Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Evaluator #120

Draft
wants to merge 3 commits into
base: main
Choose a base branch
from
Draft

Evaluator #120

wants to merge 3 commits into from

Conversation

chriseth
Copy link
Collaborator

No description provided.

@chriseth chriseth changed the base branch from main to execution_position October 28, 2022 08:37
chriseth
chriseth commented Oct 28, 2022
View reviewed changes
src/encoder.rs
@@ -29,6 +30,7 @@ pub struct Encoder<InstructionsType> {
ssa_tracker: SSATracker,
output: Vec<SMTStatement>,
interpreter: InstructionsType,
Copy link
Collaborator Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

We probably want to change this name now.

leonardoalt
leonardoalt reviewed Oct 28, 2022
View reviewed changes
src/evm_builtins.rs
@@ -99,14 +99,14 @@ impl Instructions for EVMInstructions {
"calldatasize" => single_return(evm_context::calldatasize(ssa).into()),
"calldatacopy" => panic!("Builtin {} not implemented", builtin.name), // TODO
"codesize" => single_return(evm_context::codesize(ssa).into()),
"codecopy" => panic!("Builtin {} not implemented", builtin.name), // TODO
"codecopy" => vec![], //panic!("Builtin {} not implemented", builtin.name), // TODO
Copy link
Owner

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Shouldn't this and extcodecopy havoc memory?

Copy link
Collaborator Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Yes, this is just to prevent the system from crashing on my example.

@chriseth
Copy link
Collaborator Author

chriseth commented Nov 1, 2022

This now uses the evaluator to determine if some branches cannot be reached at all (and then it does not encode them). This is a trace of the encoded opcodes filtered to mstore, datacopy, create, sload, sstore and call, executed on two transactions: First a call to "setUp()" and then "proveA()" (i.e. calldata is set accordingly). You can see that it does not encode any of the panics in the abi decoder and properly re-retrieves the address of the contract under test from storage:

=========== SETUP ===================
mstore(64, 128)
mstore(0, 35408467139433450592217433187231851964531694900788300625387963629091585785856)
mstore(4, 65)
datacopy(128, dataoffset("oTest_15"), datasize("oTest_15"))
_54 := create(0, 128, $_53)
   - _54 = address<oTest_15,0>
_75 := sload(0)
sstore(0, address<oTest_15,0>)
=========== CALL ===================
mstore(64, 128)
_68 := sload(0)
   - _68 = address<oTest_15,0>
mstore(128, 8964389696657244788749362684448106728022753484683927377131620019041577467904)
mstore(132, 0)
mstore(164, 0)
_110 := call($_106, address<oTest_15,0>, 0, 128, 68, 128, 32)
mstore(0, 35408467139433450592217433187231851964531694900788300625387963629091585785856)
mstore(4, 65)
mstore(64, $newFreePtr_113_1)
mstore(0, 35408467139433450592217433187231851964531694900788300625387963629091585785856)
mstore(4, 17)
mstore(0, 35408467139433450592217433187231851964531694900788300625387963629091585785856)
mstore(4, 1)

@chriseth
Copy link
Collaborator Author

chriseth commented Nov 2, 2022

Got this working now without the hack:

=========== SETUP ===================
mstore(40, 80)
mstore(0, 4e487b7100000000000000000000000000000000000000000000000000000000)
mstore(4, 41)
datacopy(80, dataoffset(dataref("oTest_15")), datasize(dataref("oTest_15")))
_54 := create(0, 80, sub(add(add(80, datasize(dataref("oTest_15"))), 0), 80))
   - _54 = address<oTest_15,0>
_75 := sload(0)
sstore(0, or(and($value_49_0, ffffffffffffffffffffffff0000000000000000000000000000000000000000), address<oTest_15,0>))
=========== CALL ===================
mstore(40, 80)
_70 := sload(0)
   - _70 = or(and($value_49_0, ffffffffffffffffffffffff0000000000000000000000000000000000000000), address<oTest_15,0>)
mstore(80, 13d1aa2e00000000000000000000000000000000000000000000000000000000)
mstore(84, 0)
mstore(a4, 0)
_112 := call($_108, address<oTest_15,0>, 0, 80, 44, 80, 20)
mstore(0, 4e487b7100000000000000000000000000000000000000000000000000000000)
mstore(4, 41)
mstore(40, add(80, and(add($value_108_0, 1f), ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffe0)))
mstore(0, 4e487b7100000000000000000000000000000000000000000000000000000000)
mstore(4, 11)
mstore(0, 4e487b7100000000000000000000000000000000000000000000000000000000)
mstore(4, 1)

@chriseth chriseth force-pushed the execution_position branch 2 times, most recently from 718e6f7 to 97486c6 Compare November 15, 2022 22:07
Base automatically changed from execution_position to main November 28, 2022 12:07
@chriseth chriseth force-pushed the evaluator branch 4 times, most recently from 7859944 to 13f6b19 Compare January 2, 2023 15:15
@chriseth chriseth changed the base branch from main to shorter_literals January 3, 2023 15:37
Base automatically changed from shorter_literals to main January 4, 2023 12:26
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Reviewers

@leonardoalt leonardoalt leonardoalt left review comments

Assignees
No one assigned
Labels
None yet
Projects
None yet
Milestone
No milestone
Development

Successfully merging this pull request may close these issues.
2 participants
@chriseth @leonardoalt