Switch noise from the RingResolver to the DefaultResolver (#1439)

* hmm...

* Switch snow resolver to default

* Fix documentation

* Use the sha2 crate for sha512 hashing

* Use ring on native

* Use different features on different targets

Co-authored-by: Pierre Krieger <pierre.krieger1708@gmail.com>

Cargo.toml

@@ -34,6 +34,7 @@ libp2p-swarm = { version = "0.5.0", path = "swarm" }
 libp2p-uds = { version = "0.15.0", path = "transports/uds" }
 libp2p-wasm-ext = { version = "0.8.0", path = "transports/wasm-ext" }
 libp2p-yamux = { version = "0.15.0", path = "muxers/yamux" }
+libp2p-noise = { version = "0.13.0", path = "protocols/noise" }
 parking_lot = "0.10.0"
 pin-project = "0.4.6"
 smallvec = "1.0"
@@ -43,7 +44,6 @@ wasm-timer = "0.2.4"
 libp2p-deflate = { version = "0.7.0", path = "protocols/deflate" }
 libp2p-dns = { version = "0.15.0", path = "transports/dns" }
 libp2p-mdns = { version = "0.15.0", path = "misc/mdns" }
-libp2p-noise = { version = "0.13.0", path = "protocols/noise" }
 libp2p-tcp = { version = "0.15.0", path = "transports/tcp" }
 libp2p-websocket = { version = "0.15.0", path = "transports/websocket", optional = true }
 

protocols/noise/Cargo.toml

@@ -15,11 +15,17 @@ libp2p-core = { version = "0.15.0", path = "../../core" }
 log = "0.4"
 prost = "0.6.1"
 rand = "0.7.2"
-ring = { version = "0.16.9", features = ["alloc"], default-features = false }
+sha2 = "0.8.0"
-snow = { version = "0.6.1", features = ["ring-resolver"], default-features = false }
 x25519-dalek = "0.5"
 zeroize = "1"
 
+[target.'cfg(not(target_os = "unknown"))'.dependencies]
+snow = { version = "0.6.1", features = ["ring-resolver"], default-features = false }
+
+[target.'cfg(target_os = "unknown")'.dependencies]
+snow = { version = "0.6.1", features = ["default-resolver"], default-features = false }
+
+
 [dev-dependencies]
 env_logger = "0.7.1"
 libp2p-tcp = { version = "0.15.0", path = "../../transports/tcp" }

protocols/noise/src/protocol.rs

@@ -198,12 +198,10 @@ impl<T: AsRef<[u8]>> AsRef<[u8]> for PublicKey<T> {
     }
 }
 
-/// Custom `snow::CryptoResolver` which delegates to the `RingResolver`
+/// Custom `snow::CryptoResolver` which delegates to either the
+/// `RingResolver` on native or the `DefaultResolver` on wasm
 /// for hash functions and symmetric ciphers, while using x25519-dalek
-/// for Curve25519 DH. We do not use the default resolver for any of
+/// for Curve25519 DH.
-/// the choices, because it comes with unwanted additional dependencies,
-/// notably rust-crypto, and to avoid being affected by changes to
-/// the defaults.
 struct Resolver;
 
 impl snow::resolvers::CryptoResolver for Resolver {
@@ -220,12 +218,26 @@ impl snow::resolvers::CryptoResolver for Resolver {
     }
 
     fn resolve_hash(&self, choice: &snow::params::HashChoice) -> Option<Box<dyn snow::types::Hash>> {
+        #[cfg(target_os = "unknown")]
+        {
+            snow::resolvers::DefaultResolver.resolve_hash(choice)
+        }
+        #[cfg(not(target_os = "unknown"))]
+        {
             snow::resolvers::RingResolver.resolve_hash(choice)
         }
+    }
 
     fn resolve_cipher(&self, choice: &snow::params::CipherChoice) -> Option<Box<dyn snow::types::Cipher>> {
+        #[cfg(target_os = "unknown")]
+        {
+            snow::resolvers::DefaultResolver.resolve_cipher(choice)
+        }
+        #[cfg(not(target_os = "unknown"))]
+        {
             snow::resolvers::RingResolver.resolve_cipher(choice)
         }
+    }
 }
 
 /// Wrapper around a CSPRNG to implement `snow::Random` trait for.

protocols/noise/src/protocol/x25519.rs

@@ -26,7 +26,7 @@ use lazy_static::lazy_static;
 use libp2p_core::UpgradeInfo;
 use libp2p_core::{identity, identity::ed25519};
 use rand::Rng;
-use ring::digest::{SHA512, digest};
+use sha2::{Sha512, Digest};
 use x25519_dalek::{X25519_BASEPOINT_BYTES, x25519};
 use zeroize::Zeroize;
 
@@ -212,7 +212,7 @@ impl SecretKey<X25519> {
         // the same to yield a Curve25519 keypair with the same public key.
         // let ed25519_sk = ed25519::SecretKey::from(ed);
         let mut curve25519_sk: [u8; 32] = [0; 32];
-        let hash = digest(&SHA512, ed25519_sk.as_ref());
+        let hash = Sha512::digest(ed25519_sk.as_ref());
         curve25519_sk.copy_from_slice(&hash.as_ref()[..32]);
         let sk = SecretKey(X25519(curve25519_sk)); // Copy
         curve25519_sk.zeroize();

src/lib.rs

@@ -181,7 +181,6 @@ pub use libp2p_mplex as mplex;
 #[cfg(not(any(target_os = "emscripten", target_os = "unknown")))]
 #[doc(inline)]
 pub use libp2p_mdns as mdns;
-#[cfg(not(any(target_os = "emscripten", target_os = "unknown")))]
 #[doc(inline)]
 pub use libp2p_noise as noise;
 #[doc(inline)]