o [NSE] Fixed a problem in oracle-brute that would fail due to connection

exhaustion. Fixed some debugging messages in the brute library [Patrik]

CHANGELOG

@@ -1,5 +1,8 @@
 # Nmap Changelog ($Id$); -*-text-*-
 
+o [NSE] Fixed a problem in oracle-brute that would fail due to connection
+  exhaustion. Fixed some debugging messages in the brute library [Patrik]
+
 o [Ndiff] Fixed the Mac OS X packages to use the correct path for
   Python: /usr/bin/python instead of /opt/local/bin/python. The bug
   was reported by Wellington Castello. [David]

nselib/brute.lua

@@ -524,16 +524,7 @@ Engine =
 			if ( status ) then
 				-- Prevent locked accounts from appearing several times
 				if ( not(self.found_accounts) or self.found_accounts[response.username] == nil ) then
-					if ( response.username and #response.username > 0 ) then
-						stdnse.print_debug("Found valid password %s:%s on target %s", 
-							response.username, 
-							( response.password and #response.password > 0 ) and response.password or "<empty>",
-							self.host.ip )
-					else
-						stdnse.print_debug("Found valid password %s on target %s", 
-							( response.password and #response.password > 0 ) and response.password or "<empty>",
-							self.host.ip )
-					end
+					stdnse.print_debug("Discovered account: %s", response:toString())
 					table.insert( valid_accounts, response:toString() )
 					self.found_accounts[response.username] = true
 					

nselib/tns.lua

@@ -254,7 +254,7 @@ Packet.Connect = {
 				if ( tns.data:match("ERR=12514") ) then
 					return false, ("TNS: The listener could not resolve \"%s\""):format(self.dbinstance)
 				end
-				return false, "The server did not respond with an ACCEPT packet"
+				return false, tns.data:match("%(ERR=(%d*)%)")
 			end
 			
 			pos, version = bin.unpack(">S", tns.data )

scripts/oracle-brute.nse

@@ -65,15 +65,34 @@ Driver =
 	--
 	-- @return true on success, false on failure
 	connect = function( self )
-		local status, data 
+		local status, data
 		self.helper = tns.Helper:new( self.host, self.port, nmap.registry.args['oracle-brute.sid'] )
 		
-		status, data = self.helper:Connect()
-		if ( not(status) ) then
-			return status, data
-		end
+		local MAX_RETRIES = 10
+		local tries = MAX_RETRIES
 		
-		return true
+		-- This loop is intended for handling failed connections
+		-- A connection may fail for a number of different reasons.
+		-- For the moment, we're just handling the error code 12520
+		--
+		-- Error 12520 has been observed on Oracle XE and seems to
+		-- occur when a maximum connection count is reached.
+		repeat
+			if ( tries < MAX_RETRIES ) then
+				stdnse.print_debug(2, "%s: Attempting to re-connect (attempt %d of %d)", SCRIPT_NAME, MAX_RETRIES - tries, MAX_RETRIES)
+			end
+			status, data = self.helper:Connect()
+			if ( not(status) ) then
+				stdnse.print_debug(2, "%s: ERROR: An Oracle %s error occured", SCRIPT_NAME, data)
+				self.helper:Close()
+			else
+				break
+			end
+			tries = tries - 1
+			stdnse.sleep(1)
+		until( tries == 0 or data ~= "12520")
+		
+		return status, data
 	end,
 	
 	--- Attempts to login to the Oracle server