- attach a cryptographic message
cc [ flag... ] file... -lgss [ library... ] #include <gssapi/gssapi.h> OM_uint32 gss_wrap(OM_uint32 *minor_status, const gss_ctx_id_t context_handle, int conf_req_flag, gss_qop_t qop_req, const gss_buffer_t input_message_buffer, int *conf_state, gss_buffer_t output_message_buffer);
The gss_wrap() function attaches a cryptographic MIC and optionally encrypts the specified input_message. The output_message contains both the MIC and the message. The qop_req parameter allows a choice between several cryptographic algorithms, if supported by the chosen mechanism.
Since some application-level protocols may wish to use tokens emitted by gss_wrap() to provide secure framing, the GSS-API supports the wrapping of zero-length messages.
The parameter descriptions for gss_wrap() follow:
The status code returned by the underlying mechanism.
Identifies the context on which the message will be sent.
If the value of conf_req_flag is non-zero, both confidentiality and integrity services are requested. If the value is zero, then only integrity service is requested.
Specifies the required quality of protection. A mechanism-specific default may be requested by setting qop_req to GSS_C_QOP_DEFAULT. If an unsupported protection strength is requested, gss_wrap() will return a major_status of GSS_S_BAD_QOP.
The message to be protected.
If the value of conf_state is non-zero, confidentiality, data origin authentication, and integrity services have been applied. If the value is zero, then integrity services have been applied. Specify NULL if this parameter is not required.
The buffer to receive the protected message. Storage associated with this message must be freed by the application after use with a call to gss_release_buffer(3GSS).
gss_wrap() may return the following status codes:
The context has already expired.
The context_handle parameter did not identify a valid context.
The specified QOP is not supported by the mechanism.
The underlying mechanism detected an error for which no specific GSS status code is defined. The mechanism-specific status code reported by means of the minor_status parameter details the error condition.
See attributes(5) for descriptions of the following attributes: