xref: /openbmc/qemu/net/slirp.c (revision 0ed93f4c)
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_del(timer);
188     timer_free(timer);
189 }
190 
191 static void net_slirp_timer_mod(void *timer, int64_t expire_timer,
192                                 void *opaque)
193 {
194     timer_mod(timer, expire_timer);
195 }
196 
197 static void net_slirp_register_poll_fd(int fd, void *opaque)
198 {
199     qemu_fd_register(fd);
200 }
201 
202 static void net_slirp_unregister_poll_fd(int fd, void *opaque)
203 {
204     /* no qemu_fd_unregister */
205 }
206 
207 static void net_slirp_notify(void *opaque)
208 {
209     qemu_notify_event();
210 }
211 
212 static const SlirpCb slirp_cb = {
213     .send_packet = net_slirp_send_packet,
214     .guest_error = net_slirp_guest_error,
215     .clock_get_ns = net_slirp_clock_get_ns,
216     .timer_new = net_slirp_timer_new,
217     .timer_free = net_slirp_timer_free,
218     .timer_mod = net_slirp_timer_mod,
219     .register_poll_fd = net_slirp_register_poll_fd,
220     .unregister_poll_fd = net_slirp_unregister_poll_fd,
221     .notify = net_slirp_notify,
222 };
223 
224 static int slirp_poll_to_gio(int events)
225 {
226     int ret = 0;
227 
228     if (events & SLIRP_POLL_IN) {
229         ret |= G_IO_IN;
230     }
231     if (events & SLIRP_POLL_OUT) {
232         ret |= G_IO_OUT;
233     }
234     if (events & SLIRP_POLL_PRI) {
235         ret |= G_IO_PRI;
236     }
237     if (events & SLIRP_POLL_ERR) {
238         ret |= G_IO_ERR;
239     }
240     if (events & SLIRP_POLL_HUP) {
241         ret |= G_IO_HUP;
242     }
243 
244     return ret;
245 }
246 
247 static int net_slirp_add_poll(int fd, int events, void *opaque)
248 {
249     GArray *pollfds = opaque;
250     GPollFD pfd = {
251         .fd = fd,
252         .events = slirp_poll_to_gio(events),
253     };
254     int idx = pollfds->len;
255     g_array_append_val(pollfds, pfd);
256     return idx;
257 }
258 
259 static int slirp_gio_to_poll(int events)
260 {
261     int ret = 0;
262 
263     if (events & G_IO_IN) {
264         ret |= SLIRP_POLL_IN;
265     }
266     if (events & G_IO_OUT) {
267         ret |= SLIRP_POLL_OUT;
268     }
269     if (events & G_IO_PRI) {
270         ret |= SLIRP_POLL_PRI;
271     }
272     if (events & G_IO_ERR) {
273         ret |= SLIRP_POLL_ERR;
274     }
275     if (events & G_IO_HUP) {
276         ret |= SLIRP_POLL_HUP;
277     }
278 
279     return ret;
280 }
281 
282 static int net_slirp_get_revents(int idx, void *opaque)
283 {
284     GArray *pollfds = opaque;
285 
286     return slirp_gio_to_poll(g_array_index(pollfds, GPollFD, idx).revents);
287 }
288 
289 static void net_slirp_poll_notify(Notifier *notifier, void *data)
290 {
291     MainLoopPoll *poll = data;
292     SlirpState *s = container_of(notifier, SlirpState, poll_notifier);
293 
294     switch (poll->state) {
295     case MAIN_LOOP_POLL_FILL:
296         slirp_pollfds_fill(s->slirp, &poll->timeout,
297                            net_slirp_add_poll, poll->pollfds);
298         break;
299     case MAIN_LOOP_POLL_OK:
300     case MAIN_LOOP_POLL_ERR:
301         slirp_pollfds_poll(s->slirp, poll->state == MAIN_LOOP_POLL_ERR,
302                            net_slirp_get_revents, poll->pollfds);
303         break;
304     default:
305         g_assert_not_reached();
306     }
307 }
308 
309 static ssize_t
310 net_slirp_stream_read(void *buf, size_t size, void *opaque)
311 {
312     QEMUFile *f = opaque;
313 
314     return qemu_get_buffer(f, buf, size);
315 }
316 
317 static ssize_t
318 net_slirp_stream_write(const void *buf, size_t size, void *opaque)
319 {
320     QEMUFile *f = opaque;
321 
322     qemu_put_buffer(f, buf, size);
323     if (qemu_file_get_error(f)) {
324         return -1;
325     }
326 
327     return size;
328 }
329 
330 static int net_slirp_state_load(QEMUFile *f, void *opaque, int version_id)
331 {
332     Slirp *slirp = opaque;
333 
334     return slirp_state_load(slirp, version_id, net_slirp_stream_read, f);
335 }
336 
337 static void net_slirp_state_save(QEMUFile *f, void *opaque)
338 {
339     Slirp *slirp = opaque;
340 
341     slirp_state_save(slirp, net_slirp_stream_write, f);
342 }
343 
344 static SaveVMHandlers savevm_slirp_state = {
345     .save_state = net_slirp_state_save,
346     .load_state = net_slirp_state_load,
347 };
348 
349 static int net_slirp_init(NetClientState *peer, const char *model,
350                           const char *name, int restricted,
351                           bool ipv4, const char *vnetwork, const char *vhost,
352                           bool ipv6, const char *vprefix6, int vprefix6_len,
353                           const char *vhost6,
354                           const char *vhostname, const char *tftp_export,
355                           const char *bootfile, const char *vdhcp_start,
356                           const char *vnameserver, const char *vnameserver6,
357                           const char *smb_export, const char *vsmbserver,
358                           const char **dnssearch, const char *vdomainname,
359                           const char *tftp_server_name,
360                           Error **errp)
361 {
362     /* default settings according to historic slirp */
363     struct in_addr net  = { .s_addr = htonl(0x0a000200) }; /* 10.0.2.0 */
364     struct in_addr mask = { .s_addr = htonl(0xffffff00) }; /* 255.255.255.0 */
365     struct in_addr host = { .s_addr = htonl(0x0a000202) }; /* 10.0.2.2 */
366     struct in_addr dhcp = { .s_addr = htonl(0x0a00020f) }; /* 10.0.2.15 */
367     struct in_addr dns  = { .s_addr = htonl(0x0a000203) }; /* 10.0.2.3 */
368     struct in6_addr ip6_prefix;
369     struct in6_addr ip6_host;
370     struct in6_addr ip6_dns;
371 #ifndef _WIN32
372     struct in_addr smbsrv = { .s_addr = 0 };
373 #endif
374     NetClientState *nc;
375     SlirpState *s;
376     char buf[20];
377     uint32_t addr;
378     int shift;
379     char *end;
380     struct slirp_config_str *config;
381 
382     if (!ipv4 && (vnetwork || vhost || vnameserver)) {
383         error_setg(errp, "IPv4 disabled but netmask/host/dns provided");
384         return -1;
385     }
386 
387     if (!ipv6 && (vprefix6 || vhost6 || vnameserver6)) {
388         error_setg(errp, "IPv6 disabled but prefix/host6/dns6 provided");
389         return -1;
390     }
391 
392     if (!ipv4 && !ipv6) {
393         /* It doesn't make sense to disable both */
394         error_setg(errp, "IPv4 and IPv6 disabled");
395         return -1;
396     }
397 
398     if (vnetwork) {
399         if (get_str_sep(buf, sizeof(buf), &vnetwork, '/') < 0) {
400             if (!inet_aton(vnetwork, &net)) {
401                 error_setg(errp, "Failed to parse netmask");
402                 return -1;
403             }
404             addr = ntohl(net.s_addr);
405             if (!(addr & 0x80000000)) {
406                 mask.s_addr = htonl(0xff000000); /* class A */
407             } else if ((addr & 0xfff00000) == 0xac100000) {
408                 mask.s_addr = htonl(0xfff00000); /* priv. 172.16.0.0/12 */
409             } else if ((addr & 0xc0000000) == 0x80000000) {
410                 mask.s_addr = htonl(0xffff0000); /* class B */
411             } else if ((addr & 0xffff0000) == 0xc0a80000) {
412                 mask.s_addr = htonl(0xffff0000); /* priv. 192.168.0.0/16 */
413             } else if ((addr & 0xffff0000) == 0xc6120000) {
414                 mask.s_addr = htonl(0xfffe0000); /* tests 198.18.0.0/15 */
415             } else if ((addr & 0xe0000000) == 0xe0000000) {
416                 mask.s_addr = htonl(0xffffff00); /* class C */
417             } else {
418                 mask.s_addr = htonl(0xfffffff0); /* multicast/reserved */
419             }
420         } else {
421             if (!inet_aton(buf, &net)) {
422                 error_setg(errp, "Failed to parse netmask");
423                 return -1;
424             }
425             shift = strtol(vnetwork, &end, 10);
426             if (*end != '\0') {
427                 if (!inet_aton(vnetwork, &mask)) {
428                     error_setg(errp,
429                                "Failed to parse netmask (trailing chars)");
430                     return -1;
431                 }
432             } else if (shift < 4 || shift > 32) {
433                 error_setg(errp,
434                            "Invalid netmask provided (must be in range 4-32)");
435                 return -1;
436             } else {
437                 mask.s_addr = htonl(0xffffffff << (32 - shift));
438             }
439         }
440         net.s_addr &= mask.s_addr;
441         host.s_addr = net.s_addr | (htonl(0x0202) & ~mask.s_addr);
442         dhcp.s_addr = net.s_addr | (htonl(0x020f) & ~mask.s_addr);
443         dns.s_addr  = net.s_addr | (htonl(0x0203) & ~mask.s_addr);
444     }
445 
446     if (vhost && !inet_aton(vhost, &host)) {
447         error_setg(errp, "Failed to parse host");
448         return -1;
449     }
450     if ((host.s_addr & mask.s_addr) != net.s_addr) {
451         error_setg(errp, "Host doesn't belong to network");
452         return -1;
453     }
454 
455     if (vnameserver && !inet_aton(vnameserver, &dns)) {
456         error_setg(errp, "Failed to parse DNS");
457         return -1;
458     }
459     if (restricted && (dns.s_addr & mask.s_addr) != net.s_addr) {
460         error_setg(errp, "DNS doesn't belong to network");
461         return -1;
462     }
463     if (dns.s_addr == host.s_addr) {
464         error_setg(errp, "DNS must be different from host");
465         return -1;
466     }
467 
468     if (vdhcp_start && !inet_aton(vdhcp_start, &dhcp)) {
469         error_setg(errp, "Failed to parse DHCP start address");
470         return -1;
471     }
472     if ((dhcp.s_addr & mask.s_addr) != net.s_addr) {
473         error_setg(errp, "DHCP doesn't belong to network");
474         return -1;
475     }
476     if (dhcp.s_addr == host.s_addr || dhcp.s_addr == dns.s_addr) {
477         error_setg(errp, "DNS must be different from host and DNS");
478         return -1;
479     }
480 
481 #ifndef _WIN32
482     if (vsmbserver && !inet_aton(vsmbserver, &smbsrv)) {
483         error_setg(errp, "Failed to parse SMB address");
484         return -1;
485     }
486 #endif
487 
488     if (!vprefix6) {
489         vprefix6 = "fec0::";
490     }
491     if (!inet_pton(AF_INET6, vprefix6, &ip6_prefix)) {
492         error_setg(errp, "Failed to parse IPv6 prefix");
493         return -1;
494     }
495 
496     if (!vprefix6_len) {
497         vprefix6_len = 64;
498     }
499     if (vprefix6_len < 0 || vprefix6_len > 126) {
500         error_setg(errp,
501                    "Invalid IPv6 prefix provided "
502                    "(IPv6 prefix length must be between 0 and 126)");
503         return -1;
504     }
505 
506     if (vhost6) {
507         if (!inet_pton(AF_INET6, vhost6, &ip6_host)) {
508             error_setg(errp, "Failed to parse IPv6 host");
509             return -1;
510         }
511         if (!in6_equal_net(&ip6_prefix, &ip6_host, vprefix6_len)) {
512             error_setg(errp, "IPv6 Host doesn't belong to network");
513             return -1;
514         }
515     } else {
516         ip6_host = ip6_prefix;
517         ip6_host.s6_addr[15] |= 2;
518     }
519 
520     if (vnameserver6) {
521         if (!inet_pton(AF_INET6, vnameserver6, &ip6_dns)) {
522             error_setg(errp, "Failed to parse IPv6 DNS");
523             return -1;
524         }
525         if (restricted && !in6_equal_net(&ip6_prefix, &ip6_dns, vprefix6_len)) {
526             error_setg(errp, "IPv6 DNS doesn't belong to network");
527             return -1;
528         }
529     } else {
530         ip6_dns = ip6_prefix;
531         ip6_dns.s6_addr[15] |= 3;
532     }
533 
534     if (vdomainname && !*vdomainname) {
535         error_setg(errp, "'domainname' parameter cannot be empty");
536         return -1;
537     }
538 
539     if (vdomainname && strlen(vdomainname) > 255) {
540         error_setg(errp, "'domainname' parameter cannot exceed 255 bytes");
541         return -1;
542     }
543 
544     if (vhostname && strlen(vhostname) > 255) {
545         error_setg(errp, "'vhostname' parameter cannot exceed 255 bytes");
546         return -1;
547     }
548 
549     if (tftp_server_name && strlen(tftp_server_name) > 255) {
550         error_setg(errp, "'tftp-server-name' parameter cannot exceed 255 bytes");
551         return -1;
552     }
553 
554     nc = qemu_new_net_client(&net_slirp_info, peer, model, name);
555 
556     snprintf(nc->info_str, sizeof(nc->info_str),
557              "net=%s,restrict=%s", inet_ntoa(net),
558              restricted ? "on" : "off");
559 
560     s = DO_UPCAST(SlirpState, nc, nc);
561 
562     s->slirp = slirp_init(restricted, ipv4, net, mask, host,
563                           ipv6, ip6_prefix, vprefix6_len, ip6_host,
564                           vhostname, tftp_server_name,
565                           tftp_export, bootfile, dhcp,
566                           dns, ip6_dns, dnssearch, vdomainname,
567                           &slirp_cb, s);
568     QTAILQ_INSERT_TAIL(&slirp_stacks, s, entry);
569 
570     /*
571      * Make sure the current bitstream version of slirp is 4, to avoid
572      * QEMU migration incompatibilities, if upstream slirp bumped the
573      * version.
574      *
575      * FIXME: use bitfields of features? teach libslirp to save with
576      * specific version?
577      */
578     g_assert(slirp_state_version() == 4);
579     register_savevm_live("slirp", 0, slirp_state_version(),
580                          &savevm_slirp_state, s->slirp);
581 
582     s->poll_notifier.notify = net_slirp_poll_notify;
583     main_loop_poll_add_notifier(&s->poll_notifier);
584 
585     for (config = slirp_configs; config; config = config->next) {
586         if (config->flags & SLIRP_CFG_HOSTFWD) {
587             if (slirp_hostfwd(s, config->str, errp) < 0) {
588                 goto error;
589             }
590         } else {
591             if (slirp_guestfwd(s, config->str, errp) < 0) {
592                 goto error;
593             }
594         }
595     }
596 #ifndef _WIN32
597     if (smb_export) {
598         if (slirp_smb(s, smb_export, smbsrv, errp) < 0) {
599             goto error;
600         }
601     }
602 #endif
603 
604     s->exit_notifier.notify = slirp_smb_exit;
605     qemu_add_exit_notifier(&s->exit_notifier);
606     return 0;
607 
608 error:
609     qemu_del_net_client(nc);
610     return -1;
611 }
612 
613 static SlirpState *slirp_lookup(Monitor *mon, const char *id)
614 {
615     if (id) {
616         NetClientState *nc = qemu_find_netdev(id);
617         if (!nc) {
618             monitor_printf(mon, "unrecognized netdev id '%s'\n", id);
619             return NULL;
620         }
621         if (strcmp(nc->model, "user")) {
622             monitor_printf(mon, "invalid device specified\n");
623             return NULL;
624         }
625         return DO_UPCAST(SlirpState, nc, nc);
626     } else {
627         if (QTAILQ_EMPTY(&slirp_stacks)) {
628             monitor_printf(mon, "user mode network stack not in use\n");
629             return NULL;
630         }
631         return QTAILQ_FIRST(&slirp_stacks);
632     }
633 }
634 
635 void hmp_hostfwd_remove(Monitor *mon, const QDict *qdict)
636 {
637     struct in_addr host_addr = { .s_addr = INADDR_ANY };
638     int host_port;
639     char buf[256];
640     const char *src_str, *p;
641     SlirpState *s;
642     int is_udp = 0;
643     int err;
644     const char *arg1 = qdict_get_str(qdict, "arg1");
645     const char *arg2 = qdict_get_try_str(qdict, "arg2");
646 
647     if (arg2) {
648         s = slirp_lookup(mon, arg1);
649         src_str = arg2;
650     } else {
651         s = slirp_lookup(mon, NULL);
652         src_str = arg1;
653     }
654     if (!s) {
655         return;
656     }
657 
658     p = src_str;
659     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
660         goto fail_syntax;
661     }
662 
663     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
664         is_udp = 0;
665     } else if (!strcmp(buf, "udp")) {
666         is_udp = 1;
667     } else {
668         goto fail_syntax;
669     }
670 
671     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
672         goto fail_syntax;
673     }
674     if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
675         goto fail_syntax;
676     }
677 
678     if (qemu_strtoi(p, NULL, 10, &host_port)) {
679         goto fail_syntax;
680     }
681 
682     err = slirp_remove_hostfwd(s->slirp, is_udp, host_addr, host_port);
683 
684     monitor_printf(mon, "host forwarding rule for %s %s\n", src_str,
685                    err ? "not found" : "removed");
686     return;
687 
688  fail_syntax:
689     monitor_printf(mon, "invalid format\n");
690 }
691 
692 static int slirp_hostfwd(SlirpState *s, const char *redir_str, Error **errp)
693 {
694     struct in_addr host_addr = { .s_addr = INADDR_ANY };
695     struct in_addr guest_addr = { .s_addr = 0 };
696     int host_port, guest_port;
697     const char *p;
698     char buf[256];
699     int is_udp;
700     char *end;
701     const char *fail_reason = "Unknown reason";
702 
703     p = redir_str;
704     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
705         fail_reason = "No : separators";
706         goto fail_syntax;
707     }
708     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
709         is_udp = 0;
710     } else if (!strcmp(buf, "udp")) {
711         is_udp = 1;
712     } else {
713         fail_reason = "Bad protocol name";
714         goto fail_syntax;
715     }
716 
717     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
718         fail_reason = "Missing : separator";
719         goto fail_syntax;
720     }
721     if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
722         fail_reason = "Bad host address";
723         goto fail_syntax;
724     }
725 
726     if (get_str_sep(buf, sizeof(buf), &p, '-') < 0) {
727         fail_reason = "Bad host port separator";
728         goto fail_syntax;
729     }
730     host_port = strtol(buf, &end, 0);
731     if (*end != '\0' || host_port < 0 || host_port > 65535) {
732         fail_reason = "Bad host port";
733         goto fail_syntax;
734     }
735 
736     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
737         fail_reason = "Missing guest address";
738         goto fail_syntax;
739     }
740     if (buf[0] != '\0' && !inet_aton(buf, &guest_addr)) {
741         fail_reason = "Bad guest address";
742         goto fail_syntax;
743     }
744 
745     guest_port = strtol(p, &end, 0);
746     if (*end != '\0' || guest_port < 1 || guest_port > 65535) {
747         fail_reason = "Bad guest port";
748         goto fail_syntax;
749     }
750 
751     if (slirp_add_hostfwd(s->slirp, is_udp, host_addr, host_port, guest_addr,
752                           guest_port) < 0) {
753         error_setg(errp, "Could not set up host forwarding rule '%s'",
754                    redir_str);
755         return -1;
756     }
757     return 0;
758 
759  fail_syntax:
760     error_setg(errp, "Invalid host forwarding rule '%s' (%s)", redir_str,
761                fail_reason);
762     return -1;
763 }
764 
765 void hmp_hostfwd_add(Monitor *mon, const QDict *qdict)
766 {
767     const char *redir_str;
768     SlirpState *s;
769     const char *arg1 = qdict_get_str(qdict, "arg1");
770     const char *arg2 = qdict_get_try_str(qdict, "arg2");
771 
772     if (arg2) {
773         s = slirp_lookup(mon, arg1);
774         redir_str = arg2;
775     } else {
776         s = slirp_lookup(mon, NULL);
777         redir_str = arg1;
778     }
779     if (s) {
780         Error *err = NULL;
781         if (slirp_hostfwd(s, redir_str, &err) < 0) {
782             error_report_err(err);
783         }
784     }
785 
786 }
787 
788 #ifndef _WIN32
789 
790 /* automatic user mode samba server configuration */
791 static void slirp_smb_cleanup(SlirpState *s)
792 {
793     int ret;
794 
795     if (s->smb_dir) {
796         gchar *cmd = g_strdup_printf("rm -rf %s", s->smb_dir);
797         ret = system(cmd);
798         if (ret == -1 || !WIFEXITED(ret)) {
799             error_report("'%s' failed.", cmd);
800         } else if (WEXITSTATUS(ret)) {
801             error_report("'%s' failed. Error code: %d",
802                          cmd, WEXITSTATUS(ret));
803         }
804         g_free(cmd);
805         g_free(s->smb_dir);
806         s->smb_dir = NULL;
807     }
808 }
809 
810 static int slirp_smb(SlirpState* s, const char *exported_dir,
811                      struct in_addr vserver_addr, Error **errp)
812 {
813     char *smb_conf;
814     char *smb_cmdline;
815     struct passwd *passwd;
816     FILE *f;
817 
818     passwd = getpwuid(geteuid());
819     if (!passwd) {
820         error_setg(errp, "Failed to retrieve user name");
821         return -1;
822     }
823 
824     if (access(CONFIG_SMBD_COMMAND, F_OK)) {
825         error_setg(errp, "Could not find '%s', please install it",
826                    CONFIG_SMBD_COMMAND);
827         return -1;
828     }
829 
830     if (access(exported_dir, R_OK | X_OK)) {
831         error_setg(errp, "Error accessing shared directory '%s': %s",
832                    exported_dir, strerror(errno));
833         return -1;
834     }
835 
836     s->smb_dir = g_dir_make_tmp("qemu-smb.XXXXXX", NULL);
837     if (!s->smb_dir) {
838         error_setg(errp, "Could not create samba server dir");
839         return -1;
840     }
841     smb_conf = g_strdup_printf("%s/%s", s->smb_dir, "smb.conf");
842 
843     f = fopen(smb_conf, "w");
844     if (!f) {
845         slirp_smb_cleanup(s);
846         error_setg(errp,
847                    "Could not create samba server configuration file '%s'",
848                     smb_conf);
849         g_free(smb_conf);
850         return -1;
851     }
852     fprintf(f,
853             "[global]\n"
854             "private dir=%s\n"
855             "interfaces=127.0.0.1\n"
856             "bind interfaces only=yes\n"
857             "pid directory=%s\n"
858             "lock directory=%s\n"
859             "state directory=%s\n"
860             "cache directory=%s\n"
861             "ncalrpc dir=%s/ncalrpc\n"
862             "log file=%s/log.smbd\n"
863             "smb passwd file=%s/smbpasswd\n"
864             "security = user\n"
865             "map to guest = Bad User\n"
866             "load printers = no\n"
867             "printing = bsd\n"
868             "disable spoolss = yes\n"
869             "usershare max shares = 0\n"
870             "[qemu]\n"
871             "path=%s\n"
872             "read only=no\n"
873             "guest ok=yes\n"
874             "force user=%s\n",
875             s->smb_dir,
876             s->smb_dir,
877             s->smb_dir,
878             s->smb_dir,
879             s->smb_dir,
880             s->smb_dir,
881             s->smb_dir,
882             s->smb_dir,
883             exported_dir,
884             passwd->pw_name
885             );
886     fclose(f);
887 
888     smb_cmdline = g_strdup_printf("%s -l %s -s %s",
889              CONFIG_SMBD_COMMAND, s->smb_dir, smb_conf);
890     g_free(smb_conf);
891 
892     if (slirp_add_exec(s->slirp, smb_cmdline, &vserver_addr, 139) < 0 ||
893         slirp_add_exec(s->slirp, smb_cmdline, &vserver_addr, 445) < 0) {
894         slirp_smb_cleanup(s);
895         g_free(smb_cmdline);
896         error_setg(errp, "Conflicting/invalid smbserver address");
897         return -1;
898     }
899     g_free(smb_cmdline);
900     return 0;
901 }
902 
903 #endif /* !defined(_WIN32) */
904 
905 static int guestfwd_can_read(void *opaque)
906 {
907     struct GuestFwd *fwd = opaque;
908     return slirp_socket_can_recv(fwd->slirp, fwd->server, fwd->port);
909 }
910 
911 static void guestfwd_read(void *opaque, const uint8_t *buf, int size)
912 {
913     struct GuestFwd *fwd = opaque;
914     slirp_socket_recv(fwd->slirp, fwd->server, fwd->port, buf, size);
915 }
916 
917 static ssize_t guestfwd_write(const void *buf, size_t len, void *chr)
918 {
919     return qemu_chr_fe_write_all(chr, buf, len);
920 }
921 
922 static int slirp_guestfwd(SlirpState *s, const char *config_str, Error **errp)
923 {
924     /* TODO: IPv6 */
925     struct in_addr server = { .s_addr = 0 };
926     struct GuestFwd *fwd;
927     const char *p;
928     char buf[128];
929     char *end;
930     int port;
931 
932     p = config_str;
933     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
934         goto fail_syntax;
935     }
936     if (strcmp(buf, "tcp") && buf[0] != '\0') {
937         goto fail_syntax;
938     }
939     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
940         goto fail_syntax;
941     }
942     if (buf[0] != '\0' && !inet_aton(buf, &server)) {
943         goto fail_syntax;
944     }
945     if (get_str_sep(buf, sizeof(buf), &p, '-') < 0) {
946         goto fail_syntax;
947     }
948     port = strtol(buf, &end, 10);
949     if (*end != '\0' || port < 1 || port > 65535) {
950         goto fail_syntax;
951     }
952 
953     snprintf(buf, sizeof(buf), "guestfwd.tcp.%d", port);
954 
955     if (g_str_has_prefix(p, "cmd:")) {
956         if (slirp_add_exec(s->slirp, &p[4], &server, port) < 0) {
957             error_setg(errp, "Conflicting/invalid host:port in guest "
958                        "forwarding rule '%s'", config_str);
959             return -1;
960         }
961     } else {
962         Error *err = NULL;
963         /*
964          * FIXME: sure we want to support implicit
965          * muxed monitors here?
966          */
967         Chardev *chr = qemu_chr_new_mux_mon(buf, p, NULL);
968 
969         if (!chr) {
970             error_setg(errp, "Could not open guest forwarding device '%s'",
971                        buf);
972             return -1;
973         }
974 
975         fwd = g_new(struct GuestFwd, 1);
976         qemu_chr_fe_init(&fwd->hd, chr, &err);
977         if (err) {
978             error_propagate(errp, err);
979             object_unparent(OBJECT(chr));
980             g_free(fwd);
981             return -1;
982         }
983 
984         if (slirp_add_guestfwd(s->slirp, guestfwd_write, &fwd->hd,
985                                &server, port) < 0) {
986             error_setg(errp, "Conflicting/invalid host:port in guest "
987                        "forwarding rule '%s'", config_str);
988             qemu_chr_fe_deinit(&fwd->hd, true);
989             g_free(fwd);
990             return -1;
991         }
992         fwd->server = server;
993         fwd->port = port;
994         fwd->slirp = s->slirp;
995 
996         qemu_chr_fe_set_handlers(&fwd->hd, guestfwd_can_read, guestfwd_read,
997                                  NULL, NULL, fwd, NULL, true);
998         s->fwd = g_slist_append(s->fwd, fwd);
999     }
1000     return 0;
1001 
1002  fail_syntax:
1003     error_setg(errp, "Invalid guest forwarding rule '%s'", config_str);
1004     return -1;
1005 }
1006 
1007 void hmp_info_usernet(Monitor *mon, const QDict *qdict)
1008 {
1009     SlirpState *s;
1010 
1011     QTAILQ_FOREACH(s, &slirp_stacks, entry) {
1012         int id;
1013         bool got_hub_id = net_hub_id_for_client(&s->nc, &id) == 0;
1014         char *info = slirp_connection_info(s->slirp);
1015         monitor_printf(mon, "Hub %d (%s):\n%s",
1016                        got_hub_id ? id : -1,
1017                        s->nc.name, info);
1018         g_free(info);
1019     }
1020 }
1021 
1022 static void
1023 net_init_slirp_configs(const StringList *fwd, int flags)
1024 {
1025     while (fwd) {
1026         struct slirp_config_str *config;
1027 
1028         config = g_malloc0(sizeof(*config));
1029         pstrcpy(config->str, sizeof(config->str), fwd->value->str);
1030         config->flags = flags;
1031         config->next = slirp_configs;
1032         slirp_configs = config;
1033 
1034         fwd = fwd->next;
1035     }
1036 }
1037 
1038 static const char **slirp_dnssearch(const StringList *dnsname)
1039 {
1040     const StringList *c = dnsname;
1041     size_t i = 0, num_opts = 0;
1042     const char **ret;
1043 
1044     while (c) {
1045         num_opts++;
1046         c = c->next;
1047     }
1048 
1049     if (num_opts == 0) {
1050         return NULL;
1051     }
1052 
1053     ret = g_malloc((num_opts + 1) * sizeof(*ret));
1054     c = dnsname;
1055     while (c) {
1056         ret[i++] = c->value->str;
1057         c = c->next;
1058     }
1059     ret[i] = NULL;
1060     return ret;
1061 }
1062 
1063 int net_init_slirp(const Netdev *netdev, const char *name,
1064                    NetClientState *peer, Error **errp)
1065 {
1066     struct slirp_config_str *config;
1067     char *vnet;
1068     int ret;
1069     const NetdevUserOptions *user;
1070     const char **dnssearch;
1071     bool ipv4 = true, ipv6 = true;
1072 
1073     assert(netdev->type == NET_CLIENT_DRIVER_USER);
1074     user = &netdev->u.user;
1075 
1076     if ((user->has_ipv6 && user->ipv6 && !user->has_ipv4) ||
1077         (user->has_ipv4 && !user->ipv4)) {
1078         ipv4 = 0;
1079     }
1080     if ((user->has_ipv4 && user->ipv4 && !user->has_ipv6) ||
1081         (user->has_ipv6 && !user->ipv6)) {
1082         ipv6 = 0;
1083     }
1084 
1085     vnet = user->has_net ? g_strdup(user->net) :
1086            user->has_ip  ? g_strdup_printf("%s/24", user->ip) :
1087            NULL;
1088 
1089     dnssearch = slirp_dnssearch(user->dnssearch);
1090 
1091     /* all optional fields are initialized to "all bits zero" */
1092 
1093     net_init_slirp_configs(user->hostfwd, SLIRP_CFG_HOSTFWD);
1094     net_init_slirp_configs(user->guestfwd, 0);
1095 
1096     ret = net_slirp_init(peer, "user", name, user->q_restrict,
1097                          ipv4, vnet, user->host,
1098                          ipv6, user->ipv6_prefix, user->ipv6_prefixlen,
1099                          user->ipv6_host, user->hostname, user->tftp,
1100                          user->bootfile, user->dhcpstart,
1101                          user->dns, user->ipv6_dns, user->smb,
1102                          user->smbserver, dnssearch, user->domainname,
1103                          user->tftp_server_name, errp);
1104 
1105     while (slirp_configs) {
1106         config = slirp_configs;
1107         slirp_configs = config->next;
1108         g_free(config);
1109     }
1110 
1111     g_free(vnet);
1112     g_free(dnssearch);
1113 
1114     return ret;
1115 }
1116