Add API docs for secp256k1_instruction and secp256k1_recover

programs/bpf/rust/secp256k1_recover/Cargo.toml

@@ -10,6 +10,8 @@ documentation = "https://docs.rs/solana-bpf-rust-secp256k1-recover"
 edition = "2021"
 
 [dependencies]
+# nb version 7 of this crate is required for running on bpf, 6 does not build
+libsecp256k1 = { version = "0.7.0", default-features = false }
 solana-program = { path = "../../../../sdk/program", version = "=1.11.2" }
 
 [lib]

programs/bpf/rust/secp256k1_recover/src/lib.rs

@@ -1,11 +1,11 @@
 //! Secp256k1Recover Syscall test
 
 extern crate solana_program;
-use solana_program::{custom_heap_default, custom_panic_default, msg};
+use solana_program::{
+    custom_heap_default, custom_panic_default, msg, secp256k1_recover::secp256k1_recover,
+};
 
 fn test_secp256k1_recover() {
-    use solana_program::secp256k1_recover::secp256k1_recover;
-
     let expected: [u8; 64] = [
         0x42, 0xcd, 0x27, 0xe4, 0x0f, 0xdf, 0x7c, 0x97, 0x0a, 0xa2, 0xca, 0x0b, 0x88, 0x5b, 0x96,
         0x0f, 0x8b, 0x62, 0x8a, 0x41, 0xa1, 0x81, 0xe7, 0xe6, 0x8e, 0x03, 0xea, 0x0b, 0x84, 0x20,
@@ -32,11 +32,57 @@ fn test_secp256k1_recover() {
     assert_eq!(public_key.to_bytes(), expected);
 }
 
+/// secp256k1_recover allows malleable signatures
+fn test_secp256k1_recover_malleability() {
+    let message = b"hello world";
+    let message_hash = {
+        let mut hasher = solana_program::keccak::Hasher::default();
+        hasher.hash(message);
+        hasher.result()
+    };
+
+    let pubkey_bytes: [u8; 64] = [
+        0x9B, 0xEE, 0x7C, 0x18, 0x34, 0xE0, 0x18, 0x21, 0x7B, 0x40, 0x14, 0x9B, 0x84, 0x2E, 0xFA,
+        0x80, 0x96, 0x00, 0x1A, 0x9B, 0x17, 0x88, 0x01, 0x80, 0xA8, 0x46, 0x99, 0x09, 0xE9, 0xC4,
+        0x73, 0x6E, 0x39, 0x0B, 0x94, 0x00, 0x97, 0x68, 0xC2, 0x28, 0xB5, 0x55, 0xD3, 0x0C, 0x0C,
+        0x42, 0x43, 0xC1, 0xEE, 0xA5, 0x0D, 0xC0, 0x48, 0x62, 0xD3, 0xAE, 0xB0, 0x3D, 0xA2, 0x20,
+        0xAC, 0x11, 0x85, 0xEE,
+    ];
+    let signature_bytes: [u8; 64] = [
+        0x93, 0x92, 0xC4, 0x6C, 0x42, 0xF6, 0x31, 0x73, 0x81, 0xD4, 0xB2, 0x44, 0xE9, 0x2F, 0xFC,
+        0xE3, 0xF4, 0x57, 0xDD, 0x50, 0xB3, 0xA5, 0x20, 0x26, 0x3B, 0xE7, 0xEF, 0x8A, 0xB0, 0x69,
+        0xBB, 0xDE, 0x2F, 0x90, 0x12, 0x93, 0xD7, 0x3F, 0xA0, 0x29, 0x0C, 0x46, 0x4B, 0x97, 0xC5,
+        0x00, 0xAD, 0xEA, 0x6A, 0x64, 0x4D, 0xC3, 0x8D, 0x25, 0x24, 0xEF, 0x97, 0x6D, 0xC6, 0xD7,
+        0x1D, 0x9F, 0x5A, 0x26,
+    ];
+    let recovery_id: u8 = 0;
+
+    let pubkey = libsecp256k1::PublicKey::parse_slice(&pubkey_bytes, None).unwrap();
+    let signature = libsecp256k1::Signature::parse_standard_slice(&signature_bytes).unwrap();
+
+    // Flip the S value in the signature to make a different but valid signature.
+    let mut alt_signature = signature.clone();
+    alt_signature.s = -alt_signature.s;
+    let alt_recovery_id = libsecp256k1::RecoveryId::parse(recovery_id ^ 1).unwrap();
+
+    let alt_signature_bytes = alt_signature.serialize();
+    let alt_recovery_id = alt_recovery_id.serialize();
+
+    let recovered_pubkey =
+        secp256k1_recover(&message_hash.0, recovery_id, &signature_bytes[..]).unwrap();
+    assert_eq!(recovered_pubkey.to_bytes(), pubkey_bytes);
+
+    let alt_recovered_pubkey =
+        secp256k1_recover(&message_hash.0, alt_recovery_id, &alt_signature_bytes[..]).unwrap();
+    assert_eq!(alt_recovered_pubkey.to_bytes(), pubkey_bytes);
+}
+
 #[no_mangle]
 pub extern "C" fn entrypoint(_input: *mut u8) -> u64 {
     msg!("secp256k1_recover");
 
     test_secp256k1_recover();
+    test_secp256k1_recover_malleability();
 
     0
 }

sdk/Cargo.toml

@@ -86,6 +86,7 @@ js-sys = "0.3.57"
 [dev-dependencies]
 anyhow = "1.0.57"
 curve25519-dalek = "3.2.1"
+hex = "0.4.3"
 static_assertions = "1.1.0"
 tiny-bip39 = "0.8.2"
 

sdk/program/src/example_mocks.rs

@@ -113,7 +113,7 @@ pub mod solana_client {
 /// programs.
 pub mod solana_sdk {
     pub use crate::{
-        address_lookup_table_account, hash, instruction, message, nonce,
+        address_lookup_table_account, hash, instruction, keccak, message, nonce,
         pubkey::{self, Pubkey},
         system_instruction, system_program,
     };
@@ -178,6 +178,7 @@ pub mod solana_sdk {
 
         pub trait Signers {}
 
+        impl<T: Signer> Signers for [&T] {}
         impl<T: Signer> Signers for [&T; 1] {}
         impl<T: Signer> Signers for [&T; 2] {}
     }

sdk/program/src/secp256k1_program.rs

@@ -1,5 +1,10 @@
 //! The [secp256k1 native program][np].
 //!
 //! [np]: https://docs.solana.com/developing/runtime-facilities/programs#secp256k1-program
+//!
+//! Constructors for secp256k1 program instructions, and documentation on the
+//! program's usage can be found in [`solana_sdk::secp256k1_instruction`].
+//!
+//! [`solana_sdk::secp256k1_instruction`]: https://docs.rs/solana-sdk/latest/solana_sdk/secp256k1_instruction/index.html
 
 crate::declare_id!("KeccakSecp256k11111111111111111111111111111");