net/slirp.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 "net/slirp.h"
  25
  26 #include "config-host.h"
  27
  28 #ifndef _WIN32
  29 #include <pwd.h>
  30 #include <sys/wait.h>
  31 #endif
  32 #include "net.h"
  33 #include "monitor.h"
  34 #include "qemu_socket.h"
  35 #include "slirp/libslirp.h"
  36
  37 static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
  38 {
  39     const char *p, *p1;
  40     int len;
  41     p = *pp;
  42     p1 = strchr(p, sep);
  43     if (!p1)
  44         return -1;
  45     len = p1 - p;
  46     p1++;
  47     if (buf_size > 0) {
  48         if (len > buf_size - 1)
  49             len = buf_size - 1;
  50         memcpy(buf, p, len);
  51         buf[len] = '\0';
  52     }
  53     *pp = p1;
  54     return 0;
  55 }
  56
  57 /* slirp network adapter */
  58
  59 #define SLIRP_CFG_HOSTFWD 1
  60 #define SLIRP_CFG_LEGACY  2
  61
  62 struct slirp_config_str {
  63     struct slirp_config_str *next;
  64     int flags;
  65     char str[1024];
  66     int legacy_format;
  67 };
  68
  69 typedef struct SlirpState {
  70     VLANClientState nc;
  71     QTAILQ_ENTRY(SlirpState) entry;
  72     Slirp *slirp;
  73 #ifndef _WIN32
  74     char smb_dir[128];
  75 #endif
  76 } SlirpState;
  77
  78 static struct slirp_config_str *slirp_configs;
  79 const char *legacy_tftp_prefix;
  80 const char *legacy_bootp_filename;
  81 static QTAILQ_HEAD(slirp_stacks, SlirpState) slirp_stacks =
  82     QTAILQ_HEAD_INITIALIZER(slirp_stacks);
  83
  84 static int slirp_hostfwd(SlirpState *s, const char *redir_str,
  85                          int legacy_format);
  86 static int slirp_guestfwd(SlirpState *s, const char *config_str,
  87                           int legacy_format);
  88
  89 #ifndef _WIN32
  90 static const char *legacy_smb_export;
  91
  92 static int slirp_smb(SlirpState *s, const char *exported_dir,
  93                      struct in_addr vserver_addr);
  94 static void slirp_smb_cleanup(SlirpState *s);
  95 #else
  96 static inline void slirp_smb_cleanup(SlirpState *s) { }
  97 #endif
  98
  99 int slirp_can_output(void *opaque)
 100 {
 101     SlirpState *s = opaque;
 102
 103     return qemu_can_send_packet(&s->nc);
 104 }
 105
 106 void slirp_output(void *opaque, const uint8_t *pkt, int pkt_len)
 107 {
 108     SlirpState *s = opaque;
 109
 110     qemu_send_packet(&s->nc, pkt, pkt_len);
 111 }
 112
 113 static ssize_t net_slirp_receive(VLANClientState *nc, const uint8_t *buf, size_t size)
 114 {
 115     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
 116
 117     slirp_input(s->slirp, buf, size);
 118
 119     return size;
 120 }
 121
 122 static void net_slirp_cleanup(VLANClientState *nc)
 123 {
 124     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
 125
 126     slirp_cleanup(s->slirp);
 127     slirp_smb_cleanup(s);
 128     QTAILQ_REMOVE(&slirp_stacks, s, entry);
 129 }
 130
 131 static NetClientInfo net_slirp_info = {
 132     .type = NET_CLIENT_TYPE_USER,
 133     .size = sizeof(SlirpState),
 134     .receive = net_slirp_receive,
 135     .cleanup = net_slirp_cleanup,
 136 };
 137
 138 static int net_slirp_init(VLANState *vlan, const char *model,
 139                           const char *name, int restricted,
 140                           const char *vnetwork, const char *vhost,
 141                           const char *vhostname, const char *tftp_export,
 142                           const char *bootfile, const char *vdhcp_start,
 143                           const char *vnameserver, const char *smb_export,
 144                           const char *vsmbserver)
 145 {
 146     /* default settings according to historic slirp */
 147     struct in_addr net  = { .s_addr = htonl(0x0a000200) }; /* 10.0.2.0 */
 148     struct in_addr mask = { .s_addr = htonl(0xffffff00) }; /* 255.255.255.0 */
 149     struct in_addr host = { .s_addr = htonl(0x0a000202) }; /* 10.0.2.2 */
 150     struct in_addr dhcp = { .s_addr = htonl(0x0a00020f) }; /* 10.0.2.15 */
 151     struct in_addr dns  = { .s_addr = htonl(0x0a000203) }; /* 10.0.2.3 */
 152 #ifndef _WIN32
 153     struct in_addr smbsrv = { .s_addr = 0 };
 154 #endif
 155     VLANClientState *nc;
 156     SlirpState *s;
 157     char buf[20];
 158     uint32_t addr;
 159     int shift;
 160     char *end;
 161     struct slirp_config_str *config;
 162
 163     if (!tftp_export) {
 164         tftp_export = legacy_tftp_prefix;
 165     }
 166     if (!bootfile) {
 167         bootfile = legacy_bootp_filename;
 168     }
 169
 170     if (vnetwork) {
 171         if (get_str_sep(buf, sizeof(buf), &vnetwork, '/') < 0) {
 172             if (!inet_aton(vnetwork, &net)) {
 173                 return -1;
 174             }
 175             addr = ntohl(net.s_addr);
 176             if (!(addr & 0x80000000)) {
 177                 mask.s_addr = htonl(0xff000000); /* class A */
 178             } else if ((addr & 0xfff00000) == 0xac100000) {
 179                 mask.s_addr = htonl(0xfff00000); /* priv. 172.16.0.0/12 */
 180             } else if ((addr & 0xc0000000) == 0x80000000) {
 181                 mask.s_addr = htonl(0xffff0000); /* class B */
 182             } else if ((addr & 0xffff0000) == 0xc0a80000) {
 183                 mask.s_addr = htonl(0xffff0000); /* priv. 192.168.0.0/16 */
 184             } else if ((addr & 0xffff0000) == 0xc6120000) {
 185                 mask.s_addr = htonl(0xfffe0000); /* tests 198.18.0.0/15 */
 186             } else if ((addr & 0xe0000000) == 0xe0000000) {
 187                 mask.s_addr = htonl(0xffffff00); /* class C */
 188             } else {
 189                 mask.s_addr = htonl(0xfffffff0); /* multicast/reserved */
 190             }
 191         } else {
 192             if (!inet_aton(buf, &net)) {
 193                 return -1;
 194             }
 195             shift = strtol(vnetwork, &end, 10);
 196             if (*end != '\0') {
 197                 if (!inet_aton(vnetwork, &mask)) {
 198                     return -1;
 199                 }
 200             } else if (shift < 4 || shift > 32) {
 201                 return -1;
 202             } else {
 203                 mask.s_addr = htonl(0xffffffff << (32 - shift));
 204             }
 205         }
 206         net.s_addr &= mask.s_addr;
 207         host.s_addr = net.s_addr | (htonl(0x0202) & ~mask.s_addr);
 208         dhcp.s_addr = net.s_addr | (htonl(0x020f) & ~mask.s_addr);
 209         dns.s_addr  = net.s_addr | (htonl(0x0203) & ~mask.s_addr);
 210     }
 211
 212     if (vhost && !inet_aton(vhost, &host)) {
 213         return -1;
 214     }
 215     if ((host.s_addr & mask.s_addr) != net.s_addr) {
 216         return -1;
 217     }
 218
 219     if (vdhcp_start && !inet_aton(vdhcp_start, &dhcp)) {
 220         return -1;
 221     }
 222     if ((dhcp.s_addr & mask.s_addr) != net.s_addr ||
 223         dhcp.s_addr == host.s_addr || dhcp.s_addr == dns.s_addr) {
 224         return -1;
 225     }
 226
 227     if (vnameserver && !inet_aton(vnameserver, &dns)) {
 228         return -1;
 229     }
 230     if ((dns.s_addr & mask.s_addr) != net.s_addr ||
 231         dns.s_addr == host.s_addr) {
 232         return -1;
 233     }
 234
 235 #ifndef _WIN32
 236     if (vsmbserver && !inet_aton(vsmbserver, &smbsrv)) {
 237         return -1;
 238     }
 239 #endif
 240
 241     nc = qemu_new_net_client(&net_slirp_info, vlan, NULL, model, name);
 242
 243     snprintf(nc->info_str, sizeof(nc->info_str),
 244              "net=%s,restrict=%s", inet_ntoa(net),
 245              restricted ? "on" : "off");
 246
 247     s = DO_UPCAST(SlirpState, nc, nc);
 248
 249     s->slirp = slirp_init(restricted, net, mask, host, vhostname,
 250                           tftp_export, bootfile, dhcp, dns, s);
 251     QTAILQ_INSERT_TAIL(&slirp_stacks, s, entry);
 252
 253     for (config = slirp_configs; config; config = config->next) {
 254         if (config->flags & SLIRP_CFG_HOSTFWD) {
 255             if (slirp_hostfwd(s, config->str,
 256                               config->flags & SLIRP_CFG_LEGACY) < 0)
 257                 goto error;
 258         } else {
 259             if (slirp_guestfwd(s, config->str,
 260                                config->flags & SLIRP_CFG_LEGACY) < 0)
 261                 goto error;
 262         }
 263     }
 264 #ifndef _WIN32
 265     if (!smb_export) {
 266         smb_export = legacy_smb_export;
 267     }
 268     if (smb_export) {
 269         if (slirp_smb(s, smb_export, smbsrv) < 0)
 270             goto error;
 271     }
 272 #endif
 273
 274     return 0;
 275
 276 error:
 277     qemu_del_vlan_client(nc);
 278     return -1;
 279 }
 280
 281 static SlirpState *slirp_lookup(Monitor *mon, const char *vlan,
 282                                 const char *stack)
 283 {
 284
 285     if (vlan) {
 286         VLANClientState *nc;
 287         nc = qemu_find_vlan_client_by_name(mon, strtol(vlan, NULL, 0), stack);
 288         if (!nc) {
 289             return NULL;
 290         }
 291         if (strcmp(nc->model, "user")) {
 292             monitor_printf(mon, "invalid device specified\n");
 293             return NULL;
 294         }
 295         return DO_UPCAST(SlirpState, nc, nc);
 296     } else {
 297         if (QTAILQ_EMPTY(&slirp_stacks)) {
 298             monitor_printf(mon, "user mode network stack not in use\n");
 299             return NULL;
 300         }
 301         return QTAILQ_FIRST(&slirp_stacks);
 302     }
 303 }
 304
 305 void net_slirp_hostfwd_remove(Monitor *mon, const QDict *qdict)
 306 {
 307     struct in_addr host_addr = { .s_addr = INADDR_ANY };
 308     int host_port;
 309     char buf[256];
 310     const char *src_str, *p;
 311     SlirpState *s;
 312     int is_udp = 0;
 313     int err;
 314     const char *arg1 = qdict_get_str(qdict, "arg1");
 315     const char *arg2 = qdict_get_try_str(qdict, "arg2");
 316     const char *arg3 = qdict_get_try_str(qdict, "arg3");
 317
 318     if (arg2) {
 319         s = slirp_lookup(mon, arg1, arg2);
 320         src_str = arg3;
 321     } else {
 322         s = slirp_lookup(mon, NULL, NULL);
 323         src_str = arg1;
 324     }
 325     if (!s) {
 326         return;
 327     }
 328
 329     p = src_str;
 330     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 331         goto fail_syntax;
 332     }
 333
 334     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
 335         is_udp = 0;
 336     } else if (!strcmp(buf, "udp")) {
 337         is_udp = 1;
 338     } else {
 339         goto fail_syntax;
 340     }
 341
 342     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 343         goto fail_syntax;
 344     }
 345     if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
 346         goto fail_syntax;
 347     }
 348
 349     host_port = atoi(p);
 350
 351     err = slirp_remove_hostfwd(QTAILQ_FIRST(&slirp_stacks)->slirp, is_udp,
 352                                host_addr, host_port);
 353
 354     monitor_printf(mon, "host forwarding rule for %s %s\n", src_str,
 355                    err ? "not found" : "removed");
 356     return;
 357
 358  fail_syntax:
 359     monitor_printf(mon, "invalid format\n");
 360 }
 361
 362 static int slirp_hostfwd(SlirpState *s, const char *redir_str,
 363                          int legacy_format)
 364 {
 365     struct in_addr host_addr = { .s_addr = INADDR_ANY };
 366     struct in_addr guest_addr = { .s_addr = 0 };
 367     int host_port, guest_port;
 368     const char *p;
 369     char buf[256];
 370     int is_udp;
 371     char *end;
 372
 373     p = redir_str;
 374     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 375         goto fail_syntax;
 376     }
 377     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
 378         is_udp = 0;
 379     } else if (!strcmp(buf, "udp")) {
 380         is_udp = 1;
 381     } else {
 382         goto fail_syntax;
 383     }
 384
 385     if (!legacy_format) {
 386         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 387             goto fail_syntax;
 388         }
 389         if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
 390             goto fail_syntax;
 391         }
 392     }
 393
 394     if (get_str_sep(buf, sizeof(buf), &p, legacy_format ? ':' : '-') < 0) {
 395         goto fail_syntax;
 396     }
 397     host_port = strtol(buf, &end, 0);
 398     if (*end != '\0' || host_port < 1 || host_port > 65535) {
 399         goto fail_syntax;
 400     }
 401
 402     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 403         goto fail_syntax;
 404     }
 405     if (buf[0] != '\0' && !inet_aton(buf, &guest_addr)) {
 406         goto fail_syntax;
 407     }
 408
 409     guest_port = strtol(p, &end, 0);
 410     if (*end != '\0' || guest_port < 1 || guest_port > 65535) {
 411         goto fail_syntax;
 412     }
 413
 414     if (slirp_add_hostfwd(s->slirp, is_udp, host_addr, host_port, guest_addr,
 415                           guest_port) < 0) {
 416         error_report("could not set up host forwarding rule '%s'",
 417                      redir_str);
 418         return -1;
 419     }
 420     return 0;
 421
 422  fail_syntax:
 423     error_report("invalid host forwarding rule '%s'", redir_str);
 424     return -1;
 425 }
 426
 427 void net_slirp_hostfwd_add(Monitor *mon, const QDict *qdict)
 428 {
 429     const char *redir_str;
 430     SlirpState *s;
 431     const char *arg1 = qdict_get_str(qdict, "arg1");
 432     const char *arg2 = qdict_get_try_str(qdict, "arg2");
 433     const char *arg3 = qdict_get_try_str(qdict, "arg3");
 434
 435     if (arg2) {
 436         s = slirp_lookup(mon, arg1, arg2);
 437         redir_str = arg3;
 438     } else {
 439         s = slirp_lookup(mon, NULL, NULL);
 440         redir_str = arg1;
 441     }
 442     if (s) {
 443         slirp_hostfwd(s, redir_str, 0);
 444     }
 445
 446 }
 447
 448 int net_slirp_redir(const char *redir_str)
 449 {
 450     struct slirp_config_str *config;
 451
 452     if (QTAILQ_EMPTY(&slirp_stacks)) {
 453         config = g_malloc(sizeof(*config));
 454         pstrcpy(config->str, sizeof(config->str), redir_str);
 455         config->flags = SLIRP_CFG_HOSTFWD | SLIRP_CFG_LEGACY;
 456         config->next = slirp_configs;
 457         slirp_configs = config;
 458         return 0;
 459     }
 460
 461     return slirp_hostfwd(QTAILQ_FIRST(&slirp_stacks), redir_str, 1);
 462 }
 463
 464 #ifndef _WIN32
 465
 466 /* automatic user mode samba server configuration */
 467 static void slirp_smb_cleanup(SlirpState *s)
 468 {
 469     char cmd[128];
 470     int ret;
 471
 472     if (s->smb_dir[0] != '\0') {
 473         snprintf(cmd, sizeof(cmd), "rm -rf %s", s->smb_dir);
 474         ret = system(cmd);
 475         if (ret == -1 || !WIFEXITED(ret)) {
 476             error_report("'%s' failed.", cmd);
 477         } else if (WEXITSTATUS(ret)) {
 478             error_report("'%s' failed. Error code: %d",
 479                          cmd, WEXITSTATUS(ret));
 480         }
 481         s->smb_dir[0] = '\0';
 482     }
 483 }
 484
 485 static int slirp_smb(SlirpState* s, const char *exported_dir,
 486                      struct in_addr vserver_addr)
 487 {
 488     static int instance;
 489     char smb_conf[128];
 490     char smb_cmdline[128];
 491     struct passwd *passwd;
 492     FILE *f;
 493
 494     passwd = getpwuid(geteuid());
 495     if (!passwd) {
 496         error_report("failed to retrieve user name");
 497         return -1;
 498     }
 499
 500     if (access(CONFIG_SMBD_COMMAND, F_OK)) {
 501         error_report("could not find '%s', please install it",
 502                      CONFIG_SMBD_COMMAND);
 503         return -1;
 504     }
 505
 506     if (access(exported_dir, R_OK | X_OK)) {
 507         error_report("error accessing shared directory '%s': %s",
 508                      exported_dir, strerror(errno));
 509         return -1;
 510     }
 511
 512     snprintf(s->smb_dir, sizeof(s->smb_dir), "/tmp/qemu-smb.%ld-%d",
 513              (long)getpid(), instance++);
 514     if (mkdir(s->smb_dir, 0700) < 0) {
 515         error_report("could not create samba server dir '%s'", s->smb_dir);
 516         return -1;
 517     }
 518     snprintf(smb_conf, sizeof(smb_conf), "%s/%s", s->smb_dir, "smb.conf");
 519
 520     f = fopen(smb_conf, "w");
 521     if (!f) {
 522         slirp_smb_cleanup(s);
 523         error_report("could not create samba server configuration file '%s'",
 524                      smb_conf);
 525         return -1;
 526     }
 527     fprintf(f,
 528             "[global]\n"
 529             "private dir=%s\n"
 530             "socket address=127.0.0.1\n"
 531             "pid directory=%s\n"
 532             "lock directory=%s\n"
 533             "state directory=%s\n"
 534             "log file=%s/log.smbd\n"
 535             "smb passwd file=%s/smbpasswd\n"
 536             "security = share\n"
 537             "[qemu]\n"
 538             "path=%s\n"
 539             "read only=no\n"
 540             "guest ok=yes\n"
 541             "force user=%s\n",
 542             s->smb_dir,
 543             s->smb_dir,
 544             s->smb_dir,
 545             s->smb_dir,
 546             s->smb_dir,
 547             s->smb_dir,
 548             exported_dir,
 549             passwd->pw_name
 550             );
 551     fclose(f);
 552
 553     snprintf(smb_cmdline, sizeof(smb_cmdline), "%s -s %s",
 554              CONFIG_SMBD_COMMAND, smb_conf);
 555
 556     if (slirp_add_exec(s->slirp, 0, smb_cmdline, &vserver_addr, 139) < 0) {
 557         slirp_smb_cleanup(s);
 558         error_report("conflicting/invalid smbserver address");
 559         return -1;
 560     }
 561     return 0;
 562 }
 563
 564 /* automatic user mode samba server configuration (legacy interface) */
 565 int net_slirp_smb(const char *exported_dir)
 566 {
 567     struct in_addr vserver_addr = { .s_addr = 0 };
 568
 569     if (legacy_smb_export) {
 570         fprintf(stderr, "-smb given twice\n");
 571         return -1;
 572     }
 573     legacy_smb_export = exported_dir;
 574     if (!QTAILQ_EMPTY(&slirp_stacks)) {
 575         return slirp_smb(QTAILQ_FIRST(&slirp_stacks), exported_dir,
 576                          vserver_addr);
 577     }
 578     return 0;
 579 }
 580
 581 #endif /* !defined(_WIN32) */
 582
 583 struct GuestFwd {
 584     CharDriverState *hd;
 585     struct in_addr server;
 586     int port;
 587     Slirp *slirp;
 588 };
 589
 590 static int guestfwd_can_read(void *opaque)
 591 {
 592     struct GuestFwd *fwd = opaque;
 593     return slirp_socket_can_recv(fwd->slirp, fwd->server, fwd->port);
 594 }
 595
 596 static void guestfwd_read(void *opaque, const uint8_t *buf, int size)
 597 {
 598     struct GuestFwd *fwd = opaque;
 599     slirp_socket_recv(fwd->slirp, fwd->server, fwd->port, buf, size);
 600 }
 601
 602 static int slirp_guestfwd(SlirpState *s, const char *config_str,
 603                           int legacy_format)
 604 {
 605     struct in_addr server = { .s_addr = 0 };
 606     struct GuestFwd *fwd;
 607     const char *p;
 608     char buf[128];
 609     char *end;
 610     int port;
 611
 612     p = config_str;
 613     if (legacy_format) {
 614         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 615             goto fail_syntax;
 616         }
 617     } else {
 618         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 619             goto fail_syntax;
 620         }
 621         if (strcmp(buf, "tcp") && buf[0] != '\0') {
 622             goto fail_syntax;
 623         }
 624         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 625             goto fail_syntax;
 626         }
 627         if (buf[0] != '\0' && !inet_aton(buf, &server)) {
 628             goto fail_syntax;
 629         }
 630         if (get_str_sep(buf, sizeof(buf), &p, '-') < 0) {
 631             goto fail_syntax;
 632         }
 633     }
 634     port = strtol(buf, &end, 10);
 635     if (*end != '\0' || port < 1 || port > 65535) {
 636         goto fail_syntax;
 637     }
 638
 639     fwd = g_malloc(sizeof(struct GuestFwd));
 640     snprintf(buf, sizeof(buf), "guestfwd.tcp.%d", port);
 641
 642     if ((strlen(p) > 4) && !strncmp(p, "cmd:", 4)) {
 643         if (slirp_add_exec(s->slirp, 0, &p[4], &server, port) < 0) {
 644             error_report("conflicting/invalid host:port in guest forwarding "
 645                          "rule '%s'", config_str);
 646             g_free(fwd);
 647             return -1;
 648         }
 649     } else {
 650         fwd->hd = qemu_chr_new(buf, p, NULL);
 651         if (!fwd->hd) {
 652             error_report("could not open guest forwarding device '%s'", buf);
 653             g_free(fwd);
 654             return -1;
 655         }
 656
 657         if (slirp_add_exec(s->slirp, 3, fwd->hd, &server, port) < 0) {
 658             error_report("conflicting/invalid host:port in guest forwarding "
 659                          "rule '%s'", config_str);
 660             g_free(fwd);
 661             return -1;
 662         }
 663         fwd->server = server;
 664         fwd->port = port;
 665         fwd->slirp = s->slirp;
 666
 667         qemu_chr_add_handlers(fwd->hd, guestfwd_can_read, guestfwd_read,
 668                               NULL, fwd);
 669     }
 670     return 0;
 671
 672  fail_syntax:
 673     error_report("invalid guest forwarding rule '%s'", config_str);
 674     return -1;
 675 }
 676
 677 void do_info_usernet(Monitor *mon)
 678 {
 679     SlirpState *s;
 680
 681     QTAILQ_FOREACH(s, &slirp_stacks, entry) {
 682         monitor_printf(mon, "VLAN %d (%s):\n",
 683                        s->nc.vlan ? s->nc.vlan->id : -1,
 684                        s->nc.name);
 685         slirp_connection_info(s->slirp, mon);
 686     }
 687 }
 688
 689 static int net_init_slirp_configs(const char *name, const char *value, void *opaque)
 690 {
 691     struct slirp_config_str *config;
 692
 693     if (strcmp(name, "hostfwd") != 0 && strcmp(name, "guestfwd") != 0) {
 694         return 0;
 695     }
 696
 697     config = g_malloc0(sizeof(*config));
 698
 699     pstrcpy(config->str, sizeof(config->str), value);
 700
 701     if (!strcmp(name, "hostfwd")) {
 702         config->flags = SLIRP_CFG_HOSTFWD;
 703     }
 704
 705     config->next = slirp_configs;
 706     slirp_configs = config;
 707
 708     return 0;
 709 }
 710
 711 int net_init_slirp(QemuOpts *opts, const char *name, VLANState *vlan)
 712 {
 713     struct slirp_config_str *config;
 714     const char *vhost;
 715     const char *vhostname;
 716     const char *vdhcp_start;
 717     const char *vnamesrv;
 718     const char *tftp_export;
 719     const char *bootfile;
 720     const char *smb_export;
 721     const char *vsmbsrv;
 722     const char *restrict_opt;
 723     char *vnet = NULL;
 724     int restricted = 0;
 725     int ret;
 726
 727     vhost       = qemu_opt_get(opts, "host");
 728     vhostname   = qemu_opt_get(opts, "hostname");
 729     vdhcp_start = qemu_opt_get(opts, "dhcpstart");
 730     vnamesrv    = qemu_opt_get(opts, "dns");
 731     tftp_export = qemu_opt_get(opts, "tftp");
 732     bootfile    = qemu_opt_get(opts, "bootfile");
 733     smb_export  = qemu_opt_get(opts, "smb");
 734     vsmbsrv     = qemu_opt_get(opts, "smbserver");
 735
 736     restrict_opt = qemu_opt_get(opts, "restrict");
 737     if (restrict_opt) {
 738         if (!strcmp(restrict_opt, "on") ||
 739             !strcmp(restrict_opt, "yes") || !strcmp(restrict_opt, "y")) {
 740             restricted = 1;
 741         } else if (strcmp(restrict_opt, "off") &&
 742             strcmp(restrict_opt, "no") && strcmp(restrict_opt, "n")) {
 743             error_report("invalid option: 'restrict=%s'", restrict_opt);
 744             return -1;
 745         }
 746     }
 747
 748     if (qemu_opt_get(opts, "ip")) {
 749         const char *ip = qemu_opt_get(opts, "ip");
 750         int l = strlen(ip) + strlen("/24") + 1;
 751
 752         vnet = g_malloc(l);
 753
 754         /* emulate legacy ip= parameter */
 755         pstrcpy(vnet, l, ip);
 756         pstrcat(vnet, l, "/24");
 757     }
 758
 759     if (qemu_opt_get(opts, "net")) {
 760         if (vnet) {
 761             g_free(vnet);
 762         }
 763         vnet = g_strdup(qemu_opt_get(opts, "net"));
 764     }
 765
 766     qemu_opt_foreach(opts, net_init_slirp_configs, NULL, 0);
 767
 768     ret = net_slirp_init(vlan, "user", name, restricted, vnet, vhost,
 769                          vhostname, tftp_export, bootfile, vdhcp_start,
 770                          vnamesrv, smb_export, vsmbsrv);
 771
 772     while (slirp_configs) {
 773         config = slirp_configs;
 774         slirp_configs = config->next;
 775         g_free(config);
 776     }
 777
 778     g_free(vnet);
 779
 780     return ret;
 781 }
 782
 783 int net_slirp_parse_legacy(QemuOptsList *opts_list, const char *optarg, int *ret)
 784 {
 785     if (strcmp(opts_list->name, "net") != 0 ||
 786         strncmp(optarg, "channel,", strlen("channel,")) != 0) {
 787         return 0;
 788     }
 789
 790     /* handle legacy -net channel,port:chr */
 791     optarg += strlen("channel,");
 792
 793     if (QTAILQ_EMPTY(&slirp_stacks)) {
 794         struct slirp_config_str *config;
 795
 796         config = g_malloc(sizeof(*config));
 797         pstrcpy(config->str, sizeof(config->str), optarg);
 798         config->flags = SLIRP_CFG_LEGACY;
 799         config->next = slirp_configs;
 800         slirp_configs = config;
 801         *ret = 0;
 802     } else {
 803         *ret = slirp_guestfwd(QTAILQ_FIRST(&slirp_stacks), optarg, 1);
 804     }
 805
 806     return 1;
 807 }
 808