xref: /openbmc/qemu/net/slirp.c (revision d901eff3) 
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 "net/slirp.h"
25 
26 #include "config-host.h"
27 
28 #ifndef _WIN32
29 #include <pwd.h>
30 #include <sys/wait.h>
31 #endif
32 #include "net.h"
33 #include "monitor.h"
34 #include "qemu_socket.h"
35 #include "slirp/libslirp.h"
36 
37 static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
38 {
39     const char *p, *p1;
40     int len;
41     p = *pp;
42     p1 = strchr(p, sep);
43     if (!p1)
44         return -1;
45     len = p1 - p;
46     p1++;
47     if (buf_size > 0) {
48         if (len > buf_size - 1)
49             len = buf_size - 1;
50         memcpy(buf, p, len);
51         buf[len] = '\0';
52     }
53     *pp = p1;
54     return 0;
55 }
56 
57 /* slirp network adapter */
58 
59 #define SLIRP_CFG_HOSTFWD 1
60 #define SLIRP_CFG_LEGACY  2
61 
62 struct slirp_config_str {
63     struct slirp_config_str *next;
64     int flags;
65     char str[1024];
66     int legacy_format;
67 };
68 
69 typedef struct SlirpState {
70     VLANClientState nc;
71     QTAILQ_ENTRY(SlirpState) entry;
72     Slirp *slirp;
73 #ifndef _WIN32
74     char smb_dir[128];
75 #endif
76 } SlirpState;
77 
78 static struct slirp_config_str *slirp_configs;
79 const char *legacy_tftp_prefix;
80 const char *legacy_bootp_filename;
81 static QTAILQ_HEAD(slirp_stacks, SlirpState) slirp_stacks =
82     QTAILQ_HEAD_INITIALIZER(slirp_stacks);
83 
84 static int slirp_hostfwd(SlirpState *s, const char *redir_str,
85                          int legacy_format);
86 static int slirp_guestfwd(SlirpState *s, const char *config_str,
87                           int legacy_format);
88 
89 #ifndef _WIN32
90 static const char *legacy_smb_export;
91 
92 static int slirp_smb(SlirpState *s, const char *exported_dir,
93                      struct in_addr vserver_addr);
94 static void slirp_smb_cleanup(SlirpState *s);
95 #else
96 static inline void slirp_smb_cleanup(SlirpState *s) { }
97 #endif
98 
99 int slirp_can_output(void *opaque)
100 {
101     SlirpState *s = opaque;
102 
103     return qemu_can_send_packet(&s->nc);
104 }
105 
106 void slirp_output(void *opaque, const uint8_t *pkt, int pkt_len)
107 {
108     SlirpState *s = opaque;
109 
110     qemu_send_packet(&s->nc, pkt, pkt_len);
111 }
112 
113 static ssize_t net_slirp_receive(VLANClientState *nc, const uint8_t *buf, size_t size)
114 {
115     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
116 
117     slirp_input(s->slirp, buf, size);
118 
119     return size;
120 }
121 
122 static void net_slirp_cleanup(VLANClientState *nc)
123 {
124     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
125 
126     slirp_cleanup(s->slirp);
127     slirp_smb_cleanup(s);
128     QTAILQ_REMOVE(&slirp_stacks, s, entry);
129 }
130 
131 static NetClientInfo net_slirp_info = {
132     .type = NET_CLIENT_OPTIONS_KIND_USER,
133     .size = sizeof(SlirpState),
134     .receive = net_slirp_receive,
135     .cleanup = net_slirp_cleanup,
136 };
137 
138 static int net_slirp_init(VLANState *vlan, const char *model,
139                           const char *name, int restricted,
140                           const char *vnetwork, const char *vhost,
141                           const char *vhostname, const char *tftp_export,
142                           const char *bootfile, const char *vdhcp_start,
143                           const char *vnameserver, const char *smb_export,
144                           const char *vsmbserver)
145 {
146     /* default settings according to historic slirp */
147     struct in_addr net  = { .s_addr = htonl(0x0a000200) }; /* 10.0.2.0 */
148     struct in_addr mask = { .s_addr = htonl(0xffffff00) }; /* 255.255.255.0 */
149     struct in_addr host = { .s_addr = htonl(0x0a000202) }; /* 10.0.2.2 */
150     struct in_addr dhcp = { .s_addr = htonl(0x0a00020f) }; /* 10.0.2.15 */
151     struct in_addr dns  = { .s_addr = htonl(0x0a000203) }; /* 10.0.2.3 */
152 #ifndef _WIN32
153     struct in_addr smbsrv = { .s_addr = 0 };
154 #endif
155     VLANClientState *nc;
156     SlirpState *s;
157     char buf[20];
158     uint32_t addr;
159     int shift;
160     char *end;
161     struct slirp_config_str *config;
162 
163     if (!tftp_export) {
164         tftp_export = legacy_tftp_prefix;
165     }
166     if (!bootfile) {
167         bootfile = legacy_bootp_filename;
168     }
169 
170     if (vnetwork) {
171         if (get_str_sep(buf, sizeof(buf), &vnetwork, '/') < 0) {
172             if (!inet_aton(vnetwork, &net)) {
173                 return -1;
174             }
175             addr = ntohl(net.s_addr);
176             if (!(addr & 0x80000000)) {
177                 mask.s_addr = htonl(0xff000000); /* class A */
178             } else if ((addr & 0xfff00000) == 0xac100000) {
179                 mask.s_addr = htonl(0xfff00000); /* priv. 172.16.0.0/12 */
180             } else if ((addr & 0xc0000000) == 0x80000000) {
181                 mask.s_addr = htonl(0xffff0000); /* class B */
182             } else if ((addr & 0xffff0000) == 0xc0a80000) {
183                 mask.s_addr = htonl(0xffff0000); /* priv. 192.168.0.0/16 */
184             } else if ((addr & 0xffff0000) == 0xc6120000) {
185                 mask.s_addr = htonl(0xfffe0000); /* tests 198.18.0.0/15 */
186             } else if ((addr & 0xe0000000) == 0xe0000000) {
187                 mask.s_addr = htonl(0xffffff00); /* class C */
188             } else {
189                 mask.s_addr = htonl(0xfffffff0); /* multicast/reserved */
190             }
191         } else {
192             if (!inet_aton(buf, &net)) {
193                 return -1;
194             }
195             shift = strtol(vnetwork, &end, 10);
196             if (*end != '\0') {
197                 if (!inet_aton(vnetwork, &mask)) {
198                     return -1;
199                 }
200             } else if (shift < 4 || shift > 32) {
201                 return -1;
202             } else {
203                 mask.s_addr = htonl(0xffffffff << (32 - shift));
204             }
205         }
206         net.s_addr &= mask.s_addr;
207         host.s_addr = net.s_addr | (htonl(0x0202) & ~mask.s_addr);
208         dhcp.s_addr = net.s_addr | (htonl(0x020f) & ~mask.s_addr);
209         dns.s_addr  = net.s_addr | (htonl(0x0203) & ~mask.s_addr);
210     }
211 
212     if (vhost && !inet_aton(vhost, &host)) {
213         return -1;
214     }
215     if ((host.s_addr & mask.s_addr) != net.s_addr) {
216         return -1;
217     }
218 
219     if (vdhcp_start && !inet_aton(vdhcp_start, &dhcp)) {
220         return -1;
221     }
222     if ((dhcp.s_addr & mask.s_addr) != net.s_addr ||
223         dhcp.s_addr == host.s_addr || dhcp.s_addr == dns.s_addr) {
224         return -1;
225     }
226 
227     if (vnameserver && !inet_aton(vnameserver, &dns)) {
228         return -1;
229     }
230     if ((dns.s_addr & mask.s_addr) != net.s_addr ||
231         dns.s_addr == host.s_addr) {
232         return -1;
233     }
234 
235 #ifndef _WIN32
236     if (vsmbserver && !inet_aton(vsmbserver, &smbsrv)) {
237         return -1;
238     }
239 #endif
240 
241     nc = qemu_new_net_client(&net_slirp_info, vlan, NULL, model, name);
242 
243     snprintf(nc->info_str, sizeof(nc->info_str),
244              "net=%s,restrict=%s", inet_ntoa(net),
245              restricted ? "on" : "off");
246 
247     s = DO_UPCAST(SlirpState, nc, nc);
248 
249     s->slirp = slirp_init(restricted, net, mask, host, vhostname,
250                           tftp_export, bootfile, dhcp, dns, s);
251     QTAILQ_INSERT_TAIL(&slirp_stacks, s, entry);
252 
253     for (config = slirp_configs; config; config = config->next) {
254         if (config->flags & SLIRP_CFG_HOSTFWD) {
255             if (slirp_hostfwd(s, config->str,
256                               config->flags & SLIRP_CFG_LEGACY) < 0)
257                 goto error;
258         } else {
259             if (slirp_guestfwd(s, config->str,
260                                config->flags & SLIRP_CFG_LEGACY) < 0)
261                 goto error;
262         }
263     }
264 #ifndef _WIN32
265     if (!smb_export) {
266         smb_export = legacy_smb_export;
267     }
268     if (smb_export) {
269         if (slirp_smb(s, smb_export, smbsrv) < 0)
270             goto error;
271     }
272 #endif
273 
274     return 0;
275 
276 error:
277     qemu_del_vlan_client(nc);
278     return -1;
279 }
280 
281 static SlirpState *slirp_lookup(Monitor *mon, const char *vlan,
282                                 const char *stack)
283 {
284 
285     if (vlan) {
286         VLANClientState *nc;
287         nc = qemu_find_vlan_client_by_name(mon, strtol(vlan, NULL, 0), stack);
288         if (!nc) {
289             return NULL;
290         }
291         if (strcmp(nc->model, "user")) {
292             monitor_printf(mon, "invalid device specified\n");
293             return NULL;
294         }
295         return DO_UPCAST(SlirpState, nc, nc);
296     } else {
297         if (QTAILQ_EMPTY(&slirp_stacks)) {
298             monitor_printf(mon, "user mode network stack not in use\n");
299             return NULL;
300         }
301         return QTAILQ_FIRST(&slirp_stacks);
302     }
303 }
304 
305 void net_slirp_hostfwd_remove(Monitor *mon, const QDict *qdict)
306 {
307     struct in_addr host_addr = { .s_addr = INADDR_ANY };
308     int host_port;
309     char buf[256];
310     const char *src_str, *p;
311     SlirpState *s;
312     int is_udp = 0;
313     int err;
314     const char *arg1 = qdict_get_str(qdict, "arg1");
315     const char *arg2 = qdict_get_try_str(qdict, "arg2");
316     const char *arg3 = qdict_get_try_str(qdict, "arg3");
317 
318     if (arg2) {
319         s = slirp_lookup(mon, arg1, arg2);
320         src_str = arg3;
321     } else {
322         s = slirp_lookup(mon, NULL, NULL);
323         src_str = arg1;
324     }
325     if (!s) {
326         return;
327     }
328 
329     p = src_str;
330     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
331         goto fail_syntax;
332     }
333 
334     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
335         is_udp = 0;
336     } else if (!strcmp(buf, "udp")) {
337         is_udp = 1;
338     } else {
339         goto fail_syntax;
340     }
341 
342     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
343         goto fail_syntax;
344     }
345     if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
346         goto fail_syntax;
347     }
348 
349     host_port = atoi(p);
350 
351     err = slirp_remove_hostfwd(QTAILQ_FIRST(&slirp_stacks)->slirp, is_udp,
352                                host_addr, host_port);
353 
354     monitor_printf(mon, "host forwarding rule for %s %s\n", src_str,
355                    err ? "not found" : "removed");
356     return;
357 
358  fail_syntax:
359     monitor_printf(mon, "invalid format\n");
360 }
361 
362 static int slirp_hostfwd(SlirpState *s, const char *redir_str,
363                          int legacy_format)
364 {
365     struct in_addr host_addr = { .s_addr = INADDR_ANY };
366     struct in_addr guest_addr = { .s_addr = 0 };
367     int host_port, guest_port;
368     const char *p;
369     char buf[256];
370     int is_udp;
371     char *end;
372 
373     p = redir_str;
374     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
375         goto fail_syntax;
376     }
377     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
378         is_udp = 0;
379     } else if (!strcmp(buf, "udp")) {
380         is_udp = 1;
381     } else {
382         goto fail_syntax;
383     }
384 
385     if (!legacy_format) {
386         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
387             goto fail_syntax;
388         }
389         if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
390             goto fail_syntax;
391         }
392     }
393 
394     if (get_str_sep(buf, sizeof(buf), &p, legacy_format ? ':' : '-') < 0) {
395         goto fail_syntax;
396     }
397     host_port = strtol(buf, &end, 0);
398     if (*end != '\0' || host_port < 1 || host_port > 65535) {
399         goto fail_syntax;
400     }
401 
402     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
403         goto fail_syntax;
404     }
405     if (buf[0] != '\0' && !inet_aton(buf, &guest_addr)) {
406         goto fail_syntax;
407     }
408 
409     guest_port = strtol(p, &end, 0);
410     if (*end != '\0' || guest_port < 1 || guest_port > 65535) {
411         goto fail_syntax;
412     }
413 
414     if (slirp_add_hostfwd(s->slirp, is_udp, host_addr, host_port, guest_addr,
415                           guest_port) < 0) {
416         error_report("could not set up host forwarding rule '%s'",
417                      redir_str);
418         return -1;
419     }
420     return 0;
421 
422  fail_syntax:
423     error_report("invalid host forwarding rule '%s'", redir_str);
424     return -1;
425 }
426 
427 void net_slirp_hostfwd_add(Monitor *mon, const QDict *qdict)
428 {
429     const char *redir_str;
430     SlirpState *s;
431     const char *arg1 = qdict_get_str(qdict, "arg1");
432     const char *arg2 = qdict_get_try_str(qdict, "arg2");
433     const char *arg3 = qdict_get_try_str(qdict, "arg3");
434 
435     if (arg2) {
436         s = slirp_lookup(mon, arg1, arg2);
437         redir_str = arg3;
438     } else {
439         s = slirp_lookup(mon, NULL, NULL);
440         redir_str = arg1;
441     }
442     if (s) {
443         slirp_hostfwd(s, redir_str, 0);
444     }
445 
446 }
447 
448 int net_slirp_redir(const char *redir_str)
449 {
450     struct slirp_config_str *config;
451 
452     if (QTAILQ_EMPTY(&slirp_stacks)) {
453         config = g_malloc(sizeof(*config));
454         pstrcpy(config->str, sizeof(config->str), redir_str);
455         config->flags = SLIRP_CFG_HOSTFWD | SLIRP_CFG_LEGACY;
456         config->next = slirp_configs;
457         slirp_configs = config;
458         return 0;
459     }
460 
461     return slirp_hostfwd(QTAILQ_FIRST(&slirp_stacks), redir_str, 1);
462 }
463 
464 #ifndef _WIN32
465 
466 /* automatic user mode samba server configuration */
467 static void slirp_smb_cleanup(SlirpState *s)
468 {
469     char cmd[128];
470     int ret;
471 
472     if (s->smb_dir[0] != '\0') {
473         snprintf(cmd, sizeof(cmd), "rm -rf %s", s->smb_dir);
474         ret = system(cmd);
475         if (ret == -1 || !WIFEXITED(ret)) {
476             error_report("'%s' failed.", cmd);
477         } else if (WEXITSTATUS(ret)) {
478             error_report("'%s' failed. Error code: %d",
479                          cmd, WEXITSTATUS(ret));
480         }
481         s->smb_dir[0] = '\0';
482     }
483 }
484 
485 static int slirp_smb(SlirpState* s, const char *exported_dir,
486                      struct in_addr vserver_addr)
487 {
488     static int instance;
489     char smb_conf[128];
490     char smb_cmdline[128];
491     struct passwd *passwd;
492     FILE *f;
493 
494     passwd = getpwuid(geteuid());
495     if (!passwd) {
496         error_report("failed to retrieve user name");
497         return -1;
498     }
499 
500     if (access(CONFIG_SMBD_COMMAND, F_OK)) {
501         error_report("could not find '%s', please install it",
502                      CONFIG_SMBD_COMMAND);
503         return -1;
504     }
505 
506     if (access(exported_dir, R_OK | X_OK)) {
507         error_report("error accessing shared directory '%s': %s",
508                      exported_dir, strerror(errno));
509         return -1;
510     }
511 
512     snprintf(s->smb_dir, sizeof(s->smb_dir), "/tmp/qemu-smb.%ld-%d",
513              (long)getpid(), instance++);
514     if (mkdir(s->smb_dir, 0700) < 0) {
515         error_report("could not create samba server dir '%s'", s->smb_dir);
516         return -1;
517     }
518     snprintf(smb_conf, sizeof(smb_conf), "%s/%s", s->smb_dir, "smb.conf");
519 
520     f = fopen(smb_conf, "w");
521     if (!f) {
522         slirp_smb_cleanup(s);
523         error_report("could not create samba server configuration file '%s'",
524                      smb_conf);
525         return -1;
526     }
527     fprintf(f,
528             "[global]\n"
529             "private dir=%s\n"
530             "socket address=127.0.0.1\n"
531             "pid directory=%s\n"
532             "lock directory=%s\n"
533             "state directory=%s\n"
534             "log file=%s/log.smbd\n"
535             "smb passwd file=%s/smbpasswd\n"
536             "security = share\n"
537             "[qemu]\n"
538             "path=%s\n"
539             "read only=no\n"
540             "guest ok=yes\n"
541             "force user=%s\n",
542             s->smb_dir,
543             s->smb_dir,
544             s->smb_dir,
545             s->smb_dir,
546             s->smb_dir,
547             s->smb_dir,
548             exported_dir,
549             passwd->pw_name
550             );
551     fclose(f);
552 
553     snprintf(smb_cmdline, sizeof(smb_cmdline), "%s -s %s",
554              CONFIG_SMBD_COMMAND, smb_conf);
555 
556     if (slirp_add_exec(s->slirp, 0, smb_cmdline, &vserver_addr, 139) < 0) {
557         slirp_smb_cleanup(s);
558         error_report("conflicting/invalid smbserver address");
559         return -1;
560     }
561     return 0;
562 }
563 
564 /* automatic user mode samba server configuration (legacy interface) */
565 int net_slirp_smb(const char *exported_dir)
566 {
567     struct in_addr vserver_addr = { .s_addr = 0 };
568 
569     if (legacy_smb_export) {
570         fprintf(stderr, "-smb given twice\n");
571         return -1;
572     }
573     legacy_smb_export = exported_dir;
574     if (!QTAILQ_EMPTY(&slirp_stacks)) {
575         return slirp_smb(QTAILQ_FIRST(&slirp_stacks), exported_dir,
576                          vserver_addr);
577     }
578     return 0;
579 }
580 
581 #endif /* !defined(_WIN32) */
582 
583 struct GuestFwd {
584     CharDriverState *hd;
585     struct in_addr server;
586     int port;
587     Slirp *slirp;
588 };
589 
590 static int guestfwd_can_read(void *opaque)
591 {
592     struct GuestFwd *fwd = opaque;
593     return slirp_socket_can_recv(fwd->slirp, fwd->server, fwd->port);
594 }
595 
596 static void guestfwd_read(void *opaque, const uint8_t *buf, int size)
597 {
598     struct GuestFwd *fwd = opaque;
599     slirp_socket_recv(fwd->slirp, fwd->server, fwd->port, buf, size);
600 }
601 
602 static int slirp_guestfwd(SlirpState *s, const char *config_str,
603                           int legacy_format)
604 {
605     struct in_addr server = { .s_addr = 0 };
606     struct GuestFwd *fwd;
607     const char *p;
608     char buf[128];
609     char *end;
610     int port;
611 
612     p = config_str;
613     if (legacy_format) {
614         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
615             goto fail_syntax;
616         }
617     } else {
618         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
619             goto fail_syntax;
620         }
621         if (strcmp(buf, "tcp") && buf[0] != '\0') {
622             goto fail_syntax;
623         }
624         if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
625             goto fail_syntax;
626         }
627         if (buf[0] != '\0' && !inet_aton(buf, &server)) {
628             goto fail_syntax;
629         }
630         if (get_str_sep(buf, sizeof(buf), &p, '-') < 0) {
631             goto fail_syntax;
632         }
633     }
634     port = strtol(buf, &end, 10);
635     if (*end != '\0' || port < 1 || port > 65535) {
636         goto fail_syntax;
637     }
638 
639     fwd = g_malloc(sizeof(struct GuestFwd));
640     snprintf(buf, sizeof(buf), "guestfwd.tcp.%d", port);
641 
642     if ((strlen(p) > 4) && !strncmp(p, "cmd:", 4)) {
643         if (slirp_add_exec(s->slirp, 0, &p[4], &server, port) < 0) {
644             error_report("conflicting/invalid host:port in guest forwarding "
645                          "rule '%s'", config_str);
646             g_free(fwd);
647             return -1;
648         }
649     } else {
650         fwd->hd = qemu_chr_new(buf, p, NULL);
651         if (!fwd->hd) {
652             error_report("could not open guest forwarding device '%s'", buf);
653             g_free(fwd);
654             return -1;
655         }
656 
657         if (slirp_add_exec(s->slirp, 3, fwd->hd, &server, port) < 0) {
658             error_report("conflicting/invalid host:port in guest forwarding "
659                          "rule '%s'", config_str);
660             g_free(fwd);
661             return -1;
662         }
663         fwd->server = server;
664         fwd->port = port;
665         fwd->slirp = s->slirp;
666 
667         qemu_chr_add_handlers(fwd->hd, guestfwd_can_read, guestfwd_read,
668                               NULL, fwd);
669     }
670     return 0;
671 
672  fail_syntax:
673     error_report("invalid guest forwarding rule '%s'", config_str);
674     return -1;
675 }
676 
677 void do_info_usernet(Monitor *mon)
678 {
679     SlirpState *s;
680 
681     QTAILQ_FOREACH(s, &slirp_stacks, entry) {
682         monitor_printf(mon, "VLAN %d (%s):\n",
683                        s->nc.vlan ? s->nc.vlan->id : -1,
684                        s->nc.name);
685         slirp_connection_info(s->slirp, mon);
686     }
687 }
688 
689 static void
690 net_init_slirp_configs(const StringList *fwd, int flags)
691 {
692     while (fwd) {
693         struct slirp_config_str *config;
694 
695         config = g_malloc0(sizeof(*config));
696         pstrcpy(config->str, sizeof(config->str), fwd->value->str);
697         config->flags = flags;
698         config->next = slirp_configs;
699         slirp_configs = config;
700 
701         fwd = fwd->next;
702     }
703 }
704 
705 int net_init_slirp(const NetClientOptions *opts, const char *name,
706                    VLANState *vlan)
707 {
708     struct slirp_config_str *config;
709     char *vnet;
710     int ret;
711     const NetdevUserOptions *user;
712 
713     assert(opts->kind == NET_CLIENT_OPTIONS_KIND_USER);
714     user = opts->user;
715 
716     vnet = user->has_net ? g_strdup(user->net) :
717            user->has_ip  ? g_strdup_printf("%s/24", user->ip) :
718            NULL;
719 
720     /* all optional fields are initialized to "all bits zero" */
721 
722     net_init_slirp_configs(user->hostfwd, SLIRP_CFG_HOSTFWD);
723     net_init_slirp_configs(user->guestfwd, 0);
724 
725     ret = net_slirp_init(vlan, "user", name, user->restrict, vnet, user->host,
726                          user->hostname, user->tftp, user->bootfile,
727                          user->dhcpstart, user->dns, user->smb,
728                          user->smbserver);
729 
730     while (slirp_configs) {
731         config = slirp_configs;
732         slirp_configs = config->next;
733         g_free(config);
734     }
735 
736     g_free(vnet);
737 
738     return ret;
739 }
740 
741 int net_slirp_parse_legacy(QemuOptsList *opts_list, const char *optarg, int *ret)
742 {
743     if (strcmp(opts_list->name, "net") != 0 ||
744         strncmp(optarg, "channel,", strlen("channel,")) != 0) {
745         return 0;
746     }
747 
748     /* handle legacy -net channel,port:chr */
749     optarg += strlen("channel,");
750 
751     if (QTAILQ_EMPTY(&slirp_stacks)) {
752         struct slirp_config_str *config;
753 
754         config = g_malloc(sizeof(*config));
755         pstrcpy(config->str, sizeof(config->str), optarg);
756         config->flags = SLIRP_CFG_LEGACY;
757         config->next = slirp_configs;
758         slirp_configs = config;
759         *ret = 0;
760     } else {
761         *ret = slirp_guestfwd(QTAILQ_FIRST(&slirp_stacks), optarg, 1);
762     }
763 
764     return 1;
765 }
766 
767