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