bind9/lib/isc/md5.c
2018-07-19 12:47:03 -04:00

115 lines
3 KiB
C

/*
* Copyright (C) Internet Systems Consortium, Inc. ("ISC")
*
* 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 http://mozilla.org/MPL/2.0/.
*
* See the COPYRIGHT file distributed with this work for additional
* information regarding copyright ownership.
*/
/*! \file
* This code implements the MD5 message-digest algorithm.
* The algorithm is due to Ron Rivest. This code was
* written by Colin Plumb in 1993, no copyright is claimed.
* This code is in the public domain; do with it what you wish.
*
* Equivalent code is available from RSA Data Security, Inc.
* This code has been tested against that, and is equivalent,
* except that you don't need to include two pages of legalese
* with every copy.
*
* To compute the message digest of a chunk of bytes, declare an
* MD5Context structure, pass it to MD5Init, call MD5Update as
* needed on buffers full of bytes, and then call MD5Final, which
* will fill a supplied 16-byte array with the digest.
*/
#include "config.h"
#include <isc/assertions.h>
#include <isc/md5.h>
#include <isc/platform.h>
#include <isc/safe.h>
#include <isc/string.h>
#include <isc/types.h>
#include <isc/util.h>
#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
#define EVP_MD_CTX_new() &(ctx->_ctx)
#define EVP_MD_CTX_free(ptr) EVP_MD_CTX_cleanup(ptr)
#endif
void
isc_md5_init(isc_md5_t *ctx) {
ctx->ctx = EVP_MD_CTX_new();
RUNTIME_CHECK(ctx->ctx != NULL);
if (EVP_DigestInit(ctx->ctx, EVP_md5()) != 1) {
FATAL_ERROR(__FILE__, __LINE__, "Cannot initialize MD5.");
}
}
void
isc_md5_invalidate(isc_md5_t *ctx) {
EVP_MD_CTX_free(ctx->ctx);
ctx->ctx = NULL;
}
void
isc_md5_update(isc_md5_t *ctx, const unsigned char *buf, unsigned int len) {
if (len == 0U)
return;
RUNTIME_CHECK(EVP_DigestUpdate(ctx->ctx,
(const void *) buf,
(size_t) len) == 1);
}
void
isc_md5_final(isc_md5_t *ctx, unsigned char *digest) {
RUNTIME_CHECK(EVP_DigestFinal(ctx->ctx, digest, NULL) == 1);
EVP_MD_CTX_free(ctx->ctx);
ctx->ctx = NULL;
}
/*
* Check for MD5 support; if it does not work, raise a fatal error.
*
* Use "a" as the test vector.
*
* Standard use is testing false and result true.
* Testing use is testing true and result false;
*/
isc_boolean_t
isc_md5_check(isc_boolean_t testing) {
isc_md5_t ctx;
unsigned char input = 'a';
unsigned char digest[ISC_MD5_DIGESTLENGTH];
unsigned char expected[] = {
0x0c, 0xc1, 0x75, 0xb9, 0xc0, 0xf1, 0xb6, 0xa8,
0x31, 0xc3, 0x99, 0xe2, 0x69, 0x77, 0x26, 0x61
};
INSIST(sizeof(expected) == ISC_MD5_DIGESTLENGTH);
/*
* Introduce a fault for testing.
*/
if (testing) {
input ^= 0x01;
}
/*
* These functions do not return anything; any failure will be fatal.
*/
isc_md5_init(&ctx);
isc_md5_update(&ctx, &input, 1U);
isc_md5_final(&ctx, digest);
/*
* Must return true in standard case, should return false for testing.
*/
return (ISC_TF(memcmp(digest, expected, ISC_MD5_DIGESTLENGTH) == 0));
}