From f19821dac4114f4329d997b4087141d8080821f3 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Daniel=20Granh=C3=A3o?= Date: Thu, 26 Jan 2023 10:32:14 +0000 Subject: [PATCH] Use `Chacha20` in `get_secure_random_bytes()` --- lightning/src/chain/keysinterface.rs | 34 ++++++++++++---------------- lightning/src/ln/functional_tests.rs | 4 ++-- 2 files changed, 17 insertions(+), 21 deletions(-) diff --git a/lightning/src/chain/keysinterface.rs b/lightning/src/chain/keysinterface.rs index d1b75f868..a2611e7df 100644 --- a/lightning/src/chain/keysinterface.rs +++ b/lightning/src/chain/keysinterface.rs @@ -21,7 +21,6 @@ use bitcoin::util::sighash; use bitcoin::bech32::u5; use bitcoin::hashes::{Hash, HashEngine}; -use bitcoin::hashes::sha256::HashEngine as Sha256State; use bitcoin::hashes::sha256::Hash as Sha256; use bitcoin::hashes::sha256d::Hash as Sha256dHash; use bitcoin::hash_types::WPubkeyHash; @@ -49,6 +48,8 @@ use core::convert::TryInto; use core::sync::atomic::{AtomicUsize, Ordering}; use crate::io::{self, Error}; use crate::ln::msgs::{DecodeError, MAX_VALUE_MSAT}; +use crate::util::atomic_counter::AtomicCounter; +use crate::util::chacha20::ChaCha20; use crate::util::invoice::construct_invoice_preimage; /// Used as initial key material, to be expanded into multiple secret keys (but not to be used @@ -979,9 +980,8 @@ pub struct KeysManager { channel_master_key: ExtendedPrivKey, channel_child_index: AtomicUsize, - rand_bytes_master_key: ExtendedPrivKey, - rand_bytes_child_index: AtomicUsize, - rand_bytes_unique_start: Sha256State, + rand_bytes_unique_start: [u8; 32], + rand_bytes_index: AtomicCounter, seed: [u8; 32], starting_time_secs: u64, @@ -1027,15 +1027,16 @@ impl KeysManager { Err(_) => panic!("Your RNG is busted"), }; let channel_master_key = master_key.ckd_priv(&secp_ctx, ChildNumber::from_hardened_idx(3).unwrap()).expect("Your RNG is busted"); - let rand_bytes_master_key = master_key.ckd_priv(&secp_ctx, ChildNumber::from_hardened_idx(4).unwrap()).expect("Your RNG is busted"); let inbound_payment_key: SecretKey = master_key.ckd_priv(&secp_ctx, ChildNumber::from_hardened_idx(5).unwrap()).expect("Your RNG is busted").private_key; let mut inbound_pmt_key_bytes = [0; 32]; inbound_pmt_key_bytes.copy_from_slice(&inbound_payment_key[..]); - let mut rand_bytes_unique_start = Sha256::engine(); - rand_bytes_unique_start.input(&starting_time_secs.to_be_bytes()); - rand_bytes_unique_start.input(&starting_time_nanos.to_be_bytes()); - rand_bytes_unique_start.input(seed); + let mut rand_bytes_engine = Sha256::engine(); + rand_bytes_engine.input(&starting_time_secs.to_be_bytes()); + rand_bytes_engine.input(&starting_time_nanos.to_be_bytes()); + rand_bytes_engine.input(seed); + rand_bytes_engine.input(b"LDK PRNG Seed"); + let rand_bytes_unique_start = Sha256::from_engine(rand_bytes_engine).into_inner(); let mut res = KeysManager { secp_ctx, @@ -1049,9 +1050,8 @@ impl KeysManager { channel_master_key, channel_child_index: AtomicUsize::new(0), - rand_bytes_master_key, - rand_bytes_child_index: AtomicUsize::new(0), rand_bytes_unique_start, + rand_bytes_index: AtomicCounter::new(), seed: *seed, starting_time_secs, @@ -1248,14 +1248,10 @@ impl KeysManager { impl EntropySource for KeysManager { fn get_secure_random_bytes(&self) -> [u8; 32] { - let mut sha = self.rand_bytes_unique_start.clone(); - - let child_ix = self.rand_bytes_child_index.fetch_add(1, Ordering::AcqRel); - let child_privkey = self.rand_bytes_master_key.ckd_priv(&self.secp_ctx, ChildNumber::from_hardened_idx(child_ix as u32).expect("key space exhausted")).expect("Your RNG is busted"); - sha.input(&child_privkey.private_key[..]); - - sha.input(b"Unique Secure Random Bytes Salt"); - Sha256::from_engine(sha).into_inner() + let index = self.rand_bytes_index.get_increment(); + let mut nonce = [0u8; 16]; + nonce[..8].copy_from_slice(&index.to_be_bytes()); + ChaCha20::get_single_block(&self.rand_bytes_unique_start, &nonce) } } diff --git a/lightning/src/ln/functional_tests.rs b/lightning/src/ln/functional_tests.rs index 8b71837d4..70b0f1da7 100644 --- a/lightning/src/ln/functional_tests.rs +++ b/lightning/src/ln/functional_tests.rs @@ -7252,8 +7252,8 @@ fn test_bump_penalty_txn_on_revoked_htlcs() { assert_ne!(node_txn[0].input[0].previous_output, node_txn[2].input[0].previous_output); assert_ne!(node_txn[1].input[0].previous_output, node_txn[2].input[0].previous_output); - assert_eq!(node_txn[0].input[0].previous_output, revoked_htlc_txn[0].input[0].previous_output); - assert_eq!(node_txn[1].input[0].previous_output, revoked_htlc_txn[1].input[0].previous_output); + assert_eq!(node_txn[0].input[0].previous_output, revoked_htlc_txn[1].input[0].previous_output); + assert_eq!(node_txn[1].input[0].previous_output, revoked_htlc_txn[0].input[0].previous_output); // node_txn[3] spends the revoked outputs from the revoked_htlc_txn (which only have one // output, checked above). -- 2.39.5