1 %{
2 
3 /*
4  * Copyright (c) 2021, 2022, 2023 Omar Polo <op@omarpolo.com>
5  * Copyright (c) 2018 Florian Obser <florian@openbsd.org>
6  * Copyright (c) 2004, 2005 Esben Norby <norby@openbsd.org>
7  * Copyright (c) 2004 Ryan McBride <mcbride@openbsd.org>
8  * Copyright (c) 2002, 2003, 2004 Henning Brauer <henning@openbsd.org>
9  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
10  * Copyright (c) 2001 Daniel Hartmeier.  All rights reserved.
11  * Copyright (c) 2001 Theo de Raadt.  All rights reserved.
12  *
13  * Permission to use, copy, modify, and distribute this software for any
14  * purpose with or without fee is hereby granted, provided that the above
15  * copyright notice and this permission notice appear in all copies.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
18  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
20  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
21  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
22  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
23  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
24  */
25 
26 #include "gmid.h"
27 
28 #include <ctype.h>
29 #include <errno.h>
30 #include <netdb.h>
31 #include <stdarg.h>
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <string.h>
35 
36 #include "log.h"
37 
38 struct conf *conf;
39 
40 static const char	*default_host = "*";
41 static uint16_t		 default_port = 1965;
42 
43 TAILQ_HEAD(files, file)		 files = TAILQ_HEAD_INITIALIZER(files);
44 static struct file {
45 	TAILQ_ENTRY(file)	 entry;
46 	FILE			*stream;
47 	char			*name;
48 	size_t	 		 ungetpos;
49 	size_t			 ungetsize;
50 	u_char			*ungetbuf;
51 	int			 eof_reached;
52 	int			 lineno;
53 	int			 errors;
54 } *file, *topfile;
55 
56 struct file	*pushfile(const char *, int);
57 int		 popfile(void);
58 int		 yyparse(void);
59 int		 yylex(void);
60 void		 yyerror(const char *, ...)
61     __attribute__((__format__ (printf, 1, 2)))
62     __attribute__((__nonnull__ (1)));
63 void		 yywarn(const char *, ...)
64     __attribute__((__format__ (printf, 1, 2)))
65     __attribute__((__nonnull__ (1)));
66 int		 kw_cmp(const void *, const void *);
67 int		 lookup(char *);
68 int		 igetc(void);
69 int		 lgetc(int);
70 void		 lungetc(int);
71 int		 findeol(void);
72 
73 /*
74  * #define YYDEBUG 1
75  * int yydebug = 1;
76  */
77 
78 TAILQ_HEAD(symhead, sym) symhead = TAILQ_HEAD_INITIALIZER(symhead);
79 struct sym {
80 	TAILQ_ENTRY(sym)	 entry;
81 	int			 used;
82 	int			 persist;
83 	char			*name;
84 	char			*val;
85 };
86 
87 int	 symset(const char *, const char *, int);
88 char	*symget(const char *);
89 
90 char		*ensure_absolute_path(char*);
91 int		 check_block_code(int);
92 char		*check_block_fmt(char*);
93 int		 check_strip_no(int);
94 int		 check_port_num(int);
95 int		 check_prefork_num(int);
96 void		 advance_loc(void);
97 void		 advance_proxy(void);
98 void		 parsehp(char *, char **, const char **, const char *);
99 int		 fastcgi_conf(const char *, const char *);
100 void		 add_param(char *, char *);
101 int		 getservice(const char *);
102 void		 listen_on(const char *, const char *);
103 
104 static struct vhost		*host;
105 static struct location		*loc;
106 static struct proxy		*proxy;
107 static char			*current_media;
108 static int			 errors;
109 
110 typedef struct {
111 	union {
112 		char	*string;
113 		int	 number;
114 	} v;
115 	int lineno;
116 } YYSTYPE;
117 
118 #define YYSTYPE YYSTYPE
119 
120 %}
121 
122 /* for bison: */
123 /* %define parse.error verbose */
124 
125 %token	ALIAS AUTO
126 %token	BLOCK
127 %token	CA CERT CHROOT CLIENT
128 %token	DEFAULT
129 %token	FASTCGI FOR_HOST
130 %token	INCLUDE INDEX IPV6
131 %token	KEY
132 %token	LANG LISTEN LOCATION LOG
133 %token	OCSP OFF ON
134 %token	PARAM PORT PREFORK PROTO PROTOCOLS PROXY
135 %token	RELAY_TO REQUIRE RETURN ROOT
136 %token	SERVER SNI SOCKET STRIP
137 %token	TCP TOEXT TYPE TYPES
138 %token	USE_TLS USER
139 %token	VERIFYNAME
140 
141 %token	ERROR
142 
143 %token	<v.string>	STRING
144 %token	<v.number>	NUM
145 
146 %type	<v.number>	bool proxy_port
147 %type	<v.string>	string numberstring listen_addr
148 
149 %%
150 
151 conf		: /* empty */
152 		| conf include '\n'
153 		| conf '\n'
154 		| conf varset '\n'
155 		| conf option '\n'
156 		| conf vhost '\n'
157 		| conf types '\n'
158 		| conf error '\n'		{ file->errors++; }
159 		;
160 
161 include		: INCLUDE STRING		{
162 			struct file	*nfile;
163 
164 			if ((nfile = pushfile($2, 0)) == NULL) {
165 				yyerror("failed to include file %s", $2);
166 				free($2);
167 				YYERROR;
168 			}
169 			free($2);
170 
171 			file = nfile;
172 			lungetc('\n');
173 		}
174 		;
175 
176 bool		: ON	{ $$ = 1; }
177 		| OFF	{ $$ = 0; }
178 		;
179 
180 string		: string STRING	{
181 			if (asprintf(&$$, "%s%s", $1, $2) == -1) {
182 				free($1);
183 				free($2);
184 				yyerror("string: asprintf: %s", strerror(errno));
185 				YYERROR;
186 			}
187 			free($1);
188 			free($2);
189 		}
190 		| STRING
191 		;
192 
193 numberstring	: NUM {
194 			char *s;
195 			if (asprintf(&s, "%d", $1) == -1) {
196 				yyerror("asprintf: number");
197 				YYERROR;
198 			}
199 			$$ = s;
200 		}
201 		| STRING
202 		;
203 
204 varset		: STRING '=' string		{
205 			char *s = $1;
206 			while (*s++) {
207 				if (isspace((unsigned char)*s)) {
208 					yyerror("macro name cannot contain "
209 					    "whitespaces");
210 					free($1);
211 					free($3);
212 					YYERROR;
213 				}
214 			}
215 			symset($1, $3, 0);
216 			free($1);
217 			free($3);
218 		}
219 		;
220 
221 option		: CHROOT string	{
222 			if (strlcpy(conf->chroot, $2, sizeof(conf->chroot)) >=
223 			    sizeof(conf->chroot))
224 				yyerror("chroot path too long");
225 			free($2);
226 		}
227 		| IPV6 bool {
228 			yywarn("option `ipv6' is deprecated,"
229 			    " please use `listen on'");
230 			if ($2)
231 				default_host = "*";
232 			else
233 				default_host = "0.0.0.0";
234 		}
235 		| PORT NUM {
236 			yywarn("option `port' is deprecated,"
237 			    " please use `listen on'");
238 			default_port = $2;
239 		}
240 		| PREFORK NUM		{ conf->prefork = check_prefork_num($2); }
241 		| PROTOCOLS string {
242 			if (tls_config_parse_protocols(&conf->protos, $2) == -1)
243 				yyerror("invalid protocols string \"%s\"", $2);
244 			free($2);
245 		}
246 		| USER string {
247 			if (strlcpy(conf->user, $2, sizeof(conf->user)) >=
248 			    sizeof(conf->user))
249 				yyerror("user name too long");
250 			free($2);
251 		}
252 		;
253 
254 vhost		: SERVER string {
255 			host = new_vhost();
256 			TAILQ_INSERT_HEAD(&conf->hosts, host, vhosts);
257 
258 			loc = new_location();
259 			TAILQ_INSERT_HEAD(&host->locations, loc, locations);
260 
261 			TAILQ_INIT(&host->proxies);
262 
263 			(void) strlcpy(loc->match, "*", sizeof(loc->match));
264 			(void) strlcpy(host->domain, $2, sizeof(host->domain));
265 
266 			if (strstr($2, "xn--") != NULL) {
267 				yywarn("\"%s\" looks like punycode: you "
268 				    "should use the decoded hostname", $2);
269 			}
270 
271 			free($2);
272 		} '{' optnl servbody '}' {
273 			if (host->cert_path == NULL ||
274 			    host->key_path == NULL)
275 				yyerror("invalid vhost definition: %s",
276 				    host->domain);
277 			if (TAILQ_EMPTY(&host->addrs)) {
278 				char portno[32];
279 				int r;
280 
281 				r = snprintf(portno, sizeof(portno), "%d",
282 				    default_port);
283 				if (r < 0 || (size_t)r >= sizeof(portno))
284 					fatal("snprintf");
285 
286 				yywarn("missing `listen on' in server %s,"
287 				    " assuming %s port %d", $2, default_host,
288 				    default_port);
289 				listen_on(default_host, portno);
290 			}
291 		}
292 		| error '}'		{ yyerror("bad server directive"); }
293 		;
294 
295 servbody	: /* empty */
296 		| servbody servopt optnl
297 		| servbody location optnl
298 		| servbody proxy optnl
299 		;
300 
301 listen_addr	: '*' { $$ = NULL; }
302 		| STRING
303 		;
304 
305 servopt		: ALIAS string {
306 			struct alist *a;
307 
308 			a = xcalloc(1, sizeof(*a));
309 			(void) strlcpy(a->alias, $2, sizeof(a->alias));
310 			free($2);
311 			TAILQ_INSERT_TAIL(&host->aliases, a, aliases);
312 		}
313 		| CERT string		{
314 			ensure_absolute_path($2);
315 			free(host->cert_path);
316 			host->cert_path = $2;
317 		}
318 		| KEY string		{
319 			ensure_absolute_path($2);
320 			free(host->key_path);
321 			host->key_path = $2;
322 		}
323 		| OCSP string		{
324 			ensure_absolute_path($2);
325 			free(host->ocsp_path);
326 			host->ocsp_path = $2;
327 		}
328 		| PARAM string '=' string {
329 			yywarn("the top-level `param' directive is deprecated."
330 			    "  Please use `fastcgi { param ... }`");
331 			add_param($2, $4);
332 		}
333 		| LISTEN ON listen_addr {
334 			listen_on($3, "1965");
335 		}
336 		| LISTEN ON listen_addr PORT STRING {
337 			listen_on($3, $5);
338 			free($3);
339 			free($5);
340 		}
341 		| LISTEN ON listen_addr PORT NUM {
342 			char portno[32];
343 			int r;
344 
345 			r = snprintf(portno, sizeof(portno), "%d", $5);
346 			if (r < 0 || (size_t)r >= sizeof(portno))
347 				fatal("snprintf");
348 
349 			listen_on($3, portno);
350 			free($3);
351 		}
352 		| locopt
353 		;
354 
355 proxy		: PROXY { advance_proxy(); }
356 		  proxy_matches '{' optnl proxy_opts '}' {
357 			if (*proxy->host == '\0')
358 				yyerror("invalid proxy block: missing `relay-to' option");
359 
360 			if ((proxy->cert_path == NULL && proxy->key_path != NULL) ||
361 			    (proxy->cert_path != NULL && proxy->key_path == NULL))
362 				yyerror("invalid proxy block: missing cert or key");
363 		}
364 		;
365 
366 proxy_matches	: /* empty */
367 		| proxy_matches proxy_match
368 		;
369 
370 proxy_port	: /* empty */	{ $$ = 1965; }
371 		| PORT STRING {
372 			if (($$ = getservice($2)) == -1)
373 				yyerror("invalid port number %s", $2);
374 			free($2);
375 		}
376 		| PORT NUM	{ $$ = $2; }
377 		;
378 
379 proxy_match	: PROTO string {
380 			(void) strlcpy(proxy->match_proto, $2, sizeof(proxy->match_proto));
381 			free($2);
382 		}
383 		| FOR_HOST string proxy_port {
384 			(void) strlcpy(proxy->match_host, $2, sizeof(proxy->match_host));
385 			(void) snprintf(proxy->match_port, sizeof(proxy->match_port),
386 			    "%d", $3);
387 			free($2);
388 		}
389 		;
390 
391 proxy_opts	: /* empty */
392 		| proxy_opts proxy_opt optnl
393 		;
394 
395 proxy_opt	: CERT string {
396 			free(proxy->cert);
397 			ensure_absolute_path($2);
398 			proxy->cert_path = $2;
399 		}
400 		| KEY string {
401 			free(proxy->key);
402 			ensure_absolute_path($2);
403 			proxy->key_path = $2;
404 		}
405 		| PROTOCOLS string {
406 			if (tls_config_parse_protocols(&proxy->protocols, $2) == -1)
407 				yyerror("invalid protocols string \"%s\"", $2);
408 			free($2);
409 		}
410 		| RELAY_TO string proxy_port {
411 			(void) strlcpy(proxy->host, $2, sizeof(proxy->host));
412 			(void) snprintf(proxy->port, sizeof(proxy->port),
413 			    "%d", $3);
414 			free($2);
415 		}
416 		| REQUIRE CLIENT CA string {
417 			ensure_absolute_path($4);
418 			proxy->reqca_path = $4;
419 		}
420 		| SNI string {
421 			(void) strlcpy(proxy->sni, $2, sizeof(proxy->sni));
422 			free($2);
423 		}
424 		| USE_TLS bool {
425 			proxy->notls = !$2;
426 		}
427 		| VERIFYNAME bool {
428 			proxy->noverifyname = !$2;
429 		}
430 		;
431 
432 location	: LOCATION { advance_loc(); } string '{' optnl locopts '}' {
433 			/* drop the starting '/' if any */
434 			if (*$3 == '/')
435 				memmove($3, $3+1, strlen($3));
436 			(void) strlcpy(loc->match, $3, sizeof(loc->match));
437 			free($3);
438 		}
439 		| error '}'
440 		;
441 
442 locopts		: /* empty */
443 		| locopts locopt optnl
444 		;
445 
446 locopt		: AUTO INDEX bool	{ loc->auto_index = $3 ? 1 : -1; }
447 		| BLOCK RETURN NUM string {
448 			check_block_fmt($4);
449 			(void) strlcpy(loc->block_fmt, $4, sizeof(loc->block_fmt));
450 			loc->block_code = check_block_code($3);
451 			free($4);
452 		}
453 		| BLOCK RETURN NUM {
454 			(void) strlcpy(loc->block_fmt, "temporary failure",
455 			    sizeof(loc->block_fmt));
456 			loc->block_code = check_block_code($3);
457 			if ($3 >= 30 && $3 < 40)
458 				yyerror("missing `meta' for block return %d", $3);
459 		}
460 		| BLOCK {
461 			(void) strlcpy(loc->block_fmt, "temporary failure",
462 			    sizeof(loc->block_fmt));
463 			loc->block_code = 40;
464 		}
465 		| DEFAULT TYPE string {
466 			(void) strlcpy(loc->default_mime, $3,
467 			    sizeof(loc->default_mime));
468 			free($3);
469 		}
470 		| fastcgi
471 		| INDEX string {
472 			(void) strlcpy(loc->index, $2, sizeof(loc->index));
473 			free($2);
474 		}
475 		| LANG string {
476 			(void) strlcpy(loc->lang, $2,
477 			    sizeof(loc->lang));
478 			free($2);
479 		}
480 		| LOG bool	{ loc->disable_log = !$2; }
481 		| REQUIRE CLIENT CA string {
482 			ensure_absolute_path($4);
483 			loc->reqca_path = $4;
484 		}
485 		| ROOT string		{
486 			(void) strlcpy(loc->dir, $2, sizeof(loc->dir));
487 			free($2);
488 		}
489 		| STRIP NUM		{ loc->strip = check_strip_no($2); }
490 		;
491 
492 fastcgi		: FASTCGI '{' optnl fastcgiopts '}'
493 		| FASTCGI fastcgiopt
494 		| FASTCGI string {
495 			yywarn("`fastcgi path' is deprecated.  "
496 			    "Please use `fastcgi socket path' instead.");
497 			loc->fcgi = fastcgi_conf($2, NULL);
498 			free($2);
499 		}
500 		| error '}'
501 		;
502 
503 fastcgiopts	: /* empty */
504 		| fastcgiopts fastcgiopt optnl
505 		;
506 
507 fastcgiopt	: PARAM string '=' string {
508 			add_param($2, $4);
509 		}
510 		| SOCKET string {
511 			loc->fcgi = fastcgi_conf($2, NULL);
512 			free($2);
513 		}
514 		| SOCKET TCP string PORT NUM {
515 			char *c;
516 
517 			if (asprintf(&c, "%d", $5) == -1)
518 				fatal("asprintf");
519 			loc->fcgi = fastcgi_conf($3, c);
520 			free($3);
521 			free(c);
522 		}
523 		| SOCKET TCP string {
524 			loc->fcgi = fastcgi_conf($3, "9000");
525 		}
526 		| SOCKET TCP string PORT string {
527 			loc->fcgi = fastcgi_conf($3, $5);
528 			free($3);
529 			free($5);
530 		}
531 		;
532 
533 types		: TYPES '{' optnl mediaopts_l '}' ;
534 
535 mediaopts_l	: mediaopts_l mediaoptsl nl
536 		| mediaoptsl nl
537 		;
538 
539 mediaoptsl	: STRING {
540 			free(current_media);
541 			current_media = $1;
542 		} medianames_l optsemicolon
543 		| include
544 		;
545 
546 medianames_l	: medianames_l medianamesl
547 		| medianamesl
548 		;
549 
550 medianamesl	: numberstring {
551 			if (add_mime(&conf->mime, current_media, $1) == -1)
552 				fatal("add_mime");
553 			free($1);
554 		}
555 		;
556 
557 nl		: '\n' optnl
558 		;
559 
560 optnl		: '\n' optnl		/* zero or more newlines */
561 		| ';' optnl		/* semicolons too */
562 		| /*empty*/
563 		;
564 
565 optsemicolon	: ';'
566 		|
567 		;
568 
569 %%
570 
571 static const struct keyword {
572 	const char *word;
573 	int token;
574 } keywords[] = {
575 	/* these MUST be sorted */
576 	{"alias", ALIAS},
577 	{"auto", AUTO},
578 	{"block", BLOCK},
579 	{"ca", CA},
580 	{"cert", CERT},
581 	{"chroot", CHROOT},
582 	{"client", CLIENT},
583 	{"default", DEFAULT},
584 	{"fastcgi", FASTCGI},
585 	{"for-host", FOR_HOST},
586 	{"include", INCLUDE},
587 	{"index", INDEX},
588 	{"ipv6", IPV6},
589 	{"key", KEY},
590 	{"lang", LANG},
591 	{"listen", LISTEN},
592 	{"location", LOCATION},
593 	{"log", LOG},
594 	{"ocsp", OCSP},
595 	{"off", OFF},
596 	{"on", ON},
597 	{"param", PARAM},
598 	{"port", PORT},
599 	{"prefork", PREFORK},
600 	{"proto", PROTO},
601 	{"protocols", PROTOCOLS},
602 	{"proxy", PROXY},
603 	{"relay-to", RELAY_TO},
604 	{"require", REQUIRE},
605 	{"return", RETURN},
606 	{"root", ROOT},
607 	{"server", SERVER},
608 	{"sni", SNI},
609 	{"socket", SOCKET},
610 	{"strip", STRIP},
611 	{"tcp", TCP},
612 	{"to-ext", TOEXT},
613 	{"type", TYPE},
614 	{"types", TYPES},
615 	{"use-tls", USE_TLS},
616 	{"user", USER},
617 	{"verifyname", VERIFYNAME},
618 };
619 
620 void
621 yyerror(const char *msg, ...)
622 {
623 	va_list ap;
624 
625 	file->errors++;
626 
627 	va_start(ap, msg);
628 	fprintf(stderr, "%s:%d error: ", config_path, yylval.lineno);
629 	vfprintf(stderr, msg, ap);
630 	fprintf(stderr, "\n");
631 	va_end(ap);
632 }
633 
634 void
635 yywarn(const char *msg, ...)
636 {
637 	va_list ap;
638 
639 	va_start(ap, msg);
640 	fprintf(stderr, "%s:%d warning: ", config_path, yylval.lineno);
641 	vfprintf(stderr, msg, ap);
642 	fprintf(stderr, "\n");
643 	va_end(ap);
644 }
645 
646 int
647 kw_cmp(const void *k, const void *e)
648 {
649 	return strcmp(k, ((struct keyword *)e)->word);
650 }
651 
652 int
653 lookup(char *s)
654 {
655 	const struct keyword	*p;
656 
657 	p = bsearch(s, keywords, sizeof(keywords)/sizeof(keywords[0]),
658 	    sizeof(keywords[0]), kw_cmp);
659 
660 	if (p)
661 		return p->token;
662 	else
663 		return STRING;
664 }
665 
666 #define START_EXPAND	1
667 #define DONE_EXPAND	2
668 
669 static int	expanding;
670 
671 int
672 igetc(void)
673 {
674 	int	c;
675 
676 	while (1) {
677 		if (file->ungetpos > 0)
678 			c = file->ungetbuf[--file->ungetpos];
679 		else
680 			c = getc(file->stream);
681 
682 		if (c == START_EXPAND)
683 			expanding = 1;
684 		else if (c == DONE_EXPAND)
685 			expanding = 0;
686 		else
687 			break;
688 	}
689 	return c;
690 }
691 
692 int
693 lgetc(int quotec)
694 {
695 	int		c, next;
696 
697 	if (quotec) {
698 		if ((c = igetc()) == EOF) {
699 			yyerror("reached end of file while parsing "
700 			    "quoted string");
701 			if (file == topfile || popfile() == EOF)
702 				return EOF;
703 			return quotec;
704 		}
705 		return c;
706 	}
707 
708 	while ((c = igetc()) == '\\') {
709 		next = igetc();
710 		if (next != '\n') {
711 			c = next;
712 			break;
713 		}
714 		yylval.lineno = file->lineno;
715 		file->lineno++;
716 	}
717 
718 	if (c == EOF) {
719 		/*
720 		 * Fake EOL when hit EOF for the first time. This gets line
721 		 * count right if last line in included file is syntactically
722 		 * invalid and has no newline.
723 		 */
724 		if (file->eof_reached == 0) {
725 			file->eof_reached = 1;
726 			return '\n';
727 		}
728 		while (c == EOF) {
729 			if (file == topfile || popfile() == EOF)
730 				return EOF;
731 			c = igetc();
732 		}
733 	}
734 	return c;
735 }
736 
737 void
738 lungetc(int c)
739 {
740 	if (c == EOF)
741 		return;
742 
743 	if (file->ungetpos >= file->ungetsize) {
744 		void *p = reallocarray(file->ungetbuf, file->ungetsize, 2);
745 		if (p == NULL)
746 			fatal("lungetc");
747 		file->ungetbuf = p;
748 		file->ungetsize *= 2;
749 	}
750 	file->ungetbuf[file->ungetpos++] = c;
751 }
752 
753 int
754 findeol(void)
755 {
756 	int	c;
757 
758 	/* Skip to either EOF or the first real EOL. */
759 	while (1) {
760 		c = lgetc(0);
761 		if (c == '\n') {
762 			file->lineno++;
763 			break;
764 		}
765 		if (c == EOF)
766 			break;
767 	}
768 	return ERROR;
769 }
770 
771 int
772 yylex(void)
773 {
774 	char	 buf[8096];
775 	char	*p, *val;
776 	int	 quotec, next, c;
777 	int	 token;
778 
779 top:
780 	p = buf;
781 	while ((c = lgetc(0)) == ' ' || c == '\t')
782 		; /* nothing */
783 
784 	yylval.lineno = file->lineno;
785 	if (c == '#')
786 		while ((c = lgetc(0)) != '\n' && c != EOF)
787 			; /* nothing */
788 	if (c == '$' && !expanding) {
789 		while (1) {
790 			if ((c = lgetc(0)) == EOF)
791 				return 0;
792 			if (p + 1 >= buf + sizeof(buf) -1) {
793 				yyerror("string too long");
794 				return findeol();
795 			}
796 			if (isalnum(c) || c == '_') {
797 				*p++ = c;
798 				continue;
799 			}
800 			*p = '\0';
801 			lungetc(c);
802 			break;
803 		}
804 		val = symget(buf);
805 		if (val == NULL) {
806 			yyerror("macro `%s' not defined", buf);
807 			return findeol();
808 		}
809 		yylval.v.string = xstrdup(val);
810 		return STRING;
811 	}
812 	if (c == '@' && !expanding) {
813 		while (1) {
814 			if ((c = lgetc(0)) == EOF)
815 				return 0;
816 
817 			if (p + 1 >= buf + sizeof(buf) - 1) {
818 				yyerror("string too long");
819 				return findeol();
820 			}
821 			if (isalnum(c) || c == '_') {
822 				*p++ = c;
823 				continue;
824 			}
825 			*p = '\0';
826 			lungetc(c);
827 			break;
828 		}
829 		val = symget(buf);
830 		if (val == NULL) {
831 			yyerror("macro '%s' not defined", buf);
832 			return findeol();
833 		}
834 		p = val + strlen(val) - 1;
835 		lungetc(DONE_EXPAND);
836 		while (p >= val) {
837 			lungetc(*p);
838 			p--;
839 		}
840 		lungetc(START_EXPAND);
841 		goto top;
842 	}
843 
844 	switch (c) {
845 	case '\'':
846 	case '"':
847 		quotec = c;
848 		while (1) {
849 			if ((c = lgetc(quotec)) == EOF)
850 				return 0;
851 			if (c == '\n') {
852 				file->lineno++;
853 				continue;
854 			} else if (c == '\\') {
855 				if ((next = lgetc(quotec)) == EOF)
856 					return (0);
857 				if (next == quotec || next == ' ' ||
858 				    next == '\t')
859 					c = next;
860 				else if (next == '\n') {
861 					file->lineno++;
862 					continue;
863 				} else
864 					lungetc(next);
865 			} else if (c == quotec) {
866 				*p = '\0';
867 				break;
868 			} else if (c == '\0') {
869 				yyerror("invalid syntax");
870 				return findeol();
871 			}
872 			if (p + 1 >= buf + sizeof(buf) - 1) {
873 				yyerror("string too long");
874 				return findeol();
875 			}
876 			*p++ = c;
877 		}
878 		yylval.v.string = strdup(buf);
879 		if (yylval.v.string == NULL)
880 			fatal("yylex: strdup");
881 		return STRING;
882 	}
883 
884 #define allowed_to_end_number(x) \
885 	(isspace(x) || x == ')' || x ==',' || x == '/' || x == '}' || x == '=')
886 
887 	if (c == '-' || isdigit(c)) {
888 		do {
889 			*p++ = c;
890 			if ((size_t)(p-buf) >= sizeof(buf)) {
891 				yyerror("string too long");
892 				return findeol();
893 			}
894 		} while ((c = lgetc(0)) != EOF && isdigit(c));
895 		lungetc(c);
896 		if (p == buf + 1 && buf[0] == '-')
897 			goto nodigits;
898 		if (c == EOF || allowed_to_end_number(c)) {
899 			const char *errstr = NULL;
900 
901 			*p = '\0';
902 			yylval.v.number = strtonum(buf, LLONG_MIN,
903 			    LLONG_MAX, &errstr);
904 			if (errstr) {
905 				yyerror("\"%s\" invalid number: %s",
906 				    buf, errstr);
907 				return findeol();
908 			}
909 			return NUM;
910 		} else {
911 nodigits:
912 			while (p > buf + 1)
913 				lungetc(*--p);
914 			c = *--p;
915 			if (c == '-')
916 				return c;
917 		}
918 	}
919 
920 #define allowed_in_string(x) \
921 	(isalnum(x) || (ispunct(x) && x != '(' && x != ')' && \
922 	x != '{' && x != '}' && \
923 	x != '!' && x != '=' && x != '#' && \
924 	x != ',' && x != ';'))
925 
926 	if (isalnum(c) || c == ':' || c == '_') {
927 		do {
928 			*p++ = c;
929 			if ((size_t)(p-buf) >= sizeof(buf)) {
930 				yyerror("string too long");
931 				return findeol();
932 			}
933 		} while ((c = lgetc(0)) != EOF && (allowed_in_string(c)));
934 		lungetc(c);
935 		*p = '\0';
936 		if ((token = lookup(buf)) == STRING)
937 			yylval.v.string = xstrdup(buf);
938 		return token;
939 	}
940 	if (c == '\n') {
941 		yylval.lineno = file->lineno;
942 		file->lineno++;
943 	}
944 	if (c == EOF)
945 		return 0;
946 	return c;
947 }
948 
949 struct file *
950 pushfile(const char *name, int secret)
951 {
952 	struct file	*nfile;
953 
954 	nfile = xcalloc(1, sizeof(*nfile));
955 	nfile->name = xstrdup(name);
956 	if ((nfile->stream = fopen(nfile->name, "r")) == NULL) {
957 		log_warn("can't open %s", nfile->name);
958 		free(nfile->name);
959 		free(nfile);
960 		return NULL;
961 	}
962 	nfile->lineno = TAILQ_EMPTY(&files) ? 1 : 0;
963 	nfile->ungetsize = 16;
964 	nfile->ungetbuf = xcalloc(1, nfile->ungetsize);
965 	TAILQ_INSERT_TAIL(&files, nfile, entry);
966 	return nfile;
967 }
968 
969 int
970 popfile(void)
971 {
972 	struct file	*prev;
973 
974 	if ((prev = TAILQ_PREV(file, files, entry)) != NULL)
975 		prev->errors += file->errors;
976 
977 	TAILQ_REMOVE(&files, file, entry);
978 	fclose(file->stream);
979 	free(file->name);
980 	free(file->ungetbuf);
981 	free(file);
982 	file = prev;
983 	return file ? 0 : EOF;
984 }
985 
986 int
987 parse_conf(struct conf *c, const char *filename)
988 {
989 	struct sym		*sym, *next;
990 
991 	default_host = "*";
992 	default_port = 1965;
993 
994 	conf = c;
995 
996 	file = pushfile(filename, 0);
997 	if (file == NULL)
998 		return -1;
999 	topfile = file;
1000 
1001 	yyparse();
1002 	errors = file->errors;
1003 	popfile();
1004 
1005 	/* Free macros and check which have not been used. */
1006 	TAILQ_FOREACH_SAFE(sym, &symhead, entry, next) {
1007 		/* TODO: warn if !sym->used */
1008 		if (!sym->persist) {
1009 			free(sym->name);
1010 			free(sym->val);
1011 			TAILQ_REMOVE(&symhead, sym, entry);
1012 			free(sym);
1013 		}
1014 	}
1015 
1016 	if (errors)
1017 		return -1;
1018 	return 0;
1019 }
1020 
1021 int
1022 symset(const char *name, const char *val, int persist)
1023 {
1024 	struct sym *sym;
1025 
1026 	TAILQ_FOREACH(sym, &symhead, entry) {
1027 		if (!strcmp(name, sym->name))
1028 			break;
1029 	}
1030 
1031 	if (sym != NULL) {
1032 		if (sym->persist)
1033 			return 0;
1034 		else {
1035 			free(sym->name);
1036 			free(sym->val);
1037 			TAILQ_REMOVE(&symhead, sym, entry);
1038 			free(sym);
1039 		}
1040 	}
1041 
1042 	sym = xcalloc(1, sizeof(*sym));
1043 	sym->name = xstrdup(name);
1044 	sym->val = xstrdup(val);
1045 	sym->used = 0;
1046 	sym->persist = persist;
1047 
1048 	TAILQ_INSERT_TAIL(&symhead, sym, entry);
1049 	return 0;
1050 }
1051 
1052 int
1053 cmdline_symset(char *s)
1054 {
1055 	char	*sym, *val;
1056 	int	 ret;
1057 
1058 	if ((val = strrchr(s, '=')) == NULL)
1059 		return -1;
1060 	sym = xcalloc(1, val - s + 1);
1061 	memcpy(sym, s, val - s);
1062 	ret = symset(sym, val + 1, 1);
1063 	free(sym);
1064 	return ret;
1065 }
1066 
1067 char *
1068 symget(const char *nam)
1069 {
1070 	struct sym	*sym;
1071 
1072 	TAILQ_FOREACH(sym, &symhead, entry) {
1073 		if (strcmp(nam, sym->name) == 0) {
1074 			sym->used = 1;
1075 			return sym->val;
1076 		}
1077 	}
1078 	return NULL;
1079 }
1080 
1081 char *
1082 ensure_absolute_path(char *path)
1083 {
1084 	if (path == NULL || *path != '/')
1085 		yyerror("not an absolute path: %s", path);
1086 	return path;
1087 }
1088 
1089 int
1090 check_block_code(int n)
1091 {
1092 	if (n < 10 || n >= 70 || (n >= 20 && n <= 29))
1093 		yyerror("invalid block code %d", n);
1094 	return n;
1095 }
1096 
1097 char *
1098 check_block_fmt(char *fmt)
1099 {
1100 	char *s;
1101 
1102 	for (s = fmt; *s; ++s) {
1103 		if (*s != '%')
1104 			continue;
1105 		switch (*++s) {
1106 		case '%':
1107 		case 'p':
1108 		case 'q':
1109 		case 'P':
1110 		case 'N':
1111 			break;
1112 		default:
1113 			yyerror("invalid format specifier %%%c", *s);
1114 		}
1115 	}
1116 
1117 	return fmt;
1118 }
1119 
1120 int
1121 check_strip_no(int n)
1122 {
1123 	if (n <= 0)
1124 		yyerror("invalid strip number %d", n);
1125 	return n;
1126 }
1127 
1128 int
1129 check_port_num(int n)
1130 {
1131 	if (n <= 0 || n >= UINT16_MAX)
1132 		yyerror("port number is %s: %d",
1133 		    n <= 0 ? "too small" : "too large",
1134 		    n);
1135 	return n;
1136 }
1137 
1138 int
1139 check_prefork_num(int n)
1140 {
1141 	if (n <= 0 || n >= PROC_MAX_INSTANCES)
1142 		yyerror("invalid prefork number %d", n);
1143 	return n;
1144 }
1145 
1146 void
1147 advance_loc(void)
1148 {
1149 	loc = new_location();
1150 	TAILQ_INSERT_TAIL(&host->locations, loc, locations);
1151 }
1152 
1153 void
1154 advance_proxy(void)
1155 {
1156 	proxy = new_proxy();
1157 	TAILQ_INSERT_TAIL(&host->proxies, proxy, proxies);
1158 }
1159 
1160 void
1161 parsehp(char *str, char **host, const char **port, const char *def)
1162 {
1163 	char		*at;
1164 	const char	*errstr;
1165 
1166 	*host = str;
1167 
1168 	if ((at = strchr(str, ':')) != NULL) {
1169 		*at++ = '\0';
1170 		*port = at;
1171 	} else
1172 		*port = def;
1173 
1174 	strtonum(*port, 1, UINT16_MAX, &errstr);
1175 	if (errstr != NULL)
1176 		yyerror("port is %s: %s", errstr, *port);
1177 }
1178 
1179 int
1180 fastcgi_conf(const char *path, const char *port)
1181 {
1182 	struct fcgi	*f;
1183 	int		i = 0;
1184 
1185 	TAILQ_FOREACH(f, &conf->fcgi, fcgi) {
1186 		if (!strcmp(f->path, path) &&
1187 		    ((port == NULL && *f->port == '\0') ||
1188 		     !strcmp(f->port, port)))
1189 			return i;
1190 		++i;
1191 	}
1192 
1193 	f = xcalloc(1, sizeof(*f));
1194 	f->id = i;
1195 	(void)strlcpy(f->path, path, sizeof(f->path));
1196 	if (port != NULL)
1197 		(void)strlcpy(f->port, port, sizeof(f->port));
1198 	TAILQ_INSERT_TAIL(&conf->fcgi, f, fcgi);
1199 
1200 	return f->id;
1201 }
1202 
1203 void
1204 add_param(char *name, char *val)
1205 {
1206 	struct envlist *e;
1207 	struct envhead *h = &loc->params;
1208 
1209 	e = xcalloc(1, sizeof(*e));
1210 	(void) strlcpy(e->name, name, sizeof(e->name));
1211 	(void) strlcpy(e->value, val, sizeof(e->value));
1212 	TAILQ_INSERT_TAIL(h, e, envs);
1213 }
1214 
1215 int
1216 getservice(const char *n)
1217 {
1218 	struct servent	*s;
1219 	const char	*errstr;
1220 	long long	 llval;
1221 
1222 	llval = strtonum(n, 0, UINT16_MAX, &errstr);
1223 	if (errstr) {
1224 		s = getservbyname(n, "tcp");
1225 		if (s == NULL)
1226 			s = getservbyname(n, "udp");
1227 		if (s == NULL)
1228 			return (-1);
1229 		return (ntohs(s->s_port));
1230 	}
1231 
1232 	return ((unsigned short)llval);
1233 }
1234 
1235 static void
1236 add_to_addr_queue(struct addrhead *a, struct addrinfo *ai)
1237 {
1238 	struct address		*addr;
1239 	struct sockaddr_in	*sin;
1240 	struct sockaddr_in6	*sin6;
1241 
1242 	if (ai->ai_addrlen > sizeof(addr->ss))
1243 		fatalx("ai_addrlen larger than a sockaddr_storage");
1244 
1245 	TAILQ_FOREACH(addr, a, addrs) {
1246 		if (addr->ai_flags == ai->ai_flags &&
1247 		    addr->ai_family == ai->ai_family &&
1248 		    addr->ai_socktype == ai->ai_socktype &&
1249 		    addr->ai_protocol == ai->ai_protocol &&
1250 		    addr->slen == ai->ai_addrlen &&
1251 		    !memcmp(&addr->ss, ai->ai_addr, addr->slen))
1252 			return;
1253 	}
1254 
1255 	addr = xcalloc(1, sizeof(*addr));
1256 	addr->ai_flags = ai->ai_flags;
1257 	addr->ai_family = ai->ai_family;
1258 	addr->ai_socktype = ai->ai_socktype;
1259 	addr->ai_protocol = ai->ai_protocol;
1260 	addr->slen = ai->ai_addrlen;
1261 	memcpy(&addr->ss, ai->ai_addr, ai->ai_addrlen);
1262 
1263 	/* for commodity */
1264 	switch (addr->ai_family) {
1265 	case AF_INET:
1266 		sin = (struct sockaddr_in *)&addr->ss;
1267 		addr->port = ntohs(sin->sin_port);
1268 		break;
1269 	case AF_INET6:
1270 		sin6 = (struct sockaddr_in6 *)&addr->ss;
1271 		addr->port = ntohs(sin6->sin6_port);
1272 		break;
1273 	default:
1274 		fatalx("unknown socket family %d", addr->ai_family);
1275 	}
1276 
1277 	addr->sock = -1;
1278 
1279 	TAILQ_INSERT_HEAD(a, addr, addrs);
1280 }
1281 
1282 void
1283 listen_on(const char *hostname, const char *servname)
1284 {
1285 	struct addrinfo hints, *res, *res0;
1286 	int error;
1287 
1288 	memset(&hints, 0, sizeof(hints));
1289 	hints.ai_family = AF_UNSPEC;
1290 	hints.ai_socktype = SOCK_STREAM;
1291 	hints.ai_flags = AI_PASSIVE;
1292 	error = getaddrinfo(hostname, servname, &hints, &res0);
1293 	if (error) {
1294 		yyerror("listen on \"%s\" port %s: %s", hostname, servname,
1295 		    gai_strerror(errno));
1296 		return;
1297 	}
1298 
1299 	for (res = res0; res; res = res->ai_next) {
1300 		add_to_addr_queue(&host->addrs, res);
1301 		add_to_addr_queue(&conf->addrs, res);
1302 	}
1303 
1304 	freeaddrinfo(res0);
1305 }