public void Generate()
{
List <BoogieVariable> inParams = new List <BoogieVariable>()
{
new BoogieFormalParam(new BoogieTypedIdent("from", BoogieType.Ref)),
new BoogieFormalParam(new BoogieTypedIdent("to", BoogieType.Ref)),
new BoogieFormalParam(new BoogieTypedIdent("amount", BoogieType.Int))
};
List <BoogieVariable> outParams = new List <BoogieVariable>();
List <BoogieAttribute> attributes = new List <BoogieAttribute>()
{
new BoogieAttribute("inline", 1),
};
var procName = "FallbackDispatch";
BoogieProcedure procedure = new BoogieProcedure(procName, inParams, outParams, attributes);
context.Program.AddDeclaration(procedure);
List <BoogieVariable> localVars = new List <BoogieVariable>();
var fbUnknownProcName = "Fallback_UnknownType";
BoogieStmtList procBody = GenerateBodyOfFallbackDispatch(inParams, fbUnknownProcName);
BoogieImplementation implementation = new BoogieImplementation(procName, inParams, outParams, localVars, procBody);
context.Program.AddDeclaration(implementation);
// let us havoc all the global variables when fallback_unknowntype is called
var modSet = context.Program.Declarations.Where(x => x is BoogieGlobalVariable).Select(x => (BoogieGlobalVariable)x).ToList();
BoogieProcedure unknownFbProc = new BoogieProcedure(fbUnknownProcName, inParams, outParams, attributes);
context.Program.AddDeclaration(unknownFbProc);
// we need to create an implementation as Corral seem to ignore modifies on declarations
// https://github.com/boogie-org/corral/issues/98
BoogieStmtList fbBody = new BoogieStmtList();
var fbLocalVars = new List <BoogieVariable>();
if (context.TranslateFlags.ModelStubsAsSkips() || context.TranslateFlags.ModelStubsAsCallbacks())
{
fbBody.AppendStmtList(CreateBodyOfUnknownFallback(fbLocalVars, inParams));
}
else
{
Debug.Assert(context.TranslateFlags.ModelStubsAsHavocs(), "Unknown option for modeling stubs");
foreach (var global in modSet)
{
fbBody.AddStatement(new BoogieHavocCmd(new BoogieIdentifierExpr(global.Name)));
}
}
BoogieImplementation unknownFbImpl = new BoogieImplementation(fbUnknownProcName, inParams, outParams, fbLocalVars, fbBody);
context.Program.AddDeclaration(unknownFbImpl);
}
private BoogieStmtList CreateBodyOfUnknownFallback(List <BoogieVariable> fbLocalVars, List <BoogieVariable> inParams)
{
Debug.Assert(context.TranslateFlags.ModelStubsAsSkips() || context.TranslateFlags.ModelStubsAsCallbacks() || context.TranslateFlags.ModelStubsAsMultipleCallbacks(),
"CreateBodyOfUnknownFallback called in unexpected context");
var procBody = new BoogieStmtList();
/*procBody.AddStatement(new BoogieCommentCmd("---- Logic for payable function START "));
* var balnSender = new BoogieMapSelect(new BoogieIdentifierExpr("Balance"), new BoogieIdentifierExpr(inParams[0].Name));
* var balnThis = new BoogieMapSelect(new BoogieIdentifierExpr("Balance"), new BoogieIdentifierExpr(inParams[1].Name));
* var msgVal = new BoogieIdentifierExpr("amount");
* //assume Balance[msg.sender] >= msg.value
* procBody.AddStatement(new BoogieAssumeCmd(new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.GE, balnSender, msgVal)));
* //balance[from] = balance[from] - msg.value
* procBody.AddStatement(new BoogieAssignCmd(balnSender, new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.SUB, balnSender, msgVal)));
* //balance[to] = balance[to] + msg.value
* procBody.AddStatement(new BoogieAssignCmd(balnThis, new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.ADD, balnThis, msgVal)));
* procBody.AddStatement(new BoogieCommentCmd("---- Logic for payable function END "));*/
BoogieStmtList body = procBody;
if (context.TranslateFlags.ModelStubsAsCallbacks() ||
context.TranslateFlags.ModelStubsAsMultipleCallbacks())
{
if (context.TranslateFlags.ModelReverts)
{
BoogieBinaryOperation revertGuard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.EQ, new BoogieIdentifierExpr("choice"), new BoogieLiteralExpr(BigInteger.Zero));
BoogieStmtList thenBody = new BoogieStmtList();
thenBody.AddStatement(new BoogieAssignCmd(new BoogieIdentifierExpr("revert"), new BoogieLiteralExpr(true)));
thenBody.AddStatement(new BoogieReturnCmd());
BoogieIfCmd earlyExitCmd = new BoogieIfCmd(revertGuard, thenBody, null);
body.AddStatement(earlyExitCmd);
}
if (context.TranslateFlags.InstrumentGas)
{
BoogieBinaryOperation gasGuard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.LT, new BoogieIdentifierExpr("gas"), new BoogieLiteralExpr(TranslatorContext.TX_GAS_COST));
BoogieIfCmd earlyExitCmd = new BoogieIfCmd(gasGuard, BoogieStmtList.MakeSingletonStmtList(new BoogieReturnCmd()), null);
body.AddStatement(earlyExitCmd);
}
}
if (context.TranslateFlags.ModelStubsAsMultipleCallbacks())
{
fbLocalVars.Add(new BoogieLocalVariable(new BoogieTypedIdent("iterate", BoogieType.Bool)));
BoogieBinaryOperation gasGuard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.GE, new BoogieIdentifierExpr("gas"), new BoogieLiteralExpr(TranslatorContext.TX_GAS_COST));
BoogieBinaryOperation guard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.AND, new BoogieIdentifierExpr("iterate"), gasGuard);
BoogieStmtList loopBody = new BoogieStmtList();
procBody.AddStatement(new BoogieWhileCmd(guard, loopBody, new List <BoogieExpr>()));
body = loopBody;
}
if (context.TranslateFlags.ModelStubsAsCallbacks() || context.TranslateFlags.ModelStubsAsMultipleCallbacks())
{
List <BoogieVariable> localVars = TransUtils.CollectLocalVars(context.ContractDefinitions.ToList(), context);
fbLocalVars.AddRange(localVars);
// if (*) fn1(from, *, ...)
// we only redirect the calling contract, but the msg.sender need not be to, as it can call into anohter contract that calls
// into from
if (context.TranslateFlags.ModelStubsAsMultipleCallbacks())
{
body.AppendStmtList(HavocLocals(localVars));
body.AddStatement(new BoogieHavocCmd(new BoogieIdentifierExpr("iterate")));
}
BoogieIfCmd typeIf = null;
foreach (ContractDefinition curDef in context.ContractDefinitions.ToList())
{
BoogieIfCmd reentrantCalls = TransUtils.GenerateChoiceBlock(new List <ContractDefinition>()
{
curDef
},
context, false, Tuple.Create(inParams[0].Name, inParams[1].Name));
if (reentrantCalls == null)
{
continue;
}
BoogieExpr dtype = new BoogieMapSelect(new BoogieIdentifierExpr("DType"), new BoogieIdentifierExpr(inParams[0].Name));
BoogieBinaryOperation guard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.EQ, dtype, new BoogieIdentifierExpr(curDef.Name));
typeIf = new BoogieIfCmd(guard, BoogieStmtList.MakeSingletonStmtList(reentrantCalls), typeIf == null ? null : BoogieStmtList.MakeSingletonStmtList(typeIf));
}
/*BoogieIfCmd ifCmd = null;
*
* if (context.TranslateFlags.ModelReverts)
* {
* BoogieExpr guard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.EQ,
* new BoogieIdentifierExpr("choice"),
* new BoogieLiteralExpr(choices.Item2 + 1));
*
* BoogieAssignCmd assign = new BoogieAssignCmd(new BoogieIdentifierExpr("revert"), new BoogieLiteralExpr(true));
* ifCmd = new BoogieIfCmd(guard, BoogieStmtList.MakeSingletonStmtList(assign), BoogieStmtList.MakeSingletonStmtList(choices.Item1));
* }
* else
* {
* ifCmd = choices.Item1;
* }*/
body.AddStatement(typeIf);
}
return(procBody);
}
public static Tuple <BoogieIfCmd, int> GeneratePartialChoiceBlock(List <ContractDefinition> contracts, TranslatorContext context, BoogieExpr thisExpr, int startingPoint, bool canRevert, BoogieIfCmd alternatives = null, Tuple <string, string> callBackTarget = null)
{
BoogieIfCmd ifCmd = alternatives;
int j = startingPoint;
foreach (var contract in contracts)
{
if (contract.ContractKind != EnumContractKind.CONTRACT)
{
continue;
}
HashSet <FunctionDefinition> funcDefs = context.GetVisibleFunctionsByContract(contract);
List <FunctionDefinition> publicFuncDefs = new List <FunctionDefinition>();
foreach (FunctionDefinition funcDef in funcDefs)
{
if (funcDef.IsConstructor)
{
continue;
}
if (funcDef.IsFallback)
{
continue; //let us not call fallback directly in harness
}
if (context.TranslateFlags.PerformFunctionSlice &&
!context.TranslateFlags.SliceFunctions.Contains(funcDef))
{
continue;
}
if (funcDef.Visibility == EnumVisibility.PUBLIC || funcDef.Visibility == EnumVisibility.EXTERNAL)
{
publicFuncDefs.Add(funcDef);
}
}
for (int i = publicFuncDefs.Count - 1; i >= 0; --i)
{
j++;
BoogieExpr guard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.EQ,
new BoogieIdentifierExpr("choice"),
new BoogieLiteralExpr(j));
BoogieStmtList thenBody = new BoogieStmtList();
FunctionDefinition funcDef = publicFuncDefs[i];
string callee = TransUtils.GetCanonicalFunctionName(funcDef, context);
List <BoogieExpr> inputs = new List <BoogieExpr>()
{
// let us just call back into the calling contract
callBackTarget != null ? new BoogieIdentifierExpr(callBackTarget.Item1) : thisExpr,
callBackTarget != null ? new BoogieIdentifierExpr(callBackTarget.Item2) : new BoogieIdentifierExpr("msgsender_MSG"),
new BoogieIdentifierExpr("msgvalue_MSG"),
};
var inpParamCount = 0;
foreach (VariableDeclaration param in funcDef.Parameters.Parameters)
{
string name = $"__arg_{inpParamCount++}_" + funcDef.Name;
if (!string.IsNullOrEmpty(param.Name))
{
name = TransUtils.GetCanonicalLocalVariableName(param, context);
}
BoogieIdentifierExpr boogieVar = new BoogieIdentifierExpr(name);
inputs.Add(boogieVar);
if (param.TypeName is ArrayTypeName array)
{
thenBody.AddStatement(new BoogieCallCmd(
"FreshRefGenerator",
new List <BoogieExpr>(), new List <BoogieIdentifierExpr>()
{
new BoogieIdentifierExpr(name)
}));
}
thenBody.AppendStmtList(constrainVarValues(context, param, boogieVar));
}
List <BoogieIdentifierExpr> outputs = new List <BoogieIdentifierExpr>();
var retParamCount = 0;
foreach (VariableDeclaration param in funcDef.ReturnParameters.Parameters)
{
string name = $"__ret_{retParamCount++}_" + funcDef.Name;
if (!string.IsNullOrEmpty(param.Name))
{
name = TransUtils.GetCanonicalLocalVariableName(param, context);
}
outputs.Add(new BoogieIdentifierExpr(name));
}
if (funcDef.StateMutability.Equals(EnumStateMutability.PAYABLE))
{
BoogieExpr assumeExpr = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.GE,
new BoogieIdentifierExpr("msgvalue_MSG"), new BoogieLiteralExpr(BigInteger.Zero));
thenBody.AddStatement(new BoogieAssumeCmd(assumeExpr));
if (!canRevert)
{
thenBody.AddStatement(new BoogieCommentCmd("---- Logic for payable function START "));
var balnSender = new BoogieMapSelect(new BoogieIdentifierExpr("Balance"), new BoogieIdentifierExpr("msgsender_MSG"));
var balnThis = new BoogieMapSelect(new BoogieIdentifierExpr("Balance"), new BoogieIdentifierExpr("this"));
var msgVal = new BoogieIdentifierExpr("msgvalue_MSG");
//assume Balance[msg.sender] >= msg.value
thenBody.AddStatement(new BoogieAssumeCmd(new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.GE, balnSender, msgVal)));
//balance[msg.sender] = balance[msg.sender] - msg.value
thenBody.AddStatement(new BoogieAssignCmd(balnSender, new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.SUB, balnSender, msgVal)));
//balance[this] = balance[this] + msg.value
thenBody.AddStatement(new BoogieAssignCmd(balnThis, new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.ADD, balnThis, msgVal)));
thenBody.AddStatement(new BoogieCommentCmd("---- Logic for payable function END "));
}
}
else
{
BoogieExpr assumeExpr = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.EQ,
new BoogieIdentifierExpr("msgvalue_MSG"), new BoogieLiteralExpr(BigInteger.Zero));
thenBody.AddStatement(new BoogieAssumeCmd(assumeExpr));
}
BoogieCallCmd callCmd = new BoogieCallCmd(callee, inputs, outputs);
thenBody.AddStatement(callCmd);
if (context.TranslateFlags.InstrumentGas)
{
var gasVar = new BoogieIdentifierExpr("gas");
BoogieBinaryOperation gasGuard = new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.GE, gasVar, new BoogieLiteralExpr(BigInteger.Zero));
BoogieIfCmd ifExpr = new BoogieIfCmd(gasGuard, thenBody, null);
thenBody = new BoogieStmtList();
//thenBody.AddStatement(new BoogieAssumeCmd(new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.GE, gasVar, new BoogieLiteralExpr(TranslatorContext.TX_GAS_COST))));
thenBody.AddStatement(new BoogieAssignCmd(gasVar, new BoogieBinaryOperation(BoogieBinaryOperation.Opcode.SUB, gasVar, new BoogieLiteralExpr(TranslatorContext.TX_GAS_COST))));
thenBody.AddStatement(ifExpr);
}
BoogieStmtList elseBody = ifCmd == null ? null : BoogieStmtList.MakeSingletonStmtList(ifCmd);
ifCmd = new BoogieIfCmd(guard, thenBody, elseBody);
}
}
return(new Tuple <BoogieIfCmd, int>(ifCmd, j));
}