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