cleaned up PF_fopen filename rejection, now rejects more unsafe names, including...

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@4182 d7cf8633-e32d-0410-b094-e92efae38249

diff --git a/pr_cmds.c b/pr_cmds.c
index fae2c4629117f9b9cc9feafa95013db0f7e6bab3..81a618190a3fc2d6a1750f8e3ceb44402f1ab514 100644 (file)
--- a/pr_cmds.c
+++ b/pr_cmds.c
@@ -2765,7 +2765,7 @@ void PF_stof(void)
 //float(string filename, float mode) fopen = #110; // opens a file inside quake/gamedir/data/ (mode is FILE_READ, FILE_APPEND, or FILE_WRITE), returns fhandle >= 0 if successful, or fhandle < 0 if unable to open file for any reason
 void PF_fopen(void)
 {
-       int filenum, mode;
+       int filenum, mode, i;
        char *modestring, *filename;
        for (filenum = 0;filenum < MAX_PRFILES;filenum++)
                if (pr_files[filenum] == NULL)
@@ -2794,15 +2794,20 @@ void PF_fopen(void)
                return;
        }
        filename = G_STRING(OFS_PARM0);
-       // .. is parent directory on many platforms
-       // / is parent directory on Amiga
+       // control characters do not cause issues with any platforms I know of, but they are usually annoying to deal with
+       // ../ is parent directory on many platforms
+       // // is parent directory on Amiga
+       // / at the beginning of a path is root on unix, and parent directory on Amiga
        // : is root of drive on Amiga (also used as a directory separator on Mac, but / works there too, so that's a bad idea)
        // \ is a windows-ism (so it's naughty to use it, / works on all platforms)
-       if ((filename[0] == '.' && filename[1] == '.') || filename[0] == '/' || strrchr(filename, ':') || strrchr(filename, '\\'))
+       for (i = 0;filename[i];i++)
        {
-               Con_Printf("PF_fopen: dangerous or non-portable filename \"%s\" not allowed. (contains : or \\ or begins with .. or /)\n", filename);
-               G_FLOAT(OFS_RETURN) = -4;
-               return;
+               if (filename[i] < ' ' || (filename[i] == '/' && filename[i+1] == '/') || (filename[i] == '.' && filename[i+1] == '.') || filename[i] == ':' || filename[i] == '\\' || filename[0] == '/')
+               {
+                       Con_Printf("PF_fopen: dangerous/confusing/annoying/non-portable filename \"%s\" not allowed. (contains control characters or // or .. or : or \\ or begins with /)\n", filename);
+                       G_FLOAT(OFS_RETURN) = -4;
+                       return;
+               }
        }
        pr_files[filenum] = FS_Open(va("data/%s", filename), modestring, false);