use secp256k1;
use crypto::hkdf::{hkdf_extract,hkdf_expand};
+use crypto::digest::Digest;
use util::sha2::Sha256;
use util::logger::Logger;
+use util::rng;
+use util::byte_utils;
+use std::time::{SystemTime, UNIX_EPOCH};
use std::sync::Arc;
+use std::sync::atomic::{AtomicUsize, Ordering};
/// When on-chain outputs are created by rust-lightning an event is generated which informs the
/// user thereof. This enum describes the format of the output and provides the OutPoint.
/// The output which is referenced by the given outpoint
output: TxOut,
},
- /// Outpoint commits to a P2WSH, should be spend by the following witness :
+ /// Outpoint commits to a P2WSH
+ /// P2WSH should be spend by the following witness :
/// <local_delayedsig> 0 <witnessScript>
/// With input nSequence set to_self_delay.
- /// Outputs from a HTLC-Success/Timeout tx
- DynamicOutput {
+ /// Outputs from a HTLC-Success/Timeout tx/commitment tx
+ DynamicOutputP2WSH {
/// Outpoint spendable by user wallet
outpoint: OutPoint,
- /// local_delayedkey = delayed_payment_basepoint_secret + SHA256(per_commitment_point || delayed_payment_basepoint
- local_delayedkey: SecretKey,
- /// witness redeemScript encumbering output
+ /// local_delayedkey = delayed_payment_basepoint_secret + SHA256(per_commitment_point || delayed_payment_basepoint) OR
+ key: SecretKey,
+ /// witness redeemScript encumbering output.
witness_script: Script,
/// nSequence input must commit to self_delay to satisfy script's OP_CSV
to_self_delay: u16,
+ /// The output which is referenced by the given outpoint
+ output: TxOut,
+ },
+ /// Outpoint commits to a P2WPKH
+ /// P2WPKH should be spend by the following witness :
+ /// <local_sig> <local_pubkey>
+ /// Outputs to_remote from a commitment tx
+ DynamicOutputP2WPKH {
+ /// Outpoint spendable by user wallet
+ outpoint: OutPoint,
+ /// localkey = payment_basepoint_secret + SHA256(per_commitment_point || payment_basepoint
+ key: SecretKey,
+ /// The output which is reference by the given outpoint
+ output: TxOut,
}
}
/// Get a new set of ChannelKeys for per-channel secrets. These MUST be unique even if you
/// restarted with some stale data!
fn get_channel_keys(&self, inbound: bool) -> ChannelKeys;
+ /// Get a secret for construting an onion packet
+ fn get_session_key(&self) -> SecretKey;
}
/// Set of lightning keys needed to operate a channel as described in BOLT 3
destination_script: Script,
shutdown_pubkey: PublicKey,
channel_master_key: ExtendedPrivKey,
+ channel_child_index: AtomicUsize,
+ session_master_key: ExtendedPrivKey,
+ session_child_index: AtomicUsize,
logger: Arc<Logger>,
}
Err(_) => panic!("Your RNG is busted"),
};
let channel_master_key = master_key.ckd_priv(&secp_ctx, ChildNumber::from_hardened_idx(3)).expect("Your RNG is busted");
+ let session_master_key = master_key.ckd_priv(&secp_ctx, ChildNumber::from_hardened_idx(4)).expect("Your RNG is busted");
KeysManager {
secp_ctx,
node_secret,
destination_script,
shutdown_pubkey,
channel_master_key,
+ channel_child_index: AtomicUsize::new(0),
+ session_master_key,
+ session_child_index: AtomicUsize::new(0),
logger,
}
}
fn get_channel_keys(&self, _inbound: bool) -> ChannelKeys {
- let channel_pubkey = ExtendedPubKey::from_private(&self.secp_ctx, &self. channel_master_key);
- let mut seed = [0; 32];
- for (arr, slice) in seed.iter_mut().zip((&channel_pubkey.public_key.serialize()[0..32]).iter()) {
- *arr = *slice;
- }
+ // We only seriously intend to rely on the channel_master_key for true secure
+ // entropy, everything else just ensures uniqueness. We generally don't expect
+ // all clients to have non-broken RNGs here, so we also include the current
+ // time as a fallback to get uniqueness.
+ let mut sha = Sha256::new();
+
+ let mut seed = [0u8; 32];
+ rng::fill_bytes(&mut seed[..]);
+ sha.input(&seed);
+
+ let now = SystemTime::now().duration_since(UNIX_EPOCH).expect("Time went backwards");
+ sha.input(&byte_utils::be32_to_array(now.subsec_nanos()));
+ sha.input(&byte_utils::be64_to_array(now.as_secs()));
+
+ let child_ix = self.channel_child_index.fetch_add(1, Ordering::AcqRel);
+ let child_privkey = self.channel_master_key.ckd_priv(&self.secp_ctx, ChildNumber::from_hardened_idx(child_ix as u32)).expect("Your RNG is busted");
+ sha.input(&child_privkey.secret_key[..]);
+
+ sha.result(&mut seed);
ChannelKeys::new_from_seed(&seed)
}
+
+ fn get_session_key(&self) -> SecretKey {
+ let mut sha = Sha256::new();
+ let mut res = [0u8; 32];
+
+ let now = SystemTime::now().duration_since(UNIX_EPOCH).expect("Time went backwards");
+ sha.input(&byte_utils::be32_to_array(now.subsec_nanos()));
+ sha.input(&byte_utils::be64_to_array(now.as_secs()));
+
+ let child_ix = self.session_child_index.fetch_add(1, Ordering::AcqRel);
+ let child_privkey = self.session_master_key.ckd_priv(&self.secp_ctx, ChildNumber::from_hardened_idx(child_ix as u32)).expect("Your RNG is busted");
+ sha.input(&child_privkey.secret_key[..]);
+ sha.result(&mut res);
+ SecretKey::from_slice(&self.secp_ctx, &res).expect("Your RNG is busted")
+ }
}