bin/127194: [PATCH] arpa/telnet.h: TELOPT(x) returns wrong result / segfaults

[Joost Bekkers]

>Number:         127194
>Category:       bin
>Synopsis:       [PATCH] arpa/telnet.h: TELOPT(x) returns wrong result / segfaults
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sun Sep 07 20:40:02 UTC 2008
>Closed-Date:
>Last-Modified:
>Originator:     Joost Bekkers
>Release:        FreeBSD 7.0-RELEASE-p4 amd64
>Organization:
>Environment:
System: FreeBSD bps.jodocus.org 7.0-RELEASE-p4 FreeBSD 7.0-RELEASE-p4 #3: Wed Sep 3 23:33:23 CEST 2008 joost at bps.jodocus.org:/usr/src/sys/amd64/compile/bps amd64


>Description:

The telnet options added to src/contrib/telnet/arpa/telnet.h in rev
1.9 (==RELENG_5_2_0_RELEASE==HEAD) were discontinuous, but names
were added to telopts[] without the corresponding gaps. This can cause
TELOPT to return pointers outside of telopts[] even though TELOPT_OK
returns 'true'.



>How-To-Repeat:

#include <stdio.h>
#define TELOPTS
#include <arpa/telnet.h>

int main(int argc,char *argv[]) {
  unsigned int opt;

  opt=TELOPT_KERMIT;
  if (TELOPT_OK(opt)) 
    printf("Option name:%s\n",TELOPT(opt));
  else
    printf("Unknown option %d\n",opt);
  return 0;
}

depending on your luck, this either tells you the option is "(null)" or segfaults.

>Fix:

--- telnet.h.org        2008-09-07 21:45:53.000000000 +0200
+++ telnet.h    2008-09-07 22:12:19.000000000 +0200
@@ -140,8 +140,8 @@
        "TACACS UID", "OUTPUT MARKING", "TTYLOC",
        "3270 REGIME", "X.3 PAD", "NAWS", "TSPEED", "LFLOW",
        "LINEMODE", "XDISPLOC", "OLD-ENVIRON", "AUTHENTICATION",
-       "ENCRYPT", "NEW-ENVIRON", "TN3270E", "CHARSET", "COM-PORT",
-       "KERMIT",
+       "ENCRYPT", "NEW-ENVIRON", "TN3270E", "XAUTH", "CHARSET",
+       "RSP", "COM-PORT", "SLE", "STARTTLS", "KERMIT",
        0
 };
 #define        TELOPT_FIRST    TELOPT_BINARY


>Release-Note:
>Audit-Trail:
>Unformatted: