From 32d96f6c337290c2624886bd5cc30a7264c361d1 Mon Sep 17 00:00:00 2001
From: Andrew Poelstra <apoelstra@wpsoftware.net>
Date: Mon, 21 Apr 2025 22:33:28 +0000
Subject: [PATCH] bip32: make Xpriv::new_master be infallible

The only error path for this is cryptographically unreachable and was
removed in a previous commit.
---
 bitcoin/examples/bip32.rs | 2 +-
 bitcoin/src/bip32.rs      | 8 ++++----
 bitcoin/src/psbt/mod.rs   | 2 +-
 bitcoin/tests/bip_174.rs  | 2 +-
 4 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/bitcoin/examples/bip32.rs b/bitcoin/examples/bip32.rs
index 9df5ef673..6cc56697e 100644
--- a/bitcoin/examples/bip32.rs
+++ b/bitcoin/examples/bip32.rs
@@ -33,7 +33,7 @@ fn main() {
     let secp = Secp256k1::preallocated_new(buf.as_mut_slice()).unwrap();
 
     // calculate root key from seed
-    let root = Xpriv::new_master(NetworkKind::Main, &seed).unwrap();
+    let root = Xpriv::new_master(NetworkKind::Main, &seed);
     println!("Root key: {}", root);
 
     // derive child xpub
diff --git a/bitcoin/src/bip32.rs b/bitcoin/src/bip32.rs
index b1bf0bc18..b19c55c98 100644
--- a/bitcoin/src/bip32.rs
+++ b/bitcoin/src/bip32.rs
@@ -598,12 +598,12 @@ impl From<InvalidBase58PayloadLengthError> for Error {
 
 impl Xpriv {
     /// Constructs a new master key from a seed value
-    pub fn new_master(network: impl Into<NetworkKind>, seed: &[u8]) -> Result<Xpriv, Error> {
+    pub fn new_master(network: impl Into<NetworkKind>, seed: &[u8]) -> Xpriv {
         let mut engine = HmacEngine::<sha512::HashEngine>::new(b"Bitcoin seed");
         engine.input(seed);
         let hmac = engine.finalize();
 
-        Ok(Xpriv {
+        Xpriv {
             network: network.into(),
             depth: 0,
             parent_fingerprint: Default::default(),
@@ -613,7 +613,7 @@ impl Xpriv {
             )
             .expect("cryptographically unreachable"),
             chain_code: ChainCode::from_hmac(hmac),
-        })
+        }
     }
 
     /// Constructs a new ECDSA compressed private key matching internal secret key representation.
@@ -1111,7 +1111,7 @@ mod tests {
         expected_sk: &str,
         expected_pk: &str,
     ) {
-        let mut sk = Xpriv::new_master(network, seed).unwrap();
+        let mut sk = Xpriv::new_master(network, seed);
         let mut pk = Xpub::from_xpriv(secp, &sk);
 
         // Check derivation convenience method for Xpriv
diff --git a/bitcoin/src/psbt/mod.rs b/bitcoin/src/psbt/mod.rs
index 6f0ce3fc4..d648dfac3 100644
--- a/bitcoin/src/psbt/mod.rs
+++ b/bitcoin/src/psbt/mod.rs
@@ -1439,7 +1439,7 @@ mod tests {
 
         let mut hd_keypaths: BTreeMap<secp256k1::PublicKey, KeySource> = Default::default();
 
-        let mut sk: Xpriv = Xpriv::new_master(NetworkKind::Main, &seed).unwrap();
+        let mut sk: Xpriv = Xpriv::new_master(NetworkKind::Main, &seed);
 
         let fprint = sk.fingerprint(secp);
 
diff --git a/bitcoin/tests/bip_174.rs b/bitcoin/tests/bip_174.rs
index 495658658..c9ecef166 100644
--- a/bitcoin/tests/bip_174.rs
+++ b/bitcoin/tests/bip_174.rs
@@ -120,7 +120,7 @@ fn build_extended_private_key() -> Xpriv {
     let xpriv = extended_private_key.parse::<Xpriv>().unwrap();
 
     let sk = PrivateKey::from_wif(seed).unwrap();
-    let seeded = Xpriv::new_master(NetworkKind::Test, &sk.inner.secret_bytes()).unwrap();
+    let seeded = Xpriv::new_master(NetworkKind::Test, &sk.inner.secret_bytes());
     assert_eq!(xpriv, seeded);
 
     xpriv