Update and remove unused dependencies

crypto/frost/Cargo.toml

@@ -19,24 +19,19 @@ rand_core = "0.6"
 rand_chacha = "0.3"
 
 zeroize = { version = "^1.5", features = ["zeroize_derive"] }
-subtle = "2"
+subtle = "^2.4"
 
-hex = "0.4"
+hex = { version = "0.4", optional = true }
 
 digest = "0.10"
-
-hkdf = "0.12"
-chacha20 = { version = "0.9", features = ["zeroize"] }
+transcript = { package = "flexible-transcript", path = "../transcript", version = "0.2", features = ["recommended"] }
 
 group = "0.12"
+ciphersuite = { path = "../ciphersuite", version = "0.1", features = ["std"] }
 
 dalek-ff-group = { path = "../dalek-ff-group", version = "^0.1.2", optional = true }
 minimal-ed448 = { path = "../ed448", version = "^0.1.2", optional = true }
 
-ciphersuite = { path = "../ciphersuite", version = "0.1", features = ["std"] }
-
-transcript = { package = "flexible-transcript", path = "../transcript", version = "0.2", features = ["recommended"] }
-
 multiexp = { path = "../multiexp", version = "0.2", features = ["batch"] }
 
 schnorr = { package = "schnorr-signatures", path = "../schnorr", version = "0.2" }
@@ -58,4 +53,4 @@ p256 = ["ciphersuite/p256"]
 
 ed448 = ["minimal-ed448", "ciphersuite/ed448"]
 
-tests = ["dkg/tests"]
+tests = ["hex", "dkg/tests"]

crypto/frost/src/sign.rs

@@ -11,10 +11,7 @@ use zeroize::{Zeroize, Zeroizing};
 
 use transcript::Transcript;
 
-use group::{
-  ff::{Field, PrimeField},
-  GroupEncoding,
-};
+use group::{ff::PrimeField, GroupEncoding};
 use multiexp::BatchVerifier;
 
 use crate::{
@@ -198,6 +195,8 @@ impl<C: Curve> Writable for SignatureShare<C> {
 #[cfg(any(test, feature = "tests"))]
 impl<C: Curve> SignatureShare<C> {
   pub(crate) fn invalidate(&mut self) {
+    use group::ff::Field;
+
     self.0 += C::F::one();
   }
 }