Differentiate no-std from alloc within tests/no-std

Fixes `no-std` builds for packages which intended to be `no-std` (without
`alloc`).

Updates a variety of MSRVs to 1.73 due to `flexible-transcript` no longer using
`std-shims` to achieve 1.66 (as `std-shims` requires `alloc`). A future
improvement would be for `std-shims` to have an `alloc` feature and only
provide MSRV shims without it.

crypto/ciphersuite/Cargo.toml

@@ -7,7 +7,7 @@ repository = "https://github.com/serai-dex/serai/tree/develop/crypto/ciphersuite
 authors = ["Luke Parker <lukeparker5132@gmail.com>"]
 keywords = ["ciphersuite", "ff", "group"]
 edition = "2021"
-rust-version = "1.66"
+rust-version = "1.73"
 
 [package.metadata.docs.rs]
 all-features = true

crypto/dalek-ff-group/Cargo.toml

@@ -7,7 +7,7 @@ repository = "https://github.com/serai-dex/serai/tree/develop/crypto/dalek-ff-gr
 authors = ["Luke Parker <lukeparker5132@gmail.com>"]
 keywords = ["curve25519", "ed25519", "ristretto", "dalek", "group"]
 edition = "2021"
-rust-version = "1.66"
+rust-version = "1.73"
 
 [package.metadata.docs.rs]
 all-features = true
@@ -33,7 +33,7 @@ ciphersuite = { path = "../ciphersuite", default-features = false }
 
 crypto-bigint = { version = "0.5", default-features = false, features = ["zeroize"] }
 
-curve25519-dalek = { version = ">= 4.0, < 4.2", default-features = false, features = ["alloc", "zeroize", "digest", "group", "precomputed-tables"] }
+curve25519-dalek = { version = ">= 4.0, < 4.2", default-features = false, features = ["zeroize", "digest", "group", "precomputed-tables"] }
 
 [dev-dependencies]
 hex = "0.4"
@@ -41,6 +41,6 @@ rand_core = { version = "0.6", default-features = false, features = ["std"] }
 ff-group-tests = { path = "../ff-group-tests" }
 
 [features]
-alloc = ["zeroize/alloc", "ciphersuite/alloc"]
+alloc = ["zeroize/alloc", "ciphersuite/alloc", "curve25519-dalek/alloc"]
 std = ["alloc", "zeroize/std", "subtle/std", "rand_core/std", "digest/std", "sha2/std", "ciphersuite/std"]
 default = ["std"]

crypto/dalek-ff-group/src/ciphersuite.rs

@@ -29,7 +29,10 @@ macro_rules! dalek_curve {
       }
 
       fn hash_to_F(dst: &[u8], data: &[u8]) -> Self::F {
-        Scalar::from_hash(Sha512::new_with_prefix(&[dst, data].concat()))
+        let mut digest = Sha512::new();
+        digest.update(dst);
+        digest.update(data);
+        Scalar::from_hash(digest)
       }
     }
   };

crypto/dkg/Cargo.toml

@@ -7,7 +7,7 @@ repository = "https://github.com/serai-dex/serai/tree/develop/crypto/dkg"
 authors = ["Luke Parker <lukeparker5132@gmail.com>"]
 keywords = ["dkg", "multisig", "threshold", "ff", "group"]
 edition = "2021"
-rust-version = "1.66"
+rust-version = "1.73"
 
 [package.metadata.docs.rs]
 all-features = true

crypto/dkg/dealer/Cargo.toml

@@ -7,7 +7,7 @@ repository = "https://github.com/serai-dex/serai/tree/develop/crypto/dkg/dealer"
 authors = ["Luke Parker <lukeparker5132@gmail.com>"]
 keywords = ["dkg", "multisig", "threshold", "ff", "group"]
 edition = "2021"
-rust-version = "1.66"
+rust-version = "1.73"
 
 [package.metadata.docs.rs]
 all-features = true

crypto/dkg/recovery/Cargo.toml

@@ -7,7 +7,7 @@ repository = "https://github.com/serai-dex/serai/tree/develop/crypto/dkg/recover
 authors = ["Luke Parker <lukeparker5132@gmail.com>"]
 keywords = ["dkg", "multisig", "threshold", "ff", "group"]
 edition = "2021"
-rust-version = "1.66"
+rust-version = "1.73"
 
 [package.metadata.docs.rs]
 all-features = true

crypto/ed448/src/ciphersuite.rs

@@ -71,7 +71,11 @@ impl Ciphersuite for Ed448 {
   }
 
   fn hash_to_F(dst: &[u8], data: &[u8]) -> Self::F {
-    let digest = Self::H::digest([dst, data].concat());
+    let mut digest = Self::H::new();
+    Update::update(&mut digest, dst);
+    Update::update(&mut digest, data);
+    let digest = digest.finalize();
+
     let mut wide_scalar = [0; 114];
     wide_scalar.copy_from_slice(digest.as_ref());
     Scalar::from_uniform_bytes(&wide_scalar)

crypto/embedwards25519/src/lib.rs

@@ -94,9 +94,10 @@ impl ciphersuite::Ciphersuite for Embedwards25519 {
   /// substrings of each other.
   fn hash_to_F(dst: &[u8], data: &[u8]) -> Self::F {
     use blake2::Digest;
-    <Scalar as FromUniformBytes<64>>::from_uniform_bytes(
-      &Self::H::digest([dst, data].concat()).into(),
-    )
+    let mut digest = Self::H::new();
+    digest.update(dst);
+    digest.update(data);
+    <Scalar as FromUniformBytes<64>>::from_uniform_bytes(&digest.finalize().into())
   }
 
   // We override the provided impl, which compares against the reserialization, because

crypto/secq256k1/src/lib.rs

@@ -127,9 +127,10 @@ impl ciphersuite::Ciphersuite for Secq256k1 {
   /// substrings of each other.
   fn hash_to_F(dst: &[u8], data: &[u8]) -> Self::F {
     use blake2::Digest;
-    <Scalar as FromUniformBytes<64>>::from_uniform_bytes(
-      &Self::H::digest([dst, data].concat()).into(),
-    )
+    let mut digest = Self::H::new();
+    digest.update(dst);
+    digest.update(data);
+    <Scalar as FromUniformBytes<64>>::from_uniform_bytes(&digest.finalize().into())
   }
 
   // We override the provided impl, which compares against the reserialization, because

crypto/transcript/Cargo.toml

@@ -7,7 +7,7 @@ repository = "https://github.com/serai-dex/serai/tree/develop/crypto/transcript"
 authors = ["Luke Parker <lukeparker5132@gmail.com>"]
 keywords = ["transcript"]
 edition = "2021"
-rust-version = "1.66"
+rust-version = "1.73"
 
 [package.metadata.docs.rs]
 all-features = true
@@ -17,8 +17,6 @@ rustdoc-args = ["--cfg", "docsrs"]
 workspace = true
 
 [dependencies]
-std-shims = { path = "../../common/std-shims", version = "0.1.4", default-features = false }
-
 zeroize = { version = "^1.5", default-features = false }
 
 digest = { version = "0.10", default-features = false, features = ["core-api"] }
@@ -31,7 +29,7 @@ sha2 = { version = "0.10", default-features = false }
 blake2 = { version = "0.10", default-features = false }
 
 [features]
-std = ["std-shims/std", "zeroize/std", "digest/std", "blake2?/std", "merlin?/std"]
+std = ["zeroize/std", "digest/std", "blake2?/std", "merlin?/std"]
 recommended = ["blake2"]
 tests = []
 default = ["std"]

crypto/transcript/src/lib.rs

@@ -2,9 +2,6 @@
 #![doc = include_str!("../README.md")]
 #![no_std]
 
-#[allow(unused_imports)]
-use std_shims::prelude::*;
-
 use zeroize::Zeroize;
 
 use digest::{