net/socket.c

   1 /*
   2  * QEMU System Emulator
   3  *
   4  * Copyright (c) 2003-2008 Fabrice Bellard
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24 #include "config-host.h"
  25
  26 #include "net/net.h"
  27 #include "clients.h"
  28 #include "monitor/monitor.h"
  29 #include "qemu-common.h"
  30 #include "qemu/error-report.h"
  31 #include "qemu/option.h"
  32 #include "qemu/sockets.h"
  33 #include "qemu/iov.h"
  34 #include "qemu/main-loop.h"
  35
  36 typedef struct NetSocketState {
  37     NetClientState nc;
  38     int listen_fd;
  39     int fd;
  40     int state; /* 0 = getting length, 1 = getting data */
  41     unsigned int index;
  42     unsigned int packet_len;
  43     unsigned int send_index;      /* number of bytes sent (only SOCK_STREAM) */
  44     uint8_t buf[NET_BUFSIZE];
  45     struct sockaddr_in dgram_dst; /* contains inet host and port destination iff connectionless (SOCK_DGRAM) */
  46     IOHandler *send_fn;           /* differs between SOCK_STREAM/SOCK_DGRAM */
  47     bool read_poll;               /* waiting to receive data? */
  48     bool write_poll;              /* waiting to transmit data? */
  49 } NetSocketState;
  50
  51 static void net_socket_accept(void *opaque);
  52 static void net_socket_writable(void *opaque);
  53
  54 /* Only read packets from socket when peer can receive them */
  55 static int net_socket_can_send(void *opaque)
  56 {
  57     NetSocketState *s = opaque;
  58
  59     return qemu_can_send_packet(&s->nc);
  60 }
  61
  62 static void net_socket_update_fd_handler(NetSocketState *s)
  63 {
  64     qemu_set_fd_handler2(s->fd,
  65                          s->read_poll  ? net_socket_can_send : NULL,
  66                          s->read_poll  ? s->send_fn : NULL,
  67                          s->write_poll ? net_socket_writable : NULL,
  68                          s);
  69 }
  70
  71 static void net_socket_read_poll(NetSocketState *s, bool enable)
  72 {
  73     s->read_poll = enable;
  74     net_socket_update_fd_handler(s);
  75 }
  76
  77 static void net_socket_write_poll(NetSocketState *s, bool enable)
  78 {
  79     s->write_poll = enable;
  80     net_socket_update_fd_handler(s);
  81 }
  82
  83 static void net_socket_writable(void *opaque)
  84 {
  85     NetSocketState *s = opaque;
  86
  87     net_socket_write_poll(s, false);
  88
  89     qemu_flush_queued_packets(&s->nc);
  90 }
  91
  92 static ssize_t net_socket_receive(NetClientState *nc, const uint8_t *buf, size_t size)
  93 {
  94     NetSocketState *s = DO_UPCAST(NetSocketState, nc, nc);
  95     uint32_t len = htonl(size);
  96     struct iovec iov[] = {
  97         {
  98             .iov_base = &len,
  99             .iov_len  = sizeof(len),
 100         }, {
 101             .iov_base = (void *)buf,
 102             .iov_len  = size,
 103         },
 104     };
 105     size_t remaining;
 106     ssize_t ret;
 107
 108     remaining = iov_size(iov, 2) - s->send_index;
 109     ret = iov_send(s->fd, iov, 2, s->send_index, remaining);
 110
 111     if (ret == -1 && errno == EAGAIN) {
 112         ret = 0; /* handled further down */
 113     }
 114     if (ret == -1) {
 115         s->send_index = 0;
 116         return -errno;
 117     }
 118     if (ret < (ssize_t)remaining) {
 119         s->send_index += ret;
 120         net_socket_write_poll(s, true);
 121         return 0;
 122     }
 123     s->send_index = 0;
 124     return size;
 125 }
 126
 127 static ssize_t net_socket_receive_dgram(NetClientState *nc, const uint8_t *buf, size_t size)
 128 {
 129     NetSocketState *s = DO_UPCAST(NetSocketState, nc, nc);
 130     ssize_t ret;
 131
 132     do {
 133         ret = qemu_sendto(s->fd, buf, size, 0,
 134                           (struct sockaddr *)&s->dgram_dst,
 135                           sizeof(s->dgram_dst));
 136     } while (ret == -1 && errno == EINTR);
 137
 138     if (ret == -1 && errno == EAGAIN) {
 139         net_socket_write_poll(s, true);
 140         return 0;
 141     }
 142     return ret;
 143 }
 144
 145 static void net_socket_send(void *opaque)
 146 {
 147     NetSocketState *s = opaque;
 148     int size, err;
 149     unsigned l;
 150     uint8_t buf1[NET_BUFSIZE];
 151     const uint8_t *buf;
 152
 153     size = qemu_recv(s->fd, buf1, sizeof(buf1), 0);
 154     if (size < 0) {
 155         err = socket_error();
 156         if (err != EWOULDBLOCK)
 157             goto eoc;
 158     } else if (size == 0) {
 159         /* end of connection */
 160     eoc:
 161         net_socket_read_poll(s, false);
 162         net_socket_write_poll(s, false);
 163         if (s->listen_fd != -1) {
 164             qemu_set_fd_handler(s->listen_fd, net_socket_accept, NULL, s);
 165         }
 166         closesocket(s->fd);
 167
 168         s->fd = -1;
 169         s->state = 0;
 170         s->index = 0;
 171         s->packet_len = 0;
 172         s->nc.link_down = true;
 173         memset(s->buf, 0, sizeof(s->buf));
 174         memset(s->nc.info_str, 0, sizeof(s->nc.info_str));
 175
 176         return;
 177     }
 178     buf = buf1;
 179     while (size > 0) {
 180         /* reassemble a packet from the network */
 181         switch(s->state) {
 182         case 0:
 183             l = 4 - s->index;
 184             if (l > size)
 185                 l = size;
 186             memcpy(s->buf + s->index, buf, l);
 187             buf += l;
 188             size -= l;
 189             s->index += l;
 190             if (s->index == 4) {
 191                 /* got length */
 192                 s->packet_len = ntohl(*(uint32_t *)s->buf);
 193                 s->index = 0;
 194                 s->state = 1;
 195             }
 196             break;
 197         case 1:
 198             l = s->packet_len - s->index;
 199             if (l > size)
 200                 l = size;
 201             if (s->index + l <= sizeof(s->buf)) {
 202                 memcpy(s->buf + s->index, buf, l);
 203             } else {
 204                 fprintf(stderr, "serious error: oversized packet received,"
 205                     "connection terminated.\n");
 206                 s->state = 0;
 207                 goto eoc;
 208             }
 209
 210             s->index += l;
 211             buf += l;
 212             size -= l;
 213             if (s->index >= s->packet_len) {
 214                 qemu_send_packet(&s->nc, s->buf, s->packet_len);
 215                 s->index = 0;
 216                 s->state = 0;
 217             }
 218             break;
 219         }
 220     }
 221 }
 222
 223 static void net_socket_send_dgram(void *opaque)
 224 {
 225     NetSocketState *s = opaque;
 226     int size;
 227
 228     size = qemu_recv(s->fd, s->buf, sizeof(s->buf), 0);
 229     if (size < 0)
 230         return;
 231     if (size == 0) {
 232         /* end of connection */
 233         net_socket_read_poll(s, false);
 234         net_socket_write_poll(s, false);
 235         return;
 236     }
 237     qemu_send_packet(&s->nc, s->buf, size);
 238 }
 239
 240 static int net_socket_mcast_create(struct sockaddr_in *mcastaddr, struct in_addr *localaddr)
 241 {
 242     struct ip_mreq imr;
 243     int fd;
 244     int val, ret;
 245 #ifdef __OpenBSD__
 246     unsigned char loop;
 247 #else
 248     int loop;
 249 #endif
 250
 251     if (!IN_MULTICAST(ntohl(mcastaddr->sin_addr.s_addr))) {
 252         fprintf(stderr, "qemu: error: specified mcastaddr \"%s\" (0x%08x) "
 253                 "does not contain a multicast address\n",
 254                 inet_ntoa(mcastaddr->sin_addr),
 255                 (int)ntohl(mcastaddr->sin_addr.s_addr));
 256         return -1;
 257
 258     }
 259     fd = qemu_socket(PF_INET, SOCK_DGRAM, 0);
 260     if (fd < 0) {
 261         perror("socket(PF_INET, SOCK_DGRAM)");
 262         return -1;
 263     }
 264
 265     val = 1;
 266     ret = qemu_setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
 267     if (ret < 0) {
 268         perror("setsockopt(SOL_SOCKET, SO_REUSEADDR)");
 269         goto fail;
 270     }
 271
 272     ret = bind(fd, (struct sockaddr *)mcastaddr, sizeof(*mcastaddr));
 273     if (ret < 0) {
 274         perror("bind");
 275         goto fail;
 276     }
 277
 278     /* Add host to multicast group */
 279     imr.imr_multiaddr = mcastaddr->sin_addr;
 280     if (localaddr) {
 281         imr.imr_interface = *localaddr;
 282     } else {
 283         imr.imr_interface.s_addr = htonl(INADDR_ANY);
 284     }
 285
 286     ret = qemu_setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
 287                           &imr, sizeof(struct ip_mreq));
 288     if (ret < 0) {
 289         perror("setsockopt(IP_ADD_MEMBERSHIP)");
 290         goto fail;
 291     }
 292
 293     /* Force mcast msgs to loopback (eg. several QEMUs in same host */
 294     loop = 1;
 295     ret = qemu_setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP,
 296                           &loop, sizeof(loop));
 297     if (ret < 0) {
 298         perror("setsockopt(SOL_IP, IP_MULTICAST_LOOP)");
 299         goto fail;
 300     }
 301
 302     /* If a bind address is given, only send packets from that address */
 303     if (localaddr != NULL) {
 304         ret = qemu_setsockopt(fd, IPPROTO_IP, IP_MULTICAST_IF,
 305                               localaddr, sizeof(*localaddr));
 306         if (ret < 0) {
 307             perror("setsockopt(IP_MULTICAST_IF)");
 308             goto fail;
 309         }
 310     }
 311
 312     qemu_set_nonblock(fd);
 313     return fd;
 314 fail:
 315     if (fd >= 0)
 316         closesocket(fd);
 317     return -1;
 318 }
 319
 320 static void net_socket_cleanup(NetClientState *nc)
 321 {
 322     NetSocketState *s = DO_UPCAST(NetSocketState, nc, nc);
 323     if (s->fd != -1) {
 324         net_socket_read_poll(s, false);
 325         net_socket_write_poll(s, false);
 326         close(s->fd);
 327         s->fd = -1;
 328     }
 329     if (s->listen_fd != -1) {
 330         qemu_set_fd_handler(s->listen_fd, NULL, NULL, NULL);
 331         closesocket(s->listen_fd);
 332         s->listen_fd = -1;
 333     }
 334 }
 335
 336 static NetClientInfo net_dgram_socket_info = {
 337     .type = NET_CLIENT_OPTIONS_KIND_SOCKET,
 338     .size = sizeof(NetSocketState),
 339     .receive = net_socket_receive_dgram,
 340     .cleanup = net_socket_cleanup,
 341 };
 342
 343 static NetSocketState *net_socket_fd_init_dgram(NetClientState *peer,
 344                                                 const char *model,
 345                                                 const char *name,
 346                                                 int fd, int is_connected)
 347 {
 348     struct sockaddr_in saddr;
 349     int newfd;
 350     socklen_t saddr_len;
 351     NetClientState *nc;
 352     NetSocketState *s;
 353
 354     /* fd passed: multicast: "learn" dgram_dst address from bound address and save it
 355      * Because this may be "shared" socket from a "master" process, datagrams would be recv()
 356      * by ONLY ONE process: we must "clone" this dgram socket --jjo
 357      */
 358
 359     if (is_connected) {
 360         if (getsockname(fd, (struct sockaddr *) &saddr, &saddr_len) == 0) {
 361             /* must be bound */
 362             if (saddr.sin_addr.s_addr == 0) {
 363                 fprintf(stderr, "qemu: error: init_dgram: fd=%d unbound, "
 364                         "cannot setup multicast dst addr\n", fd);
 365                 goto err;
 366             }
 367             /* clone dgram socket */
 368             newfd = net_socket_mcast_create(&saddr, NULL);
 369             if (newfd < 0) {
 370                 /* error already reported by net_socket_mcast_create() */
 371                 goto err;
 372             }
 373             /* clone newfd to fd, close newfd */
 374             dup2(newfd, fd);
 375             close(newfd);
 376
 377         } else {
 378             fprintf(stderr,
 379                     "qemu: error: init_dgram: fd=%d failed getsockname(): %s\n",
 380                     fd, strerror(errno));
 381             goto err;
 382         }
 383     }
 384
 385     nc = qemu_new_net_client(&net_dgram_socket_info, peer, model, name);
 386
 387     snprintf(nc->info_str, sizeof(nc->info_str),
 388             "socket: fd=%d (%s mcast=%s:%d)",
 389             fd, is_connected ? "cloned" : "",
 390             inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
 391
 392     s = DO_UPCAST(NetSocketState, nc, nc);
 393
 394     s->fd = fd;
 395     s->listen_fd = -1;
 396     s->send_fn = net_socket_send_dgram;
 397     net_socket_read_poll(s, true);
 398
 399     /* mcast: save bound address as dst */
 400     if (is_connected) {
 401         s->dgram_dst = saddr;
 402     }
 403
 404     return s;
 405
 406 err:
 407     closesocket(fd);
 408     return NULL;
 409 }
 410
 411 static void net_socket_connect(void *opaque)
 412 {
 413     NetSocketState *s = opaque;
 414     s->send_fn = net_socket_send;
 415     net_socket_read_poll(s, true);
 416 }
 417
 418 static NetClientInfo net_socket_info = {
 419     .type = NET_CLIENT_OPTIONS_KIND_SOCKET,
 420     .size = sizeof(NetSocketState),
 421     .receive = net_socket_receive,
 422     .cleanup = net_socket_cleanup,
 423 };
 424
 425 static NetSocketState *net_socket_fd_init_stream(NetClientState *peer,
 426                                                  const char *model,
 427                                                  const char *name,
 428                                                  int fd, int is_connected)
 429 {
 430     NetClientState *nc;
 431     NetSocketState *s;
 432
 433     nc = qemu_new_net_client(&net_socket_info, peer, model, name);
 434
 435     snprintf(nc->info_str, sizeof(nc->info_str), "socket: fd=%d", fd);
 436
 437     s = DO_UPCAST(NetSocketState, nc, nc);
 438
 439     s->fd = fd;
 440     s->listen_fd = -1;
 441
 442     /* Disable Nagle algorithm on TCP sockets to reduce latency */
 443     socket_set_nodelay(fd);
 444
 445     if (is_connected) {
 446         net_socket_connect(s);
 447     } else {
 448         qemu_set_fd_handler(s->fd, NULL, net_socket_connect, s);
 449     }
 450     return s;
 451 }
 452
 453 static NetSocketState *net_socket_fd_init(NetClientState *peer,
 454                                           const char *model, const char *name,
 455                                           int fd, int is_connected)
 456 {
 457     int so_type = -1, optlen=sizeof(so_type);
 458
 459     if(getsockopt(fd, SOL_SOCKET, SO_TYPE, (char *)&so_type,
 460         (socklen_t *)&optlen)< 0) {
 461         fprintf(stderr, "qemu: error: getsockopt(SO_TYPE) for fd=%d failed\n",
 462                 fd);
 463         closesocket(fd);
 464         return NULL;
 465     }
 466     switch(so_type) {
 467     case SOCK_DGRAM:
 468         return net_socket_fd_init_dgram(peer, model, name, fd, is_connected);
 469     case SOCK_STREAM:
 470         return net_socket_fd_init_stream(peer, model, name, fd, is_connected);
 471     default:
 472         /* who knows ... this could be a eg. a pty, do warn and continue as stream */
 473         fprintf(stderr, "qemu: warning: socket type=%d for fd=%d is not SOCK_DGRAM or SOCK_STREAM\n", so_type, fd);
 474         return net_socket_fd_init_stream(peer, model, name, fd, is_connected);
 475     }
 476     return NULL;
 477 }
 478
 479 static void net_socket_accept(void *opaque)
 480 {
 481     NetSocketState *s = opaque;
 482     struct sockaddr_in saddr;
 483     socklen_t len;
 484     int fd;
 485
 486     for(;;) {
 487         len = sizeof(saddr);
 488         fd = qemu_accept(s->listen_fd, (struct sockaddr *)&saddr, &len);
 489         if (fd < 0 && errno != EINTR) {
 490             return;
 491         } else if (fd >= 0) {
 492             qemu_set_fd_handler(s->listen_fd, NULL, NULL, NULL);
 493             break;
 494         }
 495     }
 496
 497     s->fd = fd;
 498     s->nc.link_down = false;
 499     net_socket_connect(s);
 500     snprintf(s->nc.info_str, sizeof(s->nc.info_str),
 501              "socket: connection from %s:%d",
 502              inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
 503 }
 504
 505 static int net_socket_listen_init(NetClientState *peer,
 506                                   const char *model,
 507                                   const char *name,
 508                                   const char *host_str)
 509 {
 510     NetClientState *nc;
 511     NetSocketState *s;
 512     struct sockaddr_in saddr;
 513     int fd, val, ret;
 514
 515     if (parse_host_port(&saddr, host_str) < 0)
 516         return -1;
 517
 518     fd = qemu_socket(PF_INET, SOCK_STREAM, 0);
 519     if (fd < 0) {
 520         perror("socket");
 521         return -1;
 522     }
 523     qemu_set_nonblock(fd);
 524
 525     /* allow fast reuse */
 526     val = 1;
 527     qemu_setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
 528
 529     ret = bind(fd, (struct sockaddr *)&saddr, sizeof(saddr));
 530     if (ret < 0) {
 531         perror("bind");
 532         closesocket(fd);
 533         return -1;
 534     }
 535     ret = listen(fd, 0);
 536     if (ret < 0) {
 537         perror("listen");
 538         closesocket(fd);
 539         return -1;
 540     }
 541
 542     nc = qemu_new_net_client(&net_socket_info, peer, model, name);
 543     s = DO_UPCAST(NetSocketState, nc, nc);
 544     s->fd = -1;
 545     s->listen_fd = fd;
 546     s->nc.link_down = true;
 547
 548     qemu_set_fd_handler(s->listen_fd, net_socket_accept, NULL, s);
 549     return 0;
 550 }
 551
 552 static int net_socket_connect_init(NetClientState *peer,
 553                                    const char *model,
 554                                    const char *name,
 555                                    const char *host_str)
 556 {
 557     NetSocketState *s;
 558     int fd, connected, ret, err;
 559     struct sockaddr_in saddr;
 560
 561     if (parse_host_port(&saddr, host_str) < 0)
 562         return -1;
 563
 564     fd = qemu_socket(PF_INET, SOCK_STREAM, 0);
 565     if (fd < 0) {
 566         perror("socket");
 567         return -1;
 568     }
 569     qemu_set_nonblock(fd);
 570
 571     connected = 0;
 572     for(;;) {
 573         ret = connect(fd, (struct sockaddr *)&saddr, sizeof(saddr));
 574         if (ret < 0) {
 575             err = socket_error();
 576             if (err == EINTR || err == EWOULDBLOCK) {
 577             } else if (err == EINPROGRESS) {
 578                 break;
 579 #ifdef _WIN32
 580             } else if (err == WSAEALREADY || err == WSAEINVAL) {
 581                 break;
 582 #endif
 583             } else {
 584                 perror("connect");
 585                 closesocket(fd);
 586                 return -1;
 587             }
 588         } else {
 589             connected = 1;
 590             break;
 591         }
 592     }
 593     s = net_socket_fd_init(peer, model, name, fd, connected);
 594     if (!s)
 595         return -1;
 596     snprintf(s->nc.info_str, sizeof(s->nc.info_str),
 597              "socket: connect to %s:%d",
 598              inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
 599     return 0;
 600 }
 601
 602 static int net_socket_mcast_init(NetClientState *peer,
 603                                  const char *model,
 604                                  const char *name,
 605                                  const char *host_str,
 606                                  const char *localaddr_str)
 607 {
 608     NetSocketState *s;
 609     int fd;
 610     struct sockaddr_in saddr;
 611     struct in_addr localaddr, *param_localaddr;
 612
 613     if (parse_host_port(&saddr, host_str) < 0)
 614         return -1;
 615
 616     if (localaddr_str != NULL) {
 617         if (inet_aton(localaddr_str, &localaddr) == 0)
 618             return -1;
 619         param_localaddr = &localaddr;
 620     } else {
 621         param_localaddr = NULL;
 622     }
 623
 624     fd = net_socket_mcast_create(&saddr, param_localaddr);
 625     if (fd < 0)
 626         return -1;
 627
 628     s = net_socket_fd_init(peer, model, name, fd, 0);
 629     if (!s)
 630         return -1;
 631
 632     s->dgram_dst = saddr;
 633
 634     snprintf(s->nc.info_str, sizeof(s->nc.info_str),
 635              "socket: mcast=%s:%d",
 636              inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
 637     return 0;
 638
 639 }
 640
 641 static int net_socket_udp_init(NetClientState *peer,
 642                                  const char *model,
 643                                  const char *name,
 644                                  const char *rhost,
 645                                  const char *lhost)
 646 {
 647     NetSocketState *s;
 648     int fd, val, ret;
 649     struct sockaddr_in laddr, raddr;
 650
 651     if (parse_host_port(&laddr, lhost) < 0) {
 652         return -1;
 653     }
 654
 655     if (parse_host_port(&raddr, rhost) < 0) {
 656         return -1;
 657     }
 658
 659     fd = qemu_socket(PF_INET, SOCK_DGRAM, 0);
 660     if (fd < 0) {
 661         perror("socket(PF_INET, SOCK_DGRAM)");
 662         return -1;
 663     }
 664     val = 1;
 665     ret = qemu_setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
 666                           &val, sizeof(val));
 667     if (ret < 0) {
 668         perror("setsockopt(SOL_SOCKET, SO_REUSEADDR)");
 669         closesocket(fd);
 670         return -1;
 671     }
 672     ret = bind(fd, (struct sockaddr *)&laddr, sizeof(laddr));
 673     if (ret < 0) {
 674         perror("bind");
 675         closesocket(fd);
 676         return -1;
 677     }
 678     qemu_set_nonblock(fd);
 679
 680     s = net_socket_fd_init(peer, model, name, fd, 0);
 681     if (!s) {
 682         return -1;
 683     }
 684
 685     s->dgram_dst = raddr;
 686
 687     snprintf(s->nc.info_str, sizeof(s->nc.info_str),
 688              "socket: udp=%s:%d",
 689              inet_ntoa(raddr.sin_addr), ntohs(raddr.sin_port));
 690     return 0;
 691 }
 692
 693 int net_init_socket(const NetClientOptions *opts, const char *name,
 694                     NetClientState *peer)
 695 {
 696     const NetdevSocketOptions *sock;
 697
 698     assert(opts->kind == NET_CLIENT_OPTIONS_KIND_SOCKET);
 699     sock = opts->socket;
 700
 701     if (sock->has_fd + sock->has_listen + sock->has_connect + sock->has_mcast +
 702         sock->has_udp != 1) {
 703         error_report("exactly one of fd=, listen=, connect=, mcast= or udp="
 704                      " is required");
 705         return -1;
 706     }
 707
 708     if (sock->has_localaddr && !sock->has_mcast && !sock->has_udp) {
 709         error_report("localaddr= is only valid with mcast= or udp=");
 710         return -1;
 711     }
 712
 713     if (sock->has_fd) {
 714         int fd;
 715
 716         fd = monitor_handle_fd_param(cur_mon, sock->fd);
 717         if (fd == -1) {
 718             return -1;
 719         }
 720         qemu_set_nonblock(fd);
 721         if (!net_socket_fd_init(peer, "socket", name, fd, 1)) {
 722             return -1;
 723         }
 724         return 0;
 725     }
 726
 727     if (sock->has_listen) {
 728         if (net_socket_listen_init(peer, "socket", name, sock->listen) == -1) {
 729             return -1;
 730         }
 731         return 0;
 732     }
 733
 734     if (sock->has_connect) {
 735         if (net_socket_connect_init(peer, "socket", name, sock->connect) ==
 736             -1) {
 737             return -1;
 738         }
 739         return 0;
 740     }
 741
 742     if (sock->has_mcast) {
 743         /* if sock->localaddr is missing, it has been initialized to "all bits
 744          * zero" */
 745         if (net_socket_mcast_init(peer, "socket", name, sock->mcast,
 746             sock->localaddr) == -1) {
 747             return -1;
 748         }
 749         return 0;
 750     }
 751
 752     assert(sock->has_udp);
 753     if (!sock->has_localaddr) {
 754         error_report("localaddr= is mandatory with udp=");
 755         return -1;
 756     }
 757     if (net_socket_udp_init(peer, "socket", name, sock->udp, sock->localaddr) ==
 758         -1) {
 759         return -1;
 760     }
 761     return 0;
 762 }