Add a new bug-compatibility mode that limits the window size we'll

[u/mdw/putty] / ssh.c

diff --git a/ssh.c b/ssh.c
index a4b78c4..eec0580 100644 (file)
--- a/ssh.c
+++ b/ssh.c
@@ -183,6 +183,7 @@ static const char *const ssh2_disconnect_reasons[] = {
 #define BUG_SSH2_DERIVEKEY                       32
 #define BUG_SSH2_REKEY                           64
 #define BUG_SSH2_PK_SESSIONID                   128
+#define BUG_SSH2_MAXPKT                                256
 
 /*
  * Codes for terminal modes.
@@ -2391,6 +2392,16 @@ static void ssh_detect_bugs(Ssh ssh, char *vstring)
        ssh->remote_bugs |= BUG_SSH2_REKEY;
        logevent("We believe remote version has SSH-2 rekey bug");
     }
+
+    if (ssh->cfg.sshbug_maxpkt2 == FORCE_ON ||
+       (ssh->cfg.sshbug_maxpkt2 == AUTO &&
+        (wc_match("1.36_sshlib GlobalSCAPE", imp)))) {
+       /*
+        * This version ignores our makpkt and needs to be throttled.
+        */
+       ssh->remote_bugs |= BUG_SSH2_MAXPKT;
+       logevent("We believe remote version ignores SSH-2 maximum packet size");
+    }
 }
 
 /*
@@ -6236,6 +6247,15 @@ static void ssh2_set_window(struct ssh_channel *c, int newwin)
        return;
 
     /*
+     * If the remote end has a habit of ignoring maxpkt, limit the
+     * window so that it has no choice (assuming it doesn't ignore the
+     * window as well).
+     */
+    if ((ssh->remote_bugs & BUG_SSH2_MAXPKT) && newwin > OUR_V2_MAXPKT)
+       newwin = OUR_V2_MAXPKT;
+       
+
+    /*
      * Only send a WINDOW_ADJUST if there's significantly more window
      * available than the other end thinks there is.  This saves us
      * sending a WINDOW_ADJUST for every character in a shell session.