qemu/crypto/hmac.c

/*
 * QEMU Crypto hmac algorithms
 *
 * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
 *
 * 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"

static const char hex[] = "0123456789abcdef";

int qcrypto_hmac_bytes(QCryptoHmac *hmac,
                       const char *buf,
                       size_t len,
                       uint8_t **result,
                       size_t *resultlen,
                       Error **errp)
{
    struct iovec iov = {
            .iov_base = (char *)buf,
            .iov_len = len
    };

    return qcrypto_hmac_bytesv(hmac, &iov, 1, result, resultlen, errp);
}

int qcrypto_hmac_digestv(QCryptoHmac *hmac,
                         const struct iovec *iov,
                         size_t niov,
                         char **digest,
                         Error **errp)
{
    uint8_t *result = NULL;
    size_t resultlen = 0;
    size_t i;

    if (qcrypto_hmac_bytesv(hmac, iov, niov, &result, &resultlen, errp) < 0) {
        return -1;
    }

    *digest = g_new0(char, (resultlen * 2) + 1);

    for (i = 0 ; i < resultlen ; i++) {
        (*digest)[(i * 2)] = hex[(result[i] >> 4) & 0xf];
        (*digest)[(i * 2) + 1] = hex[result[i] & 0xf];
    }

    (*digest)[resultlen * 2] = '\0';

    g_free(result);
    return 0;
}

int qcrypto_hmac_digest(QCryptoHmac *hmac,
                        const char *buf,
                        size_t len,
                        char **digest,
                        Error **errp)
{
    struct iovec iov = {
            .iov_base = (char *)buf,
            .iov_len = len
    };

    return qcrypto_hmac_digestv(hmac, &iov, 1, digest, errp);
}