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 got_config_list_entry *gotconfig;
88 struct got_config_list got_config_list;
89 static const struct got_error*	new_remote(struct got_config_list_entry **);
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 	    		gotconfig->repository = strdup($2);
117 			if (gotconfig->repository == NULL) {
118 				free($2);
119 				yyerror("strdup");
120 				YYERROR;
121 			}
122 			free($2);
123 	    	}
124 	    	| SERVER STRING {
125 	    		gotconfig->server = strdup($2);
126 			if (gotconfig->server == NULL) {
127 				free($2);
128 				yyerror("strdup");
129 				YYERROR;
130 			}
131 			free($2);
132 		}
133 		| PROTOCOL STRING {
134 	    		gotconfig->protocol = strdup($2);
135 			if (gotconfig->protocol == NULL) {
136 				free($2);
137 				yyerror("strdup");
138 				YYERROR;
139 			}
140 			free($2);
141 		}
142 		| USER STRING {
143 	    		gotconfig->user = strdup($2);
144 			if (gotconfig->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(&gotconfig);
156 			if (error) {
157 				free($2);
158 				yyerror("%s", error->msg);
159 				YYERROR;
160 			}
161 			gotconfig->remote = strdup($2);
162 			if (gotconfig->remote == NULL) {
163 				free($2);
164 				yyerror("strdup");
165 				YYERROR;
166 			}
167 			free($2);
168 		} '{' optnl remoteopts2 '}' {
169 			TAILQ_INSERT_TAIL(&got_config_list, gotconfig, entry);
170 		}
171 		;
172 optnl		: '\n' optnl
173 		| /* empty */
174 		;
175 nl		: '\n' optnl
176 		;
177 %%
178 
179 struct keywords {
180 	const char	*k_name;
181 	int		 k_val;
182 };
183 
184 int
185 yyerror(const char *fmt, ...)
186 {
187 	va_list		 ap;
188 	char		*msg;
189 	char		*err = NULL;
190 
191 	va_start(ap, fmt);
192 	if (vasprintf(&msg, fmt, ap) == -1) {
193 		gerror =  got_error_from_errno("vasprintf");
194 		return 0;
195 	}
196 	va_end(ap);
197 	if (asprintf(&err, "%s:%d: %s", file->name, yylval.lineno, msg) == -1) {
198 		gerror = got_error_from_errno("asprintf");
199 		return(0);
200 	}
201 	gerror = got_error_msg(GOT_ERR_PARSE_Y_YY, strdup(err));
202 	free(msg);
203 	free(err);
204 	return(0);
205 }
206 
207 int
208 kw_cmp(const void *k, const void *e)
209 {
210 	return (strcmp(k, ((const struct keywords *)e)->k_name));
211 }
212 
213 int
214 lookup(char *s)
215 {
216 	/* This has to be sorted always. */
217 	static const struct keywords keywords[] = {
218 		{"protocol",		PROTOCOL},
219 		{"remote",		REMOTE},
220 		{"repository",		REPOSITORY},
221 		{"server",		SERVER},
222 		{"user",		USER},
223 	};
224 	const struct keywords	*p;
225 
226 	p = bsearch(s, keywords, sizeof(keywords)/sizeof(keywords[0]),
227 	    sizeof(keywords[0]), kw_cmp);
228 
229 	if (p)
230 		return (p->k_val);
231 	else
232 		return (STRING);
233 }
234 
235 #define START_EXPAND	1
236 #define DONE_EXPAND	2
237 
238 static int	expanding;
239 
240 int
241 igetc(void)
242 {
243 	int	c;
244 
245 	while (1) {
246 		if (file->ungetpos > 0)
247 			c = file->ungetbuf[--file->ungetpos];
248 		else
249 			c = getc(file->stream);
250 
251 		if (c == START_EXPAND)
252 			expanding = 1;
253 		else if (c == DONE_EXPAND)
254 			expanding = 0;
255 		else
256 			break;
257 	}
258 	return (c);
259 }
260 
261 int
262 lgetc(int quotec)
263 {
264 	int		c, next;
265 
266 	if (quotec) {
267 		if ((c = igetc()) == EOF) {
268 			yyerror("reached end of file while parsing "
269 			    "quoted string");
270 			if (file == topfile || popfile() == EOF)
271 				return (EOF);
272 			return (quotec);
273 		}
274 		return (c);
275 	}
276 
277 	while ((c = igetc()) == '\\') {
278 		next = igetc();
279 		if (next != '\n') {
280 			c = next;
281 			break;
282 		}
283 		yylval.lineno = file->lineno;
284 		file->lineno++;
285 	}
286 
287 	if (c == EOF) {
288 		/*
289 		 * Fake EOL when hit EOF for the first time. This gets line
290 		 * count right if last line in included file is syntactically
291 		 * invalid and has no newline.
292 		 */
293 		if (file->eof_reached == 0) {
294 			file->eof_reached = 1;
295 			return ('\n');
296 		}
297 		while (c == EOF) {
298 			if (file == topfile || popfile() == EOF)
299 				return (EOF);
300 			c = igetc();
301 		}
302 	}
303 	return (c);
304 }
305 
306 void
307 lungetc(int c)
308 {
309 	if (c == EOF)
310 		return;
311 
312 	if (file->ungetpos >= file->ungetsize) {
313 		void *p = reallocarray(file->ungetbuf, file->ungetsize, 2);
314 		if (p == NULL)
315 			err(1, "%s", __func__);
316 		file->ungetbuf = p;
317 		file->ungetsize *= 2;
318 	}
319 	file->ungetbuf[file->ungetpos++] = c;
320 }
321 
322 int
323 findeol(void)
324 {
325 	int	c;
326 
327 	/* Skip to either EOF or the first real EOL. */
328 	while (1) {
329 		c = lgetc(0);
330 		if (c == '\n') {
331 			file->lineno++;
332 			break;
333 		}
334 		if (c == EOF)
335 			break;
336 	}
337 	return (ERROR);
338 }
339 
340 int
341 yylex(void)
342 {
343 	unsigned char	 buf[8096];
344 	unsigned char	*p, *val;
345 	int		 quotec, next, c;
346 	int		 token;
347 
348 top:
349 	p = buf;
350 	while ((c = lgetc(0)) == ' ' || c == '\t')
351 		; /* nothing */
352 
353 	yylval.lineno = file->lineno;
354 	if (c == '#')
355 		while ((c = lgetc(0)) != '\n' && c != EOF)
356 			; /* nothing */
357 	if (c == '$' && !expanding) {
358 		while (1) {
359 			if ((c = lgetc(0)) == EOF)
360 				return (0);
361 
362 			if (p + 1 >= buf + sizeof(buf) - 1) {
363 				yyerror("string too long");
364 				return (findeol());
365 			}
366 			if (isalnum(c) || c == '_') {
367 				*p++ = c;
368 				continue;
369 			}
370 			*p = '\0';
371 			lungetc(c);
372 			break;
373 		}
374 		val = symget(buf);
375 		if (val == NULL) {
376 			yyerror("macro '%s' not defined", buf);
377 			return (findeol());
378 		}
379 		p = val + strlen(val) - 1;
380 		lungetc(DONE_EXPAND);
381 		while (p >= val) {
382 			lungetc(*p);
383 			p--;
384 		}
385 		lungetc(START_EXPAND);
386 		goto top;
387 	}
388 
389 	switch (c) {
390 	case '\'':
391 	case '"':
392 		quotec = c;
393 		while (1) {
394 			if ((c = lgetc(quotec)) == EOF)
395 				return (0);
396 			if (c == '\n') {
397 				file->lineno++;
398 				continue;
399 			} else if (c == '\\') {
400 				if ((next = lgetc(quotec)) == EOF)
401 					return (0);
402 				if (next == quotec || c == ' ' || c == '\t')
403 					c = next;
404 				else if (next == '\n') {
405 					file->lineno++;
406 					continue;
407 				} else
408 					lungetc(next);
409 			} else if (c == quotec) {
410 				*p = '\0';
411 				break;
412 			} else if (c == '\0') {
413 				yyerror("syntax error");
414 				return (findeol());
415 			}
416 			if (p + 1 >= buf + sizeof(buf) - 1) {
417 				yyerror("string too long");
418 				return (findeol());
419 			}
420 			*p++ = c;
421 		}
422 		yylval.v.string = strdup(buf);
423 		if (yylval.v.string == NULL)
424 			err(1, "%s", __func__);
425 		return (STRING);
426 	}
427 
428 #define allowed_to_end_number(x) \
429 	(isspace(x) || x == ')' || x ==',' || x == '/' || x == '}' || x == '=')
430 
431 	if (c == '-' || isdigit(c)) {
432 		do {
433 			*p++ = c;
434 			if ((unsigned)(p-buf) >= sizeof(buf)) {
435 				yyerror("string too long");
436 				return (findeol());
437 			}
438 		} while ((c = lgetc(0)) != EOF && isdigit(c));
439 		lungetc(c);
440 		if (p == buf + 1 && buf[0] == '-')
441 			goto nodigits;
442 		if (c == EOF || allowed_to_end_number(c)) {
443 			const char *errstr = NULL;
444 
445 			*p = '\0';
446 			yylval.v.number = strtonum(buf, LLONG_MIN,
447 			    LLONG_MAX, &errstr);
448 			if (errstr) {
449 				yyerror("\"%s\" invalid number: %s",
450 				    buf, errstr);
451 				return (findeol());
452 			}
453 			return (NUMBER);
454 		} else {
455 nodigits:
456 			while (p > buf + 1)
457 				lungetc(*--p);
458 			c = *--p;
459 			if (c == '-')
460 				return (c);
461 		}
462 	}
463 
464 #define allowed_in_string(x) \
465 	(isalnum(x) || (ispunct(x) && x != '(' && x != ')' && \
466 	x != '{' && x != '}' && \
467 	x != '!' && x != '=' && x != '#' && \
468 	x != ','))
469 
470 	if (isalnum(c) || c == ':' || c == '_') {
471 		do {
472 			*p++ = c;
473 			if ((unsigned)(p-buf) >= sizeof(buf)) {
474 				yyerror("string too long");
475 				return (findeol());
476 			}
477 		} while ((c = lgetc(0)) != EOF && (allowed_in_string(c)));
478 		lungetc(c);
479 		*p = '\0';
480 		if ((token = lookup(buf)) == STRING)
481 			if ((yylval.v.string = strdup(buf)) == NULL)
482 				err(1, "%s", __func__);
483 		return (token);
484 	}
485 	if (c == '\n') {
486 		yylval.lineno = file->lineno;
487 		file->lineno++;
488 	}
489 	if (c == EOF)
490 		return (0);
491 	return (c);
492 }
493 
494 static const struct got_error*
495 pushfile(struct file **nfile, const char *name)
496 {
497 	const struct got_error* error = NULL;
498 
499 	if (((*nfile) = calloc(1, sizeof(struct file))) == NULL)
500 		return got_error_from_errno2(__func__, "calloc");
501 	if (((*nfile)->name = strdup(name)) == NULL) {
502 		free(nfile);
503 		return got_error_from_errno2(__func__, "strdup");
504 	}
505 	if (((*nfile)->stream = fopen((*nfile)->name, "r")) == NULL) {
506 		char *msg = NULL;
507 		if (asprintf(&msg, "%s", (*nfile)->name) == -1)
508 			return got_error_from_errno("asprintf");
509 		error = got_error_msg(GOT_ERR_NO_CONFIG_FILE, msg);
510 		free((*nfile)->name);
511 		free((*nfile));
512 		free(msg);
513 		return error;
514 	}
515 	(*nfile)->lineno = TAILQ_EMPTY(&files) ? 1 : 0;
516 	(*nfile)->ungetsize = 16;
517 	(*nfile)->ungetbuf = malloc((*nfile)->ungetsize);
518 	if ((*nfile)->ungetbuf == NULL) {
519 		fclose((*nfile)->stream);
520 		free((*nfile)->name);
521 		free((*nfile));
522 		return got_error_from_errno2(__func__, "malloc");
523 	}
524 	TAILQ_INSERT_TAIL(&files, (*nfile), entry);
525 	return error;
526 }
527 
528 static const struct got_error*
529 new_remote(struct got_config_list_entry **gotconfig) {
530 	const struct got_error* error = NULL;
531 
532 	if (((*gotconfig) = calloc(1, sizeof(struct got_config_list_entry))) ==
533 	    NULL)
534 	    error = got_error_from_errno("calloc");
535 	return error;
536 }
537 
538 int
539 popfile(void)
540 {
541 	struct file	*prev = NULL;
542 
543 	TAILQ_REMOVE(&files, file, entry);
544 	fclose(file->stream);
545 	free(file->name);
546 	free(file->ungetbuf);
547 	free(file);
548 	file = prev;
549 	return (file ? 0 : EOF);
550 }
551 
552 const struct got_error*
553 parse_got_config(struct got_config_list **conf_list, char *filename)
554 {
555 	struct sym	*sym, *next;
556 
557 	*conf_list = NULL;
558 
559 	/*
560 	 * We don't require that gotconfig exists
561 	 * So, null gerror and goto done
562 	 */
563 	gerror = pushfile(&file, filename);
564 	if (gerror && gerror->code == GOT_ERR_NO_CONFIG_FILE) {
565 		gerror = NULL;
566 		goto done;
567 	}
568 	else if (gerror)
569 		return gerror;
570 
571 	TAILQ_INIT(&got_config_list);
572 	topfile = file;
573 
574 	yyparse();
575 	popfile();
576 
577 	/* Free macros and check which have not been used. */
578 	TAILQ_FOREACH_SAFE(sym, &symhead, entry, next) {
579 		if (!sym->persist) {
580 			free(sym->nam);
581 			free(sym->val);
582 			TAILQ_REMOVE(&symhead, sym, entry);
583 			free(sym);
584 		}
585 	}
586 done:
587 	*conf_list = &got_config_list;
588 	return gerror;
589 }
590 
591 int
592 symset(const char *nam, const char *val, int persist)
593 {
594 	struct sym	*sym;
595 
596 	TAILQ_FOREACH(sym, &symhead, entry) {
597 		if (strcmp(nam, sym->nam) == 0)
598 			break;
599 	}
600 
601 	if (sym != NULL) {
602 		if (sym->persist == 1)
603 			return (0);
604 		else {
605 			free(sym->nam);
606 			free(sym->val);
607 			TAILQ_REMOVE(&symhead, sym, entry);
608 			free(sym);
609 		}
610 	}
611 	if ((sym = calloc(1, sizeof(*sym))) == NULL)
612 		return (-1);
613 
614 	sym->nam = strdup(nam);
615 	if (sym->nam == NULL) {
616 		free(sym);
617 		return (-1);
618 	}
619 	sym->val = strdup(val);
620 	if (sym->val == NULL) {
621 		free(sym->nam);
622 		free(sym);
623 		return (-1);
624 	}
625 	sym->used = 0;
626 	sym->persist = persist;
627 	TAILQ_INSERT_TAIL(&symhead, sym, entry);
628 	return (0);
629 }
630 
631 int
632 cmdline_symset(char *s)
633 {
634 	char	*sym, *val;
635 	int	ret;
636 	size_t	len;
637 
638 	if ((val = strrchr(s, '=')) == NULL)
639 		return (-1);
640 
641 	len = strlen(s) - strlen(val) + 1;
642 	if ((sym = malloc(len)) == NULL)
643 		errx(1, "cmdline_symset: malloc");
644 
645 	strlcpy(sym, s, len);
646 
647 	ret = symset(sym, val + 1, 1);
648 	free(sym);
649 
650 	return (ret);
651 }
652 
653 char *
654 symget(const char *nam)
655 {
656 	struct sym	*sym;
657 
658 	TAILQ_FOREACH(sym, &symhead, entry) {
659 		if (strcmp(nam, sym->nam) == 0) {
660 			sym->used = 1;
661 			return (sym->val);
662 		}
663 	}
664 	return (NULL);
665 }