344 lines
9.0 KiB
C
344 lines
9.0 KiB
C
/* vi: set sw=4 ts=4: */
|
|
/*
|
|
* Mini copy_file implementation for busybox
|
|
*
|
|
* Copyright (C) 2001 by Matt Kraai <kraai@alumni.carnegiemellon.edu>
|
|
* SELinux support by Yuichi Nakamura <ynakam@hitachisoft.jp>
|
|
*
|
|
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
|
|
*
|
|
*/
|
|
|
|
#include "libbb.h"
|
|
|
|
// POSIX: if exists and -i, ask (w/o -i assume yes).
|
|
// Then open w/o EXCL (yes, not unlink!).
|
|
// If open still fails and -f, try unlink, then try open again.
|
|
// Result: a mess:
|
|
// If dest is a softlink, we overwrite softlink's destination!
|
|
// (or fail, if it points to dir/nonexistent location/etc).
|
|
// This is strange, but POSIX-correct.
|
|
// coreutils cp has --remove-destination to override this...
|
|
|
|
#define DO_POSIX_CP 0 /* 1 - POSIX behavior, 0 - safe behavior */
|
|
|
|
|
|
static int ask_and_unlink(const char *dest, int flags)
|
|
{
|
|
// If !DO_POSIX_CP, act as if -f is always in effect - we don't want
|
|
// "'file' exists" msg, we want unlink to be done (silently unless -i
|
|
// is also in effect).
|
|
// This prevents safe way from asking more questions than POSIX does.
|
|
#if DO_POSIX_CP
|
|
if (!(flags & (FILEUTILS_FORCE|FILEUTILS_INTERACTIVE))) {
|
|
fprintf(stderr, "'%s' exists\n", dest);
|
|
return -1;
|
|
}
|
|
#endif
|
|
|
|
// TODO: maybe we should do it only if ctty is present?
|
|
if (flags & FILEUTILS_INTERACTIVE) {
|
|
// We would not do POSIX insanity. -i asks,
|
|
// then _unlinks_ the offender. Presto.
|
|
// (No opening without O_EXCL, no unlinks only if -f)
|
|
// Or else we will end up having 3 open()s!
|
|
fprintf(stderr, "%s: overwrite '%s'? ", applet_name, dest);
|
|
if (!bb_ask_confirmation())
|
|
return 0; // not allowed to overwrite
|
|
}
|
|
if (unlink(dest) < 0) {
|
|
bb_perror_msg("cannot remove '%s'", dest);
|
|
return -1; // error
|
|
}
|
|
return 1; // ok (to try again)
|
|
}
|
|
|
|
/* Return:
|
|
* -1 error, copy not made
|
|
* 0 copy is made or user answered "no" in interactive mode
|
|
* (failures to preserve mode/owner/times are not reported in exit code)
|
|
*/
|
|
int copy_file(const char *source, const char *dest, int flags)
|
|
{
|
|
struct stat source_stat;
|
|
struct stat dest_stat;
|
|
int status = 0;
|
|
signed char dest_exists = 0;
|
|
signed char ovr;
|
|
|
|
#define FLAGS_DEREF (flags & FILEUTILS_DEREFERENCE)
|
|
|
|
if ((FLAGS_DEREF ? stat : lstat)(source, &source_stat) < 0) {
|
|
// This may be a dangling symlink.
|
|
// Making [sym]links to dangling symlinks works, so...
|
|
if (flags & (FILEUTILS_MAKE_SOFTLINK|FILEUTILS_MAKE_HARDLINK))
|
|
goto make_links;
|
|
bb_perror_msg("cannot stat '%s'", source);
|
|
return -1;
|
|
}
|
|
|
|
if (lstat(dest, &dest_stat) < 0) {
|
|
if (errno != ENOENT) {
|
|
bb_perror_msg("cannot stat '%s'", dest);
|
|
return -1;
|
|
}
|
|
} else {
|
|
if (source_stat.st_dev == dest_stat.st_dev
|
|
&& source_stat.st_ino == dest_stat.st_ino
|
|
) {
|
|
bb_error_msg("'%s' and '%s' are the same file", source, dest);
|
|
return -1;
|
|
}
|
|
dest_exists = 1;
|
|
}
|
|
|
|
#if ENABLE_SELINUX
|
|
if ((flags & FILEUTILS_PRESERVE_SECURITY_CONTEXT) && is_selinux_enabled() > 0) {
|
|
security_context_t con;
|
|
if (lgetfilecon(source, &con) >= 0) {
|
|
if (setfscreatecon(con) < 0) {
|
|
bb_perror_msg("cannot set setfscreatecon %s", con);
|
|
freecon(con);
|
|
return -1;
|
|
}
|
|
} else if (errno == ENOTSUP || errno == ENODATA) {
|
|
setfscreatecon_or_die(NULL);
|
|
} else {
|
|
bb_perror_msg("cannot lgetfilecon %s", source);
|
|
return -1;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
if (S_ISDIR(source_stat.st_mode)) {
|
|
DIR *dp;
|
|
struct dirent *d;
|
|
mode_t saved_umask = 0;
|
|
|
|
if (!(flags & FILEUTILS_RECUR)) {
|
|
bb_error_msg("omitting directory '%s'", source);
|
|
return -1;
|
|
}
|
|
|
|
/* Create DEST. */
|
|
if (dest_exists) {
|
|
if (!S_ISDIR(dest_stat.st_mode)) {
|
|
bb_error_msg("target '%s' is not a directory", dest);
|
|
return -1;
|
|
}
|
|
} else {
|
|
mode_t mode;
|
|
saved_umask = umask(0);
|
|
|
|
mode = source_stat.st_mode;
|
|
if (!(flags & FILEUTILS_PRESERVE_STATUS))
|
|
mode = source_stat.st_mode & ~saved_umask;
|
|
mode |= S_IRWXU;
|
|
|
|
if (mkdir(dest, mode) < 0) {
|
|
umask(saved_umask);
|
|
bb_perror_msg("cannot create directory '%s'", dest);
|
|
return -1;
|
|
}
|
|
|
|
umask(saved_umask);
|
|
}
|
|
|
|
/* Recursively copy files in SOURCE. */
|
|
dp = opendir(source);
|
|
if (dp == NULL) {
|
|
status = -1;
|
|
goto preserve_status;
|
|
}
|
|
|
|
while ((d = readdir(dp)) != NULL) {
|
|
char *new_source, *new_dest;
|
|
|
|
new_source = concat_subpath_file(source, d->d_name);
|
|
if (new_source == NULL)
|
|
continue;
|
|
new_dest = concat_path_file(dest, d->d_name);
|
|
if (copy_file(new_source, new_dest, flags) < 0)
|
|
status = -1;
|
|
free(new_source);
|
|
free(new_dest);
|
|
}
|
|
closedir(dp);
|
|
|
|
if (!dest_exists
|
|
&& chmod(dest, source_stat.st_mode & ~saved_umask) < 0
|
|
) {
|
|
bb_perror_msg("cannot change permissions of '%s'", dest);
|
|
status = -1;
|
|
}
|
|
|
|
} else if (flags & (FILEUTILS_MAKE_SOFTLINK|FILEUTILS_MAKE_HARDLINK)) {
|
|
int (*lf)(const char *oldpath, const char *newpath);
|
|
make_links:
|
|
// Hmm... maybe
|
|
// if (DEREF && MAKE_SOFTLINK) source = realpath(source) ?
|
|
// (but realpath returns NULL on dangling symlinks...)
|
|
lf = (flags & FILEUTILS_MAKE_SOFTLINK) ? symlink : link;
|
|
if (lf(source, dest) < 0) {
|
|
ovr = ask_and_unlink(dest, flags);
|
|
if (ovr <= 0)
|
|
return ovr;
|
|
if (lf(source, dest) < 0) {
|
|
bb_perror_msg("cannot create link '%s'", dest);
|
|
return -1;
|
|
}
|
|
}
|
|
return 0;
|
|
|
|
} else if (S_ISREG(source_stat.st_mode)
|
|
/* Huh? DEREF uses stat, which never returns links! */
|
|
/* || (FLAGS_DEREF && S_ISLNK(source_stat.st_mode)) */
|
|
) {
|
|
int src_fd;
|
|
int dst_fd;
|
|
if (ENABLE_FEATURE_PRESERVE_HARDLINKS) {
|
|
char *link_name;
|
|
|
|
if (!FLAGS_DEREF) {
|
|
link_name = is_in_ino_dev_hashtable(&source_stat);
|
|
if (link_name) {
|
|
if (link(link_name, dest) < 0) {
|
|
ovr = ask_and_unlink(dest, flags);
|
|
if (ovr <= 0)
|
|
return ovr;
|
|
if (link(link_name, dest) < 0) {
|
|
bb_perror_msg("cannot create link '%s'", dest);
|
|
return -1;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
}
|
|
add_to_ino_dev_hashtable(&source_stat, dest);
|
|
}
|
|
|
|
src_fd = open(source, O_RDONLY);
|
|
if (src_fd == -1) {
|
|
bb_perror_msg("cannot open '%s'", source);
|
|
return -1;
|
|
}
|
|
|
|
#if DO_POSIX_CP /* POSIX way (a security problem versus symlink attacks!): */
|
|
dst_fd = open(dest, (flags & FILEUTILS_INTERACTIVE)
|
|
? O_WRONLY|O_CREAT|O_EXCL
|
|
: O_WRONLY|O_CREAT|O_TRUNC, source_stat.st_mode);
|
|
#else /* safe way: */
|
|
dst_fd = open(dest, O_WRONLY|O_CREAT|O_EXCL, source_stat.st_mode);
|
|
#endif
|
|
if (dst_fd == -1) {
|
|
ovr = ask_and_unlink(dest, flags);
|
|
if (ovr <= 0) {
|
|
close(src_fd);
|
|
return ovr;
|
|
}
|
|
/* It shouldn't exist. If it exists, do not open (symlink attack?) */
|
|
dst_fd = open(dest, O_WRONLY|O_CREAT|O_EXCL, source_stat.st_mode);
|
|
if (dst_fd == -1) {
|
|
bb_perror_msg("cannot open '%s'", dest);
|
|
close(src_fd);
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
#if ENABLE_SELINUX
|
|
if (((flags & FILEUTILS_PRESERVE_SECURITY_CONTEXT)
|
|
|| (flags & FILEUTILS_SET_SECURITY_CONTEXT))
|
|
&& is_selinux_enabled() > 0
|
|
) {
|
|
security_context_t con;
|
|
if (getfscreatecon(&con) == -1) {
|
|
bb_perror_msg("getfscreatecon");
|
|
return -1;
|
|
}
|
|
if (con) {
|
|
if(setfilecon(dest, con) == -1) {
|
|
bb_perror_msg("setfilecon:%s,%s", dest, con);
|
|
freecon(con);
|
|
return -1;
|
|
}
|
|
freecon(con);
|
|
}
|
|
}
|
|
#endif
|
|
if (bb_copyfd_eof(src_fd, dst_fd) == -1)
|
|
status = -1;
|
|
if (close(dst_fd) < 0) {
|
|
bb_perror_msg("cannot close '%s'", dest);
|
|
status = -1;
|
|
}
|
|
if (close(src_fd) < 0) {
|
|
bb_perror_msg("cannot close '%s'", source);
|
|
status = -1;
|
|
}
|
|
|
|
} else if (S_ISBLK(source_stat.st_mode) || S_ISCHR(source_stat.st_mode)
|
|
|| S_ISSOCK(source_stat.st_mode) || S_ISFIFO(source_stat.st_mode)
|
|
|| S_ISLNK(source_stat.st_mode)
|
|
) {
|
|
// We are lazy here, a bit lax with races...
|
|
if (dest_exists) {
|
|
ovr = ask_and_unlink(dest, flags);
|
|
if (ovr <= 0)
|
|
return ovr;
|
|
}
|
|
if (S_ISFIFO(source_stat.st_mode)) {
|
|
if (mkfifo(dest, source_stat.st_mode) < 0) {
|
|
bb_perror_msg("cannot create fifo '%s'", dest);
|
|
return -1;
|
|
}
|
|
} else if (S_ISLNK(source_stat.st_mode)) {
|
|
char *lpath;
|
|
|
|
lpath = xmalloc_readlink_or_warn(source);
|
|
if (lpath && symlink(lpath, dest) < 0) {
|
|
bb_perror_msg("cannot create symlink '%s'", dest);
|
|
free(lpath);
|
|
return -1;
|
|
}
|
|
free(lpath);
|
|
|
|
if (flags & FILEUTILS_PRESERVE_STATUS)
|
|
if (lchown(dest, source_stat.st_uid, source_stat.st_gid) < 0)
|
|
bb_perror_msg("cannot preserve %s of '%s'", "ownership", dest);
|
|
|
|
return 0;
|
|
|
|
} else {
|
|
if (mknod(dest, source_stat.st_mode, source_stat.st_rdev) < 0) {
|
|
bb_perror_msg("cannot create '%s'", dest);
|
|
return -1;
|
|
}
|
|
}
|
|
} else {
|
|
bb_error_msg("internal error: unrecognized file type");
|
|
return -1;
|
|
}
|
|
|
|
preserve_status:
|
|
|
|
if (flags & FILEUTILS_PRESERVE_STATUS
|
|
/* Cannot happen: */
|
|
/* && !(flags & (FILEUTILS_MAKE_SOFTLINK|FILEUTILS_MAKE_HARDLINK)) */
|
|
) {
|
|
struct utimbuf times;
|
|
|
|
times.actime = source_stat.st_atime;
|
|
times.modtime = source_stat.st_mtime;
|
|
if (utime(dest, ×) < 0)
|
|
bb_perror_msg("cannot preserve %s of '%s'", "times", dest);
|
|
if (chown(dest, source_stat.st_uid, source_stat.st_gid) < 0) {
|
|
source_stat.st_mode &= ~(S_ISUID | S_ISGID);
|
|
bb_perror_msg("cannot preserve %s of '%s'", "ownership", dest);
|
|
}
|
|
if (chmod(dest, source_stat.st_mode) < 0)
|
|
bb_perror_msg("cannot preserve %s of '%s'", "permissions", dest);
|
|
}
|
|
|
|
return status;
|
|
}
|