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 "sysemu/sysemu.h"
  42 #include "qemu/cutils.h"
  43
  44 static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
  45 {
  46     const char *p, *p1;
  47     int len;
  48     p = *pp;
  49     p1 = strchr(p, sep);
  50     if (!p1)
  51         return -1;
  52     len = p1 - p;
  53     p1++;
  54     if (buf_size > 0) {
  55         if (len > buf_size - 1)
  56             len = buf_size - 1;
  57         memcpy(buf, p, len);
  58         buf[len] = '\0';
  59     }
  60     *pp = p1;
  61     return 0;
  62 }
  63
  64 /* slirp network adapter */
  65
  66 #define SLIRP_CFG_HOSTFWD 1
  67 #define SLIRP_CFG_LEGACY  2
  68
  69 struct slirp_config_str {
  70     struct slirp_config_str *next;
  71     int flags;
  72     char str[1024];
  73     int legacy_format;
  74 };
  75
  76 typedef struct SlirpState {
  77     NetClientState nc;
  78     QTAILQ_ENTRY(SlirpState) entry;
  79     Slirp *slirp;
  80     Notifier exit_notifier;
  81 #ifndef _WIN32
  82     char smb_dir[128];
  83 #endif
  84 } SlirpState;
  85
  86 static struct slirp_config_str *slirp_configs;
  87 const char *legacy_tftp_prefix;
  88 const char *legacy_bootp_filename;
  89 static QTAILQ_HEAD(slirp_stacks, SlirpState) slirp_stacks =
  90     QTAILQ_HEAD_INITIALIZER(slirp_stacks);
  91
  92 static int slirp_hostfwd(SlirpState *s, const char *redir_str,
  93                          int legacy_format);
  94 static int slirp_guestfwd(SlirpState *s, const char *config_str,
  95                           int legacy_format);
  96
  97 #ifndef _WIN32
  98 static const char *legacy_smb_export;
  99
 100 static int slirp_smb(SlirpState *s, const char *exported_dir,
 101                      struct in_addr vserver_addr);
 102 static void slirp_smb_cleanup(SlirpState *s);
 103 #else
 104 static inline void slirp_smb_cleanup(SlirpState *s) { }
 105 #endif
 106
 107 void slirp_output(void *opaque, const uint8_t *pkt, int pkt_len)
 108 {
 109     SlirpState *s = opaque;
 110
 111     qemu_send_packet(&s->nc, pkt, pkt_len);
 112 }
 113
 114 static ssize_t net_slirp_receive(NetClientState *nc, const uint8_t *buf, size_t size)
 115 {
 116     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
 117
 118     slirp_input(s->slirp, buf, size);
 119
 120     return size;
 121 }
 122
 123 static void slirp_smb_exit(Notifier *n, void *data)
 124 {
 125     SlirpState *s = container_of(n, SlirpState, exit_notifier);
 126     slirp_smb_cleanup(s);
 127 }
 128
 129 static void net_slirp_cleanup(NetClientState *nc)
 130 {
 131     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
 132
 133     slirp_cleanup(s->slirp);
 134     qemu_remove_exit_notifier(&s->exit_notifier);
 135     slirp_smb_cleanup(s);
 136     QTAILQ_REMOVE(&slirp_stacks, s, entry);
 137 }
 138
 139 static NetClientInfo net_slirp_info = {
 140     .type = NET_CLIENT_OPTIONS_KIND_USER,
 141     .size = sizeof(SlirpState),
 142     .receive = net_slirp_receive,
 143     .cleanup = net_slirp_cleanup,
 144 };
 145
 146 static int net_slirp_init(NetClientState *peer, const char *model,
 147                           const char *name, int restricted,
 148                           bool ipv4, const char *vnetwork, const char *vhost,
 149                           bool ipv6, const char *vprefix6, int vprefix6_len,
 150                           const char *vhost6,
 151                           const char *vhostname, const char *tftp_export,
 152                           const char *bootfile, const char *vdhcp_start,
 153                           const char *vnameserver, const char *vnameserver6,
 154                           const char *smb_export, const char *vsmbserver,
 155                           const char **dnssearch)
 156 {
 157     /* default settings according to historic slirp */
 158     struct in_addr net  = { .s_addr = htonl(0x0a000200) }; /* 10.0.2.0 */
 159     struct in_addr mask = { .s_addr = htonl(0xffffff00) }; /* 255.255.255.0 */
 160     struct in_addr host = { .s_addr = htonl(0x0a000202) }; /* 10.0.2.2 */
 161     struct in_addr dhcp = { .s_addr = htonl(0x0a00020f) }; /* 10.0.2.15 */
 162     struct in_addr dns  = { .s_addr = htonl(0x0a000203) }; /* 10.0.2.3 */
 163     struct in6_addr ip6_prefix;
 164     struct in6_addr ip6_host;
 165     struct in6_addr ip6_dns;
 166 #ifndef _WIN32
 167     struct in_addr smbsrv = { .s_addr = 0 };
 168 #endif
 169     NetClientState *nc;
 170     SlirpState *s;
 171     char buf[20];
 172     uint32_t addr;
 173     int shift;
 174     char *end;
 175     struct slirp_config_str *config;
 176
 177     if (!ipv4 && (vnetwork || vhost || vnameserver)) {
 178         return -1;
 179     }
 180
 181     if (!ipv6 && (vprefix6 || vhost6 || vnameserver6)) {
 182         return -1;
 183     }
 184
 185     if (!ipv4 && !ipv6) {
 186         /* It doesn't make sense to disable both */
 187         return -1;
 188     }
 189
 190     if (!tftp_export) {
 191         tftp_export = legacy_tftp_prefix;
 192     }
 193     if (!bootfile) {
 194         bootfile = legacy_bootp_filename;
 195     }
 196
 197     if (vnetwork) {
 198         if (get_str_sep(buf, sizeof(buf), &vnetwork, '/') < 0) {
 199             if (!inet_aton(vnetwork, &net)) {
 200                 return -1;
 201             }
 202             addr = ntohl(net.s_addr);
 203             if (!(addr & 0x80000000)) {
 204                 mask.s_addr = htonl(0xff000000); /* class A */
 205             } else if ((addr & 0xfff00000) == 0xac100000) {
 206                 mask.s_addr = htonl(0xfff00000); /* priv. 172.16.0.0/12 */
 207             } else if ((addr & 0xc0000000) == 0x80000000) {
 208                 mask.s_addr = htonl(0xffff0000); /* class B */
 209             } else if ((addr & 0xffff0000) == 0xc0a80000) {
 210                 mask.s_addr = htonl(0xffff0000); /* priv. 192.168.0.0/16 */
 211             } else if ((addr & 0xffff0000) == 0xc6120000) {
 212                 mask.s_addr = htonl(0xfffe0000); /* tests 198.18.0.0/15 */
 213             } else if ((addr & 0xe0000000) == 0xe0000000) {
 214                 mask.s_addr = htonl(0xffffff00); /* class C */
 215             } else {
 216                 mask.s_addr = htonl(0xfffffff0); /* multicast/reserved */
 217             }
 218         } else {
 219             if (!inet_aton(buf, &net)) {
 220                 return -1;
 221             }
 222             shift = strtol(vnetwork, &end, 10);
 223             if (*end != '\0') {
 224                 if (!inet_aton(vnetwork, &mask)) {
 225                     return -1;
 226                 }
 227             } else if (shift < 4 || shift > 32) {
 228                 return -1;
 229             } else {
 230                 mask.s_addr = htonl(0xffffffff << (32 - shift));
 231             }
 232         }
 233         net.s_addr &= mask.s_addr;
 234         host.s_addr = net.s_addr | (htonl(0x0202) & ~mask.s_addr);
 235         dhcp.s_addr = net.s_addr | (htonl(0x020f) & ~mask.s_addr);
 236         dns.s_addr  = net.s_addr | (htonl(0x0203) & ~mask.s_addr);
 237     }
 238
 239     if (vhost && !inet_aton(vhost, &host)) {
 240         return -1;
 241     }
 242     if ((host.s_addr & mask.s_addr) != net.s_addr) {
 243         return -1;
 244     }
 245
 246     if (vnameserver && !inet_aton(vnameserver, &dns)) {
 247         return -1;
 248     }
 249     if ((dns.s_addr & mask.s_addr) != net.s_addr ||
 250         dns.s_addr == host.s_addr) {
 251         return -1;
 252     }
 253
 254     if (vdhcp_start && !inet_aton(vdhcp_start, &dhcp)) {
 255         return -1;
 256     }
 257     if ((dhcp.s_addr & mask.s_addr) != net.s_addr ||
 258         dhcp.s_addr == host.s_addr || dhcp.s_addr == dns.s_addr) {
 259         return -1;
 260     }
 261
 262 #ifndef _WIN32
 263     if (vsmbserver && !inet_aton(vsmbserver, &smbsrv)) {
 264         return -1;
 265     }
 266 #endif
 267
 268 #if defined(_WIN32) && (_WIN32_WINNT < 0x0600)
 269     /* No inet_pton helper before Vista... */
 270     if (vprefix6) {
 271         /* Unsupported */
 272         return -1;
 273     }
 274     memset(&ip6_prefix, 0, sizeof(ip6_prefix));
 275     ip6_prefix.s6_addr[0] = 0xfe;
 276     ip6_prefix.s6_addr[1] = 0xc0;
 277 #else
 278     if (!vprefix6) {
 279         vprefix6 = "fec0::";
 280     }
 281     if (!inet_pton(AF_INET6, vprefix6, &ip6_prefix)) {
 282         return -1;
 283     }
 284 #endif
 285
 286     if (!vprefix6_len) {
 287         vprefix6_len = 64;
 288     }
 289     if (vprefix6_len < 0 || vprefix6_len > 126) {
 290         return -1;
 291     }
 292
 293     if (vhost6) {
 294 #if defined(_WIN32) && (_WIN32_WINNT < 0x0600)
 295         return -1;
 296 #else
 297         if (!inet_pton(AF_INET6, vhost6, &ip6_host)) {
 298             return -1;
 299         }
 300         if (!in6_equal_net(&ip6_prefix, &ip6_host, vprefix6_len)) {
 301             return -1;
 302         }
 303 #endif
 304     } else {
 305         ip6_host = ip6_prefix;
 306         ip6_host.s6_addr[15] |= 2;
 307     }
 308
 309     if (vnameserver6) {
 310 #if defined(_WIN32) && (_WIN32_WINNT < 0x0600)
 311         return -1;
 312 #else
 313         if (!inet_pton(AF_INET6, vnameserver6, &ip6_dns)) {
 314             return -1;
 315         }
 316         if (!in6_equal_net(&ip6_prefix, &ip6_dns, vprefix6_len)) {
 317             return -1;
 318         }
 319 #endif
 320     } else {
 321         ip6_dns = ip6_prefix;
 322         ip6_dns.s6_addr[15] |= 3;
 323     }
 324
 325
 326     nc = qemu_new_net_client(&net_slirp_info, peer, model, name);
 327
 328     snprintf(nc->info_str, sizeof(nc->info_str),
 329              "net=%s,restrict=%s", inet_ntoa(net),
 330              restricted ? "on" : "off");
 331
 332     s = DO_UPCAST(SlirpState, nc, nc);
 333
 334     s->slirp = slirp_init(restricted, ipv4, net, mask, host,
 335                           ipv6, ip6_prefix, vprefix6_len, ip6_host,
 336                           vhostname, tftp_export, bootfile, dhcp,
 337                           dns, ip6_dns, dnssearch, s);
 338     QTAILQ_INSERT_TAIL(&slirp_stacks, s, entry);
 339
 340     for (config = slirp_configs; config; config = config->next) {
 341         if (config->flags & SLIRP_CFG_HOSTFWD) {
 342             if (slirp_hostfwd(s, config->str,
 343                               config->flags & SLIRP_CFG_LEGACY) < 0)
 344                 goto error;
 345         } else {
 346             if (slirp_guestfwd(s, config->str,
 347                                config->flags & SLIRP_CFG_LEGACY) < 0)
 348                 goto error;
 349         }
 350     }
 351 #ifndef _WIN32
 352     if (!smb_export) {
 353         smb_export = legacy_smb_export;
 354     }
 355     if (smb_export) {
 356         if (slirp_smb(s, smb_export, smbsrv) < 0)
 357             goto error;
 358     }
 359 #endif
 360
 361     s->exit_notifier.notify = slirp_smb_exit;
 362     qemu_add_exit_notifier(&s->exit_notifier);
 363     return 0;
 364
 365 error:
 366     qemu_del_net_client(nc);
 367     return -1;
 368 }
 369
 370 static SlirpState *slirp_lookup(Monitor *mon, const char *vlan,
 371                                 const char *stack)
 372 {
 373
 374     if (vlan) {
 375         NetClientState *nc;
 376         nc = net_hub_find_client_by_name(strtol(vlan, NULL, 0), stack);
 377         if (!nc) {
 378             monitor_printf(mon, "unrecognized (vlan-id, stackname) pair\n");
 379             return NULL;
 380         }
 381         if (strcmp(nc->model, "user")) {
 382             monitor_printf(mon, "invalid device specified\n");
 383             return NULL;
 384         }
 385         return DO_UPCAST(SlirpState, nc, nc);
 386     } else {
 387         if (QTAILQ_EMPTY(&slirp_stacks)) {
 388             monitor_printf(mon, "user mode network stack not in use\n");
 389             return NULL;
 390         }
 391         return QTAILQ_FIRST(&slirp_stacks);
 392     }
 393 }
 394
 395 void hmp_hostfwd_remove(Monitor *mon, const QDict *qdict)
 396 {
 397     struct in_addr host_addr = { .s_addr = INADDR_ANY };
 398     int host_port;
 399     char buf[256];
 400     const char *src_str, *p;
 401     SlirpState *s;
 402     int is_udp = 0;
 403     int err;
 404     const char *arg1 = qdict_get_str(qdict, "arg1");
 405     const char *arg2 = qdict_get_try_str(qdict, "arg2");
 406     const char *arg3 = qdict_get_try_str(qdict, "arg3");
 407
 408     if (arg2) {
 409         s = slirp_lookup(mon, arg1, arg2);
 410         src_str = arg3;
 411     } else {
 412         s = slirp_lookup(mon, NULL, NULL);
 413         src_str = arg1;
 414     }
 415     if (!s) {
 416         return;
 417     }
 418
 419     p = src_str;
 420     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 421         goto fail_syntax;
 422     }
 423
 424     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
 425         is_udp = 0;
 426     } else if (!strcmp(buf, "udp")) {
 427         is_udp = 1;
 428     } else {
 429         goto fail_syntax;
 430     }
 431
 432     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 433         goto fail_syntax;
 434     }
 435     if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
 436         goto fail_syntax;
 437     }
 438
 439     host_port = atoi(p);
 440
 441     err = slirp_remove_hostfwd(s->slirp, is_udp, host_addr, host_port);
 442
 443     monitor_printf(mon, "host forwarding rule for %s %s\n", src_str,
 444                    err ? "not found" : "removed");
 445     return;
 446
 447  fail_syntax:
 448     monitor_printf(mon, "invalid format\n");
 449 }
 450
 451 static int slirp_hostfwd(SlirpState *s, const char *redir_str,
 452                          int legacy_format)
 453 {
 454     struct in_addr host_addr = { .s_addr = INADDR_ANY };
 455     struct in_addr guest_addr = { .s_addr = 0 };
 456     int host_port, guest_port;
 457     const char *p;
 458     char buf[256];
 459     int is_udp;
 460     char *end;
 461
 462     p = redir_str;
 463     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 464         goto fail_syntax;
 465     }
 466     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
 467         is_udp = 0;
 468     } else if (!strcmp(buf, "udp")) {
 469         is_udp = 1;
 470     } else {
 471         goto fail_syntax;
 472     }
 473
 474     if (!legacy_format) {
 475         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 476             goto fail_syntax;
 477         }
 478         if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
 479             goto fail_syntax;
 480         }
 481     }
 482
 483     if (get_str_sep(buf, sizeof(buf), &p, legacy_format ? ':' : '-') < 0) {
 484         goto fail_syntax;
 485     }
 486     host_port = strtol(buf, &end, 0);
 487     if (*end != '\0' || host_port < 1 || host_port > 65535) {
 488         goto fail_syntax;
 489     }
 490
 491     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 492         goto fail_syntax;
 493     }
 494     if (buf[0] != '\0' && !inet_aton(buf, &guest_addr)) {
 495         goto fail_syntax;
 496     }
 497
 498     guest_port = strtol(p, &end, 0);
 499     if (*end != '\0' || guest_port < 1 || guest_port > 65535) {
 500         goto fail_syntax;
 501     }
 502
 503     if (slirp_add_hostfwd(s->slirp, is_udp, host_addr, host_port, guest_addr,
 504                           guest_port) < 0) {
 505         error_report("could not set up host forwarding rule '%s'",
 506                      redir_str);
 507         return -1;
 508     }
 509     return 0;
 510
 511  fail_syntax:
 512     error_report("invalid host forwarding rule '%s'", redir_str);
 513     return -1;
 514 }
 515
 516 void hmp_hostfwd_add(Monitor *mon, const QDict *qdict)
 517 {
 518     const char *redir_str;
 519     SlirpState *s;
 520     const char *arg1 = qdict_get_str(qdict, "arg1");
 521     const char *arg2 = qdict_get_try_str(qdict, "arg2");
 522     const char *arg3 = qdict_get_try_str(qdict, "arg3");
 523
 524     if (arg2) {
 525         s = slirp_lookup(mon, arg1, arg2);
 526         redir_str = arg3;
 527     } else {
 528         s = slirp_lookup(mon, NULL, NULL);
 529         redir_str = arg1;
 530     }
 531     if (s) {
 532         slirp_hostfwd(s, redir_str, 0);
 533     }
 534
 535 }
 536
 537 int net_slirp_redir(const char *redir_str)
 538 {
 539     struct slirp_config_str *config;
 540
 541     if (QTAILQ_EMPTY(&slirp_stacks)) {
 542         config = g_malloc(sizeof(*config));
 543         pstrcpy(config->str, sizeof(config->str), redir_str);
 544         config->flags = SLIRP_CFG_HOSTFWD | SLIRP_CFG_LEGACY;
 545         config->next = slirp_configs;
 546         slirp_configs = config;
 547         return 0;
 548     }
 549
 550     return slirp_hostfwd(QTAILQ_FIRST(&slirp_stacks), redir_str, 1);
 551 }
 552
 553 #ifndef _WIN32
 554
 555 /* automatic user mode samba server configuration */
 556 static void slirp_smb_cleanup(SlirpState *s)
 557 {
 558     char cmd[128];
 559     int ret;
 560
 561     if (s->smb_dir[0] != '\0') {
 562         snprintf(cmd, sizeof(cmd), "rm -rf %s", s->smb_dir);
 563         ret = system(cmd);
 564         if (ret == -1 || !WIFEXITED(ret)) {
 565             error_report("'%s' failed.", cmd);
 566         } else if (WEXITSTATUS(ret)) {
 567             error_report("'%s' failed. Error code: %d",
 568                          cmd, WEXITSTATUS(ret));
 569         }
 570         s->smb_dir[0] = '\0';
 571     }
 572 }
 573
 574 static int slirp_smb(SlirpState* s, const char *exported_dir,
 575                      struct in_addr vserver_addr)
 576 {
 577     char smb_conf[128];
 578     char smb_cmdline[128];
 579     struct passwd *passwd;
 580     FILE *f;
 581
 582     passwd = getpwuid(geteuid());
 583     if (!passwd) {
 584         error_report("failed to retrieve user name");
 585         return -1;
 586     }
 587
 588     if (access(CONFIG_SMBD_COMMAND, F_OK)) {
 589         error_report("could not find '%s', please install it",
 590                      CONFIG_SMBD_COMMAND);
 591         return -1;
 592     }
 593
 594     if (access(exported_dir, R_OK | X_OK)) {
 595         error_report("error accessing shared directory '%s': %s",
 596                      exported_dir, strerror(errno));
 597         return -1;
 598     }
 599
 600     snprintf(s->smb_dir, sizeof(s->smb_dir), "/tmp/qemu-smb.XXXXXX");
 601     if (!mkdtemp(s->smb_dir)) {
 602         error_report("could not create samba server dir '%s'", s->smb_dir);
 603         s->smb_dir[0] = 0;
 604         return -1;
 605     }
 606     snprintf(smb_conf, sizeof(smb_conf), "%s/%s", s->smb_dir, "smb.conf");
 607
 608     f = fopen(smb_conf, "w");
 609     if (!f) {
 610         slirp_smb_cleanup(s);
 611         error_report("could not create samba server configuration file '%s'",
 612                      smb_conf);
 613         return -1;
 614     }
 615     fprintf(f,
 616             "[global]\n"
 617             "private dir=%s\n"
 618             "interfaces=127.0.0.1\n"
 619             "bind interfaces only=yes\n"
 620             "pid directory=%s\n"
 621             "lock directory=%s\n"
 622             "state directory=%s\n"
 623             "cache directory=%s\n"
 624             "ncalrpc dir=%s/ncalrpc\n"
 625             "log file=%s/log.smbd\n"
 626             "smb passwd file=%s/smbpasswd\n"
 627             "security = user\n"
 628             "map to guest = Bad User\n"
 629             "load printers = no\n"
 630             "printing = bsd\n"
 631             "disable spoolss = yes\n"
 632             "usershare max shares = 0\n"
 633             "[qemu]\n"
 634             "path=%s\n"
 635             "read only=no\n"
 636             "guest ok=yes\n"
 637             "force user=%s\n",
 638             s->smb_dir,
 639             s->smb_dir,
 640             s->smb_dir,
 641             s->smb_dir,
 642             s->smb_dir,
 643             s->smb_dir,
 644             s->smb_dir,
 645             s->smb_dir,
 646             exported_dir,
 647             passwd->pw_name
 648             );
 649     fclose(f);
 650
 651     snprintf(smb_cmdline, sizeof(smb_cmdline), "%s -l %s -s %s",
 652              CONFIG_SMBD_COMMAND, s->smb_dir, smb_conf);
 653
 654     if (slirp_add_exec(s->slirp, 0, smb_cmdline, &vserver_addr, 139) < 0 ||
 655         slirp_add_exec(s->slirp, 0, smb_cmdline, &vserver_addr, 445) < 0) {
 656         slirp_smb_cleanup(s);
 657         error_report("conflicting/invalid smbserver address");
 658         return -1;
 659     }
 660     return 0;
 661 }
 662
 663 /* automatic user mode samba server configuration (legacy interface) */
 664 int net_slirp_smb(const char *exported_dir)
 665 {
 666     struct in_addr vserver_addr = { .s_addr = 0 };
 667
 668     if (legacy_smb_export) {
 669         fprintf(stderr, "-smb given twice\n");
 670         return -1;
 671     }
 672     legacy_smb_export = exported_dir;
 673     if (!QTAILQ_EMPTY(&slirp_stacks)) {
 674         return slirp_smb(QTAILQ_FIRST(&slirp_stacks), exported_dir,
 675                          vserver_addr);
 676     }
 677     return 0;
 678 }
 679
 680 #endif /* !defined(_WIN32) */
 681
 682 struct GuestFwd {
 683     CharDriverState *hd;
 684     struct in_addr server;
 685     int port;
 686     Slirp *slirp;
 687 };
 688
 689 static int guestfwd_can_read(void *opaque)
 690 {
 691     struct GuestFwd *fwd = opaque;
 692     return slirp_socket_can_recv(fwd->slirp, fwd->server, fwd->port);
 693 }
 694
 695 static void guestfwd_read(void *opaque, const uint8_t *buf, int size)
 696 {
 697     struct GuestFwd *fwd = opaque;
 698     slirp_socket_recv(fwd->slirp, fwd->server, fwd->port, buf, size);
 699 }
 700
 701 static int slirp_guestfwd(SlirpState *s, const char *config_str,
 702                           int legacy_format)
 703 {
 704     struct in_addr server = { .s_addr = 0 };
 705     struct GuestFwd *fwd;
 706     const char *p;
 707     char buf[128];
 708     char *end;
 709     int port;
 710
 711     p = config_str;
 712     if (legacy_format) {
 713         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 714             goto fail_syntax;
 715         }
 716     } else {
 717         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 718             goto fail_syntax;
 719         }
 720         if (strcmp(buf, "tcp") && buf[0] != '\0') {
 721             goto fail_syntax;
 722         }
 723         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 724             goto fail_syntax;
 725         }
 726         if (buf[0] != '\0' && !inet_aton(buf, &server)) {
 727             goto fail_syntax;
 728         }
 729         if (get_str_sep(buf, sizeof(buf), &p, '-') < 0) {
 730             goto fail_syntax;
 731         }
 732     }
 733     port = strtol(buf, &end, 10);
 734     if (*end != '\0' || port < 1 || port > 65535) {
 735         goto fail_syntax;
 736     }
 737
 738     snprintf(buf, sizeof(buf), "guestfwd.tcp.%d", port);
 739
 740     if ((strlen(p) > 4) && !strncmp(p, "cmd:", 4)) {
 741         if (slirp_add_exec(s->slirp, 0, &p[4], &server, port) < 0) {
 742             error_report("conflicting/invalid host:port in guest forwarding "
 743                          "rule '%s'", config_str);
 744             return -1;
 745         }
 746     } else {
 747         fwd = g_new(struct GuestFwd, 1);
 748         fwd->hd = qemu_chr_new(buf, p, NULL);
 749         if (!fwd->hd) {
 750             error_report("could not open guest forwarding device '%s'", buf);
 751             g_free(fwd);
 752             return -1;
 753         }
 754
 755         if (slirp_add_exec(s->slirp, 3, fwd->hd, &server, port) < 0) {
 756             error_report("conflicting/invalid host:port in guest forwarding "
 757                          "rule '%s'", config_str);
 758             g_free(fwd);
 759             return -1;
 760         }
 761         fwd->server = server;
 762         fwd->port = port;
 763         fwd->slirp = s->slirp;
 764
 765         qemu_chr_fe_claim_no_fail(fwd->hd);
 766         qemu_chr_add_handlers(fwd->hd, guestfwd_can_read, guestfwd_read,
 767                               NULL, fwd);
 768     }
 769     return 0;
 770
 771  fail_syntax:
 772     error_report("invalid guest forwarding rule '%s'", config_str);
 773     return -1;
 774 }
 775
 776 void hmp_info_usernet(Monitor *mon, const QDict *qdict)
 777 {
 778     SlirpState *s;
 779
 780     QTAILQ_FOREACH(s, &slirp_stacks, entry) {
 781         int id;
 782         bool got_vlan_id = net_hub_id_for_client(&s->nc, &id) == 0;
 783         monitor_printf(mon, "VLAN %d (%s):\n",
 784                        got_vlan_id ? id : -1,
 785                        s->nc.name);
 786         slirp_connection_info(s->slirp, mon);
 787     }
 788 }
 789
 790 static void
 791 net_init_slirp_configs(const StringList *fwd, int flags)
 792 {
 793     while (fwd) {
 794         struct slirp_config_str *config;
 795
 796         config = g_malloc0(sizeof(*config));
 797         pstrcpy(config->str, sizeof(config->str), fwd->value->str);
 798         config->flags = flags;
 799         config->next = slirp_configs;
 800         slirp_configs = config;
 801
 802         fwd = fwd->next;
 803     }
 804 }
 805
 806 static const char **slirp_dnssearch(const StringList *dnsname)
 807 {
 808     const StringList *c = dnsname;
 809     size_t i = 0, num_opts = 0;
 810     const char **ret;
 811
 812     while (c) {
 813         num_opts++;
 814         c = c->next;
 815     }
 816
 817     if (num_opts == 0) {
 818         return NULL;
 819     }
 820
 821     ret = g_malloc((num_opts + 1) * sizeof(*ret));
 822     c = dnsname;
 823     while (c) {
 824         ret[i++] = c->value->str;
 825         c = c->next;
 826     }
 827     ret[i] = NULL;
 828     return ret;
 829 }
 830
 831 int net_init_slirp(const NetClientOptions *opts, const char *name,
 832                    NetClientState *peer, Error **errp)
 833 {
 834     /* FIXME error_setg(errp, ...) on failure */
 835     struct slirp_config_str *config;
 836     char *vnet;
 837     int ret;
 838     const NetdevUserOptions *user;
 839     const char **dnssearch;
 840     bool ipv4 = true, ipv6 = true;
 841
 842     assert(opts->type == NET_CLIENT_OPTIONS_KIND_USER);
 843     user = opts->u.user.data;
 844
 845     if ((user->has_ipv6 && user->ipv6 && !user->has_ipv4) ||
 846         (user->has_ipv4 && !user->ipv4)) {
 847         ipv4 = 0;
 848     }
 849     if ((user->has_ipv4 && user->ipv4 && !user->has_ipv6) ||
 850         (user->has_ipv6 && !user->ipv6)) {
 851         ipv6 = 0;
 852     }
 853
 854     vnet = user->has_net ? g_strdup(user->net) :
 855            user->has_ip  ? g_strdup_printf("%s/24", user->ip) :
 856            NULL;
 857
 858     dnssearch = slirp_dnssearch(user->dnssearch);
 859
 860     /* all optional fields are initialized to "all bits zero" */
 861
 862     net_init_slirp_configs(user->hostfwd, SLIRP_CFG_HOSTFWD);
 863     net_init_slirp_configs(user->guestfwd, 0);
 864
 865     ret = net_slirp_init(peer, "user", name, user->q_restrict,
 866                          ipv4, vnet, user->host,
 867                          ipv6, user->ipv6_prefix, user->ipv6_prefixlen,
 868                          user->ipv6_host, user->hostname, user->tftp,
 869                          user->bootfile, user->dhcpstart,
 870                          user->dns, user->ipv6_dns, user->smb,
 871                          user->smbserver, dnssearch);
 872
 873     while (slirp_configs) {
 874         config = slirp_configs;
 875         slirp_configs = config->next;
 876         g_free(config);
 877     }
 878
 879     g_free(vnet);
 880     g_free(dnssearch);
 881
 882     return ret;
 883 }
 884
 885 int net_slirp_parse_legacy(QemuOptsList *opts_list, const char *optarg, int *ret)
 886 {
 887     if (strcmp(opts_list->name, "net") != 0 ||
 888         strncmp(optarg, "channel,", strlen("channel,")) != 0) {
 889         return 0;
 890     }
 891
 892     error_report("The '-net channel' option is deprecated. "
 893                  "Please use '-netdev user,guestfwd=...' instead.");
 894
 895     /* handle legacy -net channel,port:chr */
 896     optarg += strlen("channel,");
 897
 898     if (QTAILQ_EMPTY(&slirp_stacks)) {
 899         struct slirp_config_str *config;
 900
 901         config = g_malloc(sizeof(*config));
 902         pstrcpy(config->str, sizeof(config->str), optarg);
 903         config->flags = SLIRP_CFG_LEGACY;
 904         config->next = slirp_configs;
 905         slirp_configs = config;
 906         *ret = 0;
 907     } else {
 908         *ret = slirp_guestfwd(QTAILQ_FIRST(&slirp_stacks), optarg, 1);
 909     }
 910
 911     return 1;
 912 }
 913