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
  25 #include "qemu/osdep.h"
  26 #include "net/slirp.h"
  27
  28
  29 #ifndef _WIN32
  30 #include <pwd.h>
  31 #include <sys/wait.h>
  32 #endif
  33 #include "net/net.h"
  34 #include "clients.h"
  35 #include "hub.h"
  36 #include "monitor/monitor.h"
  37 #include "qemu/error-report.h"
  38 #include "qemu/sockets.h"
  39 #include "slirp/libslirp.h"
  40 #include "slirp/ip6.h"
  41 #include "chardev/char-fe.h"
  42 #include "sysemu/sysemu.h"
  43 #include "qemu/cutils.h"
  44 #include "qapi/error.h"
  45 #include "qapi/qmp/qdict.h"
  46
  47 static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
  48 {
  49     const char *p, *p1;
  50     int len;
  51     p = *pp;
  52     p1 = strchr(p, sep);
  53     if (!p1)
  54         return -1;
  55     len = p1 - p;
  56     p1++;
  57     if (buf_size > 0) {
  58         if (len > buf_size - 1)
  59             len = buf_size - 1;
  60         memcpy(buf, p, len);
  61         buf[len] = '\0';
  62     }
  63     *pp = p1;
  64     return 0;
  65 }
  66
  67 /* slirp network adapter */
  68
  69 #define SLIRP_CFG_HOSTFWD 1
  70
  71 struct slirp_config_str {
  72     struct slirp_config_str *next;
  73     int flags;
  74     char str[1024];
  75 };
  76
  77 typedef struct SlirpState {
  78     NetClientState nc;
  79     QTAILQ_ENTRY(SlirpState) entry;
  80     Slirp *slirp;
  81     Notifier exit_notifier;
  82 #ifndef _WIN32
  83     gchar *smb_dir;
  84 #endif
  85 } SlirpState;
  86
  87 static struct slirp_config_str *slirp_configs;
  88 static QTAILQ_HEAD(slirp_stacks, SlirpState) slirp_stacks =
  89     QTAILQ_HEAD_INITIALIZER(slirp_stacks);
  90
  91 static int slirp_hostfwd(SlirpState *s, const char *redir_str, Error **errp);
  92 static int slirp_guestfwd(SlirpState *s, const char *config_str, Error **errp);
  93
  94 #ifndef _WIN32
  95 static int slirp_smb(SlirpState *s, const char *exported_dir,
  96                      struct in_addr vserver_addr, Error **errp);
  97 static void slirp_smb_cleanup(SlirpState *s);
  98 #else
  99 static inline void slirp_smb_cleanup(SlirpState *s) { }
 100 #endif
 101
 102 void slirp_output(void *opaque, const uint8_t *pkt, int pkt_len)
 103 {
 104     SlirpState *s = opaque;
 105
 106     qemu_send_packet(&s->nc, pkt, pkt_len);
 107 }
 108
 109 static ssize_t net_slirp_receive(NetClientState *nc, const uint8_t *buf, size_t size)
 110 {
 111     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
 112
 113     slirp_input(s->slirp, buf, size);
 114
 115     return size;
 116 }
 117
 118 static void slirp_smb_exit(Notifier *n, void *data)
 119 {
 120     SlirpState *s = container_of(n, SlirpState, exit_notifier);
 121     slirp_smb_cleanup(s);
 122 }
 123
 124 static void net_slirp_cleanup(NetClientState *nc)
 125 {
 126     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
 127
 128     slirp_cleanup(s->slirp);
 129     if (s->exit_notifier.notify) {
 130         qemu_remove_exit_notifier(&s->exit_notifier);
 131     }
 132     slirp_smb_cleanup(s);
 133     QTAILQ_REMOVE(&slirp_stacks, s, entry);
 134 }
 135
 136 static NetClientInfo net_slirp_info = {
 137     .type = NET_CLIENT_DRIVER_USER,
 138     .size = sizeof(SlirpState),
 139     .receive = net_slirp_receive,
 140     .cleanup = net_slirp_cleanup,
 141 };
 142
 143 static int net_slirp_init(NetClientState *peer, const char *model,
 144                           const char *name, int restricted,
 145                           bool ipv4, const char *vnetwork, const char *vhost,
 146                           bool ipv6, const char *vprefix6, int vprefix6_len,
 147                           const char *vhost6,
 148                           const char *vhostname, const char *tftp_export,
 149                           const char *bootfile, const char *vdhcp_start,
 150                           const char *vnameserver, const char *vnameserver6,
 151                           const char *smb_export, const char *vsmbserver,
 152                           const char **dnssearch, const char *vdomainname,
 153                           Error **errp)
 154 {
 155     /* default settings according to historic slirp */
 156     struct in_addr net  = { .s_addr = htonl(0x0a000200) }; /* 10.0.2.0 */
 157     struct in_addr mask = { .s_addr = htonl(0xffffff00) }; /* 255.255.255.0 */
 158     struct in_addr host = { .s_addr = htonl(0x0a000202) }; /* 10.0.2.2 */
 159     struct in_addr dhcp = { .s_addr = htonl(0x0a00020f) }; /* 10.0.2.15 */
 160     struct in_addr dns  = { .s_addr = htonl(0x0a000203) }; /* 10.0.2.3 */
 161     struct in6_addr ip6_prefix;
 162     struct in6_addr ip6_host;
 163     struct in6_addr ip6_dns;
 164 #ifndef _WIN32
 165     struct in_addr smbsrv = { .s_addr = 0 };
 166 #endif
 167     NetClientState *nc;
 168     SlirpState *s;
 169     char buf[20];
 170     uint32_t addr;
 171     int shift;
 172     char *end;
 173     struct slirp_config_str *config;
 174
 175     if (!ipv4 && (vnetwork || vhost || vnameserver)) {
 176         error_setg(errp, "IPv4 disabled but netmask/host/dns provided");
 177         return -1;
 178     }
 179
 180     if (!ipv6 && (vprefix6 || vhost6 || vnameserver6)) {
 181         error_setg(errp, "IPv6 disabled but prefix/host6/dns6 provided");
 182         return -1;
 183     }
 184
 185     if (!ipv4 && !ipv6) {
 186         /* It doesn't make sense to disable both */
 187         error_setg(errp, "IPv4 and IPv6 disabled");
 188         return -1;
 189     }
 190
 191     if (vnetwork) {
 192         if (get_str_sep(buf, sizeof(buf), &vnetwork, '/') < 0) {
 193             if (!inet_aton(vnetwork, &net)) {
 194                 error_setg(errp, "Failed to parse netmask");
 195                 return -1;
 196             }
 197             addr = ntohl(net.s_addr);
 198             if (!(addr & 0x80000000)) {
 199                 mask.s_addr = htonl(0xff000000); /* class A */
 200             } else if ((addr & 0xfff00000) == 0xac100000) {
 201                 mask.s_addr = htonl(0xfff00000); /* priv. 172.16.0.0/12 */
 202             } else if ((addr & 0xc0000000) == 0x80000000) {
 203                 mask.s_addr = htonl(0xffff0000); /* class B */
 204             } else if ((addr & 0xffff0000) == 0xc0a80000) {
 205                 mask.s_addr = htonl(0xffff0000); /* priv. 192.168.0.0/16 */
 206             } else if ((addr & 0xffff0000) == 0xc6120000) {
 207                 mask.s_addr = htonl(0xfffe0000); /* tests 198.18.0.0/15 */
 208             } else if ((addr & 0xe0000000) == 0xe0000000) {
 209                 mask.s_addr = htonl(0xffffff00); /* class C */
 210             } else {
 211                 mask.s_addr = htonl(0xfffffff0); /* multicast/reserved */
 212             }
 213         } else {
 214             if (!inet_aton(buf, &net)) {
 215                 error_setg(errp, "Failed to parse netmask");
 216                 return -1;
 217             }
 218             shift = strtol(vnetwork, &end, 10);
 219             if (*end != '\0') {
 220                 if (!inet_aton(vnetwork, &mask)) {
 221                     error_setg(errp,
 222                                "Failed to parse netmask (trailing chars)");
 223                     return -1;
 224                 }
 225             } else if (shift < 4 || shift > 32) {
 226                 error_setg(errp,
 227                            "Invalid netmask provided (must be in range 4-32)");
 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         error_setg(errp, "Failed to parse host");
 241         return -1;
 242     }
 243     if ((host.s_addr & mask.s_addr) != net.s_addr) {
 244         error_setg(errp, "Host doesn't belong to network");
 245         return -1;
 246     }
 247
 248     if (vnameserver && !inet_aton(vnameserver, &dns)) {
 249         error_setg(errp, "Failed to parse DNS");
 250         return -1;
 251     }
 252     if ((dns.s_addr & mask.s_addr) != net.s_addr) {
 253         error_setg(errp, "DNS doesn't belong to network");
 254         return -1;
 255     }
 256     if (dns.s_addr == host.s_addr) {
 257         error_setg(errp, "DNS must be different from host");
 258         return -1;
 259     }
 260
 261     if (vdhcp_start && !inet_aton(vdhcp_start, &dhcp)) {
 262         error_setg(errp, "Failed to parse DHCP start address");
 263         return -1;
 264     }
 265     if ((dhcp.s_addr & mask.s_addr) != net.s_addr) {
 266         error_setg(errp, "DHCP doesn't belong to network");
 267         return -1;
 268     }
 269     if (dhcp.s_addr == host.s_addr || dhcp.s_addr == dns.s_addr) {
 270         error_setg(errp, "DNS must be different from host and DNS");
 271         return -1;
 272     }
 273
 274 #ifndef _WIN32
 275     if (vsmbserver && !inet_aton(vsmbserver, &smbsrv)) {
 276         error_setg(errp, "Failed to parse SMB address");
 277         return -1;
 278     }
 279 #endif
 280
 281 #if defined(_WIN32) && (_WIN32_WINNT < 0x0600)
 282     /* No inet_pton helper before Vista... */
 283     if (vprefix6) {
 284         /* Unsupported */
 285         error_setg(errp, "IPv6 prefix not supported");
 286         return -1;
 287     }
 288     memset(&ip6_prefix, 0, sizeof(ip6_prefix));
 289     ip6_prefix.s6_addr[0] = 0xfe;
 290     ip6_prefix.s6_addr[1] = 0xc0;
 291 #else
 292     if (!vprefix6) {
 293         vprefix6 = "fec0::";
 294     }
 295     if (!inet_pton(AF_INET6, vprefix6, &ip6_prefix)) {
 296         error_setg(errp, "Failed to parse IPv6 prefix");
 297         return -1;
 298     }
 299 #endif
 300
 301     if (!vprefix6_len) {
 302         vprefix6_len = 64;
 303     }
 304     if (vprefix6_len < 0 || vprefix6_len > 126) {
 305         error_setg(errp,
 306                    "Invalid prefix provided (prefix len must be in range 0-126");
 307         return -1;
 308     }
 309
 310     if (vhost6) {
 311 #if defined(_WIN32) && (_WIN32_WINNT < 0x0600)
 312         error_setg(errp, "IPv6 host not supported");
 313         return -1;
 314 #else
 315         if (!inet_pton(AF_INET6, vhost6, &ip6_host)) {
 316             error_setg(errp, "Failed to parse IPv6 host");
 317             return -1;
 318         }
 319         if (!in6_equal_net(&ip6_prefix, &ip6_host, vprefix6_len)) {
 320             error_setg(errp, "IPv6 Host doesn't belong to network");
 321             return -1;
 322         }
 323 #endif
 324     } else {
 325         ip6_host = ip6_prefix;
 326         ip6_host.s6_addr[15] |= 2;
 327     }
 328
 329     if (vnameserver6) {
 330 #if defined(_WIN32) && (_WIN32_WINNT < 0x0600)
 331         error_setg(errp, "IPv6 DNS not supported");
 332         return -1;
 333 #else
 334         if (!inet_pton(AF_INET6, vnameserver6, &ip6_dns)) {
 335             error_setg(errp, "Failed to parse IPv6 DNS");
 336             return -1;
 337         }
 338         if (!in6_equal_net(&ip6_prefix, &ip6_dns, vprefix6_len)) {
 339             error_setg(errp, "IPv6 DNS doesn't belong to network");
 340             return -1;
 341         }
 342 #endif
 343     } else {
 344         ip6_dns = ip6_prefix;
 345         ip6_dns.s6_addr[15] |= 3;
 346     }
 347
 348     if (vdomainname && !*vdomainname) {
 349         error_setg(errp, "'domainname' parameter cannot be empty");
 350         return -1;
 351     }
 352
 353
 354     nc = qemu_new_net_client(&net_slirp_info, peer, model, name);
 355
 356     snprintf(nc->info_str, sizeof(nc->info_str),
 357              "net=%s,restrict=%s", inet_ntoa(net),
 358              restricted ? "on" : "off");
 359
 360     s = DO_UPCAST(SlirpState, nc, nc);
 361
 362     s->slirp = slirp_init(restricted, ipv4, net, mask, host,
 363                           ipv6, ip6_prefix, vprefix6_len, ip6_host,
 364                           vhostname, tftp_export, bootfile, dhcp,
 365                           dns, ip6_dns, dnssearch, vdomainname, s);
 366     QTAILQ_INSERT_TAIL(&slirp_stacks, s, entry);
 367
 368     for (config = slirp_configs; config; config = config->next) {
 369         if (config->flags & SLIRP_CFG_HOSTFWD) {
 370             if (slirp_hostfwd(s, config->str, errp) < 0) {
 371                 goto error;
 372             }
 373         } else {
 374             if (slirp_guestfwd(s, config->str, errp) < 0) {
 375                 goto error;
 376             }
 377         }
 378     }
 379 #ifndef _WIN32
 380     if (smb_export) {
 381         if (slirp_smb(s, smb_export, smbsrv, errp) < 0) {
 382             goto error;
 383         }
 384     }
 385 #endif
 386
 387     s->exit_notifier.notify = slirp_smb_exit;
 388     qemu_add_exit_notifier(&s->exit_notifier);
 389     return 0;
 390
 391 error:
 392     qemu_del_net_client(nc);
 393     return -1;
 394 }
 395
 396 static SlirpState *slirp_lookup(Monitor *mon, const char *hub_id,
 397                                 const char *name)
 398 {
 399     if (name) {
 400         NetClientState *nc;
 401         if (hub_id) {
 402             nc = net_hub_find_client_by_name(strtol(hub_id, NULL, 0), name);
 403             if (!nc) {
 404                 monitor_printf(mon, "unrecognized (hub-id, stackname) pair\n");
 405                 return NULL;
 406             }
 407         } else {
 408             nc = qemu_find_netdev(name);
 409             if (!nc) {
 410                 monitor_printf(mon, "unrecognized netdev id '%s'\n", name);
 411                 return NULL;
 412             }
 413         }
 414         if (strcmp(nc->model, "user")) {
 415             monitor_printf(mon, "invalid device specified\n");
 416             return NULL;
 417         }
 418         return DO_UPCAST(SlirpState, nc, nc);
 419     } else {
 420         if (QTAILQ_EMPTY(&slirp_stacks)) {
 421             monitor_printf(mon, "user mode network stack not in use\n");
 422             return NULL;
 423         }
 424         return QTAILQ_FIRST(&slirp_stacks);
 425     }
 426 }
 427
 428 void hmp_hostfwd_remove(Monitor *mon, const QDict *qdict)
 429 {
 430     struct in_addr host_addr = { .s_addr = INADDR_ANY };
 431     int host_port;
 432     char buf[256];
 433     const char *src_str, *p;
 434     SlirpState *s;
 435     int is_udp = 0;
 436     int err;
 437     const char *arg1 = qdict_get_str(qdict, "arg1");
 438     const char *arg2 = qdict_get_try_str(qdict, "arg2");
 439     const char *arg3 = qdict_get_try_str(qdict, "arg3");
 440
 441     if (arg3) {
 442         s = slirp_lookup(mon, arg1, arg2);
 443         src_str = arg3;
 444     } else if (arg2) {
 445         s = slirp_lookup(mon, NULL, arg1);
 446         src_str = arg2;
 447     } else {
 448         s = slirp_lookup(mon, NULL, NULL);
 449         src_str = arg1;
 450     }
 451     if (!s) {
 452         return;
 453     }
 454
 455     p = src_str;
 456     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 457         goto fail_syntax;
 458     }
 459
 460     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
 461         is_udp = 0;
 462     } else if (!strcmp(buf, "udp")) {
 463         is_udp = 1;
 464     } else {
 465         goto fail_syntax;
 466     }
 467
 468     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 469         goto fail_syntax;
 470     }
 471     if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
 472         goto fail_syntax;
 473     }
 474
 475     if (qemu_strtoi(p, NULL, 10, &host_port)) {
 476         goto fail_syntax;
 477     }
 478
 479     err = slirp_remove_hostfwd(s->slirp, is_udp, host_addr, host_port);
 480
 481     monitor_printf(mon, "host forwarding rule for %s %s\n", src_str,
 482                    err ? "not found" : "removed");
 483     return;
 484
 485  fail_syntax:
 486     monitor_printf(mon, "invalid format\n");
 487 }
 488
 489 static int slirp_hostfwd(SlirpState *s, const char *redir_str, Error **errp)
 490 {
 491     struct in_addr host_addr = { .s_addr = INADDR_ANY };
 492     struct in_addr guest_addr = { .s_addr = 0 };
 493     int host_port, guest_port;
 494     const char *p;
 495     char buf[256];
 496     int is_udp;
 497     char *end;
 498     const char *fail_reason = "Unknown reason";
 499
 500     p = redir_str;
 501     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 502         fail_reason = "No : separators";
 503         goto fail_syntax;
 504     }
 505     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
 506         is_udp = 0;
 507     } else if (!strcmp(buf, "udp")) {
 508         is_udp = 1;
 509     } else {
 510         fail_reason = "Bad protocol name";
 511         goto fail_syntax;
 512     }
 513
 514     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 515         fail_reason = "Missing : separator";
 516         goto fail_syntax;
 517     }
 518     if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
 519         fail_reason = "Bad host address";
 520         goto fail_syntax;
 521     }
 522
 523     if (get_str_sep(buf, sizeof(buf), &p, '-') < 0) {
 524         fail_reason = "Bad host port separator";
 525         goto fail_syntax;
 526     }
 527     host_port = strtol(buf, &end, 0);
 528     if (*end != '\0' || host_port < 0 || host_port > 65535) {
 529         fail_reason = "Bad host port";
 530         goto fail_syntax;
 531     }
 532
 533     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 534         fail_reason = "Missing guest address";
 535         goto fail_syntax;
 536     }
 537     if (buf[0] != '\0' && !inet_aton(buf, &guest_addr)) {
 538         fail_reason = "Bad guest address";
 539         goto fail_syntax;
 540     }
 541
 542     guest_port = strtol(p, &end, 0);
 543     if (*end != '\0' || guest_port < 1 || guest_port > 65535) {
 544         fail_reason = "Bad guest port";
 545         goto fail_syntax;
 546     }
 547
 548     if (slirp_add_hostfwd(s->slirp, is_udp, host_addr, host_port, guest_addr,
 549                           guest_port) < 0) {
 550         error_setg(errp, "Could not set up host forwarding rule '%s'",
 551                    redir_str);
 552         return -1;
 553     }
 554     return 0;
 555
 556  fail_syntax:
 557     error_setg(errp, "Invalid host forwarding rule '%s' (%s)", redir_str,
 558                fail_reason);
 559     return -1;
 560 }
 561
 562 void hmp_hostfwd_add(Monitor *mon, const QDict *qdict)
 563 {
 564     const char *redir_str;
 565     SlirpState *s;
 566     const char *arg1 = qdict_get_str(qdict, "arg1");
 567     const char *arg2 = qdict_get_try_str(qdict, "arg2");
 568     const char *arg3 = qdict_get_try_str(qdict, "arg3");
 569
 570     if (arg3) {
 571         s = slirp_lookup(mon, arg1, arg2);
 572         redir_str = arg3;
 573     } else if (arg2) {
 574         s = slirp_lookup(mon, NULL, arg1);
 575         redir_str = arg2;
 576     } else {
 577         s = slirp_lookup(mon, NULL, NULL);
 578         redir_str = arg1;
 579     }
 580     if (s) {
 581         Error *err = NULL;
 582         if (slirp_hostfwd(s, redir_str, &err) < 0) {
 583             error_report_err(err);
 584         }
 585     }
 586
 587 }
 588
 589 #ifndef _WIN32
 590
 591 /* automatic user mode samba server configuration */
 592 static void slirp_smb_cleanup(SlirpState *s)
 593 {
 594     int ret;
 595
 596     if (s->smb_dir) {
 597         gchar *cmd = g_strdup_printf("rm -rf %s", s->smb_dir);
 598         ret = system(cmd);
 599         if (ret == -1 || !WIFEXITED(ret)) {
 600             error_report("'%s' failed.", cmd);
 601         } else if (WEXITSTATUS(ret)) {
 602             error_report("'%s' failed. Error code: %d",
 603                          cmd, WEXITSTATUS(ret));
 604         }
 605         g_free(cmd);
 606         g_free(s->smb_dir);
 607         s->smb_dir = NULL;
 608     }
 609 }
 610
 611 static int slirp_smb(SlirpState* s, const char *exported_dir,
 612                      struct in_addr vserver_addr, Error **errp)
 613 {
 614     char *smb_conf;
 615     char *smb_cmdline;
 616     struct passwd *passwd;
 617     FILE *f;
 618
 619     passwd = getpwuid(geteuid());
 620     if (!passwd) {
 621         error_setg(errp, "Failed to retrieve user name");
 622         return -1;
 623     }
 624
 625     if (access(CONFIG_SMBD_COMMAND, F_OK)) {
 626         error_setg(errp, "Could not find '%s', please install it",
 627                    CONFIG_SMBD_COMMAND);
 628         return -1;
 629     }
 630
 631     if (access(exported_dir, R_OK | X_OK)) {
 632         error_setg(errp, "Error accessing shared directory '%s': %s",
 633                    exported_dir, strerror(errno));
 634         return -1;
 635     }
 636
 637     s->smb_dir = g_dir_make_tmp("qemu-smb.XXXXXX", NULL);
 638     if (!s->smb_dir) {
 639         error_setg(errp, "Could not create samba server dir");
 640         return -1;
 641     }
 642     smb_conf = g_strdup_printf("%s/%s", s->smb_dir, "smb.conf");
 643
 644     f = fopen(smb_conf, "w");
 645     if (!f) {
 646         slirp_smb_cleanup(s);
 647         error_setg(errp,
 648                    "Could not create samba server configuration file '%s'",
 649                     smb_conf);
 650         g_free(smb_conf);
 651         return -1;
 652     }
 653     fprintf(f,
 654             "[global]\n"
 655             "private dir=%s\n"
 656             "interfaces=127.0.0.1\n"
 657             "bind interfaces only=yes\n"
 658             "pid directory=%s\n"
 659             "lock directory=%s\n"
 660             "state directory=%s\n"
 661             "cache directory=%s\n"
 662             "ncalrpc dir=%s/ncalrpc\n"
 663             "log file=%s/log.smbd\n"
 664             "smb passwd file=%s/smbpasswd\n"
 665             "security = user\n"
 666             "map to guest = Bad User\n"
 667             "load printers = no\n"
 668             "printing = bsd\n"
 669             "disable spoolss = yes\n"
 670             "usershare max shares = 0\n"
 671             "[qemu]\n"
 672             "path=%s\n"
 673             "read only=no\n"
 674             "guest ok=yes\n"
 675             "force user=%s\n",
 676             s->smb_dir,
 677             s->smb_dir,
 678             s->smb_dir,
 679             s->smb_dir,
 680             s->smb_dir,
 681             s->smb_dir,
 682             s->smb_dir,
 683             s->smb_dir,
 684             exported_dir,
 685             passwd->pw_name
 686             );
 687     fclose(f);
 688
 689     smb_cmdline = g_strdup_printf("%s -l %s -s %s",
 690              CONFIG_SMBD_COMMAND, s->smb_dir, smb_conf);
 691     g_free(smb_conf);
 692
 693     if (slirp_add_exec(s->slirp, 0, smb_cmdline, &vserver_addr, 139) < 0 ||
 694         slirp_add_exec(s->slirp, 0, smb_cmdline, &vserver_addr, 445) < 0) {
 695         slirp_smb_cleanup(s);
 696         g_free(smb_cmdline);
 697         error_setg(errp, "Conflicting/invalid smbserver address");
 698         return -1;
 699     }
 700     g_free(smb_cmdline);
 701     return 0;
 702 }
 703
 704 #endif /* !defined(_WIN32) */
 705
 706 struct GuestFwd {
 707     CharBackend hd;
 708     struct in_addr server;
 709     int port;
 710     Slirp *slirp;
 711 };
 712
 713 static int guestfwd_can_read(void *opaque)
 714 {
 715     struct GuestFwd *fwd = opaque;
 716     return slirp_socket_can_recv(fwd->slirp, fwd->server, fwd->port);
 717 }
 718
 719 static void guestfwd_read(void *opaque, const uint8_t *buf, int size)
 720 {
 721     struct GuestFwd *fwd = opaque;
 722     slirp_socket_recv(fwd->slirp, fwd->server, fwd->port, buf, size);
 723 }
 724
 725 static int slirp_guestfwd(SlirpState *s, const char *config_str, Error **errp)
 726 {
 727     struct in_addr server = { .s_addr = 0 };
 728     struct GuestFwd *fwd;
 729     const char *p;
 730     char buf[128];
 731     char *end;
 732     int port;
 733
 734     p = config_str;
 735     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 736         goto fail_syntax;
 737     }
 738     if (strcmp(buf, "tcp") && buf[0] != '\0') {
 739         goto fail_syntax;
 740     }
 741     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 742         goto fail_syntax;
 743     }
 744     if (buf[0] != '\0' && !inet_aton(buf, &server)) {
 745         goto fail_syntax;
 746     }
 747     if (get_str_sep(buf, sizeof(buf), &p, '-') < 0) {
 748         goto fail_syntax;
 749     }
 750     port = strtol(buf, &end, 10);
 751     if (*end != '\0' || port < 1 || port > 65535) {
 752         goto fail_syntax;
 753     }
 754
 755     snprintf(buf, sizeof(buf), "guestfwd.tcp.%d", port);
 756
 757     if ((strlen(p) > 4) && !strncmp(p, "cmd:", 4)) {
 758         if (slirp_add_exec(s->slirp, 0, &p[4], &server, port) < 0) {
 759             error_setg(errp, "Conflicting/invalid host:port in guest "
 760                        "forwarding rule '%s'", config_str);
 761             return -1;
 762         }
 763     } else {
 764         Error *err = NULL;
 765         Chardev *chr = qemu_chr_new(buf, p);
 766
 767         if (!chr) {
 768             error_setg(errp, "Could not open guest forwarding device '%s'",
 769                        buf);
 770             return -1;
 771         }
 772
 773         fwd = g_new(struct GuestFwd, 1);
 774         qemu_chr_fe_init(&fwd->hd, chr, &err);
 775         if (err) {
 776             error_propagate(errp, err);
 777             g_free(fwd);
 778             return -1;
 779         }
 780
 781         if (slirp_add_exec(s->slirp, 3, &fwd->hd, &server, port) < 0) {
 782             error_setg(errp, "Conflicting/invalid host:port in guest "
 783                        "forwarding rule '%s'", config_str);
 784             g_free(fwd);
 785             return -1;
 786         }
 787         fwd->server = server;
 788         fwd->port = port;
 789         fwd->slirp = s->slirp;
 790
 791         qemu_chr_fe_set_handlers(&fwd->hd, guestfwd_can_read, guestfwd_read,
 792                                  NULL, NULL, fwd, NULL, true);
 793     }
 794     return 0;
 795
 796  fail_syntax:
 797     error_setg(errp, "Invalid guest forwarding rule '%s'", config_str);
 798     return -1;
 799 }
 800
 801 void hmp_info_usernet(Monitor *mon, const QDict *qdict)
 802 {
 803     SlirpState *s;
 804
 805     QTAILQ_FOREACH(s, &slirp_stacks, entry) {
 806         int id;
 807         bool got_hub_id = net_hub_id_for_client(&s->nc, &id) == 0;
 808         monitor_printf(mon, "Hub %d (%s):\n",
 809                        got_hub_id ? id : -1,
 810                        s->nc.name);
 811         slirp_connection_info(s->slirp, mon);
 812     }
 813 }
 814
 815 static void
 816 net_init_slirp_configs(const StringList *fwd, int flags)
 817 {
 818     while (fwd) {
 819         struct slirp_config_str *config;
 820
 821         config = g_malloc0(sizeof(*config));
 822         pstrcpy(config->str, sizeof(config->str), fwd->value->str);
 823         config->flags = flags;
 824         config->next = slirp_configs;
 825         slirp_configs = config;
 826
 827         fwd = fwd->next;
 828     }
 829 }
 830
 831 static const char **slirp_dnssearch(const StringList *dnsname)
 832 {
 833     const StringList *c = dnsname;
 834     size_t i = 0, num_opts = 0;
 835     const char **ret;
 836
 837     while (c) {
 838         num_opts++;
 839         c = c->next;
 840     }
 841
 842     if (num_opts == 0) {
 843         return NULL;
 844     }
 845
 846     ret = g_malloc((num_opts + 1) * sizeof(*ret));
 847     c = dnsname;
 848     while (c) {
 849         ret[i++] = c->value->str;
 850         c = c->next;
 851     }
 852     ret[i] = NULL;
 853     return ret;
 854 }
 855
 856 int net_init_slirp(const Netdev *netdev, const char *name,
 857                    NetClientState *peer, Error **errp)
 858 {
 859     struct slirp_config_str *config;
 860     char *vnet;
 861     int ret;
 862     const NetdevUserOptions *user;
 863     const char **dnssearch;
 864     bool ipv4 = true, ipv6 = true;
 865
 866     assert(netdev->type == NET_CLIENT_DRIVER_USER);
 867     user = &netdev->u.user;
 868
 869     if ((user->has_ipv6 && user->ipv6 && !user->has_ipv4) ||
 870         (user->has_ipv4 && !user->ipv4)) {
 871         ipv4 = 0;
 872     }
 873     if ((user->has_ipv4 && user->ipv4 && !user->has_ipv6) ||
 874         (user->has_ipv6 && !user->ipv6)) {
 875         ipv6 = 0;
 876     }
 877
 878     vnet = user->has_net ? g_strdup(user->net) :
 879            user->has_ip  ? g_strdup_printf("%s/24", user->ip) :
 880            NULL;
 881
 882     dnssearch = slirp_dnssearch(user->dnssearch);
 883
 884     /* all optional fields are initialized to "all bits zero" */
 885
 886     net_init_slirp_configs(user->hostfwd, SLIRP_CFG_HOSTFWD);
 887     net_init_slirp_configs(user->guestfwd, 0);
 888
 889     ret = net_slirp_init(peer, "user", name, user->q_restrict,
 890                          ipv4, vnet, user->host,
 891                          ipv6, user->ipv6_prefix, user->ipv6_prefixlen,
 892                          user->ipv6_host, user->hostname, user->tftp,
 893                          user->bootfile, user->dhcpstart,
 894                          user->dns, user->ipv6_dns, user->smb,
 895                          user->smbserver, dnssearch, user->domainname, errp);
 896
 897     while (slirp_configs) {
 898         config = slirp_configs;
 899         slirp_configs = config->next;
 900         g_free(config);
 901     }
 902
 903     g_free(vnet);
 904     g_free(dnssearch);
 905
 906     return ret;
 907 }