From 7b67aaea5d6c58916d30cc1552cb5f06f9cbdae1 Mon Sep 17 00:00:00 2001
From: bigbael <bigbael@users.noreply.github.com>
Date: Sun, 22 Dec 2019 18:17:04 -0600
Subject: [PATCH 1/2] smb.lua: Add SMB argument smbnativeos, which will
 override the default setting of 'Nmap' for 'Native OS'.

Add new SMB argument, smbnativeos
If set, this will override the default hard-coded value of Nmap
---
 nselib/smb.lua | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/nselib/smb.lua b/nselib/smb.lua
index 3931777cd..43e68b003 100644
--- a/nselib/smb.lua
+++ b/nselib/smb.lua
@@ -117,6 +117,7 @@
 --                   to be the same protocol as port 445, not port 139. Since it probably isn't possible to change
 --                   Windows' ports normally, this is mostly useful if you're bouncing through a relay or something.
 -- @args randomseed   Set to a value to change the filenames/service names that are randomly generated.
+-- @args smbnativeos	Set the value of "Native OS", if not set, defaults to "Nmap".
 --
 -- @author Ron Bowes <ron@skullsecurity.net>
 -- @copyright Same as Nmap--See https://nmap.org/book/man-legal.html
@@ -1143,6 +1144,7 @@ local function start_session_basic(smb, log_errors, overrides)
   local os, lanmanager
   local username, domain, password, password_hash, hash_type
   local busy_count = 0
+  local nativeos
 
   header = smb_encode_header(smb, command_codes['SMB_COM_SESSION_SETUP_ANDX'], overrides)
 
@@ -1158,6 +1160,13 @@ local function start_session_basic(smb, log_errors, overrides)
     result, username, domain, password, password_hash, hash_type = smbauth.get_account(smb['host'])
   end
 
+  -- Get the value of Native OS or set to default
+  if (nmap.registry.args.smbnativeos ~= nil) then
+	nativeos = nmap.registry.args.smbnativeos
+  else
+	nativeos = "Nmap"
+  end
+  
   while result ~= false do
     local lanman, ntlm
 
@@ -1184,7 +1193,7 @@ local function start_session_basic(smb, log_errors, overrides)
     .. string.pack("<zzzz",
       username,               -- Account
       domain,                 -- Domain
-      "Nmap",                 -- OS
+	  nativeos,               -- OS
       "Native Lanman"         -- Native LAN Manager
       )
 
@@ -1302,6 +1311,7 @@ local function start_session_extended(smb, log_errors, overrides)
   local os, lanmanager
   local username, domain, password, password_hash, hash_type
   local busy_count = 0
+  local nativeos
 
   -- Set a default status_name, in case everything fails
   status_name = "An unknown error has occurred"
@@ -1320,6 +1330,13 @@ local function start_session_extended(smb, log_errors, overrides)
       return result, username
     end
   end
+  
+  -- Get the value of Native OS or set to default
+  if (nmap.registry.args.smbnativeos ~= nil) then
+	nativeos = nmap.registry.args.smbnativeos
+  else
+	nativeos = "Nmap"
+  end
 
   -- check what kind of security blob we were given in the negotiate protocol request
   local sp_nego = false
@@ -1383,7 +1400,7 @@ local function start_session_extended(smb, log_errors, overrides)
       -- Data is a list of strings, terminated by a blank one.
       data = security_blob -- Security blob
       .. string.pack("<zzz",
-        "Nmap",                -- OS
+        nativeos,              -- OS
         "Native Lanman",       -- Native LAN Manager
         ""                     -- Primary domain
         )

From 2aa4025f09aa894c8b25d2ab6c0e8c438744e23f Mon Sep 17 00:00:00 2001
From: bigbael <bigbael@users.noreply.github.com>
Date: Sun, 22 Dec 2019 21:17:50 -0600
Subject: [PATCH 2/2] Update smb.lua

---
 nselib/smb.lua | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/nselib/smb.lua b/nselib/smb.lua
index 43e68b003..dae9727cc 100644
--- a/nselib/smb.lua
+++ b/nselib/smb.lua
@@ -1162,9 +1162,9 @@ local function start_session_basic(smb, log_errors, overrides)
 
   -- Get the value of Native OS or set to default
   if (nmap.registry.args.smbnativeos ~= nil) then
-	nativeos = nmap.registry.args.smbnativeos
+    nativeos = nmap.registry.args.smbnativeos
   else
-	nativeos = "Nmap"
+    nativeos = "Nmap"
   end
   
   while result ~= false do
@@ -1333,9 +1333,9 @@ local function start_session_extended(smb, log_errors, overrides)
   
   -- Get the value of Native OS or set to default
   if (nmap.registry.args.smbnativeos ~= nil) then
-	nativeos = nmap.registry.args.smbnativeos
+    nativeos = nmap.registry.args.smbnativeos
   else
-	nativeos = "Nmap"
+    nativeos = "Nmap"
   end
 
   -- check what kind of security blob we were given in the negotiate protocol request