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 #include "qemu/osdep.h"
  25 #include "net/slirp.h"
  26
  27
  28 #ifndef _WIN32
  29 #include <pwd.h>
  30 #include <sys/wait.h>
  31 #endif
  32 #include "net/net.h"
  33 #include "clients.h"
  34 #include "hub.h"
  35 #include "monitor/monitor.h"
  36 #include "qemu/error-report.h"
  37 #include "qemu/sockets.h"
  38 #include "slirp/libslirp.h"
  39 #include "slirp/ip6.h"
  40 #include "chardev/char-fe.h"
  41 #include "sysemu/sysemu.h"
  42 #include "qemu/cutils.h"
  43 #include "qapi/error.h"
  44
  45 static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
  46 {
  47     const char *p, *p1;
  48     int len;
  49     p = *pp;
  50     p1 = strchr(p, sep);
  51     if (!p1)
  52         return -1;
  53     len = p1 - p;
  54     p1++;
  55     if (buf_size > 0) {
  56         if (len > buf_size - 1)
  57             len = buf_size - 1;
  58         memcpy(buf, p, len);
  59         buf[len] = '\0';
  60     }
  61     *pp = p1;
  62     return 0;
  63 }
  64
  65 /* slirp network adapter */
  66
  67 #define SLIRP_CFG_HOSTFWD 1
  68 #define SLIRP_CFG_LEGACY  2
  69
  70 struct slirp_config_str {
  71     struct slirp_config_str *next;
  72     int flags;
  73     char str[1024];
  74     int legacy_format;
  75 };
  76
  77 typedef struct SlirpState {
  78     NetClientState nc;
  79     QTAILQ_ENTRY(SlirpState) entry;
  80     Slirp *slirp;
  81     Notifier exit_notifier;
  82 #ifndef _WIN32
  83     gchar *smb_dir;
  84 #endif
  85 } SlirpState;
  86
  87 static struct slirp_config_str *slirp_configs;
  88 const char *legacy_tftp_prefix;
  89 const char *legacy_bootp_filename;
  90 static QTAILQ_HEAD(slirp_stacks, SlirpState) slirp_stacks =
  91     QTAILQ_HEAD_INITIALIZER(slirp_stacks);
  92
  93 static int slirp_hostfwd(SlirpState *s, const char *redir_str,
  94                          int legacy_format, Error **errp);
  95 static int slirp_guestfwd(SlirpState *s, const char *config_str,
  96                           int legacy_format, Error **errp);
  97
  98 #ifndef _WIN32
  99 static const char *legacy_smb_export;
 100
 101 static int slirp_smb(SlirpState *s, const char *exported_dir,
 102                      struct in_addr vserver_addr, Error **errp);
 103 static void slirp_smb_cleanup(SlirpState *s);
 104 #else
 105 static inline void slirp_smb_cleanup(SlirpState *s) { }
 106 #endif
 107
 108 void slirp_output(void *opaque, const uint8_t *pkt, int pkt_len)
 109 {
 110     SlirpState *s = opaque;
 111
 112     qemu_send_packet(&s->nc, pkt, pkt_len);
 113 }
 114
 115 static ssize_t net_slirp_receive(NetClientState *nc, const uint8_t *buf, size_t size)
 116 {
 117     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
 118
 119     slirp_input(s->slirp, buf, size);
 120
 121     return size;
 122 }
 123
 124 static void slirp_smb_exit(Notifier *n, void *data)
 125 {
 126     SlirpState *s = container_of(n, SlirpState, exit_notifier);
 127     slirp_smb_cleanup(s);
 128 }
 129
 130 static void net_slirp_cleanup(NetClientState *nc)
 131 {
 132     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
 133
 134     slirp_cleanup(s->slirp);
 135     if (s->exit_notifier.notify) {
 136         qemu_remove_exit_notifier(&s->exit_notifier);
 137     }
 138     slirp_smb_cleanup(s);
 139     QTAILQ_REMOVE(&slirp_stacks, s, entry);
 140 }
 141
 142 static NetClientInfo net_slirp_info = {
 143     .type = NET_CLIENT_DRIVER_USER,
 144     .size = sizeof(SlirpState),
 145     .receive = net_slirp_receive,
 146     .cleanup = net_slirp_cleanup,
 147 };
 148
 149 static int net_slirp_init(NetClientState *peer, const char *model,
 150                           const char *name, int restricted,
 151                           bool ipv4, const char *vnetwork, const char *vhost,
 152                           bool ipv6, const char *vprefix6, int vprefix6_len,
 153                           const char *vhost6,
 154                           const char *vhostname, const char *tftp_export,
 155                           const char *bootfile, const char *vdhcp_start,
 156                           const char *vnameserver, const char *vnameserver6,
 157                           const char *smb_export, const char *vsmbserver,
 158                           const char **dnssearch, Error **errp)
 159 {
 160     /* default settings according to historic slirp */
 161     struct in_addr net  = { .s_addr = htonl(0x0a000200) }; /* 10.0.2.0 */
 162     struct in_addr mask = { .s_addr = htonl(0xffffff00) }; /* 255.255.255.0 */
 163     struct in_addr host = { .s_addr = htonl(0x0a000202) }; /* 10.0.2.2 */
 164     struct in_addr dhcp = { .s_addr = htonl(0x0a00020f) }; /* 10.0.2.15 */
 165     struct in_addr dns  = { .s_addr = htonl(0x0a000203) }; /* 10.0.2.3 */
 166     struct in6_addr ip6_prefix;
 167     struct in6_addr ip6_host;
 168     struct in6_addr ip6_dns;
 169 #ifndef _WIN32
 170     struct in_addr smbsrv = { .s_addr = 0 };
 171 #endif
 172     NetClientState *nc;
 173     SlirpState *s;
 174     char buf[20];
 175     uint32_t addr;
 176     int shift;
 177     char *end;
 178     struct slirp_config_str *config;
 179
 180     if (!ipv4 && (vnetwork || vhost || vnameserver)) {
 181         error_setg(errp, "IPv4 disabled but netmask/host/dns provided");
 182         return -1;
 183     }
 184
 185     if (!ipv6 && (vprefix6 || vhost6 || vnameserver6)) {
 186         error_setg(errp, "IPv6 disabled but prefix/host6/dns6 provided");
 187         return -1;
 188     }
 189
 190     if (!ipv4 && !ipv6) {
 191         /* It doesn't make sense to disable both */
 192         error_setg(errp, "IPv4 and IPv6 disabled");
 193         return -1;
 194     }
 195
 196     if (!tftp_export) {
 197         tftp_export = legacy_tftp_prefix;
 198     }
 199     if (!bootfile) {
 200         bootfile = legacy_bootp_filename;
 201     }
 202
 203     if (vnetwork) {
 204         if (get_str_sep(buf, sizeof(buf), &vnetwork, '/') < 0) {
 205             if (!inet_aton(vnetwork, &net)) {
 206                 error_setg(errp, "Failed to parse netmask");
 207                 return -1;
 208             }
 209             addr = ntohl(net.s_addr);
 210             if (!(addr & 0x80000000)) {
 211                 mask.s_addr = htonl(0xff000000); /* class A */
 212             } else if ((addr & 0xfff00000) == 0xac100000) {
 213                 mask.s_addr = htonl(0xfff00000); /* priv. 172.16.0.0/12 */
 214             } else if ((addr & 0xc0000000) == 0x80000000) {
 215                 mask.s_addr = htonl(0xffff0000); /* class B */
 216             } else if ((addr & 0xffff0000) == 0xc0a80000) {
 217                 mask.s_addr = htonl(0xffff0000); /* priv. 192.168.0.0/16 */
 218             } else if ((addr & 0xffff0000) == 0xc6120000) {
 219                 mask.s_addr = htonl(0xfffe0000); /* tests 198.18.0.0/15 */
 220             } else if ((addr & 0xe0000000) == 0xe0000000) {
 221                 mask.s_addr = htonl(0xffffff00); /* class C */
 222             } else {
 223                 mask.s_addr = htonl(0xfffffff0); /* multicast/reserved */
 224             }
 225         } else {
 226             if (!inet_aton(buf, &net)) {
 227                 error_setg(errp, "Failed to parse netmask");
 228                 return -1;
 229             }
 230             shift = strtol(vnetwork, &end, 10);
 231             if (*end != '\0') {
 232                 if (!inet_aton(vnetwork, &mask)) {
 233                     error_setg(errp,
 234                                "Failed to parse netmask (trailing chars)");
 235                     return -1;
 236                 }
 237             } else if (shift < 4 || shift > 32) {
 238                 error_setg(errp,
 239                            "Invalid netmask provided (must be in range 4-32)");
 240                 return -1;
 241             } else {
 242                 mask.s_addr = htonl(0xffffffff << (32 - shift));
 243             }
 244         }
 245         net.s_addr &= mask.s_addr;
 246         host.s_addr = net.s_addr | (htonl(0x0202) & ~mask.s_addr);
 247         dhcp.s_addr = net.s_addr | (htonl(0x020f) & ~mask.s_addr);
 248         dns.s_addr  = net.s_addr | (htonl(0x0203) & ~mask.s_addr);
 249     }
 250
 251     if (vhost && !inet_aton(vhost, &host)) {
 252         error_setg(errp, "Failed to parse host");
 253         return -1;
 254     }
 255     if ((host.s_addr & mask.s_addr) != net.s_addr) {
 256         error_setg(errp, "Host doesn't belong to network");
 257         return -1;
 258     }
 259
 260     if (vnameserver && !inet_aton(vnameserver, &dns)) {
 261         error_setg(errp, "Failed to parse DNS");
 262         return -1;
 263     }
 264     if ((dns.s_addr & mask.s_addr) != net.s_addr) {
 265         error_setg(errp, "DNS doesn't belong to network");
 266         return -1;
 267     }
 268     if (dns.s_addr == host.s_addr) {
 269         error_setg(errp, "DNS must be different from host");
 270         return -1;
 271     }
 272
 273     if (vdhcp_start && !inet_aton(vdhcp_start, &dhcp)) {
 274         error_setg(errp, "Failed to parse DHCP start address");
 275         return -1;
 276     }
 277     if ((dhcp.s_addr & mask.s_addr) != net.s_addr) {
 278         error_setg(errp, "DHCP doesn't belong to network");
 279         return -1;
 280     }
 281     if (dhcp.s_addr == host.s_addr || dhcp.s_addr == dns.s_addr) {
 282         error_setg(errp, "DNS must be different from host and DNS");
 283         return -1;
 284     }
 285
 286 #ifndef _WIN32
 287     if (vsmbserver && !inet_aton(vsmbserver, &smbsrv)) {
 288         error_setg(errp, "Failed to parse SMB address");
 289         return -1;
 290     }
 291 #endif
 292
 293 #if defined(_WIN32) && (_WIN32_WINNT < 0x0600)
 294     /* No inet_pton helper before Vista... */
 295     if (vprefix6) {
 296         /* Unsupported */
 297         error_setg(errp, "IPv6 prefix not supported");
 298         return -1;
 299     }
 300     memset(&ip6_prefix, 0, sizeof(ip6_prefix));
 301     ip6_prefix.s6_addr[0] = 0xfe;
 302     ip6_prefix.s6_addr[1] = 0xc0;
 303 #else
 304     if (!vprefix6) {
 305         vprefix6 = "fec0::";
 306     }
 307     if (!inet_pton(AF_INET6, vprefix6, &ip6_prefix)) {
 308         error_setg(errp, "Failed to parse IPv6 prefix");
 309         return -1;
 310     }
 311 #endif
 312
 313     if (!vprefix6_len) {
 314         vprefix6_len = 64;
 315     }
 316     if (vprefix6_len < 0 || vprefix6_len > 126) {
 317         error_setg(errp,
 318                    "Invalid prefix provided (prefix len must be in range 0-126");
 319         return -1;
 320     }
 321
 322     if (vhost6) {
 323 #if defined(_WIN32) && (_WIN32_WINNT < 0x0600)
 324         error_setg(errp, "IPv6 host not supported");
 325         return -1;
 326 #else
 327         if (!inet_pton(AF_INET6, vhost6, &ip6_host)) {
 328             error_setg(errp, "Failed to parse IPv6 host");
 329             return -1;
 330         }
 331         if (!in6_equal_net(&ip6_prefix, &ip6_host, vprefix6_len)) {
 332             error_setg(errp, "IPv6 Host doesn't belong to network");
 333             return -1;
 334         }
 335 #endif
 336     } else {
 337         ip6_host = ip6_prefix;
 338         ip6_host.s6_addr[15] |= 2;
 339     }
 340
 341     if (vnameserver6) {
 342 #if defined(_WIN32) && (_WIN32_WINNT < 0x0600)
 343         error_setg(errp, "IPv6 DNS not supported");
 344         return -1;
 345 #else
 346         if (!inet_pton(AF_INET6, vnameserver6, &ip6_dns)) {
 347             error_setg(errp, "Failed to parse IPv6 DNS");
 348             return -1;
 349         }
 350         if (!in6_equal_net(&ip6_prefix, &ip6_dns, vprefix6_len)) {
 351             error_setg(errp, "IPv6 DNS doesn't belong to network");
 352             return -1;
 353         }
 354 #endif
 355     } else {
 356         ip6_dns = ip6_prefix;
 357         ip6_dns.s6_addr[15] |= 3;
 358     }
 359
 360
 361     nc = qemu_new_net_client(&net_slirp_info, peer, model, name);
 362
 363     snprintf(nc->info_str, sizeof(nc->info_str),
 364              "net=%s,restrict=%s", inet_ntoa(net),
 365              restricted ? "on" : "off");
 366
 367     s = DO_UPCAST(SlirpState, nc, nc);
 368
 369     s->slirp = slirp_init(restricted, ipv4, net, mask, host,
 370                           ipv6, ip6_prefix, vprefix6_len, ip6_host,
 371                           vhostname, tftp_export, bootfile, dhcp,
 372                           dns, ip6_dns, dnssearch, s);
 373     QTAILQ_INSERT_TAIL(&slirp_stacks, s, entry);
 374
 375     for (config = slirp_configs; config; config = config->next) {
 376         if (config->flags & SLIRP_CFG_HOSTFWD) {
 377             if (slirp_hostfwd(s, config->str,
 378                               config->flags & SLIRP_CFG_LEGACY, errp) < 0) {
 379                 goto error;
 380             }
 381         } else {
 382             if (slirp_guestfwd(s, config->str,
 383                                config->flags & SLIRP_CFG_LEGACY, errp) < 0) {
 384                 goto error;
 385             }
 386         }
 387     }
 388 #ifndef _WIN32
 389     if (!smb_export) {
 390         smb_export = legacy_smb_export;
 391     }
 392     if (smb_export) {
 393         if (slirp_smb(s, smb_export, smbsrv, errp) < 0) {
 394             goto error;
 395         }
 396     }
 397 #endif
 398
 399     s->exit_notifier.notify = slirp_smb_exit;
 400     qemu_add_exit_notifier(&s->exit_notifier);
 401     return 0;
 402
 403 error:
 404     qemu_del_net_client(nc);
 405     return -1;
 406 }
 407
 408 static SlirpState *slirp_lookup(Monitor *mon, const char *vlan,
 409                                 const char *stack)
 410 {
 411
 412     if (vlan) {
 413         NetClientState *nc;
 414         nc = net_hub_find_client_by_name(strtol(vlan, NULL, 0), stack);
 415         if (!nc) {
 416             monitor_printf(mon, "unrecognized (vlan-id, stackname) pair\n");
 417             return NULL;
 418         }
 419         if (strcmp(nc->model, "user")) {
 420             monitor_printf(mon, "invalid device specified\n");
 421             return NULL;
 422         }
 423         return DO_UPCAST(SlirpState, nc, nc);
 424     } else {
 425         if (QTAILQ_EMPTY(&slirp_stacks)) {
 426             monitor_printf(mon, "user mode network stack not in use\n");
 427             return NULL;
 428         }
 429         return QTAILQ_FIRST(&slirp_stacks);
 430     }
 431 }
 432
 433 void hmp_hostfwd_remove(Monitor *mon, const QDict *qdict)
 434 {
 435     struct in_addr host_addr = { .s_addr = INADDR_ANY };
 436     int host_port;
 437     char buf[256];
 438     const char *src_str, *p;
 439     SlirpState *s;
 440     int is_udp = 0;
 441     int err;
 442     const char *arg1 = qdict_get_str(qdict, "arg1");
 443     const char *arg2 = qdict_get_try_str(qdict, "arg2");
 444     const char *arg3 = qdict_get_try_str(qdict, "arg3");
 445
 446     if (arg2) {
 447         s = slirp_lookup(mon, arg1, arg2);
 448         src_str = arg3;
 449     } else {
 450         s = slirp_lookup(mon, NULL, NULL);
 451         src_str = arg1;
 452     }
 453     if (!s) {
 454         return;
 455     }
 456
 457     p = src_str;
 458     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 459         goto fail_syntax;
 460     }
 461
 462     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
 463         is_udp = 0;
 464     } else if (!strcmp(buf, "udp")) {
 465         is_udp = 1;
 466     } else {
 467         goto fail_syntax;
 468     }
 469
 470     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 471         goto fail_syntax;
 472     }
 473     if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
 474         goto fail_syntax;
 475     }
 476
 477     host_port = atoi(p);
 478
 479     err = slirp_remove_hostfwd(s->slirp, is_udp, host_addr, host_port);
 480
 481     monitor_printf(mon, "host forwarding rule for %s %s\n", src_str,
 482                    err ? "not found" : "removed");
 483     return;
 484
 485  fail_syntax:
 486     monitor_printf(mon, "invalid format\n");
 487 }
 488
 489 static int slirp_hostfwd(SlirpState *s, const char *redir_str,
 490                          int legacy_format, Error **errp)
 491 {
 492     struct in_addr host_addr = { .s_addr = INADDR_ANY };
 493     struct in_addr guest_addr = { .s_addr = 0 };
 494     int host_port, guest_port;
 495     const char *p;
 496     char buf[256];
 497     int is_udp;
 498     char *end;
 499
 500     p = redir_str;
 501     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 502         goto fail_syntax;
 503     }
 504     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
 505         is_udp = 0;
 506     } else if (!strcmp(buf, "udp")) {
 507         is_udp = 1;
 508     } else {
 509         goto fail_syntax;
 510     }
 511
 512     if (!legacy_format) {
 513         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 514             goto fail_syntax;
 515         }
 516         if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
 517             goto fail_syntax;
 518         }
 519     }
 520
 521     if (get_str_sep(buf, sizeof(buf), &p, legacy_format ? ':' : '-') < 0) {
 522         goto fail_syntax;
 523     }
 524     host_port = strtol(buf, &end, 0);
 525     if (*end != '\0' || host_port < 0 || host_port > 65535) {
 526         goto fail_syntax;
 527     }
 528
 529     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 530         goto fail_syntax;
 531     }
 532     if (buf[0] != '\0' && !inet_aton(buf, &guest_addr)) {
 533         goto fail_syntax;
 534     }
 535
 536     guest_port = strtol(p, &end, 0);
 537     if (*end != '\0' || guest_port < 1 || guest_port > 65535) {
 538         goto fail_syntax;
 539     }
 540
 541     if (slirp_add_hostfwd(s->slirp, is_udp, host_addr, host_port, guest_addr,
 542                           guest_port) < 0) {
 543         error_setg(errp, "Could not set up host forwarding rule '%s'",
 544                    redir_str);
 545         return -1;
 546     }
 547     return 0;
 548
 549  fail_syntax:
 550     error_setg(errp, "Invalid host forwarding rule '%s'", redir_str);
 551     return -1;
 552 }
 553
 554 void hmp_hostfwd_add(Monitor *mon, const QDict *qdict)
 555 {
 556     const char *redir_str;
 557     SlirpState *s;
 558     const char *arg1 = qdict_get_str(qdict, "arg1");
 559     const char *arg2 = qdict_get_try_str(qdict, "arg2");
 560     const char *arg3 = qdict_get_try_str(qdict, "arg3");
 561
 562     if (arg2) {
 563         s = slirp_lookup(mon, arg1, arg2);
 564         redir_str = arg3;
 565     } else {
 566         s = slirp_lookup(mon, NULL, NULL);
 567         redir_str = arg1;
 568     }
 569     if (s) {
 570         Error *err = NULL;
 571         if (slirp_hostfwd(s, redir_str, 0, &err) < 0) {
 572             error_report_err(err);
 573         }
 574     }
 575
 576 }
 577
 578 int net_slirp_redir(const char *redir_str)
 579 {
 580     struct slirp_config_str *config;
 581     Error *err = NULL;
 582     int res;
 583
 584     if (QTAILQ_EMPTY(&slirp_stacks)) {
 585         config = g_malloc(sizeof(*config));
 586         pstrcpy(config->str, sizeof(config->str), redir_str);
 587         config->flags = SLIRP_CFG_HOSTFWD | SLIRP_CFG_LEGACY;
 588         config->next = slirp_configs;
 589         slirp_configs = config;
 590         return 0;
 591     }
 592
 593     res = slirp_hostfwd(QTAILQ_FIRST(&slirp_stacks), redir_str, 1, &err);
 594     if (res < 0) {
 595         error_report_err(err);
 596     }
 597     return res;
 598 }
 599
 600 #ifndef _WIN32
 601
 602 /* automatic user mode samba server configuration */
 603 static void slirp_smb_cleanup(SlirpState *s)
 604 {
 605     int ret;
 606
 607     if (s->smb_dir) {
 608         gchar *cmd = g_strdup_printf("rm -rf %s", s->smb_dir);
 609         ret = system(cmd);
 610         if (ret == -1 || !WIFEXITED(ret)) {
 611             error_report("'%s' failed.", cmd);
 612         } else if (WEXITSTATUS(ret)) {
 613             error_report("'%s' failed. Error code: %d",
 614                          cmd, WEXITSTATUS(ret));
 615         }
 616         g_free(cmd);
 617         g_free(s->smb_dir);
 618         s->smb_dir = NULL;
 619     }
 620 }
 621
 622 static int slirp_smb(SlirpState* s, const char *exported_dir,
 623                      struct in_addr vserver_addr, Error **errp)
 624 {
 625     char *smb_conf;
 626     char *smb_cmdline;
 627     struct passwd *passwd;
 628     FILE *f;
 629
 630     passwd = getpwuid(geteuid());
 631     if (!passwd) {
 632         error_setg(errp, "Failed to retrieve user name");
 633         return -1;
 634     }
 635
 636     if (access(CONFIG_SMBD_COMMAND, F_OK)) {
 637         error_setg(errp, "Could not find '%s', please install it",
 638                    CONFIG_SMBD_COMMAND);
 639         return -1;
 640     }
 641
 642     if (access(exported_dir, R_OK | X_OK)) {
 643         error_setg(errp, "Error accessing shared directory '%s': %s",
 644                    exported_dir, strerror(errno));
 645         return -1;
 646     }
 647
 648     s->smb_dir = g_dir_make_tmp("qemu-smb.XXXXXX", NULL);
 649     if (!s->smb_dir) {
 650         error_setg(errp, "Could not create samba server dir");
 651         return -1;
 652     }
 653     smb_conf = g_strdup_printf("%s/%s", s->smb_dir, "smb.conf");
 654
 655     f = fopen(smb_conf, "w");
 656     if (!f) {
 657         slirp_smb_cleanup(s);
 658         error_setg(errp,
 659                    "Could not create samba server configuration file '%s'",
 660                     smb_conf);
 661         g_free(smb_conf);
 662         return -1;
 663     }
 664     fprintf(f,
 665             "[global]\n"
 666             "private dir=%s\n"
 667             "interfaces=127.0.0.1\n"
 668             "bind interfaces only=yes\n"
 669             "pid directory=%s\n"
 670             "lock directory=%s\n"
 671             "state directory=%s\n"
 672             "cache directory=%s\n"
 673             "ncalrpc dir=%s/ncalrpc\n"
 674             "log file=%s/log.smbd\n"
 675             "smb passwd file=%s/smbpasswd\n"
 676             "security = user\n"
 677             "map to guest = Bad User\n"
 678             "load printers = no\n"
 679             "printing = bsd\n"
 680             "disable spoolss = yes\n"
 681             "usershare max shares = 0\n"
 682             "[qemu]\n"
 683             "path=%s\n"
 684             "read only=no\n"
 685             "guest ok=yes\n"
 686             "force user=%s\n",
 687             s->smb_dir,
 688             s->smb_dir,
 689             s->smb_dir,
 690             s->smb_dir,
 691             s->smb_dir,
 692             s->smb_dir,
 693             s->smb_dir,
 694             s->smb_dir,
 695             exported_dir,
 696             passwd->pw_name
 697             );
 698     fclose(f);
 699
 700     smb_cmdline = g_strdup_printf("%s -l %s -s %s",
 701              CONFIG_SMBD_COMMAND, s->smb_dir, smb_conf);
 702     g_free(smb_conf);
 703
 704     if (slirp_add_exec(s->slirp, 0, smb_cmdline, &vserver_addr, 139) < 0 ||
 705         slirp_add_exec(s->slirp, 0, smb_cmdline, &vserver_addr, 445) < 0) {
 706         slirp_smb_cleanup(s);
 707         g_free(smb_cmdline);
 708         error_setg(errp, "Conflicting/invalid smbserver address");
 709         return -1;
 710     }
 711     g_free(smb_cmdline);
 712     return 0;
 713 }
 714
 715 /* automatic user mode samba server configuration (legacy interface) */
 716 int net_slirp_smb(const char *exported_dir)
 717 {
 718     struct in_addr vserver_addr = { .s_addr = 0 };
 719
 720     if (legacy_smb_export) {
 721         fprintf(stderr, "-smb given twice\n");
 722         return -1;
 723     }
 724     legacy_smb_export = exported_dir;
 725     if (!QTAILQ_EMPTY(&slirp_stacks)) {
 726         Error *err = NULL;
 727         int res = slirp_smb(QTAILQ_FIRST(&slirp_stacks), exported_dir,
 728                             vserver_addr, &err);
 729         if (res < 0) {
 730             error_report_err(err);
 731         }
 732         return res;
 733     }
 734     return 0;
 735 }
 736
 737 #endif /* !defined(_WIN32) */
 738
 739 struct GuestFwd {
 740     CharBackend hd;
 741     struct in_addr server;
 742     int port;
 743     Slirp *slirp;
 744 };
 745
 746 static int guestfwd_can_read(void *opaque)
 747 {
 748     struct GuestFwd *fwd = opaque;
 749     return slirp_socket_can_recv(fwd->slirp, fwd->server, fwd->port);
 750 }
 751
 752 static void guestfwd_read(void *opaque, const uint8_t *buf, int size)
 753 {
 754     struct GuestFwd *fwd = opaque;
 755     slirp_socket_recv(fwd->slirp, fwd->server, fwd->port, buf, size);
 756 }
 757
 758 static int slirp_guestfwd(SlirpState *s, const char *config_str,
 759                           int legacy_format, Error **errp)
 760 {
 761     struct in_addr server = { .s_addr = 0 };
 762     struct GuestFwd *fwd;
 763     const char *p;
 764     char buf[128];
 765     char *end;
 766     int port;
 767
 768     p = config_str;
 769     if (legacy_format) {
 770         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 771             goto fail_syntax;
 772         }
 773     } else {
 774         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 775             goto fail_syntax;
 776         }
 777         if (strcmp(buf, "tcp") && buf[0] != '\0') {
 778             goto fail_syntax;
 779         }
 780         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 781             goto fail_syntax;
 782         }
 783         if (buf[0] != '\0' && !inet_aton(buf, &server)) {
 784             goto fail_syntax;
 785         }
 786         if (get_str_sep(buf, sizeof(buf), &p, '-') < 0) {
 787             goto fail_syntax;
 788         }
 789     }
 790     port = strtol(buf, &end, 10);
 791     if (*end != '\0' || port < 1 || port > 65535) {
 792         goto fail_syntax;
 793     }
 794
 795     snprintf(buf, sizeof(buf), "guestfwd.tcp.%d", port);
 796
 797     if ((strlen(p) > 4) && !strncmp(p, "cmd:", 4)) {
 798         if (slirp_add_exec(s->slirp, 0, &p[4], &server, port) < 0) {
 799             error_setg(errp, "Conflicting/invalid host:port in guest "
 800                        "forwarding rule '%s'", config_str);
 801             return -1;
 802         }
 803     } else {
 804         Error *err = NULL;
 805         Chardev *chr = qemu_chr_new(buf, p);
 806
 807         if (!chr) {
 808             error_setg(errp, "Could not open guest forwarding device '%s'",
 809                        buf);
 810             return -1;
 811         }
 812
 813         fwd = g_new(struct GuestFwd, 1);
 814         qemu_chr_fe_init(&fwd->hd, chr, &err);
 815         if (err) {
 816             error_propagate(errp, err);
 817             g_free(fwd);
 818             return -1;
 819         }
 820
 821         if (slirp_add_exec(s->slirp, 3, &fwd->hd, &server, port) < 0) {
 822             error_setg(errp, "Conflicting/invalid host:port in guest "
 823                        "forwarding rule '%s'", config_str);
 824             g_free(fwd);
 825             return -1;
 826         }
 827         fwd->server = server;
 828         fwd->port = port;
 829         fwd->slirp = s->slirp;
 830
 831         qemu_chr_fe_set_handlers(&fwd->hd, guestfwd_can_read, guestfwd_read,
 832                                  NULL, NULL, fwd, NULL, true);
 833     }
 834     return 0;
 835
 836  fail_syntax:
 837     error_setg(errp, "Invalid guest forwarding rule '%s'", config_str);
 838     return -1;
 839 }
 840
 841 void hmp_info_usernet(Monitor *mon, const QDict *qdict)
 842 {
 843     SlirpState *s;
 844
 845     QTAILQ_FOREACH(s, &slirp_stacks, entry) {
 846         int id;
 847         bool got_vlan_id = net_hub_id_for_client(&s->nc, &id) == 0;
 848         monitor_printf(mon, "VLAN %d (%s):\n",
 849                        got_vlan_id ? id : -1,
 850                        s->nc.name);
 851         slirp_connection_info(s->slirp, mon);
 852     }
 853 }
 854
 855 static void
 856 net_init_slirp_configs(const StringList *fwd, int flags)
 857 {
 858     while (fwd) {
 859         struct slirp_config_str *config;
 860
 861         config = g_malloc0(sizeof(*config));
 862         pstrcpy(config->str, sizeof(config->str), fwd->value->str);
 863         config->flags = flags;
 864         config->next = slirp_configs;
 865         slirp_configs = config;
 866
 867         fwd = fwd->next;
 868     }
 869 }
 870
 871 static const char **slirp_dnssearch(const StringList *dnsname)
 872 {
 873     const StringList *c = dnsname;
 874     size_t i = 0, num_opts = 0;
 875     const char **ret;
 876
 877     while (c) {
 878         num_opts++;
 879         c = c->next;
 880     }
 881
 882     if (num_opts == 0) {
 883         return NULL;
 884     }
 885
 886     ret = g_malloc((num_opts + 1) * sizeof(*ret));
 887     c = dnsname;
 888     while (c) {
 889         ret[i++] = c->value->str;
 890         c = c->next;
 891     }
 892     ret[i] = NULL;
 893     return ret;
 894 }
 895
 896 int net_init_slirp(const Netdev *netdev, const char *name,
 897                    NetClientState *peer, Error **errp)
 898 {
 899     struct slirp_config_str *config;
 900     char *vnet;
 901     int ret;
 902     const NetdevUserOptions *user;
 903     const char **dnssearch;
 904     bool ipv4 = true, ipv6 = true;
 905
 906     assert(netdev->type == NET_CLIENT_DRIVER_USER);
 907     user = &netdev->u.user;
 908
 909     if ((user->has_ipv6 && user->ipv6 && !user->has_ipv4) ||
 910         (user->has_ipv4 && !user->ipv4)) {
 911         ipv4 = 0;
 912     }
 913     if ((user->has_ipv4 && user->ipv4 && !user->has_ipv6) ||
 914         (user->has_ipv6 && !user->ipv6)) {
 915         ipv6 = 0;
 916     }
 917
 918     vnet = user->has_net ? g_strdup(user->net) :
 919            user->has_ip  ? g_strdup_printf("%s/24", user->ip) :
 920            NULL;
 921
 922     dnssearch = slirp_dnssearch(user->dnssearch);
 923
 924     /* all optional fields are initialized to "all bits zero" */
 925
 926     net_init_slirp_configs(user->hostfwd, SLIRP_CFG_HOSTFWD);
 927     net_init_slirp_configs(user->guestfwd, 0);
 928
 929     ret = net_slirp_init(peer, "user", name, user->q_restrict,
 930                          ipv4, vnet, user->host,
 931                          ipv6, user->ipv6_prefix, user->ipv6_prefixlen,
 932                          user->ipv6_host, user->hostname, user->tftp,
 933                          user->bootfile, user->dhcpstart,
 934                          user->dns, user->ipv6_dns, user->smb,
 935                          user->smbserver, dnssearch, errp);
 936
 937     while (slirp_configs) {
 938         config = slirp_configs;
 939         slirp_configs = config->next;
 940         g_free(config);
 941     }
 942
 943     g_free(vnet);
 944     g_free(dnssearch);
 945
 946     return ret;
 947 }
 948
 949 int net_slirp_parse_legacy(QemuOptsList *opts_list, const char *optarg, int *ret)
 950 {
 951     if (strcmp(opts_list->name, "net") != 0 ||
 952         strncmp(optarg, "channel,", strlen("channel,")) != 0) {
 953         return 0;
 954     }
 955
 956     error_report("The '-net channel' option is deprecated. "
 957                  "Please use '-netdev user,guestfwd=...' instead.");
 958
 959     /* handle legacy -net channel,port:chr */
 960     optarg += strlen("channel,");
 961
 962     if (QTAILQ_EMPTY(&slirp_stacks)) {
 963         struct slirp_config_str *config;
 964
 965         config = g_malloc(sizeof(*config));
 966         pstrcpy(config->str, sizeof(config->str), optarg);
 967         config->flags = SLIRP_CFG_LEGACY;
 968         config->next = slirp_configs;
 969         slirp_configs = config;
 970         *ret = 0;
 971     } else {
 972         Error *err = NULL;
 973         *ret = slirp_guestfwd(QTAILQ_FIRST(&slirp_stacks), optarg, 1, &err);
 974         if (*ret < 0) {
 975             error_report_err(err);
 976         }
 977     }
 978
 979     return 1;
 980 }
 981