[src/trunk]: src/libexec/telnetd (scrub_env): change to only accept a listed ...

[assar <assar%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/39a18cda0570
branches:  trunk
changeset: 500252:39a18cda0570
user:      assar <assar%NetBSD.org@localhost>
date:      Sat Dec 09 00:50:21 2000 +0000

description:
(scrub_env): change to only accept a listed set of variables,
including only non-filename contents for TERMCAP

diffstat:

 libexec/telnetd/sys_term.c |  59 +++++++++++++++++++++++++++++----------------
 1 files changed, 38 insertions(+), 21 deletions(-)

diffs (88 lines):

diff -r fa6f4008936b -r 39a18cda0570 libexec/telnetd/sys_term.c
--- a/libexec/telnetd/sys_term.c        Sat Dec 09 00:47:57 2000 +0000
+++ b/libexec/telnetd/sys_term.c        Sat Dec 09 00:50:21 2000 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: sys_term.c,v 1.19 2000/11/19 20:17:39 christos Exp $   */
+/*     $NetBSD: sys_term.c,v 1.20 2000/12/09 00:50:21 assar Exp $      */
 
 /*
  * Copyright (c) 1989, 1993
@@ -38,7 +38,7 @@
 #if 0
 static char sccsid[] = "@(#)sys_term.c 8.4+1 (Berkeley) 5/30/95";
 #else
-__RCSID("$NetBSD: sys_term.c,v 1.19 2000/11/19 20:17:39 christos Exp $");
+__RCSID("$NetBSD: sys_term.c,v 1.20 2000/12/09 00:50:21 assar Exp $");
 #endif
 #endif /* not lint */
 
@@ -1882,33 +1882,50 @@
 /*
  * scrub_env()
  *
- * Remove a few things from the environment that
- * don't need to be there.
+ * We only accept the environment variables listed below.
  */
+
 void
 scrub_env()
 {
-       register char **cpp, **cpp2;
+       static const char *reject[] = {
+               "TERMCAP=/",
+               NULL
+       };
+
+       static const char *accept[] = {
+               "XAUTH=", "XAUTHORITY=", "DISPLAY=",
+               "TERM=",
+               "EDITOR=",
+               "PAGER=",
+               "LOGNAME=",
+               "POSIXLY_CORRECT=",
+               "TERMCAP=",
+               "PRINTER=",
+               NULL
+       };
+
+       char **cpp, **cpp2;
+       const char **p;
 
        for (cpp2 = cpp = environ; *cpp; cpp++) {
-               if (strncmp(*cpp, "LD_", 3) &&
-                   strncmp(*cpp, "_RLD_", 5) &&
-                   strncmp(*cpp, "LIBPATH=", 8) &&
-                   strncmp(*cpp, "LOCALDOMAIN=", 12) &&
-                   strncmp(*cpp, "RES_OPTIONS=", 12) &&
-                   strncmp(*cpp, "TERMINFO=", 9) &&
-                   strncmp(*cpp, "TERMINFO_DIRS=", 14) &&
-                   /*
-                    * We dissallow TERMPATH and TERMCAP
-                    * entries that reference files.
-                    */
-                   strncmp(*cpp, "TERMPATH=", 9) &&
-                   strncmp(*cpp, "TERMCAP=/", 9) &&
-                   strncmp(*cpp, "ENV=", 4) &&
-                   strncmp(*cpp, "IFS=", 4))
+               int reject_it = 0;
+
+               for(p = reject; *p; p++)
+                       if(strncmp(*cpp, *p, strlen(*p)) == 0) {
+                               reject_it = 1;
+                               break;
+                       }
+               if (reject_it)
+                       continue;
+
+               for(p = accept; *p; p++)
+                       if(strncmp(*cpp, *p, strlen(*p)) == 0)
+                               break;
+               if(*p != NULL)
                        *cpp2++ = *cpp;
        }
-       *cpp2 = 0;
+       *cpp2 = NULL;
 }
 
 /*