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 "qemu/osdep.h"
  25 #include "net/slirp.h"
  26
  27
  28 #ifndef _WIN32
  29 #include <pwd.h>
  30 #include <sys/wait.h>
  31 #endif
  32 #include "net/net.h"
  33 #include "clients.h"
  34 #include "hub.h"
  35 #include "monitor/monitor.h"
  36 #include "qemu/error-report.h"
  37 #include "qemu/sockets.h"
  38 #include "slirp/libslirp.h"
  39 #include "slirp/ip6.h"
  40 #include "sysemu/char.h"
  41
  42 static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
  43 {
  44     const char *p, *p1;
  45     int len;
  46     p = *pp;
  47     p1 = strchr(p, sep);
  48     if (!p1)
  49         return -1;
  50     len = p1 - p;
  51     p1++;
  52     if (buf_size > 0) {
  53         if (len > buf_size - 1)
  54             len = buf_size - 1;
  55         memcpy(buf, p, len);
  56         buf[len] = '\0';
  57     }
  58     *pp = p1;
  59     return 0;
  60 }
  61
  62 /* slirp network adapter */
  63
  64 #define SLIRP_CFG_HOSTFWD 1
  65 #define SLIRP_CFG_LEGACY  2
  66
  67 struct slirp_config_str {
  68     struct slirp_config_str *next;
  69     int flags;
  70     char str[1024];
  71     int legacy_format;
  72 };
  73
  74 typedef struct SlirpState {
  75     NetClientState nc;
  76     QTAILQ_ENTRY(SlirpState) entry;
  77     Slirp *slirp;
  78 #ifndef _WIN32
  79     char smb_dir[128];
  80 #endif
  81 } SlirpState;
  82
  83 static struct slirp_config_str *slirp_configs;
  84 const char *legacy_tftp_prefix;
  85 const char *legacy_bootp_filename;
  86 static QTAILQ_HEAD(slirp_stacks, SlirpState) slirp_stacks =
  87     QTAILQ_HEAD_INITIALIZER(slirp_stacks);
  88
  89 static int slirp_hostfwd(SlirpState *s, const char *redir_str,
  90                          int legacy_format);
  91 static int slirp_guestfwd(SlirpState *s, const char *config_str,
  92                           int legacy_format);
  93
  94 #ifndef _WIN32
  95 static const char *legacy_smb_export;
  96
  97 static int slirp_smb(SlirpState *s, const char *exported_dir,
  98                      struct in_addr vserver_addr);
  99 static void slirp_smb_cleanup(SlirpState *s);
 100 #else
 101 static inline void slirp_smb_cleanup(SlirpState *s) { }
 102 #endif
 103
 104 void slirp_output(void *opaque, const uint8_t *pkt, int pkt_len)
 105 {
 106     SlirpState *s = opaque;
 107
 108     qemu_send_packet(&s->nc, pkt, pkt_len);
 109 }
 110
 111 static ssize_t net_slirp_receive(NetClientState *nc, const uint8_t *buf, size_t size)
 112 {
 113     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
 114
 115     slirp_input(s->slirp, buf, size);
 116
 117     return size;
 118 }
 119
 120 static void net_slirp_cleanup(NetClientState *nc)
 121 {
 122     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
 123
 124     slirp_cleanup(s->slirp);
 125     slirp_smb_cleanup(s);
 126     QTAILQ_REMOVE(&slirp_stacks, s, entry);
 127 }
 128
 129 static NetClientInfo net_slirp_info = {
 130     .type = NET_CLIENT_OPTIONS_KIND_USER,
 131     .size = sizeof(SlirpState),
 132     .receive = net_slirp_receive,
 133     .cleanup = net_slirp_cleanup,
 134 };
 135
 136 static int net_slirp_init(NetClientState *peer, const char *model,
 137                           const char *name, int restricted,
 138                           const char *vnetwork, const char *vhost,
 139                           const char *vprefix6, int vprefix6_len,
 140                           const char *vhost6,
 141                           const char *vhostname, const char *tftp_export,
 142                           const char *bootfile, const char *vdhcp_start,
 143                           const char *vnameserver, const char *vnameserver6,
 144                           const char *smb_export, const char *vsmbserver,
 145                           const char **dnssearch)
 146 {
 147     /* default settings according to historic slirp */
 148     struct in_addr net  = { .s_addr = htonl(0x0a000200) }; /* 10.0.2.0 */
 149     struct in_addr mask = { .s_addr = htonl(0xffffff00) }; /* 255.255.255.0 */
 150     struct in_addr host = { .s_addr = htonl(0x0a000202) }; /* 10.0.2.2 */
 151     struct in_addr dhcp = { .s_addr = htonl(0x0a00020f) }; /* 10.0.2.15 */
 152     struct in_addr dns  = { .s_addr = htonl(0x0a000203) }; /* 10.0.2.3 */
 153     struct in6_addr ip6_prefix;
 154     struct in6_addr ip6_host;
 155     struct in6_addr ip6_dns;
 156 #ifndef _WIN32
 157     struct in_addr smbsrv = { .s_addr = 0 };
 158 #endif
 159     NetClientState *nc;
 160     SlirpState *s;
 161     char buf[20];
 162     uint32_t addr;
 163     int shift;
 164     char *end;
 165     struct slirp_config_str *config;
 166
 167     if (!tftp_export) {
 168         tftp_export = legacy_tftp_prefix;
 169     }
 170     if (!bootfile) {
 171         bootfile = legacy_bootp_filename;
 172     }
 173
 174     if (vnetwork) {
 175         if (get_str_sep(buf, sizeof(buf), &vnetwork, '/') < 0) {
 176             if (!inet_aton(vnetwork, &net)) {
 177                 return -1;
 178             }
 179             addr = ntohl(net.s_addr);
 180             if (!(addr & 0x80000000)) {
 181                 mask.s_addr = htonl(0xff000000); /* class A */
 182             } else if ((addr & 0xfff00000) == 0xac100000) {
 183                 mask.s_addr = htonl(0xfff00000); /* priv. 172.16.0.0/12 */
 184             } else if ((addr & 0xc0000000) == 0x80000000) {
 185                 mask.s_addr = htonl(0xffff0000); /* class B */
 186             } else if ((addr & 0xffff0000) == 0xc0a80000) {
 187                 mask.s_addr = htonl(0xffff0000); /* priv. 192.168.0.0/16 */
 188             } else if ((addr & 0xffff0000) == 0xc6120000) {
 189                 mask.s_addr = htonl(0xfffe0000); /* tests 198.18.0.0/15 */
 190             } else if ((addr & 0xe0000000) == 0xe0000000) {
 191                 mask.s_addr = htonl(0xffffff00); /* class C */
 192             } else {
 193                 mask.s_addr = htonl(0xfffffff0); /* multicast/reserved */
 194             }
 195         } else {
 196             if (!inet_aton(buf, &net)) {
 197                 return -1;
 198             }
 199             shift = strtol(vnetwork, &end, 10);
 200             if (*end != '\0') {
 201                 if (!inet_aton(vnetwork, &mask)) {
 202                     return -1;
 203                 }
 204             } else if (shift < 4 || shift > 32) {
 205                 return -1;
 206             } else {
 207                 mask.s_addr = htonl(0xffffffff << (32 - shift));
 208             }
 209         }
 210         net.s_addr &= mask.s_addr;
 211         host.s_addr = net.s_addr | (htonl(0x0202) & ~mask.s_addr);
 212         dhcp.s_addr = net.s_addr | (htonl(0x020f) & ~mask.s_addr);
 213         dns.s_addr  = net.s_addr | (htonl(0x0203) & ~mask.s_addr);
 214     }
 215
 216     if (vhost && !inet_aton(vhost, &host)) {
 217         return -1;
 218     }
 219     if ((host.s_addr & mask.s_addr) != net.s_addr) {
 220         return -1;
 221     }
 222
 223     if (vnameserver && !inet_aton(vnameserver, &dns)) {
 224         return -1;
 225     }
 226     if ((dns.s_addr & mask.s_addr) != net.s_addr ||
 227         dns.s_addr == host.s_addr) {
 228         return -1;
 229     }
 230
 231     if (vdhcp_start && !inet_aton(vdhcp_start, &dhcp)) {
 232         return -1;
 233     }
 234     if ((dhcp.s_addr & mask.s_addr) != net.s_addr ||
 235         dhcp.s_addr == host.s_addr || dhcp.s_addr == dns.s_addr) {
 236         return -1;
 237     }
 238
 239 #ifndef _WIN32
 240     if (vsmbserver && !inet_aton(vsmbserver, &smbsrv)) {
 241         return -1;
 242     }
 243 #endif
 244
 245 #if defined(_WIN32) && (_WIN32_WINNT < 0x0600)
 246     /* No inet_pton helper before Vista... */
 247     if (vprefix6) {
 248         /* Unsupported */
 249         return -1;
 250     }
 251     memset(&ip6_prefix, 0, sizeof(ip6_prefix));
 252     ip6_prefix.s6_addr[0] = 0xfe;
 253     ip6_prefix.s6_addr[1] = 0xc0;
 254 #else
 255     if (!vprefix6) {
 256         vprefix6 = "fec0::";
 257     }
 258     if (!inet_pton(AF_INET6, vprefix6, &ip6_prefix)) {
 259         return -1;
 260     }
 261 #endif
 262
 263     if (!vprefix6_len) {
 264         vprefix6_len = 64;
 265     }
 266     if (vprefix6_len < 0 || vprefix6_len > 126) {
 267         return -1;
 268     }
 269
 270     if (vhost6) {
 271 #if defined(_WIN32) && (_WIN32_WINNT < 0x0600)
 272         return -1;
 273 #else
 274         if (!inet_pton(AF_INET6, vhost6, &ip6_host)) {
 275             return -1;
 276         }
 277         if (!in6_equal_net(&ip6_prefix, &ip6_host, vprefix6_len)) {
 278             return -1;
 279         }
 280 #endif
 281     } else {
 282         ip6_host = ip6_prefix;
 283         ip6_host.s6_addr[15] |= 2;
 284     }
 285
 286     if (vnameserver6) {
 287 #if defined(_WIN32) && (_WIN32_WINNT < 0x0600)
 288         return -1;
 289 #else
 290         if (!inet_pton(AF_INET6, vnameserver6, &ip6_dns)) {
 291             return -1;
 292         }
 293         if (!in6_equal_net(&ip6_prefix, &ip6_dns, vprefix6_len)) {
 294             return -1;
 295         }
 296 #endif
 297     } else {
 298         ip6_dns = ip6_prefix;
 299         ip6_dns.s6_addr[15] |= 3;
 300     }
 301
 302
 303     nc = qemu_new_net_client(&net_slirp_info, peer, model, name);
 304
 305     snprintf(nc->info_str, sizeof(nc->info_str),
 306              "net=%s,restrict=%s", inet_ntoa(net),
 307              restricted ? "on" : "off");
 308
 309     s = DO_UPCAST(SlirpState, nc, nc);
 310
 311     s->slirp = slirp_init(restricted, net, mask, host,
 312                           ip6_prefix, vprefix6_len, ip6_host,
 313                           vhostname, tftp_export, bootfile, dhcp,
 314                           dns, ip6_dns, dnssearch, s);
 315     QTAILQ_INSERT_TAIL(&slirp_stacks, s, entry);
 316
 317     for (config = slirp_configs; config; config = config->next) {
 318         if (config->flags & SLIRP_CFG_HOSTFWD) {
 319             if (slirp_hostfwd(s, config->str,
 320                               config->flags & SLIRP_CFG_LEGACY) < 0)
 321                 goto error;
 322         } else {
 323             if (slirp_guestfwd(s, config->str,
 324                                config->flags & SLIRP_CFG_LEGACY) < 0)
 325                 goto error;
 326         }
 327     }
 328 #ifndef _WIN32
 329     if (!smb_export) {
 330         smb_export = legacy_smb_export;
 331     }
 332     if (smb_export) {
 333         if (slirp_smb(s, smb_export, smbsrv) < 0)
 334             goto error;
 335     }
 336 #endif
 337
 338     return 0;
 339
 340 error:
 341     qemu_del_net_client(nc);
 342     return -1;
 343 }
 344
 345 static SlirpState *slirp_lookup(Monitor *mon, const char *vlan,
 346                                 const char *stack)
 347 {
 348
 349     if (vlan) {
 350         NetClientState *nc;
 351         nc = net_hub_find_client_by_name(strtol(vlan, NULL, 0), stack);
 352         if (!nc) {
 353             monitor_printf(mon, "unrecognized (vlan-id, stackname) pair\n");
 354             return NULL;
 355         }
 356         if (strcmp(nc->model, "user")) {
 357             monitor_printf(mon, "invalid device specified\n");
 358             return NULL;
 359         }
 360         return DO_UPCAST(SlirpState, nc, nc);
 361     } else {
 362         if (QTAILQ_EMPTY(&slirp_stacks)) {
 363             monitor_printf(mon, "user mode network stack not in use\n");
 364             return NULL;
 365         }
 366         return QTAILQ_FIRST(&slirp_stacks);
 367     }
 368 }
 369
 370 void hmp_hostfwd_remove(Monitor *mon, const QDict *qdict)
 371 {
 372     struct in_addr host_addr = { .s_addr = INADDR_ANY };
 373     int host_port;
 374     char buf[256];
 375     const char *src_str, *p;
 376     SlirpState *s;
 377     int is_udp = 0;
 378     int err;
 379     const char *arg1 = qdict_get_str(qdict, "arg1");
 380     const char *arg2 = qdict_get_try_str(qdict, "arg2");
 381     const char *arg3 = qdict_get_try_str(qdict, "arg3");
 382
 383     if (arg2) {
 384         s = slirp_lookup(mon, arg1, arg2);
 385         src_str = arg3;
 386     } else {
 387         s = slirp_lookup(mon, NULL, NULL);
 388         src_str = arg1;
 389     }
 390     if (!s) {
 391         return;
 392     }
 393
 394     p = src_str;
 395     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 396         goto fail_syntax;
 397     }
 398
 399     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
 400         is_udp = 0;
 401     } else if (!strcmp(buf, "udp")) {
 402         is_udp = 1;
 403     } else {
 404         goto fail_syntax;
 405     }
 406
 407     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 408         goto fail_syntax;
 409     }
 410     if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
 411         goto fail_syntax;
 412     }
 413
 414     host_port = atoi(p);
 415
 416     err = slirp_remove_hostfwd(s->slirp, is_udp, host_addr, host_port);
 417
 418     monitor_printf(mon, "host forwarding rule for %s %s\n", src_str,
 419                    err ? "not found" : "removed");
 420     return;
 421
 422  fail_syntax:
 423     monitor_printf(mon, "invalid format\n");
 424 }
 425
 426 static int slirp_hostfwd(SlirpState *s, const char *redir_str,
 427                          int legacy_format)
 428 {
 429     struct in_addr host_addr = { .s_addr = INADDR_ANY };
 430     struct in_addr guest_addr = { .s_addr = 0 };
 431     int host_port, guest_port;
 432     const char *p;
 433     char buf[256];
 434     int is_udp;
 435     char *end;
 436
 437     p = redir_str;
 438     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 439         goto fail_syntax;
 440     }
 441     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
 442         is_udp = 0;
 443     } else if (!strcmp(buf, "udp")) {
 444         is_udp = 1;
 445     } else {
 446         goto fail_syntax;
 447     }
 448
 449     if (!legacy_format) {
 450         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 451             goto fail_syntax;
 452         }
 453         if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
 454             goto fail_syntax;
 455         }
 456     }
 457
 458     if (get_str_sep(buf, sizeof(buf), &p, legacy_format ? ':' : '-') < 0) {
 459         goto fail_syntax;
 460     }
 461     host_port = strtol(buf, &end, 0);
 462     if (*end != '\0' || host_port < 1 || host_port > 65535) {
 463         goto fail_syntax;
 464     }
 465
 466     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 467         goto fail_syntax;
 468     }
 469     if (buf[0] != '\0' && !inet_aton(buf, &guest_addr)) {
 470         goto fail_syntax;
 471     }
 472
 473     guest_port = strtol(p, &end, 0);
 474     if (*end != '\0' || guest_port < 1 || guest_port > 65535) {
 475         goto fail_syntax;
 476     }
 477
 478     if (slirp_add_hostfwd(s->slirp, is_udp, host_addr, host_port, guest_addr,
 479                           guest_port) < 0) {
 480         error_report("could not set up host forwarding rule '%s'",
 481                      redir_str);
 482         return -1;
 483     }
 484     return 0;
 485
 486  fail_syntax:
 487     error_report("invalid host forwarding rule '%s'", redir_str);
 488     return -1;
 489 }
 490
 491 void hmp_hostfwd_add(Monitor *mon, const QDict *qdict)
 492 {
 493     const char *redir_str;
 494     SlirpState *s;
 495     const char *arg1 = qdict_get_str(qdict, "arg1");
 496     const char *arg2 = qdict_get_try_str(qdict, "arg2");
 497     const char *arg3 = qdict_get_try_str(qdict, "arg3");
 498
 499     if (arg2) {
 500         s = slirp_lookup(mon, arg1, arg2);
 501         redir_str = arg3;
 502     } else {
 503         s = slirp_lookup(mon, NULL, NULL);
 504         redir_str = arg1;
 505     }
 506     if (s) {
 507         slirp_hostfwd(s, redir_str, 0);
 508     }
 509
 510 }
 511
 512 int net_slirp_redir(const char *redir_str)
 513 {
 514     struct slirp_config_str *config;
 515
 516     if (QTAILQ_EMPTY(&slirp_stacks)) {
 517         config = g_malloc(sizeof(*config));
 518         pstrcpy(config->str, sizeof(config->str), redir_str);
 519         config->flags = SLIRP_CFG_HOSTFWD | SLIRP_CFG_LEGACY;
 520         config->next = slirp_configs;
 521         slirp_configs = config;
 522         return 0;
 523     }
 524
 525     return slirp_hostfwd(QTAILQ_FIRST(&slirp_stacks), redir_str, 1);
 526 }
 527
 528 #ifndef _WIN32
 529
 530 /* automatic user mode samba server configuration */
 531 static void slirp_smb_cleanup(SlirpState *s)
 532 {
 533     char cmd[128];
 534     int ret;
 535
 536     if (s->smb_dir[0] != '\0') {
 537         snprintf(cmd, sizeof(cmd), "rm -rf %s", s->smb_dir);
 538         ret = system(cmd);
 539         if (ret == -1 || !WIFEXITED(ret)) {
 540             error_report("'%s' failed.", cmd);
 541         } else if (WEXITSTATUS(ret)) {
 542             error_report("'%s' failed. Error code: %d",
 543                          cmd, WEXITSTATUS(ret));
 544         }
 545         s->smb_dir[0] = '\0';
 546     }
 547 }
 548
 549 static int slirp_smb(SlirpState* s, const char *exported_dir,
 550                      struct in_addr vserver_addr)
 551 {
 552     char smb_conf[128];
 553     char smb_cmdline[128];
 554     struct passwd *passwd;
 555     FILE *f;
 556
 557     passwd = getpwuid(geteuid());
 558     if (!passwd) {
 559         error_report("failed to retrieve user name");
 560         return -1;
 561     }
 562
 563     if (access(CONFIG_SMBD_COMMAND, F_OK)) {
 564         error_report("could not find '%s', please install it",
 565                      CONFIG_SMBD_COMMAND);
 566         return -1;
 567     }
 568
 569     if (access(exported_dir, R_OK | X_OK)) {
 570         error_report("error accessing shared directory '%s': %s",
 571                      exported_dir, strerror(errno));
 572         return -1;
 573     }
 574
 575     snprintf(s->smb_dir, sizeof(s->smb_dir), "/tmp/qemu-smb.XXXXXX");
 576     if (!mkdtemp(s->smb_dir)) {
 577         error_report("could not create samba server dir '%s'", s->smb_dir);
 578         s->smb_dir[0] = 0;
 579         return -1;
 580     }
 581     snprintf(smb_conf, sizeof(smb_conf), "%s/%s", s->smb_dir, "smb.conf");
 582
 583     f = fopen(smb_conf, "w");
 584     if (!f) {
 585         slirp_smb_cleanup(s);
 586         error_report("could not create samba server configuration file '%s'",
 587                      smb_conf);
 588         return -1;
 589     }
 590     fprintf(f,
 591             "[global]\n"
 592             "private dir=%s\n"
 593             "interfaces=127.0.0.1\n"
 594             "bind interfaces only=yes\n"
 595             "pid directory=%s\n"
 596             "lock directory=%s\n"
 597             "state directory=%s\n"
 598             "cache directory=%s\n"
 599             "ncalrpc dir=%s/ncalrpc\n"
 600             "log file=%s/log.smbd\n"
 601             "smb passwd file=%s/smbpasswd\n"
 602             "security = user\n"
 603             "map to guest = Bad User\n"
 604             "load printers = no\n"
 605             "printing = bsd\n"
 606             "disable spoolss = yes\n"
 607             "usershare max shares = 0\n"
 608             "[qemu]\n"
 609             "path=%s\n"
 610             "read only=no\n"
 611             "guest ok=yes\n"
 612             "force user=%s\n",
 613             s->smb_dir,
 614             s->smb_dir,
 615             s->smb_dir,
 616             s->smb_dir,
 617             s->smb_dir,
 618             s->smb_dir,
 619             s->smb_dir,
 620             s->smb_dir,
 621             exported_dir,
 622             passwd->pw_name
 623             );
 624     fclose(f);
 625
 626     snprintf(smb_cmdline, sizeof(smb_cmdline), "%s -l %s -s %s",
 627              CONFIG_SMBD_COMMAND, s->smb_dir, smb_conf);
 628
 629     if (slirp_add_exec(s->slirp, 0, smb_cmdline, &vserver_addr, 139) < 0 ||
 630         slirp_add_exec(s->slirp, 0, smb_cmdline, &vserver_addr, 445) < 0) {
 631         slirp_smb_cleanup(s);
 632         error_report("conflicting/invalid smbserver address");
 633         return -1;
 634     }
 635     return 0;
 636 }
 637
 638 /* automatic user mode samba server configuration (legacy interface) */
 639 int net_slirp_smb(const char *exported_dir)
 640 {
 641     struct in_addr vserver_addr = { .s_addr = 0 };
 642
 643     if (legacy_smb_export) {
 644         fprintf(stderr, "-smb given twice\n");
 645         return -1;
 646     }
 647     legacy_smb_export = exported_dir;
 648     if (!QTAILQ_EMPTY(&slirp_stacks)) {
 649         return slirp_smb(QTAILQ_FIRST(&slirp_stacks), exported_dir,
 650                          vserver_addr);
 651     }
 652     return 0;
 653 }
 654
 655 #endif /* !defined(_WIN32) */
 656
 657 struct GuestFwd {
 658     CharDriverState *hd;
 659     struct in_addr server;
 660     int port;
 661     Slirp *slirp;
 662 };
 663
 664 static int guestfwd_can_read(void *opaque)
 665 {
 666     struct GuestFwd *fwd = opaque;
 667     return slirp_socket_can_recv(fwd->slirp, fwd->server, fwd->port);
 668 }
 669
 670 static void guestfwd_read(void *opaque, const uint8_t *buf, int size)
 671 {
 672     struct GuestFwd *fwd = opaque;
 673     slirp_socket_recv(fwd->slirp, fwd->server, fwd->port, buf, size);
 674 }
 675
 676 static int slirp_guestfwd(SlirpState *s, const char *config_str,
 677                           int legacy_format)
 678 {
 679     struct in_addr server = { .s_addr = 0 };
 680     struct GuestFwd *fwd;
 681     const char *p;
 682     char buf[128];
 683     char *end;
 684     int port;
 685
 686     p = config_str;
 687     if (legacy_format) {
 688         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 689             goto fail_syntax;
 690         }
 691     } else {
 692         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 693             goto fail_syntax;
 694         }
 695         if (strcmp(buf, "tcp") && buf[0] != '\0') {
 696             goto fail_syntax;
 697         }
 698         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 699             goto fail_syntax;
 700         }
 701         if (buf[0] != '\0' && !inet_aton(buf, &server)) {
 702             goto fail_syntax;
 703         }
 704         if (get_str_sep(buf, sizeof(buf), &p, '-') < 0) {
 705             goto fail_syntax;
 706         }
 707     }
 708     port = strtol(buf, &end, 10);
 709     if (*end != '\0' || port < 1 || port > 65535) {
 710         goto fail_syntax;
 711     }
 712
 713     snprintf(buf, sizeof(buf), "guestfwd.tcp.%d", port);
 714
 715     if ((strlen(p) > 4) && !strncmp(p, "cmd:", 4)) {
 716         if (slirp_add_exec(s->slirp, 0, &p[4], &server, port) < 0) {
 717             error_report("conflicting/invalid host:port in guest forwarding "
 718                          "rule '%s'", config_str);
 719             return -1;
 720         }
 721     } else {
 722         fwd = g_new(struct GuestFwd, 1);
 723         fwd->hd = qemu_chr_new(buf, p, NULL);
 724         if (!fwd->hd) {
 725             error_report("could not open guest forwarding device '%s'", buf);
 726             g_free(fwd);
 727             return -1;
 728         }
 729
 730         if (slirp_add_exec(s->slirp, 3, fwd->hd, &server, port) < 0) {
 731             error_report("conflicting/invalid host:port in guest forwarding "
 732                          "rule '%s'", config_str);
 733             g_free(fwd);
 734             return -1;
 735         }
 736         fwd->server = server;
 737         fwd->port = port;
 738         fwd->slirp = s->slirp;
 739
 740         qemu_chr_fe_claim_no_fail(fwd->hd);
 741         qemu_chr_add_handlers(fwd->hd, guestfwd_can_read, guestfwd_read,
 742                               NULL, fwd);
 743     }
 744     return 0;
 745
 746  fail_syntax:
 747     error_report("invalid guest forwarding rule '%s'", config_str);
 748     return -1;
 749 }
 750
 751 void hmp_info_usernet(Monitor *mon, const QDict *qdict)
 752 {
 753     SlirpState *s;
 754
 755     QTAILQ_FOREACH(s, &slirp_stacks, entry) {
 756         int id;
 757         bool got_vlan_id = net_hub_id_for_client(&s->nc, &id) == 0;
 758         monitor_printf(mon, "VLAN %d (%s):\n",
 759                        got_vlan_id ? id : -1,
 760                        s->nc.name);
 761         slirp_connection_info(s->slirp, mon);
 762     }
 763 }
 764
 765 static void
 766 net_init_slirp_configs(const StringList *fwd, int flags)
 767 {
 768     while (fwd) {
 769         struct slirp_config_str *config;
 770
 771         config = g_malloc0(sizeof(*config));
 772         pstrcpy(config->str, sizeof(config->str), fwd->value->str);
 773         config->flags = flags;
 774         config->next = slirp_configs;
 775         slirp_configs = config;
 776
 777         fwd = fwd->next;
 778     }
 779 }
 780
 781 static const char **slirp_dnssearch(const StringList *dnsname)
 782 {
 783     const StringList *c = dnsname;
 784     size_t i = 0, num_opts = 0;
 785     const char **ret;
 786
 787     while (c) {
 788         num_opts++;
 789         c = c->next;
 790     }
 791
 792     if (num_opts == 0) {
 793         return NULL;
 794     }
 795
 796     ret = g_malloc((num_opts + 1) * sizeof(*ret));
 797     c = dnsname;
 798     while (c) {
 799         ret[i++] = c->value->str;
 800         c = c->next;
 801     }
 802     ret[i] = NULL;
 803     return ret;
 804 }
 805
 806 int net_init_slirp(const NetClientOptions *opts, const char *name,
 807                    NetClientState *peer, Error **errp)
 808 {
 809     /* FIXME error_setg(errp, ...) on failure */
 810     struct slirp_config_str *config;
 811     char *vnet;
 812     int ret;
 813     const NetdevUserOptions *user;
 814     const char **dnssearch;
 815
 816     assert(opts->type == NET_CLIENT_OPTIONS_KIND_USER);
 817     user = opts->u.user;
 818
 819     vnet = user->has_net ? g_strdup(user->net) :
 820            user->has_ip  ? g_strdup_printf("%s/24", user->ip) :
 821            NULL;
 822
 823     dnssearch = slirp_dnssearch(user->dnssearch);
 824
 825     /* all optional fields are initialized to "all bits zero" */
 826
 827     net_init_slirp_configs(user->hostfwd, SLIRP_CFG_HOSTFWD);
 828     net_init_slirp_configs(user->guestfwd, 0);
 829
 830     ret = net_slirp_init(peer, "user", name, user->q_restrict, vnet,
 831                          user->host, user->ip6_prefix, user->ip6_prefixlen,
 832                          user->ip6_host, user->hostname, user->tftp,
 833                          user->bootfile, user->dhcpstart,
 834                          user->dns, user->ip6_dns, user->smb,
 835                          user->smbserver, dnssearch);
 836
 837     while (slirp_configs) {
 838         config = slirp_configs;
 839         slirp_configs = config->next;
 840         g_free(config);
 841     }
 842
 843     g_free(vnet);
 844     g_free(dnssearch);
 845
 846     return ret;
 847 }
 848
 849 int net_slirp_parse_legacy(QemuOptsList *opts_list, const char *optarg, int *ret)
 850 {
 851     if (strcmp(opts_list->name, "net") != 0 ||
 852         strncmp(optarg, "channel,", strlen("channel,")) != 0) {
 853         return 0;
 854     }
 855
 856     error_report("The '-net channel' option is deprecated. "
 857                  "Please use '-netdev user,guestfwd=...' instead.");
 858
 859     /* handle legacy -net channel,port:chr */
 860     optarg += strlen("channel,");
 861
 862     if (QTAILQ_EMPTY(&slirp_stacks)) {
 863         struct slirp_config_str *config;
 864
 865         config = g_malloc(sizeof(*config));
 866         pstrcpy(config->str, sizeof(config->str), optarg);
 867         config->flags = SLIRP_CFG_LEGACY;
 868         config->next = slirp_configs;
 869         slirp_configs = config;
 870         *ret = 0;
 871     } else {
 872         *ret = slirp_guestfwd(QTAILQ_FIRST(&slirp_stacks), optarg, 1);
 873     }
 874
 875     return 1;
 876 }
 877