Implement EIP-4788 for Cancun

evm_arithmetization/src/cpu/kernel/aggregator.rs

@@ -13,6 +13,7 @@ pub(crate) fn combined_kernel() -> Kernel {
     let files = vec![
         "global jumped_to_0: PANIC",
         "global jumped_to_1: PANIC",
+        include_str!("asm/beacon_roots.asm"),
         include_str!("asm/bignum/add.asm"),
         include_str!("asm/bignum/addmul.asm"),
         include_str!("asm/bignum/cmp.asm"),

evm_arithmetization/src/cpu/kernel/asm/beacon_roots.asm

@@ -0,0 +1,48 @@
+/// EIP-4788: Beacon block root in the EVM
+/// <https://eips.ethereum.org/EIPS/eip-4788#pseudocode>
+
+global set_beacon_root:
+    PUSH start_txn
+    %timestamp
+    // stack: timestamp, start_txns
+    PUSH @HISTORY_BUFFER_LENGTH
+    DUP2
+    // stack: timestamp, 8191, timestamp, start_txns
+    MOD
+    // stack: timestamp_idx, timestamp, start_txns
+    PUSH write_beacon_roots_to_storage
+    %parent_beacon_block_root
+    // stack: calldata, write_beacon_roots_to_storage, timestamp_idx, timestamp, start_txns
+    DUP3
+    %add_const(@HISTORY_BUFFER_LENGTH)
+    // stack: root_idx, calldata, write_beacon_roots_to_storage, timestamp_idx, timestamp, start_txns
+
+write_beacon_roots_to_storage:
+    // stack: slot, value, retdest
+     // First we write the value to MPT data, and get a pointer to it.
+    %get_trie_data_size
+    // stack: value_ptr, slot, value, retdest
+    SWAP2
+    // stack: value, slot, value_ptr, retdest
+    %append_to_trie_data
+    // stack: slot, value_ptr, retdest
+
+    // Next, call mpt_insert on the current account's storage root.
+    %stack (slot, value_ptr) -> (slot, value_ptr, after_beacon_roots_storage_insert)
+    %slot_to_storage_key
+    // stack: storage_key, value_ptr, after_beacon_roots_storage_insert, retdest
+    PUSH 64 // storage_key has 64 nibbles
+    %get_storage_trie(@BEACON_ROOTS_ADDRESS)
+    // stack: storage_root_ptr, 64, storage_key, value_ptr, after_beacon_roots_storage_insert, retdest
+    %jump(mpt_insert)
+
+after_beacon_roots_storage_insert:
+    // stack: new_storage_root_ptr, retdest
+    %get_account_data(@BEACON_ROOTS_ADDRESS)
+    // stack: account_ptr, new_storage_root_ptr, retdest
+
+    // Update the copied account with our new storage root pointer.
+    %add_const(2)
+    // stack: account_storage_root_ptr_ptr, new_storage_root_ptr, retdest
+    %mstore_trie_data
+    JUMP

evm_arithmetization/src/cpu/kernel/asm/main.asm

@@ -41,10 +41,13 @@ global hash_initial_tries:
     // stack: trie_data_full_len
     %mstore_global_metadata(@GLOBAL_METADATA_TRIE_DATA_SIZE)
 
+    // If txn_idx == 0, update the beacon_root.
+    %mload_global_metadata(@GLOBAL_METADATA_TXN_NUMBER_BEFORE)
+    ISZERO
+    %jumpi(set_beacon_root)
+
 global start_txn:
     // stack: (empty)
-    // The special case of an empty trie (i.e. for the first transaction)
-    // is handled outside of the kernel.
     %mload_global_metadata(@GLOBAL_METADATA_TXN_NUMBER_BEFORE)
     // stack: txn_nb
     DUP1 %scalar_to_rlp

evm_arithmetization/src/cpu/kernel/asm/memory/metadata.asm

@@ -447,3 +447,7 @@ global sys_prevrandao:
     %mload_global_metadata(@GLOBAL_METADATA_BLOCK_RANDOM)
     %stack (random, kexit_info) -> (kexit_info, random)
     EXIT_KERNEL
+
+%macro parent_beacon_block_root
+    %mload_global_metadata(@GLOBAL_METADATA_PARENT_BEACON_BLOCK_ROOT)
+%endmacro

evm_arithmetization/src/cpu/kernel/asm/mpt/accounts.asm

@@ -19,3 +19,25 @@
     %mload_trie_data
     // stack: storage_root_ptr
 %endmacro
+
+// Return a pointer to the provided account's data in the state trie.
+%macro get_account_data(addr)
+    PUSH $addr %mpt_read_state_trie
+    // stack: account_ptr
+    // account_ptr should be non-null as long as the prover provided the proper
+    // Merkle data. But a bad prover may not have, and we don't want return a
+    // null pointer for security reasons.
+    DUP1 ISZERO %jumpi(panic)
+    // stack: account_ptr
+%endmacro
+
+// Returns a pointer to the root of the storage trie associated with the provided account.
+%macro get_storage_trie(addr)
+    // stack: (empty)
+    %get_account_data($addr)
+    // stack: account_ptr
+    %add_const(2)
+    // stack: storage_root_ptr_ptr
+    %mload_trie_data
+    // stack: storage_root_ptr
+%endmacro

evm_arithmetization/src/cpu/kernel/asm/mpt/insert/insert.asm

@@ -20,7 +20,7 @@ global mpt_insert:
 global mpt_insert_hash_node:
     PANIC
 
-mpt_insert_empty:
+global mpt_insert_empty:
     // stack: node_type, node_payload_ptr, num_nibbles, key, value_ptr, retdest
     %pop2
     // stack: num_nibbles, key, value_ptr, retdest
@@ -38,7 +38,7 @@ mpt_insert_empty:
     SWAP1
     JUMP
 
-mpt_insert_branch:
+global mpt_insert_branch:
     // stack: node_type, node_payload_ptr, num_nibbles, key, value_ptr, retdest
     POP
 

evm_arithmetization/src/cpu/kernel/asm/mpt/read.asm

@@ -106,7 +106,7 @@ global mpt_read_extension_not_found:
     // Not found; return 0.
     %stack (key_part, future_nibbles, key, node_payload_ptr, retdest) -> (retdest, 0)
     JUMP
-mpt_read_extension_found:
+global mpt_read_extension_found:
     // stack: key_part, future_nibbles, key, node_payload_ptr, retdest
     DUP2 %mul_const(4) SHL // key_part_shifted = (key_part << (future_nibbles * 4))
     // stack: key_part_shifted, future_nibbles, key, node_payload_ptr, retdest
@@ -121,7 +121,7 @@ mpt_read_extension_found:
     // stack: child_ptr, future_nibbles, key, retdest
     %jump(mpt_read) // recurse
 
-mpt_read_leaf:
+global mpt_read_leaf:
     // stack: node_type, node_payload_ptr, num_nibbles, key, retdest
     POP
     // stack: node_payload_ptr, num_nibbles, key, retdest
@@ -142,7 +142,7 @@ global mpt_read_leaf_not_found:
     // Not found; return 0.
     %stack (node_payload_ptr, retdest) -> (retdest, 0)
     JUMP
-mpt_read_leaf_found:
+global mpt_read_leaf_found:
     // stack: node_payload_ptr, retdest
     %add_const(2) // The value pointer is located after num_nibbles and the key.
     // stack: value_ptr_ptr, retdest

evm_arithmetization/src/cpu/kernel/constants/global_metadata.rs

@@ -56,6 +56,8 @@ pub(crate) enum GlobalMetadata {
     BlockGasUsedAfter,
     /// Current block header hash
     BlockCurrentHash,
+    /// EIP-4788: hash tree root of the beacon chain parent block.
+    ParentBeaconBlockRoot,
 
     /// Gas to refund at the end of the transaction.
     RefundCounter,
@@ -101,7 +103,7 @@ pub(crate) enum GlobalMetadata {
 }
 
 impl GlobalMetadata {
-    pub(crate) const COUNT: usize = 49;
+    pub(crate) const COUNT: usize = 50;
 
     /// Unscales this virtual offset by their respective `Segment` value.
     pub(crate) const fn unscale(&self) -> usize {
@@ -134,6 +136,7 @@ impl GlobalMetadata {
             Self::BlockGasUsed,
             Self::BlockGasUsedBefore,
             Self::BlockGasUsedAfter,
+            Self::ParentBeaconBlockRoot,
             Self::RefundCounter,
             Self::AccessedAddressesLen,
             Self::AccessedStorageKeysLen,
@@ -190,6 +193,7 @@ impl GlobalMetadata {
             Self::BlockGasUsedBefore => "GLOBAL_METADATA_BLOCK_GAS_USED_BEFORE",
             Self::BlockGasUsedAfter => "GLOBAL_METADATA_BLOCK_GAS_USED_AFTER",
             Self::BlockCurrentHash => "GLOBAL_METADATA_BLOCK_CURRENT_HASH",
+            Self::ParentBeaconBlockRoot => "GLOBAL_METADATA_PARENT_BEACON_BLOCK_ROOT",
             Self::RefundCounter => "GLOBAL_METADATA_REFUND_COUNTER",
             Self::AccessedAddressesLen => "GLOBAL_METADATA_ACCESSED_ADDRESSES_LEN",
             Self::AccessedStorageKeysLen => "GLOBAL_METADATA_ACCESSED_STORAGE_KEYS_LEN",

evm_arithmetization/src/cpu/kernel/constants/mod.rs

@@ -1,13 +1,14 @@
 use std::collections::HashMap;
 
-use ethereum_types::U256;
+use ethereum_types::{H256, U256};
 use hex_literal::hex;
 
 use crate::cpu::kernel::constants::context_metadata::ContextMetadata;
 use crate::cpu::kernel::constants::global_metadata::GlobalMetadata;
 use crate::cpu::kernel::constants::journal_entry::JournalEntry;
 use crate::cpu::kernel::constants::trie_type::PartialTrieType;
 use crate::cpu::kernel::constants::txn_fields::NormalizedTxnField;
+use crate::generation::mpt::AccountRlp;
 use crate::memory::segments::Segment;
 
 pub(crate) mod context_metadata;
@@ -56,6 +57,14 @@ pub(crate) fn evm_constants() -> HashMap<String, U256> {
 
     c.insert(MAX_NONCE.0.into(), U256::from(MAX_NONCE.1));
     c.insert(CALL_STACK_LIMIT.0.into(), U256::from(CALL_STACK_LIMIT.1));
+    c.insert(
+        cancun_constants::BEACON_ROOTS_ADDRESS.0.into(),
+        U256::from_big_endian(&cancun_constants::BEACON_ROOTS_ADDRESS.1),
+    );
+    c.insert(
+        cancun_constants::HISTORY_BUFFER_LENGTH.0.into(),
+        cancun_constants::HISTORY_BUFFER_LENGTH.1.into(),
+    );
 
     for segment in Segment::all() {
         c.insert(segment.var_name().into(), (segment as usize).into());
@@ -285,3 +294,33 @@ const CODE_SIZE_LIMIT: [(&str, u64); 3] = [
 
 const MAX_NONCE: (&str, u64) = ("MAX_NONCE", 0xffffffffffffffff);
 const CALL_STACK_LIMIT: (&str, u64) = ("CALL_STACK_LIMIT", 1024);
+
+/// Cancun-related constants
+/// See <https://eips.ethereum.org/EIPS/eip-4788#deployment>.
+pub mod cancun_constants {
+    use super::*;
+
+    pub const BEACON_ROOTS_ADDRESS: (&str, [u8; 20]) = (
+        "BEACON_ROOTS_ADDRESS",
+        hex!("000F3df6D732807Ef1319fB7B8bB8522d0Beac02"),
+    );
+
+    pub const HISTORY_BUFFER_LENGTH: (&str, u64) = ("HISTORY_BUFFER_LENGTH", 8191);
+
+    pub const BEACON_ROOTS_CONTRACT_CODE: [u8; 106] = hex!("60618060095f395ff33373fffffffffffffffffffffffffffffffffffffffe14604d57602036146024575f5ffd5b5f35801560495762001fff810690815414603c575f5ffd5b62001fff01545f5260205ff35b5f5ffd5b62001fff42064281555f359062001fff015500");
+    pub const BEACON_ROOTS_CONTRACT_CODE_HASH: [u8; 32] =
+        hex!("468e991a328ab315e08296896adc222230a4960692e90cb6e096006ba6ae75d5");
+
+    pub const BEACON_ROOTS_CONTRACT_ADDRESS_HASHED: [u8; 32] =
+        hex!("37d65eaa92c6bc4c13a5ec45527f0c18ea8932588728769ec7aecfe6d9f32e42");
+
+    pub const BEACON_ROOTS_ACCOUNT: AccountRlp = AccountRlp {
+        nonce: U256::zero(),
+        balance: U256::zero(),
+        // Storage root for this account at genesis.
+        storage_root: H256(hex!(
+            "f58e5f1eae7ce386de44266ff0286a88dafe7e4269c1ffa97f79dbbcf4f59e5c"
+        )),
+        code_hash: H256(BEACON_ROOTS_CONTRACT_CODE_HASH),
+    };
+}

evm_arithmetization/src/cpu/kernel/mod.rs

@@ -11,6 +11,9 @@ pub mod stack;
 mod utils;
 
 pub(crate) mod interpreter;
+
+pub use constants::cancun_constants;
+
 #[cfg(test)]
 mod tests;