Implementing proof of reserves

Author: ulrichard

.gitignore

@@ -3,3 +3,5 @@ Cargo.lock
 
 *.swp
 .idea
+
+.vscode/

CHANGELOG.md

@@ -11,6 +11,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Bitcoin core RPC added as blockchain backend
 - Add a `verify` feature that can be enable to verify the unconfirmed txs we download against the consensus rules
 
+### Proof of reserves
+- Added a separate module to construct "proof of reserve" PSBTs, and verify them.
+
 ## [v0.8.0] - [v0.7.0]
 
 ### Wallet

Cargo.toml

@@ -32,6 +32,8 @@ socks = { version = "0.3", optional = true }
 lazy_static = { version = "1.4", optional = true }
 tiny-bip39 = { version = "^0.8", optional = true }
 bitcoinconsensus = { version = "0.19.0-3", optional = true }
+bitcoin_hashes = { version = "^0.9", optional = true }
+base64 = { version = "^0.11", optional = true }
 
 # Needed by bdk_blockchain_tests macro
 bitcoincore-rpc = { version = "0.13", optional = true }
@@ -59,7 +61,7 @@ async-interface = ["async-trait"]
 all-keys = ["keys-bip39"]
 keys-bip39 = ["tiny-bip39"]
 rpc = ["bitcoincore-rpc"]
-
+reserves = ["bitcoinconsensus", "bitcoin_hashes", "base64"]
 
 # Debug/Test features
 test-blockchains = ["bitcoincore-rpc", "electrum-client"]
@@ -74,6 +76,7 @@ env_logger = "0.7"
 clap = "2.33"
 serial_test = "0.4"
 bitcoind = "0.10.0"
+rstest = "^0.7"
 
 [[example]]
 name = "address_validator"

src/error.rs

@@ -67,6 +67,10 @@ pub enum Error {
     },
     /// Node doesn't have data to estimate a fee rate
     FeeRateUnavailable,
+    /// The proof of reserves is invalid. The reason is given in the string parameter.
+    ProofOfReservesInvalid(String),
+    /// Cannot verify the proof.
+    CannotVerifyProof,
     /// In order to use the [`TxBuilder::add_global_xpubs`] option every extended
     /// key in the descriptor must either be a master key itself (having depth = 0) or have an
     /// explicit origin provided

src/wallet/mod.rs

@@ -38,6 +38,8 @@ use log::{debug, error, info, trace};
 pub mod address_validator;
 pub mod coin_selection;
 pub mod export;
+#[cfg(feature = "reserves")]
+pub mod reserves;
 pub mod signer;
 pub mod time;
 pub mod tx_builder;