From 500e3225a839825f92033f9909794c55a8d0536c Mon Sep 17 00:00:00 2001
From: terrafrost <terrafrost@php.net>
Date: Fri, 17 Jan 2020 03:37:25 -0600
Subject: [PATCH] SSH2: logging enhancements

---
 phpseclib/Net/SSH2.php | 59 +++++++++++++++++++++++++-----------------
 1 file changed, 35 insertions(+), 24 deletions(-)

diff --git a/phpseclib/Net/SSH2.php b/phpseclib/Net/SSH2.php
index 6208f38c..d22786b9 100644
--- a/phpseclib/Net/SSH2.php
+++ b/phpseclib/Net/SSH2.php
@@ -1563,6 +1563,7 @@ class Net_SSH2
             if (!$this->_send_binary_packet($packet)) {
                 return false;
             }
+            $this->_updateLogHistory('UNKNOWN (34)', 'NET_SSH2_MSG_KEXDH_GEX_REQUEST');
 
             $response = $this->_get_binary_packet();
             if ($response === false) {
@@ -1578,6 +1579,7 @@ class Net_SSH2
                 user_error('Expected SSH_MSG_KEX_DH_GEX_GROUP');
                 return false;
             }
+            $this->_updateLogHistory('NET_SSH2_MSG_KEXDH_REPLY', 'NET_SSH2_MSG_KEXDH_GEX_GROUP');
 
             if (strlen($response) < 4) {
                 return false;
@@ -1666,6 +1668,9 @@ class Net_SSH2
             user_error('Connection closed by server');
             return false;
         }
+        if ($clientKexInitMessage == NET_SSH2_MSG_KEXDH_GEX_INIT) {
+            $this->_updateLogHistory('UNKNOWN (32)', 'NET_SSH2_MSG_KEXDH_GEX_INIT');
+        }
 
         $response = $this->_get_binary_packet();
         if ($response === false) {
@@ -1679,9 +1684,15 @@ class Net_SSH2
         extract(unpack('Ctype', $this->_string_shift($response, 1)));
 
         if ($type != $serverKexReplyMessage) {
-            user_error('Expected SSH_MSG_KEXDH_REPLY');
+            $expected = $serverKexReplyMessage == NET_SSH2_MSG_KEXDH_GEX_REPLY ?
+                'SSH_MSG_KEXDH_GEX_REPLY' :
+                'SSH_MSG_KEXDH_REPLY';
+            user_error("Expected $expected");
             return false;
         }
+        if ($serverKexReplyMessage == NET_SSH2_MSG_KEXDH_GEX_REPLY) {
+            $this->_updateLogHistory('UNKNOWN (33)', 'NET_SSH2_MSG_KEXDH_GEX_REPLY');
+        }
 
         if (strlen($response) < 4) {
             return false;
@@ -2316,9 +2327,7 @@ class Net_SSH2
 
         switch ($type) {
             case NET_SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ: // in theory, the password can be changed
-                if (defined('NET_SSH2_LOGGING')) {
-                    $this->message_number_log[count($this->message_number_log) - 1] = 'NET_SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ';
-                }
+                $this->_updateLogHistory('UNKNOWN (60)', 'NET_SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ');
                 if (strlen($response) < 4) {
                     return false;
                 }
@@ -2469,12 +2478,8 @@ class Net_SSH2
                 // see http://tools.ietf.org/html/rfc4256#section-3.2
                 if (strlen($this->last_interactive_response)) {
                     $this->last_interactive_response = '';
-                } elseif (defined('NET_SSH2_LOGGING')) {
-                    $this->message_number_log[count($this->message_number_log) - 1] = str_replace(
-                        'UNKNOWN',
-                        'NET_SSH2_MSG_USERAUTH_INFO_REQUEST',
-                        $this->message_number_log[count($this->message_number_log) - 1]
-                    );
+                } else {
+                    $this->_updateLogHistory('UNKNOWN (60)', 'NET_SSH2_MSG_USERAUTH_INFO_REQUEST');
                 }
 
                 if (!count($responses) && $num_prompts) {
@@ -2497,13 +2502,7 @@ class Net_SSH2
                     return false;
                 }
 
-                if (defined('NET_SSH2_LOGGING') && NET_SSH2_LOGGING == NET_SSH2_LOG_COMPLEX) {
-                    $this->message_number_log[count($this->message_number_log) - 1] = str_replace(
-                        'UNKNOWN',
-                        'NET_SSH2_MSG_USERAUTH_INFO_RESPONSE',
-                        $this->message_number_log[count($this->message_number_log) - 1]
-                    );
-                }
+                $this->_updateLogHistory('UNKNOWN (61)', 'NET_SSH2_MSG_USERAUTH_INFO_RESPONSE');
 
                 /*
                    After receiving the response, the server MUST send either an
@@ -2630,13 +2629,7 @@ class Net_SSH2
             case NET_SSH2_MSG_USERAUTH_PK_OK:
                 // we'll just take it on faith that the public key blob and the public key algorithm name are as
                 // they should be
-                if (defined('NET_SSH2_LOGGING') && NET_SSH2_LOGGING == NET_SSH2_LOG_COMPLEX) {
-                    $this->message_number_log[count($this->message_number_log) - 1] = str_replace(
-                        'UNKNOWN',
-                        'NET_SSH2_MSG_USERAUTH_PK_OK',
-                        $this->message_number_log[count($this->message_number_log) - 1]
-                    );
-                }
+                $this->_updateLogHistory('UNKNOWN (60)', 'NET_SSH2_MSG_USERAUTH_PK_OK');
         }
 
         $packet = $part1 . chr(1) . $part2;
@@ -5072,4 +5065,22 @@ class Net_SSH2
         $this->windowColumns = $columns;
         $this->windowRows = $rows;
     }
+
+    /**
+     * Update packet types in log history
+     *
+     * @param string $old
+     * @param string $new
+     * @access private
+     */
+    function _updateLogHistory($old, $new)
+    {
+        if (defined('NET_SSH2_LOGGING') && NET_SSH2_LOGGING == NET_SSH2_LOG_COMPLEX) {
+            $this->message_number_log[count($this->message_number_log) - 1] = str_replace(
+                $old,
+                $new,
+                $this->message_number_log[count($this->message_number_log) - 1]
+            );
+        }
+    }
 }