A 32-byte channel identifier.

Derived from the funding transaction by XORing funding_txid with funding_output_index (big-endian, altering the last 2 bytes).

For v2 channels, derived as SHA256(lesser-revocation-basepoint || greater-revocation-basepoint).

Construct a ChannelId from a 32-byte ByteString.

Returns Nothing if the input is not exactly 32 bytes.

>>> channelId (BS.replicate 32 0x00)
Just (ChannelId ...)
>>> channelId (BS.replicate 31 0x00)
Nothing

Extract the underlying ByteString from a ChannelId.

Amount in satoshis (1/100,000,000 of a bitcoin).

Stored as a Word64. Maximum valid value is 21,000,000 * 100,000,000 = 2,100,000,000,000,000 satoshis.

Amount in millisatoshis (1/1000 of a satoshi).

Stored as a Word64. Used for HTLC amounts and channel balances.

Convert Satoshis to MilliSatoshis.

>>> satoshisToMsat (Satoshis 1)
MilliSatoshis 1000

Convert MilliSatoshis to Satoshis, rounding down.

>>> msatToSatoshis (MilliSatoshis 1500)
Satoshis 1

A 64-byte compact ECDSA signature.

Used for commitment transaction signatures, HTLC signatures, and closing transaction signatures.

Construct a Signature from a 64-byte ByteString.

Returns Nothing if the input is not exactly 64 bytes.

Extract the underlying ByteString from a Signature.

A 33-byte compressed secp256k1 public key.

Used for funding pubkeys, basepoints, and per-commitment points.

Construct a Point from a 33-byte ByteString.

Returns Nothing if the input is not exactly 33 bytes.

Note: This only validates the length. Use secp256k1 libraries for full point validation.

Extract the underlying ByteString from a Point.

A 32-byte SHA256 payment hash.

Used to identify HTLCs. The preimage that hashes to this value is required to claim the HTLC.

Construct a PaymentHash from a 32-byte ByteString.

Returns Nothing if the input is not exactly 32 bytes.

Extract the underlying ByteString from a PaymentHash.

A 32-byte payment preimage.

The SHA256 hash of this value produces the corresponding PaymentHash. Knowledge of the preimage allows claiming an HTLC.

Construct a PaymentPreimage from a 32-byte ByteString.

Returns Nothing if the input is not exactly 32 bytes.

Extract the underlying ByteString from a PaymentPreimage.

A 32-byte per-commitment secret.

Used in revoke_and_ack and channel_reestablish messages to revoke old commitment transactions.

Construct a Secret from a 32-byte ByteString.

Returns Nothing if the input is not exactly 32 bytes.

Extract the underlying ByteString from a Secret.

A 32-byte transaction identifier.

The double-SHA256 hash of a serialized transaction.

Construct a TxId from a 32-byte ByteString.

Returns Nothing if the input is not exactly 32 bytes.

Extract the underlying ByteString from a TxId.

A transaction outpoint (txid + output index).

Identifies a specific output of a transaction.

A script pubkey (output script).

Variable length; used in shutdown messages, closing transactions, etc.

Construct a ScriptPubKey from a ByteString.

Accepts any length; validation of script structure is left to higher layers.

Extract the underlying ByteString from a ScriptPubKey.

A 32-byte chain hash.

Identifies the blockchain (typically the genesis block hash). Used in open_channel to specify which chain the channel will reside on.

Construct a ChainHash from a 32-byte ByteString.

Returns Nothing if the input is not exactly 32 bytes.

Extract the underlying ByteString from a ChainHash.

A short channel identifier (8 bytes).

Encodes the block height (3 bytes), transaction index (3 bytes), and output index (2 bytes) of the funding transaction output.

This is a compact representation for referencing channels in gossip and routing.

Construct a ShortChannelId from block height, tx index, and output index.

Returns Nothing if any component exceeds its maximum value:

• block height: max 16,777,215 (2^24 - 1)
• tx index: max 16,777,215 (2^24 - 1)
• output index: max 65,535 (2^16 - 1)

>>> shortChannelId 800000 1234 0
Just (ShortChannelId ...)

Extract the block height from a ShortChannelId.

Extract the transaction index from a ShortChannelId.

Extract the output index from a ShortChannelId.

Feature bits (variable length).

Encodes supported/required features. Even bits indicate required features; odd bits indicate optional features.

Construct FeatureBits from a ByteString.

Accepts any length; feature bit parsing is left to higher layers.

Extract the underlying ByteString from FeatureBits.

A 1366-byte onion routing packet.

Contains encrypted routing information for HTLC forwarding, as specified in BOLT #4.

Construct an OnionPacket from a 1366-byte ByteString.

Returns Nothing if the input is not exactly 1366 bytes.

Extract the underlying ByteString from an OnionPacket.

Length of a channel_id in bytes (32).

Length of a signature in bytes (64, compact format).

Length of a compressed secp256k1 public key in bytes (33).

Length of a transaction ID in bytes (32).

Length of a chain hash in bytes (32).

Length of a short_channel_id in bytes (8).

Length of a payment hash in bytes (32).

Length of a payment preimage in bytes (32).

Length of an onion routing packet in bytes (1366).

Length of a per-commitment secret in bytes (32).