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
  20/* Support for HMAC Algos has been added in GLib 2.30 */
  21#if GLIB_CHECK_VERSION(2, 30, 0)
  22
  23static int qcrypto_hmac_alg_map[QCRYPTO_HASH_ALG__MAX] = {
  24    [QCRYPTO_HASH_ALG_MD5] = G_CHECKSUM_MD5,
  25    [QCRYPTO_HASH_ALG_SHA1] = G_CHECKSUM_SHA1,
  26    [QCRYPTO_HASH_ALG_SHA256] = G_CHECKSUM_SHA256,
  27/* Support for HMAC SHA-512 in GLib 2.42 */
  28#if GLIB_CHECK_VERSION(2, 42, 0)
  29    [QCRYPTO_HASH_ALG_SHA512] = G_CHECKSUM_SHA512,
  30#else
  31    [QCRYPTO_HASH_ALG_SHA512] = -1,
  32#endif
  33    [QCRYPTO_HASH_ALG_SHA224] = -1,
  34    [QCRYPTO_HASH_ALG_SHA384] = -1,
  35    [QCRYPTO_HASH_ALG_RIPEMD160] = -1,
  36};
  37
  38typedef struct QCryptoHmacGlib QCryptoHmacGlib;
  39struct QCryptoHmacGlib {
  40    GHmac *ghmac;
  41};
  42
  43bool qcrypto_hmac_supports(QCryptoHashAlgorithm alg)
  44{
  45    if (alg < G_N_ELEMENTS(qcrypto_hmac_alg_map) &&
  46        qcrypto_hmac_alg_map[alg] != -1) {
  47        return true;
  48    }
  49
  50    return false;
  51}
  52
  53void *qcrypto_hmac_ctx_new(QCryptoHashAlgorithm alg,
  54                           const uint8_t *key, size_t nkey,
  55                           Error **errp)
  56{
  57    QCryptoHmacGlib *ctx;
  58
  59    if (!qcrypto_hmac_supports(alg)) {
  60        error_setg(errp, "Unsupported hmac algorithm %s",
  61                   QCryptoHashAlgorithm_str(alg));
  62        return NULL;
  63    }
  64
  65    ctx = g_new0(QCryptoHmacGlib, 1);
  66
  67    ctx->ghmac = g_hmac_new(qcrypto_hmac_alg_map[alg],
  68                            (const uint8_t *)key, nkey);
  69    if (!ctx->ghmac) {
  70        error_setg(errp, "Cannot initialize hmac and set key");
  71        goto error;
  72    }
  73
  74    return ctx;
  75
  76error:
  77    g_free(ctx);
  78    return NULL;
  79}
  80
  81static void
  82qcrypto_glib_hmac_ctx_free(QCryptoHmac *hmac)
  83{
  84    QCryptoHmacGlib *ctx;
  85
  86    ctx = hmac->opaque;
  87    g_hmac_unref(ctx->ghmac);
  88
  89    g_free(ctx);
  90}
  91
  92static int
  93qcrypto_glib_hmac_bytesv(QCryptoHmac *hmac,
  94                         const struct iovec *iov,
  95                         size_t niov,
  96                         uint8_t **result,
  97                         size_t *resultlen,
  98                         Error **errp)
  99{
 100    QCryptoHmacGlib *ctx;
 101    int i, ret;
 102
 103    ctx = hmac->opaque;
 104
 105    for (i = 0; i < niov; i++) {
 106        g_hmac_update(ctx->ghmac, iov[i].iov_base, iov[i].iov_len);
 107    }
 108
 109    ret = g_checksum_type_get_length(qcrypto_hmac_alg_map[hmac->alg]);
 110    if (ret < 0) {
 111        error_setg(errp, "Unable to get hmac length");
 112        return -1;
 113    }
 114
 115    if (*resultlen == 0) {
 116        *resultlen = ret;
 117        *result = g_new0(uint8_t, *resultlen);
 118    } else if (*resultlen != ret) {
 119        error_setg(errp, "Result buffer size %zu is smaller than hmac %d",
 120                   *resultlen, ret);
 121        return -1;
 122    }
 123
 124    g_hmac_get_digest(ctx->ghmac, *result, resultlen);
 125
 126    return 0;
 127}
 128
 129#else
 130
 131bool qcrypto_hmac_supports(QCryptoHashAlgorithm alg)
 132{
 133    return false;
 134}
 135
 136void *qcrypto_hmac_ctx_new(QCryptoHashAlgorithm alg,
 137                           const uint8_t *key, size_t nkey,
 138                           Error **errp)
 139{
 140    return NULL;
 141}
 142
 143static void
 144qcrypto_glib_hmac_ctx_free(QCryptoHmac *hmac)
 145{
 146    return;
 147}
 148
 149static int
 150qcrypto_glib_hmac_bytesv(QCryptoHmac *hmac,
 151                         const struct iovec *iov,
 152                         size_t niov,
 153                         uint8_t **result,
 154                         size_t *resultlen,
 155                         Error **errp)
 156{
 157    return -1;
 158}
 159
 160#endif
 161
 162QCryptoHmacDriver qcrypto_hmac_lib_driver = {
 163    .hmac_bytesv = qcrypto_glib_hmac_bytesv,
 164    .hmac_free = qcrypto_glib_hmac_ctx_free,
 165};
 166