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 #include "qemu/cutils.h"
  42
  43 static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
  44 {
  45     const char *p, *p1;
  46     int len;
  47     p = *pp;
  48     p1 = strchr(p, sep);
  49     if (!p1)
  50         return -1;
  51     len = p1 - p;
  52     p1++;
  53     if (buf_size > 0) {
  54         if (len > buf_size - 1)
  55             len = buf_size - 1;
  56         memcpy(buf, p, len);
  57         buf[len] = '\0';
  58     }
  59     *pp = p1;
  60     return 0;
  61 }
  62
  63 /* slirp network adapter */
  64
  65 #define SLIRP_CFG_HOSTFWD 1
  66 #define SLIRP_CFG_LEGACY  2
  67
  68 struct slirp_config_str {
  69     struct slirp_config_str *next;
  70     int flags;
  71     char str[1024];
  72     int legacy_format;
  73 };
  74
  75 typedef struct SlirpState {
  76     NetClientState nc;
  77     QTAILQ_ENTRY(SlirpState) entry;
  78     Slirp *slirp;
  79 #ifndef _WIN32
  80     char smb_dir[128];
  81 #endif
  82 } SlirpState;
  83
  84 static struct slirp_config_str *slirp_configs;
  85 const char *legacy_tftp_prefix;
  86 const char *legacy_bootp_filename;
  87 static QTAILQ_HEAD(slirp_stacks, SlirpState) slirp_stacks =
  88     QTAILQ_HEAD_INITIALIZER(slirp_stacks);
  89
  90 static int slirp_hostfwd(SlirpState *s, const char *redir_str,
  91                          int legacy_format);
  92 static int slirp_guestfwd(SlirpState *s, const char *config_str,
  93                           int legacy_format);
  94
  95 #ifndef _WIN32
  96 static const char *legacy_smb_export;
  97
  98 static int slirp_smb(SlirpState *s, const char *exported_dir,
  99                      struct in_addr vserver_addr);
 100 static void slirp_smb_cleanup(SlirpState *s);
 101 #else
 102 static inline void slirp_smb_cleanup(SlirpState *s) { }
 103 #endif
 104
 105 void slirp_output(void *opaque, const uint8_t *pkt, int pkt_len)
 106 {
 107     SlirpState *s = opaque;
 108
 109     qemu_send_packet(&s->nc, pkt, pkt_len);
 110 }
 111
 112 static ssize_t net_slirp_receive(NetClientState *nc, const uint8_t *buf, size_t size)
 113 {
 114     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
 115
 116     slirp_input(s->slirp, buf, size);
 117
 118     return size;
 119 }
 120
 121 static void net_slirp_cleanup(NetClientState *nc)
 122 {
 123     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
 124
 125     slirp_cleanup(s->slirp);
 126     slirp_smb_cleanup(s);
 127     QTAILQ_REMOVE(&slirp_stacks, s, entry);
 128 }
 129
 130 static NetClientInfo net_slirp_info = {
 131     .type = NET_CLIENT_OPTIONS_KIND_USER,
 132     .size = sizeof(SlirpState),
 133     .receive = net_slirp_receive,
 134     .cleanup = net_slirp_cleanup,
 135 };
 136
 137 static int net_slirp_init(NetClientState *peer, const char *model,
 138                           const char *name, int restricted,
 139                           const char *vnetwork, const char *vhost,
 140                           const char *vprefix6, int vprefix6_len,
 141                           const char *vhost6,
 142                           const char *vhostname, const char *tftp_export,
 143                           const char *bootfile, const char *vdhcp_start,
 144                           const char *vnameserver, const char *vnameserver6,
 145                           const char *smb_export, const char *vsmbserver,
 146                           const char **dnssearch)
 147 {
 148     /* default settings according to historic slirp */
 149     struct in_addr net  = { .s_addr = htonl(0x0a000200) }; /* 10.0.2.0 */
 150     struct in_addr mask = { .s_addr = htonl(0xffffff00) }; /* 255.255.255.0 */
 151     struct in_addr host = { .s_addr = htonl(0x0a000202) }; /* 10.0.2.2 */
 152     struct in_addr dhcp = { .s_addr = htonl(0x0a00020f) }; /* 10.0.2.15 */
 153     struct in_addr dns  = { .s_addr = htonl(0x0a000203) }; /* 10.0.2.3 */
 154     struct in6_addr ip6_prefix;
 155     struct in6_addr ip6_host;
 156     struct in6_addr ip6_dns;
 157 #ifndef _WIN32
 158     struct in_addr smbsrv = { .s_addr = 0 };
 159 #endif
 160     NetClientState *nc;
 161     SlirpState *s;
 162     char buf[20];
 163     uint32_t addr;
 164     int shift;
 165     char *end;
 166     struct slirp_config_str *config;
 167
 168     if (!tftp_export) {
 169         tftp_export = legacy_tftp_prefix;
 170     }
 171     if (!bootfile) {
 172         bootfile = legacy_bootp_filename;
 173     }
 174
 175     if (vnetwork) {
 176         if (get_str_sep(buf, sizeof(buf), &vnetwork, '/') < 0) {
 177             if (!inet_aton(vnetwork, &net)) {
 178                 return -1;
 179             }
 180             addr = ntohl(net.s_addr);
 181             if (!(addr & 0x80000000)) {
 182                 mask.s_addr = htonl(0xff000000); /* class A */
 183             } else if ((addr & 0xfff00000) == 0xac100000) {
 184                 mask.s_addr = htonl(0xfff00000); /* priv. 172.16.0.0/12 */
 185             } else if ((addr & 0xc0000000) == 0x80000000) {
 186                 mask.s_addr = htonl(0xffff0000); /* class B */
 187             } else if ((addr & 0xffff0000) == 0xc0a80000) {
 188                 mask.s_addr = htonl(0xffff0000); /* priv. 192.168.0.0/16 */
 189             } else if ((addr & 0xffff0000) == 0xc6120000) {
 190                 mask.s_addr = htonl(0xfffe0000); /* tests 198.18.0.0/15 */
 191             } else if ((addr & 0xe0000000) == 0xe0000000) {
 192                 mask.s_addr = htonl(0xffffff00); /* class C */
 193             } else {
 194                 mask.s_addr = htonl(0xfffffff0); /* multicast/reserved */
 195             }
 196         } else {
 197             if (!inet_aton(buf, &net)) {
 198                 return -1;
 199             }
 200             shift = strtol(vnetwork, &end, 10);
 201             if (*end != '\0') {
 202                 if (!inet_aton(vnetwork, &mask)) {
 203                     return -1;
 204                 }
 205             } else if (shift < 4 || shift > 32) {
 206                 return -1;
 207             } else {
 208                 mask.s_addr = htonl(0xffffffff << (32 - shift));
 209             }
 210         }
 211         net.s_addr &= mask.s_addr;
 212         host.s_addr = net.s_addr | (htonl(0x0202) & ~mask.s_addr);
 213         dhcp.s_addr = net.s_addr | (htonl(0x020f) & ~mask.s_addr);
 214         dns.s_addr  = net.s_addr | (htonl(0x0203) & ~mask.s_addr);
 215     }
 216
 217     if (vhost && !inet_aton(vhost, &host)) {
 218         return -1;
 219     }
 220     if ((host.s_addr & mask.s_addr) != net.s_addr) {
 221         return -1;
 222     }
 223
 224     if (vnameserver && !inet_aton(vnameserver, &dns)) {
 225         return -1;
 226     }
 227     if ((dns.s_addr & mask.s_addr) != net.s_addr ||
 228         dns.s_addr == host.s_addr) {
 229         return -1;
 230     }
 231
 232     if (vdhcp_start && !inet_aton(vdhcp_start, &dhcp)) {
 233         return -1;
 234     }
 235     if ((dhcp.s_addr & mask.s_addr) != net.s_addr ||
 236         dhcp.s_addr == host.s_addr || dhcp.s_addr == dns.s_addr) {
 237         return -1;
 238     }
 239
 240 #ifndef _WIN32
 241     if (vsmbserver && !inet_aton(vsmbserver, &smbsrv)) {
 242         return -1;
 243     }
 244 #endif
 245
 246 #if defined(_WIN32) && (_WIN32_WINNT < 0x0600)
 247     /* No inet_pton helper before Vista... */
 248     if (vprefix6) {
 249         /* Unsupported */
 250         return -1;
 251     }
 252     memset(&ip6_prefix, 0, sizeof(ip6_prefix));
 253     ip6_prefix.s6_addr[0] = 0xfe;
 254     ip6_prefix.s6_addr[1] = 0xc0;
 255 #else
 256     if (!vprefix6) {
 257         vprefix6 = "fec0::";
 258     }
 259     if (!inet_pton(AF_INET6, vprefix6, &ip6_prefix)) {
 260         return -1;
 261     }
 262 #endif
 263
 264     if (!vprefix6_len) {
 265         vprefix6_len = 64;
 266     }
 267     if (vprefix6_len < 0 || vprefix6_len > 126) {
 268         return -1;
 269     }
 270
 271     if (vhost6) {
 272 #if defined(_WIN32) && (_WIN32_WINNT < 0x0600)
 273         return -1;
 274 #else
 275         if (!inet_pton(AF_INET6, vhost6, &ip6_host)) {
 276             return -1;
 277         }
 278         if (!in6_equal_net(&ip6_prefix, &ip6_host, vprefix6_len)) {
 279             return -1;
 280         }
 281 #endif
 282     } else {
 283         ip6_host = ip6_prefix;
 284         ip6_host.s6_addr[15] |= 2;
 285     }
 286
 287     if (vnameserver6) {
 288 #if defined(_WIN32) && (_WIN32_WINNT < 0x0600)
 289         return -1;
 290 #else
 291         if (!inet_pton(AF_INET6, vnameserver6, &ip6_dns)) {
 292             return -1;
 293         }
 294         if (!in6_equal_net(&ip6_prefix, &ip6_dns, vprefix6_len)) {
 295             return -1;
 296         }
 297 #endif
 298     } else {
 299         ip6_dns = ip6_prefix;
 300         ip6_dns.s6_addr[15] |= 3;
 301     }
 302
 303
 304     nc = qemu_new_net_client(&net_slirp_info, peer, model, name);
 305
 306     snprintf(nc->info_str, sizeof(nc->info_str),
 307              "net=%s,restrict=%s", inet_ntoa(net),
 308              restricted ? "on" : "off");
 309
 310     s = DO_UPCAST(SlirpState, nc, nc);
 311
 312     s->slirp = slirp_init(restricted, net, mask, host,
 313                           ip6_prefix, vprefix6_len, ip6_host,
 314                           vhostname, tftp_export, bootfile, dhcp,
 315                           dns, ip6_dns, dnssearch, s);
 316     QTAILQ_INSERT_TAIL(&slirp_stacks, s, entry);
 317
 318     for (config = slirp_configs; config; config = config->next) {
 319         if (config->flags & SLIRP_CFG_HOSTFWD) {
 320             if (slirp_hostfwd(s, config->str,
 321                               config->flags & SLIRP_CFG_LEGACY) < 0)
 322                 goto error;
 323         } else {
 324             if (slirp_guestfwd(s, config->str,
 325                                config->flags & SLIRP_CFG_LEGACY) < 0)
 326                 goto error;
 327         }
 328     }
 329 #ifndef _WIN32
 330     if (!smb_export) {
 331         smb_export = legacy_smb_export;
 332     }
 333     if (smb_export) {
 334         if (slirp_smb(s, smb_export, smbsrv) < 0)
 335             goto error;
 336     }
 337 #endif
 338
 339     return 0;
 340
 341 error:
 342     qemu_del_net_client(nc);
 343     return -1;
 344 }
 345
 346 static SlirpState *slirp_lookup(Monitor *mon, const char *vlan,
 347                                 const char *stack)
 348 {
 349
 350     if (vlan) {
 351         NetClientState *nc;
 352         nc = net_hub_find_client_by_name(strtol(vlan, NULL, 0), stack);
 353         if (!nc) {
 354             monitor_printf(mon, "unrecognized (vlan-id, stackname) pair\n");
 355             return NULL;
 356         }
 357         if (strcmp(nc->model, "user")) {
 358             monitor_printf(mon, "invalid device specified\n");
 359             return NULL;
 360         }
 361         return DO_UPCAST(SlirpState, nc, nc);
 362     } else {
 363         if (QTAILQ_EMPTY(&slirp_stacks)) {
 364             monitor_printf(mon, "user mode network stack not in use\n");
 365             return NULL;
 366         }
 367         return QTAILQ_FIRST(&slirp_stacks);
 368     }
 369 }
 370
 371 void hmp_hostfwd_remove(Monitor *mon, const QDict *qdict)
 372 {
 373     struct in_addr host_addr = { .s_addr = INADDR_ANY };
 374     int host_port;
 375     char buf[256];
 376     const char *src_str, *p;
 377     SlirpState *s;
 378     int is_udp = 0;
 379     int err;
 380     const char *arg1 = qdict_get_str(qdict, "arg1");
 381     const char *arg2 = qdict_get_try_str(qdict, "arg2");
 382     const char *arg3 = qdict_get_try_str(qdict, "arg3");
 383
 384     if (arg2) {
 385         s = slirp_lookup(mon, arg1, arg2);
 386         src_str = arg3;
 387     } else {
 388         s = slirp_lookup(mon, NULL, NULL);
 389         src_str = arg1;
 390     }
 391     if (!s) {
 392         return;
 393     }
 394
 395     p = src_str;
 396     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 397         goto fail_syntax;
 398     }
 399
 400     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
 401         is_udp = 0;
 402     } else if (!strcmp(buf, "udp")) {
 403         is_udp = 1;
 404     } else {
 405         goto fail_syntax;
 406     }
 407
 408     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 409         goto fail_syntax;
 410     }
 411     if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
 412         goto fail_syntax;
 413     }
 414
 415     host_port = atoi(p);
 416
 417     err = slirp_remove_hostfwd(s->slirp, is_udp, host_addr, host_port);
 418
 419     monitor_printf(mon, "host forwarding rule for %s %s\n", src_str,
 420                    err ? "not found" : "removed");
 421     return;
 422
 423  fail_syntax:
 424     monitor_printf(mon, "invalid format\n");
 425 }
 426
 427 static int slirp_hostfwd(SlirpState *s, const char *redir_str,
 428                          int legacy_format)
 429 {
 430     struct in_addr host_addr = { .s_addr = INADDR_ANY };
 431     struct in_addr guest_addr = { .s_addr = 0 };
 432     int host_port, guest_port;
 433     const char *p;
 434     char buf[256];
 435     int is_udp;
 436     char *end;
 437
 438     p = redir_str;
 439     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 440         goto fail_syntax;
 441     }
 442     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
 443         is_udp = 0;
 444     } else if (!strcmp(buf, "udp")) {
 445         is_udp = 1;
 446     } else {
 447         goto fail_syntax;
 448     }
 449
 450     if (!legacy_format) {
 451         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 452             goto fail_syntax;
 453         }
 454         if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
 455             goto fail_syntax;
 456         }
 457     }
 458
 459     if (get_str_sep(buf, sizeof(buf), &p, legacy_format ? ':' : '-') < 0) {
 460         goto fail_syntax;
 461     }
 462     host_port = strtol(buf, &end, 0);
 463     if (*end != '\0' || host_port < 1 || host_port > 65535) {
 464         goto fail_syntax;
 465     }
 466
 467     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 468         goto fail_syntax;
 469     }
 470     if (buf[0] != '\0' && !inet_aton(buf, &guest_addr)) {
 471         goto fail_syntax;
 472     }
 473
 474     guest_port = strtol(p, &end, 0);
 475     if (*end != '\0' || guest_port < 1 || guest_port > 65535) {
 476         goto fail_syntax;
 477     }
 478
 479     if (slirp_add_hostfwd(s->slirp, is_udp, host_addr, host_port, guest_addr,
 480                           guest_port) < 0) {
 481         error_report("could not set up host forwarding rule '%s'",
 482                      redir_str);
 483         return -1;
 484     }
 485     return 0;
 486
 487  fail_syntax:
 488     error_report("invalid host forwarding rule '%s'", redir_str);
 489     return -1;
 490 }
 491
 492 void hmp_hostfwd_add(Monitor *mon, const QDict *qdict)
 493 {
 494     const char *redir_str;
 495     SlirpState *s;
 496     const char *arg1 = qdict_get_str(qdict, "arg1");
 497     const char *arg2 = qdict_get_try_str(qdict, "arg2");
 498     const char *arg3 = qdict_get_try_str(qdict, "arg3");
 499
 500     if (arg2) {
 501         s = slirp_lookup(mon, arg1, arg2);
 502         redir_str = arg3;
 503     } else {
 504         s = slirp_lookup(mon, NULL, NULL);
 505         redir_str = arg1;
 506     }
 507     if (s) {
 508         slirp_hostfwd(s, redir_str, 0);
 509     }
 510
 511 }
 512
 513 int net_slirp_redir(const char *redir_str)
 514 {
 515     struct slirp_config_str *config;
 516
 517     if (QTAILQ_EMPTY(&slirp_stacks)) {
 518         config = g_malloc(sizeof(*config));
 519         pstrcpy(config->str, sizeof(config->str), redir_str);
 520         config->flags = SLIRP_CFG_HOSTFWD | SLIRP_CFG_LEGACY;
 521         config->next = slirp_configs;
 522         slirp_configs = config;
 523         return 0;
 524     }
 525
 526     return slirp_hostfwd(QTAILQ_FIRST(&slirp_stacks), redir_str, 1);
 527 }
 528
 529 #ifndef _WIN32
 530
 531 /* automatic user mode samba server configuration */
 532 static void slirp_smb_cleanup(SlirpState *s)
 533 {
 534     char cmd[128];
 535     int ret;
 536
 537     if (s->smb_dir[0] != '\0') {
 538         snprintf(cmd, sizeof(cmd), "rm -rf %s", s->smb_dir);
 539         ret = system(cmd);
 540         if (ret == -1 || !WIFEXITED(ret)) {
 541             error_report("'%s' failed.", cmd);
 542         } else if (WEXITSTATUS(ret)) {
 543             error_report("'%s' failed. Error code: %d",
 544                          cmd, WEXITSTATUS(ret));
 545         }
 546         s->smb_dir[0] = '\0';
 547     }
 548 }
 549
 550 static int slirp_smb(SlirpState* s, const char *exported_dir,
 551                      struct in_addr vserver_addr)
 552 {
 553     char smb_conf[128];
 554     char smb_cmdline[128];
 555     struct passwd *passwd;
 556     FILE *f;
 557
 558     passwd = getpwuid(geteuid());
 559     if (!passwd) {
 560         error_report("failed to retrieve user name");
 561         return -1;
 562     }
 563
 564     if (access(CONFIG_SMBD_COMMAND, F_OK)) {
 565         error_report("could not find '%s', please install it",
 566                      CONFIG_SMBD_COMMAND);
 567         return -1;
 568     }
 569
 570     if (access(exported_dir, R_OK | X_OK)) {
 571         error_report("error accessing shared directory '%s': %s",
 572                      exported_dir, strerror(errno));
 573         return -1;
 574     }
 575
 576     snprintf(s->smb_dir, sizeof(s->smb_dir), "/tmp/qemu-smb.XXXXXX");
 577     if (!mkdtemp(s->smb_dir)) {
 578         error_report("could not create samba server dir '%s'", s->smb_dir);
 579         s->smb_dir[0] = 0;
 580         return -1;
 581     }
 582     snprintf(smb_conf, sizeof(smb_conf), "%s/%s", s->smb_dir, "smb.conf");
 583
 584     f = fopen(smb_conf, "w");
 585     if (!f) {
 586         slirp_smb_cleanup(s);
 587         error_report("could not create samba server configuration file '%s'",
 588                      smb_conf);
 589         return -1;
 590     }
 591     fprintf(f,
 592             "[global]\n"
 593             "private dir=%s\n"
 594             "interfaces=127.0.0.1\n"
 595             "bind interfaces only=yes\n"
 596             "pid directory=%s\n"
 597             "lock directory=%s\n"
 598             "state directory=%s\n"
 599             "cache directory=%s\n"
 600             "ncalrpc dir=%s/ncalrpc\n"
 601             "log file=%s/log.smbd\n"
 602             "smb passwd file=%s/smbpasswd\n"
 603             "security = user\n"
 604             "map to guest = Bad User\n"
 605             "load printers = no\n"
 606             "printing = bsd\n"
 607             "disable spoolss = yes\n"
 608             "usershare max shares = 0\n"
 609             "[qemu]\n"
 610             "path=%s\n"
 611             "read only=no\n"
 612             "guest ok=yes\n"
 613             "force user=%s\n",
 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             s->smb_dir,
 622             exported_dir,
 623             passwd->pw_name
 624             );
 625     fclose(f);
 626
 627     snprintf(smb_cmdline, sizeof(smb_cmdline), "%s -l %s -s %s",
 628              CONFIG_SMBD_COMMAND, s->smb_dir, smb_conf);
 629
 630     if (slirp_add_exec(s->slirp, 0, smb_cmdline, &vserver_addr, 139) < 0 ||
 631         slirp_add_exec(s->slirp, 0, smb_cmdline, &vserver_addr, 445) < 0) {
 632         slirp_smb_cleanup(s);
 633         error_report("conflicting/invalid smbserver address");
 634         return -1;
 635     }
 636     return 0;
 637 }
 638
 639 /* automatic user mode samba server configuration (legacy interface) */
 640 int net_slirp_smb(const char *exported_dir)
 641 {
 642     struct in_addr vserver_addr = { .s_addr = 0 };
 643
 644     if (legacy_smb_export) {
 645         fprintf(stderr, "-smb given twice\n");
 646         return -1;
 647     }
 648     legacy_smb_export = exported_dir;
 649     if (!QTAILQ_EMPTY(&slirp_stacks)) {
 650         return slirp_smb(QTAILQ_FIRST(&slirp_stacks), exported_dir,
 651                          vserver_addr);
 652     }
 653     return 0;
 654 }
 655
 656 #endif /* !defined(_WIN32) */
 657
 658 struct GuestFwd {
 659     CharDriverState *hd;
 660     struct in_addr server;
 661     int port;
 662     Slirp *slirp;
 663 };
 664
 665 static int guestfwd_can_read(void *opaque)
 666 {
 667     struct GuestFwd *fwd = opaque;
 668     return slirp_socket_can_recv(fwd->slirp, fwd->server, fwd->port);
 669 }
 670
 671 static void guestfwd_read(void *opaque, const uint8_t *buf, int size)
 672 {
 673     struct GuestFwd *fwd = opaque;
 674     slirp_socket_recv(fwd->slirp, fwd->server, fwd->port, buf, size);
 675 }
 676
 677 static int slirp_guestfwd(SlirpState *s, const char *config_str,
 678                           int legacy_format)
 679 {
 680     struct in_addr server = { .s_addr = 0 };
 681     struct GuestFwd *fwd;
 682     const char *p;
 683     char buf[128];
 684     char *end;
 685     int port;
 686
 687     p = config_str;
 688     if (legacy_format) {
 689         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 690             goto fail_syntax;
 691         }
 692     } else {
 693         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 694             goto fail_syntax;
 695         }
 696         if (strcmp(buf, "tcp") && buf[0] != '\0') {
 697             goto fail_syntax;
 698         }
 699         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 700             goto fail_syntax;
 701         }
 702         if (buf[0] != '\0' && !inet_aton(buf, &server)) {
 703             goto fail_syntax;
 704         }
 705         if (get_str_sep(buf, sizeof(buf), &p, '-') < 0) {
 706             goto fail_syntax;
 707         }
 708     }
 709     port = strtol(buf, &end, 10);
 710     if (*end != '\0' || port < 1 || port > 65535) {
 711         goto fail_syntax;
 712     }
 713
 714     snprintf(buf, sizeof(buf), "guestfwd.tcp.%d", port);
 715
 716     if ((strlen(p) > 4) && !strncmp(p, "cmd:", 4)) {
 717         if (slirp_add_exec(s->slirp, 0, &p[4], &server, port) < 0) {
 718             error_report("conflicting/invalid host:port in guest forwarding "
 719                          "rule '%s'", config_str);
 720             return -1;
 721         }
 722     } else {
 723         fwd = g_new(struct GuestFwd, 1);
 724         fwd->hd = qemu_chr_new(buf, p, NULL);
 725         if (!fwd->hd) {
 726             error_report("could not open guest forwarding device '%s'", buf);
 727             g_free(fwd);
 728             return -1;
 729         }
 730
 731         if (slirp_add_exec(s->slirp, 3, fwd->hd, &server, port) < 0) {
 732             error_report("conflicting/invalid host:port in guest forwarding "
 733                          "rule '%s'", config_str);
 734             g_free(fwd);
 735             return -1;
 736         }
 737         fwd->server = server;
 738         fwd->port = port;
 739         fwd->slirp = s->slirp;
 740
 741         qemu_chr_fe_claim_no_fail(fwd->hd);
 742         qemu_chr_add_handlers(fwd->hd, guestfwd_can_read, guestfwd_read,
 743                               NULL, fwd);
 744     }
 745     return 0;
 746
 747  fail_syntax:
 748     error_report("invalid guest forwarding rule '%s'", config_str);
 749     return -1;
 750 }
 751
 752 void hmp_info_usernet(Monitor *mon, const QDict *qdict)
 753 {
 754     SlirpState *s;
 755
 756     QTAILQ_FOREACH(s, &slirp_stacks, entry) {
 757         int id;
 758         bool got_vlan_id = net_hub_id_for_client(&s->nc, &id) == 0;
 759         monitor_printf(mon, "VLAN %d (%s):\n",
 760                        got_vlan_id ? id : -1,
 761                        s->nc.name);
 762         slirp_connection_info(s->slirp, mon);
 763     }
 764 }
 765
 766 static void
 767 net_init_slirp_configs(const StringList *fwd, int flags)
 768 {
 769     while (fwd) {
 770         struct slirp_config_str *config;
 771
 772         config = g_malloc0(sizeof(*config));
 773         pstrcpy(config->str, sizeof(config->str), fwd->value->str);
 774         config->flags = flags;
 775         config->next = slirp_configs;
 776         slirp_configs = config;
 777
 778         fwd = fwd->next;
 779     }
 780 }
 781
 782 static const char **slirp_dnssearch(const StringList *dnsname)
 783 {
 784     const StringList *c = dnsname;
 785     size_t i = 0, num_opts = 0;
 786     const char **ret;
 787
 788     while (c) {
 789         num_opts++;
 790         c = c->next;
 791     }
 792
 793     if (num_opts == 0) {
 794         return NULL;
 795     }
 796
 797     ret = g_malloc((num_opts + 1) * sizeof(*ret));
 798     c = dnsname;
 799     while (c) {
 800         ret[i++] = c->value->str;
 801         c = c->next;
 802     }
 803     ret[i] = NULL;
 804     return ret;
 805 }
 806
 807 int net_init_slirp(const NetClientOptions *opts, const char *name,
 808                    NetClientState *peer, Error **errp)
 809 {
 810     /* FIXME error_setg(errp, ...) on failure */
 811     struct slirp_config_str *config;
 812     char *vnet;
 813     int ret;
 814     const NetdevUserOptions *user;
 815     const char **dnssearch;
 816
 817     assert(opts->type == NET_CLIENT_OPTIONS_KIND_USER);
 818     user = opts->u.user.data;
 819
 820     vnet = user->has_net ? g_strdup(user->net) :
 821            user->has_ip  ? g_strdup_printf("%s/24", user->ip) :
 822            NULL;
 823
 824     dnssearch = slirp_dnssearch(user->dnssearch);
 825
 826     /* all optional fields are initialized to "all bits zero" */
 827
 828     net_init_slirp_configs(user->hostfwd, SLIRP_CFG_HOSTFWD);
 829     net_init_slirp_configs(user->guestfwd, 0);
 830
 831     ret = net_slirp_init(peer, "user", name, user->q_restrict, vnet,
 832                          user->host, user->ipv6_prefix, user->ipv6_prefixlen,
 833                          user->ipv6_host, user->hostname, user->tftp,
 834                          user->bootfile, user->dhcpstart,
 835                          user->dns, user->ipv6_dns, user->smb,
 836                          user->smbserver, dnssearch);
 837
 838     while (slirp_configs) {
 839         config = slirp_configs;
 840         slirp_configs = config->next;
 841         g_free(config);
 842     }
 843
 844     g_free(vnet);
 845     g_free(dnssearch);
 846
 847     return ret;
 848 }
 849
 850 int net_slirp_parse_legacy(QemuOptsList *opts_list, const char *optarg, int *ret)
 851 {
 852     if (strcmp(opts_list->name, "net") != 0 ||
 853         strncmp(optarg, "channel,", strlen("channel,")) != 0) {
 854         return 0;
 855     }
 856
 857     error_report("The '-net channel' option is deprecated. "
 858                  "Please use '-netdev user,guestfwd=...' instead.");
 859
 860     /* handle legacy -net channel,port:chr */
 861     optarg += strlen("channel,");
 862
 863     if (QTAILQ_EMPTY(&slirp_stacks)) {
 864         struct slirp_config_str *config;
 865
 866         config = g_malloc(sizeof(*config));
 867         pstrcpy(config->str, sizeof(config->str), optarg);
 868         config->flags = SLIRP_CFG_LEGACY;
 869         config->next = slirp_configs;
 870         slirp_configs = config;
 871         *ret = 0;
 872     } else {
 873         *ret = slirp_guestfwd(QTAILQ_FIRST(&slirp_stacks), optarg, 1);
 874     }
 875
 876     return 1;
 877 }
 878