Transition remaining items to no-std

penumbra-zone · Feb 13, 2024 · c849ea1 · c849ea1
1 parent 606d02d
commit c849ea1
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Showing 4 changed files with 86 additions and 76 deletions.
diff --git a/Cargo.toml b/Cargo.toml
@@ -11,8 +11,7 @@ repository = "https://github.com/penumbra-zone/decaf377-rdsa"
 [dependencies]
 # No Alloc, No Std
 blake2b_simd = { version = "0.5", default-features = false }
-cfg-if = "1.0"
-decaf377 = { git = "https://github.com/penumbra-zone/decaf377", rev = "f8c185eb40d2ece19783ce02b99861e85d304e92", default-features = false }
+decaf377 = { git = "https://github.com/penumbra-zone/decaf377", rev = "e26c88c896d9e3da4677bfe9ba127ce45979e0b2", default-features = false }
 digest = { version = "0.9", default-features = false }
 rand_core = { version = "0.6", default-features = false }
 hex = { version = "0.4", default-features = false }
@@ -39,8 +38,7 @@ name = "bench"
 harness = false
 
 [features]
-#default = ["serde", "std"]
-default = []
+default = ["serde", "std"]
 alloc = ["ark-ff", "ark-serialize"]
 std = ["alloc", "ark-ff/std", "blake2b_simd/std", "decaf377/arkworks", "digest/std", "hex/std", "rand_core/std", "thiserror"]
 parallel = ["ark-ff/parallel", "decaf377/parallel"]

diff --git a/src/lib.rs b/src/lib.rs
@@ -1,27 +1,22 @@
 #![cfg_attr(not(feature = "std"), no_std)]
 #![doc = include_str!("../README.md")]
-use cfg_if::cfg_if;
 
 mod domain;
 mod error;
 mod hash;
 use hash::HStar;
 mod signature;
 
+mod signing_key;
+mod verification_key;
+
 pub use domain::{Binding, Domain, SpendAuth};
 pub use error::Error;
+pub use signature::Signature;
+pub use signing_key::SigningKey;
+pub use verification_key::{VerificationKey, VerificationKeyBytes};
 
-cfg_if! {
-    if #[cfg(feature = "std")] {
-        pub mod batch;
-
-        mod signing_key;
-        mod verification_key;
-
-        pub use signature::Signature;
-        pub use signing_key::SigningKey;
-        pub use verification_key::{VerificationKey, VerificationKeyBytes};
+pub use decaf377::Fr;
 
-        pub use decaf377::Fr;
-    }
-}
+#[cfg(feature = "std")]
+pub mod batch;
diff --git a/src/signing_key.rs b/src/signing_key.rs
@@ -1,9 +1,7 @@
-use std::convert::{TryFrom, TryInto};
-
 use decaf377::Fr;
 use rand_core::{CryptoRng, RngCore};
 
-use crate::{Binding, Domain, Error, Signature, SpendAuth, VerificationKey};
+use crate::{Domain, Error, Signature, SpendAuth, VerificationKey};
 
 /// A `decaf377-rdsa` signing key.
 #[derive(Copy, Clone)]
@@ -16,22 +14,6 @@ pub struct SigningKey<D: Domain> {
     pk: VerificationKey<D>,
 }
 
-impl std::fmt::Debug for SigningKey<Binding> {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        f.debug_tuple("SigningKey<Binding>")
-            .field(&hex::encode(&<[u8; 32]>::from(*self)))
-            .finish()
-    }
-}
-
-impl std::fmt::Debug for SigningKey<SpendAuth> {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        f.debug_tuple("SigningKey<SpendAuth>")
-            .field(&hex::encode(&<[u8; 32]>::from(*self)))
-            .finish()
-    }
-}
-
 impl<'a, D: Domain> From<&'a SigningKey<D>> for VerificationKey<D> {
     fn from(sk: &'a SigningKey<D>) -> VerificationKey<D> {
         sk.pk.clone()
@@ -63,8 +45,7 @@ impl<D: Domain> TryFrom<[u8; 32]> for SigningKey<D> {
     type Error = Error;
 
     fn try_from(bytes: [u8; 32]) -> Result<Self, Self::Error> {
-        use ark_serialize::CanonicalDeserialize;
-        let sk = Fr::deserialize_compressed(&bytes[..]).map_err(|_| Error::MalformedSigningKey)?;
+        let sk = Fr::from_bytes_checked(&bytes).map_err(|_| Error::MalformedSigningKey)?;
         Ok(Self::new_from_field(sk))
     }
 }
@@ -186,3 +167,30 @@ impl<D: Domain> SigningKey<D> {
         Signature::from_parts(r_bytes, s_bytes)
     }
 }
+
+#[cfg(feature = "std")]
+mod std_only {
+    use super::*;
+    use std::fmt;
+
+    use crate::Binding;
+
+    impl fmt::Debug for SigningKey<Binding> {
+        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+            f.debug_tuple("SigningKey<Binding>")
+                .field(&hex::encode(&<[u8; 32]>::from(*self)))
+                .finish()
+        }
+    }
+
+    impl fmt::Debug for SigningKey<SpendAuth> {
+        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+            f.debug_tuple("SigningKey<SpendAuth>")
+                .field(&hex::encode(&<[u8; 32]>::from(*self)))
+                .finish()
+        }
+    }
+}
+
+#[cfg(feature = "std")]
+pub use std_only::*;
diff --git a/src/verification_key.rs b/src/verification_key.rs
@@ -1,13 +1,12 @@
-use std::{
-    cmp::Ord,
-    convert::TryFrom,
+use core::{
+    cmp::{self, Ord},
     hash::{Hash, Hasher},
     marker::PhantomData,
 };
 
 use decaf377::Fr;
 
-use crate::{domain::Sealed, Binding, Domain, Error, Signature, SpendAuth};
+use crate::{domain::Sealed, Domain, Error, Signature, SpendAuth};
 
 /// A refinement type for `[u8; 32]` indicating that the bytes represent
 /// an encoding of a `decaf377-rdsa` verification key.
@@ -51,13 +50,13 @@ impl<D: Domain> Hash for VerificationKeyBytes<D> {
 }
 
 impl<D: Domain> PartialOrd for VerificationKeyBytes<D> {
-    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+    fn partial_cmp(&self, other: &Self) -> Option<cmp::Ordering> {
         self.bytes.partial_cmp(&other.bytes)
     }
 }
 
 impl<D: Domain> Ord for VerificationKeyBytes<D> {
-    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
+    fn cmp(&self, other: &Self) -> cmp::Ordering {
         self.bytes.cmp(&other.bytes)
     }
 }
@@ -84,13 +83,13 @@ impl<D: Domain> Hash for VerificationKey<D> {
 }
 
 impl<D: Domain> PartialOrd for VerificationKey<D> {
-    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+    fn partial_cmp(&self, other: &Self) -> Option<cmp::Ordering> {
         self.bytes.partial_cmp(&other.bytes)
     }
 }
 
 impl<D: Domain> Ord for VerificationKey<D> {
-    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
+    fn cmp(&self, other: &Self) -> cmp::Ordering {
         self.bytes.cmp(&other.bytes)
     }
 }
@@ -212,7 +211,7 @@ impl<D: Domain> VerificationKey<D> {
 
     /// Convenience method for identity checks.
     pub fn is_identity(&self) -> bool {
-        self.point.is_identity()
+        self.point == decaf377::Element::IDENTITY
     }
 
     /// Verify a purported `signature` with a prehashed challenge.
@@ -232,57 +231,67 @@ impl<D: Domain> VerificationKey<D> {
         let cA = self.point * c;
         let check = sB - cA - R;
 
-        if check.is_identity() {
+        if check == decaf377::Element::IDENTITY {
             Ok(())
         } else {
             Err(Error::InvalidSignature)
         }
     }
 }
 
-impl<D: Domain> std::cmp::PartialEq for VerificationKey<D> {
+impl<D: Domain> PartialEq for VerificationKey<D> {
     fn eq(&self, other: &Self) -> bool {
         self.bytes.eq(&other.bytes)
     }
 }
 
-impl<D: Domain> std::cmp::PartialEq for VerificationKeyBytes<D> {
+impl<D: Domain> PartialEq for VerificationKeyBytes<D> {
     fn eq(&self, other: &Self) -> bool {
         self.bytes.eq(&other.bytes)
     }
 }
 
-impl<D: Domain> std::cmp::Eq for VerificationKey<D> {}
-impl<D: Domain> std::cmp::Eq for VerificationKeyBytes<D> {}
+impl<D: Domain> Eq for VerificationKey<D> {}
+impl<D: Domain> Eq for VerificationKeyBytes<D> {}
 
-impl std::fmt::Debug for VerificationKey<Binding> {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        f.debug_tuple("VerificationKey<Binding>")
-            .field(&hex::encode(&<[u8; 32]>::from(*self)))
-            .finish()
+#[cfg(feature = "std")]
+mod std_only {
+    use super::*;
+
+    use crate::Binding;
+
+    impl std::fmt::Debug for VerificationKey<Binding> {
+        fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+            f.debug_tuple("VerificationKey<Binding>")
+                .field(&hex::encode(&<[u8; 32]>::from(*self)))
+                .finish()
+        }
     }
-}
 
-impl std::fmt::Debug for VerificationKey<SpendAuth> {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        f.debug_tuple("VerificationKey<SpendAuth>")
-            .field(&hex::encode(&<[u8; 32]>::from(*self)))
-            .finish()
+    impl std::fmt::Debug for VerificationKey<SpendAuth> {
+        fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+            f.debug_tuple("VerificationKey<SpendAuth>")
+                .field(&hex::encode(&<[u8; 32]>::from(*self)))
+                .finish()
+        }
     }
-}
 
-impl std::fmt::Debug for VerificationKeyBytes<Binding> {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        f.debug_tuple("VerificationKeyBytes<Binding>")
-            .field(&hex::encode(&<[u8; 32]>::from(*self)))
-            .finish()
+    impl std::fmt::Debug for VerificationKeyBytes<Binding> {
+        fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+            f.debug_tuple("VerificationKeyBytes<Binding>")
+                .field(&hex::encode(&<[u8; 32]>::from(*self)))
+                .finish()
+        }
     }
-}
 
-impl std::fmt::Debug for VerificationKeyBytes<SpendAuth> {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        f.debug_tuple("VerificationKeyBytes<SpendAuth>")
-            .field(&hex::encode(&<[u8; 32]>::from(*self)))
-            .finish()
+    impl std::fmt::Debug for VerificationKeyBytes<SpendAuth> {
+        fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+            f.debug_tuple("VerificationKeyBytes<SpendAuth>")
+                .field(&hex::encode(&<[u8; 32]>::from(*self)))
+                .finish()
+        }
     }
 }
+
+#[cfg(feature = "std")]
+pub use std_only::*;