From: Eric Biggers <ebiggers@xxxxxxxxxx>
Add SHA-512 support to fs-verity. This is primarily a demonstration of
the trivial changes needed to support a new hash algorithm in fs-verity;
most users will still use SHA-256, due to the smaller space required to
store the hashes. But some users may prefer SHA-512.
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
---
fs/verity/fsverity_private.h | 2 +-
fs/verity/hash_algs.c | 5 +++++
include/uapi/linux/fsverity.h | 1 +
3 files changed, 7 insertions(+), 1 deletion(-)
diff --git a/fs/verity/fsverity_private.h b/fs/verity/fsverity_private.h
index d61ad740027d..693ef030adbe 100644
--- a/fs/verity/fsverity_private.h
+++ b/fs/verity/fsverity_private.h
@@ -31,7 +31,7 @@ struct ahash_request;
* Largest digest size among all hash algorithms supported by fs-verity.
* Currently assumed to be <= size of fsverity_descriptor::root_hash.
*/
-#define FS_VERITY_MAX_DIGEST_SIZE SHA256_DIGEST_SIZE
+#define FS_VERITY_MAX_DIGEST_SIZE SHA512_DIGEST_SIZE
/* A hash algorithm supported by fs-verity */
struct fsverity_hash_alg {
diff --git a/fs/verity/hash_algs.c b/fs/verity/hash_algs.c
index 46df17094fc2..e0462a010cab 100644
--- a/fs/verity/hash_algs.c
+++ b/fs/verity/hash_algs.c
@@ -17,6 +17,11 @@ struct fsverity_hash_alg fsverity_hash_algs[] = {
.digest_size = SHA256_DIGEST_SIZE,
.block_size = SHA256_BLOCK_SIZE,
},
+ [FS_VERITY_HASH_ALG_SHA512] = {
+ .name = "sha512",
+ .digest_size = SHA512_DIGEST_SIZE,
+ .block_size = SHA512_BLOCK_SIZE,
+ },
};
/**
diff --git a/include/uapi/linux/fsverity.h b/include/uapi/linux/fsverity.h
index 57d1d7fc0c34..da0daf6c193b 100644
--- a/include/uapi/linux/fsverity.h
+++ b/include/uapi/linux/fsverity.h
@@ -14,6 +14,7 @@
#include <linux/types.h>
#define FS_VERITY_HASH_ALG_SHA256 1
+#define FS_VERITY_HASH_ALG_SHA512 2
struct fsverity_enable_arg {
__u32 version;
--
2.21.0
