1 /*
2  * Copyright (c) 2022 Stefan Sperling <stsp@openbsd.org>
3  * Copyright (c) 2016-2019, 2020-2021 Tracey Emery <tracey@traceyemery.net>
4  * Copyright (c) 2004, 2005 Esben Norby <norby@openbsd.org>
5  * Copyright (c) 2004 Ryan McBride <mcbride@openbsd.org>
6  * Copyright (c) 2002, 2003, 2004 Henning Brauer <henning@openbsd.org>
7  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
8  * Copyright (c) 2001 Daniel Hartmeier.  All rights reserved.
9  * Copyright (c) 2001 Theo de Raadt.  All rights reserved.
10  *
11  * Permission to use, copy, modify, and distribute this software for any
12  * purpose with or without fee is hereby granted, provided that the above
13  * copyright notice and this permission notice appear in all copies.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
16  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
17  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
18  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
19  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
20  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
21  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
22  */
23 
24 %{
25 #include <sys/time.h>
26 #include <sys/types.h>
27 #include <sys/queue.h>
28 #include <sys/stat.h>
29 
30 #include <ctype.h>
31 #include <err.h>
32 #include <errno.h>
33 #include <event.h>
34 #include <imsg.h>
35 #include <limits.h>
36 #include <sha1.h>
37 #include <stdarg.h>
38 #include <stdlib.h>
39 #include <stdio.h>
40 #include <string.h>
41 #include <syslog.h>
42 #include <unistd.h>
43 
44 #include "got_error.h"
45 #include "got_path.h"
46 
47 #include "log.h"
48 #include "gotd.h"
49 #include "auth.h"
50 #include "listen.h"
51 
52 TAILQ_HEAD(files, file)		 files = TAILQ_HEAD_INITIALIZER(files);
53 static struct file {
54 	TAILQ_ENTRY(file)	 entry;
55 	FILE			*stream;
56 	char			*name;
57 	int			 lineno;
58 	int			 errors;
59 } *file;
60 struct file	*newfile(const char *, int);
61 static void	 closefile(struct file *);
62 int		 check_file_secrecy(int, const char *);
63 int		 yyparse(void);
64 int		 yylex(void);
65 int		 yyerror(const char *, ...)
66     __attribute__((__format__ (printf, 1, 2)))
67     __attribute__((__nonnull__ (1)));
68 int		 kw_cmp(const void *, const void *);
69 int		 lookup(char *);
70 int		 lgetc(int);
71 int		 lungetc(int);
72 int		 findeol(void);
73 
74 TAILQ_HEAD(symhead, sym)	 symhead = TAILQ_HEAD_INITIALIZER(symhead);
75 struct sym {
76 	TAILQ_ENTRY(sym)	 entry;
77 	int			 used;
78 	int			 persist;
79 	char			*nam;
80 	char			*val;
81 };
82 
83 int	 symset(const char *, const char *, int);
84 char	*symget(const char *);
85 
86 static int		 errors;
87 
88 static struct gotd		*gotd;
89 static struct gotd_repo		*new_repo;
90 static int			 conf_limit_user_connections(const char *, int);
91 static struct gotd_repo		*conf_new_repo(const char *);
92 static void			 conf_new_access_rule(struct gotd_repo *,
93 				    enum gotd_access, int, char *);
94 static enum gotd_procid		 gotd_proc_id;
95 
96 typedef struct {
97 	union {
98 		long long	 number;
99 		char		*string;
100 		struct timeval	 tv;
101 	} v;
102 	int lineno;
103 } YYSTYPE;
104 
105 %}
106 
107 %token	PATH ERROR ON UNIX_SOCKET UNIX_GROUP USER REPOSITORY PERMIT DENY
108 %token	RO RW CONNECTION LIMIT REQUEST TIMEOUT
109 
110 %token	<v.string>	STRING
111 %token	<v.number>	NUMBER
112 %type	<v.number>	boolean
113 %type	<v.tv>		timeout
114 
115 %%
116 
117 grammar		:
118 		| grammar '\n'
119 		| grammar main '\n'
120 		| grammar repository '\n'
121 		;
122 
123 boolean		: STRING {
124 			if (strcasecmp($1, "1") == 0 ||
125 			    strcasecmp($1, "yes") == 0 ||
126 			    strcasecmp($1, "on") == 0)
127 				$$ = 1;
128 			else if (strcasecmp($1, "0") == 0 ||
129 			    strcasecmp($1, "off") == 0 ||
130 			    strcasecmp($1, "no") == 0)
131 				$$ = 0;
132 			else {
133 				yyerror("invalid boolean value '%s'", $1);
134 				free($1);
135 				YYERROR;
136 			}
137 			free($1);
138 		}
139 		| ON { $$ = 1; }
140 		| NUMBER { $$ = $1; }
141 		;
142 
143 timeout		: NUMBER {
144 			if ($1 < 0) {
145 				yyerror("invalid timeout: %lld", $1);
146 				YYERROR;
147 			}
148 			$$.tv_sec = $1;
149 			$$.tv_usec = 0;
150 		}
151 		| STRING {
152 			const char	*errstr;
153 			const char	*type = "seconds";
154 			size_t		 len;
155 			int		 mul = 1;
156 
157 			if (*$1 == '\0') {
158 				yyerror("invalid number of seconds: %s", $1);
159 				free($1);
160 				YYERROR;
161 			}
162 
163 			len = strlen($1);
164 			switch ($1[len - 1]) {
165 			case 'S':
166 			case 's':
167 				$1[len - 1] = '\0';
168 				break;
169 			case 'M':
170 			case 'm':
171 				type = "minutes";
172 				mul = 60;
173 				$1[len - 1] = '\0';
174 				break;
175 			case 'H':
176 			case 'h':
177 				type = "hours";
178 				mul = 60 * 60;
179 				$1[len - 1] = '\0';
180 				break;
181 			}
182 
183 			$$.tv_usec = 0;
184 			$$.tv_sec = strtonum($1, 0, INT_MAX / mul, &errstr);
185 			if (errstr) {
186 				yyerror("number of %s is %s: %s", type,
187 				    errstr, $1);
188 				free($1);
189 				YYERROR;
190 			}
191 
192 			$$.tv_sec *= mul;
193 			free($1);
194 		}
195 		;
196 
197 main		: UNIX_SOCKET STRING {
198 			if (gotd_proc_id == PROC_LISTEN) {
199 				if (strlcpy(gotd->unix_socket_path, $2,
200 				    sizeof(gotd->unix_socket_path)) >=
201 				    sizeof(gotd->unix_socket_path)) {
202 					yyerror("%s: unix socket path too long",
203 					    __func__);
204 					free($2);
205 					YYERROR;
206 				}
207 			}
208 			free($2);
209 		}
210 		| UNIX_GROUP STRING {
211 			if (strlcpy(gotd->unix_group_name, $2,
212 			    sizeof(gotd->unix_group_name)) >=
213 			    sizeof(gotd->unix_group_name)) {
214 				yyerror("%s: unix group name too long",
215 				    __func__);
216 				free($2);
217 				YYERROR;
218 			}
219 			free($2);
220 		}
221 		| USER STRING {
222 			if (strlcpy(gotd->user_name, $2,
223 			    sizeof(gotd->user_name)) >=
224 			    sizeof(gotd->user_name)) {
225 				yyerror("%s: user name too long", __func__);
226 				free($2);
227 				YYERROR;
228 			}
229 			free($2);
230 		}
231 		| connection
232 		;
233 
234 connection	: CONNECTION '{' optnl conflags_l '}'
235 		| CONNECTION conflags
236 
237 conflags_l	: conflags optnl conflags_l
238 		| conflags optnl
239 		;
240 
241 conflags	: REQUEST TIMEOUT timeout		{
242 			if ($3.tv_sec <= 0) {
243 				yyerror("invalid timeout: %lld", $3.tv_sec);
244 				YYERROR;
245 			}
246 			memcpy(&gotd->request_timeout, &$3,
247 			    sizeof(gotd->request_timeout));
248 		}
249 		| LIMIT USER STRING NUMBER	{
250 			if (gotd_proc_id == PROC_LISTEN &&
251 			    conf_limit_user_connections($3, $4) == -1) {
252 				free($3);
253 				YYERROR;
254 			}
255 			free($3);
256 		}
257 		;
258 
259 repository	: REPOSITORY STRING {
260 			struct gotd_repo *repo;
261 
262 			TAILQ_FOREACH(repo, &gotd->repos, entry) {
263 				if (strcmp(repo->name, $2) == 0) {
264 					yyerror("duplicate repository '%s'", $2);
265 					free($2);
266 					YYERROR;
267 				}
268 			}
269 
270 			if (gotd_proc_id == PROC_GOTD ||
271 			    gotd_proc_id == PROC_AUTH) {
272 				new_repo = conf_new_repo($2);
273 			}
274 			free($2);
275 		} '{' optnl repoopts2 '}' {
276 		}
277 		;
278 
279 repoopts1	: PATH STRING {
280 			if (gotd_proc_id == PROC_GOTD ||
281 			    gotd_proc_id == PROC_AUTH) {
282 				if (!got_path_is_absolute($2)) {
283 					yyerror("%s: path %s is not absolute",
284 					    __func__, $2);
285 					free($2);
286 					YYERROR;
287 				}
288 				if (strlcpy(new_repo->path, $2,
289 				    sizeof(new_repo->path)) >=
290 				    sizeof(new_repo->path)) {
291 					yyerror("%s: path truncated", __func__);
292 					free($2);
293 					YYERROR;
294 				}
295 			}
296 			free($2);
297 		}
298 		| PERMIT RO STRING {
299 			if (gotd_proc_id == PROC_AUTH) {
300 				conf_new_access_rule(new_repo,
301 				    GOTD_ACCESS_PERMITTED, GOTD_AUTH_READ, $3);
302 			}
303 		}
304 		| PERMIT RW STRING {
305 			if (gotd_proc_id == PROC_AUTH) {
306 				conf_new_access_rule(new_repo,
307 				    GOTD_ACCESS_PERMITTED,
308 				    GOTD_AUTH_READ | GOTD_AUTH_WRITE, $3);
309 			}
310 		}
311 		| DENY STRING {
312 			if (gotd_proc_id == PROC_AUTH) {
313 				conf_new_access_rule(new_repo,
314 				    GOTD_ACCESS_DENIED, 0, $2);
315 			}
316 		}
317 		;
318 
319 repoopts2	: repoopts2 repoopts1 nl
320 		| repoopts1 optnl
321 		;
322 
323 nl		: '\n' optnl
324 		;
325 
326 optnl		: '\n' optnl		/* zero or more newlines */
327 		| /* empty */
328 		;
329 
330 %%
331 
332 struct keywords {
333 	const char	*k_name;
334 	int		 k_val;
335 };
336 
337 int
338 yyerror(const char *fmt, ...)
339 {
340 	va_list ap;
341 	char *msg;
342 
343 	file->errors++;
344 	va_start(ap, fmt);
345 	if (vasprintf(&msg, fmt, ap) == -1)
346 		fatalx("yyerror vasprintf");
347 	va_end(ap);
348 	logit(LOG_CRIT, "%s:%d: %s", file->name, yylval.lineno, msg);
349 	free(msg);
350 	return (0);
351 }
352 
353 int
354 kw_cmp(const void *k, const void *e)
355 {
356 	return (strcmp(k, ((const struct keywords *)e)->k_name));
357 }
358 
359 int
360 lookup(char *s)
361 {
362 	/* This has to be sorted always. */
363 	static const struct keywords keywords[] = {
364 		{ "connection",			CONNECTION },
365 		{ "deny",			DENY },
366 		{ "limit",			LIMIT },
367 		{ "on",				ON },
368 		{ "path",			PATH },
369 		{ "permit",			PERMIT },
370 		{ "repository",			REPOSITORY },
371 		{ "request",			REQUEST },
372 		{ "ro",				RO },
373 		{ "rw",				RW },
374 		{ "timeout",			TIMEOUT },
375 		{ "unix_group",			UNIX_GROUP },
376 		{ "unix_socket",		UNIX_SOCKET },
377 		{ "user",			USER },
378 	};
379 	const struct keywords *p;
380 
381 	p = bsearch(s, keywords, sizeof(keywords)/sizeof(keywords[0]),
382 	    sizeof(keywords[0]), kw_cmp);
383 
384 	if (p)
385 		return (p->k_val);
386 	else
387 		return (STRING);
388 }
389 
390 #define MAXPUSHBACK	128
391 
392 unsigned char *parsebuf;
393 int parseindex;
394 unsigned char pushback_buffer[MAXPUSHBACK];
395 int pushback_index = 0;
396 
397 int
398 lgetc(int quotec)
399 {
400 	int c, next;
401 
402 	if (parsebuf) {
403 		/* Read character from the parsebuffer instead of input. */
404 		if (parseindex >= 0) {
405 			c = parsebuf[parseindex++];
406 			if (c != '\0')
407 				return (c);
408 			parsebuf = NULL;
409 		} else
410 			parseindex++;
411 	}
412 
413 	if (pushback_index)
414 		return (pushback_buffer[--pushback_index]);
415 
416 	if (quotec) {
417 		c = getc(file->stream);
418 		if (c == EOF)
419 			yyerror("reached end of file while parsing "
420 			    "quoted string");
421 		return (c);
422 	}
423 
424 	c = getc(file->stream);
425 	while (c == '\\') {
426 		next = getc(file->stream);
427 		if (next != '\n') {
428 			c = next;
429 			break;
430 		}
431 		yylval.lineno = file->lineno;
432 		file->lineno++;
433 		c = getc(file->stream);
434 	}
435 
436 	return (c);
437 }
438 
439 int
440 lungetc(int c)
441 {
442 	if (c == EOF)
443 		return (EOF);
444 	if (parsebuf) {
445 		parseindex--;
446 		if (parseindex >= 0)
447 			return (c);
448 	}
449 	if (pushback_index < MAXPUSHBACK-1)
450 		return (pushback_buffer[pushback_index++] = c);
451 	else
452 		return (EOF);
453 }
454 
455 int
456 findeol(void)
457 {
458 	int c;
459 
460 	parsebuf = NULL;
461 
462 	/* Skip to either EOF or the first real EOL. */
463 	while (1) {
464 		if (pushback_index)
465 			c = pushback_buffer[--pushback_index];
466 		else
467 			c = lgetc(0);
468 		if (c == '\n') {
469 			file->lineno++;
470 			break;
471 		}
472 		if (c == EOF)
473 			break;
474 	}
475 	return (ERROR);
476 }
477 
478 int
479 yylex(void)
480 {
481 	unsigned char buf[8096];
482 	unsigned char *p, *val;
483 	int quotec, next, c;
484 	int token;
485 
486 top:
487 	p = buf;
488 	c = lgetc(0);
489 	while (c == ' ' || c == '\t')
490 		c = lgetc(0); /* nothing */
491 
492 	yylval.lineno = file->lineno;
493 	if (c == '#') {
494 		c = lgetc(0);
495 		while (c != '\n' && c != EOF)
496 			c = lgetc(0); /* nothing */
497 	}
498 	if (c == '$' && parsebuf == NULL) {
499 		while (1) {
500 			c = lgetc(0);
501 			if (c == EOF)
502 				return (0);
503 
504 			if (p + 1 >= buf + sizeof(buf) - 1) {
505 				yyerror("string too long");
506 				return (findeol());
507 			}
508 			if (isalnum(c) || c == '_') {
509 				*p++ = c;
510 				continue;
511 			}
512 			*p = '\0';
513 			lungetc(c);
514 			break;
515 		}
516 		val = symget(buf);
517 		if (val == NULL) {
518 			yyerror("macro '%s' not defined", buf);
519 			return (findeol());
520 		}
521 		parsebuf = val;
522 		parseindex = 0;
523 		goto top;
524 	}
525 
526 	switch (c) {
527 	case '\'':
528 	case '"':
529 		quotec = c;
530 		while (1) {
531 			c = lgetc(quotec);
532 			if (c == EOF)
533 				return (0);
534 			if (c == '\n') {
535 				file->lineno++;
536 				continue;
537 			} else if (c == '\\') {
538 				next = lgetc(quotec);
539 				if (next == EOF)
540 					return (0);
541 				if (next == quotec || c == ' ' || c == '\t')
542 					c = next;
543 				else if (next == '\n') {
544 					file->lineno++;
545 					continue;
546 				} else
547 					lungetc(next);
548 			} else if (c == quotec) {
549 				*p = '\0';
550 				break;
551 			} else if (c == '\0') {
552 				yyerror("syntax error");
553 				return (findeol());
554 			}
555 			if (p + 1 >= buf + sizeof(buf) - 1) {
556 				yyerror("string too long");
557 				return (findeol());
558 			}
559 			*p++ = c;
560 		}
561 		yylval.v.string = strdup(buf);
562 		if (yylval.v.string == NULL)
563 			err(1, "yylex: strdup");
564 		return (STRING);
565 	}
566 
567 #define allowed_to_end_number(x) \
568 	(isspace(x) || x == ')' || x ==',' || x == '/' || x == '}' || x == '=')
569 
570 	if (c == '-' || isdigit(c)) {
571 		do {
572 			*p++ = c;
573 			if ((unsigned)(p-buf) >= sizeof(buf)) {
574 				yyerror("string too long");
575 				return (findeol());
576 			}
577 			c = lgetc(0);
578 		} while (c != EOF && isdigit(c));
579 		lungetc(c);
580 		if (p == buf + 1 && buf[0] == '-')
581 			goto nodigits;
582 		if (c == EOF || allowed_to_end_number(c)) {
583 			const char *errstr = NULL;
584 
585 			*p = '\0';
586 			yylval.v.number = strtonum(buf, LLONG_MIN,
587 			    LLONG_MAX, &errstr);
588 			if (errstr) {
589 				yyerror("\"%s\" invalid number: %s",
590 				    buf, errstr);
591 				return (findeol());
592 			}
593 			return (NUMBER);
594 		} else {
595 nodigits:
596 			while (p > buf + 1)
597 				lungetc(*--p);
598 			c = *--p;
599 			if (c == '-')
600 				return (c);
601 		}
602 	}
603 
604 #define allowed_in_string(x) \
605 	(isalnum(x) || (ispunct(x) && x != '(' && x != ')' && \
606 	x != '{' && x != '}' && \
607 	x != '!' && x != '=' && x != '#' && \
608 	x != ','))
609 
610 	if (isalnum(c) || c == ':' || c == '_') {
611 		do {
612 			*p++ = c;
613 			if ((unsigned)(p-buf) >= sizeof(buf)) {
614 				yyerror("string too long");
615 				return (findeol());
616 			}
617 			c = lgetc(0);
618 		} while (c != EOF && (allowed_in_string(c)));
619 		lungetc(c);
620 		*p = '\0';
621 		token = lookup(buf);
622 		if (token == STRING) {
623 			yylval.v.string = strdup(buf);
624 			if (yylval.v.string == NULL)
625 				err(1, "yylex: strdup");
626 		}
627 		return (token);
628 	}
629 	if (c == '\n') {
630 		yylval.lineno = file->lineno;
631 		file->lineno++;
632 	}
633 	if (c == EOF)
634 		return (0);
635 	return (c);
636 }
637 
638 int
639 check_file_secrecy(int fd, const char *fname)
640 {
641 	struct stat st;
642 
643 	if (fstat(fd, &st)) {
644 		log_warn("cannot stat %s", fname);
645 		return (-1);
646 	}
647 	if (st.st_uid != 0 && st.st_uid != getuid()) {
648 		log_warnx("%s: owner not root or current user", fname);
649 		return (-1);
650 	}
651 	if (st.st_mode & (S_IWGRP | S_IXGRP | S_IRWXO)) {
652 		log_warnx("%s: group writable or world read/writable", fname);
653 		return (-1);
654 	}
655 	return (0);
656 }
657 
658 struct file *
659 newfile(const char *name, int secret)
660 {
661 	struct file *nfile;
662 
663 	nfile = calloc(1, sizeof(struct file));
664 	if (nfile == NULL) {
665 		log_warn("calloc");
666 		return (NULL);
667 	}
668 	nfile->name = strdup(name);
669 	if (nfile->name == NULL) {
670 		log_warn("strdup");
671 		free(nfile);
672 		return (NULL);
673 	}
674 	nfile->stream = fopen(nfile->name, "r");
675 	if (nfile->stream == NULL) {
676 		/* no warning, we don't require a conf file */
677 		free(nfile->name);
678 		free(nfile);
679 		return (NULL);
680 	} else if (secret &&
681 	    check_file_secrecy(fileno(nfile->stream), nfile->name)) {
682 		fclose(nfile->stream);
683 		free(nfile->name);
684 		free(nfile);
685 		return (NULL);
686 	}
687 	nfile->lineno = 1;
688 	return (nfile);
689 }
690 
691 static void
692 closefile(struct file *xfile)
693 {
694 	fclose(xfile->stream);
695 	free(xfile->name);
696 	free(xfile);
697 }
698 
699 int
700 parse_config(const char *filename, enum gotd_procid proc_id,
701     struct gotd *env)
702 {
703 	struct sym *sym, *next;
704 	struct gotd_repo *repo;
705 
706 	memset(env, 0, sizeof(*env));
707 
708 	gotd = env;
709 	gotd_proc_id = proc_id;
710 	TAILQ_INIT(&gotd->repos);
711 
712 	/* Apply default values. */
713 	if (strlcpy(gotd->unix_socket_path, GOTD_UNIX_SOCKET,
714 	    sizeof(gotd->unix_socket_path)) >= sizeof(gotd->unix_socket_path)) {
715 		fprintf(stderr, "%s: unix socket path too long", __func__);
716 		return -1;
717 	}
718 	if (strlcpy(gotd->unix_group_name, GOTD_UNIX_GROUP,
719 	    sizeof(gotd->unix_group_name)) >= sizeof(gotd->unix_group_name)) {
720 		fprintf(stderr, "%s: unix group name too long", __func__);
721 		return -1;
722 	}
723 	if (strlcpy(gotd->user_name, GOTD_USER,
724 	    sizeof(gotd->user_name)) >= sizeof(gotd->user_name)) {
725 		fprintf(stderr, "%s: user name too long", __func__);
726 		return -1;
727 	}
728 
729 	gotd->request_timeout.tv_sec = GOTD_DEFAULT_REQUEST_TIMEOUT;
730 	gotd->request_timeout.tv_usec = 0;
731 
732 	file = newfile(filename, 0);
733 	if (file == NULL) {
734 		/* just return, as we don't require a conf file */
735 		return (0);
736 	}
737 
738 	yyparse();
739 	errors = file->errors;
740 	closefile(file);
741 
742 	/* Free macros and check which have not been used. */
743 	TAILQ_FOREACH_SAFE(sym, &symhead, entry, next) {
744 		if ((gotd->verbosity > 1) && !sym->used)
745 			fprintf(stderr, "warning: macro '%s' not used\n",
746 			    sym->nam);
747 		if (!sym->persist) {
748 			free(sym->nam);
749 			free(sym->val);
750 			TAILQ_REMOVE(&symhead, sym, entry);
751 			free(sym);
752 		}
753 	}
754 
755 	if (errors)
756 		return (-1);
757 
758 	TAILQ_FOREACH(repo, &gotd->repos, entry) {
759 		if (repo->path[0] == '\0') {
760 			log_warnx("repository \"%s\": no path provided in "
761 			    "configuration file", repo->name);
762 			return (-1);
763 		}
764 	}
765 
766 	return (0);
767 }
768 
769 static int
770 uid_connection_limit_cmp(const void *pa, const void *pb)
771 {
772 	const struct gotd_uid_connection_limit *a = pa, *b = pb;
773 
774 	if (a->uid < b->uid)
775 		return -1;
776 	else if (a->uid > b->uid);
777 		return 1;
778 
779 	return 0;
780 }
781 
782 static int
783 conf_limit_user_connections(const char *user, int maximum)
784 {
785 	uid_t uid;
786 	struct gotd_uid_connection_limit *limit;
787 	size_t nlimits;
788 
789 	if (maximum < 1) {
790 		yyerror("max connections cannot be smaller 1");
791 		return -1;
792 	}
793 	if (maximum > GOTD_MAXCLIENTS) {
794 		yyerror("max connections must be <= %d", GOTD_MAXCLIENTS);
795 		return -1;
796 	}
797 
798 	if (gotd_auth_parseuid(user, &uid) == -1) {
799 		yyerror("%s: no such user", user);
800 		return -1;
801 	}
802 
803 	limit = gotd_find_uid_connection_limit(gotd->connection_limits,
804 	    gotd->nconnection_limits, uid);
805 	if (limit) {
806 		limit->max_connections = maximum;
807 		return 0;
808 	}
809 
810 	limit = gotd->connection_limits;
811 	nlimits = gotd->nconnection_limits + 1;
812 	limit = reallocarray(limit, nlimits, sizeof(*limit));
813 	if (limit == NULL)
814 		fatal("reallocarray");
815 
816 	limit[nlimits - 1].uid = uid;
817 	limit[nlimits - 1].max_connections = maximum;
818 
819 	gotd->connection_limits = limit;
820 	gotd->nconnection_limits = nlimits;
821 	qsort(gotd->connection_limits, gotd->nconnection_limits,
822 	    sizeof(gotd->connection_limits[0]), uid_connection_limit_cmp);
823 
824 	return 0;
825 }
826 
827 static struct gotd_repo *
828 conf_new_repo(const char *name)
829 {
830 	struct gotd_repo *repo;
831 
832 	if (name[0] == '\0') {
833 		fatalx("syntax error: empty repository name found in %s",
834 		    file->name);
835 	}
836 
837 	if (strchr(name, '\n') != NULL)
838 		fatalx("repository names must not contain linefeeds: %s", name);
839 
840 	repo = calloc(1, sizeof(*repo));
841 	if (repo == NULL)
842 		fatalx("%s: calloc", __func__);
843 
844 	STAILQ_INIT(&repo->rules);
845 
846 	if (strlcpy(repo->name, name, sizeof(repo->name)) >=
847 	    sizeof(repo->name))
848 		fatalx("%s: strlcpy", __func__);
849 
850 	TAILQ_INSERT_TAIL(&gotd->repos, repo, entry);
851 	gotd->nrepos++;
852 
853 	return repo;
854 };
855 
856 static void
857 conf_new_access_rule(struct gotd_repo *repo, enum gotd_access access,
858     int authorization, char *identifier)
859 {
860 	struct gotd_access_rule *rule;
861 
862 	rule = calloc(1, sizeof(*rule));
863 	if (rule == NULL)
864 		fatal("calloc");
865 
866 	rule->access = access;
867 	rule->authorization = authorization;
868 	rule->identifier = identifier;
869 
870 	STAILQ_INSERT_TAIL(&repo->rules, rule, entry);
871 }
872 
873 int
874 symset(const char *nam, const char *val, int persist)
875 {
876 	struct sym *sym;
877 
878 	TAILQ_FOREACH(sym, &symhead, entry) {
879 		if (strcmp(nam, sym->nam) == 0)
880 			break;
881 	}
882 
883 	if (sym != NULL) {
884 		if (sym->persist == 1)
885 			return (0);
886 		else {
887 			free(sym->nam);
888 			free(sym->val);
889 			TAILQ_REMOVE(&symhead, sym, entry);
890 			free(sym);
891 		}
892 	}
893 	sym = calloc(1, sizeof(*sym));
894 	if (sym == NULL)
895 		return (-1);
896 
897 	sym->nam = strdup(nam);
898 	if (sym->nam == NULL) {
899 		free(sym);
900 		return (-1);
901 	}
902 	sym->val = strdup(val);
903 	if (sym->val == NULL) {
904 		free(sym->nam);
905 		free(sym);
906 		return (-1);
907 	}
908 	sym->used = 0;
909 	sym->persist = persist;
910 	TAILQ_INSERT_TAIL(&symhead, sym, entry);
911 	return (0);
912 }
913 
914 char *
915 symget(const char *nam)
916 {
917 	struct sym *sym;
918 
919 	TAILQ_FOREACH(sym, &symhead, entry) {
920 		if (strcmp(nam, sym->nam) == 0) {
921 			sym->used = 1;
922 			return (sym->val);
923 		}
924 	}
925 	return (NULL);
926 }