C++: Add models-as-data models for ZMQ networking library + wiring.

cpp/ql/lib/semmle/code/cpp/models/Models.qll

@@ -41,3 +41,4 @@ private import implementations.SqLite3
 private import implementations.PostgreSql
 private import implementations.System
 private import implementations.StructuredExceptionHandling
+private import implementations.ZMQ

cpp/ql/lib/semmle/code/cpp/models/implementations/ZMQ.qll

@@ -0,0 +1,36 @@
+/**
+ * Provides implementation classes modeling the ZeroMQ networking library.
+ */
+
+import semmle.code.cpp.models.interfaces.FlowSource
+
+/**
+ * Remote flow sources.
+ */
+private class ZMQSource extends SourceModelCsv {
+  override predicate row(string row) {
+    row =
+      [
+        ";;false;zmq_recv;;;Argument[*1];remote",
+        ";;false;zmq_recvmsg;;;Argument[*1];remote",
+        ";;false;zmq_msg_recv;;;Argument[*0];remote",
+      ]
+  }
+}
+
+/**
+ * Remote flow sinks.
+ */
+private class ZMQSinks extends SinkModelCsv {
+  override predicate row(string row) {
+    row =
+      [
+        ";;false;zmq_send;;;Argument[*1];remote-sink",
+        ";;false;zmq_msg_init_data;;;Argument[*1];remote-sink",
+        ";;false;zmq_sendmsg;;;Argument[*1];remote-sink",
+        ";;false;zmq_msg_send;;;Argument[*0];remote-sink",
+      ]
+  }
+}
+
+        // TODO: flow into / through zmq_msg_data ?

cpp/ql/lib/semmle/code/cpp/security/FlowSources.qll

@@ -93,6 +93,9 @@ abstract class RemoteFlowSink extends DataFlow::Node {
   abstract string getSinkType();
 }
 
+/**
+ * A remote flow sink derived from the `RemoteFlowSinkFunction` model.
+ */
 private class RemoteParameterSink extends RemoteFlowSink {
   string sourceType;
 
@@ -106,3 +109,12 @@ private class RemoteParameterSink extends RemoteFlowSink {
 
   override string getSinkType() { result = sourceType }
 }
+
+/**
+ * A remote flow sink defined in a CSV model.
+ */
+private class RemoteFlowFromCSVSink extends RemoteFlowSink {
+  RemoteFlowFromCSVSink() { sinkNode(this, "remote-sink") }
+
+  override string getSinkType() { result = "remote flow sink" }
+}