busybox/modutils/modprobe.c
2004-08-16 10:22:34 +00:00

676 lines
14 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Modprobe written from scratch for BusyBox
*
* Copyright (c) 2002 by Robert Griebl, griebl@gmx.de
* Copyright (c) 2003 by Andrew Dennison, andrew.dennison@motec.com.au
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <sys/utsname.h>
#include <getopt.h>
#include <stdlib.h>
#include <unistd.h>
#include <syslog.h>
#include <string.h>
#include <ctype.h>
#include <fcntl.h>
#include "busybox.h"
struct dep_t {
char * m_module;
char * m_options;
int m_isalias : 1;
int m_reserved : 15;
int m_depcnt : 16;
char ** m_deparr;
struct dep_t * m_next;
};
struct mod_list_t {
char * m_module;
char * m_options;
struct mod_list_t * m_prev;
struct mod_list_t * m_next;
};
static struct dep_t *depend;
static int autoclean, show_only, quiet, do_syslog, verbose;
static int k_version;
int parse_tag_value ( char *buffer, char **ptag, char **pvalue )
{
char *tag, *value;
while ( isspace ( *buffer ))
buffer++;
tag = value = buffer;
while ( !isspace ( *value ))
if (!*value) return 0;
else value++;
*value++ = 0;
while ( isspace ( *value ))
value++;
if (!*value) return 0;
*ptag = tag;
*pvalue = value;
return 1;
}
/* Jump through hoops to simulate how fgets() grabs just one line at a
* time... Don't use any stdio since modprobe gets called from a kernel
* thread and stdio junk can overflow the limited stack...
*/
static char *reads ( int fd, char *buffer, size_t len )
{
int n = read ( fd, buffer, len );
if ( n > 0 ) {
char *p;
buffer [len-1] = 0;
p = strchr ( buffer, '\n' );
if ( p ) {
off_t offset;
offset = lseek ( fd, 0L, SEEK_CUR ); // Get the current file descriptor offset
lseek ( fd, offset-n + (p-buffer) + 1, SEEK_SET ); // Set the file descriptor offset to right after the \n
p[1] = 0;
}
return buffer;
}
else
return 0;
}
static struct dep_t *build_dep ( void )
{
int fd;
struct utsname un;
struct dep_t *first = 0;
struct dep_t *current = 0;
char buffer[2048];
char *filename = buffer;
int continuation_line = 0;
k_version = 0;
if ( uname ( &un ))
return 0;
// check for buffer overflow in following code
if ( bb_strlen ( un.release ) > ( sizeof( buffer ) - 64 )) {
return 0;
}
if (un.release[0] == '2') {
k_version = un.release[2] - '0';
}
strcpy ( filename, "/lib/modules/" );
strcat ( filename, un.release );
strcat ( filename, "/modules.dep" );
if (( fd = open ( filename, O_RDONLY )) < 0 ) {
/* Ok, that didn't work. Fall back to looking in /lib/modules */
if (( fd = open ( "/lib/modules/modules.dep", O_RDONLY )) < 0 ) {
return 0;
}
}
while ( reads ( fd, buffer, sizeof( buffer ))) {
int l = bb_strlen ( buffer );
char *p = 0;
while ( isspace ( buffer [l-1] )) {
buffer [l-1] = 0;
l--;
}
if ( l == 0 ) {
continuation_line = 0;
continue;
}
if ( !continuation_line ) {
char *col = strchr ( buffer, ':' );
if ( col ) {
char *mods;
char *mod;
int ext = 0;
*col = 0;
mods = strrchr ( buffer, '/' );
if ( !mods )
mods = buffer;
else
mods++;
#if defined(CONFIG_FEATURE_2_6_MODULES)
if ((k_version > 4) && ( *(col-3) == '.' ) &&
( *(col-2) == 'k' ) && ( *(col-1) == 'o' ))
ext = 3;
else
#endif
if (( *(col-2) == '.' ) && ( *(col-1) == 'o' ))
ext = 2;
mod = bb_xstrndup ( buffer, col - buffer );
if ( !current ) {
first = current = (struct dep_t *) xmalloc ( sizeof ( struct dep_t ));
}
else {
current-> m_next = (struct dep_t *) xmalloc ( sizeof ( struct dep_t ));
current = current-> m_next;
}
current-> m_module = mod;
current-> m_options = 0;
current-> m_isalias = 0;
current-> m_depcnt = 0;
current-> m_deparr = 0;
current-> m_next = 0;
//printf ( "%s:\n", mod );
p = col + 1;
}
else
p = 0;
}
else
p = buffer;
while ( p && *p && isblank(*p))
p++;
if ( p && *p ) {
char *end = &buffer [l-1];
char *deps;
char *dep;
char *next;
int ext = 0;
while ( isblank ( *end ) || ( *end == '\\' ))
end--;
do
{
next = strchr (p, ' ' );
if (next)
{
*next = 0;
next--;
}
else
next = end;
deps = strrchr ( p, '/' );
if ( !deps || ( deps < p )) {
deps = p;
while ( isblank ( *deps ))
deps++;
}
else
deps++;
#if defined(CONFIG_FEATURE_2_6_MODULES)
if ((k_version > 4) && ( *(next-2) == '.' ) && *(next-1) == 'k' &&
( *next == 'o' ))
ext = 3;
else
#endif
if (( *(next-1) == '.' ) && ( *next == 'o' ))
ext = 2;
/* Cope with blank lines */
if ((next-deps-ext+1) <= 0)
continue;
dep = bb_xstrndup ( deps, next - deps - ext + 1 );
current-> m_depcnt++;
current-> m_deparr = (char **) xrealloc ( current-> m_deparr,
sizeof ( char *) * current-> m_depcnt );
current-> m_deparr [current-> m_depcnt - 1] = dep;
//printf ( " %d) %s\n", current-> m_depcnt, current-> m_deparr [current-> m_depcnt -1] );
p = next + 2;
} while (next < end);
}
if ( buffer [l-1] == '\\' )
continuation_line = 1;
else
continuation_line = 0;
}
close ( fd );
// alias parsing is not 100% correct (no correct handling of continuation lines within an alias) !
#if defined(CONFIG_FEATURE_2_6_MODULES)
if (( fd = open ( "/etc/modprobe.conf", O_RDONLY )) < 0 )
#endif
if (( fd = open ( "/etc/modules.conf", O_RDONLY )) < 0 )
if (( fd = open ( "/etc/conf.modules", O_RDONLY )) < 0 )
return first;
continuation_line = 0;
while ( reads ( fd, buffer, sizeof( buffer ))) {
int l;
char *p;
p = strchr ( buffer, '#' );
if ( p )
*p = 0;
l = bb_strlen ( buffer );
while ( l && isspace ( buffer [l-1] )) {
buffer [l-1] = 0;
l--;
}
if ( l == 0 ) {
continuation_line = 0;
continue;
}
if ( !continuation_line ) {
if (( strncmp ( buffer, "alias", 5 ) == 0 ) && isspace ( buffer [5] )) {
char *alias, *mod;
if ( parse_tag_value ( buffer + 6, &alias, &mod )) {
// fprintf ( stderr, "ALIAS: '%s' -> '%s'\n", alias, mod );
if ( !current ) {
first = current = (struct dep_t *) xcalloc ( 1, sizeof ( struct dep_t ));
}
else {
current-> m_next = (struct dep_t *) xcalloc ( 1, sizeof ( struct dep_t ));
current = current-> m_next;
}
current-> m_module = bb_xstrdup ( alias );
current-> m_isalias = 1;
if (( strcmp ( mod, "off" ) == 0 ) || ( strcmp ( mod, "null" ) == 0 )) {
current-> m_depcnt = 0;
current-> m_deparr = 0;
}
else {
current-> m_depcnt = 1;
current-> m_deparr = xmalloc ( 1 * sizeof( char * ));
current-> m_deparr[0] = bb_xstrdup ( mod );
}
current-> m_next = 0;
}
}
else if (( strncmp ( buffer, "options", 7 ) == 0 ) && isspace ( buffer [7] )) {
char *mod, *opt;
if ( parse_tag_value ( buffer + 8, &mod, &opt )) {
struct dep_t *dt;
for ( dt = first; dt; dt = dt-> m_next ) {
if ( strcmp ( dt-> m_module, mod ) == 0 )
break;
}
if ( dt ) {
dt-> m_options = xrealloc ( dt-> m_options, bb_strlen( opt ) + 1 );
strcpy ( dt-> m_options, opt );
// fprintf ( stderr, "OPTION: '%s' -> '%s'\n", dt-> m_module, dt-> m_options );
}
}
}
}
}
close ( fd );
return first;
}
/* check if /lib/modules/bar/foo.ko belongs to module foo */
/* return 1 = found, 0 = not found */
static int mod_strcmp ( const char *mod_path, const char *mod_name )
{
/* last path component */
const char *last_comp = strrchr (mod_path, '/');
const char *mod_ext = ".o";
#if defined(CONFIG_FEATURE_2_6_MODULES)
if ( k_version > 4 )
mod_ext = ".ko";
#endif
last_comp = last_comp ? last_comp + 1 : mod_path;
return (strncmp(last_comp,
mod_name,
strlen(mod_name)) == 0 ) &&
((strcmp(last_comp + strlen (mod_name), mod_ext) == 0) || last_comp[strlen(mod_name)] == 0) &&
(strcmp(mod_path + strlen(mod_path) -
strlen(mod_ext), mod_ext) == 0);
}
/* return 1 = loaded, 0 = not loaded, -1 = can't tell */
static int already_loaded (const char *name)
{
int fd;
char buffer[4096];
fd = open ("/proc/modules", O_RDONLY);
if (fd < 0)
return -1;
while ( reads ( fd, buffer, sizeof( buffer ))) {
char *p;
p = strchr (buffer, ' ');
if (p) {
*p = 0;
if (mod_strcmp (name, buffer)) {
close (fd);
return 1;
}
}
}
close (fd);
return 0;
}
static int mod_process ( struct mod_list_t *list, int do_insert )
{
char lcmd [4096];
int rc = 0;
while ( list ) {
*lcmd = '\0';
if ( do_insert ) {
if (already_loaded (list->m_module) != 1)
snprintf ( lcmd, sizeof( lcmd ) - 1, "insmod %s %s %s %s %s",
do_syslog ? "-s" : "", autoclean ? "-k" : "",
quiet ? "-q" : "", list-> m_module, list-> m_options ?
list-> m_options : "" );
} else {
if (already_loaded (list->m_module) != 0)
snprintf ( lcmd, sizeof( lcmd ) - 1, "rmmod %s %s",
do_syslog ? "-s" : "", list-> m_module );
}
if (*lcmd) {
if (verbose) {
printf("%s\n", lcmd);
}
if (!show_only) {
int rc2 = system(lcmd);
if (do_insert) {
rc = rc2; /* only last module matters */
}
else if (!rc2) {
rc = 0; /* success if remove any mod */
}
}
}
list = do_insert ? list-> m_prev : list-> m_next;
}
return (show_only) ? 0 : rc;
}
static void check_dep ( char *mod, struct mod_list_t **head, struct mod_list_t **tail )
{
struct mod_list_t *find;
struct dep_t *dt;
char *opt = 0;
int lm;
// remove .o extension
lm = bb_strlen ( mod );
#if defined(CONFIG_FEATURE_2_6_MODULES)
if ((k_version > 4) && ( mod [lm-3] == '.' ) &&
( mod [lm-2] == 'k' ) && ( mod [lm-1] == 'o' ))
mod [lm-3] = 0;
else
#endif
if (( mod [lm-2] == '.' ) && ( mod [lm-1] == 'o' ))
mod [lm-2] = 0;
// check dependencies
for ( dt = depend; dt; dt = dt-> m_next ) {
if ( mod_strcmp ( dt-> m_module, mod )) {
mod = dt-> m_module;
opt = dt-> m_options;
break;
}
}
// resolve alias names
while ( dt && dt-> m_isalias ) {
if ( dt-> m_depcnt == 1 ) {
struct dep_t *adt;
for ( adt = depend; adt; adt = adt-> m_next ) {
if ( strcmp ( adt-> m_module, dt-> m_deparr [0] ) == 0 )
break;
}
if ( adt ) {
dt = adt;
mod = dt-> m_module;
if ( !opt )
opt = dt-> m_options;
}
else
return;
}
else
return;
}
// search for duplicates
for ( find = *head; find; find = find-> m_next ) {
if ( !strcmp ( mod, find-> m_module )) {
// found -> dequeue it
if ( find-> m_prev )
find-> m_prev-> m_next = find-> m_next;
else
*head = find-> m_next;
if ( find-> m_next )
find-> m_next-> m_prev = find-> m_prev;
else
*tail = find-> m_prev;
break; // there can be only one duplicate
}
}
if ( !find ) { // did not find a duplicate
find = (struct mod_list_t *) xmalloc ( sizeof(struct mod_list_t));
find-> m_module = mod;
find-> m_options = opt;
}
// enqueue at tail
if ( *tail )
(*tail)-> m_next = find;
find-> m_prev = *tail;
find-> m_next = 0;
if ( !*head )
*head = find;
*tail = find;
if ( dt ) {
int i;
for ( i = 0; i < dt-> m_depcnt; i++ )
check_dep ( dt-> m_deparr [i], head, tail );
}
}
static int mod_insert ( char *mod, int argc, char **argv )
{
struct mod_list_t *tail = 0;
struct mod_list_t *head = 0;
int rc;
// get dep list for module mod
check_dep ( mod, &head, &tail );
if ( head && tail ) {
#if defined(CONFIG_FEATURE_2_6_MODULES)
if ( argc ) {
int i;
int l = 0;
// append module args
for ( i = 0; i < argc; i++ )
l += ( bb_strlen ( argv [i] ) + 1 );
head-> m_options = xrealloc ( head-> m_options, l + 1 );
head-> m_options [0] = 0;
for ( i = 0; i < argc; i++ ) {
strcat ( head-> m_options, argv [i] );
strcat ( head-> m_options, " " );
}
}
#endif
// process tail ---> head
rc = mod_process ( tail, 1 );
}
else
rc = 1;
return rc;
}
static int mod_remove ( char *mod )
{
int rc;
static struct mod_list_t rm_a_dummy = { "-a", 0, 0 };
struct mod_list_t *head = 0;
struct mod_list_t *tail = 0;
if ( mod )
check_dep ( mod, &head, &tail );
else // autoclean
head = tail = &rm_a_dummy;
if ( head && tail )
rc = mod_process ( head, 0 ); // process head ---> tail
else
rc = 1;
return rc;
}
extern int modprobe_main(int argc, char** argv)
{
int opt;
int remove_opt = 0;
autoclean = show_only = quiet = do_syslog = verbose = 0;
while ((opt = getopt(argc, argv, "acdklnqrst:vVC:")) != -1) {
switch(opt) {
case 'c': // no config used
case 'l': // no pattern matching
return EXIT_SUCCESS;
break;
case 'C': // no config used
case 't': // no pattern matching
bb_error_msg_and_die("-t and -C not supported");
case 'a': // ignore
case 'd': // ignore
break;
case 'k':
autoclean++;
break;
case 'n':
show_only++;
break;
case 'q':
quiet++;
break;
case 'r':
remove_opt++;
break;
case 's':
do_syslog++;
break;
case 'v':
verbose++;
break;
case 'V':
default:
bb_show_usage();
break;
}
}
depend = build_dep ( );
if ( !depend )
bb_error_msg_and_die ( "could not parse modules.dep\n" );
if (remove_opt) {
int rc = EXIT_SUCCESS;
do {
if (mod_remove ( optind < argc ?
bb_xstrdup (argv [optind]) : NULL )) {
bb_error_msg ("failed to remove module %s",
argv [optind] );
rc = EXIT_FAILURE;
}
} while ( ++optind < argc );
return rc;
}
if (optind >= argc)
bb_error_msg_and_die ( "No module or pattern provided\n" );
if ( mod_insert ( bb_xstrdup ( argv [optind] ), argc - optind - 1, argv + optind + 1 ))
bb_error_msg_and_die ( "failed to load module %s", argv [optind] );
return EXIT_SUCCESS;
}