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
26 # define X11_UNIX_PATH "/tmp/.X11-unix/X"
30 struct socket_function_table
*fn
;
31 /* the above variable absolutely *must* be the first in this structure */
39 int frozen
; /* this causes readability notifications to be ignored */
40 int frozen_readable
; /* this means we missed at least one readability
41 * notification while we were frozen */
42 int localhost_only
; /* for listening sockets */
45 int oobpending
; /* is there OOB data available to read? */
47 int pending_error
; /* in case send() returns error */
49 int nodelay
, keepalive
; /* for connect()-type sockets */
50 int privport
, port
; /* and again */
55 * We used to typedef struct Socket_tag *Socket.
57 * Since we have made the networking abstraction slightly more
58 * abstract, Socket no longer means a tcp socket (it could mean
59 * an ssl socket). So now we must use Actual_Socket when we know
60 * we are talking about a tcp socket.
62 typedef struct Socket_tag
*Actual_Socket
;
67 * Which address family this address belongs to. AF_INET for
68 * IPv4; AF_INET6 for IPv6; AF_UNSPEC indicates that name
69 * resolution has not been done and a simple host name is held
70 * in this SockAddr structure.
74 struct addrinfo
*ais
; /* Addresses IPv6 style. */
75 struct addrinfo
*ai
; /* steps along the linked list */
77 unsigned long *addresses
; /* Addresses IPv4 style. */
78 int naddresses
, curraddr
;
80 char hostname
[512]; /* Store an unresolved host name. */
83 static tree234
*sktree
;
85 static void uxsel_tell(Actual_Socket s
);
87 static int cmpfortree(void *av
, void *bv
)
89 Actual_Socket a
= (Actual_Socket
) av
, b
= (Actual_Socket
) bv
;
90 int as
= a
->s
, bs
= b
->s
;
98 static int cmpforsearch(void *av
, void *bv
)
100 Actual_Socket b
= (Actual_Socket
) bv
;
101 int as
= *(int *)av
, bs
= b
->s
;
111 sktree
= newtree234(cmpfortree
);
114 void sk_cleanup(void)
120 for (i
= 0; (s
= index234(sktree
, i
)) != NULL
; i
++) {
126 SockAddr
sk_namelookup(const char *host
, char **canonicalname
, int address_family
)
128 SockAddr ret
= snew(struct SockAddr_tag
);
130 struct addrinfo hints
;
134 struct hostent
*h
= NULL
;
139 /* Clear the structure and default to IPv4. */
140 memset(ret
, 0, sizeof(struct SockAddr_tag
));
141 ret
->family
= 0; /* We set this one when we have resolved the host. */
146 hints
.ai_flags
= AI_CANONNAME
;
147 hints
.ai_family
= (address_family
== ADDRTYPE_IPV4 ? AF_INET
:
148 address_family
== ADDRTYPE_IPV6 ? AF_INET6
:
150 hints
.ai_socktype
= SOCK_STREAM
;
151 hints
.ai_protocol
= 0;
152 hints
.ai_addrlen
= 0;
153 hints
.ai_addr
= NULL
;
154 hints
.ai_canonname
= NULL
;
155 hints
.ai_next
= NULL
;
156 err
= getaddrinfo(host
, NULL
, &hints
, &ret
->ais
);
159 ret
->error
= gai_strerror(err
);
162 ret
->family
= ret
->ai
->ai_family
;
164 if (ret
->ai
->ai_canonname
!= NULL
)
165 strncat(realhost
, ret
->ai
->ai_canonname
, sizeof(realhost
) - 1);
167 strncat(realhost
, host
, sizeof(realhost
) - 1);
169 if ((a
= inet_addr(host
)) == (unsigned long)(in_addr_t
)(-1)) {
171 * Otherwise use the IPv4-only gethostbyname... (NOTE:
172 * we don't use gethostbyname as a fallback!)
174 if (ret
->family
== 0) {
175 /*debug(("Resolving \"%s\" with gethostbyname() (IPv4 only)...\n", host)); */
176 if ( (h
= gethostbyname(host
)) )
177 ret
->family
= AF_INET
;
179 if (ret
->family
== 0) {
180 ret
->error
= (h_errno
== HOST_NOT_FOUND
||
181 h_errno
== NO_DATA
||
182 h_errno
== NO_ADDRESS ?
"Host does not exist" :
183 h_errno
== TRY_AGAIN ?
184 "Temporary name service failure" :
185 "gethostbyname: unknown error");
188 /* This way we are always sure the h->h_name is valid :) */
189 strncpy(realhost
, h
->h_name
, sizeof(realhost
));
190 for (n
= 0; h
->h_addr_list
[n
]; n
++);
191 ret
->addresses
= snewn(n
, unsigned long);
193 for (n
= 0; n
< ret
->naddresses
; n
++) {
194 memcpy(&a
, h
->h_addr_list
[n
], sizeof(a
));
195 ret
->addresses
[n
] = ntohl(a
);
199 * This must be a numeric IPv4 address because it caused a
200 * success return from inet_addr.
202 ret
->family
= AF_INET
;
203 strncpy(realhost
, host
, sizeof(realhost
));
204 ret
->addresses
= snew(unsigned long);
206 ret
->addresses
[0] = ntohl(a
);
210 realhost
[lenof(realhost
)-1] = '\0';
211 *canonicalname
= snewn(1+strlen(realhost
), char);
212 strcpy(*canonicalname
, realhost
);
216 SockAddr
sk_nonamelookup(const char *host
)
218 SockAddr ret
= snew(struct SockAddr_tag
);
220 ret
->family
= AF_UNSPEC
;
221 strncpy(ret
->hostname
, host
, lenof(ret
->hostname
));
222 ret
->hostname
[lenof(ret
->hostname
)-1] = '\0';
226 ret
->addresses
= NULL
;
231 static int sk_nextaddr(SockAddr addr
)
234 if (addr
->ai
->ai_next
) {
235 addr
->ai
= addr
->ai
->ai_next
;
236 addr
->family
= addr
->ai
->ai_family
;
241 if (addr
->curraddr
+1 < addr
->naddresses
) {
250 void sk_getaddr(SockAddr addr
, char *buf
, int buflen
)
253 if (addr
->family
== AF_UNSPEC
) {
254 strncpy(buf
, addr
->hostname
, buflen
);
255 buf
[buflen
-1] = '\0';
258 if (getnameinfo(addr
->ai
->ai_addr
, addr
->ai
->ai_addrlen
, buf
, buflen
,
259 NULL
, 0, NI_NUMERICHOST
) != 0) {
261 strncat(buf
, "<unknown>", buflen
- 1);
265 assert(addr
->family
== AF_INET
);
266 a
.s_addr
= htonl(addr
->addresses
[addr
->curraddr
]);
267 strncpy(buf
, inet_ntoa(a
), buflen
);
268 buf
[buflen
-1] = '\0';
273 int sk_hostname_is_local(char *name
)
275 return !strcmp(name
, "localhost");
278 #define ipv4_is_loopback(addr) \
279 (((addr).s_addr & htonl(0xff000000)) == htonl(0x7f000000))
281 static int sockaddr_is_loopback(struct sockaddr
*sa
)
283 struct sockaddr_in
*sin
;
285 struct sockaddr_in6
*sin6
;
288 switch (sa
->sa_family
) {
290 sin
= (struct sockaddr_in
*)sa
;
291 return ipv4_is_loopback(sin
->sin_addr
);
294 sin6
= (struct sockaddr_in6
*)sa
;
295 return IN6_IS_ADDR_LOOPBACK(&sin6
->sin6_addr
);
304 int sk_address_is_local(SockAddr addr
)
307 if (addr
->family
== AF_UNSPEC
)
308 return 0; /* we don't know; assume not */
311 return sockaddr_is_loopback(addr
->ai
->ai_addr
);
314 assert(addr
->family
== AF_INET
);
315 a
.s_addr
= htonl(addr
->addresses
[addr
->curraddr
]);
316 return ipv4_is_loopback(a
);
321 int sk_addrtype(SockAddr addr
)
323 return (addr
->family
== AF_INET ? ADDRTYPE_IPV4
:
325 addr
->family
== AF_INET6 ? ADDRTYPE_IPV6
:
330 void sk_addrcopy(SockAddr addr
, char *buf
)
334 if (addr
->family
== AF_INET
)
335 memcpy(buf
, &((struct sockaddr_in
*)addr
->ai
->ai_addr
)->sin_addr
,
336 sizeof(struct in_addr
));
337 else if (addr
->family
== AF_INET6
)
338 memcpy(buf
, &((struct sockaddr_in6
*)addr
->ai
->ai_addr
)->sin6_addr
,
339 sizeof(struct in6_addr
));
345 assert(addr
->family
== AF_INET
);
346 a
.s_addr
= htonl(addr
->addresses
[addr
->curraddr
]);
347 memcpy(buf
, (char*) &a
.s_addr
, 4);
351 void sk_addr_free(SockAddr addr
)
355 if (addr
->ais
!= NULL
)
356 freeaddrinfo(addr
->ais
);
358 sfree(addr
->addresses
);
363 static Plug
sk_tcp_plug(Socket sock
, Plug p
)
365 Actual_Socket s
= (Actual_Socket
) sock
;
372 static void sk_tcp_flush(Socket s
)
375 * We send data to the socket as soon as we can anyway,
376 * so we don't need to do anything here. :-)
380 static void sk_tcp_close(Socket s
);
381 static int sk_tcp_write(Socket s
, const char *data
, int len
);
382 static int sk_tcp_write_oob(Socket s
, const char *data
, int len
);
383 static void sk_tcp_set_private_ptr(Socket s
, void *ptr
);
384 static void *sk_tcp_get_private_ptr(Socket s
);
385 static void sk_tcp_set_frozen(Socket s
, int is_frozen
);
386 static const char *sk_tcp_socket_error(Socket s
);
388 static struct socket_function_table tcp_fn_table
= {
394 sk_tcp_set_private_ptr
,
395 sk_tcp_get_private_ptr
,
400 Socket
sk_register(OSSocket sockfd
, Plug plug
)
405 * Create Socket structure.
407 ret
= snew(struct Socket_tag
);
408 ret
->fn
= &tcp_fn_table
;
411 bufchain_init(&ret
->output_data
);
412 ret
->writable
= 1; /* to start with */
413 ret
->sending_oob
= 0;
415 ret
->frozen_readable
= 0;
416 ret
->localhost_only
= 0; /* unused, but best init anyway */
417 ret
->pending_error
= 0;
418 ret
->oobpending
= FALSE
;
425 ret
->error
= strerror(errno
);
437 static int try_connect(Actual_Socket sock
)
441 struct sockaddr_in6 a6
;
443 struct sockaddr_in a
;
444 struct sockaddr_un au
;
445 const struct sockaddr
*sa
;
453 plug_log(sock
->plug
, 0, sock
->addr
, sock
->port
, NULL
, 0);
458 assert(sock
->addr
->family
!= AF_UNSPEC
);
459 s
= socket(sock
->addr
->family
, SOCK_STREAM
, 0);
467 if (sock
->oobinline
) {
469 setsockopt(s
, SOL_SOCKET
, SO_OOBINLINE
, (void *) &b
, sizeof(b
));
474 setsockopt(s
, IPPROTO_TCP
, TCP_NODELAY
, (void *) &b
, sizeof(b
));
477 if (sock
->keepalive
) {
479 setsockopt(s
, SOL_SOCKET
, SO_KEEPALIVE
, (void *) &b
, sizeof(b
));
483 * Bind to local address.
486 localport
= 1023; /* count from 1023 downwards */
488 localport
= 0; /* just use port 0 (ie kernel picks) */
490 /* BSD IP stacks need sockaddr_in zeroed before filling in */
491 memset(&a
,'\0',sizeof(struct sockaddr_in
));
493 memset(&a6
,'\0',sizeof(struct sockaddr_in6
));
496 /* We don't try to bind to a local address for UNIX domain sockets. (Why
497 * do we bother doing the bind when localport == 0 anyway?) */
498 if(sock
->addr
->family
!= AF_UNIX
) {
499 /* Loop round trying to bind */
504 if (sock
->addr
->family
== AF_INET6
) {
505 /* XXX use getaddrinfo to get a local address? */
506 a6
.sin6_family
= AF_INET6
;
507 a6
.sin6_addr
= in6addr_any
;
508 a6
.sin6_port
= htons(localport
);
509 retcode
= bind(s
, (struct sockaddr
*) &a6
, sizeof(a6
));
513 assert(sock
->addr
->family
== AF_INET
);
514 a
.sin_family
= AF_INET
;
515 a
.sin_addr
.s_addr
= htonl(INADDR_ANY
);
516 a
.sin_port
= htons(localport
);
517 retcode
= bind(s
, (struct sockaddr
*) &a
, sizeof(a
));
524 if (err
!= EADDRINUSE
) /* failed, for a bad reason */
529 break; /* we're only looping once */
532 break; /* we might have got to the end */
540 * Connect to remote address.
542 switch(sock
->addr
->family
) {
545 /* XXX would be better to have got getaddrinfo() to fill in the port. */
546 ((struct sockaddr_in
*)sock
->addr
->ai
->ai_addr
)->sin_port
=
548 sa
= (const struct sockaddr
*)sock
->addr
->ai
->ai_addr
;
549 salen
= sock
->addr
->ai
->ai_addrlen
;
552 ((struct sockaddr_in
*)sock
->addr
->ai
->ai_addr
)->sin_port
=
554 sa
= (const struct sockaddr
*)sock
->addr
->ai
->ai_addr
;
555 salen
= sock
->addr
->ai
->ai_addrlen
;
559 a
.sin_family
= AF_INET
;
560 a
.sin_addr
.s_addr
= htonl(sock
->addr
->addresses
[sock
->addr
->curraddr
]);
561 a
.sin_port
= htons((short) sock
->port
);
562 sa
= (const struct sockaddr
*)&a
;
567 assert(sock
->port
== 0); /* to catch confused people */
568 assert(strlen(sock
->addr
->hostname
) < sizeof au
.sun_path
);
569 memset(&au
, 0, sizeof au
);
570 au
.sun_family
= AF_UNIX
;
571 strcpy(au
.sun_path
, sock
->addr
->hostname
);
572 sa
= (const struct sockaddr
*)&au
;
577 assert(0 && "unknown address family");
580 fl
= fcntl(s
, F_GETFL
);
582 fcntl(s
, F_SETFL
, fl
| O_NONBLOCK
);
584 if ((connect(s
, sa
, salen
)) < 0) {
585 if ( errno
!= EINPROGRESS
) {
591 * If we _don't_ get EWOULDBLOCK, the connect has completed
592 * and we should set the socket as connected and writable.
599 add234(sktree
, sock
);
603 plug_log(sock
->plug
, 1, sock
->addr
, sock
->port
, strerror(err
), err
);
607 Socket
sk_new(SockAddr addr
, int port
, int privport
, int oobinline
,
608 int nodelay
, int keepalive
, Plug plug
)
614 * Create Socket structure.
616 ret
= snew(struct Socket_tag
);
617 ret
->fn
= &tcp_fn_table
;
620 bufchain_init(&ret
->output_data
);
621 ret
->connected
= 0; /* to start with */
622 ret
->writable
= 0; /* to start with */
623 ret
->sending_oob
= 0;
625 ret
->frozen_readable
= 0;
626 ret
->localhost_only
= 0; /* unused, but best init anyway */
627 ret
->pending_error
= 0;
628 ret
->oobpending
= FALSE
;
632 ret
->oobinline
= oobinline
;
633 ret
->nodelay
= nodelay
;
634 ret
->keepalive
= keepalive
;
635 ret
->privport
= privport
;
640 err
= try_connect(ret
);
641 } while (err
&& sk_nextaddr(ret
->addr
));
644 ret
->error
= strerror(err
);
649 Socket
sk_newlistener(char *srcaddr
, int port
, Plug plug
, int local_host_only
, int address_family
)
653 struct addrinfo hints
, *ai
;
655 struct sockaddr_in6 a6
;
657 struct sockaddr
*addr
;
659 struct sockaddr_in a
;
665 * Create Socket structure.
667 ret
= snew(struct Socket_tag
);
668 ret
->fn
= &tcp_fn_table
;
671 bufchain_init(&ret
->output_data
);
672 ret
->writable
= 0; /* to start with */
673 ret
->sending_oob
= 0;
675 ret
->frozen_readable
= 0;
676 ret
->localhost_only
= local_host_only
;
677 ret
->pending_error
= 0;
678 ret
->oobpending
= FALSE
;
683 * Translate address_family from platform-independent constants
684 * into local reality.
686 address_family
= (address_family
== ADDRTYPE_IPV4 ? AF_INET
:
687 address_family
== ADDRTYPE_IPV6 ? AF_INET6
: AF_UNSPEC
);
690 /* Let's default to IPv6.
691 * If the stack doesn't support IPv6, we will fall back to IPv4. */
692 if (address_family
== AF_UNSPEC
) address_family
= AF_INET6
;
694 /* No other choice, default to IPv4 */
695 if (address_family
== AF_UNSPEC
) address_family
= AF_INET
;
701 s
= socket(address_family
, SOCK_STREAM
, 0);
703 /* If the host doesn't support IPv6 try fallback to IPv4. */
704 if (s
< 0 && address_family
== AF_INET6
) {
705 address_family
= AF_INET
;
706 s
= socket(address_family
, SOCK_STREAM
, 0);
710 ret
->error
= strerror(errno
);
716 setsockopt(s
, SOL_SOCKET
, SO_REUSEADDR
, (const char *)&on
, sizeof(on
));
719 addr
= NULL
; addrlen
= -1; /* placate optimiser */
721 if (srcaddr
!= NULL
) {
723 hints
.ai_flags
= AI_NUMERICHOST
;
724 hints
.ai_family
= address_family
;
725 hints
.ai_socktype
= SOCK_STREAM
;
726 hints
.ai_protocol
= 0;
727 hints
.ai_addrlen
= 0;
728 hints
.ai_addr
= NULL
;
729 hints
.ai_canonname
= NULL
;
730 hints
.ai_next
= NULL
;
731 assert(port
>= 0 && port
<= 99999);
732 sprintf(portstr
, "%d", port
);
733 retcode
= getaddrinfo(srcaddr
, portstr
, &hints
, &ai
);
736 addrlen
= ai
->ai_addrlen
;
739 memset(&a
,'\0',sizeof(struct sockaddr_in
));
740 a
.sin_family
= AF_INET
;
741 a
.sin_port
= htons(port
);
742 a
.sin_addr
.s_addr
= inet_addr(srcaddr
);
743 if (a
.sin_addr
.s_addr
!= (in_addr_t
)(-1)) {
744 /* Override localhost_only with specified listen addr. */
745 ret
->localhost_only
= ipv4_is_loopback(a
.sin_addr
);
748 addr
= (struct sockaddr
*)a
;
756 if (address_family
== AF_INET6
) {
757 memset(&a6
,'\0',sizeof(struct sockaddr_in6
));
758 a6
.sin6_family
= AF_INET6
;
759 a6
.sin6_port
= htons(port
);
761 a6
.sin6_addr
= in6addr_loopback
;
763 a6
.sin6_addr
= in6addr_any
;
764 addr
= (struct sockaddr
*)&a6
;
765 addrlen
= sizeof(a6
);
769 memset(&a
,'\0',sizeof(struct sockaddr_in
));
770 a
.sin_family
= AF_INET
;
771 a
.sin_port
= htons(port
);
773 a
.sin_addr
.s_addr
= htonl(INADDR_LOOPBACK
);
775 a
.sin_addr
.s_addr
= htonl(INADDR_ANY
);
776 addr
= (struct sockaddr
*)&a
;
781 retcode
= bind(s
, addr
, addrlen
);
784 ret
->error
= strerror(errno
);
788 if (listen(s
, SOMAXCONN
) < 0) {
790 ret
->error
= strerror(errno
);
802 static void sk_tcp_close(Socket sock
)
804 Actual_Socket s
= (Actual_Socket
) sock
;
810 sk_addr_free(s
->addr
);
814 int sk_getxdmdata(void *sock
, unsigned long *ip
, int *port
)
816 Actual_Socket s
= (Actual_Socket
) sock
;
817 struct sockaddr_in addr
;
821 * We must check that this socket really _is_ an Actual_Socket.
823 if (s
->fn
!= &tcp_fn_table
)
824 return 0; /* failure */
826 addrlen
= sizeof(addr
);
827 if (getsockname(s
->s
, (struct sockaddr
*)&addr
, &addrlen
) < 0)
829 switch(addr
.sin_family
) {
831 *ip
= ntohl(addr
.sin_addr
.s_addr
);
832 *port
= ntohs(addr
.sin_port
);
836 * For a Unix socket, we return 0xFFFFFFFF for the IP address and
837 * our current pid for the port. Bizarre, but such is life.
839 *ip
= ntohl(0xFFFFFFFF);
853 * The function which tries to send on a socket once it's deemed
856 void try_send(Actual_Socket s
)
858 while (s
->sending_oob
|| bufchain_size(&s
->output_data
) > 0) {
864 if (s
->sending_oob
) {
865 urgentflag
= MSG_OOB
;
866 len
= s
->sending_oob
;
870 bufchain_prefix(&s
->output_data
, &data
, &len
);
872 nsent
= send(s
->s
, data
, len
, urgentflag
);
873 noise_ultralight(nsent
);
875 err
= (nsent
< 0 ? errno
: 0);
876 if (err
== EWOULDBLOCK
) {
878 * Perfectly normal: we've sent all we can for the moment.
882 } else if (nsent
== 0 ||
883 err
== ECONNABORTED
|| err
== ECONNRESET
) {
885 * If send() returns CONNABORTED or CONNRESET, we
886 * unfortunately can't just call plug_closing(),
887 * because it's quite likely that we're currently
888 * _in_ a call from the code we'd be calling back
889 * to, so we'd have to make half the SSH code
890 * reentrant. Instead we flag a pending error on
891 * the socket, to be dealt with (by calling
892 * plug_closing()) at some suitable future moment.
894 s
->pending_error
= err
;
897 /* We're inside the Unix frontend here, so we know
898 * that the frontend handle is unnecessary. */
899 logevent(NULL
, strerror(err
));
900 fatalbox("%s", strerror(err
));
903 if (s
->sending_oob
) {
905 memmove(s
->oobdata
, s
->oobdata
+nsent
, len
-nsent
);
906 s
->sending_oob
= len
- nsent
;
911 bufchain_consume(&s
->output_data
, nsent
);
918 static int sk_tcp_write(Socket sock
, const char *buf
, int len
)
920 Actual_Socket s
= (Actual_Socket
) sock
;
923 * Add the data to the buffer list on the socket.
925 bufchain_add(&s
->output_data
, buf
, len
);
928 * Now try sending from the start of the buffer list.
934 * Update the select() status to correctly reflect whether or
935 * not we should be selecting for write.
939 return bufchain_size(&s
->output_data
);
942 static int sk_tcp_write_oob(Socket sock
, const char *buf
, int len
)
944 Actual_Socket s
= (Actual_Socket
) sock
;
947 * Replace the buffer list on the socket with the data.
949 bufchain_clear(&s
->output_data
);
950 assert(len
<= sizeof(s
->oobdata
));
951 memcpy(s
->oobdata
, buf
, len
);
952 s
->sending_oob
= len
;
955 * Now try sending from the start of the buffer list.
961 * Update the select() status to correctly reflect whether or
962 * not we should be selecting for write.
966 return s
->sending_oob
;
969 static int net_select_result(int fd
, int event
)
972 char buf
[20480]; /* nice big buffer for plenty of speed */
976 /* Find the Socket structure */
977 s
= find234(sktree
, &fd
, cmpforsearch
);
979 return 1; /* boggle */
981 noise_ultralight(event
);
984 case 4: /* exceptional */
987 * On a non-oobinline socket, this indicates that we
988 * can immediately perform an OOB read and get back OOB
989 * data, which we will send to the back end with
990 * type==2 (urgent data).
992 ret
= recv(s
->s
, buf
, sizeof(buf
), MSG_OOB
);
993 noise_ultralight(ret
);
995 const char *str
= (ret
== 0 ?
"Internal networking trouble" :
997 /* We're inside the Unix frontend here, so we know
998 * that the frontend handle is unnecessary. */
1000 fatalbox("%s", str
);
1003 * Receiving actual data on a socket means we can
1004 * stop falling back through the candidate
1005 * addresses to connect to.
1008 sk_addr_free(s
->addr
);
1011 return plug_receive(s
->plug
, 2, buf
, ret
);
1017 * If we reach here, this is an oobinline socket, which
1018 * means we should set s->oobpending and then deal with it
1019 * when we get called for the readability event (which
1020 * should also occur).
1022 s
->oobpending
= TRUE
;
1024 case 1: /* readable; also acceptance */
1027 * On a listening socket, the readability event means a
1028 * connection is ready to be accepted.
1031 struct sockaddr_in ss
;
1033 struct sockaddr_storage ss
;
1035 socklen_t addrlen
= sizeof(ss
);
1036 int t
; /* socket of connection */
1038 memset(&ss
, 0, addrlen
);
1039 t
= accept(s
->s
, (struct sockaddr
*)&ss
, &addrlen
);
1044 if (s
->localhost_only
&&
1045 !sockaddr_is_loopback((struct sockaddr
*)&ss
)) {
1046 close(t
); /* someone let nonlocal through?! */
1047 } else if (plug_accepting(s
->plug
, t
)) {
1048 close(t
); /* denied or error */
1054 * If we reach here, this is not a listening socket, so
1055 * readability really means readability.
1058 /* In the case the socket is still frozen, we don't even bother */
1060 s
->frozen_readable
= 1;
1065 * We have received data on the socket. For an oobinline
1066 * socket, this might be data _before_ an urgent pointer,
1067 * in which case we send it to the back end with type==1
1068 * (data prior to urgent).
1070 if (s
->oobinline
&& s
->oobpending
) {
1072 if (ioctl(s
->s
, SIOCATMARK
, &atmark
) == 0 && atmark
)
1073 s
->oobpending
= FALSE
; /* clear this indicator */
1077 ret
= recv(s
->s
, buf
, s
->oobpending ?
1 : sizeof(buf
), 0);
1078 noise_ultralight(ret
);
1080 if (errno
== EWOULDBLOCK
) {
1086 * An error at this point _might_ be an error reported
1087 * by a non-blocking connect(). So before we return a
1088 * panic status to the user, let's just see whether
1093 plug_log(s
->plug
, 1, s
->addr
, s
->port
, strerror(err
), err
);
1094 while (s
->addr
&& sk_nextaddr(s
->addr
)) {
1095 err
= try_connect(s
);
1099 return plug_closing(s
->plug
, strerror(err
), err
, 0);
1100 } else if (0 == ret
) {
1101 return plug_closing(s
->plug
, NULL
, 0, 0);
1104 * Receiving actual data on a socket means we can
1105 * stop falling back through the candidate
1106 * addresses to connect to.
1109 sk_addr_free(s
->addr
);
1112 return plug_receive(s
->plug
, atmark ?
0 : 1, buf
, ret
);
1115 case 2: /* writable */
1116 if (!s
->connected
) {
1118 * select() reports a socket as _writable_ when an
1119 * asynchronous connection is completed.
1121 s
->connected
= s
->writable
= 1;
1125 int bufsize_before
, bufsize_after
;
1127 bufsize_before
= s
->sending_oob
+ bufchain_size(&s
->output_data
);
1129 bufsize_after
= s
->sending_oob
+ bufchain_size(&s
->output_data
);
1130 if (bufsize_after
< bufsize_before
)
1131 plug_sent(s
->plug
, bufsize_after
);
1140 * Deal with socket errors detected in try_send().
1142 void net_pending_errors(void)
1148 * This might be a fiddly business, because it's just possible
1149 * that handling a pending error on one socket might cause
1150 * others to be closed. (I can't think of any reason this might
1151 * happen in current SSH implementation, but to maintain
1152 * generality of this network layer I'll assume the worst.)
1154 * So what we'll do is search the socket list for _one_ socket
1155 * with a pending error, and then handle it, and then search
1156 * the list again _from the beginning_. Repeat until we make a
1157 * pass with no socket errors present. That way we are
1158 * protected against the socket list changing under our feet.
1162 for (i
= 0; (s
= index234(sktree
, i
)) != NULL
; i
++) {
1163 if (s
->pending_error
) {
1165 * An error has occurred on this socket. Pass it to the
1168 plug_closing(s
->plug
, strerror(s
->pending_error
),
1169 s
->pending_error
, 0);
1177 * Each socket abstraction contains a `void *' private field in
1178 * which the client can keep state.
1180 static void sk_tcp_set_private_ptr(Socket sock
, void *ptr
)
1182 Actual_Socket s
= (Actual_Socket
) sock
;
1183 s
->private_ptr
= ptr
;
1186 static void *sk_tcp_get_private_ptr(Socket sock
)
1188 Actual_Socket s
= (Actual_Socket
) sock
;
1189 return s
->private_ptr
;
1193 * Special error values are returned from sk_namelookup and sk_new
1194 * if there's a problem. These functions extract an error message,
1195 * or return NULL if there's no problem.
1197 const char *sk_addr_error(SockAddr addr
)
1201 static const char *sk_tcp_socket_error(Socket sock
)
1203 Actual_Socket s
= (Actual_Socket
) sock
;
1207 static void sk_tcp_set_frozen(Socket sock
, int is_frozen
)
1209 Actual_Socket s
= (Actual_Socket
) sock
;
1210 if (s
->frozen
== is_frozen
)
1212 s
->frozen
= is_frozen
;
1213 if (!is_frozen
&& s
->frozen_readable
) {
1215 recv(s
->s
, &c
, 1, MSG_PEEK
);
1217 s
->frozen_readable
= 0;
1221 static void uxsel_tell(Actual_Socket s
)
1225 rwx
|= 2; /* write == connect */
1226 if (s
->connected
&& !s
->frozen
)
1227 rwx
|= 1 | 4; /* read, except */
1228 if (bufchain_size(&s
->output_data
))
1229 rwx
|= 2; /* write */
1231 rwx
|= 1; /* read == accept */
1232 uxsel_set(s
->s
, rwx
, net_select_result
);
1235 int net_service_lookup(char *service
)
1238 se
= getservbyname(service
, NULL
);
1240 return ntohs(se
->s_port
);
1245 SockAddr
platform_get_x11_unix_address(int displaynum
, char **canonicalname
)
1247 SockAddr ret
= snew(struct SockAddr_tag
);
1250 memset(ret
, 0, sizeof *ret
);
1251 ret
->family
= AF_UNIX
;
1252 n
= snprintf(ret
->hostname
, sizeof ret
->hostname
,
1253 "%s%d", X11_UNIX_PATH
, displaynum
);
1255 ret
->error
= "snprintf failed";
1256 else if(n
>= sizeof ret
->hostname
)
1257 ret
->error
= "X11 UNIX name too long";
1259 *canonicalname
= dupstr(ret
->hostname
);
1263 ret
->addresses
= NULL
;