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