ext4 crypto: reserve codepoints used by the ext4 encryption feature

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

1 files changed, 13 insertions, 3 deletions

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index f7f3f5871796..e1683829b2b5 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -422,7 +422,7 @@ enum {
         EXT4_INODE_DIRTY        = 8,
         EXT4_INODE_COMPRBLK     = 9,    /* One or more compressed clusters */
         EXT4_INODE_NOCOMPR      = 10,   /* Don't compress */
-        EXT4_INODE_ENCRYPT      = 11,   /* Compression error */
+        EXT4_INODE_ENCRYPT      = 11,   /* Encrypted file */
 /* End compression flags --- maybe not all used */
         EXT4_INODE_INDEX        = 12,   /* hash-indexed directory */
         EXT4_INODE_IMAGIC       = 13,   /* AFS directory */
@@ -582,6 +582,13 @@ enum {
 #define EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER   0x0010
 #define EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER    0x0020
 
+/* Encryption algorithms */
+#define EXT4_ENCRYPTION_MODE_INVALID            0
+#define EXT4_ENCRYPTION_MODE_AES_256_XTS        1
+#define EXT4_ENCRYPTION_MODE_AES_256_GCM        2
+#define EXT4_ENCRYPTION_MODE_AES_256_CBC        3
+#define EXT4_ENCRYPTION_MODE_AES_256_CTS        4
+
 /*
  * ioctl commands
  */
@@ -1142,7 +1149,8 @@ struct ext4_super_block {
         __le32  s_raid_stripe_width;    /* blocks on all data disks (N*stride)*/
         __u8    s_log_groups_per_flex;  /* FLEX_BG group size */
         __u8    s_checksum_type;        /* metadata checksum algorithm used */
-        __le16  s_reserved_pad;
+        __u8    s_encryption_level;     /* versioning level for encryption */
+        __u8    s_reserved_pad;         /* Padding to next 32bits */
         __le64  s_kbytes_written;       /* nr of lifetime kilobytes written */
         __le32  s_snapshot_inum;        /* Inode number of active snapshot */
         __le32  s_snapshot_id;          /* sequential ID of active snapshot */
@@ -1169,7 +1177,9 @@ struct ext4_super_block {
         __le32  s_overhead_clusters;    /* overhead blocks/clusters in fs */
         __le32  s_backup_bgs[2];        /* groups with sparse_super2 SBs */
         __u8    s_encrypt_algos[4];     /* Encryption algorithms in use  */
-        __le32  s_reserved[105];        /* Padding to the end of the block */
+        __u8    s_encrypt_pw_salt[16];  /* Salt used for string2key algorithm */
+        __le32  s_lpf_ino;              /* Location of the lost+found inode */
+        __le32  s_reserved[100];        /* Padding to the end of the block */
         __le32  s_checksum;             /* crc32c(superblock) */
 };