Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux
[pandora-kernel.git] / fs / ecryptfs / crypto.c
index b8d5c80..2a83425 100644 (file)
@@ -967,7 +967,7 @@ static void ecryptfs_set_default_crypt_stat_vals(
 
 /**
  * ecryptfs_new_file_context
- * @ecryptfs_dentry: The eCryptfs dentry
+ * @ecryptfs_inode: The eCryptfs inode
  *
  * If the crypto context for the file has not yet been established,
  * this is where we do that.  Establishing a new crypto context
@@ -984,13 +984,13 @@ static void ecryptfs_set_default_crypt_stat_vals(
  *
  * Returns zero on success; non-zero otherwise
  */
-int ecryptfs_new_file_context(struct dentry *ecryptfs_dentry)
+int ecryptfs_new_file_context(struct inode *ecryptfs_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_inode->i_sb)->mount_crypt_stat;
        int cipher_name_len;
        int rc = 0;
 
@@ -1024,25 +1024,25 @@ out:
 }
 
 /**
- * contains_ecryptfs_marker - check for the ecryptfs marker
+ * ecryptfs_validate_marker - check for the ecryptfs marker
  * @data: The data block in which to check
  *
- * Returns one if marker found; zero if not found
+ * Returns zero if marker found; -EINVAL if not found
  */
-static int contains_ecryptfs_marker(char *data)
+static int ecryptfs_validate_marker(char *data)
 {
        u32 m_1, 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;
+               return 0;
        ecryptfs_printk(KERN_DEBUG, "m_1 = [0x%.8x]; m_2 = [0x%.8x]; "
                        "MAGIC_ECRYPTFS_MARKER = [0x%.8x]\n", m_1, m_2,
                        MAGIC_ECRYPTFS_MARKER);
        ecryptfs_printk(KERN_DEBUG, "(m_1 ^ MAGIC_ECRYPTFS_MARKER) = "
                        "[0x%.8x]\n", (m_1 ^ MAGIC_ECRYPTFS_MARKER));
-       return 0;
+       return -EINVAL;
 }
 
 struct ecryptfs_flag_map_elem {
@@ -1201,27 +1201,19 @@ int ecryptfs_cipher_code_to_string(char *str, u8 cipher_code)
        return rc;
 }
 
-int ecryptfs_read_and_validate_header_region(char *data,
-                                            struct inode *ecryptfs_inode)
+int ecryptfs_read_and_validate_header_region(struct inode *inode)
 {
-       struct ecryptfs_crypt_stat *crypt_stat =
-               &(ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat);
+       u8 file_size[ECRYPTFS_SIZE_AND_MARKER_BYTES];
+       u8 *marker = file_size + ECRYPTFS_FILE_SIZE_BYTES;
        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 < 0) {
-               printk(KERN_ERR "%s: Error reading header region; rc = [%d]\n",
-                      __func__, rc);
-               goto out;
-       }
-       if (!contains_ecryptfs_marker(data + ECRYPTFS_FILE_SIZE_BYTES)) {
-               rc = -EINVAL;
-       } else
-               rc = 0;
-out:
+       rc = ecryptfs_read_lower(file_size, 0, ECRYPTFS_SIZE_AND_MARKER_BYTES,
+                                inode);
+       if (rc < ECRYPTFS_SIZE_AND_MARKER_BYTES)
+               return rc >= 0 ? -EINVAL : rc;
+       rc = ecryptfs_validate_marker(marker);
+       if (!rc)
+               ecryptfs_i_size_init(file_size, inode);
        return rc;
 }
 
@@ -1242,8 +1234,7 @@ ecryptfs_write_header_metadata(char *virt,
        (*written) = 6;
 }
 
-struct kmem_cache *ecryptfs_header_cache_1;
-struct kmem_cache *ecryptfs_header_cache_2;
+struct kmem_cache *ecryptfs_header_cache;
 
 /**
  * ecryptfs_write_headers_virt
@@ -1308,12 +1299,12 @@ static int ecryptfs_write_headers_virt(char *page_virt, size_t max,
 }
 
 static int
-ecryptfs_write_metadata_to_contents(struct dentry *ecryptfs_dentry,
+ecryptfs_write_metadata_to_contents(struct inode *ecryptfs_inode,
                                    char *virt, size_t virt_len)
 {
        int rc;
 
-       rc = ecryptfs_write_lower(ecryptfs_dentry->d_inode, virt,
+       rc = ecryptfs_write_lower(ecryptfs_inode, virt,
                                  0, virt_len);
        if (rc < 0)
                printk(KERN_ERR "%s: Error attempting to write header "
@@ -1347,7 +1338,8 @@ static unsigned long ecryptfs_get_zeroed_pages(gfp_t gfp_mask,
 
 /**
  * ecryptfs_write_metadata
- * @ecryptfs_dentry: The eCryptfs dentry
+ * @ecryptfs_dentry: The eCryptfs dentry, which should be negative
+ * @ecryptfs_inode: The newly created eCryptfs inode
  *
  * Write the file headers out.  This will likely involve a userspace
  * callout, in which the session key is encrypted with one or more
@@ -1357,10 +1349,11 @@ static unsigned long ecryptfs_get_zeroed_pages(gfp_t gfp_mask,
  *
  * Returns zero on success; non-zero on error
  */
-int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry)
+int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry,
+                           struct inode *ecryptfs_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;
        unsigned int order;
        char *virt;
        size_t virt_len;
@@ -1400,7 +1393,7 @@ int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry)
                rc = ecryptfs_write_metadata_to_xattr(ecryptfs_dentry, virt,
                                                      size);
        else
-               rc = ecryptfs_write_metadata_to_contents(ecryptfs_dentry, virt,
+               rc = ecryptfs_write_metadata_to_contents(ecryptfs_inode, virt,
                                                         virt_len);
        if (rc) {
                printk(KERN_ERR "%s: Error writing metadata out to lower file; "
@@ -1496,11 +1489,9 @@ static int ecryptfs_read_headers_virt(char *page_virt,
        crypt_stat->mount_crypt_stat = &ecryptfs_superblock_to_private(
                ecryptfs_dentry->d_sb)->mount_crypt_stat;
        offset = ECRYPTFS_FILE_SIZE_BYTES;
-       rc = contains_ecryptfs_marker(page_virt + offset);
-       if (rc == 0) {
-               rc = -EINVAL;
+       rc = ecryptfs_validate_marker(page_virt + offset);
+       if (rc)
                goto out;
-       }
        if (!(crypt_stat->flags & ECRYPTFS_I_SIZE_INITIALIZED))
                ecryptfs_i_size_init(page_virt, ecryptfs_dentry->d_inode);
        offset += MAGIC_ECRYPTFS_MARKER_SIZE_BYTES;
@@ -1567,20 +1558,21 @@ out:
        return rc;
 }
 
-int ecryptfs_read_and_validate_xattr_region(char *page_virt,
-                                           struct dentry *ecryptfs_dentry)
+int ecryptfs_read_and_validate_xattr_region(struct dentry *dentry,
+                                           struct inode *inode)
 {
+       u8 file_size[ECRYPTFS_SIZE_AND_MARKER_BYTES];
+       u8 *marker = file_size + ECRYPTFS_FILE_SIZE_BYTES;
        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:
+       rc = ecryptfs_getxattr_lower(ecryptfs_dentry_to_lower(dentry),
+                                    ECRYPTFS_XATTR_NAME, file_size,
+                                    ECRYPTFS_SIZE_AND_MARKER_BYTES);
+       if (rc < ECRYPTFS_SIZE_AND_MARKER_BYTES)
+               return rc >= 0 ? -EINVAL : rc;
+       rc = ecryptfs_validate_marker(marker);
+       if (!rc)
+               ecryptfs_i_size_init(file_size, inode);
        return rc;
 }
 
@@ -1610,7 +1602,7 @@ int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry)
        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, GFP_USER);
+       page_virt = kmem_cache_alloc(ecryptfs_header_cache, GFP_USER);
        if (!page_virt) {
                rc = -ENOMEM;
                printk(KERN_ERR "%s: Unable to allocate page_virt\n",
@@ -1655,7 +1647,7 @@ int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry)
 out:
        if (page_virt) {
                memset(page_virt, 0, PAGE_CACHE_SIZE);
-               kmem_cache_free(ecryptfs_header_cache_1, page_virt);
+               kmem_cache_free(ecryptfs_header_cache, page_virt);
        }
        return rc;
 }
@@ -1953,7 +1945,7 @@ static unsigned char *portable_filename_chars = ("-.0123456789ABCD"
 
 /* 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[] = {
+static const unsigned char filename_rev_map[256] = {
        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 */
@@ -1969,7 +1961,7 @@ static const unsigned char filename_rev_map[] = {
        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
+       0x3D, 0x3E, 0x3F /* 123 - 255 initialized to 0x00 */
 };
 
 /**