rewrite telnet negotiation

1 files changed, 26 insertions, 33 deletions

diff --git a/src/usr.bin/nc/netcat.c b/src/usr.bin/nc/netcat.c
index 980f335f24..dd1e589420 100644
--- a/src/usr.bin/nc/netcat.c
+++ b/src/usr.bin/nc/netcat.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: netcat.c,v 1.23 2001/06/26 19:31:10 ericj Exp $ */
+/* $OpenBSD: netcat.c,v 1.24 2001/06/26 20:53:14 ericj Exp $ */
 /*
  * Copyright (c) 2001 Eric Jackson <ericj@monkey.org>
  *
@@ -26,9 +26,8 @@
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-/* 
- * Re-written nc(1) for OpenBSD. Only code shared with previous version
- * was the code for telnet emulation. Original implementation by
+/*
+ * Re-written nc(1) for OpenBSD. Original implementation by
  * *Hobbit* <hobbit@avian.org>.
  */
 
@@ -430,46 +429,40 @@ readwrite(nfd)
                 }
         }
 }
-
-/*
- * Answer anything that looks like telnet negotiation with don't/won't.
- * This doesn't modify any data buffers, update the global output count,
- * or show up in a hexdump -- it just shits into the outgoing stream.
- * Idea and codebase from Mudge@l0pht.com.
- */
+/* Deal with RFC854 WILL/WONT DO/DONT negotiation */
 void
 atelnet(nfd, buf, size)
         int nfd;
         unsigned char *buf;
         unsigned int size;
 {
-        static unsigned char obuf[4];
-        int x, ret;
-        unsigned char y;
-        unsigned char *p;
-
-        y = 0;
-        p = buf;
-        x = size;
-        while (x > 0) {
+        int ret, pos = 0;
+        unsigned char *p, *end;
+        unsigned char obuf[4];
+
+        end = buf + size;
+        obuf[0] = '\0';
+
+        for (p = buf; p < end; p++) {
                 if (*p != IAC)
-                        goto notiac;
-                obuf[0] = IAC;
-                p++; x--;
-                if ((*p == WILL) || (*p == WONT))
-                        y = DONT;
-                if ((*p == DO) || (*p == DONT))
-                        y = WONT;
-                if (y) {
-                        obuf[1] = y;
-                        p++; x--;
+                        break;
+
+                obuf[0]=IAC;
+                p++;
+                if ((*p == WILL) || (*p == WONT)) {
+                        obuf[1] = DONT;
+                }
+                if ((*p == DO) || (*p == DONT)) {
+                        obuf[1] = WONT;
+                }
+                if (obuf) {
+                        p++;
                         obuf[2] = *p;
+                        obuf[3] = '\0';
                         if ((ret = atomicio(write , nfd, obuf, 3)) != 3)
                                 warnx("Write Error!");
-                        y = 0;
+                        obuf[0] = '\0';
                 }
-notiac:
-                p++; x--;
         }
 }