Adding the --fake-super option.

1 files changed, 56 insertions, 2 deletions

diff --git a/tls.c b/tls.c
index cd4e26de..8a388199 100644
--- a/tls.c
+++ b/tls.c
@@ -34,15 +34,65 @@
  * change. */
 
 #include "rsync.h"
+#include "lib/sysxattrs.h"
 
 #define PROGRAM "tls"
 
 /* These are to make syscall.o shut up. */
 int dry_run = 0;
+int am_root = 0;
 int read_only = 1;
 int list_only = 0;
 int preserve_perms = 0;
 
+#ifdef HAVE_LINUX_XATTRS
+#define XSTAT_ATTR "user.rsync.%stat"
+#else
+#define XSTAT_ATTR "rsync.%stat"
+#endif
+
+static int stat_xattr(const char *fname, STRUCT_STAT *fst)
+{
+	int mode, rdev_major, rdev_minor, uid, gid, len;
+	char buf[256];
+
+	if (am_root >= 0 || IS_DEVICE(fst->st_mode) || IS_SPECIAL(fst->st_mode))
+		return -1;
+
+	len = sys_lgetxattr(fname, XSTAT_ATTR, buf, sizeof buf - 1);
+	if (len >= (int)sizeof buf) {
+		len = -1;
+		errno = ERANGE;
+	}
+	if (len < 0) {
+		if (errno == ENOTSUP || errno == ENOATTR)
+			return -1;
+		if (errno == EPERM && S_ISLNK(fst->st_mode)) {
+			fst->st_uid = 0;
+			fst->st_gid = 0;
+			return 0;
+		}
+		fprintf(stderr, "failed to read xattr %s for %s: %s\n",
+			XSTAT_ATTR, fname, strerror(errno));
+		return -1;
+	}
+	buf[len] = '\0';
+
+	if (sscanf(buf, "%o %d,%d %d:%d",
+		   &mode, &rdev_major, &rdev_minor, &uid, &gid) != 5) {
+		fprintf(stderr, "Corrupt %s xattr attached to %s: \"%s\"\n",
+			XSTAT_ATTR, fname, buf);
+		exit(1);
+	}
+
+	fst->st_mode = from_wire_mode(mode);
+	fst->st_rdev = MAKEDEV(rdev_major, rdev_minor);
+	fst->st_uid = uid;
+	fst->st_gid = gid;
+
+	return 0;
+}
+
 static void failed(char const *what, char const *where)
 {
 	fprintf(stderr, PROGRAM ": %s %s: %s\n",
@@ -60,6 +110,8 @@ static void list_file(const char *fname)
 
 	if (do_lstat(fname, &buf) < 0)
 		failed("stat", fname);
+	if (am_root < 0)
+		stat_xattr(fname, &buf);
 
 	/* The size of anything but a regular file is probably not
 	 * worth thinking about. */
@@ -125,9 +177,11 @@ main(int argc, char *argv[])
 		return 1;
 	}
 
-	for (argv++; *argv; argv++) {
+	if (getenv("RSYNC_FAKE_SUPER"))
+		am_root = -1;
+
+	for (argv++; *argv; argv++)
 		list_file(*argv);
-	}
 
 	return 0;
 }