1 files changed, 175 insertions, 0 deletions
diff --git a/lib/isc/md.c b/lib/isc/md.c
new file mode 100644
index 0000000..0c6a70d
--- /dev/null
+++ b/lib/isc/md.c
@@ -0,0 +1,175 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, you can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+#include <stdio.h>
+
+#include <openssl/err.h>
+#include <openssl/evp.h>
+#include <openssl/opensslv.h>
+
+#include <isc/md.h>
+#include <isc/util.h>
+
+#include "openssl_shim.h"
+
+isc_md_t *
+isc_md_new(void) {
+	isc_md_t *md = EVP_MD_CTX_new();
+	RUNTIME_CHECK(md != NULL);
+	return (md);
+}
+
+void
+isc_md_free(isc_md_t *md) {
+	if (ISC_UNLIKELY(md == NULL)) {
+		return;
+	}
+
+	EVP_MD_CTX_free(md);
+}
+
+isc_result_t
+isc_md_init(isc_md_t *md, const isc_md_type_t *md_type) {
+	REQUIRE(md != NULL);
+
+	if (md_type == NULL) {
+		return (ISC_R_NOTIMPLEMENTED);
+	}
+
+	if (EVP_DigestInit_ex(md, md_type, NULL) != 1) {
+		return (ISC_R_CRYPTOFAILURE);
+	}
+
+	return (ISC_R_SUCCESS);
+}
+
+isc_result_t
+isc_md_reset(isc_md_t *md) {
+	REQUIRE(md != NULL);
+
+	if (EVP_MD_CTX_reset(md) != 1) {
+		return (ISC_R_CRYPTOFAILURE);
+	}
+
+	return (ISC_R_SUCCESS);
+}
+
+isc_result_t
+isc_md_update(isc_md_t *md, const unsigned char *buf, const size_t len) {
+	REQUIRE(md != NULL);
+
+	if (ISC_UNLIKELY(buf == NULL || len == 0)) {
+		return (ISC_R_SUCCESS);
+	}
+
+	if (EVP_DigestUpdate(md, buf, len) != 1) {
+		return (ISC_R_CRYPTOFAILURE);
+	}
+
+	return (ISC_R_SUCCESS);
+}
+
+isc_result_t
+isc_md_final(isc_md_t *md, unsigned char *digest, unsigned int *digestlen) {
+	REQUIRE(md != NULL);
+	REQUIRE(digest != NULL);
+
+	if (EVP_DigestFinal_ex(md, digest, digestlen) != 1) {
+		return (ISC_R_CRYPTOFAILURE);
+	}
+
+	return (ISC_R_SUCCESS);
+}
+
+const isc_md_type_t *
+isc_md_get_md_type(isc_md_t *md) {
+	REQUIRE(md != NULL);
+
+	return (EVP_MD_CTX_md(md));
+}
+
+size_t
+isc_md_get_size(isc_md_t *md) {
+	REQUIRE(md != NULL);
+
+	return (EVP_MD_CTX_size(md));
+}
+
+size_t
+isc_md_get_block_size(isc_md_t *md) {
+	REQUIRE(md != NULL);
+
+	return (EVP_MD_CTX_block_size(md));
+}
+
+size_t
+isc_md_type_get_size(const isc_md_type_t *md_type) {
+	STATIC_ASSERT(ISC_MAX_MD_SIZE >= EVP_MAX_MD_SIZE,
+		      "Change ISC_MAX_MD_SIZE to be greater than or equal to "
+		      "EVP_MAX_MD_SIZE");
+	if (md_type != NULL) {
+		return ((size_t)EVP_MD_size(md_type));
+	}
+
+	return (ISC_MAX_MD_SIZE);
+}
+
+size_t
+isc_md_type_get_block_size(const isc_md_type_t *md_type) {
+	STATIC_ASSERT(ISC_MAX_MD_SIZE >= EVP_MAX_MD_SIZE,
+		      "Change ISC_MAX_MD_SIZE to be greater than or equal to "
+		      "EVP_MAX_MD_SIZE");
+	if (md_type != NULL) {
+		return ((size_t)EVP_MD_block_size(md_type));
+	}
+
+	return (ISC_MAX_MD_SIZE);
+}
+
+isc_result_t
+isc_md(const isc_md_type_t *md_type, const unsigned char *buf, const size_t len,
+       unsigned char *digest, unsigned int *digestlen) {
+	isc_md_t *md;
+	isc_result_t res;
+
+	md = isc_md_new();
+
+	res = isc_md_init(md, md_type);
+	if (res != ISC_R_SUCCESS) {
+		goto end;
+	}
+
+	res = isc_md_update(md, buf, len);
+	if (res != ISC_R_SUCCESS) {
+		goto end;
+	}
+
+	res = isc_md_final(md, digest, digestlen);
+	if (res != ISC_R_SUCCESS) {
+		goto end;
+	}
+end:
+	isc_md_free(md);
+
+	return (res);
+}
+
+#define md_register_algorithm(alg) \
+	const isc_md_type_t *isc__md_##alg(void) { return (EVP_##alg()); }
+
+md_register_algorithm(md5);
+md_register_algorithm(sha1);
+md_register_algorithm(sha224);
+md_register_algorithm(sha256);
+md_register_algorithm(sha384);
+md_register_algorithm(sha512);