RpcBindingInqAuthClientA function (rpcdce.h)

A server application calls the RpcBindingInqAuthClient function to obtain the principal name or privilege attributes of the authenticated client that made the remote procedure call.

Syntax

RPC_STATUS RpcBindingInqAuthClientA(
  RPC_BINDING_HANDLE ClientBinding,
  RPC_AUTHZ_HANDLE   *Privs,
  RPC_CSTR           *ServerPrincName,
  unsigned long      *AuthnLevel,
  unsigned long      *AuthnSvc,
  unsigned long      *AuthzSvc
);

Parameters

ClientBinding

Client binding handle of the client that made the remote procedure call. This value can be zero. See Remarks.

Privs

Returns a pointer to a handle to the privileged information for the client application that made the remote procedure call on the ClientBinding binding handle. For ncalrpc calls, Privs contains a string with the client's principal name.

The data referenced by this parameter is read-only and should not be modified by the server application. If the server wants to preserve any of the returned data, the server must copy the data into server-allocated memory.

The data that the Privs parameter points to comes directly from the SSP. Therefore, the format of the data is specific to the SSP. For more information on SSPs, see Security Support Providers (SSPs).

ServerPrincName

Returns a pointer to a pointer to the server principal name specified by the server application that called the RpcServerRegisterAuthInfo function. The content of the returned name and its syntax are defined by the authentication service in use. For the SCHANNEL SSP, the principal name is in Microsoft-standard (msstd) format. For further information on msstd format, see Principal Names.

Specify a null value to prevent RpcBindingInqAuthClient from returning the ServerPrincName parameter. In this case, the application does not call the RpcStringFree function.

AuthnLevel

Returns a pointer set to the level of authentication requested by the client application that made the remote procedure call on the ClientBinding binding handle.

Specify a null value to prevent RpcBindingInqAuthClient from returning the AuthnLevel parameter.

AuthnSvc

Returns a pointer set to the authentication service requested by the client application that made the remote procedure call on the ClientBinding binding handle. For a list of the RPC-supported authentication levels, see Authentication-Level Constants.

Specify a null value to prevent RpcBindingInqAuthClient from returning the AuthnSvc parameter.

AuthzSvc

Returns a pointer set to the authorization service requested by the client application that made the remote procedure call on the ClientBinding binding handle.

Specify a null value to prevent RpcBindingInqAuthClient from returning the AuthzSvc parameter. This parameter is not used by the RPC_C_AUTHN_WINNT authentication service. The returned value will always be RPC_C_AUTHZ_NONE.

Return value

Value Meaning
RPC_S_OK
The call succeeded.
RPC_S_INVALID_BINDING
The binding handle was invalid.
RPC_S_WRONG_KIND_OF_BINDING
This was the wrong kind of binding for the operation.
RPC_S_BINDING_HAS_NO_AUTH
Binding has no authentication information.
 
Note  For a list of valid error codes, see RPC Return Values.
 

Remarks

A server application calls the RpcBindingInqAuthClient function to obtain the principal name or privilege attributes of the authenticated client that made the remote procedure call. In addition, RpcBindingInqAuthClient returns the authentication service, authentication level, and server principal name specified by the client. The server can use the returned data for authorization purposes.

The RPC run-time library allocates memory for the returned ServerPrincName parameter. The application is responsible for calling the RpcStringFree function for the returned argument string.

For synchronous RPC calls, the server application can use zero as the value for the ClientBinding parameter. Using zero retrieves the authentication and authorization information from the currently executing remote procedure call.

Note

The rpcdce.h header defines RpcBindingInqAuthClient as an alias that automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant. Mixing usage of the encoding-neutral alias with code that is not encoding-neutral can lead to mismatches that result in compilation or runtime errors. For more information, see Conventions for Function Prototypes.

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 rpcdce.h (include Rpc.h)
Library Rpcrt4.lib
DLL Rpcrt4.dll

See also

RpcBindingSetAuthInfo

RpcStringFree