1b7e21440dc3d627682f4d1a669217f4d4f82242
3 * $Id: socket.c,v 1.7 2001/06/22 19:37:00 mdw Exp $
5 * Socket source and target definitions
7 * (c) 1999 Straylight/Edgeware
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of the `fw' port forwarder.
14 * `fw' is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
19 * `fw' is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
24 * You should have received a copy of the GNU General Public License
25 * along with `fw'; if not, write to the Free Software Foundation,
26 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
29 /*----- Revision history --------------------------------------------------*
32 * Revision 1.7 2001/06/22 19:37:00 mdw
33 * New @conn_init@ interface.
35 * Revision 1.6 2001/02/03 20:30:03 mdw
36 * Support re-reading config files on SIGHUP.
38 * Revision 1.5 2000/03/23 23:20:42 mdw
39 * Remove listener even if connection option isn't SOCKOPT_LIMITED.
41 * Revision 1.4 1999/12/22 15:44:25 mdw
44 * Revision 1.3 1999/10/22 22:48:36 mdw
45 * New connection options: unlimited concurrent connections, and one-shot
48 * Revision 1.2 1999/07/27 18:30:53 mdw
49 * Various minor portability fixes.
51 * Revision 1.1 1999/07/26 23:33:32 mdw
52 * New sources and targets.
56 /*----- Header files ------------------------------------------------------*/
67 #include <sys/types.h>
70 #include <sys/socket.h>
71 #include <netinet/in.h>
72 #include <arpa/inet.h>
75 #include <mLib/alloc.h>
76 #include <mLib/conn.h>
77 #include <mLib/dstr.h>
78 #include <mLib/fdflags.h>
93 /*----- Data structures ---------------------------------------------------*/
95 /* --- Socket source options --- */
97 typedef struct ssource_opts
{
102 static ssource_opts ssgo
= { 256, 0 };
104 #define SOCKOPT_LIMIT 0u
105 #define SOCKOPT_NOLIMIT 1u
106 #define SOCKOPT_ONESHOT 2u
108 /* --- Socket source --- */
110 typedef struct ssource
{
119 /* --- Socket target --- */
121 typedef struct starget
{
127 /* --- Socket target endpoint --- */
129 typedef struct stept
{
135 /* --- Socket source endpoint --- */
137 typedef struct ssept
{
142 /*----- Protocol table ----------------------------------------------------*/
144 static addr_ops
*addrs
[] = { &inet_ops
, &un_ops
, 0 };
146 /*----- Other persistent variables ----------------------------------------*/
148 static addr_opts gao
= { 0 };
150 /*----- Parsing address types ---------------------------------------------*/
152 /* --- @getaddrtype@ --- *
154 * Arguments: @scanner *sc@ = pointer to scanner (for error reporting)
155 * @const char *p@ = pointer to protocol name
156 * @int abbrev@ = nonzero to allow abbreviations
158 * Returns: Pointer to address operations table or null.
160 * Use: Looks up a protocol name. Handy when parsing addresses and
161 * other bits of configuration. Returns null if no matching
165 static addr_ops
*getaddrtype(scanner
*sc
, const char *p
, int abbrev
)
168 addr_ops
*chosen
= 0;
169 size_t sz
= strlen(p
);
171 for (ops
= addrs
; *ops
; ops
++) {
172 if (strncmp((*ops
)->name
, p
, sz
) == 0) {
173 if ((*ops
)->name
[sz
] == 0)
175 else if (chosen
&& abbrev
)
176 error(sc
, "ambiguous socket address type `%s'", p
);
185 /* --- @getaddr@ --- *
187 * Arguments: @scanner *sc@ = pointer to scanner to read from
188 * @unsigned type@ = address type (@ADDR_SRC@ or @ADDR_DEST@)
190 * Returns: Pointer to an address successfully read.
192 * Use: Reads an optionally qualified address.
195 static addr
*getaddr(scanner
*sc
, unsigned type
)
204 if (sc
->t
== CTOK_WORD
)
205 ops
= getaddrtype(sc
, sc
->d
.buf
, abbrev
);
209 error(sc
, "unknown socket address type `%s'", sc
->d
.buf
);
215 return (ops
->read(sc
, type
));
218 /*----- Socket endpoints --------------------------------------------------*/
220 /* --- @wclose@ --- */
222 static void sept_wclose(endpt
*e
)
224 shutdown(e
->out
->fd
, 1);
227 /* --- @close@ (source) --- */
229 static void ss_listen(ssource */
*ss*/
);
231 static void ssept_close(endpt
*e
)
233 ssept
*ee
= (ssept
*)e
;
235 if (ee
->s
->o
.opt
== SOCKOPT_LIMIT
) {
237 if (ee
->s
->o
.conn
== 1)
241 REFFD_DEC(ee
->e
.out
);
246 /* --- @close@ (target) --- */
248 static void stept_close(endpt
*e
)
250 stept
*ee
= (stept
*)e
;
252 if (ee
->e
.f
& EPF_PENDING
)
256 REFFD_DEC(ee
->e
.out
);
264 /* --- @stept_go@ --- *
266 * Arguments: @int fd@ = file descriptor now ready for use
267 * @void *p@ = pointer to an endpoint structure
271 * Use: Handles successful connection of the target endpoint.
274 static void stept_go(int fd
, void *p
)
279 fw_log(-1, "[%s] connection failed: %s", e
->desc
, strerror(errno
));
282 reffd
*r
= reffd_init(fd
);
284 e
->e
.in
= e
->e
.out
= r
;
285 e
->e
.f
&= ~EPF_PENDING
;
287 endpt_join(&e
->e
, e
->e
.other
);
291 /* --- Socket endpoint definition --- */
293 static endpt_ops ssept_ops
= {
294 0, 0, sept_wclose
, ssept_close
297 static endpt_ops stept_ops
= {
298 0, 0, sept_wclose
, stept_close
301 /*----- Source definition -------------------------------------------------*/
303 /* --- @option@ --- */
305 static int ssource_option(source
*s
, scanner
*sc
)
307 ssource
*ss
= (ssource
*)s
;
308 ssource_opts
*sso
= ss ?
&ss
->o
: &ssgo
;
310 CONF_BEGIN(sc
, "socket", "socket")
312 /* --- Make sure the next token is a word --- */
314 if (sc
->t
!= CTOK_WORD
)
315 error(sc
, "parse error, option keyword expected");
317 /* --- Handle options at this level --- */
319 if (strcmp(sc
->d
.buf
, "conn") == 0) {
323 if (sc
->t
!= CTOK_WORD
)
324 error(sc
, "parse error, expected `unlimited', `one-shot' or number");
325 if (isdigit((unsigned char)sc
->d
.buf
[0])) {
326 sso
->conn
= atoi(sc
->d
.buf
);
328 error(sc
, "argument of `conn' must be positive");
329 sso
->opt
= SOCKOPT_LIMIT
;
333 sso
->opt
= 1 + (1 & conf_enum(sc
,
334 "unlimited,one-shot,infinite",
335 ENUM_ABBREV
, "`conn' option"));
340 if (strcmp(sc
->d
.buf
, "logging") == 0 ||
341 strcmp(sc
->d
.buf
, "log") == 0) {
342 addr_opts
*ao
= ss ? ss
->ao
: &gao
;
346 if (conf_enum(sc
, "no,yes", ENUM_ABBREV
, "logging status"))
347 ao
->f
&= ~ADDRF_NOLOG
;
349 ao
->f
|= ADDRF_NOLOG
;
353 /* --- Pass the option around the various address types --- */
356 if (ss
->a
->ops
->option
&& ss
->a
->ops
->option(sc
, ss ? ss
->ao
: 0))
360 for (a
= addrs
; *a
; a
++) {
361 if ((*a
)->option
&& (*a
)->option(sc
, 0))
366 /* --- Nobody understood the option --- */
373 static source
*ssource_read(scanner
*sc
)
377 (void)(conf_prefix(sc
, "socket") || conf_prefix(sc
, "sk"));
378 ss
= CREATE(ssource
);
379 ss
->s
.ops
= &ssource_ops
;
382 ss
->a
= getaddr(sc
, ADDR_SRC
);
383 if (ss
->a
->ops
->initopts
)
384 ss
->ao
= ss
->a
->ops
->initopts();
386 ss
->ao
= CREATE(addr_opts
);
392 /* --- @ss_accept@ --- *
394 * Arguments: @int fd@ = file descriptor to accept from
395 * @unsigned mode@ = what's ready with the descriptor
396 * @void *p@ = pointer to the source definition
400 * Use: Accepts an incoming connection and attaches it to a target
404 static void ssource_destroy(source */
*s*/
);
406 static void ss_accept(int fd
, unsigned mode
, void *p
)
413 /* --- Make the file descriptor --- */
417 if ((r
= ss
->a
->ops
->accept(fd
, ss
->ao
, ss
->s
.desc
)) == 0)
419 setsockopt(r
->fd
, SOL_SOCKET
, SO_OOBINLINE
, &opt
, sizeof(opt
));
420 fdflags(r
->fd
, O_NONBLOCK
, O_NONBLOCK
, FD_CLOEXEC
, FD_CLOEXEC
);
423 /* --- Make an endpoint --- */
426 e
->e
.ops
= &ssept_ops
;
430 e
->e
.in
= e
->e
.out
= r
;
434 /* --- Obtain the target endpoint and let rip --- */
436 if ((ee
= ss
->t
->ops
->create(ss
->t
, ss
->s
.desc
)) == 0) {
444 /* --- Remove the listening socket if necessary --- */
450 if (!(ss
->ao
->f
& ADDRF_NOLOG
))
451 fw_log(-1, "[%s] maximum connections reached", ss
->s
.desc
);
454 if (ss
->a
->ops
->unbind
)
455 ss
->a
->ops
->unbind(ss
->a
);
458 case SOCKOPT_NOLIMIT
:
460 case SOCKOPT_ONESHOT
:
463 if (ss
->a
->ops
->unbind
)
464 ss
->a
->ops
->unbind(ss
->a
);
465 ssource_destroy(&ss
->s
);
469 /* --- Let everything else happen --- */
471 endpt_join(&e
->e
, ee
);
474 /* --- @ss_listen@ --- *
476 * Arguments: @ssource *ss@ = source to listen on
480 * Use: Sets the socket to listen again, if it stopped for some
481 * reason. This is a copy of the code in the @read@ function,
482 * because it has different (wildly different) error handling
486 static void ss_listen(ssource
*ss
)
488 gen_addr
*ga
= (gen_addr
*)ss
->a
;
491 if (!(ss
->ao
->f
& ADDRF_NOLOG
))
492 fw_log(-1, "[%s] reattaching listener", ss
->s
.desc
);
494 /* --- Make the socket --- */
496 if ((fd
= socket(ga
->a
.ops
->pf
, SOCK_STREAM
, 0)) < 0) {
497 fw_log(-1, "[%s] couldn't create socket: %s",
498 ss
->s
.desc
, strerror(errno
));
502 /* --- Set it to allow address reuse --- */
506 setsockopt(fd
, SOL_SOCKET
, SO_REUSEADDR
, &opt
, sizeof(opt
));
507 fdflags(fd
, O_NONBLOCK
, O_NONBLOCK
, FD_CLOEXEC
, FD_CLOEXEC
);
510 /* --- Bind it to the right port --- */
512 if (bind(fd
, &ga
->sa
, ga
->a
.sz
)) {
513 fw_log(-1, "[%s] couldn't bind socket: %s", ss
->s
.desc
, strerror(errno
));
516 if (ga
->a
.ops
->bound
)
517 ga
->a
.ops
->bound(&ga
->a
, ss
->ao
);
519 /* --- Set it to listen for connections --- */
522 fw_log(-1, "[%s] couldn't listen on socket: %s",
523 ss
->s
.desc
, strerror(errno
));
527 /* --- Set the listener up again --- */
533 /* --- Tidy up if it failed --- *
535 * I'll just remove the entire source.
542 ssource_destroy(&ss
->s
);
545 /* --- @attach@ --- */
547 static void ssource_attach(source
*s
, scanner
*sc
, target
*t
)
549 ssource
*ss
= (ssource
*)s
;
554 /* --- Initialize the description string --- */
558 dstr_puts(&d
, "socket.");
559 ss
->a
->ops
->print(ss
->a
, ADDR_SRC
, &d
);
560 dstr_puts(&d
, " -> ");
561 dstr_puts(&d
, ss
->t
->desc
);
562 ss
->s
.desc
= xstrdup(d
.buf
);
566 /* --- Initialize the socket for listening --- */
569 gen_addr
*ga
= (gen_addr
*)ss
->a
;
571 /* --- Make the socket --- */
573 if ((fd
= socket(ga
->a
.ops
->pf
, SOCK_STREAM
, 0)) < 0)
574 error(sc
, "couldn't create socket: %s", strerror(errno
));
576 /* --- Set it to allow address reuse --- */
580 setsockopt(fd
, SOL_SOCKET
, SO_REUSEADDR
, &opt
, sizeof(opt
));
581 fdflags(fd
, O_NONBLOCK
, O_NONBLOCK
, FD_CLOEXEC
, FD_CLOEXEC
);
584 /* --- Bind it to the right port --- */
586 if (bind(fd
, &ga
->sa
, ga
->a
.sz
))
587 error(sc
, "couldn't bind to %s: %s", ss
->s
.desc
, strerror(errno
));
588 if (ga
->a
.ops
->bound
)
589 ga
->a
.ops
->bound(&ga
->a
, ss
->ao
);
591 /* --- Set it to listen for connections --- */
594 error(sc
, "couldn't listen on socket: %s", strerror(errno
));
597 /* --- We're ready to go now --- */
599 sel_initfile(sel
, &ss
->r
, fd
, SEL_READ
, ss_accept
, ss
);
605 /* --- @destroy@ --- */
607 static void ssource_destroy(source
*s
)
609 ssource
*ss
= (ssource
*)s
;
611 if (ss
->o
.conn
|| ss
->o
.opt
!= SOCKOPT_LIMIT
) {
614 if (ss
->a
->ops
->unbind
)
615 ss
->a
->ops
->unbind(ss
->a
);
617 if (ss
->a
->ops
->freeopts
)
618 ss
->a
->ops
->freeopts(ss
->ao
);
622 ss
->a
->ops
->destroy(ss
->a
);
623 ss
->t
->ops
->destroy(ss
->t
);
624 source_remove(&ss
->s
);
629 /* --- Source definition block --- */
631 source_ops ssource_ops
= {
633 ssource_option
, ssource_read
, ssource_attach
, ssource_destroy
636 /*----- Target definition -------------------------------------------------*/
640 static target
*starget_read(scanner
*sc
)
645 (void)(conf_prefix(sc
, "socket") || conf_prefix(sc
, "sk"));
646 st
= CREATE(starget
);
647 st
->t
.ops
= &starget_ops
;
648 st
->a
= getaddr(sc
, ADDR_DEST
);
649 dstr_puts(&d
, "socket.");
650 st
->a
->ops
->print(st
->a
, ADDR_DEST
, &d
);
651 st
->t
.desc
= xstrdup(d
.buf
);
656 /* --- @create@ --- *
658 * Arguments: @target *t@ = pointer to target
659 * @const char *desc@ = description of connection
661 * Returns: Pointer to a created endpoint.
663 * Use: Generates a target endpoint for communication.
666 static endpt
*starget_create(target
*t
, const char *desc
)
668 starget
*st
= (starget
*)t
;
669 stept
*e
= CREATE(stept
);
671 gen_addr
*ga
= (gen_addr
*)st
->a
;
674 if ((fd
= socket(st
->a
->ops
->pf
, SOCK_STREAM
, 0)) < 0)
676 setsockopt(fd
, SOL_SOCKET
, SO_OOBINLINE
, &opt
, sizeof(opt
));
677 fdflags(fd
, O_NONBLOCK
, O_NONBLOCK
, FD_CLOEXEC
, FD_CLOEXEC
);
678 e
->e
.ops
= &stept_ops
;
680 e
->e
.f
= EPF_FILE
| EPF_PENDING
;
682 e
->desc
= xstrdup(desc
);
684 if (conn_init(&e
->c
, sel
, fd
, &ga
->sa
, ga
->a
.sz
, stept_go
, e
)) {
685 fw_log(-1, "[%s] connection failed: %s", e
->desc
, strerror(errno
));
693 /* --- @destroy@ --- */
695 static void starget_destroy(target
*t
)
697 starget
*st
= (starget
*)t
;
698 st
->a
->ops
->destroy(st
->a
);
703 /* --- Socket target definition block --- */
705 target_ops starget_ops
= {
707 0, starget_read
, starget_create
, starget_destroy
710 /*----- That's all, folks -------------------------------------------------*/