xref: /openbmc/qemu/io/channel-tls.c (revision 84a3a53c)
1 /*
2  * QEMU I/O channels TLS driver
3  *
4  * Copyright (c) 2015 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 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 "io/channel-tls.h"
22 #include "trace.h"
23 
24 
25 static ssize_t qio_channel_tls_write_handler(const char *buf,
26                                              size_t len,
27                                              void *opaque)
28 {
29     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(opaque);
30     ssize_t ret;
31 
32     ret = qio_channel_write(tioc->master, buf, len, NULL);
33     if (ret == QIO_CHANNEL_ERR_BLOCK) {
34         errno = EAGAIN;
35         return -1;
36     } else if (ret < 0) {
37         errno = EIO;
38         return -1;
39     }
40     return ret;
41 }
42 
43 static ssize_t qio_channel_tls_read_handler(char *buf,
44                                             size_t len,
45                                             void *opaque)
46 {
47     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(opaque);
48     ssize_t ret;
49 
50     ret = qio_channel_read(tioc->master, buf, len, NULL);
51     if (ret == QIO_CHANNEL_ERR_BLOCK) {
52         errno = EAGAIN;
53         return -1;
54     } else if (ret < 0) {
55         errno = EIO;
56         return -1;
57     }
58     return ret;
59 }
60 
61 
62 QIOChannelTLS *
63 qio_channel_tls_new_server(QIOChannel *master,
64                            QCryptoTLSCreds *creds,
65                            const char *aclname,
66                            Error **errp)
67 {
68     QIOChannelTLS *ioc;
69 
70     ioc = QIO_CHANNEL_TLS(object_new(TYPE_QIO_CHANNEL_TLS));
71 
72     ioc->master = master;
73     object_ref(OBJECT(master));
74 
75     ioc->session = qcrypto_tls_session_new(
76         creds,
77         NULL,
78         aclname,
79         QCRYPTO_TLS_CREDS_ENDPOINT_SERVER,
80         errp);
81     if (!ioc->session) {
82         goto error;
83     }
84 
85     qcrypto_tls_session_set_callbacks(
86         ioc->session,
87         qio_channel_tls_write_handler,
88         qio_channel_tls_read_handler,
89         ioc);
90 
91     trace_qio_channel_tls_new_server(ioc, master, creds, aclname);
92     return ioc;
93 
94  error:
95     object_unref(OBJECT(ioc));
96     return NULL;
97 }
98 
99 QIOChannelTLS *
100 qio_channel_tls_new_client(QIOChannel *master,
101                            QCryptoTLSCreds *creds,
102                            const char *hostname,
103                            Error **errp)
104 {
105     QIOChannelTLS *tioc;
106     QIOChannel *ioc;
107 
108     tioc = QIO_CHANNEL_TLS(object_new(TYPE_QIO_CHANNEL_TLS));
109     ioc = QIO_CHANNEL(tioc);
110 
111     tioc->master = master;
112     if (master->features & (1 << QIO_CHANNEL_FEATURE_SHUTDOWN)) {
113         ioc->features |= (1 << QIO_CHANNEL_FEATURE_SHUTDOWN);
114     }
115     object_ref(OBJECT(master));
116 
117     tioc->session = qcrypto_tls_session_new(
118         creds,
119         hostname,
120         NULL,
121         QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT,
122         errp);
123     if (!tioc->session) {
124         goto error;
125     }
126 
127     qcrypto_tls_session_set_callbacks(
128         tioc->session,
129         qio_channel_tls_write_handler,
130         qio_channel_tls_read_handler,
131         tioc);
132 
133     trace_qio_channel_tls_new_client(tioc, master, creds, hostname);
134     return tioc;
135 
136  error:
137     object_unref(OBJECT(tioc));
138     return NULL;
139 }
140 
141 
142 static gboolean qio_channel_tls_handshake_io(QIOChannel *ioc,
143                                              GIOCondition condition,
144                                              gpointer user_data);
145 
146 static void qio_channel_tls_handshake_task(QIOChannelTLS *ioc,
147                                            QIOTask *task)
148 {
149     Error *err = NULL;
150     QCryptoTLSSessionHandshakeStatus status;
151 
152     if (qcrypto_tls_session_handshake(ioc->session, &err) < 0) {
153         trace_qio_channel_tls_handshake_fail(ioc);
154         qio_task_abort(task, err);
155         goto cleanup;
156     }
157 
158     status = qcrypto_tls_session_get_handshake_status(ioc->session);
159     if (status == QCRYPTO_TLS_HANDSHAKE_COMPLETE) {
160         trace_qio_channel_tls_handshake_complete(ioc);
161         if (qcrypto_tls_session_check_credentials(ioc->session,
162                                                   &err) < 0) {
163             trace_qio_channel_tls_credentials_deny(ioc);
164             qio_task_abort(task, err);
165             goto cleanup;
166         }
167         trace_qio_channel_tls_credentials_allow(ioc);
168         qio_task_complete(task);
169     } else {
170         GIOCondition condition;
171         if (status == QCRYPTO_TLS_HANDSHAKE_SENDING) {
172             condition = G_IO_OUT;
173         } else {
174             condition = G_IO_IN;
175         }
176 
177         trace_qio_channel_tls_handshake_pending(ioc, status);
178         qio_channel_add_watch(ioc->master,
179                               condition,
180                               qio_channel_tls_handshake_io,
181                               task,
182                               NULL);
183     }
184 
185  cleanup:
186     error_free(err);
187 }
188 
189 
190 static gboolean qio_channel_tls_handshake_io(QIOChannel *ioc,
191                                              GIOCondition condition,
192                                              gpointer user_data)
193 {
194     QIOTask *task = user_data;
195     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(
196         qio_task_get_source(task));
197 
198     qio_channel_tls_handshake_task(
199        tioc, task);
200 
201     object_unref(OBJECT(tioc));
202 
203     return FALSE;
204 }
205 
206 void qio_channel_tls_handshake(QIOChannelTLS *ioc,
207                                QIOTaskFunc func,
208                                gpointer opaque,
209                                GDestroyNotify destroy)
210 {
211     QIOTask *task;
212 
213     task = qio_task_new(OBJECT(ioc),
214                         func, opaque, destroy);
215 
216     trace_qio_channel_tls_handshake_start(ioc);
217     qio_channel_tls_handshake_task(ioc, task);
218 }
219 
220 
221 static void qio_channel_tls_init(Object *obj G_GNUC_UNUSED)
222 {
223 }
224 
225 
226 static void qio_channel_tls_finalize(Object *obj)
227 {
228     QIOChannelTLS *ioc = QIO_CHANNEL_TLS(obj);
229 
230     object_unref(OBJECT(ioc->master));
231     qcrypto_tls_session_free(ioc->session);
232 }
233 
234 
235 static ssize_t qio_channel_tls_readv(QIOChannel *ioc,
236                                      const struct iovec *iov,
237                                      size_t niov,
238                                      int **fds,
239                                      size_t *nfds,
240                                      Error **errp)
241 {
242     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(ioc);
243     size_t i;
244     ssize_t got = 0;
245 
246     for (i = 0 ; i < niov ; i++) {
247         ssize_t ret = qcrypto_tls_session_read(tioc->session,
248                                                iov[i].iov_base,
249                                                iov[i].iov_len);
250         if (ret < 0) {
251             if (errno == EAGAIN) {
252                 if (got) {
253                     return got;
254                 } else {
255                     return QIO_CHANNEL_ERR_BLOCK;
256                 }
257             }
258 
259             error_setg_errno(errp, errno,
260                              "Cannot read from TLS channel");
261             return -1;
262         }
263         got += ret;
264         if (ret < iov[i].iov_len) {
265             break;
266         }
267     }
268     return got;
269 }
270 
271 
272 static ssize_t qio_channel_tls_writev(QIOChannel *ioc,
273                                       const struct iovec *iov,
274                                       size_t niov,
275                                       int *fds,
276                                       size_t nfds,
277                                       Error **errp)
278 {
279     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(ioc);
280     size_t i;
281     ssize_t done = 0;
282 
283     for (i = 0 ; i < niov ; i++) {
284         ssize_t ret = qcrypto_tls_session_write(tioc->session,
285                                                 iov[i].iov_base,
286                                                 iov[i].iov_len);
287         if (ret <= 0) {
288             if (errno == EAGAIN) {
289                 if (done) {
290                     return done;
291                 } else {
292                     return QIO_CHANNEL_ERR_BLOCK;
293                 }
294             }
295 
296             error_setg_errno(errp, errno,
297                              "Cannot write to TLS channel");
298             return -1;
299         }
300         done += ret;
301         if (ret < iov[i].iov_len) {
302             break;
303         }
304     }
305     return done;
306 }
307 
308 static int qio_channel_tls_set_blocking(QIOChannel *ioc,
309                                         bool enabled,
310                                         Error **errp)
311 {
312     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(ioc);
313 
314     return qio_channel_set_blocking(tioc->master, enabled, errp);
315 }
316 
317 static void qio_channel_tls_set_delay(QIOChannel *ioc,
318                                       bool enabled)
319 {
320     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(ioc);
321 
322     qio_channel_set_delay(tioc->master, enabled);
323 }
324 
325 static void qio_channel_tls_set_cork(QIOChannel *ioc,
326                                      bool enabled)
327 {
328     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(ioc);
329 
330     qio_channel_set_cork(tioc->master, enabled);
331 }
332 
333 static int qio_channel_tls_shutdown(QIOChannel *ioc,
334                                     QIOChannelShutdown how,
335                                     Error **errp)
336 {
337     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(ioc);
338 
339     return qio_channel_shutdown(tioc->master, how, errp);
340 }
341 
342 static int qio_channel_tls_close(QIOChannel *ioc,
343                                  Error **errp)
344 {
345     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(ioc);
346 
347     return qio_channel_close(tioc->master, errp);
348 }
349 
350 static GSource *qio_channel_tls_create_watch(QIOChannel *ioc,
351                                              GIOCondition condition)
352 {
353     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(ioc);
354 
355     return qio_channel_create_watch(tioc->master, condition);
356 }
357 
358 QCryptoTLSSession *
359 qio_channel_tls_get_session(QIOChannelTLS *ioc)
360 {
361     return ioc->session;
362 }
363 
364 static void qio_channel_tls_class_init(ObjectClass *klass,
365                                        void *class_data G_GNUC_UNUSED)
366 {
367     QIOChannelClass *ioc_klass = QIO_CHANNEL_CLASS(klass);
368 
369     ioc_klass->io_writev = qio_channel_tls_writev;
370     ioc_klass->io_readv = qio_channel_tls_readv;
371     ioc_klass->io_set_blocking = qio_channel_tls_set_blocking;
372     ioc_klass->io_set_delay = qio_channel_tls_set_delay;
373     ioc_klass->io_set_cork = qio_channel_tls_set_cork;
374     ioc_klass->io_close = qio_channel_tls_close;
375     ioc_klass->io_shutdown = qio_channel_tls_shutdown;
376     ioc_klass->io_create_watch = qio_channel_tls_create_watch;
377 }
378 
379 static const TypeInfo qio_channel_tls_info = {
380     .parent = TYPE_QIO_CHANNEL,
381     .name = TYPE_QIO_CHANNEL_TLS,
382     .instance_size = sizeof(QIOChannelTLS),
383     .instance_init = qio_channel_tls_init,
384     .instance_finalize = qio_channel_tls_finalize,
385     .class_init = qio_channel_tls_class_init,
386 };
387 
388 static void qio_channel_tls_register_types(void)
389 {
390     type_register_static(&qio_channel_tls_info);
391 }
392 
393 type_init(qio_channel_tls_register_types);
394