• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * libkmod - interface to kernel module operations
3  *
4  * Copyright (C) 2011-2013  ProFUSION embedded systems
5  * Copyright (C) 2013  Intel Corporation. All rights reserved.
6  *
7  * This library is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * This library is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
19  */
20 
21 #include <ctype.h>
22 #include <dirent.h>
23 #include <errno.h>
24 #include <stdarg.h>
25 #include <stddef.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <unistd.h>
30 #include <sys/stat.h>
31 #include <sys/types.h>
32 
33 #include <shared/util.h>
34 
35 #include "libkmod.h"
36 #include "libkmod-internal.h"
37 
38 struct kmod_alias {
39 	char *name;
40 	char modname[];
41 };
42 
43 struct kmod_options {
44 	char *options;
45 	char modname[];
46 };
47 
48 struct kmod_command {
49 	char *command;
50 	char modname[];
51 };
52 
53 struct kmod_softdep {
54 	char *name;
55 	const char **pre;
56 	const char **post;
57 	unsigned int n_pre;
58 	unsigned int n_post;
59 };
60 
kmod_blacklist_get_modname(const struct kmod_list * l)61 const char *kmod_blacklist_get_modname(const struct kmod_list *l)
62 {
63 	return l->data;
64 }
65 
kmod_alias_get_name(const struct kmod_list * l)66 const char *kmod_alias_get_name(const struct kmod_list *l) {
67 	const struct kmod_alias *alias = l->data;
68 	return alias->name;
69 }
70 
kmod_alias_get_modname(const struct kmod_list * l)71 const char *kmod_alias_get_modname(const struct kmod_list *l) {
72 	const struct kmod_alias *alias = l->data;
73 	return alias->modname;
74 }
75 
kmod_option_get_options(const struct kmod_list * l)76 const char *kmod_option_get_options(const struct kmod_list *l) {
77 	const struct kmod_options *alias = l->data;
78 	return alias->options;
79 }
80 
kmod_option_get_modname(const struct kmod_list * l)81 const char *kmod_option_get_modname(const struct kmod_list *l) {
82 	const struct kmod_options *alias = l->data;
83 	return alias->modname;
84 }
85 
kmod_command_get_command(const struct kmod_list * l)86 const char *kmod_command_get_command(const struct kmod_list *l) {
87 	const struct kmod_command *alias = l->data;
88 	return alias->command;
89 }
90 
kmod_command_get_modname(const struct kmod_list * l)91 const char *kmod_command_get_modname(const struct kmod_list *l) {
92 	const struct kmod_command *alias = l->data;
93 	return alias->modname;
94 }
95 
kmod_softdep_get_name(const struct kmod_list * l)96 const char *kmod_softdep_get_name(const struct kmod_list *l) {
97 	const struct kmod_softdep *dep = l->data;
98 	return dep->name;
99 }
100 
kmod_softdep_get_pre(const struct kmod_list * l,unsigned int * count)101 const char * const *kmod_softdep_get_pre(const struct kmod_list *l, unsigned int *count) {
102 	const struct kmod_softdep *dep = l->data;
103 	*count = dep->n_pre;
104 	return dep->pre;
105 }
106 
kmod_softdep_get_post(const struct kmod_list * l,unsigned int * count)107 const char * const *kmod_softdep_get_post(const struct kmod_list *l, unsigned int *count) {
108 	const struct kmod_softdep *dep = l->data;
109 	*count = dep->n_post;
110 	return dep->post;
111 }
112 
kmod_config_add_command(struct kmod_config * config,const char * modname,const char * command,const char * command_name,struct kmod_list ** list)113 static int kmod_config_add_command(struct kmod_config *config,
114 						const char *modname,
115 						const char *command,
116 						const char *command_name,
117 						struct kmod_list **list)
118 {
119 	_cleanup_free_ struct kmod_command *cmd;
120 	struct kmod_list *l;
121 	size_t modnamelen = strlen(modname) + 1;
122 	size_t commandlen = strlen(command) + 1;
123 
124 	DBG(config->ctx, "modname='%s' cmd='%s %s'\n", modname, command_name,
125 								command);
126 
127 	cmd = malloc(sizeof(*cmd) + modnamelen + commandlen);
128 	if (!cmd)
129 		return -ENOMEM;
130 
131 	cmd->command = sizeof(*cmd) + modnamelen + (char *)cmd;
132 	memcpy(cmd->modname, modname, modnamelen);
133 	memcpy(cmd->command, command, commandlen);
134 
135 	l = kmod_list_append(*list, cmd);
136 	if (!l)
137 		return -ENOMEM;
138 
139 	*list = l;
140 	cmd = NULL;
141 	return 0;
142 }
143 
kmod_config_free_command(struct kmod_config * config,struct kmod_list * l,struct kmod_list ** list)144 static void kmod_config_free_command(struct kmod_config *config,
145 					struct kmod_list *l,
146 					struct kmod_list **list)
147 {
148 	struct kmod_command *cmd = l->data;
149 
150 	free(cmd);
151 	*list = kmod_list_remove(l);
152 }
153 
kmod_config_add_options(struct kmod_config * config,const char * modname,const char * options)154 static int kmod_config_add_options(struct kmod_config *config,
155 				const char *modname, const char *options)
156 {
157 	_cleanup_free_ struct kmod_options *opt;
158 	struct kmod_list *list;
159 	size_t modnamelen = strlen(modname) + 1;
160 	size_t optionslen = strlen(options) + 1;
161 
162 	DBG(config->ctx, "modname='%s' options='%s'\n", modname, options);
163 
164 	opt = malloc(sizeof(*opt) + modnamelen + optionslen);
165 	if (!opt)
166 		return -ENOMEM;
167 
168 	opt->options = sizeof(*opt) + modnamelen + (char *)opt;
169 
170 	memcpy(opt->modname, modname, modnamelen);
171 	memcpy(opt->options, options, optionslen);
172 	strchr_replace(opt->options, '\t', ' ');
173 
174 	list = kmod_list_append(config->options, opt);
175 	if (!list)
176 		return -ENOMEM;
177 
178 	opt = NULL;
179 	config->options = list;
180 	return 0;
181 }
182 
kmod_config_free_options(struct kmod_config * config,struct kmod_list * l)183 static void kmod_config_free_options(struct kmod_config *config,
184 							struct kmod_list *l)
185 {
186 	struct kmod_options *opt = l->data;
187 
188 	free(opt);
189 
190 	config->options = kmod_list_remove(l);
191 }
192 
kmod_config_add_alias(struct kmod_config * config,const char * name,const char * modname)193 static int kmod_config_add_alias(struct kmod_config *config,
194 					const char *name, const char *modname)
195 {
196 	_cleanup_free_ struct kmod_alias *alias;
197 	struct kmod_list *list;
198 	size_t namelen = strlen(name) + 1, modnamelen = strlen(modname) + 1;
199 
200 	DBG(config->ctx, "name=%s modname=%s\n", name, modname);
201 
202 	alias = malloc(sizeof(*alias) + namelen + modnamelen);
203 	if (!alias)
204 		return -ENOMEM;
205 
206 	alias->name = sizeof(*alias) + modnamelen + (char *)alias;
207 
208 	memcpy(alias->modname, modname, modnamelen);
209 	memcpy(alias->name, name, namelen);
210 
211 	list = kmod_list_append(config->aliases, alias);
212 	if (!list)
213 		return -ENOMEM;
214 
215 	alias = NULL;
216 	config->aliases = list;
217 	return 0;
218 }
219 
kmod_config_free_alias(struct kmod_config * config,struct kmod_list * l)220 static void kmod_config_free_alias(struct kmod_config *config,
221 							struct kmod_list *l)
222 {
223 	struct kmod_alias *alias = l->data;
224 
225 	free(alias);
226 
227 	config->aliases = kmod_list_remove(l);
228 }
229 
kmod_config_add_blacklist(struct kmod_config * config,const char * modname)230 static int kmod_config_add_blacklist(struct kmod_config *config,
231 							const char *modname)
232 {
233 	_cleanup_free_ char *p;
234 	struct kmod_list *list;
235 
236 	DBG(config->ctx, "modname=%s\n", modname);
237 
238 	p = strdup(modname);
239 	if (!p)
240 		return -ENOMEM;
241 
242 	list = kmod_list_append(config->blacklists, p);
243 	if (!list)
244 		return -ENOMEM;
245 
246 	p = NULL;
247 	config->blacklists = list;
248 	return 0;
249 }
250 
kmod_config_free_blacklist(struct kmod_config * config,struct kmod_list * l)251 static void kmod_config_free_blacklist(struct kmod_config *config,
252 							struct kmod_list *l)
253 {
254 	free(l->data);
255 	config->blacklists = kmod_list_remove(l);
256 }
257 
kmod_config_add_softdep(struct kmod_config * config,const char * modname,const char * line)258 static int kmod_config_add_softdep(struct kmod_config *config,
259 							const char *modname,
260 							const char *line)
261 {
262 	struct kmod_list *list;
263 	struct kmod_softdep *dep;
264 	const char *s, *p;
265 	char *itr;
266 	unsigned int n_pre = 0, n_post = 0;
267 	size_t modnamelen = strlen(modname) + 1;
268 	size_t buflen = 0;
269 	bool was_space = false;
270 	enum { S_NONE, S_PRE, S_POST } mode = S_NONE;
271 
272 	DBG(config->ctx, "modname=%s\n", modname);
273 
274 	/* analyze and count */
275 	for (p = s = line; ; s++) {
276 		size_t plen;
277 
278 		if (*s != '\0') {
279 			if (!isspace(*s)) {
280 				was_space = false;
281 				continue;
282 			}
283 
284 			if (was_space) {
285 				p = s + 1;
286 				continue;
287 			}
288 			was_space = true;
289 
290 			if (p >= s)
291 				continue;
292 		}
293 		plen = s - p;
294 
295 		if (plen == sizeof("pre:") - 1 &&
296 				memcmp(p, "pre:", sizeof("pre:") - 1) == 0)
297 			mode = S_PRE;
298 		else if (plen == sizeof("post:") - 1 &&
299 				memcmp(p, "post:", sizeof("post:") - 1) == 0)
300 			mode = S_POST;
301 		else if (*s != '\0' || (*s == '\0' && !was_space)) {
302 			if (mode == S_PRE) {
303 				buflen += plen + 1;
304 				n_pre++;
305 			} else if (mode == S_POST) {
306 				buflen += plen + 1;
307 				n_post++;
308 			}
309 		}
310 		p = s + 1;
311 		if (*s == '\0')
312 			break;
313 	}
314 
315 	DBG(config->ctx, "%u pre, %u post\n", n_pre, n_post);
316 
317 	dep = malloc(sizeof(struct kmod_softdep) + modnamelen +
318 		     n_pre * sizeof(const char *) +
319 		     n_post * sizeof(const char *) +
320 		     buflen);
321 	if (dep == NULL) {
322 		ERR(config->ctx, "out-of-memory modname=%s\n", modname);
323 		return -ENOMEM;
324 	}
325 	dep->n_pre = n_pre;
326 	dep->n_post = n_post;
327 	dep->pre = (const char **)((char *)dep + sizeof(struct kmod_softdep));
328 	dep->post = dep->pre + n_pre;
329 	dep->name = (char *)(dep->post + n_post);
330 
331 	memcpy(dep->name, modname, modnamelen);
332 
333 	/* copy strings */
334 	itr = dep->name + modnamelen;
335 	n_pre = 0;
336 	n_post = 0;
337 	mode = S_NONE;
338 	was_space = false;
339 	for (p = s = line; ; s++) {
340 		size_t plen;
341 
342 		if (*s != '\0') {
343 			if (!isspace(*s)) {
344 				was_space = false;
345 				continue;
346 			}
347 
348 			if (was_space) {
349 				p = s + 1;
350 				continue;
351 			}
352 			was_space = true;
353 
354 			if (p >= s)
355 				continue;
356 		}
357 		plen = s - p;
358 
359 		if (plen == sizeof("pre:") - 1 &&
360 				memcmp(p, "pre:", sizeof("pre:") - 1) == 0)
361 			mode = S_PRE;
362 		else if (plen == sizeof("post:") - 1 &&
363 				memcmp(p, "post:", sizeof("post:") - 1) == 0)
364 			mode = S_POST;
365 		else if (*s != '\0' || (*s == '\0' && !was_space)) {
366 			if (mode == S_PRE) {
367 				dep->pre[n_pre] = itr;
368 				memcpy(itr, p, plen);
369 				itr[plen] = '\0';
370 				itr += plen + 1;
371 				n_pre++;
372 			} else if (mode == S_POST) {
373 				dep->post[n_post] = itr;
374 				memcpy(itr, p, plen);
375 				itr[plen] = '\0';
376 				itr += plen + 1;
377 				n_post++;
378 			}
379 		}
380 		p = s + 1;
381 		if (*s == '\0')
382 			break;
383 	}
384 
385 	list = kmod_list_append(config->softdeps, dep);
386 	if (list == NULL) {
387 		free(dep);
388 		return -ENOMEM;
389 	}
390 	config->softdeps = list;
391 
392 	return 0;
393 }
394 
softdep_to_char(struct kmod_softdep * dep)395 static char *softdep_to_char(struct kmod_softdep *dep) {
396 	const size_t sz_preprefix = sizeof("pre: ") - 1;
397 	const size_t sz_postprefix = sizeof("post: ") - 1;
398 	size_t sz = 1; /* at least '\0' */
399 	size_t sz_pre, sz_post;
400 	const char *start, *end;
401 	char *s, *itr;
402 
403 	/*
404 	 * Rely on the fact that dep->pre[] and dep->post[] are strv's that
405 	 * point to a contiguous buffer
406 	 */
407 	if (dep->n_pre > 0) {
408 		start = dep->pre[0];
409 		end = dep->pre[dep->n_pre - 1]
410 					+ strlen(dep->pre[dep->n_pre - 1]);
411 		sz_pre = end - start;
412 		sz += sz_pre + sz_preprefix;
413 	} else
414 		sz_pre = 0;
415 
416 	if (dep->n_post > 0) {
417 		start = dep->post[0];
418 		end = dep->post[dep->n_post - 1]
419 					+ strlen(dep->post[dep->n_post - 1]);
420 		sz_post = end - start;
421 		sz += sz_post + sz_postprefix;
422 	} else
423 		sz_post = 0;
424 
425 	itr = s = malloc(sz);
426 	if (s == NULL)
427 		return NULL;
428 
429 	if (sz_pre) {
430 		char *p;
431 
432 		memcpy(itr, "pre: ", sz_preprefix);
433 		itr += sz_preprefix;
434 
435 		/* include last '\0' */
436 		memcpy(itr, dep->pre[0], sz_pre + 1);
437 		for (p = itr; p < itr + sz_pre; p++) {
438 			if (*p == '\0')
439 				*p = ' ';
440 		}
441 		itr = p;
442 	}
443 
444 	if (sz_post) {
445 		char *p;
446 
447 		memcpy(itr, "post: ", sz_postprefix);
448 		itr += sz_postprefix;
449 
450 		/* include last '\0' */
451 		memcpy(itr, dep->post[0], sz_post + 1);
452 		for (p = itr; p < itr + sz_post; p++) {
453 			if (*p == '\0')
454 				*p = ' ';
455 		}
456 		itr = p;
457 	}
458 
459 	*itr = '\0';
460 
461 	return s;
462 }
463 
kmod_config_free_softdep(struct kmod_config * config,struct kmod_list * l)464 static void kmod_config_free_softdep(struct kmod_config *config,
465 							struct kmod_list *l)
466 {
467 	free(l->data);
468 	config->softdeps = kmod_list_remove(l);
469 }
470 
kcmdline_parse_result(struct kmod_config * config,char * modname,char * param,char * value)471 static void kcmdline_parse_result(struct kmod_config *config, char *modname,
472 						char *param, char *value)
473 {
474 	if (modname == NULL || param == NULL)
475 		return;
476 
477 	DBG(config->ctx, "%s %s\n", modname, param);
478 
479 	if (streq(modname, "modprobe") && !strncmp(param, "blacklist=", 10)) {
480 		for (;;) {
481 			char *t = strsep(&value, ",");
482 			if (t == NULL)
483 				break;
484 
485 			kmod_config_add_blacklist(config, t);
486 		}
487 	} else {
488 		if (underscores(modname) < 0) {
489 			ERR(config->ctx, "Ignoring bad option on kernel command line while parsing module name: '%s'\n",
490 			    modname);
491 		} else {
492 			kmod_config_add_options(config, modname, param);
493 		}
494 	}
495 }
496 
kmod_config_parse_kcmdline(struct kmod_config * config)497 static int kmod_config_parse_kcmdline(struct kmod_config *config)
498 {
499 	char buf[KCMD_LINE_SIZE];
500 	int fd, err;
501 	char *p, *p_quote_start, *modname,  *param = NULL, *value = NULL;
502 	bool is_quoted = false, iter = true;
503 	enum state {
504 		STATE_IGNORE,
505 		STATE_MODNAME,
506 		STATE_PARAM,
507 		STATE_VALUE,
508 		STATE_COMPLETE,
509 	} state;
510 
511 	fd = open("/proc/cmdline", O_RDONLY|O_CLOEXEC);
512 	if (fd < 0) {
513 		err = -errno;
514 		DBG(config->ctx, "could not open '/proc/cmdline' for reading: %m\n");
515 		return err;
516 	}
517 
518 	err = read_str_safe(fd, buf, sizeof(buf));
519 	close(fd);
520 	if (err < 0) {
521 		ERR(config->ctx, "could not read from '/proc/cmdline': %s\n",
522 							strerror(-err));
523 		return err;
524 	}
525 
526 	state = STATE_MODNAME;
527 	p_quote_start = NULL;
528 	for (p = buf, modname = buf; iter; p++) {
529 		switch (*p) {
530 		case '"':
531 			is_quoted = !is_quoted;
532 
533 			/*
534 			 * only allow starting quote as first char when looking
535 			 * for a modname: anything else is considered ill-formed
536 			 */
537 			if (is_quoted && state == STATE_MODNAME && p == modname) {
538 				p_quote_start = p;
539 				modname = p + 1;
540 			} else if (state != STATE_VALUE) {
541 				state = STATE_IGNORE;
542 			}
543 
544 			break;
545 		case '\0':
546 			iter = false;
547 			/* fall-through */
548 		case ' ':
549 		case '\n':
550 		case '\t':
551 		case '\v':
552 		case '\f':
553 		case '\r':
554 			if (is_quoted && state == STATE_VALUE) {
555 				/* no state change*/;
556 			} else if (is_quoted) {
557 				/* spaces are only allowed in the value part */
558 				state = STATE_IGNORE;
559 			} else if (state == STATE_VALUE || state == STATE_PARAM) {
560 				*p = '\0';
561 				state = STATE_COMPLETE;
562 			} else {
563 				/*
564 				 * go to next option, ignoring any possible
565 				 * partial match we have
566 				 */
567 				modname = p + 1;
568 				state = STATE_MODNAME;
569 				p_quote_start = NULL;
570 			}
571 			break;
572 		case '.':
573 			if (state == STATE_MODNAME) {
574 				*p = '\0';
575 				param = p + 1;
576 				state = STATE_PARAM;
577 			} else if (state == STATE_PARAM) {
578 				state = STATE_IGNORE;
579 			}
580 			break;
581 		case '=':
582 			if (state == STATE_PARAM) {
583 				/*
584 				 * Don't set *p to '\0': the value var shadows
585 				 * param
586 				 */
587 				value = p + 1;
588 				state = STATE_VALUE;
589 			} else if (state == STATE_MODNAME) {
590 				state = STATE_IGNORE;
591 			}
592 			break;
593 		}
594 
595 		if (state == STATE_COMPLETE) {
596 			/*
597 			 * We may need to re-quote to unmangle what the
598 			 * bootloader passed. Example: grub passes the option as
599 			 * "parport.dyndbg=file drivers/parport/ieee1284_ops.c +mpf"
600 			 * instead of
601 			 * parport.dyndbg="file drivers/parport/ieee1284_ops.c +mpf"
602 			 */
603 			if (p_quote_start && p_quote_start < modname) {
604 				/*
605 				 * p_quote_start
606 				 * |
607 				 * |modname  param  value
608 				 * ||        |      |
609 				 * vv        v      v
610 				 * "parport\0dyndbg=file drivers/parport/ieee1284_ops.c +mpf" */
611 				memmove(p_quote_start, modname, value - modname);
612 				value--; modname--; param--;
613 				*value = '"';
614 			}
615 			kcmdline_parse_result(config, modname, param, value);
616 			/* start over on next iteration */
617 			modname = p + 1;
618 			state = STATE_MODNAME;
619 			p_quote_start = NULL;
620 		}
621 	}
622 
623 	return 0;
624 }
625 
626 /*
627  * Take an fd and own it. It will be closed on return. filename is used only
628  * for debug messages
629  */
kmod_config_parse(struct kmod_config * config,int fd,const char * filename)630 static int kmod_config_parse(struct kmod_config *config, int fd,
631 							const char *filename)
632 {
633 	struct kmod_ctx *ctx = config->ctx;
634 	char *line;
635 	FILE *fp;
636 	unsigned int linenum = 0;
637 	int err;
638 
639 	fp = fdopen(fd, "r");
640 	if (fp == NULL) {
641 		err = -errno;
642 		ERR(config->ctx, "fd %d: %m\n", fd);
643 		close(fd);
644 		return err;
645 	}
646 
647 	while ((line = freadline_wrapped(fp, &linenum)) != NULL) {
648 		char *cmd, *saveptr;
649 
650 		if (line[0] == '\0' || line[0] == '#')
651 			goto done_next;
652 
653 		cmd = strtok_r(line, "\t ", &saveptr);
654 		if (cmd == NULL)
655 			goto done_next;
656 
657 		if (streq(cmd, "alias")) {
658 			char *alias = strtok_r(NULL, "\t ", &saveptr);
659 			char *modname = strtok_r(NULL, "\t ", &saveptr);
660 
661 			if (underscores(alias) < 0 || underscores(modname) < 0)
662 				goto syntax_error;
663 
664 			kmod_config_add_alias(config, alias, modname);
665 		} else if (streq(cmd, "blacklist")) {
666 			char *modname = strtok_r(NULL, "\t ", &saveptr);
667 
668 			if (underscores(modname) < 0)
669 				goto syntax_error;
670 
671 			kmod_config_add_blacklist(config, modname);
672 		} else if (streq(cmd, "options")) {
673 			char *modname = strtok_r(NULL, "\t ", &saveptr);
674 			char *options = strtok_r(NULL, "\0", &saveptr);
675 
676 			if (underscores(modname) < 0 || options == NULL)
677 				goto syntax_error;
678 
679 			kmod_config_add_options(config, modname, options);
680 		} else if (streq(cmd, "install")) {
681 			char *modname = strtok_r(NULL, "\t ", &saveptr);
682 			char *installcmd = strtok_r(NULL, "\0", &saveptr);
683 
684 			if (underscores(modname) < 0 || installcmd == NULL)
685 				goto syntax_error;
686 
687 			kmod_config_add_command(config, modname, installcmd,
688 					cmd, &config->install_commands);
689 		} else if (streq(cmd, "remove")) {
690 			char *modname = strtok_r(NULL, "\t ", &saveptr);
691 			char *removecmd = strtok_r(NULL, "\0", &saveptr);
692 
693 			if (underscores(modname) < 0 || removecmd == NULL)
694 				goto syntax_error;
695 
696 			kmod_config_add_command(config, modname, removecmd,
697 					cmd, &config->remove_commands);
698 		} else if (streq(cmd, "softdep")) {
699 			char *modname = strtok_r(NULL, "\t ", &saveptr);
700 			char *softdeps = strtok_r(NULL, "\0", &saveptr);
701 
702 			if (underscores(modname) < 0 || softdeps == NULL)
703 				goto syntax_error;
704 
705 			kmod_config_add_softdep(config, modname, softdeps);
706 		} else if (streq(cmd, "include")
707 				|| streq(cmd, "config")) {
708 			ERR(ctx, "%s: command %s is deprecated and not parsed anymore\n",
709 								filename, cmd);
710 		} else {
711 syntax_error:
712 			ERR(ctx, "%s line %u: ignoring bad line starting with '%s'\n",
713 						filename, linenum, cmd);
714 		}
715 
716 done_next:
717 		free(line);
718 	}
719 
720 	fclose(fp);
721 
722 	return 0;
723 }
724 
kmod_config_free(struct kmod_config * config)725 void kmod_config_free(struct kmod_config *config)
726 {
727 	while (config->aliases)
728 		kmod_config_free_alias(config, config->aliases);
729 
730 	while (config->blacklists)
731 		kmod_config_free_blacklist(config, config->blacklists);
732 
733 	while (config->options)
734 		kmod_config_free_options(config, config->options);
735 
736 	while (config->install_commands) {
737 		kmod_config_free_command(config, config->install_commands,
738 						&config->install_commands);
739 	}
740 
741 	while (config->remove_commands) {
742 		kmod_config_free_command(config, config->remove_commands,
743 						&config->remove_commands);
744 	}
745 
746 	while (config->softdeps)
747 		kmod_config_free_softdep(config, config->softdeps);
748 
749 	for (; config->paths != NULL;
750 				config->paths = kmod_list_remove(config->paths))
751 		free(config->paths->data);
752 
753 	free(config);
754 }
755 
conf_files_filter_out(struct kmod_ctx * ctx,DIR * d,const char * path,const char * fn)756 static bool conf_files_filter_out(struct kmod_ctx *ctx, DIR *d,
757 					const char *path, const char *fn)
758 {
759 	size_t len = strlen(fn);
760 	struct stat st;
761 
762 	if (fn[0] == '.')
763 		return true;
764 
765 	if (len < 6 || (!streq(&fn[len - 5], ".conf")
766 				&& !streq(&fn[len - 6], ".alias")))
767 		return true;
768 
769 	fstatat(dirfd(d), fn, &st, 0);
770 
771 	if (S_ISDIR(st.st_mode)) {
772 		ERR(ctx, "Directories inside directories are not supported: "
773 							"%s/%s\n", path, fn);
774 		return true;
775 	}
776 
777 	return false;
778 }
779 
780 struct conf_file {
781 	const char *path;
782 	bool is_single;
783 	char name[];
784 };
785 
conf_files_insert_sorted(struct kmod_ctx * ctx,struct kmod_list ** list,const char * path,const char * name)786 static int conf_files_insert_sorted(struct kmod_ctx *ctx,
787 					struct kmod_list **list,
788 					const char *path, const char *name)
789 {
790 	struct kmod_list *lpos, *tmp;
791 	struct conf_file *cf;
792 	size_t namelen;
793 	int cmp = -1;
794 	bool is_single = false;
795 
796 	if (name == NULL) {
797 		name = basename(path);
798 		is_single = true;
799 	}
800 
801 	kmod_list_foreach(lpos, *list) {
802 		cf = lpos->data;
803 
804 		if ((cmp = strcmp(name, cf->name)) <= 0)
805 			break;
806 	}
807 
808 	if (cmp == 0) {
809 		DBG(ctx, "Ignoring duplicate config file: %s/%s\n", path,
810 									name);
811 		return -EEXIST;
812 	}
813 
814 	namelen = strlen(name);
815 	cf = malloc(sizeof(*cf) + namelen + 1);
816 	if (cf == NULL)
817 		return -ENOMEM;
818 
819 	memcpy(cf->name, name, namelen + 1);
820 	cf->path = path;
821 	cf->is_single = is_single;
822 
823 	if (lpos == NULL)
824 		tmp = kmod_list_append(*list, cf);
825 	else if (lpos == *list)
826 		tmp = kmod_list_prepend(*list, cf);
827 	else
828 		tmp = kmod_list_insert_before(lpos, cf);
829 
830 	if (tmp == NULL) {
831 		free(cf);
832 		return -ENOMEM;
833 	}
834 
835 	if (lpos == NULL || lpos == *list)
836 		*list = tmp;
837 
838 	return 0;
839 }
840 
841 /*
842  * Insert configuration files in @list, ignoring duplicates
843  */
conf_files_list(struct kmod_ctx * ctx,struct kmod_list ** list,const char * path,unsigned long long * path_stamp)844 static int conf_files_list(struct kmod_ctx *ctx, struct kmod_list **list,
845 						const char *path,
846 						unsigned long long *path_stamp)
847 {
848 	DIR *d;
849 	int err;
850 	struct stat st;
851 	struct dirent *dent;
852 
853 	if (stat(path, &st) != 0) {
854 		err = -errno;
855 		DBG(ctx, "could not stat '%s': %m\n", path);
856 		return err;
857 	}
858 
859 	*path_stamp = stat_mstamp(&st);
860 
861 	if (!S_ISDIR(st.st_mode)) {
862 		conf_files_insert_sorted(ctx, list, path, NULL);
863 		return 0;
864 	}
865 
866 	d = opendir(path);
867 	if (d == NULL) {
868 		ERR(ctx, "opendir(%s): %m\n", path);
869 		return -EINVAL;
870 	}
871 
872 	for (dent = readdir(d); dent != NULL; dent = readdir(d)) {
873 		if (conf_files_filter_out(ctx, d, path, dent->d_name))
874 			continue;
875 
876 		conf_files_insert_sorted(ctx, list, path, dent->d_name);
877 	}
878 
879 	closedir(d);
880 	return 0;
881 }
882 
kmod_config_new(struct kmod_ctx * ctx,struct kmod_config ** p_config,const char * const * config_paths)883 int kmod_config_new(struct kmod_ctx *ctx, struct kmod_config **p_config,
884 					const char * const *config_paths)
885 {
886 	struct kmod_config *config;
887 	struct kmod_list *list = NULL;
888 	struct kmod_list *path_list = NULL;
889 	size_t i;
890 
891 	conf_files_insert_sorted(ctx, &list, kmod_get_dirname(ctx), "modules.softdep");
892 
893 	for (i = 0; config_paths[i] != NULL; i++) {
894 		const char *path = config_paths[i];
895 		unsigned long long path_stamp = 0;
896 		size_t pathlen;
897 		struct kmod_list *tmp;
898 		struct kmod_config_path *cf;
899 
900 		if (conf_files_list(ctx, &list, path, &path_stamp) < 0)
901 			continue;
902 
903 		pathlen = strlen(path) + 1;
904 		cf = malloc(sizeof(*cf) + pathlen);
905 		if (cf == NULL)
906 			goto oom;
907 
908 		cf->stamp = path_stamp;
909 		memcpy(cf->path, path, pathlen);
910 
911 		tmp = kmod_list_append(path_list, cf);
912 		if (tmp == NULL) {
913 			free(cf);
914 			goto oom;
915 		}
916 		path_list = tmp;
917 	}
918 
919 	*p_config = config = calloc(1, sizeof(struct kmod_config));
920 	if (config == NULL)
921 		goto oom;
922 
923 	config->paths = path_list;
924 	config->ctx = ctx;
925 
926 	for (; list != NULL; list = kmod_list_remove(list)) {
927 		char buf[PATH_MAX];
928 		const char *fn = buf;
929 		struct conf_file *cf = list->data;
930 		int fd;
931 
932 		if (cf->is_single) {
933 			fn = cf->path;
934 		} else if (snprintf(buf, sizeof(buf), "%s/%s",
935 				    cf->path, cf->name) >= (int)sizeof(buf)) {
936 			ERR(ctx, "Error parsing %s/%s: path too long\n",
937 			    cf->path, cf->name);
938 			free(cf);
939 			continue;
940 		}
941 
942 		fd = open(fn, O_RDONLY|O_CLOEXEC);
943 		DBG(ctx, "parsing file '%s' fd=%d\n", fn, fd);
944 
945 		if (fd >= 0)
946 			kmod_config_parse(config, fd, fn);
947 
948 		free(cf);
949 	}
950 
951 	kmod_config_parse_kcmdline(config);
952 
953 	return 0;
954 
955 oom:
956 	for (; list != NULL; list = kmod_list_remove(list))
957 		free(list->data);
958 
959 	for (; path_list != NULL; path_list = kmod_list_remove(path_list))
960 		free(path_list->data);
961 
962 	return -ENOMEM;
963 }
964 
965 /**********************************************************************
966  * struct kmod_config_iter functions
967  **********************************************************************/
968 
969 enum config_type {
970 	CONFIG_TYPE_BLACKLIST = 0,
971 	CONFIG_TYPE_INSTALL,
972 	CONFIG_TYPE_REMOVE,
973 	CONFIG_TYPE_ALIAS,
974 	CONFIG_TYPE_OPTION,
975 	CONFIG_TYPE_SOFTDEP,
976 };
977 
978 struct kmod_config_iter {
979 	enum config_type type;
980 	bool intermediate;
981 	const struct kmod_list *list;
982 	const struct kmod_list *curr;
983 	void *data;
984 	const char *(*get_key)(const struct kmod_list *l);
985 	const char *(*get_value)(const struct kmod_list *l);
986 };
987 
softdep_get_plain_softdep(const struct kmod_list * l)988 static const char *softdep_get_plain_softdep(const struct kmod_list *l)
989 {
990 	char *s = softdep_to_char(l->data);
991 	return s;
992 }
993 
kmod_config_iter_new(const struct kmod_ctx * ctx,enum config_type type)994 static struct kmod_config_iter *kmod_config_iter_new(const struct kmod_ctx* ctx,
995 							enum config_type type)
996 {
997 	struct kmod_config_iter *iter = calloc(1, sizeof(*iter));
998 	const struct kmod_config *config = kmod_get_config(ctx);
999 
1000 	if (iter == NULL)
1001 		return NULL;
1002 
1003 	iter->type = type;
1004 
1005 	switch (type) {
1006 	case CONFIG_TYPE_BLACKLIST:
1007 		iter->list = config->blacklists;
1008 		iter->get_key = kmod_blacklist_get_modname;
1009 		break;
1010 	case CONFIG_TYPE_INSTALL:
1011 		iter->list = config->install_commands;
1012 		iter->get_key = kmod_command_get_modname;
1013 		iter->get_value = kmod_command_get_command;
1014 		break;
1015 	case CONFIG_TYPE_REMOVE:
1016 		iter->list = config->remove_commands;
1017 		iter->get_key = kmod_command_get_modname;
1018 		iter->get_value = kmod_command_get_command;
1019 		break;
1020 	case CONFIG_TYPE_ALIAS:
1021 		iter->list = config->aliases;
1022 		iter->get_key = kmod_alias_get_name;
1023 		iter->get_value = kmod_alias_get_modname;
1024 		break;
1025 	case CONFIG_TYPE_OPTION:
1026 		iter->list = config->options;
1027 		iter->get_key = kmod_option_get_modname;
1028 		iter->get_value = kmod_option_get_options;
1029 		break;
1030 	case CONFIG_TYPE_SOFTDEP:
1031 		iter->list = config->softdeps;
1032 		iter->get_key = kmod_softdep_get_name;
1033 		iter->get_value = softdep_get_plain_softdep;
1034 		iter->intermediate = true;
1035 		break;
1036 	}
1037 
1038 	return iter;
1039 }
1040 
1041 /**
1042  * SECTION:libkmod-config
1043  * @short_description: retrieve current libkmod configuration
1044  */
1045 
1046 /**
1047  * kmod_config_get_blacklists:
1048  * @ctx: kmod library context
1049  *
1050  * Retrieve an iterator to deal with the blacklist maintained inside the
1051  * library. See kmod_config_iter_get_key(), kmod_config_iter_get_value() and
1052  * kmod_config_iter_next(). At least one call to kmod_config_iter_next() must
1053  * be made to initialize the iterator and check if it's valid.
1054  *
1055  * Returns: a new iterator over the blacklists or NULL on failure. Free it
1056  * with kmod_config_iter_free_iter().
1057  */
kmod_config_get_blacklists(const struct kmod_ctx * ctx)1058 KMOD_EXPORT struct kmod_config_iter *kmod_config_get_blacklists(const struct kmod_ctx *ctx)
1059 {
1060 	if (ctx == NULL)
1061 		return NULL;;
1062 
1063 	return kmod_config_iter_new(ctx, CONFIG_TYPE_BLACKLIST);
1064 }
1065 
1066 /**
1067  * kmod_config_get_install_commands:
1068  * @ctx: kmod library context
1069  *
1070  * Retrieve an iterator to deal with the install commands maintained inside the
1071  * library. See kmod_config_iter_get_key(), kmod_config_iter_get_value() and
1072  * kmod_config_iter_next(). At least one call to kmod_config_iter_next() must
1073  * be made to initialize the iterator and check if it's valid.
1074  *
1075  * Returns: a new iterator over the install commands or NULL on failure. Free
1076  * it with kmod_config_iter_free_iter().
1077  */
kmod_config_get_install_commands(const struct kmod_ctx * ctx)1078 KMOD_EXPORT struct kmod_config_iter *kmod_config_get_install_commands(const struct kmod_ctx *ctx)
1079 {
1080 	if (ctx == NULL)
1081 		return NULL;;
1082 
1083 	return kmod_config_iter_new(ctx, CONFIG_TYPE_INSTALL);
1084 }
1085 
1086 /**
1087  * kmod_config_get_remove_commands:
1088  * @ctx: kmod library context
1089  *
1090  * Retrieve an iterator to deal with the remove commands maintained inside the
1091  * library. See kmod_config_iter_get_key(), kmod_config_iter_get_value() and
1092  * kmod_config_iter_next(). At least one call to kmod_config_iter_next() must
1093  * be made to initialize the iterator and check if it's valid.
1094  *
1095  * Returns: a new iterator over the remove commands or NULL on failure. Free
1096  * it with kmod_config_iter_free_iter().
1097  */
kmod_config_get_remove_commands(const struct kmod_ctx * ctx)1098 KMOD_EXPORT struct kmod_config_iter *kmod_config_get_remove_commands(const struct kmod_ctx *ctx)
1099 {
1100 	if (ctx == NULL)
1101 		return NULL;;
1102 
1103 	return kmod_config_iter_new(ctx, CONFIG_TYPE_REMOVE);
1104 }
1105 
1106 /**
1107  * kmod_config_get_aliases:
1108  * @ctx: kmod library context
1109  *
1110  * Retrieve an iterator to deal with the aliases maintained inside the
1111  * library. See kmod_config_iter_get_key(), kmod_config_iter_get_value() and
1112  * kmod_config_iter_next(). At least one call to kmod_config_iter_next() must
1113  * be made to initialize the iterator and check if it's valid.
1114  *
1115  * Returns: a new iterator over the aliases or NULL on failure. Free it with
1116  * kmod_config_iter_free_iter().
1117  */
kmod_config_get_aliases(const struct kmod_ctx * ctx)1118 KMOD_EXPORT struct kmod_config_iter *kmod_config_get_aliases(const struct kmod_ctx *ctx)
1119 {
1120 	if (ctx == NULL)
1121 		return NULL;;
1122 
1123 	return kmod_config_iter_new(ctx, CONFIG_TYPE_ALIAS);
1124 }
1125 
1126 /**
1127  * kmod_config_get_options:
1128  * @ctx: kmod library context
1129  *
1130  * Retrieve an iterator to deal with the options maintained inside the
1131  * library. See kmod_config_iter_get_key(), kmod_config_iter_get_value() and
1132  * kmod_config_iter_next(). At least one call to kmod_config_iter_next() must
1133  * be made to initialize the iterator and check if it's valid.
1134  *
1135  * Returns: a new iterator over the options or NULL on failure. Free it with
1136  * kmod_config_iter_free_iter().
1137  */
kmod_config_get_options(const struct kmod_ctx * ctx)1138 KMOD_EXPORT struct kmod_config_iter *kmod_config_get_options(const struct kmod_ctx *ctx)
1139 {
1140 	if (ctx == NULL)
1141 		return NULL;;
1142 
1143 	return kmod_config_iter_new(ctx, CONFIG_TYPE_OPTION);
1144 }
1145 
1146 /**
1147  * kmod_config_get_softdeps:
1148  * @ctx: kmod library context
1149  *
1150  * Retrieve an iterator to deal with the softdeps maintained inside the
1151  * library. See kmod_config_iter_get_key(), kmod_config_iter_get_value() and
1152  * kmod_config_iter_next(). At least one call to kmod_config_iter_next() must
1153  * be made to initialize the iterator and check if it's valid.
1154  *
1155  * Returns: a new iterator over the softdeps or NULL on failure. Free it with
1156  * kmod_config_iter_free_iter().
1157  */
kmod_config_get_softdeps(const struct kmod_ctx * ctx)1158 KMOD_EXPORT struct kmod_config_iter *kmod_config_get_softdeps(const struct kmod_ctx *ctx)
1159 {
1160 	if (ctx == NULL)
1161 		return NULL;;
1162 
1163 	return kmod_config_iter_new(ctx, CONFIG_TYPE_SOFTDEP);
1164 }
1165 
1166 /**
1167  * kmod_config_iter_get_key:
1168  * @iter: iterator over a certain configuration
1169  *
1170  * When using a new allocated iterator, user must perform a call to
1171  * kmod_config_iter_next() to initialize iterator's position and check if it's
1172  * valid.
1173  *
1174  * Returns: the key of the current configuration pointed by @iter.
1175  */
kmod_config_iter_get_key(const struct kmod_config_iter * iter)1176 KMOD_EXPORT const char *kmod_config_iter_get_key(const struct kmod_config_iter *iter)
1177 {
1178 	if (iter == NULL || iter->curr == NULL)
1179 		return NULL;
1180 
1181 	return iter->get_key(iter->curr);
1182 }
1183 
1184 /**
1185  * kmod_config_iter_get_value:
1186  * @iter: iterator over a certain configuration
1187  *
1188  * When using a new allocated iterator, user must perform a call to
1189  * kmod_config_iter_next() to initialize iterator's position and check if it's
1190  * valid.
1191  *
1192  * Returns: the value of the current configuration pointed by @iter.
1193  */
kmod_config_iter_get_value(const struct kmod_config_iter * iter)1194 KMOD_EXPORT const char *kmod_config_iter_get_value(const struct kmod_config_iter *iter)
1195 {
1196 	const char *s;
1197 
1198 	if (iter == NULL || iter->curr == NULL)
1199 		return NULL;
1200 
1201 	if (iter->get_value == NULL)
1202 		return NULL;
1203 
1204 	if (iter->intermediate) {
1205 		struct kmod_config_iter *i = (struct kmod_config_iter *)iter;
1206 
1207 		free(i->data);
1208 		s = i->data = (void *) iter->get_value(iter->curr);
1209 	} else
1210 		s = iter->get_value(iter->curr);
1211 
1212 	return s;
1213 }
1214 
1215 /**
1216  * kmod_config_iter_next:
1217  * @iter: iterator over a certain configuration
1218  *
1219  * Make @iter point to the next item of a certain configuration. It's an
1220  * automatically recycling iterator. When it reaches the end, false is
1221  * returned; then if user wants to iterate again, it's sufficient to call this
1222  * function once more.
1223  *
1224  * Returns: true if next position of @iter is valid or false if its end is
1225  * reached.
1226  */
kmod_config_iter_next(struct kmod_config_iter * iter)1227 KMOD_EXPORT bool kmod_config_iter_next(struct kmod_config_iter *iter)
1228 {
1229 	if (iter == NULL)
1230 		return false;
1231 
1232 	if (iter->curr == NULL) {
1233 		iter->curr = iter->list;
1234 		return iter->curr != NULL;
1235 	}
1236 
1237 	iter->curr = kmod_list_next(iter->list, iter->curr);
1238 
1239 	return iter->curr != NULL;
1240 }
1241 
1242 /**
1243  * kmod_config_iter_free_iter:
1244  * @iter: iterator over a certain configuration
1245  *
1246  * Free resources used by the iterator.
1247  */
kmod_config_iter_free_iter(struct kmod_config_iter * iter)1248 KMOD_EXPORT void kmod_config_iter_free_iter(struct kmod_config_iter *iter)
1249 {
1250 	free(iter->data);
1251 	free(iter);
1252 }
1253