/* vi: set sw=4 ts=4: */ /* * simplified modprobe * * Copyright (c) 2008 Vladimir Dronnikov * Copyright (c) 2008 Bernhard Reutner-Fischer (initial depmod code) * * Licensed under GPLv2, see file LICENSE in this tarball for details. */ #include "libbb.h" #include <sys/utsname.h> /* uname() */ #include <fnmatch.h> extern int init_module(void *module, unsigned long len, const char *options); extern int delete_module(const char *module, unsigned flags); extern int query_module(const char *name, int which, void *buf, size_t bufsize, size_t *ret); #define dbg1_error_msg(...) ((void)0) #define dbg2_error_msg(...) ((void)0) //#define dbg1_error_msg(...) bb_error_msg(__VA_ARGS__) //#define dbg2_error_msg(...) bb_error_msg(__VA_ARGS__) #define DEPFILE_BB CONFIG_DEFAULT_DEPMOD_FILE".bb" enum { OPT_q = (1 << 0), /* be quiet */ OPT_r = (1 << 1), /* module removal instead of loading */ }; typedef struct module_info { char *pathname; char *aliases; char *deps; } module_info; /* * GLOBALS */ struct globals { module_info *modinfo; char *module_load_options; smallint dep_bb_seen; smallint wrote_dep_bb_ok; int module_count; int module_found_idx; int stringbuf_idx; char stringbuf[32 * 1024]; /* some modules have lots of stuff */ /* for example, drivers/media/video/saa7134/saa7134.ko */ }; #define G (*ptr_to_globals) #define modinfo (G.modinfo ) #define dep_bb_seen (G.dep_bb_seen ) #define wrote_dep_bb_ok (G.wrote_dep_bb_ok ) #define module_count (G.module_count ) #define module_found_idx (G.module_found_idx ) #define module_load_options (G.module_load_options) #define stringbuf_idx (G.stringbuf_idx ) #define stringbuf (G.stringbuf ) #define INIT_G() do { \ SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \ } while (0) static void appendc(char c) { if (stringbuf_idx < sizeof(stringbuf)) stringbuf[stringbuf_idx++] = c; } static void bksp(void) { if (stringbuf_idx) stringbuf_idx--; } static void append(const char *s) { size_t len = strlen(s); if (stringbuf_idx + len < sizeof(stringbuf)) { memcpy(stringbuf + stringbuf_idx, s, len); stringbuf_idx += len; } } static void reset_stringbuf(void) { stringbuf_idx = 0; } static char* copy_stringbuf(void) { char *copy = xmalloc(stringbuf_idx); return memcpy(copy, stringbuf, stringbuf_idx); } static char* find_keyword(char *ptr, size_t len, const char *word) { int wlen; if (!ptr) /* happens if xmalloc_open_zipped_read_close cannot read it */ return NULL; wlen = strlen(word); len -= wlen - 1; while ((ssize_t)len > 0) { char *old = ptr; /* search for the first char in word */ ptr = memchr(ptr, *word, len); if (ptr == NULL) /* no occurance left, done */ break; if (strncmp(ptr, word, wlen) == 0) return ptr + wlen; /* found, return ptr past it */ ++ptr; len -= (ptr - old); } return NULL; } static void replace(char *s, char what, char with) { while (*s) { if (what == *s) *s = with; ++s; } } /* Take "word word", return malloced "word",NUL,"word",NUL,NUL */ static char* str_2_list(const char *str) { int len = strlen(str) + 1; char *dst = xmalloc(len + 1); dst[len] = '\0'; memcpy(dst, str, len); //TODO: protect against 2+ spaces: "word word" replace(dst, ' ', '\0'); return dst; } /* We use error numbers in a loose translation... */ static const char *moderror(int err) { switch (err) { case ENOEXEC: return "invalid module format"; case ENOENT: return "unknown symbol in module or invalid parameter"; case ESRCH: return "module has wrong symbol version"; case EINVAL: /* "invalid parameter" */ return "unknown symbol in module or invalid parameter" + sizeof("unknown symbol in module or"); default: return strerror(err); } } static int load_module(const char *fname, const char *options) { #if 1 int r; size_t len = MAXINT(ssize_t); char *module_image; dbg1_error_msg("load_module('%s','%s')", fname, options); module_image = xmalloc_open_zipped_read_close(fname, &len); r = (!module_image || init_module(module_image, len, options ? options : "") != 0); free(module_image); dbg1_error_msg("load_module:%d", r); return r; /* 0 = success */ #else /* For testing */ dbg1_error_msg("load_module('%s','%s')", fname, options); return 1; #endif } static void parse_module(module_info *info, const char *pathname) { char *module_image; char *ptr; size_t len; size_t pos; dbg1_error_msg("parse_module('%s')", pathname); /* Read (possibly compressed) module */ len = 64 * 1024 * 1024; /* 64 Mb at most */ module_image = xmalloc_open_zipped_read_close(pathname, &len); //TODO: optimize redundant module body reads /* "alias1 symbol:sym1 alias2 symbol:sym2" */ reset_stringbuf(); pos = 0; while (1) { ptr = find_keyword(module_image + pos, len - pos, "alias="); if (!ptr) { ptr = find_keyword(module_image + pos, len - pos, "__ksymtab_"); if (!ptr) break; /* DOCME: __ksymtab_gpl and __ksymtab_strings occur * in many modules. What do they mean? */ if (strcmp(ptr, "gpl") == 0 || strcmp(ptr, "strings") == 0) goto skip; dbg2_error_msg("alias:'symbol:%s'", ptr); append("symbol:"); } else { dbg2_error_msg("alias:'%s'", ptr); } append(ptr); appendc(' '); skip: pos = (ptr - module_image); } bksp(); /* remove last ' ' */ appendc('\0'); info->aliases = copy_stringbuf(); /* "dependency1 depandency2" */ reset_stringbuf(); ptr = find_keyword(module_image, len, "depends="); if (ptr && *ptr) { replace(ptr, ',', ' '); replace(ptr, '-', '_'); dbg2_error_msg("dep:'%s'", ptr); append(ptr); } appendc('\0'); info->deps = copy_stringbuf(); free(module_image); } static int pathname_matches_modname(const char *pathname, const char *modname) { const char *fname = bb_get_last_path_component_nostrip(pathname); const char *suffix = strrstr(fname, ".ko"); //TODO: can do without malloc? char *name = xstrndup(fname, suffix - fname); int r; replace(name, '-', '_'); r = (strcmp(name, modname) == 0); free(name); return r; } static FAST_FUNC int fileAction(const char *pathname, struct stat *sb UNUSED_PARAM, void *modname_to_match, int depth UNUSED_PARAM) { int cur; const char *fname; pathname += 2; /* skip "./" */ fname = bb_get_last_path_component_nostrip(pathname); if (!strrstr(fname, ".ko")) { dbg1_error_msg("'%s' is not a module", pathname); return TRUE; /* not a module, continue search */ } cur = module_count++; modinfo = xrealloc_vector(modinfo, 12, cur); modinfo[cur].pathname = xstrdup(pathname); /*modinfo[cur].aliases = NULL; - xrealloc_vector did it */ /*modinfo[cur+1].pathname = NULL;*/ if (!pathname_matches_modname(fname, modname_to_match)) { dbg1_error_msg("'%s' module name doesn't match", pathname); return TRUE; /* module name doesn't match, continue search */ } dbg1_error_msg("'%s' module name matches", pathname); module_found_idx = cur; parse_module(&modinfo[cur], pathname); if (!(option_mask32 & OPT_r)) { if (load_module(pathname, module_load_options) == 0) { /* Load was successful, there is nothing else to do. * This can happen ONLY for "top-level" module load, * not a dep, because deps dont do dirscan. */ exit(EXIT_SUCCESS); } } return TRUE; } static int load_dep_bb(void) { char *line; FILE *fp = fopen_for_read(DEPFILE_BB); if (!fp) return 0; dep_bb_seen = 1; dbg1_error_msg("loading "DEPFILE_BB); /* Why? There is a rare scenario: we did not find modprobe.dep.bb, * we scanned the dir and found no module by name, then we search * for alias (full scan), and we decided to generate modprobe.dep.bb. * But we see modprobe.dep.bb.new! Other modprobe is at work! * We wait and other modprobe renames it to modprobe.dep.bb. * Now we can use it. * But we already have modinfo[] filled, and "module_count = 0" * makes us start anew. Yes, we leak modinfo[].xxx pointers - * there is not much of data there anyway. */ module_count = 0; memset(&modinfo[0], 0, sizeof(modinfo[0])); while ((line = xmalloc_fgetline(fp)) != NULL) { char* space; int cur; if (!line[0]) { free(line); continue; } space = strchrnul(line, ' '); cur = module_count++; modinfo = xrealloc_vector(modinfo, 12, cur); /*modinfo[cur+1].pathname = NULL; - xrealloc_vector did it */ modinfo[cur].pathname = line; /* we take ownership of malloced block here */ if (*space) *space++ = '\0'; modinfo[cur].aliases = space; modinfo[cur].deps = xmalloc_fgetline(fp) ? : xzalloc(1); if (modinfo[cur].deps[0]) { /* deps are not "", so next line must be empty */ line = xmalloc_fgetline(fp); /* Refuse to work with damaged config file */ if (line && line[0]) bb_error_msg_and_die("error in %s at '%s'", DEPFILE_BB, line); free(line); } } return 1; } static int start_dep_bb_writeout(void) { int fd; /* depmod -n: write result to stdout */ if (applet_name[0] == 'd' && (option_mask32 & 1)) return STDOUT_FILENO; fd = open(DEPFILE_BB".new", O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, 0644); if (fd < 0) { if (errno == EEXIST) { int count = 5 * 20; dbg1_error_msg(DEPFILE_BB".new exists, waiting for "DEPFILE_BB); while (1) { usleep(1000*1000 / 20); if (load_dep_bb()) { dbg1_error_msg(DEPFILE_BB" appeared"); return -2; /* magic number */ } if (!--count) break; } bb_error_msg("deleting stale %s", DEPFILE_BB".new"); fd = open_or_warn(DEPFILE_BB".new", O_WRONLY | O_CREAT | O_TRUNC); } } dbg1_error_msg("opened "DEPFILE_BB".new:%d", fd); return fd; } static void write_out_dep_bb(int fd) { int i; FILE *fp; /* We want good error reporting. fdprintf is not good enough. */ fp = fdopen(fd, "w"); if (!fp) { close(fd); goto err; } i = 0; while (modinfo[i].pathname) { fprintf(fp, "%s%s%s\n" "%s%s\n", modinfo[i].pathname, modinfo[i].aliases[0] ? " " : "", modinfo[i].aliases, modinfo[i].deps, modinfo[i].deps[0] ? "\n" : ""); i++; } /* Badly formatted depfile is a no-no. Be paranoid. */ errno = 0; if (ferror(fp) | fclose(fp)) /* | instead of || is intended */ goto err; if (fd == STDOUT_FILENO) /* it was depmod -n */ goto ok; if (rename(DEPFILE_BB".new", DEPFILE_BB) != 0) { err: bb_perror_msg("can't create %s", DEPFILE_BB); unlink(DEPFILE_BB".new"); } else { ok: wrote_dep_bb_ok = 1; dbg1_error_msg("created "DEPFILE_BB); } } static module_info* find_alias(const char *alias) { int i; int dep_bb_fd; module_info *result; dbg1_error_msg("find_alias('%s')", alias); try_again: /* First try to find by name (cheaper) */ i = 0; while (modinfo[i].pathname) { if (pathname_matches_modname(modinfo[i].pathname, alias)) { dbg1_error_msg("found '%s' in module '%s'", alias, modinfo[i].pathname); if (!modinfo[i].aliases) { parse_module(&modinfo[i], modinfo[i].pathname); } return &modinfo[i]; } i++; } /* Ok, we definitely have to scan module bodies. This is a good * moment to generate modprobe.dep.bb, if it does not exist yet */ dep_bb_fd = dep_bb_seen ? -1 : start_dep_bb_writeout(); if (dep_bb_fd == -2) /* modprobe.dep.bb appeared? */ goto try_again; /* Scan all module bodies, extract modinfo (it contains aliases) */ i = 0; result = NULL; while (modinfo[i].pathname) { char *desc, *s; if (!modinfo[i].aliases) { parse_module(&modinfo[i], modinfo[i].pathname); } if (result) { i++; continue; } /* "alias1 symbol:sym1 alias2 symbol:sym2" */ desc = str_2_list(modinfo[i].aliases); /* Does matching substring exist? */ for (s = desc; *s; s += strlen(s) + 1) { /* Aliases in module bodies can be defined with * shell patterns. Example: * "pci:v000010DEd000000D9sv*sd*bc*sc*i*". * Plain strcmp() won't catch that */ if (fnmatch(s, alias, 0) == 0) { dbg1_error_msg("found alias '%s' in module '%s'", alias, modinfo[i].pathname); result = &modinfo[i]; break; } } free(desc); if (result && dep_bb_fd < 0) return result; i++; } /* Create module.dep.bb if needed */ if (dep_bb_fd >= 0) { write_out_dep_bb(dep_bb_fd); } dbg1_error_msg("find_alias '%s' returns %p", alias, result); return result; } #if ENABLE_FEATURE_MODPROBE_SMALL_CHECK_ALREADY_LOADED // TODO: open only once, invent config_rewind() static int already_loaded(const char *name) { int ret = 0; char *s; parser_t *parser = config_open2("/proc/modules", xfopen_for_read); while (config_read(parser, &s, 1, 1, "# \t", PARSE_NORMAL & ~PARSE_GREEDY)) { if (strcmp(s, name) == 0) { ret = 1; break; } } config_close(parser); return ret; } #else #define already_loaded(name) is_rmmod #endif /* * Given modules definition and module name (or alias, or symbol) * load/remove the module respecting dependencies. * NB: also called by depmod with bogus name "/", * just in order to force modprobe.dep.bb creation. */ #if !ENABLE_FEATURE_MODPROBE_SMALL_OPTIONS_ON_CMDLINE #define process_module(a,b) process_module(a) #define cmdline_options "" #endif static void process_module(char *name, const char *cmdline_options) { char *s, *deps, *options; module_info *info; int is_rmmod = (option_mask32 & OPT_r) != 0; dbg1_error_msg("process_module('%s','%s')", name, cmdline_options); replace(name, '-', '_'); dbg1_error_msg("already_loaded:%d is_rmmod:%d", already_loaded(name), is_rmmod); if (already_loaded(name) != is_rmmod) { dbg1_error_msg("nothing to do for '%s'", name); return; } options = NULL; if (!is_rmmod) { char *opt_filename = xasprintf("/etc/modules/%s", name); options = xmalloc_open_read_close(opt_filename, NULL); if (options) replace(options, '\n', ' '); #if ENABLE_FEATURE_MODPROBE_SMALL_OPTIONS_ON_CMDLINE if (cmdline_options) { /* NB: cmdline_options always have one leading ' ' * (see main()), we remove it here */ char *op = xasprintf(options ? "%s %s" : "%s %s" + 3, cmdline_options + 1, options); free(options); options = op; } #endif free(opt_filename); module_load_options = options; dbg1_error_msg("process_module('%s'): options:'%s'", name, options); } if (!module_count) { /* Scan module directory. This is done only once. * It will attempt module load, and will exit(EXIT_SUCCESS) * on success. */ module_found_idx = -1; recursive_action(".", ACTION_RECURSE, /* flags */ fileAction, /* file action */ NULL, /* dir action */ name, /* user data */ 0); /* depth */ dbg1_error_msg("dirscan complete"); /* Module was not found, or load failed, or is_rmmod */ if (module_found_idx >= 0) { /* module was found */ info = &modinfo[module_found_idx]; } else { /* search for alias, not a plain module name */ info = find_alias(name); } } else { info = find_alias(name); } /* rmmod? unload it by name */ if (is_rmmod) { if (delete_module(name, O_NONBLOCK | O_EXCL) != 0 && !(option_mask32 & OPT_q) ) { bb_perror_msg("remove '%s'", name); goto ret; } /* N.B. we do not stop here - * continue to unload modules on which the module depends: * "-r --remove: option causes modprobe to remove a module. * If the modules it depends on are also unused, modprobe * will try to remove them, too." */ } if (!info) { /* both dirscan and find_alias found nothing */ if (applet_name[0] != 'd') /* it wasn't depmod */ bb_error_msg("module '%s' not found", name); //TODO: _and_die()? goto ret; } /* Iterate thru dependencies, trying to (un)load them */ deps = str_2_list(info->deps); for (s = deps; *s; s += strlen(s) + 1) { //if (strcmp(name, s) != 0) // N.B. do loops exist? dbg1_error_msg("recurse on dep '%s'", s); process_module(s, NULL); dbg1_error_msg("recurse on dep '%s' done", s); } free(deps); /* modprobe -> load it */ if (!is_rmmod) { if (!options || strstr(options, "blacklist") == NULL) { errno = 0; if (load_module(info->pathname, options) != 0) { if (EEXIST != errno) { bb_error_msg("'%s': %s", info->pathname, moderror(errno)); } else { dbg1_error_msg("'%s': %s", info->pathname, moderror(errno)); } } } else { dbg1_error_msg("'%s': blacklisted", info->pathname); } } ret: free(options); //TODO: return load attempt result from process_module. //If dep didn't load ok, continuing makes little sense. } #undef cmdline_options /* For reference, module-init-tools v3.4 options: # insmod Usage: insmod filename [args] # rmmod --help Usage: rmmod [-fhswvV] modulename ... -f (or --force) forces a module unload, and may crash your machine. This requires the Forced Module Removal option when the kernel was compiled. -h (or --help) prints this help text -s (or --syslog) says use syslog, not stderr -v (or --verbose) enables more messages -V (or --version) prints the version code -w (or --wait) begins module removal even if it is used and will stop new users from accessing the module (so it should eventually fall to zero). # modprobe Usage: modprobe [-v] [-V] [-C config-file] [-n] [-i] [-q] [-b] [-o <modname>] [ --dump-modversions ] <modname> [parameters...] modprobe -r [-n] [-i] [-v] <modulename> ... modprobe -l -t <dirname> [ -a <modulename> ...] # depmod --help depmod 3.4 -- part of module-init-tools depmod -[aA] [-n -e -v -q -V -r -u] [-b basedirectory] [forced_version] depmod [-n -e -v -q -r -u] [-F kernelsyms] module1.ko module2.ko ... If no arguments (except options) are given, "depmod -a" is assumed. depmod will output a dependency list suitable for the modprobe utility. Options: -a, --all Probe all modules -A, --quick Only does the work if there's a new module -n, --show Write the dependency file on stdout only -e, --errsyms Report not supplied symbols -V, --version Print the release version -v, --verbose Enable verbose mode -h, --help Print this usage message The following options are useful for people managing distributions: -b basedirectory --basedir basedirectory Use an image of a module tree -F kernelsyms --filesyms kernelsyms Use the file instead of the current kernel symbols */ int modprobe_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int modprobe_main(int argc UNUSED_PARAM, char **argv) { struct utsname uts; char applet0 = applet_name[0]; IF_FEATURE_MODPROBE_SMALL_OPTIONS_ON_CMDLINE(char *options;) /* are we lsmod? -> just dump /proc/modules */ if ('l' == applet0) { xprint_and_close_file(xfopen_for_read("/proc/modules")); return EXIT_SUCCESS; } INIT_G(); /* Prevent ugly corner cases with no modules at all */ modinfo = xzalloc(sizeof(modinfo[0])); if ('i' != applet0) { /* not insmod */ /* Goto modules directory */ xchdir(CONFIG_DEFAULT_MODULES_DIR); } uname(&uts); /* never fails */ /* depmod? */ if ('d' == applet0) { /* Supported: * -n: print result to stdout * -a: process all modules (default) * optional VERSION parameter * Ignored: * -A: do work only if a module is newer than depfile * -e: report any symbols which a module needs * which are not supplied by other modules or the kernel * -F FILE: System.map (symbols for -e) * -q, -r, -u: noop? * Not supported: * -b BASEDIR: (TODO!) modules are in * $BASEDIR/lib/modules/$VERSION * -v: human readable deps to stdout * -V: version (don't want to support it - people may depend * on it as an indicator of "standard" depmod) * -h: help (well duh) * module1.o module2.o parameters (just ignored for now) */ getopt32(argv, "na" "AeF:qru" /* "b:vV", NULL */, NULL); argv += optind; /* if (argv[0] && argv[1]) bb_show_usage(); */ /* Goto $VERSION directory */ xchdir(argv[0] ? argv[0] : uts.release); /* Force full module scan by asking to find a bogus module. * This will generate modules.dep.bb as a side effect. */ process_module((char*)"/", NULL); return !wrote_dep_bb_ok; } /* insmod, modprobe, rmmod require at least one argument */ opt_complementary = "-1"; /* only -q (quiet) and -r (rmmod), * the rest are accepted and ignored (compat) */ getopt32(argv, "qrfsvw"); argv += optind; /* are we rmmod? -> simulate modprobe -r */ if ('r' == applet0) { option_mask32 |= OPT_r; } if ('i' != applet0) { /* not insmod */ /* Goto $VERSION directory */ xchdir(uts.release); } #if ENABLE_FEATURE_MODPROBE_SMALL_OPTIONS_ON_CMDLINE /* If not rmmod, parse possible module options given on command line. * insmod/modprobe takes one module name, the rest are parameters. */ options = NULL; if ('r' != applet0) { char **arg = argv; while (*++arg) { /* Enclose options in quotes */ char *s = options; options = xasprintf("%s \"%s\"", s ? s : "", *arg); free(s); *arg = NULL; } } #else if ('r' != applet0) argv[1] = NULL; #endif if ('i' == applet0) { /* insmod */ size_t len; void *map; len = MAXINT(ssize_t); map = xmalloc_xopen_read_close(*argv, &len); if (init_module(map, len, IF_FEATURE_MODPROBE_SMALL_OPTIONS_ON_CMDLINE(options ? options : "") IF_NOT_FEATURE_MODPROBE_SMALL_OPTIONS_ON_CMDLINE("") ) != 0) bb_error_msg_and_die("can't insert '%s': %s", *argv, moderror(errno)); return 0; } /* Try to load modprobe.dep.bb */ load_dep_bb(); /* Load/remove modules. * Only rmmod loops here, modprobe has only argv[0] */ do { process_module(*argv++, options); } while (*argv); if (ENABLE_FEATURE_CLEAN_UP) { IF_FEATURE_MODPROBE_SMALL_OPTIONS_ON_CMDLINE(free(options);) } return EXIT_SUCCESS; }