feat(tee-proof-verifier): add support for Solidity-compatible pubkey in report_data

This PR is part of the effort to implement on-chain TEE proof
verification. This PR goes hand in hand with:
- matter-labs/zksync-era#3414
- #228

Author: pbeza

Cargo.lock

@@ -15,7 +15,6 @@ clap.workspace = true
 hex.workspace = true
 rand.workspace = true
 secp256k1.workspace = true
-sha3.workspace = true
 teepot.workspace = true
 tracing.workspace = true
 tracing-log.workspace = true

bin/tee-key-preexec/Cargo.toml

@@ -8,9 +8,9 @@
 
 use anyhow::{Context, Result};
 use clap::Parser;
-use secp256k1::{rand, PublicKey, Secp256k1, SecretKey};
-use sha3::{Digest, Keccak256};
+use secp256k1::{rand, Secp256k1};
 use std::{ffi::OsString, os::unix::process::CommandExt, process::Command};
+use teepot::ethereum::public_key_to_ethereum_address;
 use teepot::quote::get_quote;
 use tracing::error;
 use tracing_log::LogTracer;
@@ -29,19 +29,6 @@ struct Args {
     cmd_args: Vec<OsString>,
 }
 
-/// Converts a public key into an Ethereum address by hashing the encoded public key with Keccak256.
-pub fn public_key_to_address(public: &PublicKey) -> [u8; 20] {
-    let public_key_bytes = public.serialize_uncompressed();
-
-    // Skip the first byte (0x04) which indicates uncompressed key
-    let hash: [u8; 32] = Keccak256::digest(&public_key_bytes[1..]).into();
-
-    // Take the last 20 bytes of the hash to get the Ethereum address
-    let mut address = [0u8; 20];
-    address.copy_from_slice(&hash[12..]);
-    address
-}
-
 fn main_with_error() -> Result<()> {
     LogTracer::init().context("Failed to set logger")?;
 
@@ -54,7 +41,7 @@ fn main_with_error() -> Result<()> {
     let mut rng = rand::thread_rng();
     let secp = Secp256k1::new();
     let (signing_key, verifying_key) = secp.generate_keypair(&mut rng);
-    let ethereum_address = public_key_to_address(&verifying_key);
+    let ethereum_address = public_key_to_ethereum_address(&verifying_key);
     let tee_type = match get_quote(ethereum_address.as_ref()) {
         Ok((tee_type, quote)) => {
             // save quote to file
@@ -99,6 +86,8 @@ fn main() -> Result<()> {
 
 #[cfg(test)]
 mod tests {
+    use secp256k1::{PublicKey, Secp256k1, SecretKey};
+
     use super::*;
 
     #[test]
@@ -110,7 +99,7 @@ mod tests {
         let secret_key = SecretKey::from_slice(&secret_key_bytes).unwrap();
         let public_key = PublicKey::from_secret_key(&secp, &secret_key);
         let expected_address = hex::decode("627306090abaB3A6e1400e9345bC60c78a8BEf57").unwrap();
-        let address = public_key_to_address(&public_key);
+        let address = public_key_to_ethereum_address(&public_key);
 
         assert_eq!(address, expected_address.as_slice());
     }

bin/tee-key-preexec/src/main.rs

@@ -12,5 +12,6 @@ anyhow.workspace = true
 clap.workspace = true
 hex.workspace = true
 secp256k1.workspace = true
+sha3.workspace = true
 teepot.workspace = true
 zksync_basic_types.workspace = true

bin/verify-attestation/Cargo.toml

@@ -5,10 +5,13 @@
 
 use anyhow::{Context, Result};
 use clap::{Args, Parser, Subcommand};
-use secp256k1::{ecdsa::Signature, Message, PublicKey};
+use core::convert::TryInto;
+use hex::encode;
+use secp256k1::{Message, PublicKey};
 use std::{fs, io::Read, path::PathBuf, str::FromStr, time::UNIX_EPOCH};
 use teepot::{
     client::TcbLevel,
+    ethereum::recover_signer,
     quote::{error, tee_qv_get_collateral, verify_quote_with_collateral, QuoteVerificationResult},
 };
 use zksync_basic_types::H256;
@@ -87,14 +90,25 @@ fn verify_signature(
     let reportdata = &quote_verification_result.quote.get_report_data();
     let public_key = PublicKey::from_slice(reportdata)?;
     println!("Public key from attestation quote: {}", public_key);
-    let signature_bytes = fs::read(&signature_args.signature_file)?;
-    let signature = Signature::from_compact(&signature_bytes)?;
-    let root_hash_msg = Message::from_digest_slice(&signature_args.root_hash.0)?;
-    if signature.verify(&root_hash_msg, &public_key).is_ok() {
-        println!("Signature verified successfully");
-    } else {
-        println!("Failed to verify signature");
-    }
+    let signature_bytes: &[u8] = &fs::read(&signature_args.signature_file)?;
+    let ethereum_address_from_quote = &quote_verification_result.quote.get_report_data()[..20];
+    let root_hash_bytes = signature_args.root_hash.as_bytes();
+    let root_hash_msg = Message::from_digest_slice(root_hash_bytes)?;
+    let ethereum_address_from_signature =
+        recover_signer(&signature_bytes.try_into()?, &root_hash_msg)?;
+    let verification_successful = ethereum_address_from_signature == ethereum_address_from_quote;
+
+    println!(
+        "Signature '{}' {}. Ethereum address from attestation quote: {}. Ethereum address from signature: {}.",
+        encode(signature_bytes),
+        if verification_successful {
+            "verified successfully"
+        } else {
+            "verification failed"
+        },
+        encode(ethereum_address_from_quote),
+        encode(ethereum_address_from_signature)
+    );
     Ok(())
 }
 

bin/verify-attestation/src/main.rs

@@ -4,16 +4,17 @@
 use crate::{args::AttestationPolicyArgs, client::JsonRpcClient};
 use anyhow::{Context, Result};
 use hex::encode;
-use secp256k1::{constants::PUBLIC_KEY_SIZE, ecdsa::Signature, Message, PublicKey};
+use secp256k1::Message;
 use teepot::{
     client::TcbLevel,
+    ethereum::recover_signer,
     quote::{
         error::QuoteContext, tee_qv_get_collateral, verify_quote_with_collateral,
         QuoteVerificationResult, Report,
     },
 };
 use tracing::{debug, info, warn};
-use zksync_basic_types::{L1BatchNumber, H256};
+use zksync_basic_types::L1BatchNumber;
 
 pub async fn verify_batch_proof(
     quote_verification_result: &QuoteVerificationResult,
@@ -27,22 +28,38 @@ pub async fn verify_batch_proof(
     }
 
     let batch_no = batch_number.0;
-
-    let public_key = PublicKey::from_slice(
-        &quote_verification_result.quote.get_report_data()[..PUBLIC_KEY_SIZE],
-    )?;
-    debug!(batch_no, "public key: {}", public_key);
-
     let root_hash = node_client.get_root_hash(batch_number).await?;
-    debug!(batch_no, "root hash: {}", root_hash);
+    let ethereum_address_from_quote = &quote_verification_result.quote.get_report_data()[..20];
+    let signature_bytes: &[u8; 65] = signature.try_into()?;
+    let root_hash_bytes = root_hash.as_bytes();
+    let root_hash_msg = Message::from_digest_slice(root_hash_bytes)?;
+    let ethereum_address_from_signature = recover_signer(signature_bytes, &root_hash_msg)?;
+    let verification_successful = ethereum_address_from_signature == ethereum_address_from_quote;
+    debug!(
+        batch_no,
+        "Root hash: {}. Ethereum address from the attestation quote: {}. Ethereum address from the signature: {}.",
+        root_hash,
+        encode(ethereum_address_from_quote),
+        encode(ethereum_address_from_signature),
+    );
 
-    let is_verified = verify_signature(signature, public_key, root_hash)?;
-    if is_verified {
-        info!(batch_no, signature = %encode(signature), "Signature verified successfully.");
+    if verification_successful {
+        info!(
+            batch_no,
+            signature = encode(signature),
+            ethereum_address = encode(ethereum_address_from_quote),
+            "Signature verified successfully."
+        );
     } else {
-        warn!(batch_no, signature = %encode(signature), "Failed to verify signature!");
+        warn!(
+            batch_no,
+            signature = encode(signature),
+            ethereum_address_from_signature = encode(ethereum_address_from_signature),
+            ethereum_address_from_quote = encode(ethereum_address_from_quote),
+            "Failed to verify signature!"
+        );
     }
-    Ok(is_verified)
+    Ok(verification_successful)
 }
 
 pub fn verify_attestation_quote(attestation_quote_bytes: &[u8]) -> Result<QuoteVerificationResult> {
@@ -85,12 +102,6 @@ pub fn log_quote_verification_summary(quote_verification_result: &QuoteVerificat
     );
 }
 
-fn verify_signature(signature: &[u8], public_key: PublicKey, root_hash: H256) -> Result<bool> {
-    let signature = Signature::from_compact(signature)?;
-    let root_hash_msg = Message::from_digest_slice(&root_hash.0)?;
-    Ok(signature.verify(&root_hash_msg, &public_key).is_ok())
-}
-
 fn is_quote_matching_policy(
     attestation_policy: &AttestationPolicyArgs,
     quote_verification_result: &QuoteVerificationResult,

bin/verify-era-proof-attestation/src/verification.rs

@@ -32,10 +32,12 @@ pkcs8.workspace = true
 rand.workspace = true
 rsa.workspace = true
 rustls.workspace = true
+secp256k1 = { workspace = true, features = ["recovery"] }
 serde.workspace = true
 serde_json.workspace = true
 serde_with.workspace = true
 sha2.workspace = true
+sha3.workspace = true
 signature.workspace = true
 tdx-attest-rs.workspace = true
 thiserror.workspace = true
@@ -47,8 +49,8 @@ x509-cert.workspace = true
 zeroize.workspace = true
 
 [dev-dependencies]
-anyhow.workspace = true
 base64.workspace = true
 testaso.workspace = true
 tokio.workspace = true
 tracing-test.workspace = true
+zksync_basic_types.workspace = true

crates/teepot/Cargo.toml

@@ -0,0 +1,86 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright (c) 2023-2024 Matter Labs
+
+//! Ethereum-specific helper functions for on-chain verification of Intel SGX attestation.
+
+use anyhow::Result;
+use secp256k1::{
+    ecdsa::{RecoverableSignature, RecoveryId},
+    Message, PublicKey, SECP256K1,
+};
+use sha3::{Digest, Keccak256};
+
+/// Equivalent to the ecrecover precompile, ensuring that the signatures we produce off-chain
+/// can be recovered on-chain.
+pub fn recover_signer(sig: &[u8; 65], root_hash: &Message) -> Result<[u8; 20]> {
+    let sig = RecoverableSignature::from_compact(
+        &sig[0..64],
+        RecoveryId::from_i32(sig[64] as i32 - 27)?,
+    )?;
+    let public = SECP256K1.recover_ecdsa(root_hash, &sig)?;
+    Ok(public_key_to_ethereum_address(&public))
+}
+
+/// Converts a public key into an Ethereum address by hashing the encoded public key with Keccak256.
+pub fn public_key_to_ethereum_address(public: &PublicKey) -> [u8; 20] {
+    let public_key_bytes = public.serialize_uncompressed();
+
+    // Skip the first byte (0x04) which indicates uncompressed key
+    let hash: [u8; 32] = Keccak256::digest(&public_key_bytes[1..]).into();
+
+    // Take the last 20 bytes of the hash to get the Ethereum address
+    let mut address = [0u8; 20];
+    address.copy_from_slice(&hash[12..]);
+    address
+}
+
+#[cfg(test)]
+mod tests {
+    use secp256k1::{Secp256k1, SecretKey};
+    use zksync_basic_types::H256;
+
+    use super::*;
+
+    /// Signs the message in Ethereum-compatible format for on-chain verification.
+    fn sign_message(sec: &SecretKey, message: Message) -> Result<[u8; 65]> {
+        let s = SECP256K1.sign_ecdsa_recoverable(&message, sec);
+        let (rec_id, data) = s.serialize_compact();
+
+        let mut signature = [0u8; 65];
+        signature[..64].copy_from_slice(&data);
+        // as defined in the Ethereum Yellow Paper (Appendix F)
+        // https://ethereum.github.io/yellowpaper/paper.pdf
+        signature[64] = 27 + rec_id.to_i32() as u8;
+
+        Ok(signature)
+    }
+
+    #[test]
+    fn recover() {
+        // Decode the sample secret key, generate the public key, and derive the Ethereum address
+        // from the public key
+        let secp = Secp256k1::new();
+        let secret_key_bytes =
+            hex::decode("c87509a1c067bbde78beb793e6fa76530b6382a4c0241e5e4a9ec0a0f44dc0d3")
+                .unwrap();
+        let secret_key = SecretKey::from_slice(&secret_key_bytes).unwrap();
+        let public_key = PublicKey::from_secret_key(&secp, &secret_key);
+        let expected_address = hex::decode("627306090abaB3A6e1400e9345bC60c78a8BEf57").unwrap();
+        let address = public_key_to_ethereum_address(&public_key);
+
+        assert_eq!(address, expected_address.as_slice());
+
+        // Generate a random root hash, create a message from the hash, and sign the message using
+        // the secret key
+        let root_hash = H256::random();
+        let root_hash_bytes = root_hash.as_bytes();
+        let msg_to_sign = Message::from_digest_slice(root_hash_bytes).unwrap();
+        let signature = sign_message(&secret_key, msg_to_sign).unwrap();
+
+        // Recover the signer's Ethereum address from the signature and the message, and verify it
+        // matches the expected address
+        let proof_addr = recover_signer(&signature, &msg_to_sign).unwrap();
+
+        assert_eq!(proof_addr, expected_address.as_slice());
+    }
+}

crates/teepot/src/ethereum/mod.rs

@@ -7,6 +7,7 @@
 #![deny(clippy::all)]
 
 pub mod client;
+pub mod ethereum;
 pub mod json;
 pub mod log;
 pub mod quote;