Network.Haskoin.Block

This package provides block and block-related types.

Blocks

data Block

Data type describing a block in the bitcoin protocol. Blocks are sent in response to GetData messages that are requesting information from a block hash.

Constructors

Block

Fields

• blockHeader :: !BlockHeader

  Header information for this block.

• blockTxns :: ![Tx]

  List of transactions pertaining to this block.

Instances

Eq Block

Methods

(==) :: Block -> Block -> Bool

(/=) :: Block -> Block -> Bool

Read Block

Methods

readsPrec :: Int -> ReadS Block

readList :: ReadS [Block]

readPrec :: ReadPrec Block

readListPrec :: ReadPrec [Block]

Show Block

Methods

showsPrec :: Int -> Block -> ShowS

show :: Block -> String

showList :: [Block] -> ShowS

Serialize Block

Methods

put :: Putter Block

get :: Get Block

NFData Block

Methods

rnf :: Block -> ()

type BlockLocator = [BlockHash]

data GetBlocks

Data type representing a GetBlocks message request. It is used in the bitcoin protocol to retrieve blocks from a peer by providing it a BlockLocator object. The BlockLocator is a sparse list of block hashes from the caller node with the purpose of informing the receiving node about the state of the caller's blockchain. The receiver node will detect a wrong branch in the caller's main chain and send the caller appropriate Blocks. The response to a GetBlocks message is an Inv message containing the list of block hashes pertaining to the request.

Constructors

GetBlocks

Fields

• getBlocksVersion :: !Word32

  The protocol version

• getBlocksLocator :: !BlockLocator

  Block locator object. It is a list of block hashes from the most recent block back to the genesis block. The list is dense at first and sparse towards the end.

• getBlocksHashStop :: !BlockHash

  Hash of the last desired block. If set to zero, the maximum number of block hashes is returned (500).

Instances

Eq GetBlocks

Methods

(==) :: GetBlocks -> GetBlocks -> Bool

(/=) :: GetBlocks -> GetBlocks -> Bool

Read GetBlocks

Methods

readsPrec :: Int -> ReadS GetBlocks

readList :: ReadS [GetBlocks]

readPrec :: ReadPrec GetBlocks

readListPrec :: ReadPrec [GetBlocks]

Show GetBlocks

Methods

showsPrec :: Int -> GetBlocks -> ShowS

show :: GetBlocks -> String

showList :: [GetBlocks] -> ShowS

Serialize GetBlocks

Methods

put :: Putter GetBlocks

get :: Get GetBlocks

NFData GetBlocks

Methods

rnf :: GetBlocks -> ()

Block Headers

data BlockHeader

Data type recording information on a Block. The hash of a block is defined as the hash of this data structure. The block mining process involves finding a partial hash collision by varying the nonce in the BlockHeader and/or additional randomness in the coinbase tx of this Block. Variations in the coinbase tx will result in different merkle roots in the BlockHeader.

Instances

Eq BlockHeader

Methods

(==) :: BlockHeader -> BlockHeader -> Bool

(/=) :: BlockHeader -> BlockHeader -> Bool

Read BlockHeader

Methods

readsPrec :: Int -> ReadS BlockHeader

readList :: ReadS [BlockHeader]

readPrec :: ReadPrec BlockHeader

readListPrec :: ReadPrec [BlockHeader]

Show BlockHeader

Methods

showsPrec :: Int -> BlockHeader -> ShowS

show :: BlockHeader -> String

showList :: [BlockHeader] -> ShowS

Serialize BlockHeader

Methods

put :: Putter BlockHeader

get :: Get BlockHeader

NFData BlockHeader

Methods

rnf :: BlockHeader -> ()

createBlockHeader :: Word32 -> BlockHash -> Hash256 -> Word32 -> Word32 -> Word32 -> BlockHeader

blockVersion :: BlockHeader -> Word32

prevBlock :: BlockHeader -> BlockHash

merkleRoot :: BlockHeader -> Hash256

blockTimestamp :: BlockHeader -> Word32

blockBits :: BlockHeader -> Word32

bhNonce :: BlockHeader -> Word32

headerHash :: BlockHeader -> BlockHash

data GetHeaders

Similar to the GetBlocks message type but for retrieving block headers only. The response to a GetHeaders request is a Headers message containing a list of block headers pertaining to the request. A maximum of 2000 block headers can be returned. GetHeaders is used by thin (SPV) clients to exclude block contents when synchronizing the blockchain.

Constructors

GetHeaders

Fields

• getHeadersVersion :: !Word32

  The protocol version

• getHeadersBL :: !BlockLocator

  Block locator object. It is a list of block hashes from the most recent block back to the Genesis block. The list is dense at first and sparse towards the end.

• getHeadersHashStop :: !BlockHash

  Hash of the last desired block header. When set to zero, the maximum number of block headers is returned (2000)

Instances

Eq GetHeaders

Methods

(==) :: GetHeaders -> GetHeaders -> Bool

(/=) :: GetHeaders -> GetHeaders -> Bool

Read GetHeaders

Methods

readsPrec :: Int -> ReadS GetHeaders

readList :: ReadS [GetHeaders]

readPrec :: ReadPrec GetHeaders

readListPrec :: ReadPrec [GetHeaders]

Show GetHeaders

Methods

showsPrec :: Int -> GetHeaders -> ShowS

show :: GetHeaders -> String

showList :: [GetHeaders] -> ShowS

Serialize GetHeaders

Methods

put :: Putter GetHeaders

get :: Get GetHeaders

NFData GetHeaders

Methods

rnf :: GetHeaders -> ()

data Headers

The Headers type is used to return a list of block headers in response to a GetHeaders message.

Constructors

Headers

Fields

• headersList :: ![BlockHeaderCount]

  List of block headers with respective transaction counts

Instances

Eq Headers

Methods

(==) :: Headers -> Headers -> Bool

(/=) :: Headers -> Headers -> Bool

Read Headers

Methods

readsPrec :: Int -> ReadS Headers

readList :: ReadS [Headers]

readPrec :: ReadPrec Headers

readListPrec :: ReadPrec [Headers]

Show Headers

Methods

showsPrec :: Int -> Headers -> ShowS

show :: Headers -> String

showList :: [Headers] -> ShowS

Serialize Headers

Methods

put :: Putter Headers

get :: Get Headers

NFData Headers

Methods

rnf :: Headers -> ()

type BlockHeaderCount = (BlockHeader, VarInt)

BlockHeader type with a transaction count as VarInt

newtype BlockHash

Constructors

BlockHash

Fields

• getBlockHash :: Hash256

Instances

Eq BlockHash

Methods

(==) :: BlockHash -> BlockHash -> Bool

(/=) :: BlockHash -> BlockHash -> Bool

Ord BlockHash

Methods

compare :: BlockHash -> BlockHash -> Ordering

(<) :: BlockHash -> BlockHash -> Bool

(<=) :: BlockHash -> BlockHash -> Bool

(>) :: BlockHash -> BlockHash -> Bool

(>=) :: BlockHash -> BlockHash -> Bool

max :: BlockHash -> BlockHash -> BlockHash

min :: BlockHash -> BlockHash -> BlockHash

Read BlockHash

Methods

readsPrec :: Int -> ReadS BlockHash

readList :: ReadS [BlockHash]

readPrec :: ReadPrec BlockHash

readListPrec :: ReadPrec [BlockHash]

Show BlockHash

Methods

showsPrec :: Int -> BlockHash -> ShowS

show :: BlockHash -> String

showList :: [BlockHash] -> ShowS

IsString BlockHash

Methods

fromString :: String -> BlockHash

ToJSON BlockHash

Methods

toJSON :: BlockHash -> Value

toEncoding :: BlockHash -> Encoding

FromJSON BlockHash

Methods

parseJSON :: Value -> Parser BlockHash

Serialize BlockHash

Methods

put :: Putter BlockHash

get :: Get BlockHash

NFData BlockHash

Methods

rnf :: BlockHash -> ()

blockHashToHex :: BlockHash -> ByteString

hexToBlockHash :: ByteString -> Maybe BlockHash

Merkle Blocks

data MerkleBlock

Constructors

MerkleBlock

Fields

• merkleHeader :: !BlockHeader

  Header information for this merkle block.

• merkleTotalTxns :: !Word32

  Number of transactions in the block (including unmatched transactions).

• mHashes :: ![Hash256]

  Hashes in depth-first order. They are used to rebuild a partial merkle tree.

• mFlags :: ![Bool]

  Flag bits, packed per 8 in a byte. Least significant bit first. Flag bits are used to rebuild a partial merkle tree.

Instances

Eq MerkleBlock

Methods

(==) :: MerkleBlock -> MerkleBlock -> Bool

(/=) :: MerkleBlock -> MerkleBlock -> Bool

Read MerkleBlock

Methods

readsPrec :: Int -> ReadS MerkleBlock

readList :: ReadS [MerkleBlock]

readPrec :: ReadPrec MerkleBlock

readListPrec :: ReadPrec [MerkleBlock]

Show MerkleBlock

Methods

showsPrec :: Int -> MerkleBlock -> ShowS

show :: MerkleBlock -> String

showList :: [MerkleBlock] -> ShowS

Serialize MerkleBlock

Methods

put :: Putter MerkleBlock

get :: Get MerkleBlock

NFData MerkleBlock

Methods

rnf :: MerkleBlock -> ()

type MerkleRoot = Hash256

type FlagBits = [Bool]

type PartialMerkleTree = [Hash256]

calcTreeHeight

Arguments

:: Int

Number of transactions (leaf nodes).

-> Int

Height of the merkle tree.

Computes the height of a merkle tree.

calcTreeWidth

Arguments

:: Int

Number of transactions (leaf nodes).

-> Int

Height at which we want to compute the width.

-> Int

Width of the merkle tree.

Computes the width of a merkle tree at a specific height. The transactions are at height 0.

buildMerkleRoot

Arguments

:: [TxHash]

List of transaction hashes (leaf nodes).

-> MerkleRoot

Root of the merkle tree.

Computes the root of a merkle tree from a list of leaf node hashes.

calcHash

Arguments

:: Int

Height of the node in the merkle tree.

-> Int

Position of the node (0 for the leftmost node).

-> [TxHash]

Transaction hashes of the merkle tree (leaf nodes).

-> Hash256

Hash of the node at the specified position.

Computes the hash of a specific node in a merkle tree.

buildPartialMerkle

Arguments

:: [(TxHash, Bool)]

List of transactions hashes forming the leaves of the merkle tree and a bool indicating if that transaction should be included in the partial merkle tree.

-> (FlagBits, PartialMerkleTree)

Flag bits (used to parse the partial merkle tree) and the partial merkle tree.

Build a partial merkle tree.

extractMatches

Arguments

:: FlagBits

Flag bits (produced by buildPartialMerkle).

-> PartialMerkleTree

Partial merkle tree.

-> Int

Number of transaction at height 0 (leaf nodes).

-> Either String (MerkleRoot, [TxHash])

Merkle root and the list of matching transaction hashes.

Extracts the matching hashes from a partial merkle tree. This will return the list of transaction hashes that have been included (set to True) in a call to buildPartialMerkle.

Difficulty Target

decodeCompact :: Word32 -> Integer

Decode the compact number used in the difficulty target of a block into an Integer.

As described in the Satoshi reference implementation srcbignum.h:

The "compact" format is a representation of a whole number N using an unsigned 32bit number similar to a floating point format. The most significant 8 bits are the unsigned exponent of base 256. This exponent can be thought of as "number of bytes of N". The lower 23 bits are the mantissa. Bit number 24 (0x800000) represents the sign of N.

   N = (-1^sign) * mantissa * 256^(exponent-3)

encodeCompact :: Integer -> Word32

Encode an Integer to the compact number format used in the difficulty target of a block.