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