call[fs]cgi: Ensure exit handlers are not called in failing children.
[ashd.git] / src / callscgi.c
CommitLineData
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1/*
2 ashd - A Sane HTTP Daemon
3 Copyright (C) 2008 Fredrik Tolf <fredrik@dolda2000.com>
4
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation, either version 3 of the License, or
8 (at your option) any later version.
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 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>.
17*/
18
19/*
20 * XXX: All the various ways to start a child process makes this
21 * program quite ugly at the moment. It is unclear whether it is
22 * meaningfully possible to unify them better than they currently are.
23 */
24
25#include <stdlib.h>
26#include <stdio.h>
27#include <unistd.h>
28#include <string.h>
29#include <fcntl.h>
30#include <ctype.h>
31#include <sys/socket.h>
32#include <sys/un.h>
33#include <netinet/in.h>
34#include <netdb.h>
35#include <sys/signal.h>
36#include <errno.h>
37
38#ifdef HAVE_CONFIG_H
39#include <config.h>
40#endif
41#include <utils.h>
42#include <req.h>
43#include <log.h>
44#include <mt.h>
45#include <mtio.h>
46
47static char **progspec;
48static char *sockid, *unspec, *inspec;
49static int nolisten;
50static struct sockaddr *curaddr;
51static size_t caddrlen;
52static int cafamily, isanon;
53static pid_t child;
54
55static struct addrinfo *resolv(int flags)
56{
57 int ret;
58 struct addrinfo *ai, h;
59 char *name, *srv, *p;
60
61 if((p = strchr(inspec, ':')) != NULL) {
62 name = smalloc(p - inspec + 1);
63 memcpy(name, inspec, p - inspec);
64 name[p - inspec] = 0;
65 srv = p + 1;
66 } else {
67 name = sstrdup("localhost");
68 srv = inspec;
69 }
70 memset(&h, 0, sizeof(h));
71 h.ai_family = AF_UNSPEC;
72 h.ai_socktype = SOCK_STREAM;
73 h.ai_flags = flags;
74 ret = getaddrinfo(name, srv, &h, &ai);
75 free(name);
76 if(ret != 0) {
77 flog(LOG_ERR, "could not resolve TCP specification `%s': %s", inspec, gai_strerror(ret));
78 exit(1);
79 }
80 return(ai);
81}
82
83static char *mksockid(char *sockid)
84{
85 char *home;
86
87 home = getenv("HOME");
88 if(home && !access(sprintf3("%s/.ashd/sockets/", home), X_OK))
89 return(sprintf3("%s/.ashd/sockets/scgi-p-%s", home, sockid));
90 return(sprintf3("/tmp/scgi-%i-%s", getuid(), sockid));
91}
92
93static char *mkanonid(void)
94{
95 char *home;
96 char *tmpl;
97 int fd;
98
99 home = getenv("HOME");
100 if(home && !access(sprintf3("%s/.ashd/sockets/", home), X_OK))
1376c0cd 101 tmpl = sprintf2("%s/.ashd/sockets/scgi-a-XXXXXX", home);
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102 else
103 tmpl = sprintf2("/tmp/scgi-a-%i-XXXXXX", getuid());
104 if((fd = mkstemp(tmpl)) < 0) {
105 flog(LOG_ERR, "could not create anonymous socket `%s': %s", tmpl, strerror(errno));
106 exit(1);
107 }
1376c0cd 108 close(fd);
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109 unlink(tmpl);
110 return(tmpl);
111}
112
113static void startlisten(void)
114{
115 int i, fd;
116 struct addrinfo *ai, *cai;
117 char *unpath;
118 struct sockaddr_un unm;
119 char *aname;
120
121 isanon = 0;
122 if(inspec != NULL) {
123 fd = -1;
124 for(cai = ai = resolv(AI_PASSIVE); cai != NULL; cai = cai->ai_next) {
125 if((fd = socket(cai->ai_family, cai->ai_socktype, cai->ai_protocol)) < 0)
126 continue;
127 if(bind(fd, cai->ai_addr, cai->ai_addrlen)) {
128 close(fd);
129 fd = -1;
130 continue;
131 }
132 if(listen(fd, 128)) {
133 close(fd);
134 fd = -1;
135 continue;
136 }
137 break;
138 }
139 freeaddrinfo(ai);
140 if(fd < 0) {
141 flog(LOG_ERR, "could not bind to specified TCP address: %s", strerror(errno));
142 exit(1);
143 }
144 } else if((unspec != NULL) || (sockid != NULL)) {
145 if((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
146 flog(LOG_ERR, "could not create Unix socket: %s", strerror(errno));
147 exit(1);
148 }
149 if(unspec != NULL)
150 unpath = unspec;
151 else
152 unpath = mksockid(sockid);
153 unlink(unpath);
154 unm.sun_family = AF_UNIX;
155 strcpy(unm.sun_path, unpath);
156 if(bind(fd, (struct sockaddr *)&unm, sizeof(unm))) {
157 flog(LOG_ERR, "could not bind Unix socket to `%s': %s", unspec, strerror(errno));
158 exit(1);
159 }
160 if(listen(fd, 128)) {
161 flog(LOG_ERR, "listen: %s", strerror(errno));
162 exit(1);
163 }
164 } else {
165 if((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
166 flog(LOG_ERR, "could not create Unix socket: %s", strerror(errno));
167 exit(1);
168 }
169 memset(&unm, 0, sizeof(unm));
170 aname = mkanonid();
171 unm.sun_family = AF_UNIX;
172 strcpy(unm.sun_path, aname);
173 free(aname);
174 if(bind(fd, (struct sockaddr *)&unm, sizeof(unm))) {
175 flog(LOG_ERR, "could not bind Unix socket to `%s': %s", unspec, strerror(errno));
176 exit(1);
177 }
178 if(listen(fd, 128)) {
179 flog(LOG_ERR, "listen: %s", strerror(errno));
180 exit(1);
181 }
182
183 curaddr = smalloc(caddrlen = sizeof(unm));
184 memcpy(curaddr, &unm, sizeof(unm));
185 cafamily = AF_UNIX;
186 isanon = 1;
187 }
188 if((child = fork()) < 0) {
189 flog(LOG_ERR, "could not fork: %s", strerror(errno));
190 exit(1);
191 }
192 if(child == 0) {
193 dup2(fd, 0);
194 for(i = 3; i < FD_SETSIZE; i++)
195 close(i);
196 execvp(*progspec, progspec);
7b9c1cff 197 flog(LOG_ERR, "callscgi: %s: %s", *progspec, strerror(errno));
107aa2ef 198 _exit(127);
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199 }
200 close(fd);
201}
202
203static void startnolisten(void)
204{
02cb2a3d 205 int i, fd;
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206
207 if((child = fork()) < 0) {
208 flog(LOG_ERR, "could not fork: %s", strerror(errno));
209 exit(1);
210 }
211 if(child == 0) {
212 for(i = 3; i < FD_SETSIZE; i++)
213 close(i);
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214 if((fd = open("/dev/null", O_RDONLY)) < 0) {
215 flog(LOG_ERR, "/dev/null: %s", strerror(errno));
107aa2ef 216 _exit(127);
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217 }
218 dup2(fd, 0);
219 close(fd);
f89ce57a 220 execvp(*progspec, progspec);
7b9c1cff 221 flog(LOG_ERR, "callscgi: %s: %s", *progspec, strerror(errno));
107aa2ef 222 _exit(127);
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223 }
224}
225
226static int sconnect(void)
227{
228 int fd;
229 int err;
230 socklen_t errlen;
231
232 fd = socket(cafamily, SOCK_STREAM, 0);
233 fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_NONBLOCK);
234 while(1) {
235 if(connect(fd, curaddr, caddrlen)) {
236 if(errno == EINPROGRESS) {
237 block(fd, EV_WRITE, 30);
238 errlen = sizeof(err);
239 if(getsockopt(fd, SOL_SOCKET, SO_ERROR, &err, &errlen) || ((errno = err) != 0)) {
240 close(fd);
241 return(-1);
242 }
243 return(fd);
244 }
245 close(fd);
246 return(-1);
247 }
248 return(fd);
249 }
250}
251
252static int econnect(void)
253{
254 int fd;
255 struct addrinfo *ai, *cai;
256 int tries;
257 char *unpath;
258 struct sockaddr_un unm;
259
260 tries = 0;
261retry:
262 if(inspec != NULL) {
263 fd = -1;
264 for(cai = ai = resolv(0); cai != NULL; cai = cai->ai_next) {
265 if((fd = socket(cai->ai_family, cai->ai_socktype, cai->ai_protocol)) < 0)
266 continue;
267 if(connect(fd, cai->ai_addr, cai->ai_addrlen)) {
268 close(fd);
269 fd = -1;
270 continue;
271 }
272 break;
273 }
f89ce57a 274 if(fd < 0) {
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275 if(tries++ < nolisten) {
276 sleep(1);
277 goto retry;
278 }
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279 flog(LOG_ERR, "could not connect to specified TCP address: %s", strerror(errno));
280 exit(1);
281 }
282 curaddr = smalloc(caddrlen = cai->ai_addrlen);
283 memcpy(curaddr, cai->ai_addr, caddrlen);
284 cafamily = cai->ai_family;
285 isanon = 0;
286 freeaddrinfo(ai);
287 return(fd);
288 } else if((unspec != NULL) || (sockid != NULL)) {
289 if((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
290 flog(LOG_ERR, "could not create Unix socket: %s", strerror(errno));
291 exit(1);
292 }
293 if(unspec != NULL)
294 unpath = unspec;
295 else
296 unpath = mksockid(sockid);
297 unlink(unpath);
298 unm.sun_family = AF_UNIX;
299 strcpy(unm.sun_path, unpath);
300 if(connect(fd, (struct sockaddr *)&unm, sizeof(unm))) {
301 close(fd);
302 if(tries++ < nolisten) {
303 sleep(1);
304 goto retry;
305 }
306 flog(LOG_ERR, "could not connect to Unix socket `%s': %s", unspec, strerror(errno));
307 exit(1);
308 }
309 curaddr = smalloc(caddrlen = sizeof(unm));
310 memcpy(curaddr, &unm, sizeof(unm));
311 cafamily = AF_UNIX;
312 isanon = 0;
313 return(fd);
314 } else {
425eccf6 315 flog(LOG_ERR, "callscgi: cannot use an anonymous socket without a program to start");
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316 exit(1);
317 }
318}
319
320static int startconn(void)
321{
322 if(*progspec) {
323 if(nolisten == 0)
324 startlisten();
325 else
326 startnolisten();
327 }
328 if(curaddr != NULL)
329 return(sconnect());
330 return(econnect());
331}
332
333static void killcuraddr(void)
334{
335 if(curaddr == NULL)
336 return;
337 if(isanon) {
338 unlink(((struct sockaddr_un *)curaddr)->sun_path);
339 if(child > 0)
340 kill(child, SIGTERM);
341 }
342 free(curaddr);
343 curaddr = NULL;
344}
345
346static int reconn(void)
347{
348 int fd;
349
350 if(curaddr != NULL) {
351 if((fd = sconnect()) >= 0)
352 return(fd);
353 killcuraddr();
354 }
355 return(startconn());
356}
357
358static off_t passdata(FILE *in, FILE *out)
359{
360 size_t read;
361 off_t total;
362 char buf[8192];
363
364 total = 0;
365 while(!feof(in)) {
366 read = fread(buf, 1, sizeof(buf), in);
367 if(ferror(in))
368 return(-1);
369 if(fwrite(buf, 1, read, out) != read)
370 return(-1);
371 total += read;
372 }
373 return(total);
374}
375
376static void bufaddenv(struct charbuf *dst, char *name, char *fmt, ...)
377{
378 va_list args;
379
380 bufcatstr2(*dst, name);
381 va_start(args, fmt);
382 bvprintf(dst, fmt, args);
383 va_end(args);
384 bufadd(*dst, 0);
385}
386
387static char *absolutify(char *file)
388{
389 static int inited = 0;
390 static char cwd[1024];
391
392 if(*file != '/') {
393 if(!inited) {
394 getcwd(cwd, sizeof(cwd));
395 inited = 1;
396 }
397 return(sprintf2("%s/%s", cwd, file));
398 }
399 return(sstrdup(file));
400}
401
402/* Mostly copied from callcgi. */
403static void mkcgienv(struct hthead *req, struct charbuf *dst)
404{
405 int i;
406 char *url, *qp, *h, *p;
407
408 bufaddenv(dst, "SERVER_SOFTWARE", "ashd/%s", VERSION);
409 bufaddenv(dst, "GATEWAY_INTERFACE", "CGI/1.1");
410 bufaddenv(dst, "SCGI", "1");
411 bufaddenv(dst, "SERVER_PROTOCOL", "%s", req->ver);
412 bufaddenv(dst, "REQUEST_METHOD", "%s", req->method);
413 bufaddenv(dst, "REQUEST_URI", "%s", req->url);
2d65add0 414 bufaddenv(dst, "PATH_INFO", req->rest);
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415 url = sstrdup(req->url);
416 if((qp = strchr(url, '?')) != NULL)
417 *(qp++) = 0;
418 /* XXX: This is an ugly hack (I think), but though I can think of
419 * several alternatives, none seem to be better. */
2d65add0
FT
420 if(*req->rest && (strlen(url) >= strlen(req->rest)) &&
421 !strcmp(req->rest, url + strlen(url) - strlen(req->rest))) {
422 bufaddenv(dst, "SCRIPT_NAME", "%.*s", (int)(strlen(url) - strlen(req->rest)), url);
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423 } else {
424 bufaddenv(dst, "SCRIPT_NAME", "%s", url);
425 }
426 bufaddenv(dst, "QUERY_STRING", "%s", qp?qp:"");
427 if((h = getheader(req, "Host")) != NULL)
428 bufaddenv(dst, "SERVER_NAME", "%s", h);
429 if((h = getheader(req, "X-Ash-Server-Port")) != NULL)
430 bufaddenv(dst, "SERVER_PORT", "%s", h);
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FT
431 if((h = getheader(req, "X-Ash-Remote-User")) != NULL)
432 bufaddenv(dst, "REMOTE_USER", "%s", h);
9230295c 433 if(((h = getheader(req, "X-Ash-Protocol")) != NULL) && !strcmp(h, "https"))
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434 bufaddenv(dst, "HTTPS", "on");
435 if((h = getheader(req, "X-Ash-Address")) != NULL)
436 bufaddenv(dst, "REMOTE_ADDR", "%s", h);
437 if((h = getheader(req, "Content-Type")) != NULL)
438 bufaddenv(dst, "CONTENT_TYPE", "%s", h);
439 if((h = getheader(req, "Content-Length")) != NULL)
440 bufaddenv(dst, "CONTENT_LENGTH", "%s", h);
441 else
442 bufaddenv(dst, "CONTENT_LENGTH", "0");
443 if((h = getheader(req, "X-Ash-File")) != NULL)
444 bufaddenv(dst, "SCRIPT_FILENAME", "%s", absolutify(h));
445 for(i = 0; i < req->noheaders; i++) {
02cb2a3d 446 h = sprintf2("HTTP_%s", req->headers[i][0]);
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447 for(p = h; *p; p++) {
448 if(isalnum(*p))
449 *p = toupper(*p);
450 else
451 *p = '_';
452 }
453 bufcatstr2(*dst, h);
454 free(h);
455 bufcatstr2(*dst, req->headers[i][1]);
456 }
457}
458
459static char *defstatus(int code)
460{
461 if(code == 200)
462 return("OK");
463 else if(code == 201)
464 return("Created");
465 else if(code == 202)
466 return("Accepted");
467 else if(code == 204)
468 return("No Content");
469 else if(code == 300)
470 return("Multiple Choices");
471 else if(code == 301)
472 return("Moved Permanently");
473 else if(code == 302)
474 return("Found");
475 else if(code == 303)
476 return("See Other");
477 else if(code == 304)
478 return("Not Modified");
479 else if(code == 307)
480 return("Moved Temporarily");
481 else if(code == 400)
482 return("Bad Request");
483 else if(code == 401)
484 return("Unauthorized");
485 else if(code == 403)
486 return("Forbidden");
487 else if(code == 404)
488 return("Not Found");
489 else if(code == 500)
490 return("Internal Server Error");
491 else if(code == 501)
492 return("Not Implemented");
493 else if(code == 503)
494 return("Service Unavailable");
495 else
496 return("Unknown status");
497}
498
499static struct hthead *parseresp(FILE *in)
500{
501 struct hthead *resp;
502 char *st, *p;
503
504 omalloc(resp);
505 resp->ver = sstrdup("HTTP/1.1");
506 if(parseheaders(resp, in)) {
507 freehthead(resp);
508 return(NULL);
509 }
510 if((st = getheader(resp, "Status")) != NULL) {
511 if((p = strchr(st, ' ')) != NULL) {
512 *(p++) = 0;
513 resp->code = atoi(st);
514 resp->msg = sstrdup(p);
515 } else {
516 resp->code = atoi(st);
517 resp->msg = sstrdup(defstatus(resp->code));
518 }
519 headrmheader(resp, "Status");
520 } else if(getheader(resp, "Location")) {
521 resp->code = 303;
522 resp->msg = sstrdup("See Other");
523 } else {
524 resp->code = 200;
525 resp->msg = sstrdup("OK");
526 }
527 return(resp);
528}
529
530static void serve(struct muth *muth, va_list args)
531{
532 vavar(struct hthead *, req);
533 vavar(int, fd);
534 vavar(int, sfd);
535 FILE *is, *os;
536 struct charbuf head;
537 struct hthead *resp;
538
539 sfd = reconn();
540 is = mtstdopen(fd, 1, 60, "r+");
541 os = mtstdopen(sfd, 1, 600, "r+");
542
543 bufinit(head);
544 mkcgienv(req, &head);
545 fprintf(os, "%zi:", head.d);
546 fwrite(head.b, head.d, 1, os);
547 fputc(',', os);
548 buffree(head);
549 if(passdata(is, os) < 0)
550 goto out;
551
552 if((resp = parseresp(os)) == NULL)
553 goto out;
554 writeresp(is, resp);
555 freehthead(resp);
556 fputc('\n', is);
557 if(passdata(os, is) < 0)
558 goto out;
559
560out:
561 freehthead(req);
562 fclose(is);
563 fclose(os);
564}
565
566static void listenloop(struct muth *muth, va_list args)
567{
568 vavar(int, lfd);
569 int fd;
570 struct hthead *req;
571
572 while(1) {
573 block(0, EV_READ, 0);
574 if((fd = recvreq(lfd, &req)) < 0) {
575 if(errno != 0)
576 flog(LOG_ERR, "recvreq: %s", strerror(errno));
577 break;
578 }
579 mustart(serve, req, fd);
580 }
581}
582
fd735432
FT
583static void sigign(int sig)
584{
585}
586
9c86e336
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587static void sigexit(int sig)
588{
589 exit(0);
590}
591
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592static void usage(FILE *out)
593{
425eccf6 594 fprintf(out, "usage: callscgi [-h] [-N RETRIES] [-i ID] [-u UNIX-PATH] [-t [HOST:]TCP-PORT] [PROGRAM [ARGS...]]\n");
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595}
596
597int main(int argc, char **argv)
598{
599 int c;
600
601 while((c = getopt(argc, argv, "+hN:i:u:t:")) >= 0) {
602 switch(c) {
603 case 'h':
604 usage(stdout);
605 exit(0);
606 case 'N':
607 nolisten = atoi(optarg);
608 break;
609 case 'i':
610 sockid = optarg;
611 break;
612 case 'u':
613 unspec = optarg;
614 break;
615 case 't':
616 inspec = optarg;
617 break;
618 default:
619 usage(stderr);
620 exit(1);
621 }
622 }
623 progspec = argv + optind;
624 if(((sockid != NULL) + (unspec != NULL) + (inspec != NULL)) > 1) {
425eccf6 625 flog(LOG_ERR, "callscgi: at most one of -i, -u or -t may be given");
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626 exit(1);
627 }
628 signal(SIGCHLD, SIG_IGN);
fd735432 629 signal(SIGPIPE, sigign);
9c86e336
FT
630 signal(SIGINT, sigexit);
631 signal(SIGTERM, sigexit);
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632 mustart(listenloop, 0);
633 atexit(killcuraddr);
634 ioloop();
635 return(0);
636}