[PATCH] crypto: mscode_parser: remove sha224 authenticode support

[Dimitri John Ledkov <dimitri.ledkov@canonical.com>]

It is possible to stand up own certificates and sign PE-COFF binaries
using SHA-224. However it never became popular or needed since it has
similar costs as SHA-256. Windows Authenticode infrastructure never
had support for SHA-224, and all secureboot keys used fro linux
vmlinuz have always been using at least SHA-256.

Given the point of mscode_parser is to support interoperatiblity with
typical de-facto hashes, remove support for SHA-224 to avoid
posibility of creating interoperatibility issues with rhboot/shim,
grub, and non-linux systems trying to sign or verify vmlinux.

SHA-224 itself is not removed from the kernel, as it is truncated
SHA-256. If requested I can write patches to remove SHA-224 support
across all of the drivers.

Signed-off-by: Dimitri John Ledkov <dimitri.ledkov@canonical.com>
---
 crypto/asymmetric_keys/mscode_parser.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/crypto/asymmetric_keys/mscode_parser.c b/crypto/asymmetric_keys/mscode_parser.c
index 6416bded0e..855cbc46a9 100644
--- a/crypto/asymmetric_keys/mscode_parser.c
+++ b/crypto/asymmetric_keys/mscode_parser.c
@@ -84,9 +84,6 @@ int mscode_note_digest_algo(void *context, size_t hdrlen,
 	case OID_sha512:
 		ctx->digest_algo = "sha512";
 		break;
-	case OID_sha224:
-		ctx->digest_algo = "sha224";
-		break;
 
 	case OID__NR:
 		sprint_oid(value, vlen, buffer, sizeof(buffer));
-- 
2.34.1