xref: /openbmc/qemu/util/qemu-sockets.c (revision 2ba60ec1)
1 /*
2  *  inet and unix socket functions for qemu
3  *
4  *  (c) 2008 Gerd Hoffmann <kraxel@redhat.com>
5  *
6  *  This program is free software; you can redistribute it and/or modify
7  *  it under the terms of the GNU General Public License as published by
8  *  the Free Software Foundation; under version 2 of the License.
9  *
10  *  This program is distributed in the hope that it will be useful,
11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  *  GNU General Public License for more details.
14  *
15  * Contributions after 2012-01-13 are licensed under the terms of the
16  * GNU GPL, version 2 or (at your option) any later version.
17  */
18 #include "qemu/osdep.h"
19 
20 #ifdef CONFIG_AF_VSOCK
21 #include <linux/vm_sockets.h>
22 #endif /* CONFIG_AF_VSOCK */
23 
24 #include "monitor/monitor.h"
25 #include "qapi/clone-visitor.h"
26 #include "qapi/error.h"
27 #include "qemu/sockets.h"
28 #include "qemu/main-loop.h"
29 #include "qapi/qobject-input-visitor.h"
30 #include "qapi/qobject-output-visitor.h"
31 #include "qapi-visit.h"
32 #include "qemu/cutils.h"
33 
34 #ifndef AI_ADDRCONFIG
35 # define AI_ADDRCONFIG 0
36 #endif
37 
38 #ifndef AI_V4MAPPED
39 # define AI_V4MAPPED 0
40 #endif
41 
42 #ifndef AI_NUMERICSERV
43 # define AI_NUMERICSERV 0
44 #endif
45 
46 
47 static int inet_getport(struct addrinfo *e)
48 {
49     struct sockaddr_in *i4;
50     struct sockaddr_in6 *i6;
51 
52     switch (e->ai_family) {
53     case PF_INET6:
54         i6 = (void*)e->ai_addr;
55         return ntohs(i6->sin6_port);
56     case PF_INET:
57         i4 = (void*)e->ai_addr;
58         return ntohs(i4->sin_port);
59     default:
60         return 0;
61     }
62 }
63 
64 static void inet_setport(struct addrinfo *e, int port)
65 {
66     struct sockaddr_in *i4;
67     struct sockaddr_in6 *i6;
68 
69     switch (e->ai_family) {
70     case PF_INET6:
71         i6 = (void*)e->ai_addr;
72         i6->sin6_port = htons(port);
73         break;
74     case PF_INET:
75         i4 = (void*)e->ai_addr;
76         i4->sin_port = htons(port);
77         break;
78     }
79 }
80 
81 NetworkAddressFamily inet_netfamily(int family)
82 {
83     switch (family) {
84     case PF_INET6: return NETWORK_ADDRESS_FAMILY_IPV6;
85     case PF_INET:  return NETWORK_ADDRESS_FAMILY_IPV4;
86     case PF_UNIX:  return NETWORK_ADDRESS_FAMILY_UNIX;
87 #ifdef CONFIG_AF_VSOCK
88     case PF_VSOCK: return NETWORK_ADDRESS_FAMILY_VSOCK;
89 #endif /* CONFIG_AF_VSOCK */
90     }
91     return NETWORK_ADDRESS_FAMILY_UNKNOWN;
92 }
93 
94 /*
95  * Matrix we're trying to apply
96  *
97  *  ipv4  ipv6   family
98  *   -     -       PF_UNSPEC
99  *   -     f       PF_INET
100  *   -     t       PF_INET6
101  *   f     -       PF_INET6
102  *   f     f       <error>
103  *   f     t       PF_INET6
104  *   t     -       PF_INET
105  *   t     f       PF_INET
106  *   t     t       PF_INET6/PF_UNSPEC
107  *
108  * NB, this matrix is only about getting the necessary results
109  * from getaddrinfo(). Some of the cases require further work
110  * after reading results from getaddrinfo in order to fully
111  * apply the logic the end user wants.
112  *
113  * In the first and last cases, we must set IPV6_V6ONLY=0
114  * when binding, to allow a single listener to potentially
115  * accept both IPv4+6 addresses.
116  */
117 int inet_ai_family_from_address(InetSocketAddress *addr,
118                                 Error **errp)
119 {
120     if (addr->has_ipv6 && addr->has_ipv4 &&
121         !addr->ipv6 && !addr->ipv4) {
122         error_setg(errp, "Cannot disable IPv4 and IPv6 at same time");
123         return PF_UNSPEC;
124     }
125     if ((addr->has_ipv6 && addr->ipv6) && (addr->has_ipv4 && addr->ipv4)) {
126         /*
127          * Some backends can only do a single listener. In that case
128          * we want empty hostname to resolve to "::" and then use the
129          * flag IPV6_V6ONLY==0 to get both protocols on 1 socket. This
130          * doesn't work for addresses other than "", so they're just
131          * inevitably broken until multiple listeners can be used,
132          * and thus we honour getaddrinfo automatic protocol detection
133          * Once all backends do multi-listener, remove the PF_INET6
134          * branch entirely.
135          */
136         if (!addr->host || g_str_equal(addr->host, "")) {
137             return PF_INET6;
138         } else {
139             return PF_UNSPEC;
140         }
141     }
142     if ((addr->has_ipv6 && addr->ipv6) || (addr->has_ipv4 && !addr->ipv4)) {
143         return PF_INET6;
144     }
145     if ((addr->has_ipv4 && addr->ipv4) || (addr->has_ipv6 && !addr->ipv6)) {
146         return PF_INET;
147     }
148     return PF_UNSPEC;
149 }
150 
151 static int create_fast_reuse_socket(struct addrinfo *e)
152 {
153     int slisten = qemu_socket(e->ai_family, e->ai_socktype, e->ai_protocol);
154     if (slisten < 0) {
155         return -1;
156     }
157     socket_set_fast_reuse(slisten);
158     return slisten;
159 }
160 
161 static int try_bind(int socket, InetSocketAddress *saddr, struct addrinfo *e)
162 {
163 #ifndef IPV6_V6ONLY
164     return bind(socket, e->ai_addr, e->ai_addrlen);
165 #else
166     /*
167      * Deals with first & last cases in matrix in comment
168      * for inet_ai_family_from_address().
169      */
170     int v6only =
171         ((!saddr->has_ipv4 && !saddr->has_ipv6) ||
172          (saddr->has_ipv4 && saddr->ipv4 &&
173           saddr->has_ipv6 && saddr->ipv6)) ? 0 : 1;
174     int stat;
175 
176  rebind:
177     if (e->ai_family == PF_INET6) {
178         qemu_setsockopt(socket, IPPROTO_IPV6, IPV6_V6ONLY, &v6only,
179                         sizeof(v6only));
180     }
181 
182     stat = bind(socket, e->ai_addr, e->ai_addrlen);
183     if (!stat) {
184         return 0;
185     }
186 
187     /* If we got EADDRINUSE from an IPv6 bind & v6only is unset,
188      * it could be that the IPv4 port is already claimed, so retry
189      * with v6only set
190      */
191     if (e->ai_family == PF_INET6 && errno == EADDRINUSE && !v6only) {
192         v6only = 1;
193         goto rebind;
194     }
195     return stat;
196 #endif
197 }
198 
199 static int inet_listen_saddr(InetSocketAddress *saddr,
200                              int port_offset,
201                              bool update_addr,
202                              Error **errp)
203 {
204     struct addrinfo ai,*res,*e;
205     char port[33];
206     char uaddr[INET6_ADDRSTRLEN+1];
207     char uport[33];
208     int rc, port_min, port_max, p;
209     int slisten = -1;
210     int saved_errno = 0;
211     bool socket_created = false;
212     Error *err = NULL;
213 
214     memset(&ai,0, sizeof(ai));
215     ai.ai_flags = AI_PASSIVE;
216     if (saddr->has_numeric && saddr->numeric) {
217         ai.ai_flags |= AI_NUMERICHOST | AI_NUMERICSERV;
218     }
219     ai.ai_family = inet_ai_family_from_address(saddr, &err);
220     ai.ai_socktype = SOCK_STREAM;
221 
222     if (err) {
223         error_propagate(errp, err);
224         return -1;
225     }
226 
227     if (saddr->host == NULL) {
228         error_setg(errp, "host not specified");
229         return -1;
230     }
231     if (saddr->port != NULL) {
232         pstrcpy(port, sizeof(port), saddr->port);
233     } else {
234         port[0] = '\0';
235     }
236 
237     /* lookup */
238     if (port_offset) {
239         unsigned long long baseport;
240         if (strlen(port) == 0) {
241             error_setg(errp, "port not specified");
242             return -1;
243         }
244         if (parse_uint_full(port, &baseport, 10) < 0) {
245             error_setg(errp, "can't convert to a number: %s", port);
246             return -1;
247         }
248         if (baseport > 65535 ||
249             baseport + port_offset > 65535) {
250             error_setg(errp, "port %s out of range", port);
251             return -1;
252         }
253         snprintf(port, sizeof(port), "%d", (int)baseport + port_offset);
254     }
255     rc = getaddrinfo(strlen(saddr->host) ? saddr->host : NULL,
256                      strlen(port) ? port : NULL, &ai, &res);
257     if (rc != 0) {
258         error_setg(errp, "address resolution failed for %s:%s: %s",
259                    saddr->host, port, gai_strerror(rc));
260         return -1;
261     }
262 
263     /* create socket + bind/listen */
264     for (e = res; e != NULL; e = e->ai_next) {
265         getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,
266 		        uaddr,INET6_ADDRSTRLEN,uport,32,
267 		        NI_NUMERICHOST | NI_NUMERICSERV);
268 
269         port_min = inet_getport(e);
270         port_max = saddr->has_to ? saddr->to + port_offset : port_min;
271         for (p = port_min; p <= port_max; p++) {
272             inet_setport(e, p);
273 
274             slisten = create_fast_reuse_socket(e);
275             if (slisten < 0) {
276                 /* First time we expect we might fail to create the socket
277                  * eg if 'e' has AF_INET6 but ipv6 kmod is not loaded.
278                  * Later iterations should always succeed if first iteration
279                  * worked though, so treat that as fatal.
280                  */
281                 if (p == port_min) {
282                     continue;
283                 } else {
284                     error_setg_errno(errp, errno,
285                                      "Failed to recreate failed listening socket");
286                     goto listen_failed;
287                 }
288             }
289             socket_created = true;
290 
291             rc = try_bind(slisten, saddr, e);
292             if (rc < 0) {
293                 if (errno != EADDRINUSE) {
294                     error_setg_errno(errp, errno, "Failed to bind socket");
295                     goto listen_failed;
296                 }
297             } else {
298                 if (!listen(slisten, 1)) {
299                     goto listen_ok;
300                 }
301                 if (errno != EADDRINUSE) {
302                     error_setg_errno(errp, errno, "Failed to listen on socket");
303                     goto listen_failed;
304                 }
305             }
306             /* Someone else managed to bind to the same port and beat us
307              * to listen on it! Socket semantics does not allow us to
308              * recover from this situation, so we need to recreate the
309              * socket to allow bind attempts for subsequent ports:
310              */
311             closesocket(slisten);
312             slisten = -1;
313         }
314     }
315     error_setg_errno(errp, errno,
316                      socket_created ?
317                      "Failed to find an available port" :
318                      "Failed to create a socket");
319 listen_failed:
320     saved_errno = errno;
321     if (slisten >= 0) {
322         closesocket(slisten);
323     }
324     freeaddrinfo(res);
325     errno = saved_errno;
326     return -1;
327 
328 listen_ok:
329     if (update_addr) {
330         g_free(saddr->host);
331         saddr->host = g_strdup(uaddr);
332         g_free(saddr->port);
333         saddr->port = g_strdup_printf("%d",
334                                       inet_getport(e) - port_offset);
335         saddr->has_ipv6 = saddr->ipv6 = e->ai_family == PF_INET6;
336         saddr->has_ipv4 = saddr->ipv4 = e->ai_family != PF_INET6;
337     }
338     freeaddrinfo(res);
339     return slisten;
340 }
341 
342 #ifdef _WIN32
343 #define QEMU_SOCKET_RC_INPROGRESS(rc) \
344     ((rc) == -EINPROGRESS || (rc) == -EWOULDBLOCK || (rc) == -WSAEALREADY)
345 #else
346 #define QEMU_SOCKET_RC_INPROGRESS(rc) \
347     ((rc) == -EINPROGRESS)
348 #endif
349 
350 static int inet_connect_addr(struct addrinfo *addr, Error **errp);
351 
352 static int inet_connect_addr(struct addrinfo *addr, Error **errp)
353 {
354     int sock, rc;
355 
356     sock = qemu_socket(addr->ai_family, addr->ai_socktype, addr->ai_protocol);
357     if (sock < 0) {
358         error_setg_errno(errp, errno, "Failed to create socket");
359         return -1;
360     }
361     socket_set_fast_reuse(sock);
362 
363     /* connect to peer */
364     do {
365         rc = 0;
366         if (connect(sock, addr->ai_addr, addr->ai_addrlen) < 0) {
367             rc = -errno;
368         }
369     } while (rc == -EINTR);
370 
371     if (rc < 0) {
372         error_setg_errno(errp, errno, "Failed to connect socket");
373         closesocket(sock);
374         return -1;
375     }
376 
377     return sock;
378 }
379 
380 static struct addrinfo *inet_parse_connect_saddr(InetSocketAddress *saddr,
381                                                  Error **errp)
382 {
383     struct addrinfo ai, *res;
384     int rc;
385     Error *err = NULL;
386     static int useV4Mapped = 1;
387 
388     memset(&ai, 0, sizeof(ai));
389 
390     ai.ai_flags = AI_CANONNAME | AI_ADDRCONFIG;
391     if (atomic_read(&useV4Mapped)) {
392         ai.ai_flags |= AI_V4MAPPED;
393     }
394     ai.ai_family = inet_ai_family_from_address(saddr, &err);
395     ai.ai_socktype = SOCK_STREAM;
396 
397     if (err) {
398         error_propagate(errp, err);
399         return NULL;
400     }
401 
402     if (saddr->host == NULL || saddr->port == NULL) {
403         error_setg(errp, "host and/or port not specified");
404         return NULL;
405     }
406 
407     /* lookup */
408     rc = getaddrinfo(saddr->host, saddr->port, &ai, &res);
409 
410     /* At least FreeBSD and OS-X 10.6 declare AI_V4MAPPED but
411      * then don't implement it in their getaddrinfo(). Detect
412      * this and retry without the flag since that's preferrable
413      * to a fatal error
414      */
415     if (rc == EAI_BADFLAGS &&
416         (ai.ai_flags & AI_V4MAPPED)) {
417         atomic_set(&useV4Mapped, 0);
418         ai.ai_flags &= ~AI_V4MAPPED;
419         rc = getaddrinfo(saddr->host, saddr->port, &ai, &res);
420     }
421     if (rc != 0) {
422         error_setg(errp, "address resolution failed for %s:%s: %s",
423                    saddr->host, saddr->port, gai_strerror(rc));
424         return NULL;
425     }
426     return res;
427 }
428 
429 /**
430  * Create a socket and connect it to an address.
431  *
432  * @saddr: Inet socket address specification
433  * @errp: set on error
434  *
435  * Returns: -1 on error, file descriptor on success.
436  */
437 int inet_connect_saddr(InetSocketAddress *saddr, Error **errp)
438 {
439     Error *local_err = NULL;
440     struct addrinfo *res, *e;
441     int sock = -1;
442 
443     res = inet_parse_connect_saddr(saddr, errp);
444     if (!res) {
445         return -1;
446     }
447 
448     for (e = res; e != NULL; e = e->ai_next) {
449         error_free(local_err);
450         local_err = NULL;
451         sock = inet_connect_addr(e, &local_err);
452         if (sock >= 0) {
453             break;
454         }
455     }
456 
457     if (sock < 0) {
458         error_propagate(errp, local_err);
459     }
460 
461     freeaddrinfo(res);
462     return sock;
463 }
464 
465 static int inet_dgram_saddr(InetSocketAddress *sraddr,
466                             InetSocketAddress *sladdr,
467                             Error **errp)
468 {
469     struct addrinfo ai, *peer = NULL, *local = NULL;
470     const char *addr;
471     const char *port;
472     int sock = -1, rc;
473     Error *err = NULL;
474 
475     /* lookup peer addr */
476     memset(&ai,0, sizeof(ai));
477     ai.ai_flags = AI_CANONNAME | AI_V4MAPPED | AI_ADDRCONFIG;
478     ai.ai_family = inet_ai_family_from_address(sraddr, &err);
479     ai.ai_socktype = SOCK_DGRAM;
480 
481     if (err) {
482         error_propagate(errp, err);
483         goto err;
484     }
485 
486     addr = sraddr->host;
487     port = sraddr->port;
488     if (addr == NULL || strlen(addr) == 0) {
489         addr = "localhost";
490     }
491     if (port == NULL || strlen(port) == 0) {
492         error_setg(errp, "remote port not specified");
493         goto err;
494     }
495 
496     if ((rc = getaddrinfo(addr, port, &ai, &peer)) != 0) {
497         error_setg(errp, "address resolution failed for %s:%s: %s", addr, port,
498                    gai_strerror(rc));
499         goto err;
500     }
501 
502     /* lookup local addr */
503     memset(&ai,0, sizeof(ai));
504     ai.ai_flags = AI_PASSIVE;
505     ai.ai_family = peer->ai_family;
506     ai.ai_socktype = SOCK_DGRAM;
507 
508     if (sladdr) {
509         addr = sladdr->host;
510         port = sladdr->port;
511         if (addr == NULL || strlen(addr) == 0) {
512             addr = NULL;
513         }
514         if (!port || strlen(port) == 0) {
515             port = "0";
516         }
517     } else {
518         addr = NULL;
519         port = "0";
520     }
521 
522     if ((rc = getaddrinfo(addr, port, &ai, &local)) != 0) {
523         error_setg(errp, "address resolution failed for %s:%s: %s", addr, port,
524                    gai_strerror(rc));
525         goto err;
526     }
527 
528     /* create socket */
529     sock = qemu_socket(peer->ai_family, peer->ai_socktype, peer->ai_protocol);
530     if (sock < 0) {
531         error_setg_errno(errp, errno, "Failed to create socket");
532         goto err;
533     }
534     socket_set_fast_reuse(sock);
535 
536     /* bind socket */
537     if (bind(sock, local->ai_addr, local->ai_addrlen) < 0) {
538         error_setg_errno(errp, errno, "Failed to bind socket");
539         goto err;
540     }
541 
542     /* connect to peer */
543     if (connect(sock,peer->ai_addr,peer->ai_addrlen) < 0) {
544         error_setg_errno(errp, errno, "Failed to connect socket");
545         goto err;
546     }
547 
548     freeaddrinfo(local);
549     freeaddrinfo(peer);
550     return sock;
551 
552 err:
553     if (sock != -1) {
554         closesocket(sock);
555     }
556     if (local) {
557         freeaddrinfo(local);
558     }
559     if (peer) {
560         freeaddrinfo(peer);
561     }
562 
563     return -1;
564 }
565 
566 /* compatibility wrapper */
567 int inet_parse(InetSocketAddress *addr, const char *str, Error **errp)
568 {
569     const char *optstr, *h;
570     char host[65];
571     char port[33];
572     int to;
573     int pos;
574 
575     memset(addr, 0, sizeof(*addr));
576 
577     /* parse address */
578     if (str[0] == ':') {
579         /* no host given */
580         host[0] = '\0';
581         if (sscanf(str, ":%32[^,]%n", port, &pos) != 1) {
582             error_setg(errp, "error parsing port in address '%s'", str);
583             return -1;
584         }
585     } else if (str[0] == '[') {
586         /* IPv6 addr */
587         if (sscanf(str, "[%64[^]]]:%32[^,]%n", host, port, &pos) != 2) {
588             error_setg(errp, "error parsing IPv6 address '%s'", str);
589             return -1;
590         }
591     } else {
592         /* hostname or IPv4 addr */
593         if (sscanf(str, "%64[^:]:%32[^,]%n", host, port, &pos) != 2) {
594             error_setg(errp, "error parsing address '%s'", str);
595             return -1;
596         }
597     }
598 
599     addr->host = g_strdup(host);
600     addr->port = g_strdup(port);
601 
602     /* parse options */
603     optstr = str + pos;
604     h = strstr(optstr, ",to=");
605     if (h) {
606         h += 4;
607         if (sscanf(h, "%d%n", &to, &pos) != 1 ||
608             (h[pos] != '\0' && h[pos] != ',')) {
609             error_setg(errp, "error parsing to= argument");
610             return -1;
611         }
612         addr->has_to = true;
613         addr->to = to;
614     }
615     if (strstr(optstr, ",ipv4")) {
616         addr->ipv4 = addr->has_ipv4 = true;
617     }
618     if (strstr(optstr, ",ipv6")) {
619         addr->ipv6 = addr->has_ipv6 = true;
620     }
621     return 0;
622 }
623 
624 
625 /**
626  * Create a blocking socket and connect it to an address.
627  *
628  * @str: address string
629  * @errp: set in case of an error
630  *
631  * Returns -1 in case of error, file descriptor on success
632  **/
633 int inet_connect(const char *str, Error **errp)
634 {
635     int sock = -1;
636     InetSocketAddress *addr = g_new(InetSocketAddress, 1);
637 
638     if (!inet_parse(addr, str, errp)) {
639         sock = inet_connect_saddr(addr, errp);
640     }
641     qapi_free_InetSocketAddress(addr);
642     return sock;
643 }
644 
645 #ifdef CONFIG_AF_VSOCK
646 static bool vsock_parse_vaddr_to_sockaddr(const VsockSocketAddress *vaddr,
647                                           struct sockaddr_vm *svm,
648                                           Error **errp)
649 {
650     unsigned long long val;
651 
652     memset(svm, 0, sizeof(*svm));
653     svm->svm_family = AF_VSOCK;
654 
655     if (parse_uint_full(vaddr->cid, &val, 10) < 0 ||
656         val > UINT32_MAX) {
657         error_setg(errp, "Failed to parse cid '%s'", vaddr->cid);
658         return false;
659     }
660     svm->svm_cid = val;
661 
662     if (parse_uint_full(vaddr->port, &val, 10) < 0 ||
663         val > UINT32_MAX) {
664         error_setg(errp, "Failed to parse port '%s'", vaddr->port);
665         return false;
666     }
667     svm->svm_port = val;
668 
669     return true;
670 }
671 
672 static int vsock_connect_addr(const struct sockaddr_vm *svm, Error **errp)
673 {
674     int sock, rc;
675 
676     sock = qemu_socket(AF_VSOCK, SOCK_STREAM, 0);
677     if (sock < 0) {
678         error_setg_errno(errp, errno, "Failed to create socket");
679         return -1;
680     }
681 
682     /* connect to peer */
683     do {
684         rc = 0;
685         if (connect(sock, (const struct sockaddr *)svm, sizeof(*svm)) < 0) {
686             rc = -errno;
687         }
688     } while (rc == -EINTR);
689 
690     if (rc < 0) {
691         error_setg_errno(errp, errno, "Failed to connect socket");
692         closesocket(sock);
693         return -1;
694     }
695 
696     return sock;
697 }
698 
699 static int vsock_connect_saddr(VsockSocketAddress *vaddr, Error **errp)
700 {
701     struct sockaddr_vm svm;
702     int sock = -1;
703 
704     if (!vsock_parse_vaddr_to_sockaddr(vaddr, &svm, errp)) {
705         return -1;
706     }
707 
708     sock = vsock_connect_addr(&svm, errp);
709 
710     return sock;
711 }
712 
713 static int vsock_listen_saddr(VsockSocketAddress *vaddr,
714                               Error **errp)
715 {
716     struct sockaddr_vm svm;
717     int slisten;
718 
719     if (!vsock_parse_vaddr_to_sockaddr(vaddr, &svm, errp)) {
720         return -1;
721     }
722 
723     slisten = qemu_socket(AF_VSOCK, SOCK_STREAM, 0);
724     if (slisten < 0) {
725         error_setg_errno(errp, errno, "Failed to create socket");
726         return -1;
727     }
728 
729     if (bind(slisten, (const struct sockaddr *)&svm, sizeof(svm)) != 0) {
730         error_setg_errno(errp, errno, "Failed to bind socket");
731         closesocket(slisten);
732         return -1;
733     }
734 
735     if (listen(slisten, 1) != 0) {
736         error_setg_errno(errp, errno, "Failed to listen on socket");
737         closesocket(slisten);
738         return -1;
739     }
740     return slisten;
741 }
742 
743 static int vsock_parse(VsockSocketAddress *addr, const char *str,
744                        Error **errp)
745 {
746     char cid[33];
747     char port[33];
748     int n;
749 
750     if (sscanf(str, "%32[^:]:%32[^,]%n", cid, port, &n) != 2) {
751         error_setg(errp, "error parsing address '%s'", str);
752         return -1;
753     }
754     if (str[n] != '\0') {
755         error_setg(errp, "trailing characters in address '%s'", str);
756         return -1;
757     }
758 
759     addr->cid = g_strdup(cid);
760     addr->port = g_strdup(port);
761     return 0;
762 }
763 #else
764 static void vsock_unsupported(Error **errp)
765 {
766     error_setg(errp, "socket family AF_VSOCK unsupported");
767 }
768 
769 static int vsock_connect_saddr(VsockSocketAddress *vaddr, Error **errp)
770 {
771     vsock_unsupported(errp);
772     return -1;
773 }
774 
775 static int vsock_listen_saddr(VsockSocketAddress *vaddr,
776                               Error **errp)
777 {
778     vsock_unsupported(errp);
779     return -1;
780 }
781 
782 static int vsock_parse(VsockSocketAddress *addr, const char *str,
783                         Error **errp)
784 {
785     vsock_unsupported(errp);
786     return -1;
787 }
788 #endif /* CONFIG_AF_VSOCK */
789 
790 #ifndef _WIN32
791 
792 static int unix_listen_saddr(UnixSocketAddress *saddr,
793                              bool update_addr,
794                              Error **errp)
795 {
796     struct sockaddr_un un;
797     int sock, fd;
798     char *pathbuf = NULL;
799     const char *path;
800 
801     sock = qemu_socket(PF_UNIX, SOCK_STREAM, 0);
802     if (sock < 0) {
803         error_setg_errno(errp, errno, "Failed to create Unix socket");
804         return -1;
805     }
806 
807     if (saddr->path && saddr->path[0]) {
808         path = saddr->path;
809     } else {
810         const char *tmpdir = getenv("TMPDIR");
811         tmpdir = tmpdir ? tmpdir : "/tmp";
812         path = pathbuf = g_strdup_printf("%s/qemu-socket-XXXXXX", tmpdir);
813     }
814 
815     if (strlen(path) > sizeof(un.sun_path)) {
816         error_setg(errp, "UNIX socket path '%s' is too long", path);
817         error_append_hint(errp, "Path must be less than %zu bytes\n",
818                           sizeof(un.sun_path));
819         goto err;
820     }
821 
822     if (pathbuf != NULL) {
823         /*
824          * This dummy fd usage silences the mktemp() unsecure warning.
825          * Using mkstemp() doesn't make things more secure here
826          * though.  bind() complains about existing files, so we have
827          * to unlink first and thus re-open the race window.  The
828          * worst case possible is bind() failing, i.e. a DoS attack.
829          */
830         fd = mkstemp(pathbuf);
831         if (fd < 0) {
832             error_setg_errno(errp, errno,
833                              "Failed to make a temporary socket %s", pathbuf);
834             goto err;
835         }
836         close(fd);
837     }
838 
839     if (unlink(path) < 0 && errno != ENOENT) {
840         error_setg_errno(errp, errno,
841                          "Failed to unlink socket %s", path);
842         goto err;
843     }
844 
845     memset(&un, 0, sizeof(un));
846     un.sun_family = AF_UNIX;
847     strncpy(un.sun_path, path, sizeof(un.sun_path));
848 
849     if (bind(sock, (struct sockaddr*) &un, sizeof(un)) < 0) {
850         error_setg_errno(errp, errno, "Failed to bind socket to %s", path);
851         goto err;
852     }
853     if (listen(sock, 1) < 0) {
854         error_setg_errno(errp, errno, "Failed to listen on socket");
855         goto err;
856     }
857 
858     if (update_addr && pathbuf) {
859         g_free(saddr->path);
860         saddr->path = pathbuf;
861     } else {
862         g_free(pathbuf);
863     }
864     return sock;
865 
866 err:
867     g_free(pathbuf);
868     closesocket(sock);
869     return -1;
870 }
871 
872 static int unix_connect_saddr(UnixSocketAddress *saddr, Error **errp)
873 {
874     struct sockaddr_un un;
875     int sock, rc;
876 
877     if (saddr->path == NULL) {
878         error_setg(errp, "unix connect: no path specified");
879         return -1;
880     }
881 
882     sock = qemu_socket(PF_UNIX, SOCK_STREAM, 0);
883     if (sock < 0) {
884         error_setg_errno(errp, errno, "Failed to create socket");
885         return -1;
886     }
887 
888     if (strlen(saddr->path) > sizeof(un.sun_path)) {
889         error_setg(errp, "UNIX socket path '%s' is too long", saddr->path);
890         error_append_hint(errp, "Path must be less than %zu bytes\n",
891                           sizeof(un.sun_path));
892         goto err;
893     }
894 
895     memset(&un, 0, sizeof(un));
896     un.sun_family = AF_UNIX;
897     strncpy(un.sun_path, saddr->path, sizeof(un.sun_path));
898 
899     /* connect to peer */
900     do {
901         rc = 0;
902         if (connect(sock, (struct sockaddr *) &un, sizeof(un)) < 0) {
903             rc = -errno;
904         }
905     } while (rc == -EINTR);
906 
907     if (rc < 0) {
908         error_setg_errno(errp, -rc, "Failed to connect socket %s",
909                          saddr->path);
910         goto err;
911     }
912 
913     return sock;
914 
915  err:
916     close(sock);
917     return -1;
918 }
919 
920 #else
921 
922 static int unix_listen_saddr(UnixSocketAddress *saddr,
923                              bool update_addr,
924                              Error **errp)
925 {
926     error_setg(errp, "unix sockets are not available on windows");
927     errno = ENOTSUP;
928     return -1;
929 }
930 
931 static int unix_connect_saddr(UnixSocketAddress *saddr, Error **errp)
932 {
933     error_setg(errp, "unix sockets are not available on windows");
934     errno = ENOTSUP;
935     return -1;
936 }
937 #endif
938 
939 /* compatibility wrapper */
940 int unix_listen(const char *str, char *ostr, int olen, Error **errp)
941 {
942     char *path, *optstr;
943     int sock, len;
944     UnixSocketAddress *saddr;
945 
946     saddr = g_new0(UnixSocketAddress, 1);
947 
948     optstr = strchr(str, ',');
949     if (optstr) {
950         len = optstr - str;
951         if (len) {
952             path = g_malloc(len+1);
953             snprintf(path, len+1, "%.*s", len, str);
954             saddr->path = path;
955         }
956     } else {
957         saddr->path = g_strdup(str);
958     }
959 
960     sock = unix_listen_saddr(saddr, true, errp);
961 
962     if (sock != -1 && ostr) {
963         snprintf(ostr, olen, "%s%s", saddr->path, optstr ? optstr : "");
964     }
965 
966     qapi_free_UnixSocketAddress(saddr);
967     return sock;
968 }
969 
970 int unix_connect(const char *path, Error **errp)
971 {
972     UnixSocketAddress *saddr;
973     int sock;
974 
975     saddr = g_new0(UnixSocketAddress, 1);
976     saddr->path = g_strdup(path);
977     sock = unix_connect_saddr(saddr, errp);
978     qapi_free_UnixSocketAddress(saddr);
979     return sock;
980 }
981 
982 
983 SocketAddress *socket_parse(const char *str, Error **errp)
984 {
985     SocketAddress *addr;
986 
987     addr = g_new0(SocketAddress, 1);
988     if (strstart(str, "unix:", NULL)) {
989         if (str[5] == '\0') {
990             error_setg(errp, "invalid Unix socket address");
991             goto fail;
992         } else {
993             addr->type = SOCKET_ADDRESS_TYPE_UNIX;
994             addr->u.q_unix.path = g_strdup(str + 5);
995         }
996     } else if (strstart(str, "fd:", NULL)) {
997         if (str[3] == '\0') {
998             error_setg(errp, "invalid file descriptor address");
999             goto fail;
1000         } else {
1001             addr->type = SOCKET_ADDRESS_TYPE_FD;
1002             addr->u.fd.str = g_strdup(str + 3);
1003         }
1004     } else if (strstart(str, "vsock:", NULL)) {
1005         addr->type = SOCKET_ADDRESS_TYPE_VSOCK;
1006         if (vsock_parse(&addr->u.vsock, str + strlen("vsock:"), errp)) {
1007             goto fail;
1008         }
1009     } else {
1010         addr->type = SOCKET_ADDRESS_TYPE_INET;
1011         if (inet_parse(&addr->u.inet, str, errp)) {
1012             goto fail;
1013         }
1014     }
1015     return addr;
1016 
1017 fail:
1018     qapi_free_SocketAddress(addr);
1019     return NULL;
1020 }
1021 
1022 int socket_connect(SocketAddress *addr, Error **errp)
1023 {
1024     int fd;
1025 
1026     switch (addr->type) {
1027     case SOCKET_ADDRESS_TYPE_INET:
1028         fd = inet_connect_saddr(&addr->u.inet, errp);
1029         break;
1030 
1031     case SOCKET_ADDRESS_TYPE_UNIX:
1032         fd = unix_connect_saddr(&addr->u.q_unix, errp);
1033         break;
1034 
1035     case SOCKET_ADDRESS_TYPE_FD:
1036         fd = monitor_get_fd(cur_mon, addr->u.fd.str, errp);
1037         break;
1038 
1039     case SOCKET_ADDRESS_TYPE_VSOCK:
1040         fd = vsock_connect_saddr(&addr->u.vsock, errp);
1041         break;
1042 
1043     default:
1044         abort();
1045     }
1046     return fd;
1047 }
1048 
1049 int socket_listen(SocketAddress *addr, Error **errp)
1050 {
1051     int fd;
1052 
1053     switch (addr->type) {
1054     case SOCKET_ADDRESS_TYPE_INET:
1055         fd = inet_listen_saddr(&addr->u.inet, 0, false, errp);
1056         break;
1057 
1058     case SOCKET_ADDRESS_TYPE_UNIX:
1059         fd = unix_listen_saddr(&addr->u.q_unix, false, errp);
1060         break;
1061 
1062     case SOCKET_ADDRESS_TYPE_FD:
1063         fd = monitor_get_fd(cur_mon, addr->u.fd.str, errp);
1064         break;
1065 
1066     case SOCKET_ADDRESS_TYPE_VSOCK:
1067         fd = vsock_listen_saddr(&addr->u.vsock, errp);
1068         break;
1069 
1070     default:
1071         abort();
1072     }
1073     return fd;
1074 }
1075 
1076 void socket_listen_cleanup(int fd, Error **errp)
1077 {
1078     SocketAddress *addr;
1079 
1080     addr = socket_local_address(fd, errp);
1081     if (!addr) {
1082         return;
1083     }
1084 
1085     if (addr->type == SOCKET_ADDRESS_TYPE_UNIX
1086         && addr->u.q_unix.path) {
1087         if (unlink(addr->u.q_unix.path) < 0 && errno != ENOENT) {
1088             error_setg_errno(errp, errno,
1089                              "Failed to unlink socket %s",
1090                              addr->u.q_unix.path);
1091         }
1092     }
1093 
1094     qapi_free_SocketAddress(addr);
1095 }
1096 
1097 int socket_dgram(SocketAddress *remote, SocketAddress *local, Error **errp)
1098 {
1099     int fd;
1100 
1101     /*
1102      * TODO SOCKET_ADDRESS_TYPE_FD when fd is AF_INET or AF_INET6
1103      * (although other address families can do SOCK_DGRAM, too)
1104      */
1105     switch (remote->type) {
1106     case SOCKET_ADDRESS_TYPE_INET:
1107         fd = inet_dgram_saddr(&remote->u.inet,
1108                               local ? &local->u.inet : NULL, errp);
1109         break;
1110 
1111     default:
1112         error_setg(errp, "socket type unsupported for datagram");
1113         fd = -1;
1114     }
1115     return fd;
1116 }
1117 
1118 
1119 static SocketAddress *
1120 socket_sockaddr_to_address_inet(struct sockaddr_storage *sa,
1121                                 socklen_t salen,
1122                                 Error **errp)
1123 {
1124     char host[NI_MAXHOST];
1125     char serv[NI_MAXSERV];
1126     SocketAddress *addr;
1127     InetSocketAddress *inet;
1128     int ret;
1129 
1130     ret = getnameinfo((struct sockaddr *)sa, salen,
1131                       host, sizeof(host),
1132                       serv, sizeof(serv),
1133                       NI_NUMERICHOST | NI_NUMERICSERV);
1134     if (ret != 0) {
1135         error_setg(errp, "Cannot format numeric socket address: %s",
1136                    gai_strerror(ret));
1137         return NULL;
1138     }
1139 
1140     addr = g_new0(SocketAddress, 1);
1141     addr->type = SOCKET_ADDRESS_TYPE_INET;
1142     inet = &addr->u.inet;
1143     inet->host = g_strdup(host);
1144     inet->port = g_strdup(serv);
1145     if (sa->ss_family == AF_INET) {
1146         inet->has_ipv4 = inet->ipv4 = true;
1147     } else {
1148         inet->has_ipv6 = inet->ipv6 = true;
1149     }
1150 
1151     return addr;
1152 }
1153 
1154 
1155 #ifndef WIN32
1156 static SocketAddress *
1157 socket_sockaddr_to_address_unix(struct sockaddr_storage *sa,
1158                                 socklen_t salen,
1159                                 Error **errp)
1160 {
1161     SocketAddress *addr;
1162     struct sockaddr_un *su = (struct sockaddr_un *)sa;
1163 
1164     addr = g_new0(SocketAddress, 1);
1165     addr->type = SOCKET_ADDRESS_TYPE_UNIX;
1166     if (su->sun_path[0]) {
1167         addr->u.q_unix.path = g_strndup(su->sun_path, sizeof(su->sun_path));
1168     }
1169 
1170     return addr;
1171 }
1172 #endif /* WIN32 */
1173 
1174 #ifdef CONFIG_AF_VSOCK
1175 static SocketAddress *
1176 socket_sockaddr_to_address_vsock(struct sockaddr_storage *sa,
1177                                  socklen_t salen,
1178                                  Error **errp)
1179 {
1180     SocketAddress *addr;
1181     VsockSocketAddress *vaddr;
1182     struct sockaddr_vm *svm = (struct sockaddr_vm *)sa;
1183 
1184     addr = g_new0(SocketAddress, 1);
1185     addr->type = SOCKET_ADDRESS_TYPE_VSOCK;
1186     vaddr = &addr->u.vsock;
1187     vaddr->cid = g_strdup_printf("%u", svm->svm_cid);
1188     vaddr->port = g_strdup_printf("%u", svm->svm_port);
1189 
1190     return addr;
1191 }
1192 #endif /* CONFIG_AF_VSOCK */
1193 
1194 SocketAddress *
1195 socket_sockaddr_to_address(struct sockaddr_storage *sa,
1196                            socklen_t salen,
1197                            Error **errp)
1198 {
1199     switch (sa->ss_family) {
1200     case AF_INET:
1201     case AF_INET6:
1202         return socket_sockaddr_to_address_inet(sa, salen, errp);
1203 
1204 #ifndef WIN32
1205     case AF_UNIX:
1206         return socket_sockaddr_to_address_unix(sa, salen, errp);
1207 #endif /* WIN32 */
1208 
1209 #ifdef CONFIG_AF_VSOCK
1210     case AF_VSOCK:
1211         return socket_sockaddr_to_address_vsock(sa, salen, errp);
1212 #endif
1213 
1214     default:
1215         error_setg(errp, "socket family %d unsupported",
1216                    sa->ss_family);
1217         return NULL;
1218     }
1219     return 0;
1220 }
1221 
1222 
1223 SocketAddress *socket_local_address(int fd, Error **errp)
1224 {
1225     struct sockaddr_storage ss;
1226     socklen_t sslen = sizeof(ss);
1227 
1228     if (getsockname(fd, (struct sockaddr *)&ss, &sslen) < 0) {
1229         error_setg_errno(errp, errno, "%s",
1230                          "Unable to query local socket address");
1231         return NULL;
1232     }
1233 
1234     return socket_sockaddr_to_address(&ss, sslen, errp);
1235 }
1236 
1237 
1238 SocketAddress *socket_remote_address(int fd, Error **errp)
1239 {
1240     struct sockaddr_storage ss;
1241     socklen_t sslen = sizeof(ss);
1242 
1243     if (getpeername(fd, (struct sockaddr *)&ss, &sslen) < 0) {
1244         error_setg_errno(errp, errno, "%s",
1245                          "Unable to query remote socket address");
1246         return NULL;
1247     }
1248 
1249     return socket_sockaddr_to_address(&ss, sslen, errp);
1250 }
1251 
1252 
1253 SocketAddress *socket_address_flatten(SocketAddressLegacy *addr_legacy)
1254 {
1255     SocketAddress *addr;
1256 
1257     if (!addr_legacy) {
1258         return NULL;
1259     }
1260 
1261     addr = g_new(SocketAddress, 1);
1262 
1263     switch (addr_legacy->type) {
1264     case SOCKET_ADDRESS_LEGACY_KIND_INET:
1265         addr->type = SOCKET_ADDRESS_TYPE_INET;
1266         QAPI_CLONE_MEMBERS(InetSocketAddress, &addr->u.inet,
1267                            addr_legacy->u.inet.data);
1268         break;
1269     case SOCKET_ADDRESS_LEGACY_KIND_UNIX:
1270         addr->type = SOCKET_ADDRESS_TYPE_UNIX;
1271         QAPI_CLONE_MEMBERS(UnixSocketAddress, &addr->u.q_unix,
1272                            addr_legacy->u.q_unix.data);
1273         break;
1274     case SOCKET_ADDRESS_LEGACY_KIND_VSOCK:
1275         addr->type = SOCKET_ADDRESS_TYPE_VSOCK;
1276         QAPI_CLONE_MEMBERS(VsockSocketAddress, &addr->u.vsock,
1277                            addr_legacy->u.vsock.data);
1278         break;
1279     case SOCKET_ADDRESS_LEGACY_KIND_FD:
1280         addr->type = SOCKET_ADDRESS_TYPE_FD;
1281         QAPI_CLONE_MEMBERS(String, &addr->u.fd, addr_legacy->u.fd.data);
1282         break;
1283     default:
1284         abort();
1285     }
1286 
1287     return addr;
1288 }
1289