xref: /openbmc/qemu/crypto/hmac-nettle.c (revision c00506aa)
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 #if CONFIG_NETTLE_VERSION_MAJOR < 3
22 typedef unsigned int hmac_length_t;
23 #else
24 typedef size_t hmac_length_t;
25 #endif
26 
27 typedef void (*qcrypto_nettle_hmac_setkey)(void *ctx,
28                                            hmac_length_t key_length,
29                                            const uint8_t *key);
30 
31 typedef void (*qcrypto_nettle_hmac_update)(void *ctx,
32                                            hmac_length_t length,
33                                            const uint8_t *data);
34 
35 typedef void (*qcrypto_nettle_hmac_digest)(void *ctx,
36                                            hmac_length_t length,
37                                            uint8_t *digest);
38 
39 typedef struct QCryptoHmacNettle QCryptoHmacNettle;
40 struct QCryptoHmacNettle {
41     union qcrypto_nettle_hmac_ctx {
42         struct hmac_md5_ctx md5_ctx;
43         struct hmac_sha1_ctx sha1_ctx;
44         struct hmac_sha256_ctx sha256_ctx; /* equals hmac_sha224_ctx */
45         struct hmac_sha512_ctx sha512_ctx; /* equals hmac_sha384_ctx */
46         struct hmac_ripemd160_ctx ripemd160_ctx;
47     } u;
48 };
49 
50 struct qcrypto_nettle_hmac_alg {
51     qcrypto_nettle_hmac_setkey setkey;
52     qcrypto_nettle_hmac_update update;
53     qcrypto_nettle_hmac_digest digest;
54     size_t len;
55 } qcrypto_hmac_alg_map[QCRYPTO_HASH_ALG__MAX] = {
56     [QCRYPTO_HASH_ALG_MD5] = {
57         .setkey = (qcrypto_nettle_hmac_setkey)hmac_md5_set_key,
58         .update = (qcrypto_nettle_hmac_update)hmac_md5_update,
59         .digest = (qcrypto_nettle_hmac_digest)hmac_md5_digest,
60         .len = MD5_DIGEST_SIZE,
61     },
62     [QCRYPTO_HASH_ALG_SHA1] = {
63         .setkey = (qcrypto_nettle_hmac_setkey)hmac_sha1_set_key,
64         .update = (qcrypto_nettle_hmac_update)hmac_sha1_update,
65         .digest = (qcrypto_nettle_hmac_digest)hmac_sha1_digest,
66         .len = SHA1_DIGEST_SIZE,
67     },
68     [QCRYPTO_HASH_ALG_SHA224] = {
69         .setkey = (qcrypto_nettle_hmac_setkey)hmac_sha224_set_key,
70         .update = (qcrypto_nettle_hmac_update)hmac_sha224_update,
71         .digest = (qcrypto_nettle_hmac_digest)hmac_sha224_digest,
72         .len = SHA224_DIGEST_SIZE,
73     },
74     [QCRYPTO_HASH_ALG_SHA256] = {
75         .setkey = (qcrypto_nettle_hmac_setkey)hmac_sha256_set_key,
76         .update = (qcrypto_nettle_hmac_update)hmac_sha256_update,
77         .digest = (qcrypto_nettle_hmac_digest)hmac_sha256_digest,
78         .len = SHA256_DIGEST_SIZE,
79     },
80     [QCRYPTO_HASH_ALG_SHA384] = {
81         .setkey = (qcrypto_nettle_hmac_setkey)hmac_sha384_set_key,
82         .update = (qcrypto_nettle_hmac_update)hmac_sha384_update,
83         .digest = (qcrypto_nettle_hmac_digest)hmac_sha384_digest,
84         .len = SHA384_DIGEST_SIZE,
85     },
86     [QCRYPTO_HASH_ALG_SHA512] = {
87         .setkey = (qcrypto_nettle_hmac_setkey)hmac_sha512_set_key,
88         .update = (qcrypto_nettle_hmac_update)hmac_sha512_update,
89         .digest = (qcrypto_nettle_hmac_digest)hmac_sha512_digest,
90         .len = SHA512_DIGEST_SIZE,
91     },
92     [QCRYPTO_HASH_ALG_RIPEMD160] = {
93         .setkey = (qcrypto_nettle_hmac_setkey)hmac_ripemd160_set_key,
94         .update = (qcrypto_nettle_hmac_update)hmac_ripemd160_update,
95         .digest = (qcrypto_nettle_hmac_digest)hmac_ripemd160_digest,
96         .len = RIPEMD160_DIGEST_SIZE,
97     },
98 };
99 
100 bool qcrypto_hmac_supports(QCryptoHashAlgorithm alg)
101 {
102     if (alg < G_N_ELEMENTS(qcrypto_hmac_alg_map) &&
103         qcrypto_hmac_alg_map[alg].setkey != NULL) {
104         return true;
105     }
106 
107     return false;
108 }
109 
110 void *qcrypto_hmac_ctx_new(QCryptoHashAlgorithm alg,
111                            const uint8_t *key, size_t nkey,
112                            Error **errp)
113 {
114     QCryptoHmacNettle *ctx;
115 
116     if (!qcrypto_hmac_supports(alg)) {
117         error_setg(errp, "Unsupported hmac algorithm %s",
118                    QCryptoHashAlgorithm_str(alg));
119         return NULL;
120     }
121 
122     ctx = g_new0(QCryptoHmacNettle, 1);
123 
124     qcrypto_hmac_alg_map[alg].setkey(&ctx->u, nkey, key);
125 
126     return ctx;
127 }
128 
129 static void
130 qcrypto_nettle_hmac_ctx_free(QCryptoHmac *hmac)
131 {
132     QCryptoHmacNettle *ctx;
133 
134     ctx = hmac->opaque;
135     g_free(ctx);
136 }
137 
138 static int
139 qcrypto_nettle_hmac_bytesv(QCryptoHmac *hmac,
140                            const struct iovec *iov,
141                            size_t niov,
142                            uint8_t **result,
143                            size_t *resultlen,
144                            Error **errp)
145 {
146     QCryptoHmacNettle *ctx;
147     size_t i;
148 
149     ctx = (QCryptoHmacNettle *)hmac->opaque;
150 
151     for (i = 0; i < niov; ++i) {
152         size_t len = iov[i].iov_len;
153         uint8_t *base = iov[i].iov_base;
154         while (len) {
155             size_t shortlen = MIN(len, UINT_MAX);
156             qcrypto_hmac_alg_map[hmac->alg].update(&ctx->u, len, base);
157             len -= shortlen;
158             base += len;
159         }
160     }
161 
162     if (*resultlen == 0) {
163         *resultlen = qcrypto_hmac_alg_map[hmac->alg].len;
164         *result = g_new0(uint8_t, *resultlen);
165     } else if (*resultlen != qcrypto_hmac_alg_map[hmac->alg].len) {
166         error_setg(errp,
167                    "Result buffer size %zu is smaller than hash %zu",
168                    *resultlen, qcrypto_hmac_alg_map[hmac->alg].len);
169         return -1;
170     }
171 
172     qcrypto_hmac_alg_map[hmac->alg].digest(&ctx->u, *resultlen, *result);
173 
174     return 0;
175 }
176 
177 QCryptoHmacDriver qcrypto_hmac_lib_driver = {
178     .hmac_bytesv = qcrypto_nettle_hmac_bytesv,
179     .hmac_free = qcrypto_nettle_hmac_ctx_free,
180 };
181