namedev.c revision 50e5de03d16be3e35e65cdf65f552807ad24e996
/*
* namedev.c
*
* Userspace devfs
*
* Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
*
*
* 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 version 2 of the License.
*
* 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.
*
*/
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <fcntl.h>
#include <ctype.h>
#include <unistd.h>
#include <errno.h>
#include <time.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include "list.h"
#include "udev.h"
#include "udev_version.h"
#include "logging.h"
#include "namedev.h"
#include "libsysfs/libsysfs.h"
#include "klibc_fixups.h"
static struct sysfs_attribute *find_sysfs_attribute(struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device, char *attr);
LIST_HEAD(config_device_list);
LIST_HEAD(perm_device_list);
/* compare string with pattern (supports * ? [0-9] [!A-Z]) */
static int strcmp_pattern(const char *p, const char *s)
{
if (s[0] == '\0') {
while (p[0] == '*')
p++;
return (p[0] != '\0');
}
switch (p[0]) {
case '[':
{
int not = 0;
p++;
if (p[0] == '!') {
not = 1;
p++;
}
while ((p[0] != '\0') && (p[0] != ']')) {
int match = 0;
if (p[1] == '-') {
if ((s[0] >= p[0]) && (s[0] <= p[2]))
match = 1;
p += 3;
} else {
match = (p[0] == s[0]);
p++;
}
if (match ^ not) {
while ((p[0] != '\0') && (p[0] != ']'))
p++;
if (p[0] == ']')
return strcmp_pattern(p+1, s+1);
}
}
}
break;
case '*':
if (strcmp_pattern(p, s+1))
return strcmp_pattern(p+1, s);
return 0;
case '\0':
if (s[0] == '\0') {
return 0;
}
break;
default:
if ((p[0] == s[0]) || (p[0] == '?'))
return strcmp_pattern(p+1, s+1);
break;
}
return 1;
}
#define copy_var(a, b, var) \
if (b->var) \
a->var = b->var;
#define copy_string(a, b, var) \
if (strlen(b->var)) \
strcpy(a->var, b->var);
int add_perm_dev(struct perm_device *new_dev)
{
struct perm_device *dev;
struct perm_device *tmp_dev;
/* update the values if we already have the device */
list_for_each_entry(dev, &perm_device_list, node) {
if (strcmp(new_dev->name, dev->name))
continue;
copy_var(dev, new_dev, mode);
copy_string(dev, new_dev, owner);
copy_string(dev, new_dev, group);
return 0;
}
/* not found, add new structure to the perm list */
tmp_dev = malloc(sizeof(*tmp_dev));
if (!tmp_dev)
return -ENOMEM;
memcpy(tmp_dev, new_dev, sizeof(*tmp_dev));
list_add_tail(&tmp_dev->node, &perm_device_list);
//dump_perm_dev(tmp_dev);
return 0;
}
static struct perm_device *find_perm(char *name)
{
struct perm_device *perm;
list_for_each_entry(perm, &perm_device_list, node) {
if (strcmp_pattern(perm->name, name))
continue;
return perm;
}
return NULL;
}
static mode_t get_default_mode(void)
{
mode_t mode = 0600; /* default to owner rw only */
if (strlen(default_mode_str) != 0)
mode = strtol(default_mode_str, NULL, 8);
return mode;
}
static char *get_default_owner(void)
{
if (strlen(default_owner_str) == 0)
strncpy(default_owner_str, "root", OWNER_SIZE);
return default_owner_str;
}
static char *get_default_group(void)
{
if (strlen(default_group_str) == 0)
strncpy(default_group_str, "root", GROUP_SIZE);
return default_group_str;
}
/* extract possible {attr} and move str behind it */
static char *get_format_attribute(char **str)
{
char *pos;
char *attr = NULL;
if (*str[0] == '{') {
pos = strchr(*str, '}');
if (pos == NULL) {
dbg("missing closing brace for format");
return NULL;
}
pos[0] = '\0';
attr = *str+1;
*str = pos+1;
dbg("attribute='%s', str='%s'", attr, *str);
}
return attr;
}
/* extract possible format length and move str behind it*/
static int get_format_len(char **str)
{
int num;
char *tail;
if (isdigit(*str[0])) {
num = (int) strtoul(*str, &tail, 10);
if (tail != NULL) {
*str = tail;
dbg("format length=%i", num);
return num;
} else {
dbg("format parsing error '%s'", *str);
}
}
return -1;
}
static void apply_format(struct udevice *udev, unsigned char *string, struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device)
{
char temp[NAME_SIZE];
char temp1[NAME_SIZE];
char *tail;
char *pos;
char *pos2;
char *pos3;
char *attr;
int num;
char c;
struct sysfs_attribute *tmpattr;
pos = string;
while (1) {
pos = strchr(pos, '%');
if (pos != NULL) {
pos[0] = '\0';
tail = pos+1;
num = get_format_len(&tail);
c = tail[0];
strfieldcpy(temp, tail+1);
tail = temp;
} else {
break;
}
dbg("format=%c, string='%s', tail='%s'",c , string, tail);
attr = get_format_attribute(&tail);
switch (c) {
case 'b':
if (strlen(udev->bus_id) == 0)
break;
strcat(pos, udev->bus_id);
dbg("substitute bus_id '%s'", udev->bus_id);
break;
case 'k':
if (strlen(udev->kernel_name) == 0)
break;
strcat(pos, udev->kernel_name);
dbg("substitute kernel name '%s'", udev->kernel_name);
break;
case 'n':
if (strlen(udev->kernel_number) == 0)
break;
strcat(pos, udev->kernel_number);
dbg("substitute kernel number '%s'", udev->kernel_number);
break;
case 'm':
sprintf(pos, "%u", udev->minor);
dbg("substitute minor number '%u'", udev->minor);
break;
case 'M':
sprintf(pos, "%u", udev->major);
dbg("substitute major number '%u'", udev->major);
break;
case 'c':
if (strlen(udev->program_result) == 0)
break;
if (num > 0) {
strncpy(temp1, udev->program_result, sizeof(temp1));
pos2 = temp1;
while (num) {
num--;
pos3 = strsep(&pos2, " ");
if (pos3 == NULL) {
dbg("requested part of result string not found");
break;
}
}
if (pos3) {
strcat(pos, pos3);
dbg("substitute part of result string '%s'", pos3);
}
} else {
strcat(pos, udev->program_result);
dbg("substitute result string '%s'", udev->program_result);
}
break;
case 's':
if (attr != NULL) {
tmpattr = find_sysfs_attribute(class_dev, sysfs_device, attr);
if (tmpattr == NULL) {
dbg("sysfa attribute '%s' not found", attr);
break;
}
strcpy(pos, tmpattr->value);
dbg("substitute sysfs value '%s'", tmpattr->value);
} else {
dbg("missing attribute");
}
break;
case '%':
strcat(pos, "%");
break;
default:
dbg("unknown substitution type '%%%c'", c);
break;
}
strcat(pos, tail);
}
}
/*
* Note, we can have multiple files for different busses in here due
* to the mess that USB has for its device tree...
*/
static struct bus_file {
char *bus;
char *file;
} bus_files[] = {
{ .bus = "scsi", .file = "vendor" },
{ .bus = "usb", .file = "idVendor" },
{ .bus = "usb", .file = "iInterface" },
{ .bus = "usb-serial", .file = "detach_state" },
{ .bus = "ide", .file = "detach_state" },
{ .bus = "pci", .file = "vendor" },
{}
};
#define SECONDS_TO_WAIT_FOR_FILE 10
static void wait_for_device_to_initialize(struct sysfs_device *sysfs_device)
{
/* sleep until we see the file for this specific bus type show up this
* is needed because we can easily out-run the kernel in looking for
* these files before the paticular subsystem has created them in the
* sysfs tree properly.
*
* And people thought that the /sbin/hotplug event system was going to
* be slow, poo on you for arguing that before even testing it...
*/
struct bus_file *b = &bus_files[0];
struct sysfs_attribute *tmpattr;
int found = 0;
int loop = SECONDS_TO_WAIT_FOR_FILE;
while (1) {
if (b->bus == NULL) {
if (!found)
break;
/* sleep to give the kernel a chance to create the file */
sleep(1);
--loop;
if (loop == 0)
break;
b = &bus_files[0];
}
if (strcmp(sysfs_device->bus, b->bus) == 0) {
found = 1;
dbg("looking for file '%s' on bus '%s'", b->file, b->bus);
tmpattr = sysfs_get_device_attr(sysfs_device, b->file);
if (tmpattr) {
/* found it! */
goto exit;
}
dbg("can't find '%s' file", b->file);
}
++b;
}
if (!found)
dbg("did not find bus type '%s' on list of bus_id_files, "
"contact greg@kroah.com", sysfs_device->bus);
exit:
return; /* here to prevent compiler warning... */
}
static void fix_kernel_name(struct udevice *udev)
{
char *temp = udev->kernel_name;
while (*temp != 0x00) {
/* Some block devices have a ! in their name,
* we need to change that to / */
if (*temp == '!')
*temp = '/';
++temp;
}
}
static int execute_program(char *path, char *value, int len)
{
int retval;
int res;
int status;
int fds[2];
pid_t pid;
int value_set = 0;
char buffer[256];
char *pos;
char *args[PROGRAM_MAXARG];
int i;
dbg("executing '%s'", path);
retval = pipe(fds);
if (retval != 0) {
dbg("pipe failed");
return -1;
}
pid = fork();
switch(pid) {
case 0:
/* child */
close(STDOUT_FILENO);
dup(fds[1]); /* dup write side of pipe to STDOUT */
if (strchr(path, ' ')) {
/* exec with arguments */
pos = path;
for (i=0; i < PROGRAM_MAXARG-1; i++) {
args[i] = strsep(&pos, " ");
if (args[i] == NULL)
break;
}
if (args[i]) {
dbg("too many args - %d", i);
args[i] = NULL;
}
retval = execv(args[0], args);
} else {
retval = execv(path, main_argv);
}
dbg("child execve failed");
exit(1);
case -1:
dbg("fork failed");
return -1;
default:
/* parent reads from fds[0] */
close(fds[1]);
retval = 0;
while (1) {
res = read(fds[0], buffer, sizeof(buffer) - 1);
if (res <= 0)
break;
buffer[res] = '\0';
if (res > len) {
dbg("result len %d too short", len);
retval = -1;
}
if (value_set) {
dbg("result value already set");
retval = -1;
} else {
value_set = 1;
strncpy(value, buffer, len);
pos = value + strlen(value)-1;
if (pos[0] == '\n')
pos[0] = '\0';
dbg("result is '%s'", value);
}
}
close(fds[0]);
res = wait(&status);
if (res < 0) {
dbg("wait failed result %d", res);
retval = -1;
}
if (!WIFEXITED(status) || (WEXITSTATUS(status) != 0)) {
dbg("exec program status 0x%x", status);
retval = -1;
}
}
return retval;
}
static struct sysfs_attribute *find_sysfs_attribute(struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device, char *attr)
{
struct sysfs_attribute *tmpattr = NULL;
char *c;
dbg("look for device attribute '%s'", attr);
/* try to find the attribute in the class device directory */
tmpattr = sysfs_get_classdev_attr(class_dev, attr);
if (tmpattr)
goto attr_found;
/* look in the class device directory if present */
if (sysfs_device) {
tmpattr = sysfs_get_device_attr(sysfs_device, attr);
if (tmpattr)
goto attr_found;
}
return NULL;
attr_found:
c = strchr(tmpattr->value, '\n');
if (c != NULL)
c[0] = '\0';
dbg("found attribute '%s'", tmpattr->path);
return tmpattr;
}
static int compare_sysfs_attribute(struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device, struct sysfs_pair *pair)
{
struct sysfs_attribute *tmpattr;
if ((pair == NULL) || (pair->file[0] == '\0') || (pair->value == '\0'))
return -ENODEV;
tmpattr = find_sysfs_attribute(class_dev, sysfs_device, pair->file);
if (tmpattr == NULL)
return -ENODEV;
dbg("compare attribute '%s' value '%s' with '%s'",
pair->file, tmpattr->value, pair->value);
if (strcmp_pattern(pair->value, tmpattr->value) != 0)
return -ENODEV;
dbg("found matching attribute '%s' with value '%s'",
pair->file, pair->value);
return 0;
}
static int match_sysfs_pairs(struct config_device *dev, struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device)
{
struct sysfs_pair *pair;
int i;
for (i = 0; i < MAX_SYSFS_PAIRS; ++i) {
pair = &dev->sysfs_pair[i];
if ((pair->file[0] == '\0') || (pair->value[0] == '\0'))
break;
if (compare_sysfs_attribute(class_dev, sysfs_device, pair) != 0) {
dbg("sysfs attribute doesn't match");
return -ENODEV;
}
}
return 0;
}
static int match_id(struct config_device *dev, struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device)
{
char path[SYSFS_PATH_MAX];
char *temp = NULL;
/* we have to have a sysfs device for ID to work */
if (!sysfs_device)
return -ENODEV;
strfieldcpy(path, sysfs_device->path);
temp = strrchr(path, '/');
temp++;
dbg("search '%s' in '%s', path='%s'", dev->id, temp, path);
if (strcmp_pattern(dev->id, temp) != 0)
return -ENODEV;
else
return 0;
}
static int match_place(struct config_device *dev, struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device)
{
char path[SYSFS_PATH_MAX];
int found;
char *temp = NULL;
/* we have to have a sysfs device for PLACE to work */
if (!sysfs_device)
return -ENODEV;
found = 0;
strfieldcpy(path, sysfs_device->path);
temp = strrchr(path, '/');
dbg("search '%s' in '%s', path='%s'", dev->place, temp, path);
if (strstr(temp, dev->place) != NULL) {
found = 1;
} else {
*temp = 0x00;
temp = strrchr(path, '/');
dbg("search '%s' in '%s', path='%s'", dev->place, temp, path);
if (strstr(temp, dev->place) != NULL)
found = 1;
}
if (!found) {
dbg("place doesn't match");
return -ENODEV;
}
return 0;
}
static struct sysfs_device *get_sysfs_device(struct sysfs_class_device *class_dev)
{
struct sysfs_device *sysfs_device;
struct sysfs_class_device *class_dev_parent;
struct timespec tspec;
int loop;
/* Figure out where the device symlink is at. For char devices this will
* always be in the class_dev->path. But for block devices, it's different.
* The main block device will have the device symlink in it's path, but
* all partitions have the symlink in its parent directory.
* But we need to watch out for block devices that do not have parents, yet
* look like a partition (fd0, loop0, etc.) They all do not have a device
* symlink yet. We do sit and spin on waiting for them right now, we should
* possibly have a whitelist for these devices here...
*/
class_dev_parent = sysfs_get_classdev_parent(class_dev);
if (class_dev_parent)
dbg("Really a partition");
tspec.tv_sec = 0;
tspec.tv_nsec = 10000000; /* sleep 10 millisec */
loop = 10;
while (loop--) {
nanosleep(&tspec, NULL);
if (class_dev_parent)
sysfs_device = sysfs_get_classdev_device(class_dev_parent);
else
sysfs_device = sysfs_get_classdev_device(class_dev);
if (sysfs_device != NULL)
goto device_found;
}
dbg("timed out waiting for device symlink, continuing on anyway...");
device_found:
/* We have another issue with just the wait above - the sysfs part of
* the kernel may not be quick enough to have created the link to the
* device under the "bus" subsystem. Due to this, the sysfs_device->bus
* will not contain the actual bus name :(
*
* Libsysfs now provides a new API sysfs_get_device_bus(), so use it
* if needed
*/
if (sysfs_device) {
if (sysfs_device->bus[0] != '\0')
goto bus_found;
loop = 10;
tspec.tv_nsec = 10000000;
while (loop--) {
nanosleep(&tspec, NULL);
sysfs_get_device_bus(sysfs_device);
if (sysfs_device->bus[0] != '\0')
goto bus_found;
}
dbg("timed out waiting to find the device bus, continuing on anyway");
goto exit;
bus_found:
dbg("device %s is registered with bus '%s'",
sysfs_device->name, sysfs_device->bus);
}
exit:
return sysfs_device;
}
static int match_rule(struct config_device *dev, struct sysfs_class_device *class_dev, struct udevice *udev, struct sysfs_device *sysfs_device)
{
while (1) {
/* check for matching bus value */
if (dev->bus[0] != '\0') {
if (sysfs_device == NULL) {
dbg("device has no bus");
goto try_parent;
}
dbg("check for " FIELD_BUS " dev->bus='%s' sysfs_device->bus='%s'", dev->bus, sysfs_device->bus);
if (strcmp_pattern(dev->bus, sysfs_device->bus) != 0) {
dbg(FIELD_BUS " is not matching");
goto try_parent;
} else {
dbg(FIELD_BUS " matches");
}
}
/* check for matching kernel name*/
if (dev->kernel[0] != '\0') {
dbg("check for " FIELD_KERNEL " dev->kernel='%s' class_dev->name='%s'", dev->kernel, class_dev->name);
if (strcmp_pattern(dev->kernel, class_dev->name) != 0) {
dbg(FIELD_KERNEL " is not matching");
goto try_parent;
} else {
dbg(FIELD_KERNEL " matches");
}
}
/* check for matching bus id */
if (dev->id[0] != '\0') {
dbg("check " FIELD_ID);
if (match_id(dev, class_dev, sysfs_device) != 0) {
dbg(FIELD_ID " is not matching");
goto try_parent;
} else {
dbg(FIELD_ID " matches");
}
}
/* check for matching place of device */
if (dev->place[0] != '\0') {
dbg("check " FIELD_PLACE);
if (match_place(dev, class_dev, sysfs_device) != 0) {
dbg(FIELD_PLACE " is not matching");
goto try_parent;
} else {
dbg(FIELD_PLACE " matches");
}
}
/* check for matching sysfs pairs */
if (dev->sysfs_pair[0].file[0] != '\0') {
dbg("check " FIELD_SYSFS " pairs");
if (match_sysfs_pairs(dev, class_dev, sysfs_device) != 0) {
dbg(FIELD_SYSFS " is not matching");
goto try_parent;
} else {
dbg(FIELD_SYSFS " matches");
}
}
/* execute external program */
if (dev->program[0] != '\0') {
dbg("check " FIELD_PROGRAM);
apply_format(udev, dev->program, class_dev, sysfs_device);
if (execute_program(dev->program, udev->program_result, NAME_SIZE) != 0) {
dbg(FIELD_PROGRAM " returned nozero");
goto try_parent;
} else {
dbg(FIELD_PROGRAM " returned successful");
}
}
/* check for matching result of external program */
if (dev->result[0] != '\0') {
dbg("check for " FIELD_RESULT
" dev->result='%s', udev->program_result='%s'",
dev->result, udev->program_result);
if (strcmp_pattern(dev->result, udev->program_result) != 0) {
dbg(FIELD_RESULT " is not matching");
goto try_parent;
} else {
dbg(FIELD_RESULT " matches");
}
}
/* Yeah, we matched! */
return 0;
try_parent:
dbg("try parent sysfs device");
sysfs_device = sysfs_get_device_parent(sysfs_device);
if (sysfs_device == NULL)
return -ENODEV;
dbg("sysfs_device->path='%s'", sysfs_device->path);
dbg("sysfs_device->bus_id='%s'", sysfs_device->bus_id);
dbg("sysfs_device->bus='%s'", sysfs_device->bus);
}
}
int namedev_name_device(struct sysfs_class_device *class_dev, struct udevice *udev)
{
struct sysfs_device *sysfs_device = NULL;
struct config_device *dev;
struct perm_device *perm;
char *pos;
udev->mode = 0;
/* find the sysfs_device associated with this class device */
sysfs_device = get_sysfs_device(class_dev);
if (sysfs_device) {
dbg("sysfs_device->path='%s'", sysfs_device->path);
dbg("sysfs_device->bus_id='%s'", sysfs_device->bus_id);
dbg("sysfs_device->bus='%s'", sysfs_device->bus);
strfieldcpy(udev->bus_id, sysfs_device->bus_id);
wait_for_device_to_initialize(sysfs_device);
}
dbg("class_dev->name = '%s'", class_dev->name);
strfieldcpy(udev->kernel_name, class_dev->name);
fix_kernel_name(udev);
dbg("udev->kernel_name = '%s'", udev->kernel_name);
/* get kernel number */
pos = class_dev->name + strlen(class_dev->name);
while (isdigit(*(pos-1)))
pos--;
strfieldcpy(udev->kernel_number, pos);
dbg("kernel_number='%s'", udev->kernel_number);
/* look for a matching rule to apply */
list_for_each_entry(dev, &config_device_list, node) {
dbg("process rule");
if (match_rule(dev, class_dev, udev, sysfs_device) == 0) {
if (dev->name[0] == '\0') {
info("configured rule in '%s' at line %i applied, '%s' is ignored",
udev_rules_filename, dev->config_line, udev->kernel_name);
return -1;
}
info("configured rule in '%s' at line %i applied, '%s' becomes '%s'",
udev_rules_filename, dev->config_line, udev->kernel_name, dev->name);
strfieldcpy(udev->name, dev->name);
strfieldcpy(udev->symlink, dev->symlink);
goto found;
}
}
/* no rule was found so we use the kernel name */
strfieldcpy(udev->name, udev->kernel_name);
goto done;
found:
/* substitute placeholder */
apply_format(udev, udev->name, class_dev, sysfs_device);
apply_format(udev, udev->symlink, class_dev, sysfs_device);
udev->partitions = dev->partitions;
done:
perm = find_perm(udev->name);
if (perm) {
udev->mode = perm->mode;
strfieldcpy(udev->owner, perm->owner);
strfieldcpy(udev->group, perm->group);
} else {
/* no matching perms found :( */
udev->mode = get_default_mode();
strncpy(udev->owner, get_default_owner(), OWNER_SIZE);
strncpy(udev->group, get_default_group(), GROUP_SIZE);
}
dbg("name, '%s' is going to have owner='%s', group='%s', mode = %#o",
udev->name, udev->owner, udev->group, udev->mode);
return 0;
}
int namedev_init(void)
{
int retval;
retval = namedev_init_rules();
if (retval)
return retval;
retval = namedev_init_permissions();
if (retval)
return retval;
dump_config_dev_list();
dump_perm_dev_list();
return retval;
}