X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fonion_message%2Fpacket.rs;h=2fb2407dbdd093bdbe4ae260e31f12fbe4722d8a;hb=0ecb4b093ac1134cbf06275cc48dd79ef7524774;hp=1337bdb14d5d6c3bf83fcadc5beebcea8b6d70d8;hpb=e45db2bf6c900fe70d679a75f450456c7a5b09cc;p=rust-lightning diff --git a/lightning/src/onion_message/packet.rs b/lightning/src/onion_message/packet.rs index 1337bdb1..2fb2407d 100644 --- a/lightning/src/onion_message/packet.rs +++ b/lightning/src/onion_message/packet.rs @@ -12,22 +12,23 @@ use bitcoin::secp256k1::PublicKey; use bitcoin::secp256k1::ecdh::SharedSecret; -use ln::msgs::DecodeError; -use ln::onion_utils; -use super::blinded_route::{BlindedRoute, ForwardTlvs, ReceiveTlvs}; -use util::chacha20poly1305rfc::{ChaChaPolyReadAdapter, ChaChaPolyWriteAdapter}; -use util::ser::{BigSize, FixedLengthReader, LengthRead, LengthReadable, LengthReadableArgs, Readable, ReadableArgs, Writeable, Writer}; +use crate::blinded_path::{BlindedPath, ForwardTlvs, ReceiveTlvs}; +use crate::ln::msgs::DecodeError; +use crate::ln::onion_utils; +use super::messenger::CustomOnionMessageHandler; +use crate::util::chacha20poly1305rfc::{ChaChaPolyReadAdapter, ChaChaPolyWriteAdapter}; +use crate::util::ser::{BigSize, FixedLengthReader, LengthRead, LengthReadable, LengthReadableArgs, Readable, ReadableArgs, Writeable, Writer}; use core::cmp; -use io::{self, Read}; -use prelude::*; +use crate::io::{self, Read}; +use crate::prelude::*; // Per the spec, an onion message packet's `hop_data` field length should be // SMALL_PACKET_HOP_DATA_LEN if it fits, else BIG_PACKET_HOP_DATA_LEN if it fits. pub(super) const SMALL_PACKET_HOP_DATA_LEN: usize = 1300; pub(super) const BIG_PACKET_HOP_DATA_LEN: usize = 32768; -#[derive(Clone, Debug, PartialEq)] +#[derive(Clone, Debug, PartialEq, Eq)] pub(crate) struct Packet { pub(super) version: u8, pub(super) public_key: PublicKey, @@ -92,34 +93,63 @@ impl LengthReadable for Packet { /// Onion message payloads contain "control" TLVs and "data" TLVs. Control TLVs are used to route /// the onion message from hop to hop and for path verification, whereas data TLVs contain the onion /// message content itself, such as an invoice request. -pub(super) enum Payload { +pub(super) enum Payload { /// This payload is for an intermediate hop. Forward(ForwardControlTlvs), /// This payload is for the final hop. Receive { control_tlvs: ReceiveControlTlvs, - reply_path: Option, - // Coming soon: - // message: Message, + reply_path: Option, + message: OnionMessageContents, } } -// Coming soon: -// enum Message { -// InvoiceRequest(InvoiceRequest), -// Invoice(Invoice), -// InvoiceError(InvoiceError), -// CustomMessage, -// } +#[derive(Debug)] +/// The contents of an onion message. In the context of offers, this would be the invoice, invoice +/// request, or invoice error. +pub enum OnionMessageContents { + // Coming soon: + // Invoice, + // InvoiceRequest, + // InvoiceError, + /// A custom onion message specified by the user. + Custom(T), +} + +impl OnionMessageContents { + /// Returns the type that was used to decode the message payload. + /// + /// This is not exported to bindings users as methods on non-cloneable enums are not currently exportable + pub fn tlv_type(&self) -> u64 { + match self { + &OnionMessageContents::Custom(ref msg) => msg.tlv_type(), + } + } +} + +/// This is not exported to bindings users as methods on non-cloneable enums are not currently exportable +impl Writeable for OnionMessageContents { + fn write(&self, w: &mut W) -> Result<(), io::Error> { + match self { + OnionMessageContents::Custom(msg) => Ok(msg.write(w)?), + } + } +} + +/// The contents of a custom onion message. +pub trait CustomOnionMessageContents: Writeable { + /// Returns the TLV type identifying the message contents. MUST be >= 64. + fn tlv_type(&self) -> u64; +} /// Forward control TLVs in their blinded and unblinded form. pub(super) enum ForwardControlTlvs { - /// If we're sending to a blinded route, the node that constructed the blinded route has provided + /// If we're sending to a blinded path, the node that constructed the blinded path has provided /// this hop's control TLVs, already encrypted into bytes. Blinded(Vec), /// If we're constructing an onion message hop through an intermediate unblinded node, we'll need /// to construct the intermediate hop's control TLVs in their unblinded state to avoid encoding - /// them into an intermediate Vec. See [`super::blinded_route::ForwardTlvs`] for more info. + /// them into an intermediate Vec. See [`crate::blinded_path::ForwardTlvs`] for more info. Unblinded(ForwardTlvs), } @@ -127,40 +157,42 @@ pub(super) enum ForwardControlTlvs { pub(super) enum ReceiveControlTlvs { /// See [`ForwardControlTlvs::Blinded`]. Blinded(Vec), - /// See [`ForwardControlTlvs::Unblinded`] and [`super::blinded_route::ReceiveTlvs`]. + /// See [`ForwardControlTlvs::Unblinded`] and [`crate::blinded_path::ReceiveTlvs`]. Unblinded(ReceiveTlvs), } // Uses the provided secret to simultaneously encode and encrypt the unblinded control TLVs. -impl Writeable for (Payload, [u8; 32]) { +impl Writeable for (Payload, [u8; 32]) { fn write(&self, w: &mut W) -> Result<(), io::Error> { match &self.0 { Payload::Forward(ForwardControlTlvs::Blinded(encrypted_bytes)) => { - encode_varint_length_prefixed_tlv!(w, { - (4, encrypted_bytes, vec_type) + _encode_varint_length_prefixed_tlv!(w, { + (4, *encrypted_bytes, vec_type) }) }, Payload::Receive { - control_tlvs: ReceiveControlTlvs::Blinded(encrypted_bytes), reply_path + control_tlvs: ReceiveControlTlvs::Blinded(encrypted_bytes), reply_path, message, } => { - encode_varint_length_prefixed_tlv!(w, { + _encode_varint_length_prefixed_tlv!(w, { (2, reply_path, option), - (4, encrypted_bytes, vec_type) + (4, *encrypted_bytes, vec_type), + (message.tlv_type(), message, required) }) }, Payload::Forward(ForwardControlTlvs::Unblinded(control_tlvs)) => { let write_adapter = ChaChaPolyWriteAdapter::new(self.1, &control_tlvs); - encode_varint_length_prefixed_tlv!(w, { + _encode_varint_length_prefixed_tlv!(w, { (4, write_adapter, required) }) }, Payload::Receive { - control_tlvs: ReceiveControlTlvs::Unblinded(control_tlvs), reply_path, + control_tlvs: ReceiveControlTlvs::Unblinded(control_tlvs), reply_path, message, } => { let write_adapter = ChaChaPolyWriteAdapter::new(self.1, &control_tlvs); - encode_varint_length_prefixed_tlv!(w, { + _encode_varint_length_prefixed_tlv!(w, { (2, reply_path, option), - (4, write_adapter, required) + (4, write_adapter, required), + (message.tlv_type(), message, required) }) }, } @@ -168,28 +200,54 @@ impl Writeable for (Payload, [u8; 32]) { } } -// Uses the provided secret to simultaneously decode and decrypt the control TLVs. -impl ReadableArgs for Payload { - fn read(r: &mut R, encrypted_tlvs_ss: SharedSecret) -> Result { +// Uses the provided secret to simultaneously decode and decrypt the control TLVs and data TLV. +impl ReadableArgs<(SharedSecret, &H)> for Payload<::CustomMessage> { + fn read(r: &mut R, args: (SharedSecret, &H)) -> Result { + let (encrypted_tlvs_ss, handler) = args; + let v: BigSize = Readable::read(r)?; let mut rd = FixedLengthReader::new(r, v.0); - let mut reply_path: Option = None; + let mut reply_path: Option = None; let mut read_adapter: Option> = None; let rho = onion_utils::gen_rho_from_shared_secret(&encrypted_tlvs_ss.secret_bytes()); - decode_tlv_stream!(&mut rd, { + let mut message_type: Option = None; + let mut message = None; + decode_tlv_stream_with_custom_tlv_decode!(&mut rd, { (2, reply_path, option), - (4, read_adapter, (option: LengthReadableArgs, rho)) + (4, read_adapter, (option: LengthReadableArgs, rho)), + }, |msg_type, msg_reader| { + if msg_type < 64 { return Ok(false) } + // Don't allow reading more than one data TLV from an onion message. + if message_type.is_some() { return Err(DecodeError::InvalidValue) } + + message_type = Some(msg_type); + match handler.read_custom_message(msg_type, msg_reader) { + Ok(Some(msg)) => { + message = Some(msg); + Ok(true) + }, + Ok(None) => Ok(false), + Err(e) => Err(e), + } }); rd.eat_remaining().map_err(|_| DecodeError::ShortRead)?; match read_adapter { None => return Err(DecodeError::InvalidValue), Some(ChaChaPolyReadAdapter { readable: ControlTlvs::Forward(tlvs)}) => { + if message_type.is_some() { + return Err(DecodeError::InvalidValue) + } Ok(Payload::Forward(ForwardControlTlvs::Unblinded(tlvs))) }, Some(ChaChaPolyReadAdapter { readable: ControlTlvs::Receive(tlvs)}) => { - Ok(Payload::Receive { control_tlvs: ReceiveControlTlvs::Unblinded(tlvs), reply_path }) - }, + if message.is_none() { return Err(DecodeError::InvalidValue) } + Ok(Payload::Receive { + control_tlvs: ReceiveControlTlvs::Unblinded(tlvs), + reply_path, + message: OnionMessageContents::Custom(message.unwrap()), + }) + } } } } @@ -197,7 +255,7 @@ impl ReadableArgs for Payload { /// When reading a packet off the wire, we don't know a priori whether the packet is to be forwarded /// or received. Thus we read a ControlTlvs rather than reading a ForwardControlTlvs or /// ReceiveControlTlvs directly. -pub(super) enum ControlTlvs { +pub(crate) enum ControlTlvs { /// This onion message is intended to be forwarded. Forward(ForwardTlvs), /// This onion message is intended to be received.