X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fln%2Finbound_payment.rs;h=1b0fd1707b8c664fd0b37cbc25bad67ef0704085;hb=e94647ca4ebc63be4a8164804d08cf37e4655d6c;hp=0c6d6f2b804bccd8cfb651c24995bf4959998a91;hpb=3bd395f2a8a7398d7bf5ad9b2c7257e64f9c126b;p=rust-lightning diff --git a/lightning/src/ln/inbound_payment.rs b/lightning/src/ln/inbound_payment.rs index 0c6d6f2b..1b0fd170 100644 --- a/lightning/src/ln/inbound_payment.rs +++ b/lightning/src/ln/inbound_payment.rs @@ -14,19 +14,19 @@ use bitcoin::hashes::{Hash, HashEngine}; use bitcoin::hashes::cmp::fixed_time_eq; use bitcoin::hashes::hmac::{Hmac, HmacEngine}; use bitcoin::hashes::sha256::Hash as Sha256; -use crate::chain::keysinterface::{KeyMaterial, EntropySource}; +use crate::sign::{KeyMaterial, EntropySource}; use crate::ln::{PaymentHash, PaymentPreimage, PaymentSecret}; use crate::ln::msgs; use crate::ln::msgs::MAX_VALUE_MSAT; use crate::util::chacha20::ChaCha20; -use crate::util::crypto::hkdf_extract_expand_thrice; +use crate::util::crypto::hkdf_extract_expand_4x; use crate::util::errors::APIError; use crate::util::logger::Logger; -use core::convert::TryInto; +use core::convert::{TryFrom, TryInto}; use core::ops::Deref; -const IV_LEN: usize = 16; +pub(crate) const IV_LEN: usize = 16; const METADATA_LEN: usize = 16; const METADATA_KEY_LEN: usize = 32; const AMT_MSAT_LEN: usize = 8; @@ -37,7 +37,7 @@ const METHOD_TYPE_OFFSET: usize = 5; /// A set of keys that were HKDF-expanded from an initial call to /// [`NodeSigner::get_inbound_payment_key_material`]. /// -/// [`NodeSigner::get_inbound_payment_key_material`]: crate::chain::keysinterface::NodeSigner::get_inbound_payment_key_material +/// [`NodeSigner::get_inbound_payment_key_material`]: crate::sign::NodeSigner::get_inbound_payment_key_material pub struct ExpandedKey { /// The key used to encrypt the bytes containing the payment metadata (i.e. the amount and /// expiry, included for payment verification on decryption). @@ -48,6 +48,8 @@ pub struct ExpandedKey { /// The key used to authenticate a user-provided payment hash and metadata as previously /// registered with LDK. user_pmt_hash_key: [u8; 32], + /// The base key used to derive signing keys and authenticate messages for BOLT 12 Offers. + offers_base_key: [u8; 32], } impl ExpandedKey { @@ -55,14 +57,76 @@ impl ExpandedKey { /// /// It is recommended to cache this value and not regenerate it for each new inbound payment. pub fn new(key_material: &KeyMaterial) -> ExpandedKey { - let (metadata_key, ldk_pmt_hash_key, user_pmt_hash_key) = - hkdf_extract_expand_thrice(b"LDK Inbound Payment Key Expansion", &key_material.0); + let (metadata_key, ldk_pmt_hash_key, user_pmt_hash_key, offers_base_key) = + hkdf_extract_expand_4x(b"LDK Inbound Payment Key Expansion", &key_material.0); Self { metadata_key, ldk_pmt_hash_key, user_pmt_hash_key, + offers_base_key, } } + + /// Returns an [`HmacEngine`] used to construct [`Offer::metadata`]. + /// + /// [`Offer::metadata`]: crate::offers::offer::Offer::metadata + #[allow(unused)] + pub(crate) fn hmac_for_offer( + &self, nonce: Nonce, iv_bytes: &[u8; IV_LEN] + ) -> HmacEngine { + let mut hmac = HmacEngine::::new(&self.offers_base_key); + hmac.input(iv_bytes); + hmac.input(&nonce.0); + hmac + } +} + +/// A 128-bit number used only once. +/// +/// Needed when constructing [`Offer::metadata`] and deriving [`Offer::signing_pubkey`] from +/// [`ExpandedKey`]. Must not be reused for any other derivation without first hashing. +/// +/// [`Offer::metadata`]: crate::offers::offer::Offer::metadata +/// [`Offer::signing_pubkey`]: crate::offers::offer::Offer::signing_pubkey +#[allow(unused)] +#[derive(Clone, Copy, Debug, PartialEq)] +pub(crate) struct Nonce(pub(crate) [u8; Self::LENGTH]); + +impl Nonce { + /// Number of bytes in the nonce. + pub const LENGTH: usize = 16; + + /// Creates a `Nonce` from the given [`EntropySource`]. + pub fn from_entropy_source(entropy_source: ES) -> Self + where + ES::Target: EntropySource, + { + let mut bytes = [0u8; Self::LENGTH]; + let rand_bytes = entropy_source.get_secure_random_bytes(); + bytes.copy_from_slice(&rand_bytes[..Self::LENGTH]); + + Nonce(bytes) + } + + /// Returns a slice of the underlying bytes of size [`Nonce::LENGTH`]. + pub fn as_slice(&self) -> &[u8] { + &self.0 + } +} + +impl TryFrom<&[u8]> for Nonce { + type Error = (); + + fn try_from(bytes: &[u8]) -> Result { + if bytes.len() != Self::LENGTH { + return Err(()); + } + + let mut copied_bytes = [0u8; Self::LENGTH]; + copied_bytes.copy_from_slice(bytes); + + Ok(Self(copied_bytes)) + } } enum Method { @@ -102,8 +166,8 @@ fn min_final_cltv_expiry_delta_from_metadata(bytes: [u8; METADATA_LEN]) -> u16 { /// Note that if `min_final_cltv_expiry_delta` is set to some value, then the payment will not be receivable /// on versions of LDK prior to 0.0.114. /// -/// [phantom node payments]: crate::chain::keysinterface::PhantomKeysManager -/// [`NodeSigner::get_inbound_payment_key_material`]: crate::chain::keysinterface::NodeSigner::get_inbound_payment_key_material +/// [phantom node payments]: crate::sign::PhantomKeysManager +/// [`NodeSigner::get_inbound_payment_key_material`]: crate::sign::NodeSigner::get_inbound_payment_key_material pub fn create(keys: &ExpandedKey, min_value_msat: Option, invoice_expiry_delta_secs: u32, entropy_source: &ES, current_time: u64, min_final_cltv_expiry_delta: Option) -> Result<(PaymentHash, PaymentSecret), ()> @@ -138,7 +202,7 @@ pub fn create(keys: &ExpandedKey, min_value_msat: Option, /// Note that if `min_final_cltv_expiry_delta` is set to some value, then the payment will not be receivable /// on versions of LDK prior to 0.0.114. /// -/// [phantom node payments]: crate::chain::keysinterface::PhantomKeysManager +/// [phantom node payments]: crate::sign::PhantomKeysManager pub fn create_from_hash(keys: &ExpandedKey, min_value_msat: Option, payment_hash: PaymentHash, invoice_expiry_delta_secs: u32, current_time: u64, min_final_cltv_expiry_delta: Option) -> Result { let metadata_bytes = construct_metadata_bytes(min_value_msat, if min_final_cltv_expiry_delta.is_some() { @@ -247,7 +311,7 @@ fn construct_payment_secret(iv_bytes: &[u8; IV_LEN], metadata_bytes: &[u8; METAD /// /// See [`ExpandedKey`] docs for more info on the individual keys used. /// -/// [`NodeSigner::get_inbound_payment_key_material`]: crate::chain::keysinterface::NodeSigner::get_inbound_payment_key_material +/// [`NodeSigner::get_inbound_payment_key_material`]: crate::sign::NodeSigner::get_inbound_payment_key_material /// [`create_inbound_payment`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment /// [`create_inbound_payment_for_hash`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment_for_hash pub(super) fn verify(payment_hash: PaymentHash, payment_data: &msgs::FinalOnionHopData,