xref: /openbmc/qemu/util/qemu-sockets.c (revision 0b84b662)
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 #include "trace.h"
35 
36 #ifndef AI_ADDRCONFIG
37 # define AI_ADDRCONFIG 0
38 #endif
39 
40 #ifndef AI_V4MAPPED
41 # define AI_V4MAPPED 0
42 #endif
43 
44 #ifndef AI_NUMERICSERV
45 # define AI_NUMERICSERV 0
46 #endif
47 
48 
49 static int inet_getport(struct addrinfo *e)
50 {
51     struct sockaddr_in *i4;
52     struct sockaddr_in6 *i6;
53 
54     switch (e->ai_family) {
55     case PF_INET6:
56         i6 = (void*)e->ai_addr;
57         return ntohs(i6->sin6_port);
58     case PF_INET:
59         i4 = (void*)e->ai_addr;
60         return ntohs(i4->sin_port);
61     default:
62         return 0;
63     }
64 }
65 
66 static void inet_setport(struct addrinfo *e, int port)
67 {
68     struct sockaddr_in *i4;
69     struct sockaddr_in6 *i6;
70 
71     switch (e->ai_family) {
72     case PF_INET6:
73         i6 = (void*)e->ai_addr;
74         i6->sin6_port = htons(port);
75         break;
76     case PF_INET:
77         i4 = (void*)e->ai_addr;
78         i4->sin_port = htons(port);
79         break;
80     }
81 }
82 
83 NetworkAddressFamily inet_netfamily(int family)
84 {
85     switch (family) {
86     case PF_INET6: return NETWORK_ADDRESS_FAMILY_IPV6;
87     case PF_INET:  return NETWORK_ADDRESS_FAMILY_IPV4;
88     case PF_UNIX:  return NETWORK_ADDRESS_FAMILY_UNIX;
89 #ifdef CONFIG_AF_VSOCK
90     case PF_VSOCK: return NETWORK_ADDRESS_FAMILY_VSOCK;
91 #endif /* CONFIG_AF_VSOCK */
92     }
93     return NETWORK_ADDRESS_FAMILY_UNKNOWN;
94 }
95 
96 bool fd_is_socket(int fd)
97 {
98     int optval;
99     socklen_t optlen = sizeof(optval);
100     return !qemu_getsockopt(fd, SOL_SOCKET, SO_TYPE, &optval, &optlen);
101 }
102 
103 
104 /*
105  * Matrix we're trying to apply
106  *
107  *  ipv4  ipv6   family
108  *   -     -       PF_UNSPEC
109  *   -     f       PF_INET
110  *   -     t       PF_INET6
111  *   f     -       PF_INET6
112  *   f     f       <error>
113  *   f     t       PF_INET6
114  *   t     -       PF_INET
115  *   t     f       PF_INET
116  *   t     t       PF_INET6/PF_UNSPEC
117  *
118  * NB, this matrix is only about getting the necessary results
119  * from getaddrinfo(). Some of the cases require further work
120  * after reading results from getaddrinfo in order to fully
121  * apply the logic the end user wants.
122  *
123  * In the first and last cases, we must set IPV6_V6ONLY=0
124  * when binding, to allow a single listener to potentially
125  * accept both IPv4+6 addresses.
126  */
127 int inet_ai_family_from_address(InetSocketAddress *addr,
128                                 Error **errp)
129 {
130     if (addr->has_ipv6 && addr->has_ipv4 &&
131         !addr->ipv6 && !addr->ipv4) {
132         error_setg(errp, "Cannot disable IPv4 and IPv6 at same time");
133         return PF_UNSPEC;
134     }
135     if ((addr->has_ipv6 && addr->ipv6) && (addr->has_ipv4 && addr->ipv4)) {
136         /*
137          * Some backends can only do a single listener. In that case
138          * we want empty hostname to resolve to "::" and then use the
139          * flag IPV6_V6ONLY==0 to get both protocols on 1 socket. This
140          * doesn't work for addresses other than "", so they're just
141          * inevitably broken until multiple listeners can be used,
142          * and thus we honour getaddrinfo automatic protocol detection
143          * Once all backends do multi-listener, remove the PF_INET6
144          * branch entirely.
145          */
146         if (!addr->host || g_str_equal(addr->host, "")) {
147             return PF_INET6;
148         } else {
149             return PF_UNSPEC;
150         }
151     }
152     if ((addr->has_ipv6 && addr->ipv6) || (addr->has_ipv4 && !addr->ipv4)) {
153         return PF_INET6;
154     }
155     if ((addr->has_ipv4 && addr->ipv4) || (addr->has_ipv6 && !addr->ipv6)) {
156         return PF_INET;
157     }
158     return PF_UNSPEC;
159 }
160 
161 static int create_fast_reuse_socket(struct addrinfo *e)
162 {
163     int slisten = qemu_socket(e->ai_family, e->ai_socktype, e->ai_protocol);
164     if (slisten < 0) {
165         return -1;
166     }
167     socket_set_fast_reuse(slisten);
168     return slisten;
169 }
170 
171 static int try_bind(int socket, InetSocketAddress *saddr, struct addrinfo *e)
172 {
173 #ifndef IPV6_V6ONLY
174     return bind(socket, e->ai_addr, e->ai_addrlen);
175 #else
176     /*
177      * Deals with first & last cases in matrix in comment
178      * for inet_ai_family_from_address().
179      */
180     int v6only =
181         ((!saddr->has_ipv4 && !saddr->has_ipv6) ||
182          (saddr->has_ipv4 && saddr->ipv4 &&
183           saddr->has_ipv6 && saddr->ipv6)) ? 0 : 1;
184     int stat;
185 
186  rebind:
187     if (e->ai_family == PF_INET6) {
188         qemu_setsockopt(socket, IPPROTO_IPV6, IPV6_V6ONLY, &v6only,
189                         sizeof(v6only));
190     }
191 
192     stat = bind(socket, e->ai_addr, e->ai_addrlen);
193     if (!stat) {
194         return 0;
195     }
196 
197     /* If we got EADDRINUSE from an IPv6 bind & v6only is unset,
198      * it could be that the IPv4 port is already claimed, so retry
199      * with v6only set
200      */
201     if (e->ai_family == PF_INET6 && errno == EADDRINUSE && !v6only) {
202         v6only = 1;
203         goto rebind;
204     }
205     return stat;
206 #endif
207 }
208 
209 static int inet_listen_saddr(InetSocketAddress *saddr,
210                              int port_offset,
211                              int num,
212                              Error **errp)
213 {
214     struct addrinfo ai,*res,*e;
215     char port[33];
216     char uaddr[INET6_ADDRSTRLEN+1];
217     char uport[33];
218     int rc, port_min, port_max, p;
219     int slisten = -1;
220     int saved_errno = 0;
221     bool socket_created = false;
222     Error *err = NULL;
223 
224     if (saddr->keep_alive) {
225         error_setg(errp, "keep-alive option is not supported for passive "
226                    "sockets");
227         return -1;
228     }
229 
230     memset(&ai,0, sizeof(ai));
231     ai.ai_flags = AI_PASSIVE;
232     if (saddr->has_numeric && saddr->numeric) {
233         ai.ai_flags |= AI_NUMERICHOST | AI_NUMERICSERV;
234     }
235     ai.ai_family = inet_ai_family_from_address(saddr, &err);
236     ai.ai_socktype = SOCK_STREAM;
237 
238     if (err) {
239         error_propagate(errp, err);
240         return -1;
241     }
242 
243     if (saddr->host == NULL) {
244         error_setg(errp, "host not specified");
245         return -1;
246     }
247     if (saddr->port != NULL) {
248         pstrcpy(port, sizeof(port), saddr->port);
249     } else {
250         port[0] = '\0';
251     }
252 
253     /* lookup */
254     if (port_offset) {
255         unsigned long long baseport;
256         if (strlen(port) == 0) {
257             error_setg(errp, "port not specified");
258             return -1;
259         }
260         if (parse_uint_full(port, &baseport, 10) < 0) {
261             error_setg(errp, "can't convert to a number: %s", port);
262             return -1;
263         }
264         if (baseport > 65535 ||
265             baseport + port_offset > 65535) {
266             error_setg(errp, "port %s out of range", port);
267             return -1;
268         }
269         snprintf(port, sizeof(port), "%d", (int)baseport + port_offset);
270     }
271     rc = getaddrinfo(strlen(saddr->host) ? saddr->host : NULL,
272                      strlen(port) ? port : NULL, &ai, &res);
273     if (rc != 0) {
274         error_setg(errp, "address resolution failed for %s:%s: %s",
275                    saddr->host, port, gai_strerror(rc));
276         return -1;
277     }
278 
279     /* create socket + bind/listen */
280     for (e = res; e != NULL; e = e->ai_next) {
281         getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,
282                         uaddr,INET6_ADDRSTRLEN,uport,32,
283                         NI_NUMERICHOST | NI_NUMERICSERV);
284 
285         port_min = inet_getport(e);
286         port_max = saddr->has_to ? saddr->to + port_offset : port_min;
287         for (p = port_min; p <= port_max; p++) {
288             inet_setport(e, p);
289 
290             slisten = create_fast_reuse_socket(e);
291             if (slisten < 0) {
292                 /* First time we expect we might fail to create the socket
293                  * eg if 'e' has AF_INET6 but ipv6 kmod is not loaded.
294                  * Later iterations should always succeed if first iteration
295                  * worked though, so treat that as fatal.
296                  */
297                 if (p == port_min) {
298                     continue;
299                 } else {
300                     error_setg_errno(errp, errno,
301                                      "Failed to recreate failed listening socket");
302                     goto listen_failed;
303                 }
304             }
305             socket_created = true;
306 
307             rc = try_bind(slisten, saddr, e);
308             if (rc < 0) {
309                 if (errno != EADDRINUSE) {
310                     error_setg_errno(errp, errno, "Failed to bind socket");
311                     goto listen_failed;
312                 }
313             } else {
314                 if (!listen(slisten, num)) {
315                     goto listen_ok;
316                 }
317                 if (errno != EADDRINUSE) {
318                     error_setg_errno(errp, errno, "Failed to listen on socket");
319                     goto listen_failed;
320                 }
321             }
322             /* Someone else managed to bind to the same port and beat us
323              * to listen on it! Socket semantics does not allow us to
324              * recover from this situation, so we need to recreate the
325              * socket to allow bind attempts for subsequent ports:
326              */
327             closesocket(slisten);
328             slisten = -1;
329         }
330     }
331     error_setg_errno(errp, errno,
332                      socket_created ?
333                      "Failed to find an available port" :
334                      "Failed to create a socket");
335 listen_failed:
336     saved_errno = errno;
337     if (slisten >= 0) {
338         closesocket(slisten);
339     }
340     freeaddrinfo(res);
341     errno = saved_errno;
342     return -1;
343 
344 listen_ok:
345     freeaddrinfo(res);
346     return slisten;
347 }
348 
349 #ifdef _WIN32
350 #define QEMU_SOCKET_RC_INPROGRESS(rc) \
351     ((rc) == -EINPROGRESS || (rc) == -EWOULDBLOCK || (rc) == -WSAEALREADY)
352 #else
353 #define QEMU_SOCKET_RC_INPROGRESS(rc) \
354     ((rc) == -EINPROGRESS)
355 #endif
356 
357 static int inet_connect_addr(struct addrinfo *addr, Error **errp);
358 
359 static int inet_connect_addr(struct addrinfo *addr, Error **errp)
360 {
361     int sock, rc;
362 
363     sock = qemu_socket(addr->ai_family, addr->ai_socktype, addr->ai_protocol);
364     if (sock < 0) {
365         error_setg_errno(errp, errno, "Failed to create socket");
366         return -1;
367     }
368     socket_set_fast_reuse(sock);
369 
370     /* connect to peer */
371     do {
372         rc = 0;
373         if (connect(sock, addr->ai_addr, addr->ai_addrlen) < 0) {
374             rc = -errno;
375         }
376     } while (rc == -EINTR);
377 
378     if (rc < 0) {
379         error_setg_errno(errp, errno, "Failed to connect socket");
380         closesocket(sock);
381         return -1;
382     }
383 
384     return sock;
385 }
386 
387 static struct addrinfo *inet_parse_connect_saddr(InetSocketAddress *saddr,
388                                                  Error **errp)
389 {
390     struct addrinfo ai, *res;
391     int rc;
392     Error *err = NULL;
393     static int useV4Mapped = 1;
394 
395     memset(&ai, 0, sizeof(ai));
396 
397     ai.ai_flags = AI_CANONNAME | AI_ADDRCONFIG;
398     if (atomic_read(&useV4Mapped)) {
399         ai.ai_flags |= AI_V4MAPPED;
400     }
401     ai.ai_family = inet_ai_family_from_address(saddr, &err);
402     ai.ai_socktype = SOCK_STREAM;
403 
404     if (err) {
405         error_propagate(errp, err);
406         return NULL;
407     }
408 
409     if (saddr->host == NULL || saddr->port == NULL) {
410         error_setg(errp, "host and/or port not specified");
411         return NULL;
412     }
413 
414     /* lookup */
415     rc = getaddrinfo(saddr->host, saddr->port, &ai, &res);
416 
417     /* At least FreeBSD and OS-X 10.6 declare AI_V4MAPPED but
418      * then don't implement it in their getaddrinfo(). Detect
419      * this and retry without the flag since that's preferrable
420      * to a fatal error
421      */
422     if (rc == EAI_BADFLAGS &&
423         (ai.ai_flags & AI_V4MAPPED)) {
424         atomic_set(&useV4Mapped, 0);
425         ai.ai_flags &= ~AI_V4MAPPED;
426         rc = getaddrinfo(saddr->host, saddr->port, &ai, &res);
427     }
428     if (rc != 0) {
429         error_setg(errp, "address resolution failed for %s:%s: %s",
430                    saddr->host, saddr->port, gai_strerror(rc));
431         return NULL;
432     }
433     return res;
434 }
435 
436 /**
437  * Create a socket and connect it to an address.
438  *
439  * @saddr: Inet socket address specification
440  * @errp: set on error
441  *
442  * Returns: -1 on error, file descriptor on success.
443  */
444 int inet_connect_saddr(InetSocketAddress *saddr, Error **errp)
445 {
446     Error *local_err = NULL;
447     struct addrinfo *res, *e;
448     int sock = -1;
449 
450     res = inet_parse_connect_saddr(saddr, errp);
451     if (!res) {
452         return -1;
453     }
454 
455     for (e = res; e != NULL; e = e->ai_next) {
456         error_free(local_err);
457         local_err = NULL;
458         sock = inet_connect_addr(e, &local_err);
459         if (sock >= 0) {
460             break;
461         }
462     }
463 
464     if (sock < 0) {
465         error_propagate(errp, local_err);
466     }
467 
468     freeaddrinfo(res);
469 
470     if (saddr->keep_alive) {
471         int val = 1;
472         int ret = qemu_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
473                                   &val, sizeof(val));
474 
475         if (ret < 0) {
476             error_setg_errno(errp, errno, "Unable to set KEEPALIVE");
477             close(sock);
478             return -1;
479         }
480     }
481 
482     return sock;
483 }
484 
485 static int inet_dgram_saddr(InetSocketAddress *sraddr,
486                             InetSocketAddress *sladdr,
487                             Error **errp)
488 {
489     struct addrinfo ai, *peer = NULL, *local = NULL;
490     const char *addr;
491     const char *port;
492     int sock = -1, rc;
493     Error *err = NULL;
494 
495     /* lookup peer addr */
496     memset(&ai,0, sizeof(ai));
497     ai.ai_flags = AI_CANONNAME | AI_V4MAPPED | AI_ADDRCONFIG;
498     ai.ai_family = inet_ai_family_from_address(sraddr, &err);
499     ai.ai_socktype = SOCK_DGRAM;
500 
501     if (err) {
502         error_propagate(errp, err);
503         goto err;
504     }
505 
506     addr = sraddr->host;
507     port = sraddr->port;
508     if (addr == NULL || strlen(addr) == 0) {
509         addr = "localhost";
510     }
511     if (port == NULL || strlen(port) == 0) {
512         error_setg(errp, "remote port not specified");
513         goto err;
514     }
515 
516     if ((rc = getaddrinfo(addr, port, &ai, &peer)) != 0) {
517         error_setg(errp, "address resolution failed for %s:%s: %s", addr, port,
518                    gai_strerror(rc));
519         goto err;
520     }
521 
522     /* lookup local addr */
523     memset(&ai,0, sizeof(ai));
524     ai.ai_flags = AI_PASSIVE;
525     ai.ai_family = peer->ai_family;
526     ai.ai_socktype = SOCK_DGRAM;
527 
528     if (sladdr) {
529         addr = sladdr->host;
530         port = sladdr->port;
531         if (addr == NULL || strlen(addr) == 0) {
532             addr = NULL;
533         }
534         if (!port || strlen(port) == 0) {
535             port = "0";
536         }
537     } else {
538         addr = NULL;
539         port = "0";
540     }
541 
542     if ((rc = getaddrinfo(addr, port, &ai, &local)) != 0) {
543         error_setg(errp, "address resolution failed for %s:%s: %s", addr, port,
544                    gai_strerror(rc));
545         goto err;
546     }
547 
548     /* create socket */
549     sock = qemu_socket(peer->ai_family, peer->ai_socktype, peer->ai_protocol);
550     if (sock < 0) {
551         error_setg_errno(errp, errno, "Failed to create socket");
552         goto err;
553     }
554     socket_set_fast_reuse(sock);
555 
556     /* bind socket */
557     if (bind(sock, local->ai_addr, local->ai_addrlen) < 0) {
558         error_setg_errno(errp, errno, "Failed to bind socket");
559         goto err;
560     }
561 
562     /* connect to peer */
563     if (connect(sock,peer->ai_addr,peer->ai_addrlen) < 0) {
564         error_setg_errno(errp, errno, "Failed to connect socket");
565         goto err;
566     }
567 
568     freeaddrinfo(local);
569     freeaddrinfo(peer);
570     return sock;
571 
572 err:
573     if (sock != -1) {
574         closesocket(sock);
575     }
576     if (local) {
577         freeaddrinfo(local);
578     }
579     if (peer) {
580         freeaddrinfo(peer);
581     }
582 
583     return -1;
584 }
585 
586 /* compatibility wrapper */
587 static int inet_parse_flag(const char *flagname, const char *optstr, bool *val,
588                            Error **errp)
589 {
590     char *end;
591     size_t len;
592 
593     end = strstr(optstr, ",");
594     if (end) {
595         if (end[1] == ',') { /* Reject 'ipv6=on,,foo' */
596             error_setg(errp, "error parsing '%s' flag '%s'", flagname, optstr);
597             return -1;
598         }
599         len = end - optstr;
600     } else {
601         len = strlen(optstr);
602     }
603     if (len == 0 || (len == 3 && strncmp(optstr, "=on", len) == 0)) {
604         *val = true;
605     } else if (len == 4 && strncmp(optstr, "=off", len) == 0) {
606         *val = false;
607     } else {
608         error_setg(errp, "error parsing '%s' flag '%s'", flagname, optstr);
609         return -1;
610     }
611     return 0;
612 }
613 
614 int inet_parse(InetSocketAddress *addr, const char *str, Error **errp)
615 {
616     const char *optstr, *h;
617     char host[65];
618     char port[33];
619     int to;
620     int pos;
621     char *begin;
622 
623     memset(addr, 0, sizeof(*addr));
624 
625     /* parse address */
626     if (str[0] == ':') {
627         /* no host given */
628         host[0] = '\0';
629         if (sscanf(str, ":%32[^,]%n", port, &pos) != 1) {
630             error_setg(errp, "error parsing port in address '%s'", str);
631             return -1;
632         }
633     } else if (str[0] == '[') {
634         /* IPv6 addr */
635         if (sscanf(str, "[%64[^]]]:%32[^,]%n", host, port, &pos) != 2) {
636             error_setg(errp, "error parsing IPv6 address '%s'", str);
637             return -1;
638         }
639     } else {
640         /* hostname or IPv4 addr */
641         if (sscanf(str, "%64[^:]:%32[^,]%n", host, port, &pos) != 2) {
642             error_setg(errp, "error parsing address '%s'", str);
643             return -1;
644         }
645     }
646 
647     addr->host = g_strdup(host);
648     addr->port = g_strdup(port);
649 
650     /* parse options */
651     optstr = str + pos;
652     h = strstr(optstr, ",to=");
653     if (h) {
654         h += 4;
655         if (sscanf(h, "%d%n", &to, &pos) != 1 ||
656             (h[pos] != '\0' && h[pos] != ',')) {
657             error_setg(errp, "error parsing to= argument");
658             return -1;
659         }
660         addr->has_to = true;
661         addr->to = to;
662     }
663     begin = strstr(optstr, ",ipv4");
664     if (begin) {
665         if (inet_parse_flag("ipv4", begin + 5, &addr->ipv4, errp) < 0) {
666             return -1;
667         }
668         addr->has_ipv4 = true;
669     }
670     begin = strstr(optstr, ",ipv6");
671     if (begin) {
672         if (inet_parse_flag("ipv6", begin + 5, &addr->ipv6, errp) < 0) {
673             return -1;
674         }
675         addr->has_ipv6 = true;
676     }
677     begin = strstr(optstr, ",keep-alive");
678     if (begin) {
679         if (inet_parse_flag("keep-alive", begin + strlen(",keep-alive"),
680                             &addr->keep_alive, errp) < 0)
681         {
682             return -1;
683         }
684         addr->has_keep_alive = true;
685     }
686     return 0;
687 }
688 
689 
690 /**
691  * Create a blocking socket and connect it to an address.
692  *
693  * @str: address string
694  * @errp: set in case of an error
695  *
696  * Returns -1 in case of error, file descriptor on success
697  **/
698 int inet_connect(const char *str, Error **errp)
699 {
700     int sock = -1;
701     InetSocketAddress *addr = g_new(InetSocketAddress, 1);
702 
703     if (!inet_parse(addr, str, errp)) {
704         sock = inet_connect_saddr(addr, errp);
705     }
706     qapi_free_InetSocketAddress(addr);
707     return sock;
708 }
709 
710 #ifdef CONFIG_AF_VSOCK
711 static bool vsock_parse_vaddr_to_sockaddr(const VsockSocketAddress *vaddr,
712                                           struct sockaddr_vm *svm,
713                                           Error **errp)
714 {
715     unsigned long long val;
716 
717     memset(svm, 0, sizeof(*svm));
718     svm->svm_family = AF_VSOCK;
719 
720     if (parse_uint_full(vaddr->cid, &val, 10) < 0 ||
721         val > UINT32_MAX) {
722         error_setg(errp, "Failed to parse cid '%s'", vaddr->cid);
723         return false;
724     }
725     svm->svm_cid = val;
726 
727     if (parse_uint_full(vaddr->port, &val, 10) < 0 ||
728         val > UINT32_MAX) {
729         error_setg(errp, "Failed to parse port '%s'", vaddr->port);
730         return false;
731     }
732     svm->svm_port = val;
733 
734     return true;
735 }
736 
737 static int vsock_connect_addr(const struct sockaddr_vm *svm, Error **errp)
738 {
739     int sock, rc;
740 
741     sock = qemu_socket(AF_VSOCK, SOCK_STREAM, 0);
742     if (sock < 0) {
743         error_setg_errno(errp, errno, "Failed to create socket");
744         return -1;
745     }
746 
747     /* connect to peer */
748     do {
749         rc = 0;
750         if (connect(sock, (const struct sockaddr *)svm, sizeof(*svm)) < 0) {
751             rc = -errno;
752         }
753     } while (rc == -EINTR);
754 
755     if (rc < 0) {
756         error_setg_errno(errp, errno, "Failed to connect socket");
757         closesocket(sock);
758         return -1;
759     }
760 
761     return sock;
762 }
763 
764 static int vsock_connect_saddr(VsockSocketAddress *vaddr, Error **errp)
765 {
766     struct sockaddr_vm svm;
767     int sock = -1;
768 
769     if (!vsock_parse_vaddr_to_sockaddr(vaddr, &svm, errp)) {
770         return -1;
771     }
772 
773     sock = vsock_connect_addr(&svm, errp);
774 
775     return sock;
776 }
777 
778 static int vsock_listen_saddr(VsockSocketAddress *vaddr,
779                               int num,
780                               Error **errp)
781 {
782     struct sockaddr_vm svm;
783     int slisten;
784 
785     if (!vsock_parse_vaddr_to_sockaddr(vaddr, &svm, errp)) {
786         return -1;
787     }
788 
789     slisten = qemu_socket(AF_VSOCK, SOCK_STREAM, 0);
790     if (slisten < 0) {
791         error_setg_errno(errp, errno, "Failed to create socket");
792         return -1;
793     }
794 
795     if (bind(slisten, (const struct sockaddr *)&svm, sizeof(svm)) != 0) {
796         error_setg_errno(errp, errno, "Failed to bind socket");
797         closesocket(slisten);
798         return -1;
799     }
800 
801     if (listen(slisten, num) != 0) {
802         error_setg_errno(errp, errno, "Failed to listen on socket");
803         closesocket(slisten);
804         return -1;
805     }
806     return slisten;
807 }
808 
809 static int vsock_parse(VsockSocketAddress *addr, const char *str,
810                        Error **errp)
811 {
812     char cid[33];
813     char port[33];
814     int n;
815 
816     if (sscanf(str, "%32[^:]:%32[^,]%n", cid, port, &n) != 2) {
817         error_setg(errp, "error parsing address '%s'", str);
818         return -1;
819     }
820     if (str[n] != '\0') {
821         error_setg(errp, "trailing characters in address '%s'", str);
822         return -1;
823     }
824 
825     addr->cid = g_strdup(cid);
826     addr->port = g_strdup(port);
827     return 0;
828 }
829 #else
830 static void vsock_unsupported(Error **errp)
831 {
832     error_setg(errp, "socket family AF_VSOCK unsupported");
833 }
834 
835 static int vsock_connect_saddr(VsockSocketAddress *vaddr, Error **errp)
836 {
837     vsock_unsupported(errp);
838     return -1;
839 }
840 
841 static int vsock_listen_saddr(VsockSocketAddress *vaddr,
842                               int num,
843                               Error **errp)
844 {
845     vsock_unsupported(errp);
846     return -1;
847 }
848 
849 static int vsock_parse(VsockSocketAddress *addr, const char *str,
850                         Error **errp)
851 {
852     vsock_unsupported(errp);
853     return -1;
854 }
855 #endif /* CONFIG_AF_VSOCK */
856 
857 #ifndef _WIN32
858 
859 static int unix_listen_saddr(UnixSocketAddress *saddr,
860                              int num,
861                              Error **errp)
862 {
863     struct sockaddr_un un;
864     int sock, fd;
865     char *pathbuf = NULL;
866     const char *path;
867     size_t pathlen;
868 
869     sock = qemu_socket(PF_UNIX, SOCK_STREAM, 0);
870     if (sock < 0) {
871         error_setg_errno(errp, errno, "Failed to create Unix socket");
872         return -1;
873     }
874 
875     if (saddr->path && saddr->path[0]) {
876         path = saddr->path;
877     } else {
878         const char *tmpdir = getenv("TMPDIR");
879         tmpdir = tmpdir ? tmpdir : "/tmp";
880         path = pathbuf = g_strdup_printf("%s/qemu-socket-XXXXXX", tmpdir);
881     }
882 
883     pathlen = strlen(path);
884     if (pathlen > sizeof(un.sun_path)) {
885         error_setg(errp, "UNIX socket path '%s' is too long", path);
886         error_append_hint(errp, "Path must be less than %zu bytes\n",
887                           sizeof(un.sun_path));
888         goto err;
889     }
890 
891     if (pathbuf != NULL) {
892         /*
893          * This dummy fd usage silences the mktemp() unsecure warning.
894          * Using mkstemp() doesn't make things more secure here
895          * though.  bind() complains about existing files, so we have
896          * to unlink first and thus re-open the race window.  The
897          * worst case possible is bind() failing, i.e. a DoS attack.
898          */
899         fd = mkstemp(pathbuf);
900         if (fd < 0) {
901             error_setg_errno(errp, errno,
902                              "Failed to make a temporary socket %s", pathbuf);
903             goto err;
904         }
905         close(fd);
906     }
907 
908     if (unlink(path) < 0 && errno != ENOENT) {
909         error_setg_errno(errp, errno,
910                          "Failed to unlink socket %s", path);
911         goto err;
912     }
913 
914     memset(&un, 0, sizeof(un));
915     un.sun_family = AF_UNIX;
916     memcpy(un.sun_path, path, pathlen);
917 
918     if (bind(sock, (struct sockaddr*) &un, sizeof(un)) < 0) {
919         error_setg_errno(errp, errno, "Failed to bind socket to %s", path);
920         goto err;
921     }
922     if (listen(sock, num) < 0) {
923         error_setg_errno(errp, errno, "Failed to listen on socket");
924         goto err;
925     }
926 
927     g_free(pathbuf);
928     return sock;
929 
930 err:
931     g_free(pathbuf);
932     closesocket(sock);
933     return -1;
934 }
935 
936 static int unix_connect_saddr(UnixSocketAddress *saddr, Error **errp)
937 {
938     struct sockaddr_un un;
939     int sock, rc;
940     size_t pathlen;
941 
942     if (saddr->path == NULL) {
943         error_setg(errp, "unix connect: no path specified");
944         return -1;
945     }
946 
947     sock = qemu_socket(PF_UNIX, SOCK_STREAM, 0);
948     if (sock < 0) {
949         error_setg_errno(errp, errno, "Failed to create socket");
950         return -1;
951     }
952 
953     pathlen = strlen(saddr->path);
954     if (pathlen > sizeof(un.sun_path)) {
955         error_setg(errp, "UNIX socket path '%s' is too long", saddr->path);
956         error_append_hint(errp, "Path must be less than %zu bytes\n",
957                           sizeof(un.sun_path));
958         goto err;
959     }
960 
961     memset(&un, 0, sizeof(un));
962     un.sun_family = AF_UNIX;
963     memcpy(un.sun_path, saddr->path, pathlen);
964 
965     /* connect to peer */
966     do {
967         rc = 0;
968         if (connect(sock, (struct sockaddr *) &un, sizeof(un)) < 0) {
969             rc = -errno;
970         }
971     } while (rc == -EINTR);
972 
973     if (rc < 0) {
974         error_setg_errno(errp, -rc, "Failed to connect socket %s",
975                          saddr->path);
976         goto err;
977     }
978 
979     return sock;
980 
981  err:
982     close(sock);
983     return -1;
984 }
985 
986 #else
987 
988 static int unix_listen_saddr(UnixSocketAddress *saddr,
989                              int num,
990                              Error **errp)
991 {
992     error_setg(errp, "unix sockets are not available on windows");
993     errno = ENOTSUP;
994     return -1;
995 }
996 
997 static int unix_connect_saddr(UnixSocketAddress *saddr, Error **errp)
998 {
999     error_setg(errp, "unix sockets are not available on windows");
1000     errno = ENOTSUP;
1001     return -1;
1002 }
1003 #endif
1004 
1005 /* compatibility wrapper */
1006 int unix_listen(const char *str, Error **errp)
1007 {
1008     UnixSocketAddress *saddr;
1009     int sock;
1010 
1011     saddr = g_new0(UnixSocketAddress, 1);
1012     saddr->path = g_strdup(str);
1013     sock = unix_listen_saddr(saddr, 1, errp);
1014     qapi_free_UnixSocketAddress(saddr);
1015     return sock;
1016 }
1017 
1018 int unix_connect(const char *path, Error **errp)
1019 {
1020     UnixSocketAddress *saddr;
1021     int sock;
1022 
1023     saddr = g_new0(UnixSocketAddress, 1);
1024     saddr->path = g_strdup(path);
1025     sock = unix_connect_saddr(saddr, errp);
1026     qapi_free_UnixSocketAddress(saddr);
1027     return sock;
1028 }
1029 
1030 
1031 SocketAddress *socket_parse(const char *str, Error **errp)
1032 {
1033     SocketAddress *addr;
1034 
1035     addr = g_new0(SocketAddress, 1);
1036     if (strstart(str, "unix:", NULL)) {
1037         if (str[5] == '\0') {
1038             error_setg(errp, "invalid Unix socket address");
1039             goto fail;
1040         } else {
1041             addr->type = SOCKET_ADDRESS_TYPE_UNIX;
1042             addr->u.q_unix.path = g_strdup(str + 5);
1043         }
1044     } else if (strstart(str, "fd:", NULL)) {
1045         if (str[3] == '\0') {
1046             error_setg(errp, "invalid file descriptor address");
1047             goto fail;
1048         } else {
1049             addr->type = SOCKET_ADDRESS_TYPE_FD;
1050             addr->u.fd.str = g_strdup(str + 3);
1051         }
1052     } else if (strstart(str, "vsock:", NULL)) {
1053         addr->type = SOCKET_ADDRESS_TYPE_VSOCK;
1054         if (vsock_parse(&addr->u.vsock, str + strlen("vsock:"), errp)) {
1055             goto fail;
1056         }
1057     } else {
1058         addr->type = SOCKET_ADDRESS_TYPE_INET;
1059         if (inet_parse(&addr->u.inet, str, errp)) {
1060             goto fail;
1061         }
1062     }
1063     return addr;
1064 
1065 fail:
1066     qapi_free_SocketAddress(addr);
1067     return NULL;
1068 }
1069 
1070 static int socket_get_fd(const char *fdstr, int num, Error **errp)
1071 {
1072     int fd;
1073     if (num != 1) {
1074         error_setg_errno(errp, EINVAL, "socket_get_fd: too many connections");
1075         return -1;
1076     }
1077     if (cur_mon) {
1078         fd = monitor_get_fd(cur_mon, fdstr, errp);
1079         if (fd < 0) {
1080             return -1;
1081         }
1082     } else {
1083         if (qemu_strtoi(fdstr, NULL, 10, &fd) < 0) {
1084             error_setg_errno(errp, errno,
1085                              "Unable to parse FD number %s",
1086                              fdstr);
1087             return -1;
1088         }
1089     }
1090     if (!fd_is_socket(fd)) {
1091         error_setg(errp, "File descriptor '%s' is not a socket", fdstr);
1092         close(fd);
1093         return -1;
1094     }
1095     return fd;
1096 }
1097 
1098 int socket_connect(SocketAddress *addr, Error **errp)
1099 {
1100     int fd;
1101 
1102     switch (addr->type) {
1103     case SOCKET_ADDRESS_TYPE_INET:
1104         fd = inet_connect_saddr(&addr->u.inet, errp);
1105         break;
1106 
1107     case SOCKET_ADDRESS_TYPE_UNIX:
1108         fd = unix_connect_saddr(&addr->u.q_unix, errp);
1109         break;
1110 
1111     case SOCKET_ADDRESS_TYPE_FD:
1112         fd = socket_get_fd(addr->u.fd.str, 1, errp);
1113         break;
1114 
1115     case SOCKET_ADDRESS_TYPE_VSOCK:
1116         fd = vsock_connect_saddr(&addr->u.vsock, errp);
1117         break;
1118 
1119     default:
1120         abort();
1121     }
1122     return fd;
1123 }
1124 
1125 int socket_listen(SocketAddress *addr, int num, Error **errp)
1126 {
1127     int fd;
1128 
1129     trace_socket_listen(num);
1130     switch (addr->type) {
1131     case SOCKET_ADDRESS_TYPE_INET:
1132         fd = inet_listen_saddr(&addr->u.inet, 0, num, errp);
1133         break;
1134 
1135     case SOCKET_ADDRESS_TYPE_UNIX:
1136         fd = unix_listen_saddr(&addr->u.q_unix, num, errp);
1137         break;
1138 
1139     case SOCKET_ADDRESS_TYPE_FD:
1140         fd = socket_get_fd(addr->u.fd.str, num, errp);
1141         break;
1142 
1143     case SOCKET_ADDRESS_TYPE_VSOCK:
1144         fd = vsock_listen_saddr(&addr->u.vsock, num, errp);
1145         break;
1146 
1147     default:
1148         abort();
1149     }
1150     return fd;
1151 }
1152 
1153 void socket_listen_cleanup(int fd, Error **errp)
1154 {
1155     SocketAddress *addr;
1156 
1157     addr = socket_local_address(fd, errp);
1158     if (!addr) {
1159         return;
1160     }
1161 
1162     if (addr->type == SOCKET_ADDRESS_TYPE_UNIX
1163         && addr->u.q_unix.path) {
1164         if (unlink(addr->u.q_unix.path) < 0 && errno != ENOENT) {
1165             error_setg_errno(errp, errno,
1166                              "Failed to unlink socket %s",
1167                              addr->u.q_unix.path);
1168         }
1169     }
1170 
1171     qapi_free_SocketAddress(addr);
1172 }
1173 
1174 int socket_dgram(SocketAddress *remote, SocketAddress *local, Error **errp)
1175 {
1176     int fd;
1177 
1178     /*
1179      * TODO SOCKET_ADDRESS_TYPE_FD when fd is AF_INET or AF_INET6
1180      * (although other address families can do SOCK_DGRAM, too)
1181      */
1182     switch (remote->type) {
1183     case SOCKET_ADDRESS_TYPE_INET:
1184         fd = inet_dgram_saddr(&remote->u.inet,
1185                               local ? &local->u.inet : NULL, errp);
1186         break;
1187 
1188     default:
1189         error_setg(errp, "socket type unsupported for datagram");
1190         fd = -1;
1191     }
1192     return fd;
1193 }
1194 
1195 
1196 static SocketAddress *
1197 socket_sockaddr_to_address_inet(struct sockaddr_storage *sa,
1198                                 socklen_t salen,
1199                                 Error **errp)
1200 {
1201     char host[NI_MAXHOST];
1202     char serv[NI_MAXSERV];
1203     SocketAddress *addr;
1204     InetSocketAddress *inet;
1205     int ret;
1206 
1207     ret = getnameinfo((struct sockaddr *)sa, salen,
1208                       host, sizeof(host),
1209                       serv, sizeof(serv),
1210                       NI_NUMERICHOST | NI_NUMERICSERV);
1211     if (ret != 0) {
1212         error_setg(errp, "Cannot format numeric socket address: %s",
1213                    gai_strerror(ret));
1214         return NULL;
1215     }
1216 
1217     addr = g_new0(SocketAddress, 1);
1218     addr->type = SOCKET_ADDRESS_TYPE_INET;
1219     inet = &addr->u.inet;
1220     inet->host = g_strdup(host);
1221     inet->port = g_strdup(serv);
1222     if (sa->ss_family == AF_INET) {
1223         inet->has_ipv4 = inet->ipv4 = true;
1224     } else {
1225         inet->has_ipv6 = inet->ipv6 = true;
1226     }
1227 
1228     return addr;
1229 }
1230 
1231 
1232 #ifndef WIN32
1233 static SocketAddress *
1234 socket_sockaddr_to_address_unix(struct sockaddr_storage *sa,
1235                                 socklen_t salen,
1236                                 Error **errp)
1237 {
1238     SocketAddress *addr;
1239     struct sockaddr_un *su = (struct sockaddr_un *)sa;
1240 
1241     addr = g_new0(SocketAddress, 1);
1242     addr->type = SOCKET_ADDRESS_TYPE_UNIX;
1243     if (su->sun_path[0]) {
1244         addr->u.q_unix.path = g_strndup(su->sun_path, sizeof(su->sun_path));
1245     }
1246 
1247     return addr;
1248 }
1249 #endif /* WIN32 */
1250 
1251 #ifdef CONFIG_AF_VSOCK
1252 static SocketAddress *
1253 socket_sockaddr_to_address_vsock(struct sockaddr_storage *sa,
1254                                  socklen_t salen,
1255                                  Error **errp)
1256 {
1257     SocketAddress *addr;
1258     VsockSocketAddress *vaddr;
1259     struct sockaddr_vm *svm = (struct sockaddr_vm *)sa;
1260 
1261     addr = g_new0(SocketAddress, 1);
1262     addr->type = SOCKET_ADDRESS_TYPE_VSOCK;
1263     vaddr = &addr->u.vsock;
1264     vaddr->cid = g_strdup_printf("%u", svm->svm_cid);
1265     vaddr->port = g_strdup_printf("%u", svm->svm_port);
1266 
1267     return addr;
1268 }
1269 #endif /* CONFIG_AF_VSOCK */
1270 
1271 SocketAddress *
1272 socket_sockaddr_to_address(struct sockaddr_storage *sa,
1273                            socklen_t salen,
1274                            Error **errp)
1275 {
1276     switch (sa->ss_family) {
1277     case AF_INET:
1278     case AF_INET6:
1279         return socket_sockaddr_to_address_inet(sa, salen, errp);
1280 
1281 #ifndef WIN32
1282     case AF_UNIX:
1283         return socket_sockaddr_to_address_unix(sa, salen, errp);
1284 #endif /* WIN32 */
1285 
1286 #ifdef CONFIG_AF_VSOCK
1287     case AF_VSOCK:
1288         return socket_sockaddr_to_address_vsock(sa, salen, errp);
1289 #endif
1290 
1291     default:
1292         error_setg(errp, "socket family %d unsupported",
1293                    sa->ss_family);
1294         return NULL;
1295     }
1296     return 0;
1297 }
1298 
1299 
1300 SocketAddress *socket_local_address(int fd, Error **errp)
1301 {
1302     struct sockaddr_storage ss;
1303     socklen_t sslen = sizeof(ss);
1304 
1305     if (getsockname(fd, (struct sockaddr *)&ss, &sslen) < 0) {
1306         error_setg_errno(errp, errno, "%s",
1307                          "Unable to query local socket address");
1308         return NULL;
1309     }
1310 
1311     return socket_sockaddr_to_address(&ss, sslen, errp);
1312 }
1313 
1314 
1315 SocketAddress *socket_remote_address(int fd, Error **errp)
1316 {
1317     struct sockaddr_storage ss;
1318     socklen_t sslen = sizeof(ss);
1319 
1320     if (getpeername(fd, (struct sockaddr *)&ss, &sslen) < 0) {
1321         error_setg_errno(errp, errno, "%s",
1322                          "Unable to query remote socket address");
1323         return NULL;
1324     }
1325 
1326     return socket_sockaddr_to_address(&ss, sslen, errp);
1327 }
1328 
1329 
1330 SocketAddress *socket_address_flatten(SocketAddressLegacy *addr_legacy)
1331 {
1332     SocketAddress *addr;
1333 
1334     if (!addr_legacy) {
1335         return NULL;
1336     }
1337 
1338     addr = g_new(SocketAddress, 1);
1339 
1340     switch (addr_legacy->type) {
1341     case SOCKET_ADDRESS_LEGACY_KIND_INET:
1342         addr->type = SOCKET_ADDRESS_TYPE_INET;
1343         QAPI_CLONE_MEMBERS(InetSocketAddress, &addr->u.inet,
1344                            addr_legacy->u.inet.data);
1345         break;
1346     case SOCKET_ADDRESS_LEGACY_KIND_UNIX:
1347         addr->type = SOCKET_ADDRESS_TYPE_UNIX;
1348         QAPI_CLONE_MEMBERS(UnixSocketAddress, &addr->u.q_unix,
1349                            addr_legacy->u.q_unix.data);
1350         break;
1351     case SOCKET_ADDRESS_LEGACY_KIND_VSOCK:
1352         addr->type = SOCKET_ADDRESS_TYPE_VSOCK;
1353         QAPI_CLONE_MEMBERS(VsockSocketAddress, &addr->u.vsock,
1354                            addr_legacy->u.vsock.data);
1355         break;
1356     case SOCKET_ADDRESS_LEGACY_KIND_FD:
1357         addr->type = SOCKET_ADDRESS_TYPE_FD;
1358         QAPI_CLONE_MEMBERS(String, &addr->u.fd, addr_legacy->u.fd.data);
1359         break;
1360     default:
1361         abort();
1362     }
1363 
1364     return addr;
1365 }
1366