xref: /openbmc/qemu/crypto/hmac-nettle.c (revision a1ab6788)
1 /*
2  * QEMU Crypto hmac algorithms (based on nettle)
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 #include <nettle/hmac.h>
20 
21 typedef void (*qcrypto_nettle_hmac_setkey)(void *ctx,
22                                            size_t key_length,
23                                            const uint8_t *key);
24 
25 typedef void (*qcrypto_nettle_hmac_update)(void *ctx,
26                                            size_t length,
27                                            const uint8_t *data);
28 
29 typedef void (*qcrypto_nettle_hmac_digest)(void *ctx,
30                                            size_t length,
31                                            uint8_t *digest);
32 
33 typedef struct QCryptoHmacNettle QCryptoHmacNettle;
34 struct QCryptoHmacNettle {
35     union qcrypto_nettle_hmac_ctx {
36         struct hmac_md5_ctx md5_ctx;
37         struct hmac_sha1_ctx sha1_ctx;
38         struct hmac_sha256_ctx sha256_ctx; /* equals hmac_sha224_ctx */
39         struct hmac_sha512_ctx sha512_ctx; /* equals hmac_sha384_ctx */
40         struct hmac_ripemd160_ctx ripemd160_ctx;
41     } u;
42 };
43 
44 struct qcrypto_nettle_hmac_alg {
45     qcrypto_nettle_hmac_setkey setkey;
46     qcrypto_nettle_hmac_update update;
47     qcrypto_nettle_hmac_digest digest;
48     size_t len;
49 } qcrypto_hmac_alg_map[QCRYPTO_HASH_ALGO__MAX] = {
50     [QCRYPTO_HASH_ALGO_MD5] = {
51         .setkey = (qcrypto_nettle_hmac_setkey)hmac_md5_set_key,
52         .update = (qcrypto_nettle_hmac_update)hmac_md5_update,
53         .digest = (qcrypto_nettle_hmac_digest)hmac_md5_digest,
54         .len = MD5_DIGEST_SIZE,
55     },
56     [QCRYPTO_HASH_ALGO_SHA1] = {
57         .setkey = (qcrypto_nettle_hmac_setkey)hmac_sha1_set_key,
58         .update = (qcrypto_nettle_hmac_update)hmac_sha1_update,
59         .digest = (qcrypto_nettle_hmac_digest)hmac_sha1_digest,
60         .len = SHA1_DIGEST_SIZE,
61     },
62     [QCRYPTO_HASH_ALGO_SHA224] = {
63         .setkey = (qcrypto_nettle_hmac_setkey)hmac_sha224_set_key,
64         .update = (qcrypto_nettle_hmac_update)hmac_sha224_update,
65         .digest = (qcrypto_nettle_hmac_digest)hmac_sha224_digest,
66         .len = SHA224_DIGEST_SIZE,
67     },
68     [QCRYPTO_HASH_ALGO_SHA256] = {
69         .setkey = (qcrypto_nettle_hmac_setkey)hmac_sha256_set_key,
70         .update = (qcrypto_nettle_hmac_update)hmac_sha256_update,
71         .digest = (qcrypto_nettle_hmac_digest)hmac_sha256_digest,
72         .len = SHA256_DIGEST_SIZE,
73     },
74     [QCRYPTO_HASH_ALGO_SHA384] = {
75         .setkey = (qcrypto_nettle_hmac_setkey)hmac_sha384_set_key,
76         .update = (qcrypto_nettle_hmac_update)hmac_sha384_update,
77         .digest = (qcrypto_nettle_hmac_digest)hmac_sha384_digest,
78         .len = SHA384_DIGEST_SIZE,
79     },
80     [QCRYPTO_HASH_ALGO_SHA512] = {
81         .setkey = (qcrypto_nettle_hmac_setkey)hmac_sha512_set_key,
82         .update = (qcrypto_nettle_hmac_update)hmac_sha512_update,
83         .digest = (qcrypto_nettle_hmac_digest)hmac_sha512_digest,
84         .len = SHA512_DIGEST_SIZE,
85     },
86     [QCRYPTO_HASH_ALGO_RIPEMD160] = {
87         .setkey = (qcrypto_nettle_hmac_setkey)hmac_ripemd160_set_key,
88         .update = (qcrypto_nettle_hmac_update)hmac_ripemd160_update,
89         .digest = (qcrypto_nettle_hmac_digest)hmac_ripemd160_digest,
90         .len = RIPEMD160_DIGEST_SIZE,
91     },
92 };
93 
94 bool qcrypto_hmac_supports(QCryptoHashAlgo alg)
95 {
96     if (alg < G_N_ELEMENTS(qcrypto_hmac_alg_map) &&
97         qcrypto_hmac_alg_map[alg].setkey != NULL) {
98         return true;
99     }
100 
101     return false;
102 }
103 
104 void *qcrypto_hmac_ctx_new(QCryptoHashAlgo alg,
105                            const uint8_t *key, size_t nkey,
106                            Error **errp)
107 {
108     QCryptoHmacNettle *ctx;
109 
110     if (!qcrypto_hmac_supports(alg)) {
111         error_setg(errp, "Unsupported hmac algorithm %s",
112                    QCryptoHashAlgo_str(alg));
113         return NULL;
114     }
115 
116     ctx = g_new0(QCryptoHmacNettle, 1);
117 
118     qcrypto_hmac_alg_map[alg].setkey(&ctx->u, nkey, key);
119 
120     return ctx;
121 }
122 
123 static void
124 qcrypto_nettle_hmac_ctx_free(QCryptoHmac *hmac)
125 {
126     QCryptoHmacNettle *ctx;
127 
128     ctx = hmac->opaque;
129     g_free(ctx);
130 }
131 
132 static int
133 qcrypto_nettle_hmac_bytesv(QCryptoHmac *hmac,
134                            const struct iovec *iov,
135                            size_t niov,
136                            uint8_t **result,
137                            size_t *resultlen,
138                            Error **errp)
139 {
140     QCryptoHmacNettle *ctx;
141     size_t i;
142 
143     ctx = (QCryptoHmacNettle *)hmac->opaque;
144 
145     for (i = 0; i < niov; ++i) {
146         size_t len = iov[i].iov_len;
147         uint8_t *base = iov[i].iov_base;
148         while (len) {
149             size_t shortlen = MIN(len, UINT_MAX);
150             qcrypto_hmac_alg_map[hmac->alg].update(&ctx->u, len, base);
151             len -= shortlen;
152             base += len;
153         }
154     }
155 
156     if (*resultlen == 0) {
157         *resultlen = qcrypto_hmac_alg_map[hmac->alg].len;
158         *result = g_new0(uint8_t, *resultlen);
159     } else if (*resultlen != qcrypto_hmac_alg_map[hmac->alg].len) {
160         error_setg(errp,
161                    "Result buffer size %zu is smaller than hash %zu",
162                    *resultlen, qcrypto_hmac_alg_map[hmac->alg].len);
163         return -1;
164     }
165 
166     qcrypto_hmac_alg_map[hmac->alg].digest(&ctx->u, *resultlen, *result);
167 
168     return 0;
169 }
170 
171 QCryptoHmacDriver qcrypto_hmac_lib_driver = {
172     .hmac_bytesv = qcrypto_nettle_hmac_bytesv,
173     .hmac_free = qcrypto_nettle_hmac_ctx_free,
174 };
175