Files
codeql/python/ql/test/experimental/dataflow/coverage/argumentRouting1.ql
2020-11-02 23:02:29 +01:00

49 lines
1.9 KiB
Plaintext

/**
* @kind path-problem
*/
import python
import semmle.python.dataflow.new.DataFlow
import DataFlow::PathGraph
private import semmle.python.dataflow.new.internal.DataFlowPrivate as DataFlowPrivate
/**
* A configuration to check routing of arguments through magic methods.
*/
class ArgumentRoutingConfig extends DataFlow::Configuration {
ArgumentRoutingConfig() { this = "ArgumentRoutingConfig" }
override predicate isSource(DataFlow::Node node) {
node.(DataFlow::CfgNode).getNode().(NameNode).getId() = "arg1"
or
exists(AssignmentDefinition def, DataFlowPrivate::DataFlowCall call |
def.getVariable() = node.(DataFlow::EssaNode).getVar() and
def.getValue() = call.getNode() and
call.getNode().(CallNode).getFunction().(NameNode).getId().matches("With\\_%")
) and
node.(DataFlow::EssaNode).getVar().getName().matches("with\\_%")
}
override predicate isSink(DataFlow::Node node) {
exists(CallNode call |
call.getFunction().(NameNode).getId() = "SINK1" and
node.(DataFlow::CfgNode).getNode() = call.getAnArg()
)
}
/**
* We want to be able to use `arg` in a sequence of calls such as `func(kw=arg); ... ; func(arg)`.
* Use-use flow lets the argument to the first call reach the sink inside the second call,
* making it seem like we handle all cases even if we only handle the last one.
* We make the test honest by preventing flow into source nodes.
*/
override predicate isBarrierIn(DataFlow::Node node) { isSource(node) }
}
from DataFlow::PathNode source, DataFlow::PathNode sink
where
source.getNode().getLocation().getFile().getBaseName() in ["classes.py", "argumentPassing.py"] and
sink.getNode().getLocation().getFile().getBaseName() in ["classes.py", "argumentPassing.py"] and
exists(ArgumentRoutingConfig cfg | cfg.hasFlowPath(source, sink))
select source.getNode(), source, sink, "Flow found"