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 "qemu/log.h"
  27 #include "net/slirp.h"
  28
  29
  30 #if defined(CONFIG_SMBD_COMMAND)
  31 #include <pwd.h>
  32 #include <sys/wait.h>
  33 #endif
  34 #include "net/eth.h"
  35 #include "net/net.h"
  36 #include "clients.h"
  37 #include "hub.h"
  38 #include "monitor/monitor.h"
  39 #include "qemu/error-report.h"
  40 #include "qemu/sockets.h"
  41 #include <libslirp.h>
  42 #include "chardev/char-fe.h"
  43 #include "sysemu/sysemu.h"
  44 #include "qemu/cutils.h"
  45 #include "qapi/error.h"
  46 #include "qapi/qmp/qdict.h"
  47 #include "util.h"
  48 #include "migration/register.h"
  49 #include "migration/vmstate.h"
  50 #include "migration/qemu-file-types.h"
  51
  52 static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
  53 {
  54     const char *p, *p1;
  55     int len;
  56     p = *pp;
  57     p1 = strchr(p, sep);
  58     if (!p1)
  59         return -1;
  60     len = p1 - p;
  61     p1++;
  62     if (buf_size > 0) {
  63         if (len > buf_size - 1)
  64             len = buf_size - 1;
  65         memcpy(buf, p, len);
  66         buf[len] = '\0';
  67     }
  68     *pp = p1;
  69     return 0;
  70 }
  71
  72 /* slirp network adapter */
  73
  74 #define SLIRP_CFG_HOSTFWD 1
  75
  76 struct slirp_config_str {
  77     struct slirp_config_str *next;
  78     int flags;
  79     char str[1024];
  80 };
  81
  82 struct GuestFwd {
  83     CharBackend hd;
  84     struct in_addr server;
  85     int port;
  86     Slirp *slirp;
  87 };
  88
  89 typedef struct SlirpState {
  90     NetClientState nc;
  91     QTAILQ_ENTRY(SlirpState) entry;
  92     Slirp *slirp;
  93     Notifier poll_notifier;
  94     Notifier exit_notifier;
  95 #if defined(CONFIG_SMBD_COMMAND)
  96     gchar *smb_dir;
  97 #endif
  98     GSList *fwd;
  99 } SlirpState;
 100
 101 static struct slirp_config_str *slirp_configs;
 102 static QTAILQ_HEAD(, SlirpState) slirp_stacks =
 103     QTAILQ_HEAD_INITIALIZER(slirp_stacks);
 104
 105 static int slirp_hostfwd(SlirpState *s, const char *redir_str, Error **errp);
 106 static int slirp_guestfwd(SlirpState *s, const char *config_str, Error **errp);
 107
 108 #if defined(CONFIG_SMBD_COMMAND)
 109 static int slirp_smb(SlirpState *s, const char *exported_dir,
 110                      struct in_addr vserver_addr, Error **errp);
 111 static void slirp_smb_cleanup(SlirpState *s);
 112 #else
 113 static inline void slirp_smb_cleanup(SlirpState *s) { }
 114 #endif
 115
 116 static ssize_t net_slirp_send_packet(const void *pkt, size_t pkt_len,
 117                                      void *opaque)
 118 {
 119     SlirpState *s = opaque;
 120     uint8_t min_pkt[ETH_ZLEN];
 121     size_t min_pktsz = sizeof(min_pkt);
 122
 123     if (net_peer_needs_padding(&s->nc)) {
 124         if (eth_pad_short_frame(min_pkt, &min_pktsz, pkt, pkt_len)) {
 125             pkt = min_pkt;
 126             pkt_len = min_pktsz;
 127         }
 128     }
 129
 130     return qemu_send_packet(&s->nc, pkt, pkt_len);
 131 }
 132
 133 static ssize_t net_slirp_receive(NetClientState *nc, const uint8_t *buf, size_t size)
 134 {
 135     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
 136
 137     slirp_input(s->slirp, buf, size);
 138
 139     return size;
 140 }
 141
 142 static void slirp_smb_exit(Notifier *n, void *data)
 143 {
 144     SlirpState *s = container_of(n, SlirpState, exit_notifier);
 145     slirp_smb_cleanup(s);
 146 }
 147
 148 static void slirp_free_fwd(gpointer data)
 149 {
 150     struct GuestFwd *fwd = data;
 151
 152     qemu_chr_fe_deinit(&fwd->hd, true);
 153     g_free(data);
 154 }
 155
 156 static void net_slirp_cleanup(NetClientState *nc)
 157 {
 158     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
 159
 160     g_slist_free_full(s->fwd, slirp_free_fwd);
 161     main_loop_poll_remove_notifier(&s->poll_notifier);
 162     unregister_savevm(NULL, "slirp", s->slirp);
 163     slirp_cleanup(s->slirp);
 164     if (s->exit_notifier.notify) {
 165         qemu_remove_exit_notifier(&s->exit_notifier);
 166     }
 167     slirp_smb_cleanup(s);
 168     QTAILQ_REMOVE(&slirp_stacks, s, entry);
 169 }
 170
 171 static NetClientInfo net_slirp_info = {
 172     .type = NET_CLIENT_DRIVER_USER,
 173     .size = sizeof(SlirpState),
 174     .receive = net_slirp_receive,
 175     .cleanup = net_slirp_cleanup,
 176 };
 177
 178 static void net_slirp_guest_error(const char *msg, void *opaque)
 179 {
 180     qemu_log_mask(LOG_GUEST_ERROR, "%s", msg);
 181 }
 182
 183 static int64_t net_slirp_clock_get_ns(void *opaque)
 184 {
 185     return qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
 186 }
 187
 188 typedef struct SlirpTimer SlirpTimer;
 189 struct SlirpTimer {
 190     QEMUTimer timer;
 191 #if SLIRP_CHECK_VERSION(4,7,0)
 192     Slirp *slirp;
 193     SlirpTimerId id;
 194     void *cb_opaque;
 195 #endif
 196 };
 197
 198 #if SLIRP_CHECK_VERSION(4,7,0)
 199 static void net_slirp_init_completed(Slirp *slirp, void *opaque)
 200 {
 201     SlirpState *s = opaque;
 202     s->slirp = slirp;
 203 }
 204
 205 static void net_slirp_timer_cb(void *opaque)
 206 {
 207     SlirpTimer *t = opaque;
 208     slirp_handle_timer(t->slirp, t->id, t->cb_opaque);
 209 }
 210
 211 static void *net_slirp_timer_new_opaque(SlirpTimerId id,
 212                                         void *cb_opaque, void *opaque)
 213 {
 214     SlirpState *s = opaque;
 215     SlirpTimer *t = g_new(SlirpTimer, 1);
 216     t->slirp = s->slirp;
 217     t->id = id;
 218     t->cb_opaque = cb_opaque;
 219     timer_init_full(&t->timer, NULL, QEMU_CLOCK_VIRTUAL,
 220                     SCALE_MS, QEMU_TIMER_ATTR_EXTERNAL,
 221                     net_slirp_timer_cb, t);
 222     return t;
 223 }
 224 #else
 225 static void *net_slirp_timer_new(SlirpTimerCb cb,
 226                                  void *cb_opaque, void *opaque)
 227 {
 228     SlirpTimer *t = g_new(SlirpTimer, 1);
 229     timer_init_full(&t->timer, NULL, QEMU_CLOCK_VIRTUAL,
 230                     SCALE_MS, QEMU_TIMER_ATTR_EXTERNAL,
 231                     cb, cb_opaque);
 232     return t;
 233 }
 234 #endif
 235
 236 static void net_slirp_timer_free(void *timer, void *opaque)
 237 {
 238     SlirpTimer *t = timer;
 239     timer_del(&t->timer);
 240     g_free(t);
 241 }
 242
 243 static void net_slirp_timer_mod(void *timer, int64_t expire_timer,
 244                                 void *opaque)
 245 {
 246     SlirpTimer *t = timer;
 247     timer_mod(&t->timer, expire_timer);
 248 }
 249
 250 static void net_slirp_register_poll_fd(int fd, void *opaque)
 251 {
 252 #ifdef WIN32
 253     AioContext *ctxt = qemu_get_aio_context();
 254
 255     if (WSAEventSelect(fd, event_notifier_get_handle(&ctxt->notifier),
 256                        FD_READ | FD_ACCEPT | FD_CLOSE |
 257                        FD_CONNECT | FD_WRITE | FD_OOB) != 0) {
 258         error_setg_win32(&error_warn, WSAGetLastError(), "failed to WSAEventSelect()");
 259     }
 260 #endif
 261 }
 262
 263 static void net_slirp_unregister_poll_fd(int fd, void *opaque)
 264 {
 265 #ifdef WIN32
 266     if (WSAEventSelect(fd, NULL, 0) != 0) {
 267         error_setg_win32(&error_warn, WSAGetLastError(), "failed to WSAEventSelect()");
 268     }
 269 #endif
 270 }
 271
 272 static void net_slirp_notify(void *opaque)
 273 {
 274     qemu_notify_event();
 275 }
 276
 277 static const SlirpCb slirp_cb = {
 278     .send_packet = net_slirp_send_packet,
 279     .guest_error = net_slirp_guest_error,
 280     .clock_get_ns = net_slirp_clock_get_ns,
 281 #if SLIRP_CHECK_VERSION(4,7,0)
 282     .init_completed = net_slirp_init_completed,
 283     .timer_new_opaque = net_slirp_timer_new_opaque,
 284 #else
 285     .timer_new = net_slirp_timer_new,
 286 #endif
 287     .timer_free = net_slirp_timer_free,
 288     .timer_mod = net_slirp_timer_mod,
 289     .register_poll_fd = net_slirp_register_poll_fd,
 290     .unregister_poll_fd = net_slirp_unregister_poll_fd,
 291     .notify = net_slirp_notify,
 292 };
 293
 294 static int slirp_poll_to_gio(int events)
 295 {
 296     int ret = 0;
 297
 298     if (events & SLIRP_POLL_IN) {
 299         ret |= G_IO_IN;
 300     }
 301     if (events & SLIRP_POLL_OUT) {
 302         ret |= G_IO_OUT;
 303     }
 304     if (events & SLIRP_POLL_PRI) {
 305         ret |= G_IO_PRI;
 306     }
 307     if (events & SLIRP_POLL_ERR) {
 308         ret |= G_IO_ERR;
 309     }
 310     if (events & SLIRP_POLL_HUP) {
 311         ret |= G_IO_HUP;
 312     }
 313
 314     return ret;
 315 }
 316
 317 static int net_slirp_add_poll(int fd, int events, void *opaque)
 318 {
 319     GArray *pollfds = opaque;
 320     GPollFD pfd = {
 321         .fd = fd,
 322         .events = slirp_poll_to_gio(events),
 323     };
 324     int idx = pollfds->len;
 325     g_array_append_val(pollfds, pfd);
 326     return idx;
 327 }
 328
 329 static int slirp_gio_to_poll(int events)
 330 {
 331     int ret = 0;
 332
 333     if (events & G_IO_IN) {
 334         ret |= SLIRP_POLL_IN;
 335     }
 336     if (events & G_IO_OUT) {
 337         ret |= SLIRP_POLL_OUT;
 338     }
 339     if (events & G_IO_PRI) {
 340         ret |= SLIRP_POLL_PRI;
 341     }
 342     if (events & G_IO_ERR) {
 343         ret |= SLIRP_POLL_ERR;
 344     }
 345     if (events & G_IO_HUP) {
 346         ret |= SLIRP_POLL_HUP;
 347     }
 348
 349     return ret;
 350 }
 351
 352 static int net_slirp_get_revents(int idx, void *opaque)
 353 {
 354     GArray *pollfds = opaque;
 355
 356     return slirp_gio_to_poll(g_array_index(pollfds, GPollFD, idx).revents);
 357 }
 358
 359 static void net_slirp_poll_notify(Notifier *notifier, void *data)
 360 {
 361     MainLoopPoll *poll = data;
 362     SlirpState *s = container_of(notifier, SlirpState, poll_notifier);
 363
 364     switch (poll->state) {
 365     case MAIN_LOOP_POLL_FILL:
 366         slirp_pollfds_fill(s->slirp, &poll->timeout,
 367                            net_slirp_add_poll, poll->pollfds);
 368         break;
 369     case MAIN_LOOP_POLL_OK:
 370     case MAIN_LOOP_POLL_ERR:
 371         slirp_pollfds_poll(s->slirp, poll->state == MAIN_LOOP_POLL_ERR,
 372                            net_slirp_get_revents, poll->pollfds);
 373         break;
 374     default:
 375         g_assert_not_reached();
 376     }
 377 }
 378
 379 static ssize_t
 380 net_slirp_stream_read(void *buf, size_t size, void *opaque)
 381 {
 382     QEMUFile *f = opaque;
 383
 384     return qemu_get_buffer(f, buf, size);
 385 }
 386
 387 static ssize_t
 388 net_slirp_stream_write(const void *buf, size_t size, void *opaque)
 389 {
 390     QEMUFile *f = opaque;
 391
 392     qemu_put_buffer(f, buf, size);
 393     if (qemu_file_get_error(f)) {
 394         return -1;
 395     }
 396
 397     return size;
 398 }
 399
 400 static int net_slirp_state_load(QEMUFile *f, void *opaque, int version_id)
 401 {
 402     Slirp *slirp = opaque;
 403
 404     return slirp_state_load(slirp, version_id, net_slirp_stream_read, f);
 405 }
 406
 407 static void net_slirp_state_save(QEMUFile *f, void *opaque)
 408 {
 409     Slirp *slirp = opaque;
 410
 411     slirp_state_save(slirp, net_slirp_stream_write, f);
 412 }
 413
 414 static SaveVMHandlers savevm_slirp_state = {
 415     .save_state = net_slirp_state_save,
 416     .load_state = net_slirp_state_load,
 417 };
 418
 419 static int net_slirp_init(NetClientState *peer, const char *model,
 420                           const char *name, int restricted,
 421                           bool ipv4, const char *vnetwork, const char *vhost,
 422                           bool ipv6, const char *vprefix6, int vprefix6_len,
 423                           const char *vhost6,
 424                           const char *vhostname, const char *tftp_export,
 425                           const char *bootfile, const char *vdhcp_start,
 426                           const char *vnameserver, const char *vnameserver6,
 427                           const char *smb_export, const char *vsmbserver,
 428                           const char **dnssearch, const char *vdomainname,
 429                           const char *tftp_server_name,
 430                           Error **errp)
 431 {
 432     /* default settings according to historic slirp */
 433     struct in_addr net  = { .s_addr = htonl(0x0a000200) }; /* 10.0.2.0 */
 434     struct in_addr mask = { .s_addr = htonl(0xffffff00) }; /* 255.255.255.0 */
 435     struct in_addr host = { .s_addr = htonl(0x0a000202) }; /* 10.0.2.2 */
 436     struct in_addr dhcp = { .s_addr = htonl(0x0a00020f) }; /* 10.0.2.15 */
 437     struct in_addr dns  = { .s_addr = htonl(0x0a000203) }; /* 10.0.2.3 */
 438     struct in6_addr ip6_prefix;
 439     struct in6_addr ip6_host;
 440     struct in6_addr ip6_dns;
 441 #if defined(CONFIG_SMBD_COMMAND)
 442     struct in_addr smbsrv = { .s_addr = 0 };
 443 #endif
 444     SlirpConfig cfg = { 0 };
 445     NetClientState *nc;
 446     SlirpState *s;
 447     char buf[20];
 448     uint32_t addr;
 449     int shift;
 450     char *end;
 451     struct slirp_config_str *config;
 452
 453     if (!ipv4 && (vnetwork || vhost || vnameserver)) {
 454         error_setg(errp, "IPv4 disabled but netmask/host/dns provided");
 455         return -1;
 456     }
 457
 458     if (!ipv6 && (vprefix6 || vhost6 || vnameserver6)) {
 459         error_setg(errp, "IPv6 disabled but prefix/host6/dns6 provided");
 460         return -1;
 461     }
 462
 463     if (!ipv4 && !ipv6) {
 464         /* It doesn't make sense to disable both */
 465         error_setg(errp, "IPv4 and IPv6 disabled");
 466         return -1;
 467     }
 468
 469     if (vnetwork) {
 470         if (get_str_sep(buf, sizeof(buf), &vnetwork, '/') < 0) {
 471             if (!inet_aton(vnetwork, &net)) {
 472                 error_setg(errp, "Failed to parse netmask");
 473                 return -1;
 474             }
 475             addr = ntohl(net.s_addr);
 476             if (!(addr & 0x80000000)) {
 477                 mask.s_addr = htonl(0xff000000); /* class A */
 478             } else if ((addr & 0xfff00000) == 0xac100000) {
 479                 mask.s_addr = htonl(0xfff00000); /* priv. 172.16.0.0/12 */
 480             } else if ((addr & 0xc0000000) == 0x80000000) {
 481                 mask.s_addr = htonl(0xffff0000); /* class B */
 482             } else if ((addr & 0xffff0000) == 0xc0a80000) {
 483                 mask.s_addr = htonl(0xffff0000); /* priv. 192.168.0.0/16 */
 484             } else if ((addr & 0xffff0000) == 0xc6120000) {
 485                 mask.s_addr = htonl(0xfffe0000); /* tests 198.18.0.0/15 */
 486             } else if ((addr & 0xe0000000) == 0xe0000000) {
 487                 mask.s_addr = htonl(0xffffff00); /* class C */
 488             } else {
 489                 mask.s_addr = htonl(0xfffffff0); /* multicast/reserved */
 490             }
 491         } else {
 492             if (!inet_aton(buf, &net)) {
 493                 error_setg(errp, "Failed to parse netmask");
 494                 return -1;
 495             }
 496             shift = strtol(vnetwork, &end, 10);
 497             if (*end != '\0') {
 498                 if (!inet_aton(vnetwork, &mask)) {
 499                     error_setg(errp,
 500                                "Failed to parse netmask (trailing chars)");
 501                     return -1;
 502                 }
 503             } else if (shift < 4 || shift > 32) {
 504                 error_setg(errp,
 505                            "Invalid netmask provided (must be in range 4-32)");
 506                 return -1;
 507             } else {
 508                 mask.s_addr = htonl(0xffffffff << (32 - shift));
 509             }
 510         }
 511         net.s_addr &= mask.s_addr;
 512         host.s_addr = net.s_addr | (htonl(0x0202) & ~mask.s_addr);
 513         dhcp.s_addr = net.s_addr | (htonl(0x020f) & ~mask.s_addr);
 514         dns.s_addr  = net.s_addr | (htonl(0x0203) & ~mask.s_addr);
 515     }
 516
 517     if (vhost && !inet_aton(vhost, &host)) {
 518         error_setg(errp, "Failed to parse host");
 519         return -1;
 520     }
 521     if ((host.s_addr & mask.s_addr) != net.s_addr) {
 522         error_setg(errp, "Host doesn't belong to network");
 523         return -1;
 524     }
 525
 526     if (vnameserver && !inet_aton(vnameserver, &dns)) {
 527         error_setg(errp, "Failed to parse DNS");
 528         return -1;
 529     }
 530     if (restricted && (dns.s_addr & mask.s_addr) != net.s_addr) {
 531         error_setg(errp, "DNS doesn't belong to network");
 532         return -1;
 533     }
 534     if (dns.s_addr == host.s_addr) {
 535         error_setg(errp, "DNS must be different from host");
 536         return -1;
 537     }
 538
 539     if (vdhcp_start && !inet_aton(vdhcp_start, &dhcp)) {
 540         error_setg(errp, "Failed to parse DHCP start address");
 541         return -1;
 542     }
 543     if ((dhcp.s_addr & mask.s_addr) != net.s_addr) {
 544         error_setg(errp, "DHCP doesn't belong to network");
 545         return -1;
 546     }
 547     if (dhcp.s_addr == host.s_addr || dhcp.s_addr == dns.s_addr) {
 548         error_setg(errp, "DHCP must be different from host and DNS");
 549         return -1;
 550     }
 551
 552 #if defined(CONFIG_SMBD_COMMAND)
 553     if (vsmbserver && !inet_aton(vsmbserver, &smbsrv)) {
 554         error_setg(errp, "Failed to parse SMB address");
 555         return -1;
 556     }
 557 #endif
 558
 559     if (!vprefix6) {
 560         vprefix6 = "fec0::";
 561     }
 562     if (!inet_pton(AF_INET6, vprefix6, &ip6_prefix)) {
 563         error_setg(errp, "Failed to parse IPv6 prefix");
 564         return -1;
 565     }
 566
 567     if (!vprefix6_len) {
 568         vprefix6_len = 64;
 569     }
 570     if (vprefix6_len < 0 || vprefix6_len > 126) {
 571         error_setg(errp,
 572                    "Invalid IPv6 prefix provided "
 573                    "(IPv6 prefix length must be between 0 and 126)");
 574         return -1;
 575     }
 576
 577     if (vhost6) {
 578         if (!inet_pton(AF_INET6, vhost6, &ip6_host)) {
 579             error_setg(errp, "Failed to parse IPv6 host");
 580             return -1;
 581         }
 582         if (!in6_equal_net(&ip6_prefix, &ip6_host, vprefix6_len)) {
 583             error_setg(errp, "IPv6 Host doesn't belong to network");
 584             return -1;
 585         }
 586     } else {
 587         ip6_host = ip6_prefix;
 588         ip6_host.s6_addr[15] |= 2;
 589     }
 590
 591     if (vnameserver6) {
 592         if (!inet_pton(AF_INET6, vnameserver6, &ip6_dns)) {
 593             error_setg(errp, "Failed to parse IPv6 DNS");
 594             return -1;
 595         }
 596         if (restricted && !in6_equal_net(&ip6_prefix, &ip6_dns, vprefix6_len)) {
 597             error_setg(errp, "IPv6 DNS doesn't belong to network");
 598             return -1;
 599         }
 600     } else {
 601         ip6_dns = ip6_prefix;
 602         ip6_dns.s6_addr[15] |= 3;
 603     }
 604
 605     if (vdomainname && !*vdomainname) {
 606         error_setg(errp, "'domainname' parameter cannot be empty");
 607         return -1;
 608     }
 609
 610     if (vdomainname && strlen(vdomainname) > 255) {
 611         error_setg(errp, "'domainname' parameter cannot exceed 255 bytes");
 612         return -1;
 613     }
 614
 615     if (vhostname && strlen(vhostname) > 255) {
 616         error_setg(errp, "'vhostname' parameter cannot exceed 255 bytes");
 617         return -1;
 618     }
 619
 620     if (tftp_server_name && strlen(tftp_server_name) > 255) {
 621         error_setg(errp, "'tftp-server-name' parameter cannot exceed 255 bytes");
 622         return -1;
 623     }
 624
 625     nc = qemu_new_net_client(&net_slirp_info, peer, model, name);
 626
 627     qemu_set_info_str(nc, "net=%s,restrict=%s", inet_ntoa(net),
 628                       restricted ? "on" : "off");
 629
 630     s = DO_UPCAST(SlirpState, nc, nc);
 631
 632     cfg.version = SLIRP_CHECK_VERSION(4,7,0) ? 4 : 1;
 633     cfg.restricted = restricted;
 634     cfg.in_enabled = ipv4;
 635     cfg.vnetwork = net;
 636     cfg.vnetmask = mask;
 637     cfg.vhost = host;
 638     cfg.in6_enabled = ipv6;
 639     cfg.vprefix_addr6 = ip6_prefix;
 640     cfg.vprefix_len = vprefix6_len;
 641     cfg.vhost6 = ip6_host;
 642     cfg.vhostname = vhostname;
 643     cfg.tftp_server_name = tftp_server_name;
 644     cfg.tftp_path = tftp_export;
 645     cfg.bootfile = bootfile;
 646     cfg.vdhcp_start = dhcp;
 647     cfg.vnameserver = dns;
 648     cfg.vnameserver6 = ip6_dns;
 649     cfg.vdnssearch = dnssearch;
 650     cfg.vdomainname = vdomainname;
 651     s->slirp = slirp_new(&cfg, &slirp_cb, s);
 652     QTAILQ_INSERT_TAIL(&slirp_stacks, s, entry);
 653
 654     /*
 655      * Make sure the current bitstream version of slirp is 4, to avoid
 656      * QEMU migration incompatibilities, if upstream slirp bumped the
 657      * version.
 658      *
 659      * FIXME: use bitfields of features? teach libslirp to save with
 660      * specific version?
 661      */
 662     g_assert(slirp_state_version() == 4);
 663     register_savevm_live("slirp", VMSTATE_INSTANCE_ID_ANY,
 664                          slirp_state_version(), &savevm_slirp_state, s->slirp);
 665
 666     s->poll_notifier.notify = net_slirp_poll_notify;
 667     main_loop_poll_add_notifier(&s->poll_notifier);
 668
 669     for (config = slirp_configs; config; config = config->next) {
 670         if (config->flags & SLIRP_CFG_HOSTFWD) {
 671             if (slirp_hostfwd(s, config->str, errp) < 0) {
 672                 goto error;
 673             }
 674         } else {
 675             if (slirp_guestfwd(s, config->str, errp) < 0) {
 676                 goto error;
 677             }
 678         }
 679     }
 680 #if defined(CONFIG_SMBD_COMMAND)
 681     if (smb_export) {
 682         if (slirp_smb(s, smb_export, smbsrv, errp) < 0) {
 683             goto error;
 684         }
 685     }
 686 #endif
 687
 688     s->exit_notifier.notify = slirp_smb_exit;
 689     qemu_add_exit_notifier(&s->exit_notifier);
 690     return 0;
 691
 692 error:
 693     qemu_del_net_client(nc);
 694     return -1;
 695 }
 696
 697 static SlirpState *slirp_lookup(Monitor *mon, const char *id)
 698 {
 699     if (id) {
 700         NetClientState *nc = qemu_find_netdev(id);
 701         if (!nc) {
 702             monitor_printf(mon, "unrecognized netdev id '%s'\n", id);
 703             return NULL;
 704         }
 705         if (strcmp(nc->model, "user")) {
 706             monitor_printf(mon, "invalid device specified\n");
 707             return NULL;
 708         }
 709         return DO_UPCAST(SlirpState, nc, nc);
 710     } else {
 711         if (QTAILQ_EMPTY(&slirp_stacks)) {
 712             monitor_printf(mon, "user mode network stack not in use\n");
 713             return NULL;
 714         }
 715         return QTAILQ_FIRST(&slirp_stacks);
 716     }
 717 }
 718
 719 void hmp_hostfwd_remove(Monitor *mon, const QDict *qdict)
 720 {
 721     struct sockaddr_in host_addr = {
 722         .sin_family = AF_INET,
 723         .sin_addr = {
 724             .s_addr = INADDR_ANY,
 725         },
 726     };
 727     int host_port;
 728     char buf[256];
 729     const char *src_str, *p;
 730     SlirpState *s;
 731     int is_udp = 0;
 732     int err;
 733     const char *arg1 = qdict_get_str(qdict, "arg1");
 734     const char *arg2 = qdict_get_try_str(qdict, "arg2");
 735
 736     if (arg2) {
 737         s = slirp_lookup(mon, arg1);
 738         src_str = arg2;
 739     } else {
 740         s = slirp_lookup(mon, NULL);
 741         src_str = arg1;
 742     }
 743     if (!s) {
 744         return;
 745     }
 746
 747     p = src_str;
 748     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 749         goto fail_syntax;
 750     }
 751
 752     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
 753         is_udp = 0;
 754     } else if (!strcmp(buf, "udp")) {
 755         is_udp = 1;
 756     } else {
 757         goto fail_syntax;
 758     }
 759
 760     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 761         goto fail_syntax;
 762     }
 763     if (buf[0] != '\0' && !inet_aton(buf, &host_addr.sin_addr)) {
 764         goto fail_syntax;
 765     }
 766
 767     if (qemu_strtoi(p, NULL, 10, &host_port)) {
 768         goto fail_syntax;
 769     }
 770     host_addr.sin_port = htons(host_port);
 771
 772 #if SLIRP_CHECK_VERSION(4, 5, 0)
 773     err = slirp_remove_hostxfwd(s->slirp, (struct sockaddr *) &host_addr,
 774             sizeof(host_addr), is_udp ? SLIRP_HOSTFWD_UDP : 0);
 775 #else
 776     err = slirp_remove_hostfwd(s->slirp, is_udp, host_addr.sin_addr, host_port);
 777 #endif
 778
 779     monitor_printf(mon, "host forwarding rule for %s %s\n", src_str,
 780                    err ? "not found" : "removed");
 781     return;
 782
 783  fail_syntax:
 784     monitor_printf(mon, "invalid format\n");
 785 }
 786
 787 static int slirp_hostfwd(SlirpState *s, const char *redir_str, Error **errp)
 788 {
 789     struct sockaddr_in host_addr = {
 790         .sin_family = AF_INET,
 791         .sin_addr = {
 792             .s_addr = INADDR_ANY,
 793         },
 794     };
 795     struct sockaddr_in guest_addr = {
 796         .sin_family = AF_INET,
 797         .sin_addr = {
 798             .s_addr = 0,
 799         },
 800     };
 801     int err;
 802     int host_port, guest_port;
 803     const char *p;
 804     char buf[256];
 805     int is_udp;
 806     const char *end;
 807     const char *fail_reason = "Unknown reason";
 808
 809     p = redir_str;
 810     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 811         fail_reason = "No : separators";
 812         goto fail_syntax;
 813     }
 814     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
 815         is_udp = 0;
 816     } else if (!strcmp(buf, "udp")) {
 817         is_udp = 1;
 818     } else {
 819         fail_reason = "Bad protocol name";
 820         goto fail_syntax;
 821     }
 822
 823     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 824         fail_reason = "Missing : separator";
 825         goto fail_syntax;
 826     }
 827     if (buf[0] != '\0' && !inet_aton(buf, &host_addr.sin_addr)) {
 828         fail_reason = "Bad host address";
 829         goto fail_syntax;
 830     }
 831
 832     if (get_str_sep(buf, sizeof(buf), &p, '-') < 0) {
 833         fail_reason = "Bad host port separator";
 834         goto fail_syntax;
 835     }
 836     err = qemu_strtoi(buf, &end, 0, &host_port);
 837     if (err || host_port < 0 || host_port > 65535) {
 838         fail_reason = "Bad host port";
 839         goto fail_syntax;
 840     }
 841     host_addr.sin_port = htons(host_port);
 842
 843     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 844         fail_reason = "Missing guest address";
 845         goto fail_syntax;
 846     }
 847     if (buf[0] != '\0' && !inet_aton(buf, &guest_addr.sin_addr)) {
 848         fail_reason = "Bad guest address";
 849         goto fail_syntax;
 850     }
 851
 852     err = qemu_strtoi(p, &end, 0, &guest_port);
 853     if (err || guest_port < 1 || guest_port > 65535) {
 854         fail_reason = "Bad guest port";
 855         goto fail_syntax;
 856     }
 857     guest_addr.sin_port = htons(guest_port);
 858
 859 #if SLIRP_CHECK_VERSION(4, 5, 0)
 860     err = slirp_add_hostxfwd(s->slirp,
 861             (struct sockaddr *) &host_addr, sizeof(host_addr),
 862             (struct sockaddr *) &guest_addr, sizeof(guest_addr),
 863             is_udp ? SLIRP_HOSTFWD_UDP : 0);
 864 #else
 865     err = slirp_add_hostfwd(s->slirp, is_udp,
 866             host_addr.sin_addr, host_port,
 867             guest_addr.sin_addr, guest_port);
 868 #endif
 869
 870     if (err < 0) {
 871         error_setg(errp, "Could not set up host forwarding rule '%s'",
 872                    redir_str);
 873         return -1;
 874     }
 875     return 0;
 876
 877  fail_syntax:
 878     error_setg(errp, "Invalid host forwarding rule '%s' (%s)", redir_str,
 879                fail_reason);
 880     return -1;
 881 }
 882
 883 void hmp_hostfwd_add(Monitor *mon, const QDict *qdict)
 884 {
 885     const char *redir_str;
 886     SlirpState *s;
 887     const char *arg1 = qdict_get_str(qdict, "arg1");
 888     const char *arg2 = qdict_get_try_str(qdict, "arg2");
 889
 890     if (arg2) {
 891         s = slirp_lookup(mon, arg1);
 892         redir_str = arg2;
 893     } else {
 894         s = slirp_lookup(mon, NULL);
 895         redir_str = arg1;
 896     }
 897     if (s) {
 898         Error *err = NULL;
 899         if (slirp_hostfwd(s, redir_str, &err) < 0) {
 900             error_report_err(err);
 901         }
 902     }
 903
 904 }
 905
 906 #if defined(CONFIG_SMBD_COMMAND)
 907
 908 /* automatic user mode samba server configuration */
 909 static void slirp_smb_cleanup(SlirpState *s)
 910 {
 911     int ret;
 912
 913     if (s->smb_dir) {
 914         gchar *cmd = g_strdup_printf("rm -rf %s", s->smb_dir);
 915         ret = system(cmd);
 916         if (ret == -1 || !WIFEXITED(ret)) {
 917             error_report("'%s' failed.", cmd);
 918         } else if (WEXITSTATUS(ret)) {
 919             error_report("'%s' failed. Error code: %d",
 920                          cmd, WEXITSTATUS(ret));
 921         }
 922         g_free(cmd);
 923         g_free(s->smb_dir);
 924         s->smb_dir = NULL;
 925     }
 926 }
 927
 928 static int slirp_smb(SlirpState* s, const char *exported_dir,
 929                      struct in_addr vserver_addr, Error **errp)
 930 {
 931     char *smb_conf;
 932     char *smb_cmdline;
 933     struct passwd *passwd;
 934     FILE *f;
 935
 936     passwd = getpwuid(geteuid());
 937     if (!passwd) {
 938         error_setg(errp, "Failed to retrieve user name");
 939         return -1;
 940     }
 941
 942     if (access(CONFIG_SMBD_COMMAND, F_OK)) {
 943         error_setg(errp, "Could not find '%s', please install it",
 944                    CONFIG_SMBD_COMMAND);
 945         return -1;
 946     }
 947
 948     if (access(exported_dir, R_OK | X_OK)) {
 949         error_setg(errp, "Error accessing shared directory '%s': %s",
 950                    exported_dir, strerror(errno));
 951         return -1;
 952     }
 953
 954     s->smb_dir = g_dir_make_tmp("qemu-smb.XXXXXX", NULL);
 955     if (!s->smb_dir) {
 956         error_setg(errp, "Could not create samba server dir");
 957         return -1;
 958     }
 959     smb_conf = g_strdup_printf("%s/%s", s->smb_dir, "smb.conf");
 960
 961     f = fopen(smb_conf, "w");
 962     if (!f) {
 963         slirp_smb_cleanup(s);
 964         error_setg(errp,
 965                    "Could not create samba server configuration file '%s'",
 966                     smb_conf);
 967         g_free(smb_conf);
 968         return -1;
 969     }
 970     fprintf(f,
 971             "[global]\n"
 972             "private dir=%s\n"
 973             "interfaces=127.0.0.1\n"
 974             "bind interfaces only=yes\n"
 975             "pid directory=%s\n"
 976             "lock directory=%s\n"
 977             "state directory=%s\n"
 978             "cache directory=%s\n"
 979             "ncalrpc dir=%s/ncalrpc\n"
 980             "log file=%s/log.smbd\n"
 981             "smb passwd file=%s/smbpasswd\n"
 982             "security = user\n"
 983             "map to guest = Bad User\n"
 984             "load printers = no\n"
 985             "printing = bsd\n"
 986             "disable spoolss = yes\n"
 987             "usershare max shares = 0\n"
 988             "[qemu]\n"
 989             "path=%s\n"
 990             "read only=no\n"
 991             "guest ok=yes\n"
 992             "force user=%s\n",
 993             s->smb_dir,
 994             s->smb_dir,
 995             s->smb_dir,
 996             s->smb_dir,
 997             s->smb_dir,
 998             s->smb_dir,
 999             s->smb_dir,
1000             s->smb_dir,
1001             exported_dir,
1002             passwd->pw_name
1003             );
1004     fclose(f);
1005
1006     smb_cmdline = g_strdup_printf("%s -l %s -s %s",
1007              CONFIG_SMBD_COMMAND, s->smb_dir, smb_conf);
1008     g_free(smb_conf);
1009
1010     if (slirp_add_exec(s->slirp, smb_cmdline, &vserver_addr, 139) < 0 ||
1011         slirp_add_exec(s->slirp, smb_cmdline, &vserver_addr, 445) < 0) {
1012         slirp_smb_cleanup(s);
1013         g_free(smb_cmdline);
1014         error_setg(errp, "Conflicting/invalid smbserver address");
1015         return -1;
1016     }
1017     g_free(smb_cmdline);
1018     return 0;
1019 }
1020
1021 #endif /* defined(CONFIG_SMBD_COMMAND) */
1022
1023 static int guestfwd_can_read(void *opaque)
1024 {
1025     struct GuestFwd *fwd = opaque;
1026     return slirp_socket_can_recv(fwd->slirp, fwd->server, fwd->port);
1027 }
1028
1029 static void guestfwd_read(void *opaque, const uint8_t *buf, int size)
1030 {
1031     struct GuestFwd *fwd = opaque;
1032     slirp_socket_recv(fwd->slirp, fwd->server, fwd->port, buf, size);
1033 }
1034
1035 static ssize_t guestfwd_write(const void *buf, size_t len, void *chr)
1036 {
1037     return qemu_chr_fe_write_all(chr, buf, len);
1038 }
1039
1040 static int slirp_guestfwd(SlirpState *s, const char *config_str, Error **errp)
1041 {
1042     /* TODO: IPv6 */
1043     struct in_addr server = { .s_addr = 0 };
1044     struct GuestFwd *fwd;
1045     const char *p;
1046     char buf[128];
1047     char *end;
1048     int port;
1049
1050     p = config_str;
1051     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
1052         goto fail_syntax;
1053     }
1054     if (strcmp(buf, "tcp") && buf[0] != '\0') {
1055         goto fail_syntax;
1056     }
1057     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
1058         goto fail_syntax;
1059     }
1060     if (buf[0] != '\0' && !inet_aton(buf, &server)) {
1061         goto fail_syntax;
1062     }
1063     if (get_str_sep(buf, sizeof(buf), &p, '-') < 0) {
1064         goto fail_syntax;
1065     }
1066     port = strtol(buf, &end, 10);
1067     if (*end != '\0' || port < 1 || port > 65535) {
1068         goto fail_syntax;
1069     }
1070
1071     snprintf(buf, sizeof(buf), "guestfwd.tcp.%d", port);
1072
1073     if (g_str_has_prefix(p, "cmd:")) {
1074         if (slirp_add_exec(s->slirp, &p[4], &server, port) < 0) {
1075             error_setg(errp, "Conflicting/invalid host:port in guest "
1076                        "forwarding rule '%s'", config_str);
1077             return -1;
1078         }
1079     } else {
1080         Error *err = NULL;
1081         /*
1082          * FIXME: sure we want to support implicit
1083          * muxed monitors here?
1084          */
1085         Chardev *chr = qemu_chr_new_mux_mon(buf, p, NULL);
1086
1087         if (!chr) {
1088             error_setg(errp, "Could not open guest forwarding device '%s'",
1089                        buf);
1090             return -1;
1091         }
1092
1093         fwd = g_new(struct GuestFwd, 1);
1094         qemu_chr_fe_init(&fwd->hd, chr, &err);
1095         if (err) {
1096             error_propagate(errp, err);
1097             object_unparent(OBJECT(chr));
1098             g_free(fwd);
1099             return -1;
1100         }
1101
1102         if (slirp_add_guestfwd(s->slirp, guestfwd_write, &fwd->hd,
1103                                &server, port) < 0) {
1104             error_setg(errp, "Conflicting/invalid host:port in guest "
1105                        "forwarding rule '%s'", config_str);
1106             qemu_chr_fe_deinit(&fwd->hd, true);
1107             g_free(fwd);
1108             return -1;
1109         }
1110         fwd->server = server;
1111         fwd->port = port;
1112         fwd->slirp = s->slirp;
1113
1114         qemu_chr_fe_set_handlers(&fwd->hd, guestfwd_can_read, guestfwd_read,
1115                                  NULL, NULL, fwd, NULL, true);
1116         s->fwd = g_slist_append(s->fwd, fwd);
1117     }
1118     return 0;
1119
1120  fail_syntax:
1121     error_setg(errp, "Invalid guest forwarding rule '%s'", config_str);
1122     return -1;
1123 }
1124
1125 void hmp_info_usernet(Monitor *mon, const QDict *qdict)
1126 {
1127     SlirpState *s;
1128
1129     QTAILQ_FOREACH(s, &slirp_stacks, entry) {
1130         int id;
1131         bool got_hub_id = net_hub_id_for_client(&s->nc, &id) == 0;
1132         char *info = slirp_connection_info(s->slirp);
1133         monitor_printf(mon, "Hub %d (%s):\n%s",
1134                        got_hub_id ? id : -1,
1135                        s->nc.name, info);
1136         g_free(info);
1137     }
1138 }
1139
1140 static void
1141 net_init_slirp_configs(const StringList *fwd, int flags)
1142 {
1143     while (fwd) {
1144         struct slirp_config_str *config;
1145
1146         config = g_malloc0(sizeof(*config));
1147         pstrcpy(config->str, sizeof(config->str), fwd->value->str);
1148         config->flags = flags;
1149         config->next = slirp_configs;
1150         slirp_configs = config;
1151
1152         fwd = fwd->next;
1153     }
1154 }
1155
1156 static const char **slirp_dnssearch(const StringList *dnsname)
1157 {
1158     const StringList *c = dnsname;
1159     size_t i = 0, num_opts = 0;
1160     const char **ret;
1161
1162     while (c) {
1163         num_opts++;
1164         c = c->next;
1165     }
1166
1167     if (num_opts == 0) {
1168         return NULL;
1169     }
1170
1171     ret = g_malloc((num_opts + 1) * sizeof(*ret));
1172     c = dnsname;
1173     while (c) {
1174         ret[i++] = c->value->str;
1175         c = c->next;
1176     }
1177     ret[i] = NULL;
1178     return ret;
1179 }
1180
1181 int net_init_slirp(const Netdev *netdev, const char *name,
1182                    NetClientState *peer, Error **errp)
1183 {
1184     struct slirp_config_str *config;
1185     char *vnet;
1186     int ret;
1187     const NetdevUserOptions *user;
1188     const char **dnssearch;
1189     bool ipv4 = true, ipv6 = true;
1190
1191     assert(netdev->type == NET_CLIENT_DRIVER_USER);
1192     user = &netdev->u.user;
1193
1194     if ((user->has_ipv6 && user->ipv6 && !user->has_ipv4) ||
1195         (user->has_ipv4 && !user->ipv4)) {
1196         ipv4 = 0;
1197     }
1198     if ((user->has_ipv4 && user->ipv4 && !user->has_ipv6) ||
1199         (user->has_ipv6 && !user->ipv6)) {
1200         ipv6 = 0;
1201     }
1202
1203     vnet = user->net ? g_strdup(user->net) :
1204            user->ip  ? g_strdup_printf("%s/24", user->ip) :
1205            NULL;
1206
1207     dnssearch = slirp_dnssearch(user->dnssearch);
1208
1209     /* all optional fields are initialized to "all bits zero" */
1210
1211     net_init_slirp_configs(user->hostfwd, SLIRP_CFG_HOSTFWD);
1212     net_init_slirp_configs(user->guestfwd, 0);
1213
1214     ret = net_slirp_init(peer, "user", name, user->q_restrict,
1215                          ipv4, vnet, user->host,
1216                          ipv6, user->ipv6_prefix, user->ipv6_prefixlen,
1217                          user->ipv6_host, user->hostname, user->tftp,
1218                          user->bootfile, user->dhcpstart,
1219                          user->dns, user->ipv6_dns, user->smb,
1220                          user->smbserver, dnssearch, user->domainname,
1221                          user->tftp_server_name, errp);
1222
1223     while (slirp_configs) {
1224         config = slirp_configs;
1225         slirp_configs = config->next;
1226         g_free(config);
1227     }
1228
1229     g_free(vnet);
1230     g_free(dnssearch);
1231
1232     return ret;
1233 }