busybox/modutils/modprobe.c

/* vi: set sw=4 ts=4: */
/*
 * Modprobe written from scratch for BusyBox
 *
 * Copyright (c) 2008 Timo Teras <timo.teras@iki.fi>
 * Copyright (c) 2008 Vladimir Dronnikov
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 */

/* Note that unlike older versions of modules.dep/depmod (busybox and m-i-t),
 * we expect the full dependency list to be specified in modules.dep.
 * Older versions would only export the direct dependency list.
 */
#include "libbb.h"
#include "modutils.h"
#include <sys/utsname.h>
#include <fnmatch.h>

//#define DBG(fmt, ...) bb_error_msg("%s: " fmt, __func__, ## __VA_ARGS__)
#define DBG(...) ((void)0)

//usage:#if !ENABLE_MODPROBE_SMALL
//usage:#define modprobe_notes_usage
//usage:	"modprobe can (un)load a stack of modules, passing each module options (when\n"
//usage:	"loading). modprobe uses a configuration file to determine what option(s) to\n"
//usage:	"pass each module it loads.\n"
//usage:	"\n"
//usage:	"The configuration file is searched (in this order):\n"
//usage:	"\n"
//usage:	"    /etc/modprobe.conf (2.6 only)\n"
//usage:	"    /etc/modules.conf\n"
//usage:	"    /etc/conf.modules (deprecated)\n"
//usage:	"\n"
//usage:	"They all have the same syntax (see below). If none is present, it is\n"
//usage:	"_not_ an error; each loaded module is then expected to load without\n"
//usage:	"options. Once a file is found, the others are tested for.\n"
//usage:	"\n"
//usage:	"/etc/modules.conf entry format:\n"
//usage:	"\n"
//usage:	"  alias <alias_name> <mod_name>\n"
//usage:	"    Makes it possible to modprobe alias_name, when there is no such module.\n"
//usage:	"    It makes sense if your mod_name is long, or you want a more representative\n"
//usage:	"    name for that module (eg. 'scsi' in place of 'aha7xxx').\n"
//usage:	"    This makes it also possible to use a different set of options (below) for\n"
//usage:	"    the module and the alias.\n"
//usage:	"    A module can be aliased more than once.\n"
//usage:	"\n"
//usage:	"  options <mod_name|alias_name> <symbol=value...>\n"
//usage:	"    When loading module mod_name (or the module aliased by alias_name), pass\n"
//usage:	"    the \"symbol=value\" pairs as option to that module.\n"
//usage:	"\n"
//usage:	"Sample /etc/modules.conf file:\n"
//usage:	"\n"
//usage:	"  options tulip irq=3\n"
//usage:	"  alias tulip tulip2\n"
//usage:	"  options tulip2 irq=4 io=0x308\n"
//usage:	"\n"
//usage:	"Other functionality offered by 'classic' modprobe is not available in\n"
//usage:	"this implementation.\n"
//usage:	"\n"
//usage:	"If module options are present both in the config file, and on the command line,\n"
//usage:	"then the options from the command line will be passed to the module _after_\n"
//usage:	"the options from the config file. That way, you can have defaults in the config\n"
//usage:	"file, and override them for a specific usage from the command line.\n"
//usage:#define modprobe_example_usage
//usage:       "(with the above /etc/modules.conf):\n\n"
//usage:       "$ modprobe tulip\n"
//usage:       "   will load the module 'tulip' with default option 'irq=3'\n\n"
//usage:       "$ modprobe tulip irq=5\n"
//usage:       "   will load the module 'tulip' with option 'irq=5', thus overriding the default\n\n"
//usage:       "$ modprobe tulip2\n"
//usage:       "   will load the module 'tulip' with default options 'irq=4 io=0x308',\n"
//usage:       "   which are the default for alias 'tulip2'\n\n"
//usage:       "$ modprobe tulip2 irq=8\n"
//usage:       "   will load the module 'tulip' with default options 'irq=4 io=0x308 irq=8',\n"
//usage:       "   which are the default for alias 'tulip2' overridden by the option 'irq=8'\n\n"
//usage:       "   from the command line\n\n"
//usage:       "$ modprobe tulip2 irq=2 io=0x210\n"
//usage:       "   will load the module 'tulip' with default options 'irq=4 io=0x308 irq=4 io=0x210',\n"
//usage:       "   which are the default for alias 'tulip2' overridden by the options 'irq=2 io=0x210'\n\n"
//usage:       "   from the command line\n"
//usage:
//usage:#define modprobe_trivial_usage
//usage:	"[-alrqvs"
//usage:	IF_FEATURE_MODPROBE_BLACKLIST("b")
//usage:	"] MODULE [symbol=value]..."
//usage:#define modprobe_full_usage "\n\n"
//usage:       "Options:"
//usage:     "\n	-a	Load multiple MODULEs"
//usage:     "\n	-l	List (MODULE is a pattern)"
//usage:     "\n	-r	Remove MODULE (stacks) or do autoclean"
//usage:     "\n	-q	Quiet"
//usage:     "\n	-v	Verbose"
//usage:     "\n	-s	Log to syslog"
//usage:	IF_FEATURE_MODPROBE_BLACKLIST(
//usage:     "\n	-b	Apply blacklist to module names too"
//usage:	)
//usage:#endif /* !ENABLE_MODPROBE_SMALL */

/* Note that usage text doesn't document various 2.4 options
 * we pull in through INSMOD_OPTS define */

#define MODPROBE_COMPLEMENTARY "q-v:v-q:l--ar:a--lr:r--al"
#define MODPROBE_OPTS  "alr" IF_FEATURE_MODPROBE_BLACKLIST("b")
//#define MODPROBE_COMPLEMENTARY "q-v:v-q:l--acr:a--lr:r--al"
//#define MODPROBE_OPTS  "acd:lnrt:C:" IF_FEATURE_MODPROBE_BLACKLIST("b")
enum {
	MODPROBE_OPT_INSERT_ALL = (INSMOD_OPT_UNUSED << 0), /* a */
	//MODPROBE_OPT_DUMP_ONLY= (INSMOD_OPT_UNUSED << x), /* c */
	//MODPROBE_OPT_DIRNAME  = (INSMOD_OPT_UNUSED << x), /* d */
	MODPROBE_OPT_LIST_ONLY  = (INSMOD_OPT_UNUSED << 1), /* l */
	//MODPROBE_OPT_SHOW_ONLY= (INSMOD_OPT_UNUSED << x), /* n */
	MODPROBE_OPT_REMOVE     = (INSMOD_OPT_UNUSED << 2), /* r */
	//MODPROBE_OPT_RESTRICT = (INSMOD_OPT_UNUSED << x), /* t */
	//MODPROBE_OPT_VERONLY  = (INSMOD_OPT_UNUSED << x), /* V */
	//MODPROBE_OPT_CONFIGFILE=(INSMOD_OPT_UNUSED << x), /* C */
	MODPROBE_OPT_BLACKLIST  = (INSMOD_OPT_UNUSED << 3) * ENABLE_FEATURE_MODPROBE_BLACKLIST,
};

#define MODULE_FLAG_LOADED              0x0001
#define MODULE_FLAG_NEED_DEPS           0x0002
/* "was seen in modules.dep": */
#define MODULE_FLAG_FOUND_IN_MODDEP     0x0004
#define MODULE_FLAG_BLACKLISTED         0x0008

struct module_entry { /* I'll call it ME. */
	unsigned flags;
	char *modname; /* stripped of /path/, .ext and s/-/_/g */
	const char *probed_name; /* verbatim as seen on cmdline */
	char *options; /* options from config files */
	llist_t *realnames; /* strings. if this module is an alias, */
	/* real module name is one of these. */
//Can there really be more than one? Example from real kernel?
	llist_t *deps; /* strings. modules we depend on */
};

struct globals {
	llist_t *db; /* MEs of all modules ever seen (caching for speed) */
	llist_t *probes; /* MEs of module(s) requested on cmdline */
	char *cmdline_mopts; /* module options from cmdline */
	int num_unresolved_deps;
	/* bool. "Did we have 'symbol:FOO' requested on cmdline?" */
	smallint need_symbols;
} FIX_ALIASING;
#define G (*(struct globals*)&bb_common_bufsiz1)
#define INIT_G() do { } while (0)


static int read_config(const char *path);

static char *gather_options_str(char *opts, const char *append)
{
	/* Speed-optimized. We call gather_options_str many times. */
	if (append) {
		if (opts == NULL) {
			opts = xstrdup(append);
		} else {
			int optlen = strlen(opts);
			opts = xrealloc(opts, optlen + strlen(append) + 2);
			sprintf(opts + optlen, " %s", append);
		}
	}
	return opts;
}

static struct module_entry *helper_get_module(const char *module, int create)
{
	char modname[MODULE_NAME_LEN];
	struct module_entry *e;
	llist_t *l;

	filename2modname(module, modname);
	for (l = G.db; l != NULL; l = l->link) {
		e = (struct module_entry *) l->data;
		if (strcmp(e->modname, modname) == 0)
			return e;
	}
	if (!create)
		return NULL;

	e = xzalloc(sizeof(*e));
	e->modname = xstrdup(modname);
	llist_add_to(&G.db, e);

	return e;
}
static struct module_entry *get_or_add_modentry(const char *module)
{
	return helper_get_module(module, 1);
}
static struct module_entry *get_modentry(const char *module)
{
	return helper_get_module(module, 0);
}

static void add_probe(const char *name)
{
	struct module_entry *m;

	m = get_or_add_modentry(name);
	if (!(option_mask32 & MODPROBE_OPT_REMOVE)
	 && (m->flags & MODULE_FLAG_LOADED)
	) {
		DBG("skipping %s, it is already loaded", name);
		return;
	}

	DBG("queuing %s", name);
	m->probed_name = name;
	m->flags |= MODULE_FLAG_NEED_DEPS;
	llist_add_to_end(&G.probes, m);
	G.num_unresolved_deps++;
	if (ENABLE_FEATURE_MODUTILS_SYMBOLS
	 && strncmp(m->modname, "symbol:", 7) == 0
	) {
		G.need_symbols = 1;
	}
}

static int FAST_FUNC config_file_action(const char *filename,
					struct stat *statbuf UNUSED_PARAM,
					void *userdata UNUSED_PARAM,
					int depth UNUSED_PARAM)
{
	char *tokens[3];
	parser_t *p;
	struct module_entry *m;
	int rc = TRUE;

	if (bb_basename(filename)[0] == '.')
		goto error;

	p = config_open2(filename, fopen_for_read);
	if (p == NULL) {
		rc = FALSE;
		goto error;
	}

	while (config_read(p, tokens, 3, 2, "# \t", PARSE_NORMAL)) {
//Use index_in_strings?
		if (strcmp(tokens[0], "alias") == 0) {
			/* alias <wildcard> <modulename> */
			llist_t *l;
			char wildcard[MODULE_NAME_LEN];
			char *rmod;

			if (tokens[2] == NULL)
				continue;
			filename2modname(tokens[1], wildcard);

			for (l = G.probes; l != NULL; l = l->link) {
				m = (struct module_entry *) l->data;
				if (fnmatch(wildcard, m->modname, 0) != 0)
					continue;
				rmod = filename2modname(tokens[2], NULL);
				llist_add_to(&m->realnames, rmod);

				if (m->flags & MODULE_FLAG_NEED_DEPS) {
					m->flags &= ~MODULE_FLAG_NEED_DEPS;
					G.num_unresolved_deps--;
				}

				m = get_or_add_modentry(rmod);
				if (!(m->flags & MODULE_FLAG_NEED_DEPS)) {
					m->flags |= MODULE_FLAG_NEED_DEPS;
					G.num_unresolved_deps++;
				}
			}
		} else if (strcmp(tokens[0], "options") == 0) {
			/* options <modulename> <option...> */
			if (tokens[2] == NULL)
				continue;
			m = get_or_add_modentry(tokens[1]);
			m->options = gather_options_str(m->options, tokens[2]);
		} else if (strcmp(tokens[0], "include") == 0) {
			/* include <filename> */
			read_config(tokens[1]);
		} else if (ENABLE_FEATURE_MODPROBE_BLACKLIST
		 && strcmp(tokens[0], "blacklist") == 0
		) {
			/* blacklist <modulename> */
			get_or_add_modentry(tokens[1])->flags |= MODULE_FLAG_BLACKLISTED;
		}
	}
	config_close(p);
 error:
	return rc;
}

static int read_config(const char *path)
{
	return recursive_action(path, ACTION_RECURSE | ACTION_QUIET,
				config_file_action, NULL, NULL, 1);
}

static const char *humanly_readable_name(struct module_entry *m)
{
	/* probed_name may be NULL. modname always exists. */
	return m->probed_name ? m->probed_name : m->modname;
}

static char *parse_and_add_kcmdline_module_options(char *options, const char *modulename)
{
	char *kcmdline_buf;
	char *kcmdline;
	char *kptr;
	int len;

	kcmdline_buf = xmalloc_open_read_close("/proc/cmdline", NULL);
	if (!kcmdline_buf)
		return options;

	kcmdline = kcmdline_buf;
	len = strlen(modulename);
	while ((kptr = strsep(&kcmdline, "\n\t ")) != NULL) {
		if (strncmp(modulename, kptr, len) != 0)
			continue;
		kptr += len;
		if (*kptr != '.')
			continue;
		/* It is "modulename.xxxx" */
		kptr++;
		if (strchr(kptr, '=') != NULL) {
			/* It is "modulename.opt=[val]" */
			options = gather_options_str(options, kptr);
		}
	}
	free(kcmdline_buf);

	return options;
}

/* Return: similar to bb_init_module:
 * 0 on success,
 * -errno on open/read error,
 * errno on init_module() error
 */
/* NB: INSMOD_OPT_SILENT bit suppresses ONLY non-existent modules,
 * not deleted ones (those are still listed in modules.dep).
 * module-init-tools version 3.4:
 * # modprobe bogus
 * FATAL: Module bogus not found. [exitcode 1]
 * # modprobe -q bogus            [silent, exitcode still 1]
 * but:
 * # rm kernel/drivers/net/dummy.ko
 * # modprobe -q dummy
 * FATAL: Could not open '/lib/modules/xxx/kernel/drivers/net/dummy.ko': No such file or directory
 * [exitcode 1]
 */
static int do_modprobe(struct module_entry *m)
{
	struct module_entry *m2 = m2; /* for compiler */
	char *fn, *options;
	int rc, first;
	llist_t *l;

	if (!(m->flags & MODULE_FLAG_FOUND_IN_MODDEP)) {
		if (!(option_mask32 & INSMOD_OPT_SILENT))
			bb_error_msg("module %s not found in modules.dep",
				humanly_readable_name(m));
		return -ENOENT;
	}
	DBG("do_modprob'ing %s", m->modname);

	if (!(option_mask32 & MODPROBE_OPT_REMOVE))
		m->deps = llist_rev(m->deps);

	for (l = m->deps; l != NULL; l = l->link)
		DBG("dep: %s", l->data);

	first = 1;
	rc = 0;
	while (m->deps) {
		rc = 0;
		fn = llist_pop(&m->deps); /* we leak it */
		m2 = get_or_add_modentry(fn);

		if (option_mask32 & MODPROBE_OPT_REMOVE) {
			/* modprobe -r */
			if (m2->flags & MODULE_FLAG_LOADED) {
				rc = bb_delete_module(m2->modname, O_EXCL);
				if (rc) {
					if (first) {
						bb_error_msg("can't unload module %s: %s",
							humanly_readable_name(m2),
							moderror(rc));
						break;
					}
				} else {
					m2->flags &= ~MODULE_FLAG_LOADED;
				}
			}
			/* do not error out if *deps* fail to unload */
			first = 0;
			continue;
		}

		if (m2->flags & MODULE_FLAG_LOADED) {
			DBG("%s is already loaded, skipping", fn);
			continue;
		}

		options = m2->options;
		m2->options = NULL;
		options = parse_and_add_kcmdline_module_options(options, m2->modname);
		if (m == m2)
			options = gather_options_str(options, G.cmdline_mopts);
		rc = bb_init_module(fn, options);
		DBG("loaded %s '%s', rc:%d", fn, options, rc);
		if (rc == EEXIST)
			rc = 0;
		free(options);
		if (rc) {
			bb_error_msg("can't load module %s (%s): %s",
				humanly_readable_name(m2),
				fn,
				moderror(rc)
			);
			break;
		}
		m2->flags |= MODULE_FLAG_LOADED;
	}

	return rc;
}

static void load_modules_dep(void)
{
	struct module_entry *m;
	char *colon, *tokens[2];
	parser_t *p;

	/* Modprobe does not work at all without modules.dep,
	 * even if the full module name is given. Returning error here
	 * was making us later confuse user with this message:
	 * "module /full/path/to/existing/file/module.ko not found".
	 * It's better to die immediately, with good message.
	 * xfopen_for_read provides that. */
	p = config_open2(CONFIG_DEFAULT_DEPMOD_FILE, xfopen_for_read);

	while (G.num_unresolved_deps
	 && config_read(p, tokens, 2, 1, "# \t", PARSE_NORMAL)
	) {
		colon = last_char_is(tokens[0], ':');
		if (colon == NULL)
			continue;
		*colon = 0;

		m = get_modentry(tokens[0]);
		if (m == NULL)
			continue;

		/* Optimization... */
		if ((m->flags & MODULE_FLAG_LOADED)
		 && !(option_mask32 & MODPROBE_OPT_REMOVE)
		) {
			DBG("skip deps of %s, it's already loaded", tokens[0]);
			continue;
		}

		m->flags |= MODULE_FLAG_FOUND_IN_MODDEP;
		if ((m->flags & MODULE_FLAG_NEED_DEPS) && (m->deps == NULL)) {
			G.num_unresolved_deps--;
			llist_add_to(&m->deps, xstrdup(tokens[0]));
			if (tokens[1])
				string_to_llist(tokens[1], &m->deps, " \t");
		} else
			DBG("skipping dep line");
	}
	config_close(p);
}

int modprobe_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int modprobe_main(int argc UNUSED_PARAM, char **argv)
{
	struct utsname uts;
	int rc;
	unsigned opt;
	struct module_entry *me;

	opt_complementary = MODPROBE_COMPLEMENTARY;
	opt = getopt32(argv, INSMOD_OPTS MODPROBE_OPTS INSMOD_ARGS);
	argv += optind;

	/* Goto modules location */
	xchdir(CONFIG_DEFAULT_MODULES_DIR);
	uname(&uts);
	xchdir(uts.release);

	if (opt & MODPROBE_OPT_LIST_ONLY) {
		char name[MODULE_NAME_LEN];
		char *colon, *tokens[2];
		parser_t *p = config_open2(CONFIG_DEFAULT_DEPMOD_FILE, xfopen_for_read);

		while (config_read(p, tokens, 2, 1, "# \t", PARSE_NORMAL)) {
			colon = last_char_is(tokens[0], ':');
			if (!colon)
				continue;
			*colon = '\0';
			filename2modname(tokens[0], name);
			if (!argv[0])
				puts(tokens[0]);
			else {
				int i;
				for (i = 0; argv[i]; i++) {
					if (fnmatch(argv[i], name, 0) == 0) {
						puts(tokens[0]);
					}
				}
			}
		}
		return EXIT_SUCCESS;
	}

	/* Yes, for some reason -l ignores -s... */
	if (opt & INSMOD_OPT_SYSLOG)
		logmode = LOGMODE_SYSLOG;

	if (!argv[0]) {
		if (opt & MODPROBE_OPT_REMOVE) {
			/* "modprobe -r" (w/o params).
			 * "If name is NULL, all unused modules marked
			 * autoclean will be removed".
			 */
			if (bb_delete_module(NULL, O_NONBLOCK | O_EXCL) != 0)
				bb_perror_msg_and_die("rmmod");
		}
		return EXIT_SUCCESS;
	}

	/* Retrieve module names of already loaded modules */
	{
		char *s;
		parser_t *parser = config_open2("/proc/modules", fopen_for_read);
		while (config_read(parser, &s, 1, 1, "# \t", PARSE_NORMAL & ~PARSE_GREEDY))
			get_or_add_modentry(s)->flags |= MODULE_FLAG_LOADED;
		config_close(parser);
	}

	if (opt & (MODPROBE_OPT_INSERT_ALL | MODPROBE_OPT_REMOVE)) {
		/* Each argument is a module name */
		do {
			DBG("adding module %s", *argv);
			add_probe(*argv++);
		} while (*argv);
	} else {
		/* First argument is module name, rest are parameters */
		DBG("probing just module %s", *argv);
		add_probe(argv[0]);
		G.cmdline_mopts = parse_cmdline_module_options(argv);
	}

	/* Happens if all requested modules are already loaded */
	if (G.probes == NULL)
		return EXIT_SUCCESS;

	read_config("/etc/modprobe.conf");
	read_config("/etc/modprobe.d");
	if (ENABLE_FEATURE_MODUTILS_SYMBOLS && G.need_symbols)
		read_config("modules.symbols");
	load_modules_dep();
	if (ENABLE_FEATURE_MODUTILS_ALIAS && G.num_unresolved_deps) {
		read_config("modules.alias");
		load_modules_dep();
	}

	rc = 0;
	while ((me = llist_pop(&G.probes)) != NULL) {
		if (me->realnames == NULL) {
			DBG("probing by module name");
			/* This is not an alias. Literal names are blacklisted
			 * only if '-b' is given.
			 */
			if (!(opt & MODPROBE_OPT_BLACKLIST)
			 || !(me->flags & MODULE_FLAG_BLACKLISTED)
			) {
				rc |= do_modprobe(me);
			}
			continue;
		}

		/* Probe all real names for the alias */
		do {
			char *realname = llist_pop(&me->realnames);
			struct module_entry *m2;

			DBG("probing alias %s by realname %s", me->modname, realname);
			m2 = get_or_add_modentry(realname);
			if (!(m2->flags & MODULE_FLAG_BLACKLISTED)
			 && (!(m2->flags & MODULE_FLAG_LOADED)
			    || (opt & MODPROBE_OPT_REMOVE))
			) {
//TODO: we can pass "me" as 2nd param to do_modprobe,
//and make do_modprobe emit more meaningful error messages
//with alias name included, not just module name alias resolves to.
				rc |= do_modprobe(m2);
			}
			free(realname);
		} while (me->realnames != NULL);
	}

	return (rc != 0);
}
1	/* vi: set sw=4 ts=4: */
2	/*
3	* Modprobe written from scratch for BusyBox
4	*
5	* Copyright (c) 2008 Timo Teras <timo.teras@iki.fi>
6	* Copyright (c) 2008 Vladimir Dronnikov
7	*
8	* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
9	*/
10
11	/* Note that unlike older versions of modules.dep/depmod (busybox and m-i-t),
12	* we expect the full dependency list to be specified in modules.dep.
13	* Older versions would only export the direct dependency list.
14	*/
15	#include "libbb.h"
16	#include "modutils.h"
17	#include <sys/utsname.h>
18	#include <fnmatch.h>
19
20	//#define DBG(fmt, ...) bb_error_msg("%s: " fmt, __func__, ## __VA_ARGS__)
21	#define DBG(...) ((void)0)
22
23	//usage:#if !ENABLE_MODPROBE_SMALL
24	//usage:#define modprobe_notes_usage
25	//usage: "modprobe can (un)load a stack of modules, passing each module options (when\n"
26	//usage: "loading). modprobe uses a configuration file to determine what option(s) to\n"
27	//usage: "pass each module it loads.\n"
28	//usage: "\n"
29	//usage: "The configuration file is searched (in this order):\n"
30	//usage: "\n"
31	//usage: " /etc/modprobe.conf (2.6 only)\n"
32	//usage: " /etc/modules.conf\n"
33	//usage: " /etc/conf.modules (deprecated)\n"
34	//usage: "\n"
35	//usage: "They all have the same syntax (see below). If none is present, it is\n"
36	//usage: "_not_ an error; each loaded module is then expected to load without\n"
37	//usage: "options. Once a file is found, the others are tested for.\n"
38	//usage: "\n"
39	//usage: "/etc/modules.conf entry format:\n"
40	//usage: "\n"
41	//usage: " alias <alias_name> <mod_name>\n"
42	//usage: " Makes it possible to modprobe alias_name, when there is no such module.\n"
43	//usage: " It makes sense if your mod_name is long, or you want a more representative\n"
44	//usage: " name for that module (eg. 'scsi' in place of 'aha7xxx').\n"
45	//usage: " This makes it also possible to use a different set of options (below) for\n"
46	//usage: " the module and the alias.\n"
47	//usage: " A module can be aliased more than once.\n"
48	//usage: "\n"
49	//usage: " options <mod_name\|alias_name> <symbol=value...>\n"
50	//usage: " When loading module mod_name (or the module aliased by alias_name), pass\n"
51	//usage: " the \"symbol=value\" pairs as option to that module.\n"
52	//usage: "\n"
53	//usage: "Sample /etc/modules.conf file:\n"
54	//usage: "\n"
55	//usage: " options tulip irq=3\n"
56	//usage: " alias tulip tulip2\n"
57	//usage: " options tulip2 irq=4 io=0x308\n"
58	//usage: "\n"
59	//usage: "Other functionality offered by 'classic' modprobe is not available in\n"
60	//usage: "this implementation.\n"
61	//usage: "\n"
62	//usage: "If module options are present both in the config file, and on the command line,\n"
63	//usage: "then the options from the command line will be passed to the module _after_\n"
64	//usage: "the options from the config file. That way, you can have defaults in the config\n"
65	//usage: "file, and override them for a specific usage from the command line.\n"
66	//usage:#define modprobe_example_usage
67	//usage: "(with the above /etc/modules.conf):\n\n"
68	//usage: "$ modprobe tulip\n"
69	//usage: " will load the module 'tulip' with default option 'irq=3'\n\n"
70	//usage: "$ modprobe tulip irq=5\n"
71	//usage: " will load the module 'tulip' with option 'irq=5', thus overriding the default\n\n"
72	//usage: "$ modprobe tulip2\n"
73	//usage: " will load the module 'tulip' with default options 'irq=4 io=0x308',\n"
74	//usage: " which are the default for alias 'tulip2'\n\n"
75	//usage: "$ modprobe tulip2 irq=8\n"
76	//usage: " will load the module 'tulip' with default options 'irq=4 io=0x308 irq=8',\n"
77	//usage: " which are the default for alias 'tulip2' overridden by the option 'irq=8'\n\n"
78	//usage: " from the command line\n\n"
79	//usage: "$ modprobe tulip2 irq=2 io=0x210\n"
80	//usage: " will load the module 'tulip' with default options 'irq=4 io=0x308 irq=4 io=0x210',\n"
81	//usage: " which are the default for alias 'tulip2' overridden by the options 'irq=2 io=0x210'\n\n"
82	//usage: " from the command line\n"
83	//usage:
84	//usage:#define modprobe_trivial_usage
85	//usage: "[-alrqvs"
86	//usage: IF_FEATURE_MODPROBE_BLACKLIST("b")
87	//usage: "] MODULE [symbol=value]..."
88	//usage:#define modprobe_full_usage "\n\n"
89	//usage: "Options:"
90	//usage: "\n -a Load multiple MODULEs"
91	//usage: "\n -l List (MODULE is a pattern)"
92	//usage: "\n -r Remove MODULE (stacks) or do autoclean"
93	//usage: "\n -q Quiet"
94	//usage: "\n -v Verbose"
95	//usage: "\n -s Log to syslog"
96	//usage: IF_FEATURE_MODPROBE_BLACKLIST(
97	//usage: "\n -b Apply blacklist to module names too"
98	//usage: )
99	//usage:#endif /* !ENABLE_MODPROBE_SMALL */
100
101	/* Note that usage text doesn't document various 2.4 options
102	* we pull in through INSMOD_OPTS define */
103
104	#define MODPROBE_COMPLEMENTARY "q-v:v-q:l--ar:a--lr:r--al"
105	#define MODPROBE_OPTS "alr" IF_FEATURE_MODPROBE_BLACKLIST("b")
106	//#define MODPROBE_COMPLEMENTARY "q-v:v-q:l--acr:a--lr:r--al"
107	//#define MODPROBE_OPTS "acd:lnrt:C:" IF_FEATURE_MODPROBE_BLACKLIST("b")
108	enum {
109	MODPROBE_OPT_INSERT_ALL = (INSMOD_OPT_UNUSED << 0), /* a */
110	//MODPROBE_OPT_DUMP_ONLY= (INSMOD_OPT_UNUSED << x), /* c */
111	//MODPROBE_OPT_DIRNAME = (INSMOD_OPT_UNUSED << x), /* d */
112	MODPROBE_OPT_LIST_ONLY = (INSMOD_OPT_UNUSED << 1), /* l */
113	//MODPROBE_OPT_SHOW_ONLY= (INSMOD_OPT_UNUSED << x), /* n */
114	MODPROBE_OPT_REMOVE = (INSMOD_OPT_UNUSED << 2), /* r */
115	//MODPROBE_OPT_RESTRICT = (INSMOD_OPT_UNUSED << x), /* t */
116	//MODPROBE_OPT_VERONLY = (INSMOD_OPT_UNUSED << x), /* V */
117	//MODPROBE_OPT_CONFIGFILE=(INSMOD_OPT_UNUSED << x), /* C */
118	MODPROBE_OPT_BLACKLIST = (INSMOD_OPT_UNUSED << 3) * ENABLE_FEATURE_MODPROBE_BLACKLIST,
119	};
120
121	#define MODULE_FLAG_LOADED 0x0001
122	#define MODULE_FLAG_NEED_DEPS 0x0002
123	/* "was seen in modules.dep": */
124	#define MODULE_FLAG_FOUND_IN_MODDEP 0x0004
125	#define MODULE_FLAG_BLACKLISTED 0x0008
126
127	struct module_entry { /* I'll call it ME. */
128	unsigned flags;
129	char modname; / stripped of /path/, .ext and s/-/_/g */
130	const char probed_name; / verbatim as seen on cmdline */
131	char options; / options from config files */
132	llist_t realnames; / strings. if this module is an alias, */
133	/* real module name is one of these. */
134	//Can there really be more than one? Example from real kernel?
135	llist_t deps; / strings. modules we depend on */
136	};
137
138	struct globals {
139	llist_t db; / MEs of all modules ever seen (caching for speed) */
140	llist_t probes; / MEs of module(s) requested on cmdline */
141	char cmdline_mopts; / module options from cmdline */
142	int num_unresolved_deps;
143	/* bool. "Did we have 'symbol:FOO' requested on cmdline?" */
144	smallint need_symbols;
145	} FIX_ALIASING;
146	#define G ((struct globals)&bb_common_bufsiz1)
147	#define INIT_G() do { } while (0)
148
149
150	static int read_config(const char *path);
151
152	static char gather_options_str(char opts, const char *append)
153	{
154	/* Speed-optimized. We call gather_options_str many times. */
155	if (append) {
156	if (opts == NULL) {
157	opts = xstrdup(append);
158	} else {
159	int optlen = strlen(opts);
160	opts = xrealloc(opts, optlen + strlen(append) + 2);
161	sprintf(opts + optlen, " %s", append);
162	}
163	}
164	return opts;
165	}
166
167	static struct module_entry helper_get_module(const char module, int create)
168	{
169	char modname[MODULE_NAME_LEN];
170	struct module_entry *e;
171	llist_t *l;
172
173	filename2modname(module, modname);
174	for (l = G.db; l != NULL; l = l->link) {
175	e = (struct module_entry *) l->data;
176	if (strcmp(e->modname, modname) == 0)
177	return e;
178	}
179	if (!create)
180	return NULL;
181
182	e = xzalloc(sizeof(*e));
183	e->modname = xstrdup(modname);
184	llist_add_to(&G.db, e);
185
186	return e;
187	}
188	static struct module_entry get_or_add_modentry(const char module)
189	{
190	return helper_get_module(module, 1);
191	}
192	static struct module_entry get_modentry(const char module)
193	{
194	return helper_get_module(module, 0);
195	}
196
197	static void add_probe(const char *name)
198	{
199	struct module_entry *m;
200
201	m = get_or_add_modentry(name);
202	if (!(option_mask32 & MODPROBE_OPT_REMOVE)
203	&& (m->flags & MODULE_FLAG_LOADED)
204	) {
205	DBG("skipping %s, it is already loaded", name);
206	return;
207	}
208
209	DBG("queuing %s", name);
210	m->probed_name = name;
211	m->flags \|= MODULE_FLAG_NEED_DEPS;
212	llist_add_to_end(&G.probes, m);
213	G.num_unresolved_deps++;
214	if (ENABLE_FEATURE_MODUTILS_SYMBOLS
215	&& strncmp(m->modname, "symbol:", 7) == 0
216	) {
217	G.need_symbols = 1;
218	}
219	}
220
221	static int FAST_FUNC config_file_action(const char *filename,
222	struct stat *statbuf UNUSED_PARAM,
223	void *userdata UNUSED_PARAM,
224	int depth UNUSED_PARAM)
225	{
226	char *tokens[3];
227	parser_t *p;
228	struct module_entry *m;
229	int rc = TRUE;
230
231	if (bb_basename(filename)[0] == '.')
232	goto error;
233
234	p = config_open2(filename, fopen_for_read);
235	if (p == NULL) {
236	rc = FALSE;
237	goto error;
238	}
239
240	while (config_read(p, tokens, 3, 2, "# \t", PARSE_NORMAL)) {
241	//Use index_in_strings?
242	if (strcmp(tokens[0], "alias") == 0) {
243	/* alias <wildcard> <modulename> */
244	llist_t *l;
245	char wildcard[MODULE_NAME_LEN];
246	char *rmod;
247
248	if (tokens[2] == NULL)
249	continue;
250	filename2modname(tokens[1], wildcard);
251
252	for (l = G.probes; l != NULL; l = l->link) {
253	m = (struct module_entry *) l->data;
254	if (fnmatch(wildcard, m->modname, 0) != 0)
255	continue;
256	rmod = filename2modname(tokens[2], NULL);
257	llist_add_to(&m->realnames, rmod);
258
259	if (m->flags & MODULE_FLAG_NEED_DEPS) {
260	m->flags &= ~MODULE_FLAG_NEED_DEPS;
261	G.num_unresolved_deps--;
262	}
263
264	m = get_or_add_modentry(rmod);
265	if (!(m->flags & MODULE_FLAG_NEED_DEPS)) {
266	m->flags \|= MODULE_FLAG_NEED_DEPS;
267	G.num_unresolved_deps++;
268	}
269	}
270	} else if (strcmp(tokens[0], "options") == 0) {
271	/* options <modulename> <option...> */
272	if (tokens[2] == NULL)
273	continue;
274	m = get_or_add_modentry(tokens[1]);
275	m->options = gather_options_str(m->options, tokens[2]);
276	} else if (strcmp(tokens[0], "include") == 0) {
277	/* include <filename> */
278	read_config(tokens[1]);
279	} else if (ENABLE_FEATURE_MODPROBE_BLACKLIST
280	&& strcmp(tokens[0], "blacklist") == 0
281	) {
282	/* blacklist <modulename> */
283	get_or_add_modentry(tokens[1])->flags \|= MODULE_FLAG_BLACKLISTED;
284	}
285	}
286	config_close(p);
287	error:
288	return rc;
289	}
290
291	static int read_config(const char *path)
292	{
293	return recursive_action(path, ACTION_RECURSE \| ACTION_QUIET,
294	config_file_action, NULL, NULL, 1);
295	}
296
297	static const char humanly_readable_name(struct module_entry m)
298	{
299	/* probed_name may be NULL. modname always exists. */
300	return m->probed_name ? m->probed_name : m->modname;
301	}
302
303	static char parse_and_add_kcmdline_module_options(char options, const char *modulename)
304	{
305	char *kcmdline_buf;
306	char *kcmdline;
307	char *kptr;
308	int len;
309
310	kcmdline_buf = xmalloc_open_read_close("/proc/cmdline", NULL);
311	if (!kcmdline_buf)
312	return options;
313
314	kcmdline = kcmdline_buf;
315	len = strlen(modulename);
316	while ((kptr = strsep(&kcmdline, "\n\t ")) != NULL) {
317	if (strncmp(modulename, kptr, len) != 0)
318	continue;
319	kptr += len;
320	if (*kptr != '.')
321	continue;
322	/* It is "modulename.xxxx" */
323	kptr++;
324	if (strchr(kptr, '=') != NULL) {
325	/* It is "modulename.opt=[val]" */
326	options = gather_options_str(options, kptr);
327	}
328	}
329	free(kcmdline_buf);
330
331	return options;
332	}
333
334	/* Return: similar to bb_init_module:
335	* 0 on success,
336	* -errno on open/read error,
337	* errno on init_module() error
338	*/
339	/* NB: INSMOD_OPT_SILENT bit suppresses ONLY non-existent modules,
340	* not deleted ones (those are still listed in modules.dep).
341	* module-init-tools version 3.4:
342	* # modprobe bogus
343	* FATAL: Module bogus not found. [exitcode 1]
344	* # modprobe -q bogus [silent, exitcode still 1]
345	* but:
346	* # rm kernel/drivers/net/dummy.ko
347	* # modprobe -q dummy
348	* FATAL: Could not open '/lib/modules/xxx/kernel/drivers/net/dummy.ko': No such file or directory
349	* [exitcode 1]
350	*/
351	static int do_modprobe(struct module_entry *m)
352	{
353	struct module_entry m2 = m2; / for compiler */
354	char fn, options;
355	int rc, first;
356	llist_t *l;
357
358	if (!(m->flags & MODULE_FLAG_FOUND_IN_MODDEP)) {
359	if (!(option_mask32 & INSMOD_OPT_SILENT))
360	bb_error_msg("module %s not found in modules.dep",
361	humanly_readable_name(m));
362	return -ENOENT;
363	}
364	DBG("do_modprob'ing %s", m->modname);
365
366	if (!(option_mask32 & MODPROBE_OPT_REMOVE))
367	m->deps = llist_rev(m->deps);
368
369	for (l = m->deps; l != NULL; l = l->link)
370	DBG("dep: %s", l->data);
371
372	first = 1;
373	rc = 0;
374	while (m->deps) {
375	rc = 0;
376	fn = llist_pop(&m->deps); /* we leak it */
377	m2 = get_or_add_modentry(fn);
378
379	if (option_mask32 & MODPROBE_OPT_REMOVE) {
380	/* modprobe -r */
381	if (m2->flags & MODULE_FLAG_LOADED) {
382	rc = bb_delete_module(m2->modname, O_EXCL);
383	if (rc) {
384	if (first) {
385	bb_error_msg("can't unload module %s: %s",
386	humanly_readable_name(m2),
387	moderror(rc));
388	break;
389	}
390	} else {
391	m2->flags &= ~MODULE_FLAG_LOADED;
392	}
393	}
394	/* do not error out if deps fail to unload */
395	first = 0;
396	continue;
397	}
398
399	if (m2->flags & MODULE_FLAG_LOADED) {
400	DBG("%s is already loaded, skipping", fn);
401	continue;
402	}
403
404	options = m2->options;
405	m2->options = NULL;
406	options = parse_and_add_kcmdline_module_options(options, m2->modname);
407	if (m == m2)
408	options = gather_options_str(options, G.cmdline_mopts);
409	rc = bb_init_module(fn, options);
410	DBG("loaded %s '%s', rc:%d", fn, options, rc);
411	if (rc == EEXIST)
412	rc = 0;
413	free(options);
414	if (rc) {
415	bb_error_msg("can't load module %s (%s): %s",
416	humanly_readable_name(m2),
417	fn,
418	moderror(rc)
419	);
420	break;
421	}
422	m2->flags \|= MODULE_FLAG_LOADED;
423	}
424
425	return rc;
426	}
427
428	static void load_modules_dep(void)
429	{
430	struct module_entry *m;
431	char colon, tokens[2];
432	parser_t *p;
433
434	/* Modprobe does not work at all without modules.dep,
435	* even if the full module name is given. Returning error here
436	* was making us later confuse user with this message:
437	* "module /full/path/to/existing/file/module.ko not found".
438	* It's better to die immediately, with good message.
439	* xfopen_for_read provides that. */
440	p = config_open2(CONFIG_DEFAULT_DEPMOD_FILE, xfopen_for_read);
441
442	while (G.num_unresolved_deps
443	&& config_read(p, tokens, 2, 1, "# \t", PARSE_NORMAL)
444	) {
445	colon = last_char_is(tokens[0], ':');
446	if (colon == NULL)
447	continue;
448	*colon = 0;
449
450	m = get_modentry(tokens[0]);
451	if (m == NULL)
452	continue;
453
454	/* Optimization... */
455	if ((m->flags & MODULE_FLAG_LOADED)
456	&& !(option_mask32 & MODPROBE_OPT_REMOVE)
457	) {
458	DBG("skip deps of %s, it's already loaded", tokens[0]);
459	continue;
460	}
461
462	m->flags \|= MODULE_FLAG_FOUND_IN_MODDEP;
463	if ((m->flags & MODULE_FLAG_NEED_DEPS) && (m->deps == NULL)) {
464	G.num_unresolved_deps--;
465	llist_add_to(&m->deps, xstrdup(tokens[0]));
466	if (tokens[1])
467	string_to_llist(tokens[1], &m->deps, " \t");
468	} else
469	DBG("skipping dep line");
470	}
471	config_close(p);
472	}
473
474	int modprobe_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
475	int modprobe_main(int argc UNUSED_PARAM, char **argv)
476	{
477	struct utsname uts;
478	int rc;
479	unsigned opt;
480	struct module_entry *me;
481
482	opt_complementary = MODPROBE_COMPLEMENTARY;
483	opt = getopt32(argv, INSMOD_OPTS MODPROBE_OPTS INSMOD_ARGS);
484	argv += optind;
485
486	/* Goto modules location */
487	xchdir(CONFIG_DEFAULT_MODULES_DIR);
488	uname(&uts);
489	xchdir(uts.release);
490
491	if (opt & MODPROBE_OPT_LIST_ONLY) {
492	char name[MODULE_NAME_LEN];
493	char colon, tokens[2];
494	parser_t *p = config_open2(CONFIG_DEFAULT_DEPMOD_FILE, xfopen_for_read);
495
496	while (config_read(p, tokens, 2, 1, "# \t", PARSE_NORMAL)) {
497	colon = last_char_is(tokens[0], ':');
498	if (!colon)
499	continue;
500	*colon = '\0';
501	filename2modname(tokens[0], name);
502	if (!argv[0])
503	puts(tokens[0]);
504	else {
505	int i;
506	for (i = 0; argv[i]; i++) {
507	if (fnmatch(argv[i], name, 0) == 0) {
508	puts(tokens[0]);
509	}
510	}
511	}
512	}
513	return EXIT_SUCCESS;
514	}
515
516	/* Yes, for some reason -l ignores -s... */
517	if (opt & INSMOD_OPT_SYSLOG)
518	logmode = LOGMODE_SYSLOG;
519
520	if (!argv[0]) {
521	if (opt & MODPROBE_OPT_REMOVE) {
522	/* "modprobe -r" (w/o params).
523	* "If name is NULL, all unused modules marked
524	* autoclean will be removed".
525	*/
526	if (bb_delete_module(NULL, O_NONBLOCK \| O_EXCL) != 0)
527	bb_perror_msg_and_die("rmmod");
528	}
529	return EXIT_SUCCESS;
530	}
531
532	/* Retrieve module names of already loaded modules */
533	{
534	char *s;
535	parser_t *parser = config_open2("/proc/modules", fopen_for_read);
536	while (config_read(parser, &s, 1, 1, "# \t", PARSE_NORMAL & ~PARSE_GREEDY))
537	get_or_add_modentry(s)->flags \|= MODULE_FLAG_LOADED;
538	config_close(parser);
539	}
540
541	if (opt & (MODPROBE_OPT_INSERT_ALL \| MODPROBE_OPT_REMOVE)) {
542	/* Each argument is a module name */
543	do {
544	DBG("adding module %s", *argv);
545	add_probe(*argv++);
546	} while (*argv);
547	} else {
548	/* First argument is module name, rest are parameters */
549	DBG("probing just module %s", *argv);
550	add_probe(argv[0]);
551	G.cmdline_mopts = parse_cmdline_module_options(argv);
552	}
553
554	/* Happens if all requested modules are already loaded */
555	if (G.probes == NULL)
556	return EXIT_SUCCESS;
557
558	read_config("/etc/modprobe.conf");
559	read_config("/etc/modprobe.d");
560	if (ENABLE_FEATURE_MODUTILS_SYMBOLS && G.need_symbols)
561	read_config("modules.symbols");
562	load_modules_dep();
563	if (ENABLE_FEATURE_MODUTILS_ALIAS && G.num_unresolved_deps) {
564	read_config("modules.alias");
565	load_modules_dep();
566	}
567
568	rc = 0;
569	while ((me = llist_pop(&G.probes)) != NULL) {
570	if (me->realnames == NULL) {
571	DBG("probing by module name");
572	/* This is not an alias. Literal names are blacklisted
573	* only if '-b' is given.
574	*/
575	if (!(opt & MODPROBE_OPT_BLACKLIST)
576	\|\| !(me->flags & MODULE_FLAG_BLACKLISTED)
577	) {
578	rc \|= do_modprobe(me);
579	}
580	continue;
581	}
582
583	/* Probe all real names for the alias */
584	do {
585	char *realname = llist_pop(&me->realnames);
586	struct module_entry *m2;
587
588	DBG("probing alias %s by realname %s", me->modname, realname);
589	m2 = get_or_add_modentry(realname);
590	if (!(m2->flags & MODULE_FLAG_BLACKLISTED)
591	&& (!(m2->flags & MODULE_FLAG_LOADED)
592	\|\| (opt & MODPROBE_OPT_REMOVE))
593	) {
594	//TODO: we can pass "me" as 2nd param to do_modprobe,
595	//and make do_modprobe emit more meaningful error messages
596	//with alias name included, not just module name alias resolves to.
597	rc \|= do_modprobe(m2);
598	}
599	free(realname);
600	} while (me->realnames != NULL);
601	}
602
603	return (rc != 0);
604	}