xref: /openbmc/qemu/util/qemu-sockets.c (revision bb2e0039)
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/clone-visitor.h"
30 #include "qapi/qobject-input-visitor.h"
31 #include "qapi/qobject-output-visitor.h"
32 #include "qapi-visit.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 /*
96  * Matrix we're trying to apply
97  *
98  *  ipv4  ipv6   family
99  *   -     -       PF_UNSPEC
100  *   -     f       PF_INET
101  *   -     t       PF_INET6
102  *   f     -       PF_INET6
103  *   f     f       <error>
104  *   f     t       PF_INET6
105  *   t     -       PF_INET
106  *   t     f       PF_INET
107  *   t     t       PF_INET6/PF_UNSPEC
108  *
109  * NB, this matrix is only about getting the necessary results
110  * from getaddrinfo(). Some of the cases require further work
111  * after reading results from getaddrinfo in order to fully
112  * apply the logic the end user wants.
113  *
114  * In the first and last cases, we must set IPV6_V6ONLY=0
115  * when binding, to allow a single listener to potentially
116  * accept both IPv4+6 addresses.
117  */
118 int inet_ai_family_from_address(InetSocketAddress *addr,
119                                 Error **errp)
120 {
121     if (addr->has_ipv6 && addr->has_ipv4 &&
122         !addr->ipv6 && !addr->ipv4) {
123         error_setg(errp, "Cannot disable IPv4 and IPv6 at same time");
124         return PF_UNSPEC;
125     }
126     if ((addr->has_ipv6 && addr->ipv6) && (addr->has_ipv4 && addr->ipv4)) {
127         /*
128          * Some backends can only do a single listener. In that case
129          * we want empty hostname to resolve to "::" and then use the
130          * flag IPV6_V6ONLY==0 to get both protocols on 1 socket. This
131          * doesn't work for addresses other than "", so they're just
132          * inevitably broken until multiple listeners can be used,
133          * and thus we honour getaddrinfo automatic protocol detection
134          * Once all backends do multi-listener, remove the PF_INET6
135          * branch entirely.
136          */
137         if (!addr->host || g_str_equal(addr->host, "")) {
138             return PF_INET6;
139         } else {
140             return PF_UNSPEC;
141         }
142     }
143     if ((addr->has_ipv6 && addr->ipv6) || (addr->has_ipv4 && !addr->ipv4)) {
144         return PF_INET6;
145     }
146     if ((addr->has_ipv4 && addr->ipv4) || (addr->has_ipv6 && !addr->ipv6)) {
147         return PF_INET;
148     }
149     return PF_UNSPEC;
150 }
151 
152 static int inet_listen_saddr(InetSocketAddress *saddr,
153                              int port_offset,
154                              bool update_addr,
155                              Error **errp)
156 {
157     struct addrinfo ai,*res,*e;
158     char port[33];
159     char uaddr[INET6_ADDRSTRLEN+1];
160     char uport[33];
161     int slisten, rc, port_min, port_max, p;
162     Error *err = NULL;
163 
164     memset(&ai,0, sizeof(ai));
165     ai.ai_flags = AI_PASSIVE;
166     if (saddr->has_numeric && saddr->numeric) {
167         ai.ai_flags |= AI_NUMERICHOST | AI_NUMERICSERV;
168     }
169     ai.ai_family = inet_ai_family_from_address(saddr, &err);
170     ai.ai_socktype = SOCK_STREAM;
171 
172     if (err) {
173         error_propagate(errp, err);
174         return -1;
175     }
176 
177     if (saddr->host == NULL) {
178         error_setg(errp, "host not specified");
179         return -1;
180     }
181     if (saddr->port != NULL) {
182         pstrcpy(port, sizeof(port), saddr->port);
183     } else {
184         port[0] = '\0';
185     }
186 
187     /* lookup */
188     if (port_offset) {
189         unsigned long long baseport;
190         if (strlen(port) == 0) {
191             error_setg(errp, "port not specified");
192             return -1;
193         }
194         if (parse_uint_full(port, &baseport, 10) < 0) {
195             error_setg(errp, "can't convert to a number: %s", port);
196             return -1;
197         }
198         if (baseport > 65535 ||
199             baseport + port_offset > 65535) {
200             error_setg(errp, "port %s out of range", port);
201             return -1;
202         }
203         snprintf(port, sizeof(port), "%d", (int)baseport + port_offset);
204     }
205     rc = getaddrinfo(strlen(saddr->host) ? saddr->host : NULL,
206                      strlen(port) ? port : NULL, &ai, &res);
207     if (rc != 0) {
208         error_setg(errp, "address resolution failed for %s:%s: %s",
209                    saddr->host, port, gai_strerror(rc));
210         return -1;
211     }
212 
213     /* create socket + bind */
214     for (e = res; e != NULL; e = e->ai_next) {
215         getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,
216 		        uaddr,INET6_ADDRSTRLEN,uport,32,
217 		        NI_NUMERICHOST | NI_NUMERICSERV);
218         slisten = qemu_socket(e->ai_family, e->ai_socktype, e->ai_protocol);
219         if (slisten < 0) {
220             if (!e->ai_next) {
221                 error_setg_errno(errp, errno, "Failed to create socket");
222             }
223             continue;
224         }
225 
226         socket_set_fast_reuse(slisten);
227 
228         port_min = inet_getport(e);
229         port_max = saddr->has_to ? saddr->to + port_offset : port_min;
230         for (p = port_min; p <= port_max; p++) {
231 #ifdef IPV6_V6ONLY
232             /*
233              * Deals with first & last cases in matrix in comment
234              * for inet_ai_family_from_address().
235              */
236             int v6only =
237                 ((!saddr->has_ipv4 && !saddr->has_ipv6) ||
238                  (saddr->has_ipv4 && saddr->ipv4 &&
239                   saddr->has_ipv6 && saddr->ipv6)) ? 0 : 1;
240 #endif
241             inet_setport(e, p);
242 #ifdef IPV6_V6ONLY
243         rebind:
244             if (e->ai_family == PF_INET6) {
245                 qemu_setsockopt(slisten, IPPROTO_IPV6, IPV6_V6ONLY, &v6only,
246                                 sizeof(v6only));
247             }
248 #endif
249             if (bind(slisten, e->ai_addr, e->ai_addrlen) == 0) {
250                 goto listen;
251             }
252 
253 #ifdef IPV6_V6ONLY
254             /* If we got EADDRINUSE from an IPv6 bind & V6ONLY is unset,
255              * it could be that the IPv4 port is already claimed, so retry
256              * with V6ONLY set
257              */
258             if (e->ai_family == PF_INET6 && errno == EADDRINUSE && !v6only) {
259                 v6only = 1;
260                 goto rebind;
261             }
262 #endif
263 
264             if (p == port_max) {
265                 if (!e->ai_next) {
266                     error_setg_errno(errp, errno, "Failed to bind socket");
267                 }
268             }
269         }
270         closesocket(slisten);
271     }
272     freeaddrinfo(res);
273     return -1;
274 
275 listen:
276     if (listen(slisten,1) != 0) {
277         error_setg_errno(errp, errno, "Failed to listen on socket");
278         closesocket(slisten);
279         freeaddrinfo(res);
280         return -1;
281     }
282     if (update_addr) {
283         g_free(saddr->host);
284         saddr->host = g_strdup(uaddr);
285         g_free(saddr->port);
286         saddr->port = g_strdup_printf("%d",
287                                       inet_getport(e) - port_offset);
288         saddr->has_ipv6 = saddr->ipv6 = e->ai_family == PF_INET6;
289         saddr->has_ipv4 = saddr->ipv4 = e->ai_family != PF_INET6;
290     }
291     freeaddrinfo(res);
292     return slisten;
293 }
294 
295 #ifdef _WIN32
296 #define QEMU_SOCKET_RC_INPROGRESS(rc) \
297     ((rc) == -EINPROGRESS || (rc) == -EWOULDBLOCK || (rc) == -WSAEALREADY)
298 #else
299 #define QEMU_SOCKET_RC_INPROGRESS(rc) \
300     ((rc) == -EINPROGRESS)
301 #endif
302 
303 static int inet_connect_addr(struct addrinfo *addr, Error **errp);
304 
305 static int inet_connect_addr(struct addrinfo *addr, Error **errp)
306 {
307     int sock, rc;
308 
309     sock = qemu_socket(addr->ai_family, addr->ai_socktype, addr->ai_protocol);
310     if (sock < 0) {
311         error_setg_errno(errp, errno, "Failed to create socket");
312         return -1;
313     }
314     socket_set_fast_reuse(sock);
315 
316     /* connect to peer */
317     do {
318         rc = 0;
319         if (connect(sock, addr->ai_addr, addr->ai_addrlen) < 0) {
320             rc = -errno;
321         }
322     } while (rc == -EINTR);
323 
324     if (rc < 0) {
325         error_setg_errno(errp, errno, "Failed to connect socket");
326         closesocket(sock);
327         return -1;
328     }
329 
330     return sock;
331 }
332 
333 static struct addrinfo *inet_parse_connect_saddr(InetSocketAddress *saddr,
334                                                  Error **errp)
335 {
336     struct addrinfo ai, *res;
337     int rc;
338     Error *err = NULL;
339     static int useV4Mapped = 1;
340 
341     memset(&ai, 0, sizeof(ai));
342 
343     ai.ai_flags = AI_CANONNAME | AI_ADDRCONFIG;
344     if (atomic_read(&useV4Mapped)) {
345         ai.ai_flags |= AI_V4MAPPED;
346     }
347     ai.ai_family = inet_ai_family_from_address(saddr, &err);
348     ai.ai_socktype = SOCK_STREAM;
349 
350     if (err) {
351         error_propagate(errp, err);
352         return NULL;
353     }
354 
355     if (saddr->host == NULL || saddr->port == NULL) {
356         error_setg(errp, "host and/or port not specified");
357         return NULL;
358     }
359 
360     /* lookup */
361     rc = getaddrinfo(saddr->host, saddr->port, &ai, &res);
362 
363     /* At least FreeBSD and OS-X 10.6 declare AI_V4MAPPED but
364      * then don't implement it in their getaddrinfo(). Detect
365      * this and retry without the flag since that's preferrable
366      * to a fatal error
367      */
368     if (rc == EAI_BADFLAGS &&
369         (ai.ai_flags & AI_V4MAPPED)) {
370         atomic_set(&useV4Mapped, 0);
371         ai.ai_flags &= ~AI_V4MAPPED;
372         rc = getaddrinfo(saddr->host, saddr->port, &ai, &res);
373     }
374     if (rc != 0) {
375         error_setg(errp, "address resolution failed for %s:%s: %s",
376                    saddr->host, saddr->port, gai_strerror(rc));
377         return NULL;
378     }
379     return res;
380 }
381 
382 /**
383  * Create a socket and connect it to an address.
384  *
385  * @saddr: Inet socket address specification
386  * @errp: set on error
387  *
388  * Returns: -1 on error, file descriptor on success.
389  */
390 int inet_connect_saddr(InetSocketAddress *saddr, Error **errp)
391 {
392     Error *local_err = NULL;
393     struct addrinfo *res, *e;
394     int sock = -1;
395 
396     res = inet_parse_connect_saddr(saddr, errp);
397     if (!res) {
398         return -1;
399     }
400 
401     for (e = res; e != NULL; e = e->ai_next) {
402         error_free(local_err);
403         local_err = NULL;
404         sock = inet_connect_addr(e, &local_err);
405         if (sock >= 0) {
406             break;
407         }
408     }
409 
410     if (sock < 0) {
411         error_propagate(errp, local_err);
412     }
413 
414     freeaddrinfo(res);
415     return sock;
416 }
417 
418 static int inet_dgram_saddr(InetSocketAddress *sraddr,
419                             InetSocketAddress *sladdr,
420                             Error **errp)
421 {
422     struct addrinfo ai, *peer = NULL, *local = NULL;
423     const char *addr;
424     const char *port;
425     int sock = -1, rc;
426     Error *err = NULL;
427 
428     /* lookup peer addr */
429     memset(&ai,0, sizeof(ai));
430     ai.ai_flags = AI_CANONNAME | AI_V4MAPPED | AI_ADDRCONFIG;
431     ai.ai_family = inet_ai_family_from_address(sraddr, &err);
432     ai.ai_socktype = SOCK_DGRAM;
433 
434     if (err) {
435         error_propagate(errp, err);
436         goto err;
437     }
438 
439     addr = sraddr->host;
440     port = sraddr->port;
441     if (addr == NULL || strlen(addr) == 0) {
442         addr = "localhost";
443     }
444     if (port == NULL || strlen(port) == 0) {
445         error_setg(errp, "remote port not specified");
446         goto err;
447     }
448 
449     if ((rc = getaddrinfo(addr, port, &ai, &peer)) != 0) {
450         error_setg(errp, "address resolution failed for %s:%s: %s", addr, port,
451                    gai_strerror(rc));
452         goto err;
453     }
454 
455     /* lookup local addr */
456     memset(&ai,0, sizeof(ai));
457     ai.ai_flags = AI_PASSIVE;
458     ai.ai_family = peer->ai_family;
459     ai.ai_socktype = SOCK_DGRAM;
460 
461     if (sladdr) {
462         addr = sladdr->host;
463         port = sladdr->port;
464         if (addr == NULL || strlen(addr) == 0) {
465             addr = NULL;
466         }
467         if (!port || strlen(port) == 0) {
468             port = "0";
469         }
470     } else {
471         addr = NULL;
472         port = "0";
473     }
474 
475     if ((rc = getaddrinfo(addr, port, &ai, &local)) != 0) {
476         error_setg(errp, "address resolution failed for %s:%s: %s", addr, port,
477                    gai_strerror(rc));
478         goto err;
479     }
480 
481     /* create socket */
482     sock = qemu_socket(peer->ai_family, peer->ai_socktype, peer->ai_protocol);
483     if (sock < 0) {
484         error_setg_errno(errp, errno, "Failed to create socket");
485         goto err;
486     }
487     socket_set_fast_reuse(sock);
488 
489     /* bind socket */
490     if (bind(sock, local->ai_addr, local->ai_addrlen) < 0) {
491         error_setg_errno(errp, errno, "Failed to bind socket");
492         goto err;
493     }
494 
495     /* connect to peer */
496     if (connect(sock,peer->ai_addr,peer->ai_addrlen) < 0) {
497         error_setg_errno(errp, errno, "Failed to connect socket");
498         goto err;
499     }
500 
501     freeaddrinfo(local);
502     freeaddrinfo(peer);
503     return sock;
504 
505 err:
506     if (sock != -1) {
507         closesocket(sock);
508     }
509     if (local) {
510         freeaddrinfo(local);
511     }
512     if (peer) {
513         freeaddrinfo(peer);
514     }
515 
516     return -1;
517 }
518 
519 /* compatibility wrapper */
520 int inet_parse(InetSocketAddress *addr, const char *str, Error **errp)
521 {
522     const char *optstr, *h;
523     char host[65];
524     char port[33];
525     int to;
526     int pos;
527 
528     memset(addr, 0, sizeof(*addr));
529 
530     /* parse address */
531     if (str[0] == ':') {
532         /* no host given */
533         host[0] = '\0';
534         if (sscanf(str, ":%32[^,]%n", port, &pos) != 1) {
535             error_setg(errp, "error parsing port in address '%s'", str);
536             return -1;
537         }
538     } else if (str[0] == '[') {
539         /* IPv6 addr */
540         if (sscanf(str, "[%64[^]]]:%32[^,]%n", host, port, &pos) != 2) {
541             error_setg(errp, "error parsing IPv6 address '%s'", str);
542             return -1;
543         }
544     } else {
545         /* hostname or IPv4 addr */
546         if (sscanf(str, "%64[^:]:%32[^,]%n", host, port, &pos) != 2) {
547             error_setg(errp, "error parsing address '%s'", str);
548             return -1;
549         }
550     }
551 
552     addr->host = g_strdup(host);
553     addr->port = g_strdup(port);
554 
555     /* parse options */
556     optstr = str + pos;
557     h = strstr(optstr, ",to=");
558     if (h) {
559         h += 4;
560         if (sscanf(h, "%d%n", &to, &pos) != 1 ||
561             (h[pos] != '\0' && h[pos] != ',')) {
562             error_setg(errp, "error parsing to= argument");
563             return -1;
564         }
565         addr->has_to = true;
566         addr->to = to;
567     }
568     if (strstr(optstr, ",ipv4")) {
569         addr->ipv4 = addr->has_ipv4 = true;
570     }
571     if (strstr(optstr, ",ipv6")) {
572         addr->ipv6 = addr->has_ipv6 = true;
573     }
574     return 0;
575 }
576 
577 
578 /**
579  * Create a blocking socket and connect it to an address.
580  *
581  * @str: address string
582  * @errp: set in case of an error
583  *
584  * Returns -1 in case of error, file descriptor on success
585  **/
586 int inet_connect(const char *str, Error **errp)
587 {
588     int sock = -1;
589     InetSocketAddress *addr = g_new(InetSocketAddress, 1);
590 
591     if (!inet_parse(addr, str, errp)) {
592         sock = inet_connect_saddr(addr, errp);
593     }
594     qapi_free_InetSocketAddress(addr);
595     return sock;
596 }
597 
598 #ifdef CONFIG_AF_VSOCK
599 static bool vsock_parse_vaddr_to_sockaddr(const VsockSocketAddress *vaddr,
600                                           struct sockaddr_vm *svm,
601                                           Error **errp)
602 {
603     unsigned long long val;
604 
605     memset(svm, 0, sizeof(*svm));
606     svm->svm_family = AF_VSOCK;
607 
608     if (parse_uint_full(vaddr->cid, &val, 10) < 0 ||
609         val > UINT32_MAX) {
610         error_setg(errp, "Failed to parse cid '%s'", vaddr->cid);
611         return false;
612     }
613     svm->svm_cid = val;
614 
615     if (parse_uint_full(vaddr->port, &val, 10) < 0 ||
616         val > UINT32_MAX) {
617         error_setg(errp, "Failed to parse port '%s'", vaddr->port);
618         return false;
619     }
620     svm->svm_port = val;
621 
622     return true;
623 }
624 
625 static int vsock_connect_addr(const struct sockaddr_vm *svm, Error **errp)
626 {
627     int sock, rc;
628 
629     sock = qemu_socket(AF_VSOCK, SOCK_STREAM, 0);
630     if (sock < 0) {
631         error_setg_errno(errp, errno, "Failed to create socket");
632         return -1;
633     }
634 
635     /* connect to peer */
636     do {
637         rc = 0;
638         if (connect(sock, (const struct sockaddr *)svm, sizeof(*svm)) < 0) {
639             rc = -errno;
640         }
641     } while (rc == -EINTR);
642 
643     if (rc < 0) {
644         error_setg_errno(errp, errno, "Failed to connect socket");
645         closesocket(sock);
646         return -1;
647     }
648 
649     return sock;
650 }
651 
652 static int vsock_connect_saddr(VsockSocketAddress *vaddr, Error **errp)
653 {
654     struct sockaddr_vm svm;
655     int sock = -1;
656 
657     if (!vsock_parse_vaddr_to_sockaddr(vaddr, &svm, errp)) {
658         return -1;
659     }
660 
661     sock = vsock_connect_addr(&svm, errp);
662 
663     return sock;
664 }
665 
666 static int vsock_listen_saddr(VsockSocketAddress *vaddr,
667                               Error **errp)
668 {
669     struct sockaddr_vm svm;
670     int slisten;
671 
672     if (!vsock_parse_vaddr_to_sockaddr(vaddr, &svm, errp)) {
673         return -1;
674     }
675 
676     slisten = qemu_socket(AF_VSOCK, SOCK_STREAM, 0);
677     if (slisten < 0) {
678         error_setg_errno(errp, errno, "Failed to create socket");
679         return -1;
680     }
681 
682     if (bind(slisten, (const struct sockaddr *)&svm, sizeof(svm)) != 0) {
683         error_setg_errno(errp, errno, "Failed to bind socket");
684         closesocket(slisten);
685         return -1;
686     }
687 
688     if (listen(slisten, 1) != 0) {
689         error_setg_errno(errp, errno, "Failed to listen on socket");
690         closesocket(slisten);
691         return -1;
692     }
693     return slisten;
694 }
695 
696 static int vsock_parse(VsockSocketAddress *addr, const char *str,
697                        Error **errp)
698 {
699     char cid[33];
700     char port[33];
701     int n;
702 
703     if (sscanf(str, "%32[^:]:%32[^,]%n", cid, port, &n) != 2) {
704         error_setg(errp, "error parsing address '%s'", str);
705         return -1;
706     }
707     if (str[n] != '\0') {
708         error_setg(errp, "trailing characters in address '%s'", str);
709         return -1;
710     }
711 
712     addr->cid = g_strdup(cid);
713     addr->port = g_strdup(port);
714     return 0;
715 }
716 #else
717 static void vsock_unsupported(Error **errp)
718 {
719     error_setg(errp, "socket family AF_VSOCK unsupported");
720 }
721 
722 static int vsock_connect_saddr(VsockSocketAddress *vaddr, Error **errp)
723 {
724     vsock_unsupported(errp);
725     return -1;
726 }
727 
728 static int vsock_listen_saddr(VsockSocketAddress *vaddr,
729                               Error **errp)
730 {
731     vsock_unsupported(errp);
732     return -1;
733 }
734 
735 static int vsock_parse(VsockSocketAddress *addr, const char *str,
736                         Error **errp)
737 {
738     vsock_unsupported(errp);
739     return -1;
740 }
741 #endif /* CONFIG_AF_VSOCK */
742 
743 #ifndef _WIN32
744 
745 static int unix_listen_saddr(UnixSocketAddress *saddr,
746                              bool update_addr,
747                              Error **errp)
748 {
749     struct sockaddr_un un;
750     int sock, fd;
751     char *pathbuf = NULL;
752     const char *path;
753 
754     sock = qemu_socket(PF_UNIX, SOCK_STREAM, 0);
755     if (sock < 0) {
756         error_setg_errno(errp, errno, "Failed to create Unix socket");
757         return -1;
758     }
759 
760     if (saddr->path && saddr->path[0]) {
761         path = saddr->path;
762     } else {
763         const char *tmpdir = getenv("TMPDIR");
764         tmpdir = tmpdir ? tmpdir : "/tmp";
765         path = pathbuf = g_strdup_printf("%s/qemu-socket-XXXXXX", tmpdir);
766     }
767 
768     if (strlen(path) > sizeof(un.sun_path)) {
769         error_setg(errp, "UNIX socket path '%s' is too long", path);
770         error_append_hint(errp, "Path must be less than %zu bytes\n",
771                           sizeof(un.sun_path));
772         goto err;
773     }
774 
775     if (pathbuf != NULL) {
776         /*
777          * This dummy fd usage silences the mktemp() unsecure warning.
778          * Using mkstemp() doesn't make things more secure here
779          * though.  bind() complains about existing files, so we have
780          * to unlink first and thus re-open the race window.  The
781          * worst case possible is bind() failing, i.e. a DoS attack.
782          */
783         fd = mkstemp(pathbuf);
784         if (fd < 0) {
785             error_setg_errno(errp, errno,
786                              "Failed to make a temporary socket %s", pathbuf);
787             goto err;
788         }
789         close(fd);
790     }
791 
792     if (unlink(path) < 0 && errno != ENOENT) {
793         error_setg_errno(errp, errno,
794                          "Failed to unlink socket %s", path);
795         goto err;
796     }
797 
798     memset(&un, 0, sizeof(un));
799     un.sun_family = AF_UNIX;
800     strncpy(un.sun_path, path, sizeof(un.sun_path));
801 
802     if (bind(sock, (struct sockaddr*) &un, sizeof(un)) < 0) {
803         error_setg_errno(errp, errno, "Failed to bind socket to %s", path);
804         goto err;
805     }
806     if (listen(sock, 1) < 0) {
807         error_setg_errno(errp, errno, "Failed to listen on socket");
808         goto err;
809     }
810 
811     if (update_addr && pathbuf) {
812         g_free(saddr->path);
813         saddr->path = pathbuf;
814     } else {
815         g_free(pathbuf);
816     }
817     return sock;
818 
819 err:
820     g_free(pathbuf);
821     closesocket(sock);
822     return -1;
823 }
824 
825 static int unix_connect_saddr(UnixSocketAddress *saddr, Error **errp)
826 {
827     struct sockaddr_un un;
828     int sock, rc;
829 
830     if (saddr->path == NULL) {
831         error_setg(errp, "unix connect: no path specified");
832         return -1;
833     }
834 
835     sock = qemu_socket(PF_UNIX, SOCK_STREAM, 0);
836     if (sock < 0) {
837         error_setg_errno(errp, errno, "Failed to create socket");
838         return -1;
839     }
840 
841     if (strlen(saddr->path) > sizeof(un.sun_path)) {
842         error_setg(errp, "UNIX socket path '%s' is too long", saddr->path);
843         error_append_hint(errp, "Path must be less than %zu bytes\n",
844                           sizeof(un.sun_path));
845         goto err;
846     }
847 
848     memset(&un, 0, sizeof(un));
849     un.sun_family = AF_UNIX;
850     strncpy(un.sun_path, saddr->path, sizeof(un.sun_path));
851 
852     /* connect to peer */
853     do {
854         rc = 0;
855         if (connect(sock, (struct sockaddr *) &un, sizeof(un)) < 0) {
856             rc = -errno;
857         }
858     } while (rc == -EINTR);
859 
860     if (rc < 0) {
861         error_setg_errno(errp, -rc, "Failed to connect socket %s",
862                          saddr->path);
863         goto err;
864     }
865 
866     return sock;
867 
868  err:
869     close(sock);
870     return -1;
871 }
872 
873 #else
874 
875 static int unix_listen_saddr(UnixSocketAddress *saddr,
876                              bool update_addr,
877                              Error **errp)
878 {
879     error_setg(errp, "unix sockets are not available on windows");
880     errno = ENOTSUP;
881     return -1;
882 }
883 
884 static int unix_connect_saddr(UnixSocketAddress *saddr, Error **errp)
885 {
886     error_setg(errp, "unix sockets are not available on windows");
887     errno = ENOTSUP;
888     return -1;
889 }
890 #endif
891 
892 /* compatibility wrapper */
893 int unix_listen(const char *str, char *ostr, int olen, Error **errp)
894 {
895     char *path, *optstr;
896     int sock, len;
897     UnixSocketAddress *saddr;
898 
899     saddr = g_new0(UnixSocketAddress, 1);
900 
901     optstr = strchr(str, ',');
902     if (optstr) {
903         len = optstr - str;
904         if (len) {
905             path = g_malloc(len+1);
906             snprintf(path, len+1, "%.*s", len, str);
907             saddr->path = path;
908         }
909     } else {
910         saddr->path = g_strdup(str);
911     }
912 
913     sock = unix_listen_saddr(saddr, true, errp);
914 
915     if (sock != -1 && ostr) {
916         snprintf(ostr, olen, "%s%s", saddr->path, optstr ? optstr : "");
917     }
918 
919     qapi_free_UnixSocketAddress(saddr);
920     return sock;
921 }
922 
923 int unix_connect(const char *path, Error **errp)
924 {
925     UnixSocketAddress *saddr;
926     int sock;
927 
928     saddr = g_new0(UnixSocketAddress, 1);
929     saddr->path = g_strdup(path);
930     sock = unix_connect_saddr(saddr, errp);
931     qapi_free_UnixSocketAddress(saddr);
932     return sock;
933 }
934 
935 
936 SocketAddress *socket_parse(const char *str, Error **errp)
937 {
938     SocketAddress *addr;
939 
940     addr = g_new0(SocketAddress, 1);
941     if (strstart(str, "unix:", NULL)) {
942         if (str[5] == '\0') {
943             error_setg(errp, "invalid Unix socket address");
944             goto fail;
945         } else {
946             addr->type = SOCKET_ADDRESS_TYPE_UNIX;
947             addr->u.q_unix.path = g_strdup(str + 5);
948         }
949     } else if (strstart(str, "fd:", NULL)) {
950         if (str[3] == '\0') {
951             error_setg(errp, "invalid file descriptor address");
952             goto fail;
953         } else {
954             addr->type = SOCKET_ADDRESS_TYPE_FD;
955             addr->u.fd.str = g_strdup(str + 3);
956         }
957     } else if (strstart(str, "vsock:", NULL)) {
958         addr->type = SOCKET_ADDRESS_TYPE_VSOCK;
959         if (vsock_parse(&addr->u.vsock, str + strlen("vsock:"), errp)) {
960             goto fail;
961         }
962     } else {
963         addr->type = SOCKET_ADDRESS_TYPE_INET;
964         if (inet_parse(&addr->u.inet, str, errp)) {
965             goto fail;
966         }
967     }
968     return addr;
969 
970 fail:
971     qapi_free_SocketAddress(addr);
972     return NULL;
973 }
974 
975 int socket_connect(SocketAddress *addr, Error **errp)
976 {
977     int fd;
978 
979     switch (addr->type) {
980     case SOCKET_ADDRESS_TYPE_INET:
981         fd = inet_connect_saddr(&addr->u.inet, errp);
982         break;
983 
984     case SOCKET_ADDRESS_TYPE_UNIX:
985         fd = unix_connect_saddr(&addr->u.q_unix, errp);
986         break;
987 
988     case SOCKET_ADDRESS_TYPE_FD:
989         fd = monitor_get_fd(cur_mon, addr->u.fd.str, errp);
990         break;
991 
992     case SOCKET_ADDRESS_TYPE_VSOCK:
993         fd = vsock_connect_saddr(&addr->u.vsock, errp);
994         break;
995 
996     default:
997         abort();
998     }
999     return fd;
1000 }
1001 
1002 int socket_listen(SocketAddress *addr, Error **errp)
1003 {
1004     int fd;
1005 
1006     switch (addr->type) {
1007     case SOCKET_ADDRESS_TYPE_INET:
1008         fd = inet_listen_saddr(&addr->u.inet, 0, false, errp);
1009         break;
1010 
1011     case SOCKET_ADDRESS_TYPE_UNIX:
1012         fd = unix_listen_saddr(&addr->u.q_unix, false, errp);
1013         break;
1014 
1015     case SOCKET_ADDRESS_TYPE_FD:
1016         fd = monitor_get_fd(cur_mon, addr->u.fd.str, errp);
1017         break;
1018 
1019     case SOCKET_ADDRESS_TYPE_VSOCK:
1020         fd = vsock_listen_saddr(&addr->u.vsock, errp);
1021         break;
1022 
1023     default:
1024         abort();
1025     }
1026     return fd;
1027 }
1028 
1029 void socket_listen_cleanup(int fd, Error **errp)
1030 {
1031     SocketAddress *addr;
1032 
1033     addr = socket_local_address(fd, errp);
1034 
1035     if (addr->type == SOCKET_ADDRESS_TYPE_UNIX
1036         && addr->u.q_unix.path) {
1037         if (unlink(addr->u.q_unix.path) < 0 && errno != ENOENT) {
1038             error_setg_errno(errp, errno,
1039                              "Failed to unlink socket %s",
1040                              addr->u.q_unix.path);
1041         }
1042     }
1043 
1044     qapi_free_SocketAddress(addr);
1045 }
1046 
1047 int socket_dgram(SocketAddress *remote, SocketAddress *local, Error **errp)
1048 {
1049     int fd;
1050 
1051     /*
1052      * TODO SOCKET_ADDRESS_TYPE_FD when fd is AF_INET or AF_INET6
1053      * (although other address families can do SOCK_DGRAM, too)
1054      */
1055     switch (remote->type) {
1056     case SOCKET_ADDRESS_TYPE_INET:
1057         fd = inet_dgram_saddr(&remote->u.inet,
1058                               local ? &local->u.inet : NULL, errp);
1059         break;
1060 
1061     default:
1062         error_setg(errp, "socket type unsupported for datagram");
1063         fd = -1;
1064     }
1065     return fd;
1066 }
1067 
1068 
1069 static SocketAddress *
1070 socket_sockaddr_to_address_inet(struct sockaddr_storage *sa,
1071                                 socklen_t salen,
1072                                 Error **errp)
1073 {
1074     char host[NI_MAXHOST];
1075     char serv[NI_MAXSERV];
1076     SocketAddress *addr;
1077     InetSocketAddress *inet;
1078     int ret;
1079 
1080     ret = getnameinfo((struct sockaddr *)sa, salen,
1081                       host, sizeof(host),
1082                       serv, sizeof(serv),
1083                       NI_NUMERICHOST | NI_NUMERICSERV);
1084     if (ret != 0) {
1085         error_setg(errp, "Cannot format numeric socket address: %s",
1086                    gai_strerror(ret));
1087         return NULL;
1088     }
1089 
1090     addr = g_new0(SocketAddress, 1);
1091     addr->type = SOCKET_ADDRESS_TYPE_INET;
1092     inet = &addr->u.inet;
1093     inet->host = g_strdup(host);
1094     inet->port = g_strdup(serv);
1095     if (sa->ss_family == AF_INET) {
1096         inet->has_ipv4 = inet->ipv4 = true;
1097     } else {
1098         inet->has_ipv6 = inet->ipv6 = true;
1099     }
1100 
1101     return addr;
1102 }
1103 
1104 
1105 #ifndef WIN32
1106 static SocketAddress *
1107 socket_sockaddr_to_address_unix(struct sockaddr_storage *sa,
1108                                 socklen_t salen,
1109                                 Error **errp)
1110 {
1111     SocketAddress *addr;
1112     struct sockaddr_un *su = (struct sockaddr_un *)sa;
1113 
1114     addr = g_new0(SocketAddress, 1);
1115     addr->type = SOCKET_ADDRESS_TYPE_UNIX;
1116     if (su->sun_path[0]) {
1117         addr->u.q_unix.path = g_strndup(su->sun_path, sizeof(su->sun_path));
1118     }
1119 
1120     return addr;
1121 }
1122 #endif /* WIN32 */
1123 
1124 #ifdef CONFIG_AF_VSOCK
1125 static SocketAddress *
1126 socket_sockaddr_to_address_vsock(struct sockaddr_storage *sa,
1127                                  socklen_t salen,
1128                                  Error **errp)
1129 {
1130     SocketAddress *addr;
1131     VsockSocketAddress *vaddr;
1132     struct sockaddr_vm *svm = (struct sockaddr_vm *)sa;
1133 
1134     addr = g_new0(SocketAddress, 1);
1135     addr->type = SOCKET_ADDRESS_TYPE_VSOCK;
1136     vaddr = &addr->u.vsock;
1137     vaddr->cid = g_strdup_printf("%u", svm->svm_cid);
1138     vaddr->port = g_strdup_printf("%u", svm->svm_port);
1139 
1140     return addr;
1141 }
1142 #endif /* CONFIG_AF_VSOCK */
1143 
1144 SocketAddress *
1145 socket_sockaddr_to_address(struct sockaddr_storage *sa,
1146                            socklen_t salen,
1147                            Error **errp)
1148 {
1149     switch (sa->ss_family) {
1150     case AF_INET:
1151     case AF_INET6:
1152         return socket_sockaddr_to_address_inet(sa, salen, errp);
1153 
1154 #ifndef WIN32
1155     case AF_UNIX:
1156         return socket_sockaddr_to_address_unix(sa, salen, errp);
1157 #endif /* WIN32 */
1158 
1159 #ifdef CONFIG_AF_VSOCK
1160     case AF_VSOCK:
1161         return socket_sockaddr_to_address_vsock(sa, salen, errp);
1162 #endif
1163 
1164     default:
1165         error_setg(errp, "socket family %d unsupported",
1166                    sa->ss_family);
1167         return NULL;
1168     }
1169     return 0;
1170 }
1171 
1172 
1173 SocketAddress *socket_local_address(int fd, Error **errp)
1174 {
1175     struct sockaddr_storage ss;
1176     socklen_t sslen = sizeof(ss);
1177 
1178     if (getsockname(fd, (struct sockaddr *)&ss, &sslen) < 0) {
1179         error_setg_errno(errp, errno, "%s",
1180                          "Unable to query local socket address");
1181         return NULL;
1182     }
1183 
1184     return socket_sockaddr_to_address(&ss, sslen, errp);
1185 }
1186 
1187 
1188 SocketAddress *socket_remote_address(int fd, Error **errp)
1189 {
1190     struct sockaddr_storage ss;
1191     socklen_t sslen = sizeof(ss);
1192 
1193     if (getpeername(fd, (struct sockaddr *)&ss, &sslen) < 0) {
1194         error_setg_errno(errp, errno, "%s",
1195                          "Unable to query remote socket address");
1196         return NULL;
1197     }
1198 
1199     return socket_sockaddr_to_address(&ss, sslen, errp);
1200 }
1201 
1202 
1203 SocketAddress *socket_address_flatten(SocketAddressLegacy *addr_legacy)
1204 {
1205     SocketAddress *addr;
1206 
1207     if (!addr_legacy) {
1208         return NULL;
1209     }
1210 
1211     addr = g_new(SocketAddress, 1);
1212 
1213     switch (addr_legacy->type) {
1214     case SOCKET_ADDRESS_LEGACY_KIND_INET:
1215         addr->type = SOCKET_ADDRESS_TYPE_INET;
1216         QAPI_CLONE_MEMBERS(InetSocketAddress, &addr->u.inet,
1217                            addr_legacy->u.inet.data);
1218         break;
1219     case SOCKET_ADDRESS_LEGACY_KIND_UNIX:
1220         addr->type = SOCKET_ADDRESS_TYPE_UNIX;
1221         QAPI_CLONE_MEMBERS(UnixSocketAddress, &addr->u.q_unix,
1222                            addr_legacy->u.q_unix.data);
1223         break;
1224     case SOCKET_ADDRESS_LEGACY_KIND_VSOCK:
1225         addr->type = SOCKET_ADDRESS_TYPE_VSOCK;
1226         QAPI_CLONE_MEMBERS(VsockSocketAddress, &addr->u.vsock,
1227                            addr_legacy->u.vsock.data);
1228         break;
1229     case SOCKET_ADDRESS_LEGACY_KIND_FD:
1230         addr->type = SOCKET_ADDRESS_TYPE_FD;
1231         QAPI_CLONE_MEMBERS(String, &addr->u.fd, addr_legacy->u.fd.data);
1232         break;
1233     default:
1234         abort();
1235     }
1236 
1237     return addr;
1238 }
1239