1 /*
2  * Copyright (c) 2020 Tracey Emery <tracey@openbsd.org>
3  * Copyright (c) 2004, 2005 Esben Norby <norby@openbsd.org>
4  * Copyright (c) 2004 Ryan McBride <mcbride@openbsd.org>
5  * Copyright (c) 2002, 2003, 2004 Henning Brauer <henning@openbsd.org>
6  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
7  * Copyright (c) 2001 Daniel Hartmeier.  All rights reserved.
8  * Copyright (c) 2001 Theo de Raadt.  All rights reserved.
9  *
10  * Permission to use, copy, modify, and distribute this software for any
11  * purpose with or without fee is hereby granted, provided that the above
12  * copyright notice and this permission notice appear in all copies.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
15  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
16  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
17  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
18  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
19  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
20  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
21  */
22 
23 %{
24 #include <sys/types.h>
25 #include <sys/queue.h>
26 #include <sys/socket.h>
27 #include <sys/stat.h>
28 
29 #include <netinet/in.h>
30 
31 #include <arpa/inet.h>
32 
33 #include <ctype.h>
34 #include <err.h>
35 #include <errno.h>
36 #include <event.h>
37 #include <ifaddrs.h>
38 #include <imsg.h>
39 #include <limits.h>
40 #include <stdarg.h>
41 #include <stdio.h>
42 #include <string.h>
43 #include <syslog.h>
44 #include <unistd.h>
45 
46 #include "got_error.h"
47 #include "got.h"
48 
49 TAILQ_HEAD(files, file)		 files = TAILQ_HEAD_INITIALIZER(files);
50 static struct file {
51 	TAILQ_ENTRY(file)	 entry;
52 	FILE			*stream;
53 	char			*name;
54 	size_t	 		 ungetpos;
55 	size_t			 ungetsize;
56 	u_char			*ungetbuf;
57 	int			 eof_reached;
58 	int			 lineno;
59 } *file, *topfile;
60 static const struct got_error*	pushfile(struct file**, const char *);
61 int		 popfile(void);
62 int		 yyparse(void);
63 int		 yylex(void);
64 int		 yyerror(const char *, ...)
65     __attribute__((__format__ (printf, 1, 2)))
66     __attribute__((__nonnull__ (1)));
67 int		 kw_cmp(const void *, const void *);
68 int		 lookup(char *);
69 int		 igetc(void);
70 int		 lgetc(int);
71 void		 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 const struct got_error* gerror = NULL;
87 struct gotconfig_remote_repo *remote;
88 struct gotconfig gotconfig;
89 static const struct got_error* new_remote(struct gotconfig_remote_repo **);
90 
91 typedef struct {
92 	union {
93 		int64_t		 number;
94 		char		*string;
95 	} v;
96 	int lineno;
97 } YYSTYPE;
98 
99 %}
100 
101 %token	ERROR
102 %token	REMOTE REPOSITORY SERVER PROTOCOL USER
103 %token	<v.string>	STRING
104 %token	<v.number>	NUMBER
105 
106 %%
107 
108 grammar		: /* empty */
109 		| grammar '\n'
110 		| grammar remote '\n'
111 		;
112 remoteopts2	: remoteopts2 remoteopts1 nl
113 	    	| remoteopts1 optnl
114 		;
115 remoteopts1	: REPOSITORY STRING {
116 	    		remote->repository = strdup($2);
117 			if (remote->repository == NULL) {
118 				free($2);
119 				yyerror("strdup");
120 				YYERROR;
121 			}
122 			free($2);
123 	    	}
124 	    	| SERVER STRING {
125 	    		remote->server = strdup($2);
126 			if (remote->server == NULL) {
127 				free($2);
128 				yyerror("strdup");
129 				YYERROR;
130 			}
131 			free($2);
132 		}
133 		| PROTOCOL STRING {
134 	    		remote->protocol = strdup($2);
135 			if (remote->protocol == NULL) {
136 				free($2);
137 				yyerror("strdup");
138 				YYERROR;
139 			}
140 			free($2);
141 		}
142 		| USER STRING {
143 	    		remote->user = strdup($2);
144 			if (remote->user == NULL) {
145 				free($2);
146 				yyerror("strdup");
147 				YYERROR;
148 			}
149 			free($2);
150 		}
151 	    	;
152 remote		: REMOTE STRING {
153 			static const struct got_error* error;
154 
155 			error = new_remote(&remote);
156 			if (error) {
157 				free($2);
158 				yyerror("%s", error->msg);
159 				YYERROR;
160 			}
161 			remote->name = strdup($2);
162 			if (remote->name == NULL) {
163 				free($2);
164 				yyerror("strdup");
165 				YYERROR;
166 			}
167 			free($2);
168 		} '{' optnl remoteopts2 '}' {
169 			TAILQ_INSERT_TAIL(&gotconfig.remotes, remote, entry);
170 			gotconfig.nremotes++;
171 		}
172 		;
173 optnl		: '\n' optnl
174 		| /* empty */
175 		;
176 nl		: '\n' optnl
177 		;
178 %%
179 
180 struct keywords {
181 	const char	*k_name;
182 	int		 k_val;
183 };
184 
185 int
186 yyerror(const char *fmt, ...)
187 {
188 	va_list		 ap;
189 	char		*msg;
190 	char		*err = NULL;
191 
192 	va_start(ap, fmt);
193 	if (vasprintf(&msg, fmt, ap) == -1) {
194 		gerror =  got_error_from_errno("vasprintf");
195 		return 0;
196 	}
197 	va_end(ap);
198 	if (asprintf(&err, "%s:%d: %s", file->name, yylval.lineno, msg) == -1) {
199 		gerror = got_error_from_errno("asprintf");
200 		return(0);
201 	}
202 	gerror = got_error_msg(GOT_ERR_PARSE_Y_YY, strdup(err));
203 	free(msg);
204 	free(err);
205 	return(0);
206 }
207 
208 int
209 kw_cmp(const void *k, const void *e)
210 {
211 	return (strcmp(k, ((const struct keywords *)e)->k_name));
212 }
213 
214 int
215 lookup(char *s)
216 {
217 	/* This has to be sorted always. */
218 	static const struct keywords keywords[] = {
219 		{"protocol",		PROTOCOL},
220 		{"remote",		REMOTE},
221 		{"repository",		REPOSITORY},
222 		{"server",		SERVER},
223 		{"user",		USER},
224 	};
225 	const struct keywords	*p;
226 
227 	p = bsearch(s, keywords, sizeof(keywords)/sizeof(keywords[0]),
228 	    sizeof(keywords[0]), kw_cmp);
229 
230 	if (p)
231 		return (p->k_val);
232 	else
233 		return (STRING);
234 }
235 
236 #define START_EXPAND	1
237 #define DONE_EXPAND	2
238 
239 static int	expanding;
240 
241 int
242 igetc(void)
243 {
244 	int	c;
245 
246 	while (1) {
247 		if (file->ungetpos > 0)
248 			c = file->ungetbuf[--file->ungetpos];
249 		else
250 			c = getc(file->stream);
251 
252 		if (c == START_EXPAND)
253 			expanding = 1;
254 		else if (c == DONE_EXPAND)
255 			expanding = 0;
256 		else
257 			break;
258 	}
259 	return (c);
260 }
261 
262 int
263 lgetc(int quotec)
264 {
265 	int		c, next;
266 
267 	if (quotec) {
268 		if ((c = igetc()) == EOF) {
269 			yyerror("reached end of file while parsing "
270 			    "quoted string");
271 			if (file == topfile || popfile() == EOF)
272 				return (EOF);
273 			return (quotec);
274 		}
275 		return (c);
276 	}
277 
278 	while ((c = igetc()) == '\\') {
279 		next = igetc();
280 		if (next != '\n') {
281 			c = next;
282 			break;
283 		}
284 		yylval.lineno = file->lineno;
285 		file->lineno++;
286 	}
287 
288 	if (c == EOF) {
289 		/*
290 		 * Fake EOL when hit EOF for the first time. This gets line
291 		 * count right if last line in included file is syntactically
292 		 * invalid and has no newline.
293 		 */
294 		if (file->eof_reached == 0) {
295 			file->eof_reached = 1;
296 			return ('\n');
297 		}
298 		while (c == EOF) {
299 			if (file == topfile || popfile() == EOF)
300 				return (EOF);
301 			c = igetc();
302 		}
303 	}
304 	return (c);
305 }
306 
307 void
308 lungetc(int c)
309 {
310 	if (c == EOF)
311 		return;
312 
313 	if (file->ungetpos >= file->ungetsize) {
314 		void *p = reallocarray(file->ungetbuf, file->ungetsize, 2);
315 		if (p == NULL)
316 			err(1, "%s", __func__);
317 		file->ungetbuf = p;
318 		file->ungetsize *= 2;
319 	}
320 	file->ungetbuf[file->ungetpos++] = c;
321 }
322 
323 int
324 findeol(void)
325 {
326 	int	c;
327 
328 	/* Skip to either EOF or the first real EOL. */
329 	while (1) {
330 		c = lgetc(0);
331 		if (c == '\n') {
332 			file->lineno++;
333 			break;
334 		}
335 		if (c == EOF)
336 			break;
337 	}
338 	return (ERROR);
339 }
340 
341 int
342 yylex(void)
343 {
344 	unsigned char	 buf[8096];
345 	unsigned char	*p, *val;
346 	int		 quotec, next, c;
347 	int		 token;
348 
349 top:
350 	p = buf;
351 	while ((c = lgetc(0)) == ' ' || c == '\t')
352 		; /* nothing */
353 
354 	yylval.lineno = file->lineno;
355 	if (c == '#')
356 		while ((c = lgetc(0)) != '\n' && c != EOF)
357 			; /* nothing */
358 	if (c == '$' && !expanding) {
359 		while (1) {
360 			if ((c = lgetc(0)) == EOF)
361 				return (0);
362 
363 			if (p + 1 >= buf + sizeof(buf) - 1) {
364 				yyerror("string too long");
365 				return (findeol());
366 			}
367 			if (isalnum(c) || c == '_') {
368 				*p++ = c;
369 				continue;
370 			}
371 			*p = '\0';
372 			lungetc(c);
373 			break;
374 		}
375 		val = symget(buf);
376 		if (val == NULL) {
377 			yyerror("macro '%s' not defined", buf);
378 			return (findeol());
379 		}
380 		p = val + strlen(val) - 1;
381 		lungetc(DONE_EXPAND);
382 		while (p >= val) {
383 			lungetc(*p);
384 			p--;
385 		}
386 		lungetc(START_EXPAND);
387 		goto top;
388 	}
389 
390 	switch (c) {
391 	case '\'':
392 	case '"':
393 		quotec = c;
394 		while (1) {
395 			if ((c = lgetc(quotec)) == EOF)
396 				return (0);
397 			if (c == '\n') {
398 				file->lineno++;
399 				continue;
400 			} else if (c == '\\') {
401 				if ((next = lgetc(quotec)) == EOF)
402 					return (0);
403 				if (next == quotec || c == ' ' || c == '\t')
404 					c = next;
405 				else if (next == '\n') {
406 					file->lineno++;
407 					continue;
408 				} else
409 					lungetc(next);
410 			} else if (c == quotec) {
411 				*p = '\0';
412 				break;
413 			} else if (c == '\0') {
414 				yyerror("syntax error");
415 				return (findeol());
416 			}
417 			if (p + 1 >= buf + sizeof(buf) - 1) {
418 				yyerror("string too long");
419 				return (findeol());
420 			}
421 			*p++ = c;
422 		}
423 		yylval.v.string = strdup(buf);
424 		if (yylval.v.string == NULL)
425 			err(1, "%s", __func__);
426 		return (STRING);
427 	}
428 
429 #define allowed_to_end_number(x) \
430 	(isspace(x) || x == ')' || x ==',' || x == '/' || x == '}' || x == '=')
431 
432 	if (c == '-' || isdigit(c)) {
433 		do {
434 			*p++ = c;
435 			if ((unsigned)(p-buf) >= sizeof(buf)) {
436 				yyerror("string too long");
437 				return (findeol());
438 			}
439 		} while ((c = lgetc(0)) != EOF && isdigit(c));
440 		lungetc(c);
441 		if (p == buf + 1 && buf[0] == '-')
442 			goto nodigits;
443 		if (c == EOF || allowed_to_end_number(c)) {
444 			const char *errstr = NULL;
445 
446 			*p = '\0';
447 			yylval.v.number = strtonum(buf, LLONG_MIN,
448 			    LLONG_MAX, &errstr);
449 			if (errstr) {
450 				yyerror("\"%s\" invalid number: %s",
451 				    buf, errstr);
452 				return (findeol());
453 			}
454 			return (NUMBER);
455 		} else {
456 nodigits:
457 			while (p > buf + 1)
458 				lungetc(*--p);
459 			c = *--p;
460 			if (c == '-')
461 				return (c);
462 		}
463 	}
464 
465 #define allowed_in_string(x) \
466 	(isalnum(x) || (ispunct(x) && x != '(' && x != ')' && \
467 	x != '{' && x != '}' && \
468 	x != '!' && x != '=' && x != '#' && \
469 	x != ','))
470 
471 	if (isalnum(c) || c == ':' || c == '_') {
472 		do {
473 			*p++ = c;
474 			if ((unsigned)(p-buf) >= sizeof(buf)) {
475 				yyerror("string too long");
476 				return (findeol());
477 			}
478 		} while ((c = lgetc(0)) != EOF && (allowed_in_string(c)));
479 		lungetc(c);
480 		*p = '\0';
481 		if ((token = lookup(buf)) == STRING)
482 			if ((yylval.v.string = strdup(buf)) == NULL)
483 				err(1, "%s", __func__);
484 		return (token);
485 	}
486 	if (c == '\n') {
487 		yylval.lineno = file->lineno;
488 		file->lineno++;
489 	}
490 	if (c == EOF)
491 		return (0);
492 	return (c);
493 }
494 
495 static const struct got_error*
496 pushfile(struct file **nfile, const char *name)
497 {
498 	const struct got_error* error = NULL;
499 
500 	if (((*nfile) = calloc(1, sizeof(struct file))) == NULL)
501 		return got_error_from_errno2(__func__, "calloc");
502 	if (((*nfile)->name = strdup(name)) == NULL) {
503 		free(nfile);
504 		return got_error_from_errno2(__func__, "strdup");
505 	}
506 	if (((*nfile)->stream = fopen((*nfile)->name, "r")) == NULL) {
507 		char *msg = NULL;
508 		if (asprintf(&msg, "%s", (*nfile)->name) == -1)
509 			return got_error_from_errno("asprintf");
510 		error = got_error_msg(GOT_ERR_NO_CONFIG_FILE, msg);
511 		free((*nfile)->name);
512 		free((*nfile));
513 		free(msg);
514 		return error;
515 	}
516 	(*nfile)->lineno = TAILQ_EMPTY(&files) ? 1 : 0;
517 	(*nfile)->ungetsize = 16;
518 	(*nfile)->ungetbuf = malloc((*nfile)->ungetsize);
519 	if ((*nfile)->ungetbuf == NULL) {
520 		fclose((*nfile)->stream);
521 		free((*nfile)->name);
522 		free((*nfile));
523 		return got_error_from_errno2(__func__, "malloc");
524 	}
525 	TAILQ_INSERT_TAIL(&files, (*nfile), entry);
526 	return error;
527 }
528 
529 static const struct got_error*
530 new_remote(struct gotconfig_remote_repo **remote)
531 {
532 	const struct got_error *error = NULL;
533 
534 	*remote = calloc(1, sizeof(**remote));
535 	if (*remote == NULL)
536 	    error = got_error_from_errno("calloc");
537 	return error;
538 }
539 
540 int
541 popfile(void)
542 {
543 	struct file	*prev = NULL;
544 
545 	TAILQ_REMOVE(&files, file, entry);
546 	fclose(file->stream);
547 	free(file->name);
548 	free(file->ungetbuf);
549 	free(file);
550 	file = prev;
551 	return (file ? 0 : EOF);
552 }
553 
554 const struct got_error*
555 gotconfig_parse(struct gotconfig **conf, const char *filename)
556 {
557 	struct sym	*sym, *next;
558 
559 	*conf = NULL;
560 
561 	/*
562 	 * We don't require that gotconfig exists
563 	 * So, null gerror and goto done
564 	 */
565 	gerror = pushfile(&file, filename);
566 	if (gerror && gerror->code == GOT_ERR_NO_CONFIG_FILE) {
567 		gerror = NULL;
568 		goto done;
569 	} else if (gerror)
570 		return gerror;
571 
572 	TAILQ_INIT(&gotconfig.remotes);
573 	topfile = file;
574 
575 	yyparse();
576 	popfile();
577 
578 	/* Free macros and check which have not been used. */
579 	TAILQ_FOREACH_SAFE(sym, &symhead, entry, next) {
580 		if (!sym->persist) {
581 			free(sym->nam);
582 			free(sym->val);
583 			TAILQ_REMOVE(&symhead, sym, entry);
584 			free(sym);
585 		}
586 	}
587 done:
588 	*conf = &gotconfig;
589 	return gerror;
590 }
591 
592 void
593 gotconfig_free(struct gotconfig *conf)
594 {
595 	struct gotconfig_remote_repo *remote;
596 
597 	while (!TAILQ_EMPTY(&conf->remotes)) {
598 		remote = TAILQ_FIRST(&conf->remotes);
599 		TAILQ_REMOVE(&conf->remotes, remote, entry);
600 		free(remote->name);
601 		free(remote->repository);
602 		free(remote->server);
603 		free(remote->protocol);
604 		free(remote->user);
605 		free(remote);
606 	}
607 }
608 
609 int
610 symset(const char *nam, const char *val, int persist)
611 {
612 	struct sym	*sym;
613 
614 	TAILQ_FOREACH(sym, &symhead, entry) {
615 		if (strcmp(nam, sym->nam) == 0)
616 			break;
617 	}
618 
619 	if (sym != NULL) {
620 		if (sym->persist == 1)
621 			return (0);
622 		else {
623 			free(sym->nam);
624 			free(sym->val);
625 			TAILQ_REMOVE(&symhead, sym, entry);
626 			free(sym);
627 		}
628 	}
629 	if ((sym = calloc(1, sizeof(*sym))) == NULL)
630 		return (-1);
631 
632 	sym->nam = strdup(nam);
633 	if (sym->nam == NULL) {
634 		free(sym);
635 		return (-1);
636 	}
637 	sym->val = strdup(val);
638 	if (sym->val == NULL) {
639 		free(sym->nam);
640 		free(sym);
641 		return (-1);
642 	}
643 	sym->used = 0;
644 	sym->persist = persist;
645 	TAILQ_INSERT_TAIL(&symhead, sym, entry);
646 	return (0);
647 }
648 
649 int
650 cmdline_symset(char *s)
651 {
652 	char	*sym, *val;
653 	int	ret;
654 	size_t	len;
655 
656 	if ((val = strrchr(s, '=')) == NULL)
657 		return (-1);
658 
659 	len = strlen(s) - strlen(val) + 1;
660 	if ((sym = malloc(len)) == NULL)
661 		errx(1, "cmdline_symset: malloc");
662 
663 	strlcpy(sym, s, len);
664 
665 	ret = symset(sym, val + 1, 1);
666 	free(sym);
667 
668 	return (ret);
669 }
670 
671 char *
672 symget(const char *nam)
673 {
674 	struct sym	*sym;
675 
676 	TAILQ_FOREACH(sym, &symhead, entry) {
677 		if (strcmp(nam, sym->nam) == 0) {
678 			sym->used = 1;
679 			return (sym->val);
680 		}
681 	}
682 	return (NULL);
683 }