LXR qemu/crypto/hmac-glib.c

   1/*
   2 * QEMU Crypto hmac algorithms (based on glib)
   3 *
   4 * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
   5 *
   6 * Authors:
   7 *    Longpeng(Mike) <longpeng2@huawei.com>
   8 *
   9 * This work is licensed under the terms of the GNU GPL, version 2 or
  10 * (at your option) any later version.  See the COPYING file in the
  11 * top-level directory.
  12 *
  13 */
  14
  15#include "qemu/osdep.h"
  16#include "qapi/error.h"
  17#include "crypto/hmac.h"
  18#include "hmacpriv.h"
  19
  20static int qcrypto_hmac_alg_map[QCRYPTO_HASH_ALG__MAX] = {
  21    [QCRYPTO_HASH_ALG_MD5] = G_CHECKSUM_MD5,
  22    [QCRYPTO_HASH_ALG_SHA1] = G_CHECKSUM_SHA1,
  23    [QCRYPTO_HASH_ALG_SHA256] = G_CHECKSUM_SHA256,
  24    [QCRYPTO_HASH_ALG_SHA512] = G_CHECKSUM_SHA512,
  25    [QCRYPTO_HASH_ALG_SHA224] = -1,
  26    [QCRYPTO_HASH_ALG_SHA384] = -1,
  27    [QCRYPTO_HASH_ALG_RIPEMD160] = -1,
  28};
  29
  30typedef struct QCryptoHmacGlib QCryptoHmacGlib;
  31struct QCryptoHmacGlib {
  32    GHmac *ghmac;
  33};
  34
  35bool qcrypto_hmac_supports(QCryptoHashAlgorithm alg)
  36{
  37    if (alg < G_N_ELEMENTS(qcrypto_hmac_alg_map) &&
  38        qcrypto_hmac_alg_map[alg] != -1) {
  39        return true;
  40    }
  41
  42    return false;
  43}
  44
  45void *qcrypto_hmac_ctx_new(QCryptoHashAlgorithm alg,
  46                           const uint8_t *key, size_t nkey,
  47                           Error **errp)
  48{
  49    QCryptoHmacGlib *ctx;
  50
  51    if (!qcrypto_hmac_supports(alg)) {
  52        error_setg(errp, "Unsupported hmac algorithm %s",
  53                   QCryptoHashAlgorithm_str(alg));
  54        return NULL;
  55    }
  56
  57    ctx = g_new0(QCryptoHmacGlib, 1);
  58
  59    ctx->ghmac = g_hmac_new(qcrypto_hmac_alg_map[alg],
  60                            (const uint8_t *)key, nkey);
  61    if (!ctx->ghmac) {
  62        error_setg(errp, "Cannot initialize hmac and set key");
  63        goto error;
  64    }
  65
  66    return ctx;
  67
  68error:
  69    g_free(ctx);
  70    return NULL;
  71}
  72
  73static void
  74qcrypto_glib_hmac_ctx_free(QCryptoHmac *hmac)
  75{
  76    QCryptoHmacGlib *ctx;
  77
  78    ctx = hmac->opaque;
  79    g_hmac_unref(ctx->ghmac);
  80
  81    g_free(ctx);
  82}
  83
  84static int
  85qcrypto_glib_hmac_bytesv(QCryptoHmac *hmac,
  86                         const struct iovec *iov,
  87                         size_t niov,
  88                         uint8_t **result,
  89                         size_t *resultlen,
  90                         Error **errp)
  91{
  92    QCryptoHmacGlib *ctx;
  93    int i, ret;
  94
  95    ctx = hmac->opaque;
  96
  97    for (i = 0; i < niov; i++) {
  98        g_hmac_update(ctx->ghmac, iov[i].iov_base, iov[i].iov_len);
  99    }
 100
 101    ret = g_checksum_type_get_length(qcrypto_hmac_alg_map[hmac->alg]);
 102    if (ret < 0) {
 103        error_setg(errp, "Unable to get hmac length");
 104        return -1;
 105    }
 106
 107    if (*resultlen == 0) {
 108        *resultlen = ret;
 109        *result = g_new0(uint8_t, *resultlen);
 110    } else if (*resultlen != ret) {
 111        error_setg(errp, "Result buffer size %zu is smaller than hmac %d",
 112                   *resultlen, ret);
 113        return -1;
 114    }
 115
 116    g_hmac_get_digest(ctx->ghmac, *result, resultlen);
 117
 118    return 0;
 119}
 120
 121QCryptoHmacDriver qcrypto_hmac_lib_driver = {
 122    .hmac_bytesv = qcrypto_glib_hmac_bytesv,
 123    .hmac_free = qcrypto_glib_hmac_ctx_free,
 124};
 125