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

Mode to disable backward jumps on Neo AppEngine 3 #837

Closed
wants to merge 18 commits into from
Closed

Mode to disable backward jumps on Neo AppEngine 3 #837

Changes from 2 commits
Commits
Show all changes
18 commits
Select commit Hold shift + click to select a range
5cdd28e
Mode to disable backward jumps on Neo AppEngine 3
igormcoelho Jun 17, 2019
0aafb26
Merge branch 'master' into feat_3x_neoapp_limited_mode
shargon Jun 17, 2019
668c160
Merge branch 'master' into feat_3x_neoapp_limited_mode
vncoelho Jul 5, 2019
c75b4e9
Merge branch 'master' into feat_3x_neoapp_limited_mode
lock9 Jul 23, 2019
e0ad7ef
Merge branch 'master' into feat_3x_neoapp_limited_mode
shargon Aug 6, 2019
bb1731d
Merge branch 'master' of https://github.com/neo-project/neo into feat…
igormcoelho Aug 11, 2019
75cf115
basic tests, no jumps on verification
igormcoelho Aug 11, 2019
8ee60a2
recursion not blocked yet
igormcoelho Aug 11, 2019
39215b6
Merge branch 'master' into feat_3x_neoapp_limited_mode
igormcoelho Aug 15, 2019
8688f38
Optimization
shargon Aug 16, 2019
e896027
Reuse var
shargon Aug 16, 2019
b1cc6a7
Update neo.UnitTests/Network/P2P/Payloads/UT_Transaction.cs
igormcoelho Aug 17, 2019
b72e8f9
Merge branch 'master' into feat_3x_neoapp_limited_mode
shargon Aug 18, 2019
3381b5e
Split unit tests
shargon Aug 18, 2019
97330bd
Merge remote-tracking branch 'igormcoelho/feat_3x_neoapp_limited_mode…
shargon Aug 18, 2019
d1c03c0
Merge branch 'master' into feat_3x_neoapp_limited_mode
shargon Aug 25, 2019
13ba5b0
Merge branch 'master' into feat_3x_neoapp_limited_mode
lock9 Sep 11, 2019
93f4734
Merge branch 'master' into feat_3x_neoapp_limited_mode
lock9 Sep 13, 2019
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
26 changes: 25 additions & 1 deletion neo/SmartContract/ApplicationEngine.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -15,6 +15,8 @@ public partial class ApplicationEngine : ExecutionEngine
public const long GasFree = 0;
private readonly long gas_amount;
private readonly bool testMode;
// limited mode (disallow backward jumps and recursive calls)
private readonly bool isLimited;
private readonly RandomAccessStack<UInt160> hashes = new RandomAccessStack<UInt160>();
private readonly List<NotifyEventArgs> notifications = new List<NotifyEventArgs>();
private readonly List<IDisposable> disposables = new List<IDisposable>();
Expand All @@ -29,10 +31,11 @@ public partial class ApplicationEngine : ExecutionEngine
public IReadOnlyList<NotifyEventArgs> Notifications => notifications;
internal Dictionary<UInt160, int> InvocationCounter { get; } = new Dictionary<UInt160, int>();

public ApplicationEngine(TriggerType trigger, IVerifiable container, Snapshot snapshot, long gas, bool testMode = false)
public ApplicationEngine(TriggerType trigger, IVerifiable container, Snapshot snapshot, long gas, bool testMode = false, bool isLimited = false)
{
this.gas_amount = GasFree + gas;
this.testMode = testMode;
this.isLimited = isLimited;
this.Trigger = trigger;
this.ScriptContainer = container;
this.Snapshot = snapshot;
Expand Down Expand Up @@ -81,6 +84,27 @@ protected override bool PreExecuteInstruction()
{
if (CurrentContext.InstructionPointer >= CurrentContext.Script.Length)
return true;

Instruction instruction = CurrentContext.CurrentInstruction;
switch(instruction.OpCode)
{
case OpCode.JMP:
case OpCode.JMPIF:
case OpCode.JMPIFNOT:
case OpCode.CALL:
Copy link
Member

Choose a reason for hiding this comment

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

With syscall, you can jump to your own contract again

Copy link
Contributor Author

@igormcoelho igormcoelho Jun 17, 2019 •
edited
Loading

Choose a reason for hiding this comment

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

From what we've been talking, most syscalls will probably be disabled on verification. In my opinion now, only crypto stuff and block header information should be available... no appcalls, no storage, ... so it will be fast as a bullet and state independent.

{
if(isLimited)
{
// no backwards jump in limited mode
if(instruction.TokenI16 <= 0)
{
return false;
}
}
break;
}
}

return AddGas(OpCodePrices[CurrentContext.CurrentInstruction.OpCode]);
}

Expand Down