added sudo_goodpath()

diff --git a/sudo_realpath.c b/sudo_realpath.c
index 359e524502dce16eb773b6d3a04c78336ad1e842..2eef158fabde515acf91a9d90604def0b9fe9e71 100644 (file)
--- a/sudo_realpath.c
+++ b/sudo_realpath.c
@@ -78,6 +78,41 @@ extern int lstat     __P((const char *, struct stat *));
 static void realpath_restore   __P((char *));
 
 
+/******************************************************************
+ *
+ *  sudo_goodpath()
+ *
+ *  this function takes a path and makes sure it describes a a file
+ *  that is a normal file and executable by root.
+ */
+
+char * sudo_goodpath(path)
+    const char * path;
+{
+    struct stat statbuf;               /* for stat(2) */
+    int err;                           /* if stat(2) got an error */
+
+    /* check for brain damage */
+    if (path == NULL || path[0] == '\0')
+       return(NULL);
+
+    /* we need to be root for the stat */
+    set_perms(PERM_ROOT);
+
+    err = stat(path, &statbuf);
+
+    /* discard root perms */
+    set_perms(PERM_USER);
+
+    /* make sure path describes an executable regular file */
+    if (!err && S_ISREG(statbuf.st_mode) &&(statbuf.st_mode & 0000111))
+       return(path);
+    else
+       return(NULL);
+}
+
+
+#ifdef USE_REALPATH
 /******************************************************************
  *
  *  sudo_realpath()
@@ -106,12 +141,6 @@ char * sudo_realpath(old, new)
     /* we need to be root for this section */
     set_perms(PERM_ROOT);
 
-#ifndef USE_REALPATH
-    err = stat(new, &statbuf);
-    set_perms(PERM_USER);
-    return((err == 0) ? new : NULL);
-#endif /* USE_REALPATH */
-
     /*
      * Resolve the last component of the path if it is a link
      * until it is a non-link.
@@ -216,3 +245,4 @@ static void realpath_restore(cwd)
        exit(1);
     }
 }
+#endif /* USE_REALPATH */