xref: /openbmc/qemu/crypto/hash-afalg.c (revision 2e1cacfb)
1 /*
2  * QEMU Crypto af_alg-backend hash/hmac support
3  *
4  * Copyright (c) 2024 Seagate Technology LLC and/or its Affiliates
5  * Copyright (c) 2017 HUAWEI TECHNOLOGIES CO., LTD.
6  *
7  * Authors:
8  *    Longpeng(Mike) <longpeng2@huawei.com>
9  *
10  * This work is licensed under the terms of the GNU GPL, version 2 or
11  * (at your option) any later version.  See the COPYING file in the
12  * top-level directory.
13  */
14 #include "qemu/osdep.h"
15 #include "qemu/iov.h"
16 #include "qemu/sockets.h"
17 #include "qapi/error.h"
18 #include "crypto/hash.h"
19 #include "crypto/hmac.h"
20 #include "hashpriv.h"
21 #include "hmacpriv.h"
22 
23 static char *
24 qcrypto_afalg_hash_format_name(QCryptoHashAlgo alg,
25                                bool is_hmac,
26                                Error **errp)
27 {
28     char *name;
29     const char *alg_name;
30 
31     switch (alg) {
32     case QCRYPTO_HASH_ALGO_MD5:
33         alg_name = "md5";
34         break;
35     case QCRYPTO_HASH_ALGO_SHA1:
36         alg_name = "sha1";
37         break;
38     case QCRYPTO_HASH_ALGO_SHA224:
39         alg_name = "sha224";
40         break;
41     case QCRYPTO_HASH_ALGO_SHA256:
42         alg_name = "sha256";
43         break;
44     case QCRYPTO_HASH_ALGO_SHA384:
45         alg_name = "sha384";
46         break;
47     case QCRYPTO_HASH_ALGO_SHA512:
48         alg_name = "sha512";
49         break;
50     case QCRYPTO_HASH_ALGO_RIPEMD160:
51         alg_name = "rmd160";
52         break;
53 
54     default:
55         error_setg(errp, "Unsupported hash algorithm %d", alg);
56         return NULL;
57     }
58 
59     if (is_hmac) {
60         name = g_strdup_printf("hmac(%s)", alg_name);
61     } else {
62         name = g_strdup_printf("%s", alg_name);
63     }
64 
65     return name;
66 }
67 
68 static QCryptoAFAlgo *
69 qcrypto_afalg_hash_hmac_ctx_new(QCryptoHashAlgo alg,
70                                 const uint8_t *key, size_t nkey,
71                                 bool is_hmac, Error **errp)
72 {
73     QCryptoAFAlgo *afalg;
74     char *name;
75 
76     name = qcrypto_afalg_hash_format_name(alg, is_hmac, errp);
77     if (!name) {
78         return NULL;
79     }
80 
81     afalg = qcrypto_afalg_comm_alloc(AFALG_TYPE_HASH, name, errp);
82     if (!afalg) {
83         g_free(name);
84         return NULL;
85     }
86 
87     g_free(name);
88 
89     /* HMAC needs setkey */
90     if (is_hmac) {
91         if (setsockopt(afalg->tfmfd, SOL_ALG, ALG_SET_KEY,
92                        key, nkey) != 0) {
93             error_setg_errno(errp, errno, "Set hmac key failed");
94             qcrypto_afalg_comm_free(afalg);
95             return NULL;
96         }
97     }
98 
99     return afalg;
100 }
101 
102 static QCryptoAFAlgo *
103 qcrypto_afalg_hash_ctx_new(QCryptoHashAlgo alg,
104                            Error **errp)
105 {
106     return qcrypto_afalg_hash_hmac_ctx_new(alg, NULL, 0, false, errp);
107 }
108 
109 QCryptoAFAlgo *
110 qcrypto_afalg_hmac_ctx_new(QCryptoHashAlgo alg,
111                            const uint8_t *key, size_t nkey,
112                            Error **errp)
113 {
114     return qcrypto_afalg_hash_hmac_ctx_new(alg, key, nkey, true, errp);
115 }
116 
117 static
118 QCryptoHash *qcrypto_afalg_hash_new(QCryptoHashAlgo alg, Error **errp)
119 {
120     /* Check if hash algorithm is supported */
121     char *alg_name = qcrypto_afalg_hash_format_name(alg, false, NULL);
122     QCryptoHash *hash;
123 
124     if (alg_name == NULL) {
125         error_setg(errp, "Unknown hash algorithm %d", alg);
126         return NULL;
127     }
128 
129     g_free(alg_name);
130 
131     hash = g_new(QCryptoHash, 1);
132     hash->alg = alg;
133     hash->opaque = qcrypto_afalg_hash_ctx_new(alg, errp);
134     if (!hash->opaque) {
135         free(hash);
136         return NULL;
137     }
138 
139     return hash;
140 }
141 
142 static
143 void qcrypto_afalg_hash_free(QCryptoHash *hash)
144 {
145     QCryptoAFAlg *ctx = hash->opaque;
146 
147     if (ctx) {
148         qcrypto_afalg_comm_free(ctx);
149     }
150 
151     g_free(hash);
152 }
153 
154 /**
155  * Send data to the kernel's crypto core.
156  *
157  * The more_data parameter is used to notify the crypto engine
158  * that this is an "update" operation, and that more data will
159  * be provided to calculate the final hash.
160  */
161 static
162 int qcrypto_afalg_send_to_kernel(QCryptoAFAlg *afalg,
163                                  const struct iovec *iov,
164                                  size_t niov,
165                                  bool more_data,
166                                  Error **errp)
167 {
168     int ret = 0;
169     int flags = (more_data ? MSG_MORE : 0);
170 
171     /* send data to kernel's crypto core */
172     ret = iov_send_recv_with_flags(afalg->opfd, flags, iov, niov,
173                                    0, iov_size(iov, niov), true);
174     if (ret < 0) {
175         error_setg_errno(errp, errno, "Send data to afalg-core failed");
176         ret = -1;
177     } else {
178         /* No error, so return 0 */
179         ret = 0;
180     }
181 
182     return ret;
183 }
184 
185 static
186 int qcrypto_afalg_recv_from_kernel(QCryptoAFAlg *afalg,
187                                    QCryptoHashAlgo alg,
188                                    uint8_t **result,
189                                    size_t *result_len,
190                                    Error **errp)
191 {
192     struct iovec outv;
193     int ret;
194     const int expected_len = qcrypto_hash_digest_len(alg);
195 
196     if (*result_len == 0) {
197         *result_len = expected_len;
198         *result = g_new0(uint8_t, *result_len);
199     } else if (*result_len != expected_len) {
200         error_setg(errp,
201                    "Result buffer size %zu is not match hash %d",
202                    *result_len, expected_len);
203         return -1;
204     }
205 
206     /* hash && get result */
207     outv.iov_base = *result;
208     outv.iov_len = *result_len;
209     ret = iov_send_recv(afalg->opfd, &outv, 1,
210                         0, iov_size(&outv, 1), false);
211     if (ret < 0) {
212         error_setg_errno(errp, errno, "Recv result from afalg-core failed");
213         return -1;
214     }
215 
216     return 0;
217 }
218 
219 static
220 int qcrypto_afalg_hash_update(QCryptoHash *hash,
221                               const struct iovec *iov,
222                               size_t niov,
223                               Error **errp)
224 {
225     return qcrypto_afalg_send_to_kernel((QCryptoAFAlg *) hash->opaque,
226                                         iov, niov, true, errp);
227 }
228 
229 static
230 int qcrypto_afalg_hash_finalize(QCryptoHash *hash,
231                                  uint8_t **result,
232                                  size_t *result_len,
233                                  Error **errp)
234 {
235     return qcrypto_afalg_recv_from_kernel((QCryptoAFAlg *) hash->opaque,
236                                           hash->alg, result, result_len, errp);
237 }
238 
239 static int
240 qcrypto_afalg_hash_hmac_bytesv(QCryptoAFAlgo *hmac,
241                                QCryptoHashAlgo alg,
242                                const struct iovec *iov,
243                                size_t niov, uint8_t **result,
244                                size_t *resultlen,
245                                Error **errp)
246 {
247     int ret = 0;
248 
249     ret = qcrypto_afalg_send_to_kernel(hmac, iov, niov, false, errp);
250     if (ret == 0) {
251         ret = qcrypto_afalg_recv_from_kernel(hmac, alg, result,
252                                              resultlen, errp);
253     }
254 
255     return ret;
256 }
257 
258 static int
259 qcrypto_afalg_hmac_bytesv(QCryptoHmac *hmac,
260                           const struct iovec *iov,
261                           size_t niov, uint8_t **result,
262                           size_t *resultlen,
263                           Error **errp)
264 {
265     return qcrypto_afalg_hash_hmac_bytesv(hmac->opaque, hmac->alg,
266                                           iov, niov, result, resultlen,
267                                           errp);
268 }
269 
270 static void qcrypto_afalg_hmac_ctx_free(QCryptoHmac *hmac)
271 {
272     QCryptoAFAlgo *afalg;
273 
274     afalg = hmac->opaque;
275     qcrypto_afalg_comm_free(afalg);
276 }
277 
278 QCryptoHashDriver qcrypto_hash_afalg_driver = {
279     .hash_new      = qcrypto_afalg_hash_new,
280     .hash_free     = qcrypto_afalg_hash_free,
281     .hash_update   = qcrypto_afalg_hash_update,
282     .hash_finalize = qcrypto_afalg_hash_finalize
283 };
284 
285 QCryptoHmacDriver qcrypto_hmac_afalg_driver = {
286     .hmac_bytesv = qcrypto_afalg_hmac_bytesv,
287     .hmac_free = qcrypto_afalg_hmac_ctx_free,
288 };
289