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 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	: '*' { $$ = NULL; }
302 		| STRING
303 		;
304 
305 servopt		: ALIAS string {
306 			struct alist *a;
307 
308 			a = xcalloc(1, sizeof(*a));
309 			(void) strlcpy(a->alias, $2, sizeof(a->alias));
310 			free($2);
311 			TAILQ_INSERT_TAIL(&host->aliases, a, aliases);
312 		}
313 		| CERT string		{
314 			ensure_absolute_path($2);
315 			free(host->cert_path);
316 			host->cert_path = $2;
317 		}
318 		| KEY string		{
319 			ensure_absolute_path($2);
320 			free(host->key_path);
321 			host->key_path = $2;
322 		}
323 		| OCSP string		{
324 			ensure_absolute_path($2);
325 			free(host->ocsp_path);
326 			host->ocsp_path = $2;
327 		}
328 		| PARAM string '=' string {
329 			add_param($2, $4);
330 		}
331 		| LISTEN ON listen_addr PORT STRING {
332 			listen_on($3, $5);
333 			free($3);
334 			free($5);
335 		}
336 		| LISTEN ON listen_addr PORT NUM {
337 			char portno[32];
338 			int r;
339 
340 			r = snprintf(portno, sizeof(portno), "%d", $5);
341 			if (r < 0 || (size_t)r >= sizeof(portno))
342 				fatal("snprintf");
343 
344 			listen_on($3, portno);
345 			free($3);
346 		}
347 		| locopt
348 		;
349 
350 proxy		: PROXY { advance_proxy(); }
351 		  proxy_matches '{' optnl proxy_opts '}' {
352 			if (*proxy->host == '\0')
353 				yyerror("invalid proxy block: missing `relay-to' option");
354 
355 			if ((proxy->cert_path == NULL && proxy->key_path != NULL) ||
356 			    (proxy->cert_path != NULL && proxy->key_path == NULL))
357 				yyerror("invalid proxy block: missing cert or key");
358 		}
359 		;
360 
361 proxy_matches	: /* empty */
362 		| proxy_matches proxy_match
363 		;
364 
365 proxy_port	: /* empty */	{ $$ = 1965; }
366 		| PORT STRING {
367 			if (($$ = getservice($2)) == -1)
368 				yyerror("invalid port number %s", $2);
369 			free($2);
370 		}
371 		| PORT NUM	{ $$ = $2; }
372 		;
373 
374 proxy_match	: PROTO string {
375 			(void) strlcpy(proxy->match_proto, $2, sizeof(proxy->match_proto));
376 			free($2);
377 		}
378 		| FOR_HOST string proxy_port {
379 			(void) strlcpy(proxy->match_host, $2, sizeof(proxy->match_host));
380 			(void) snprintf(proxy->match_port, sizeof(proxy->match_port),
381 			    "%d", $3);
382 			free($2);
383 		}
384 		;
385 
386 proxy_opts	: /* empty */
387 		| proxy_opts proxy_opt optnl
388 		;
389 
390 proxy_opt	: CERT string {
391 			free(proxy->cert);
392 			ensure_absolute_path($2);
393 			proxy->cert_path = $2;
394 		}
395 		| KEY string {
396 			free(proxy->key);
397 			ensure_absolute_path($2);
398 			proxy->key_path = $2;
399 		}
400 		| PROTOCOLS string {
401 			if (tls_config_parse_protocols(&proxy->protocols, $2) == -1)
402 				yyerror("invalid protocols string \"%s\"", $2);
403 			free($2);
404 		}
405 		| RELAY_TO string proxy_port {
406 			(void) strlcpy(proxy->host, $2, sizeof(proxy->host));
407 			(void) snprintf(proxy->port, sizeof(proxy->port),
408 			    "%d", $3);
409 			free($2);
410 		}
411 		| REQUIRE CLIENT CA string {
412 			ensure_absolute_path($4);
413 			proxy->reqca_path = $4;
414 		}
415 		| SNI string {
416 			(void) strlcpy(proxy->sni, $2, sizeof(proxy->sni));
417 			free($2);
418 		}
419 		| USE_TLS bool {
420 			proxy->notls = !$2;
421 		}
422 		| VERIFYNAME bool {
423 			proxy->noverifyname = !$2;
424 		}
425 		;
426 
427 location	: LOCATION { advance_loc(); } string '{' optnl locopts '}' {
428 			/* drop the starting '/' if any */
429 			if (*$3 == '/')
430 				memmove($3, $3+1, strlen($3));
431 			(void) strlcpy(loc->match, $3, sizeof(loc->match));
432 			free($3);
433 		}
434 		| error '}'
435 		;
436 
437 locopts		: /* empty */
438 		| locopts locopt optnl
439 		;
440 
441 locopt		: AUTO INDEX bool	{ loc->auto_index = $3 ? 1 : -1; }
442 		| BLOCK RETURN NUM string {
443 			check_block_fmt($4);
444 			(void) strlcpy(loc->block_fmt, $4, sizeof(loc->block_fmt));
445 			loc->block_code = check_block_code($3);
446 			free($4);
447 		}
448 		| BLOCK RETURN NUM {
449 			(void) strlcpy(loc->block_fmt, "temporary failure",
450 			    sizeof(loc->block_fmt));
451 			loc->block_code = check_block_code($3);
452 			if ($3 >= 30 && $3 < 40)
453 				yyerror("missing `meta' for block return %d", $3);
454 		}
455 		| BLOCK {
456 			(void) strlcpy(loc->block_fmt, "temporary failure",
457 			    sizeof(loc->block_fmt));
458 			loc->block_code = 40;
459 		}
460 		| DEFAULT TYPE string {
461 			(void) strlcpy(loc->default_mime, $3,
462 			    sizeof(loc->default_mime));
463 			free($3);
464 		}
465 		| FASTCGI fastcgi
466 		| INDEX string {
467 			(void) strlcpy(loc->index, $2, sizeof(loc->index));
468 			free($2);
469 		}
470 		| LANG string {
471 			(void) strlcpy(loc->lang, $2,
472 			    sizeof(loc->lang));
473 			free($2);
474 		}
475 		| LOG bool	{ loc->disable_log = !$2; }
476 		| REQUIRE CLIENT CA string {
477 			ensure_absolute_path($4);
478 			loc->reqca_path = $4;
479 		}
480 		| ROOT string		{
481 			(void) strlcpy(loc->dir, $2, sizeof(loc->dir));
482 			free($2);
483 		}
484 		| STRIP NUM		{ loc->strip = check_strip_no($2); }
485 		;
486 
487 fastcgi		: string {
488 			loc->fcgi = fastcgi_conf($1, NULL);
489 			free($1);
490 		}
491 		| TCP string PORT NUM {
492 			char *c;
493 			if (asprintf(&c, "%d", $4) == -1)
494 				fatal("asprintf");
495 			loc->fcgi = fastcgi_conf($2, c);
496 			free($2);
497 		}
498 		| TCP string {
499 			loc->fcgi = fastcgi_conf($2, "9000");
500 			free($2);
501 		}
502 		| TCP string PORT string {
503 			loc->fcgi = fastcgi_conf($2, $4);
504 			free($2);
505 			free($4);
506 		}
507 		;
508 
509 types		: TYPES '{' optnl mediaopts_l '}' ;
510 
511 mediaopts_l	: mediaopts_l mediaoptsl nl
512 		| mediaoptsl nl
513 		;
514 
515 mediaoptsl	: STRING {
516 			free(current_media);
517 			current_media = $1;
518 		} medianames_l optsemicolon
519 		| include
520 		;
521 
522 medianames_l	: medianames_l medianamesl
523 		| medianamesl
524 		;
525 
526 medianamesl	: numberstring {
527 			if (add_mime(&conf->mime, current_media, $1) == -1)
528 				fatal("add_mime");
529 			free($1);
530 		}
531 		;
532 
533 nl		: '\n' optnl
534 		;
535 
536 optnl		: '\n' optnl		/* zero or more newlines */
537 		| ';' optnl		/* semicolons too */
538 		| /*empty*/
539 		;
540 
541 optsemicolon	: ';'
542 		|
543 		;
544 
545 %%
546 
547 static const struct keyword {
548 	const char *word;
549 	int token;
550 } keywords[] = {
551 	/* these MUST be sorted */
552 	{"alias", ALIAS},
553 	{"auto", AUTO},
554 	{"block", BLOCK},
555 	{"ca", CA},
556 	{"cert", CERT},
557 	{"chroot", CHROOT},
558 	{"client", CLIENT},
559 	{"default", DEFAULT},
560 	{"fastcgi", FASTCGI},
561 	{"for-host", FOR_HOST},
562 	{"include", INCLUDE},
563 	{"index", INDEX},
564 	{"ipv6", IPV6},
565 	{"key", KEY},
566 	{"lang", LANG},
567 	{"listen", LISTEN},
568 	{"location", LOCATION},
569 	{"log", LOG},
570 	{"ocsp", OCSP},
571 	{"off", OFF},
572 	{"on", ON},
573 	{"param", PARAM},
574 	{"port", PORT},
575 	{"prefork", PREFORK},
576 	{"proto", PROTO},
577 	{"protocols", PROTOCOLS},
578 	{"proxy", PROXY},
579 	{"relay-to", RELAY_TO},
580 	{"require", REQUIRE},
581 	{"return", RETURN},
582 	{"root", ROOT},
583 	{"server", SERVER},
584 	{"sni", SNI},
585 	{"strip", STRIP},
586 	{"tcp", TCP},
587 	{"to-ext", TOEXT},
588 	{"type", TYPE},
589 	{"types", TYPES},
590 	{"use-tls", USE_TLS},
591 	{"user", USER},
592 	{"verifyname", VERIFYNAME},
593 };
594 
595 void
596 yyerror(const char *msg, ...)
597 {
598 	va_list ap;
599 
600 	file->errors++;
601 
602 	va_start(ap, msg);
603 	fprintf(stderr, "%s:%d error: ", config_path, yylval.lineno);
604 	vfprintf(stderr, msg, ap);
605 	fprintf(stderr, "\n");
606 	va_end(ap);
607 }
608 
609 void
610 yywarn(const char *msg, ...)
611 {
612 	va_list ap;
613 
614 	va_start(ap, msg);
615 	fprintf(stderr, "%s:%d warning: ", config_path, yylval.lineno);
616 	vfprintf(stderr, msg, ap);
617 	fprintf(stderr, "\n");
618 	va_end(ap);
619 }
620 
621 int
622 kw_cmp(const void *k, const void *e)
623 {
624 	return strcmp(k, ((struct keyword *)e)->word);
625 }
626 
627 int
628 lookup(char *s)
629 {
630 	const struct keyword	*p;
631 
632 	p = bsearch(s, keywords, sizeof(keywords)/sizeof(keywords[0]),
633 	    sizeof(keywords[0]), kw_cmp);
634 
635 	if (p)
636 		return p->token;
637 	else
638 		return STRING;
639 }
640 
641 #define START_EXPAND	1
642 #define DONE_EXPAND	2
643 
644 static int	expanding;
645 
646 int
647 igetc(void)
648 {
649 	int	c;
650 
651 	while (1) {
652 		if (file->ungetpos > 0)
653 			c = file->ungetbuf[--file->ungetpos];
654 		else
655 			c = getc(file->stream);
656 
657 		if (c == START_EXPAND)
658 			expanding = 1;
659 		else if (c == DONE_EXPAND)
660 			expanding = 0;
661 		else
662 			break;
663 	}
664 	return c;
665 }
666 
667 int
668 lgetc(int quotec)
669 {
670 	int		c, next;
671 
672 	if (quotec) {
673 		if ((c = igetc()) == EOF) {
674 			yyerror("reached end of file while parsing "
675 			    "quoted string");
676 			if (file == topfile || popfile() == EOF)
677 				return EOF;
678 			return quotec;
679 		}
680 		return c;
681 	}
682 
683 	while ((c = igetc()) == '\\') {
684 		next = igetc();
685 		if (next != '\n') {
686 			c = next;
687 			break;
688 		}
689 		yylval.lineno = file->lineno;
690 		file->lineno++;
691 	}
692 
693 	if (c == EOF) {
694 		/*
695 		 * Fake EOL when hit EOF for the first time. This gets line
696 		 * count right if last line in included file is syntactically
697 		 * invalid and has no newline.
698 		 */
699 		if (file->eof_reached == 0) {
700 			file->eof_reached = 1;
701 			return '\n';
702 		}
703 		while (c == EOF) {
704 			if (file == topfile || popfile() == EOF)
705 				return EOF;
706 			c = igetc();
707 		}
708 	}
709 	return c;
710 }
711 
712 void
713 lungetc(int c)
714 {
715 	if (c == EOF)
716 		return;
717 
718 	if (file->ungetpos >= file->ungetsize) {
719 		void *p = reallocarray(file->ungetbuf, file->ungetsize, 2);
720 		if (p == NULL)
721 			fatal("lungetc");
722 		file->ungetbuf = p;
723 		file->ungetsize *= 2;
724 	}
725 	file->ungetbuf[file->ungetpos++] = c;
726 }
727 
728 int
729 findeol(void)
730 {
731 	int	c;
732 
733 	/* Skip to either EOF or the first real EOL. */
734 	while (1) {
735 		c = lgetc(0);
736 		if (c == '\n') {
737 			file->lineno++;
738 			break;
739 		}
740 		if (c == EOF)
741 			break;
742 	}
743 	return ERROR;
744 }
745 
746 int
747 yylex(void)
748 {
749 	char	 buf[8096];
750 	char	*p, *val;
751 	int	 quotec, next, c;
752 	int	 token;
753 
754 top:
755 	p = buf;
756 	while ((c = lgetc(0)) == ' ' || c == '\t')
757 		; /* nothing */
758 
759 	yylval.lineno = file->lineno;
760 	if (c == '#')
761 		while ((c = lgetc(0)) != '\n' && c != EOF)
762 			; /* nothing */
763 	if (c == '$' && !expanding) {
764 		while (1) {
765 			if ((c = lgetc(0)) == EOF)
766 				return 0;
767 			if (p + 1 >= buf + sizeof(buf) -1) {
768 				yyerror("string too long");
769 				return findeol();
770 			}
771 			if (isalnum(c) || c == '_') {
772 				*p++ = c;
773 				continue;
774 			}
775 			*p = '\0';
776 			lungetc(c);
777 			break;
778 		}
779 		val = symget(buf);
780 		if (val == NULL) {
781 			yyerror("macro `%s' not defined", buf);
782 			return findeol();
783 		}
784 		yylval.v.string = xstrdup(val);
785 		return STRING;
786 	}
787 	if (c == '@' && !expanding) {
788 		while (1) {
789 			if ((c = lgetc(0)) == EOF)
790 				return 0;
791 
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 		p = val + strlen(val) - 1;
810 		lungetc(DONE_EXPAND);
811 		while (p >= val) {
812 			lungetc(*p);
813 			p--;
814 		}
815 		lungetc(START_EXPAND);
816 		goto top;
817 	}
818 
819 	switch (c) {
820 	case '\'':
821 	case '"':
822 		quotec = c;
823 		while (1) {
824 			if ((c = lgetc(quotec)) == EOF)
825 				return 0;
826 			if (c == '\n') {
827 				file->lineno++;
828 				continue;
829 			} else if (c == '\\') {
830 				if ((next = lgetc(quotec)) == EOF)
831 					return (0);
832 				if (next == quotec || next == ' ' ||
833 				    next == '\t')
834 					c = next;
835 				else if (next == '\n') {
836 					file->lineno++;
837 					continue;
838 				} else
839 					lungetc(next);
840 			} else if (c == quotec) {
841 				*p = '\0';
842 				break;
843 			} else if (c == '\0') {
844 				yyerror("invalid syntax");
845 				return findeol();
846 			}
847 			if (p + 1 >= buf + sizeof(buf) - 1) {
848 				yyerror("string too long");
849 				return findeol();
850 			}
851 			*p++ = c;
852 		}
853 		yylval.v.string = strdup(buf);
854 		if (yylval.v.string == NULL)
855 			fatal("yylex: strdup");
856 		return STRING;
857 	}
858 
859 #define allowed_to_end_number(x) \
860 	(isspace(x) || x == ')' || x ==',' || x == '/' || x == '}' || x == '=')
861 
862 	if (c == '-' || isdigit(c)) {
863 		do {
864 			*p++ = c;
865 			if ((size_t)(p-buf) >= sizeof(buf)) {
866 				yyerror("string too long");
867 				return findeol();
868 			}
869 		} while ((c = lgetc(0)) != EOF && isdigit(c));
870 		lungetc(c);
871 		if (p == buf + 1 && buf[0] == '-')
872 			goto nodigits;
873 		if (c == EOF || allowed_to_end_number(c)) {
874 			const char *errstr = NULL;
875 
876 			*p = '\0';
877 			yylval.v.number = strtonum(buf, LLONG_MIN,
878 			    LLONG_MAX, &errstr);
879 			if (errstr) {
880 				yyerror("\"%s\" invalid number: %s",
881 				    buf, errstr);
882 				return findeol();
883 			}
884 			return NUM;
885 		} else {
886 nodigits:
887 			while (p > buf + 1)
888 				lungetc(*--p);
889 			c = *--p;
890 			if (c == '-')
891 				return c;
892 		}
893 	}
894 
895 #define allowed_in_string(x) \
896 	(isalnum(x) || (ispunct(x) && x != '(' && x != ')' && \
897 	x != '{' && x != '}' && \
898 	x != '!' && x != '=' && x != '#' && \
899 	x != ',' && x != ';'))
900 
901 	if (isalnum(c) || c == ':' || c == '_') {
902 		do {
903 			*p++ = c;
904 			if ((size_t)(p-buf) >= sizeof(buf)) {
905 				yyerror("string too long");
906 				return findeol();
907 			}
908 		} while ((c = lgetc(0)) != EOF && (allowed_in_string(c)));
909 		lungetc(c);
910 		*p = '\0';
911 		if ((token = lookup(buf)) == STRING)
912 			yylval.v.string = xstrdup(buf);
913 		return token;
914 	}
915 	if (c == '\n') {
916 		yylval.lineno = file->lineno;
917 		file->lineno++;
918 	}
919 	if (c == EOF)
920 		return 0;
921 	return c;
922 }
923 
924 struct file *
925 pushfile(const char *name, int secret)
926 {
927 	struct file	*nfile;
928 
929 	nfile = xcalloc(1, sizeof(*nfile));
930 	nfile->name = xstrdup(name);
931 	if ((nfile->stream = fopen(nfile->name, "r")) == NULL) {
932 		log_warn("can't open %s", nfile->name);
933 		free(nfile->name);
934 		free(nfile);
935 		return NULL;
936 	}
937 	nfile->lineno = TAILQ_EMPTY(&files) ? 1 : 0;
938 	nfile->ungetsize = 16;
939 	nfile->ungetbuf = xcalloc(1, nfile->ungetsize);
940 	TAILQ_INSERT_TAIL(&files, nfile, entry);
941 	return nfile;
942 }
943 
944 int
945 popfile(void)
946 {
947 	struct file	*prev;
948 
949 	if ((prev = TAILQ_PREV(file, files, entry)) != NULL)
950 		prev->errors += file->errors;
951 
952 	TAILQ_REMOVE(&files, file, entry);
953 	fclose(file->stream);
954 	free(file->name);
955 	free(file->ungetbuf);
956 	free(file);
957 	file = prev;
958 	return file ? 0 : EOF;
959 }
960 
961 int
962 parse_conf(struct conf *c, const char *filename)
963 {
964 	struct sym		*sym, *next;
965 
966 	default_host = "*";
967 	default_port = 1965;
968 
969 	conf = c;
970 
971 	file = pushfile(filename, 0);
972 	if (file == NULL)
973 		return -1;
974 	topfile = file;
975 
976 	yyparse();
977 	errors = file->errors;
978 	popfile();
979 
980 	/* Free macros and check which have not been used. */
981 	TAILQ_FOREACH_SAFE(sym, &symhead, entry, next) {
982 		/* TODO: warn if !sym->used */
983 		if (!sym->persist) {
984 			free(sym->name);
985 			free(sym->val);
986 			TAILQ_REMOVE(&symhead, sym, entry);
987 			free(sym);
988 		}
989 	}
990 
991 	if (errors)
992 		return -1;
993 	return 0;
994 }
995 
996 int
997 symset(const char *name, const char *val, int persist)
998 {
999 	struct sym *sym;
1000 
1001 	TAILQ_FOREACH(sym, &symhead, entry) {
1002 		if (!strcmp(name, sym->name))
1003 			break;
1004 	}
1005 
1006 	if (sym != NULL) {
1007 		if (sym->persist)
1008 			return 0;
1009 		else {
1010 			free(sym->name);
1011 			free(sym->val);
1012 			TAILQ_REMOVE(&symhead, sym, entry);
1013 			free(sym);
1014 		}
1015 	}
1016 
1017 	sym = xcalloc(1, sizeof(*sym));
1018 	sym->name = xstrdup(name);
1019 	sym->val = xstrdup(val);
1020 	sym->used = 0;
1021 	sym->persist = persist;
1022 
1023 	TAILQ_INSERT_TAIL(&symhead, sym, entry);
1024 	return 0;
1025 }
1026 
1027 int
1028 cmdline_symset(char *s)
1029 {
1030 	char	*sym, *val;
1031 	int	 ret;
1032 
1033 	if ((val = strrchr(s, '=')) == NULL)
1034 		return -1;
1035 	sym = xcalloc(1, val - s + 1);
1036 	memcpy(sym, s, val - s);
1037 	ret = symset(sym, val + 1, 1);
1038 	free(sym);
1039 	return ret;
1040 }
1041 
1042 char *
1043 symget(const char *nam)
1044 {
1045 	struct sym	*sym;
1046 
1047 	TAILQ_FOREACH(sym, &symhead, entry) {
1048 		if (strcmp(nam, sym->name) == 0) {
1049 			sym->used = 1;
1050 			return sym->val;
1051 		}
1052 	}
1053 	return NULL;
1054 }
1055 
1056 char *
1057 ensure_absolute_path(char *path)
1058 {
1059 	if (path == NULL || *path != '/')
1060 		yyerror("not an absolute path: %s", path);
1061 	return path;
1062 }
1063 
1064 int
1065 check_block_code(int n)
1066 {
1067 	if (n < 10 || n >= 70 || (n >= 20 && n <= 29))
1068 		yyerror("invalid block code %d", n);
1069 	return n;
1070 }
1071 
1072 char *
1073 check_block_fmt(char *fmt)
1074 {
1075 	char *s;
1076 
1077 	for (s = fmt; *s; ++s) {
1078 		if (*s != '%')
1079 			continue;
1080 		switch (*++s) {
1081 		case '%':
1082 		case 'p':
1083 		case 'q':
1084 		case 'P':
1085 		case 'N':
1086 			break;
1087 		default:
1088 			yyerror("invalid format specifier %%%c", *s);
1089 		}
1090 	}
1091 
1092 	return fmt;
1093 }
1094 
1095 int
1096 check_strip_no(int n)
1097 {
1098 	if (n <= 0)
1099 		yyerror("invalid strip number %d", n);
1100 	return n;
1101 }
1102 
1103 int
1104 check_port_num(int n)
1105 {
1106 	if (n <= 0 || n >= UINT16_MAX)
1107 		yyerror("port number is %s: %d",
1108 		    n <= 0 ? "too small" : "too large",
1109 		    n);
1110 	return n;
1111 }
1112 
1113 int
1114 check_prefork_num(int n)
1115 {
1116 	if (n <= 0 || n >= PROC_MAX_INSTANCES)
1117 		yyerror("invalid prefork number %d", n);
1118 	return n;
1119 }
1120 
1121 void
1122 advance_loc(void)
1123 {
1124 	loc = new_location();
1125 	TAILQ_INSERT_TAIL(&host->locations, loc, locations);
1126 }
1127 
1128 void
1129 advance_proxy(void)
1130 {
1131 	proxy = new_proxy();
1132 	TAILQ_INSERT_TAIL(&host->proxies, proxy, proxies);
1133 }
1134 
1135 void
1136 parsehp(char *str, char **host, const char **port, const char *def)
1137 {
1138 	char		*at;
1139 	const char	*errstr;
1140 
1141 	*host = str;
1142 
1143 	if ((at = strchr(str, ':')) != NULL) {
1144 		*at++ = '\0';
1145 		*port = at;
1146 	} else
1147 		*port = def;
1148 
1149 	strtonum(*port, 1, UINT16_MAX, &errstr);
1150 	if (errstr != NULL)
1151 		yyerror("port is %s: %s", errstr, *port);
1152 }
1153 
1154 int
1155 fastcgi_conf(const char *path, const char *port)
1156 {
1157 	struct fcgi	*f;
1158 	int		i = 0;
1159 
1160 	TAILQ_FOREACH(f, &conf->fcgi, fcgi) {
1161 		if (!strcmp(f->path, path) &&
1162 		    ((port == NULL && *f->port == '\0') ||
1163 		     !strcmp(f->port, port)))
1164 			return i;
1165 		++i;
1166 	}
1167 
1168 	f = xcalloc(1, sizeof(*f));
1169 	f->id = i;
1170 	(void)strlcpy(f->path, path, sizeof(f->path));
1171 	if (port != NULL)
1172 		(void)strlcpy(f->port, port, sizeof(f->port));
1173 	TAILQ_INSERT_TAIL(&conf->fcgi, f, fcgi);
1174 
1175 	return f->id;
1176 }
1177 
1178 void
1179 add_param(char *name, char *val)
1180 {
1181 	struct envlist *e;
1182 	struct envhead *h = &host->params;
1183 
1184 	e = xcalloc(1, sizeof(*e));
1185 	(void) strlcpy(e->name, name, sizeof(e->name));
1186 	(void) strlcpy(e->value, val, sizeof(e->value));
1187 	TAILQ_INSERT_TAIL(h, e, envs);
1188 }
1189 
1190 int
1191 getservice(const char *n)
1192 {
1193 	struct servent	*s;
1194 	const char	*errstr;
1195 	long long	 llval;
1196 
1197 	llval = strtonum(n, 0, UINT16_MAX, &errstr);
1198 	if (errstr) {
1199 		s = getservbyname(n, "tcp");
1200 		if (s == NULL)
1201 			s = getservbyname(n, "udp");
1202 		if (s == NULL)
1203 			return (-1);
1204 		return (ntohs(s->s_port));
1205 	}
1206 
1207 	return ((unsigned short)llval);
1208 }
1209 
1210 static void
1211 add_to_addr_queue(struct addrhead *a, struct addrinfo *ai)
1212 {
1213 	struct address		*addr;
1214 	struct sockaddr_in	*sin;
1215 	struct sockaddr_in6	*sin6;
1216 
1217 	if (ai->ai_addrlen > sizeof(addr->ss))
1218 		fatalx("ai_addrlen larger than a sockaddr_storage");
1219 
1220 	TAILQ_FOREACH(addr, a, addrs) {
1221 		if (addr->ai_flags == ai->ai_flags &&
1222 		    addr->ai_family == ai->ai_family &&
1223 		    addr->ai_socktype == ai->ai_socktype &&
1224 		    addr->ai_protocol == ai->ai_protocol &&
1225 		    addr->slen == ai->ai_addrlen &&
1226 		    !memcmp(&addr->ss, ai->ai_addr, addr->slen))
1227 			return;
1228 	}
1229 
1230 	addr = xcalloc(1, sizeof(*addr));
1231 	addr->ai_flags = ai->ai_flags;
1232 	addr->ai_family = ai->ai_family;
1233 	addr->ai_socktype = ai->ai_socktype;
1234 	addr->ai_protocol = ai->ai_protocol;
1235 	addr->slen = ai->ai_addrlen;
1236 	memcpy(&addr->ss, ai->ai_addr, ai->ai_addrlen);
1237 
1238 	/* for commodity */
1239 	switch (addr->ai_family) {
1240 	case AF_INET:
1241 		sin = (struct sockaddr_in *)&addr->ss;
1242 		addr->port = ntohs(sin->sin_port);
1243 		break;
1244 	case AF_INET6:
1245 		sin6 = (struct sockaddr_in6 *)&addr->ss;
1246 		addr->port = ntohs(sin6->sin6_port);
1247 		break;
1248 	default:
1249 		fatalx("unknown socket family %d", addr->ai_family);
1250 	}
1251 
1252 	addr->sock = -1;
1253 
1254 	TAILQ_INSERT_HEAD(a, addr, addrs);
1255 }
1256 
1257 void
1258 listen_on(const char *hostname, const char *servname)
1259 {
1260 	struct addrinfo hints, *res, *res0;
1261 	int error;
1262 
1263 	memset(&hints, 0, sizeof(hints));
1264 	hints.ai_family = AF_UNSPEC;
1265 	hints.ai_socktype = SOCK_STREAM;
1266 	hints.ai_flags = AI_PASSIVE;
1267 	error = getaddrinfo(hostname, servname, &hints, &res0);
1268 	if (error) {
1269 		yyerror("listen on \"%s\" port %s: %s", hostname, servname,
1270 		    gai_strerror(errno));
1271 		return;
1272 	}
1273 
1274 	for (res = res0; res; res = res->ai_next) {
1275 		add_to_addr_queue(&host->addrs, res);
1276 		add_to_addr_queue(&conf->addrs, res);
1277 	}
1278 
1279 	freeaddrinfo(res0);
1280 }