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
  55 static struct vconn *
  56 vconn_stream_new(struct stream *stream, int connect_status)
  57 {
  58     struct vconn_stream *s;
  59
  60     s = xmalloc(sizeof *s);
  61     vconn_init(&s->vconn, &stream_vconn_class, connect_status,
  62                stream_get_name(stream));
  63     s->stream = stream;
  64     s->txbuf = NULL;
  65     s->rxbuf = NULL;
  66     s->vconn.remote_ip = stream_get_remote_ip(stream);
  67     s->vconn.remote_port = stream_get_remote_port(stream);
  68     s->vconn.local_ip = stream_get_local_ip(stream);
  69     s->vconn.local_port = stream_get_local_port(stream);
  70     return &s->vconn;
  71 }
  72
  73 /* Creates a new vconn that will send and receive data on a stream named 'name'
  74  * and stores a pointer to the vconn in '*vconnp'.
  75  *
  76  * Returns 0 if successful, otherwise a positive errno value. */
  77 static int
  78 vconn_stream_open(const char *name, char *suffix OVS_UNUSED,
  79                   struct vconn **vconnp)
  80 {
  81     struct stream *stream;
  82     int error;
  83
  84     error = stream_open_with_default_ports(name, OFP_TCP_PORT, OFP_SSL_PORT,
  85                                            &stream);
  86
  87     if (error && error != EAGAIN) {
  88         return error;
  89     }
  90
  91     *vconnp = vconn_stream_new(stream, error);
  92     return 0;
  93 }
  94
  95 static struct vconn_stream *
  96 vconn_stream_cast(struct vconn *vconn)
  97 {
  98     return CONTAINER_OF(vconn, struct vconn_stream, vconn);
  99 }
 100
 101 static void
 102 vconn_stream_close(struct vconn *vconn)
 103 {
 104     struct vconn_stream *s = vconn_stream_cast(vconn);
 105     stream_close(s->stream);
 106     vconn_stream_clear_txbuf(s);
 107     ofpbuf_delete(s->rxbuf);
 108     free(s);
 109 }
 110
 111 static int
 112 vconn_stream_connect(struct vconn *vconn)
 113 {
 114     struct vconn_stream *s = vconn_stream_cast(vconn);
 115     return stream_connect(s->stream);
 116 }
 117
 118 static int
 119 vconn_stream_recv(struct vconn *vconn, struct ofpbuf **bufferp)
 120 {
 121     struct vconn_stream *s = vconn_stream_cast(vconn);
 122     struct ofpbuf *rx;
 123     size_t want_bytes;
 124     ssize_t retval;
 125
 126     if (s->rxbuf == NULL) {
 127         s->rxbuf = ofpbuf_new(1564);
 128     }
 129     rx = s->rxbuf;
 130
 131 again:
 132     if (sizeof(struct ofp_header) > rx->size) {
 133         want_bytes = sizeof(struct ofp_header) - rx->size;
 134     } else {
 135         struct ofp_header *oh = rx->data;
 136         size_t length = ntohs(oh->length);
 137         if (length < sizeof(struct ofp_header)) {
 138             VLOG_ERR_RL(&rl, "received too-short ofp_header (%zu bytes)",
 139                         length);
 140             return EPROTO;
 141         }
 142         want_bytes = length - rx->size;
 143         if (!want_bytes) {
 144             *bufferp = rx;
 145             s->rxbuf = NULL;
 146             return 0;
 147         }
 148     }
 149     ofpbuf_prealloc_tailroom(rx, want_bytes);
 150
 151     retval = stream_recv(s->stream, ofpbuf_tail(rx), want_bytes);
 152     if (retval > 0) {
 153         rx->size += retval;
 154         if (retval == want_bytes) {
 155             if (rx->size > sizeof(struct ofp_header)) {
 156                 *bufferp = rx;
 157                 s->rxbuf = NULL;
 158                 return 0;
 159             } else {
 160                 goto again;
 161             }
 162         }
 163         return EAGAIN;
 164     } else if (retval == 0) {
 165         if (rx->size) {
 166             VLOG_ERR_RL(&rl, "connection dropped mid-packet");
 167             return EPROTO;
 168         } else {
 169             return EOF;
 170         }
 171     } else {
 172         return -retval;
 173     }
 174 }
 175
 176 static void
 177 vconn_stream_clear_txbuf(struct vconn_stream *s)
 178 {
 179     ofpbuf_delete(s->txbuf);
 180     s->txbuf = NULL;
 181 }
 182
 183 static int
 184 vconn_stream_send(struct vconn *vconn, struct ofpbuf *buffer)
 185 {
 186     struct vconn_stream *s = vconn_stream_cast(vconn);
 187     ssize_t retval;
 188
 189     if (s->txbuf) {
 190         return EAGAIN;
 191     }
 192
 193     retval = stream_send(s->stream, buffer->data, buffer->size);
 194     if (retval == buffer->size) {
 195         ofpbuf_delete(buffer);
 196         return 0;
 197     } else if (retval >= 0 || retval == -EAGAIN) {
 198         leak_checker_claim(buffer);
 199         s->txbuf = buffer;
 200         if (retval > 0) {
 201             ofpbuf_pull(buffer, retval);
 202         }
 203         return 0;
 204     } else {
 205         return -retval;
 206     }
 207 }
 208
 209 static void
 210 vconn_stream_run(struct vconn *vconn)
 211 {
 212     struct vconn_stream *s = vconn_stream_cast(vconn);
 213     ssize_t retval;
 214
 215     if (!s->txbuf) {
 216         return;
 217     }
 218
 219     retval = stream_send(s->stream, s->txbuf->data, s->txbuf->size);
 220     if (retval < 0) {
 221         if (retval != -EAGAIN) {
 222             VLOG_ERR_RL(&rl, "send: %s", strerror(-retval));
 223             vconn_stream_clear_txbuf(s);
 224             return;
 225         }
 226     } else if (retval > 0) {
 227         ofpbuf_pull(s->txbuf, retval);
 228         if (!s->txbuf->size) {
 229             vconn_stream_clear_txbuf(s);
 230             return;
 231         }
 232     }
 233 }
 234
 235 static void
 236 vconn_stream_run_wait(struct vconn *vconn)
 237 {
 238     struct vconn_stream *s = vconn_stream_cast(vconn);
 239
 240     if (s->txbuf) {
 241         stream_send_wait(s->stream);
 242     }
 243 }
 244
 245 static void
 246 vconn_stream_wait(struct vconn *vconn, enum vconn_wait_type wait)
 247 {
 248     struct vconn_stream *s = vconn_stream_cast(vconn);
 249     switch (wait) {
 250     case WAIT_CONNECT:
 251         stream_connect_wait(s->stream);
 252         break;
 253
 254     case WAIT_SEND:
 255         if (!s->txbuf) {
 256             stream_send_wait(s->stream);
 257         } else {
 258             /* Nothing to do: need to drain txbuf first.
 259              * vconn_stream_run_wait() will arrange to wake up when there room
 260              * to send data, so there's no point in calling poll_fd_wait()
 261              * redundantly here. */
 262         }
 263         break;
 264
 265     case WAIT_RECV:
 266         stream_recv_wait(s->stream);
 267         break;
 268
 269     default:
 270         NOT_REACHED();
 271     }
 272 }
 273 \f
 274 /* Passive stream socket vconn. */
 275
 276 struct pvconn_pstream
 277 {
 278     struct pvconn pvconn;
 279     struct pstream *pstream;
 280 };
 281
 282 static struct pvconn_class pstream_pvconn_class;
 283
 284 static struct pvconn_pstream *
 285 pvconn_pstream_cast(struct pvconn *pvconn)
 286 {
 287     return CONTAINER_OF(pvconn, struct pvconn_pstream, pvconn);
 288 }
 289
 290 /* Creates a new pvconn named 'name' that will accept new connections using
 291  * pstream_accept() and stores a pointer to the pvconn in '*pvconnp'.
 292  *
 293  * Returns 0 if successful, otherwise a positive errno value.  (The current
 294  * implementation never fails.) */
 295 static int
 296 pvconn_pstream_listen(const char *name, char *suffix OVS_UNUSED,
 297                       struct pvconn **pvconnp)
 298 {
 299     struct pvconn_pstream *ps;
 300     struct pstream *pstream;
 301     int error;
 302
 303     error = pstream_open_with_default_ports(name, OFP_TCP_PORT, OFP_SSL_PORT,
 304                                             &pstream);
 305     if (error) {
 306         return error;
 307     }
 308
 309     ps = xmalloc(sizeof *ps);
 310     pvconn_init(&ps->pvconn, &pstream_pvconn_class, name);
 311     ps->pstream = pstream;
 312     *pvconnp = &ps->pvconn;
 313     return 0;
 314 }
 315
 316 static void
 317 pvconn_pstream_close(struct pvconn *pvconn)
 318 {
 319     struct pvconn_pstream *ps = pvconn_pstream_cast(pvconn);
 320     pstream_close(ps->pstream);
 321     free(ps);
 322 }
 323
 324 static int
 325 pvconn_pstream_accept(struct pvconn *pvconn, struct vconn **new_vconnp)
 326 {
 327     struct pvconn_pstream *ps = pvconn_pstream_cast(pvconn);
 328     struct stream *stream;
 329     int error;
 330
 331     error = pstream_accept(ps->pstream, &stream);
 332     if (error) {
 333         if (error != EAGAIN) {
 334             VLOG_DBG_RL(&rl, "%s: accept: %s",
 335                         pstream_get_name(ps->pstream), strerror(error));
 336         }
 337         return error;
 338     }
 339
 340     *new_vconnp = vconn_stream_new(stream, 0);
 341     return 0;
 342 }
 343
 344 static void
 345 pvconn_pstream_wait(struct pvconn *pvconn)
 346 {
 347     struct pvconn_pstream *ps = pvconn_pstream_cast(pvconn);
 348     pstream_wait(ps->pstream);
 349 }
 350 \f
 351 /* Stream-based vconns and pvconns. */
 352
 353 #define DEFINE_VCONN_STREAM_CLASS(NAME)             \
 354         struct vconn_class NAME##_vconn_class = {   \
 355             #NAME,                                  \
 356             vconn_stream_open,                      \
 357             vconn_stream_close,                     \
 358             vconn_stream_connect,                   \
 359             vconn_stream_recv,                      \
 360             vconn_stream_send,                      \
 361             vconn_stream_run,                       \
 362             vconn_stream_run_wait,                  \
 363             vconn_stream_wait,                      \
 364         };
 365
 366 #define DEFINE_PVCONN_STREAM_CLASS(NAME)            \
 367         struct pvconn_class NAME##_pvconn_class = { \
 368             #NAME,                                  \
 369             pvconn_pstream_listen,                  \
 370             pvconn_pstream_close,                   \
 371             pvconn_pstream_accept,                  \
 372             pvconn_pstream_wait                     \
 373         };
 374
 375 static DEFINE_VCONN_STREAM_CLASS(stream);
 376 static DEFINE_PVCONN_STREAM_CLASS(pstream);
 377
 378 DEFINE_VCONN_STREAM_CLASS(tcp);
 379 DEFINE_PVCONN_STREAM_CLASS(ptcp);
 380
 381 DEFINE_VCONN_STREAM_CLASS(unix);
 382 DEFINE_PVCONN_STREAM_CLASS(punix);
 383
 384 #ifdef HAVE_OPENSSL
 385 DEFINE_VCONN_STREAM_CLASS(ssl);
 386 DEFINE_PVCONN_STREAM_CLASS(pssl);
 387 #endif