1 /* vi: set sw=4 ts=4: */
3 * Modprobe written from scratch for BusyBox
5 * Copyright (c) 2002 by Robert Griebl, griebl@gmx.de
6 * Copyright (c) 2003 by Andrew Dennison, andrew.dennison@motec.com.au
7 * Copyright (c) 2005 by Jim Bauer, jfbauer@nfr.com
9 * Portions Copyright (c) 2005 by Yann E. MORIN, yann.morin.1998@anciens.enib.fr
11 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
15 #include <sys/utsname.h>
18 struct mod_opt_t { /* one-way list of options to pass to a module */
20 struct mod_opt_t * m_next;
23 struct dep_t { /* one-way list of dependency rules */
24 /* a dependency rule */
25 char * m_name; /* the module name*/
26 char * m_path; /* the module file path */
27 struct mod_opt_t * m_options; /* the module options */
29 int m_isalias : 1; /* the module is an alias */
30 int m_reserved : 15; /* stuffin' */
32 int m_depcnt : 16; /* the number of dependable module(s) */
33 char ** m_deparr; /* the list of dependable module(s) */
35 struct dep_t * m_next; /* the next dependency rule */
38 struct mod_list_t { /* two-way list of modules to process */
39 /* a module description */
42 struct mod_opt_t * m_options;
44 struct mod_list_t * m_prev;
45 struct mod_list_t * m_next;
49 static struct dep_t *depend;
51 #define main_options "acdklnqrst:vVC:"
52 #define INSERT_ALL 1 /* a */
53 #define DUMP_CONF_EXIT 2 /* c */
54 #define D_OPT_IGNORED 4 /* d */
55 #define AUTOCLEAN_FLG 8 /* k */
56 #define LIST_ALL 16 /* l */
57 #define SHOW_ONLY 32 /* n */
58 #define QUIET 64 /* q */
59 #define REMOVE_OPT 128 /* r */
60 #define DO_SYSLOG 256 /* s */
61 #define RESTRICT_DIR 512 /* t */
62 #define VERBOSE 1024 /* v */
63 #define VERSION_ONLY 2048 /* V */
64 #define CONFIG_FILE 4096 /* C */
66 #define autoclean (main_opts & AUTOCLEAN_FLG)
67 #define show_only (main_opts & SHOW_ONLY)
68 #define quiet (main_opts & QUIET)
69 #define remove_opt (main_opts & REMOVE_OPT)
70 #define do_syslog (main_opts & DO_SYSLOG)
71 #define verbose (main_opts & VERBOSE)
75 static int parse_tag_value(char *buffer, char **ptag, char **pvalue)
79 buffer = skip_whitespace(buffer);
81 while (!isspace(*value))
82 if (!*value) return 0;
85 value = skip_whitespace(value);
86 if (!*value) return 0;
95 * This function appends an option to a list
97 static struct mod_opt_t *append_option(struct mod_opt_t *opt_list, char *opt)
99 struct mod_opt_t *ol = opt_list;
105 ol->m_next = xmalloc(sizeof(struct mod_opt_t));
108 ol = opt_list = xmalloc(sizeof(struct mod_opt_t));
111 ol->m_opt_val = xstrdup(opt);
117 #if ENABLE_FEATURE_MODPROBE_MULTIPLE_OPTIONS
118 /* static char* parse_command_string(char* src, char **dst);
119 * src: pointer to string containing argument
120 * dst: pointer to where to store the parsed argument
121 * return value: the pointer to the first char after the parsed argument,
122 * NULL if there was no argument parsed (only trailing spaces).
123 * Note that memory is allocated with xstrdup when a new argument was
124 * parsed. Don't forget to free it!
126 #define ARG_EMPTY 0x00
127 #define ARG_IN_DQUOTES 0x01
128 #define ARG_IN_SQUOTES 0x02
129 static char *parse_command_string(char *src, char **dst)
131 int opt_status = ARG_EMPTY;
134 /* Dumb you, I have nothing to do... */
135 if (src == NULL) return src;
137 /* Skip leading spaces */
138 while (*src == ' ') {
141 /* Is the end of string reached? */
145 /* Reached the start of an argument
146 * By the way, we duplicate a little too much
147 * here but what is too much is freed later. */
148 *dst = tmp_str = xstrdup(src);
149 /* Get to the end of that argument */
150 while (*tmp_str != '\0'
151 && (*tmp_str != ' ' || (opt_status & (ARG_IN_DQUOTES | ARG_IN_SQUOTES)))
155 if (opt_status & ARG_IN_DQUOTES) {
156 /* Already in double quotes, keep current char as is */
158 /* shift left 1 char, until end of string: get rid of the opening/closing quotes */
159 memmove(tmp_str, tmp_str + 1, strlen(tmp_str));
160 /* mark me: we enter or leave single quotes */
161 opt_status ^= ARG_IN_SQUOTES;
162 /* Back one char, as we need to re-scan the new char there. */
167 if (opt_status & ARG_IN_SQUOTES) {
168 /* Already in single quotes, keep current char as is */
170 /* shift left 1 char, until end of string: get rid of the opening/closing quotes */
171 memmove(tmp_str, tmp_str + 1, strlen(tmp_str));
172 /* mark me: we enter or leave double quotes */
173 opt_status ^= ARG_IN_DQUOTES;
174 /* Back one char, as we need to re-scan the new char there. */
179 if (opt_status & ARG_IN_SQUOTES) {
180 /* Between single quotes: keep as is. */
182 switch (*(tmp_str+1)) {
191 /* We escaped a special character. For now, keep
192 * both the back-slash and the following char. */
196 /* We escaped a space or a single or double quote,
197 * or a back-slash, or a non-escapable char. Remove
198 * the '\' and keep the new current char as is. */
199 memmove(tmp_str, tmp_str + 1, strlen(tmp_str));
204 /* Any other char that is special shall appear here.
205 * Example: $ starts a variable
207 do_variable_expansion();
211 /* any other char is kept as is. */
214 tmp_str++; /* Go to next char */
215 src++; /* Go to next char to find the end of the argument. */
217 /* End of string, but still no ending quote */
218 if (opt_status & (ARG_IN_DQUOTES | ARG_IN_SQUOTES)) {
219 bb_error_msg_and_die("unterminated (single or double) quote in options list: %s", src);
222 *dst = xrealloc(*dst, (tmp_str - *dst));
226 #define parse_command_string(src, dst) (0)
227 #endif /* ENABLE_FEATURE_MODPROBE_MULTIPLE_OPTIONS */
230 * This function reads aliases and default module options from a configuration file
231 * (/etc/modprobe.conf syntax). It supports includes (only files, no directories).
233 static void include_conf(struct dep_t **first, struct dep_t **current, char *buffer, int buflen, int fd)
235 int continuation_line = 0;
237 // alias parsing is not 100% correct (no correct handling of continuation lines within an alias) !
239 while (reads(fd, buffer, buflen)) {
243 p = strchr(buffer, '#');
249 while (l && isspace(buffer[l-1])) {
255 continuation_line = 0;
259 if (!continuation_line) {
260 if ((strncmp(buffer, "alias", 5) == 0) && isspace(buffer[5])) {
263 if (parse_tag_value(buffer + 6, &alias, &mod)) {
264 /* handle alias as a module dependent on the aliased module */
266 (*first) = (*current) = xzalloc(sizeof(struct dep_t));
269 (*current)->m_next = xzalloc(sizeof(struct dep_t));
270 (*current) = (*current)->m_next;
272 (*current)->m_name = xstrdup(alias);
273 (*current)->m_isalias = 1;
275 if ((strcmp(mod, "off") == 0) || (strcmp(mod, "null") == 0)) {
276 (*current)->m_depcnt = 0;
277 (*current)->m_deparr = 0;
280 (*current)->m_depcnt = 1;
281 (*current)->m_deparr = xmalloc(1 * sizeof(char *));
282 (*current)->m_deparr[0] = xstrdup(mod);
284 (*current)->m_next = 0;
287 else if ((strncmp(buffer, "options", 7) == 0) && isspace(buffer[7])) {
290 /* split the line in the module/alias name, and options */
291 if (parse_tag_value(buffer + 8, &mod, &opt)) {
294 /* find the corresponding module */
295 for (dt = *first; dt; dt = dt->m_next) {
296 if (strcmp(dt->m_name, mod) == 0)
300 if (ENABLE_FEATURE_MODPROBE_MULTIPLE_OPTIONS) {
301 char* new_opt = NULL;
302 while ((opt = parse_command_string(opt, &new_opt))) {
303 dt->m_options = append_option(dt->m_options, new_opt);
306 dt->m_options = append_option(dt->m_options, opt);
311 else if ((strncmp(buffer, "include", 7) == 0) && isspace(buffer[7])) {
312 int fdi; char *filename;
314 filename = skip_whitespace(buffer + 8);
316 if ((fdi = open(filename, O_RDONLY)) >= 0) {
317 include_conf(first, current, buffer, buflen, fdi);
326 * This function builds a list of dependency rules from /lib/modules/`uname -r`\modules.dep.
327 * It then fills every modules and aliases with their default options, found by parsing
328 * modprobe.conf (or modules.conf, or conf.modules).
330 static struct dep_t *build_dep(void)
334 struct dep_t *first = 0;
335 struct dep_t *current = 0;
338 int continuation_line = 0;
342 bb_error_msg_and_die("can't determine kernel version");
345 if (un.release[0] == '2') {
346 k_version = un.release[2] - '0';
349 filename = xasprintf("/lib/modules/%s/modules.dep", un.release);
350 fd = open(filename, O_RDONLY);
351 if (ENABLE_FEATURE_CLEAN_UP)
354 /* Ok, that didn't work. Fall back to looking in /lib/modules */
355 fd = open("/lib/modules/modules.dep", O_RDONLY);
361 while (reads(fd, buffer, sizeof(buffer))) {
362 int l = strlen(buffer);
365 while (l > 0 && isspace(buffer[l-1])) {
371 continuation_line = 0;
375 /* Is this a new module dep description? */
376 if (!continuation_line) {
377 /* find the dep beginning */
378 char *col = strchr(buffer, ':');
382 /* This line is a dep description */
387 /* Find the beginning of the module file name */
389 mods = strrchr(buffer, '/');
392 mods = buffer; /* no path for this module */
394 mods++; /* there was a path for this module... */
396 /* find the path of the module */
397 modpath = strchr(buffer, '/'); /* ... and this is the path */
399 modpath = buffer; /* module with no path */
400 /* find the end of the module name in the file name */
401 if (ENABLE_FEATURE_2_6_MODULES &&
402 (k_version > 4) && (*(col-3) == '.') &&
403 (*(col-2) == 'k') && (*(col-1) == 'o'))
406 if ((*(col-2) == '.') && (*(col-1) == 'o'))
409 mod = xstrndup(mods, dot - mods);
411 /* enqueue new module */
413 first = current = xmalloc(sizeof(struct dep_t));
416 current->m_next = xmalloc(sizeof(struct dep_t));
417 current = current->m_next;
419 current->m_name = mod;
420 current->m_path = xstrdup(modpath);
421 current->m_options = NULL;
422 current->m_isalias = 0;
423 current->m_depcnt = 0;
424 current->m_deparr = 0;
430 /* this line is not a dep description */
434 /* It's a dep description continuation */
437 while (p && *p && isblank(*p))
440 /* p points to the first dependable module; if NULL, no dependable module */
442 char *end = &buffer[l-1];
448 while (isblank(*end) || (*end == '\\'))
452 /* search the end of the dependency */
453 next = strchr(p, ' ');
461 /* find the beginning of the module file name */
462 deps = strrchr(p, '/');
464 if (!deps || (deps < p)) {
467 while (isblank(*deps))
472 /* find the end of the module name in the file name */
473 if (ENABLE_FEATURE_2_6_MODULES
474 && (k_version > 4) && (*(next-2) == '.')
475 && (*(next-1) == 'k') && (*next == 'o'))
478 if ((*(next-1) == '.') && (*next == 'o'))
481 /* Cope with blank lines */
482 if ((next-deps-ext+1) <= 0)
484 dep = xstrndup(deps, next - deps - ext + 1);
486 /* Add the new dependable module name */
488 current->m_deparr = xrealloc(current->m_deparr,
489 sizeof(char *) * current->m_depcnt);
490 current->m_deparr[current->m_depcnt - 1] = dep;
493 } while (next < end);
496 /* is there other dependable module(s) ? */
497 if (buffer[l-1] == '\\')
498 continuation_line = 1;
500 continuation_line = 0;
505 * First parse system-specific options and aliases
506 * as they take precedence over the kernel ones.
508 if (!ENABLE_FEATURE_2_6_MODULES
509 || (fd = open("/etc/modprobe.conf", O_RDONLY)) < 0)
510 if ((fd = open("/etc/modules.conf", O_RDONLY)) < 0)
511 fd = open("/etc/conf.modules", O_RDONLY);
514 include_conf(&first, ¤t, buffer, sizeof(buffer), fd);
518 /* Only 2.6 has a modules.alias file */
519 if (ENABLE_FEATURE_2_6_MODULES) {
520 /* Parse kernel-declared aliases */
521 filename = xasprintf("/lib/modules/%s/modules.alias", un.release);
522 fd = open(filename, O_RDONLY);
524 /* Ok, that didn't work. Fall back to looking in /lib/modules */
525 fd = open("/lib/modules/modules.alias", O_RDONLY);
527 if (ENABLE_FEATURE_CLEAN_UP)
531 include_conf(&first, ¤t, buffer, sizeof(buffer), fd);
539 /* return 1 = loaded, 0 = not loaded, -1 = can't tell */
540 static int already_loaded(const char *name)
545 fd = open("/proc/modules", O_RDONLY);
549 while (reads(fd, buffer, sizeof(buffer))) {
552 p = strchr (buffer, ' ');
556 // Truncate buffer at first space and check for matches, with
557 // the idiosyncrasy that _ and - are interchangeable because the
558 // 2.6 kernel does weird things.
561 for (p = buffer, n = name; ; p++, n++) {
563 if ((*p == '_' || *p == '-') && (*n == '_' || *n == '-'))
567 // If we made it to the end, that's a match.
580 static int mod_process(struct mod_list_t *list, int do_insert)
584 struct mod_opt_t *opts;
585 int argc_malloc; /* never used when CONFIG_FEATURE_CLEAN_UP not defined */
590 if (ENABLE_FEATURE_CLEAN_UP)
592 /* If CONFIG_FEATURE_CLEAN_UP is not defined, then we leak memory
593 * each time we allocate memory for argv.
594 * But it is (quite) small amounts of memory that leak each
595 * time a module is loaded, and it is reclaimed when modprobe
596 * exits anyway (even when standalone shell?).
597 * This could become a problem when loading a module with LOTS of
598 * dependencies, with LOTS of options for each dependencies, with
599 * very little memory on the target... But in that case, the module
600 * would not load because there is no more memory, so there's no
602 /* enough for minimal insmod (5 args + NULL) or rmmod (3 args + NULL) */
603 argv = xmalloc(6 * sizeof(char*));
605 if (already_loaded(list->m_name) != 1) {
606 argv[argc++] = "insmod";
607 if (ENABLE_FEATURE_2_4_MODULES) {
614 else if (verbose) /* verbose and quiet are mutually exclusive */
617 argv[argc++] = list->m_path;
618 if (ENABLE_FEATURE_CLEAN_UP)
620 opts = list->m_options;
622 /* Add one more option */
624 argv = xrealloc(argv,(argc + 1)* sizeof(char*));
625 argv[argc-1] = opts->m_opt_val;
630 /* modutils uses short name for removal */
631 if (already_loaded(list->m_name) != 0) {
632 argv[argc++] = "rmmod";
635 argv[argc++] = list->m_name;
636 if (ENABLE_FEATURE_CLEAN_UP)
644 printf("%s module %s\n", do_insert?"Loading":"Unloading", list->m_name);
647 int rc2 = wait4pid(spawn(argv));
650 rc = rc2; /* only last module matters */
653 rc = 0; /* success if remove any mod */
656 if (ENABLE_FEATURE_CLEAN_UP) {
657 /* the last value in the array has index == argc, but
658 * it is the terminating NULL, so we must not free it. */
659 while (argc_malloc < argc) {
660 free(argv[argc_malloc++]);
664 if (ENABLE_FEATURE_CLEAN_UP) {
668 list = do_insert ? list->m_prev : list->m_next;
670 return (show_only) ? 0 : rc;
674 * Check the matching between a pattern and a module name.
675 * We need this as *_* is equivalent to *-*, even in pattern matching.
677 static int check_pattern(const char* pat_src, const char* mod_src) {
680 if (ENABLE_FEATURE_MODPROBE_FANCY_ALIAS) {
685 pat = xstrdup (pat_src);
686 mod = xstrdup (mod_src);
688 for (p = pat; (p = strchr(p, '-')); *p++ = '_');
689 for (p = mod; (p = strchr(p, '-')); *p++ = '_');
691 ret = fnmatch(pat, mod, 0);
693 if (ENABLE_FEATURE_CLEAN_UP) {
700 return fnmatch(pat_src, mod_src, 0);
705 * Builds the dependency list (aka stack) of a module.
706 * head: the highest module in the stack (last to insmod, first to rmmod)
707 * tail: the lowest module in the stack (first to insmod, last to rmmod)
709 static void check_dep(char *mod, struct mod_list_t **head, struct mod_list_t **tail)
711 struct mod_list_t *find;
713 struct mod_opt_t *opt = 0;
716 /* Search for the given module name amongst all dependency rules.
717 * The module name in a dependency rule can be a shell pattern,
718 * so try to match the given module name against such a pattern.
719 * Of course if the name in the dependency rule is a plain string,
720 * then we consider it a pattern, and matching will still work. */
721 for (dt = depend; dt; dt = dt->m_next) {
722 if (check_pattern(dt->m_name, mod) == 0) {
728 bb_error_msg("module %s not found", mod);
732 // resolve alias names
733 while (dt->m_isalias) {
734 if (dt->m_depcnt == 1) {
737 for (adt = depend; adt; adt = adt->m_next) {
738 if (check_pattern(adt->m_name, dt->m_deparr[0]) == 0)
742 /* This is the module we are aliased to */
743 struct mod_opt_t *opts = dt->m_options;
744 /* Option of the alias are appended to the options of the module */
746 adt->m_options = append_option(adt->m_options, opts->m_opt_val);
752 bb_error_msg("module %s not found", mod);
757 bb_error_msg("bad alias %s", dt->m_name);
766 // search for duplicates
767 for (find = *head; find; find = find->m_next) {
768 if (!strcmp(mod, find->m_name)) {
769 // found ->dequeue it
772 find->m_prev->m_next = find->m_next;
774 *head = find->m_next;
777 find->m_next->m_prev = find->m_prev;
779 *tail = find->m_prev;
781 break; // there can be only one duplicate
785 if (!find) { // did not find a duplicate
786 find = xmalloc(sizeof(struct mod_list_t));
789 find->m_options = opt;
794 (*tail)->m_next = find;
795 find->m_prev = *tail;
805 /* Add all dependable module for that new module */
806 for (i = 0; i < dt->m_depcnt; i++)
807 check_dep(dt->m_deparr[i], head, tail);
811 static int mod_insert(char *mod, int argc, char **argv)
813 struct mod_list_t *tail = 0;
814 struct mod_list_t *head = 0;
817 // get dep list for module mod
818 check_dep(mod, &head, &tail);
823 // append module args
824 for (i = 0; i < argc; i++)
825 head->m_options = append_option(head->m_options, argv[i]);
828 // process tail ---> head
829 if ((rc = mod_process(tail, 1)) != 0) {
831 * In case of using udev, multiple instances of modprobe can be
832 * spawned to load the same module (think of two same usb devices,
833 * for example; or cold-plugging at boot time). Thus we shouldn't
834 * fail if the module was loaded, and not by us.
836 if (already_loaded(mod))
846 static int mod_remove(char *mod)
849 static struct mod_list_t rm_a_dummy = { "-a", NULL, NULL, NULL, NULL };
851 struct mod_list_t *head = 0;
852 struct mod_list_t *tail = 0;
855 check_dep(mod, &head, &tail);
857 head = tail = &rm_a_dummy;
860 rc = mod_process(head, 0); // process head ---> tail
867 int modprobe_main(int argc, char** argv)
869 int rc = EXIT_SUCCESS;
872 opt_complementary = "?V-:q-v:v-q";
873 main_opts = getopt32(argc, argv, "acdklnqrst:vVC:",
875 if (main_opts & (DUMP_CONF_EXIT | LIST_ALL))
877 if (main_opts & (RESTRICT_DIR | CONFIG_FILE))
878 bb_error_msg_and_die("-t and -C not supported");
880 depend = build_dep();
883 bb_error_msg_and_die("cannot parse modules.dep");
887 if (mod_remove(optind < argc ?
888 argv[optind] : NULL)) {
889 bb_error_msg("failed to remove module %s",
893 } while (++optind < argc);
896 bb_error_msg_and_die("no module or pattern provided");
898 if (mod_insert(argv[optind], argc - optind - 1, argv + optind + 1))
899 bb_error_msg_and_die("failed to load module %s", argv[optind]);
902 /* Here would be a good place to free up memory allocated during the dependencies build. */