summaryrefslogtreecommitdiff
path: root/crypto/hmac-glib.c
blob: a6c1730291bced0a7c7bb5bd3ad7e56460a9e947 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
/*
 * 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,
};