# HG changeset patch
# User Kim Alvefur <zash@zash.se>
# Date 1584894926 -3600
# Node ID fd77b6cec38db737a6987168bcc0b20f33949254
# Parent  27d15097c23540316b4a27c45821cf98a1106860
mod_admin_telnet: Handle unavailable cipher info (fixes #1510)

The LuaSec :info() method gathers info using the OpenSSL function
SSL_get_current_cipher(). Documentation for this function states that it
may return NULL if no session has been established (yet). If so, the
LuaSec functions wrapping this return nil, triggering a nil-indexing
error in mod_admin_telnet.

diff -r 27d15097c235 -r fd77b6cec38d plugins/mod_admin_telnet.lua
--- a/plugins/mod_admin_telnet.lua	Thu Mar 12 20:32:07 2020 +0000
+++ b/plugins/mod_admin_telnet.lua	Sun Mar 22 17:35:26 2020 +0100
@@ -528,11 +528,14 @@
 	common_info(session, line);
 	if session.secure then
 		local sock = session.conn and session.conn.socket and session.conn:socket();
-		if sock and sock.info then
-			local info = sock:info();
-			line[#line+1] = ("(%s with %s)"):format(info.protocol, info.cipher);
-		else
-			line[#line+1] = "(cipher info unavailable)";
+		if sock then
+			local info = sock.info and sock:info();
+			if info then
+				line[#line+1] = ("(%s with %s)"):format(info.protocol, info.cipher);
+			else
+				-- TLS session might not be ready yet
+				line[#line+1] = "(cipher info unavailable)";
+			end
 		end
 	else
 		line[#line+1] = "(insecure)";