gss_unwrap()

gss_unwrap() looks like this:

OM_uint32 gss_unwrap (
OM_uint32          *minor_status,
const gss_ctx_id_t context_handle,
const gss_buffer_t input_message_buffer,
gss_buffer_t       output_message_buffer,
int                *conf_state
gss_qop_t          *qop_state)

minor_status

The status code returned by the underlying security mechanism.

context_handle

The context under which this message will be sent.

input_message_buffer

The wrapped message. This argument must be in the form of a gss_buffer_desc object; see Strings and Similar Data. Must be freed up with gss_release_buffer() when you have finished with it.

output_message_buffer

The buffer for the unwrapped wrapped message. After the application is done with the unwrapped message, it must release this buffer with gss_release_buffer(). This argument is also a gss_buffer_desc object.

conf_state

A flag that indicates whether confidentiality was applied or not. If non-zero, then confidentiality, message origin authentication, and integrity services were applied. If zero, only message-origin authentication and integrity were applied. Specify NULL if not required.

qop_state

The QOP (Quality of Protection) used. This is the cryptographic algorithm used in generating the MIC and doing the encryption. Specify NULL if not required.

gss_unwrap() returns GSS_S_COMPLETE if the message was successfully unwrapped. If it cannot verify the message against its MIC, it returns GSS_S_BAD_SIG.