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 #ifndef _WIN32
  31 #include <pwd.h>
  32 #include <sys/wait.h>
  33 #endif
  34 #include "net/net.h"
  35 #include "clients.h"
  36 #include "hub.h"
  37 #include "monitor/monitor.h"
  38 #include "qemu/error-report.h"
  39 #include "qemu/sockets.h"
  40 #include <libslirp.h>
  41 #include "chardev/char-fe.h"
  42 #include "sysemu/sysemu.h"
  43 #include "qemu/cutils.h"
  44 #include "qapi/error.h"
  45 #include "qapi/qmp/qdict.h"
  46 #include "util.h"
  47 #include "migration/register.h"
  48 #include "migration/qemu-file-types.h"
  49
  50 static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
  51 {
  52     const char *p, *p1;
  53     int len;
  54     p = *pp;
  55     p1 = strchr(p, sep);
  56     if (!p1)
  57         return -1;
  58     len = p1 - p;
  59     p1++;
  60     if (buf_size > 0) {
  61         if (len > buf_size - 1)
  62             len = buf_size - 1;
  63         memcpy(buf, p, len);
  64         buf[len] = '\0';
  65     }
  66     *pp = p1;
  67     return 0;
  68 }
  69
  70 /* slirp network adapter */
  71
  72 #define SLIRP_CFG_HOSTFWD 1
  73
  74 struct slirp_config_str {
  75     struct slirp_config_str *next;
  76     int flags;
  77     char str[1024];
  78 };
  79
  80 struct GuestFwd {
  81     CharBackend hd;
  82     struct in_addr server;
  83     int port;
  84     Slirp *slirp;
  85 };
  86
  87 typedef struct SlirpState {
  88     NetClientState nc;
  89     QTAILQ_ENTRY(SlirpState) entry;
  90     Slirp *slirp;
  91     Notifier poll_notifier;
  92     Notifier exit_notifier;
  93 #ifndef _WIN32
  94     gchar *smb_dir;
  95 #endif
  96     GSList *fwd;
  97 } SlirpState;
  98
  99 static struct slirp_config_str *slirp_configs;
 100 static QTAILQ_HEAD(, SlirpState) slirp_stacks =
 101     QTAILQ_HEAD_INITIALIZER(slirp_stacks);
 102
 103 static int slirp_hostfwd(SlirpState *s, const char *redir_str, Error **errp);
 104 static int slirp_guestfwd(SlirpState *s, const char *config_str, Error **errp);
 105
 106 #ifndef _WIN32
 107 static int slirp_smb(SlirpState *s, const char *exported_dir,
 108                      struct in_addr vserver_addr, Error **errp);
 109 static void slirp_smb_cleanup(SlirpState *s);
 110 #else
 111 static inline void slirp_smb_cleanup(SlirpState *s) { }
 112 #endif
 113
 114 static ssize_t net_slirp_send_packet(const void *pkt, size_t pkt_len,
 115                                      void *opaque)
 116 {
 117     SlirpState *s = opaque;
 118
 119     return qemu_send_packet(&s->nc, pkt, pkt_len);
 120 }
 121
 122 static ssize_t net_slirp_receive(NetClientState *nc, const uint8_t *buf, size_t size)
 123 {
 124     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
 125
 126     slirp_input(s->slirp, buf, size);
 127
 128     return size;
 129 }
 130
 131 static void slirp_smb_exit(Notifier *n, void *data)
 132 {
 133     SlirpState *s = container_of(n, SlirpState, exit_notifier);
 134     slirp_smb_cleanup(s);
 135 }
 136
 137 static void slirp_free_fwd(gpointer data)
 138 {
 139     struct GuestFwd *fwd = data;
 140
 141     qemu_chr_fe_deinit(&fwd->hd, true);
 142     g_free(data);
 143 }
 144
 145 static void net_slirp_cleanup(NetClientState *nc)
 146 {
 147     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
 148
 149     g_slist_free_full(s->fwd, slirp_free_fwd);
 150     main_loop_poll_remove_notifier(&s->poll_notifier);
 151     unregister_savevm(NULL, "slirp", s->slirp);
 152     slirp_cleanup(s->slirp);
 153     if (s->exit_notifier.notify) {
 154         qemu_remove_exit_notifier(&s->exit_notifier);
 155     }
 156     slirp_smb_cleanup(s);
 157     QTAILQ_REMOVE(&slirp_stacks, s, entry);
 158 }
 159
 160 static NetClientInfo net_slirp_info = {
 161     .type = NET_CLIENT_DRIVER_USER,
 162     .size = sizeof(SlirpState),
 163     .receive = net_slirp_receive,
 164     .cleanup = net_slirp_cleanup,
 165 };
 166
 167 static void net_slirp_guest_error(const char *msg, void *opaque)
 168 {
 169     qemu_log_mask(LOG_GUEST_ERROR, "%s", msg);
 170 }
 171
 172 static int64_t net_slirp_clock_get_ns(void *opaque)
 173 {
 174     return qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
 175 }
 176
 177 static void *net_slirp_timer_new(SlirpTimerCb cb,
 178                                  void *cb_opaque, void *opaque)
 179 {
 180     return timer_new_full(NULL, QEMU_CLOCK_VIRTUAL,
 181                           SCALE_MS, QEMU_TIMER_ATTR_EXTERNAL,
 182                           cb, cb_opaque);
 183 }
 184
 185 static void net_slirp_timer_free(void *timer, void *opaque)
 186 {
 187     timer_free(timer);
 188 }
 189
 190 static void net_slirp_timer_mod(void *timer, int64_t expire_timer,
 191                                 void *opaque)
 192 {
 193     timer_mod(timer, expire_timer);
 194 }
 195
 196 static void net_slirp_register_poll_fd(int fd, void *opaque)
 197 {
 198     qemu_fd_register(fd);
 199 }
 200
 201 static void net_slirp_unregister_poll_fd(int fd, void *opaque)
 202 {
 203     /* no qemu_fd_unregister */
 204 }
 205
 206 static void net_slirp_notify(void *opaque)
 207 {
 208     qemu_notify_event();
 209 }
 210
 211 static const SlirpCb slirp_cb = {
 212     .send_packet = net_slirp_send_packet,
 213     .guest_error = net_slirp_guest_error,
 214     .clock_get_ns = net_slirp_clock_get_ns,
 215     .timer_new = net_slirp_timer_new,
 216     .timer_free = net_slirp_timer_free,
 217     .timer_mod = net_slirp_timer_mod,
 218     .register_poll_fd = net_slirp_register_poll_fd,
 219     .unregister_poll_fd = net_slirp_unregister_poll_fd,
 220     .notify = net_slirp_notify,
 221 };
 222
 223 static int slirp_poll_to_gio(int events)
 224 {
 225     int ret = 0;
 226
 227     if (events & SLIRP_POLL_IN) {
 228         ret |= G_IO_IN;
 229     }
 230     if (events & SLIRP_POLL_OUT) {
 231         ret |= G_IO_OUT;
 232     }
 233     if (events & SLIRP_POLL_PRI) {
 234         ret |= G_IO_PRI;
 235     }
 236     if (events & SLIRP_POLL_ERR) {
 237         ret |= G_IO_ERR;
 238     }
 239     if (events & SLIRP_POLL_HUP) {
 240         ret |= G_IO_HUP;
 241     }
 242
 243     return ret;
 244 }
 245
 246 static int net_slirp_add_poll(int fd, int events, void *opaque)
 247 {
 248     GArray *pollfds = opaque;
 249     GPollFD pfd = {
 250         .fd = fd,
 251         .events = slirp_poll_to_gio(events),
 252     };
 253     int idx = pollfds->len;
 254     g_array_append_val(pollfds, pfd);
 255     return idx;
 256 }
 257
 258 static int slirp_gio_to_poll(int events)
 259 {
 260     int ret = 0;
 261
 262     if (events & G_IO_IN) {
 263         ret |= SLIRP_POLL_IN;
 264     }
 265     if (events & G_IO_OUT) {
 266         ret |= SLIRP_POLL_OUT;
 267     }
 268     if (events & G_IO_PRI) {
 269         ret |= SLIRP_POLL_PRI;
 270     }
 271     if (events & G_IO_ERR) {
 272         ret |= SLIRP_POLL_ERR;
 273     }
 274     if (events & G_IO_HUP) {
 275         ret |= SLIRP_POLL_HUP;
 276     }
 277
 278     return ret;
 279 }
 280
 281 static int net_slirp_get_revents(int idx, void *opaque)
 282 {
 283     GArray *pollfds = opaque;
 284
 285     return slirp_gio_to_poll(g_array_index(pollfds, GPollFD, idx).revents);
 286 }
 287
 288 static void net_slirp_poll_notify(Notifier *notifier, void *data)
 289 {
 290     MainLoopPoll *poll = data;
 291     SlirpState *s = container_of(notifier, SlirpState, poll_notifier);
 292
 293     switch (poll->state) {
 294     case MAIN_LOOP_POLL_FILL:
 295         slirp_pollfds_fill(s->slirp, &poll->timeout,
 296                            net_slirp_add_poll, poll->pollfds);
 297         break;
 298     case MAIN_LOOP_POLL_OK:
 299     case MAIN_LOOP_POLL_ERR:
 300         slirp_pollfds_poll(s->slirp, poll->state == MAIN_LOOP_POLL_ERR,
 301                            net_slirp_get_revents, poll->pollfds);
 302         break;
 303     default:
 304         g_assert_not_reached();
 305     }
 306 }
 307
 308 static ssize_t
 309 net_slirp_stream_read(void *buf, size_t size, void *opaque)
 310 {
 311     QEMUFile *f = opaque;
 312
 313     return qemu_get_buffer(f, buf, size);
 314 }
 315
 316 static ssize_t
 317 net_slirp_stream_write(const void *buf, size_t size, void *opaque)
 318 {
 319     QEMUFile *f = opaque;
 320
 321     qemu_put_buffer(f, buf, size);
 322     if (qemu_file_get_error(f)) {
 323         return -1;
 324     }
 325
 326     return size;
 327 }
 328
 329 static int net_slirp_state_load(QEMUFile *f, void *opaque, int version_id)
 330 {
 331     Slirp *slirp = opaque;
 332
 333     return slirp_state_load(slirp, version_id, net_slirp_stream_read, f);
 334 }
 335
 336 static void net_slirp_state_save(QEMUFile *f, void *opaque)
 337 {
 338     Slirp *slirp = opaque;
 339
 340     slirp_state_save(slirp, net_slirp_stream_write, f);
 341 }
 342
 343 static SaveVMHandlers savevm_slirp_state = {
 344     .save_state = net_slirp_state_save,
 345     .load_state = net_slirp_state_load,
 346 };
 347
 348 static int net_slirp_init(NetClientState *peer, const char *model,
 349                           const char *name, int restricted,
 350                           bool ipv4, const char *vnetwork, const char *vhost,
 351                           bool ipv6, const char *vprefix6, int vprefix6_len,
 352                           const char *vhost6,
 353                           const char *vhostname, const char *tftp_export,
 354                           const char *bootfile, const char *vdhcp_start,
 355                           const char *vnameserver, const char *vnameserver6,
 356                           const char *smb_export, const char *vsmbserver,
 357                           const char **dnssearch, const char *vdomainname,
 358                           const char *tftp_server_name,
 359                           Error **errp)
 360 {
 361     /* default settings according to historic slirp */
 362     struct in_addr net  = { .s_addr = htonl(0x0a000200) }; /* 10.0.2.0 */
 363     struct in_addr mask = { .s_addr = htonl(0xffffff00) }; /* 255.255.255.0 */
 364     struct in_addr host = { .s_addr = htonl(0x0a000202) }; /* 10.0.2.2 */
 365     struct in_addr dhcp = { .s_addr = htonl(0x0a00020f) }; /* 10.0.2.15 */
 366     struct in_addr dns  = { .s_addr = htonl(0x0a000203) }; /* 10.0.2.3 */
 367     struct in6_addr ip6_prefix;
 368     struct in6_addr ip6_host;
 369     struct in6_addr ip6_dns;
 370 #ifndef _WIN32
 371     struct in_addr smbsrv = { .s_addr = 0 };
 372 #endif
 373     NetClientState *nc;
 374     SlirpState *s;
 375     char buf[20];
 376     uint32_t addr;
 377     int shift;
 378     char *end;
 379     struct slirp_config_str *config;
 380     NetdevUserOptions *stored;
 381     StringList **stored_hostfwd;
 382     StringList **stored_guestfwd;
 383
 384     if (!ipv4 && (vnetwork || vhost || vnameserver)) {
 385         error_setg(errp, "IPv4 disabled but netmask/host/dns provided");
 386         return -1;
 387     }
 388
 389     if (!ipv6 && (vprefix6 || vhost6 || vnameserver6)) {
 390         error_setg(errp, "IPv6 disabled but prefix/host6/dns6 provided");
 391         return -1;
 392     }
 393
 394     if (!ipv4 && !ipv6) {
 395         /* It doesn't make sense to disable both */
 396         error_setg(errp, "IPv4 and IPv6 disabled");
 397         return -1;
 398     }
 399
 400     if (vnetwork) {
 401         if (get_str_sep(buf, sizeof(buf), &vnetwork, '/') < 0) {
 402             if (!inet_aton(vnetwork, &net)) {
 403                 error_setg(errp, "Failed to parse netmask");
 404                 return -1;
 405             }
 406             addr = ntohl(net.s_addr);
 407             if (!(addr & 0x80000000)) {
 408                 mask.s_addr = htonl(0xff000000); /* class A */
 409             } else if ((addr & 0xfff00000) == 0xac100000) {
 410                 mask.s_addr = htonl(0xfff00000); /* priv. 172.16.0.0/12 */
 411             } else if ((addr & 0xc0000000) == 0x80000000) {
 412                 mask.s_addr = htonl(0xffff0000); /* class B */
 413             } else if ((addr & 0xffff0000) == 0xc0a80000) {
 414                 mask.s_addr = htonl(0xffff0000); /* priv. 192.168.0.0/16 */
 415             } else if ((addr & 0xffff0000) == 0xc6120000) {
 416                 mask.s_addr = htonl(0xfffe0000); /* tests 198.18.0.0/15 */
 417             } else if ((addr & 0xe0000000) == 0xe0000000) {
 418                 mask.s_addr = htonl(0xffffff00); /* class C */
 419             } else {
 420                 mask.s_addr = htonl(0xfffffff0); /* multicast/reserved */
 421             }
 422         } else {
 423             if (!inet_aton(buf, &net)) {
 424                 error_setg(errp, "Failed to parse netmask");
 425                 return -1;
 426             }
 427             shift = strtol(vnetwork, &end, 10);
 428             if (*end != '\0') {
 429                 if (!inet_aton(vnetwork, &mask)) {
 430                     error_setg(errp,
 431                                "Failed to parse netmask (trailing chars)");
 432                     return -1;
 433                 }
 434             } else if (shift < 4 || shift > 32) {
 435                 error_setg(errp,
 436                            "Invalid netmask provided (must be in range 4-32)");
 437                 return -1;
 438             } else {
 439                 mask.s_addr = htonl(0xffffffff << (32 - shift));
 440             }
 441         }
 442         net.s_addr &= mask.s_addr;
 443         host.s_addr = net.s_addr | (htonl(0x0202) & ~mask.s_addr);
 444         dhcp.s_addr = net.s_addr | (htonl(0x020f) & ~mask.s_addr);
 445         dns.s_addr  = net.s_addr | (htonl(0x0203) & ~mask.s_addr);
 446     }
 447
 448     if (vhost && !inet_aton(vhost, &host)) {
 449         error_setg(errp, "Failed to parse host");
 450         return -1;
 451     }
 452     if ((host.s_addr & mask.s_addr) != net.s_addr) {
 453         error_setg(errp, "Host doesn't belong to network");
 454         return -1;
 455     }
 456
 457     if (vnameserver && !inet_aton(vnameserver, &dns)) {
 458         error_setg(errp, "Failed to parse DNS");
 459         return -1;
 460     }
 461     if (restricted && (dns.s_addr & mask.s_addr) != net.s_addr) {
 462         error_setg(errp, "DNS doesn't belong to network");
 463         return -1;
 464     }
 465     if (dns.s_addr == host.s_addr) {
 466         error_setg(errp, "DNS must be different from host");
 467         return -1;
 468     }
 469
 470     if (vdhcp_start && !inet_aton(vdhcp_start, &dhcp)) {
 471         error_setg(errp, "Failed to parse DHCP start address");
 472         return -1;
 473     }
 474     if ((dhcp.s_addr & mask.s_addr) != net.s_addr) {
 475         error_setg(errp, "DHCP doesn't belong to network");
 476         return -1;
 477     }
 478     if (dhcp.s_addr == host.s_addr || dhcp.s_addr == dns.s_addr) {
 479         error_setg(errp, "DHCP must be different from host and DNS");
 480         return -1;
 481     }
 482
 483 #ifndef _WIN32
 484     if (vsmbserver && !inet_aton(vsmbserver, &smbsrv)) {
 485         error_setg(errp, "Failed to parse SMB address");
 486         return -1;
 487     }
 488 #endif
 489
 490     if (!vprefix6) {
 491         vprefix6 = "fec0::";
 492     }
 493     if (!inet_pton(AF_INET6, vprefix6, &ip6_prefix)) {
 494         error_setg(errp, "Failed to parse IPv6 prefix");
 495         return -1;
 496     }
 497
 498     if (!vprefix6_len) {
 499         vprefix6_len = 64;
 500     }
 501     if (vprefix6_len < 0 || vprefix6_len > 126) {
 502         error_setg(errp,
 503                    "Invalid IPv6 prefix provided "
 504                    "(IPv6 prefix length must be between 0 and 126)");
 505         return -1;
 506     }
 507
 508     if (vhost6) {
 509         if (!inet_pton(AF_INET6, vhost6, &ip6_host)) {
 510             error_setg(errp, "Failed to parse IPv6 host");
 511             return -1;
 512         }
 513         if (!in6_equal_net(&ip6_prefix, &ip6_host, vprefix6_len)) {
 514             error_setg(errp, "IPv6 Host doesn't belong to network");
 515             return -1;
 516         }
 517     } else {
 518         ip6_host = ip6_prefix;
 519         ip6_host.s6_addr[15] |= 2;
 520     }
 521
 522     if (vnameserver6) {
 523         if (!inet_pton(AF_INET6, vnameserver6, &ip6_dns)) {
 524             error_setg(errp, "Failed to parse IPv6 DNS");
 525             return -1;
 526         }
 527         if (restricted && !in6_equal_net(&ip6_prefix, &ip6_dns, vprefix6_len)) {
 528             error_setg(errp, "IPv6 DNS doesn't belong to network");
 529             return -1;
 530         }
 531     } else {
 532         ip6_dns = ip6_prefix;
 533         ip6_dns.s6_addr[15] |= 3;
 534     }
 535
 536     if (vdomainname && !*vdomainname) {
 537         error_setg(errp, "'domainname' parameter cannot be empty");
 538         return -1;
 539     }
 540
 541     if (vdomainname && strlen(vdomainname) > 255) {
 542         error_setg(errp, "'domainname' parameter cannot exceed 255 bytes");
 543         return -1;
 544     }
 545
 546     if (vhostname && strlen(vhostname) > 255) {
 547         error_setg(errp, "'vhostname' parameter cannot exceed 255 bytes");
 548         return -1;
 549     }
 550
 551     if (tftp_server_name && strlen(tftp_server_name) > 255) {
 552         error_setg(errp, "'tftp-server-name' parameter cannot exceed 255 bytes");
 553         return -1;
 554     }
 555
 556     nc = qemu_new_net_client(&net_slirp_info, peer, model, name);
 557
 558     /* Store startup parameters */
 559     nc->stored_config = g_new0(NetdevInfo, 1);
 560     nc->stored_config->type = NET_BACKEND_USER;
 561     stored = &nc->stored_config->u.user;
 562
 563     if (vhostname) {
 564         stored->has_hostname = true;
 565         stored->hostname = g_strdup(vhostname);
 566     }
 567
 568     stored->has_q_restrict = true;
 569     stored->q_restrict = restricted;
 570
 571     stored->has_ipv4 = true;
 572     stored->ipv4 = ipv4;
 573
 574     stored->has_ipv6 = true;
 575     stored->ipv6 = ipv6;
 576
 577     if (ipv4) {
 578         uint8_t *net_bytes = (uint8_t *)&net;
 579         uint8_t *mask_bytes = (uint8_t *)&mask;
 580
 581         stored->has_net = true;
 582         stored->net = g_strdup_printf("%d.%d.%d.%d/%d.%d.%d.%d",
 583                                       net_bytes[0], net_bytes[1],
 584                                       net_bytes[2], net_bytes[3],
 585                                       mask_bytes[0], mask_bytes[1],
 586                                       mask_bytes[2], mask_bytes[3]);
 587
 588         stored->has_host = true;
 589         stored->host = g_strdup(inet_ntoa(host));
 590     }
 591
 592     if (tftp_export) {
 593         stored->has_tftp = true;
 594         stored->tftp = g_strdup(tftp_export);
 595     }
 596
 597     if (bootfile) {
 598         stored->has_bootfile = true;
 599         stored->bootfile = g_strdup(bootfile);
 600     }
 601
 602     if (vdhcp_start) {
 603         stored->has_dhcpstart = true;
 604         stored->dhcpstart = g_strdup(vdhcp_start);
 605     }
 606
 607     if (ipv4) {
 608         stored->has_dns = true;
 609         stored->dns = g_strdup(inet_ntoa(dns));
 610     }
 611
 612     if (dnssearch) {
 613         stored->has_dnssearch = true;
 614         StringList **stored_list = &stored->dnssearch;
 615
 616         for (int i = 0; dnssearch[i]; i++) {
 617             String *element = g_new0(String, 1);
 618
 619             element->str = g_strdup(dnssearch[i]);
 620             QAPI_LIST_APPEND(stored_list, element);
 621         }
 622     }
 623
 624     if (vdomainname) {
 625         stored->has_domainname = true;
 626         stored->domainname = g_strdup(vdomainname);
 627     }
 628
 629     if (ipv6) {
 630         char addrstr[INET6_ADDRSTRLEN];
 631         const char *res;
 632
 633         stored->has_ipv6_prefix = true;
 634         stored->ipv6_prefix = g_strdup(vprefix6);
 635
 636         stored->has_ipv6_prefixlen = true;
 637         stored->ipv6_prefixlen = vprefix6_len;
 638
 639         res = inet_ntop(AF_INET6, &ip6_host,
 640                         addrstr, sizeof(addrstr));
 641
 642         stored->has_ipv6_host = true;
 643         stored->ipv6_host = g_strdup(res);
 644
 645         res = inet_ntop(AF_INET6, &ip6_dns,
 646                         addrstr, sizeof(addrstr));
 647
 648         stored->has_ipv6_dns = true;
 649         stored->ipv6_dns = g_strdup(res);
 650     }
 651
 652     if (smb_export) {
 653         stored->has_smb = true;
 654         stored->smb = g_strdup(smb_export);
 655     }
 656
 657     if (vsmbserver) {
 658         stored->has_smbserver = true;
 659         stored->smbserver = g_strdup(vsmbserver);
 660     }
 661
 662     if (tftp_server_name) {
 663         stored->has_tftp_server_name = true;
 664         stored->tftp_server_name = g_strdup(tftp_server_name);
 665     }
 666
 667     s = DO_UPCAST(SlirpState, nc, nc);
 668
 669     s->slirp = slirp_init(restricted, ipv4, net, mask, host,
 670                           ipv6, ip6_prefix, vprefix6_len, ip6_host,
 671                           vhostname, tftp_server_name,
 672                           tftp_export, bootfile, dhcp,
 673                           dns, ip6_dns, dnssearch, vdomainname,
 674                           &slirp_cb, s);
 675     QTAILQ_INSERT_TAIL(&slirp_stacks, s, entry);
 676
 677     /*
 678      * Make sure the current bitstream version of slirp is 4, to avoid
 679      * QEMU migration incompatibilities, if upstream slirp bumped the
 680      * version.
 681      *
 682      * FIXME: use bitfields of features? teach libslirp to save with
 683      * specific version?
 684      */
 685     g_assert(slirp_state_version() == 4);
 686     register_savevm_live("slirp", 0, slirp_state_version(),
 687                          &savevm_slirp_state, s->slirp);
 688
 689     s->poll_notifier.notify = net_slirp_poll_notify;
 690     main_loop_poll_add_notifier(&s->poll_notifier);
 691
 692     stored_hostfwd = &stored->hostfwd;
 693     stored_guestfwd = &stored->guestfwd;
 694
 695     for (config = slirp_configs; config; config = config->next) {
 696         String *element = g_new0(String, 1);
 697
 698         element->str = g_strdup(config->str);
 699         if (config->flags & SLIRP_CFG_HOSTFWD) {
 700             if (slirp_hostfwd(s, config->str, errp) < 0) {
 701                 goto error;
 702             }
 703             stored->has_hostfwd = true;
 704             QAPI_LIST_APPEND(stored_hostfwd, element);
 705         } else {
 706             if (slirp_guestfwd(s, config->str, errp) < 0) {
 707                 goto error;
 708             }
 709             stored->has_guestfwd = true;
 710             QAPI_LIST_APPEND(stored_guestfwd, element);
 711         }
 712     }
 713 #ifndef _WIN32
 714     if (smb_export) {
 715         if (slirp_smb(s, smb_export, smbsrv, errp) < 0) {
 716             goto error;
 717         }
 718     }
 719 #endif
 720
 721     s->exit_notifier.notify = slirp_smb_exit;
 722     qemu_add_exit_notifier(&s->exit_notifier);
 723     return 0;
 724
 725 error:
 726     qemu_del_net_client(nc);
 727     return -1;
 728 }
 729
 730 static SlirpState *slirp_lookup(Monitor *mon, const char *id)
 731 {
 732     if (id) {
 733         NetClientState *nc = qemu_find_netdev(id);
 734         if (!nc) {
 735             monitor_printf(mon, "unrecognized netdev id '%s'\n", id);
 736             return NULL;
 737         }
 738         if (strcmp(nc->model, "user")) {
 739             monitor_printf(mon, "invalid device specified\n");
 740             return NULL;
 741         }
 742         return DO_UPCAST(SlirpState, nc, nc);
 743     } else {
 744         if (QTAILQ_EMPTY(&slirp_stacks)) {
 745             monitor_printf(mon, "user mode network stack not in use\n");
 746             return NULL;
 747         }
 748         return QTAILQ_FIRST(&slirp_stacks);
 749     }
 750 }
 751
 752 void hmp_hostfwd_remove(Monitor *mon, const QDict *qdict)
 753 {
 754     struct in_addr host_addr = { .s_addr = INADDR_ANY };
 755     int host_port;
 756     char buf[256];
 757     const char *src_str, *p;
 758     SlirpState *s;
 759     int is_udp = 0;
 760     int err;
 761     const char *arg1 = qdict_get_str(qdict, "arg1");
 762     const char *arg2 = qdict_get_try_str(qdict, "arg2");
 763
 764     if (arg2) {
 765         s = slirp_lookup(mon, arg1);
 766         src_str = arg2;
 767     } else {
 768         s = slirp_lookup(mon, NULL);
 769         src_str = arg1;
 770     }
 771     if (!s) {
 772         return;
 773     }
 774
 775     p = src_str;
 776     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 777         goto fail_syntax;
 778     }
 779
 780     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
 781         is_udp = 0;
 782     } else if (!strcmp(buf, "udp")) {
 783         is_udp = 1;
 784     } else {
 785         goto fail_syntax;
 786     }
 787
 788     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 789         goto fail_syntax;
 790     }
 791     if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
 792         goto fail_syntax;
 793     }
 794
 795     if (qemu_strtoi(p, NULL, 10, &host_port)) {
 796         goto fail_syntax;
 797     }
 798
 799     err = slirp_remove_hostfwd(s->slirp, is_udp, host_addr, host_port);
 800
 801     monitor_printf(mon, "host forwarding rule for %s %s\n", src_str,
 802                    err ? "not found" : "removed");
 803     return;
 804
 805  fail_syntax:
 806     monitor_printf(mon, "invalid format\n");
 807 }
 808
 809 static int slirp_hostfwd(SlirpState *s, const char *redir_str, Error **errp)
 810 {
 811     struct in_addr host_addr = { .s_addr = INADDR_ANY };
 812     struct in_addr guest_addr = { .s_addr = 0 };
 813     int host_port, guest_port;
 814     const char *p;
 815     char buf[256];
 816     int is_udp;
 817     char *end;
 818     const char *fail_reason = "Unknown reason";
 819
 820     p = redir_str;
 821     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 822         fail_reason = "No : separators";
 823         goto fail_syntax;
 824     }
 825     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
 826         is_udp = 0;
 827     } else if (!strcmp(buf, "udp")) {
 828         is_udp = 1;
 829     } else {
 830         fail_reason = "Bad protocol name";
 831         goto fail_syntax;
 832     }
 833
 834     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 835         fail_reason = "Missing : separator";
 836         goto fail_syntax;
 837     }
 838     if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
 839         fail_reason = "Bad host address";
 840         goto fail_syntax;
 841     }
 842
 843     if (get_str_sep(buf, sizeof(buf), &p, '-') < 0) {
 844         fail_reason = "Bad host port separator";
 845         goto fail_syntax;
 846     }
 847     host_port = strtol(buf, &end, 0);
 848     if (*end != '\0' || host_port < 0 || host_port > 65535) {
 849         fail_reason = "Bad host port";
 850         goto fail_syntax;
 851     }
 852
 853     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 854         fail_reason = "Missing guest address";
 855         goto fail_syntax;
 856     }
 857     if (buf[0] != '\0' && !inet_aton(buf, &guest_addr)) {
 858         fail_reason = "Bad guest address";
 859         goto fail_syntax;
 860     }
 861
 862     guest_port = strtol(p, &end, 0);
 863     if (*end != '\0' || guest_port < 1 || guest_port > 65535) {
 864         fail_reason = "Bad guest port";
 865         goto fail_syntax;
 866     }
 867
 868     if (slirp_add_hostfwd(s->slirp, is_udp, host_addr, host_port, guest_addr,
 869                           guest_port) < 0) {
 870         error_setg(errp, "Could not set up host forwarding rule '%s'",
 871                    redir_str);
 872         return -1;
 873     }
 874     return 0;
 875
 876  fail_syntax:
 877     error_setg(errp, "Invalid host forwarding rule '%s' (%s)", redir_str,
 878                fail_reason);
 879     return -1;
 880 }
 881
 882 void hmp_hostfwd_add(Monitor *mon, const QDict *qdict)
 883 {
 884     const char *redir_str;
 885     SlirpState *s;
 886     const char *arg1 = qdict_get_str(qdict, "arg1");
 887     const char *arg2 = qdict_get_try_str(qdict, "arg2");
 888
 889     if (arg2) {
 890         s = slirp_lookup(mon, arg1);
 891         redir_str = arg2;
 892     } else {
 893         s = slirp_lookup(mon, NULL);
 894         redir_str = arg1;
 895     }
 896     if (s) {
 897         Error *err = NULL;
 898         if (slirp_hostfwd(s, redir_str, &err) < 0) {
 899             error_report_err(err);
 900         }
 901     }
 902
 903 }
 904
 905 #ifndef _WIN32
 906
 907 /* automatic user mode samba server configuration */
 908 static void slirp_smb_cleanup(SlirpState *s)
 909 {
 910     int ret;
 911
 912     if (s->smb_dir) {
 913         gchar *cmd = g_strdup_printf("rm -rf %s", s->smb_dir);
 914         ret = system(cmd);
 915         if (ret == -1 || !WIFEXITED(ret)) {
 916             error_report("'%s' failed.", cmd);
 917         } else if (WEXITSTATUS(ret)) {
 918             error_report("'%s' failed. Error code: %d",
 919                          cmd, WEXITSTATUS(ret));
 920         }
 921         g_free(cmd);
 922         g_free(s->smb_dir);
 923         s->smb_dir = NULL;
 924     }
 925 }
 926
 927 static int slirp_smb(SlirpState* s, const char *exported_dir,
 928                      struct in_addr vserver_addr, Error **errp)
 929 {
 930     char *smb_conf;
 931     char *smb_cmdline;
 932     struct passwd *passwd;
 933     FILE *f;
 934
 935     passwd = getpwuid(geteuid());
 936     if (!passwd) {
 937         error_setg(errp, "Failed to retrieve user name");
 938         return -1;
 939     }
 940
 941     if (access(CONFIG_SMBD_COMMAND, F_OK)) {
 942         error_setg(errp, "Could not find '%s', please install it",
 943                    CONFIG_SMBD_COMMAND);
 944         return -1;
 945     }
 946
 947     if (access(exported_dir, R_OK | X_OK)) {
 948         error_setg(errp, "Error accessing shared directory '%s': %s",
 949                    exported_dir, strerror(errno));
 950         return -1;
 951     }
 952
 953     s->smb_dir = g_dir_make_tmp("qemu-smb.XXXXXX", NULL);
 954     if (!s->smb_dir) {
 955         error_setg(errp, "Could not create samba server dir");
 956         return -1;
 957     }
 958     smb_conf = g_strdup_printf("%s/%s", s->smb_dir, "smb.conf");
 959
 960     f = fopen(smb_conf, "w");
 961     if (!f) {
 962         slirp_smb_cleanup(s);
 963         error_setg(errp,
 964                    "Could not create samba server configuration file '%s'",
 965                     smb_conf);
 966         g_free(smb_conf);
 967         return -1;
 968     }
 969     fprintf(f,
 970             "[global]\n"
 971             "private dir=%s\n"
 972             "interfaces=127.0.0.1\n"
 973             "bind interfaces only=yes\n"
 974             "pid directory=%s\n"
 975             "lock directory=%s\n"
 976             "state directory=%s\n"
 977             "cache directory=%s\n"
 978             "ncalrpc dir=%s/ncalrpc\n"
 979             "log file=%s/log.smbd\n"
 980             "smb passwd file=%s/smbpasswd\n"
 981             "security = user\n"
 982             "map to guest = Bad User\n"
 983             "load printers = no\n"
 984             "printing = bsd\n"
 985             "disable spoolss = yes\n"
 986             "usershare max shares = 0\n"
 987             "[qemu]\n"
 988             "path=%s\n"
 989             "read only=no\n"
 990             "guest ok=yes\n"
 991             "force user=%s\n",
 992             s->smb_dir,
 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             exported_dir,
1001             passwd->pw_name
1002             );
1003     fclose(f);
1004
1005     smb_cmdline = g_strdup_printf("%s -l %s -s %s",
1006              CONFIG_SMBD_COMMAND, s->smb_dir, smb_conf);
1007     g_free(smb_conf);
1008
1009     if (slirp_add_exec(s->slirp, smb_cmdline, &vserver_addr, 139) < 0 ||
1010         slirp_add_exec(s->slirp, smb_cmdline, &vserver_addr, 445) < 0) {
1011         slirp_smb_cleanup(s);
1012         g_free(smb_cmdline);
1013         error_setg(errp, "Conflicting/invalid smbserver address");
1014         return -1;
1015     }
1016     g_free(smb_cmdline);
1017     return 0;
1018 }
1019
1020 #endif /* !defined(_WIN32) */
1021
1022 static int guestfwd_can_read(void *opaque)
1023 {
1024     struct GuestFwd *fwd = opaque;
1025     return slirp_socket_can_recv(fwd->slirp, fwd->server, fwd->port);
1026 }
1027
1028 static void guestfwd_read(void *opaque, const uint8_t *buf, int size)
1029 {
1030     struct GuestFwd *fwd = opaque;
1031     slirp_socket_recv(fwd->slirp, fwd->server, fwd->port, buf, size);
1032 }
1033
1034 static ssize_t guestfwd_write(const void *buf, size_t len, void *chr)
1035 {
1036     return qemu_chr_fe_write_all(chr, buf, len);
1037 }
1038
1039 static int slirp_guestfwd(SlirpState *s, const char *config_str, Error **errp)
1040 {
1041     /* TODO: IPv6 */
1042     struct in_addr server = { .s_addr = 0 };
1043     struct GuestFwd *fwd;
1044     const char *p;
1045     char buf[128];
1046     char *end;
1047     int port;
1048
1049     p = config_str;
1050     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
1051         goto fail_syntax;
1052     }
1053     if (strcmp(buf, "tcp") && buf[0] != '\0') {
1054         goto fail_syntax;
1055     }
1056     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
1057         goto fail_syntax;
1058     }
1059     if (buf[0] != '\0' && !inet_aton(buf, &server)) {
1060         goto fail_syntax;
1061     }
1062     if (get_str_sep(buf, sizeof(buf), &p, '-') < 0) {
1063         goto fail_syntax;
1064     }
1065     port = strtol(buf, &end, 10);
1066     if (*end != '\0' || port < 1 || port > 65535) {
1067         goto fail_syntax;
1068     }
1069
1070     snprintf(buf, sizeof(buf), "guestfwd.tcp.%d", port);
1071
1072     if (g_str_has_prefix(p, "cmd:")) {
1073         if (slirp_add_exec(s->slirp, &p[4], &server, port) < 0) {
1074             error_setg(errp, "Conflicting/invalid host:port in guest "
1075                        "forwarding rule '%s'", config_str);
1076             return -1;
1077         }
1078     } else {
1079         Error *err = NULL;
1080         /*
1081          * FIXME: sure we want to support implicit
1082          * muxed monitors here?
1083          */
1084         Chardev *chr = qemu_chr_new_mux_mon(buf, p, NULL);
1085
1086         if (!chr) {
1087             error_setg(errp, "Could not open guest forwarding device '%s'",
1088                        buf);
1089             return -1;
1090         }
1091
1092         fwd = g_new(struct GuestFwd, 1);
1093         qemu_chr_fe_init(&fwd->hd, chr, &err);
1094         if (err) {
1095             error_propagate(errp, err);
1096             object_unparent(OBJECT(chr));
1097             g_free(fwd);
1098             return -1;
1099         }
1100
1101         if (slirp_add_guestfwd(s->slirp, guestfwd_write, &fwd->hd,
1102                                &server, port) < 0) {
1103             error_setg(errp, "Conflicting/invalid host:port in guest "
1104                        "forwarding rule '%s'", config_str);
1105             qemu_chr_fe_deinit(&fwd->hd, true);
1106             g_free(fwd);
1107             return -1;
1108         }
1109         fwd->server = server;
1110         fwd->port = port;
1111         fwd->slirp = s->slirp;
1112
1113         qemu_chr_fe_set_handlers(&fwd->hd, guestfwd_can_read, guestfwd_read,
1114                                  NULL, NULL, fwd, NULL, true);
1115         s->fwd = g_slist_append(s->fwd, fwd);
1116     }
1117     return 0;
1118
1119  fail_syntax:
1120     error_setg(errp, "Invalid guest forwarding rule '%s'", config_str);
1121     return -1;
1122 }
1123
1124 void hmp_info_usernet(Monitor *mon, const QDict *qdict)
1125 {
1126     SlirpState *s;
1127
1128     QTAILQ_FOREACH(s, &slirp_stacks, entry) {
1129         int id;
1130         bool got_hub_id = net_hub_id_for_client(&s->nc, &id) == 0;
1131         char *info = slirp_connection_info(s->slirp);
1132         monitor_printf(mon, "Hub %d (%s):\n%s",
1133                        got_hub_id ? id : -1,
1134                        s->nc.name, info);
1135         g_free(info);
1136     }
1137 }
1138
1139 static void
1140 net_init_slirp_configs(const StringList *fwd, int flags)
1141 {
1142     while (fwd) {
1143         struct slirp_config_str *config;
1144
1145         config = g_malloc0(sizeof(*config));
1146         pstrcpy(config->str, sizeof(config->str), fwd->value->str);
1147         config->flags = flags;
1148         config->next = slirp_configs;
1149         slirp_configs = config;
1150
1151         fwd = fwd->next;
1152     }
1153 }
1154
1155 static const char **slirp_dnssearch(const StringList *dnsname)
1156 {
1157     const StringList *c = dnsname;
1158     size_t i = 0, num_opts = 0;
1159     const char **ret;
1160
1161     while (c) {
1162         num_opts++;
1163         c = c->next;
1164     }
1165
1166     if (num_opts == 0) {
1167         return NULL;
1168     }
1169
1170     ret = g_malloc((num_opts + 1) * sizeof(*ret));
1171     c = dnsname;
1172     while (c) {
1173         ret[i++] = c->value->str;
1174         c = c->next;
1175     }
1176     ret[i] = NULL;
1177     return ret;
1178 }
1179
1180 int net_init_slirp(const Netdev *netdev, const char *name,
1181                    NetClientState *peer, Error **errp)
1182 {
1183     struct slirp_config_str *config;
1184     char *vnet;
1185     int ret;
1186     const NetdevUserOptions *user;
1187     const char **dnssearch;
1188     bool ipv4 = true, ipv6 = true;
1189
1190     assert(netdev->type == NET_CLIENT_DRIVER_USER);
1191     user = &netdev->u.user;
1192
1193     if ((user->has_ipv6 && user->ipv6 && !user->has_ipv4) ||
1194         (user->has_ipv4 && !user->ipv4)) {
1195         ipv4 = 0;
1196     }
1197     if ((user->has_ipv4 && user->ipv4 && !user->has_ipv6) ||
1198         (user->has_ipv6 && !user->ipv6)) {
1199         ipv6 = 0;
1200     }
1201
1202     vnet = user->has_net ? g_strdup(user->net) :
1203            user->has_ip  ? g_strdup_printf("%s/24", user->ip) :
1204            NULL;
1205
1206     dnssearch = slirp_dnssearch(user->dnssearch);
1207
1208     /* all optional fields are initialized to "all bits zero" */
1209
1210     net_init_slirp_configs(user->hostfwd, SLIRP_CFG_HOSTFWD);
1211     net_init_slirp_configs(user->guestfwd, 0);
1212
1213     ret = net_slirp_init(peer, "user", name, user->q_restrict,
1214                          ipv4, vnet, user->host,
1215                          ipv6, user->ipv6_prefix, user->ipv6_prefixlen,
1216                          user->ipv6_host, user->hostname, user->tftp,
1217                          user->bootfile, user->dhcpstart,
1218                          user->dns, user->ipv6_dns, user->smb,
1219                          user->smbserver, dnssearch, user->domainname,
1220                          user->tftp_server_name, errp);
1221
1222     while (slirp_configs) {
1223         config = slirp_configs;
1224         slirp_configs = config->next;
1225         g_free(config);
1226     }
1227
1228     g_free(vnet);
1229     g_free(dnssearch);
1230
1231     return ret;
1232 }