xref: /qemu/util/qemu-sockets.c (revision fd38b162)
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 "qemu-common.h"
25 #include "monitor/monitor.h"
26 #include "qapi/clone-visitor.h"
27 #include "qapi/error.h"
28 #include "qapi/qapi-visit-sockets.h"
29 #include "qemu/sockets.h"
30 #include "qemu/main-loop.h"
31 #include "qapi/qobject-input-visitor.h"
32 #include "qapi/qobject-output-visitor.h"
33 #include "qemu/cutils.h"
34 
35 #ifndef AI_ADDRCONFIG
36 # define AI_ADDRCONFIG 0
37 #endif
38 
39 #ifndef AI_V4MAPPED
40 # define AI_V4MAPPED 0
41 #endif
42 
43 #ifndef AI_NUMERICSERV
44 # define AI_NUMERICSERV 0
45 #endif
46 
47 
48 static int inet_getport(struct addrinfo *e)
49 {
50     struct sockaddr_in *i4;
51     struct sockaddr_in6 *i6;
52 
53     switch (e->ai_family) {
54     case PF_INET6:
55         i6 = (void*)e->ai_addr;
56         return ntohs(i6->sin6_port);
57     case PF_INET:
58         i4 = (void*)e->ai_addr;
59         return ntohs(i4->sin_port);
60     default:
61         return 0;
62     }
63 }
64 
65 static void inet_setport(struct addrinfo *e, int port)
66 {
67     struct sockaddr_in *i4;
68     struct sockaddr_in6 *i6;
69 
70     switch (e->ai_family) {
71     case PF_INET6:
72         i6 = (void*)e->ai_addr;
73         i6->sin6_port = htons(port);
74         break;
75     case PF_INET:
76         i4 = (void*)e->ai_addr;
77         i4->sin_port = htons(port);
78         break;
79     }
80 }
81 
82 NetworkAddressFamily inet_netfamily(int family)
83 {
84     switch (family) {
85     case PF_INET6: return NETWORK_ADDRESS_FAMILY_IPV6;
86     case PF_INET:  return NETWORK_ADDRESS_FAMILY_IPV4;
87     case PF_UNIX:  return NETWORK_ADDRESS_FAMILY_UNIX;
88 #ifdef CONFIG_AF_VSOCK
89     case PF_VSOCK: return NETWORK_ADDRESS_FAMILY_VSOCK;
90 #endif /* CONFIG_AF_VSOCK */
91     }
92     return NETWORK_ADDRESS_FAMILY_UNKNOWN;
93 }
94 
95 bool fd_is_socket(int fd)
96 {
97     int optval;
98     socklen_t optlen = sizeof(optval);
99     return !qemu_getsockopt(fd, SOL_SOCKET, SO_TYPE, &optval, &optlen);
100 }
101 
102 
103 /*
104  * Matrix we're trying to apply
105  *
106  *  ipv4  ipv6   family
107  *   -     -       PF_UNSPEC
108  *   -     f       PF_INET
109  *   -     t       PF_INET6
110  *   f     -       PF_INET6
111  *   f     f       <error>
112  *   f     t       PF_INET6
113  *   t     -       PF_INET
114  *   t     f       PF_INET
115  *   t     t       PF_INET6/PF_UNSPEC
116  *
117  * NB, this matrix is only about getting the necessary results
118  * from getaddrinfo(). Some of the cases require further work
119  * after reading results from getaddrinfo in order to fully
120  * apply the logic the end user wants.
121  *
122  * In the first and last cases, we must set IPV6_V6ONLY=0
123  * when binding, to allow a single listener to potentially
124  * accept both IPv4+6 addresses.
125  */
126 int inet_ai_family_from_address(InetSocketAddress *addr,
127                                 Error **errp)
128 {
129     if (addr->has_ipv6 && addr->has_ipv4 &&
130         !addr->ipv6 && !addr->ipv4) {
131         error_setg(errp, "Cannot disable IPv4 and IPv6 at same time");
132         return PF_UNSPEC;
133     }
134     if ((addr->has_ipv6 && addr->ipv6) && (addr->has_ipv4 && addr->ipv4)) {
135         /*
136          * Some backends can only do a single listener. In that case
137          * we want empty hostname to resolve to "::" and then use the
138          * flag IPV6_V6ONLY==0 to get both protocols on 1 socket. This
139          * doesn't work for addresses other than "", so they're just
140          * inevitably broken until multiple listeners can be used,
141          * and thus we honour getaddrinfo automatic protocol detection
142          * Once all backends do multi-listener, remove the PF_INET6
143          * branch entirely.
144          */
145         if (!addr->host || g_str_equal(addr->host, "")) {
146             return PF_INET6;
147         } else {
148             return PF_UNSPEC;
149         }
150     }
151     if ((addr->has_ipv6 && addr->ipv6) || (addr->has_ipv4 && !addr->ipv4)) {
152         return PF_INET6;
153     }
154     if ((addr->has_ipv4 && addr->ipv4) || (addr->has_ipv6 && !addr->ipv6)) {
155         return PF_INET;
156     }
157     return PF_UNSPEC;
158 }
159 
160 static int create_fast_reuse_socket(struct addrinfo *e)
161 {
162     int slisten = qemu_socket(e->ai_family, e->ai_socktype, e->ai_protocol);
163     if (slisten < 0) {
164         return -1;
165     }
166     socket_set_fast_reuse(slisten);
167     return slisten;
168 }
169 
170 static int try_bind(int socket, InetSocketAddress *saddr, struct addrinfo *e)
171 {
172 #ifndef IPV6_V6ONLY
173     return bind(socket, e->ai_addr, e->ai_addrlen);
174 #else
175     /*
176      * Deals with first & last cases in matrix in comment
177      * for inet_ai_family_from_address().
178      */
179     int v6only =
180         ((!saddr->has_ipv4 && !saddr->has_ipv6) ||
181          (saddr->has_ipv4 && saddr->ipv4 &&
182           saddr->has_ipv6 && saddr->ipv6)) ? 0 : 1;
183     int stat;
184 
185  rebind:
186     if (e->ai_family == PF_INET6) {
187         qemu_setsockopt(socket, IPPROTO_IPV6, IPV6_V6ONLY, &v6only,
188                         sizeof(v6only));
189     }
190 
191     stat = bind(socket, e->ai_addr, e->ai_addrlen);
192     if (!stat) {
193         return 0;
194     }
195 
196     /* If we got EADDRINUSE from an IPv6 bind & v6only is unset,
197      * it could be that the IPv4 port is already claimed, so retry
198      * with v6only set
199      */
200     if (e->ai_family == PF_INET6 && errno == EADDRINUSE && !v6only) {
201         v6only = 1;
202         goto rebind;
203     }
204     return stat;
205 #endif
206 }
207 
208 static int inet_listen_saddr(InetSocketAddress *saddr,
209                              int port_offset,
210                              Error **errp)
211 {
212     struct addrinfo ai,*res,*e;
213     char port[33];
214     char uaddr[INET6_ADDRSTRLEN+1];
215     char uport[33];
216     int rc, port_min, port_max, p;
217     int slisten = -1;
218     int saved_errno = 0;
219     bool socket_created = false;
220     Error *err = NULL;
221 
222     if (saddr->keep_alive) {
223         error_setg(errp, "keep-alive option is not supported for passive "
224                    "sockets");
225         return -1;
226     }
227 
228     memset(&ai,0, sizeof(ai));
229     ai.ai_flags = AI_PASSIVE;
230     if (saddr->has_numeric && saddr->numeric) {
231         ai.ai_flags |= AI_NUMERICHOST | AI_NUMERICSERV;
232     }
233     ai.ai_family = inet_ai_family_from_address(saddr, &err);
234     ai.ai_socktype = SOCK_STREAM;
235 
236     if (err) {
237         error_propagate(errp, err);
238         return -1;
239     }
240 
241     if (saddr->host == NULL) {
242         error_setg(errp, "host not specified");
243         return -1;
244     }
245     if (saddr->port != NULL) {
246         pstrcpy(port, sizeof(port), saddr->port);
247     } else {
248         port[0] = '\0';
249     }
250 
251     /* lookup */
252     if (port_offset) {
253         unsigned long long baseport;
254         if (strlen(port) == 0) {
255             error_setg(errp, "port not specified");
256             return -1;
257         }
258         if (parse_uint_full(port, &baseport, 10) < 0) {
259             error_setg(errp, "can't convert to a number: %s", port);
260             return -1;
261         }
262         if (baseport > 65535 ||
263             baseport + port_offset > 65535) {
264             error_setg(errp, "port %s out of range", port);
265             return -1;
266         }
267         snprintf(port, sizeof(port), "%d", (int)baseport + port_offset);
268     }
269     rc = getaddrinfo(strlen(saddr->host) ? saddr->host : NULL,
270                      strlen(port) ? port : NULL, &ai, &res);
271     if (rc != 0) {
272         error_setg(errp, "address resolution failed for %s:%s: %s",
273                    saddr->host, port, gai_strerror(rc));
274         return -1;
275     }
276 
277     /* create socket + bind/listen */
278     for (e = res; e != NULL; e = e->ai_next) {
279         getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,
280                         uaddr,INET6_ADDRSTRLEN,uport,32,
281                         NI_NUMERICHOST | NI_NUMERICSERV);
282 
283         port_min = inet_getport(e);
284         port_max = saddr->has_to ? saddr->to + port_offset : port_min;
285         for (p = port_min; p <= port_max; p++) {
286             inet_setport(e, p);
287 
288             slisten = create_fast_reuse_socket(e);
289             if (slisten < 0) {
290                 /* First time we expect we might fail to create the socket
291                  * eg if 'e' has AF_INET6 but ipv6 kmod is not loaded.
292                  * Later iterations should always succeed if first iteration
293                  * worked though, so treat that as fatal.
294                  */
295                 if (p == port_min) {
296                     continue;
297                 } else {
298                     error_setg_errno(errp, errno,
299                                      "Failed to recreate failed listening socket");
300                     goto listen_failed;
301                 }
302             }
303             socket_created = true;
304 
305             rc = try_bind(slisten, saddr, e);
306             if (rc < 0) {
307                 if (errno != EADDRINUSE) {
308                     error_setg_errno(errp, errno, "Failed to bind socket");
309                     goto listen_failed;
310                 }
311             } else {
312                 if (!listen(slisten, 1)) {
313                     goto listen_ok;
314                 }
315                 if (errno != EADDRINUSE) {
316                     error_setg_errno(errp, errno, "Failed to listen on socket");
317                     goto listen_failed;
318                 }
319             }
320             /* Someone else managed to bind to the same port and beat us
321              * to listen on it! Socket semantics does not allow us to
322              * recover from this situation, so we need to recreate the
323              * socket to allow bind attempts for subsequent ports:
324              */
325             closesocket(slisten);
326             slisten = -1;
327         }
328     }
329     error_setg_errno(errp, errno,
330                      socket_created ?
331                      "Failed to find an available port" :
332                      "Failed to create a socket");
333 listen_failed:
334     saved_errno = errno;
335     if (slisten >= 0) {
336         closesocket(slisten);
337     }
338     freeaddrinfo(res);
339     errno = saved_errno;
340     return -1;
341 
342 listen_ok:
343     freeaddrinfo(res);
344     return slisten;
345 }
346 
347 #ifdef _WIN32
348 #define QEMU_SOCKET_RC_INPROGRESS(rc) \
349     ((rc) == -EINPROGRESS || (rc) == -EWOULDBLOCK || (rc) == -WSAEALREADY)
350 #else
351 #define QEMU_SOCKET_RC_INPROGRESS(rc) \
352     ((rc) == -EINPROGRESS)
353 #endif
354 
355 static int inet_connect_addr(struct addrinfo *addr, Error **errp);
356 
357 static int inet_connect_addr(struct addrinfo *addr, Error **errp)
358 {
359     int sock, rc;
360 
361     sock = qemu_socket(addr->ai_family, addr->ai_socktype, addr->ai_protocol);
362     if (sock < 0) {
363         error_setg_errno(errp, errno, "Failed to create socket");
364         return -1;
365     }
366     socket_set_fast_reuse(sock);
367 
368     /* connect to peer */
369     do {
370         rc = 0;
371         if (connect(sock, addr->ai_addr, addr->ai_addrlen) < 0) {
372             rc = -errno;
373         }
374     } while (rc == -EINTR);
375 
376     if (rc < 0) {
377         error_setg_errno(errp, errno, "Failed to connect socket");
378         closesocket(sock);
379         return -1;
380     }
381 
382     return sock;
383 }
384 
385 static struct addrinfo *inet_parse_connect_saddr(InetSocketAddress *saddr,
386                                                  Error **errp)
387 {
388     struct addrinfo ai, *res;
389     int rc;
390     Error *err = NULL;
391     static int useV4Mapped = 1;
392 
393     memset(&ai, 0, sizeof(ai));
394 
395     ai.ai_flags = AI_CANONNAME | AI_ADDRCONFIG;
396     if (atomic_read(&useV4Mapped)) {
397         ai.ai_flags |= AI_V4MAPPED;
398     }
399     ai.ai_family = inet_ai_family_from_address(saddr, &err);
400     ai.ai_socktype = SOCK_STREAM;
401 
402     if (err) {
403         error_propagate(errp, err);
404         return NULL;
405     }
406 
407     if (saddr->host == NULL || saddr->port == NULL) {
408         error_setg(errp, "host and/or port not specified");
409         return NULL;
410     }
411 
412     /* lookup */
413     rc = getaddrinfo(saddr->host, saddr->port, &ai, &res);
414 
415     /* At least FreeBSD and OS-X 10.6 declare AI_V4MAPPED but
416      * then don't implement it in their getaddrinfo(). Detect
417      * this and retry without the flag since that's preferrable
418      * to a fatal error
419      */
420     if (rc == EAI_BADFLAGS &&
421         (ai.ai_flags & AI_V4MAPPED)) {
422         atomic_set(&useV4Mapped, 0);
423         ai.ai_flags &= ~AI_V4MAPPED;
424         rc = getaddrinfo(saddr->host, saddr->port, &ai, &res);
425     }
426     if (rc != 0) {
427         error_setg(errp, "address resolution failed for %s:%s: %s",
428                    saddr->host, saddr->port, gai_strerror(rc));
429         return NULL;
430     }
431     return res;
432 }
433 
434 /**
435  * Create a socket and connect it to an address.
436  *
437  * @saddr: Inet socket address specification
438  * @errp: set on error
439  *
440  * Returns: -1 on error, file descriptor on success.
441  */
442 int inet_connect_saddr(InetSocketAddress *saddr, Error **errp)
443 {
444     Error *local_err = NULL;
445     struct addrinfo *res, *e;
446     int sock = -1;
447 
448     res = inet_parse_connect_saddr(saddr, errp);
449     if (!res) {
450         return -1;
451     }
452 
453     for (e = res; e != NULL; e = e->ai_next) {
454         error_free(local_err);
455         local_err = NULL;
456         sock = inet_connect_addr(e, &local_err);
457         if (sock >= 0) {
458             break;
459         }
460     }
461 
462     if (sock < 0) {
463         error_propagate(errp, local_err);
464     }
465 
466     freeaddrinfo(res);
467 
468     if (saddr->keep_alive) {
469         int val = 1;
470         int ret = qemu_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
471                                   &val, sizeof(val));
472 
473         if (ret < 0) {
474             error_setg_errno(errp, errno, "Unable to set KEEPALIVE");
475             close(sock);
476             return -1;
477         }
478     }
479 
480     return sock;
481 }
482 
483 static int inet_dgram_saddr(InetSocketAddress *sraddr,
484                             InetSocketAddress *sladdr,
485                             Error **errp)
486 {
487     struct addrinfo ai, *peer = NULL, *local = NULL;
488     const char *addr;
489     const char *port;
490     int sock = -1, rc;
491     Error *err = NULL;
492 
493     /* lookup peer addr */
494     memset(&ai,0, sizeof(ai));
495     ai.ai_flags = AI_CANONNAME | AI_V4MAPPED | AI_ADDRCONFIG;
496     ai.ai_family = inet_ai_family_from_address(sraddr, &err);
497     ai.ai_socktype = SOCK_DGRAM;
498 
499     if (err) {
500         error_propagate(errp, err);
501         goto err;
502     }
503 
504     addr = sraddr->host;
505     port = sraddr->port;
506     if (addr == NULL || strlen(addr) == 0) {
507         addr = "localhost";
508     }
509     if (port == NULL || strlen(port) == 0) {
510         error_setg(errp, "remote port not specified");
511         goto err;
512     }
513 
514     if ((rc = getaddrinfo(addr, port, &ai, &peer)) != 0) {
515         error_setg(errp, "address resolution failed for %s:%s: %s", addr, port,
516                    gai_strerror(rc));
517         goto err;
518     }
519 
520     /* lookup local addr */
521     memset(&ai,0, sizeof(ai));
522     ai.ai_flags = AI_PASSIVE;
523     ai.ai_family = peer->ai_family;
524     ai.ai_socktype = SOCK_DGRAM;
525 
526     if (sladdr) {
527         addr = sladdr->host;
528         port = sladdr->port;
529         if (addr == NULL || strlen(addr) == 0) {
530             addr = NULL;
531         }
532         if (!port || strlen(port) == 0) {
533             port = "0";
534         }
535     } else {
536         addr = NULL;
537         port = "0";
538     }
539 
540     if ((rc = getaddrinfo(addr, port, &ai, &local)) != 0) {
541         error_setg(errp, "address resolution failed for %s:%s: %s", addr, port,
542                    gai_strerror(rc));
543         goto err;
544     }
545 
546     /* create socket */
547     sock = qemu_socket(peer->ai_family, peer->ai_socktype, peer->ai_protocol);
548     if (sock < 0) {
549         error_setg_errno(errp, errno, "Failed to create socket");
550         goto err;
551     }
552     socket_set_fast_reuse(sock);
553 
554     /* bind socket */
555     if (bind(sock, local->ai_addr, local->ai_addrlen) < 0) {
556         error_setg_errno(errp, errno, "Failed to bind socket");
557         goto err;
558     }
559 
560     /* connect to peer */
561     if (connect(sock,peer->ai_addr,peer->ai_addrlen) < 0) {
562         error_setg_errno(errp, errno, "Failed to connect socket");
563         goto err;
564     }
565 
566     freeaddrinfo(local);
567     freeaddrinfo(peer);
568     return sock;
569 
570 err:
571     if (sock != -1) {
572         closesocket(sock);
573     }
574     if (local) {
575         freeaddrinfo(local);
576     }
577     if (peer) {
578         freeaddrinfo(peer);
579     }
580 
581     return -1;
582 }
583 
584 /* compatibility wrapper */
585 static int inet_parse_flag(const char *flagname, const char *optstr, bool *val,
586                            Error **errp)
587 {
588     char *end;
589     size_t len;
590 
591     end = strstr(optstr, ",");
592     if (end) {
593         if (end[1] == ',') { /* Reject 'ipv6=on,,foo' */
594             error_setg(errp, "error parsing '%s' flag '%s'", flagname, optstr);
595             return -1;
596         }
597         len = end - optstr;
598     } else {
599         len = strlen(optstr);
600     }
601     if (len == 0 || (len == 3 && strncmp(optstr, "=on", len) == 0)) {
602         *val = true;
603     } else if (len == 4 && strncmp(optstr, "=off", len) == 0) {
604         *val = false;
605     } else {
606         error_setg(errp, "error parsing '%s' flag '%s'", flagname, optstr);
607         return -1;
608     }
609     return 0;
610 }
611 
612 int inet_parse(InetSocketAddress *addr, const char *str, Error **errp)
613 {
614     const char *optstr, *h;
615     char host[65];
616     char port[33];
617     int to;
618     int pos;
619     char *begin;
620 
621     memset(addr, 0, sizeof(*addr));
622 
623     /* parse address */
624     if (str[0] == ':') {
625         /* no host given */
626         host[0] = '\0';
627         if (sscanf(str, ":%32[^,]%n", port, &pos) != 1) {
628             error_setg(errp, "error parsing port in address '%s'", str);
629             return -1;
630         }
631     } else if (str[0] == '[') {
632         /* IPv6 addr */
633         if (sscanf(str, "[%64[^]]]:%32[^,]%n", host, port, &pos) != 2) {
634             error_setg(errp, "error parsing IPv6 address '%s'", str);
635             return -1;
636         }
637     } else {
638         /* hostname or IPv4 addr */
639         if (sscanf(str, "%64[^:]:%32[^,]%n", host, port, &pos) != 2) {
640             error_setg(errp, "error parsing address '%s'", str);
641             return -1;
642         }
643     }
644 
645     addr->host = g_strdup(host);
646     addr->port = g_strdup(port);
647 
648     /* parse options */
649     optstr = str + pos;
650     h = strstr(optstr, ",to=");
651     if (h) {
652         h += 4;
653         if (sscanf(h, "%d%n", &to, &pos) != 1 ||
654             (h[pos] != '\0' && h[pos] != ',')) {
655             error_setg(errp, "error parsing to= argument");
656             return -1;
657         }
658         addr->has_to = true;
659         addr->to = to;
660     }
661     begin = strstr(optstr, ",ipv4");
662     if (begin) {
663         if (inet_parse_flag("ipv4", begin + 5, &addr->ipv4, errp) < 0) {
664             return -1;
665         }
666         addr->has_ipv4 = true;
667     }
668     begin = strstr(optstr, ",ipv6");
669     if (begin) {
670         if (inet_parse_flag("ipv6", begin + 5, &addr->ipv6, errp) < 0) {
671             return -1;
672         }
673         addr->has_ipv6 = true;
674     }
675     begin = strstr(optstr, ",keep-alive");
676     if (begin) {
677         if (inet_parse_flag("keep-alive", begin + strlen(",keep-alive"),
678                             &addr->keep_alive, errp) < 0)
679         {
680             return -1;
681         }
682         addr->has_keep_alive = true;
683     }
684     return 0;
685 }
686 
687 
688 /**
689  * Create a blocking socket and connect it to an address.
690  *
691  * @str: address string
692  * @errp: set in case of an error
693  *
694  * Returns -1 in case of error, file descriptor on success
695  **/
696 int inet_connect(const char *str, Error **errp)
697 {
698     int sock = -1;
699     InetSocketAddress *addr = g_new(InetSocketAddress, 1);
700 
701     if (!inet_parse(addr, str, errp)) {
702         sock = inet_connect_saddr(addr, errp);
703     }
704     qapi_free_InetSocketAddress(addr);
705     return sock;
706 }
707 
708 #ifdef CONFIG_AF_VSOCK
709 static bool vsock_parse_vaddr_to_sockaddr(const VsockSocketAddress *vaddr,
710                                           struct sockaddr_vm *svm,
711                                           Error **errp)
712 {
713     unsigned long long val;
714 
715     memset(svm, 0, sizeof(*svm));
716     svm->svm_family = AF_VSOCK;
717 
718     if (parse_uint_full(vaddr->cid, &val, 10) < 0 ||
719         val > UINT32_MAX) {
720         error_setg(errp, "Failed to parse cid '%s'", vaddr->cid);
721         return false;
722     }
723     svm->svm_cid = val;
724 
725     if (parse_uint_full(vaddr->port, &val, 10) < 0 ||
726         val > UINT32_MAX) {
727         error_setg(errp, "Failed to parse port '%s'", vaddr->port);
728         return false;
729     }
730     svm->svm_port = val;
731 
732     return true;
733 }
734 
735 static int vsock_connect_addr(const struct sockaddr_vm *svm, Error **errp)
736 {
737     int sock, rc;
738 
739     sock = qemu_socket(AF_VSOCK, SOCK_STREAM, 0);
740     if (sock < 0) {
741         error_setg_errno(errp, errno, "Failed to create socket");
742         return -1;
743     }
744 
745     /* connect to peer */
746     do {
747         rc = 0;
748         if (connect(sock, (const struct sockaddr *)svm, sizeof(*svm)) < 0) {
749             rc = -errno;
750         }
751     } while (rc == -EINTR);
752 
753     if (rc < 0) {
754         error_setg_errno(errp, errno, "Failed to connect socket");
755         closesocket(sock);
756         return -1;
757     }
758 
759     return sock;
760 }
761 
762 static int vsock_connect_saddr(VsockSocketAddress *vaddr, Error **errp)
763 {
764     struct sockaddr_vm svm;
765     int sock = -1;
766 
767     if (!vsock_parse_vaddr_to_sockaddr(vaddr, &svm, errp)) {
768         return -1;
769     }
770 
771     sock = vsock_connect_addr(&svm, errp);
772 
773     return sock;
774 }
775 
776 static int vsock_listen_saddr(VsockSocketAddress *vaddr,
777                               Error **errp)
778 {
779     struct sockaddr_vm svm;
780     int slisten;
781 
782     if (!vsock_parse_vaddr_to_sockaddr(vaddr, &svm, errp)) {
783         return -1;
784     }
785 
786     slisten = qemu_socket(AF_VSOCK, SOCK_STREAM, 0);
787     if (slisten < 0) {
788         error_setg_errno(errp, errno, "Failed to create socket");
789         return -1;
790     }
791 
792     if (bind(slisten, (const struct sockaddr *)&svm, sizeof(svm)) != 0) {
793         error_setg_errno(errp, errno, "Failed to bind socket");
794         closesocket(slisten);
795         return -1;
796     }
797 
798     if (listen(slisten, 1) != 0) {
799         error_setg_errno(errp, errno, "Failed to listen on socket");
800         closesocket(slisten);
801         return -1;
802     }
803     return slisten;
804 }
805 
806 static int vsock_parse(VsockSocketAddress *addr, const char *str,
807                        Error **errp)
808 {
809     char cid[33];
810     char port[33];
811     int n;
812 
813     if (sscanf(str, "%32[^:]:%32[^,]%n", cid, port, &n) != 2) {
814         error_setg(errp, "error parsing address '%s'", str);
815         return -1;
816     }
817     if (str[n] != '\0') {
818         error_setg(errp, "trailing characters in address '%s'", str);
819         return -1;
820     }
821 
822     addr->cid = g_strdup(cid);
823     addr->port = g_strdup(port);
824     return 0;
825 }
826 #else
827 static void vsock_unsupported(Error **errp)
828 {
829     error_setg(errp, "socket family AF_VSOCK unsupported");
830 }
831 
832 static int vsock_connect_saddr(VsockSocketAddress *vaddr, Error **errp)
833 {
834     vsock_unsupported(errp);
835     return -1;
836 }
837 
838 static int vsock_listen_saddr(VsockSocketAddress *vaddr,
839                               Error **errp)
840 {
841     vsock_unsupported(errp);
842     return -1;
843 }
844 
845 static int vsock_parse(VsockSocketAddress *addr, const char *str,
846                         Error **errp)
847 {
848     vsock_unsupported(errp);
849     return -1;
850 }
851 #endif /* CONFIG_AF_VSOCK */
852 
853 #ifndef _WIN32
854 
855 static int unix_listen_saddr(UnixSocketAddress *saddr,
856                              Error **errp)
857 {
858     struct sockaddr_un un;
859     int sock, fd;
860     char *pathbuf = NULL;
861     const char *path;
862     size_t pathlen;
863 
864     sock = qemu_socket(PF_UNIX, SOCK_STREAM, 0);
865     if (sock < 0) {
866         error_setg_errno(errp, errno, "Failed to create Unix socket");
867         return -1;
868     }
869 
870     if (saddr->path && saddr->path[0]) {
871         path = saddr->path;
872     } else {
873         const char *tmpdir = getenv("TMPDIR");
874         tmpdir = tmpdir ? tmpdir : "/tmp";
875         path = pathbuf = g_strdup_printf("%s/qemu-socket-XXXXXX", tmpdir);
876     }
877 
878     pathlen = strlen(path);
879     if (pathlen > sizeof(un.sun_path)) {
880         error_setg(errp, "UNIX socket path '%s' is too long", path);
881         error_append_hint(errp, "Path must be less than %zu bytes\n",
882                           sizeof(un.sun_path));
883         goto err;
884     }
885 
886     if (pathbuf != NULL) {
887         /*
888          * This dummy fd usage silences the mktemp() unsecure warning.
889          * Using mkstemp() doesn't make things more secure here
890          * though.  bind() complains about existing files, so we have
891          * to unlink first and thus re-open the race window.  The
892          * worst case possible is bind() failing, i.e. a DoS attack.
893          */
894         fd = mkstemp(pathbuf);
895         if (fd < 0) {
896             error_setg_errno(errp, errno,
897                              "Failed to make a temporary socket %s", pathbuf);
898             goto err;
899         }
900         close(fd);
901     }
902 
903     if (unlink(path) < 0 && errno != ENOENT) {
904         error_setg_errno(errp, errno,
905                          "Failed to unlink socket %s", path);
906         goto err;
907     }
908 
909     memset(&un, 0, sizeof(un));
910     un.sun_family = AF_UNIX;
911     memcpy(un.sun_path, path, pathlen);
912 
913     if (bind(sock, (struct sockaddr*) &un, sizeof(un)) < 0) {
914         error_setg_errno(errp, errno, "Failed to bind socket to %s", path);
915         goto err;
916     }
917     if (listen(sock, 1) < 0) {
918         error_setg_errno(errp, errno, "Failed to listen on socket");
919         goto err;
920     }
921 
922     g_free(pathbuf);
923     return sock;
924 
925 err:
926     g_free(pathbuf);
927     closesocket(sock);
928     return -1;
929 }
930 
931 static int unix_connect_saddr(UnixSocketAddress *saddr, Error **errp)
932 {
933     struct sockaddr_un un;
934     int sock, rc;
935     size_t pathlen;
936 
937     if (saddr->path == NULL) {
938         error_setg(errp, "unix connect: no path specified");
939         return -1;
940     }
941 
942     sock = qemu_socket(PF_UNIX, SOCK_STREAM, 0);
943     if (sock < 0) {
944         error_setg_errno(errp, errno, "Failed to create socket");
945         return -1;
946     }
947 
948     pathlen = strlen(saddr->path);
949     if (pathlen > sizeof(un.sun_path)) {
950         error_setg(errp, "UNIX socket path '%s' is too long", saddr->path);
951         error_append_hint(errp, "Path must be less than %zu bytes\n",
952                           sizeof(un.sun_path));
953         goto err;
954     }
955 
956     memset(&un, 0, sizeof(un));
957     un.sun_family = AF_UNIX;
958     memcpy(un.sun_path, saddr->path, pathlen);
959 
960     /* connect to peer */
961     do {
962         rc = 0;
963         if (connect(sock, (struct sockaddr *) &un, sizeof(un)) < 0) {
964             rc = -errno;
965         }
966     } while (rc == -EINTR);
967 
968     if (rc < 0) {
969         error_setg_errno(errp, -rc, "Failed to connect socket %s",
970                          saddr->path);
971         goto err;
972     }
973 
974     return sock;
975 
976  err:
977     close(sock);
978     return -1;
979 }
980 
981 #else
982 
983 static int unix_listen_saddr(UnixSocketAddress *saddr,
984                              Error **errp)
985 {
986     error_setg(errp, "unix sockets are not available on windows");
987     errno = ENOTSUP;
988     return -1;
989 }
990 
991 static int unix_connect_saddr(UnixSocketAddress *saddr, Error **errp)
992 {
993     error_setg(errp, "unix sockets are not available on windows");
994     errno = ENOTSUP;
995     return -1;
996 }
997 #endif
998 
999 /* compatibility wrapper */
1000 int unix_listen(const char *str, Error **errp)
1001 {
1002     UnixSocketAddress *saddr;
1003     int sock;
1004 
1005     saddr = g_new0(UnixSocketAddress, 1);
1006     saddr->path = g_strdup(str);
1007     sock = unix_listen_saddr(saddr, errp);
1008     qapi_free_UnixSocketAddress(saddr);
1009     return sock;
1010 }
1011 
1012 int unix_connect(const char *path, Error **errp)
1013 {
1014     UnixSocketAddress *saddr;
1015     int sock;
1016 
1017     saddr = g_new0(UnixSocketAddress, 1);
1018     saddr->path = g_strdup(path);
1019     sock = unix_connect_saddr(saddr, errp);
1020     qapi_free_UnixSocketAddress(saddr);
1021     return sock;
1022 }
1023 
1024 
1025 SocketAddress *socket_parse(const char *str, Error **errp)
1026 {
1027     SocketAddress *addr;
1028 
1029     addr = g_new0(SocketAddress, 1);
1030     if (strstart(str, "unix:", NULL)) {
1031         if (str[5] == '\0') {
1032             error_setg(errp, "invalid Unix socket address");
1033             goto fail;
1034         } else {
1035             addr->type = SOCKET_ADDRESS_TYPE_UNIX;
1036             addr->u.q_unix.path = g_strdup(str + 5);
1037         }
1038     } else if (strstart(str, "fd:", NULL)) {
1039         if (str[3] == '\0') {
1040             error_setg(errp, "invalid file descriptor address");
1041             goto fail;
1042         } else {
1043             addr->type = SOCKET_ADDRESS_TYPE_FD;
1044             addr->u.fd.str = g_strdup(str + 3);
1045         }
1046     } else if (strstart(str, "vsock:", NULL)) {
1047         addr->type = SOCKET_ADDRESS_TYPE_VSOCK;
1048         if (vsock_parse(&addr->u.vsock, str + strlen("vsock:"), errp)) {
1049             goto fail;
1050         }
1051     } else {
1052         addr->type = SOCKET_ADDRESS_TYPE_INET;
1053         if (inet_parse(&addr->u.inet, str, errp)) {
1054             goto fail;
1055         }
1056     }
1057     return addr;
1058 
1059 fail:
1060     qapi_free_SocketAddress(addr);
1061     return NULL;
1062 }
1063 
1064 static int socket_get_fd(const char *fdstr, Error **errp)
1065 {
1066     int fd;
1067     if (cur_mon) {
1068         fd = monitor_get_fd(cur_mon, fdstr, errp);
1069         if (fd < 0) {
1070             return -1;
1071         }
1072     } else {
1073         if (qemu_strtoi(fdstr, NULL, 10, &fd) < 0) {
1074             error_setg_errno(errp, errno,
1075                              "Unable to parse FD number %s",
1076                              fdstr);
1077             return -1;
1078         }
1079     }
1080     if (!fd_is_socket(fd)) {
1081         error_setg(errp, "File descriptor '%s' is not a socket", fdstr);
1082         close(fd);
1083         return -1;
1084     }
1085     return fd;
1086 }
1087 
1088 int socket_connect(SocketAddress *addr, Error **errp)
1089 {
1090     int fd;
1091 
1092     switch (addr->type) {
1093     case SOCKET_ADDRESS_TYPE_INET:
1094         fd = inet_connect_saddr(&addr->u.inet, errp);
1095         break;
1096 
1097     case SOCKET_ADDRESS_TYPE_UNIX:
1098         fd = unix_connect_saddr(&addr->u.q_unix, errp);
1099         break;
1100 
1101     case SOCKET_ADDRESS_TYPE_FD:
1102         fd = socket_get_fd(addr->u.fd.str, errp);
1103         break;
1104 
1105     case SOCKET_ADDRESS_TYPE_VSOCK:
1106         fd = vsock_connect_saddr(&addr->u.vsock, errp);
1107         break;
1108 
1109     default:
1110         abort();
1111     }
1112     return fd;
1113 }
1114 
1115 int socket_listen(SocketAddress *addr, Error **errp)
1116 {
1117     int fd;
1118 
1119     switch (addr->type) {
1120     case SOCKET_ADDRESS_TYPE_INET:
1121         fd = inet_listen_saddr(&addr->u.inet, 0, errp);
1122         break;
1123 
1124     case SOCKET_ADDRESS_TYPE_UNIX:
1125         fd = unix_listen_saddr(&addr->u.q_unix, errp);
1126         break;
1127 
1128     case SOCKET_ADDRESS_TYPE_FD:
1129         fd = socket_get_fd(addr->u.fd.str, errp);
1130         break;
1131 
1132     case SOCKET_ADDRESS_TYPE_VSOCK:
1133         fd = vsock_listen_saddr(&addr->u.vsock, errp);
1134         break;
1135 
1136     default:
1137         abort();
1138     }
1139     return fd;
1140 }
1141 
1142 void socket_listen_cleanup(int fd, Error **errp)
1143 {
1144     SocketAddress *addr;
1145 
1146     addr = socket_local_address(fd, errp);
1147     if (!addr) {
1148         return;
1149     }
1150 
1151     if (addr->type == SOCKET_ADDRESS_TYPE_UNIX
1152         && addr->u.q_unix.path) {
1153         if (unlink(addr->u.q_unix.path) < 0 && errno != ENOENT) {
1154             error_setg_errno(errp, errno,
1155                              "Failed to unlink socket %s",
1156                              addr->u.q_unix.path);
1157         }
1158     }
1159 
1160     qapi_free_SocketAddress(addr);
1161 }
1162 
1163 int socket_dgram(SocketAddress *remote, SocketAddress *local, Error **errp)
1164 {
1165     int fd;
1166 
1167     /*
1168      * TODO SOCKET_ADDRESS_TYPE_FD when fd is AF_INET or AF_INET6
1169      * (although other address families can do SOCK_DGRAM, too)
1170      */
1171     switch (remote->type) {
1172     case SOCKET_ADDRESS_TYPE_INET:
1173         fd = inet_dgram_saddr(&remote->u.inet,
1174                               local ? &local->u.inet : NULL, errp);
1175         break;
1176 
1177     default:
1178         error_setg(errp, "socket type unsupported for datagram");
1179         fd = -1;
1180     }
1181     return fd;
1182 }
1183 
1184 
1185 static SocketAddress *
1186 socket_sockaddr_to_address_inet(struct sockaddr_storage *sa,
1187                                 socklen_t salen,
1188                                 Error **errp)
1189 {
1190     char host[NI_MAXHOST];
1191     char serv[NI_MAXSERV];
1192     SocketAddress *addr;
1193     InetSocketAddress *inet;
1194     int ret;
1195 
1196     ret = getnameinfo((struct sockaddr *)sa, salen,
1197                       host, sizeof(host),
1198                       serv, sizeof(serv),
1199                       NI_NUMERICHOST | NI_NUMERICSERV);
1200     if (ret != 0) {
1201         error_setg(errp, "Cannot format numeric socket address: %s",
1202                    gai_strerror(ret));
1203         return NULL;
1204     }
1205 
1206     addr = g_new0(SocketAddress, 1);
1207     addr->type = SOCKET_ADDRESS_TYPE_INET;
1208     inet = &addr->u.inet;
1209     inet->host = g_strdup(host);
1210     inet->port = g_strdup(serv);
1211     if (sa->ss_family == AF_INET) {
1212         inet->has_ipv4 = inet->ipv4 = true;
1213     } else {
1214         inet->has_ipv6 = inet->ipv6 = true;
1215     }
1216 
1217     return addr;
1218 }
1219 
1220 
1221 #ifndef WIN32
1222 static SocketAddress *
1223 socket_sockaddr_to_address_unix(struct sockaddr_storage *sa,
1224                                 socklen_t salen,
1225                                 Error **errp)
1226 {
1227     SocketAddress *addr;
1228     struct sockaddr_un *su = (struct sockaddr_un *)sa;
1229 
1230     addr = g_new0(SocketAddress, 1);
1231     addr->type = SOCKET_ADDRESS_TYPE_UNIX;
1232     if (su->sun_path[0]) {
1233         addr->u.q_unix.path = g_strndup(su->sun_path, sizeof(su->sun_path));
1234     }
1235 
1236     return addr;
1237 }
1238 #endif /* WIN32 */
1239 
1240 #ifdef CONFIG_AF_VSOCK
1241 static SocketAddress *
1242 socket_sockaddr_to_address_vsock(struct sockaddr_storage *sa,
1243                                  socklen_t salen,
1244                                  Error **errp)
1245 {
1246     SocketAddress *addr;
1247     VsockSocketAddress *vaddr;
1248     struct sockaddr_vm *svm = (struct sockaddr_vm *)sa;
1249 
1250     addr = g_new0(SocketAddress, 1);
1251     addr->type = SOCKET_ADDRESS_TYPE_VSOCK;
1252     vaddr = &addr->u.vsock;
1253     vaddr->cid = g_strdup_printf("%u", svm->svm_cid);
1254     vaddr->port = g_strdup_printf("%u", svm->svm_port);
1255 
1256     return addr;
1257 }
1258 #endif /* CONFIG_AF_VSOCK */
1259 
1260 SocketAddress *
1261 socket_sockaddr_to_address(struct sockaddr_storage *sa,
1262                            socklen_t salen,
1263                            Error **errp)
1264 {
1265     switch (sa->ss_family) {
1266     case AF_INET:
1267     case AF_INET6:
1268         return socket_sockaddr_to_address_inet(sa, salen, errp);
1269 
1270 #ifndef WIN32
1271     case AF_UNIX:
1272         return socket_sockaddr_to_address_unix(sa, salen, errp);
1273 #endif /* WIN32 */
1274 
1275 #ifdef CONFIG_AF_VSOCK
1276     case AF_VSOCK:
1277         return socket_sockaddr_to_address_vsock(sa, salen, errp);
1278 #endif
1279 
1280     default:
1281         error_setg(errp, "socket family %d unsupported",
1282                    sa->ss_family);
1283         return NULL;
1284     }
1285     return 0;
1286 }
1287 
1288 
1289 SocketAddress *socket_local_address(int fd, Error **errp)
1290 {
1291     struct sockaddr_storage ss;
1292     socklen_t sslen = sizeof(ss);
1293 
1294     if (getsockname(fd, (struct sockaddr *)&ss, &sslen) < 0) {
1295         error_setg_errno(errp, errno, "%s",
1296                          "Unable to query local socket address");
1297         return NULL;
1298     }
1299 
1300     return socket_sockaddr_to_address(&ss, sslen, errp);
1301 }
1302 
1303 
1304 SocketAddress *socket_remote_address(int fd, Error **errp)
1305 {
1306     struct sockaddr_storage ss;
1307     socklen_t sslen = sizeof(ss);
1308 
1309     if (getpeername(fd, (struct sockaddr *)&ss, &sslen) < 0) {
1310         error_setg_errno(errp, errno, "%s",
1311                          "Unable to query remote socket address");
1312         return NULL;
1313     }
1314 
1315     return socket_sockaddr_to_address(&ss, sslen, errp);
1316 }
1317 
1318 
1319 SocketAddress *socket_address_flatten(SocketAddressLegacy *addr_legacy)
1320 {
1321     SocketAddress *addr;
1322 
1323     if (!addr_legacy) {
1324         return NULL;
1325     }
1326 
1327     addr = g_new(SocketAddress, 1);
1328 
1329     switch (addr_legacy->type) {
1330     case SOCKET_ADDRESS_LEGACY_KIND_INET:
1331         addr->type = SOCKET_ADDRESS_TYPE_INET;
1332         QAPI_CLONE_MEMBERS(InetSocketAddress, &addr->u.inet,
1333                            addr_legacy->u.inet.data);
1334         break;
1335     case SOCKET_ADDRESS_LEGACY_KIND_UNIX:
1336         addr->type = SOCKET_ADDRESS_TYPE_UNIX;
1337         QAPI_CLONE_MEMBERS(UnixSocketAddress, &addr->u.q_unix,
1338                            addr_legacy->u.q_unix.data);
1339         break;
1340     case SOCKET_ADDRESS_LEGACY_KIND_VSOCK:
1341         addr->type = SOCKET_ADDRESS_TYPE_VSOCK;
1342         QAPI_CLONE_MEMBERS(VsockSocketAddress, &addr->u.vsock,
1343                            addr_legacy->u.vsock.data);
1344         break;
1345     case SOCKET_ADDRESS_LEGACY_KIND_FD:
1346         addr->type = SOCKET_ADDRESS_TYPE_FD;
1347         QAPI_CLONE_MEMBERS(String, &addr->u.fd, addr_legacy->u.fd.data);
1348         break;
1349     default:
1350         abort();
1351     }
1352 
1353     return addr;
1354 }
1355