public UCFG Create(SyntaxNode syntaxNode, IMethodSymbol methodSymbol, IControlFlowGraph cfg)
{
try
{
var ucfg = new UCFG
{
Location = syntaxNode.GetUcfgLocation(),
MethodId = methodSymbol.ToUcfgMethodId()
};
ucfg.BasicBlocks.AddRange(cfg.Blocks.Select(this.blockBuilder.CreateBasicBlock));
ucfg.Parameters.AddRange(methodSymbol.GetParameters().Select(p => p.Name));
if (syntaxNode is BaseMethodDeclarationSyntax methodDeclaration &&
TaintAnalysisEntryPointDetector.IsEntryPoint(methodSymbol))
{
var entryPointBlock = this.blockBuilder.CreateEntryPointBlock(methodDeclaration, methodSymbol, this.blockIdProvider.Get(cfg.EntryBlock));
ucfg.BasicBlocks.Add(entryPointBlock);
ucfg.Entries.Add(entryPointBlock.Id);
}
else
{
ucfg.Entries.Add(this.blockIdProvider.Get(cfg.EntryBlock));
}
return(ucfg);
}
protected /*for testing*/ virtual void WriteProtobuf(UCFG ucfg, string fileName)
{
using (var stream = File.Create(fileName))
{
ucfg.WriteTo(stream);
}
}
private static string GetProtobufMethodId(string protobufPath)
{
File.Exists(protobufPath).Should().BeTrue($"File {protobufPath} must exist.");
using (var stream = File.OpenRead(protobufPath))
{
var ucfg = new UCFG();
ucfg.MergeFrom(stream);
return(ucfg.MethodId);
}
}
public static string Serialize(UCFG ucfg)
{
var stringBuilder = new StringBuilder();
using (var writer = new StringWriter(stringBuilder))
{
Serialize(ucfg, writer);
}
return(stringBuilder.ToString());
}
internal /*for testing*/ static bool IsValid(UCFG ucfg)
{
var existingBlockIds = new HashSet <string>(ucfg.BasicBlocks.Select(b => b.Id));
return(ucfg.BasicBlocks.All(HasTerminator) &&
ucfg.BasicBlocks.All(JumpsToExistingBlock) &&
ucfg.Entries.All(existingBlockIds.Contains));
bool HasTerminator(BasicBlock block) =>
block.Jump != null || block.Ret != null;
bool JumpsToExistingBlock(BasicBlock block) =>
block.Jump == null || block.Jump.Destinations.All(existingBlockIds.Contains);
}
public void Ucfg_Block_Without_Terminator_IsInvalid()
{
var ucfg = new UCFG
{
Entries = { "0" },
BasicBlocks =
{
new BasicBlock {
Id = "0"
}, // no Jump or Ret
},
};
ReviewSqlQueriesForSecurityVulnerabilities.IsValid(ucfg).Should().BeFalse();
}
public void Ucfg_Block_Without_Terminator_IsInvalid()
{
var ucfg = new UCFG
{
Entries = { "0" },
BasicBlocks =
{
new BasicBlock {
Id = "0"
}, // no Jump or Ret
},
};
UcfgGenerator.IsValid(ucfg).Should().BeFalse();
}
public UCFG Build(SemanticModel semanticModel, SyntaxNode syntaxNode, IMethodSymbol methodSymbol, IControlFlowGraph cfg)
{
var ucfg = new UCFG
{
MethodId = GetMethodId(methodSymbol),
Location = GetLocation(syntaxNode),
};
ucfg.BasicBlocks.AddRange(cfg.Blocks.Select(b => CreateBasicBlock(b, semanticModel)));
ucfg.Parameters.AddRange(methodSymbol.GetParameters().Select(p => p.Name));
if (syntaxNode is BaseMethodDeclarationSyntax methodDeclaration &&
EntryPointRecognizer.IsEntryPoint(methodSymbol))
{
var entryPointBlock = CreateEntryPointBlock(semanticModel, methodDeclaration, methodSymbol, blockId.Get(cfg.EntryBlock));
ucfg.BasicBlocks.Add(entryPointBlock);
ucfg.Entries.Add(entryPointBlock.Id);
}
public void Ucfg_Block_With_Jump_IsValid()
{
var ucfg = new UCFG
{
Entries = { "0" },
BasicBlocks =
{
new BasicBlock
{
Id = "0",
Jump = new Jump{
Destinations ={ "0" }
},
},
},
};
ReviewSqlQueriesForSecurityVulnerabilities.IsValid(ucfg).Should().BeTrue();
}
public void Ucfg_Block_With_Missing_Jump_Destinations_IsInvalid()
{
var ucfg = new UCFG
{
Entries = { "0" },
BasicBlocks =
{
new BasicBlock
{
Id = "0",
Jump = new Jump{
Destinations ={ "1" }
}, // There is no such block
},
},
};
UcfgGenerator.IsValid(ucfg).Should().BeFalse();
}
public void Ucfg_Block_With_Jump_IsValid()
{
var ucfg = new UCFG
{
Entries = { "0" },
BasicBlocks =
{
new BasicBlock
{
Id = "0",
Jump = new Jump{
Destinations ={ "0" }
},
},
},
};
UcfgGenerator.IsValid(ucfg).Should().BeTrue();
}
public void Ucfg_Block_With_Missing_Jump_Destinations_IsInvalid()
{
var ucfg = new UCFG
{
Entries = { "0" },
BasicBlocks =
{
new BasicBlock
{
Id = "0",
Jump = new Jump{
Destinations ={ "1" }
}, // There is no such block
},
},
};
ReviewSqlQueriesForSecurityVulnerabilities.IsValid(ucfg).Should().BeFalse();
}
private static void VerifyInstructions(string codeSnippet, UCFG ucfg)
{
var expectedInstructions = UcfgInstructionCollector.Collect(codeSnippet).ToList();
var actualInstructions = ucfg.BasicBlocks
.SelectMany(b => b.Instructions)
.Select(UcfgTestHelper.ToTestString)
.ToList();
Console.WriteLine("Expected instructions:{0}{1}", Environment.NewLine, string.Join(Environment.NewLine, expectedInstructions));
Console.WriteLine();
Console.WriteLine("Actual instructions:{0}{1}", Environment.NewLine, string.Join(Environment.NewLine, actualInstructions));
// Fluent assertion bug: just comparing the collections gives an incorrect error message if the expected
// list is empty but the actual list isn't ("Expected collection to be equal to {empty}, but found empty collection.")
// To avoid this, do an assertion on the number of items first.
actualInstructions.Count.Should().Be(expectedInstructions.Count);
actualInstructions.Should().Equal(expectedInstructions);
}
public void Visit(string methodName, UCFG ucfg)
{
writer.WriteGraphStart(methodName);
writer.WriteNode(EntryBlockId, EntryBlockId, ucfg.Parameters.ToArray());
foreach (var entry in ucfg.Entries)
{
writer.WriteEdge(EntryBlockId, entry, string.Empty);
}
foreach (var block in ucfg.BasicBlocks)
{
Visit(block);
}
writer.WriteNode(ExitBlockId, ExitBlockId);
writer.WriteGraphEnd();
}
public void Ucfg_Block_With_Ret_IsValid()
{
var ucfg = new UCFG
{
Entries = { "0" },
BasicBlocks =
{
new BasicBlock
{
Id = "0",
Ret = new Return
{
ReturnedExpression = new Expression{
Var = new Variable{
Name = "a"
}
}
},
},
},
};
UcfgGenerator.IsValid(ucfg).Should().BeTrue();
}
public void Ucfg_Block_With_Ret_IsValid()
{
var ucfg = new UCFG
{
Entries = { "0" },
BasicBlocks =
{
new BasicBlock
{
Id = "0",
Ret = new Return
{
ReturnedExpression = new Expression{
Var = new Variable{
Name = "a"
}
}
},
},
},
};
ReviewSqlQueriesForSecurityVulnerabilities.IsValid(ucfg).Should().BeTrue();
}
public static IList <Instruction> GetEntryPointInstructions(UCFG ucfg)
{
return(ucfg.BasicBlocks.SelectMany(
b => b.Instructions.Where(i => i.Assigncall?.MethodId == UcfgBuiltInMethodId.EntryPoint)).ToList());
}
public static void Serialize(UCFG ucfg, TextWriter writer)
{
new UcfgWalker(new DotWriter(writer)).Visit(ucfg.MethodId, ucfg);
}