[CRYPTO] sha256-generic: Extend sha256_generic.c to support SHA-224

Resubmitting this patch which extends sha256_generic.c to support SHA-224 as
described in FIPS 180-2 and RFC 3874. HMAC-SHA-224 as described in RFC4231
is then supported through the hmac interface.

Patch includes test vectors for SHA-224 and HMAC-SHA-224.

SHA-224 chould be chosen as a hash algorithm when 112 bits of security
strength is required.

Patch generated against the 2.6.24-rc1 kernel and tested against
2.6.24-rc1-git14 which includes fix for scatter gather implementation for HMAC.

Signed-off-by: Jonathan Lynch <jonathan.lynch@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/include/crypto/sha.h b/include/crypto/sha.h
index 0686e1f..c0ccc2b 100644
--- a/include/crypto/sha.h
+++ b/include/crypto/sha.h
@@ -8,6 +8,9 @@
 #define SHA1_DIGEST_SIZE        20
 #define SHA1_BLOCK_SIZE         64
 
+#define SHA224_DIGEST_SIZE	28
+#define SHA224_BLOCK_SIZE	64
+
 #define SHA256_DIGEST_SIZE      32
 #define SHA256_BLOCK_SIZE       64
 
@@ -23,6 +26,15 @@
 #define SHA1_H3		0x10325476UL
 #define SHA1_H4		0xc3d2e1f0UL
 
+#define SHA224_H0	0xc1059ed8UL
+#define SHA224_H1	0x367cd507UL
+#define SHA224_H2	0x3070dd17UL
+#define SHA224_H3	0xf70e5939UL
+#define SHA224_H4	0xffc00b31UL
+#define SHA224_H5	0x68581511UL
+#define SHA224_H6	0x64f98fa7UL
+#define SHA224_H7	0xbefa4fa4UL
+
 #define SHA256_H0	0x6a09e667UL
 #define SHA256_H1	0xbb67ae85UL
 #define SHA256_H2	0x3c6ef372UL