* 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.
- *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
-
#include "libbb.h"
+// FEATURE_NON_POSIX_CP:
+//
// 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!
+// If dest is a (sym)link, we overwrite link 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...
-//
-// NB: we have special code which still allows for "cp file /dev/node"
-// to work POSIX-ly (the only realistic case where it makes sense)
-#define DO_POSIX_CP 0 /* 1 - POSIX behavior, 0 - safe behavior */
-
-// errno must be set to relevant value ("why we cannot create dest?")
-// for POSIX mode to give reasonable error message
+/* Called if open of destination, link creation etc fails.
+ * errno must be set to relevant value ("why we cannot create dest?")
+ * to give reasonable error message */
static int ask_and_unlink(const char *dest, int flags)
{
int e = errno;
-#if DO_POSIX_CP
+
+#if !ENABLE_FEATURE_NON_POSIX_CP
if (!(flags & (FILEUTILS_FORCE|FILEUTILS_INTERACTIVE))) {
- // Either it exists, or the *path* doesnt exist
- bb_perror_msg("cannot create '%s'", dest);
+ /* Either it exists, or the *path* doesnt exist */
+ bb_perror_msg("can't create '%s'", dest);
return -1;
}
#endif
- // If !DO_POSIX_CP, act as if -f is always in effect - we don't want
- // "cannot create" msg, we want unlink to be done (silently unless -i).
+ // else: act as if -f is always in effect.
+ // We don't want "can't create" msg, we want unlink to be done
+ // (silently unless -i). Why? POSIX cp usually succeeds with
+ // O_TRUNC open of existing file, and user is left ignorantly happy.
+ // With above block unconditionally enabled, non-POSIX cp
+ // will complain a lot more than POSIX one.
- // TODO: maybe we should do it only if ctty is present?
+ /* 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 "unlink 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 (!bb_ask_y_confirmation())
+ return 0; /* not allowed to overwrite */
}
if (unlink(dest) < 0) {
#if ENABLE_FEATURE_VERBOSE_CP_MESSAGE
if (e == errno && e == ENOENT) {
/* e == ENOTDIR is similar: path has non-dir component,
* but in this case we don't even reach copy_file() */
- bb_error_msg("cannot create '%s': Path does not exist", dest);
- return -1; // error
+ bb_error_msg("can't create '%s': Path does not exist", dest);
+ return -1; /* error */
}
#endif
- errno = e;
- bb_perror_msg("cannot create '%s'", dest);
- return -1; // error
+ errno = e; /* do not use errno from unlink */
+ bb_perror_msg("can't create '%s'", dest);
+ return -1; /* error */
}
- return 1; // ok (to try again)
+#if ENABLE_FEATURE_CP_LONG_OPTIONS
+ if (flags & FILEUTILS_RMDEST)
+ if (flags & FILEUTILS_VERBOSE)
+ printf("removed '%s'\n", dest);
+#endif
+ return 1; /* ok (to try again) */
}
/* Return:
* 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)
+int FAST_FUNC copy_file(const char *source, const char *dest, int flags)
{
/* This is a recursive function, try to minimize stack usage */
/* NB: each struct stat is ~100 bytes */
struct stat source_stat;
struct stat dest_stat;
- signed char retval = 0;
- signed char dest_exists = 0;
- signed char ovr;
+ smallint retval = 0;
+ smallint dest_exists = 0;
+ smallint ovr;
-#define FLAGS_DEREF (flags & FILEUTILS_DEREFERENCE)
+/* Inverse of cp -d ("cp without -d") */
+#define FLAGS_DEREF (flags & (FILEUTILS_DEREFERENCE + FILEUTILS_DEREFERENCE_L0))
if ((FLAGS_DEREF ? stat : lstat)(source, &source_stat) < 0) {
- // This may be a dangling symlink.
- // Making [sym]links to dangling symlinks works, so...
+ /* 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);
+ bb_perror_msg("can't stat '%s'", source);
return -1;
}
if (lstat(dest, &dest_stat) < 0) {
if (errno != ENOENT) {
- bb_perror_msg("cannot stat '%s'", dest);
+ bb_perror_msg("can't stat '%s'", dest);
return -1;
}
} else {
security_context_t con;
if (lgetfilecon(source, &con) >= 0) {
if (setfscreatecon(con) < 0) {
- bb_perror_msg("cannot set setfscreatecon %s", con);
+ bb_perror_msg("can't 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);
+ bb_perror_msg("can't lgetfilecon %s", source);
return -1;
}
}
return -1;
}
- /* Create DEST */
if (dest_exists) {
if (!S_ISDIR(dest_stat.st_mode)) {
bb_error_msg("target '%s' is not a directory", dest);
/* race here: user can substitute a symlink between
* this check and actual creation of files inside dest */
} else {
+ /* Create DEST */
mode_t mode;
saved_umask = umask(0);
mode |= S_IRWXU;
if (mkdir(dest, mode) < 0) {
umask(saved_umask);
- bb_perror_msg("cannot create directory '%s'", dest);
+ bb_perror_msg("can't create directory '%s'", dest);
return -1;
}
umask(saved_umask);
/* need stat info for add_to_ino_dev_hashtable */
if (lstat(dest, &dest_stat) < 0) {
- bb_perror_msg("cannot stat '%s'", dest);
+ bb_perror_msg("can't stat '%s'", dest);
return -1;
}
}
if (new_source == NULL)
continue;
new_dest = concat_path_file(dest, d->d_name);
- if (copy_file(new_source, new_dest, flags) < 0)
+ if (copy_file(new_source, new_dest, flags & ~FILEUTILS_DEREFERENCE_L0) < 0)
retval = -1;
free(new_source);
free(new_dest);
if (!dest_exists
&& chmod(dest, source_stat.st_mode & ~saved_umask) < 0
) {
- bb_perror_msg("cannot preserve %s of '%s'", "permissions", dest);
+ bb_perror_msg("can't preserve %s of '%s'", "permissions", dest);
/* retval = -1; - WRONG! copy *WAS* made */
}
goto preserve_mode_ugid_time;
}
+ if (dest_exists) {
+ if (flags & FILEUTILS_UPDATE) {
+ if (source_stat.st_mtime <= dest_stat.st_mtime) {
+ return 0; /* source file must be newer */
+ }
+ }
+#if ENABLE_FEATURE_CP_LONG_OPTIONS
+ if (flags & FILEUTILS_RMDEST) {
+ ovr = ask_and_unlink(dest, flags);
+ if (ovr <= 0)
+ return ovr;
+ dest_exists = 0;
+ }
+#endif
+ }
+
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...)
+ /* 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);
+ bb_perror_msg("can't create link '%s'", dest);
return -1;
}
}
/* _Not_ jumping to preserve_mode_ugid_time:
- * hard/softlinks don't have those */
+ * (sym)links don't have those */
return 0;
}
- if (S_ISREG(source_stat.st_mode)
- /* DEREF uses stat, which never returns S_ISLNK() == true. */
+ if (/* "cp thing1 thing2" without -R: just open and read() from thing1 */
+ !(flags & FILEUTILS_RECUR)
+ /* "cp [-opts] regular_file thing2" */
+ || S_ISREG(source_stat.st_mode)
+ /* DEREF uses stat, which never returns S_ISLNK() == true.
+ * So the below is never true: */
/* || (FLAGS_DEREF && S_ISLNK(source_stat.st_mode)) */
) {
int src_fd;
int dst_fd;
+ mode_t new_mode;
+
+ if (!FLAGS_DEREF && S_ISLNK(source_stat.st_mode)) {
+ /* "cp -d symlink dst": create a link */
+ goto dont_cat;
+ }
if (ENABLE_FEATURE_PRESERVE_HARDLINKS && !FLAGS_DEREF) {
const char *link_target;
if (ovr <= 0)
return ovr;
if (link(link_target, dest) < 0) {
- bb_perror_msg("cannot create link '%s'", dest);
+ bb_perror_msg("can't create link '%s'", dest);
return -1;
}
}
if (src_fd < 0)
return -1;
- /* POSIX way is a security problem versus symlink attacks,
- * we do it only for non-symlinks, and only for non-recursive,
- * non-interactive cp. NB: it is still racy
- * for "cp file /home/bad_user/file" case
- * (user can rm file and create a link to /etc/passwd) */
- if (DO_POSIX_CP
- || (dest_exists && !(flags & (FILEUTILS_RECUR|FILEUTILS_INTERACTIVE))
- && !S_ISLNK(dest_stat.st_mode))
- ) {
- dst_fd = open(dest, 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);
+ /* Do not try to open with weird mode fields */
+ new_mode = source_stat.st_mode;
+ if (!S_ISREG(source_stat.st_mode))
+ new_mode = 0666;
+
+ if (ENABLE_FEATURE_NON_POSIX_CP || (flags & FILEUTILS_INTERACTIVE)) {
+ /*
+ * O_CREAT|O_EXCL: require that file did not exist before creation
+ */
+ dst_fd = open(dest, O_WRONLY|O_CREAT|O_EXCL, new_mode);
+ } else { /* POSIX, and not "cp -i" */
+ /*
+ * O_CREAT|O_TRUNC: create, or truncate (security problem versus (sym)link attacks)
+ */
+ dst_fd = open(dest, O_WRONLY|O_CREAT|O_TRUNC, new_mode);
+ }
if (dst_fd == -1) {
ovr = ask_and_unlink(dest, flags);
if (ovr <= 0) {
return ovr;
}
/* It shouldn't exist. If it exists, do not open (symlink attack?) */
- dst_fd = open3_or_warn(dest, O_WRONLY|O_CREAT|O_EXCL, source_stat.st_mode);
+ dst_fd = open3_or_warn(dest, O_WRONLY|O_CREAT|O_EXCL, new_mode);
if (dst_fd < 0) {
close(src_fd);
return -1;
}
#if ENABLE_SELINUX
- if (((flags & FILEUTILS_PRESERVE_SECURITY_CONTEXT)
- || (flags & FILEUTILS_SET_SECURITY_CONTEXT))
+ if ((flags & (FILEUTILS_PRESERVE_SECURITY_CONTEXT|FILEUTILS_SET_SECURITY_CONTEXT))
&& is_selinux_enabled() > 0
) {
security_context_t con;
if (getfscreatecon(&con) == -1) {
- bb_perror_msg("getfscreatecon");
+ bb_simple_perror_msg("getfscreatecon");
return -1;
}
if (con) {
freecon(con);
}
}
+#endif
+#if ENABLE_FEATURE_CP_REFLINK
+# undef BTRFS_IOCTL_MAGIC
+# define BTRFS_IOCTL_MAGIC 0x94
+# undef BTRFS_IOC_CLONE
+# define BTRFS_IOC_CLONE _IOW (BTRFS_IOCTL_MAGIC, 9, int)
+ if (flags & FILEUTILS_REFLINK) {
+ retval = ioctl(dst_fd, BTRFS_IOC_CLONE, src_fd);
+ if (retval == 0)
+ goto do_close;
+ /* reflink did not work */
+ if (flags & FILEUTILS_REFLINK_ALWAYS) {
+ bb_perror_msg("failed to clone '%s' from '%s'", dest, source);
+ goto do_close;
+ }
+ /* fall through to standard copy */
+ retval = 0;
+ }
#endif
if (bb_copyfd_eof(src_fd, dst_fd) == -1)
retval = -1;
- /* Ok, writing side I can understand... */
+ IF_FEATURE_CP_REFLINK(do_close:)
+ /* Careful with writing... */
if (close(dst_fd) < 0) {
- bb_perror_msg("cannot close '%s'", dest);
+ bb_perror_msg("error writing to '%s'", dest);
retval = -1;
}
/* ...but read size is already checked by bb_copyfd_eof */
close(src_fd);
+ /* "cp /dev/something new_file" should not
+ * copy mode of /dev/something */
+ if (!S_ISREG(source_stat.st_mode))
+ return retval;
goto preserve_mode_ugid_time;
}
+ dont_cat:
/* Source is a symlink or a special file */
/* We are lazy here, a bit lax with races... */
char *lpath = xmalloc_readlink_or_warn(source);
if (lpath) {
int r = symlink(lpath, dest);
- free(lpath);
if (r < 0) {
- bb_perror_msg("cannot create symlink '%s'", dest);
+ /* shared message */
+ bb_perror_msg("can't create %slink '%s' to '%s'",
+ "sym", dest, lpath
+ );
+ 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);
+ bb_perror_msg("can't preserve %s of '%s'", "ownership", dest);
}
/* _Not_ jumping to preserve_mode_ugid_time:
* symlinks don't have those */
- return 0;
+ goto verb_and_exit;
}
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)
) {
if (mknod(dest, source_stat.st_mode, source_stat.st_rdev) < 0) {
- bb_perror_msg("cannot create '%s'", dest);
+ bb_perror_msg("can't create '%s'", dest);
return -1;
}
} else {
/* Cannot happen: */
/* && !(flags & (FILEUTILS_MAKE_SOFTLINK|FILEUTILS_MAKE_HARDLINK)) */
) {
- struct utimbuf times;
+ struct timeval times[2];
- times.actime = source_stat.st_atime;
- times.modtime = source_stat.st_mtime;
+ times[1].tv_sec = times[0].tv_sec = source_stat.st_mtime;
+ times[1].tv_usec = times[0].tv_usec = 0;
/* BTW, utimes sets usec-precision time - just FYI */
- if (utime(dest, ×) < 0)
- bb_perror_msg("cannot preserve %s of '%s'", "times", dest);
+ if (utimes(dest, times) < 0)
+ bb_perror_msg("can't 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);
+ bb_perror_msg("can't preserve %s of '%s'", "ownership", dest);
}
if (chmod(dest, source_stat.st_mode) < 0)
- bb_perror_msg("cannot preserve %s of '%s'", "permissions", dest);
+ bb_perror_msg("can't preserve %s of '%s'", "permissions", dest);
+ }
+
+ verb_and_exit:
+ if (flags & FILEUTILS_VERBOSE) {
+ printf("'%s' -> '%s'\n", source, dest);
}
return retval;
projects / oweals / busybox.git / blobdiff