lib/vconn-stream.c

   1 /*
   2  * Copyright (c) 2008, 2009, 2010 Nicira Networks.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #include <config.h>
  18 #include <assert.h>
  19 #include <errno.h>
  20 #include <poll.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <sys/types.h>
  24 #include <unistd.h>
  25 #include "fatal-signal.h"
  26 #include "leak-checker.h"
  27 #include "ofpbuf.h"
  28 #include "openflow/openflow.h"
  29 #include "poll-loop.h"
  30 #include "socket-util.h"
  31 #include "stream.h"
  32 #include "util.h"
  33 #include "vconn-provider.h"
  34 #include "vconn.h"
  35
  36 #include "vlog.h"
  37 #define THIS_MODULE VLM_vconn_stream
  38
  39 /* Active stream socket vconn. */
  40
  41 struct vconn_stream
  42 {
  43     struct vconn vconn;
  44     struct stream *stream;
  45     struct ofpbuf *rxbuf;
  46     struct ofpbuf *txbuf;
  47 };
  48
  49 static struct vconn_class stream_vconn_class;
  50
  51 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(10, 25);
  52
  53 static void vconn_stream_clear_txbuf(struct vconn_stream *);
  54 static int count_fields(const char *);
  55
  56 static struct vconn *
  57 vconn_stream_new(struct stream *stream, int connect_status)
  58 {
  59     struct vconn_stream *s;
  60
  61     s = xmalloc(sizeof *s);
  62     vconn_init(&s->vconn, &stream_vconn_class, connect_status,
  63                stream_get_name(stream));
  64     s->stream = stream;
  65     s->txbuf = NULL;
  66     s->rxbuf = NULL;
  67     s->vconn.remote_ip = stream_get_remote_ip(stream);
  68     s->vconn.remote_port = stream_get_remote_port(stream);
  69     s->vconn.local_ip = stream_get_local_ip(stream);
  70     s->vconn.local_port = stream_get_local_port(stream);
  71     return &s->vconn;
  72 }
  73
  74 /* Creates a new vconn that will send and receive data on a stream named 'name'
  75  * and stores a pointer to the vconn in '*vconnp'.
  76  *
  77  * Returns 0 if successful, otherwise a positive errno value. */
  78 static int
  79 vconn_stream_open(const char *name_, char *suffix OVS_UNUSED,
  80                   struct vconn **vconnp)
  81 {
  82     struct stream *stream;
  83     char *name;
  84     int error;
  85
  86     if (!strncmp(name_, "tcp:", 4) && count_fields(name_) < 3) {
  87         name = xasprintf("%s:%d", name_, OFP_TCP_PORT);
  88     } else if (!strncmp(name_, "ssl:", 4) && count_fields(name_) < 3) {
  89         name = xasprintf("%s:%d", name_, OFP_SSL_PORT);
  90     } else {
  91         name = xstrdup(name_);
  92     }
  93     error = stream_open(name, &stream);
  94     free(name);
  95
  96     if (error && error != EAGAIN) {
  97         return error;
  98     }
  99
 100     *vconnp = vconn_stream_new(stream, error);
 101     return 0;
 102 }
 103
 104 static struct vconn_stream *
 105 vconn_stream_cast(struct vconn *vconn)
 106 {
 107     return CONTAINER_OF(vconn, struct vconn_stream, vconn);
 108 }
 109
 110 static void
 111 vconn_stream_close(struct vconn *vconn)
 112 {
 113     struct vconn_stream *s = vconn_stream_cast(vconn);
 114     stream_close(s->stream);
 115     vconn_stream_clear_txbuf(s);
 116     ofpbuf_delete(s->rxbuf);
 117     free(s);
 118 }
 119
 120 static int
 121 vconn_stream_connect(struct vconn *vconn)
 122 {
 123     struct vconn_stream *s = vconn_stream_cast(vconn);
 124     return stream_connect(s->stream);
 125 }
 126
 127 static int
 128 vconn_stream_recv(struct vconn *vconn, struct ofpbuf **bufferp)
 129 {
 130     struct vconn_stream *s = vconn_stream_cast(vconn);
 131     struct ofpbuf *rx;
 132     size_t want_bytes;
 133     ssize_t retval;
 134
 135     if (s->rxbuf == NULL) {
 136         s->rxbuf = ofpbuf_new(1564);
 137     }
 138     rx = s->rxbuf;
 139
 140 again:
 141     if (sizeof(struct ofp_header) > rx->size) {
 142         want_bytes = sizeof(struct ofp_header) - rx->size;
 143     } else {
 144         struct ofp_header *oh = rx->data;
 145         size_t length = ntohs(oh->length);
 146         if (length < sizeof(struct ofp_header)) {
 147             VLOG_ERR_RL(&rl, "received too-short ofp_header (%zu bytes)",
 148                         length);
 149             return EPROTO;
 150         }
 151         want_bytes = length - rx->size;
 152         if (!want_bytes) {
 153             *bufferp = rx;
 154             s->rxbuf = NULL;
 155             return 0;
 156         }
 157     }
 158     ofpbuf_prealloc_tailroom(rx, want_bytes);
 159
 160     retval = stream_recv(s->stream, ofpbuf_tail(rx), want_bytes);
 161     if (retval > 0) {
 162         rx->size += retval;
 163         if (retval == want_bytes) {
 164             if (rx->size > sizeof(struct ofp_header)) {
 165                 *bufferp = rx;
 166                 s->rxbuf = NULL;
 167                 return 0;
 168             } else {
 169                 goto again;
 170             }
 171         }
 172         return EAGAIN;
 173     } else if (retval == 0) {
 174         if (rx->size) {
 175             VLOG_ERR_RL(&rl, "connection dropped mid-packet");
 176             return EPROTO;
 177         } else {
 178             return EOF;
 179         }
 180     } else {
 181         return -retval;
 182     }
 183 }
 184
 185 static void
 186 vconn_stream_clear_txbuf(struct vconn_stream *s)
 187 {
 188     ofpbuf_delete(s->txbuf);
 189     s->txbuf = NULL;
 190 }
 191
 192 static int
 193 vconn_stream_send(struct vconn *vconn, struct ofpbuf *buffer)
 194 {
 195     struct vconn_stream *s = vconn_stream_cast(vconn);
 196     ssize_t retval;
 197
 198     if (s->txbuf) {
 199         return EAGAIN;
 200     }
 201
 202     retval = stream_send(s->stream, buffer->data, buffer->size);
 203     if (retval == buffer->size) {
 204         ofpbuf_delete(buffer);
 205         return 0;
 206     } else if (retval >= 0 || retval == -EAGAIN) {
 207         leak_checker_claim(buffer);
 208         s->txbuf = buffer;
 209         if (retval > 0) {
 210             ofpbuf_pull(buffer, retval);
 211         }
 212         return 0;
 213     } else {
 214         return -retval;
 215     }
 216 }
 217
 218 static void
 219 vconn_stream_run(struct vconn *vconn)
 220 {
 221     struct vconn_stream *s = vconn_stream_cast(vconn);
 222     ssize_t retval;
 223
 224     if (!s->txbuf) {
 225         return;
 226     }
 227
 228     retval = stream_send(s->stream, s->txbuf->data, s->txbuf->size);
 229     if (retval < 0) {
 230         if (retval != -EAGAIN) {
 231             VLOG_ERR_RL(&rl, "send: %s", strerror(-retval));
 232             vconn_stream_clear_txbuf(s);
 233             return;
 234         }
 235     } else if (retval > 0) {
 236         ofpbuf_pull(s->txbuf, retval);
 237         if (!s->txbuf->size) {
 238             vconn_stream_clear_txbuf(s);
 239             return;
 240         }
 241     }
 242 }
 243
 244 static void
 245 vconn_stream_run_wait(struct vconn *vconn)
 246 {
 247     struct vconn_stream *s = vconn_stream_cast(vconn);
 248
 249     if (s->txbuf) {
 250         stream_send_wait(s->stream);
 251     }
 252 }
 253
 254 static void
 255 vconn_stream_wait(struct vconn *vconn, enum vconn_wait_type wait)
 256 {
 257     struct vconn_stream *s = vconn_stream_cast(vconn);
 258     switch (wait) {
 259     case WAIT_CONNECT:
 260         stream_connect_wait(s->stream);
 261         break;
 262
 263     case WAIT_SEND:
 264         if (!s->txbuf) {
 265             stream_send_wait(s->stream);
 266         } else {
 267             /* Nothing to do: need to drain txbuf first.
 268              * vconn_stream_run_wait() will arrange to wake up when there room
 269              * to send data, so there's no point in calling poll_fd_wait()
 270              * redundantly here. */
 271         }
 272         break;
 273
 274     case WAIT_RECV:
 275         stream_recv_wait(s->stream);
 276         break;
 277
 278     default:
 279         NOT_REACHED();
 280     }
 281 }
 282 \f
 283 /* Passive stream socket vconn. */
 284
 285 struct pvconn_pstream
 286 {
 287     struct pvconn pvconn;
 288     struct pstream *pstream;
 289 };
 290
 291 static struct pvconn_class pstream_pvconn_class;
 292
 293 static struct pvconn_pstream *
 294 pvconn_pstream_cast(struct pvconn *pvconn)
 295 {
 296     return CONTAINER_OF(pvconn, struct pvconn_pstream, pvconn);
 297 }
 298
 299 /* Creates a new pvconn named 'name' that will accept new connections using
 300  * pstream_accept() and stores a pointer to the pvconn in '*pvconnp'.
 301  *
 302  * Returns 0 if successful, otherwise a positive errno value.  (The current
 303  * implementation never fails.) */
 304 static int
 305 pvconn_pstream_listen(const char *name_, char *suffix OVS_UNUSED,
 306                       struct pvconn **pvconnp)
 307 {
 308     struct pvconn_pstream *ps;
 309     struct pstream *pstream;
 310     char *name;
 311     int error;
 312
 313     if (!strncmp(name_, "ptcp:", 5) && count_fields(name_) < 2) {
 314         name = xasprintf("%s%d", name_, OFP_TCP_PORT);
 315     } else if (!strncmp(name_, "pssl:", 5) && count_fields(name_) < 2) {
 316         name = xasprintf("%s%d", name_, OFP_SSL_PORT);
 317     } else {
 318         name = xstrdup(name_);
 319     }
 320     error = pstream_open(name, &pstream);
 321     free(name);
 322     if (error) {
 323         return error;
 324     }
 325
 326     ps = xmalloc(sizeof *ps);
 327     pvconn_init(&ps->pvconn, &pstream_pvconn_class, name_);
 328     ps->pstream = pstream;
 329     *pvconnp = &ps->pvconn;
 330     return 0;
 331 }
 332
 333 static void
 334 pvconn_pstream_close(struct pvconn *pvconn)
 335 {
 336     struct pvconn_pstream *ps = pvconn_pstream_cast(pvconn);
 337     pstream_close(ps->pstream);
 338     free(ps);
 339 }
 340
 341 static int
 342 pvconn_pstream_accept(struct pvconn *pvconn, struct vconn **new_vconnp)
 343 {
 344     struct pvconn_pstream *ps = pvconn_pstream_cast(pvconn);
 345     struct stream *stream;
 346     int error;
 347
 348     error = pstream_accept(ps->pstream, &stream);
 349     if (error) {
 350         if (error != EAGAIN) {
 351             VLOG_DBG_RL(&rl, "%s: accept: %s",
 352                         pstream_get_name(ps->pstream), strerror(error));
 353         }
 354         return error;
 355     }
 356
 357     *new_vconnp = vconn_stream_new(stream, 0);
 358     return 0;
 359 }
 360
 361 static void
 362 pvconn_pstream_wait(struct pvconn *pvconn)
 363 {
 364     struct pvconn_pstream *ps = pvconn_pstream_cast(pvconn);
 365     pstream_wait(ps->pstream);
 366 }
 367 \f
 368 static int
 369 count_fields(const char *s_)
 370 {
 371     char *s, *field, *save_ptr;
 372     int n = 0;
 373
 374     save_ptr = NULL;
 375     s = xstrdup(s_);
 376     for (field = strtok_r(s, ":", &save_ptr); field != NULL;
 377          field = strtok_r(NULL, ":", &save_ptr)) {
 378         n++;
 379     }
 380     free(s);
 381
 382     return n;
 383 }
 384 \f
 385 /* Stream-based vconns and pvconns. */
 386
 387 #define DEFINE_VCONN_STREAM_CLASS(NAME)             \
 388         struct vconn_class NAME##_vconn_class = {   \
 389             #NAME,                                  \
 390             vconn_stream_open,                      \
 391             vconn_stream_close,                     \
 392             vconn_stream_connect,                   \
 393             vconn_stream_recv,                      \
 394             vconn_stream_send,                      \
 395             vconn_stream_run,                       \
 396             vconn_stream_run_wait,                  \
 397             vconn_stream_wait,                      \
 398         };
 399
 400 #define DEFINE_PVCONN_STREAM_CLASS(NAME)            \
 401         struct pvconn_class NAME##_pvconn_class = { \
 402             #NAME,                                  \
 403             pvconn_pstream_listen,                  \
 404             pvconn_pstream_close,                   \
 405             pvconn_pstream_accept,                  \
 406             pvconn_pstream_wait                     \
 407         };
 408
 409 static DEFINE_VCONN_STREAM_CLASS(stream);
 410 static DEFINE_PVCONN_STREAM_CLASS(pstream);
 411
 412 DEFINE_VCONN_STREAM_CLASS(tcp);
 413 DEFINE_PVCONN_STREAM_CLASS(ptcp);
 414
 415 DEFINE_VCONN_STREAM_CLASS(unix);
 416 DEFINE_PVCONN_STREAM_CLASS(punix);
 417
 418 #ifdef HAVE_OPENSSL
 419 DEFINE_VCONN_STREAM_CLASS(ssl);
 420 DEFINE_PVCONN_STREAM_CLASS(pssl);
 421 #endif