More potential buffer overflow fixes.

o Fixed `nfrontp' calculations in output_data().  If `remaining' is
  initially zero, it was possible for `nfrontp' to be decremented.

Noticed by:	dillon

o Replaced leaking writenet() with output_datalen():

:  * writenet
:  *
:  * Just a handy little function to write a bit of raw data to the net.
:  * It will force a transmit of the buffer if necessary
:  *
:  * arguments
:  *    ptr - A pointer to a character string to write
:  *    len - How many bytes to write
:  */
: 	void
: writenet(ptr, len)
: 	register unsigned char *ptr;
: 	register int len;
: {
: 	/* flush buffer if no room for new data) */
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
: 	if ((&netobuf[BUFSIZ] - nfrontp) < len) {
: 		/* if this fails, don't worry, buffer is a little big */
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
: 		netflush();
: 	}
:
: 	memmove(nfrontp, ptr, len);
: 	nfrontp += len;
:
: }  /* end of writenet */

What an irony!  :-)

o Optimized output_datalen() a bit.

1 files changed, 0 insertions, 27 deletions

diff --git a/contrib/telnet/telnetd/utility.c b/contrib/telnet/telnetd/utility.c
index aa85d7a..d59657f 100644
--- a/contrib/telnet/telnetd/utility.c
+++ b/contrib/telnet/telnetd/utility.c
@@ -318,33 +318,6 @@ netflush()
 
 
 /*
- * writenet
- *
- * Just a handy little function to write a bit of raw data to the net.
- * It will force a transmit of the buffer if necessary
- *
- * arguments
- *    ptr - A pointer to a character string to write
- *    len - How many bytes to write
- */
-	void
-writenet(ptr, len)
-	register unsigned char *ptr;
-	register int len;
-{
-	/* flush buffer if no room for new data) */
-	if ((&netobuf[BUFSIZ] - nfrontp) < len) {
-		/* if this fails, don't worry, buffer is a little big */
-		netflush();
-	}
-
-	memmove(nfrontp, ptr, len);
-	nfrontp += len;
-
-}  /* end of writenet */
-
-
-/*
  * miscellaneous functions doing a variety of little jobs follow ...
  */