Merge tag 'for-upstream' of git://repo.or.cz/qemu/kevin into staging
[qemu.git] / crypto / tlscredspsk.c
1 /*
2 * QEMU crypto TLS Pre-Shared Keys (PSK) support
3 *
4 * Copyright (c) 2018 Red Hat, Inc.
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18 *
19 */
20
21 #include "qemu/osdep.h"
22 #include "crypto/tlscredspsk.h"
23 #include "tlscredspriv.h"
24 #include "qapi/error.h"
25 #include "qemu/module.h"
26 #include "qom/object_interfaces.h"
27 #include "trace.h"
28
29
30 #ifdef CONFIG_GNUTLS
31
32 #include <gnutls/gnutls.h>
33
34 static int
35 lookup_key(const char *pskfile, const char *username, gnutls_datum_t *key,
36 Error **errp)
37 {
38 const size_t ulen = strlen(username);
39 GError *gerr = NULL;
40 char *content = NULL;
41 char **lines = NULL;
42 size_t clen = 0, i;
43 int ret = -1;
44
45 if (!g_file_get_contents(pskfile, &content, &clen, &gerr)) {
46 error_setg(errp, "Cannot read PSK file %s: %s",
47 pskfile, gerr->message);
48 g_error_free(gerr);
49 return -1;
50 }
51
52 lines = g_strsplit(content, "\n", -1);
53 for (i = 0; lines[i] != NULL; ++i) {
54 if (strncmp(lines[i], username, ulen) == 0 && lines[i][ulen] == ':') {
55 key->data = (unsigned char *) g_strdup(&lines[i][ulen + 1]);
56 key->size = strlen(lines[i]) - ulen - 1;
57 ret = 0;
58 goto out;
59 }
60 }
61 error_setg(errp, "Username %s not found in PSK file %s",
62 username, pskfile);
63
64 out:
65 free(content);
66 g_strfreev(lines);
67 return ret;
68 }
69
70 static int
71 qcrypto_tls_creds_psk_load(QCryptoTLSCredsPSK *creds,
72 Error **errp)
73 {
74 g_autofree char *pskfile = NULL;
75 g_autofree char *dhparams = NULL;
76 const char *username;
77 int ret;
78 int rv = -1;
79 gnutls_datum_t key = { .data = NULL };
80
81 trace_qcrypto_tls_creds_psk_load(creds,
82 creds->parent_obj.dir ? creds->parent_obj.dir : "<nodir>");
83
84 if (creds->parent_obj.endpoint == QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) {
85 if (creds->username) {
86 error_setg(errp, "username should not be set when endpoint=server");
87 goto cleanup;
88 }
89
90 if (qcrypto_tls_creds_get_path(&creds->parent_obj,
91 QCRYPTO_TLS_CREDS_DH_PARAMS,
92 false, &dhparams, errp) < 0 ||
93 qcrypto_tls_creds_get_path(&creds->parent_obj,
94 QCRYPTO_TLS_CREDS_PSKFILE,
95 true, &pskfile, errp) < 0) {
96 goto cleanup;
97 }
98
99 ret = gnutls_psk_allocate_server_credentials(&creds->data.server);
100 if (ret < 0) {
101 error_setg(errp, "Cannot allocate credentials: %s",
102 gnutls_strerror(ret));
103 goto cleanup;
104 }
105
106 if (qcrypto_tls_creds_get_dh_params_file(&creds->parent_obj, dhparams,
107 &creds->parent_obj.dh_params,
108 errp) < 0) {
109 goto cleanup;
110 }
111
112 gnutls_psk_set_server_credentials_file(creds->data.server, pskfile);
113 gnutls_psk_set_server_dh_params(creds->data.server,
114 creds->parent_obj.dh_params);
115 } else {
116 if (qcrypto_tls_creds_get_path(&creds->parent_obj,
117 QCRYPTO_TLS_CREDS_PSKFILE,
118 true, &pskfile, errp) < 0) {
119 goto cleanup;
120 }
121
122 if (creds->username) {
123 username = creds->username;
124 } else {
125 username = "qemu";
126 }
127 if (lookup_key(pskfile, username, &key, errp) != 0) {
128 goto cleanup;
129 }
130
131 ret = gnutls_psk_allocate_client_credentials(&creds->data.client);
132 if (ret < 0) {
133 error_setg(errp, "Cannot allocate credentials: %s",
134 gnutls_strerror(ret));
135 goto cleanup;
136 }
137
138 gnutls_psk_set_client_credentials(creds->data.client,
139 username, &key, GNUTLS_PSK_KEY_HEX);
140 }
141
142 rv = 0;
143 cleanup:
144 g_free(key.data);
145 return rv;
146 }
147
148
149 static void
150 qcrypto_tls_creds_psk_unload(QCryptoTLSCredsPSK *creds)
151 {
152 if (creds->parent_obj.endpoint == QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) {
153 if (creds->data.client) {
154 gnutls_psk_free_client_credentials(creds->data.client);
155 creds->data.client = NULL;
156 }
157 } else {
158 if (creds->data.server) {
159 gnutls_psk_free_server_credentials(creds->data.server);
160 creds->data.server = NULL;
161 }
162 }
163 if (creds->parent_obj.dh_params) {
164 gnutls_dh_params_deinit(creds->parent_obj.dh_params);
165 creds->parent_obj.dh_params = NULL;
166 }
167 }
168
169 #else /* ! CONFIG_GNUTLS */
170
171
172 static void
173 qcrypto_tls_creds_psk_load(QCryptoTLSCredsPSK *creds G_GNUC_UNUSED,
174 Error **errp)
175 {
176 error_setg(errp, "TLS credentials support requires GNUTLS");
177 }
178
179
180 static void
181 qcrypto_tls_creds_psk_unload(QCryptoTLSCredsPSK *creds G_GNUC_UNUSED)
182 {
183 /* nada */
184 }
185
186
187 #endif /* ! CONFIG_GNUTLS */
188
189
190 static void
191 qcrypto_tls_creds_psk_complete(UserCreatable *uc, Error **errp)
192 {
193 QCryptoTLSCredsPSK *creds = QCRYPTO_TLS_CREDS_PSK(uc);
194
195 qcrypto_tls_creds_psk_load(creds, errp);
196 }
197
198
199 #ifdef CONFIG_GNUTLS
200
201
202 static bool
203 qcrypto_tls_creds_psk_prop_get_loaded(Object *obj,
204 Error **errp G_GNUC_UNUSED)
205 {
206 QCryptoTLSCredsPSK *creds = QCRYPTO_TLS_CREDS_PSK(obj);
207
208 if (creds->parent_obj.endpoint == QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) {
209 return creds->data.server != NULL;
210 } else {
211 return creds->data.client != NULL;
212 }
213 }
214
215
216 #else /* ! CONFIG_GNUTLS */
217
218
219 static bool
220 qcrypto_tls_creds_psk_prop_get_loaded(Object *obj G_GNUC_UNUSED,
221 Error **errp G_GNUC_UNUSED)
222 {
223 return false;
224 }
225
226
227 #endif /* ! CONFIG_GNUTLS */
228
229
230 static void
231 qcrypto_tls_creds_psk_finalize(Object *obj)
232 {
233 QCryptoTLSCredsPSK *creds = QCRYPTO_TLS_CREDS_PSK(obj);
234
235 qcrypto_tls_creds_psk_unload(creds);
236 }
237
238 static void
239 qcrypto_tls_creds_psk_prop_set_username(Object *obj,
240 const char *value,
241 Error **errp G_GNUC_UNUSED)
242 {
243 QCryptoTLSCredsPSK *creds = QCRYPTO_TLS_CREDS_PSK(obj);
244
245 creds->username = g_strdup(value);
246 }
247
248
249 static char *
250 qcrypto_tls_creds_psk_prop_get_username(Object *obj,
251 Error **errp G_GNUC_UNUSED)
252 {
253 QCryptoTLSCredsPSK *creds = QCRYPTO_TLS_CREDS_PSK(obj);
254
255 return g_strdup(creds->username);
256 }
257
258 static void
259 qcrypto_tls_creds_psk_class_init(ObjectClass *oc, void *data)
260 {
261 UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
262
263 ucc->complete = qcrypto_tls_creds_psk_complete;
264
265 object_class_property_add_bool(oc, "loaded",
266 qcrypto_tls_creds_psk_prop_get_loaded,
267 NULL);
268 object_class_property_add_str(oc, "username",
269 qcrypto_tls_creds_psk_prop_get_username,
270 qcrypto_tls_creds_psk_prop_set_username);
271 }
272
273
274 static const TypeInfo qcrypto_tls_creds_psk_info = {
275 .parent = TYPE_QCRYPTO_TLS_CREDS,
276 .name = TYPE_QCRYPTO_TLS_CREDS_PSK,
277 .instance_size = sizeof(QCryptoTLSCredsPSK),
278 .instance_finalize = qcrypto_tls_creds_psk_finalize,
279 .class_size = sizeof(QCryptoTLSCredsPSKClass),
280 .class_init = qcrypto_tls_creds_psk_class_init,
281 .interfaces = (InterfaceInfo[]) {
282 { TYPE_USER_CREATABLE },
283 { }
284 }
285 };
286
287
288 static void
289 qcrypto_tls_creds_psk_register_types(void)
290 {
291 type_register_static(&qcrypto_tls_creds_psk_info);
292 }
293
294
295 type_init(qcrypto_tls_creds_psk_register_types);