From 7ea39a13b2620253123aa93c63b7f9a58a8df762 Mon Sep 17 00:00:00 2001
From: Matt Corallo <git@bluematt.me>
Date: Tue, 18 Dec 2018 00:01:31 -0500
Subject: [PATCH] Use bitcoin_hashes' fixed_time_eq, removing the rust-crypto
 dep

---
 Cargo.toml                         |  5 -----
 build.rs                           | 10 ----------
 fuzz/Cargo.toml                    |  1 -
 src/lib.rs                         |  1 -
 src/ln/channelmanager.rs           |  7 +++----
 src/util/chacha20poly1305rfc.rs    |  3 +--
 src/util/rust_crypto_nonstd_arch.c | 13 -------------
 7 files changed, 4 insertions(+), 36 deletions(-)
 delete mode 100644 build.rs
 delete mode 100644 src/util/rust_crypto_nonstd_arch.c

diff --git a/Cargo.toml b/Cargo.toml
index a14984a0..e012639d 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -9,7 +9,6 @@ A Bitcoin Lightning library in Rust.
 Does most of the hard work, without implying a specific runtime, requiring clients implement basic network logic, chain interactions and disk storage.
 Still missing tons of error-handling. See GitHub issues for suggested projects if you want to contribute. Don't have to bother telling you not to use this for anything serious, because you'd have to build a client around it to even try.
 """
-build = "build.rs"
 
 [features]
 # Supports tracking channels with a non-bitcoin chain hashes. Currently enables all kinds of fun DoS attacks.
@@ -25,13 +24,9 @@ max_level_debug = []
 [dependencies]
 bitcoin = "0.15"
 bitcoin_hashes = { git = "https://github.com/TheBlueMatt/bitcoin_hashes", branch = "rust-lightning-dep" }
-rust-crypto = "0.2"
 rand = "0.4"
 secp256k1 = "0.11"
 
-[build-dependencies]
-cc = "1.0"
-
 [dev-dependencies.bitcoin]
 version = "0.15"
 features = ["bitcoinconsensus"]
diff --git a/build.rs b/build.rs
deleted file mode 100644
index 963075e9..00000000
--- a/build.rs
+++ /dev/null
@@ -1,10 +0,0 @@
-extern crate cc;
-
-fn main() {
-	#[cfg(not(any(target_arch = "x86", target_arch = "x86_64", target_arch = "arm")))]
-	{
-		let mut cfg = cc::Build::new();
-		cfg.file("src/util/rust_crypto_nonstd_arch.c");
-		cfg.compile("lib_rust_crypto_nonstd_arch.a");
-	}
-}
diff --git a/fuzz/Cargo.toml b/fuzz/Cargo.toml
index c1069d32..c4ed4c70 100644
--- a/fuzz/Cargo.toml
+++ b/fuzz/Cargo.toml
@@ -6,7 +6,6 @@ publish = false
 # Because the function is unused it gets dropped before we link lightning, so
 # we have to duplicate build.rs here. Note that this is only required for
 # fuzztarget mode.
-build = "../build.rs"
 
 [package.metadata]
 cargo-fuzz = true
diff --git a/src/lib.rs b/src/lib.rs
index 5564a575..ec6718e8 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -13,7 +13,6 @@
 
 extern crate bitcoin;
 extern crate bitcoin_hashes;
-extern crate crypto;
 extern crate rand;
 extern crate secp256k1;
 #[cfg(test)] extern crate hex;
diff --git a/src/ln/channelmanager.rs b/src/ln/channelmanager.rs
index e7214427..2278faae 100644
--- a/src/ln/channelmanager.rs
+++ b/src/ln/channelmanager.rs
@@ -17,6 +17,7 @@ use bitcoin::util::hash::{BitcoinHash, Sha256dHash};
 use bitcoin_hashes::{Hash, HashEngine};
 use bitcoin_hashes::hmac::{Hmac, HmacEngine};
 use bitcoin_hashes::sha256::Hash as Sha256;
+use bitcoin_hashes::cmp::fixed_time_eq;
 
 use secp256k1::key::{SecretKey,PublicKey};
 use secp256k1::{Secp256k1,Message};
@@ -39,8 +40,6 @@ use util::logger::Logger;
 use util::errors::APIError;
 use util::errors;
 
-use crypto;
-
 use std::{cmp, ptr, mem};
 use std::collections::{HashMap, hash_map, HashSet};
 use std::io::Cursor;
@@ -991,7 +990,7 @@ impl ChannelManager {
 		let mut hmac = HmacEngine::<Sha256>::new(&mu);
 		hmac.input(&msg.onion_routing_packet.hop_data);
 		hmac.input(&msg.payment_hash.0[..]);
-		if !crypto::util::fixed_time_eq(&Hmac::from_engine(hmac).into_inner(), &msg.onion_routing_packet.hmac) {
+		if !fixed_time_eq(&Hmac::from_engine(hmac).into_inner(), &msg.onion_routing_packet.hmac) {
 			return_malformed_err!("HMAC Check failed", 0x8000 | 0x4000 | 5);
 		}
 
@@ -2141,7 +2140,7 @@ impl ChannelManager {
 					let mut hmac = HmacEngine::<Sha256>::new(&um);
 					hmac.input(&err_packet.encode()[32..]);
 
-					if crypto::util::fixed_time_eq(&Hmac::from_engine(hmac).into_inner(), &err_packet.hmac) {
+					if fixed_time_eq(&Hmac::from_engine(hmac).into_inner(), &err_packet.hmac) {
 						if let Some(error_code_slice) = err_packet.failuremsg.get(0..2) {
 							const PERM: u16 = 0x4000;
 							const NODE: u16 = 0x2000;
diff --git a/src/util/chacha20poly1305rfc.rs b/src/util/chacha20poly1305rfc.rs
index ae1b069a..1d3af1ea 100644
--- a/src/util/chacha20poly1305rfc.rs
+++ b/src/util/chacha20poly1305rfc.rs
@@ -14,8 +14,7 @@
 mod real_chachapoly {
 	use util::chacha20::ChaCha20;
 	use util::poly1305::Poly1305;
-
-	use crypto::util::fixed_time_eq;
+	use bitcoin_hashes::cmp::fixed_time_eq;
 
 	use util::byte_utils;
 
diff --git a/src/util/rust_crypto_nonstd_arch.c b/src/util/rust_crypto_nonstd_arch.c
deleted file mode 100644
index f5076580..00000000
--- a/src/util/rust_crypto_nonstd_arch.c
+++ /dev/null
@@ -1,13 +0,0 @@
-#include <stdint.h>
-#include <stdlib.h>
-
-uint32_t rust_crypto_util_fixed_time_eq_asm(uint8_t* lhsp, uint8_t* rhsp, size_t count) {
-	if (count == 0) {
-		return 1;
-	}
-	uint8_t result = 0;
-	for (size_t i = 0; i < count; i++) {
-		result |= (lhsp[i] ^ rhsp[i]);
-	}
-	return result;
-}
-- 
2.30.2