* Licensed under GPL version 2, see file LICENSE in this tarball for details.
*/
-#include "busybox.h"
+#include "libbb.h"
#include "xregex.h"
-#define DEV_PATH "/dev"
+struct globals {
+ int root_major, root_minor;
+};
+#define G (*(struct globals*)&bb_common_bufsiz1)
+#define root_major (G.root_major)
+#define root_minor (G.root_minor)
+
+/* Prevent infinite loops in /sys symlinks */
+#define MAX_SYSFS_DEPTH 3
-struct mdev_globals
+/* We use additional 64+ bytes in make_device() */
+#define SCRATCH_SIZE 80
+
+#if ENABLE_FEATURE_MDEV_RENAME
+/* Builds an alias path.
+ * This function potentionally reallocates the alias parameter.
+ */
+static char *build_alias(char *alias, const char *device_name)
{
- int root_major, root_minor;
-} mdev_globals;
+ char *dest;
+
+ /* ">bar/": rename to bar/device_name */
+ /* ">bar[/]baz": rename to bar[/]baz */
+ dest = strrchr(alias, '/');
+ if (dest) { /* ">bar/[baz]" ? */
+ *dest = '\0'; /* mkdir bar */
+ bb_make_directory(alias, 0755, FILEUTILS_RECUR);
+ *dest = '/';
+ if (dest[1] == '\0') { /* ">bar/" => ">bar/device_name" */
+ dest = alias;
+ alias = concat_path_file(alias, device_name);
+ free(dest);
+ }
+ }
-#define bbg mdev_globals
+ return alias;
+}
+#endif
/* mknod in /dev based on a path like "/sys/block/hda/hda1" */
+/* NB: "mdev -s" may call us many times, do not leak memory/fds! */
static void make_device(char *path, int delete)
{
- char *device_name;
- int major, minor, type, len, fd;
+ const char *device_name;
+ int major, minor, type, len;
int mode = 0660;
- uid_t uid = 0;
- gid_t gid = 0;
- char *temp = path + strlen(path);
+#if ENABLE_FEATURE_MDEV_CONF
+ struct bb_uidgid_t ugid = { 0, 0 };
+ parser_t *parser;
+ char *tokens[5];
+#endif
+#if ENABLE_FEATURE_MDEV_EXEC
char *command = NULL;
+#endif
+#if ENABLE_FEATURE_MDEV_RENAME
+ char *alias = NULL;
+ char aliaslink = aliaslink; /* for compiler */
+#endif
+ char *dev_maj_min = path + strlen(path);
+
+ /* Force the configuration file settings exactly. */
+ umask(0);
/* 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. */
-
+ * because sscanf() will stop at the first nondigit, which \n is.
+ * We also depend on path having writeable space after it.
+ */
+ major = -1;
if (!delete) {
- strcat(path, "/dev");
- len = open_read_close(path, temp + 1, 64);
- *temp++ = 0;
- if (len < 1) return;
+ strcpy(dev_maj_min, "/dev");
+ len = open_read_close(path, dev_maj_min + 1, 64);
+ *dev_maj_min++ = '\0';
+ if (len < 1) {
+ if (!ENABLE_FEATURE_MDEV_EXEC)
+ return;
+ /* no "dev" file, so just try to run script */
+ *dev_maj_min = '\0';
+ } else if (sscanf(dev_maj_min, "%u:%u", &major, &minor) != 2) {
+ major = -1;
+ }
}
/* Determine device name, type, major and minor */
+ device_name = bb_basename(path);
+ /* http://kernel.org/doc/pending/hotplug.txt says that only
+ * "/sys/block/..." is for block devices. "/sys/bus" etc is not.
+ * But since 2.6.25 block devices are also in /sys/class/block.
+ * We use strstr("/block/") to forestall future surprises. */
+ type = S_IFCHR;
+ if (strstr(path, "/block/"))
+ type = S_IFBLK;
+
+#if ENABLE_FEATURE_MDEV_CONF
+ parser = config_open2("/etc/mdev.conf", fopen_for_read);
+
+ /* If we have config file, look up user settings */
+ while (config_read(parser, tokens, 4, 3, "# \t", PARSE_NORMAL)) {
+ regmatch_t off[1 + 9*ENABLE_FEATURE_MDEV_RENAME_REGEXP];
+ char *val;
+
+ /* Fields: regex uid:gid mode [alias] [cmd] */
+
+ /* 1st field: @<numeric maj,min>... */
+ if (tokens[0][0] == '@') {
+ /* @major,minor[-last] */
+ /* (useful when name is ambiguous:
+ * "/sys/class/usb/lp0" and
+ * "/sys/class/printer/lp0") */
+ int cmaj, cmin0, cmin1, sc;
+ if (major < 0)
+ continue; /* no dev, no match */
+ sc = sscanf(tokens[0], "@%u,%u-%u", &cmaj, &cmin0, &cmin1);
+ if (sc < 1 || major != cmaj
+ || (sc == 2 && minor != cmin0)
+ || (sc == 3 && (minor < cmin0 || minor > cmin1))
+ ) {
+ continue; /* no match */
+ }
+ } else { /* ... or regex to match device name */
+ regex_t match;
+ int result;
+
+ /* Is this it? */
+ xregcomp(&match, tokens[0], REG_EXTENDED);
+ result = regexec(&match, device_name, ARRAY_SIZE(off), off, 0);
+ regfree(&match);
+
+ //bb_error_msg("matches:");
+ //for (int i = 0; i < ARRAY_SIZE(off); i++) {
+ // if (off[i].rm_so < 0) continue;
+ // bb_error_msg("match %d: '%.*s'\n", i,
+ // (int)(off[i].rm_eo - off[i].rm_so),
+ // device_name + off[i].rm_so);
+ //}
+
+ /* If not this device, skip rest of line */
+ /* (regexec returns whole pattern as "range" 0) */
+ if (result || off[0].rm_so
+ || ((int)off[0].rm_eo != (int)strlen(device_name))
+ ) {
+ continue;
+ }
+ }
- device_name = strrchr(path, '/') + 1;
- 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;
-
- /* mmap the config file */
- if (-1 != (fd=open("/etc/mdev.conf",O_RDONLY))) {
- len = lseek(fd, 0, SEEK_END);
- conf = mmap(NULL, len, PROT_READ, MAP_PRIVATE, fd, 0);
- if (conf) {
- int 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) {
- /* 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;
-
- } else 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;
- }
- } else if (field == 2) {
- /* mode */
-
- mode = strtoul(pos, &pos, 8);
- if (pos != end2) break;
- } else if (ENABLE_FEATURE_MDEV_EXEC && field == 3) {
- // Command to run
- char *s = "@$*", *s2;
- if (!(s2 = strchr(s, *pos++))) {
- // Force error
- field = 1;
- break;
- }
- if ((s2-s+1) & (1<<delete))
- command = xstrndup(pos, end-pos);
- }
-
- pos = end2;
+ /* This line matches: stop parsing the file
+ * after parsing the rest of fields */
+
+ /* 2nd field: uid:gid - device ownership */
+ parse_chown_usergroup_or_die(&ugid, tokens[1]);
+
+ /* 3rd field: mode - device permissions */
+ mode = strtoul(tokens[2], NULL, 8);
+
+ val = tokens[3];
+ /* 4th field (opt): >alias */
+#if ENABLE_FEATURE_MDEV_RENAME
+ if (!val)
+ break;
+ aliaslink = *val;
+ if (aliaslink == '>' || aliaslink == '=') {
+ char *s;
+#if ENABLE_FEATURE_MDEV_RENAME_REGEXP
+ char *p;
+ unsigned i, n;
+#endif
+ char *a = val;
+ s = strchrnul(val, ' ');
+ val = (s[0] && s[1]) ? s+1 : NULL;
+ s[0] = '\0';
+#if ENABLE_FEATURE_MDEV_RENAME_REGEXP
+ /* substitute %1..9 with off[1..9], if any */
+ n = 0;
+ s = a;
+ while (*s)
+ if (*s++ == '%')
+ n++;
+
+ p = alias = xzalloc(strlen(a) + n * strlen(device_name));
+ s = a + 1;
+ while (*s) {
+ *p = *s;
+ if ('%' == *s) {
+ i = (s[1] - '0');
+ if (i <= 9 && off[i].rm_so >= 0) {
+ n = off[i].rm_eo - off[i].rm_so;
+ strncpy(p, device_name + off[i].rm_so, n);
+ p += n - 1;
+ s++;
}
-
- /* Did everything parse happily? */
-
- if (field > 2) break;
- if (field) bb_error_msg_and_die("Bad line %d",line);
-
- /* Next line */
- pos = ++end;
}
- munmap(conf, len);
+ p++;
+ s++;
}
- close(fd);
+#else
+ alias = xstrdup(a + 1);
+#endif
}
- }
+#endif /* ENABLE_FEATURE_MDEV_RENAME */
+
+#if ENABLE_FEATURE_MDEV_EXEC
+ /* The rest (opt): command to run */
+ if (!val)
+ break;
+ {
+ const char *s = "@$*";
+ const char *s2 = strchr(s, *val);
+
+ if (!s2)
+ bb_error_msg_and_die("bad line %u", parser->lineno);
+
+ /* Correlate the position in the "@$*" with the delete
+ * step so that we get the proper behavior:
+ * @cmd: run on create
+ * $cmd: run on delete
+ * *cmd: run on both
+ */
+ if ((s2 - s + 1) /*1/2/3*/ & /*1/2*/ (1 + delete)) {
+ command = xstrdup(val + 1);
+ }
+ }
+#endif
+ /* end of field parsing */
+ break; /* we found matching line, stop */
+ } /* end of "while line is read from /etc/mdev.conf" */
+
+ config_close(parser);
+#endif /* ENABLE_FEATURE_MDEV_CONF */
+
+ if (!delete && major >= 0) {
+
+ if (ENABLE_FEATURE_MDEV_RENAME)
+ unlink(device_name);
- 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 failed", device_name);
+ bb_perror_msg_and_die("mknod %s", device_name);
- if (major == bbg.root_major && minor == bbg.root_minor)
+ if (major == root_major && minor == root_minor)
symlink(device_name, "root");
- if (ENABLE_FEATURE_MDEV_CONF) chown(device_name, uid, gid);
+#if ENABLE_FEATURE_MDEV_CONF
+ chown(device_name, ugid.uid, ugid.gid);
+
+#if ENABLE_FEATURE_MDEV_RENAME
+ if (alias) {
+ alias = build_alias(alias, device_name);
+
+ /* move the device, and optionally
+ * make a symlink to moved device node */
+ if (rename(device_name, alias) == 0 && aliaslink == '>')
+ symlink(alias, device_name);
+
+ free(alias);
+ }
+#endif
+#endif
}
- if (command) {
- int rc;
- char *s;
- s=xasprintf("MDEV=%s",device_name);
- putenv(s);
- rc = system(command);
- s[4]=0;
+#if ENABLE_FEATURE_MDEV_EXEC
+ if (command) {
+ /* setenv will leak memory, use putenv/unsetenv/free */
+ char *s = xasprintf("MDEV=%s", device_name);
putenv(s);
+ if (system(command) == -1)
+ bb_perror_msg_and_die("can't run '%s'", command);
+ unsetenv("MDEV");
free(s);
free(command);
- if (rc == -1) bb_perror_msg_and_die("cannot run %s", command);
}
- if (delete) unlink(device_name);
+#endif
+
+ if (delete) {
+ unlink(device_name);
+ /* At creation time, device might have been moved
+ * and a symlink might have been created. Undo that. */
+#if ENABLE_FEATURE_MDEV_RENAME
+ if (alias) {
+ alias = build_alias(alias, device_name);
+ unlink(alias);
+ free(alias);
+ }
+#endif
+ }
}
-/* 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. */
-
-static void find_dev(char *path)
+/* File callback for /sys/ traversal */
+static int FAST_FUNC fileAction(const char *fileName,
+ struct stat *statbuf UNUSED_PARAM,
+ void *userData,
+ int depth UNUSED_PARAM)
{
- DIR *dir;
- size_t len = strlen(path);
- struct dirent *entry;
-
- if ((dir = opendir(path)) == NULL)
- return;
-
- while ((entry = readdir(dir)) != NULL) {
- struct stat st;
-
- /* Skip "." and ".." (also skips hidden files, which is ok) */
+ size_t len = strlen(fileName) - 4; /* can't underflow */
+ char *scratch = userData;
- if (entry->d_name[0] == '.')
- continue;
+ /* len check is for paranoid reasons */
+ if (strcmp(fileName + len, "/dev") != 0 || len >= PATH_MAX)
+ return FALSE;
- // uClibc doesn't fill out entry->d_type reliably. so we use lstat().
+ strcpy(scratch, fileName);
+ scratch[len] = '\0';
+ make_device(scratch, 0);
- 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;
+ return TRUE;
+}
- /* If there's a dev entry, mknod it */
+/* Directory callback for /sys/ traversal */
+static int FAST_FUNC dirAction(const char *fileName UNUSED_PARAM,
+ struct stat *statbuf UNUSED_PARAM,
+ void *userData UNUSED_PARAM,
+ int depth)
+{
+ return (depth >= MAX_SYSFS_DEPTH ? SKIP : TRUE);
+}
- if (!strcmp(entry->d_name, "dev")) make_device(path, 0);
+/* For the full gory details, see linux/Documentation/firmware_class/README
+ *
+ * Firmware loading works like this:
+ * - kernel sets FIRMWARE env var
+ * - userspace checks /lib/firmware/$FIRMWARE
+ * - userspace waits for /sys/$DEVPATH/loading to appear
+ * - userspace writes "1" to /sys/$DEVPATH/loading
+ * - userspace copies /lib/firmware/$FIRMWARE into /sys/$DEVPATH/data
+ * - userspace writes "0" (worked) or "-1" (failed) to /sys/$DEVPATH/loading
+ * - kernel loads firmware into device
+ */
+static void load_firmware(const char *const firmware, const char *const sysfs_path)
+{
+ int cnt;
+ int firmware_fd, loading_fd, data_fd;
+
+ /* check for /lib/firmware/$FIRMWARE */
+ xchdir("/lib/firmware");
+ firmware_fd = xopen(firmware, O_RDONLY);
+
+ /* in case we goto out ... */
+ data_fd = -1;
+
+ /* check for /sys/$DEVPATH/loading ... give 30 seconds to appear */
+ xchdir(sysfs_path);
+ for (cnt = 0; cnt < 30; ++cnt) {
+ loading_fd = open("loading", O_WRONLY);
+ if (loading_fd != -1)
+ goto loading;
+ sleep(1);
+ }
+ goto out;
+
+ loading:
+ /* tell kernel we're loading by `echo 1 > /sys/$DEVPATH/loading` */
+ if (full_write(loading_fd, "1", 1) != 1)
+ goto out;
+
+ /* load firmware by `cat /lib/firmware/$FIRMWARE > /sys/$DEVPATH/data */
+ data_fd = open("data", O_WRONLY);
+ if (data_fd == -1)
+ goto out;
+ cnt = bb_copyfd_eof(firmware_fd, data_fd);
+
+ /* tell kernel result by `echo [0|-1] > /sys/$DEVPATH/loading` */
+ if (cnt > 0)
+ full_write(loading_fd, "0", 1);
+ else
+ full_write(loading_fd, "-1", 2);
+
+ out:
+ if (ENABLE_FEATURE_CLEAN_UP) {
+ close(firmware_fd);
+ close(loading_fd);
+ close(data_fd);
}
-
- closedir(dir);
}
-int mdev_main(int argc, char *argv[])
+int mdev_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int mdev_main(int argc UNUSED_PARAM, char **argv)
{
- char *action;
- char *env_path;
- RESERVE_CONFIG_BUFFER(temp,PATH_MAX);
-
- xchdir(DEV_PATH);
-
- /* Scan */
-
- if (argc == 2 && !strcmp(argv[1],"-s")) {
+ RESERVE_CONFIG_BUFFER(temp, PATH_MAX + SCRATCH_SIZE);
+
+ /* We can be called as hotplug helper */
+ /* Kernel cannot provide suitable stdio fds for us, do it ourself */
+#if 1
+ bb_sanitize_stdio();
+#else
+ /* Debug code */
+ /* Replace LOGFILE by other file or device name if you need */
+#define LOGFILE "/dev/console"
+ /* Just making sure fd 0 is not closed,
+ * we don't really intend to read from it */
+ xmove_fd(xopen("/", O_RDONLY), STDIN_FILENO);
+ xmove_fd(xopen(LOGFILE, O_WRONLY|O_APPEND), STDOUT_FILENO);
+ xmove_fd(xopen(LOGFILE, O_WRONLY|O_APPEND), STDERR_FILENO);
+#endif
+
+ xchdir("/dev");
+
+ if (argv[1] && !strcmp(argv[1], "-s")) {
+ /* Scan:
+ * mdev -s
+ */
struct stat st;
- stat("/", &st); // If this fails, we have bigger problems.
- 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 */
-
+ xstat("/", &st);
+ root_major = major(st.st_dev);
+ root_minor = minor(st.st_dev);
+
+ /* ACTION_FOLLOWLINKS is needed since in newer kernels
+ * /sys/block/loop* (for example) are symlinks to dirs,
+ * not real directories.
+ * (kernel's CONFIG_SYSFS_DEPRECATED makes them real dirs,
+ * but we can't enforce that on users)
+ */
+ if (access("/sys/class/block", F_OK) != 0) {
+ /* Scan obsolete /sys/block only if /sys/class/block
+ * doesn't exist. Otherwise we'll have dupes.
+ */
+ recursive_action("/sys/block",
+ ACTION_RECURSE | ACTION_FOLLOWLINKS,
+ // not needed now? | ACTION_QUIET
+ fileAction, dirAction, temp, 0);
+ }
+ recursive_action("/sys/class",
+ ACTION_RECURSE | ACTION_FOLLOWLINKS,
+ fileAction, dirAction, temp, 0);
} else {
+ char *seq;
+ char *action;
+ char *env_path;
+ char seqbuf[sizeof(int)*3 + 2];
+ int seqlen = seqlen; /* for compiler */
+
+ /* Hotplug:
+ * env ACTION=... DEVPATH=... [SEQNUM=...] mdev
+ * ACTION can be "add" or "remove"
+ * DEVPATH is like "/block/sda" or "/class/input/mice"
+ */
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);
+ seq = getenv("SEQNUM");
+ if (seq) {
+ int timeout = 2000 / 32;
+ do {
+ seqlen = open_read_close("mdev.seq", seqbuf, sizeof(seqbuf-1));
+ if (seqlen < 0)
+ break;
+ seqbuf[seqlen] = '\0';
+ if (seqbuf[0] == '\n' /* seed file? */
+ || strcmp(seq, seqbuf) == 0 /* correct idx? */
+ ) {
+ break;
+ }
+ usleep(32*1000);
+ } while (--timeout);
+ }
+
+ snprintf(temp, PATH_MAX, "/sys%s", env_path);
+ if (!strcmp(action, "remove"))
+ make_device(temp, 1);
+ else if (!strcmp(action, "add")) {
+ make_device(temp, 0);
+
+ if (ENABLE_FEATURE_MDEV_LOAD_FIRMWARE) {
+ char *fw = getenv("FIRMWARE");
+ if (fw)
+ load_firmware(fw, temp);
+ }
+ }
+
+ if (seq && seqlen >= 0) {
+ xopen_xwrite_close("mdev.seq", utoa(xatou(seq) + 1));
+ }
}
- if (ENABLE_FEATURE_CLEAN_UP) RELEASE_CONFIG_BUFFER(temp);
+ if (ENABLE_FEATURE_CLEAN_UP)
+ RELEASE_CONFIG_BUFFER(temp);
+
return 0;
}
projects / oweals / busybox.git / blobdiff