libvirt/src/util/vircrypto.c

79 lines
2.1 KiB
C
Raw Normal View History

/*
* vircrypto.c: cryptographic helper APIs
*
* Copyright (C) 2014 Red Hat, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see
* <http://www.gnu.org/licenses/>.
*/
#include <config.h>
#include "vircrypto.h"
#include "virerror.h"
#include "viralloc.h"
#include "md5.h"
#include "sha256.h"
#define VIR_FROM_THIS VIR_FROM_CRYPTO
static const char hex[] = "0123456789abcdef";
struct virHashInfo {
void *(*func)(const char *buf, size_t len, void *res);
size_t hashlen;
} hashinfo[] = {
{ md5_buffer, MD5_DIGEST_SIZE },
{ sha256_buffer, SHA256_DIGEST_SIZE },
};
#define VIR_CRYPTO_LARGEST_DIGEST_SIZE SHA256_DIGEST_SIZE
verify(ARRAY_CARDINALITY(hashinfo) == VIR_CRYPTO_HASH_LAST);
int
virCryptoHashString(virCryptoHash hash,
const char *input,
char **output)
{
unsigned char buf[VIR_CRYPTO_LARGEST_DIGEST_SIZE];
size_t hashstrlen;
size_t i;
if (hash >= VIR_CRYPTO_HASH_LAST) {
virReportError(VIR_ERR_INVALID_ARG,
_("Unknown crypto hash %d"), hash);
return -1;
}
hashstrlen = (hashinfo[hash].hashlen * 2) + 1;
if (!(hashinfo[hash].func(input, strlen(input), buf))) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("Unable to compute hash of data"));
return -1;
}
if (VIR_ALLOC_N(*output, hashstrlen) < 0)
return -1;
for (i = 0; i < hashinfo[hash].hashlen; i++) {
(*output)[i * 2] = hex[(buf[i] >> 4) & 0xf];
(*output)[(i * 2) + 1] = hex[buf[i] & 0xf];
}
return 0;
}