Merge #757: Minimally-invasive separation of bitcoin keys from ECDSA …

…signature types

8a993e8 Properly deprecate util::ecdsa key re-exports (Dr Maxim Orlovsky)
bcb8932 Re-org keys and ecdsa mods - pt.3 (Dr Maxim Orlovsky)
d1c2213 Re-org keys and ecdsa mods - pt.2 (Dr Maxim Orlovsky)
b917016 Re-org keys and ecdsa mods - pt.1 (Dr Maxim Orlovsky)
2d9de78 Re-export all key types under `util::key`. Deprecate other exports. (Dr Maxim Orlovsky)

Pull request description:

  This PR tries to do a minimally-invazive separation of signature- and key-related types, previously mixed in a single `util::ecdsa` module.

  Rationale: bitcoin key types are not specific for signature algorithm. See discussion at #588.

  This PR became possible after we moved on new `secp256k1` version exposing `XonlyPublicKey` type, since now all key types may co-exist in a single module under different names

  The PR goal is achieved through
  - Renaming ecdsa mod into private ec module such that the code is not copied and diff size is small;
  - Introducing dummy ecdsa mod back in the next commit and re-exporiting only signature types from internal `ec` mod in it;
  - Re-exporting all key types under `key` module, removing previous depreciation message for bitcoin keys.

ACKs for top commit:
  apoelstra:
    ACK 8a993e8
  sanket1729:
    utACK 8a993e8

Tree-SHA512: 9f71edaa2cf4cdab4b239cb1d57576e2ba0fc3c2ec0ea19ae232005967b9400da6ded992b33d10b190ca617a66dca9b99be430bc5058a064f0be1489723c4a3a

src/blockdata/script.rs

@@ -39,7 +39,7 @@ use policy::DUST_RELAY_TX_FEE;
 #[cfg(feature="bitcoinconsensus")] use core::convert::From;
 #[cfg(feature="bitcoinconsensus")] use OutPoint;
 
-use util::ecdsa::PublicKey;
+use util::key::PublicKey;
 use util::address::WitnessVersion;
 use util::taproot::{LeafVersion, TapBranchHash, TapLeafHash};
 use secp256k1::{Secp256k1, Verification};
@@ -1031,7 +1031,7 @@ mod test {
     use hashes::hex::{FromHex, ToHex};
     use consensus::encode::{deserialize, serialize};
     use blockdata::opcodes;
-    use util::ecdsa::PublicKey;
+    use util::key::PublicKey;
     use util::psbt::serialize::Serialize;
 
     #[test]

src/lib.rs

@@ -138,10 +138,7 @@ pub use util::sighash::SchnorrSigHashType;
 
 pub use util::ecdsa::{self, EcdsaSig, EcdsaSigError};
 pub use util::schnorr::{self, SchnorrSig, SchnorrSigError};
-#[deprecated(since = "0.26.1", note = "Please use `ecdsa::PrivateKey` instead")]
-pub use util::ecdsa::PrivateKey;
-#[deprecated(since = "0.26.1", note = "Please use `ecdsa::PublicKey` instead")]
-pub use util::ecdsa::PublicKey;
+pub use util::key::{PrivateKey, PublicKey, XOnlyPublicKey, KeyPair};
 #[allow(deprecated)]
 pub use blockdata::transaction::SigHashType;
 

src/util/address.rs

@@ -20,13 +20,13 @@
 //! ```rust
 //! use bitcoin::network::constants::Network;
 //! use bitcoin::util::address::Address;
-//! use bitcoin::util::ecdsa;
+//! use bitcoin::PublicKey;
 //! use bitcoin::secp256k1::Secp256k1;
 //! use bitcoin::secp256k1::rand::thread_rng;
 //!
 //! // Generate random key pair.
 //! let s = Secp256k1::new();
-//! let public_key = ecdsa::PublicKey::new(s.generate_keypair(&mut thread_rng()).1);
+//! let public_key = PublicKey::new(s.generate_keypair(&mut thread_rng()).1);
 //!
 //! // Generate pay-to-pubkey-hash address.
 //! let address = Address::p2pkh(&public_key, Network::Bitcoin);
@@ -47,8 +47,8 @@ use blockdata::{script, opcodes};
 use blockdata::constants::{PUBKEY_ADDRESS_PREFIX_MAIN, SCRIPT_ADDRESS_PREFIX_MAIN, PUBKEY_ADDRESS_PREFIX_TEST, SCRIPT_ADDRESS_PREFIX_TEST, MAX_SCRIPT_ELEMENT_SIZE};
 use network::constants::Network;
 use util::base58;
-use util::ecdsa;
 use util::taproot::TapBranchHash;
+use util::key::PublicKey;
 use blockdata::script::Instruction;
 use util::schnorr::{TapTweak, UntweakedPublicKey, TweakedPublicKey};
 
@@ -408,7 +408,7 @@ impl Payload {
 
     /// Creates a pay to (compressed) public key hash payload from a public key
     #[inline]
-    pub fn p2pkh(pk: &ecdsa::PublicKey) -> Payload {
+    pub fn p2pkh(pk: &PublicKey) -> Payload {
         Payload::PubkeyHash(pk.pubkey_hash())
     }
 
@@ -422,15 +422,15 @@ impl Payload {
     }
 
     /// Create a witness pay to public key payload from a public key
-    pub fn p2wpkh(pk: &ecdsa::PublicKey) -> Result<Payload, Error> {
+    pub fn p2wpkh(pk: &PublicKey) -> Result<Payload, Error> {
         Ok(Payload::WitnessProgram {
             version: WitnessVersion::V0,
             program: pk.wpubkey_hash().ok_or(Error::UncompressedPubkey)?.to_vec(),
         })
     }
 
     /// Create a pay to script payload that embeds a witness pay to public key
-    pub fn p2shwpkh(pk: &ecdsa::PublicKey) -> Result<Payload, Error> {
+    pub fn p2shwpkh(pk: &PublicKey) -> Result<Payload, Error> {
         let builder = script::Builder::new()
             .push_int(0)
             .push_slice(&pk.wpubkey_hash().ok_or(Error::UncompressedPubkey)?);
@@ -543,7 +543,7 @@ impl Address {
     ///
     /// This is the preferred non-witness type address.
     #[inline]
-    pub fn p2pkh(pk: &ecdsa::PublicKey, network: Network) -> Address {
+    pub fn p2pkh(pk: &PublicKey, network: Network) -> Address {
         Address {
             network,
             payload: Payload::p2pkh(pk),
@@ -568,7 +568,7 @@ impl Address {
     ///
     /// # Errors
     /// Will only return an error if an uncompressed public key is provided.
-    pub fn p2wpkh(pk: &ecdsa::PublicKey, network: Network) -> Result<Address, Error> {
+    pub fn p2wpkh(pk: &PublicKey, network: Network) -> Result<Address, Error> {
         Ok(Address {
             network,
             payload: Payload::p2wpkh(pk)?,
@@ -581,7 +581,7 @@ impl Address {
     ///
     /// # Errors
     /// Will only return an Error if an uncompressed public key is provided.
-    pub fn p2shwpkh(pk: &ecdsa::PublicKey, network: Network) -> Result<Address, Error> {
+    pub fn p2shwpkh(pk: &PublicKey, network: Network) -> Result<Address, Error> {
         Ok(Address {
             network,
             payload: Payload::p2shwpkh(pk)?,
@@ -878,7 +878,7 @@ mod tests {
 
     use blockdata::script::Script;
     use network::constants::Network::{Bitcoin, Testnet};
-    use util::ecdsa::PublicKey;
+    use util::key::PublicKey;
     use secp256k1::XOnlyPublicKey;
 
     use super::*;

src/util/bip143.rs

@@ -194,7 +194,7 @@ mod tests {
     use consensus::encode::deserialize;
     use network::constants::Network;
     use util::address::Address;
-    use util::ecdsa::PublicKey;
+    use util::key::PublicKey;
     use hashes::hex::FromHex;
 
     use super::*;

src/util/bip32.rs

@@ -19,6 +19,7 @@
 
 use prelude::*;
 
+use io::Write;
 use core::{fmt, str::FromStr, default::Default};
 #[cfg(feature = "std")] use std::error;
 #[cfg(feature = "serde")] use serde;
@@ -28,9 +29,8 @@ use hashes::{sha512, Hash, HashEngine, Hmac, HmacEngine};
 use secp256k1::{self, Secp256k1, XOnlyPublicKey};
 
 use network::constants::Network;
-use util::{base58, endian};
-use util::{key, ecdsa, schnorr};
-use io::Write;
+use util::{base58, endian, key};
+use util::key::{PublicKey, PrivateKey, KeyPair};
 
 /// A chain code
 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
@@ -528,8 +528,8 @@ impl ExtendedPrivKey {
     }
 
     /// Constructs ECDSA compressed private key matching internal secret key representation.
-    pub fn to_priv(&self) -> ecdsa::PrivateKey {
-        ecdsa::PrivateKey {
+    pub fn to_priv(&self) -> PrivateKey {
+        PrivateKey {
             compressed: true,
             network: self.network,
             inner: self.private_key
@@ -538,8 +538,8 @@ impl ExtendedPrivKey {
 
     /// Constructs BIP340 keypair for Schnorr signatures and Taproot use matching the internal
     /// secret key representation.
-    pub fn to_keypair<C: secp256k1::Signing>(&self, secp: &Secp256k1<C>) -> schnorr::KeyPair {
-        schnorr::KeyPair::from_seckey_slice(secp, &self.private_key[..]).expect("BIP32 internal private key representation is broken")
+    pub fn to_keypair<C: secp256k1::Signing>(&self, secp: &Secp256k1<C>) -> KeyPair {
+        KeyPair::from_seckey_slice(secp, &self.private_key[..]).expect("BIP32 internal private key representation is broken")
     }
 
     /// Attempts to derive an extended private key from a path.
@@ -660,8 +660,8 @@ impl ExtendedPubKey {
     }
 
     /// Constructs ECDSA compressed public key matching internal public key representation.
-    pub fn to_pub(&self) -> ecdsa::PublicKey {
-        ecdsa::PublicKey {
+    pub fn to_pub(&self) -> PublicKey {
+        PublicKey {
             compressed: true,
             inner: self.public_key
         }