-/* vi:set ts=4:
- *
+/* vi: set sw=4 ts=4: */
+/*
+ *
* mdev - Mini udev for busybox
- *
+ *
* Copyright 2005 Rob Landley <rob@landley.net>
* Copyright 2005 Frank Sorenson <frank@tuxrocks.com>
*
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPL version 2, see file LICENSE in this tarball for details.
*/
-#include <dirent.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <stdio.h>
-#include <string.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-#include <unistd.h>
+#include "busybox.h"
+#include "xregex.h"
#define DEV_PATH "/dev"
-#define DEV_MODE 0660
-#include <busybox.h>
+struct mdev_globals
+{
+ int root_major, root_minor;
+} mdev_globals;
+
+#define bbg mdev_globals
/* mknod in /dev based on a path like "/sys/block/hda/hda1" */
-void make_device(char *path)
+static void make_device(char *path, int delete)
{
- char *device_name, *s;
- int major,minor,type,len,fd;
+ char *device_name;
+ int major, minor, type, len;
+ int mode = 0660;
+ uid_t uid = 0;
+ gid_t gid = 0;
+ char *temp = path + strlen(path);
+ char *command = NULL;
- RESERVE_CONFIG_BUFFER(temp,PATH_MAX);
+ /* Try to read major/minor string. Note that the kernel puts \n after
+ * the data, so we don't need to worry about null terminating the string
+ * because sscanf() will stop at the first nondigit, which \n is. We
+ * also depend on path having writeable space after it. */
+
+ if (!delete) {
+ strcat(path, "/dev");
+ len = open_read_close(path, temp + 1, 64);
+ *temp++ = 0;
+ if (len < 1) return;
+ }
- /* Try to read major/minor string */
-
- snprintf(temp, PATH_MAX, "%s/dev", path);
- fd = open(temp, O_RDONLY);
- len = read(fd, temp, PATH_MAX-1);
- if (len<1) goto end;
- temp[len] = 0;
- close(fd);
-
/* Determine device name, type, major and minor */
-
+
device_name = strrchr(path, '/') + 1;
- type = strncmp(path+5, "block/" ,6) ? S_IFCHR : S_IFBLK;
- major = minor = 0;
- for(s = temp; *s; s++) {
- if(*s == ':') {
- major = minor;
- minor = 0;
- } else {
- minor *= 10;
- minor += (*s) - '0';
+ type = path[5]=='c' ? S_IFCHR : S_IFBLK;
+
+ /* If we have a config file, look up permissions for this device */
+
+ if (ENABLE_FEATURE_MDEV_CONF) {
+ char *conf, *pos, *end;
+ int line, fd;
+
+ /* mmap the config file */
+ fd = open("/etc/mdev.conf", O_RDONLY);
+ if (fd < 0)
+ goto end_parse;
+ len = xlseek(fd, 0, SEEK_END);
+ conf = mmap(NULL, len, PROT_READ, MAP_PRIVATE, fd, 0);
+ close(fd);
+ if (!conf)
+ goto end_parse;
+
+ line = 0;
+ /* Loop through lines in mmaped file*/
+ for (pos=conf; pos-conf<len;) {
+ int field;
+ char *end2;
+
+ line++;
+ /* find end of this line */
+ for (end=pos; end-conf<len && *end!='\n'; end++)
+ ;
+
+ /* Three fields: regex, uid:gid, mode */
+ for (field=0; field < (3 + ENABLE_FEATURE_MDEV_EXEC);
+ field++)
+ {
+ /* Skip whitespace */
+ while (pos<end && isspace(*pos)) pos++;
+ if (pos==end || *pos=='#') break;
+ for (end2=pos;
+ end2<end && !isspace(*end2) && *end2!='#'; end2++)
+ ;
+
+ if (field == 0) {
+ /* Regex to match this device */
+
+ char *regex = strndupa(pos, end2-pos);
+ regex_t match;
+ regmatch_t off;
+ int result;
+
+ /* Is this it? */
+ xregcomp(&match,regex, REG_EXTENDED);
+ result = regexec(&match, device_name, 1, &off, 0);
+ regfree(&match);
+
+ /* If not this device, skip rest of line */
+ if (result || off.rm_so
+ || off.rm_eo != strlen(device_name))
+ break;
+ }
+ if (field == 1) {
+ /* uid:gid */
+
+ char *s, *s2;
+
+ /* Find : */
+ for (s=pos; s<end2 && *s!=':'; s++)
+ ;
+ if (s == end2) break;
+
+ /* Parse UID */
+ uid = strtoul(pos, &s2, 10);
+ if (s != s2) {
+ struct passwd *pass;
+ pass = getpwnam(strndupa(pos, s-pos));
+ if (!pass) break;
+ uid = pass->pw_uid;
+ }
+ s++;
+ /* parse GID */
+ gid = strtoul(s, &s2, 10);
+ if (end2 != s2) {
+ struct group *grp;
+ grp = getgrnam(strndupa(s, end2-s));
+ if (!grp) break;
+ gid = grp->gr_gid;
+ }
+ }
+ if (field == 2) {
+ /* mode */
+
+ mode = strtoul(pos, &pos, 8);
+ if (pos != end2) break;
+ }
+ if (ENABLE_FEATURE_MDEV_EXEC && field == 3) {
+ // Command to run
+ const char *s = "@$*";
+ const char *s2;
+ s2 = strchr(s, *pos++);
+ if (!s2) {
+ // Force error
+ field = 1;
+ break;
+ }
+ if ((s2-s+1) & (1<<delete))
+ command = xstrndup(pos, end-pos);
+ }
+
+ pos = end2;
+ }
+
+ /* Did everything parse happily? */
+
+ if (field > 2) break;
+ if (field) bb_error_msg_and_die("bad line %d",line);
+
+ /* Next line */
+ pos = ++end;
}
+ munmap(conf, len);
+ end_parse: /* nothing */ ;
}
-/* Open config file here, look up permissions */
+ umask(0);
+ if (!delete) {
+ if (sscanf(temp, "%d:%d", &major, &minor) != 2) return;
+ if (mknod(device_name, mode | type, makedev(major, minor)) && errno != EEXIST)
+ bb_perror_msg_and_die("mknod %s", device_name);
+
+ if (major == bbg.root_major && minor == bbg.root_minor)
+ symlink(device_name, "root");
- sprintf(temp, "%s/%s", DEV_PATH, device_name);
- if(mknod(temp, DEV_MODE | type, makedev(major, minor)) && errno != EEXIST)
- bb_perror_msg_and_die("mknod %s failed", temp);
-
-/* Perform shellout here */
+ if (ENABLE_FEATURE_MDEV_CONF) chown(device_name, uid, gid);
+ }
+ if (command) {
+ int rc;
+ char *s;
-end:
- RELEASE_CONFIG_BUFFER(temp);
+ s = xasprintf("MDEV=%s", device_name);
+ putenv(s);
+ rc = system(command);
+ s[4] = 0;
+ putenv(s);
+ free(s);
+ free(command);
+ if (rc == -1) bb_perror_msg_and_die("cannot run %s", command);
+ }
+ if (delete) unlink(device_name);
}
/* Recursive search of /sys/block or /sys/class. path must be a writeable
* buffer of size PATH_MAX containing the directory string to start at. */
-void find_dev(char *path)
+static void find_dev(char *path)
{
DIR *dir;
- int len=strlen(path);
+ size_t len = strlen(path);
+ struct dirent *entry;
- if(!(dir = opendir(path)))
- bb_perror_msg_and_die("No %s",path);
+ dir = opendir(path);
+ if (dir == NULL)
+ return;
- for(;;) {
- struct dirent *entry = readdir(dir);
-
- if(!entry) break;
+ while ((entry = readdir(dir)) != NULL) {
+ struct stat st;
/* Skip "." and ".." (also skips hidden files, which is ok) */
- if (entry->d_name[0]=='.') continue;
+ if (entry->d_name[0] == '.')
+ continue;
+
+ // uClibc doesn't fill out entry->d_type reliably. so we use lstat().
+
+ snprintf(path+len, PATH_MAX-len, "/%s", entry->d_name);
+ if (!lstat(path, &st) && S_ISDIR(st.st_mode)) find_dev(path);
+ path[len] = 0;
- if (entry->d_type == DT_DIR) {
- snprintf(path+len, PATH_MAX-len, "/%s", entry->d_name);
- find_dev(path);
- path[len] = 0;
- }
-
/* If there's a dev entry, mknod it */
-
- if (strcmp(entry->d_name, "dev")) make_device(path);
+
+ if (!strcmp(entry->d_name, "dev")) make_device(path, 0);
}
-
+
closedir(dir);
}
-int mdev_main(int argc, char *argv[])
+int mdev_main(int argc, char **argv);
+int mdev_main(int argc, char **argv)
{
- if (argc > 1) {
- if(argc == 2 && !strcmp(argv[1],"-s")) {
- RESERVE_CONFIG_BUFFER(temp,PATH_MAX);
- strcpy(temp,"/sys/block");
- find_dev(temp);
- strcpy(temp,"/sys/class");
- find_dev(temp);
- if(ENABLE_FEATURE_CLEAN_UP)
- RELEASE_CONFIG_BUFFER(temp);
- return 0;
- } else bb_show_usage();
- }
-
-/* hotplug support goes here */
-
+ char *action;
+ char *env_path;
+ RESERVE_CONFIG_BUFFER(temp,PATH_MAX);
+
+ xchdir(DEV_PATH);
+
+ /* Scan */
+
+ if (argc == 2 && !strcmp(argv[1],"-s")) {
+ struct stat st;
+
+ xstat("/", &st);
+ bbg.root_major = major(st.st_dev);
+ bbg.root_minor = minor(st.st_dev);
+ strcpy(temp,"/sys/block");
+ find_dev(temp);
+ strcpy(temp,"/sys/class");
+ find_dev(temp);
+
+ /* Hotplug */
+
+ } else {
+ action = getenv("ACTION");
+ env_path = getenv("DEVPATH");
+ if (!action || !env_path)
+ bb_show_usage();
+
+ sprintf(temp, "/sys%s", env_path);
+ if (!strcmp(action, "add")) make_device(temp,0);
+ else if (!strcmp(action, "remove")) make_device(temp,1);
+ }
+
+ if (ENABLE_FEATURE_CLEAN_UP) RELEASE_CONFIG_BUFFER(temp);
return 0;
}
projects / oweals / busybox.git / blobdiff