+
−# This Source Code Form is subject to the terms of the Mozilla Public
+
−# License, v. 2.0.  If a copy of the MPL was not distributed with this
+
−# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
−#
+
−# Copyright 1997 - July 2008 CWI, August 2008 - 2020 MonetDB B.V.
+
−
+
−# Implements the MAPI communication protocol
+
−
+
−
+
−require 'socket'
+
−require 'time'
+
−require_relative 'hasher'
+
−require_relative 'MonetDBExceptions'
+
−require 'uri'   # parse merovingian redirects
+
−
+
−class MonetDBConnection
+
−	Q_TABLE               = "1" # SELECT operation
+
−	Q_UPDATE              = "2" # INSERT/UPDATE operations
+
−	Q_CREATE              = "3" # CREATE/DROP TABLE operations
+
−	Q_TRANSACTION         = "4" # TRANSACTION
+
−	Q_PREPARE             = "5"
+
−	Q_BLOCK               = "6" # QBLOCK message
+
−
+
−	MSG_REDIRECT          = '^' # auth redirection through merovingian
+
−	MSG_QUERY             = '&'
+
−	MSG_SCHEMA_HEADER     = '%'
+
−	MSG_INFO              = '!' # info response from mserver
+
−	MSG_TUPLE             = '['
+
−	MSG_PROMPT            =  ""
+
−
+
−
+
−	REPLY_SIZE            = '-1'
+
−
+
−	MAX_AUTH_ITERATION    = 10  # maximum number of auth iterations (through merovingian) allowed
+
−
+
−	MONET_ERROR           = -1
+
−
+
−	LANG_SQL = "sql"
+
−
+
−	# Protocols
+
−	MAPIv9 = 9
+
−
+
−	MONETDB_MEROVINGIAN = "merovingian"
+
−	MONETDB_MSERVER     = "monetdb"
+
−
+
−	MEROVINGIAN_MAX_ITERATIONS = 10
+
−
+
−
+
−	# enable debug output
+
−	@@DEBUG               = false
+
−
+
−	# hour in seconds, used for timezone calculation
+
−	@@HOUR                = 3600
+
−
+
−	# maximum size (in bytes) for a monetdb message to be sent
+
−	@@MAX_MESSAGE_SIZE    = 8190
+
−
+
−	# endianness of a message sent to the server
+
−	@@CLIENT_ENDIANNESS   = "BIG"
+
−
+
−	# MAPI protocols supported by the driver
+
−	@@SUPPORTED_PROTOCOLS = [ MonetDBConnection::MAPIv9 ]
+
−
+
−	attr_reader :socket, :auto_commit, :transactions, :lang
+
−
+
−	# Instantiates a new MonetDBConnection object
+
−	# * user: username (default is monetdb)
+
−	# * passwd: password (default is monetdb)
+
−	# * lang: language (default is sql)
+
−	# * host: server hostname or ip  (default is localhost)
+
−	# * port: server port (default is 50000)
+
−
+
−	def initialize(user = "monetdb", passwd = "monetdb", lang = "sql", host="127.0.0.1", port = "50000")
+
−		@user = user
+
−		@passwd = passwd
+
−		@lang = lang.downcase
+
−		@host = host
+
−		@port = port
+
−
+
−		@client_endianness = @@CLIENT_ENDIANNESS
+
−
+
−		@auth_iteration = 0
+
−		@connection_established = false
+
−
+
−		@transactions = MonetDBTransaction.new # handles a pool of transactions (generates and keeps track of savepoints)
+
−
+
−		if @@DEBUG == true
+
−			require 'logger'
+
−		end
+
−
+
−		if @lang[0, 3] == 'sql'
+
−			@lang = "sql"
+
−		end
+
−
+
−	end
+
−
+
−	# Connect to the database, creates a new socket
+
−	def connect(db_name = 'demo', auth_type = 'SHA1')
+
−		@database = db_name
+
−		@auth_type = auth_type
+
−
+
−		@socket = TCPSocket.new(@host, @port.to_i)
+
−		if real_connect
+
−			if @lang == MonetDBConnection::LANG_SQL
+
−				set_timezone
+
−				set_reply_size
+
−			end
+
−			true
+
−		end
+
−		false
+
−	end
+
−
+
−
+
−	# perform a real connection; retrieve challenge, proxy through merovinginan, build challenge and set the timezone
+
−	def real_connect
+
−
+
−		server_challenge = retrieve_server_challenge()
+
−		if server_challenge != nil
+
−			salt = server_challenge.split(':')[0]
+
−			@server_name = server_challenge.split(':')[1]
+
−			@protocol = server_challenge.split(':')[2].to_i
+
−			@supported_auth_types = server_challenge.split(':')[3].split(',')
+
−			@server_endianness = server_challenge.split(':')[4]
+
−			if @@SUPPORTED_PROTOCOLS.include?(@protocol) == false
+
−				raise MonetDBProtocolError, "Protocol not supported. The current implementation of ruby-monetdb works with MAPI protocols #{@@SUPPORTED_PROTOCOLS} only."
+
−			end
+
−			@pwhash = server_challenge.split(':')[5]
+
−		else
+
−			raise MonetDBConnectionError, "Error: server returned an empty challenge string."
+
−		end
+
−
+
−		# The server supports only RIPMED160 or crypt as an authentication hash function, but the driver does not.
+
−		if @supported_auth_types.length == 1
+
−			auth = @supported_auth_types[0]
+
−			if auth.upcase == "RIPEMD160"
+
−				raise MonetDBConnectionError, auth.upcase + " " + ": algorithm not supported by ruby-monetdb."
+
−			end
+
−		end
+
−
+
−		reply = build_auth_string_v9(@auth_type, salt, @database)
+
−
+
−		if @socket != nil
+
−			@connection_established = true
+
−
+
−			send(reply)
+
−			monetdb_auth = receive
+
−
+
−			if monetdb_auth.length == 0
+
−				# auth succeeded
+
−				true
+
−			else
+
−				if monetdb_auth[0].chr == MonetDBConnection::MSG_REDIRECT
+
−					#redirection
+
−
+
−					redirects = [] # store a list of possible redirects
+
−
+
−					monetdb_auth.split('\n').each do |m|
+
−						# strip the trailing ^mapi:
+
−						# if the redirect string start with something != "^mapi:" or is empty, the redirect is invalid and shall not be included.
+
−						if m[0..5] == "^mapi:"
+
−							redir = m[6..m.length]
+
−							# url parse redir
+
−							redirects.push(redir)
+
−						else
+
−							$stderr.print "Warning: Invalid Redirect #{m}"
+
−						end
+
−					end
+
−
+
−					if redirects.size == 0
+
−						raise MonetDBConnectionError, "No valid redirect received"
+
−					else
+
−						begin
+
−							uri = URI.split(redirects[0])
+
−							# Splits the string on following parts and returns array with result:
+
−							#
+
−							#  * Scheme
+
−							#  * Userinfo
+
−							#  * Host
+
−							#  * Port
+
−							#  * Registry
+
−							#  * Path
+
−							#  * Opaque
+
−							#  * Query
+
−							#  * Fragment
+
−							server_name = uri[0]
+
−							host   = uri[2]
+
−							port   = uri[3]
+
−							database   = uri[5].gsub(/^\//, '') if uri[5] != nil
+
−						rescue URI::InvalidURIError
+
−							raise MonetDBConnectionError, "Invalid redirect: #{redirects[0]}"
+
−						end
+
−					end
+
−
+
−					if server_name == MonetDBConnection::MONETDB_MEROVINGIAN
+
−						if @auth_iteration <= MonetDBConnection::MEROVINGIAN_MAX_ITERATIONS
+
−							@auth_iteration += 1
+
−							real_connect
+
−						else
+
−							raise MonetDBConnectionError, "Merovingian: too many iterations while proxying."
+
−						end
+
−					elsif server_name == MonetDBConnection::MONETDB_MSERVER
+
−						begin
+
−							@socket.close
+
−						rescue
+
−							raise MonetDBConnectionError, "I/O error while closing connection to #{@socket}"
+
−						end
+
−						# reinitialize a connection
+
−						@host = host
+
−						@port = port
+
−
+
−						connect(database, @auth_type)
+
−					else
+
−						@connection_established = false
+
−						raise MonetDBConnectionError, monetdb_auth
+
−					end
+
−				elsif monetdb_auth[0].chr == MonetDBConnection::MSG_INFO
+
−					raise MonetDBConnectionError, monetdb_auth
+
−				end
+
−			end
+
−		end
+
−	end
+
−
+
−	def savepoint
+
−		@transactions.savepoint
+
−	end
+
−
+
−	# Formats a <i>command</i> string so that it can be parsed by the server
+
−	def format_command(x)
+
−		return "X" + x + "\n"
+
−	end
+
−
+
−
+
−	# send an 'export' command to the server
+
−	def set_export(id, idx, offset)
+
−		send(format_command("export " + id.to_s + " " + idx.to_s + " " + offset.to_s ))
+
−	end
+
−
+
−	# send a 'reply_size' command to the server
+
−	def set_reply_size
+
−		send(format_command(("reply_size " + MonetDBConnection::REPLY_SIZE)))
+
−
+
−		response = receive
+
−
+
−		if response == MonetDBConnection::MSG_PROMPT
+
−			true
+
−		elsif response[0] == MonetDBConnection::MSG_INFO
+
−			raise MonetDBCommandError, "Unable to set reply_size: #{response}"
+
−		end
+
−
+
−	end
+
−
+
−	def set_output_seq
+
−		send(format_command("output seq"))
+
−	end
+
−
+
−	# Disconnect from server
+
−	def disconnect()
+
−		if  @connection_established
+
−			begin
+
−				@socket.close
+
−			rescue => e
+
−				$stderr.print e
+
−			end
+
−		else
+
−			raise MonetDBConnectionError, "No connection established."
+
−		end
+
−	end
+
−
+
−	# send data to a monetdb5 server instance and returns server's response
+
−	def send(data)
+
−		encode_message(data).each do |m|
+
−			@socket.write(m)
+
−		end
+
−	end
+
−
+
−	# receive data from a monetdb5 server instance
+
−	def receive
+
−		is_final, chunk_size = recv_decode_hdr
+
−
+
−		if chunk_size == 0
+
−			return ""  # needed on ruby-1.8.6 linux/64bit; recv(0) hangs on this configuration.
+
−		end
+
−
+
−		data = @socket.recv(chunk_size)
+
−
+
−		if is_final == false
+
−			while is_final == false
+
−				is_final, chunk_size = recv_decode_hdr
+
−				data +=  @socket.recv(chunk_size)
+
−			end
+
−		end
+
−
+
−		return data
+
−	end
+
−
+
−	#
+
−	# Builds and authentication string given the parameters submitted by the user (MAPI protocol v9).
+
−	#
+
−	def build_auth_string_v9(auth_type, salt, db_name)
+
−		if (auth_type.upcase == "MD5" or auth_type.upcase == "SHA1") and @supported_auth_types.include?(auth_type.upcase)
+
−			auth_type = auth_type.upcase
+
−			# Hash the password
+
−			pwhash = Hasher.new(@pwhash, @passwd)
+
−
+
−			digest = Hasher.new(auth_type, pwhash.hashsum + salt)
+
−			hashsum = digest.hashsum
+
−
+
−		elsif auth_type.downcase == "plain" # or not  @supported_auth_types.include?(auth_type.upcase)
+
−			# Keep it for compatibility with merovingian
+
−			auth_type = 'plain'
+
−			hashsum = @passwd + salt
+
−		elsif @supported_auth_types.include?(auth_type.upcase)
+
−			if auth_type.upcase == "RIPEMD160"
+
−				auth_type =  @supported_auth_types[@supported_auth_types.index(auth_type)+1]
+
−				$stderr.print "The selected hashing algorithm is not supported by the Ruby driver. #{auth_type} will be used instead."
+
−			end
+
−			# Hash the password
+
−			pwhash = Hasher.new(@pwhash, @passwd)
+
−
+
−			digest = Hasher.new(auth_type, pwhash.hashsum + salt)
+
−			hashsum = digest.hashsum
+
−		else
+
−			# The user selected an auth type not supported by the server.
+
−			raise MonetDBConnectionError, "#{auth_type} not supported by the server. Please choose one from #{@supported_auth_types}"
+
−		end
+
−		# Build the reply message with header
+
−		reply = @client_endianness + ":" + @user + ":{" + auth_type + "}" + hashsum + ":" + @lang + ":" + db_name + ":"
+
−	end
+
−
+
−	# builds a message to be sent to the server
+
−	def encode_message(msg = "")
+
−		message = Array.new
+
−		data = ""
+
−
+
−		hdr = 0 # package header
+
−		pos = 0
+
−		is_final = false # last package in the stream
+
−
+
−		while (! is_final)
+
−			data = msg[pos..pos+[@@MAX_MESSAGE_SIZE.to_i, (msg.length - pos).to_i].min]
+
−			pos += data.length
+
−
+
−			if (msg.length - pos) == 0
+
−				last_bit = 1
+
−				is_final = true
+
−			else
+
−				last_bit = 0
+
−			end
+
−
+
−			hdr = [(data.length << 1) | last_bit].pack('v')
+
−
+
−			message << hdr + data.to_s # Short Little Endian Encoding
+
−		end
+
−
+
−		message.freeze # freeze and return the encode message
+
−	end
+
−
+
−	# Used as the first step in the authentication phase; retrieves a challenge string from the server.
+
−	def retrieve_server_challenge()
+
−		server_challenge = receive
+
−	end
+
−
+
−	# reads and decodes the header of a server message
+
−	def recv_decode_hdr()
+
−		if @socket != nil
+
−			fb = @socket.recv(1)
+
−			sb = @socket.recv(1)
+
−
+
−			# Use exceptions handling to keep compatibility between different ruby
+
−			# versions.
+
−			#
+
−			# Chars are treated differently in ruby 1.8 and 1.9
+
−			# try do to ASCII to int conversion using ord (ruby 1.9)
+
−			# and if it fail fallback to character.to_i (ruby 1.8)
+
−			begin
+
−				fb = fb[0].ord
+
−				sb = sb[0].ord
+
−			rescue NoMethodError => one_eight
+
−				fb = fb[0].to_i
+
−				sb = sb[0].to_i
+
−			end
+
−
+
−			chunk_size = (sb << 7) | (fb >> 1)
+
−
+
−			is_final = false
+
−			if ( (fb & 1) == 1 )
+
−				is_final = true
+
−
+
−			end
+
−			# return the size of the chunk (in bytes)
+
−			return is_final, chunk_size
+
−		else
+
−			raise MonetDBSocketError, "Error while receiving data\n"
+
−		end
+
−	end
+
−
+
−	# Sets the time zone according to the Operating System settings
+
−	def set_timezone()
+
−		tz = Time.new
+
−		tz_offset = tz.gmt_offset / @@HOUR
+
−
+
−		# verify minute count!
+
−		if tz_offset <= -10
+
−			tz_offset = "'" + tz_offset.to_s + ":00'"
+
−		elsif tz_offset < 0
+
−			tz_offset = -tz_offset
+
−			tz_offset = "'-0" + tz_offset.to_s + ":00'"
+
−		elsif tz_offset <= 9
+
−			tz_offset = "'+0" + tz_offset.to_s + ":00'"
+
−		else
+
−			tz_offset = "'+" + tz_offset.to_s + ":00'"
+
−		end
+
−		query_tz = "sSET TIME ZONE INTERVAL " + tz_offset + " HOUR TO MINUTE;"
+
−
+
−		# Perform the query directly within the method
+
−		send(query_tz)
+
−		response = receive
+
−
+
−		if response == MonetDBConnection::MSG_PROMPT
+
−			true
+
−		elsif response[0].chr == MonetDBConnection::MSG_INFO
+
−			raise MonetDBQueryError, response
+
−		end
+
−	end
+
−
+
−	# Turns auto commit on/off
+
−	def set_auto_commit(flag=true)
+
−		if flag == false
+
−			ac = " 0"
+
−		else
+
−			ac = " 1"
+
−		end
+
−
+
−		send(format_command("auto_commit " + ac))
+
−
+
−		response = receive
+
−		if response == MonetDBConnection::MSG_PROMPT
+
−			@auto_commit = flag
+
−		elsif response[0].chr == MonetDBConnection::MSG_INFO
+
−			raise MonetDBCommandError, response
+
−			return
+
−		end
+
−
+
−	end
+
−
+
−	# Check the auto commit status (on/off)
+
−	def auto_commit?
+
−		@auto_commit
+
−	end
+
−
+
−	# Check if monetdb is running behind the merovingian proxy and forward the connection in case
+
−	def merovingian?
+
−		if @server_name.downcase == MonetDBConnection::MONETDB_MEROVINGIAN
+
−			true
+
−		else
+
−			false
+
−		end
+
−	end
+
−
+
−	def mserver?
+
−		if @server_name.downcase == MonetDBConnection::MONETDB_MSERVER
+
−			true
+
−		else
+
−			false
+
−		end
+
−	end
+
−end
+
−
+
−# handles transactions and savepoints. Can be used to simulate nested transactions.
+
−class MonetDBTransaction
+
−	SAVEPOINT_STRING = "monetdbsp"
+
−
+
−	def initialize
+
−		@id = 0
+
−		@savepoint = ""
+
−	end
+
−
+
−	def savepoint
+
−		@savepoint = SAVEPOINT_STRING + @id.to_s
+
−	end
+
−
+
−	def release
+
−		prev_id
+
−	end
+
−
+
−	def save
+
−		next_id
+
−	end
+
−
+
−	private
+
−	def next_id
+
−		@id += 1
+
−	end
+
−
+
−	def prev_id
+
−		@id -= 1
+
−	end
+
−
+
−end