qemu/crypto/hmac-glib.c

166 lines
3.8 KiB
C

/*
* QEMU Crypto hmac algorithms (based on glib)
*
* Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
*
* Authors:
* Longpeng(Mike) <longpeng2@huawei.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or
* (at your option) any later version. See the COPYING file in the
* top-level directory.
*
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "crypto/hmac.h"
#include "hmacpriv.h"
/* Support for HMAC Algos has been added in GLib 2.30 */
#if GLIB_CHECK_VERSION(2, 30, 0)
static int qcrypto_hmac_alg_map[QCRYPTO_HASH_ALG__MAX] = {
[QCRYPTO_HASH_ALG_MD5] = G_CHECKSUM_MD5,
[QCRYPTO_HASH_ALG_SHA1] = G_CHECKSUM_SHA1,
[QCRYPTO_HASH_ALG_SHA256] = G_CHECKSUM_SHA256,
/* Support for HMAC SHA-512 in GLib 2.42 */
#if GLIB_CHECK_VERSION(2, 42, 0)
[QCRYPTO_HASH_ALG_SHA512] = G_CHECKSUM_SHA512,
#else
[QCRYPTO_HASH_ALG_SHA512] = -1,
#endif
[QCRYPTO_HASH_ALG_SHA224] = -1,
[QCRYPTO_HASH_ALG_SHA384] = -1,
[QCRYPTO_HASH_ALG_RIPEMD160] = -1,
};
typedef struct QCryptoHmacGlib QCryptoHmacGlib;
struct QCryptoHmacGlib {
GHmac *ghmac;
};
bool qcrypto_hmac_supports(QCryptoHashAlgorithm alg)
{
if (alg < G_N_ELEMENTS(qcrypto_hmac_alg_map) &&
qcrypto_hmac_alg_map[alg] != -1) {
return true;
}
return false;
}
void *qcrypto_hmac_ctx_new(QCryptoHashAlgorithm alg,
const uint8_t *key, size_t nkey,
Error **errp)
{
QCryptoHmacGlib *ctx;
if (!qcrypto_hmac_supports(alg)) {
error_setg(errp, "Unsupported hmac algorithm %s",
QCryptoHashAlgorithm_str(alg));
return NULL;
}
ctx = g_new0(QCryptoHmacGlib, 1);
ctx->ghmac = g_hmac_new(qcrypto_hmac_alg_map[alg],
(const uint8_t *)key, nkey);
if (!ctx->ghmac) {
error_setg(errp, "Cannot initialize hmac and set key");
goto error;
}
return ctx;
error:
g_free(ctx);
return NULL;
}
static void
qcrypto_glib_hmac_ctx_free(QCryptoHmac *hmac)
{
QCryptoHmacGlib *ctx;
ctx = hmac->opaque;
g_hmac_unref(ctx->ghmac);
g_free(ctx);
}
static int
qcrypto_glib_hmac_bytesv(QCryptoHmac *hmac,
const struct iovec *iov,
size_t niov,
uint8_t **result,
size_t *resultlen,
Error **errp)
{
QCryptoHmacGlib *ctx;
int i, ret;
ctx = hmac->opaque;
for (i = 0; i < niov; i++) {
g_hmac_update(ctx->ghmac, iov[i].iov_base, iov[i].iov_len);
}
ret = g_checksum_type_get_length(qcrypto_hmac_alg_map[hmac->alg]);
if (ret < 0) {
error_setg(errp, "Unable to get hmac length");
return -1;
}
if (*resultlen == 0) {
*resultlen = ret;
*result = g_new0(uint8_t, *resultlen);
} else if (*resultlen != ret) {
error_setg(errp, "Result buffer size %zu is smaller than hmac %d",
*resultlen, ret);
return -1;
}
g_hmac_get_digest(ctx->ghmac, *result, resultlen);
return 0;
}
#else
bool qcrypto_hmac_supports(QCryptoHashAlgorithm alg)
{
return false;
}
void *qcrypto_hmac_ctx_new(QCryptoHashAlgorithm alg,
const uint8_t *key, size_t nkey,
Error **errp)
{
return NULL;
}
static void
qcrypto_glib_hmac_ctx_free(QCryptoHmac *hmac)
{
return;
}
static int
qcrypto_glib_hmac_bytesv(QCryptoHmac *hmac,
const struct iovec *iov,
size_t niov,
uint8_t **result,
size_t *resultlen,
Error **errp)
{
return -1;
}
#endif
QCryptoHmacDriver qcrypto_hmac_lib_driver = {
.hmac_bytesv = qcrypto_glib_hmac_bytesv,
.hmac_free = qcrypto_glib_hmac_ctx_free,
};