#include <linux/crypto.h>
#include <linux/file.h>
#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include <asm/unaligned.h>
#include "ecryptfs_kernel.h"
static int
if (rc) {
printk(KERN_ERR
"%s: Error initializing crypto hash; rc = [%d]\n",
- __FUNCTION__, rc);
+ __func__, rc);
goto out;
}
rc = crypto_hash_update(&desc, &sg, len);
if (rc) {
printk(KERN_ERR
"%s: Error updating crypto hash; rc = [%d]\n",
- __FUNCTION__, rc);
+ __func__, rc);
goto out;
}
rc = crypto_hash_final(&desc, dst);
if (rc) {
printk(KERN_ERR
"%s: Error finalizing crypto hash; rc = [%d]\n",
- __FUNCTION__, rc);
+ __func__, rc);
goto out;
}
out:
*
* Returns zero on success; non-zero on error.
*/
-static int ecryptfs_derive_iv(char *iv, struct ecryptfs_crypt_stat *crypt_stat,
- loff_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];
crypto_free_blkcipher(crypt_stat->tfm);
if (crypt_stat->hash_tfm)
crypto_free_hash(crypt_stat->hash_tfm);
- mutex_lock(&crypt_stat->keysig_list_mutex);
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);
}
- mutex_unlock(&crypt_stat->keysig_list_mutex);
memset(crypt_stat, 0, sizeof(struct ecryptfs_crypt_stat));
}
}
/* 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 (!(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);
*
* Convert an eCryptfs page index into a lower byte offset
*/
-void ecryptfs_lower_offset_for_extent(loff_t *offset, loff_t extent_num,
- struct ecryptfs_crypt_stat *crypt_stat)
+static void ecryptfs_lower_offset_for_extent(loff_t *offset, loff_t extent_num,
+ struct ecryptfs_crypt_stat *crypt_stat)
{
- (*offset) = ((crypt_stat->extent_size
- * crypt_stat->num_header_extents_at_front)
- + (crypt_stat->extent_size * extent_num));
+ (*offset) = ecryptfs_lower_header_size(crypt_stat)
+ + (crypt_stat->extent_size * extent_num);
}
/**
if (rc < 0) {
printk(KERN_ERR "%s: Error attempting to encrypt page with "
"page->index = [%ld], extent_offset = [%ld]; "
- "rc = [%d]\n", __FUNCTION__, page->index, extent_offset,
+ "rc = [%d]\n", __func__, page->index, extent_offset,
rc);
goto out;
}
{
struct inode *ecryptfs_inode;
struct ecryptfs_crypt_stat *crypt_stat;
- char *enc_extent_virt = NULL;
- struct page *enc_extent_page;
+ char *enc_extent_virt;
+ struct page *enc_extent_page = NULL;
loff_t extent_offset;
int rc = 0;
ecryptfs_inode = page->mapping->host;
crypt_stat =
&(ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat);
- if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
- rc = ecryptfs_write_lower_page_segment(ecryptfs_inode, page,
- 0, PAGE_CACHE_SIZE);
- if (rc)
- printk(KERN_ERR "%s: Error attempting to copy "
- "page at index [%ld]\n", __FUNCTION__,
- page->index);
- goto out;
- }
- enc_extent_virt = kmalloc(PAGE_CACHE_SIZE, GFP_USER);
- if (!enc_extent_virt) {
+ 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;
}
- enc_extent_page = virt_to_page(enc_extent_virt);
+ enc_extent_virt = kmap(enc_extent_page);
for (extent_offset = 0;
extent_offset < (PAGE_CACHE_SIZE / crypt_stat->extent_size);
extent_offset++) {
extent_offset);
if (rc) {
printk(KERN_ERR "%s: Error encrypting extent; "
- "rc = [%d]\n", __FUNCTION__, rc);
+ "rc = [%d]\n", __func__, rc);
goto out;
}
ecryptfs_lower_offset_for_extent(
+ extent_offset), crypt_stat);
rc = ecryptfs_write_lower(ecryptfs_inode, enc_extent_virt,
offset, crypt_stat->extent_size);
- if (rc) {
+ if (rc < 0) {
ecryptfs_printk(KERN_ERR, "Error attempting "
"to write lower page; rc = [%d]"
"\n", rc);
goto out;
}
}
+ rc = 0;
out:
- kfree(enc_extent_virt);
+ if (enc_extent_page) {
+ kunmap(enc_extent_page);
+ __free_page(enc_extent_page);
+ }
return rc;
}
if (rc < 0) {
printk(KERN_ERR "%s: Error attempting to decrypt to page with "
"page->index = [%ld], extent_offset = [%ld]; "
- "rc = [%d]\n", __FUNCTION__, page->index, extent_offset,
+ "rc = [%d]\n", __func__, page->index, extent_offset,
rc);
goto out;
}
{
struct inode *ecryptfs_inode;
struct ecryptfs_crypt_stat *crypt_stat;
- char *enc_extent_virt = NULL;
- struct page *enc_extent_page;
+ char *enc_extent_virt;
+ struct page *enc_extent_page = NULL;
unsigned long extent_offset;
int rc = 0;
ecryptfs_inode = page->mapping->host;
crypt_stat =
&(ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat);
- if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
- rc = ecryptfs_read_lower_page_segment(page, page->index, 0,
- PAGE_CACHE_SIZE,
- ecryptfs_inode);
- if (rc)
- printk(KERN_ERR "%s: Error attempting to copy "
- "page at index [%ld]\n", __FUNCTION__,
- page->index);
- goto out;
- }
- enc_extent_virt = kmalloc(PAGE_CACHE_SIZE, GFP_USER);
- if (!enc_extent_virt) {
+ 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;
}
- enc_extent_page = virt_to_page(enc_extent_virt);
+ enc_extent_virt = kmap(enc_extent_page);
for (extent_offset = 0;
extent_offset < (PAGE_CACHE_SIZE / crypt_stat->extent_size);
extent_offset++) {
rc = ecryptfs_read_lower(enc_extent_virt, offset,
crypt_stat->extent_size,
ecryptfs_inode);
- if (rc) {
+ if (rc < 0) {
ecryptfs_printk(KERN_ERR, "Error attempting "
"to read lower page; rc = [%d]"
"\n", rc);
extent_offset);
if (rc) {
printk(KERN_ERR "%s: Error encrypting extent; "
- "rc = [%d]\n", __FUNCTION__, rc);
+ "rc = [%d]\n", __func__, rc);
goto out;
}
}
out:
- kfree(enc_extent_virt);
+ if (enc_extent_page) {
+ kunmap(enc_extent_page);
+ __free_page(enc_extent_page);
+ }
return rc;
}
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);
set_extent_mask_and_shift(crypt_stat);
crypt_stat->iv_bytes = ECRYPTFS_DEFAULT_IV_BYTES;
if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR)
- crypt_stat->num_header_extents_at_front = 0;
+ crypt_stat->metadata_size = ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE;
else {
if (PAGE_CACHE_SIZE <= ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE)
- crypt_stat->num_header_extents_at_front =
- (ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE
- / crypt_stat->extent_size);
+ crypt_stat->metadata_size =
+ ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE;
else
- crypt_stat->num_header_extents_at_front =
- (PAGE_CACHE_SIZE / crypt_stat->extent_size);
+ crypt_stat->metadata_size = PAGE_CACHE_SIZE;
}
}
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_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);
- mutex_unlock(
- &mount_crypt_stat->global_auth_tok_list_mutex);
goto out;
}
}
- mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex);
+
out:
+ mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex);
+ mutex_unlock(&crypt_stat->keysig_list_mutex);
return rc;
}
{
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]; "
static struct ecryptfs_flag_map_elem ecryptfs_flag_map[] = {
{0x00000001, ECRYPTFS_ENABLE_HMAC},
{0x00000002, ECRYPTFS_ENCRYPTED},
- {0x00000004, ECRYPTFS_METADATA_IN_XATTR}
+ {0x00000004, ECRYPTFS_METADATA_IN_XATTR},
+ {0x00000008, ECRYPTFS_ENCRYPT_FILENAMES}
};
/**
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) {
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;
}
-static void
-write_ecryptfs_flags(char *page_virt, struct ecryptfs_crypt_stat *crypt_stat,
- size_t *written)
+void ecryptfs_write_crypt_stat_flags(char *page_virt,
+ struct ecryptfs_crypt_stat *crypt_stat,
+ size_t *written)
{
u32 flags = 0;
int i;
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
- * @crypt_stat: The cryptographic context
+ * @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;
&(ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat);
int rc;
+ 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) {
+ if (rc < 0) {
printk(KERN_ERR "%s: Error reading header region; rc = [%d]\n",
- __FUNCTION__, rc);
+ __func__, rc);
goto out;
}
if (!contains_ecryptfs_marker(data + ECRYPTFS_FILE_SIZE_BYTES)) {
rc = -EINVAL;
- ecryptfs_printk(KERN_DEBUG, "Valid marker not found\n");
- }
+ } else
+ rc = 0;
out:
return rc;
}
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->metadata_size / 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: 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
*
* Returns zero on success
*/
-static int ecryptfs_write_headers_virt(char *page_virt, size_t *size,
+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)
{
offset = ECRYPTFS_FILE_SIZE_BYTES;
write_ecryptfs_marker((page_virt + offset), &written);
offset += written;
- write_ecryptfs_flags((page_virt + offset), crypt_stat, &written);
+ ecryptfs_write_crypt_stat_flags((page_virt + offset), crypt_stat,
+ &written);
offset += 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);
}
static int
-ecryptfs_write_metadata_to_contents(struct ecryptfs_crypt_stat *crypt_stat,
- struct dentry *ecryptfs_dentry,
- char *page_virt)
+ecryptfs_write_metadata_to_contents(struct dentry *ecryptfs_dentry,
+ char *virt, size_t virt_len)
{
- int current_header_page;
- int header_pages;
int rc;
- rc = ecryptfs_write_lower(ecryptfs_dentry->d_inode, page_virt,
- 0, PAGE_CACHE_SIZE);
- if (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", __FUNCTION__,
- rc);
- goto out;
- }
- header_pages = ((crypt_stat->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) {
- loff_t offset;
-
- offset = (((loff_t)current_header_page) << PAGE_CACHE_SHIFT);
- if ((rc = ecryptfs_write_lower(ecryptfs_dentry->d_inode,
- page_virt, offset,
- PAGE_CACHE_SIZE))) {
- printk(KERN_ERR "%s: Error attempting to write header "
- "information to lower file; rc = [%d]\n",
- __FUNCTION__, rc);
- goto out;
- }
- current_header_page++;
- }
-out:
+ "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,
- struct ecryptfs_crypt_stat *crypt_stat,
char *page_virt, size_t size)
{
int rc;
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_metadata
* @ecryptfs_dentry: The eCryptfs dentry
* retrieved via a prompt. Exactly what happens at this point should
* be policy-dependent.
*
- * TODO: Support header information spanning multiple pages
- *
* Returns zero on success; non-zero on error
*/
int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry)
{
struct ecryptfs_crypt_stat *crypt_stat =
&ecryptfs_inode_to_private(ecryptfs_dentry->d_inode)->crypt_stat;
- char *page_virt;
+ unsigned int order;
+ char *virt;
+ size_t virt_len;
size_t size = 0;
int rc = 0;
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->metadata_size;
+ order = get_order(virt_len);
/* Released in this function */
- page_virt = kmem_cache_zalloc(ecryptfs_header_cache_0, GFP_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;
}
- rc = ecryptfs_write_headers_virt(page_virt, &size, crypt_stat,
- ecryptfs_dentry);
+ 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,
- crypt_stat, page_virt,
+ rc = ecryptfs_write_metadata_to_xattr(ecryptfs_dentry, virt,
size);
else
- rc = ecryptfs_write_metadata_to_contents(crypt_stat,
- ecryptfs_dentry,
- page_virt);
+ rc = ecryptfs_write_metadata_to_contents(ecryptfs_dentry, virt,
+ virt_len);
if (rc) {
- printk(KERN_ERR "Error writing metadata out to lower file; "
- "rc = [%d]\n", rc);
+ printk(KERN_ERR "%s: Error writing metadata out to lower file; "
+ "rc = [%d]\n", __func__, rc);
goto out_free;
}
out_free:
- kmem_cache_free(ecryptfs_header_cache_0, page_virt);
+ free_pages((unsigned long)virt, order);
out:
return rc;
}
u32 header_extent_size;
u16 num_header_extents_at_front;
- memcpy(&header_extent_size, virt, sizeof(u32));
- header_extent_size = be32_to_cpu(header_extent_size);
- virt += sizeof(u32);
- memcpy(&num_header_extents_at_front, virt, sizeof(u16));
- num_header_extents_at_front = be16_to_cpu(num_header_extents_at_front);
- crypt_stat->num_header_extents_at_front =
- (int)num_header_extents_at_front;
- (*bytes_read) = (sizeof(u32) + sizeof(u16));
+ header_extent_size = get_unaligned_be32(virt);
+ virt += sizeof(__be32);
+ num_header_extents_at_front = get_unaligned_be16(virt);
+ crypt_stat->metadata_size = (((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->extent_size
- * crypt_stat->num_header_extents_at_front)
+ && (crypt_stat->metadata_size
< ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE)) {
rc = -EINVAL;
- printk(KERN_WARNING "Invalid number of header extents: [%zd]\n",
- crypt_stat->num_header_extents_at_front);
+ printk(KERN_WARNING "Invalid header size: [%zd]\n",
+ crypt_stat->metadata_size);
}
return rc;
}
*/
static void set_default_header_data(struct ecryptfs_crypt_stat *crypt_stat)
{
- crypt_stat->num_header_extents_at_front = 2;
+ crypt_stat->metadata_size = ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE;
}
/**
size = ecryptfs_getxattr_lower(lower_dentry, ECRYPTFS_XATTR_NAME,
page_virt, ECRYPTFS_DEFAULT_EXTENT_SIZE);
if (size < 0) {
- printk(KERN_ERR "Error attempting to read the [%s] "
- "xattr from the lower file; return value = [%zd]\n",
- ECRYPTFS_XATTR_NAME, size);
+ 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;
}
if (!page_virt) {
rc = -ENOMEM;
printk(KERN_ERR "%s: Unable to allocate page_virt\n",
- __FUNCTION__);
+ __func__);
goto out;
}
rc = ecryptfs_read_lower(page_virt, 0, crypt_stat->extent_size,
ecryptfs_inode);
- if (!rc)
+ if (rc >= 0)
rc = ecryptfs_read_headers_virt(page_virt, crypt_stat,
ecryptfs_dentry,
ECRYPTFS_VALIDATE_HEADER_SIZE);
if (rc) {
+ memset(page_virt, 0, PAGE_CACHE_SIZE);
rc = ecryptfs_read_xattr_region(page_virt, ecryptfs_inode);
if (rc) {
printk(KERN_DEBUG "Valid eCryptfs headers not found in "
}
/**
- * 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
- *
- * 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.
+ * ecryptfs_encrypt_filename - encrypt filename
*
- * 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.
+ * 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.
*
- * 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;
}
/**
char *cipher_name, size_t *key_size)
{
char dummy_key[ECRYPTFS_MAX_KEY_BYTES];
- char *full_alg_name;
+ char *full_alg_name = NULL;
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;
}
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]; rc = [%d]\n", cipher_name, rc);
+ "[%s]; rc = [%d]\n", full_alg_name, rc);
goto out;
}
crypto_blkcipher_set_flags(*key_tfm, CRYPTO_TFM_REQ_WEAK_KEY);
get_random_bytes(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:
+ kfree(full_alg_name);
return rc;
}
struct kmem_cache *ecryptfs_key_tfm_cache;
-struct list_head key_tfm_list;
+static struct list_head key_tfm_list;
struct mutex key_tfm_list_mutex;
int ecryptfs_init_crypto(void)
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;
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;
(*key_tfm) = NULL;
goto out;
}
- mutex_lock(&key_tfm_list_mutex);
list_add(&tmp_tfm->key_tfm_list, &key_tfm_list);
- mutex_unlock(&key_tfm_list_mutex);
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)
(*tfm) = NULL;
(*tfm_mutex) = NULL;
+
mutex_lock(&key_tfm_list_mutex);
- list_for_each_entry(key_tfm, &key_tfm_list, key_tfm_list) {
- if (strcmp(key_tfm->cipher_name, cipher_name) == 0) {
- (*tfm) = key_tfm->key_tfm;
- (*tfm_mutex) = &key_tfm->key_tfm_mutex;
- mutex_unlock(&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);
- 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);
+ 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;
}
- (*tfm) = key_tfm->key_tfm;
- (*tfm_mutex) = &key_tfm->key_tfm_mutex;
+ 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;
}