revm_handler/
frame.rs

1use crate::{
2    evm::FrameTr, item_or_result::FrameInitOrResult, precompile_provider::PrecompileProvider,
3    CallFrame, CreateFrame, FrameData, FrameResult, ItemOrResult,
4};
5use context::result::FromStringError;
6use context_interface::{
7    context::ContextError,
8    journaled_state::{JournalCheckpoint, JournalTr},
9    local::{FrameToken, OutFrame},
10    Cfg, ContextTr, Database,
11};
12use core::cmp::min;
13use derive_where::derive_where;
14use interpreter::{
15    gas,
16    interpreter::{EthInterpreter, ExtBytecode},
17    interpreter_action::FrameInit,
18    interpreter_types::ReturnData,
19    CallInput, CallInputs, CallOutcome, CallValue, CreateInputs, CreateOutcome, CreateScheme,
20    FrameInput, Gas, InputsImpl, InstructionResult, Interpreter, InterpreterAction,
21    InterpreterResult, InterpreterTypes, SharedMemory,
22};
23use primitives::{
24    constants::CALL_STACK_LIMIT,
25    hardfork::SpecId::{self, HOMESTEAD, LONDON, SPURIOUS_DRAGON},
26    keccak256, Address, Bytes, U256,
27};
28use state::Bytecode;
29use std::{borrow::ToOwned, boxed::Box, vec::Vec};
30
31/// Frame implementation for Ethereum.
32#[derive_where(Clone, Debug; IW,
33    <IW as InterpreterTypes>::Stack,
34    <IW as InterpreterTypes>::Memory,
35    <IW as InterpreterTypes>::Bytecode,
36    <IW as InterpreterTypes>::ReturnData,
37    <IW as InterpreterTypes>::Input,
38    <IW as InterpreterTypes>::RuntimeFlag,
39    <IW as InterpreterTypes>::Extend,
40)]
41pub struct EthFrame<IW: InterpreterTypes = EthInterpreter> {
42    /// Frame-specific data (Call, Create, or EOFCreate).
43    pub data: FrameData,
44    /// Input data for the frame.
45    pub input: FrameInput,
46    /// Current call depth in the execution stack.
47    pub depth: usize,
48    /// Journal checkpoint for state reversion.
49    pub checkpoint: JournalCheckpoint,
50    /// Interpreter instance for executing bytecode.
51    pub interpreter: Interpreter<IW>,
52    /// Whether the frame has been finished its execution.
53    /// Frame is considered finished if it has been called and returned a result.
54    pub is_finished: bool,
55}
56
57impl<IT: InterpreterTypes> FrameTr for EthFrame<IT> {
58    type FrameResult = FrameResult;
59    type FrameInit = FrameInit;
60}
61
62impl Default for EthFrame<EthInterpreter> {
63    fn default() -> Self {
64        Self::do_default(Interpreter::default())
65    }
66}
67
68impl EthFrame<EthInterpreter> {
69    /// Creates an new invalid [`EthFrame`].
70    pub fn invalid() -> Self {
71        Self::do_default(Interpreter::invalid())
72    }
73
74    fn do_default(interpreter: Interpreter<EthInterpreter>) -> Self {
75        Self {
76            data: FrameData::Call(CallFrame {
77                return_memory_range: 0..0,
78            }),
79            input: FrameInput::Empty,
80            depth: 0,
81            checkpoint: JournalCheckpoint::default(),
82            interpreter,
83            is_finished: false,
84        }
85    }
86
87    /// Returns true if the frame has finished execution.
88    pub fn is_finished(&self) -> bool {
89        self.is_finished
90    }
91
92    /// Sets the finished state of the frame.
93    pub fn set_finished(&mut self, finished: bool) {
94        self.is_finished = finished;
95    }
96}
97
98/// Type alias for database errors from a context.
99pub type ContextTrDbError<CTX> = <<CTX as ContextTr>::Db as Database>::Error;
100
101impl EthFrame<EthInterpreter> {
102    /// Clear and initialize a frame.
103    #[allow(clippy::too_many_arguments)]
104    pub fn clear(
105        &mut self,
106        data: FrameData,
107        input: FrameInput,
108        depth: usize,
109        memory: SharedMemory,
110        bytecode: ExtBytecode,
111        inputs: InputsImpl,
112        is_static: bool,
113        spec_id: SpecId,
114        gas_limit: u64,
115        checkpoint: JournalCheckpoint,
116    ) {
117        let Self {
118            data: data_ref,
119            input: input_ref,
120            depth: depth_ref,
121            interpreter,
122            checkpoint: checkpoint_ref,
123            is_finished: is_finished_ref,
124        } = self;
125        *data_ref = data;
126        *input_ref = input;
127        *depth_ref = depth;
128        *is_finished_ref = false;
129        interpreter.clear(memory, bytecode, inputs, is_static, spec_id, gas_limit);
130        *checkpoint_ref = checkpoint;
131    }
132
133    /// Make call frame
134    #[inline]
135    pub fn make_call_frame<
136        CTX: ContextTr,
137        PRECOMPILES: PrecompileProvider<CTX, Output = InterpreterResult>,
138        ERROR: From<ContextTrDbError<CTX>> + FromStringError,
139    >(
140        mut this: OutFrame<'_, Self>,
141        ctx: &mut CTX,
142        precompiles: &mut PRECOMPILES,
143        depth: usize,
144        memory: SharedMemory,
145        inputs: Box<CallInputs>,
146    ) -> Result<ItemOrResult<FrameToken, FrameResult>, ERROR> {
147        let gas = Gas::new(inputs.gas_limit);
148        let return_result = |instruction_result: InstructionResult| {
149            Ok(ItemOrResult::Result(FrameResult::Call(CallOutcome {
150                result: InterpreterResult {
151                    result: instruction_result,
152                    gas,
153                    output: Bytes::new(),
154                },
155                memory_offset: inputs.return_memory_offset.clone(),
156                was_precompile_called: false,
157                precompile_call_logs: Vec::new(),
158            })))
159        };
160
161        // Check depth
162        if depth > CALL_STACK_LIMIT as usize {
163            return return_result(InstructionResult::CallTooDeep);
164        }
165
166        // Create subroutine checkpoint
167        let checkpoint = ctx.journal_mut().checkpoint();
168
169        // Touch address. For "EIP-158 State Clear", this will erase empty accounts.
170        if let CallValue::Transfer(value) = inputs.value {
171            // Transfer value from caller to called account
172            // Target will get touched even if balance transferred is zero.
173            if let Some(i) =
174                ctx.journal_mut()
175                    .transfer_loaded(inputs.caller, inputs.target_address, value)
176            {
177                ctx.journal_mut().checkpoint_revert(checkpoint);
178                return return_result(i.into());
179            }
180        }
181
182        let interpreter_input = InputsImpl {
183            target_address: inputs.target_address,
184            caller_address: inputs.caller,
185            bytecode_address: Some(inputs.bytecode_address),
186            input: inputs.input.clone(),
187            call_value: inputs.value.get(),
188        };
189        let is_static = inputs.is_static;
190        let gas_limit = inputs.gas_limit;
191
192        if let Some(result) = precompiles.run(ctx, &inputs).map_err(ERROR::from_string)? {
193            let mut logs = Vec::new();
194            if result.result.is_ok() {
195                ctx.journal_mut().checkpoint_commit();
196            } else {
197                // clone logs that precompile created, only possible with custom precompiles.
198                // checkpoint.log_i will be always correct.
199                logs = ctx.journal_mut().logs()[checkpoint.log_i..].to_vec();
200                ctx.journal_mut().checkpoint_revert(checkpoint);
201            }
202            return Ok(ItemOrResult::Result(FrameResult::Call(CallOutcome {
203                result,
204                memory_offset: inputs.return_memory_offset.clone(),
205                was_precompile_called: true,
206                precompile_call_logs: logs,
207            })));
208        }
209
210        // Get bytecode and hash - either from known_bytecode or load from account
211        let (bytecode, bytecode_hash) = if let Some((hash, code)) = inputs.known_bytecode.clone() {
212            // Use provided bytecode and hash
213            (code, hash)
214        } else {
215            // Load account and get its bytecode
216            let account = ctx
217                .journal_mut()
218                .load_account_with_code(inputs.bytecode_address)?;
219            (
220                account.info.code.clone().unwrap_or_default(),
221                account.info.code_hash,
222            )
223        };
224
225        // Returns success if bytecode is empty.
226        if bytecode.is_empty() {
227            ctx.journal_mut().checkpoint_commit();
228            return return_result(InstructionResult::Stop);
229        }
230
231        // Create interpreter and executes call and push new CallStackFrame.
232        this.get(EthFrame::invalid).clear(
233            FrameData::Call(CallFrame {
234                return_memory_range: inputs.return_memory_offset.clone(),
235            }),
236            FrameInput::Call(inputs),
237            depth,
238            memory,
239            ExtBytecode::new_with_hash(bytecode, bytecode_hash),
240            interpreter_input,
241            is_static,
242            ctx.cfg().spec().into(),
243            gas_limit,
244            checkpoint,
245        );
246        Ok(ItemOrResult::Item(this.consume()))
247    }
248
249    /// Make create frame.
250    #[inline]
251    pub fn make_create_frame<
252        CTX: ContextTr,
253        ERROR: From<ContextTrDbError<CTX>> + FromStringError,
254    >(
255        mut this: OutFrame<'_, Self>,
256        context: &mut CTX,
257        depth: usize,
258        memory: SharedMemory,
259        inputs: Box<CreateInputs>,
260    ) -> Result<ItemOrResult<FrameToken, FrameResult>, ERROR> {
261        let spec = context.cfg().spec().into();
262        let return_error = |e| {
263            Ok(ItemOrResult::Result(FrameResult::Create(CreateOutcome {
264                result: InterpreterResult {
265                    result: e,
266                    gas: Gas::new(inputs.gas_limit),
267                    output: Bytes::new(),
268                },
269                address: None,
270            })))
271        };
272
273        // Check depth
274        if depth > CALL_STACK_LIMIT as usize {
275            return return_error(InstructionResult::CallTooDeep);
276        }
277
278        // Fetch balance of caller.
279        let mut caller_info = context.journal_mut().load_account_mut(inputs.caller)?;
280
281        // Check if caller has enough balance to send to the created contract.
282        // decrement of balance is done in the create_account_checkpoint.
283        if *caller_info.balance() < inputs.value {
284            return return_error(InstructionResult::OutOfFunds);
285        }
286
287        // Increase nonce of caller and check if it overflows
288        let old_nonce = caller_info.nonce();
289        if !caller_info.bump_nonce() {
290            return return_error(InstructionResult::Return);
291        };
292
293        // Create address
294        let mut init_code_hash = None;
295        let created_address = match inputs.scheme {
296            CreateScheme::Create => inputs.caller.create(old_nonce),
297            CreateScheme::Create2 { salt } => {
298                let init_code_hash = *init_code_hash.insert(keccak256(&inputs.init_code));
299                inputs.caller.create2(salt.to_be_bytes(), init_code_hash)
300            }
301            CreateScheme::Custom { address } => address,
302        };
303
304        // warm load account.
305        context.journal_mut().load_account(created_address)?;
306
307        // Create account, transfer funds and make the journal checkpoint.
308        let checkpoint = match context.journal_mut().create_account_checkpoint(
309            inputs.caller,
310            created_address,
311            inputs.value,
312            spec,
313        ) {
314            Ok(checkpoint) => checkpoint,
315            Err(e) => return return_error(e.into()),
316        };
317
318        let bytecode = ExtBytecode::new_with_optional_hash(
319            Bytecode::new_legacy(inputs.init_code.clone()),
320            init_code_hash,
321        );
322
323        let interpreter_input = InputsImpl {
324            target_address: created_address,
325            caller_address: inputs.caller,
326            bytecode_address: None,
327            input: CallInput::Bytes(Bytes::new()),
328            call_value: inputs.value,
329        };
330        let gas_limit = inputs.gas_limit;
331
332        this.get(EthFrame::invalid).clear(
333            FrameData::Create(CreateFrame { created_address }),
334            FrameInput::Create(inputs),
335            depth,
336            memory,
337            bytecode,
338            interpreter_input,
339            false,
340            spec,
341            gas_limit,
342            checkpoint,
343        );
344        Ok(ItemOrResult::Item(this.consume()))
345    }
346
347    /// Initializes a frame with the given context and precompiles.
348    pub fn init_with_context<
349        CTX: ContextTr,
350        PRECOMPILES: PrecompileProvider<CTX, Output = InterpreterResult>,
351    >(
352        this: OutFrame<'_, Self>,
353        ctx: &mut CTX,
354        precompiles: &mut PRECOMPILES,
355        frame_init: FrameInit,
356    ) -> Result<
357        ItemOrResult<FrameToken, FrameResult>,
358        ContextError<<<CTX as ContextTr>::Db as Database>::Error>,
359    > {
360        // TODO cleanup inner make functions
361        let FrameInit {
362            depth,
363            memory,
364            frame_input,
365        } = frame_init;
366
367        match frame_input {
368            FrameInput::Call(inputs) => {
369                Self::make_call_frame(this, ctx, precompiles, depth, memory, inputs)
370            }
371            FrameInput::Create(inputs) => Self::make_create_frame(this, ctx, depth, memory, inputs),
372            FrameInput::Empty => unreachable!(),
373        }
374    }
375}
376
377impl EthFrame<EthInterpreter> {
378    /// Processes the next interpreter action, either creating a new frame or returning a result.
379    pub fn process_next_action<
380        CTX: ContextTr,
381        ERROR: From<ContextTrDbError<CTX>> + FromStringError,
382    >(
383        &mut self,
384        context: &mut CTX,
385        next_action: InterpreterAction,
386    ) -> Result<FrameInitOrResult<Self>, ERROR> {
387        let spec = context.cfg().spec().into();
388
389        // Run interpreter
390
391        let mut interpreter_result = match next_action {
392            InterpreterAction::NewFrame(frame_input) => {
393                let depth = self.depth + 1;
394                return Ok(ItemOrResult::Item(FrameInit {
395                    frame_input,
396                    depth,
397                    memory: self.interpreter.memory.new_child_context(),
398                }));
399            }
400            InterpreterAction::Return(result) => result,
401        };
402
403        // Handle return from frame
404        let result = match &self.data {
405            FrameData::Call(frame) => {
406                // return_call
407                // Revert changes or not.
408                if interpreter_result.result.is_ok() {
409                    context.journal_mut().checkpoint_commit();
410                } else {
411                    context.journal_mut().checkpoint_revert(self.checkpoint);
412                }
413                ItemOrResult::Result(FrameResult::Call(CallOutcome::new(
414                    interpreter_result,
415                    frame.return_memory_range.clone(),
416                )))
417            }
418            FrameData::Create(frame) => {
419                let max_code_size = context.cfg().max_code_size();
420                let is_eip3541_disabled = context.cfg().is_eip3541_disabled();
421                return_create(
422                    context.journal_mut(),
423                    self.checkpoint,
424                    &mut interpreter_result,
425                    frame.created_address,
426                    max_code_size,
427                    is_eip3541_disabled,
428                    spec,
429                );
430
431                ItemOrResult::Result(FrameResult::Create(CreateOutcome::new(
432                    interpreter_result,
433                    Some(frame.created_address),
434                )))
435            }
436        };
437
438        Ok(result)
439    }
440
441    /// Processes a frame result and updates the interpreter state accordingly.
442    pub fn return_result<CTX: ContextTr, ERROR: From<ContextTrDbError<CTX>> + FromStringError>(
443        &mut self,
444        ctx: &mut CTX,
445        result: FrameResult,
446    ) -> Result<(), ERROR> {
447        self.interpreter.memory.free_child_context();
448        match core::mem::replace(ctx.error(), Ok(())) {
449            Err(ContextError::Db(e)) => return Err(e.into()),
450            Err(ContextError::Custom(e)) => return Err(ERROR::from_string(e)),
451            Ok(_) => (),
452        }
453
454        // Insert result to the top frame.
455        match result {
456            FrameResult::Call(outcome) => {
457                let out_gas = outcome.gas();
458                let ins_result = *outcome.instruction_result();
459                let returned_len = outcome.result.output.len();
460
461                let interpreter = &mut self.interpreter;
462                let mem_length = outcome.memory_length();
463                let mem_start = outcome.memory_start();
464                interpreter.return_data.set_buffer(outcome.result.output);
465
466                let target_len = min(mem_length, returned_len);
467
468                if ins_result == InstructionResult::FatalExternalError {
469                    panic!("Fatal external error in insert_call_outcome");
470                }
471
472                let item = if ins_result.is_ok() {
473                    U256::from(1)
474                } else {
475                    U256::ZERO
476                };
477                // Safe to push without stack limit check
478                let _ = interpreter.stack.push(item);
479
480                // Return unspend gas.
481                if ins_result.is_ok_or_revert() {
482                    interpreter.gas.erase_cost(out_gas.remaining());
483                    interpreter
484                        .memory
485                        .set(mem_start, &interpreter.return_data.buffer()[..target_len]);
486                }
487
488                if ins_result.is_ok() {
489                    interpreter.gas.record_refund(out_gas.refunded());
490                }
491            }
492            FrameResult::Create(outcome) => {
493                let instruction_result = *outcome.instruction_result();
494                let interpreter = &mut self.interpreter;
495
496                if instruction_result == InstructionResult::Revert {
497                    // Save data to return data buffer if the create reverted
498                    interpreter
499                        .return_data
500                        .set_buffer(outcome.output().to_owned());
501                } else {
502                    // Otherwise clear it. Note that RETURN opcode should abort.
503                    interpreter.return_data.clear();
504                };
505
506                assert_ne!(
507                    instruction_result,
508                    InstructionResult::FatalExternalError,
509                    "Fatal external error in insert_eofcreate_outcome"
510                );
511
512                let this_gas = &mut interpreter.gas;
513                if instruction_result.is_ok_or_revert() {
514                    this_gas.erase_cost(outcome.gas().remaining());
515                }
516
517                let stack_item = if instruction_result.is_ok() {
518                    this_gas.record_refund(outcome.gas().refunded());
519                    outcome.address.unwrap_or_default().into_word().into()
520                } else {
521                    U256::ZERO
522                };
523
524                // Safe to push without stack limit check
525                let _ = interpreter.stack.push(stack_item);
526            }
527        }
528
529        Ok(())
530    }
531}
532
533/// Handles the result of a CREATE operation, including validation and state updates.
534pub fn return_create<JOURNAL: JournalTr>(
535    journal: &mut JOURNAL,
536    checkpoint: JournalCheckpoint,
537    interpreter_result: &mut InterpreterResult,
538    address: Address,
539    max_code_size: usize,
540    is_eip3541_disabled: bool,
541    spec_id: SpecId,
542) {
543    // If return is not ok revert and return.
544    if !interpreter_result.result.is_ok() {
545        journal.checkpoint_revert(checkpoint);
546        return;
547    }
548    // Host error if present on execution
549    // If ok, check contract creation limit and calculate gas deduction on output len.
550    //
551    // EIP-3541: Reject new contract code starting with the 0xEF byte
552    if !is_eip3541_disabled
553        && spec_id.is_enabled_in(LONDON)
554        && interpreter_result.output.first() == Some(&0xEF)
555    {
556        journal.checkpoint_revert(checkpoint);
557        interpreter_result.result = InstructionResult::CreateContractStartingWithEF;
558        return;
559    }
560
561    // EIP-170: Contract code size limit to 0x6000 (~25kb)
562    // EIP-7907 increased this limit to 0xc000 (~49kb).
563    if spec_id.is_enabled_in(SPURIOUS_DRAGON) && interpreter_result.output.len() > max_code_size {
564        journal.checkpoint_revert(checkpoint);
565        interpreter_result.result = InstructionResult::CreateContractSizeLimit;
566        return;
567    }
568    let gas_for_code = interpreter_result.output.len() as u64 * gas::CODEDEPOSIT;
569    if !interpreter_result.gas.record_cost(gas_for_code) {
570        // Record code deposit gas cost and check if we are out of gas.
571        // EIP-2 point 3: If contract creation does not have enough gas to pay for the
572        // final gas fee for adding the contract code to the state, the contract
573        // creation fails (i.e. goes out-of-gas) rather than leaving an empty contract.
574        if spec_id.is_enabled_in(HOMESTEAD) {
575            journal.checkpoint_revert(checkpoint);
576            interpreter_result.result = InstructionResult::OutOfGas;
577            return;
578        } else {
579            interpreter_result.output = Bytes::new();
580        }
581    }
582    // If we have enough gas we can commit changes.
583    journal.checkpoint_commit();
584
585    // Do analysis of bytecode straight away.
586    let bytecode = Bytecode::new_legacy(interpreter_result.output.clone());
587
588    // Set code
589    journal.set_code(address, bytecode);
590
591    interpreter_result.result = InstructionResult::Return;
592}
revm_handler/frame.rs

revm_handler/
frame.rs
