Network.Haskoin.Block.Merkle

Documentation

data MerkleBlock

Filtered block: a block with a partial Merkle tree that only includes the transactions that pass a bloom filter that was negotiated.

Constructors

MerkleBlock

Fields

• merkleHeader :: !BlockHeader

  block header

• merkleTotalTxns :: !Word32

  total number of transactions in block

• mHashes :: !PartialMerkleTree

  hashes in depth-first order

• mFlags :: !FlagBits

  bits to rebuild partial merkle tree

Instances

Eq MerkleBlock

Defined in Network.Haskoin.Block.Merkle

Methods

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

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

Show MerkleBlock

Defined in Network.Haskoin.Block.Merkle

Methods

showsPrec :: Int -> MerkleBlock -> ShowS

show :: MerkleBlock -> String

showList :: [MerkleBlock] -> ShowS

Serialize MerkleBlock

Defined in Network.Haskoin.Block.Merkle

Methods

put :: Putter MerkleBlock

get :: Get MerkleBlock

NFData MerkleBlock

Defined in Network.Haskoin.Block.Merkle

Methods

rnf :: MerkleBlock -> ()

type MerkleRoot = Hash256

Hash of the block's Merkle root.

type FlagBits = [Bool]

Bits that are used to rebuild partial merkle tree transaction hash list.

type PartialMerkleTree = [Hash256]

Partial Merkle tree for a filtered block.

buildMerkleRoot

Arguments

:: [TxHash]

transaction hashes (leaf nodes)

-> MerkleRoot

root of the Merkle tree

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

merkleBlockTxs :: Network -> MerkleBlock -> Either String [TxHash]

Get matching transactions from Merkle block.

testMerkleRoot :: Network -> MerkleBlock -> Bool

Check if Merkle block root is valid against the block header.

Helper functions

buildPartialMerkle

Arguments

:: [(TxHash, Bool)]

transaction hash and whether to include

-> (FlagBits, PartialMerkleTree)

flag bits and partial Merkle tree

Build a partial Merkle tree. Provide a list of tuples with all transaction hashes in the block, and whether the transaction is to be included in the partial tree. Returns a flag bits structure and the computed partial Merkle tree.

decodeMerkleFlags :: [Word8] -> FlagBits

Unpack Merkle flags into FlagBits structure.

encodeMerkleFlags :: FlagBits -> [Word8]

Pack Merkle flags from FlagBits.

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.

hash2 :: Hash256 -> Hash256 -> Hash256

Concatenate and compute double SHA256.

calcHash

Arguments

:: Int

height of the node

-> Int

position of the node (0 for the leftmost node)

-> [TxHash]

transaction hashes (leaf nodes)

-> Hash256

hash of the node at the specified position

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

traverseAndBuild :: Int -> Int -> [(TxHash, Bool)] -> (FlagBits, PartialMerkleTree)

Helper function to build partial Merkle tree. Used by buildPartialMerkle above.

traverseAndExtract :: Int -> Int -> Int -> FlagBits -> PartialMerkleTree -> Maybe (MerkleRoot, [TxHash], Int, Int)

Helper function to extract transaction hashes from partial Merkle tree.

extractMatches

Arguments

:: Network

-> FlagBits

-> PartialMerkleTree

-> Int

number of transaction at height 0 (leaf nodes)

-> Either String (MerkleRoot, [TxHash])

Merkle root and 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.

splitIn :: Int -> [a] -> [[a]]

Helper function to split a list in chunks Int length. Last chunk may be smaller.

boolsToWord8 :: [Bool] -> Word8

Pack up to eight bools in a byte.