From 1950f10578e9ce760e739d036aefcb558ad40345 Mon Sep 17 00:00:00 2001
From: nullPointerEnjoyer <dev1@mintlayer.org>
Date: Sat, 17 Oct 2026 18:16:43 +0200
Subject: [PATCH 1/2] fix(crypto): keep vrf private key material out of debug
 output

---
 crypto/src/vrf/mod.rs            | 33 ++++++++++++++++++++++++++++++--
 crypto/src/vrf/schnorrkel/mod.rs | 25 +++++++++++++++++++++++-
 2 files changed, 55 insertions(+), 3 deletions(-)

diff --git a/crypto/src/vrf/mod.rs b/crypto/src/vrf/mod.rs
index 4de87f2fcc..2c14efd440 100644
--- a/crypto/src/vrf/mod.rs
+++ b/crypto/src/vrf/mod.rs
@@ -55,17 +55,31 @@ pub enum VRFKeyKind {
 }
 
 #[must_use]
-#[derive(Debug, PartialEq, Eq, Clone, Decode, Encode)]
+#[derive(PartialEq, Eq, Clone, Decode, Encode)]
 pub struct VRFPrivateKey {
     key: VRFPrivateKeyHolder,
 }
 
-#[derive(Debug, PartialEq, Eq, Clone, Decode, Encode)]
+impl std::fmt::Debug for VRFPrivateKey {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        // Keep the key material out of the formatted output; this type can end up in
+        // log lines through derived Debug impls of larger structures.
+        f.write_str("VRFPrivateKey(<redacted>)")
+    }
+}
+
+#[derive(PartialEq, Eq, Clone, Decode, Encode)]
 pub(crate) enum VRFPrivateKeyHolder {
     #[codec(index = 0)]
     Schnorrkel(SchnorrkelPrivateKey),
 }
 
+impl std::fmt::Debug for VRFPrivateKeyHolder {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.write_str("VRFPrivateKeyHolder(<redacted>)")
+    }
+}
+
 #[must_use]
 #[derive(Debug, PartialOrd, Ord, PartialEq, Eq, Clone, Decode, Encode)]
 pub struct VRFPublicKey {
@@ -348,6 +362,21 @@ mod tests {
 
     use super::*;
 
+    #[test]
+    fn private_key_debug_hides_key_material() {
+        let mut rng = make_seedable_rng(Seed::from_entropy());
+        let (sk, _pk) = VRFPrivateKey::new_from_rng(&mut rng, VRFKeyKind::Schnorrkel);
+
+        let encoded_sk = sk.encode();
+        let debug_output = format!("{sk:?}");
+
+        assert!(debug_output.contains("<redacted>"));
+        // No byte of the encoded secret may appear anywhere in the formatted output.
+        for byte in &encoded_sk {
+            assert!(!debug_output.contains(&byte.to_string()));
+        }
+    }
+
     #[rstest]
     #[trace]
     #[case(Seed::from_entropy())]
diff --git a/crypto/src/vrf/schnorrkel/mod.rs b/crypto/src/vrf/schnorrkel/mod.rs
index c7f13ba6ed..9483881b00 100644
--- a/crypto/src/vrf/schnorrkel/mod.rs
+++ b/crypto/src/vrf/schnorrkel/mod.rs
@@ -115,12 +115,20 @@ impl Decode for SchnorrkelPublicKey {
     }
 }
 
-#[derive(Debug, Clone, PartialEq, Eq)]
+#[derive(Clone, PartialEq, Eq)]
 #[must_use]
 pub struct SchnorrkelPrivateKey {
     key: schnorrkel::SecretKey,
 }
 
+impl std::fmt::Debug for SchnorrkelPrivateKey {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        // Keep the key material out of the formatted output; this type can end up in
+        // log lines through derived Debug impls of larger structures.
+        f.write_str("SchnorrkelPrivateKey(<redacted>)")
+    }
+}
+
 impl SchnorrkelPrivateKey {
     pub fn new<R: CryptoRng>(rng: &mut R) -> (SchnorrkelPrivateKey, SchnorrkelPublicKey) {
         let sk = schnorrkel::SecretKey::generate_with(&mut Rng08Adapter(rng));
@@ -221,6 +229,21 @@ mod tests {
     use serialization::{DecodeAll, Encode};
     use test_utils::random::{Seed, make_seedable_rng};
 
+    #[test]
+    fn private_key_debug_hides_key_material() {
+        let mut rng = make_true_rng();
+        let (sk, _pk) = SchnorrkelPrivateKey::new(&mut rng);
+
+        let encoded_sk = sk.encode();
+        let debug_output = format!("{sk:?}");
+
+        assert!(debug_output.contains("<redacted>"));
+        // No byte of the encoded secret may appear anywhere in the formatted output.
+        for byte in &encoded_sk {
+            assert!(!debug_output.contains(&byte.to_string()));
+        }
+    }
+
     #[test]
     fn key_serialization() {
         let mut rng = make_true_rng();

From 2ebfedfb74ecc11881443083f0aa4e5d018e232a Mon Sep 17 00:00:00 2001
From: nullPointerEnjoyer <dev1@mintlayer.org>
Date: Sat, 17 Oct 2026 18:22:10 +0200
Subject: [PATCH 2/2] test(crypto): pin the redacted vrf debug rendering
 exactly

---
 crypto/src/vrf/mod.rs            | 9 +--------
 crypto/src/vrf/schnorrkel/mod.rs | 9 +--------
 2 files changed, 2 insertions(+), 16 deletions(-)

diff --git a/crypto/src/vrf/mod.rs b/crypto/src/vrf/mod.rs
index 2c14efd440..dec529b652 100644
--- a/crypto/src/vrf/mod.rs
+++ b/crypto/src/vrf/mod.rs
@@ -367,14 +367,7 @@ mod tests {
         let mut rng = make_seedable_rng(Seed::from_entropy());
         let (sk, _pk) = VRFPrivateKey::new_from_rng(&mut rng, VRFKeyKind::Schnorrkel);
 
-        let encoded_sk = sk.encode();
-        let debug_output = format!("{sk:?}");
-
-        assert!(debug_output.contains("<redacted>"));
-        // No byte of the encoded secret may appear anywhere in the formatted output.
-        for byte in &encoded_sk {
-            assert!(!debug_output.contains(&byte.to_string()));
-        }
+        assert_eq!(format!("{sk:?}"), "VRFPrivateKey(<redacted>)");
     }
 
     #[rstest]
diff --git a/crypto/src/vrf/schnorrkel/mod.rs b/crypto/src/vrf/schnorrkel/mod.rs
index 9483881b00..8ae635c62b 100644
--- a/crypto/src/vrf/schnorrkel/mod.rs
+++ b/crypto/src/vrf/schnorrkel/mod.rs
@@ -234,14 +234,7 @@ mod tests {
         let mut rng = make_true_rng();
         let (sk, _pk) = SchnorrkelPrivateKey::new(&mut rng);
 
-        let encoded_sk = sk.encode();
-        let debug_output = format!("{sk:?}");
-
-        assert!(debug_output.contains("<redacted>"));
-        // No byte of the encoded secret may appear anywhere in the formatted output.
-        for byte in &encoded_sk {
-            assert!(!debug_output.contains(&byte.to_string()));
-        }
+        assert_eq!(format!("{sk:?}"), "SchnorrkelPrivateKey(<redacted>)");
     }
 
     #[test]