hash: implement SHA-{224,256}

Add the HMAC and Wycheproof bits for HMAC while at it.

auth_hmac.c

@@ -21,6 +21,7 @@
 #include "hash.h"
 #include "auth_hmac.h"
 #include "impl_hmac.h"
+#include "impl_sha256.h"
 #include "impl_sha512.h"
 
 #include "util.h"
@@ -57,6 +58,16 @@ hmac_common_init(void *arg, const uint8_t *key, size_t keylen)
 	    lc_hash_update(ctx->hctx, ikeypad, ctx->blocksz);
 }
 
+int
+hmac_sha224_sha256_init(void *arg, const uint8_t *key, size_t keylen)
+{
+	struct hmac_ctx	*ctx = arg;
+
+	ctx->blocksz = SHA256_CHUNK;
+
+	return hmac_common_init(ctx, key, keylen);
+}
+
 int
 hmac_sha384_sha512_init(void *arg, const uint8_t *key, size_t keylen)
 {
@@ -124,6 +135,18 @@ hmac_common_ctx_new(const struct lc_hash_impl *impl)
 	return ctx;
 }
 
+static void *
+hmac_sha224_ctx_new(void)
+{
+	return hmac_common_ctx_new(lc_hash_impl_sha224());
+}
+
+static void *
+hmac_sha256_ctx_new(void)
+{
+	return hmac_common_ctx_new(lc_hash_impl_sha256());
+}
+
 static void *
 hmac_sha384_ctx_new(void)
 {
@@ -146,6 +169,26 @@ hmac_ctx_free(void *arg)
 }
 
 
+static struct lc_auth_impl	hmac_sha224_impl = {
+	.init = &hmac_sha224_sha256_init,
+	.update = &hmac_update,
+	.final = &hmac_final,
+	.auth = NULL,
+
+	.ctx_new = &hmac_sha224_ctx_new,
+	.ctx_free = &hmac_ctx_free,
+};
+
+static struct lc_auth_impl	hmac_sha256_impl = {
+	.init = &hmac_sha224_sha256_init,
+	.update = &hmac_update,
+	.final = &hmac_final,
+	.auth = NULL,
+
+	.ctx_new = &hmac_sha256_ctx_new,
+	.ctx_free = &hmac_ctx_free,
+};
+
 static struct lc_auth_impl	hmac_sha384_impl = {
 	.init = &hmac_sha384_sha512_init,
 	.update = &hmac_update,
@@ -166,6 +209,18 @@ static struct lc_auth_impl	hmac_sha512_impl = {
 	.ctx_free = &hmac_ctx_free,
 };
 
+const struct lc_auth_impl *
+lc_auth_impl_hmac_sha224(void)
+{
+	return &hmac_sha224_impl;
+}
+
+const struct lc_auth_impl *
+lc_auth_impl_hmac_sha256(void)
+{
+	return &hmac_sha256_impl;
+}
+
 const struct lc_auth_impl *
 lc_auth_impl_hmac_sha384(void)
 {