void sha256_csum_wd(const unsigned char *input, unsigned int ilen,
unsigned char *output, unsigned int chunk_sz);
+void sha256_hmac(const unsigned char *key, int keylen,
+ const unsigned char *input, unsigned int ilen,
+ unsigned char *output);
#endif /* _SHA256_H */
sha256_finish(&ctx, output);
}
+
+/*
+ * Output = HMAC-SHA-256( input buffer, hmac key )
+ */
+void sha256_hmac(const unsigned char *key, int keylen,
+ const unsigned char *input, unsigned int ilen,
+ unsigned char *output)
+{
+ int i;
+ sha256_context ctx;
+ unsigned char k_ipad[64];
+ unsigned char k_opad[64];
+ unsigned char tmpbuf[32];
+
+ memset (k_ipad, 0x36, 64);
+ memset (k_opad, 0x5C, 64);
+
+ for (i = 0; i < keylen; i++) {
+ if (i >= 64)
+ break;
+
+ k_ipad[i] ^= key[i];
+ k_opad[i] ^= key[i];
+ }
+
+ sha256_starts (&ctx);
+ sha256_update (&ctx, k_ipad, 64);
+ sha256_update (&ctx, input, ilen);
+ sha256_finish (&ctx, tmpbuf);
+
+ sha256_starts (&ctx);
+ sha256_update (&ctx, k_opad, 64);
+ sha256_update (&ctx, tmpbuf, 32);
+ sha256_finish (&ctx, output);
+
+ memset (k_ipad, 0, 64);
+ memset (k_opad, 0, 64);
+ memset (tmpbuf, 0, 32);
+ memset (&ctx, 0, sizeof (sha256_context));
+}