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devfsd.c
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/* vi: set sw=4 ts=4: */
/*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
/*
devfsd implementation for busybox
Copyright (C) 2003 by Tito Ragusa <farmatito@tiscali.it>
Busybox version is based on some previous work and ideas
Copyright (C) [2003] by [Matteo Croce] <3297627799@wind.it>
devfsd.c
Main file for devfsd (devfs daemon for Linux).
Copyright (C) 1998-2002 Richard Gooch
devfsd.h
Header file for devfsd (devfs daemon for Linux).
Copyright (C) 1998-2000 Richard Gooch
compat_name.c
Compatibility name file for devfsd (build compatibility names).
Copyright (C) 1998-2002 Richard Gooch
expression.c
This code provides Borne Shell-like expression expansion.
Copyright (C) 1997-1999 Richard Gooch
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., 675 Mass Ave, Cambridge, MA 02139, USA.
Richard Gooch may be reached by email at rgooch@atnf.csiro.au
The postal address is:
Richard Gooch, c/o ATNF, P. O. Box 76, Epping, N.S.W., 2121, Australia.
*/
//config:config DEVFSD
//config: bool "devfsd (obsolete)"
//config: default n
//config: select FEATURE_SYSLOG
//config: help
//config: This is deprecated and should NOT be used anymore.
//config: Use linux >= 2.6 (optionally with hotplug) and mdev instead!
//config: See docs/mdev.txt for detailed instructions on how to use mdev
//config: instead.
//config:
//config: Provides compatibility with old device names on a devfs systems.
//config: You should set it to true if you have devfs enabled.
//config: The following keywords in devsfd.conf are supported:
//config: "CLEAR_CONFIG", "INCLUDE", "OPTIONAL_INCLUDE", "RESTORE",
//config: "PERMISSIONS", "EXECUTE", "COPY", "IGNORE",
//config: "MKOLDCOMPAT", "MKNEWCOMPAT","RMOLDCOMPAT", "RMNEWCOMPAT".
//config:
//config: But only if they are written UPPERCASE!!!!!!!!
//config:
//config:config DEVFSD_MODLOAD
//config: bool "Adds support for MODLOAD keyword in devsfd.conf"
//config: default y
//config: depends on DEVFSD
//config: help
//config: This actually doesn't work with busybox modutils but needs
//config: the external modutils.
//config:
//config:config DEVFSD_FG_NP
//config: bool "Enable the -fg and -np options"
//config: default y
//config: depends on DEVFSD
//config: help
//config: -fg Run the daemon in the foreground.
//config: -np Exit after parsing config. Do not poll for events.
//config:
//config:config DEVFSD_VERBOSE
//config: bool "Increases logging (and size)"
//config: default y
//config: depends on DEVFSD
//config: help
//config: Increases logging to stderr or syslog.
//config:
//config:config FEATURE_DEVFS
//config: bool "Use devfs names for all devices (obsolete)"
//config: default n
//config: help
//config: This is obsolete and should NOT be used anymore.
//config: Use linux >= 2.6 (optionally with hotplug) and mdev instead!
//config:
//config: For legacy systems -- if there is no way around devfsd -- this
//config: tells busybox to look for names like /dev/loop/0 instead of
//config: /dev/loop0. If your /dev directory has normal names instead of
//config: devfs names, you don't want this.
//applet:IF_DEVFSD(APPLET(devfsd, BB_DIR_SBIN, BB_SUID_DROP))
//kbuild:lib-$(CONFIG_DEVFSD) += devfsd.o
//usage:#define devfsd_trivial_usage
//usage: "mntpnt [-v]" IF_DEVFSD_FG_NP("[-fg][-np]")
//usage:#define devfsd_full_usage "\n\n"
//usage: "Manage devfs permissions and old device name symlinks\n"
//usage: "\n mntpnt The mount point where devfs is mounted"
//usage: "\n -v Print the protocol version numbers for devfsd"
//usage: "\n and the kernel-side protocol version and exit"
//usage: IF_DEVFSD_FG_NP(
//usage: "\n -fg Run in foreground"
//usage: "\n -np Exit after parsing the configuration file"
//usage: "\n and processing synthetic REGISTER events,"
//usage: "\n don't poll for events"
//usage: )
#include "libbb.h"
#include "xregex.h"
#include <syslog.h>
#include <sys/un.h>
#include <sys/sysmacros.h>
/* Various defines taken from linux/major.h */
#define IDE0_MAJOR 3
#define IDE1_MAJOR 22
#define IDE2_MAJOR 33
#define IDE3_MAJOR 34
#define IDE4_MAJOR 56
#define IDE5_MAJOR 57
#define IDE6_MAJOR 88
#define IDE7_MAJOR 89
#define IDE8_MAJOR 90
#define IDE9_MAJOR 91
/* Various defines taken from linux/devfs_fs.h */
#define DEVFSD_PROTOCOL_REVISION_KERNEL 5
#define DEVFSD_IOCTL_BASE 'd'
/* These are the various ioctls */
#define DEVFSDIOC_GET_PROTO_REV _IOR(DEVFSD_IOCTL_BASE, 0, int)
#define DEVFSDIOC_SET_EVENT_MASK _IOW(DEVFSD_IOCTL_BASE, 2, int)
#define DEVFSDIOC_RELEASE_EVENT_QUEUE _IOW(DEVFSD_IOCTL_BASE, 3, int)
#define DEVFSDIOC_SET_CONFIG_DEBUG_MASK _IOW(DEVFSD_IOCTL_BASE, 4, int)
#define DEVFSD_NOTIFY_REGISTERED 0
#define DEVFSD_NOTIFY_UNREGISTERED 1
#define DEVFSD_NOTIFY_ASYNC_OPEN 2
#define DEVFSD_NOTIFY_CLOSE 3
#define DEVFSD_NOTIFY_LOOKUP 4
#define DEVFSD_NOTIFY_CHANGE 5
#define DEVFSD_NOTIFY_CREATE 6
#define DEVFSD_NOTIFY_DELETE 7
#define DEVFS_PATHLEN 1024
/* Never change this otherwise the binary interface will change */
struct devfsd_notify_struct {
/* Use native C types to ensure same types in kernel and user space */
unsigned int type; /* DEVFSD_NOTIFY_* value */
unsigned int mode; /* Mode of the inode or device entry */
unsigned int major; /* Major number of device entry */
unsigned int minor; /* Minor number of device entry */
unsigned int uid; /* Uid of process, inode or device entry */
unsigned int gid; /* Gid of process, inode or device entry */
unsigned int overrun_count; /* Number of lost events */
unsigned int namelen; /* Number of characters not including '\0' */
/* The device name MUST come last */
char devname[DEVFS_PATHLEN]; /* This will be '\0' terminated */
};
#define BUFFER_SIZE 16384
#define DEVFSD_VERSION "1.3.25"
#define CONFIG_FILE "/etc/devfsd.conf"
#define MODPROBE "/sbin/modprobe"
#define MODPROBE_SWITCH_1 "-k"
#define MODPROBE_SWITCH_2 "-C"
#define CONFIG_MODULES_DEVFS "/etc/modules.devfs"
#define MAX_ARGS (6 + 1)
#define MAX_SUBEXPR 10
#define STRING_LENGTH 255
/* for get_uid_gid() */
#define UID 0
#define GID 1
/* fork_and_execute() */
# define DIE 1
# define NO_DIE 0
/* for dir_operation() */
#define RESTORE 0
#define SERVICE 1
#define READ_CONFIG 2
/* Update only after changing code to reflect new protocol */
#define DEVFSD_PROTOCOL_REVISION_DAEMON 5
/* Compile-time check */
#if DEVFSD_PROTOCOL_REVISION_KERNEL != DEVFSD_PROTOCOL_REVISION_DAEMON
#error protocol version mismatch. Update your kernel headers
#endif
#define AC_PERMISSIONS 0
#define AC_MODLOAD 1
#define AC_EXECUTE 2
#define AC_MFUNCTION 3 /* not supported by busybox */
#define AC_CFUNCTION 4 /* not supported by busybox */
#define AC_COPY 5
#define AC_IGNORE 6
#define AC_MKOLDCOMPAT 7
#define AC_MKNEWCOMPAT 8
#define AC_RMOLDCOMPAT 9
#define AC_RMNEWCOMPAT 10
#define AC_RESTORE 11
struct permissions_type {
mode_t mode;
uid_t uid;
gid_t gid;
};
struct execute_type {
char *argv[MAX_ARGS + 1]; /* argv[0] must always be the programme */
};
struct copy_type {
const char *source;
const char *destination;
};
struct action_type {
unsigned int what;
unsigned int when;
};
struct config_entry_struct {
struct action_type action;
regex_t preg;
union
{
struct permissions_type permissions;
struct execute_type execute;
struct copy_type copy;
}
u;
struct config_entry_struct *next;
};
struct get_variable_info {
const struct devfsd_notify_struct *info;
const char *devname;
char devpath[STRING_LENGTH];
};
static void dir_operation(int , const char * , int, unsigned long*);
static void service(struct stat statbuf, char *path);
static int st_expr_expand(char *, unsigned, const char *, const char *(*)(const char *, void *), void *);
static const char *get_old_name(const char *, unsigned, char *, unsigned, unsigned);
static int mksymlink(const char *oldpath, const char *newpath);
static void read_config_file(char *path, int optional, unsigned long *event_mask);
static void process_config_line(const char *, unsigned long *);
static int do_servicing(int, unsigned long);
static void service_name(const struct devfsd_notify_struct *);
static void action_permissions(const struct devfsd_notify_struct *, const struct config_entry_struct *);
static void action_execute(const struct devfsd_notify_struct *, const struct config_entry_struct *,
const regmatch_t *, unsigned);
static void action_modload(const struct devfsd_notify_struct *info, const struct config_entry_struct *entry);
static void action_copy(const struct devfsd_notify_struct *, const struct config_entry_struct *,
const regmatch_t *, unsigned);
static void action_compat(const struct devfsd_notify_struct *, unsigned);
static void free_config(void);
static void restore(char *spath, struct stat source_stat, int rootlen);
static int copy_inode(const char *, const struct stat *, mode_t, const char *, const struct stat *);
static mode_t get_mode(const char *);
static void signal_handler(int);
static const char *get_variable(const char *, void *);
static int make_dir_tree(const char *);
static int expand_expression(char *, unsigned, const char *, const char *(*)(const char *, void *), void *,
const char *, const regmatch_t *, unsigned);
static void expand_regexp(char *, size_t, const char *, const char *, const regmatch_t *, unsigned);
static const char *expand_variable( char *, unsigned, unsigned *, const char *,
const char *(*)(const char *, void *), void *);
static const char *get_variable_v2(const char *, const char *(*)(const char *, void *), void *);
static char get_old_ide_name(unsigned, unsigned);
static char *write_old_sd_name(char *, unsigned, unsigned, const char *);
/* busybox functions */
static int get_uid_gid(int flag, const char *string);
static void safe_memcpy(char * dest, const char * src, int len);
static unsigned int scan_dev_name_common(const char *d, unsigned int n, int addendum, const char *ptr);
static unsigned int scan_dev_name(const char *d, unsigned int n, const char *ptr);
/* Structs and vars */
static struct config_entry_struct *first_config = NULL;
static struct config_entry_struct *last_config = NULL;
static char *mount_point = NULL;
static volatile int caught_signal = FALSE;
static volatile int caught_sighup = FALSE;
static struct initial_symlink_struct {
const char *dest;
const char *name;
} initial_symlinks[] = {
{"/proc/self/fd", "fd"},
{"fd/0", "stdin"},
{"fd/1", "stdout"},
{"fd/2", "stderr"},
{NULL, NULL},
};
static struct event_type {
unsigned int type; /* The DEVFSD_NOTIFY_* value */
const char *config_name; /* The name used in the config file */
} event_types[] = {
{DEVFSD_NOTIFY_REGISTERED, "REGISTER"},
{DEVFSD_NOTIFY_UNREGISTERED, "UNREGISTER"},
{DEVFSD_NOTIFY_ASYNC_OPEN, "ASYNC_OPEN"},
{DEVFSD_NOTIFY_CLOSE, "CLOSE"},
{DEVFSD_NOTIFY_LOOKUP, "LOOKUP"},
{DEVFSD_NOTIFY_CHANGE, "CHANGE"},
{DEVFSD_NOTIFY_CREATE, "CREATE"},
{DEVFSD_NOTIFY_DELETE, "DELETE"},
{0xffffffff, NULL}
};
/* Busybox messages */
static const char bb_msg_proto_rev[] ALIGN1 = "protocol revision";
static const char bb_msg_bad_config[] ALIGN1 = "bad %s config file: %s";
static const char bb_msg_small_buffer[] ALIGN1 = "buffer too small";
static const char bb_msg_variable_not_found[] ALIGN1 = "variable: %s not found";
/* Busybox stuff */
#if ENABLE_DEVFSD_VERBOSE || ENABLE_DEBUG
#define info_logger(p, fmt, args...) bb_info_msg(fmt, ## args)
#define simple_info_logger(p, msg) bb_simple_info_msg(msg)
#define msg_logger(p, fmt, args...) bb_error_msg(fmt, ## args)
#define simple_msg_logger(p, msg) bb_simple_error_msg(msg)
#define msg_logger_and_die(p, fmt, args...) bb_error_msg_and_die(fmt, ## args)
#define simple_msg_logger_and_die(p, msg) bb_simple_error_msg_and_die(msg)
#define error_logger(p, fmt, args...) bb_perror_msg(fmt, ## args)
#define error_logger_and_die(p, fmt, args...) bb_perror_msg_and_die(fmt, ## args)
#else
#define info_logger(p, fmt, args...)
#define simple_info_logger(p, msg)
#define msg_logger(p, fmt, args...)
#define simple_msg_logger(p, msg)
#define msg_logger_and_die(p, fmt, args...) exit_FAILURE()
#define simple_msg_logger_and_die(p, msg) exit_FAILURE()
#define error_logger(p, fmt, args...)
#define error_logger_and_die(p, fmt, args...) exit_FAILURE()
#endif
static void safe_memcpy(char *dest, const char *src, int len)
{
memcpy(dest, src, len);
dest[len] = '\0';
}
static unsigned int scan_dev_name_common(const char *d, unsigned int n, int addendum, const char *ptr)
{
if (d[n - 4] == 'd' && d[n - 3] == 'i' && d[n - 2] == 's' && d[n - 1] == 'c')
return 2 + addendum;
if (d[n - 2] == 'c' && d[n - 1] == 'd')
return 3 + addendum;
if (ptr[0] == 'p' && ptr[1] == 'a' && ptr[2] == 'r' && ptr[3] == 't')
return 4 + addendum;
if (ptr[n - 2] == 'm' && ptr[n - 1] == 't')
return 5 + addendum;
return 0;
}
static unsigned int scan_dev_name(const char *d, unsigned int n, const char *ptr)
{
if (d[0] == 's' && d[1] == 'c' && d[2] == 's' && d[3] == 'i' && d[4] == '/') {
if (d[n - 7] == 'g' && d[n - 6] == 'e' && d[n - 5] == 'n'
&& d[n - 4] == 'e' && d[n - 3] == 'r' && d[n - 2] == 'i' && d[n - 1] == 'c'
)
return 1;
return scan_dev_name_common(d, n, 0, ptr);
}
if (d[0] == 'i' && d[1] == 'd' && d[2] == 'e' && d[3] == '/'
&& d[4] == 'h' && d[5] == 'o' && d[6] == 's' && d[7] == 't'
)
return scan_dev_name_common(d, n, 4, ptr);
if (d[0] == 's' && d[1] == 'b' && d[2] == 'p' && d[3] == '/')
return 10;
if (d[0] == 'v' && d[1] == 'c' && d[2] == 'c' && d[3] == '/')
return 11;
if (d[0] == 'p' && d[1] == 't' && d[2] == 'y' && d[3] == '/')
return 12;
return 0;
}
/* Public functions follow */
int devfsd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int devfsd_main(int argc, char **argv)
{
int print_version = FALSE;
int do_daemon = TRUE;
int no_polling = FALSE;
int do_scan;
int fd, proto_rev, count;
unsigned long event_mask = 0;
struct sigaction new_action;
struct initial_symlink_struct *curr;
if (argc < 2)
bb_show_usage();
for (count = 2; count < argc; ++count) {
if (argv[count][0] == '-') {
if (argv[count][1] == 'v' && !argv[count][2]) /* -v */
print_version = TRUE;
else if (ENABLE_DEVFSD_FG_NP && argv[count][1] == 'f'
&& argv[count][2] == 'g' && !argv[count][3]) /* -fg */
do_daemon = FALSE;
else if (ENABLE_DEVFSD_FG_NP && argv[count][1] == 'n'
&& argv[count][2] == 'p' && !argv[count][3]) /* -np */
no_polling = TRUE;
else
bb_show_usage();
}
}
mount_point = bb_simplify_path(argv[1]);
xchdir(mount_point);
fd = xopen(".devfsd", O_RDONLY);
close_on_exec_on(fd);
xioctl(fd, DEVFSDIOC_GET_PROTO_REV, &proto_rev);
/*setup initial entries */
for (curr = initial_symlinks; curr->dest != NULL; ++curr)
symlink(curr->dest, curr->name);
/* NB: The check for CONFIG_FILE is done in read_config_file() */
if (print_version || (DEVFSD_PROTOCOL_REVISION_DAEMON != proto_rev)) {
printf("%s v%s\nDaemon %s:\t%d\nKernel-side %s:\t%d\n",
applet_name, DEVFSD_VERSION, bb_msg_proto_rev,
DEVFSD_PROTOCOL_REVISION_DAEMON, bb_msg_proto_rev, proto_rev);
if (DEVFSD_PROTOCOL_REVISION_DAEMON != proto_rev)
bb_error_msg_and_die("%s mismatch!", bb_msg_proto_rev);
exit_SUCCESS(); /* -v */
}
/* Tell kernel we are special(i.e. we get to see hidden entries) */
xioctl(fd, DEVFSDIOC_SET_EVENT_MASK, 0);
/* Set up SIGHUP and SIGUSR1 handlers */
sigemptyset(&new_action.sa_mask);
new_action.sa_flags = 0;
new_action.sa_handler = signal_handler;
sigaction_set(SIGHUP, &new_action);
sigaction_set(SIGUSR1, &new_action);
printf("%s v%s started for %s\n", applet_name, DEVFSD_VERSION, mount_point);
/* Set umask so that mknod(2), open(2) and mkdir(2) have complete control over permissions */
umask(0);
read_config_file((char*)CONFIG_FILE, FALSE, &event_mask);
/* Do the scan before forking, so that boot scripts see the finished product */
dir_operation(SERVICE, mount_point, 0, NULL);
if (ENABLE_DEVFSD_FG_NP && no_polling)
exit_SUCCESS();
if (ENABLE_DEVFSD_VERBOSE || ENABLE_DEBUG)
logmode = LOGMODE_BOTH;
else if (do_daemon == TRUE)
logmode = LOGMODE_SYSLOG;
/* This is the default */
/*else
logmode = LOGMODE_STDIO; */
if (do_daemon) {
/* Release so that the child can grab it */
xioctl(fd, DEVFSDIOC_RELEASE_EVENT_QUEUE, 0);
bb_daemonize_or_rexec(0, argv);
} else if (ENABLE_DEVFSD_FG_NP) {
setpgid(0, 0); /* Become process group leader */
}
while (TRUE) {
do_scan = do_servicing(fd, event_mask);
free_config();
read_config_file((char*)CONFIG_FILE, FALSE, &event_mask);
if (do_scan)
dir_operation(SERVICE, mount_point, 0, NULL);
}
if (ENABLE_FEATURE_CLEAN_UP) free(mount_point);
} /* End Function main */
/* Private functions follow */
static void read_config_file(char *path, int optional, unsigned long *event_mask)
/* [SUMMARY] Read a configuration database.
<path> The path to read the database from. If this is a directory, all
entries in that directory will be read(except hidden entries).
<optional> If TRUE, the routine will silently ignore a missing config file.
<event_mask> The event mask is written here. This is not initialised.
[RETURNS] Nothing.
*/
{
struct stat statbuf;
FILE *fp;
char buf[STRING_LENGTH];
char *line = NULL;
char *p;
if (stat(path, &statbuf) == 0) {
/* Don't read 0 length files: ignored */
/*if (statbuf.st_size == 0)
return;*/
if (S_ISDIR(statbuf.st_mode)) {
p = bb_simplify_path(path);
dir_operation(READ_CONFIG, p, 0, event_mask);
free(p);
return;
}
fp = fopen_for_read(path);
if (fp != NULL) {
while (fgets(buf, STRING_LENGTH, fp) != NULL) {
/* Skip whitespace */
line = buf;
line = skip_whitespace(line);
if (line[0] == '\0' || line[0] == '#')
continue;
process_config_line(line, event_mask);
}
fclose(fp);
} else {
goto read_config_file_err;
}
} else {
read_config_file_err:
if (optional == 0 && errno == ENOENT)
error_logger_and_die(LOG_ERR, "read config file: %s", path);
}
} /* End Function read_config_file */
static void process_config_line(const char *line, unsigned long *event_mask)
/* [SUMMARY] Process a line from a configuration file.
<line> The configuration line.
<event_mask> The event mask is written here. This is not initialised.
[RETURNS] Nothing.
*/
{
int num_args, count;
struct config_entry_struct *new;
char p[MAX_ARGS][STRING_LENGTH];
char when[STRING_LENGTH], what[STRING_LENGTH];
char name[STRING_LENGTH];
const char *msg = "";
char *ptr;
int i;
/* !!!! Only Uppercase Keywords in devsfd.conf */
static const char options[] ALIGN1 =
"CLEAR_CONFIG\0""INCLUDE\0""OPTIONAL_INCLUDE\0"
"RESTORE\0""PERMISSIONS\0""MODLOAD\0""EXECUTE\0"
"COPY\0""IGNORE\0""MKOLDCOMPAT\0""MKNEWCOMPAT\0"
"RMOLDCOMPAT\0""RMNEWCOMPAT\0";
for (count = 0; count < MAX_ARGS; ++count)
p[count][0] = '\0';
num_args = sscanf(line, "%s %s %s %s %s %s %s %s %s %s",
when, name, what,
p[0], p[1], p[2], p[3], p[4], p[5], p[6]);
i = index_in_strings(options, when);
/* "CLEAR_CONFIG" */
if (i == 0) {
free_config();
*event_mask = 0;
return;
}
if (num_args < 2)
goto process_config_line_err;
/* "INCLUDE" & "OPTIONAL_INCLUDE" */
if (i == 1 || i == 2) {
st_expr_expand(name, STRING_LENGTH, name, get_variable, NULL);
info_logger(LOG_INFO, "%sinclude: %s", (toupper(when[0]) == 'I') ? "": "optional_", name);
read_config_file(name, (toupper(when[0]) == 'I') ? FALSE : TRUE, event_mask);
return;
}
/* "RESTORE" */
if (i == 3) {
dir_operation(RESTORE, name, strlen(name),NULL);
return;
}
if (num_args < 3)
goto process_config_line_err;
new = xzalloc(sizeof *new);
for (count = 0; event_types[count].config_name != NULL; ++count) {
if (strcasecmp(when, event_types[count].config_name) != 0)
continue;
new->action.when = event_types[count].type;
break;
}
if (event_types[count].config_name == NULL) {
msg = "WHEN in";
goto process_config_line_err;
}
i = index_in_strings(options, what);
switch (i) {
case 4: /* "PERMISSIONS" */
new->action.what = AC_PERMISSIONS;
/* Get user and group */
ptr = strchr(p[0], '.');
if (ptr == NULL) {
msg = "UID.GID";
goto process_config_line_err; /*"missing '.' in UID.GID"*/
}
*ptr++ = '\0';
new->u.permissions.uid = get_uid_gid(UID, p[0]);
new->u.permissions.gid = get_uid_gid(GID, ptr);
/* Get mode */
new->u.permissions.mode = get_mode(p[1]);
break;
case 5: /* MODLOAD */
/*This action will pass "/dev/$devname"(i.e. "/dev/" prefixed to
the device name) to the module loading facility. In addition,
the /etc/modules.devfs configuration file is used.*/
if (ENABLE_DEVFSD_MODLOAD)
new->action.what = AC_MODLOAD;
break;
case 6: /* EXECUTE */
new->action.what = AC_EXECUTE;
num_args -= 3;
for (count = 0; count < num_args; ++count)
new->u.execute.argv[count] = xstrdup(p[count]);
new->u.execute.argv[num_args] = NULL;
break;
case 7: /* COPY */
new->action.what = AC_COPY;
num_args -= 3;
if (num_args != 2)
goto process_config_line_err; /* missing path and function in line */
new->u.copy.source = xstrdup(p[0]);
new->u.copy.destination = xstrdup(p[1]);
break;
case 8: /* IGNORE */
/* FALLTROUGH */
case 9: /* MKOLDCOMPAT */
/* FALLTROUGH */
case 10: /* MKNEWCOMPAT */
/* FALLTROUGH */
case 11:/* RMOLDCOMPAT */
/* FALLTROUGH */
case 12: /* RMNEWCOMPAT */
/* AC_IGNORE 6
AC_MKOLDCOMPAT 7
AC_MKNEWCOMPAT 8
AC_RMOLDCOMPAT 9
AC_RMNEWCOMPAT 10*/
new->action.what = i - 2;
break;
default:
msg = "WHAT in";
goto process_config_line_err;
/*esac*/
} /* switch (i) */
xregcomp(&new->preg, name, REG_EXTENDED);
*event_mask |= 1 << new->action.when;
new->next = NULL;
if (first_config == NULL)
first_config = new;
else
last_config->next = new;
last_config = new;
return;
process_config_line_err:
msg_logger_and_die(LOG_ERR, bb_msg_bad_config, msg, line);
} /* End Function process_config_line */
static int do_servicing(int fd, unsigned long event_mask)
/* [SUMMARY] Service devfs changes until a signal is received.
<fd> The open control file.
<event_mask> The event mask.
[RETURNS] TRUE if SIGHUP was caught, else FALSE.
*/
{
ssize_t bytes;
struct devfsd_notify_struct info;
/* (void*) cast is only in order to match prototype */
xioctl(fd, DEVFSDIOC_SET_EVENT_MASK, (void*)event_mask);
while (!caught_signal) {
errno = 0;
bytes = read(fd, (char *) &info, sizeof info);
if (caught_signal)
break; /* Must test for this first */
if (errno == EINTR)
continue; /* Yes, the order is important */
if (bytes < 1)
break;
service_name(&info);
}
if (caught_signal) {
int c_sighup = caught_sighup;
caught_signal = FALSE;
caught_sighup = FALSE;
return c_sighup;
}
simple_msg_logger_and_die(LOG_ERR, "read error on control file");
} /* End Function do_servicing */
static void service_name(const struct devfsd_notify_struct *info)
/* [SUMMARY] Service a single devfs change.
<info> The devfs change.
[RETURNS] Nothing.
*/
{
unsigned int n;
regmatch_t mbuf[MAX_SUBEXPR];
struct config_entry_struct *entry;
if (ENABLE_DEBUG && info->overrun_count > 0)
msg_logger(LOG_ERR, "lost %u events", info->overrun_count);
/* Discard lookups on "/dev/log" and "/dev/initctl" */
if (info->type == DEVFSD_NOTIFY_LOOKUP
&& ((info->devname[0] == 'l' && info->devname[1] == 'o'
&& info->devname[2] == 'g' && !info->devname[3])
|| (info->devname[0] == 'i' && info->devname[1] == 'n'
&& info->devname[2] == 'i' && info->devname[3] == 't'
&& info->devname[4] == 'c' && info->devname[5] == 't'
&& info->devname[6] == 'l' && !info->devname[7]))
)
return;
for (entry = first_config; entry != NULL; entry = entry->next) {
/* First check if action matches the type, then check if name matches */
if (info->type != entry->action.when
|| regexec(&entry->preg, info->devname, MAX_SUBEXPR, mbuf, 0) != 0)
continue;
for (n = 0;(n < MAX_SUBEXPR) && (mbuf[n].rm_so != -1); ++n)
/* VOID */;
switch (entry->action.what) {
case AC_PERMISSIONS:
action_permissions(info, entry);
break;
case AC_MODLOAD:
if (ENABLE_DEVFSD_MODLOAD)
action_modload(info, entry);
break;
case AC_EXECUTE:
action_execute(info, entry, mbuf, n);
break;
case AC_COPY:
action_copy(info, entry, mbuf, n);
break;
case AC_IGNORE:
return;
/*break;*/
case AC_MKOLDCOMPAT:
case AC_MKNEWCOMPAT:
case AC_RMOLDCOMPAT:
case AC_RMNEWCOMPAT:
action_compat(info, entry->action.what);
break;
default:
simple_msg_logger_and_die(LOG_ERR, "Unknown action");
}
}
} /* End Function service_name */
static void action_permissions(const struct devfsd_notify_struct *info,
const struct config_entry_struct *entry)
/* [SUMMARY] Update permissions for a device entry.
<info> The devfs change.
<entry> The config file entry.
[RETURNS] Nothing.
*/
{
struct stat statbuf;
if (stat(info->devname, &statbuf) != 0
|| chmod(info->devname, (statbuf.st_mode & S_IFMT) | (entry->u.permissions.mode & ~S_IFMT)) != 0
|| chown(info->devname, entry->u.permissions.uid, entry->u.permissions.gid) != 0
)
error_logger(LOG_ERR, "Can't chmod or chown: %s", info->devname);
} /* End Function action_permissions */
static void action_modload(const struct devfsd_notify_struct *info,
const struct config_entry_struct *entry UNUSED_PARAM)
/* [SUMMARY] Load a module.
<info> The devfs change.
<entry> The config file entry.
[RETURNS] Nothing.
*/
{
char *argv[6];
argv[0] = (char*)MODPROBE;
argv[1] = (char*)MODPROBE_SWITCH_1; /* "-k" */
argv[2] = (char*)MODPROBE_SWITCH_2; /* "-C" */
argv[3] = (char*)CONFIG_MODULES_DEVFS;
argv[4] = concat_path_file("/dev", info->devname); /* device */
argv[5] = NULL;
spawn_and_wait(argv);
free(argv[4]);
} /* End Function action_modload */
static void action_execute(const struct devfsd_notify_struct *info,
const struct config_entry_struct *entry,
const regmatch_t *regexpr, unsigned int numexpr)
/* [SUMMARY] Execute a programme.
<info> The devfs change.
<entry> The config file entry.
<regexpr> The number of subexpression(start, end) offsets within the
device name.
<numexpr> The number of elements within <<regexpr>>.
[RETURNS] Nothing.
*/
{
unsigned int count;
struct get_variable_info gv_info;
char *argv[MAX_ARGS + 1];
char largv[MAX_ARGS + 1][STRING_LENGTH];
gv_info.info = info;
gv_info.devname = info->devname;
snprintf(gv_info.devpath, sizeof(gv_info.devpath), "%s/%s", mount_point, info->devname);
for (count = 0; entry->u.execute.argv[count] != NULL; ++count) {
expand_expression(largv[count], STRING_LENGTH,
entry->u.execute.argv[count],
get_variable, &gv_info,
gv_info.devname, regexpr, numexpr);
argv[count] = largv[count];
}
argv[count] = NULL;
spawn_and_wait(argv);
} /* End Function action_execute */
static void action_copy(const struct devfsd_notify_struct *info,
const struct config_entry_struct *entry,
const regmatch_t *regexpr, unsigned int numexpr)
/* [SUMMARY] Copy permissions.
<info> The devfs change.
<entry> The config file entry.
<regexpr> This list of subexpression(start, end) offsets within the
device name.
<numexpr> The number of elements in <<regexpr>>.
[RETURNS] Nothing.
*/
{
mode_t new_mode;
struct get_variable_info gv_info;
struct stat source_stat, dest_stat;
char source[STRING_LENGTH], destination[STRING_LENGTH];
int ret = 0;
dest_stat.st_mode = 0;
if ((info->type == DEVFSD_NOTIFY_CHANGE) && S_ISLNK(info->mode))
return;
gv_info.info = info;
gv_info.devname = info->devname;
snprintf(gv_info.devpath, sizeof(gv_info.devpath), "%s/%s", mount_point, info->devname);
expand_expression(source, STRING_LENGTH, entry->u.copy.source,
get_variable, &gv_info, gv_info.devname,
regexpr, numexpr);
expand_expression(destination, STRING_LENGTH, entry->u.copy.destination,
get_variable, &gv_info, gv_info.devname,
regexpr, numexpr);
if (!make_dir_tree(destination) || lstat(source, &source_stat) != 0)
return;
lstat(destination, &dest_stat);
new_mode = source_stat.st_mode & ~S_ISVTX;
if (info->type == DEVFSD_NOTIFY_CREATE)
new_mode |= S_ISVTX;
else if ((info->type == DEVFSD_NOTIFY_CHANGE) &&(dest_stat.st_mode & S_ISVTX))
new_mode |= S_ISVTX;
ret = copy_inode(destination, &dest_stat, new_mode, source, &source_stat);
if (ENABLE_DEBUG && ret && (errno != EEXIST))
error_logger(LOG_ERR, "copy_inode: %s to %s", source, destination);
} /* End Function action_copy */
static void action_compat(const struct devfsd_notify_struct *info, unsigned int action)
/* [SUMMARY] Process a compatibility request.
<info> The devfs change.
<action> The action to take.
[RETURNS] Nothing.
*/
{
int ret;
const char *compat_name = NULL;
const char *dest_name = info->devname;
const char *ptr;
char compat_buf[STRING_LENGTH], dest_buf[STRING_LENGTH];
int mode, host, bus, target, lun;
unsigned int i;
char rewind_;
/* 1 to 5 "scsi/" , 6 to 9 "ide/host" */
static const char *const fmt[] ALIGN_PTR = {
NULL ,
"sg/c%db%dt%du%d", /* scsi/generic */
"sd/c%db%dt%du%d", /* scsi/disc */
"sr/c%db%dt%du%d", /* scsi/cd */
"sd/c%db%dt%du%dp%d", /* scsi/part */
"st/c%db%dt%du%dm%d%c", /* scsi/mt */
"ide/hd/c%db%dt%du%d", /* ide/host/disc */
"ide/cd/c%db%dt%du%d", /* ide/host/cd */
"ide/hd/c%db%dt%du%dp%d", /* ide/host/part */
"ide/mt/c%db%dt%du%d%s", /* ide/host/mt */
NULL
};
/* First construct compatibility name */
switch (action) {
case AC_MKOLDCOMPAT:
case AC_RMOLDCOMPAT:
compat_name = get_old_name(info->devname, info->namelen, compat_buf, info->major, info->minor);
break;
case AC_MKNEWCOMPAT:
case AC_RMNEWCOMPAT:
ptr = bb_basename(info->devname);
i = scan_dev_name(info->devname, info->namelen, ptr);
/* nothing found */
if (i == 0 || i > 9)
return;
sscanf(info->devname + ((i < 6) ? 5 : 4), "host%d/bus%d/target%d/lun%d/", &host, &bus, &target, &lun);
snprintf(dest_buf, sizeof(dest_buf), "../%s", info->devname + (( i > 5) ? 4 : 0));
dest_name = dest_buf;
compat_name = compat_buf;
/* 1 == scsi/generic 2 == scsi/disc 3 == scsi/cd 6 == ide/host/disc 7 == ide/host/cd */
if (i == 1 || i == 2 || i == 3 || i == 6 || i ==7)
sprintf(compat_buf, fmt[i], host, bus, target, lun);
/* 4 == scsi/part 8 == ide/host/part */
if (i == 4 || i == 8)
sprintf(compat_buf, fmt[i], host, bus, target, lun, atoi(ptr + 4));
/* 5 == scsi/mt */
if (i == 5) {
rewind_ = info->devname[info->namelen - 1];
if (rewind_ != 'n')
rewind_ = '\0';
mode = 0;
if (ptr[2] == 'l' /*108*/ || ptr[2] == 'm'/*109*/)
mode = ptr[2] - 107; /* 1 or 2 */
if (ptr[2] == 'a')
mode = 3;
sprintf(compat_buf, fmt[i], host, bus, target, lun, mode, rewind_);
}
/* 9 == ide/host/mt */
if (i == 9)
snprintf(compat_buf, sizeof(compat_buf), fmt[i], host, bus, target, lun, ptr + 2);
/* esac */
} /* switch (action) */
if (compat_name == NULL)
return;
/* Now decide what to do with it */
switch (action) {
case AC_MKOLDCOMPAT:
case AC_MKNEWCOMPAT:
mksymlink(dest_name, compat_name);