blob: ae7c29cd133962982d637dda8a1cbca81105f8a8 [file] [log] [blame]
/* vi: set sw=4 ts=4: */
/*
* simplified modprobe
*
* Copyright (c) 2008 Vladimir Dronnikov
* Copyright (c) 2008 Bernhard 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 read_module 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;
}
#if ENABLE_FEATURE_MODPROBE_SMALL_ZIPPED
# define read_module xmalloc_open_zipped_read_close
#else
# define read_module xmalloc_open_read_close
#endif
/* 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 = read_module(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 = read_module(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);
//TODO: use zeroing version of xrealloc_vector?
modinfo[cur].pathname = xstrdup(pathname);
modinfo[cur].aliases = NULL;
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(DEPFILE_BB, "r");
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);
//TODO: use zeroing version of xrealloc_vector?
modinfo[cur+1].pathname = NULL;
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)
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
static int already_loaded(const char *name)
{
int ret = 0;
int len = strlen(name);
char *line;
FILE* modules;
modules = xfopen("/proc/modules", "r");
while ((line = xmalloc_fgets(modules)) != NULL) {
if (strncmp(line, name, len) == 0 && line[len] == ' ') {
free(line);
ret = 1;
break;
}
free(line);
}
fclose(modules);
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);
/* insmod -> load it */
if (!is_rmmod) {
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));
}
}
}
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 a 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 dependancy 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];
USE_FEATURE_MODPROBE_SMALL_OPTIONS_ON_CMDLINE(char *options;)
/* are we lsmod? -> just dump /proc/modules */
if ('l' == applet0) {
xprint_and_close_file(xfopen("/proc/modules", "r"));
return EXIT_SUCCESS;
}
INIT_G();
/* Prevent ugly corner cases with no modules at all */
modinfo = xzalloc(sizeof(modinfo[0]));
/* 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;
}
/* 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
/* Try to load modprobe.dep.bb */
load_dep_bb();
/* Load/remove modules.
* Only rmmod loops here, insmod/modprobe has only argv[0] */
do {
process_module(*argv++, options);
} while (*argv);
if (ENABLE_FEATURE_CLEAN_UP) {
USE_FEATURE_MODPROBE_SMALL_OPTIONS_ON_CMDLINE(free(options);)
}
return EXIT_SUCCESS;
}