[PATCH 1/8] crypto: hash: add zero length message hash for shax and md5

[LABBE Corentin <clabbe.montjoie@gmail.com>]

Some crypto drivers cannot process empty data message and return a
precalculated hash for md5/sha1/sha224/sha256.

This patch add thoses precalculated hash in include/crypto.

Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com>
---
 include/crypto/md5.h |  5 +++++
 include/crypto/sha.h | 20 ++++++++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/include/crypto/md5.h b/include/crypto/md5.h
index 146af82..6496ee0 100644
--- a/include/crypto/md5.h
+++ b/include/crypto/md5.h
@@ -13,6 +13,11 @@
 #define MD5_H2	0x98badcfeUL
 #define MD5_H3	0x10325476UL
 
+static const u8 md5_zero_message_hash[MD5_DIGEST_SIZE] = {
+	0xd4, 0x1d, 0x8c, 0xd9, 0x8f, 0x00, 0xb2, 0x04,
+	0xe9, 0x80, 0x09, 0x98, 0xec, 0xf8, 0x42, 0x7e,
+};
+
 struct md5_state {
 	u32 hash[MD5_HASH_WORDS];
 	u32 block[MD5_BLOCK_WORDS];
diff --git a/include/crypto/sha.h b/include/crypto/sha.h
index dd7905a..02d7ffb 100644
--- a/include/crypto/sha.h
+++ b/include/crypto/sha.h
@@ -64,6 +64,26 @@
 #define SHA512_H6	0x1f83d9abfb41bd6bULL
 #define SHA512_H7	0x5be0cd19137e2179ULL
 
+static const u8 sha1_zero_message_hash[SHA1_DIGEST_SIZE] = {
+	0xda, 0x39, 0xa3, 0xee, 0x5e, 0x6b, 0x4b, 0x0d,
+	0x32, 0x55, 0xbf, 0xef, 0x95, 0x60, 0x18, 0x90,
+	0xaf, 0xd8, 0x07, 0x09
+};
+
+static const u8 sha224_zero_message_hash[SHA224_DIGEST_SIZE] = {
+	0xd1, 0x4a, 0x02, 0x8c, 0x2a, 0x3a, 0x2b, 0xc9, 0x47,
+	0x61, 0x02, 0xbb, 0x28, 0x82, 0x34, 0xc4, 0x15, 0xa2,
+	0xb0, 0x1f, 0x82, 0x8e, 0xa6, 0x2a, 0xc5, 0xb3, 0xe4,
+	0x2f
+};
+
+static const u8 sha256_zero_message_hash[SHA256_DIGEST_SIZE] = {
+	0xe3, 0xb0, 0xc4, 0x42, 0x98, 0xfc, 0x1c, 0x14,
+	0x9a, 0xfb, 0xf4, 0xc8, 0x99, 0x6f, 0xb9, 0x24,
+	0x27, 0xae, 0x41, 0xe4, 0x64, 0x9b, 0x93, 0x4c,
+	0xa4, 0x95, 0x99, 0x1b, 0x78, 0x52, 0xb8, 0x55
+};
+
 struct sha1_state {
 	u32 state[SHA1_DIGEST_SIZE / 4];
 	u64 count;
-- 
2.4.9