From 06fae85e6709056a85ea143461e457e7aa0fd233 Mon Sep 17 00:00:00 2001
From: Lorenz Leutgeb <lorenz.leutgeb@radicle.xyz>
Date: Fri, 13 Mar 2026 14:18:46 +0100
Subject: [PATCH] crypto: `impl Signer` based on `Keypair`

Since all signers implement `signature::Keypair`, we can simplify the
implementations of `signature::Signer<ExtendedSignature>`. A blanket
implementation is not possible, because we do not control
`signature::Signer`.
---
 crates/radicle-crypto/Cargo.toml          | 2 +-
 crates/radicle-crypto/src/ssh/agent.rs    | 5 +++--
 crates/radicle-crypto/src/ssh/keystore.rs | 5 +++--
 crates/radicle-crypto/src/test/signer.rs  | 5 +++--
 4 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/crates/radicle-crypto/Cargo.toml b/crates/radicle-crypto/Cargo.toml
index b9d0a1d3..d18d61db 100644
--- a/crates/radicle-crypto/Cargo.toml
+++ b/crates/radicle-crypto/Cargo.toml
@@ -27,7 +27,7 @@ git-ref-format-core = { workspace = true, optional = true }
 radicle-ssh = { workspace = true, optional = true }
 schemars = { workspace = true, optional = true, features = ["derive", "std"] }
 serde = { workspace = true, features = ["derive", "std"] }
-signature = { workspace = true }
+signature = { workspace = true, features = ["std"] }
 sqlite = { workspace = true, features = ["bundled"], optional = true }
 ssh-key = { version = "0.6.3", default-features = false, features = ["std", "encryption", "getrandom"], optional = true }
 thiserror = { workspace = true, default-features = true }
diff --git a/crates/radicle-crypto/src/ssh/agent.rs b/crates/radicle-crypto/src/ssh/agent.rs
index ab73fa37..901b0e62 100644
--- a/crates/radicle-crypto/src/ssh/agent.rs
+++ b/crates/radicle-crypto/src/ssh/agent.rs
@@ -65,9 +65,10 @@ impl signature::Signer<Signature> for AgentSigner {
 
 impl signature::Signer<ExtendedSignature> for AgentSigner {
     fn try_sign(&self, msg: &[u8]) -> Result<ExtendedSignature, signature::Error> {
+        use signature::Keypair as _;
         Ok(ExtendedSignature {
-            key: self.public,
-            sig: Signer::try_sign(self, msg).map_err(signature::Error::from_source)?,
+            key: self.verifying_key(),
+            sig: self.try_sign(msg)?,
         })
     }
 }
diff --git a/crates/radicle-crypto/src/ssh/keystore.rs b/crates/radicle-crypto/src/ssh/keystore.rs
index 84ab0d6f..5f768647 100644
--- a/crates/radicle-crypto/src/ssh/keystore.rs
+++ b/crates/radicle-crypto/src/ssh/keystore.rs
@@ -258,9 +258,10 @@ impl signature::Signer<Signature> for MemorySigner {
 
 impl signature::Signer<ExtendedSignature> for MemorySigner {
     fn try_sign(&self, msg: &[u8]) -> Result<ExtendedSignature, signature::Error> {
+        use signature::Keypair as _;
         Ok(ExtendedSignature {
-            key: self.public,
-            sig: Signer::sign(self, msg),
+            key: self.verifying_key(),
+            sig: self.try_sign(msg)?,
         })
     }
 }
diff --git a/crates/radicle-crypto/src/test/signer.rs b/crates/radicle-crypto/src/test/signer.rs
index 6881699a..dd036340 100644
--- a/crates/radicle-crypto/src/test/signer.rs
+++ b/crates/radicle-crypto/src/test/signer.rs
@@ -10,9 +10,10 @@ pub struct MockSigner {
 
 impl signature::Signer<ExtendedSignature> for MockSigner {
     fn try_sign(&self, msg: &[u8]) -> Result<ExtendedSignature, signature::Error> {
+        use signature::Keypair as _;
         Ok(ExtendedSignature {
-            key: self.pk,
-            sig: signature::Signer::<Signature>::try_sign(self, msg)?,
+            key: self.verifying_key(),
+            sig: self.try_sign(msg)?,
         })
     }
 }