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 <stdarg.h>
37 #include <stdlib.h>
38 #include <stdio.h>
39 #include <string.h>
40 #include <syslog.h>
41 #include <unistd.h>
42 
43 #include "got_error.h"
44 #include "got_path.h"
45 #include "got_reference.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, 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 int			 conf_protect_ref_namespace(
95 				    struct got_pathlist_head *, char *);
96 static int			 conf_protect_tag_namespace(struct gotd_repo *,
97 				    char *);
98 static int			 conf_protect_branch_namespace(
99 				    struct gotd_repo *, char *);
100 static int			 conf_protect_branch(struct gotd_repo *,
101 				    char *);
102 static enum gotd_procid		 gotd_proc_id;
103 
104 typedef struct {
105 	union {
106 		long long	 number;
107 		char		*string;
108 		struct timeval	 tv;
109 	} v;
110 	int lineno;
111 } YYSTYPE;
112 
113 %}
114 
115 %token	PATH ERROR LISTEN ON USER REPOSITORY PERMIT DENY
116 %token	RO RW CONNECTION LIMIT REQUEST TIMEOUT
117 %token	PROTECT NAMESPACE BRANCH TAG
118 
119 %token	<v.string>	STRING
120 %token	<v.number>	NUMBER
121 %type	<v.tv>		timeout
122 
123 %%
124 
125 grammar		:
126 		| grammar '\n'
127 		| grammar main '\n'
128 		| grammar repository '\n'
129 		;
130 
131 timeout		: NUMBER {
132 			if ($1 < 0) {
133 				yyerror("invalid timeout: %lld", $1);
134 				YYERROR;
135 			}
136 			$$.tv_sec = $1;
137 			$$.tv_usec = 0;
138 		}
139 		| STRING {
140 			const char	*errstr;
141 			const char	*type = "seconds";
142 			size_t		 len;
143 			int		 mul = 1;
144 
145 			if (*$1 == '\0') {
146 				yyerror("invalid number of seconds: %s", $1);
147 				free($1);
148 				YYERROR;
149 			}
150 
151 			len = strlen($1);
152 			switch ($1[len - 1]) {
153 			case 'S':
154 			case 's':
155 				$1[len - 1] = '\0';
156 				break;
157 			case 'M':
158 			case 'm':
159 				type = "minutes";
160 				mul = 60;
161 				$1[len - 1] = '\0';
162 				break;
163 			case 'H':
164 			case 'h':
165 				type = "hours";
166 				mul = 60 * 60;
167 				$1[len - 1] = '\0';
168 				break;
169 			}
170 
171 			$$.tv_usec = 0;
172 			$$.tv_sec = strtonum($1, 0, INT_MAX / mul, &errstr);
173 			if (errstr) {
174 				yyerror("number of %s is %s: %s", type,
175 				    errstr, $1);
176 				free($1);
177 				YYERROR;
178 			}
179 
180 			$$.tv_sec *= mul;
181 			free($1);
182 		}
183 		;
184 
185 main		: LISTEN ON STRING {
186 			if (!got_path_is_absolute($3))
187 				yyerror("bad unix socket path \"%s\": "
188 				    "must be an absolute path", $3);
189 
190 			if (gotd_proc_id == PROC_LISTEN) {
191 				if (strlcpy(gotd->unix_socket_path, $3,
192 				    sizeof(gotd->unix_socket_path)) >=
193 				    sizeof(gotd->unix_socket_path)) {
194 					yyerror("%s: unix socket path too long",
195 					    __func__);
196 					free($3);
197 					YYERROR;
198 				}
199 			}
200 			free($3);
201 		}
202 		| USER STRING {
203 			if (strlcpy(gotd->user_name, $2,
204 			    sizeof(gotd->user_name)) >=
205 			    sizeof(gotd->user_name)) {
206 				yyerror("%s: user name too long", __func__);
207 				free($2);
208 				YYERROR;
209 			}
210 			free($2);
211 		}
212 		| connection
213 		;
214 
215 connection	: CONNECTION '{' optnl conflags_l '}'
216 		| CONNECTION conflags
217 
218 conflags_l	: conflags optnl conflags_l
219 		| conflags optnl
220 		;
221 
222 conflags	: REQUEST TIMEOUT timeout		{
223 			if ($3.tv_sec <= 0) {
224 				yyerror("invalid timeout: %lld", $3.tv_sec);
225 				YYERROR;
226 			}
227 			memcpy(&gotd->request_timeout, &$3,
228 			    sizeof(gotd->request_timeout));
229 		}
230 		| LIMIT USER STRING NUMBER	{
231 			if (gotd_proc_id == PROC_LISTEN &&
232 			    conf_limit_user_connections($3, $4) == -1) {
233 				free($3);
234 				YYERROR;
235 			}
236 			free($3);
237 		}
238 		;
239 
240 protect		: PROTECT '{' optnl protectflags_l '}'
241 		| PROTECT protectflags
242 
243 protectflags_l	: protectflags optnl protectflags_l
244 		| protectflags optnl
245 		;
246 
247 protectflags	: TAG NAMESPACE STRING {
248 			if (gotd_proc_id == PROC_GOTD ||
249 			    gotd_proc_id == PROC_REPO_WRITE) {
250 				if (conf_protect_tag_namespace(new_repo, $3)) {
251 					free($3);
252 					YYERROR;
253 				}
254 			}
255 		}
256 		| BRANCH NAMESPACE STRING {
257 			if (gotd_proc_id == PROC_GOTD ||
258 			    gotd_proc_id == PROC_REPO_WRITE) {
259 				if (conf_protect_branch_namespace(new_repo,
260 				    $3)) {
261 					free($3);
262 					YYERROR;
263 				}
264 				free($3);
265 			}
266 		}
267 		| BRANCH STRING {
268 			if (gotd_proc_id == PROC_GOTD ||
269 			    gotd_proc_id == PROC_REPO_WRITE) {
270 				if (conf_protect_branch(new_repo, $2)) {
271 					free($2);
272 					YYERROR;
273 				}
274 			}
275 		}
276 		;
277 
278 repository	: REPOSITORY STRING {
279 			struct gotd_repo *repo;
280 
281 			TAILQ_FOREACH(repo, &gotd->repos, entry) {
282 				if (strcmp(repo->name, $2) == 0) {
283 					yyerror("duplicate repository '%s'", $2);
284 					free($2);
285 					YYERROR;
286 				}
287 			}
288 
289 			if (gotd_proc_id == PROC_GOTD ||
290 			    gotd_proc_id == PROC_AUTH ||
291 			    gotd_proc_id == PROC_REPO_WRITE) {
292 				new_repo = conf_new_repo($2);
293 			}
294 			free($2);
295 		} '{' optnl repoopts2 '}' {
296 		}
297 		;
298 
299 repoopts1	: PATH STRING {
300 			if (gotd_proc_id == PROC_GOTD ||
301 			    gotd_proc_id == PROC_AUTH ||
302 			    gotd_proc_id == PROC_REPO_WRITE) {
303 				if (!got_path_is_absolute($2)) {
304 					yyerror("%s: path %s is not absolute",
305 					    __func__, $2);
306 					free($2);
307 					YYERROR;
308 				}
309 				if (realpath($2, new_repo->path) == NULL) {
310 					yyerror("realpath %s: %s", $2, strerror(errno));
311 					free($2);
312 					YYERROR;
313 				}
314 			}
315 			free($2);
316 		}
317 		| PERMIT RO STRING {
318 			if (gotd_proc_id == PROC_AUTH) {
319 				conf_new_access_rule(new_repo,
320 				    GOTD_ACCESS_PERMITTED, GOTD_AUTH_READ, $3);
321 			}
322 		}
323 		| PERMIT RW STRING {
324 			if (gotd_proc_id == PROC_AUTH) {
325 				conf_new_access_rule(new_repo,
326 				    GOTD_ACCESS_PERMITTED,
327 				    GOTD_AUTH_READ | GOTD_AUTH_WRITE, $3);
328 			}
329 		}
330 		| DENY STRING {
331 			if (gotd_proc_id == PROC_AUTH) {
332 				conf_new_access_rule(new_repo,
333 				    GOTD_ACCESS_DENIED, 0, $2);
334 			}
335 		}
336 		| protect
337 		;
338 
339 repoopts2	: repoopts2 repoopts1 nl
340 		| repoopts1 optnl
341 		;
342 
343 nl		: '\n' optnl
344 		;
345 
346 optnl		: '\n' optnl		/* zero or more newlines */
347 		| /* empty */
348 		;
349 
350 %%
351 
352 struct keywords {
353 	const char	*k_name;
354 	int		 k_val;
355 };
356 
357 int
358 yyerror(const char *fmt, ...)
359 {
360 	va_list ap;
361 	char *msg;
362 
363 	file->errors++;
364 	va_start(ap, fmt);
365 	if (vasprintf(&msg, fmt, ap) == -1)
366 		fatalx("yyerror vasprintf");
367 	va_end(ap);
368 	logit(LOG_CRIT, "%s:%d: %s", file->name, yylval.lineno, msg);
369 	free(msg);
370 	return (0);
371 }
372 
373 int
374 kw_cmp(const void *k, const void *e)
375 {
376 	return (strcmp(k, ((const struct keywords *)e)->k_name));
377 }
378 
379 int
380 lookup(char *s)
381 {
382 	/* This has to be sorted always. */
383 	static const struct keywords keywords[] = {
384 		{ "branch",			BRANCH },
385 		{ "connection",			CONNECTION },
386 		{ "deny",			DENY },
387 		{ "limit",			LIMIT },
388 		{ "listen",			LISTEN },
389 		{ "namespace",			NAMESPACE },
390 		{ "on",				ON },
391 		{ "path",			PATH },
392 		{ "permit",			PERMIT },
393 		{ "protect",			PROTECT },
394 		{ "repository",			REPOSITORY },
395 		{ "request",			REQUEST },
396 		{ "ro",				RO },
397 		{ "rw",				RW },
398 		{ "tag",			TAG },
399 		{ "timeout",			TIMEOUT },
400 		{ "user",			USER },
401 	};
402 	const struct keywords *p;
403 
404 	p = bsearch(s, keywords, sizeof(keywords)/sizeof(keywords[0]),
405 	    sizeof(keywords[0]), kw_cmp);
406 
407 	if (p)
408 		return (p->k_val);
409 	else
410 		return (STRING);
411 }
412 
413 #define MAXPUSHBACK	128
414 
415 unsigned char *parsebuf;
416 int parseindex;
417 unsigned char pushback_buffer[MAXPUSHBACK];
418 int pushback_index = 0;
419 
420 int
421 lgetc(int quotec)
422 {
423 	int c, next;
424 
425 	if (parsebuf) {
426 		/* Read character from the parsebuffer instead of input. */
427 		if (parseindex >= 0) {
428 			c = parsebuf[parseindex++];
429 			if (c != '\0')
430 				return (c);
431 			parsebuf = NULL;
432 		} else
433 			parseindex++;
434 	}
435 
436 	if (pushback_index)
437 		return (pushback_buffer[--pushback_index]);
438 
439 	if (quotec) {
440 		c = getc(file->stream);
441 		if (c == EOF)
442 			yyerror("reached end of file while parsing "
443 			    "quoted string");
444 		return (c);
445 	}
446 
447 	c = getc(file->stream);
448 	while (c == '\\') {
449 		next = getc(file->stream);
450 		if (next != '\n') {
451 			c = next;
452 			break;
453 		}
454 		yylval.lineno = file->lineno;
455 		file->lineno++;
456 		c = getc(file->stream);
457 	}
458 
459 	return (c);
460 }
461 
462 int
463 lungetc(int c)
464 {
465 	if (c == EOF)
466 		return (EOF);
467 	if (parsebuf) {
468 		parseindex--;
469 		if (parseindex >= 0)
470 			return (c);
471 	}
472 	if (pushback_index < MAXPUSHBACK-1)
473 		return (pushback_buffer[pushback_index++] = c);
474 	else
475 		return (EOF);
476 }
477 
478 int
479 findeol(void)
480 {
481 	int c;
482 
483 	parsebuf = NULL;
484 
485 	/* Skip to either EOF or the first real EOL. */
486 	while (1) {
487 		if (pushback_index)
488 			c = pushback_buffer[--pushback_index];
489 		else
490 			c = lgetc(0);
491 		if (c == '\n') {
492 			file->lineno++;
493 			break;
494 		}
495 		if (c == EOF)
496 			break;
497 	}
498 	return (ERROR);
499 }
500 
501 int
502 yylex(void)
503 {
504 	unsigned char buf[8096];
505 	unsigned char *p, *val;
506 	int quotec, next, c;
507 	int token;
508 
509 top:
510 	p = buf;
511 	c = lgetc(0);
512 	while (c == ' ' || c == '\t')
513 		c = lgetc(0); /* nothing */
514 
515 	yylval.lineno = file->lineno;
516 	if (c == '#') {
517 		c = lgetc(0);
518 		while (c != '\n' && c != EOF)
519 			c = lgetc(0); /* nothing */
520 	}
521 	if (c == '$' && parsebuf == NULL) {
522 		while (1) {
523 			c = lgetc(0);
524 			if (c == EOF)
525 				return (0);
526 
527 			if (p + 1 >= buf + sizeof(buf) - 1) {
528 				yyerror("string too long");
529 				return (findeol());
530 			}
531 			if (isalnum(c) || c == '_') {
532 				*p++ = c;
533 				continue;
534 			}
535 			*p = '\0';
536 			lungetc(c);
537 			break;
538 		}
539 		val = symget(buf);
540 		if (val == NULL) {
541 			yyerror("macro '%s' not defined", buf);
542 			return (findeol());
543 		}
544 		parsebuf = val;
545 		parseindex = 0;
546 		goto top;
547 	}
548 
549 	switch (c) {
550 	case '\'':
551 	case '"':
552 		quotec = c;
553 		while (1) {
554 			c = lgetc(quotec);
555 			if (c == EOF)
556 				return (0);
557 			if (c == '\n') {
558 				file->lineno++;
559 				continue;
560 			} else if (c == '\\') {
561 				next = lgetc(quotec);
562 				if (next == EOF)
563 					return (0);
564 				if (next == quotec || c == ' ' || c == '\t')
565 					c = next;
566 				else if (next == '\n') {
567 					file->lineno++;
568 					continue;
569 				} else
570 					lungetc(next);
571 			} else if (c == quotec) {
572 				*p = '\0';
573 				break;
574 			} else if (c == '\0') {
575 				yyerror("syntax error");
576 				return (findeol());
577 			}
578 			if (p + 1 >= buf + sizeof(buf) - 1) {
579 				yyerror("string too long");
580 				return (findeol());
581 			}
582 			*p++ = c;
583 		}
584 		yylval.v.string = strdup(buf);
585 		if (yylval.v.string == NULL)
586 			err(1, "yylex: strdup");
587 		return (STRING);
588 	}
589 
590 #define allowed_to_end_number(x) \
591 	(isspace(x) || x == ')' || x ==',' || x == '/' || x == '}' || x == '=')
592 
593 	if (c == '-' || isdigit(c)) {
594 		do {
595 			*p++ = c;
596 			if ((unsigned)(p-buf) >= sizeof(buf)) {
597 				yyerror("string too long");
598 				return (findeol());
599 			}
600 			c = lgetc(0);
601 		} while (c != EOF && isdigit(c));
602 		lungetc(c);
603 		if (p == buf + 1 && buf[0] == '-')
604 			goto nodigits;
605 		if (c == EOF || allowed_to_end_number(c)) {
606 			const char *errstr = NULL;
607 
608 			*p = '\0';
609 			yylval.v.number = strtonum(buf, LLONG_MIN,
610 			    LLONG_MAX, &errstr);
611 			if (errstr) {
612 				yyerror("\"%s\" invalid number: %s",
613 				    buf, errstr);
614 				return (findeol());
615 			}
616 			return (NUMBER);
617 		} else {
618 nodigits:
619 			while (p > buf + 1)
620 				lungetc(*--p);
621 			c = *--p;
622 			if (c == '-')
623 				return (c);
624 		}
625 	}
626 
627 #define allowed_in_string(x) \
628 	(isalnum(x) || (ispunct(x) && x != '(' && x != ')' && \
629 	x != '{' && x != '}' && \
630 	x != '!' && x != '=' && x != '#' && \
631 	x != ','))
632 
633 	if (isalnum(c) || c == ':' || c == '_') {
634 		do {
635 			*p++ = c;
636 			if ((unsigned)(p-buf) >= sizeof(buf)) {
637 				yyerror("string too long");
638 				return (findeol());
639 			}
640 			c = lgetc(0);
641 		} while (c != EOF && (allowed_in_string(c)));
642 		lungetc(c);
643 		*p = '\0';
644 		token = lookup(buf);
645 		if (token == STRING) {
646 			yylval.v.string = strdup(buf);
647 			if (yylval.v.string == NULL)
648 				err(1, "yylex: strdup");
649 		}
650 		return (token);
651 	}
652 	if (c == '\n') {
653 		yylval.lineno = file->lineno;
654 		file->lineno++;
655 	}
656 	if (c == EOF)
657 		return (0);
658 	return (c);
659 }
660 
661 int
662 check_file_secrecy(int fd, const char *fname)
663 {
664 	struct stat st;
665 
666 	if (fstat(fd, &st)) {
667 		log_warn("cannot stat %s", fname);
668 		return (-1);
669 	}
670 	if (st.st_uid != 0 && st.st_uid != getuid()) {
671 		log_warnx("%s: owner not root or current user", fname);
672 		return (-1);
673 	}
674 	if (st.st_mode & (S_IWGRP | S_IXGRP | S_IRWXO)) {
675 		log_warnx("%s: group writable or world read/writable", fname);
676 		return (-1);
677 	}
678 	return (0);
679 }
680 
681 struct file *
682 newfile(const char *name, int secret, int required)
683 {
684 	struct file *nfile;
685 
686 	nfile = calloc(1, sizeof(struct file));
687 	if (nfile == NULL) {
688 		log_warn("calloc");
689 		return (NULL);
690 	}
691 	nfile->name = strdup(name);
692 	if (nfile->name == NULL) {
693 		log_warn("strdup");
694 		free(nfile);
695 		return (NULL);
696 	}
697 	nfile->stream = fopen(nfile->name, "r");
698 	if (nfile->stream == NULL) {
699 		if (required)
700 			log_warn("open %s", nfile->name);
701 		free(nfile->name);
702 		free(nfile);
703 		return (NULL);
704 	} else if (secret &&
705 	    check_file_secrecy(fileno(nfile->stream), nfile->name)) {
706 		fclose(nfile->stream);
707 		free(nfile->name);
708 		free(nfile);
709 		return (NULL);
710 	}
711 	nfile->lineno = 1;
712 	return (nfile);
713 }
714 
715 static void
716 closefile(struct file *xfile)
717 {
718 	fclose(xfile->stream);
719 	free(xfile->name);
720 	free(xfile);
721 }
722 
723 int
724 parse_config(const char *filename, enum gotd_procid proc_id,
725     struct gotd *env, int require_config_file)
726 {
727 	struct sym *sym, *next;
728 	struct gotd_repo *repo;
729 
730 	memset(env, 0, sizeof(*env));
731 
732 	gotd = env;
733 	gotd_proc_id = proc_id;
734 	TAILQ_INIT(&gotd->repos);
735 
736 	/* Apply default values. */
737 	if (strlcpy(gotd->unix_socket_path, GOTD_UNIX_SOCKET,
738 	    sizeof(gotd->unix_socket_path)) >= sizeof(gotd->unix_socket_path)) {
739 		fprintf(stderr, "%s: unix socket path too long", __func__);
740 		return -1;
741 	}
742 	if (strlcpy(gotd->user_name, GOTD_USER,
743 	    sizeof(gotd->user_name)) >= sizeof(gotd->user_name)) {
744 		fprintf(stderr, "%s: user name too long", __func__);
745 		return -1;
746 	}
747 
748 	gotd->request_timeout.tv_sec = GOTD_DEFAULT_REQUEST_TIMEOUT;
749 	gotd->request_timeout.tv_usec = 0;
750 
751 	file = newfile(filename, 0, require_config_file);
752 	if (file == NULL)
753 		return require_config_file ? -1 : 0;
754 
755 	yyparse();
756 	errors = file->errors;
757 	closefile(file);
758 
759 	/* Free macros and check which have not been used. */
760 	TAILQ_FOREACH_SAFE(sym, &symhead, entry, next) {
761 		if ((gotd->verbosity > 1) && !sym->used)
762 			fprintf(stderr, "warning: macro '%s' not used\n",
763 			    sym->nam);
764 		if (!sym->persist) {
765 			free(sym->nam);
766 			free(sym->val);
767 			TAILQ_REMOVE(&symhead, sym, entry);
768 			free(sym);
769 		}
770 	}
771 
772 	if (errors)
773 		return (-1);
774 
775 	TAILQ_FOREACH(repo, &gotd->repos, entry) {
776 		if (repo->path[0] == '\0') {
777 			log_warnx("repository \"%s\": no path provided in "
778 			    "configuration file", repo->name);
779 			return (-1);
780 		}
781 	}
782 
783 	if (proc_id == PROC_GOTD && TAILQ_EMPTY(&gotd->repos)) {
784 		log_warnx("no repository defined in configuration file");
785 		return (-1);
786 	}
787 
788 	return (0);
789 }
790 
791 static int
792 uid_connection_limit_cmp(const void *pa, const void *pb)
793 {
794 	const struct gotd_uid_connection_limit *a = pa, *b = pb;
795 
796 	if (a->uid < b->uid)
797 		return -1;
798 	else if (a->uid > b->uid);
799 		return 1;
800 
801 	return 0;
802 }
803 
804 static int
805 conf_limit_user_connections(const char *user, int maximum)
806 {
807 	uid_t uid;
808 	struct gotd_uid_connection_limit *limit;
809 	size_t nlimits;
810 
811 	if (maximum < 1) {
812 		yyerror("max connections cannot be smaller 1");
813 		return -1;
814 	}
815 	if (maximum > GOTD_MAXCLIENTS) {
816 		yyerror("max connections must be <= %d", GOTD_MAXCLIENTS);
817 		return -1;
818 	}
819 
820 	if (gotd_auth_parseuid(user, &uid) == -1) {
821 		yyerror("%s: no such user", user);
822 		return -1;
823 	}
824 
825 	limit = gotd_find_uid_connection_limit(gotd->connection_limits,
826 	    gotd->nconnection_limits, uid);
827 	if (limit) {
828 		limit->max_connections = maximum;
829 		return 0;
830 	}
831 
832 	limit = gotd->connection_limits;
833 	nlimits = gotd->nconnection_limits + 1;
834 	limit = reallocarray(limit, nlimits, sizeof(*limit));
835 	if (limit == NULL)
836 		fatal("reallocarray");
837 
838 	limit[nlimits - 1].uid = uid;
839 	limit[nlimits - 1].max_connections = maximum;
840 
841 	gotd->connection_limits = limit;
842 	gotd->nconnection_limits = nlimits;
843 	qsort(gotd->connection_limits, gotd->nconnection_limits,
844 	    sizeof(gotd->connection_limits[0]), uid_connection_limit_cmp);
845 
846 	return 0;
847 }
848 
849 static struct gotd_repo *
850 conf_new_repo(const char *name)
851 {
852 	struct gotd_repo *repo;
853 
854 	if (name[0] == '\0') {
855 		fatalx("syntax error: empty repository name found in %s",
856 		    file->name);
857 	}
858 
859 	if (strchr(name, '\n') != NULL)
860 		fatalx("repository names must not contain linefeeds: %s", name);
861 
862 	repo = calloc(1, sizeof(*repo));
863 	if (repo == NULL)
864 		fatalx("%s: calloc", __func__);
865 
866 	STAILQ_INIT(&repo->rules);
867 	TAILQ_INIT(&repo->protected_tag_namespaces);
868 	TAILQ_INIT(&repo->protected_branch_namespaces);
869 	TAILQ_INIT(&repo->protected_branches);
870 
871 	if (strlcpy(repo->name, name, sizeof(repo->name)) >=
872 	    sizeof(repo->name))
873 		fatalx("%s: strlcpy", __func__);
874 
875 	TAILQ_INSERT_TAIL(&gotd->repos, repo, entry);
876 	gotd->nrepos++;
877 
878 	return repo;
879 };
880 
881 static void
882 conf_new_access_rule(struct gotd_repo *repo, enum gotd_access access,
883     int authorization, char *identifier)
884 {
885 	struct gotd_access_rule *rule;
886 
887 	rule = calloc(1, sizeof(*rule));
888 	if (rule == NULL)
889 		fatal("calloc");
890 
891 	rule->access = access;
892 	rule->authorization = authorization;
893 	rule->identifier = identifier;
894 
895 	STAILQ_INSERT_TAIL(&repo->rules, rule, entry);
896 }
897 
898 static int
899 refname_is_valid(char *refname)
900 {
901 	if (strlen(refname) < 5 || strncmp(refname, "refs/", 5) != 0) {
902 		yyerror("reference name must begin with \"refs/\": %s",
903 		    refname);
904 		return 0;
905 	}
906 
907 	if (!got_ref_name_is_valid(refname)) {
908 		yyerror("invalid reference name: %s", refname);
909 		return 0;
910 	}
911 
912 	return 1;
913 }
914 
915 static int
916 conf_protect_ref_namespace(struct got_pathlist_head *refs, char *namespace)
917 {
918 	const struct got_error *error;
919 	struct got_pathlist_entry *new;
920 	char *s;
921 
922 	got_path_strip_trailing_slashes(namespace);
923 	if (!refname_is_valid(namespace))
924 		return -1;
925 	if (asprintf(&s, "%s/", namespace) == -1) {
926 		yyerror("asprintf: %s", strerror(errno));
927 		return -1;
928 	}
929 
930 	error = got_pathlist_insert(&new, refs, s, NULL);
931 	if (error || new == NULL) {
932 		free(s);
933 		if (error)
934 			yyerror("got_pathlist_insert: %s", error->msg);
935 		else
936 			yyerror("duplicate protect namespace %s", namespace);
937 		return -1;
938 	}
939 
940 	return 0;
941 }
942 
943 static int
944 conf_protect_tag_namespace(struct gotd_repo *repo, char *namespace)
945 {
946 	return conf_protect_ref_namespace(&repo->protected_tag_namespaces,
947 	    namespace);
948 }
949 
950 static int
951 conf_protect_branch_namespace(struct gotd_repo *repo, char *namespace)
952 {
953 	return conf_protect_ref_namespace(&repo->protected_branch_namespaces,
954 	    namespace);
955 }
956 
957 static int
958 conf_protect_branch(struct gotd_repo *repo, char *branchname)
959 {
960 	const struct got_error *error;
961 	struct got_pathlist_entry *new;
962 	char *refname;
963 
964 	if (strncmp(branchname, "refs/heads/", 11) != 0) {
965 		if (asprintf(&refname, "refs/heads/%s", branchname) == -1) {
966 			yyerror("asprintf: %s", strerror(errno));
967 			return -1;
968 		}
969 	} else {
970 		refname = strdup(branchname);
971 		if (refname == NULL) {
972 			yyerror("strdup: %s", strerror(errno));
973 			return -1;
974 		}
975 	}
976 
977 	if (!refname_is_valid(refname)) {
978 		free(refname);
979 		return -1;
980 	}
981 
982 	error = got_pathlist_insert(&new, &repo->protected_branches,
983 	    refname, NULL);
984 	if (error || new == NULL) {
985 		free(refname);
986 		if (error)
987 			yyerror("got_pathlist_insert: %s", error->msg);
988 		else
989 			yyerror("duplicate protect branch %s", branchname);
990 		return -1;
991 	}
992 
993 	return 0;
994 }
995 
996 int
997 symset(const char *nam, const char *val, int persist)
998 {
999 	struct sym *sym;
1000 
1001 	TAILQ_FOREACH(sym, &symhead, entry) {
1002 		if (strcmp(nam, sym->nam) == 0)
1003 			break;
1004 	}
1005 
1006 	if (sym != NULL) {
1007 		if (sym->persist == 1)
1008 			return (0);
1009 		else {
1010 			free(sym->nam);
1011 			free(sym->val);
1012 			TAILQ_REMOVE(&symhead, sym, entry);
1013 			free(sym);
1014 		}
1015 	}
1016 	sym = calloc(1, sizeof(*sym));
1017 	if (sym == NULL)
1018 		return (-1);
1019 
1020 	sym->nam = strdup(nam);
1021 	if (sym->nam == NULL) {
1022 		free(sym);
1023 		return (-1);
1024 	}
1025 	sym->val = strdup(val);
1026 	if (sym->val == NULL) {
1027 		free(sym->nam);
1028 		free(sym);
1029 		return (-1);
1030 	}
1031 	sym->used = 0;
1032 	sym->persist = persist;
1033 	TAILQ_INSERT_TAIL(&symhead, sym, entry);
1034 	return (0);
1035 }
1036 
1037 char *
1038 symget(const char *nam)
1039 {
1040 	struct sym *sym;
1041 
1042 	TAILQ_FOREACH(sym, &symhead, entry) {
1043 		if (strcmp(nam, sym->nam) == 0) {
1044 			sym->used = 1;
1045 			return (sym->val);
1046 		}
1047 	}
1048 	return (NULL);
1049 }
1050 
1051 struct gotd_repo *
1052 gotd_find_repo_by_name(const char *repo_name, struct gotd *gotd)
1053 {
1054 	struct gotd_repo *repo;
1055 	size_t namelen;
1056 
1057 	TAILQ_FOREACH(repo, &gotd->repos, entry) {
1058 		namelen = strlen(repo->name);
1059 		if (strncmp(repo->name, repo_name, namelen) != 0)
1060 			continue;
1061 		if (repo_name[namelen] == '\0' ||
1062 		    strcmp(&repo_name[namelen], ".git") == 0)
1063 			return repo;
1064 	}
1065 
1066 	return NULL;
1067 }
1068 
1069 struct gotd_repo *
1070 gotd_find_repo_by_path(const char *repo_path, struct gotd *gotd)
1071 {
1072 	struct gotd_repo *repo;
1073 
1074 	TAILQ_FOREACH(repo, &gotd->repos, entry) {
1075 		if (strcmp(repo->path, repo_path) == 0)
1076 			return repo;
1077 	}
1078 
1079 	return NULL;
1080 }