From 60af9eae092b2f3ab64b4e6b1effb7496d3bde4e Mon Sep 17 00:00:00 2001
From: Tony Garnock-Jones <tonyg@leastfixedpoint.com>
Date: Sat, 19 Jun 2021 15:12:39 +0200
Subject: [PATCH] Timeout waiting for identification line

---
 syndicate-ssh/new-server.rkt    | 6 ++++--
 syndicate-ssh/ssh-transport.rkt | 9 ++++++++-
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/syndicate-ssh/new-server.rkt b/syndicate-ssh/new-server.rkt
index 1d6707d..e2ec9d5 100644
--- a/syndicate-ssh/new-server.rkt
+++ b/syndicate-ssh/new-server.rkt
@@ -44,8 +44,10 @@
 
     (define local-identification #"SSH-2.0-RacketSSH_0.0")
 
-    (spawn #:name 'reader (ssh-reader conn-ds source))
-    (spawn #:name 'writer (ssh-writer conn-ds sink local-identification))
+    (spawn/link #:name 'reader (ssh-reader conn-ds ground-ds source))
+    (spawn/link #:name 'writer (ssh-writer conn-ds sink local-identification))
+
+    (on-stop (stop-actor-system))
 
     (at conn-ds
       (once
diff --git a/syndicate-ssh/ssh-transport.rkt b/syndicate-ssh/ssh-transport.rkt
index 9e3351b..0170c46 100644
--- a/syndicate-ssh/ssh-transport.rkt
+++ b/syndicate-ssh/ssh-transport.rkt
@@ -15,6 +15,7 @@
 	 ssh-writer)
 
 (require bitsyntax)
+(require syndicate/drivers/timer)
 (require syndicate/drivers/tcp)
 
 (require "crypto.rkt")
@@ -260,7 +261,7 @@
 ;; Encrypted Packet Input
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
-(define (ssh-reader conn-ds source)
+(define (ssh-reader conn-ds ground-ds source)
   (define input-handler #f)
   (define (update-input-handler #:on-data proc) (set! input-handler proc))
   (make-sink #:initial-source source
@@ -271,7 +272,13 @@
   (update-input-handler
    #:on-data (lambda (remote-identification _mode)
                (send! conn-ds (ssh-identification-line remote-identification))
+               (stop-facet identification-line-timeout-facet)
                (update-input-handler #:on-data handle-packet-header)))
+  (define identification-line-timeout-facet
+    (at ground-ds
+      (once [(timeout 10000)
+             (log-info "Timeout waiting for remote-identification")
+             (stop-current-facet)])))
 
   (define packet-size-limit (default-packet-limit))
   (define sequence-number 0)