Massive-ish in-place commit.

Start of database, wire protocol specification

lib/em-bitcoin.rb

@@ -1,13 +1,399 @@
 require 'eventmachine'
 
-module EventMachine
-  module Protocols
-    # Implements the TCP protocol that Bitcoin peers speak to each other. This
-    # class can be used for both incoming and outgoing connections
+
+# TODO: Break this out into its own little library, since it's general-purpose.
+require 'bindata'
+# Implementation of the BitCoin wire protocol, written using bindata.
+# Reference: https://en.bitcoin.it/wiki/Protocol_specification
+# 
+# @author Nick Thomas <nick@lupine.me.uk
+module BtcWireProto
+  CURRENT_VERSION = 32100
+  # Comprehensive list of known networks. The hex values are what you see in
+  # MessageHdr#magic and the symbols are their known friendly names.
+  NETWORKS = {
+    :main      => 0xF9BEB4D9,
+    0xF9BEB4D9 => :main,
+
+    :testnet   => 0xFABFB5DA,
+    0xFABFB5DA => :testnet
+  }
+  
+  # Comprehensive list of known inventory vector types.
+  INV_VEC_TYPES = {
+    0 => :error,
+    :error => 0,
+    
+    1 => :msg_tx,
+    :msg_tx => 1,
+    
+    2 => :msg_block,
+    :msg_block => 2
+  }
+  
+  ## Components of payloads ##
+  
+  # Bitmask advertising various capabilities of the node.
   # @author Nick Thomas <nick@lupine.me.uk>  
-    class BitcoinPeer < EventMachine::Connection
-      # TODO!
-      def receive_data(data)
+  class ServicesMask < BinData::Record
+    endian :little
+    
+    bit62 :undefined
+    bit1  :node_network
+    bit1  :undefined
+  end
+
+  # Structure holding an IP address and port in a slightly unusual format.
+  # This one is big-endian - everything else is little-endian.
+  #
+  # @author Nick Thomas <nick@lupine.me.uk>
+  class NetAddr < BinData::Record
+    endian :big
+    services_mask :services
+    uint128 :ip # IPv6 address. IPv4 addresses given as IPv6-mapped IPv4
+    uint16 :port
+  end
+  
+  # Like a NetAddr but with a timestamp to boot.
+  # @author Nick Thomas <nick@lupine.me.uk>
+  def TimestampedNetAddr < BinData::Record
+    uint32 :timestamp, :endian => :little
+    net_addr :net_addr
+  end
+  
+  # Variable-length integer. This is slightly scary.
+  # @author Nick Thomas <nick@lupine.me.uk>
+  class VarInt < BinData::BasePrimitive
+    def value_to_binary_string(val)
+      val = val.to_i
+
+      case val
+      if val < -0xffffffffffffffff # unrepresentable
+        ""
+      elsif val < 0  # 64-bit negative integer
+        top_32 = (val & 0xffffffff00000000) >> 32
+        btm_32 = val & 0x00000000ffffffff
+        [0xff, top_32, btm_32].pack("CVV") 
+      elsif val <= 0xfc # 8-bit (almost) positive integer
+        [val].pack("C")
+      elsif val <= 0xffff # 16-bit positive integer
+        [0xfd, val].pack("Cv")
+      elsif val <= 0xffffffff # 32-bit positive integer
+        [0xfe, val].pack("CV")
+      else  # We can't represent this, whatever it is
+        ""
+      end 
+    end
+    
+    def read_and_return_value(io)
+      return nil if str.size < 1
+      magic = read_uint8(io)
+        if magic <= 0xfc # 8-bit (almost) positive integer
+          magic
+        elsif magic == 0xfd # 16-bit positive integer
+          read_uint16(io)
+        elsif magic == 0xfe # 32-bit positive integer
+          read_uint32(io)
+        elsif magic == 0xff # 64-bit negative integer  
+          -(read_uint64(io)
+        end
+      end
+    end
+    
+    def sensible_default
+      0
+    end
+  end
+
+  # Variable-length pascal string with a variable-length int specifying the
+  # length. I kid you not.
+  # @author Nick Thomas <nick@lupine.me.uk>
+  class VarStr < BinData::Primitive
+    endian :little
+
+    var_int :len, :value => lambda { data.length }
+    string  :data, :read_length => :len
+    
+    def get    ; self.data     ; end
+    def set(v) ; self.data = v ; end
+  end
+  
+  class InventoryVector < BinData::Record
+    endian :little
+
+    uint32 :type # For values, see INV_VEC_TYPES
+    string :hash, :length => 32
+  end
+  
+  # Simple class wrapping raw SHA256 data. Might have utility methods later.
+  # @author Nick Thomas <nick@lupine.me.uk>
+  class Sha256 < BinData::Record
+    uint256 :data # Raw SHA256 data
+  end
+  SHA256 = Sha256
+
+  class TransactionIn < BinData::Record
+    struct :previous_output do
+      sha256 :hash
+      uint32 :index
+    end
+    var_str :signature_script # Script for confirming transaction authorisation
+    uint32 :sequence # Version of this record. 
+  end
+  
+  class TranactionOut < BinData::Record
+    uint64 :value
+    var_str :pk_script # Script containing conditions to claim to transaction
+  end
+
+
+  ## Payloads ##
+
+  # Payload for a version message
+  # @author Nick Thomas <nick@lupine.me.uk>
+  class Version < BinData::Record
+    endian :little
+
+    uint32        :version
+    services_mask :services
+    uint64        :timestamp
+    net_addr      :addr_me
+    net_addr      :addr_you,     :only_if => lambda { version >= 106 }
+    uint64        :nonce,        :only_if => lambda { version >= 106 }
+    var_str       :sub_version,  :only_if => lambda { version >= 106 }
+    uint32        :start_height, :only_if => lambda { version >= 209 }
+  end
+  
+  # Payload for an addr message in versions earlier than 31402. These are
+  # used to get a list of peers to interact with.
+  # @author Nick Thomas <nick@lupine.me.uk>
+  class AddrPre31402 < BinData::Record
+    endian :little
+    
+    var_int :count
+    array :addrs, :type => :net_addr,
+      :read_until => lambda { index == count - 1 }
+
+  end
+  
+  # Payload for an addr message in versions later than 31402. A timestamp was
+  # added to the list of addresses, but otherwise it's the same as AddrPre31402
+  # @author Nick Thomas <nick@lupine.me.uk>
+  class AddrFrom31402 < BinData::Record
+    endian :little
+    
+    var_int :count
+    array :timestamped_addrs, :type => :timestamped_net_addr,
+      :read_until => lambda { index == count - 1 }
+  end
+  
+  # Payload for a getdata or inv message. This lets the peer advertise the
+  # various objects it has knowledge of.
+  # @author Nick Thomas <nick@lupine.me.uk>  
+  class Inventory < BinData::Record
+    endian :little
+
+    var_int :count
+    array :items, :type => :inventory_vector,
+      :read_until => lambda { index == count - 1 }
+  end
+  
+  # Payload for a getblocks or getheaders message. Specifies a set of blocks
+  # that the sender wants details of.
+  # @author Nick thomas <nick@lupine.me.uk>
+  class BlockSet < BinData::Record
+    endian :little
+    
+    uint32  :version
+    var_int :start_count
+    array   :hash_start, :type => :sha256,
+            :read_until => lambda { index == start_count - 1 }    
+    # Hash of the last desired block, or 0 to get as many as possible (max: 500)
+    sha256  :hash_stop, :length => 32
+  end
+  
+  class Transaction < BinData::Record
+    endian :little
+    
+    uint32  :version
+    var_int :tx_in_count
+    array   :transactions_in, :type => :transaction_in,
+            :read_until => lambda { index == tx_in_count - 1 }
+    var_int :tx_out_count
+    array   :transactions_out, :type => :transaction_out,
+            :read_until => lambda { index == tx_in_count - 1 }
+    uint32  :lock_time
+  end
+
+  ## Top-level message format ##
+  
+  class MessageHdr < BinData::Record
+    endian :little
+    uint32 :magic
+    string :command, :length => 12
+    uint32 :payload_len
+    uint32 :checksum, :onlyif => :has_checksum?
+    
+    protected
+    
+    # version and verack messages don't have a checksum. The rest do.
+    # @return[Boolean] does this message header have a checksum field or not?
+    def has_checksum?
+      command != "version" && command != "verack"
+    end 
+  end
+
+  # Everything on the wire is a Message.
+  class Message < BinData::Record
+  
+    # @param[Fixnum,nil] version The protocol version. Setting this affects
+    # the layout of various fields.
+    def initialize(version = nil)
+      @version = version || BtcWireProto::CURRENT_VERSION
+    end
+
+    message_hdr :header
+    
+    choice :payload, :selection => :payload_choice do
+      version         "version"
+      addr_pre_31402  "addr_pre_31402"
+      addr_from_31402 "addr_from_31402"
+      inventory       "inv"
+      inventory       "getdata"
+      block_set       "getblocks"
+      block_set       "getheaders"
+      transaction     "tx"
+    end
+
+    protected
+
+    def payload_choice
+      return header.command if %w{
+        version inv getdata getblocks getheaders tx
+      }.include?(header.command)
+
+      case header.command
+      when "verack"  then nil # No payload for a verack message
+      when "addr" # two forms, depending on protocol version
+        @version < 31402 ? "addr_pre_31402" : "addr_from_31402"
+      else
+        nil
+      end
+    end
+  end
+end
+
+
+module EventMachine
+  module Protocols
+    # Implements the TCP protocol that Bitcoin peers speak to each other. This
+    # module is mixed into both incoming and outgoing connections.
+    #
+    # We implement the protocol as a simple(ish!) state machine. When we want
+    # something doing, we call state(sym, data) to append that to the 
+    # list of things to do. If something is urgent, we can call state! to
+    # put it at the beginning of the list.
+    #
+    # Here is a list of states: 
+    #  send_ver, recv_ver, verify_ver
+    #  send_verack, recv_verack
+    #  wait
+    #
+    # We must receive a configuration object before we can do much of interest -
+    # this is received
+    #
+    # @author Nick Thomas <nick@lupine.me.uk>
+    module BitcoinPeer
+      
+      protected
+      
+      # Sets up the variables required to manage the state machine. Should be
+      # called before you try to push a state - in post_init, say.
+      def init_state!
+        @state_m = Mutex.new # Synchronize around @states and @working
+        @state_m.synchronize do
+          @states = []
+          @working = false
+        end
+      end
+      
+      # Checks the current configuration object to see if we have a valid config
+      # or not.
+      # @return[Array[true|false, msg]] Whether the config is valid, and an
+      #   optional message specifying why it's invalid, if it is.
+      def valid_config?
+        [false, "configuration check not implemented yet"]
+      end
+      
+      # Push a state to the end of the state queue.       
+      def state(new_state, data = nil)
+        @state_m.synchronize { @states.push(new_state, data) }
+      end
+      
+      # Add a state to the start of the state queue.
+      def state!(new_state, data = nil)
+        @state_m.synchronize { @states.unshift(new_state, data) }
+      end
+      
+      # State machine behaviours now. 
+      
+      # Send a 'version' message to the peer.
+      # Next 
+      def send_ver
+
+      end
+      
+    end
+    
+    # EventMachine protocol class that handles an *outgoing* connection to
+    # another bitcoin peer. Common functionality (p2p!) is held in BitcoinPeer.
+    #
+    # State machine flow: 
+    #   send_ver, recv_verack
+    #   recv_ver, verify_ver, send_verack
+    # 
+    # @author Nick Thomas <nick@lupine.me.uk>
+    class BitcoinClient < EM::Connection
+    include BitcoinPeer
+
+      # @param[Object] config See the BitcoinPeer#valid_config?
+      def initialize(config)
+        super
+        @config = config
+        result, msg = valid_config?
+        raise ArgumentError.new("Invalid configuration: #{msg}") unless result
+        
+        init_state!
+      end
+
+      def post_init
+        state(:send_ver)
+      end
+    end
+    
+    # EventMachine protocol class that handles an *incoming* connection from
+    # another bitcoin peer. Common functionality (p2p!) is held in BitcoinPeer
+    #
+    # State machine flow:
+    #   recv_ver, verify_ver, send_verack
+    #   send_ver, recv_verack
+    #
+    # @author Nick Thomas <nick@lupine.me.uk>
+    class BitcoinServer < EM::Connection
+      include BitcoinPeer
+
+      # @param[Object] config See the BitcoinPeer#valid_config?
+      def initialize(config)
+        super
+        @config = config
+        result, msg = valid_config?
+        raise ArgumentError.new("Invalid configuration: #{msg}") unless result
+        
+        init_state!
+      end
+
+      def post_init
+        state(:recv_ver)
       end
     end
   end

lib/sharp-coin/config.rb

@@ -45,6 +45,14 @@ module SharpCoin
         [telnet_host, telnet_port]
       end
       
+      def db_settings
+        { :adapter => 'sqlite', :database => 'sharp-coin.sqlite' }
+      end
+      
+      def db_automigrate?
+        true
+      end
+    
     end
     
   end

lib/sharp-coin/db.rb

@@ -1,11 +1,27 @@
-gem 'activerecord', '3.0.7' # FIXME: Ugh
-
-require 'active_record'
+begin 
+  require 'active_record'
+rescue LoadError => err
+  gem 'activerecord', '3.0.7' # FIXME: Ugh. Ruby doesn't find it without this..
+  retry
+end
 
 module SharpCoin
   module DB
+    include Logging
+
     class << self
       def setup!
+        ActiveRecord::Base.logger = logger
+        ActiveRecord::Base.include_root_in_json = false
+        
+        ActiveRecord::Base.establish_connection(Config::db_settings)
+
+         if Config::db_automigrate?
+           log(:info, "Performing automigration")
+           ActiveRecord::Migration.verbose = false
+           ActiveRecord::Migrator.migrate(File.join(File.dirname(__FILE__), 'db', 'migrations'))
+         end
+tup!
 
       end
 

lib/sharp-coin/db/key.rb

@@ -0,0 +1,12 @@
+module SharpCoin
+  module DB
+
+    # Base class for the various kinds of key we use in SharpCoin. They all
+    # need storing here.  
+    # @author Nick Thomas <nick@lupine.me.uk>
+    class Key < ActiveRecord::Base
+      has_and_belongs_to_many :wallets
+    end
+
+  end
+end

lib/sharp-coin/db/migrations/20110515171912_initial_schema.rb

@@ -0,0 +1,38 @@
+class InitialSchema < ActiveRecord::Migration
+
+  def self.up
+    create_table :blocks do |t|
+      t.binary :raw_data # Wire-format data for the block. Not much point
+                         # decomposing it just to recompose it later.
+    end
+
+    create_table :keys do |t|
+      t.string :major_type, :null => false # "RSA", "DSA", "EC", etc
+      t.string :minor_type, :null => false # "2048", "1024", secp256k1", etc.
+      t.binary :der_data,   :null => false # DER-format binary data for the key
+    end
+
+    create_table :users do |t|
+      t.string :name,     :null => false
+      t.string :email,    :null => false
+      t.string :password, :null => false
+      # user has_many wallets (but one by default)
+    end
+    
+    create_table :wallets do |t|
+      t.string :name, :default => "default", :null => false
+      t.references :user, :null => false # wallet has_one user
+    end
+    
+    # Join tables
+    create_table :keys_wallets, :id => false do |t|
+      t.references :key
+      t.references :wallet
+    end
+    
+  end
+  
+  def self.down
+  end
+  
+end

lib/sharp-coin/db/user.rb

@@ -0,0 +1,24 @@
+module SharpCoin
+  module DB
+
+    # An individual who has an account on the server. 
+    # @author Nick Thomas <nick@lupine.me.uk>
+    class User
+      validates_presence_of :email
+      validates_presence_of :name
+      validates_presence_of :password
+
+      # Should always have at least one wallet. These have a list of keys, which
+      # are addresses that  money can be sent to / from.
+      # As long as we have the keys, we can (in theory) construct a complete
+      # transaction history for the user.
+      has_many :wallets, :dependent => :destroy
+      
+      before_create do
+        build_wallet if wallets.empty?
+      end
+
+    end
+
+  end
+end

lib/sharp-coin/db/wallet.rb

@@ -0,0 +1,18 @@
+module SharpCoin
+  module DB
+
+    # An individual who has an account on the server. 
+    # @author Nick Thomas <nick@lupine.me.uk>
+    class Wallet
+
+      belongs_to :user, :required => true
+
+      # These are the keys against which transactions are made. By collecting
+      # all transactions for all keys in this wallet, we can come up with a
+      # complete history (and so, current balance) for this wallet
+      has_and_belongs_to_many :keys
+
+    end
+
+  end
+end

lib/sharp-coin/server.rb

@@ -21,8 +21,21 @@ module SharpCoin
     # EM::run { ... } block
     def run
       @running = true
-      @thin = Thin::Server.start(Interface::Web, *(Config::http_bind))
-      @telnet = EM::start_server(*([Config::telnet_bind, Interface::Telnet].flatten))
+
+      @http_server = Thin::Server.start(Interface::Web, *(Config::http_bind))
+
+      @telnet_server = EM::start_server(
+        Config::telnet_host,
+        Config::telnet_port,
+        Interface::Telnet
+      )
+
+      @bitcoin_server = EM::start_server(
+        Config::bitcoin_server_host,
+        Config::bitcoin_server_port,
+        EM::P::BitcoinServer,
+        Config
+      )  
     end
 
     # @return[Boolean] Is this server instance currently running?
@@ -32,8 +45,9 @@ module SharpCoin
     
     # Stop the various services.
     def stop
-      @thin.stop
-      @telnet.stop
+      @bitcoin_server.stop
+      @http_server.stop
+      @telnet_server.stop
       @running = false
     end