summaryrefslogtreecommitdiffstats
path: root/fs/ext4/crypto.c
diff options
context:
space:
mode:
authorRitesh Harjani <ritesh.list@gmail.com>2022-05-15 08:37:48 +0200
committerTheodore Ts'o <tytso@mit.edu>2022-05-22 04:24:24 +0200
commit72f63f4a770310233dba3bff8fc6e41660ebaa27 (patch)
tree6c9faa859341418cce505759bb9e088a41500c45 /fs/ext4/crypto.c
parentext4: cleanup function defs from ext4.h into crypto.c (diff)
downloadlinux-72f63f4a770310233dba3bff8fc6e41660ebaa27.tar.xz
linux-72f63f4a770310233dba3bff8fc6e41660ebaa27.zip
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.c54
1 files changed, 54 insertions, 0 deletions
diff --git a/fs/ext4/crypto.c b/fs/ext4/crypto.c
index f8333927f0f6..e20ac0654b3f 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,