Reputation: 11
I'm a C# programmer who's doing some reverse-engineering work and I'm having some trouble.
What I'm trying to do is to hook a library function in a remote process and log some data.
I've used API Monitor with some custom type and function definitions for an unknown library (libcef.dll) and I am able to intercept the functions that are defined.
I want to write my own application that hooks those functions. I've opted to use EasyHook in C++ as it seems simpler than having to marshal so much in C# using the managed EasyHook library.
EasyHook requires I define the function I want to hook with the correct function calling convention, identifier and parameters.
However, with the limited knowledge of C++ that I have, I'm able to convert the type definitions that I have for API Monitor (in an XML file) to C++ code which I can then use when defining the function I want to hook (which is cef_parse_url).
So the question is: How do I convert the below API Monitor type definitions (XML) to C++ code?
<ApiMonitor>
<Include Filename="Headers\common.h.xml" />
<Module Name="libcef.dll" CallingConvention="CDECL" OnlineHelp="Google">
<Variable Name="cef_string_t" Type="Struct">
<Field Type="wchar_t*" Name="str" />
<Field Type="size_t" Name="length" />
<Field Type="void*" Name="dtor" />
</Variable>
<Variable Name="const cef_string_t" Type="Alias" Base="cef_string_t" />
<Variable Name="cef_string_t*" Type="Pointer" Base="cef_string_t" />
<Variable Name="const cef_string_t*" Type="Pointer" Base="const cef_string_t" />
<Variable Name="cef_urlparts_t" Type="Struct">
<Field Type="cef_string_t" Name="spec" />
<Field Type="cef_string_t" Name="scheme" />
<Field Type="cef_string_t" Name="username" />
<Field Type="cef_string_t" Name="password" />
<Field Type="cef_string_t" Name="host" />
<Field Type="cef_string_t" Name="port" />
<Field Type="cef_string_t" Name="origin" />
<Field Type="cef_string_t" Name="path" />
<Field Type="cef_string_t" Name="query" />
</Variable>
<Variable Name="const cef_urlparts_t" Type="Alias" Base="cef_urlparts_t" />
<Variable Name="cef_urlparts_t*" Type="Pointer" Base="cef_urlparts_t" />
<Variable Name="const cef_urlparts_t*" Type="Pointer" Base="const cef_urlparts_t" />
<!-- Parse funcs -->
<Api Name="cef_parse_url">
<Param Type="const cef_string_t*" Name="url" />
<Param Type="cef_urlparts_t*" Name="parts" />
<Return Type="int" />
</Api>
</Module>
If someone could help me it would mean the world to me. I believe for someone who's intermediate in C++ would be able to easily be able to help me.
Thanks in advance!
Upvotes: 0
Views: 289
Reputation: 11
Alright never mind.
The answer was actually quite easy. The extra definitions which made it look so complex aren't important I found.
typedef struct _cef_string_t {
wchar_t* str;
size_t length;
void(*dtor)(wchar_t* str);
} cef_string_t;
typedef struct _cef_urlparts_t {
cef_string_t spec;
cef_string_t scheme;
cef_string_t username;
cef_string_t password;
cef_string_t host;
cef_string_t port;
cef_string_t path;
cef_string_t query;
} cef_urlparts_t;
int _cdecl cef_parse_url(const cef_string_t* url, _cef_urlparts_t* parts);
Upvotes: 1