From f4e60e6b303bc46cdc477d3174dbf9cb5dd013aa Mon Sep 17 00:00:00 2001 From: Tyler Hicks Date: Thu, 11 Feb 2010 00:02:32 -0600 Subject: [PATCH] eCryptfs: Strip metadata in xattr flag in encrypted view The ecryptfs_encrypted_view mount option provides a unified way of viewing encrypted eCryptfs files. If the metadata is stored in a xattr, the metadata is moved to the file header when the file is read inside the eCryptfs mount. Because of this, we should strip the ECRYPTFS_METADATA_IN_XATTR flag from the header's flag section. This allows eCryptfs to treat the file as an eCryptfs file with a header at the front. Reviewed-by: Eric Sandeen Signed-off-by: Tyler Hicks --- fs/ecryptfs/crypto.c | 9 +++++---- fs/ecryptfs/ecryptfs_kernel.h | 3 +++ fs/ecryptfs/mmap.c | 14 ++++++++++++++ 3 files changed, 22 insertions(+), 4 deletions(-) diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c index 4d9db0ed88e..fad5bf6a611 100644 --- a/fs/ecryptfs/crypto.c +++ b/fs/ecryptfs/crypto.c @@ -1107,9 +1107,9 @@ static void write_ecryptfs_marker(char *page_virt, size_t *written) (*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; @@ -1290,7 +1290,8 @@ static int ecryptfs_write_headers_virt(char *page_virt, size_t max, 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); diff --git a/fs/ecryptfs/ecryptfs_kernel.h b/fs/ecryptfs/ecryptfs_kernel.h index d031efd7666..bc7115403f3 100644 --- a/fs/ecryptfs/ecryptfs_kernel.h +++ b/fs/ecryptfs/ecryptfs_kernel.h @@ -659,6 +659,9 @@ int ecryptfs_decrypt_page(struct page *page); int ecryptfs_write_metadata(struct dentry *ecryptfs_dentry); int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry); int ecryptfs_new_file_context(struct dentry *ecryptfs_dentry); +void ecryptfs_write_crypt_stat_flags(char *page_virt, + struct ecryptfs_crypt_stat *crypt_stat, + size_t *written); int ecryptfs_read_and_validate_header_region(char *data, struct inode *ecryptfs_inode); int ecryptfs_read_and_validate_xattr_region(char *page_virt, diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c index 270f42ae7c0..bea998a25af 100644 --- a/fs/ecryptfs/mmap.c +++ b/fs/ecryptfs/mmap.c @@ -82,6 +82,19 @@ out: return rc; } +static void strip_xattr_flag(char *page_virt, + struct ecryptfs_crypt_stat *crypt_stat) +{ + if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) { + size_t written; + + crypt_stat->flags &= ~ECRYPTFS_METADATA_IN_XATTR; + ecryptfs_write_crypt_stat_flags(page_virt, crypt_stat, + &written); + crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR; + } +} + /** * Header Extent: * Octets 0-7: Unencrypted file size (big-endian) @@ -136,6 +149,7 @@ ecryptfs_copy_up_encrypted_with_header(struct page *page, rc = ecryptfs_read_xattr_region( page_virt, page->mapping->host); + strip_xattr_flag(page_virt + 16, crypt_stat); ecryptfs_write_header_metadata(page_virt + 20, crypt_stat, &written); -- 2.39.3