Merge pull request #1326 from Psycho-Pirate/peers
[rust-lightning] / lightning / src / ln / peer_channel_encryptor.rs
index 111c86ecae30a6afba8c8d61f1fae9ef72bea40c..fbd32526ea658470f810c487bcb88da608904e8b 100644 (file)
@@ -1,7 +1,18 @@
+// This file is Copyright its original authors, visible in version control
+// history.
+//
+// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
+// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
+// You may not use this file except in accordance with one or both of these
+// licenses.
+
+use prelude::*;
+
 use ln::msgs::LightningError;
 use ln::msgs;
 
-use bitcoin::hashes::{Hash, HashEngine, Hmac, HmacEngine};
+use bitcoin::hashes::{Hash, HashEngine};
 use bitcoin::hashes::sha256::Hash as Sha256;
 
 use bitcoin::secp256k1::Secp256k1;
@@ -10,12 +21,13 @@ use bitcoin::secp256k1::ecdh::SharedSecret;
 use bitcoin::secp256k1;
 
 use util::chacha20poly1305rfc::ChaCha20Poly1305RFC;
-use util::byte_utils;
+use util::crypto::hkdf_extract_expand_twice;
+use bitcoin::hashes::hex::ToHex;
 
 /// Maximum Lightning message data length according to
 /// [BOLT-8](https://github.com/lightningnetwork/lightning-rfc/blob/v1.0/08-transport.md#lightning-message-specification)
 /// and [BOLT-1](https://github.com/lightningnetwork/lightning-rfc/blob/master/01-messaging.md#lightning-message-format):
-pub const LN_MAX_MSG_LEN: usize = ::std::u16::MAX as usize; // Must be equal to 65535
+pub const LN_MAX_MSG_LEN: usize = ::core::u16::MAX as usize; // Must be equal to 65535
 
 // Sha256("Noise_XK_secp256k1_ChaChaPoly_SHA256")
 const NOISE_CK: [u8; 32] = [0x26, 0x40, 0xf5, 0x2e, 0xeb, 0xcd, 0x9e, 0x88, 0x29, 0x58, 0x95, 0x1c, 0x79, 0x42, 0x50, 0xee, 0xdb, 0x28, 0x00, 0x2c, 0x05, 0xd7, 0xdc, 0x2e, 0xa0, 0xf1, 0x95, 0x40, 0x60, 0x42, 0xca, 0xf1];
@@ -85,14 +97,14 @@ impl PeerChannelEncryptor {
 
                PeerChannelEncryptor {
                        their_node_id: Some(their_node_id),
-                       secp_ctx: secp_ctx,
+                       secp_ctx,
                        noise_state: NoiseState::InProgress {
                                state: NoiseStep::PreActOne,
                                directional_state: DirectionalNoiseState::Outbound {
                                        ie: ephemeral_key,
                                },
                                bidirectional_state: BidirectionalNoiseState {
-                                       h: h,
+                                       h,
                                        ck: NOISE_CK,
                                },
                        }
@@ -110,7 +122,7 @@ impl PeerChannelEncryptor {
 
                PeerChannelEncryptor {
                        their_node_id: None,
-                       secp_ctx: secp_ctx,
+                       secp_ctx,
                        noise_state: NoiseState::InProgress {
                                state: NoiseStep::PreActOne,
                                directional_state: DirectionalNoiseState::Inbound {
@@ -119,7 +131,7 @@ impl PeerChannelEncryptor {
                                        temp_k2: None,
                                },
                                bidirectional_state: BidirectionalNoiseState {
-                                       h: h,
+                                       h,
                                        ck: NOISE_CK,
                                },
                        }
@@ -129,7 +141,7 @@ impl PeerChannelEncryptor {
        #[inline]
        fn encrypt_with_ad(res: &mut[u8], n: u64, key: &[u8; 32], h: &[u8], plaintext: &[u8]) {
                let mut nonce = [0; 12];
-               nonce[4..].copy_from_slice(&byte_utils::le64_to_array(n));
+               nonce[4..].copy_from_slice(&n.to_le_bytes()[..]);
 
                let mut chacha = ChaCha20Poly1305RFC::new(key, &nonce, h);
                let mut tag = [0; 16];
@@ -140,31 +152,18 @@ impl PeerChannelEncryptor {
        #[inline]
        fn decrypt_with_ad(res: &mut[u8], n: u64, key: &[u8; 32], h: &[u8], cyphertext: &[u8]) -> Result<(), LightningError> {
                let mut nonce = [0; 12];
-               nonce[4..].copy_from_slice(&byte_utils::le64_to_array(n));
+               nonce[4..].copy_from_slice(&n.to_le_bytes()[..]);
 
                let mut chacha = ChaCha20Poly1305RFC::new(key, &nonce, h);
                if !chacha.decrypt(&cyphertext[0..cyphertext.len() - 16], res, &cyphertext[cyphertext.len() - 16..]) {
-                       return Err(LightningError{err: "Bad MAC", action: msgs::ErrorAction::DisconnectPeer{ msg: None }});
+                       return Err(LightningError{err: "Bad MAC".to_owned(), action: msgs::ErrorAction::DisconnectPeer{ msg: None }});
                }
                Ok(())
        }
 
-       fn hkdf_extract_expand(salt: &[u8], ikm: &[u8]) -> ([u8; 32], [u8; 32]) {
-               let mut hmac = HmacEngine::<Sha256>::new(salt);
-               hmac.input(ikm);
-               let prk = Hmac::from_engine(hmac).into_inner();
-               let mut hmac = HmacEngine::<Sha256>::new(&prk[..]);
-               hmac.input(&[1; 1]);
-               let t1 = Hmac::from_engine(hmac).into_inner();
-               let mut hmac = HmacEngine::<Sha256>::new(&prk[..]);
-               hmac.input(&t1);
-               hmac.input(&[2; 1]);
-               (t1, Hmac::from_engine(hmac).into_inner())
-       }
-
        #[inline]
        fn hkdf(state: &mut BidirectionalNoiseState, ss: SharedSecret) -> [u8; 32] {
-               let (t1, t2) = Self::hkdf_extract_expand(&state.ck, &ss[..]);
+               let (t1, t2) = hkdf_extract_expand_twice(&state.ck, &ss[..]);
                state.ck = t1;
                t2
        }
@@ -198,11 +197,11 @@ impl PeerChannelEncryptor {
                assert_eq!(act.len(), 50);
 
                if act[0] != 0 {
-                       return Err(LightningError{err: "Unknown handshake version number", action: msgs::ErrorAction::DisconnectPeer{ msg: None }});
+                       return Err(LightningError{err: format!("Unknown handshake version number {}", act[0]), action: msgs::ErrorAction::DisconnectPeer{ msg: None }});
                }
 
                let their_pub = match PublicKey::from_slice(&act[1..34]) {
-                       Err(_) => return Err(LightningError{err: "Invalid public key", action: msgs::ErrorAction::DisconnectPeer{ msg: None }}),
+                       Err(_) => return Err(LightningError{err: format!("Invalid public key {}", &act[1..34].to_hex()), action: msgs::ErrorAction::DisconnectPeer{ msg: None }}),
                        Ok(key) => key,
                };
 
@@ -300,7 +299,7 @@ impl PeerChannelEncryptor {
                                                let temp_k = PeerChannelEncryptor::hkdf(bidirectional_state, ss);
 
                                                PeerChannelEncryptor::encrypt_with_ad(&mut res[50..], 0, &temp_k, &bidirectional_state.h, &[0; 0]);
-                                               final_hkdf = Self::hkdf_extract_expand(&bidirectional_state.ck, &[0; 0]);
+                                               final_hkdf = hkdf_extract_expand_twice(&bidirectional_state.ck, &[0; 0]);
                                                ck = bidirectional_state.ck.clone();
                                                res
                                        },
@@ -311,10 +310,10 @@ impl PeerChannelEncryptor {
 
                let (sk, rk) = final_hkdf;
                self.noise_state = NoiseState::Finished {
-                       sk: sk,
+                       sk,
                        sn: 0,
                        sck: ck.clone(),
-                       rk: rk,
+                       rk,
                        rn: 0,
                        rck: ck,
                };
@@ -335,14 +334,14 @@ impl PeerChannelEncryptor {
                                                        panic!("Requested act at wrong step");
                                                }
                                                if act_three[0] != 0 {
-                                                       return Err(LightningError{err: "Unknown handshake version number", action: msgs::ErrorAction::DisconnectPeer{ msg: None }});
+                                                       return Err(LightningError{err: format!("Unknown handshake version number {}", act_three[0]), action: msgs::ErrorAction::DisconnectPeer{ msg: None }});
                                                }
 
                                                let mut their_node_id = [0; 33];
                                                PeerChannelEncryptor::decrypt_with_ad(&mut their_node_id, 1, &temp_k2.unwrap(), &bidirectional_state.h, &act_three[1..50])?;
                                                self.their_node_id = Some(match PublicKey::from_slice(&their_node_id) {
                                                        Ok(key) => key,
-                                                       Err(_) => return Err(LightningError{err: "Bad node_id from peer", action: msgs::ErrorAction::DisconnectPeer{ msg: None }}),
+                                                       Err(_) => return Err(LightningError{err: format!("Bad node_id from peer, {}", &their_node_id.to_hex()), action: msgs::ErrorAction::DisconnectPeer{ msg: None }}),
                                                });
 
                                                let mut sha = Sha256::engine();
@@ -354,7 +353,7 @@ impl PeerChannelEncryptor {
                                                let temp_k = PeerChannelEncryptor::hkdf(bidirectional_state, ss);
 
                                                PeerChannelEncryptor::decrypt_with_ad(&mut [0; 0], 0, &temp_k, &bidirectional_state.h, &act_three[50..])?;
-                                               final_hkdf = Self::hkdf_extract_expand(&bidirectional_state.ck, &[0; 0]);
+                                               final_hkdf = hkdf_extract_expand_twice(&bidirectional_state.ck, &[0; 0]);
                                                ck = bidirectional_state.ck.clone();
                                        },
                                        _ => panic!("Wrong direction for act"),
@@ -364,10 +363,10 @@ impl PeerChannelEncryptor {
 
                let (rk, sk) = final_hkdf;
                self.noise_state = NoiseState::Finished {
-                       sk: sk,
+                       sk,
                        sn: 0,
                        sck: ck.clone(),
-                       rk: rk,
+                       rk,
                        rn: 0,
                        rck: ck,
                };
@@ -388,13 +387,13 @@ impl PeerChannelEncryptor {
                match self.noise_state {
                        NoiseState::Finished { ref mut sk, ref mut sn, ref mut sck, rk: _, rn: _, rck: _ } => {
                                if *sn >= 1000 {
-                                       let (new_sck, new_sk) = Self::hkdf_extract_expand(sck, sk);
+                                       let (new_sck, new_sk) = hkdf_extract_expand_twice(sck, sk);
                                        *sck = new_sck;
                                        *sk = new_sk;
                                        *sn = 0;
                                }
 
-                               Self::encrypt_with_ad(&mut res[0..16+2], *sn, sk, &[0; 0], &byte_utils::be16_to_array(msg.len() as u16));
+                               Self::encrypt_with_ad(&mut res[0..16+2], *sn, sk, &[0; 0], &(msg.len() as u16).to_be_bytes());
                                *sn += 1;
 
                                Self::encrypt_with_ad(&mut res[16+2..], *sn, sk, &[0; 0], msg);
@@ -414,7 +413,7 @@ impl PeerChannelEncryptor {
                match self.noise_state {
                        NoiseState::Finished { sk: _, sn: _, sck: _, ref mut rk, ref mut rn, ref mut rck } => {
                                if *rn >= 1000 {
-                                       let (new_rck, new_rk) = Self::hkdf_extract_expand(rck, rk);
+                                       let (new_rck, new_rk) = hkdf_extract_expand_twice(rck, rk);
                                        *rck = new_rck;
                                        *rk = new_rk;
                                        *rn = 0;
@@ -423,7 +422,7 @@ impl PeerChannelEncryptor {
                                let mut res = [0; 2];
                                Self::decrypt_with_ad(&mut res, *rn, rk, &[0; 0], msg)?;
                                *rn += 1;
-                               Ok(byte_utils::slice_to_be16(&res))
+                               Ok(u16::from_be_bytes(res))
                        },
                        _ => panic!("Tried to decrypt a message prior to noise handshake completion"),
                }
@@ -705,7 +704,7 @@ mod tests {
        #[test]
        fn max_msg_len_limit_value() {
                assert_eq!(LN_MAX_MSG_LEN, 65535);
-               assert_eq!(LN_MAX_MSG_LEN, ::std::u16::MAX as usize);
+               assert_eq!(LN_MAX_MSG_LEN, ::core::u16::MAX as usize);
        }
 
        #[test]