ISecurityProperty::GetOriginalCallerSID method (comsvcs.h)

Retrieves the security identifier of the base process that initiated the call sequence from which the current method was called.

The preferred way to obtain information about the original caller is to use the ISecurityCallContext interface.

Syntax

HRESULT GetOriginalCallerSID(
  [out] PSID *pSID
);

Parameters

[out] pSID

A reference to the security ID of the base process that initiated the call sequence from which the current method was called.

Return value

This method can return the standard return values E_INVALIDARG, E_OUTOFMEMORY, E_UNEXPECTED, and E_FAIL, as well as the following values.

Return code	Description
S_OK	The security ID of the base process that originated the call into the current object is returned in the parameter pSid.
CONTEXT_E_NOCONTEXT	The current object does not have a context associated with it because either the component was not imported into an application or the object was not created with one of the COM+ CreateInstance methods.

Remarks

You use the GetOriginalCallerSID method to determine the security ID of the original process that initiated the call sequence from which the current method was called, not the originator (or creator) of the process. Although a pointer to an object can be passed through a series of servers and users, GetOriginalCallerSID always returns the first server and user of the process, even if that user was not the original creator of the object. The following scenario illustrates the functionality of the GetOriginalCallerSID method.

1. Base Process 1, running on Server A as user A, creates Object X, on Server B, running as user B.
2. Base Process 1 passes its reference on Object X to Base Process 2, running on Server D as user D.
3. Base Process 2 uses that reference to call into Object X.
4. Object X calls into Object Y, running on Server C. If Object Y then calls GetOriginalCallerSID, the security ID of user D is returned, not user A, who originally created the object.

Note  Usually, an object's original caller is the same process as its original creator. The only situation in which the original caller and the original creator would be different is one in which the original creator passes a reference to another process and the other process initiates the call sequence (as in the preceding example).

 

The path to the original caller is broken if any object along the chain was created by some means other than IObjectContext::CreateInstance or ITransactionContext::CreateInstance. For example, if Base Process 1 uses CoCreateInstance to create Object X, when Object Y calls GetOriginalCallerSID the security ID it gets back is the security ID of user B, not user D. This is because the call sequence is traced back through the objects' context and COM+ can create a context only for an object that is created with either IObjectContext::CreateInstance or ITransactionContext::CreateInstance.

You must call ReleaseSID on a security ID when you finish using it.

Requirements

Requirement	Value
Minimum supported client	Windows 2000 Professional [desktop apps only]
Minimum supported server	Windows 2000 Server [desktop apps only]
Target Platform	Windows
Header	comsvcs.h

See also

ISecurityProperty