Merge pull request #48 from japaric/rust-crypto-no-std

no-std-ify hpke-rs-rust-crypto
cryspen · Nov 26, 2023 · 3e7e671 · 3e7e671
2 parents 65df1f4 + de6030d
commit 3e7e671
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Showing 2 changed files with 25 additions and 28 deletions.
diff --git a/rust_crypto_provider/Cargo.toml b/rust_crypto_provider/Cargo.toml
@@ -13,19 +13,20 @@ repository = "https://github.com/franziskuskiefer/hpke-rs"
 hpke-rs-crypto = { version = "0.1.3", path = "../traits" }
 # Rust crypto
 hkdf = { version = "0.12" }
-sha2 = { version = "0.10" }
-p256 = { version = "0.13", features = ["arithmetic", "ecdh"] }
-p384 = { version = "0.13" }
-x25519-dalek-ng = { version = "1.1" }
-chacha20poly1305 = { version = "0.10" }
-aes-gcm = { version = "0.10" }
+sha2 = { version = "0.10", default-features = false }
+p256 = { version = "0.13", features = ["arithmetic", "ecdh"], default-features = false }
+p384 = { version = "0.13", default-features = false }
+x25519-dalek-ng = { version = "1.1", default-features = false, features = ["u64_backend"] }
+chacha20poly1305 = { version = "0.10", default-features = false, features = ["alloc"] }
+aes-gcm = { version = "0.10", default-features = false, features = ["aes"] }
 # Randomness
-rand = { version = "0.8" }
+rand_core = { version = "0.6" }
 getrandom = { version = "0.2", features = ["js"] }
-rand_chacha = { version = "0.3" }
+rand_chacha = { version = "0.3", default-features = false }
 
 [dev-dependencies]
 criterion = { version = "0.5", features = ["html_reports"] }
+rand = { version = "0.8" }
 
 [features]
 deterministic-prng = [] # ⚠️ FOR TESTING ONLY.

diff --git a/rust_crypto_provider/src/lib.rs b/rust_crypto_provider/src/lib.rs
@@ -1,6 +1,6 @@
 #![doc = include_str!("../Readme.md")]
 
-use std::{fmt::Display, sync::RwLock};
+use core::fmt::Display;
 
 use hpke_rs_crypto::{
     error::Error,
@@ -11,7 +11,7 @@ use p256::{
     elliptic_curve::{ecdh::diffie_hellman, sec1::ToEncodedPoint},
     PublicKey, SecretKey,
 };
-use rand::SeedableRng;
+use rand_core::SeedableRng;
 use x25519_dalek_ng::{PublicKey as X25519PublicKey, StaticSecret as X25519StaticSecret};
 
 mod aead;
@@ -25,7 +25,7 @@ pub struct HpkeRustCrypto {}
 
 /// The PRNG for the Rust Crypto Provider.
 pub struct HpkeRustCryptoPrng {
-    rng: RwLock<rand_chacha::ChaCha20Rng>,
+    rng: rand_chacha::ChaCha20Rng,
     #[cfg(feature = "deterministic-prng")]
     fake_rng: Vec<u8>,
 }
@@ -107,7 +107,7 @@ impl HpkeCrypto for HpkeRustCrypto {
     }
 
     fn kem_key_gen(alg: KemAlgorithm, prng: &mut Self::HpkePrng) -> Result<Vec<u8>, Error> {
-        let mut rng = prng.rng.write().unwrap();
+        let rng = &mut prng.rng;
         match alg {
             KemAlgorithm::DhKem25519 => Ok(X25519StaticSecret::new(&mut *rng).to_bytes().to_vec()),
             KemAlgorithm::DhKemP256 => {
@@ -165,12 +165,12 @@ impl HpkeCrypto for HpkeRustCrypto {
             rand_chacha::ChaCha20Rng::from_entropy().fill_bytes(&mut fake_rng);
             HpkeRustCryptoPrng {
                 fake_rng,
-                rng: RwLock::new(rand_chacha::ChaCha20Rng::from_entropy()),
+                rng: rand_chacha::ChaCha20Rng::from_entropy(),
             }
         }
         #[cfg(not(feature = "deterministic-prng"))]
         HpkeRustCryptoPrng {
-            rng: RwLock::new(rand_chacha::ChaCha20Rng::from_entropy()),
+            rng: rand_chacha::ChaCha20Rng::from_entropy(),
         }
     }
 
@@ -200,34 +200,30 @@ impl HpkeCrypto for HpkeRustCrypto {
 
 impl RngCore for HpkeRustCryptoPrng {
     fn next_u32(&mut self) -> u32 {
-        let mut rng = self.rng.write().unwrap();
-        rng.next_u32()
+        self.rng.next_u32()
     }
 
     fn next_u64(&mut self) -> u64 {
-        let mut rng = self.rng.write().unwrap();
-        rng.next_u64()
+        self.rng.next_u64()
     }
 
     fn fill_bytes(&mut self, dest: &mut [u8]) {
-        let mut rng = self.rng.write().unwrap();
-        rng.fill_bytes(dest)
+        self.rng.fill_bytes(dest);
     }
 
-    fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), rand::Error> {
-        let mut rng = self.rng.write().unwrap();
-        rng.try_fill_bytes(dest)
+    fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), rand_core::Error> {
+        self.rng.try_fill_bytes(dest)
     }
 }
 
 impl CryptoRng for HpkeRustCryptoPrng {}
 
 impl HpkeTestRng for HpkeRustCryptoPrng {
     #[cfg(feature = "deterministic-prng")]
-    fn try_fill_test_bytes(&mut self, dest: &mut [u8]) -> Result<(), rand::Error> {
+    fn try_fill_test_bytes(&mut self, dest: &mut [u8]) -> Result<(), rand_core::Error> {
         // Here we fake our randomness for testing.
         if dest.len() > self.fake_rng.len() {
-            return Err(rand::Error::new(Error::InsufficientRandomness));
+            return Err(rand_core::Error::new(Error::InsufficientRandomness));
         }
         dest.clone_from_slice(&self.fake_rng.split_off(self.fake_rng.len() - dest.len()));
         Ok(())
@@ -238,16 +234,16 @@ impl HpkeTestRng for HpkeRustCryptoPrng {
         self.fake_rng = seed.to_vec();
     }
     #[cfg(not(feature = "deterministic-prng"))]
-    fn try_fill_test_bytes(&mut self, dest: &mut [u8]) -> Result<(), rand::Error> {
-        self.rng.write().unwrap().try_fill_bytes(dest)
+    fn try_fill_test_bytes(&mut self, dest: &mut [u8]) -> Result<(), rand_core::Error> {
+        self.rng.try_fill_bytes(dest)
     }
 
     #[cfg(not(feature = "deterministic-prng"))]
     fn seed(&mut self, _: &[u8]) {}
 }
 
 impl Display for HpkeRustCrypto {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
         write!(f, "{}", Self::name())
     }
 }