kumquat-buildroot/package/makedevs/makedevs.c
Lang Daniel d6d8d60ee3 package/makedevs: fix recursive chmod
The logic implemented in e745c0b to stop makedevs from recursively running
chmod() on dangling symlinks excluded everything that isn't a symlink.
Other file types or directories are skipped/ignored.

Logic has been updated to exit the function if mode shouldn't be changed
or if path is a dangling symlink.

Signed-off-by: Daniel Lang <d.lang@abatec.at>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
2022-09-17 23:36:10 +02:00

651 lines
16 KiB
C

/* vi: set sw=4 ts=4: */
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* 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 Library 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.
*
*/
#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <getopt.h>
#include <time.h>
#include <pwd.h>
#include <grp.h>
#include <unistd.h>
#include <ctype.h>
#include <errno.h>
#include <libgen.h>
#include <stdarg.h>
#include <sys/stat.h>
#include <sys/types.h>
#ifndef __APPLE__
#include <sys/sysmacros.h> /* major() and minor() */
#endif
#include <ftw.h>
#ifdef EXTENDED_ATTRIBUTES
#include <sys/capability.h>
#endif /* EXTENDED_ATTRIBUTES */
const char *bb_applet_name;
uid_t recursive_uid;
gid_t recursive_gid;
unsigned int recursive_mode;
#define PASSWD_PATH "etc/passwd" /* MUST be relative */
#define GROUP_PATH "etc/group" /* MUST be relative */
void bb_verror_msg(const char *s, va_list p)
{
fflush(stdout);
fprintf(stderr, "%s: ", bb_applet_name);
vfprintf(stderr, s, p);
}
void bb_error_msg(const char *s, ...)
{
va_list p;
va_start(p, s);
bb_verror_msg(s, p);
va_end(p);
putc('\n', stderr);
}
void bb_error_msg_and_die(const char *s, ...)
{
va_list p;
va_start(p, s);
bb_verror_msg(s, p);
va_end(p);
putc('\n', stderr);
exit(1);
}
void bb_vperror_msg(const char *s, va_list p)
{
int err=errno;
if(s == 0) s = "";
bb_verror_msg(s, p);
if (*s) s = ": ";
fprintf(stderr, "%s%s\n", s, strerror(err));
}
void bb_perror_msg(const char *s, ...)
{
va_list p;
va_start(p, s);
bb_vperror_msg(s, p);
va_end(p);
}
void bb_perror_msg_and_die(const char *s, ...)
{
va_list p;
va_start(p, s);
bb_vperror_msg(s, p);
va_end(p);
exit(1);
}
FILE *bb_xfopen(const char *path, const char *mode)
{
FILE *fp;
if ((fp = fopen(path, mode)) == NULL)
bb_perror_msg_and_die("%s", path);
return fp;
}
enum {
FILEUTILS_PRESERVE_STATUS = 1,
FILEUTILS_DEREFERENCE = 2,
FILEUTILS_RECUR = 4,
FILEUTILS_FORCE = 8,
FILEUTILS_INTERACTIVE = 16
};
int bb_make_directory (char *path, long mode, int flags)
{
mode_t mask;
const char *fail_msg;
char *s = path;
char c;
struct stat st;
mask = umask(0);
if (mode == -1) {
umask(mask);
mode = (S_IXUSR | S_IXGRP | S_IXOTH |
S_IWUSR | S_IWGRP | S_IWOTH |
S_IRUSR | S_IRGRP | S_IROTH) & ~mask;
} else {
umask(mask & ~0300);
}
do {
c = 0;
if (flags & FILEUTILS_RECUR) { /* Get the parent. */
/* Bypass leading non-'/'s and then subsequent '/'s. */
while (*s) {
if (*s == '/') {
do {
++s;
} while (*s == '/');
c = *s; /* Save the current char */
*s = 0; /* and replace it with nul. */
break;
}
++s;
}
}
if (mkdir(path, 0777) < 0) {
/* If we failed for any other reason than the directory
* already exists, output a diagnostic and return -1.*/
if ((errno != EEXIST && errno != EISDIR)
|| !(flags & FILEUTILS_RECUR)
|| (stat(path, &st) < 0 || !S_ISDIR(st.st_mode))) {
fail_msg = "create";
umask(mask);
break;
}
/* Since the directory exists, don't attempt to change
* permissions if it was the full target. Note that
* this is not an error conditon. */
if (!c) {
umask(mask);
return 0;
}
}
if (!c) {
/* Done. If necessary, updated perms on the newly
* created directory. Failure to update here _is_
* an error.*/
umask(mask);
if ((mode != -1) && (chmod(path, mode) < 0)){
fail_msg = "set permissions of";
break;
}
return 0;
}
/* Remove any inserted nul from the path (recursive mode). */
*s = c;
} while (1);
bb_perror_msg ("Cannot %s directory `%s'", fail_msg, path);
return -1;
}
const char * const bb_msg_memory_exhausted = "memory exhausted";
void *xmalloc(size_t size)
{
void *ptr = malloc(size);
if (ptr == NULL && size != 0)
bb_error_msg_and_die(bb_msg_memory_exhausted);
return ptr;
}
void *xcalloc(size_t nmemb, size_t size)
{
void *ptr = calloc(nmemb, size);
if (ptr == NULL && nmemb != 0 && size != 0)
bb_error_msg_and_die(bb_msg_memory_exhausted);
return ptr;
}
void *xrealloc(void *ptr, size_t size)
{
ptr = realloc(ptr, size);
if (ptr == NULL && size != 0)
bb_error_msg_and_die(bb_msg_memory_exhausted);
return ptr;
}
char *private_get_line_from_file(FILE *file, int c)
{
#define GROWBY (80) /* how large we will grow strings by */
int ch;
int idx = 0;
char *linebuf = NULL;
int linebufsz = 0;
while ((ch = getc(file)) != EOF) {
/* grow the line buffer as necessary */
if (idx > linebufsz - 2) {
linebuf = xrealloc(linebuf, linebufsz += GROWBY);
}
linebuf[idx++] = (char)ch;
if (!ch) return linebuf;
if (c<2 && ch == '\n') {
if (c) {
--idx;
}
break;
}
}
if (linebuf) {
if (ferror(file)) {
free(linebuf);
return NULL;
}
linebuf[idx] = 0;
}
return linebuf;
}
char *bb_get_chomped_line_from_file(FILE *file)
{
return private_get_line_from_file(file, 1);
}
long my_getpwnam(const char *name)
{
struct passwd *myuser;
FILE *stream;
stream = bb_xfopen(PASSWD_PATH, "r");
while(1) {
errno = 0;
myuser = fgetpwent(stream);
if (myuser == NULL)
bb_error_msg_and_die("unknown user name: %s", name);
if (errno)
bb_perror_msg_and_die("fgetpwent");
if (!strcmp(name, myuser->pw_name))
break;
}
fclose(stream);
return myuser->pw_uid;
}
long my_getgrnam(const char *name)
{
struct group *mygroup;
FILE *stream;
stream = bb_xfopen(GROUP_PATH, "r");
while(1) {
errno = 0;
mygroup = fgetgrent(stream);
if (mygroup == NULL)
bb_error_msg_and_die("unknown group name: %s", name);
if (errno)
bb_perror_msg_and_die("fgetgrent");
if (!strcmp(name, mygroup->gr_name))
break;
}
fclose(stream);
return mygroup->gr_gid;
}
unsigned long get_ug_id(const char *s, long (*my_getxxnam)(const char *))
{
unsigned long r;
char *p;
r = strtoul(s, &p, 10);
if (*p || (s == p)) {
r = my_getxxnam(s);
}
return r;
}
char * last_char_is(const char *s, int c)
{
char *sret = (char *)s;
if (sret) {
sret = strrchr(sret, c);
if(sret != NULL && *(sret+1) != 0)
sret = NULL;
}
return sret;
}
void bb_xasprintf(char **string_ptr, const char *format, ...)
{
va_list p;
int r;
va_start(p, format);
r = vasprintf(string_ptr, format, p);
va_end(p);
if (r < 0) {
bb_perror_msg_and_die("bb_xasprintf");
}
}
char *concat_path_file(const char *path, const char *filename)
{
char *outbuf;
char *lc;
if (!path)
path = "";
lc = last_char_is(path, '/');
while (*filename == '/')
filename++;
bb_xasprintf(&outbuf, "%s%s%s", path, (lc==NULL ? "/" : ""), filename);
return outbuf;
}
#ifdef EXTENDED_ATTRIBUTES
int bb_set_xattr(const char *fpath, const char *xattr)
{
cap_t cap, cap_file, cap_new;
char *cap_file_text, *cap_new_text;
ssize_t length;
cap = cap_from_text(xattr);
if (cap == NULL)
bb_perror_msg_and_die("cap_from_text failed for %s", xattr);
cap_file = cap_get_file(fpath);
if (cap_file == NULL) {
/* if no capability was set before, we initialize cap_file */
if (errno != ENODATA)
bb_perror_msg_and_die("cap_get_file failed on %s", fpath);
cap_file = cap_init();
if (!cap_file)
bb_perror_msg_and_die("cap_init failed");
}
if ((cap_file_text = cap_to_text(cap_file, &length)) == NULL)
bb_perror_msg_and_die("cap_to_name failed on %s", fpath);
bb_xasprintf(&cap_new_text, "%s %s", cap_file_text, xattr);
if ((cap_new = cap_from_text(cap_new_text)) == NULL)
bb_perror_msg_and_die("cap_from_text failed on %s", cap_new_text);
if (cap_set_file(fpath, cap_new) == -1)
bb_perror_msg_and_die("cap_set_file failed for %s (xattr = %s)", fpath, xattr);
cap_free(cap);
cap_free(cap_file);
cap_free(cap_file_text);
cap_free(cap_new);
cap_free(cap_new_text);
return 0;
}
#endif /* EXTENDED_ATTRIBUTES */
void bb_show_usage(void)
{
fprintf(stderr, "%s: [-d device_table] rootdir\n\n", bb_applet_name);
fprintf(stderr, "Creates a batch of special files as specified in a device table.\n");
fprintf(stderr, "Device table entries take the form of:\n");
fprintf(stderr, "name type mode user group major minor start increment count\n\n");
fprintf(stderr, "Where name is the file name, type can be one of:\n");
fprintf(stderr, " f A regular file\n");
fprintf(stderr, " d Directory\n");
fprintf(stderr, " r Directory recursively\n");
fprintf(stderr, " c Character special device file\n");
fprintf(stderr, " b Block special device file\n");
fprintf(stderr, " p Fifo (named pipe)\n");
fprintf(stderr, "uid is the user id for the target file, gid is the group id for the\n");
fprintf(stderr, "target file. The rest of the entries (major, minor, etc) apply to\n");
fprintf(stderr, "to device special files. A '-' may be used for blank entries.\n\n");
fprintf(stderr, "For example:\n");
fprintf(stderr, "<name> <type> <mode> <uid> <gid> <major> <minor> <start> <inc> <count>\n");
fprintf(stderr, "/dev d 755 0 0 - - - - -\n");
fprintf(stderr, "/dev/console c 666 0 0 5 1 - - -\n");
fprintf(stderr, "/dev/null c 666 0 0 1 3 0 0 -\n");
fprintf(stderr, "/dev/zero c 666 0 0 1 5 0 0 -\n");
fprintf(stderr, "/dev/hda b 640 0 0 3 0 0 0 -\n");
fprintf(stderr, "/dev/hda b 640 0 0 3 1 1 1 15\n");
fprintf(stderr, "/dev/rtp b 640 0 0 250 0 0 1 5\n");
fprintf(stderr, "/dev/gps b 640 0 0 251 0 1 1 5\n");
fprintf(stderr, "/dev/uio b 640 0 0 252 0 1 2 5\n");
fprintf(stderr, "/dev/uio b 640 0 0 252 1 6 2 5\n\n");
fprintf(stderr, "Will Produce:\n");
fprintf(stderr, "/dev\n");
fprintf(stderr, "/dev/console\n");
fprintf(stderr, "/dev/null\n");
fprintf(stderr, "/dev/zero\n");
fprintf(stderr, "/dev/hda\n");
fprintf(stderr, "/dev/hda[1-15] with minor numbers [1-15]\n");
fprintf(stderr, "/dev/rtp[0-4] with minor numbers [0-4]\n");
fprintf(stderr, "/dev/gps[1-5] with minor numbers [0-4]\n");
fprintf(stderr, "/dev/uio[1-5] with minor numbers 0,2,4,6,8\n");
fprintf(stderr, "/dev/uio[6-10] with minor numbers 1,3,5,7,9\n");
exit(1);
}
int bb_recursive(const char *fpath, const struct stat *sb,
int tflag, struct FTW *ftwbuf){
if (lchown(fpath, recursive_uid, recursive_gid) == -1) {
bb_perror_msg("chown failed for %s", fpath);
return -1;
}
/* chmod() is optional, also skip if dangling symlink */
if (recursive_mode == -1 || (tflag == FTW_SL && !access(fpath, F_OK)))
return 0;
if (chmod(fpath, recursive_mode) < 0) {
bb_perror_msg("chmod failed for %s", fpath);
return -1;
}
return 0;
}
int main(int argc, char **argv)
{
int opt;
FILE *table = stdin;
char *rootdir = NULL;
char *full_name = NULL;
char *line = NULL;
int linenum = 0;
int ret = EXIT_SUCCESS;
bb_applet_name = basename(argv[0]);
while ((opt = getopt(argc, argv, "d:")) != -1) {
switch(opt) {
case 'd':
table = bb_xfopen((line=optarg), "r");
break;
default:
bb_show_usage();
}
}
if (optind >= argc || (rootdir=argv[optind])==NULL) {
bb_error_msg_and_die("root directory not speficied");
}
if (chdir(rootdir) != 0) {
bb_perror_msg_and_die("Couldnt chdir to %s", rootdir);
}
umask(0);
printf("rootdir=%s\n", rootdir);
if (line) {
printf("table='%s'\n", line);
} else {
printf("table=<stdin>\n");
}
while ((line = bb_get_chomped_line_from_file(table))) {
char type;
unsigned int mode = 0755;
unsigned int major = 0;
unsigned int minor = 0;
unsigned int count = 0;
unsigned int increment = 0;
unsigned int start = 0;
char xattr[255];
char name[4096];
char user[41];
char group[41];
uid_t uid;
gid_t gid;
linenum++;
if (1 == sscanf(line, " |xattr %254s", xattr)) {
#ifdef EXTENDED_ATTRIBUTES
if (!full_name)
bb_error_msg_and_die("line %d should be after a file\n", linenum);
if (bb_set_xattr(full_name, xattr) < 0)
bb_error_msg_and_die("can't set cap %s on file %s\n", xattr, full_name);
#else
bb_error_msg_and_die("line %d not supported: '%s'\nDid you forget to enable "
"BR2_ROOTFS_DEVICE_TABLE_SUPPORTS_EXTENDED_ATTRIBUTES?\n",
linenum, line);
#endif /* EXTENDED_ATTRIBUTES */
continue;
}
if ((2 > sscanf(line, "%4095s %c %o %40s %40s %u %u %u %u %u", name,
&type, &mode, user, group, &major,
&minor, &start, &increment, &count)) ||
((major | minor | start | count | increment) > 0xfffff))
{
if (*line=='\0' || *line=='#' || isspace(*line))
continue;
bb_error_msg("line %d invalid: '%s'\n", linenum, line);
ret = EXIT_FAILURE;
continue;
}
if (name[0] == '#') {
continue;
}
if (*group) {
gid = get_ug_id(group, my_getgrnam);
} else {
gid = getgid();
}
if (*user) {
uid = get_ug_id(user, my_getpwnam);
} else {
uid = getuid();
}
/*
* free previous full name
* we don't de-allocate full_name at the end of the parsing,
* because we may need it if the next line is an xattr.
*/
free(full_name);
full_name = concat_path_file(rootdir, name);
if (type == 'd') {
bb_make_directory(full_name, mode | S_IFDIR, FILEUTILS_RECUR);
if (chown(full_name, uid, gid) == -1) {
bb_perror_msg("line %d: chown failed for %s", linenum, full_name);
ret = EXIT_FAILURE;
goto loop;
}
if ((mode != -1) && (chmod(full_name, mode) < 0)){
bb_perror_msg("line %d: chmod failed for %s", linenum, full_name);
ret = EXIT_FAILURE;
goto loop;
}
} else if (type == 'f' || type == 'F') {
struct stat st;
if ((stat(full_name, &st) < 0 || !S_ISREG(st.st_mode))) {
if (type == 'F') {
continue; /*Ignore optional files*/
}
bb_perror_msg("line %d: regular file '%s' does not exist", linenum, full_name);
ret = EXIT_FAILURE;
goto loop;
}
if (chown(full_name, uid, gid) == -1) {
bb_perror_msg("line %d: chown failed for %s", linenum, full_name);
ret = EXIT_FAILURE;
goto loop;
}
if ((mode != -1) && (chmod(full_name, mode) < 0)){
bb_perror_msg("line %d: chmod failed for %s", linenum, full_name);
ret = EXIT_FAILURE;
goto loop;
}
} else if (type == 'r') {
recursive_uid = uid;
recursive_gid = gid;
recursive_mode = mode;
if (nftw(full_name, bb_recursive, 20, FTW_MOUNT | FTW_PHYS) < 0) {
bb_perror_msg("line %d: recursive failed for %s", linenum, full_name);
ret = EXIT_FAILURE;
goto loop;
}
} else
{
dev_t rdev;
unsigned i;
char *full_name_inc;
if (type == 'p') {
mode |= S_IFIFO;
}
else if (type == 'c') {
mode |= S_IFCHR;
}
else if (type == 'b') {
mode |= S_IFBLK;
} else {
bb_error_msg("line %d: Unsupported file type %c", linenum, type);
ret = EXIT_FAILURE;
goto loop;
}
full_name_inc = xmalloc(strlen(full_name) + sizeof(int)*3 + 2);
if (count)
count--;
for (i = start; i <= start + count; i++) {
sprintf(full_name_inc, count ? "%s%u" : "%s", full_name, i);
rdev = makedev(major, minor + (i - start) * increment);
if (mknod(full_name_inc, mode, rdev) < 0) {
bb_perror_msg("line %d: can't create node %s", linenum, full_name_inc);
ret = EXIT_FAILURE;
} else if (lchown(full_name_inc, uid, gid) < 0) {
bb_perror_msg("line %d: can't chown %s", linenum, full_name_inc);
ret = EXIT_FAILURE;
} else if (chmod(full_name_inc, mode) < 0) {
bb_perror_msg("line %d: can't chmod %s", linenum, full_name_inc);
ret = EXIT_FAILURE;
}
}
free(full_name_inc);
}
loop:
free(line);
}
fclose(table);
return ret;
}