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| author | Ritesh Harjani <ritesh.list@gmail.com> | 2022-05-15 12:07:48 +0530 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2022-05-21 22:24:24 -0400 |
| commit | 72f63f4a770310233dba3bff8fc6e41660ebaa27 (patch) | |
| tree | 6c9faa859341418cce505759bb9e088a41500c45 /fs/ext4/crypto.c | |
| parent | 3030b59c8533835f4e8b5e6d7047f80dcf7e40b9 (diff) | |
| download | linux-72f63f4a770310233dba3bff8fc6e41660ebaa27.tar.gz | |
ext4: refactor and move ext4_ioctl_get_encryption_pwsalt()
This patch move code for FS_IOC_GET_ENCRYPTION_PWSALT case into
ext4's crypto.c file, i.e. ext4_ioctl_get_encryption_pwsalt()
and uuid_is_zero(). This is mostly refactoring logic and should
not affect any functionality change.
Suggested-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Ritesh Harjani <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/5af98b17152a96b245b4f7d2dfb8607fc93e36aa.1652595565.git.ritesh.list@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Diffstat (limited to 'fs/ext4/crypto.c')
| -rw-r--r-- | fs/ext4/crypto.c | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/fs/ext4/crypto.c b/fs/ext4/crypto.c index f8333927f0f67..e20ac0654b3f2 100644 --- a/fs/ext4/crypto.c +++ b/fs/ext4/crypto.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0 #include <linux/quotaops.h> +#include <linux/uuid.h> #include "ext4.h" #include "xattr.h" @@ -71,6 +72,59 @@ void ext4_fname_free_filename(struct ext4_filename *fname) #endif } +static bool uuid_is_zero(__u8 u[16]) +{ + int i; + + for (i = 0; i < 16; i++) + if (u[i]) + return false; + return true; +} + +int ext4_ioctl_get_encryption_pwsalt(struct file *filp, void __user *arg) +{ + struct super_block *sb = file_inode(filp)->i_sb; + struct ext4_sb_info *sbi = EXT4_SB(sb); + int err, err2; + handle_t *handle; + + if (!ext4_has_feature_encrypt(sb)) + return -EOPNOTSUPP; + + if (uuid_is_zero(sbi->s_es->s_encrypt_pw_salt)) { + err = mnt_want_write_file(filp); + if (err) + return err; + handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1); + if (IS_ERR(handle)) { + err = PTR_ERR(handle); + goto pwsalt_err_exit; + } + err = ext4_journal_get_write_access(handle, sb, sbi->s_sbh, + EXT4_JTR_NONE); + if (err) + goto pwsalt_err_journal; + lock_buffer(sbi->s_sbh); + generate_random_uuid(sbi->s_es->s_encrypt_pw_salt); + ext4_superblock_csum_set(sb); + unlock_buffer(sbi->s_sbh); + err = ext4_handle_dirty_metadata(handle, NULL, sbi->s_sbh); +pwsalt_err_journal: + err2 = ext4_journal_stop(handle); + if (err2 && !err) + err = err2; +pwsalt_err_exit: + mnt_drop_write_file(filp); + if (err) + return err; + } + + if (copy_to_user(arg, sbi->s_es->s_encrypt_pw_salt, 16)) + return -EFAULT; + return 0; +} + static int ext4_get_context(struct inode *inode, void *ctx, size_t len) { return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION, |