ list_for_each_entry_safe(auth_tok, auth_tok_tmp,
+ &mount_crypt_stat->global_auth_tok_list,
+ mount_crypt_stat_list) {
+ list_del(&auth_tok->mount_crypt_stat_list);
+ mount_crypt_stat->num_global_auth_toks--;
+ if (auth_tok->global_auth_tok_key
+ && !(auth_tok->flags & ECRYPTFS_AUTH_TOK_INVALID))
+ key_put(auth_tok->global_auth_tok_key);
+ kmem_cache_free(ecryptfs_global_auth_tok_cache, auth_tok);
+ }
+ mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex);
memset(mount_crypt_stat, 0, sizeof(struct ecryptfs_mount_crypt_stat));
}
int offset;
int remainder_of_page;
+ sg_init_table(sg, sg_size);
+
while (size > 0 && i < sg_size) {
pg = virt_to_page(addr);
offset = offset_in_page(addr);
- if (sg) {
- sg[i].page = pg;
- sg[i].offset = offset;
- }
+ if (sg)
+ sg_set_page(&sg[i], pg, 0, offset);
remainder_of_page = PAGE_CACHE_SIZE - offset;
if (size >= remainder_of_page) {
if (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;
BUG_ON(!crypt_stat || !crypt_stat->tfm
- || !ECRYPTFS_CHECK_FLAG(crypt_stat->flags,
- ECRYPTFS_STRUCT_INITIALIZED));
+ || !(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED));
if (unlikely(ecryptfs_verbosity > 0)) {
ecryptfs_printk(KERN_DEBUG, "Key size [%d]; key:\n",
crypt_stat->key_size);
}
/* 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);
+ 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);
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;
}
-static void
-ecryptfs_extent_to_lwr_pg_idx_and_offset(unsigned long *lower_page_idx,
- int *byte_offset,
- struct ecryptfs_crypt_stat *crypt_stat,
- unsigned long extent_num)
+/**
+ * ecryptfs_lower_offset_for_extent
+ *
+ * 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)
{
- unsigned long lower_extent_num;
- int extents_occupied_by_headers_at_front;
- int bytes_occupied_by_headers_at_front;
- int extent_offset;
- int extents_per_page;
-
- bytes_occupied_by_headers_at_front =
- ( crypt_stat->header_extent_size
- * crypt_stat->num_header_extents_at_front );
- extents_occupied_by_headers_at_front =
- ( bytes_occupied_by_headers_at_front
- / crypt_stat->extent_size );
- lower_extent_num = extents_occupied_by_headers_at_front + extent_num;
- extents_per_page = PAGE_CACHE_SIZE / crypt_stat->extent_size;
- (*lower_page_idx) = lower_extent_num / extents_per_page;
- extent_offset = lower_extent_num % extents_per_page;
- (*byte_offset) = extent_offset * crypt_stat->extent_size;
- ecryptfs_printk(KERN_DEBUG, " * crypt_stat->header_extent_size = "
- "[%d]\n", crypt_stat->header_extent_size);
- ecryptfs_printk(KERN_DEBUG, " * crypt_stat->"
- "num_header_extents_at_front = [%d]\n",
- crypt_stat->num_header_extents_at_front);
- ecryptfs_printk(KERN_DEBUG, " * extents_occupied_by_headers_at_"
- "front = [%d]\n", extents_occupied_by_headers_at_front);
- ecryptfs_printk(KERN_DEBUG, " * lower_extent_num = [0x%.16x]\n",
- lower_extent_num);
- ecryptfs_printk(KERN_DEBUG, " * extents_per_page = [%d]\n",
- extents_per_page);
- ecryptfs_printk(KERN_DEBUG, " * (*lower_page_idx) = [0x%.16x]\n",
- (*lower_page_idx));
- ecryptfs_printk(KERN_DEBUG, " * extent_offset = [%d]\n",
- extent_offset);
- ecryptfs_printk(KERN_DEBUG, " * (*byte_offset) = [%d]\n",
- (*byte_offset));
+ (*offset) = (crypt_stat->num_header_bytes_at_front
+ + (crypt_stat->extent_size * extent_num));
}
-static int ecryptfs_write_out_page(struct ecryptfs_page_crypt_context *ctx,
- struct page *lower_page,
- struct inode *lower_inode,
- int byte_offset_in_page, int bytes_to_write)
+/**
+ * ecryptfs_encrypt_extent
+ * @enc_extent_page: Allocated page into which to encrypt the data in
+ * @page
+ * @crypt_stat: crypt_stat containing cryptographic context for the
+ * encryption operation
+ * @page: Page containing plaintext data extent to encrypt
+ * @extent_offset: Page extent offset for use in generating IV
+ *
+ * Encrypts 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)
{
- int rc = 0;
+ loff_t extent_base;
+ char extent_iv[ECRYPTFS_MAX_IV_BYTES];
+ int rc;
- if (ctx->mode == ECRYPTFS_PREPARE_COMMIT_MODE) {
- rc = ecryptfs_commit_lower_page(lower_page, lower_inode,
- ctx->param.lower_file,
- byte_offset_in_page,
- bytes_to_write);
- if (rc) {
- ecryptfs_printk(KERN_ERR, "Error calling lower "
- "commit; rc = [%d]\n", rc);
- goto out;
- }
- } else {
- rc = ecryptfs_writepage_and_release_lower_page(lower_page,
- lower_inode,
- ctx->param.wbc);
- if (rc) {
- ecryptfs_printk(KERN_ERR, "Error calling lower "
- "writepage(); rc = [%d]\n", rc);
- goto out;
- }
+ 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%.16x]; "
+ "rc = [%d]\n", (extent_base + extent_offset),
+ rc);
+ goto out;
}
-out:
- return rc;
-}
-
-static int ecryptfs_read_in_page(struct ecryptfs_page_crypt_context *ctx,
- struct page **lower_page,
- struct inode *lower_inode,
- unsigned long lower_page_idx,
- int byte_offset_in_page)
-{
- int rc = 0;
-
- if (ctx->mode == ECRYPTFS_PREPARE_COMMIT_MODE) {
- /* TODO: Limit this to only the data extents that are
- * needed */
- rc = ecryptfs_get_lower_page(lower_page, lower_inode,
- ctx->param.lower_file,
- lower_page_idx,
- byte_offset_in_page,
- (PAGE_CACHE_SIZE
- - byte_offset_in_page));
- if (rc) {
- ecryptfs_printk(
- KERN_ERR, "Error attempting to grab, map, "
- "and prepare_write lower page with index "
- "[0x%.16x]; rc = [%d]\n", lower_page_idx, rc);
- goto out;
- }
- } else {
- rc = ecryptfs_grab_and_map_lower_page(lower_page, NULL,
- lower_inode,
- lower_page_idx);
- if (rc) {
- ecryptfs_printk(
- KERN_ERR, "Error attempting to grab and map "
- "lower page with index [0x%.16x]; rc = [%d]\n",
- lower_page_idx, rc);
- goto out;
- }
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "Encrypting extent "
+ "with iv:\n");
+ ecryptfs_dump_hex(extent_iv, crypt_stat->iv_bytes);
+ ecryptfs_printk(KERN_DEBUG, "First 8 bytes before "
+ "encryption:\n");
+ ecryptfs_dump_hex((char *)
+ (page_address(page)
+ + (extent_offset * crypt_stat->extent_size)),
+ 8);
+ }
+ rc = ecryptfs_encrypt_page_offset(crypt_stat, enc_extent_page, 0,
+ page, (extent_offset
+ * crypt_stat->extent_size),
+ crypt_stat->extent_size, extent_iv);
+ 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);
+ goto out;
+ }
+ rc = 0;
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "Encrypt extent [0x%.16x]; "
+ "rc = [%d]\n", (extent_base + extent_offset),
+ rc);
+ ecryptfs_printk(KERN_DEBUG, "First 8 bytes after "
+ "encryption:\n");
+ ecryptfs_dump_hex((char *)(page_address(enc_extent_page)), 8);
}
out:
return rc;
/**
* ecryptfs_encrypt_page
- * @ctx: The context of the page
+ * @page: Page mapped from the eCryptfs inode for the file; contains
+ * decrypted content that needs to be encrypted (to a temporary
+ * page; not in place) and written out to the lower file
*
* Encrypt an eCryptfs page. This is done on a per-extent basis. Note
* that eCryptfs pages may straddle the lower pages -- for instance,
* file, 24K of page 0 of the lower file will be read and decrypted,
* and then 8K of page 1 of the lower file will be read and decrypted.
*
- * The actual operations performed on each page depends on the
- * contents of the ecryptfs_page_crypt_context struct.
- *
* Returns zero on success; negative on error
*/
-int ecryptfs_encrypt_page(struct ecryptfs_page_crypt_context *ctx)
+int ecryptfs_encrypt_page(struct page *page)
{
- char extent_iv[ECRYPTFS_MAX_IV_BYTES];
- unsigned long base_extent;
- unsigned long extent_offset = 0;
- unsigned long lower_page_idx = 0;
- unsigned long prior_lower_page_idx = 0;
- struct page *lower_page;
- struct inode *lower_inode;
- struct ecryptfs_inode_info *inode_info;
+ struct inode *ecryptfs_inode;
struct ecryptfs_crypt_stat *crypt_stat;
+ char *enc_extent_virt;
+ struct page *enc_extent_page = NULL;
+ loff_t extent_offset;
int rc = 0;
- int lower_byte_offset = 0;
- int orig_byte_offset = 0;
- int num_extents_per_page;
-#define ECRYPTFS_PAGE_STATE_UNREAD 0
-#define ECRYPTFS_PAGE_STATE_READ 1
-#define ECRYPTFS_PAGE_STATE_MODIFIED 2
-#define ECRYPTFS_PAGE_STATE_WRITTEN 3
- int page_state;
-
- lower_inode = ecryptfs_inode_to_lower(ctx->page->mapping->host);
- inode_info = ecryptfs_inode_to_private(ctx->page->mapping->host);
- crypt_stat = &inode_info->crypt_stat;
- if (!ECRYPTFS_CHECK_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED)) {
- rc = ecryptfs_copy_page_to_lower(ctx->page, lower_inode,
- ctx->param.lower_file);
- if (rc)
- ecryptfs_printk(KERN_ERR, "Error attempting to copy "
- "page at index [0x%.16x]\n",
- ctx->page->index);
+
+ 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");
goto out;
}
- num_extents_per_page = PAGE_CACHE_SIZE / crypt_stat->extent_size;
- base_extent = (ctx->page->index * num_extents_per_page);
- page_state = ECRYPTFS_PAGE_STATE_UNREAD;
- while (extent_offset < num_extents_per_page) {
- ecryptfs_extent_to_lwr_pg_idx_and_offset(
- &lower_page_idx, &lower_byte_offset, crypt_stat,
- (base_extent + extent_offset));
- if (prior_lower_page_idx != lower_page_idx
- && page_state == ECRYPTFS_PAGE_STATE_MODIFIED) {
- rc = ecryptfs_write_out_page(ctx, lower_page,
- lower_inode,
- orig_byte_offset,
- (PAGE_CACHE_SIZE
- - orig_byte_offset));
- if (rc) {
- ecryptfs_printk(KERN_ERR, "Error attempting "
- "to write out page; rc = [%d]"
- "\n", rc);
- goto out;
- }
- page_state = ECRYPTFS_PAGE_STATE_WRITTEN;
- }
- if (page_state == ECRYPTFS_PAGE_STATE_UNREAD
- || page_state == ECRYPTFS_PAGE_STATE_WRITTEN) {
- rc = ecryptfs_read_in_page(ctx, &lower_page,
- lower_inode, lower_page_idx,
- lower_byte_offset);
- if (rc) {
- ecryptfs_printk(KERN_ERR, "Error attempting "
- "to read in lower page with "
- "index [0x%.16x]; rc = [%d]\n",
- lower_page_idx, rc);
- goto out;
- }
- orig_byte_offset = lower_byte_offset;
- prior_lower_page_idx = lower_page_idx;
- page_state = ECRYPTFS_PAGE_STATE_READ;
- }
- BUG_ON(!(page_state == ECRYPTFS_PAGE_STATE_MODIFIED
- || page_state == ECRYPTFS_PAGE_STATE_READ));
- rc = ecryptfs_derive_iv(extent_iv, crypt_stat,
- (base_extent + extent_offset));
+ 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);
if (rc) {
- ecryptfs_printk(KERN_ERR, "Error attempting to "
- "derive IV for extent [0x%.16x]; "
- "rc = [%d]\n",
- (base_extent + extent_offset), rc);
+ printk(KERN_ERR "%s: Error encrypting extent; "
+ "rc = [%d]\n", __func__, rc);
goto out;
}
- if (unlikely(ecryptfs_verbosity > 0)) {
- ecryptfs_printk(KERN_DEBUG, "Encrypting extent "
- "with iv:\n");
- ecryptfs_dump_hex(extent_iv, crypt_stat->iv_bytes);
- ecryptfs_printk(KERN_DEBUG, "First 8 bytes before "
- "encryption:\n");
- ecryptfs_dump_hex((char *)
- (page_address(ctx->page)
- + (extent_offset
- * crypt_stat->extent_size)), 8);
- }
- rc = ecryptfs_encrypt_page_offset(
- crypt_stat, lower_page, lower_byte_offset, ctx->page,
- (extent_offset * crypt_stat->extent_size),
- crypt_stat->extent_size, extent_iv);
- ecryptfs_printk(KERN_DEBUG, "Encrypt extent [0x%.16x]; "
- "rc = [%d]\n",
- (base_extent + extent_offset), rc);
- if (unlikely(ecryptfs_verbosity > 0)) {
- ecryptfs_printk(KERN_DEBUG, "First 8 bytes after "
- "encryption:\n");
- ecryptfs_dump_hex((char *)(page_address(lower_page)
- + lower_byte_offset), 8);
+ 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;
}
- page_state = ECRYPTFS_PAGE_STATE_MODIFIED;
- extent_offset++;
}
- BUG_ON(orig_byte_offset != 0);
- rc = ecryptfs_write_out_page(ctx, lower_page, lower_inode, 0,
- (lower_byte_offset
- + crypt_stat->extent_size));
+ 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 write out "
- "page; rc = [%d]\n", rc);
- goto out;
+ ecryptfs_printk(KERN_ERR, "Error attempting to "
+ "derive IV for extent [0x%.16x]; "
+ "rc = [%d]\n", (extent_base + extent_offset),
+ rc);
+ goto out;
+ }
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "Decrypting extent "
+ "with iv:\n");
+ ecryptfs_dump_hex(extent_iv, crypt_stat->iv_bytes);
+ ecryptfs_printk(KERN_DEBUG, "First 8 bytes before "
+ "decryption:\n");
+ ecryptfs_dump_hex((char *)
+ (page_address(enc_extent_page)
+ + (extent_offset * crypt_stat->extent_size)),
+ 8);
+ }
+ rc = ecryptfs_decrypt_page_offset(crypt_stat, page,
+ (extent_offset
+ * crypt_stat->extent_size),
+ enc_extent_page, 0,
+ crypt_stat->extent_size, extent_iv);
+ 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);
+ goto out;
+ }
+ rc = 0;
+ if (unlikely(ecryptfs_verbosity > 0)) {
+ ecryptfs_printk(KERN_DEBUG, "Decrypt extent [0x%.16x]; "
+ "rc = [%d]\n", (extent_base + extent_offset),
+ rc);
+ ecryptfs_printk(KERN_DEBUG, "First 8 bytes after "
+ "decryption:\n");
+ ecryptfs_dump_hex((char *)(page_address(page)
+ + (extent_offset
+ * crypt_stat->extent_size)), 8);
}
out:
return rc;
/**
* ecryptfs_decrypt_page
- * @file: The ecryptfs file
- * @page: The page in ecryptfs to decrypt
+ * @page: Page mapped from the eCryptfs inode for the file; data read
+ * and decrypted from the lower file will be written into this
+ * page
*
* Decrypt an eCryptfs page. This is done on a per-extent basis. Note
* that eCryptfs pages may straddle the lower pages -- for instance,
*
* Returns zero on success; negative on error
*/
-int ecryptfs_decrypt_page(struct file *file, struct page *page)
+int ecryptfs_decrypt_page(struct page *page)
{
- char extent_iv[ECRYPTFS_MAX_IV_BYTES];
- unsigned long base_extent;
- unsigned long extent_offset = 0;
- unsigned long lower_page_idx = 0;
- unsigned long prior_lower_page_idx = 0;
- struct page *lower_page;
- char *lower_page_virt = NULL;
- struct inode *lower_inode;
+ struct inode *ecryptfs_inode;
struct ecryptfs_crypt_stat *crypt_stat;
+ char *enc_extent_virt;
+ struct page *enc_extent_page = NULL;
+ unsigned long extent_offset;
int rc = 0;
- int byte_offset;
- int num_extents_per_page;
- int page_state;
-
- crypt_stat = &(ecryptfs_inode_to_private(
- page->mapping->host)->crypt_stat);
- lower_inode = ecryptfs_inode_to_lower(page->mapping->host);
- if (!ECRYPTFS_CHECK_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED)) {
- rc = ecryptfs_do_readpage(file, page, page->index);
- if (rc)
- ecryptfs_printk(KERN_ERR, "Error attempting to copy "
- "page at index [0x%.16x]\n",
- page->index);
- goto out;
- }
- num_extents_per_page = PAGE_CACHE_SIZE / crypt_stat->extent_size;
- base_extent = (page->index * num_extents_per_page);
- lower_page_virt = kmem_cache_alloc(ecryptfs_lower_page_cache,
- SLAB_KERNEL);
- if (!lower_page_virt) {
+
+ 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 getting page for encrypted "
- "lower page(s)\n");
+ ecryptfs_printk(KERN_ERR, "Error allocating memory for "
+ "encrypted extent\n");
goto out;
}
- lower_page = virt_to_page(lower_page_virt);
- page_state = ECRYPTFS_PAGE_STATE_UNREAD;
- while (extent_offset < num_extents_per_page) {
- ecryptfs_extent_to_lwr_pg_idx_and_offset(
- &lower_page_idx, &byte_offset, crypt_stat,
- (base_extent + extent_offset));
- if (prior_lower_page_idx != lower_page_idx
- || page_state == ECRYPTFS_PAGE_STATE_UNREAD) {
- rc = ecryptfs_do_readpage(file, lower_page,
- lower_page_idx);
- if (rc) {
- ecryptfs_printk(KERN_ERR, "Error reading "
- "lower encrypted page; rc = "
- "[%d]\n", rc);
- goto out;
- }
- prior_lower_page_idx = lower_page_idx;
- page_state = ECRYPTFS_PAGE_STATE_READ;
- }
- rc = ecryptfs_derive_iv(extent_iv, crypt_stat,
- (base_extent + extent_offset));
- if (rc) {
- ecryptfs_printk(KERN_ERR, "Error attempting to "
- "derive IV for extent [0x%.16x]; rc = "
- "[%d]\n",
- (base_extent + extent_offset), rc);
+ 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;
}
- if (unlikely(ecryptfs_verbosity > 0)) {
- ecryptfs_printk(KERN_DEBUG, "Decrypting extent "
- "with iv:\n");
- ecryptfs_dump_hex(extent_iv, crypt_stat->iv_bytes);
- ecryptfs_printk(KERN_DEBUG, "First 8 bytes before "
- "decryption:\n");
- ecryptfs_dump_hex((lower_page_virt + byte_offset), 8);
- }
- rc = ecryptfs_decrypt_page_offset(crypt_stat, page,
- (extent_offset
- * crypt_stat->extent_size),
- lower_page, byte_offset,
- crypt_stat->extent_size,
- extent_iv);
- if (rc != crypt_stat->extent_size) {
- ecryptfs_printk(KERN_ERR, "Error attempting to "
- "decrypt extent [0x%.16x]\n",
- (base_extent + extent_offset));
+ rc = ecryptfs_decrypt_extent(page, crypt_stat, enc_extent_page,
+ extent_offset);
+ if (rc) {
+ printk(KERN_ERR "%s: Error encrypting extent; "
+ "rc = [%d]\n", __func__, rc);
goto out;
}
- rc = 0;
- if (unlikely(ecryptfs_verbosity > 0)) {
- ecryptfs_printk(KERN_DEBUG, "First 8 bytes after "
- "decryption:\n");
- ecryptfs_dump_hex((char *)(page_address(page)
- + byte_offset), 8);
- }
- extent_offset++;
}
out:
- if (lower_page_virt)
- kmem_cache_free(ecryptfs_lower_page_cache, lower_page_virt);
+ 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
*/
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);
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",
/**
* 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
*/
{
struct scatterlist src_sg, dst_sg;
- src_sg.page = src_page;
- src_sg.offset = src_offset;
- src_sg.length = size;
- dst_sg.page = dst_page;
- dst_sg.offset = dst_offset;
- dst_sg.length = size;
+ 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
*/
{
struct scatterlist src_sg, dst_sg;
- src_sg.page = src_page;
- src_sg.offset = src_offset;
- src_sg.length = size;
- dst_sg.page = dst_page;
- dst_sg.offset = dst_offset;
- dst_sg.length = size;
+ 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);
}
*/
int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat)
{
+ char *full_alg_name;
int rc = -EINVAL;
if (!crypt_stat->cipher) {
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);
- if (!crypt_stat->tfm) {
+ rc = ecryptfs_crypto_api_algify_cipher_name(&full_alg_name,
+ crypt_stat->cipher, "cbc");
+ if (rc)
+ goto out_unlock;
+ crypt_stat->tfm = crypto_alloc_blkcipher(full_alg_name, 0,
+ CRYPTO_ALG_ASYNC);
+ kfree(full_alg_name);
+ if (IS_ERR(crypt_stat->tfm)) {
+ rc = PTR_ERR(crypt_stat->tfm);
+ crypt_stat->tfm = NULL;
ecryptfs_printk(KERN_ERR, "cryptfs: init_crypt_ctx(): "
"Error initializing cipher [%s]\n",
crypt_stat->cipher);
- goto out;
+ goto out_unlock;
}
+ crypto_blkcipher_set_flags(crypt_stat->tfm, CRYPTO_TFM_REQ_WEAK_KEY);
rc = 0;
+out_unlock:
+ mutex_unlock(&crypt_stat->cs_tfm_mutex);
out:
return rc;
}
crypt_stat->extent_size = ECRYPTFS_DEFAULT_EXTENT_SIZE;
set_extent_mask_and_shift(crypt_stat);
crypt_stat->iv_bytes = ECRYPTFS_DEFAULT_IV_BYTES;
- if (PAGE_CACHE_SIZE <= ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE) {
- crypt_stat->header_extent_size =
- ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE;
- } else
- crypt_stat->header_extent_size = PAGE_CACHE_SIZE;
- crypt_stat->num_header_extents_at_front = 1;
+ if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
+ crypt_stat->num_header_bytes_at_front = 0;
+ else {
+ if (PAGE_CACHE_SIZE <= ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE)
+ crypt_stat->num_header_bytes_at_front =
+ ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE;
+ else
+ crypt_stat->num_header_bytes_at_front = PAGE_CACHE_SIZE;
+ }
}
/**
BUG_ON(crypt_stat->iv_bytes > MD5_DIGEST_SIZE);
BUG_ON(crypt_stat->iv_bytes <= 0);
- if (!ECRYPTFS_CHECK_FLAG(crypt_stat->flags, ECRYPTFS_KEY_VALID)) {
+ if (!(crypt_stat->flags & ECRYPTFS_KEY_VALID)) {
rc = -EINVAL;
ecryptfs_printk(KERN_WARNING, "Session key not valid; "
"cannot generate root IV\n");
out:
if (rc) {
memset(crypt_stat->root_iv, 0, crypt_stat->iv_bytes);
- ECRYPTFS_SET_FLAG(crypt_stat->flags,
- ECRYPTFS_SECURITY_WARNING);
+ crypt_stat->flags |= ECRYPTFS_SECURITY_WARNING;
}
return rc;
}
static void ecryptfs_generate_new_key(struct ecryptfs_crypt_stat *crypt_stat)
{
get_random_bytes(crypt_stat->key, crypt_stat->key_size);
- ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_KEY_VALID);
+ crypt_stat->flags |= ECRYPTFS_KEY_VALID;
ecryptfs_compute_root_iv(crypt_stat);
if (unlikely(ecryptfs_verbosity > 0)) {
ecryptfs_printk(KERN_DEBUG, "Generated new session key:\n");
}
/**
+ * ecryptfs_copy_mount_wide_flags_to_inode_flags
+ * @crypt_stat: The inode's cryptographic context
+ * @mount_crypt_stat: The mount point's cryptographic context
+ *
+ * This function propagates the mount-wide flags to individual inode
+ * flags.
+ */
+static void ecryptfs_copy_mount_wide_flags_to_inode_flags(
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
+{
+ if (mount_crypt_stat->flags & ECRYPTFS_XATTR_METADATA_ENABLED)
+ crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
+ if (mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED)
+ crypt_stat->flags |= ECRYPTFS_VIEW_AS_ENCRYPTED;
+ if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
+ crypt_stat->flags |= ECRYPTFS_ENCRYPT_FILENAMES;
+ if (mount_crypt_stat->flags
+ & ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK)
+ crypt_stat->flags |= ECRYPTFS_ENCFN_USE_MOUNT_FNEK;
+ else if (mount_crypt_stat->flags
+ & ECRYPTFS_GLOBAL_ENCFN_USE_FEK)
+ crypt_stat->flags |= ECRYPTFS_ENCFN_USE_FEK;
+ }
+}
+
+static int ecryptfs_copy_mount_wide_sigs_to_inode_sigs(
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
+{
+ struct ecryptfs_global_auth_tok *global_auth_tok;
+ int rc = 0;
+
+ mutex_lock(&crypt_stat->keysig_list_mutex);
+ mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex);
+
+ list_for_each_entry(global_auth_tok,
+ &mount_crypt_stat->global_auth_tok_list,
+ mount_crypt_stat_list) {
+ if (global_auth_tok->flags & ECRYPTFS_AUTH_TOK_FNEK)
+ continue;
+ rc = ecryptfs_add_keysig(crypt_stat, global_auth_tok->sig);
+ if (rc) {
+ printk(KERN_ERR "Error adding keysig; rc = [%d]\n", rc);
+ goto out;
+ }
+ }
+
+out:
+ mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex);
+ mutex_unlock(&crypt_stat->keysig_list_mutex);
+ return rc;
+}
+
+/**
* ecryptfs_set_default_crypt_stat_vals
- * @crypt_stat
+ * @crypt_stat: The inode's cryptographic context
+ * @mount_crypt_stat: The mount point's cryptographic context
*
* Default values in the event that policy does not override them.
*/
struct ecryptfs_crypt_stat *crypt_stat,
struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
{
+ ecryptfs_copy_mount_wide_flags_to_inode_flags(crypt_stat,
+ mount_crypt_stat);
ecryptfs_set_default_sizes(crypt_stat);
strcpy(crypt_stat->cipher, ECRYPTFS_DEFAULT_CIPHER);
crypt_stat->key_size = ECRYPTFS_DEFAULT_KEY_BYTES;
- ECRYPTFS_CLEAR_FLAG(crypt_stat->flags, ECRYPTFS_KEY_VALID);
+ crypt_stat->flags &= ~(ECRYPTFS_KEY_VALID);
crypt_stat->file_version = ECRYPTFS_FILE_VERSION;
crypt_stat->mount_crypt_stat = mount_crypt_stat;
}
/**
* ecryptfs_new_file_context
- * @ecryptfs_dentry
+ * @ecryptfs_dentry: The eCryptfs dentry
*
* If the crypto context for the file has not yet been established,
* this is where we do that. Establishing a new crypto context
*
* Returns zero on success; non-zero otherwise
*/
-/* Associate an authentication token(s) with the file */
int ecryptfs_new_file_context(struct dentry *ecryptfs_dentry)
{
- int rc = 0;
struct ecryptfs_crypt_stat *crypt_stat =
&ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat;
struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
&ecryptfs_superblock_to_private(
ecryptfs_dentry->d_sb)->mount_crypt_stat;
int cipher_name_len;
+ int rc = 0;
ecryptfs_set_default_crypt_stat_vals(crypt_stat, mount_crypt_stat);
- /* See if there are mount crypt options */
- if (mount_crypt_stat->global_auth_tok) {
- ecryptfs_printk(KERN_DEBUG, "Initializing context for new "
- "file using mount_crypt_stat\n");
- ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED);
- ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_KEY_VALID);
- memcpy(crypt_stat->keysigs[crypt_stat->num_keysigs++],
- mount_crypt_stat->global_auth_tok_sig,
- ECRYPTFS_SIG_SIZE_HEX);
- cipher_name_len =
- strlen(mount_crypt_stat->global_default_cipher_name);
- memcpy(crypt_stat->cipher,
- mount_crypt_stat->global_default_cipher_name,
- cipher_name_len);
- crypt_stat->cipher[cipher_name_len] = '\0';
- crypt_stat->key_size =
- mount_crypt_stat->global_default_cipher_key_size;
- ecryptfs_generate_new_key(crypt_stat);
- } else
- /* We should not encounter this scenario since we
- * should detect lack of global_auth_tok at mount time
- * TODO: Applies to 0.1 release only; remove in future
- * release */
- BUG();
+ crypt_stat->flags |= (ECRYPTFS_ENCRYPTED | ECRYPTFS_KEY_VALID);
+ ecryptfs_copy_mount_wide_flags_to_inode_flags(crypt_stat,
+ mount_crypt_stat);
+ rc = ecryptfs_copy_mount_wide_sigs_to_inode_sigs(crypt_stat,
+ mount_crypt_stat);
+ if (rc) {
+ printk(KERN_ERR "Error attempting to copy mount-wide key sigs "
+ "to the inode key sigs; rc = [%d]\n", rc);
+ goto out;
+ }
+ cipher_name_len =
+ strlen(mount_crypt_stat->global_default_cipher_name);
+ memcpy(crypt_stat->cipher,
+ mount_crypt_stat->global_default_cipher_name,
+ cipher_name_len);
+ crypt_stat->cipher[cipher_name_len] = '\0';
+ crypt_stat->key_size =
+ mount_crypt_stat->global_default_cipher_key_size;
+ ecryptfs_generate_new_key(crypt_stat);
rc = ecryptfs_init_crypt_ctx(crypt_stat);
if (rc)
ecryptfs_printk(KERN_ERR, "Error initializing cryptographic "
"context for cipher [%s]: rc = [%d]\n",
crypt_stat->cipher, rc);
+out:
return rc;
}
*
* Returns one if marker found; zero if not found
*/
-int contains_ecryptfs_marker(char *data)
+static int contains_ecryptfs_marker(char *data)
{
u32 m_1, m_2;
- memcpy(&m_1, data, 4);
- m_1 = be32_to_cpu(m_1);
- memcpy(&m_2, (data + 4), 4);
- m_2 = be32_to_cpu(m_2);
+ m_1 = get_unaligned_be32(data);
+ m_2 = get_unaligned_be32(data + 4);
if ((m_1 ^ MAGIC_ECRYPTFS_MARKER) == m_2)
return 1;
ecryptfs_printk(KERN_DEBUG, "m_1 = [0x%.8x]; m_2 = [0x%.8x]; "
/* Add support for additional flags by adding elements here. */
static struct ecryptfs_flag_map_elem ecryptfs_flag_map[] = {
{0x00000001, ECRYPTFS_ENABLE_HMAC},
- {0x00000002, ECRYPTFS_ENCRYPTED}
+ {0x00000002, ECRYPTFS_ENCRYPTED},
+ {0x00000004, ECRYPTFS_METADATA_IN_XATTR},
+ {0x00000008, ECRYPTFS_ENCRYPT_FILENAMES}
};
/**
* ecryptfs_process_flags
- * @crypt_stat
+ * @crypt_stat: The cryptographic context
* @page_virt: Source data to be parsed
* @bytes_read: Updated with the number of bytes read
*
int i;
u32 flags;
- memcpy(&flags, page_virt, 4);
- flags = be32_to_cpu(flags);
+ flags = get_unaligned_be32(page_virt);
for (i = 0; i < ((sizeof(ecryptfs_flag_map)
/ sizeof(struct ecryptfs_flag_map_elem))); i++)
if (flags & ecryptfs_flag_map[i].file_flag) {
- ECRYPTFS_SET_FLAG(crypt_stat->flags,
- ecryptfs_flag_map[i].local_flag);
+ crypt_stat->flags |= ecryptfs_flag_map[i].local_flag;
} else
- ECRYPTFS_CLEAR_FLAG(crypt_stat->flags,
- ecryptfs_flag_map[i].local_flag);
+ crypt_stat->flags &= ~(ecryptfs_flag_map[i].local_flag);
/* Version is in top 8 bits of the 32-bit flag vector */
crypt_stat->file_version = ((flags >> 24) & 0xFF);
(*bytes_read) = 4;
get_random_bytes(&m_1, (MAGIC_ECRYPTFS_MARKER_SIZE_BYTES / 2));
m_2 = (m_1 ^ MAGIC_ECRYPTFS_MARKER);
- m_1 = cpu_to_be32(m_1);
- memcpy(page_virt, &m_1, (MAGIC_ECRYPTFS_MARKER_SIZE_BYTES / 2));
- m_2 = cpu_to_be32(m_2);
- memcpy(page_virt + (MAGIC_ECRYPTFS_MARKER_SIZE_BYTES / 2), &m_2,
- (MAGIC_ECRYPTFS_MARKER_SIZE_BYTES / 2));
+ put_unaligned_be32(m_1, page_virt);
+ page_virt += (MAGIC_ECRYPTFS_MARKER_SIZE_BYTES / 2);
+ put_unaligned_be32(m_2, page_virt);
(*written) = MAGIC_ECRYPTFS_MARKER_SIZE_BYTES;
}
for (i = 0; i < ((sizeof(ecryptfs_flag_map)
/ sizeof(struct ecryptfs_flag_map_elem))); i++)
- if (ECRYPTFS_CHECK_FLAG(crypt_stat->flags,
- ecryptfs_flag_map[i].local_flag))
+ if (crypt_stat->flags & ecryptfs_flag_map[i].local_flag)
flags |= ecryptfs_flag_map[i].file_flag;
/* Version is in top 8 bits of the 32-bit flag vector */
flags |= ((((u8)crypt_stat->file_version) << 24) & 0xFF000000);
- flags = cpu_to_be32(flags);
- memcpy(page_virt, &flags, 4);
+ put_unaligned_be32(flags, page_virt);
(*written) = 4;
}
struct ecryptfs_cipher_code_str_map_elem {
char cipher_str[16];
- u16 cipher_code;
+ u8 cipher_code;
};
/* Add support for additional ciphers by adding elements here. The
/**
* ecryptfs_code_for_cipher_string
- * @str: The string representing the cipher name
+ * @cipher_name: The string alias for the cipher
+ * @key_bytes: Length of key in bytes; used for AES code selection
*
* Returns zero on no match, or the cipher code on match
*/
-u16 ecryptfs_code_for_cipher_string(struct ecryptfs_crypt_stat *crypt_stat)
+u8 ecryptfs_code_for_cipher_string(char *cipher_name, size_t key_bytes)
{
int i;
- u16 code = 0;
+ u8 code = 0;
struct ecryptfs_cipher_code_str_map_elem *map =
ecryptfs_cipher_code_str_map;
- if (strcmp(crypt_stat->cipher, "aes") == 0) {
- switch (crypt_stat->key_size) {
+ if (strcmp(cipher_name, "aes") == 0) {
+ switch (key_bytes) {
case 16:
code = RFC2440_CIPHER_AES_128;
break;
}
} else {
for (i = 0; i < ARRAY_SIZE(ecryptfs_cipher_code_str_map); i++)
- if (strcmp(crypt_stat->cipher, map[i].cipher_str) == 0){
+ if (strcmp(cipher_name, map[i].cipher_str) == 0) {
code = map[i].cipher_code;
break;
}
*
* Returns zero on success
*/
-int ecryptfs_cipher_code_to_string(char *str, u16 cipher_code)
+int ecryptfs_cipher_code_to_string(char *str, u8 cipher_code)
{
int rc = 0;
int i;
return rc;
}
-/**
- * ecryptfs_read_header_region
- * @data
- * @dentry
- * @nd
- *
- * Returns zero on success; non-zero otherwise
- */
-int ecryptfs_read_header_region(char *data, struct dentry *dentry,
- struct vfsmount *mnt)
+int ecryptfs_read_and_validate_header_region(char *data,
+ struct inode *ecryptfs_inode)
{
- struct file *file;
- mm_segment_t oldfs;
+ struct ecryptfs_crypt_stat *crypt_stat =
+ &(ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat);
int rc;
- mnt = mntget(mnt);
- file = dentry_open(dentry, mnt, O_RDONLY);
- if (IS_ERR(file)) {
- ecryptfs_printk(KERN_DEBUG, "Error opening file to "
- "read header region\n");
- mntput(mnt);
- rc = PTR_ERR(file);
+ if (crypt_stat->extent_size == 0)
+ crypt_stat->extent_size = ECRYPTFS_DEFAULT_EXTENT_SIZE;
+ rc = ecryptfs_read_lower(data, 0, crypt_stat->extent_size,
+ ecryptfs_inode);
+ if (rc < 0) {
+ printk(KERN_ERR "%s: Error reading header region; rc = [%d]\n",
+ __func__, rc);
goto out;
}
- file->f_pos = 0;
- oldfs = get_fs();
- set_fs(get_ds());
- /* For releases 0.1 and 0.2, all of the header information
- * fits in the first data extent-sized region. */
- rc = file->f_op->read(file, (char __user *)data,
- ECRYPTFS_DEFAULT_EXTENT_SIZE, &file->f_pos);
- set_fs(oldfs);
- fput(file);
- rc = 0;
+ if (!contains_ecryptfs_marker(data + ECRYPTFS_FILE_SIZE_BYTES)) {
+ rc = -EINVAL;
+ } else
+ rc = 0;
out:
return rc;
}
-static void
-write_header_metadata(char *virt, struct ecryptfs_crypt_stat *crypt_stat,
- size_t *written)
+void
+ecryptfs_write_header_metadata(char *virt,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ size_t *written)
{
u32 header_extent_size;
u16 num_header_extents_at_front;
- header_extent_size = (u32)crypt_stat->header_extent_size;
+ header_extent_size = (u32)crypt_stat->extent_size;
num_header_extents_at_front =
- (u16)crypt_stat->num_header_extents_at_front;
- header_extent_size = cpu_to_be32(header_extent_size);
- memcpy(virt, &header_extent_size, 4);
+ (u16)(crypt_stat->num_header_bytes_at_front
+ / crypt_stat->extent_size);
+ put_unaligned_be32(header_extent_size, virt);
virt += 4;
- num_header_extents_at_front = cpu_to_be16(num_header_extents_at_front);
- memcpy(virt, &num_header_extents_at_front, 2);
+ put_unaligned_be16(num_header_extents_at_front, virt);
(*written) = 6;
}
-struct kmem_cache *ecryptfs_header_cache_0;
struct kmem_cache *ecryptfs_header_cache_1;
struct kmem_cache *ecryptfs_header_cache_2;
/**
* ecryptfs_write_headers_virt
- * @page_virt
- * @crypt_stat
- * @ecryptfs_dentry
+ * @page_virt: The virtual address to write the headers to
+ * @max: The size of memory allocated at page_virt
+ * @size: Set to the number of bytes written by this function
+ * @crypt_stat: The cryptographic context
+ * @ecryptfs_dentry: The eCryptfs dentry
*
* Format version: 1
*
*
* Returns zero on success
*/
-int ecryptfs_write_headers_virt(char *page_virt,
- struct ecryptfs_crypt_stat *crypt_stat,
- struct dentry *ecryptfs_dentry)
+static int ecryptfs_write_headers_virt(char *page_virt, size_t max,
+ size_t *size,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct dentry *ecryptfs_dentry)
{
int rc;
size_t written;
offset += written;
write_ecryptfs_flags((page_virt + offset), crypt_stat, &written);
offset += written;
- write_header_metadata((page_virt + offset), crypt_stat, &written);
+ ecryptfs_write_header_metadata((page_virt + offset), crypt_stat,
+ &written);
offset += written;
rc = ecryptfs_generate_key_packet_set((page_virt + offset), crypt_stat,
ecryptfs_dentry, &written,
- PAGE_CACHE_SIZE - offset);
+ max - offset);
if (rc)
ecryptfs_printk(KERN_WARNING, "Error generating key packet "
"set; rc = [%d]\n", rc);
+ if (size) {
+ offset += written;
+ *size = offset;
+ }
+ return rc;
+}
+
+static int
+ecryptfs_write_metadata_to_contents(struct dentry *ecryptfs_dentry,
+ char *virt, size_t virt_len)
+{
+ int rc;
+
+ rc = ecryptfs_write_lower(ecryptfs_dentry->d_inode, virt,
+ 0, virt_len);
+ if (rc < 0)
+ printk(KERN_ERR "%s: Error attempting to write header "
+ "information to lower file; rc = [%d]\n", __func__, rc);
+ else
+ rc = 0;
+ return rc;
+}
+
+static int
+ecryptfs_write_metadata_to_xattr(struct dentry *ecryptfs_dentry,
+ char *page_virt, size_t size)
+{
+ int rc;
+
+ rc = ecryptfs_setxattr(ecryptfs_dentry, ECRYPTFS_XATTR_NAME, page_virt,
+ size, 0);
return rc;
}
+static unsigned long ecryptfs_get_zeroed_pages(gfp_t gfp_mask,
+ unsigned int order)
+{
+ struct page *page;
+
+ page = alloc_pages(gfp_mask | __GFP_ZERO, order);
+ if (page)
+ return (unsigned long) page_address(page);
+ return 0;
+}
+
/**
- * ecryptfs_write_headers
- * @lower_file: The lower file struct, which was returned from dentry_open
+ * ecryptfs_write_metadata
+ * @ecryptfs_dentry: The eCryptfs dentry
*
* Write the file headers out. This will likely involve a userspace
* callout, in which the session key is encrypted with one or more
*
* Returns zero on success; non-zero on error
*/
-int ecryptfs_write_headers(struct dentry *ecryptfs_dentry,
- struct file *lower_file)
+int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry)
{
- mm_segment_t oldfs;
- struct ecryptfs_crypt_stat *crypt_stat;
- char *page_virt;
- int current_header_page;
- int header_pages;
+ struct ecryptfs_crypt_stat *crypt_stat =
+ &ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat;
+ unsigned int order;
+ char *virt;
+ size_t virt_len;
+ size_t size = 0;
int rc = 0;
- crypt_stat = &ecryptfs_inode_to_private(
- ecryptfs_dentry->d_inode)->crypt_stat;
- if (likely(ECRYPTFS_CHECK_FLAG(crypt_stat->flags,
- ECRYPTFS_ENCRYPTED))) {
- if (!ECRYPTFS_CHECK_FLAG(crypt_stat->flags,
- ECRYPTFS_KEY_VALID)) {
- ecryptfs_printk(KERN_DEBUG, "Key is "
- "invalid; bailing out\n");
+ if (likely(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
+ if (!(crypt_stat->flags & ECRYPTFS_KEY_VALID)) {
+ printk(KERN_ERR "Key is invalid; bailing out\n");
rc = -EINVAL;
goto out;
}
} else {
+ printk(KERN_WARNING "%s: Encrypted flag not set\n",
+ __func__);
rc = -EINVAL;
- ecryptfs_printk(KERN_WARNING,
- "Called with crypt_stat->encrypted == 0\n");
goto out;
}
+ virt_len = crypt_stat->num_header_bytes_at_front;
+ order = get_order(virt_len);
/* Released in this function */
- page_virt = kmem_cache_alloc(ecryptfs_header_cache_0, SLAB_USER);
- if (!page_virt) {
- ecryptfs_printk(KERN_ERR, "Out of memory\n");
+ virt = (char *)ecryptfs_get_zeroed_pages(GFP_KERNEL, order);
+ if (!virt) {
+ printk(KERN_ERR "%s: Out of memory\n", __func__);
rc = -ENOMEM;
goto out;
}
- memset(page_virt, 0, PAGE_CACHE_SIZE);
- rc = ecryptfs_write_headers_virt(page_virt, crypt_stat,
+ rc = ecryptfs_write_headers_virt(virt, virt_len, &size, crypt_stat,
ecryptfs_dentry);
if (unlikely(rc)) {
- ecryptfs_printk(KERN_ERR, "Error whilst writing headers\n");
- memset(page_virt, 0, PAGE_CACHE_SIZE);
+ printk(KERN_ERR "%s: Error whilst writing headers; rc = [%d]\n",
+ __func__, rc);
+ goto out_free;
+ }
+ if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
+ rc = ecryptfs_write_metadata_to_xattr(ecryptfs_dentry, virt,
+ size);
+ else
+ rc = ecryptfs_write_metadata_to_contents(ecryptfs_dentry, virt,
+ virt_len);
+ if (rc) {
+ printk(KERN_ERR "%s: Error writing metadata out to lower file; "
+ "rc = [%d]\n", __func__, rc);
goto out_free;
}
- ecryptfs_printk(KERN_DEBUG,
- "Writing key packet set to underlying file\n");
- lower_file->f_pos = 0;
- oldfs = get_fs();
- set_fs(get_ds());
- ecryptfs_printk(KERN_DEBUG, "Calling lower_file->f_op->"
- "write() w/ header page; lower_file->f_pos = "
- "[0x%.16x]\n", lower_file->f_pos);
- lower_file->f_op->write(lower_file, (char __user *)page_virt,
- PAGE_CACHE_SIZE, &lower_file->f_pos);
- header_pages = ((crypt_stat->header_extent_size
- * crypt_stat->num_header_extents_at_front)
- / PAGE_CACHE_SIZE);
- memset(page_virt, 0, PAGE_CACHE_SIZE);
- current_header_page = 1;
- while (current_header_page < header_pages) {
- ecryptfs_printk(KERN_DEBUG, "Calling lower_file->f_op->"
- "write() w/ zero'd page; lower_file->f_pos = "
- "[0x%.16x]\n", lower_file->f_pos);
- lower_file->f_op->write(lower_file, (char __user *)page_virt,
- PAGE_CACHE_SIZE, &lower_file->f_pos);
- current_header_page++;
- }
- set_fs(oldfs);
- ecryptfs_printk(KERN_DEBUG,
- "Done writing key packet set to underlying file.\n");
out_free:
- kmem_cache_free(ecryptfs_header_cache_0, page_virt);
+ free_pages((unsigned long)virt, order);
out:
return rc;
}
+#define ECRYPTFS_DONT_VALIDATE_HEADER_SIZE 0
+#define ECRYPTFS_VALIDATE_HEADER_SIZE 1
static int parse_header_metadata(struct ecryptfs_crypt_stat *crypt_stat,
- char *virt, int *bytes_read)
+ char *virt, int *bytes_read,
+ int validate_header_size)
{
int rc = 0;
u32 header_extent_size;
u16 num_header_extents_at_front;
- memcpy(&header_extent_size, virt, 4);
- header_extent_size = be32_to_cpu(header_extent_size);
- virt += 4;
- memcpy(&num_header_extents_at_front, virt, 2);
- num_header_extents_at_front = be16_to_cpu(num_header_extents_at_front);
- crypt_stat->header_extent_size = (int)header_extent_size;
- crypt_stat->num_header_extents_at_front =
- (int)num_header_extents_at_front;
- (*bytes_read) = 6;
- if ((crypt_stat->header_extent_size
- * crypt_stat->num_header_extents_at_front)
- < ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE) {
+ header_extent_size = get_unaligned_be32(virt);
+ virt += sizeof(__be32);
+ num_header_extents_at_front = get_unaligned_be16(virt);
+ crypt_stat->num_header_bytes_at_front =
+ (((size_t)num_header_extents_at_front
+ * (size_t)header_extent_size));
+ (*bytes_read) = (sizeof(__be32) + sizeof(__be16));
+ if ((validate_header_size == ECRYPTFS_VALIDATE_HEADER_SIZE)
+ && (crypt_stat->num_header_bytes_at_front
+ < ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE)) {
rc = -EINVAL;
- ecryptfs_printk(KERN_WARNING, "Invalid header extent size: "
- "[%d]\n", crypt_stat->header_extent_size);
+ printk(KERN_WARNING "Invalid header size: [%zd]\n",
+ crypt_stat->num_header_bytes_at_front);
}
return rc;
}
/**
* set_default_header_data
+ * @crypt_stat: The cryptographic context
*
* For version 0 file format; this function is only for backwards
* compatibility for files created with the prior versions of
*/
static void set_default_header_data(struct ecryptfs_crypt_stat *crypt_stat)
{
- crypt_stat->header_extent_size = 4096;
- crypt_stat->num_header_extents_at_front = 1;
+ crypt_stat->num_header_bytes_at_front =
+ ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE;
}
/**
* ecryptfs_read_headers_virt
+ * @page_virt: The virtual address into which to read the headers
+ * @crypt_stat: The cryptographic context
+ * @ecryptfs_dentry: The eCryptfs dentry
+ * @validate_header_size: Whether to validate the header size while reading
*
* Read/parse the header data. The header format is detailed in the
* comment block for the ecryptfs_write_headers_virt() function.
*/
static int ecryptfs_read_headers_virt(char *page_virt,
struct ecryptfs_crypt_stat *crypt_stat,
- struct dentry *ecryptfs_dentry)
+ struct dentry *ecryptfs_dentry,
+ int validate_header_size)
{
int rc = 0;
int offset;
offset += bytes_read;
if (crypt_stat->file_version >= 1) {
rc = parse_header_metadata(crypt_stat, (page_virt + offset),
- &bytes_read);
+ &bytes_read, validate_header_size);
if (rc) {
ecryptfs_printk(KERN_WARNING, "Error reading header "
"metadata; rc = [%d]\n", rc);
}
/**
- * ecryptfs_read_headers
+ * ecryptfs_read_xattr_region
+ * @page_virt: The vitual address into which to read the xattr data
+ * @ecryptfs_inode: The eCryptfs inode
+ *
+ * Attempts to read the crypto metadata from the extended attribute
+ * region of the lower file.
+ *
+ * Returns zero on success; non-zero on error
+ */
+int ecryptfs_read_xattr_region(char *page_virt, struct inode *ecryptfs_inode)
+{
+ struct dentry *lower_dentry =
+ ecryptfs_inode_to_private(ecryptfs_inode)->lower_file->f_dentry;
+ ssize_t size;
+ int rc = 0;
+
+ size = ecryptfs_getxattr_lower(lower_dentry, ECRYPTFS_XATTR_NAME,
+ page_virt, ECRYPTFS_DEFAULT_EXTENT_SIZE);
+ if (size < 0) {
+ if (unlikely(ecryptfs_verbosity > 0))
+ printk(KERN_INFO "Error attempting to read the [%s] "
+ "xattr from the lower file; return value = "
+ "[%zd]\n", ECRYPTFS_XATTR_NAME, size);
+ rc = -EINVAL;
+ goto out;
+ }
+out:
+ return rc;
+}
+
+int ecryptfs_read_and_validate_xattr_region(char *page_virt,
+ struct dentry *ecryptfs_dentry)
+{
+ int rc;
+
+ rc = ecryptfs_read_xattr_region(page_virt, ecryptfs_dentry->d_inode);
+ if (rc)
+ goto out;
+ if (!contains_ecryptfs_marker(page_virt + ECRYPTFS_FILE_SIZE_BYTES)) {
+ printk(KERN_WARNING "Valid data found in [%s] xattr, but "
+ "the marker is invalid\n", ECRYPTFS_XATTR_NAME);
+ rc = -EINVAL;
+ }
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_read_metadata
+ *
+ * Common entry point for reading file metadata. From here, we could
+ * retrieve the header information from the header region of the file,
+ * the xattr region of the file, or some other repostory that is
+ * stored separately from the file itself. The current implementation
+ * supports retrieving the metadata information from the file contents
+ * and from the xattr region.
*
* Returns zero if valid headers found and parsed; non-zero otherwise
*/
-int ecryptfs_read_headers(struct dentry *ecryptfs_dentry,
- struct file *lower_file)
+int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry)
{
int rc = 0;
char *page_virt = NULL;
- mm_segment_t oldfs;
- ssize_t bytes_read;
+ struct inode *ecryptfs_inode = ecryptfs_dentry->d_inode;
struct ecryptfs_crypt_stat *crypt_stat =
- &ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat;
+ &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat;
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
+ &ecryptfs_superblock_to_private(
+ ecryptfs_dentry->d_sb)->mount_crypt_stat;
+ ecryptfs_copy_mount_wide_flags_to_inode_flags(crypt_stat,
+ mount_crypt_stat);
/* Read the first page from the underlying file */
- page_virt = kmem_cache_alloc(ecryptfs_header_cache_1, SLAB_USER);
+ page_virt = kmem_cache_alloc(ecryptfs_header_cache_1, GFP_USER);
if (!page_virt) {
rc = -ENOMEM;
- ecryptfs_printk(KERN_ERR, "Unable to allocate page_virt\n");
+ printk(KERN_ERR "%s: Unable to allocate page_virt\n",
+ __func__);
goto out;
}
- lower_file->f_pos = 0;
- oldfs = get_fs();
- set_fs(get_ds());
- bytes_read = lower_file->f_op->read(lower_file,
- (char __user *)page_virt,
- ECRYPTFS_DEFAULT_EXTENT_SIZE,
- &lower_file->f_pos);
- set_fs(oldfs);
- if (bytes_read != ECRYPTFS_DEFAULT_EXTENT_SIZE) {
- rc = -EINVAL;
- goto out;
- }
- rc = ecryptfs_read_headers_virt(page_virt, crypt_stat,
- ecryptfs_dentry);
+ rc = ecryptfs_read_lower(page_virt, 0, crypt_stat->extent_size,
+ ecryptfs_inode);
+ if (rc >= 0)
+ rc = ecryptfs_read_headers_virt(page_virt, crypt_stat,
+ ecryptfs_dentry,
+ ECRYPTFS_VALIDATE_HEADER_SIZE);
if (rc) {
- ecryptfs_printk(KERN_DEBUG, "Valid eCryptfs headers not "
- "found\n");
- rc = -EINVAL;
+ rc = ecryptfs_read_xattr_region(page_virt, ecryptfs_inode);
+ if (rc) {
+ printk(KERN_DEBUG "Valid eCryptfs headers not found in "
+ "file header region or xattr region\n");
+ rc = -EINVAL;
+ goto out;
+ }
+ rc = ecryptfs_read_headers_virt(page_virt, crypt_stat,
+ ecryptfs_dentry,
+ ECRYPTFS_DONT_VALIDATE_HEADER_SIZE);
+ if (rc) {
+ printk(KERN_DEBUG "Valid eCryptfs headers not found in "
+ "file xattr region either\n");
+ rc = -EINVAL;
+ }
+ if (crypt_stat->mount_crypt_stat->flags
+ & ECRYPTFS_XATTR_METADATA_ENABLED) {
+ crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
+ } else {
+ printk(KERN_WARNING "Attempt to access file with "
+ "crypto metadata only in the extended attribute "
+ "region, but eCryptfs was mounted without "
+ "xattr support enabled. eCryptfs will not treat "
+ "this like an encrypted file.\n");
+ rc = -EINVAL;
+ }
}
out:
if (page_virt) {
}
/**
- * ecryptfs_encode_filename - converts a plaintext file name to cipher text
- * @crypt_stat: The crypt_stat struct associated with the file anem to encode
- * @name: The plaintext name
- * @length: The length of the plaintext
- * @encoded_name: The encypted name
+ * ecryptfs_encrypt_filename - encrypt filename
*
- * Encrypts and encodes a filename into something that constitutes a
- * valid filename for a filesystem, with printable characters.
+ * CBC-encrypts the filename. We do not want to encrypt the same
+ * filename with the same key and IV, which may happen with hard
+ * links, so we prepend random bits to each filename.
*
- * We assume that we have a properly initialized crypto context,
- * pointed to by crypt_stat->tfm.
- *
- * TODO: Implement filename decoding and decryption here, in place of
- * memcpy. We are keeping the framework around for now to (1)
- * facilitate testing of the components needed to implement filename
- * encryption and (2) to provide a code base from which other
- * developers in the community can easily implement this feature.
- *
- * Returns the length of encoded filename; negative if error
+ * Returns zero on success; non-zero otherwise
*/
-int
-ecryptfs_encode_filename(struct ecryptfs_crypt_stat *crypt_stat,
- const char *name, int length, char **encoded_name)
+static int
+ecryptfs_encrypt_filename(struct ecryptfs_filename *filename,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat)
{
- int error = 0;
+ int rc = 0;
- (*encoded_name) = kmalloc(length + 2, GFP_KERNEL);
- if (!(*encoded_name)) {
- error = -ENOMEM;
+ filename->encrypted_filename = NULL;
+ filename->encrypted_filename_size = 0;
+ if ((crypt_stat && (crypt_stat->flags & ECRYPTFS_ENCFN_USE_MOUNT_FNEK))
+ || (mount_crypt_stat && (mount_crypt_stat->flags
+ & ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK))) {
+ size_t packet_size;
+ size_t remaining_bytes;
+
+ rc = ecryptfs_write_tag_70_packet(
+ NULL, NULL,
+ &filename->encrypted_filename_size,
+ mount_crypt_stat, NULL,
+ filename->filename_size);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to get packet "
+ "size for tag 72; rc = [%d]\n", __func__,
+ rc);
+ filename->encrypted_filename_size = 0;
+ goto out;
+ }
+ filename->encrypted_filename =
+ kmalloc(filename->encrypted_filename_size, GFP_KERNEL);
+ if (!filename->encrypted_filename) {
+ printk(KERN_ERR "%s: Out of memory whilst attempting "
+ "to kmalloc [%zd] bytes\n", __func__,
+ filename->encrypted_filename_size);
+ rc = -ENOMEM;
+ goto out;
+ }
+ remaining_bytes = filename->encrypted_filename_size;
+ rc = ecryptfs_write_tag_70_packet(filename->encrypted_filename,
+ &remaining_bytes,
+ &packet_size,
+ mount_crypt_stat,
+ filename->filename,
+ filename->filename_size);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to generate "
+ "tag 70 packet; rc = [%d]\n", __func__,
+ rc);
+ kfree(filename->encrypted_filename);
+ filename->encrypted_filename = NULL;
+ filename->encrypted_filename_size = 0;
+ goto out;
+ }
+ filename->encrypted_filename_size = packet_size;
+ } else {
+ printk(KERN_ERR "%s: No support for requested filename "
+ "encryption method in this release\n", __func__);
+ rc = -EOPNOTSUPP;
goto out;
}
- /* TODO: Filename encryption is a scheduled feature for a
- * future version of eCryptfs. This function is here only for
- * the purpose of providing a framework for other developers
- * to easily implement filename encryption. Hint: Replace this
- * memcpy() with a call to encrypt and encode the
- * filename, the set the length accordingly. */
- memcpy((void *)(*encoded_name), (void *)name, length);
- (*encoded_name)[length] = '\0';
- error = length + 1;
out:
- return error;
+ return rc;
}
-/**
- * ecryptfs_decode_filename - converts the cipher text name to plaintext
- * @crypt_stat: The crypt_stat struct associated with the file
- * @name: The filename in cipher text
- * @length: The length of the cipher text name
- * @decrypted_name: The plaintext name
- *
- * Decodes and decrypts the filename.
- *
- * We assume that we have a properly initialized crypto context,
- * pointed to by crypt_stat->tfm.
- *
- * TODO: Implement filename decoding and decryption here, in place of
- * memcpy. We are keeping the framework around for now to (1)
- * facilitate testing of the components needed to implement filename
- * encryption and (2) to provide a code base from which other
- * developers in the community can easily implement this feature.
- *
- * Returns the length of decoded filename; negative if error
- */
-int
-ecryptfs_decode_filename(struct ecryptfs_crypt_stat *crypt_stat,
- const char *name, int length, char **decrypted_name)
+static int ecryptfs_copy_filename(char **copied_name, size_t *copied_name_size,
+ const char *name, size_t name_size)
{
- int error = 0;
+ int rc = 0;
- (*decrypted_name) = kmalloc(length + 2, GFP_KERNEL);
- if (!(*decrypted_name)) {
- error = -ENOMEM;
+ (*copied_name) = kmalloc((name_size + 1), GFP_KERNEL);
+ if (!(*copied_name)) {
+ rc = -ENOMEM;
goto out;
}
- /* TODO: Filename encryption is a scheduled feature for a
- * future version of eCryptfs. This function is here only for
- * the purpose of providing a framework for other developers
- * to easily implement filename encryption. Hint: Replace this
- * memcpy() with a call to decode and decrypt the
- * filename, the set the length accordingly. */
- memcpy((void *)(*decrypted_name), (void *)name, length);
- (*decrypted_name)[length + 1] = '\0'; /* Only for convenience
+ memcpy((void *)(*copied_name), (void *)name, name_size);
+ (*copied_name)[(name_size)] = '\0'; /* Only for convenience
* in printing out the
* string in debug
* messages */
- error = length;
+ (*copied_name_size) = name_size;
out:
- return error;
+ return rc;
}
/**
- * ecryptfs_process_cipher - Perform cipher initialization.
+ * ecryptfs_process_key_cipher - Perform key cipher initialization.
* @key_tfm: Crypto context for key material, set by this function
* @cipher_name: Name of the cipher
* @key_size: Size of the key in bytes
* should be released by other functions, such as on a superblock put
* event, regardless of whether this function succeeds for fails.
*/
-int
-ecryptfs_process_cipher(struct crypto_tfm **key_tfm, char *cipher_name,
- size_t *key_size)
+static int
+ecryptfs_process_key_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;
if (*key_size > ECRYPTFS_MAX_KEY_BYTES) {
rc = -EINVAL;
- printk(KERN_ERR "Requested key size is [%Zd] bytes; maximum "
+ printk(KERN_ERR "Requested key size is [%zd] bytes; maximum "
"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", full_alg_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);
+ printk(KERN_ERR "Error attempting to set key of size [%zd] for "
+ "cipher [%s]; rc = [%d]\n", *key_size, full_alg_name,
+ rc);
rc = -EINVAL;
goto out;
}
out:
return rc;
}
+
+struct kmem_cache *ecryptfs_key_tfm_cache;
+static struct list_head key_tfm_list;
+struct mutex key_tfm_list_mutex;
+
+int ecryptfs_init_crypto(void)
+{
+ mutex_init(&key_tfm_list_mutex);
+ INIT_LIST_HEAD(&key_tfm_list);
+ return 0;
+}
+
+/**
+ * ecryptfs_destroy_crypto - free all cached key_tfms on key_tfm_list
+ *
+ * Called only at module unload time
+ */
+int ecryptfs_destroy_crypto(void)
+{
+ struct ecryptfs_key_tfm *key_tfm, *key_tfm_tmp;
+
+ mutex_lock(&key_tfm_list_mutex);
+ list_for_each_entry_safe(key_tfm, key_tfm_tmp, &key_tfm_list,
+ key_tfm_list) {
+ list_del(&key_tfm->key_tfm_list);
+ if (key_tfm->key_tfm)
+ crypto_free_blkcipher(key_tfm->key_tfm);
+ kmem_cache_free(ecryptfs_key_tfm_cache, key_tfm);
+ }
+ mutex_unlock(&key_tfm_list_mutex);
+ return 0;
+}
+
+int
+ecryptfs_add_new_key_tfm(struct ecryptfs_key_tfm **key_tfm, char *cipher_name,
+ size_t key_size)
+{
+ struct ecryptfs_key_tfm *tmp_tfm;
+ int rc = 0;
+
+ BUG_ON(!mutex_is_locked(&key_tfm_list_mutex));
+
+ tmp_tfm = kmem_cache_alloc(ecryptfs_key_tfm_cache, GFP_KERNEL);
+ if (key_tfm != NULL)
+ (*key_tfm) = tmp_tfm;
+ if (!tmp_tfm) {
+ rc = -ENOMEM;
+ printk(KERN_ERR "Error attempting to allocate from "
+ "ecryptfs_key_tfm_cache\n");
+ goto out;
+ }
+ mutex_init(&tmp_tfm->key_tfm_mutex);
+ strncpy(tmp_tfm->cipher_name, cipher_name,
+ ECRYPTFS_MAX_CIPHER_NAME_SIZE);
+ tmp_tfm->cipher_name[ECRYPTFS_MAX_CIPHER_NAME_SIZE] = '\0';
+ tmp_tfm->key_size = key_size;
+ rc = ecryptfs_process_key_cipher(&tmp_tfm->key_tfm,
+ tmp_tfm->cipher_name,
+ &tmp_tfm->key_size);
+ if (rc) {
+ printk(KERN_ERR "Error attempting to initialize key TFM "
+ "cipher with name = [%s]; rc = [%d]\n",
+ tmp_tfm->cipher_name, rc);
+ kmem_cache_free(ecryptfs_key_tfm_cache, tmp_tfm);
+ if (key_tfm != NULL)
+ (*key_tfm) = NULL;
+ goto out;
+ }
+ list_add(&tmp_tfm->key_tfm_list, &key_tfm_list);
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_tfm_exists - Search for existing tfm for cipher_name.
+ * @cipher_name: the name of the cipher to search for
+ * @key_tfm: set to corresponding tfm if found
+ *
+ * Searches for cached key_tfm matching @cipher_name
+ * Must be called with &key_tfm_list_mutex held
+ * Returns 1 if found, with @key_tfm set
+ * Returns 0 if not found, with @key_tfm set to NULL
+ */
+int ecryptfs_tfm_exists(char *cipher_name, struct ecryptfs_key_tfm **key_tfm)
+{
+ struct ecryptfs_key_tfm *tmp_key_tfm;
+
+ BUG_ON(!mutex_is_locked(&key_tfm_list_mutex));
+
+ list_for_each_entry(tmp_key_tfm, &key_tfm_list, key_tfm_list) {
+ if (strcmp(tmp_key_tfm->cipher_name, cipher_name) == 0) {
+ if (key_tfm)
+ (*key_tfm) = tmp_key_tfm;
+ return 1;
+ }
+ }
+ if (key_tfm)
+ (*key_tfm) = NULL;
+ return 0;
+}
+
+/**
+ * ecryptfs_get_tfm_and_mutex_for_cipher_name
+ *
+ * @tfm: set to cached tfm found, or new tfm created
+ * @tfm_mutex: set to mutex for cached tfm found, or new tfm created
+ * @cipher_name: the name of the cipher to search for and/or add
+ *
+ * Sets pointers to @tfm & @tfm_mutex matching @cipher_name.
+ * Searches for cached item first, and creates new if not found.
+ * Returns 0 on success, non-zero if adding new cipher failed
+ */
+int ecryptfs_get_tfm_and_mutex_for_cipher_name(struct crypto_blkcipher **tfm,
+ struct mutex **tfm_mutex,
+ char *cipher_name)
+{
+ struct ecryptfs_key_tfm *key_tfm;
+ int rc = 0;
+
+ (*tfm) = NULL;
+ (*tfm_mutex) = NULL;
+
+ mutex_lock(&key_tfm_list_mutex);
+ if (!ecryptfs_tfm_exists(cipher_name, &key_tfm)) {
+ rc = ecryptfs_add_new_key_tfm(&key_tfm, cipher_name, 0);
+ if (rc) {
+ printk(KERN_ERR "Error adding new key_tfm to list; "
+ "rc = [%d]\n", rc);
+ goto out;
+ }
+ }
+ (*tfm) = key_tfm->key_tfm;
+ (*tfm_mutex) = &key_tfm->key_tfm_mutex;
+out:
+ mutex_unlock(&key_tfm_list_mutex);
+ return rc;
+}
+
+/* 64 characters forming a 6-bit target field */
+static unsigned char *portable_filename_chars = ("-.0123456789ABCD"
+ "EFGHIJKLMNOPQRST"
+ "UVWXYZabcdefghij"
+ "klmnopqrstuvwxyz");
+
+/* We could either offset on every reverse map or just pad some 0x00's
+ * at the front here */
+static const unsigned char filename_rev_map[] = {
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 7 */
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 15 */
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 23 */
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 31 */
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 39 */
+ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, /* 47 */
+ 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, /* 55 */
+ 0x0A, 0x0B, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* 63 */
+ 0x00, 0x0C, 0x0D, 0x0E, 0x0F, 0x10, 0x11, 0x12, /* 71 */
+ 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1A, /* 79 */
+ 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20, 0x21, 0x22, /* 87 */
+ 0x23, 0x24, 0x25, 0x00, 0x00, 0x00, 0x00, 0x00, /* 95 */
+ 0x00, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, 0x2C, /* 103 */
+ 0x2D, 0x2E, 0x2F, 0x30, 0x31, 0x32, 0x33, 0x34, /* 111 */
+ 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, 0x3C, /* 119 */
+ 0x3D, 0x3E, 0x3F
+};
+
+/**
+ * ecryptfs_encode_for_filename
+ * @dst: Destination location for encoded filename
+ * @dst_size: Size of the encoded filename in bytes
+ * @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,
+ unsigned char *src, size_t src_size)
+{
+ size_t num_blocks;
+ size_t block_num = 0;
+ size_t dst_offset = 0;
+ unsigned char last_block[3];
+
+ if (src_size == 0) {
+ (*dst_size) = 0;
+ goto out;
+ }
+ num_blocks = (src_size / 3);
+ if ((src_size % 3) == 0) {
+ memcpy(last_block, (&src[src_size - 3]), 3);
+ } else {
+ num_blocks++;
+ last_block[2] = 0x00;
+ switch (src_size % 3) {
+ case 1:
+ last_block[0] = src[src_size - 1];
+ last_block[1] = 0x00;
+ break;
+ case 2:
+ last_block[0] = src[src_size - 2];
+ last_block[1] = src[src_size - 1];
+ }
+ }
+ (*dst_size) = (num_blocks * 4);
+ if (!dst)
+ goto out;
+ while (block_num < num_blocks) {
+ unsigned char *src_block;
+ unsigned char dst_block[4];
+
+ if (block_num == (num_blocks - 1))
+ src_block = last_block;
+ else
+ src_block = &src[block_num * 3];
+ dst_block[0] = ((src_block[0] >> 2) & 0x3F);
+ dst_block[1] = (((src_block[0] << 4) & 0x30)
+ | ((src_block[1] >> 4) & 0x0F));
+ dst_block[2] = (((src_block[1] << 2) & 0x3C)
+ | ((src_block[2] >> 6) & 0x03));
+ dst_block[3] = (src_block[2] & 0x3F);
+ dst[dst_offset++] = portable_filename_chars[dst_block[0]];
+ dst[dst_offset++] = portable_filename_chars[dst_block[1]];
+ dst[dst_offset++] = portable_filename_chars[dst_block[2]];
+ dst[dst_offset++] = portable_filename_chars[dst_block[3]];
+ block_num++;
+ }
+out:
+ return;
+}
+
+/**
+ * ecryptfs_decode_from_filename
+ * @dst: If NULL, this function only sets @dst_size and returns. If
+ * non-NULL, this function decodes the encoded octets in @src
+ * into the memory that @dst points to.
+ * @dst_size: Set to the size of the decoded string.
+ * @src: The encoded set of octets to decode.
+ * @src_size: The size of the encoded set of octets to decode.
+ */
+static void
+ecryptfs_decode_from_filename(unsigned char *dst, size_t *dst_size,
+ const unsigned char *src, size_t src_size)
+{
+ u8 current_bit_offset = 0;
+ size_t src_byte_offset = 0;
+ size_t dst_byte_offset = 0;
+
+ if (dst == NULL) {
+ /* Not exact; conservatively long. Every block of 4
+ * encoded characters decodes into a block of 3
+ * decoded characters. This segment of code provides
+ * the caller with the maximum amount of allocated
+ * space that @dst will need to point to in a
+ * subsequent call. */
+ (*dst_size) = (((src_size + 1) * 3) / 4);
+ goto out;
+ }
+ while (src_byte_offset < src_size) {
+ unsigned char src_byte =
+ filename_rev_map[(int)src[src_byte_offset]];
+
+ switch (current_bit_offset) {
+ case 0:
+ dst[dst_byte_offset] = (src_byte << 2);
+ current_bit_offset = 6;
+ break;
+ case 6:
+ dst[dst_byte_offset++] |= (src_byte >> 4);
+ dst[dst_byte_offset] = ((src_byte & 0xF)
+ << 4);
+ current_bit_offset = 4;
+ break;
+ case 4:
+ dst[dst_byte_offset++] |= (src_byte >> 2);
+ dst[dst_byte_offset] = (src_byte << 6);
+ current_bit_offset = 2;
+ break;
+ case 2:
+ dst[dst_byte_offset++] |= (src_byte);
+ dst[dst_byte_offset] = 0;
+ current_bit_offset = 0;
+ break;
+ }
+ src_byte_offset++;
+ }
+ (*dst_size) = dst_byte_offset;
+out:
+ return;
+}
+
+/**
+ * ecryptfs_encrypt_and_encode_filename - converts a plaintext file name to cipher text
+ * @crypt_stat: The crypt_stat struct associated with the file anem to encode
+ * @name: The plaintext name
+ * @length: The length of the plaintext
+ * @encoded_name: The encypted name
+ *
+ * Encrypts and encodes a filename into something that constitutes a
+ * valid filename for a filesystem, with printable characters.
+ *
+ * We assume that we have a properly initialized crypto context,
+ * pointed to by crypt_stat->tfm.
+ *
+ * Returns zero on success; non-zero on otherwise
+ */
+int ecryptfs_encrypt_and_encode_filename(
+ char **encoded_name,
+ size_t *encoded_name_size,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ struct ecryptfs_mount_crypt_stat *mount_crypt_stat,
+ const char *name, size_t name_size)
+{
+ size_t encoded_name_no_prefix_size;
+ int rc = 0;
+
+ (*encoded_name) = NULL;
+ (*encoded_name_size) = 0;
+ if ((crypt_stat && (crypt_stat->flags & ECRYPTFS_ENCRYPT_FILENAMES))
+ || (mount_crypt_stat && (mount_crypt_stat->flags
+ & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES))) {
+ struct ecryptfs_filename *filename;
+
+ filename = kzalloc(sizeof(*filename), GFP_KERNEL);
+ if (!filename) {
+ printk(KERN_ERR "%s: Out of memory whilst attempting "
+ "to kzalloc [%zd] bytes\n", __func__,
+ sizeof(*filename));
+ rc = -ENOMEM;
+ goto out;
+ }
+ filename->filename = (char *)name;
+ filename->filename_size = name_size;
+ rc = ecryptfs_encrypt_filename(filename, crypt_stat,
+ mount_crypt_stat);
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to encrypt "
+ "filename; rc = [%d]\n", __func__, rc);
+ kfree(filename);
+ goto out;
+ }
+ ecryptfs_encode_for_filename(
+ NULL, &encoded_name_no_prefix_size,
+ filename->encrypted_filename,
+ filename->encrypted_filename_size);
+ if ((crypt_stat && (crypt_stat->flags
+ & ECRYPTFS_ENCFN_USE_MOUNT_FNEK))
+ || (mount_crypt_stat
+ && (mount_crypt_stat->flags
+ & ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK)))
+ (*encoded_name_size) =
+ (ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE
+ + encoded_name_no_prefix_size);
+ else
+ (*encoded_name_size) =
+ (ECRYPTFS_FEK_ENCRYPTED_FILENAME_PREFIX_SIZE
+ + encoded_name_no_prefix_size);
+ (*encoded_name) = kmalloc((*encoded_name_size) + 1, GFP_KERNEL);
+ if (!(*encoded_name)) {
+ printk(KERN_ERR "%s: Out of memory whilst attempting "
+ "to kzalloc [%zd] bytes\n", __func__,
+ (*encoded_name_size));
+ rc = -ENOMEM;
+ kfree(filename->encrypted_filename);
+ kfree(filename);
+ goto out;
+ }
+ if ((crypt_stat && (crypt_stat->flags
+ & ECRYPTFS_ENCFN_USE_MOUNT_FNEK))
+ || (mount_crypt_stat
+ && (mount_crypt_stat->flags
+ & ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK))) {
+ memcpy((*encoded_name),
+ ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX,
+ ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE);
+ ecryptfs_encode_for_filename(
+ ((*encoded_name)
+ + ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE),
+ &encoded_name_no_prefix_size,
+ filename->encrypted_filename,
+ filename->encrypted_filename_size);
+ (*encoded_name_size) =
+ (ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE
+ + encoded_name_no_prefix_size);
+ (*encoded_name)[(*encoded_name_size)] = '\0';
+ (*encoded_name_size)++;
+ } else {
+ rc = -EOPNOTSUPP;
+ }
+ if (rc) {
+ printk(KERN_ERR "%s: Error attempting to encode "
+ "encrypted filename; rc = [%d]\n", __func__,
+ rc);
+ kfree((*encoded_name));
+ (*encoded_name) = NULL;
+ (*encoded_name_size) = 0;
+ }
+ kfree(filename->encrypted_filename);
+ kfree(filename);
+ } else {
+ rc = ecryptfs_copy_filename(encoded_name,
+ encoded_name_size,
+ name, name_size);
+ }
+out:
+ return rc;
+}
+
+/**
+ * ecryptfs_decode_and_decrypt_filename - converts the encoded cipher text name to decoded plaintext
+ * @plaintext_name: The plaintext name
+ * @plaintext_name_size: The plaintext name size
+ * @ecryptfs_dir_dentry: eCryptfs directory dentry
+ * @name: The filename in cipher text
+ * @name_size: The cipher text name size
+ *
+ * Decrypts and decodes the filename.
+ *
+ * Returns zero on error; non-zero otherwise
+ */
+int ecryptfs_decode_and_decrypt_filename(char **plaintext_name,
+ size_t *plaintext_name_size,
+ struct dentry *ecryptfs_dir_dentry,
+ 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;
+ char *decoded_name;
+ size_t decoded_name_size;
+ size_t packet_size;
+ int rc = 0;
+
+ if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES)
+ && !(mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED)
+ && (name_size > ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE)
+ && (strncmp(name, ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX,
+ ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE) == 0)) {
+ const char *orig_name = name;
+ size_t orig_name_size = name_size;
+
+ name += ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE;
+ name_size -= ECRYPTFS_FNEK_ENCRYPTED_FILENAME_PREFIX_SIZE;
+ ecryptfs_decode_from_filename(NULL, &decoded_name_size,
+ name, name_size);
+ decoded_name = kmalloc(decoded_name_size, GFP_KERNEL);
+ if (!decoded_name) {
+ printk(KERN_ERR "%s: Out of memory whilst attempting "
+ "to kmalloc [%zd] bytes\n", __func__,
+ decoded_name_size);
+ rc = -ENOMEM;
+ goto out;
+ }
+ ecryptfs_decode_from_filename(decoded_name, &decoded_name_size,
+ name, name_size);
+ rc = ecryptfs_parse_tag_70_packet(plaintext_name,
+ plaintext_name_size,
+ &packet_size,
+ mount_crypt_stat,
+ decoded_name,
+ decoded_name_size);
+ if (rc) {
+ printk(KERN_INFO "%s: Could not parse tag 70 packet "
+ "from filename; copying through filename "
+ "as-is\n", __func__);
+ rc = ecryptfs_copy_filename(plaintext_name,
+ plaintext_name_size,
+ orig_name, orig_name_size);
+ goto out_free;
+ }
+ } else {
+ rc = ecryptfs_copy_filename(plaintext_name,
+ plaintext_name_size,
+ name, name_size);
+ goto out;
+ }
+out_free:
+ kfree(decoded_name);
+out:
+ return rc;
+}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff