lib/vconn-stream.c

   1 /*
   2  * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013 Nicira, Inc.
   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 <errno.h>
  19 #include <poll.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <sys/types.h>
  23 #include <unistd.h>
  24 #include "fatal-signal.h"
  25 #include "ofpbuf.h"
  26 #include "openflow/openflow.h"
  27 #include "poll-loop.h"
  28 #include "socket-util.h"
  29 #include "stream.h"
  30 #include "util.h"
  31 #include "vconn-provider.h"
  32 #include "vconn.h"
  33 #include "openvswitch/vlog.h"
  34
  35 VLOG_DEFINE_THIS_MODULE(vconn_stream);
  36
  37 /* Active stream socket vconn. */
  38
  39 struct vconn_stream
  40 {
  41     struct vconn vconn;
  42     struct stream *stream;
  43     struct ofpbuf *rxbuf;
  44     struct ofpbuf *txbuf;
  45     int n_packets;
  46 };
  47
  48 static const struct vconn_class stream_vconn_class;
  49
  50 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(10, 25);
  51
  52 static void vconn_stream_clear_txbuf(struct vconn_stream *);
  53
  54 static struct vconn *
  55 vconn_stream_new(struct stream *stream, int connect_status,
  56                  uint32_t allowed_versions)
  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), allowed_versions);
  63     s->stream = stream;
  64     s->txbuf = NULL;
  65     s->rxbuf = NULL;
  66     s->n_packets = 0;
  67     return &s->vconn;
  68 }
  69
  70 /* Creates a new vconn that will send and receive data on a stream named 'name'
  71  * and stores a pointer to the vconn in '*vconnp'.
  72  *
  73  * Returns 0 if successful, otherwise a positive errno value. */
  74 static int
  75 vconn_stream_open(const char *name, uint32_t allowed_versions,
  76                   char *suffix OVS_UNUSED, struct vconn **vconnp, uint8_t dscp)
  77 {
  78     struct stream *stream;
  79     int error;
  80
  81     error = stream_open_with_default_port(name, OFP_OLD_PORT, &stream, dscp);
  82     if (!error) {
  83         error = stream_connect(stream);
  84         if (!error || error == EAGAIN) {
  85             *vconnp = vconn_stream_new(stream, error, allowed_versions);
  86             return 0;
  87         }
  88     }
  89
  90     stream_close(stream);
  91     return error;
  92 }
  93
  94 static struct vconn_stream *
  95 vconn_stream_cast(struct vconn *vconn)
  96 {
  97     return CONTAINER_OF(vconn, struct vconn_stream, vconn);
  98 }
  99
 100 static void
 101 vconn_stream_close(struct vconn *vconn)
 102 {
 103     struct vconn_stream *s = vconn_stream_cast(vconn);
 104
 105     if ((vconn->error == EPROTO || s->n_packets < 1) && s->rxbuf) {
 106         stream_report_content(ofpbuf_data(s->rxbuf), ofpbuf_size(s->rxbuf), STREAM_OPENFLOW,
 107                               THIS_MODULE, vconn_get_name(vconn));
 108     }
 109
 110     stream_close(s->stream);
 111     vconn_stream_clear_txbuf(s);
 112     ofpbuf_delete(s->rxbuf);
 113     free(s);
 114 }
 115
 116 static int
 117 vconn_stream_connect(struct vconn *vconn)
 118 {
 119     struct vconn_stream *s = vconn_stream_cast(vconn);
 120     return stream_connect(s->stream);
 121 }
 122
 123 static int
 124 vconn_stream_recv__(struct vconn_stream *s, int rx_len)
 125 {
 126     struct ofpbuf *rx = s->rxbuf;
 127     int want_bytes, retval;
 128
 129     want_bytes = rx_len - ofpbuf_size(rx);
 130     ofpbuf_prealloc_tailroom(rx, want_bytes);
 131     retval = stream_recv(s->stream, ofpbuf_tail(rx), want_bytes);
 132     if (retval > 0) {
 133         ofpbuf_set_size(rx, ofpbuf_size(rx) + retval);
 134         return retval == want_bytes ? 0 : EAGAIN;
 135     } else if (retval == 0) {
 136         if (ofpbuf_size(rx)) {
 137             VLOG_ERR_RL(&rl, "connection dropped mid-packet");
 138             return EPROTO;
 139         }
 140         return EOF;
 141     } else {
 142         return -retval;
 143     }
 144 }
 145
 146 static int
 147 vconn_stream_recv(struct vconn *vconn, struct ofpbuf **bufferp)
 148 {
 149     struct vconn_stream *s = vconn_stream_cast(vconn);
 150     const struct ofp_header *oh;
 151     int rx_len;
 152
 153     /* Allocate new receive buffer if we don't have one. */
 154     if (s->rxbuf == NULL) {
 155         s->rxbuf = ofpbuf_new(1564);
 156     }
 157
 158     /* Read ofp_header. */
 159     if (ofpbuf_size(s->rxbuf) < sizeof(struct ofp_header)) {
 160         int retval = vconn_stream_recv__(s, sizeof(struct ofp_header));
 161         if (retval) {
 162             return retval;
 163         }
 164     }
 165
 166     /* Read payload. */
 167     oh = ofpbuf_data(s->rxbuf);
 168     rx_len = ntohs(oh->length);
 169     if (rx_len < sizeof(struct ofp_header)) {
 170         VLOG_ERR_RL(&rl, "received too-short ofp_header (%d bytes)", rx_len);
 171         return EPROTO;
 172     } else if (ofpbuf_size(s->rxbuf) < rx_len) {
 173         int retval = vconn_stream_recv__(s, rx_len);
 174         if (retval) {
 175             return retval;
 176         }
 177     }
 178
 179     s->n_packets++;
 180     *bufferp = s->rxbuf;
 181     s->rxbuf = NULL;
 182     return 0;
 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, ofpbuf_data(buffer), ofpbuf_size(buffer));
 203     if (retval == ofpbuf_size(buffer)) {
 204         ofpbuf_delete(buffer);
 205         return 0;
 206     } else if (retval >= 0 || retval == -EAGAIN) {
 207         s->txbuf = buffer;
 208         if (retval > 0) {
 209             ofpbuf_pull(buffer, retval);
 210         }
 211         return 0;
 212     } else {
 213         return -retval;
 214     }
 215 }
 216
 217 static void
 218 vconn_stream_run(struct vconn *vconn)
 219 {
 220     struct vconn_stream *s = vconn_stream_cast(vconn);
 221     ssize_t retval;
 222
 223     stream_run(s->stream);
 224     if (!s->txbuf) {
 225         return;
 226     }
 227
 228     retval = stream_send(s->stream, ofpbuf_data(s->txbuf), ofpbuf_size(s->txbuf));
 229     if (retval < 0) {
 230         if (retval != -EAGAIN) {
 231             VLOG_ERR_RL(&rl, "send: %s", ovs_strerror(-retval));
 232             vconn_stream_clear_txbuf(s);
 233             return;
 234         }
 235     } else if (retval > 0) {
 236         ofpbuf_pull(s->txbuf, retval);
 237         if (!ofpbuf_size(s->txbuf)) {
 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     stream_run_wait(s->stream);
 250     if (s->txbuf) {
 251         stream_send_wait(s->stream);
 252     }
 253 }
 254
 255 static void
 256 vconn_stream_wait(struct vconn *vconn, enum vconn_wait_type wait)
 257 {
 258     struct vconn_stream *s = vconn_stream_cast(vconn);
 259     switch (wait) {
 260     case WAIT_CONNECT:
 261         stream_connect_wait(s->stream);
 262         break;
 263
 264     case WAIT_SEND:
 265         if (!s->txbuf) {
 266             stream_send_wait(s->stream);
 267         } else {
 268             /* Nothing to do: need to drain txbuf first.
 269              * vconn_stream_run_wait() will arrange to wake up when there room
 270              * to send data, so there's no point in calling poll_fd_wait()
 271              * redundantly here. */
 272         }
 273         break;
 274
 275     case WAIT_RECV:
 276         stream_recv_wait(s->stream);
 277         break;
 278
 279     default:
 280         OVS_NOT_REACHED();
 281     }
 282 }
 283 \f
 284 /* Passive stream socket vconn. */
 285
 286 struct pvconn_pstream
 287 {
 288     struct pvconn pvconn;
 289     struct pstream *pstream;
 290 };
 291
 292 static const struct pvconn_class pstream_pvconn_class;
 293
 294 static struct pvconn_pstream *
 295 pvconn_pstream_cast(struct pvconn *pvconn)
 296 {
 297     return CONTAINER_OF(pvconn, struct pvconn_pstream, pvconn);
 298 }
 299
 300 /* Creates a new pvconn named 'name' that will accept new connections using
 301  * pstream_accept() and stores a pointer to the pvconn in '*pvconnp'.
 302  *
 303  * Returns 0 if successful, otherwise a positive errno value.  (The current
 304  * implementation never fails.) */
 305 static int
 306 pvconn_pstream_listen(const char *name, uint32_t allowed_versions,
 307                       char *suffix OVS_UNUSED, struct pvconn **pvconnp,
 308                       uint8_t dscp)
 309 {
 310     struct pvconn_pstream *ps;
 311     struct pstream *pstream;
 312     int error;
 313
 314     error = pstream_open_with_default_port(name, OFP_OLD_PORT,
 315                                            &pstream, dscp);
 316     if (error) {
 317         return error;
 318     }
 319
 320     ps = xmalloc(sizeof *ps);
 321     pvconn_init(&ps->pvconn, &pstream_pvconn_class, name, allowed_versions);
 322     ps->pstream = pstream;
 323     *pvconnp = &ps->pvconn;
 324     return 0;
 325 }
 326
 327 static void
 328 pvconn_pstream_close(struct pvconn *pvconn)
 329 {
 330     struct pvconn_pstream *ps = pvconn_pstream_cast(pvconn);
 331     pstream_close(ps->pstream);
 332     free(ps);
 333 }
 334
 335 static int
 336 pvconn_pstream_accept(struct pvconn *pvconn, struct vconn **new_vconnp)
 337 {
 338     struct pvconn_pstream *ps = pvconn_pstream_cast(pvconn);
 339     struct stream *stream;
 340     int error;
 341
 342     error = pstream_accept(ps->pstream, &stream);
 343     if (error) {
 344         if (error != EAGAIN) {
 345             VLOG_DBG_RL(&rl, "%s: accept: %s",
 346                         pstream_get_name(ps->pstream), ovs_strerror(error));
 347         }
 348         return error;
 349     }
 350
 351     *new_vconnp = vconn_stream_new(stream, 0, pvconn->allowed_versions);
 352     return 0;
 353 }
 354
 355 static void
 356 pvconn_pstream_wait(struct pvconn *pvconn)
 357 {
 358     struct pvconn_pstream *ps = pvconn_pstream_cast(pvconn);
 359     pstream_wait(ps->pstream);
 360 }
 361 \f
 362 /* Stream-based vconns and pvconns. */
 363
 364 #define STREAM_INIT(NAME)                           \
 365     {                                               \
 366             NAME,                                   \
 367             vconn_stream_open,                      \
 368             vconn_stream_close,                     \
 369             vconn_stream_connect,                   \
 370             vconn_stream_recv,                      \
 371             vconn_stream_send,                      \
 372             vconn_stream_run,                       \
 373             vconn_stream_run_wait,                  \
 374             vconn_stream_wait,                      \
 375     }
 376
 377 #define PSTREAM_INIT(NAME)                          \
 378     {                                               \
 379             NAME,                                   \
 380             pvconn_pstream_listen,                  \
 381             pvconn_pstream_close,                   \
 382             pvconn_pstream_accept,                  \
 383             pvconn_pstream_wait                     \
 384     }
 385
 386 static const struct vconn_class stream_vconn_class = STREAM_INIT("stream");
 387 static const struct pvconn_class pstream_pvconn_class = PSTREAM_INIT("pstream");
 388
 389 const struct vconn_class tcp_vconn_class = STREAM_INIT("tcp");
 390 const struct pvconn_class ptcp_pvconn_class = PSTREAM_INIT("ptcp");
 391
 392 const struct vconn_class unix_vconn_class = STREAM_INIT("unix");
 393 const struct pvconn_class punix_pvconn_class = PSTREAM_INIT("punix");
 394
 395 #ifdef HAVE_OPENSSL
 396 const struct vconn_class ssl_vconn_class = STREAM_INIT("ssl");
 397 const struct pvconn_class pssl_pvconn_class = PSTREAM_INIT("pssl");
 398 #endif