2 * Unix networking abstraction.
11 #include <sys/types.h>
12 #include <sys/socket.h>
13 #include <sys/ioctl.h>
14 #include <arpa/inet.h>
15 #include <netinet/in.h>
16 #include <netinet/tcp.h>
20 #define DEFINE_PLUG_METHOD_MACROS
25 /* Solaris needs <sys/sockio.h> for SIOCATMARK. */
27 #include <sys/sockio.h>
31 # define X11_UNIX_PATH "/tmp/.X11-unix/X"
35 * We used to typedef struct Socket_tag *Socket.
37 * Since we have made the networking abstraction slightly more
38 * abstract, Socket no longer means a tcp socket (it could mean
39 * an ssl socket). So now we must use Actual_Socket when we know
40 * we are talking about a tcp socket.
42 typedef struct Socket_tag *Actual_Socket;
45 * Mutable state that goes with a SockAddr: stores information
46 * about where in the list of candidate IP(v*) addresses we've
49 typedef struct SockAddrStep_tag SockAddrStep;
50 struct SockAddrStep_tag {
52 struct addrinfo *ai; /* steps along addr->ais */
58 struct socket_function_table *fn;
59 /* the above variable absolutely *must* be the first in this structure */
65 int connected; /* irrelevant for listening sockets */
67 int frozen; /* this causes readability notifications to be ignored */
68 int frozen_readable; /* this means we missed at least one readability
69 * notification while we were frozen */
70 int localhost_only; /* for listening sockets */
73 int oobpending; /* is there OOB data available to read? */
75 int pending_error; /* in case send() returns error */
77 int nodelay, keepalive; /* for connect()-type sockets */
78 int privport, port; /* and again */
82 * We sometimes need pairs of Socket structures to be linked:
83 * if we are listening on the same IPv6 and v4 port, for
84 * example. So here we define `parent' and `child' pointers to
87 Actual_Socket parent, child;
93 enum { UNRESOLVED, UNIX, IP } superfamily;
95 struct addrinfo *ais; /* Addresses IPv6 style. */
97 unsigned long *addresses; /* Addresses IPv4 style. */
100 char hostname[512]; /* Store an unresolved host name. */
104 * Which address family this address belongs to. AF_INET for IPv4;
105 * AF_INET6 for IPv6; AF_UNSPEC indicates that name resolution has
106 * not been done and a simple host name is held in this SockAddr
110 #define SOCKADDR_FAMILY(addr, step) \
111 ((addr)->superfamily == UNRESOLVED ? AF_UNSPEC : \
112 (addr)->superfamily == UNIX ? AF_UNIX : \
113 (step).ai ? (step).ai->ai_family : AF_INET)
115 #define SOCKADDR_FAMILY(addr, step) \
116 ((addr)->superfamily == UNRESOLVED ? AF_UNSPEC : \
117 (addr)->superfamily == UNIX ? AF_UNIX : AF_INET)
121 * Start a SockAddrStep structure to step through multiple
125 #define START_STEP(addr, step) \
126 ((step).ai = (addr)->ais, (step).curraddr = 0)
128 #define START_STEP(addr, step) \
129 ((step).curraddr = 0)
132 static tree234 *sktree;
134 static void uxsel_tell(Actual_Socket s);
136 static int cmpfortree(void *av, void *bv)
138 Actual_Socket a = (Actual_Socket) av, b = (Actual_Socket) bv;
139 int as = a->s, bs = b->s;
151 static int cmpforsearch(void *av, void *bv)
153 Actual_Socket b = (Actual_Socket) bv;
154 int as = *(int *)av, bs = b->s;
164 sktree = newtree234(cmpfortree);
167 void sk_cleanup(void)
173 for (i = 0; (s = index234(sktree, i)) != NULL; i++) {
179 SockAddr sk_namelookup(const char *host, char **canonicalname, int address_family)
181 SockAddr ret = snew(struct SockAddr_tag);
183 struct addrinfo hints;
187 struct hostent *h = NULL;
192 /* Clear the structure and default to IPv4. */
193 memset(ret, 0, sizeof(struct SockAddr_tag));
194 ret->superfamily = UNRESOLVED;
200 hints.ai_flags = AI_CANONNAME;
201 hints.ai_family = (address_family == ADDRTYPE_IPV4 ? AF_INET :
202 address_family == ADDRTYPE_IPV6 ? AF_INET6 :
204 hints.ai_socktype = SOCK_STREAM;
205 hints.ai_protocol = 0;
206 hints.ai_addrlen = 0;
207 hints.ai_addr = NULL;
208 hints.ai_canonname = NULL;
209 hints.ai_next = NULL;
210 err = getaddrinfo(host, NULL, &hints, &ret->ais);
212 ret->error = gai_strerror(err);
215 ret->superfamily = IP;
217 if (ret->ais->ai_canonname != NULL)
218 strncat(realhost, ret->ais->ai_canonname, sizeof(realhost) - 1);
220 strncat(realhost, host, sizeof(realhost) - 1);
222 if ((a = inet_addr(host)) == (unsigned long)(in_addr_t)(-1)) {
224 * Otherwise use the IPv4-only gethostbyname... (NOTE:
225 * we don't use gethostbyname as a fallback!)
227 if (ret->superfamily == UNRESOLVED) {
228 /*debug(("Resolving \"%s\" with gethostbyname() (IPv4 only)...\n", host)); */
229 if ( (h = gethostbyname(host)) )
230 ret->superfamily = IP;
232 if (ret->superfamily == UNRESOLVED) {
233 ret->error = (h_errno == HOST_NOT_FOUND ||
234 h_errno == NO_DATA ||
235 h_errno == NO_ADDRESS ? "Host does not exist" :
236 h_errno == TRY_AGAIN ?
237 "Temporary name service failure" :
238 "gethostbyname: unknown error");
241 /* This way we are always sure the h->h_name is valid :) */
242 strncpy(realhost, h->h_name, sizeof(realhost));
243 for (n = 0; h->h_addr_list[n]; n++);
244 ret->addresses = snewn(n, unsigned long);
246 for (n = 0; n < ret->naddresses; n++) {
247 memcpy(&a, h->h_addr_list[n], sizeof(a));
248 ret->addresses[n] = ntohl(a);
252 * This must be a numeric IPv4 address because it caused a
253 * success return from inet_addr.
255 ret->superfamily = IP;
256 strncpy(realhost, host, sizeof(realhost));
257 ret->addresses = snew(unsigned long);
259 ret->addresses[0] = ntohl(a);
262 realhost[lenof(realhost)-1] = '\0';
263 *canonicalname = snewn(1+strlen(realhost), char);
264 strcpy(*canonicalname, realhost);
268 SockAddr sk_nonamelookup(const char *host)
270 SockAddr ret = snew(struct SockAddr_tag);
272 ret->superfamily = UNRESOLVED;
273 strncpy(ret->hostname, host, lenof(ret->hostname));
274 ret->hostname[lenof(ret->hostname)-1] = '\0';
278 ret->addresses = NULL;
284 static int sk_nextaddr(SockAddr addr, SockAddrStep *step)
287 if (step->ai && step->ai->ai_next) {
288 step->ai = step->ai->ai_next;
293 if (step->curraddr+1 < addr->naddresses) {
302 void sk_getaddr(SockAddr addr, char *buf, int buflen)
305 if (addr->superfamily == UNRESOLVED) {
306 strncpy(buf, addr->hostname, buflen);
307 buf[buflen-1] = '\0';
310 if (getnameinfo(addr->ais->ai_addr, addr->ais->ai_addrlen, buf, buflen,
311 NULL, 0, NI_NUMERICHOST) != 0) {
313 strncat(buf, "<unknown>", buflen - 1);
318 START_STEP(addr, step);
319 assert(SOCKADDR_FAMILY(addr, step) == AF_INET);
320 a.s_addr = htonl(addr->addresses[0]);
321 strncpy(buf, inet_ntoa(a), buflen);
322 buf[buflen-1] = '\0';
327 int sk_hostname_is_local(char *name)
329 return !strcmp(name, "localhost") ||
330 !strcmp(name, "::1") ||
331 !strncmp(name, "127.", 4);
334 #define ipv4_is_loopback(addr) \
335 (((addr).s_addr & htonl(0xff000000)) == htonl(0x7f000000))
337 static int sockaddr_is_loopback(struct sockaddr *sa)
339 struct sockaddr_in *sin;
341 struct sockaddr_in6 *sin6;
344 switch (sa->sa_family) {
346 sin = (struct sockaddr_in *)sa;
347 return ipv4_is_loopback(sin->sin_addr);
350 sin6 = (struct sockaddr_in6 *)sa;
351 return IN6_IS_ADDR_LOOPBACK(&sin6->sin6_addr);
360 int sk_address_is_local(SockAddr addr)
363 if (addr->superfamily == UNRESOLVED)
364 return 0; /* we don't know; assume not */
367 return sockaddr_is_loopback(addr->ais->ai_addr);
371 START_STEP(addr, step);
372 assert(SOCKADDR_FAMILY(addr, step) == AF_INET);
373 a.s_addr = htonl(addr->addresses[0]);
374 return ipv4_is_loopback(a);
379 int sk_addrtype(SockAddr addr)
383 START_STEP(addr, step);
384 family = SOCKADDR_FAMILY(addr, step);
386 return (family == AF_INET ? ADDRTYPE_IPV4 :
388 family == AF_INET6 ? ADDRTYPE_IPV6 :
393 void sk_addrcopy(SockAddr addr, char *buf)
397 START_STEP(addr, step);
398 family = SOCKADDR_FAMILY(addr, step);
401 if (family == AF_INET)
402 memcpy(buf, &((struct sockaddr_in *)step.ai->ai_addr)->sin_addr,
403 sizeof(struct in_addr));
404 else if (family == AF_INET6)
405 memcpy(buf, &((struct sockaddr_in6 *)step.ai->ai_addr)->sin6_addr,
406 sizeof(struct in6_addr));
412 assert(family == AF_INET);
413 a.s_addr = htonl(addr->addresses[step.curraddr]);
414 memcpy(buf, (char*) &a.s_addr, 4);
418 void sk_addr_free(SockAddr addr)
420 if (--addr->refcount > 0)
423 if (addr->ais != NULL)
424 freeaddrinfo(addr->ais);
426 sfree(addr->addresses);
431 SockAddr sk_addr_dup(SockAddr addr)
437 static Plug sk_tcp_plug(Socket sock, Plug p)
439 Actual_Socket s = (Actual_Socket) sock;
446 static void sk_tcp_flush(Socket s)
449 * We send data to the socket as soon as we can anyway,
450 * so we don't need to do anything here. :-)
454 static void sk_tcp_close(Socket s);
455 static int sk_tcp_write(Socket s, const char *data, int len);
456 static int sk_tcp_write_oob(Socket s, const char *data, int len);
457 static void sk_tcp_set_private_ptr(Socket s, void *ptr);
458 static void *sk_tcp_get_private_ptr(Socket s);
459 static void sk_tcp_set_frozen(Socket s, int is_frozen);
460 static const char *sk_tcp_socket_error(Socket s);
462 static struct socket_function_table tcp_fn_table = {
468 sk_tcp_set_private_ptr,
469 sk_tcp_get_private_ptr,
474 Socket sk_register(OSSocket sockfd, Plug plug)
479 * Create Socket structure.
481 ret = snew(struct Socket_tag);
482 ret->fn = &tcp_fn_table;
485 bufchain_init(&ret->output_data);
486 ret->writable = 1; /* to start with */
487 ret->sending_oob = 0;
489 ret->frozen_readable = 0;
490 ret->localhost_only = 0; /* unused, but best init anyway */
491 ret->pending_error = 0;
492 ret->oobpending = FALSE;
494 ret->parent = ret->child = NULL;
501 ret->error = strerror(errno);
513 static int try_connect(Actual_Socket sock)
517 struct sockaddr_in6 a6;
519 struct sockaddr_in a;
520 struct sockaddr_un au;
521 const struct sockaddr *sa;
524 int fl, salen, family;
527 * Remove the socket from the tree before we overwrite its
528 * internal socket id, because that forms part of the tree's
529 * sorting criterion. We'll add it back before exiting this
530 * function, whether we changed anything or not.
532 del234(sktree, sock);
537 plug_log(sock->plug, 0, sock->addr, sock->port, NULL, 0);
542 family = SOCKADDR_FAMILY(sock->addr, sock->step);
543 assert(family != AF_UNSPEC);
544 s = socket(family, SOCK_STREAM, 0);
554 if (sock->oobinline) {
556 setsockopt(s, SOL_SOCKET, SO_OOBINLINE, (void *) &b, sizeof(b));
561 setsockopt(s, IPPROTO_TCP, TCP_NODELAY, (void *) &b, sizeof(b));
564 if (sock->keepalive) {
566 setsockopt(s, SOL_SOCKET, SO_KEEPALIVE, (void *) &b, sizeof(b));
570 * Bind to local address.
573 localport = 1023; /* count from 1023 downwards */
575 localport = 0; /* just use port 0 (ie kernel picks) */
577 /* BSD IP stacks need sockaddr_in zeroed before filling in */
578 memset(&a,'\0',sizeof(struct sockaddr_in));
580 memset(&a6,'\0',sizeof(struct sockaddr_in6));
583 /* We don't try to bind to a local address for UNIX domain sockets. (Why
584 * do we bother doing the bind when localport == 0 anyway?) */
585 if (family != AF_UNIX) {
586 /* Loop round trying to bind */
591 if (family == AF_INET6) {
592 /* XXX use getaddrinfo to get a local address? */
593 a6.sin6_family = AF_INET6;
594 a6.sin6_addr = in6addr_any;
595 a6.sin6_port = htons(localport);
596 retcode = bind(s, (struct sockaddr *) &a6, sizeof(a6));
600 assert(family == AF_INET);
601 a.sin_family = AF_INET;
602 a.sin_addr.s_addr = htonl(INADDR_ANY);
603 a.sin_port = htons(localport);
604 retcode = bind(s, (struct sockaddr *) &a, sizeof(a));
611 if (err != EADDRINUSE) /* failed, for a bad reason */
616 break; /* we're only looping once */
619 break; /* we might have got to the end */
627 * Connect to remote address.
632 /* XXX would be better to have got getaddrinfo() to fill in the port. */
633 ((struct sockaddr_in *)sock->step.ai->ai_addr)->sin_port =
635 sa = (const struct sockaddr *)sock->step.ai->ai_addr;
636 salen = sock->step.ai->ai_addrlen;
639 ((struct sockaddr_in *)sock->step.ai->ai_addr)->sin_port =
641 sa = (const struct sockaddr *)sock->step.ai->ai_addr;
642 salen = sock->step.ai->ai_addrlen;
646 a.sin_family = AF_INET;
647 a.sin_addr.s_addr = htonl(sock->addr->addresses[sock->step.curraddr]);
648 a.sin_port = htons((short) sock->port);
649 sa = (const struct sockaddr *)&a;
654 assert(sock->port == 0); /* to catch confused people */
655 assert(strlen(sock->addr->hostname) < sizeof au.sun_path);
656 memset(&au, 0, sizeof au);
657 au.sun_family = AF_UNIX;
658 strcpy(au.sun_path, sock->addr->hostname);
659 sa = (const struct sockaddr *)&au;
664 assert(0 && "unknown address family");
665 exit(1); /* XXX: GCC doesn't understand assert() on some systems. */
668 fl = fcntl(s, F_GETFL);
670 fcntl(s, F_SETFL, fl | O_NONBLOCK);
672 if ((connect(s, sa, salen)) < 0) {
673 if ( errno != EINPROGRESS ) {
679 * If we _don't_ get EWOULDBLOCK, the connect has completed
680 * and we should set the socket as connected and writable.
691 * No matter what happened, put the socket back in the tree.
693 add234(sktree, sock);
696 plug_log(sock->plug, 1, sock->addr, sock->port, strerror(err), err);
700 Socket sk_new(SockAddr addr, int port, int privport, int oobinline,
701 int nodelay, int keepalive, Plug plug)
707 * Create Socket structure.
709 ret = snew(struct Socket_tag);
710 ret->fn = &tcp_fn_table;
713 bufchain_init(&ret->output_data);
714 ret->connected = 0; /* to start with */
715 ret->writable = 0; /* to start with */
716 ret->sending_oob = 0;
718 ret->frozen_readable = 0;
719 ret->localhost_only = 0; /* unused, but best init anyway */
720 ret->pending_error = 0;
721 ret->parent = ret->child = NULL;
722 ret->oobpending = FALSE;
725 START_STEP(ret->addr, ret->step);
727 ret->oobinline = oobinline;
728 ret->nodelay = nodelay;
729 ret->keepalive = keepalive;
730 ret->privport = privport;
735 err = try_connect(ret);
736 } while (err && sk_nextaddr(ret->addr, &ret->step));
739 ret->error = strerror(err);
744 Socket sk_newlistener(char *srcaddr, int port, Plug plug, int local_host_only, int orig_address_family)
748 struct addrinfo hints, *ai;
750 struct sockaddr_in6 a6;
752 struct sockaddr *addr;
754 struct sockaddr_in a;
761 * Create Socket structure.
763 ret = snew(struct Socket_tag);
764 ret->fn = &tcp_fn_table;
767 bufchain_init(&ret->output_data);
768 ret->writable = 0; /* to start with */
769 ret->sending_oob = 0;
771 ret->frozen_readable = 0;
772 ret->localhost_only = local_host_only;
773 ret->pending_error = 0;
774 ret->parent = ret->child = NULL;
775 ret->oobpending = FALSE;
780 * Translate address_family from platform-independent constants
781 * into local reality.
783 address_family = (orig_address_family == ADDRTYPE_IPV4 ? AF_INET :
785 orig_address_family == ADDRTYPE_IPV6 ? AF_INET6 :
790 /* Let's default to IPv6.
791 * If the stack doesn't support IPv6, we will fall back to IPv4. */
792 if (address_family == AF_UNSPEC) address_family = AF_INET6;
794 /* No other choice, default to IPv4 */
795 if (address_family == AF_UNSPEC) address_family = AF_INET;
801 s = socket(address_family, SOCK_STREAM, 0);
804 /* If the host doesn't support IPv6 try fallback to IPv4. */
805 if (s < 0 && address_family == AF_INET6) {
806 address_family = AF_INET;
807 s = socket(address_family, SOCK_STREAM, 0);
812 ret->error = strerror(errno);
820 setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (const char *)&on, sizeof(on));
823 addr = NULL; addrlen = -1; /* placate optimiser */
825 if (srcaddr != NULL) {
827 hints.ai_flags = AI_NUMERICHOST;
828 hints.ai_family = address_family;
829 hints.ai_socktype = SOCK_STREAM;
830 hints.ai_protocol = 0;
831 hints.ai_addrlen = 0;
832 hints.ai_addr = NULL;
833 hints.ai_canonname = NULL;
834 hints.ai_next = NULL;
835 assert(port >= 0 && port <= 99999);
836 sprintf(portstr, "%d", port);
837 retcode = getaddrinfo(srcaddr, portstr, &hints, &ai);
840 addrlen = ai->ai_addrlen;
843 memset(&a,'\0',sizeof(struct sockaddr_in));
844 a.sin_family = AF_INET;
845 a.sin_port = htons(port);
846 a.sin_addr.s_addr = inet_addr(srcaddr);
847 if (a.sin_addr.s_addr != (in_addr_t)(-1)) {
848 /* Override localhost_only with specified listen addr. */
849 ret->localhost_only = ipv4_is_loopback(a.sin_addr);
851 addr = (struct sockaddr *)&a;
859 if (address_family == AF_INET6) {
860 memset(&a6,'\0',sizeof(struct sockaddr_in6));
861 a6.sin6_family = AF_INET6;
862 a6.sin6_port = htons(port);
864 a6.sin6_addr = in6addr_loopback;
866 a6.sin6_addr = in6addr_any;
867 addr = (struct sockaddr *)&a6;
868 addrlen = sizeof(a6);
872 memset(&a,'\0',sizeof(struct sockaddr_in));
873 a.sin_family = AF_INET;
874 a.sin_port = htons(port);
876 a.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
878 a.sin_addr.s_addr = htonl(INADDR_ANY);
879 addr = (struct sockaddr *)&a;
884 retcode = bind(s, addr, addrlen);
887 ret->error = strerror(errno);
891 if (listen(s, SOMAXCONN) < 0) {
893 ret->error = strerror(errno);
899 * If we were given ADDRTYPE_UNSPEC, we must also create an
900 * IPv4 listening socket and link it to this one.
902 if (address_family == AF_INET6 && orig_address_family == ADDRTYPE_UNSPEC) {
905 other = (Actual_Socket) sk_newlistener(srcaddr, port, plug,
906 local_host_only, ADDRTYPE_IPV4);
913 /* If we couldn't create a listening socket on IPv4 as well
914 * as IPv6, we must return an error overall. */
917 return (Socket) other;
931 static void sk_tcp_close(Socket sock)
933 Actual_Socket s = (Actual_Socket) sock;
936 sk_tcp_close((Socket)s->child);
942 sk_addr_free(s->addr);
946 void *sk_getxdmdata(void *sock, int *lenp)
948 Actual_Socket s = (Actual_Socket) sock;
950 struct sockaddr_in addr;
952 struct sockaddr_storage addr;
953 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&addr;
955 struct sockaddr *sa = (struct sockaddr *)&addr;
956 struct sockaddr_in *sin = (struct sockaddr_in *)&addr;
959 static unsigned int unix_addr = 0xFFFFFFFF;
962 * We must check that this socket really _is_ an Actual_Socket.
964 if (s->fn != &tcp_fn_table)
965 return NULL; /* failure */
967 addrlen = sizeof(addr);
968 if (getsockname(s->s, sa, &addrlen) < 0)
970 switch(sa->sa_family) {
973 buf = snewn(*lenp, char);
974 PUT_32BIT_MSB_FIRST(buf, ntohl(sin->sin_addr.s_addr));
975 PUT_16BIT_MSB_FIRST(buf+4, ntohs(sin->sin_port));
980 buf = snewn(*lenp, char);
981 if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
982 memcpy(buf, sin6->sin6_addr.s6_addr + 12, 4);
983 PUT_16BIT_MSB_FIRST(buf+4, ntohs(sin6->sin6_port));
985 /* This is stupid, but it's what XLib does. */
991 buf = snewn(*lenp, char);
992 PUT_32BIT_MSB_FIRST(buf, unix_addr--);
993 PUT_16BIT_MSB_FIRST(buf+4, getpid());
1006 * The function which tries to send on a socket once it's deemed
1009 void try_send(Actual_Socket s)
1011 while (s->sending_oob || bufchain_size(&s->output_data) > 0) {
1015 int len, urgentflag;
1017 if (s->sending_oob) {
1018 urgentflag = MSG_OOB;
1019 len = s->sending_oob;
1023 bufchain_prefix(&s->output_data, &data, &len);
1025 nsent = send(s->s, data, len, urgentflag);
1026 noise_ultralight(nsent);
1028 err = (nsent < 0 ? errno : 0);
1029 if (err == EWOULDBLOCK) {
1031 * Perfectly normal: we've sent all we can for the moment.
1033 s->writable = FALSE;
1037 * We unfortunately can't just call plug_closing(),
1038 * because it's quite likely that we're currently
1039 * _in_ a call from the code we'd be calling back
1040 * to, so we'd have to make half the SSH code
1041 * reentrant. Instead we flag a pending error on
1042 * the socket, to be dealt with (by calling
1043 * plug_closing()) at some suitable future moment.
1045 s->pending_error = err;
1049 if (s->sending_oob) {
1051 memmove(s->oobdata, s->oobdata+nsent, len-nsent);
1052 s->sending_oob = len - nsent;
1057 bufchain_consume(&s->output_data, nsent);
1064 static int sk_tcp_write(Socket sock, const char *buf, int len)
1066 Actual_Socket s = (Actual_Socket) sock;
1069 * Add the data to the buffer list on the socket.
1071 bufchain_add(&s->output_data, buf, len);
1074 * Now try sending from the start of the buffer list.
1080 * Update the select() status to correctly reflect whether or
1081 * not we should be selecting for write.
1085 return bufchain_size(&s->output_data);
1088 static int sk_tcp_write_oob(Socket sock, const char *buf, int len)
1090 Actual_Socket s = (Actual_Socket) sock;
1093 * Replace the buffer list on the socket with the data.
1095 bufchain_clear(&s->output_data);
1096 assert(len <= sizeof(s->oobdata));
1097 memcpy(s->oobdata, buf, len);
1098 s->sending_oob = len;
1101 * Now try sending from the start of the buffer list.
1107 * Update the select() status to correctly reflect whether or
1108 * not we should be selecting for write.
1112 return s->sending_oob;
1115 static int net_select_result(int fd, int event)
1118 char buf[20480]; /* nice big buffer for plenty of speed */
1122 /* Find the Socket structure */
1123 s = find234(sktree, &fd, cmpforsearch);
1125 return 1; /* boggle */
1127 noise_ultralight(event);
1130 case 4: /* exceptional */
1131 if (!s->oobinline) {
1133 * On a non-oobinline socket, this indicates that we
1134 * can immediately perform an OOB read and get back OOB
1135 * data, which we will send to the back end with
1136 * type==2 (urgent data).
1138 ret = recv(s->s, buf, sizeof(buf), MSG_OOB);
1139 noise_ultralight(ret);
1141 return plug_closing(s->plug,
1142 ret == 0 ? "Internal networking trouble" :
1143 strerror(errno), errno, 0);
1146 * Receiving actual data on a socket means we can
1147 * stop falling back through the candidate
1148 * addresses to connect to.
1151 sk_addr_free(s->addr);
1154 return plug_receive(s->plug, 2, buf, ret);
1160 * If we reach here, this is an oobinline socket, which
1161 * means we should set s->oobpending and then deal with it
1162 * when we get called for the readability event (which
1163 * should also occur).
1165 s->oobpending = TRUE;
1167 case 1: /* readable; also acceptance */
1170 * On a listening socket, the readability event means a
1171 * connection is ready to be accepted.
1174 struct sockaddr_in ss;
1176 struct sockaddr_storage ss;
1178 socklen_t addrlen = sizeof(ss);
1179 int t; /* socket of connection */
1182 memset(&ss, 0, addrlen);
1183 t = accept(s->s, (struct sockaddr *)&ss, &addrlen);
1188 fl = fcntl(t, F_GETFL);
1190 fcntl(t, F_SETFL, fl | O_NONBLOCK);
1192 if (s->localhost_only &&
1193 !sockaddr_is_loopback((struct sockaddr *)&ss)) {
1194 close(t); /* someone let nonlocal through?! */
1195 } else if (plug_accepting(s->plug, t)) {
1196 close(t); /* denied or error */
1202 * If we reach here, this is not a listening socket, so
1203 * readability really means readability.
1206 /* In the case the socket is still frozen, we don't even bother */
1208 s->frozen_readable = 1;
1213 * We have received data on the socket. For an oobinline
1214 * socket, this might be data _before_ an urgent pointer,
1215 * in which case we send it to the back end with type==1
1216 * (data prior to urgent).
1218 if (s->oobinline && s->oobpending) {
1220 if (ioctl(s->s, SIOCATMARK, &atmark) == 0 && atmark)
1221 s->oobpending = FALSE; /* clear this indicator */
1225 ret = recv(s->s, buf, s->oobpending ? 1 : sizeof(buf), 0);
1226 noise_ultralight(ret);
1228 if (errno == EWOULDBLOCK) {
1234 * An error at this point _might_ be an error reported
1235 * by a non-blocking connect(). So before we return a
1236 * panic status to the user, let's just see whether
1241 plug_log(s->plug, 1, s->addr, s->port, strerror(err), err);
1242 while (s->addr && sk_nextaddr(s->addr, &s->step)) {
1243 err = try_connect(s);
1247 return plug_closing(s->plug, strerror(err), err, 0);
1248 } else if (0 == ret) {
1249 return plug_closing(s->plug, NULL, 0, 0);
1252 * Receiving actual data on a socket means we can
1253 * stop falling back through the candidate
1254 * addresses to connect to.
1257 sk_addr_free(s->addr);
1260 return plug_receive(s->plug, atmark ? 0 : 1, buf, ret);
1263 case 2: /* writable */
1264 if (!s->connected) {
1266 * select() reports a socket as _writable_ when an
1267 * asynchronous connection is completed.
1269 s->connected = s->writable = 1;
1273 int bufsize_before, bufsize_after;
1275 bufsize_before = s->sending_oob + bufchain_size(&s->output_data);
1277 bufsize_after = s->sending_oob + bufchain_size(&s->output_data);
1278 if (bufsize_after < bufsize_before)
1279 plug_sent(s->plug, bufsize_after);
1288 * Deal with socket errors detected in try_send().
1290 void net_pending_errors(void)
1296 * This might be a fiddly business, because it's just possible
1297 * that handling a pending error on one socket might cause
1298 * others to be closed. (I can't think of any reason this might
1299 * happen in current SSH implementation, but to maintain
1300 * generality of this network layer I'll assume the worst.)
1302 * So what we'll do is search the socket list for _one_ socket
1303 * with a pending error, and then handle it, and then search
1304 * the list again _from the beginning_. Repeat until we make a
1305 * pass with no socket errors present. That way we are
1306 * protected against the socket list changing under our feet.
1310 for (i = 0; (s = index234(sktree, i)) != NULL; i++) {
1311 if (s->pending_error) {
1313 * An error has occurred on this socket. Pass it to the
1316 plug_closing(s->plug, strerror(s->pending_error),
1317 s->pending_error, 0);
1325 * Each socket abstraction contains a `void *' private field in
1326 * which the client can keep state.
1328 static void sk_tcp_set_private_ptr(Socket sock, void *ptr)
1330 Actual_Socket s = (Actual_Socket) sock;
1331 s->private_ptr = ptr;
1334 static void *sk_tcp_get_private_ptr(Socket sock)
1336 Actual_Socket s = (Actual_Socket) sock;
1337 return s->private_ptr;
1341 * Special error values are returned from sk_namelookup and sk_new
1342 * if there's a problem. These functions extract an error message,
1343 * or return NULL if there's no problem.
1345 const char *sk_addr_error(SockAddr addr)
1349 static const char *sk_tcp_socket_error(Socket sock)
1351 Actual_Socket s = (Actual_Socket) sock;
1355 static void sk_tcp_set_frozen(Socket sock, int is_frozen)
1357 Actual_Socket s = (Actual_Socket) sock;
1358 if (s->frozen == is_frozen)
1360 s->frozen = is_frozen;
1361 if (!is_frozen && s->frozen_readable) {
1363 recv(s->s, &c, 1, MSG_PEEK);
1365 s->frozen_readable = 0;
1369 static void uxsel_tell(Actual_Socket s)
1373 rwx |= 1; /* read == accept */
1376 rwx |= 2; /* write == connect */
1377 if (s->connected && !s->frozen)
1378 rwx |= 1 | 4; /* read, except */
1379 if (bufchain_size(&s->output_data))
1380 rwx |= 2; /* write */
1382 uxsel_set(s->s, rwx, net_select_result);
1385 int net_service_lookup(char *service)
1388 se = getservbyname(service, NULL);
1390 return ntohs(se->s_port);
1395 SockAddr platform_get_x11_unix_address(const char *sockpath, int displaynum)
1397 SockAddr ret = snew(struct SockAddr_tag);
1400 memset(ret, 0, sizeof *ret);
1401 ret->superfamily = UNIX;
1403 * In special circumstances (notably Mac OS X Leopard), we'll
1404 * have been passed an explicit Unix socket path.
1407 n = snprintf(ret->hostname, sizeof ret->hostname,
1410 n = snprintf(ret->hostname, sizeof ret->hostname,
1411 "%s%d", X11_UNIX_PATH, displaynum);
1415 ret->error = "snprintf failed";
1416 else if (n >= sizeof ret->hostname)
1417 ret->error = "X11 UNIX name too long";
1422 ret->addresses = NULL;
1423 ret->naddresses = 0;