Migrate from ring to ed25519-dalek, take 2 (#3844)

* Migrate from ring to ed25519-dalek

* Move gen_keypair_file test to a more appropriate location

* Fixup bench-exchange and add helper fn for single deterministic keypair

* Update golden

core/src/gen_keys.rs

@@ -4,7 +4,6 @@ use rand::{Rng, SeedableRng};
 use rand_chacha::ChaChaRng;
 use rayon::prelude::*;
 use solana_sdk::signature::Keypair;
-use untrusted::Input;
 
 pub struct GenKeys {
     generator: ChaChaRng,
@@ -26,10 +25,14 @@ impl GenKeys {
         (0..n).map(|_| self.gen_seed()).collect()
     }
 
+    pub fn gen_keypair(&mut self) -> Keypair {
+        Keypair::generate(&mut self.generator)
+    }
+
     pub fn gen_n_keypairs(&mut self, n: u64) -> Vec<Keypair> {
         self.gen_n_seeds(n)
             .into_par_iter()
-            .map(|seed| Keypair::from_seed_unchecked(Input::from(&seed)).unwrap())
+            .map(|seed| Keypair::generate(&mut ChaChaRng::from_seed(seed)))
             .collect()
     }
 }
@@ -52,6 +55,17 @@ mod tests {
         }
     }
 
+    #[test]
+    fn test_gen_keypair_is_deterministic() {
+        let seed = [0u8; 32];
+        let mut gen0 = GenKeys::new(seed);
+        let mut gen1 = GenKeys::new(seed);
+        assert_eq!(
+            gen0.gen_keypair().to_bytes().to_vec(),
+            gen1.gen_keypair().to_bytes().to_vec()
+        );
+    }
+
     fn gen_n_pubkeys(seed: [u8; 32], n: u64) -> HashSet<Pubkey> {
         GenKeys::new(seed)
             .gen_n_keypairs(n)