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