Is it possible to pass references to structures containing array of references as from C# to C dll?

Hi everyone! I am trying to write a C dll plugin for my Unity project that performs some algorithmic calculation based on a set of structured data. As an example, I have a few structures defined in C++ below to explain what I mean.

 struct typeC
 {
    int units;
 };
 
 struct typeB
 {
     char* name;
     int index;
     float speed;
     typeC** pArrayofC;
     int NumOfC;
 
 };
 
 struct typeA
 {
     int NumObj;
     typeB** pArrayOfB;
     int NumOfB;
 
 };

As you can see from the above structs, typeA contains an array of pointers to typeB objects and a corresponding number indicating the size of the array. Struct typeB and typeC has similar relationship. This forms some of sort of database with chain referencing in C++.

The problem is I want the Unity C# class to be the owner of these objects (fully in charge of creation and deletion of them) and simply pass a reference to a single typeA object to the C dll such that it can read through the whole "database" and perform its algorithm but I have no idea how to write the C# definitions and code for these structs. I have read abit about marshalling structures to/fro C#/C and have seen some examples but couldn't find any examples similar to my case.

Is it possible to do what I have described? Can anyone give me some help/tips/advice on this?