From 4bdfc873ba34e425d6532581b4127b960274272a Mon Sep 17 00:00:00 2001 From: Michael Halcrow Date: Sun, 12 Apr 2015 00:56:28 -0400 Subject: [PATCH] ext4 crypto: insert encrypted filenames into a leaf directory block Signed-off-by: Uday Savagaonkar Signed-off-by: Ildar Muslukhov Signed-off-by: Michael Halcrow Signed-off-by: Theodore Ts'o --- fs/ext4/ext4.h | 4 ++- fs/ext4/inline.c | 7 +++-- fs/ext4/namei.c | 81 ++++++++++++++++++++++++++++++++++++++++++------ 3 files changed, 79 insertions(+), 13 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index ba75838f3588..5146e67e8d51 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -2151,9 +2151,11 @@ extern int ext4_find_dest_de(struct inode *dir, struct inode *inode, void *buf, int buf_size, const char *name, int namelen, struct ext4_dir_entry_2 **dest_de); -void ext4_insert_dentry(struct inode *inode, +int ext4_insert_dentry(struct inode *dir, + struct inode *inode, struct ext4_dir_entry_2 *de, int buf_size, + const struct qstr *iname, const char *name, int namelen); static inline void ext4_update_dx_flag(struct inode *inode) { diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c index 661f0b8dcfe0..feb2cafbeace 100644 --- a/fs/ext4/inline.c +++ b/fs/ext4/inline.c @@ -11,11 +11,13 @@ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ + +#include + #include "ext4_jbd2.h" #include "ext4.h" #include "xattr.h" #include "truncate.h" -#include #define EXT4_XATTR_SYSTEM_DATA "data" #define EXT4_MIN_INLINE_DATA_SIZE ((sizeof(__le32) * EXT4_N_BLOCKS)) @@ -1014,7 +1016,8 @@ static int ext4_add_dirent_to_inline(handle_t *handle, err = ext4_journal_get_write_access(handle, iloc->bh); if (err) return err; - ext4_insert_dentry(inode, de, inline_size, name, namelen); + ext4_insert_dentry(dir, inode, de, inline_size, &dentry->d_name, + name, namelen); ext4_show_inline_dir(dir, iloc->bh, inline_start, inline_size); diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index 8cef115ee64a..eb11a1b8a3d5 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -1665,19 +1665,49 @@ int ext4_find_dest_de(struct inode *dir, struct inode *inode, return 0; } -void ext4_insert_dentry(struct inode *inode, - struct ext4_dir_entry_2 *de, - int buf_size, - const char *name, int namelen) +int ext4_insert_dentry(struct inode *dir, + struct inode *inode, + struct ext4_dir_entry_2 *de, + int buf_size, + const struct qstr *iname, + const char *name, int namelen) { int nlen, rlen; + struct ext4_fname_crypto_ctx *ctx = NULL; + struct ext4_str fname_crypto_str = {.name = NULL, .len = 0}; + struct ext4_str tmp_str; + int res; + + ctx = ext4_get_fname_crypto_ctx(dir, EXT4_NAME_LEN); + if (IS_ERR(ctx)) + return -EIO; + /* By default, the input name would be written to the disk */ + tmp_str.name = (unsigned char *)name; + tmp_str.len = namelen; + if (ctx != NULL) { + /* Directory is encrypted */ + res = ext4_fname_crypto_alloc_buffer(ctx, EXT4_NAME_LEN, + &fname_crypto_str); + if (res < 0) { + ext4_put_fname_crypto_ctx(&ctx); + return -ENOMEM; + } + res = ext4_fname_usr_to_disk(ctx, iname, &fname_crypto_str); + if (res < 0) { + ext4_put_fname_crypto_ctx(&ctx); + ext4_fname_crypto_free_buffer(&fname_crypto_str); + return res; + } + tmp_str.name = fname_crypto_str.name; + tmp_str.len = fname_crypto_str.len; + } nlen = EXT4_DIR_REC_LEN(de->name_len); rlen = ext4_rec_len_from_disk(de->rec_len, buf_size); if (de->inode) { struct ext4_dir_entry_2 *de1 = - (struct ext4_dir_entry_2 *)((char *)de + nlen); + (struct ext4_dir_entry_2 *)((char *)de + nlen); de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, buf_size); de->rec_len = ext4_rec_len_to_disk(nlen, buf_size); de = de1; @@ -1685,9 +1715,14 @@ void ext4_insert_dentry(struct inode *inode, de->file_type = EXT4_FT_UNKNOWN; de->inode = cpu_to_le32(inode->i_ino); ext4_set_de_type(inode->i_sb, de, inode->i_mode); - de->name_len = namelen; - memcpy(de->name, name, namelen); + de->name_len = tmp_str.len; + + memcpy(de->name, tmp_str.name, tmp_str.len); + ext4_put_fname_crypto_ctx(&ctx); + ext4_fname_crypto_free_buffer(&fname_crypto_str); + return 0; } + /* * Add a new entry into a directory (leaf) block. If de is non-NULL, * it points to a directory entry which is guaranteed to be large @@ -1724,8 +1759,12 @@ static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry, return err; } - /* By now the buffer is marked for journaling */ - ext4_insert_dentry(inode, de, blocksize, name, namelen); + /* By now the buffer is marked for journaling. Due to crypto operations, + * the following function call may fail */ + err = ext4_insert_dentry(dir, inode, de, blocksize, &dentry->d_name, + name, namelen); + if (err < 0) + return err; /* * XXX shouldn't update any times until successful @@ -1757,8 +1796,13 @@ static int make_indexed_dir(handle_t *handle, struct dentry *dentry, struct inode *inode, struct buffer_head *bh) { struct inode *dir = dentry->d_parent->d_inode; +#ifdef CONFIG_EXT4_FS_ENCRYPTION + struct ext4_fname_crypto_ctx *ctx = NULL; + int res; +#else const char *name = dentry->d_name.name; int namelen = dentry->d_name.len; +#endif struct buffer_head *bh2; struct dx_root *root; struct dx_frame frames[2], *frame; @@ -1772,7 +1816,13 @@ static int make_indexed_dir(handle_t *handle, struct dentry *dentry, struct dx_hash_info hinfo; ext4_lblk_t block; struct fake_dirent *fde; - int csum_size = 0; + int csum_size = 0; + +#ifdef CONFIG_EXT4_FS_ENCRYPTION + ctx = ext4_get_fname_crypto_ctx(dir, EXT4_NAME_LEN); + if (IS_ERR(ctx)) + return PTR_ERR(ctx); +#endif if (ext4_has_metadata_csum(inode->i_sb)) csum_size = sizeof(struct ext4_dir_entry_tail); @@ -1839,7 +1889,18 @@ static int make_indexed_dir(handle_t *handle, struct dentry *dentry, if (hinfo.hash_version <= DX_HASH_TEA) hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned; hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed; +#ifdef CONFIG_EXT4_FS_ENCRYPTION + res = ext4_fname_usr_to_hash(ctx, &dentry->d_name, &hinfo); + if (res < 0) { + ext4_put_fname_crypto_ctx(&ctx); + ext4_mark_inode_dirty(handle, dir); + brelse(bh); + return res; + } + ext4_put_fname_crypto_ctx(&ctx); +#else ext4fs_dirhash(name, namelen, &hinfo); +#endif memset(frames, 0, sizeof(frames)); frame = frames; frame->entries = entries; -- 2.20.1