feat: simplify the verify-signatures feature (#2020)

* feat: simplify the verify-signatures feature

A new ambassador crate was released so we can now use attributes inside
delegable traits (and some macros that were previously unexported are
now exported by default). Basically, I'm just deleting code.

* chore: update changelog

Author: Stebalien

Cargo.lock

@@ -64,7 +64,7 @@ arbitrary = "1.3.0"
 itertools = "0.11.0"
 once_cell = "1.18.0"
 unsigned-varint = "0.7.2"
-ambassador = "0.3.5"
+ambassador = "0.4.0"
 
 # dev/tools/tests
 criterion = "0.5.1"

Cargo.toml

@@ -4,6 +4,8 @@ Changes to the reference FVM implementation.
 
 ## [Unreleased]
 
+- **BREAKING**: Simplify the verify-signtures feature and update ambassador. This is a minor-breaking change because the ambassador macros are now only exported from the prelude/kernel module, not the crate root as they previously were.
+
 ## 4.3.0 [2023-06-12]
 
 - feat: FIP-0079: syscall for aggregated bls verification [#2003](https://github.com/filecoin-project/ref-fvm/pull/2003)

fvm/CHANGELOG.md

@@ -220,11 +220,11 @@ pub trait ActorOps {
     fn balance_of(&self, actor_id: ActorID) -> Result<TokenAmount>;
 }
 
-#[cfg(feature = "verify-signature")]
 /// Cryptographic primitives provided by the kernel.
 #[delegatable_trait]
 pub trait CryptoOps {
     /// Verifies that a signature is valid for an address and plaintext.
+    #[cfg(feature = "verify-signature")]
     fn verify_signature(
         &self,
         sig_type: SignatureType,
@@ -263,40 +263,6 @@ pub trait CryptoOps {
     fn hash(&self, code: u64, data: &[u8]) -> Result<Multihash>;
 }
 
-#[cfg(not(feature = "verify-signature"))]
-/// Cryptographic primitives provided by the kernel.
-#[delegatable_trait]
-pub trait CryptoOps {
-    /// Verifies a BLS aggregate signature. In the case where there is one signer/signed plaintext,
-    /// this is equivalent to verifying a non-aggregated BLS signature.
-    ///
-    /// Returns:
-    /// - `Ok(true)` on a valid signature.
-    /// - `Ok(false)` on an invalid signature or if the signature or public keys' bytes represent an
-    ///    invalid curve point.
-    /// - `Err(IllegalArgument)` if `pub_keys.len() != plaintexts.len()`.
-    fn verify_bls_aggregate(
-        &self,
-        aggregate_sig: &[u8; fvm_shared::crypto::signature::BLS_SIG_LEN],
-        pub_keys: &[[u8; fvm_shared::crypto::signature::BLS_PUB_LEN]],
-        plaintexts_concat: &[u8],
-        plaintext_lens: &[u32],
-    ) -> Result<bool>;
-
-    /// Given a message hash and its signature, recovers the public key of the signer.
-    fn recover_secp_public_key(
-        &self,
-        hash: &[u8; SECP_SIG_MESSAGE_HASH_SIZE],
-        signature: &[u8; SECP_SIG_LEN],
-    ) -> Result<[u8; SECP_PUB_LEN]>;
-
-    /// Hashes input `data_in` using with the specified hash function, writing the output to
-    /// `digest_out`, returning the size of the digest written to `digest_out`. If `digest_out` is
-    /// to small to fit the entire digest, it will be truncated. If too large, the leftover space
-    /// will not be overwritten.
-    fn hash(&self, code: u64, data: &[u8]) -> Result<Multihash>;
-}
-
 /// Randomness queries.
 #[delegatable_trait]
 pub trait RandomnessOps {
@@ -341,19 +307,15 @@ pub trait EventOps {
     ) -> Result<()>;
 }
 
-// Unfortunately, I need to do this to make it possible to name these macros by path. I'm hiding
-// this because I really don't want users to glob import the `kernel` module.
-#[doc(hidden)]
-pub use {
-    ambassador_impl_CryptoOps, ambassador_impl_DebugOps, ambassador_impl_EventOps,
-    ambassador_impl_IpldBlockOps, ambassador_impl_MessageOps, ambassador_impl_NetworkOps,
-    ambassador_impl_RandomnessOps, ambassador_impl_SelfOps, ambassador_impl_SendOps,
-    ambassador_impl_UpgradeOps,
-};
-
 /// Import this module (with a glob) if you're implementing a kernel, _especially_ if you want to
 /// use ambassador to delegate the implementation.
 pub mod prelude {
+    pub use super::{
+        ambassador_impl_ActorOps, ambassador_impl_CryptoOps, ambassador_impl_DebugOps,
+        ambassador_impl_EventOps, ambassador_impl_IpldBlockOps, ambassador_impl_MessageOps,
+        ambassador_impl_NetworkOps, ambassador_impl_RandomnessOps, ambassador_impl_SelfOps,
+        ambassador_impl_SendOps, ambassador_impl_UpgradeOps,
+    };
     pub use super::{
         ActorOps, CryptoOps, DebugOps, EventOps, IpldBlockOps, MessageOps, NetworkOps,
         RandomnessOps, SelfOps, SendOps, UpgradeOps,
@@ -376,12 +338,6 @@ pub mod prelude {
     pub use fvm_shared::version::NetworkVersion;
     pub use fvm_shared::{ActorID, MethodNum};
     pub use multihash::Multihash;
-    pub use {
-        ambassador_impl_ActorOps, ambassador_impl_CryptoOps, ambassador_impl_DebugOps,
-        ambassador_impl_EventOps, ambassador_impl_IpldBlockOps, ambassador_impl_MessageOps,
-        ambassador_impl_NetworkOps, ambassador_impl_RandomnessOps, ambassador_impl_SelfOps,
-        ambassador_impl_SendOps, ambassador_impl_UpgradeOps,
-    };
 }
 
 use prelude::*;

fvm/src/kernel/mod.rs

@@ -6,7 +6,7 @@ publish = false
 
 [target.'cfg(target_arch = "wasm32")'.dependencies]
 fvm_ipld_encoding = { workspace = true }
-fvm_sdk = { workspace = true, default-features = false }
+fvm_sdk = { workspace = true }
 fvm_shared = { workspace = true }
 multihash = { workspace = true, features = ["sha3", "sha2", "ripemd"] }
 minicov = {version = "0.3", optional = true}