cachepc-qemu

Fork of AMDESE/qemu with changes for cachepc side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-qemu
Log | Files | Refs | Submodules | LICENSE | sfeed.txt

hmac-gnutls.c (3550B)

      1/*
      2 * QEMU Crypto hmac algorithms
      3 *
      4 * Copyright (c) 2021 Red Hat, Inc.
      5 *
      6 * Derived from hmac-gcrypt.c:
      7 *
      8 *   Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
      9 *
     10 * This work is licensed under the terms of the GNU GPL, version 2 or
     11 * (at your option) any later version.  See the COPYING file in the
     12 * top-level directory.
     13 *
     14 */
     15
     16#include "qemu/osdep.h"
     17#include <gnutls/crypto.h>
     18
     19#include "qapi/error.h"
     20#include "crypto/hmac.h"
     21#include "hmacpriv.h"
     22
     23static int qcrypto_hmac_alg_map[QCRYPTO_HASH_ALG__MAX] = {
     24    [QCRYPTO_HASH_ALG_MD5] = GNUTLS_MAC_MD5,
     25    [QCRYPTO_HASH_ALG_SHA1] = GNUTLS_MAC_SHA1,
     26    [QCRYPTO_HASH_ALG_SHA224] = GNUTLS_MAC_SHA224,
     27    [QCRYPTO_HASH_ALG_SHA256] = GNUTLS_MAC_SHA256,
     28    [QCRYPTO_HASH_ALG_SHA384] = GNUTLS_MAC_SHA384,
     29    [QCRYPTO_HASH_ALG_SHA512] = GNUTLS_MAC_SHA512,
     30    [QCRYPTO_HASH_ALG_RIPEMD160] = GNUTLS_MAC_RMD160,
     31};
     32
     33typedef struct QCryptoHmacGnutls QCryptoHmacGnutls;
     34struct QCryptoHmacGnutls {
     35    gnutls_hmac_hd_t handle;
     36};
     37
     38bool qcrypto_hmac_supports(QCryptoHashAlgorithm alg)
     39{
     40    size_t i;
     41    const gnutls_digest_algorithm_t *algs;
     42    if (alg >= G_N_ELEMENTS(qcrypto_hmac_alg_map) ||
     43        qcrypto_hmac_alg_map[alg] == GNUTLS_DIG_UNKNOWN) {
     44        return false;
     45    }
     46    algs = gnutls_digest_list();
     47    for (i = 0; algs[i] != GNUTLS_DIG_UNKNOWN; i++) {
     48        if (algs[i] == qcrypto_hmac_alg_map[alg]) {
     49            return true;
     50        }
     51    }
     52    return false;
     53}
     54
     55void *qcrypto_hmac_ctx_new(QCryptoHashAlgorithm alg,
     56                           const uint8_t *key, size_t nkey,
     57                           Error **errp)
     58{
     59    QCryptoHmacGnutls *ctx;
     60    int err;
     61
     62    if (!qcrypto_hmac_supports(alg)) {
     63        error_setg(errp, "Unsupported hmac algorithm %s",
     64                   QCryptoHashAlgorithm_str(alg));
     65        return NULL;
     66    }
     67
     68    ctx = g_new0(QCryptoHmacGnutls, 1);
     69
     70    err = gnutls_hmac_init(&ctx->handle,
     71                           qcrypto_hmac_alg_map[alg],
     72                           (const void *)key, nkey);
     73    if (err != 0) {
     74        error_setg(errp, "Cannot initialize hmac: %s",
     75                   gnutls_strerror(err));
     76        goto error;
     77    }
     78
     79    return ctx;
     80
     81error:
     82    g_free(ctx);
     83    return NULL;
     84}
     85
     86static void
     87qcrypto_gnutls_hmac_ctx_free(QCryptoHmac *hmac)
     88{
     89    QCryptoHmacGnutls *ctx;
     90
     91    ctx = hmac->opaque;
     92    gnutls_hmac_deinit(ctx->handle, NULL);
     93
     94    g_free(ctx);
     95}
     96
     97static int
     98qcrypto_gnutls_hmac_bytesv(QCryptoHmac *hmac,
     99                           const struct iovec *iov,
    100                           size_t niov,
    101                           uint8_t **result,
    102                           size_t *resultlen,
    103                           Error **errp)
    104{
    105    QCryptoHmacGnutls *ctx;
    106    uint32_t ret;
    107    int i;
    108
    109    ctx = hmac->opaque;
    110
    111    for (i = 0; i < niov; i++) {
    112        gnutls_hmac(ctx->handle, iov[i].iov_base, iov[i].iov_len);
    113    }
    114
    115    ret = gnutls_hmac_get_len(qcrypto_hmac_alg_map[hmac->alg]);
    116    if (ret <= 0) {
    117        error_setg(errp, "Unable to get hmac length: %s",
    118                   gnutls_strerror(ret));
    119        return -1;
    120    }
    121
    122    if (*resultlen == 0) {
    123        *resultlen = ret;
    124        *result = g_new0(uint8_t, *resultlen);
    125    } else if (*resultlen != ret) {
    126        error_setg(errp, "Result buffer size %zu is smaller than hmac %d",
    127                   *resultlen, ret);
    128        return -1;
    129    }
    130
    131    gnutls_hmac_output(ctx->handle, *result);
    132
    133    return 0;
    134}
    135
    136QCryptoHmacDriver qcrypto_hmac_lib_driver = {
    137    .hmac_bytesv = qcrypto_gnutls_hmac_bytesv,
    138    .hmac_free = qcrypto_gnutls_hmac_ctx_free,
    139};