io/channel-tls.c

   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 2.1 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 "qapi/error.h"
  23 #include "qemu/module.h"
  24 #include "io/channel-tls.h"
  25 #include "trace.h"
  26 #include "qemu/atomic.h"
  27
  28
  29 static ssize_t qio_channel_tls_write_handler(const char *buf,
  30                                              size_t len,
  31                                              void *opaque)
  32 {
  33     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(opaque);
  34     ssize_t ret;
  35
  36     ret = qio_channel_write(tioc->master, buf, len, NULL);
  37     if (ret == QIO_CHANNEL_ERR_BLOCK) {
  38         errno = EAGAIN;
  39         return -1;
  40     } else if (ret < 0) {
  41         errno = EIO;
  42         return -1;
  43     }
  44     return ret;
  45 }
  46
  47 static ssize_t qio_channel_tls_read_handler(char *buf,
  48                                             size_t len,
  49                                             void *opaque)
  50 {
  51     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(opaque);
  52     ssize_t ret;
  53
  54     ret = qio_channel_read(tioc->master, buf, len, NULL);
  55     if (ret == QIO_CHANNEL_ERR_BLOCK) {
  56         errno = EAGAIN;
  57         return -1;
  58     } else if (ret < 0) {
  59         errno = EIO;
  60         return -1;
  61     }
  62     return ret;
  63 }
  64
  65
  66 QIOChannelTLS *
  67 qio_channel_tls_new_server(QIOChannel *master,
  68                            QCryptoTLSCreds *creds,
  69                            const char *aclname,
  70                            Error **errp)
  71 {
  72     QIOChannelTLS *ioc;
  73
  74     ioc = QIO_CHANNEL_TLS(object_new(TYPE_QIO_CHANNEL_TLS));
  75
  76     ioc->master = master;
  77     object_ref(OBJECT(master));
  78
  79     ioc->session = qcrypto_tls_session_new(
  80         creds,
  81         NULL,
  82         aclname,
  83         QCRYPTO_TLS_CREDS_ENDPOINT_SERVER,
  84         errp);
  85     if (!ioc->session) {
  86         goto error;
  87     }
  88
  89     qcrypto_tls_session_set_callbacks(
  90         ioc->session,
  91         qio_channel_tls_write_handler,
  92         qio_channel_tls_read_handler,
  93         ioc);
  94
  95     trace_qio_channel_tls_new_server(ioc, master, creds, aclname);
  96     return ioc;
  97
  98  error:
  99     object_unref(OBJECT(ioc));
 100     return NULL;
 101 }
 102
 103 QIOChannelTLS *
 104 qio_channel_tls_new_client(QIOChannel *master,
 105                            QCryptoTLSCreds *creds,
 106                            const char *hostname,
 107                            Error **errp)
 108 {
 109     QIOChannelTLS *tioc;
 110     QIOChannel *ioc;
 111
 112     tioc = QIO_CHANNEL_TLS(object_new(TYPE_QIO_CHANNEL_TLS));
 113     ioc = QIO_CHANNEL(tioc);
 114
 115     tioc->master = master;
 116     if (qio_channel_has_feature(master, QIO_CHANNEL_FEATURE_SHUTDOWN)) {
 117         qio_channel_set_feature(ioc, QIO_CHANNEL_FEATURE_SHUTDOWN);
 118     }
 119     object_ref(OBJECT(master));
 120
 121     tioc->session = qcrypto_tls_session_new(
 122         creds,
 123         hostname,
 124         NULL,
 125         QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT,
 126         errp);
 127     if (!tioc->session) {
 128         goto error;
 129     }
 130
 131     qcrypto_tls_session_set_callbacks(
 132         tioc->session,
 133         qio_channel_tls_write_handler,
 134         qio_channel_tls_read_handler,
 135         tioc);
 136
 137     trace_qio_channel_tls_new_client(tioc, master, creds, hostname);
 138     return tioc;
 139
 140  error:
 141     object_unref(OBJECT(tioc));
 142     return NULL;
 143 }
 144
 145 struct QIOChannelTLSData {
 146     QIOTask *task;
 147     GMainContext *context;
 148 };
 149 typedef struct QIOChannelTLSData QIOChannelTLSData;
 150
 151 static gboolean qio_channel_tls_handshake_io(QIOChannel *ioc,
 152                                              GIOCondition condition,
 153                                              gpointer user_data);
 154
 155 static void qio_channel_tls_handshake_task(QIOChannelTLS *ioc,
 156                                            QIOTask *task,
 157                                            GMainContext *context)
 158 {
 159     Error *err = NULL;
 160     QCryptoTLSSessionHandshakeStatus status;
 161
 162     if (qcrypto_tls_session_handshake(ioc->session, &err) < 0) {
 163         trace_qio_channel_tls_handshake_fail(ioc);
 164         qio_task_set_error(task, err);
 165         qio_task_complete(task);
 166         return;
 167     }
 168
 169     status = qcrypto_tls_session_get_handshake_status(ioc->session);
 170     if (status == QCRYPTO_TLS_HANDSHAKE_COMPLETE) {
 171         trace_qio_channel_tls_handshake_complete(ioc);
 172         if (qcrypto_tls_session_check_credentials(ioc->session,
 173                                                   &err) < 0) {
 174             trace_qio_channel_tls_credentials_deny(ioc);
 175             qio_task_set_error(task, err);
 176         } else {
 177             trace_qio_channel_tls_credentials_allow(ioc);
 178         }
 179         qio_task_complete(task);
 180     } else {
 181         GIOCondition condition;
 182         QIOChannelTLSData *data = g_new0(typeof(*data), 1);
 183
 184         data->task = task;
 185         data->context = context;
 186
 187         if (context) {
 188             g_main_context_ref(context);
 189         }
 190
 191         if (status == QCRYPTO_TLS_HANDSHAKE_SENDING) {
 192             condition = G_IO_OUT;
 193         } else {
 194             condition = G_IO_IN;
 195         }
 196
 197         trace_qio_channel_tls_handshake_pending(ioc, status);
 198         qio_channel_add_watch_full(ioc->master,
 199                                    condition,
 200                                    qio_channel_tls_handshake_io,
 201                                    data,
 202                                    NULL,
 203                                    context);
 204     }
 205 }
 206
 207
 208 static gboolean qio_channel_tls_handshake_io(QIOChannel *ioc,
 209                                              GIOCondition condition,
 210                                              gpointer user_data)
 211 {
 212     QIOChannelTLSData *data = user_data;
 213     QIOTask *task = data->task;
 214     GMainContext *context = data->context;
 215     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(
 216         qio_task_get_source(task));
 217
 218     g_free(data);
 219     qio_channel_tls_handshake_task(tioc, task, context);
 220
 221     if (context) {
 222         g_main_context_unref(context);
 223     }
 224
 225     return FALSE;
 226 }
 227
 228 void qio_channel_tls_handshake(QIOChannelTLS *ioc,
 229                                QIOTaskFunc func,
 230                                gpointer opaque,
 231                                GDestroyNotify destroy,
 232                                GMainContext *context)
 233 {
 234     QIOTask *task;
 235
 236     task = qio_task_new(OBJECT(ioc),
 237                         func, opaque, destroy);
 238
 239     trace_qio_channel_tls_handshake_start(ioc);
 240     qio_channel_tls_handshake_task(ioc, task, context);
 241 }
 242
 243
 244 static void qio_channel_tls_init(Object *obj G_GNUC_UNUSED)
 245 {
 246 }
 247
 248
 249 static void qio_channel_tls_finalize(Object *obj)
 250 {
 251     QIOChannelTLS *ioc = QIO_CHANNEL_TLS(obj);
 252
 253     object_unref(OBJECT(ioc->master));
 254     qcrypto_tls_session_free(ioc->session);
 255 }
 256
 257
 258 static ssize_t qio_channel_tls_readv(QIOChannel *ioc,
 259                                      const struct iovec *iov,
 260                                      size_t niov,
 261                                      int **fds,
 262                                      size_t *nfds,
 263                                      Error **errp)
 264 {
 265     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(ioc);
 266     size_t i;
 267     ssize_t got = 0;
 268
 269     for (i = 0 ; i < niov ; i++) {
 270         ssize_t ret = qcrypto_tls_session_read(tioc->session,
 271                                                iov[i].iov_base,
 272                                                iov[i].iov_len);
 273         if (ret < 0) {
 274             if (errno == EAGAIN) {
 275                 if (got) {
 276                     return got;
 277                 } else {
 278                     return QIO_CHANNEL_ERR_BLOCK;
 279                 }
 280             } else if (errno == ECONNABORTED &&
 281                        (qatomic_load_acquire(&tioc->shutdown) &
 282                         QIO_CHANNEL_SHUTDOWN_READ)) {
 283                 return 0;
 284             }
 285
 286             error_setg_errno(errp, errno,
 287                              "Cannot read from TLS channel");
 288             return -1;
 289         }
 290         got += ret;
 291         if (ret < iov[i].iov_len) {
 292             break;
 293         }
 294     }
 295     return got;
 296 }
 297
 298
 299 static ssize_t qio_channel_tls_writev(QIOChannel *ioc,
 300                                       const struct iovec *iov,
 301                                       size_t niov,
 302                                       int *fds,
 303                                       size_t nfds,
 304                                       int flags,
 305                                       Error **errp)
 306 {
 307     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(ioc);
 308     size_t i;
 309     ssize_t done = 0;
 310
 311     for (i = 0 ; i < niov ; i++) {
 312         ssize_t ret = qcrypto_tls_session_write(tioc->session,
 313                                                 iov[i].iov_base,
 314                                                 iov[i].iov_len);
 315         if (ret <= 0) {
 316             if (errno == EAGAIN) {
 317                 if (done) {
 318                     return done;
 319                 } else {
 320                     return QIO_CHANNEL_ERR_BLOCK;
 321                 }
 322             }
 323
 324             error_setg_errno(errp, errno,
 325                              "Cannot write to TLS channel");
 326             return -1;
 327         }
 328         done += ret;
 329         if (ret < iov[i].iov_len) {
 330             break;
 331         }
 332     }
 333     return done;
 334 }
 335
 336 static int qio_channel_tls_set_blocking(QIOChannel *ioc,
 337                                         bool enabled,
 338                                         Error **errp)
 339 {
 340     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(ioc);
 341
 342     return qio_channel_set_blocking(tioc->master, enabled, errp);
 343 }
 344
 345 static void qio_channel_tls_set_delay(QIOChannel *ioc,
 346                                       bool enabled)
 347 {
 348     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(ioc);
 349
 350     qio_channel_set_delay(tioc->master, enabled);
 351 }
 352
 353 static void qio_channel_tls_set_cork(QIOChannel *ioc,
 354                                      bool enabled)
 355 {
 356     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(ioc);
 357
 358     qio_channel_set_cork(tioc->master, enabled);
 359 }
 360
 361 static int qio_channel_tls_shutdown(QIOChannel *ioc,
 362                                     QIOChannelShutdown how,
 363                                     Error **errp)
 364 {
 365     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(ioc);
 366
 367     qatomic_or(&tioc->shutdown, how);
 368
 369     return qio_channel_shutdown(tioc->master, how, errp);
 370 }
 371
 372 static int qio_channel_tls_close(QIOChannel *ioc,
 373                                  Error **errp)
 374 {
 375     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(ioc);
 376
 377     return qio_channel_close(tioc->master, errp);
 378 }
 379
 380 static void qio_channel_tls_set_aio_fd_handler(QIOChannel *ioc,
 381                                                AioContext *ctx,
 382                                                IOHandler *io_read,
 383                                                IOHandler *io_write,
 384                                                void *opaque)
 385 {
 386     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(ioc);
 387
 388     qio_channel_set_aio_fd_handler(tioc->master, ctx, io_read, io_write, opaque);
 389 }
 390
 391 static GSource *qio_channel_tls_create_watch(QIOChannel *ioc,
 392                                              GIOCondition condition)
 393 {
 394     QIOChannelTLS *tioc = QIO_CHANNEL_TLS(ioc);
 395
 396     return qio_channel_create_watch(tioc->master, condition);
 397 }
 398
 399 QCryptoTLSSession *
 400 qio_channel_tls_get_session(QIOChannelTLS *ioc)
 401 {
 402     return ioc->session;
 403 }
 404
 405 static void qio_channel_tls_class_init(ObjectClass *klass,
 406                                        void *class_data G_GNUC_UNUSED)
 407 {
 408     QIOChannelClass *ioc_klass = QIO_CHANNEL_CLASS(klass);
 409
 410     ioc_klass->io_writev = qio_channel_tls_writev;
 411     ioc_klass->io_readv = qio_channel_tls_readv;
 412     ioc_klass->io_set_blocking = qio_channel_tls_set_blocking;
 413     ioc_klass->io_set_delay = qio_channel_tls_set_delay;
 414     ioc_klass->io_set_cork = qio_channel_tls_set_cork;
 415     ioc_klass->io_close = qio_channel_tls_close;
 416     ioc_klass->io_shutdown = qio_channel_tls_shutdown;
 417     ioc_klass->io_create_watch = qio_channel_tls_create_watch;
 418     ioc_klass->io_set_aio_fd_handler = qio_channel_tls_set_aio_fd_handler;
 419 }
 420
 421 static const TypeInfo qio_channel_tls_info = {
 422     .parent = TYPE_QIO_CHANNEL,
 423     .name = TYPE_QIO_CHANNEL_TLS,
 424     .instance_size = sizeof(QIOChannelTLS),
 425     .instance_init = qio_channel_tls_init,
 426     .instance_finalize = qio_channel_tls_finalize,
 427     .class_init = qio_channel_tls_class_init,
 428 };
 429
 430 static void qio_channel_tls_register_types(void)
 431 {
 432     type_register_static(&qio_channel_tls_info);
 433 }
 434
 435 type_init(qio_channel_tls_register_types);