xref: /openbmc/qemu/util/qemu-sockets.c (revision ff0102f6)
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 "qapi/qapi-visit-sockets.h"
28 #include "qemu/sockets.h"
29 #include "qemu/main-loop.h"
30 #include "qapi/qobject-input-visitor.h"
31 #include "qapi/qobject-output-visitor.h"
32 #include "qemu/cutils.h"
33 #include "trace.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 !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         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                              int num,
211                              Error **errp)
212 {
213     struct addrinfo ai,*res,*e;
214     char port[33];
215     char uaddr[INET6_ADDRSTRLEN+1];
216     char uport[33];
217     int rc, port_min, port_max, p;
218     int slisten = -1;
219     int saved_errno = 0;
220     bool socket_created = false;
221     Error *err = NULL;
222 
223     if (saddr->keep_alive) {
224         error_setg(errp, "keep-alive option is not supported for passive "
225                    "sockets");
226         return -1;
227     }
228 
229     memset(&ai,0, sizeof(ai));
230     ai.ai_flags = AI_PASSIVE;
231     if (saddr->has_numeric && saddr->numeric) {
232         ai.ai_flags |= AI_NUMERICHOST | AI_NUMERICSERV;
233     }
234     ai.ai_family = inet_ai_family_from_address(saddr, &err);
235     ai.ai_socktype = SOCK_STREAM;
236 
237     if (err) {
238         error_propagate(errp, err);
239         return -1;
240     }
241 
242     if (saddr->host == NULL) {
243         error_setg(errp, "host not specified");
244         return -1;
245     }
246     if (saddr->port != NULL) {
247         pstrcpy(port, sizeof(port), saddr->port);
248     } else {
249         port[0] = '\0';
250     }
251 
252     /* lookup */
253     if (port_offset) {
254         unsigned long long baseport;
255         if (strlen(port) == 0) {
256             error_setg(errp, "port not specified");
257             return -1;
258         }
259         if (parse_uint_full(port, &baseport, 10) < 0) {
260             error_setg(errp, "can't convert to a number: %s", port);
261             return -1;
262         }
263         if (baseport > 65535 ||
264             baseport + port_offset > 65535) {
265             error_setg(errp, "port %s out of range", port);
266             return -1;
267         }
268         snprintf(port, sizeof(port), "%d", (int)baseport + port_offset);
269     }
270     rc = getaddrinfo(strlen(saddr->host) ? saddr->host : NULL,
271                      strlen(port) ? port : NULL, &ai, &res);
272     if (rc != 0) {
273         error_setg(errp, "address resolution failed for %s:%s: %s",
274                    saddr->host, port, gai_strerror(rc));
275         return -1;
276     }
277 
278     /* create socket + bind/listen */
279     for (e = res; e != NULL; e = e->ai_next) {
280 #ifdef HAVE_IPPROTO_MPTCP
281         if (saddr->has_mptcp && saddr->mptcp) {
282             e->ai_protocol = IPPROTO_MPTCP;
283         }
284 #endif
285         getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,
286                         uaddr,INET6_ADDRSTRLEN,uport,32,
287                         NI_NUMERICHOST | NI_NUMERICSERV);
288 
289         port_min = inet_getport(e);
290         port_max = saddr->has_to ? saddr->to + port_offset : port_min;
291         for (p = port_min; p <= port_max; p++) {
292             inet_setport(e, p);
293 
294             slisten = create_fast_reuse_socket(e);
295             if (slisten < 0) {
296                 /* First time we expect we might fail to create the socket
297                  * eg if 'e' has AF_INET6 but ipv6 kmod is not loaded.
298                  * Later iterations should always succeed if first iteration
299                  * worked though, so treat that as fatal.
300                  */
301                 if (p == port_min) {
302                     continue;
303                 } else {
304                     error_setg_errno(errp, errno,
305                                      "Failed to recreate failed listening socket");
306                     goto listen_failed;
307                 }
308             }
309             socket_created = true;
310 
311             rc = try_bind(slisten, saddr, e);
312             if (rc < 0) {
313                 if (errno != EADDRINUSE) {
314                     error_setg_errno(errp, errno, "Failed to bind socket");
315                     goto listen_failed;
316                 }
317             } else {
318                 if (!listen(slisten, num)) {
319                     goto listen_ok;
320                 }
321                 if (errno != EADDRINUSE) {
322                     error_setg_errno(errp, errno, "Failed to listen on socket");
323                     goto listen_failed;
324                 }
325             }
326             /* Someone else managed to bind to the same port and beat us
327              * to listen on it! Socket semantics does not allow us to
328              * recover from this situation, so we need to recreate the
329              * socket to allow bind attempts for subsequent ports:
330              */
331             closesocket(slisten);
332             slisten = -1;
333         }
334     }
335     error_setg_errno(errp, errno,
336                      socket_created ?
337                      "Failed to find an available port" :
338                      "Failed to create a socket");
339 listen_failed:
340     saved_errno = errno;
341     if (slisten >= 0) {
342         closesocket(slisten);
343     }
344     freeaddrinfo(res);
345     errno = saved_errno;
346     return -1;
347 
348 listen_ok:
349     freeaddrinfo(res);
350     return slisten;
351 }
352 
353 #ifdef _WIN32
354 #define QEMU_SOCKET_RC_INPROGRESS(rc) \
355     ((rc) == -EINPROGRESS || (rc) == -EWOULDBLOCK || (rc) == -WSAEALREADY)
356 #else
357 #define QEMU_SOCKET_RC_INPROGRESS(rc) \
358     ((rc) == -EINPROGRESS)
359 #endif
360 
361 static int inet_connect_addr(const InetSocketAddress *saddr,
362                              struct addrinfo *addr, Error **errp)
363 {
364     int sock, rc;
365 
366     sock = qemu_socket(addr->ai_family, addr->ai_socktype, addr->ai_protocol);
367     if (sock < 0) {
368         error_setg_errno(errp, errno, "Failed to create socket family %d",
369                          addr->ai_family);
370         return -1;
371     }
372     socket_set_fast_reuse(sock);
373 
374     /* connect to peer */
375     do {
376         rc = 0;
377         if (connect(sock, addr->ai_addr, addr->ai_addrlen) < 0) {
378             rc = -errno;
379         }
380     } while (rc == -EINTR);
381 
382     if (rc < 0) {
383         error_setg_errno(errp, errno, "Failed to connect to '%s:%s'",
384                          saddr->host, saddr->port);
385         closesocket(sock);
386         return -1;
387     }
388 
389     return sock;
390 }
391 
392 static struct addrinfo *inet_parse_connect_saddr(InetSocketAddress *saddr,
393                                                  Error **errp)
394 {
395     struct addrinfo ai, *res;
396     int rc;
397     Error *err = NULL;
398     static int useV4Mapped = 1;
399 
400     memset(&ai, 0, sizeof(ai));
401 
402     ai.ai_flags = AI_CANONNAME | AI_ADDRCONFIG;
403     if (qatomic_read(&useV4Mapped)) {
404         ai.ai_flags |= AI_V4MAPPED;
405     }
406     ai.ai_family = inet_ai_family_from_address(saddr, &err);
407     ai.ai_socktype = SOCK_STREAM;
408 
409     if (err) {
410         error_propagate(errp, err);
411         return NULL;
412     }
413 
414     if (saddr->host == NULL || saddr->port == NULL) {
415         error_setg(errp, "host and/or port not specified");
416         return NULL;
417     }
418 
419     /* lookup */
420     rc = getaddrinfo(saddr->host, saddr->port, &ai, &res);
421 
422     /* At least FreeBSD and OS-X 10.6 declare AI_V4MAPPED but
423      * then don't implement it in their getaddrinfo(). Detect
424      * this and retry without the flag since that's preferable
425      * to a fatal error
426      */
427     if (rc == EAI_BADFLAGS &&
428         (ai.ai_flags & AI_V4MAPPED)) {
429         qatomic_set(&useV4Mapped, 0);
430         ai.ai_flags &= ~AI_V4MAPPED;
431         rc = getaddrinfo(saddr->host, saddr->port, &ai, &res);
432     }
433     if (rc != 0) {
434         error_setg(errp, "address resolution failed for %s:%s: %s",
435                    saddr->host, saddr->port, gai_strerror(rc));
436         return NULL;
437     }
438     return res;
439 }
440 
441 /**
442  * Create a socket and connect it to an address.
443  *
444  * @saddr: Inet socket address specification
445  * @errp: set on error
446  *
447  * Returns: -1 on error, file descriptor on success.
448  */
449 int inet_connect_saddr(InetSocketAddress *saddr, Error **errp)
450 {
451     Error *local_err = NULL;
452     struct addrinfo *res, *e;
453     int sock = -1;
454 
455     res = inet_parse_connect_saddr(saddr, errp);
456     if (!res) {
457         return -1;
458     }
459 
460     for (e = res; e != NULL; e = e->ai_next) {
461         error_free(local_err);
462         local_err = NULL;
463 
464 #ifdef HAVE_IPPROTO_MPTCP
465         if (saddr->has_mptcp && saddr->mptcp) {
466             e->ai_protocol = IPPROTO_MPTCP;
467         }
468 #endif
469 
470         sock = inet_connect_addr(saddr, e, &local_err);
471         if (sock >= 0) {
472             break;
473         }
474     }
475 
476     freeaddrinfo(res);
477 
478     if (sock < 0) {
479         error_propagate(errp, local_err);
480         return sock;
481     }
482 
483     if (saddr->keep_alive) {
484         int val = 1;
485         int ret = setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
486                              &val, sizeof(val));
487 
488         if (ret < 0) {
489             error_setg_errno(errp, errno, "Unable to set KEEPALIVE");
490             closesocket(sock);
491             return -1;
492         }
493     }
494 
495     return sock;
496 }
497 
498 static int inet_dgram_saddr(InetSocketAddress *sraddr,
499                             InetSocketAddress *sladdr,
500                             Error **errp)
501 {
502     struct addrinfo ai, *peer = NULL, *local = NULL;
503     const char *addr;
504     const char *port;
505     int sock = -1, rc;
506     Error *err = NULL;
507 
508     /* lookup peer addr */
509     memset(&ai,0, sizeof(ai));
510     ai.ai_flags = AI_CANONNAME | AI_V4MAPPED | AI_ADDRCONFIG;
511     ai.ai_family = inet_ai_family_from_address(sraddr, &err);
512     ai.ai_socktype = SOCK_DGRAM;
513 
514     if (err) {
515         error_propagate(errp, err);
516         goto err;
517     }
518 
519     addr = sraddr->host;
520     port = sraddr->port;
521     if (addr == NULL || strlen(addr) == 0) {
522         addr = "localhost";
523     }
524     if (port == NULL || strlen(port) == 0) {
525         error_setg(errp, "remote port not specified");
526         goto err;
527     }
528 
529     if ((rc = getaddrinfo(addr, port, &ai, &peer)) != 0) {
530         error_setg(errp, "address resolution failed for %s:%s: %s", addr, port,
531                    gai_strerror(rc));
532         goto err;
533     }
534 
535     /* lookup local addr */
536     memset(&ai,0, sizeof(ai));
537     ai.ai_flags = AI_PASSIVE;
538     ai.ai_family = peer->ai_family;
539     ai.ai_socktype = SOCK_DGRAM;
540 
541     if (sladdr) {
542         addr = sladdr->host;
543         port = sladdr->port;
544         if (addr == NULL || strlen(addr) == 0) {
545             addr = NULL;
546         }
547         if (!port || strlen(port) == 0) {
548             port = "0";
549         }
550     } else {
551         addr = NULL;
552         port = "0";
553     }
554 
555     if ((rc = getaddrinfo(addr, port, &ai, &local)) != 0) {
556         error_setg(errp, "address resolution failed for %s:%s: %s", addr, port,
557                    gai_strerror(rc));
558         goto err;
559     }
560 
561     /* create socket */
562     sock = qemu_socket(peer->ai_family, peer->ai_socktype, peer->ai_protocol);
563     if (sock < 0) {
564         error_setg_errno(errp, errno, "Failed to create socket family %d",
565                          peer->ai_family);
566         goto err;
567     }
568     socket_set_fast_reuse(sock);
569 
570     /* bind socket */
571     if (bind(sock, local->ai_addr, local->ai_addrlen) < 0) {
572         error_setg_errno(errp, errno, "Failed to bind socket");
573         goto err;
574     }
575 
576     /* connect to peer */
577     if (connect(sock,peer->ai_addr,peer->ai_addrlen) < 0) {
578         error_setg_errno(errp, errno, "Failed to connect to '%s:%s'",
579                          addr, port);
580         goto err;
581     }
582 
583     freeaddrinfo(local);
584     freeaddrinfo(peer);
585     return sock;
586 
587 err:
588     if (sock != -1) {
589         closesocket(sock);
590     }
591     if (local) {
592         freeaddrinfo(local);
593     }
594     if (peer) {
595         freeaddrinfo(peer);
596     }
597 
598     return -1;
599 }
600 
601 /* compatibility wrapper */
602 static int inet_parse_flag(const char *flagname, const char *optstr, bool *val,
603                            Error **errp)
604 {
605     char *end;
606     size_t len;
607 
608     end = strstr(optstr, ",");
609     if (end) {
610         if (end[1] == ',') { /* Reject 'ipv6=on,,foo' */
611             error_setg(errp, "error parsing '%s' flag '%s'", flagname, optstr);
612             return -1;
613         }
614         len = end - optstr;
615     } else {
616         len = strlen(optstr);
617     }
618     if (len == 0 || (len == 3 && strncmp(optstr, "=on", len) == 0)) {
619         *val = true;
620     } else if (len == 4 && strncmp(optstr, "=off", len) == 0) {
621         *val = false;
622     } else {
623         error_setg(errp, "error parsing '%s' flag '%s'", flagname, optstr);
624         return -1;
625     }
626     return 0;
627 }
628 
629 int inet_parse(InetSocketAddress *addr, const char *str, Error **errp)
630 {
631     const char *optstr, *h;
632     char host[65];
633     char port[33];
634     int to;
635     int pos;
636     char *begin;
637 
638     memset(addr, 0, sizeof(*addr));
639 
640     /* parse address */
641     if (str[0] == ':') {
642         /* no host given */
643         host[0] = '\0';
644         if (sscanf(str, ":%32[^,]%n", port, &pos) != 1) {
645             error_setg(errp, "error parsing port in address '%s'", str);
646             return -1;
647         }
648     } else if (str[0] == '[') {
649         /* IPv6 addr */
650         if (sscanf(str, "[%64[^]]]:%32[^,]%n", host, port, &pos) != 2) {
651             error_setg(errp, "error parsing IPv6 address '%s'", str);
652             return -1;
653         }
654     } else {
655         /* hostname or IPv4 addr */
656         if (sscanf(str, "%64[^:]:%32[^,]%n", host, port, &pos) != 2) {
657             error_setg(errp, "error parsing address '%s'", str);
658             return -1;
659         }
660     }
661 
662     addr->host = g_strdup(host);
663     addr->port = g_strdup(port);
664 
665     /* parse options */
666     optstr = str + pos;
667     h = strstr(optstr, ",to=");
668     if (h) {
669         h += 4;
670         if (sscanf(h, "%d%n", &to, &pos) != 1 ||
671             (h[pos] != '\0' && h[pos] != ',')) {
672             error_setg(errp, "error parsing to= argument");
673             return -1;
674         }
675         addr->has_to = true;
676         addr->to = to;
677     }
678     begin = strstr(optstr, ",ipv4");
679     if (begin) {
680         if (inet_parse_flag("ipv4", begin + 5, &addr->ipv4, errp) < 0) {
681             return -1;
682         }
683         addr->has_ipv4 = true;
684     }
685     begin = strstr(optstr, ",ipv6");
686     if (begin) {
687         if (inet_parse_flag("ipv6", begin + 5, &addr->ipv6, errp) < 0) {
688             return -1;
689         }
690         addr->has_ipv6 = true;
691     }
692     begin = strstr(optstr, ",keep-alive");
693     if (begin) {
694         if (inet_parse_flag("keep-alive", begin + strlen(",keep-alive"),
695                             &addr->keep_alive, errp) < 0)
696         {
697             return -1;
698         }
699         addr->has_keep_alive = true;
700     }
701 #ifdef HAVE_IPPROTO_MPTCP
702     begin = strstr(optstr, ",mptcp");
703     if (begin) {
704         if (inet_parse_flag("mptcp", begin + strlen(",mptcp"),
705                             &addr->mptcp, errp) < 0)
706         {
707             return -1;
708         }
709         addr->has_mptcp = true;
710     }
711 #endif
712     return 0;
713 }
714 
715 
716 /**
717  * Create a blocking socket and connect it to an address.
718  *
719  * @str: address string
720  * @errp: set in case of an error
721  *
722  * Returns -1 in case of error, file descriptor on success
723  **/
724 int inet_connect(const char *str, Error **errp)
725 {
726     int sock = -1;
727     InetSocketAddress *addr = g_new(InetSocketAddress, 1);
728 
729     if (!inet_parse(addr, str, errp)) {
730         sock = inet_connect_saddr(addr, errp);
731     }
732     qapi_free_InetSocketAddress(addr);
733     return sock;
734 }
735 
736 #ifdef CONFIG_AF_VSOCK
737 static bool vsock_parse_vaddr_to_sockaddr(const VsockSocketAddress *vaddr,
738                                           struct sockaddr_vm *svm,
739                                           Error **errp)
740 {
741     unsigned long long val;
742 
743     memset(svm, 0, sizeof(*svm));
744     svm->svm_family = AF_VSOCK;
745 
746     if (parse_uint_full(vaddr->cid, &val, 10) < 0 ||
747         val > UINT32_MAX) {
748         error_setg(errp, "Failed to parse cid '%s'", vaddr->cid);
749         return false;
750     }
751     svm->svm_cid = val;
752 
753     if (parse_uint_full(vaddr->port, &val, 10) < 0 ||
754         val > UINT32_MAX) {
755         error_setg(errp, "Failed to parse port '%s'", vaddr->port);
756         return false;
757     }
758     svm->svm_port = val;
759 
760     return true;
761 }
762 
763 static int vsock_connect_addr(const VsockSocketAddress *vaddr,
764                               const struct sockaddr_vm *svm, Error **errp)
765 {
766     int sock, rc;
767 
768     sock = qemu_socket(AF_VSOCK, SOCK_STREAM, 0);
769     if (sock < 0) {
770         error_setg_errno(errp, errno, "Failed to create socket family %d",
771                          AF_VSOCK);
772         return -1;
773     }
774 
775     /* connect to peer */
776     do {
777         rc = 0;
778         if (connect(sock, (const struct sockaddr *)svm, sizeof(*svm)) < 0) {
779             rc = -errno;
780         }
781     } while (rc == -EINTR);
782 
783     if (rc < 0) {
784         error_setg_errno(errp, errno, "Failed to connect to '%s:%s'",
785                          vaddr->cid, vaddr->port);
786         closesocket(sock);
787         return -1;
788     }
789 
790     return sock;
791 }
792 
793 static int vsock_connect_saddr(VsockSocketAddress *vaddr, Error **errp)
794 {
795     struct sockaddr_vm svm;
796 
797     if (!vsock_parse_vaddr_to_sockaddr(vaddr, &svm, errp)) {
798         return -1;
799     }
800 
801     return vsock_connect_addr(vaddr, &svm, errp);
802 }
803 
804 static int vsock_listen_saddr(VsockSocketAddress *vaddr,
805                               int num,
806                               Error **errp)
807 {
808     struct sockaddr_vm svm;
809     int slisten;
810 
811     if (!vsock_parse_vaddr_to_sockaddr(vaddr, &svm, errp)) {
812         return -1;
813     }
814 
815     slisten = qemu_socket(AF_VSOCK, SOCK_STREAM, 0);
816     if (slisten < 0) {
817         error_setg_errno(errp, errno, "Failed to create socket");
818         return -1;
819     }
820 
821     if (bind(slisten, (const struct sockaddr *)&svm, sizeof(svm)) != 0) {
822         error_setg_errno(errp, errno, "Failed to bind socket");
823         closesocket(slisten);
824         return -1;
825     }
826 
827     if (listen(slisten, num) != 0) {
828         error_setg_errno(errp, errno, "Failed to listen on socket");
829         closesocket(slisten);
830         return -1;
831     }
832     return slisten;
833 }
834 
835 static int vsock_parse(VsockSocketAddress *addr, const char *str,
836                        Error **errp)
837 {
838     char cid[33];
839     char port[33];
840     int n;
841 
842     if (sscanf(str, "%32[^:]:%32[^,]%n", cid, port, &n) != 2) {
843         error_setg(errp, "error parsing address '%s'", str);
844         return -1;
845     }
846     if (str[n] != '\0') {
847         error_setg(errp, "trailing characters in address '%s'", str);
848         return -1;
849     }
850 
851     addr->cid = g_strdup(cid);
852     addr->port = g_strdup(port);
853     return 0;
854 }
855 #else
856 static void vsock_unsupported(Error **errp)
857 {
858     error_setg(errp, "socket family AF_VSOCK unsupported");
859 }
860 
861 static int vsock_connect_saddr(VsockSocketAddress *vaddr, Error **errp)
862 {
863     vsock_unsupported(errp);
864     return -1;
865 }
866 
867 static int vsock_listen_saddr(VsockSocketAddress *vaddr,
868                               int num,
869                               Error **errp)
870 {
871     vsock_unsupported(errp);
872     return -1;
873 }
874 
875 static int vsock_parse(VsockSocketAddress *addr, const char *str,
876                         Error **errp)
877 {
878     vsock_unsupported(errp);
879     return -1;
880 }
881 #endif /* CONFIG_AF_VSOCK */
882 
883 static bool saddr_is_abstract(UnixSocketAddress *saddr)
884 {
885 #ifdef CONFIG_LINUX
886     return saddr->abstract;
887 #else
888     return false;
889 #endif
890 }
891 
892 static bool saddr_is_tight(UnixSocketAddress *saddr)
893 {
894 #ifdef CONFIG_LINUX
895     return !saddr->has_tight || saddr->tight;
896 #else
897     return false;
898 #endif
899 }
900 
901 static int unix_listen_saddr(UnixSocketAddress *saddr,
902                              int num,
903                              Error **errp)
904 {
905     bool abstract = saddr_is_abstract(saddr);
906     struct sockaddr_un un;
907     int sock, fd;
908     char *pathbuf = NULL;
909     const char *path;
910     size_t pathlen;
911     size_t addrlen;
912 
913     sock = qemu_socket(PF_UNIX, SOCK_STREAM, 0);
914     if (sock < 0) {
915         error_setg_errno(errp, errno, "Failed to create Unix socket");
916         return -1;
917     }
918 
919     if (saddr->path[0] || abstract) {
920         path = saddr->path;
921     } else {
922         const char *tmpdir = getenv("TMPDIR");
923         tmpdir = tmpdir ? tmpdir : "/tmp";
924         path = pathbuf = g_strdup_printf("%s/qemu-socket-XXXXXX", tmpdir);
925     }
926 
927     pathlen = strlen(path);
928     if (pathlen > sizeof(un.sun_path) ||
929         (abstract && pathlen > (sizeof(un.sun_path) - 1))) {
930         error_setg(errp, "UNIX socket path '%s' is too long", path);
931         error_append_hint(errp, "Path must be less than %zu bytes\n",
932                           abstract ? sizeof(un.sun_path) - 1 :
933                           sizeof(un.sun_path));
934         goto err;
935     }
936 
937     if (pathbuf != NULL) {
938         /*
939          * This dummy fd usage silences the mktemp() unsecure warning.
940          * Using mkstemp() doesn't make things more secure here
941          * though.  bind() complains about existing files, so we have
942          * to unlink first and thus re-open the race window.  The
943          * worst case possible is bind() failing, i.e. a DoS attack.
944          */
945         fd = mkstemp(pathbuf);
946         if (fd < 0) {
947             error_setg_errno(errp, errno,
948                              "Failed to make a temporary socket %s", pathbuf);
949             goto err;
950         }
951         close(fd);
952     }
953 
954     if (!abstract && unlink(path) < 0 && errno != ENOENT) {
955         error_setg_errno(errp, errno,
956                          "Failed to unlink socket %s", path);
957         goto err;
958     }
959 
960     memset(&un, 0, sizeof(un));
961     un.sun_family = AF_UNIX;
962     addrlen = sizeof(un);
963 
964     if (abstract) {
965         un.sun_path[0] = '\0';
966         memcpy(&un.sun_path[1], path, pathlen);
967         if (saddr_is_tight(saddr)) {
968             addrlen = offsetof(struct sockaddr_un, sun_path) + 1 + pathlen;
969         }
970     } else {
971         memcpy(un.sun_path, path, pathlen);
972     }
973 
974     if (bind(sock, (struct sockaddr *) &un, addrlen) < 0) {
975         error_setg_errno(errp, errno, "Failed to bind socket to %s", path);
976         goto err;
977     }
978     if (listen(sock, num) < 0) {
979         error_setg_errno(errp, errno, "Failed to listen on socket");
980         goto err;
981     }
982 
983     g_free(pathbuf);
984     return sock;
985 
986 err:
987     g_free(pathbuf);
988     closesocket(sock);
989     return -1;
990 }
991 
992 static int unix_connect_saddr(UnixSocketAddress *saddr, Error **errp)
993 {
994     bool abstract = saddr_is_abstract(saddr);
995     struct sockaddr_un un;
996     int sock, rc;
997     size_t pathlen;
998     size_t addrlen;
999 
1000     if (saddr->path == NULL) {
1001         error_setg(errp, "unix connect: no path specified");
1002         return -1;
1003     }
1004 
1005     sock = qemu_socket(PF_UNIX, SOCK_STREAM, 0);
1006     if (sock < 0) {
1007         error_setg_errno(errp, errno, "Failed to create socket");
1008         return -1;
1009     }
1010 
1011     pathlen = strlen(saddr->path);
1012     if (pathlen > sizeof(un.sun_path) ||
1013         (abstract && pathlen > (sizeof(un.sun_path) - 1))) {
1014         error_setg(errp, "UNIX socket path '%s' is too long", saddr->path);
1015         error_append_hint(errp, "Path must be less than %zu bytes\n",
1016                           abstract ? sizeof(un.sun_path) - 1 :
1017                           sizeof(un.sun_path));
1018         goto err;
1019     }
1020 
1021     memset(&un, 0, sizeof(un));
1022     un.sun_family = AF_UNIX;
1023     addrlen = sizeof(un);
1024 
1025     if (abstract) {
1026         un.sun_path[0] = '\0';
1027         memcpy(&un.sun_path[1], saddr->path, pathlen);
1028         if (saddr_is_tight(saddr)) {
1029             addrlen = offsetof(struct sockaddr_un, sun_path) + 1 + pathlen;
1030         }
1031     } else {
1032         memcpy(un.sun_path, saddr->path, pathlen);
1033     }
1034     /* connect to peer */
1035     do {
1036         rc = 0;
1037         if (connect(sock, (struct sockaddr *) &un, addrlen) < 0) {
1038             rc = -errno;
1039         }
1040     } while (rc == -EINTR);
1041 
1042     if (rc < 0) {
1043         error_setg_errno(errp, -rc, "Failed to connect to '%s'",
1044                          saddr->path);
1045         goto err;
1046     }
1047 
1048     return sock;
1049 
1050  err:
1051     closesocket(sock);
1052     return -1;
1053 }
1054 
1055 /* compatibility wrapper */
1056 int unix_listen(const char *str, Error **errp)
1057 {
1058     UnixSocketAddress *saddr;
1059     int sock;
1060 
1061     saddr = g_new0(UnixSocketAddress, 1);
1062     saddr->path = g_strdup(str);
1063     sock = unix_listen_saddr(saddr, 1, errp);
1064     qapi_free_UnixSocketAddress(saddr);
1065     return sock;
1066 }
1067 
1068 int unix_connect(const char *path, Error **errp)
1069 {
1070     UnixSocketAddress *saddr;
1071     int sock;
1072 
1073     saddr = g_new0(UnixSocketAddress, 1);
1074     saddr->path = g_strdup(path);
1075     sock = unix_connect_saddr(saddr, errp);
1076     qapi_free_UnixSocketAddress(saddr);
1077     return sock;
1078 }
1079 
1080 
1081 SocketAddress *socket_parse(const char *str, Error **errp)
1082 {
1083     SocketAddress *addr;
1084 
1085     addr = g_new0(SocketAddress, 1);
1086     if (strstart(str, "unix:", NULL)) {
1087         if (str[5] == '\0') {
1088             error_setg(errp, "invalid Unix socket address");
1089             goto fail;
1090         } else {
1091             addr->type = SOCKET_ADDRESS_TYPE_UNIX;
1092             addr->u.q_unix.path = g_strdup(str + 5);
1093         }
1094     } else if (strstart(str, "fd:", NULL)) {
1095         if (str[3] == '\0') {
1096             error_setg(errp, "invalid file descriptor address");
1097             goto fail;
1098         } else {
1099             addr->type = SOCKET_ADDRESS_TYPE_FD;
1100             addr->u.fd.str = g_strdup(str + 3);
1101         }
1102     } else if (strstart(str, "vsock:", NULL)) {
1103         addr->type = SOCKET_ADDRESS_TYPE_VSOCK;
1104         if (vsock_parse(&addr->u.vsock, str + strlen("vsock:"), errp)) {
1105             goto fail;
1106         }
1107     } else {
1108         addr->type = SOCKET_ADDRESS_TYPE_INET;
1109         if (inet_parse(&addr->u.inet, str, errp)) {
1110             goto fail;
1111         }
1112     }
1113     return addr;
1114 
1115 fail:
1116     qapi_free_SocketAddress(addr);
1117     return NULL;
1118 }
1119 
1120 static int socket_get_fd(const char *fdstr, Error **errp)
1121 {
1122     Monitor *cur_mon = monitor_cur();
1123     int fd;
1124     if (cur_mon) {
1125         fd = monitor_get_fd(cur_mon, fdstr, errp);
1126         if (fd < 0) {
1127             return -1;
1128         }
1129     } else {
1130         if (qemu_strtoi(fdstr, NULL, 10, &fd) < 0) {
1131             error_setg_errno(errp, errno,
1132                              "Unable to parse FD number %s",
1133                              fdstr);
1134             return -1;
1135         }
1136     }
1137     if (!fd_is_socket(fd)) {
1138         error_setg(errp, "File descriptor '%s' is not a socket", fdstr);
1139         close(fd);
1140         return -1;
1141     }
1142     return fd;
1143 }
1144 
1145 int socket_address_parse_named_fd(SocketAddress *addr, Error **errp)
1146 {
1147     int fd;
1148 
1149     if (addr->type != SOCKET_ADDRESS_TYPE_FD) {
1150         return 0;
1151     }
1152 
1153     fd = socket_get_fd(addr->u.fd.str, errp);
1154     if (fd < 0) {
1155         return fd;
1156     }
1157 
1158     g_free(addr->u.fd.str);
1159     addr->u.fd.str = g_strdup_printf("%d", fd);
1160 
1161     return 0;
1162 }
1163 
1164 int socket_connect(SocketAddress *addr, Error **errp)
1165 {
1166     int fd;
1167 
1168     switch (addr->type) {
1169     case SOCKET_ADDRESS_TYPE_INET:
1170         fd = inet_connect_saddr(&addr->u.inet, errp);
1171         break;
1172 
1173     case SOCKET_ADDRESS_TYPE_UNIX:
1174         fd = unix_connect_saddr(&addr->u.q_unix, errp);
1175         break;
1176 
1177     case SOCKET_ADDRESS_TYPE_FD:
1178         fd = socket_get_fd(addr->u.fd.str, errp);
1179         break;
1180 
1181     case SOCKET_ADDRESS_TYPE_VSOCK:
1182         fd = vsock_connect_saddr(&addr->u.vsock, errp);
1183         break;
1184 
1185     default:
1186         abort();
1187     }
1188     return fd;
1189 }
1190 
1191 int socket_listen(SocketAddress *addr, int num, Error **errp)
1192 {
1193     int fd;
1194 
1195     trace_socket_listen(num);
1196     switch (addr->type) {
1197     case SOCKET_ADDRESS_TYPE_INET:
1198         fd = inet_listen_saddr(&addr->u.inet, 0, num, errp);
1199         break;
1200 
1201     case SOCKET_ADDRESS_TYPE_UNIX:
1202         fd = unix_listen_saddr(&addr->u.q_unix, num, errp);
1203         break;
1204 
1205     case SOCKET_ADDRESS_TYPE_FD:
1206         fd = socket_get_fd(addr->u.fd.str, errp);
1207         if (fd < 0) {
1208             return -1;
1209         }
1210 
1211         /*
1212          * If the socket is not yet in the listen state, then transition it to
1213          * the listen state now.
1214          *
1215          * If it's already listening then this updates the backlog value as
1216          * requested.
1217          *
1218          * If this socket cannot listen because it's already in another state
1219          * (e.g. unbound or connected) then we'll catch the error here.
1220          */
1221         if (listen(fd, num) != 0) {
1222             error_setg_errno(errp, errno, "Failed to listen on fd socket");
1223             closesocket(fd);
1224             return -1;
1225         }
1226         break;
1227 
1228     case SOCKET_ADDRESS_TYPE_VSOCK:
1229         fd = vsock_listen_saddr(&addr->u.vsock, num, errp);
1230         break;
1231 
1232     default:
1233         abort();
1234     }
1235     return fd;
1236 }
1237 
1238 void socket_listen_cleanup(int fd, Error **errp)
1239 {
1240     SocketAddress *addr;
1241 
1242     addr = socket_local_address(fd, errp);
1243     if (!addr) {
1244         return;
1245     }
1246 
1247     if (addr->type == SOCKET_ADDRESS_TYPE_UNIX
1248         && addr->u.q_unix.path) {
1249         if (unlink(addr->u.q_unix.path) < 0 && errno != ENOENT) {
1250             error_setg_errno(errp, errno,
1251                              "Failed to unlink socket %s",
1252                              addr->u.q_unix.path);
1253         }
1254     }
1255 
1256     qapi_free_SocketAddress(addr);
1257 }
1258 
1259 int socket_dgram(SocketAddress *remote, SocketAddress *local, Error **errp)
1260 {
1261     int fd;
1262 
1263     /*
1264      * TODO SOCKET_ADDRESS_TYPE_FD when fd is AF_INET or AF_INET6
1265      * (although other address families can do SOCK_DGRAM, too)
1266      */
1267     switch (remote->type) {
1268     case SOCKET_ADDRESS_TYPE_INET:
1269         fd = inet_dgram_saddr(&remote->u.inet,
1270                               local ? &local->u.inet : NULL, errp);
1271         break;
1272 
1273     default:
1274         error_setg(errp, "socket type unsupported for datagram");
1275         fd = -1;
1276     }
1277     return fd;
1278 }
1279 
1280 
1281 static SocketAddress *
1282 socket_sockaddr_to_address_inet(struct sockaddr_storage *sa,
1283                                 socklen_t salen,
1284                                 Error **errp)
1285 {
1286     char host[NI_MAXHOST];
1287     char serv[NI_MAXSERV];
1288     SocketAddress *addr;
1289     InetSocketAddress *inet;
1290     int ret;
1291 
1292     ret = getnameinfo((struct sockaddr *)sa, salen,
1293                       host, sizeof(host),
1294                       serv, sizeof(serv),
1295                       NI_NUMERICHOST | NI_NUMERICSERV);
1296     if (ret != 0) {
1297         error_setg(errp, "Cannot format numeric socket address: %s",
1298                    gai_strerror(ret));
1299         return NULL;
1300     }
1301 
1302     addr = g_new0(SocketAddress, 1);
1303     addr->type = SOCKET_ADDRESS_TYPE_INET;
1304     inet = &addr->u.inet;
1305     inet->host = g_strdup(host);
1306     inet->port = g_strdup(serv);
1307     if (sa->ss_family == AF_INET) {
1308         inet->has_ipv4 = inet->ipv4 = true;
1309     } else {
1310         inet->has_ipv6 = inet->ipv6 = true;
1311     }
1312 
1313     return addr;
1314 }
1315 
1316 
1317 static SocketAddress *
1318 socket_sockaddr_to_address_unix(struct sockaddr_storage *sa,
1319                                 socklen_t salen,
1320                                 Error **errp)
1321 {
1322     SocketAddress *addr;
1323     struct sockaddr_un *su = (struct sockaddr_un *)sa;
1324 
1325     addr = g_new0(SocketAddress, 1);
1326     addr->type = SOCKET_ADDRESS_TYPE_UNIX;
1327     salen -= offsetof(struct sockaddr_un, sun_path);
1328 #ifdef CONFIG_LINUX
1329     if (salen > 0 && !su->sun_path[0]) {
1330         /* Linux abstract socket */
1331         addr->u.q_unix.path = g_strndup(su->sun_path + 1, salen - 1);
1332         addr->u.q_unix.has_abstract = true;
1333         addr->u.q_unix.abstract = true;
1334         addr->u.q_unix.has_tight = true;
1335         addr->u.q_unix.tight = salen < sizeof(su->sun_path);
1336         return addr;
1337     }
1338 #endif
1339 
1340     addr->u.q_unix.path = g_strndup(su->sun_path, salen);
1341     return addr;
1342 }
1343 
1344 #ifdef CONFIG_AF_VSOCK
1345 static SocketAddress *
1346 socket_sockaddr_to_address_vsock(struct sockaddr_storage *sa,
1347                                  socklen_t salen,
1348                                  Error **errp)
1349 {
1350     SocketAddress *addr;
1351     VsockSocketAddress *vaddr;
1352     struct sockaddr_vm *svm = (struct sockaddr_vm *)sa;
1353 
1354     addr = g_new0(SocketAddress, 1);
1355     addr->type = SOCKET_ADDRESS_TYPE_VSOCK;
1356     vaddr = &addr->u.vsock;
1357     vaddr->cid = g_strdup_printf("%u", svm->svm_cid);
1358     vaddr->port = g_strdup_printf("%u", svm->svm_port);
1359 
1360     return addr;
1361 }
1362 #endif /* CONFIG_AF_VSOCK */
1363 
1364 SocketAddress *
1365 socket_sockaddr_to_address(struct sockaddr_storage *sa,
1366                            socklen_t salen,
1367                            Error **errp)
1368 {
1369     switch (sa->ss_family) {
1370     case AF_INET:
1371     case AF_INET6:
1372         return socket_sockaddr_to_address_inet(sa, salen, errp);
1373 
1374     case AF_UNIX:
1375         return socket_sockaddr_to_address_unix(sa, salen, errp);
1376 
1377 #ifdef CONFIG_AF_VSOCK
1378     case AF_VSOCK:
1379         return socket_sockaddr_to_address_vsock(sa, salen, errp);
1380 #endif
1381 
1382     default:
1383         error_setg(errp, "socket family %d unsupported",
1384                    sa->ss_family);
1385         return NULL;
1386     }
1387     return 0;
1388 }
1389 
1390 
1391 SocketAddress *socket_local_address(int fd, Error **errp)
1392 {
1393     struct sockaddr_storage ss;
1394     socklen_t sslen = sizeof(ss);
1395 
1396     if (getsockname(fd, (struct sockaddr *)&ss, &sslen) < 0) {
1397         error_setg_errno(errp, errno, "%s",
1398                          "Unable to query local socket address");
1399         return NULL;
1400     }
1401 
1402     return socket_sockaddr_to_address(&ss, sslen, errp);
1403 }
1404 
1405 
1406 SocketAddress *socket_remote_address(int fd, Error **errp)
1407 {
1408     struct sockaddr_storage ss;
1409     socklen_t sslen = sizeof(ss);
1410 
1411     if (getpeername(fd, (struct sockaddr *)&ss, &sslen) < 0) {
1412         error_setg_errno(errp, errno, "%s",
1413                          "Unable to query remote socket address");
1414         return NULL;
1415     }
1416 
1417     return socket_sockaddr_to_address(&ss, sslen, errp);
1418 }
1419 
1420 
1421 SocketAddress *socket_address_flatten(SocketAddressLegacy *addr_legacy)
1422 {
1423     SocketAddress *addr;
1424 
1425     if (!addr_legacy) {
1426         return NULL;
1427     }
1428 
1429     addr = g_new(SocketAddress, 1);
1430 
1431     switch (addr_legacy->type) {
1432     case SOCKET_ADDRESS_TYPE_INET:
1433         addr->type = SOCKET_ADDRESS_TYPE_INET;
1434         QAPI_CLONE_MEMBERS(InetSocketAddress, &addr->u.inet,
1435                            addr_legacy->u.inet.data);
1436         break;
1437     case SOCKET_ADDRESS_TYPE_UNIX:
1438         addr->type = SOCKET_ADDRESS_TYPE_UNIX;
1439         QAPI_CLONE_MEMBERS(UnixSocketAddress, &addr->u.q_unix,
1440                            addr_legacy->u.q_unix.data);
1441         break;
1442     case SOCKET_ADDRESS_TYPE_VSOCK:
1443         addr->type = SOCKET_ADDRESS_TYPE_VSOCK;
1444         QAPI_CLONE_MEMBERS(VsockSocketAddress, &addr->u.vsock,
1445                            addr_legacy->u.vsock.data);
1446         break;
1447     case SOCKET_ADDRESS_TYPE_FD:
1448         addr->type = SOCKET_ADDRESS_TYPE_FD;
1449         QAPI_CLONE_MEMBERS(String, &addr->u.fd, addr_legacy->u.fd.data);
1450         break;
1451     default:
1452         abort();
1453     }
1454 
1455     return addr;
1456 }
1457