author: Daniel Rosenberg <drosen@google.com> 2021-03-19 07:34:13 +0000
committer: Theodore Ts'o <tytso@mit.edu> 2021-04-05 22:04:20 -0400
commit: 471fbbea7ff7061b2d6474665cb5a2ceb4fd6500
parent: 400086d7c11327cfe1b1aa4487adceb41e82b4df
Commit Summary:
Diffstat:
1 file changed, 19 insertions, 4 deletions
diff --git a/fs/ext4/hash.c b/fs/ext4/hash.c
index a92eb79de0cc..f34f4176c1e7 100644
--- a/fs/ext4/hash.c
+++ b/fs/ext4/hash.c
@@ -197,7 +197,7 @@ static void str2hashbuf_unsigned(const char *msg, int len, __u32 *buf, int num)
* represented, and whether or not the returned hash is 32 bits or 64
* bits. 32 bit hashes will return 0 for the minor hash.
*/
-static int __ext4fs_dirhash(const char *name, int len,
+static int __ext4fs_dirhash(const struct inode *dir, const char *name, int len,
struct dx_hash_info *hinfo)
{
__u32 hash;
@@ -259,6 +259,22 @@ static int __ext4fs_dirhash(const char *name, int len,
hash = buf[0];
minor_hash = buf[1];
break;
+ case DX_HASH_SIPHASH:
+ {
+ struct qstr qname = QSTR_INIT(name, len);
+ __u64 combined_hash;
+
+ if (fscrypt_has_encryption_key(dir)) {
+ combined_hash = fscrypt_fname_siphash(dir, &qname);
+ } else {
+ ext4_warning_inode(dir, "Siphash requires key");
+ return -1;
+ }
+
+ hash = (__u32)(combined_hash >> 32);
+ minor_hash = (__u32)combined_hash;
+ break;
+ }
default:
hinfo->hash = 0;
return -1;
@@ -280,7 +296,8 @@ int ext4fs_dirhash(const struct inode *dir, const char *name, int len,
unsigned char *buff;
struct qstr qstr = {.name = name, .len = len };
- if (len && IS_CASEFOLDED(dir) && um) {
+ if (len && IS_CASEFOLDED(dir) && um &&
+ (!IS_ENCRYPTED(dir) || fscrypt_has_encryption_key(dir))) {
buff = kzalloc(sizeof(char) * PATH_MAX, GFP_KERNEL);
if (!buff)
return -ENOMEM;
@@ -291,12 +308,12 @@ int ext4fs_dirhash(const struct inode *dir, const char *name, int len,
goto opaque_seq;
}
- r = __ext4fs_dirhash(buff, dlen, hinfo);
+ r = __ext4fs_dirhash(dir, buff, dlen, hinfo);
kfree(buff);
return r;
}
opaque_seq:
#endif
- return __ext4fs_dirhash(name, len, hinfo);
+ return __ext4fs_dirhash(dir, name, len, hinfo);
}