I've edited this question to more directly ask for the information I'm looking for.
In this callback function:
int verify_cert_chain_callback(int ok, X509_STORE_CTX *store)
I'd like to determine which SSL* or SSL_CTX* it originally came from...or was generated from. Is there a way to get that information?
I'm looking for something similar to this feature request, which would add an application-defined argument to be supplied to the callback function, but for "SSL_CTX_set_verify()"
https://github.com/openssl/openssl/issues/2929
Thanks for any suggestions.
Related
I know how I can hook functions from the IAT table, but I have a problem with APIs which were imported by calling LoadLibrary/GetProcAddress functions. I want to know exactly how someone could hook those functions. I realize that I should hook the GetProcAddress function but how can I check the parameters that were passsed to that function?
For example, consider a program which is going to include MessageBoxW via LoadLibrary/GetProcAddress, how can I hook that MessageBoxW and then check the parameters that have been passed to it?
I have searched a lot in StackOverflow and Google, but I couldn't find a step-by-step tutorial about this. So, if you have such a tutorial or article, I would be really grateful to read them.
In order to hook APIs that they are loaded into a binary dynamically with help of LoadLibrary/GetProcAddress, you should intercept return address of the GetProcAddress and name of the functions that passed to it (for example, consider a program try to load MessageBoxA in this way).
In the second step, you should save that original address of MessageBoxA API in a variable like OriginalMessageBoxA.
In the third and final step, you should return address of your modified API (HookedMessageBoxA) to the callee of the GetProcAddress so when the program try to call that address, program redirected to your function. Something like the following one:
VOID* HookedGetProcAddress(HMODULE hModule, LPCSTR lpProcName)
{
if (std::string(lpProcName).compare("MessageBoxA") == 0)
{
OMessageBoxA = (PMessageBoxA)GetProcAddress(hModule, lpProcName);
return HookedMessageBoxA;
}
else
{
return OGetProcAddress(hModule, lpProcName);
}
}
In that moment, caller will go through your HookedMessageBoxA and you can check parameters that passed to MessageBoxA. As folks said, it is kinda same like normal IAT hook with a minor changes and tricks.
source code file:https://github.com/mysql/mysql-server/blob/5.6/sql/item.cc#L5381
function:bool Item_field::fix_fields
guys,I am a c++ beginner.i am trying use GDB to debug mysql.
now,I have a question:
in this function Item_field::fix_fields(),i found a object called "context->first_name_resolution_table":
from_field= find_field_in_tables(thd, this,
context->first_name_resolution_table,
context->last_name_resolution_table,
reference,
thd->lex->use_only_table_context ?
REPORT_ALL_ERRORS :
IGNORE_EXCEPT_NON_UNIQUE,
!any_privileges, TRUE);
but I checked the function context.I could not find it。Can someone tell me that Why the context appear here.
thank you very much！
context comes from “this” object.
One of my tasks it to configure network adapters for DHCP/static IP, and the only way I found to do this is using Win32_NetworkAdapterConfiguration class.
WMI is new to me, and it seems to use it in C++ (Qt/MinGW) is not that easy, and most things I found in the WWW deal with .NET, PowerShell or VBScript. However, I already succeeded in querying information, for example the MAC address for a specific adapter.
I already read the MSDN: Calling a Provider method on MSDN, but in looking forware to WIn32_NetworkAdapterConfiguration there is one thing I don't unstand.
My IEnumWbemClassObject is the result of a SELECT * FROM Win32_NetworkAdapterConfiguration WHERE InterfaceIndex=n (n is a number, of course), and returns IWbemClassObject for the specific adapter.
How to I tell ExecMethod which instance of Win32_NetworkAdapterConiguration to use when calling the EnableDHCP()/EnableStatic() methods (in meaning of the IWbemClassObject I will recieve when i enumerate the result of my query)?
While looking for a example for passing string arrays to ExecMethod() if found this thread at CodeProject which execatly fit to my tasks. As stated in the comments above, the path of the object instance (not the class path!) must be passed to the "strObjectPath" parameter of ExecMethod.
i am new to win api ,this is what i was using in my code
SINK_ENTRY_EX(1, DIID_DWebBrowserEvents2, DISPID_DOCUMENTCOMPLETE, OnDocumentComplete)
this is perfectly working
note :
OnDocumentComplete-function pointer
DISPID_DOCUMENTCOMPLETE --display id (call the function pointed by function pointer when this event occur)
i just tried the below one which will call the event on changing status bar of browser hide or appear but its not working .
SINK_ENTRY_EX(1, DIID_DWebBrowserEvents2, DISPID_ONSTATUSBAR,OnDocumentComplete)
can any body tell me what's wrong with this?
The input parameters of the OnDocumentComplete and OnStatusBar events are different. You can't use the same function for both events.
Remy your correct i got the below link which helps me to find what function signature to be used for which event not much detail but signature of function
http://code.ohloh.net/file?fid=OqcwL0bIw3vC9ejiHfbJrKc1E_M&cid=0W4KUpSYxGo&s=&browser=Default#L0
I'm a newer to NPAPI. I come across one problem.
in my plugin, I need to return some data from C++ to JavaScript, yes,that's callback. but the callback thread and the main thread are separate threads. So I use NPN_PluginThreadAsyncCall, but the problem can not be solved also. When callback, the firefox crashed...
Can anyone help me?
the bellow codes are in the callback thread, Can anyone tell me, why it crashed?
npnfuncs->pluginthreadasynccall(instance,callBackfunc,(void*)pdata);
/////////////////////////////////////////////////////////////////////
void callBackfunc(void* arg)
{
NPObject *winobj;
npnfuncs->getvalue(instance,NPNVWindowNPObject,&winobj);
NPVariant handler;
NPIdentifier id1 = npnfuncs->getstringidentifier("MyTest".c_str());
npnfuncs->getproperty(instance, winobj, id1, &handler);
NPObject* handlerObj= NPVARIANT_TO_OBJECT(handler);
NPVariant prototype;
NPIdentifier id2 = npnfuncs->getstringidentifier("prototype");
npnfuncs->getproperty(instance, serviceHandlerObj, id2, &prototype);
NPObject* prototypeObj= NPVARIANT_TO_OBJECT(prototype);
NPIdentifier id = npnfuncs->getstringidentifier("fun".c_str());
NPVariant voidResponse;
int status=npnfuncs->invoke(instance,prototypeObj,id,args,argCount,&voidResponse);
return;
}
thanks
Best Regards
greatsea
... What is "MyTest".c_str() supposed to be? This is C++, no? c_str() is a method of a std::string class, and I don't see that being sued here, so trying to do a .c_str() on it shouldn't even compile, unless there is something going on here that I really don't understand.
Also be aware that at least Safari 5.1 has stopped supporting NPN_PluginThreadAsyncCall and different methods need to be used to make cross-thread callbacks. I don't know if other browsers have or will or not; so far it doesn't seem so.
Is there a reason you're not just using FireBreath for your plugin? It solves all of these problems for you and lets you just focus on your plugin...