gss_unwrap(3GSS)				  Generic Security Services API Library Functions				  gss_unwrap(3GSS)

NAME

       gss_unwrap - verify a message with attached cryptographic message

SYNOPSIS

       cc -flag ...  file ...-lgss [library ...]
       #include <gssapi/gssapi.h>

       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 out-
       put_message_buffer, int *conf_state, gss_qop_t *qop_state);

DESCRIPTION

       The gss_unwrap() function converts a message previously protected by gss_wrap(3GSS) back to a usable form, verifying the embedded MIC.  The
       conf_state  parameter  indicates  whether  the message was encrypted; the qop_state parameter indicates the strength of protection that was
       used to provide the confidentiality and integrity services.

       Since some application-level protocols may wish to use tokens emitted by gss_wrap(3GSS) to provide secure framing, the GSS-API supports the
       wrapping and unwrapping of zero-length messages.

PARAMETERS

       The parameter descriptions for gss_unwrap() follow:

       minor_status	       The status code returned by the underlying mechanism.

       context_handle	       Identifies the context on which the message arrived.

       input_message_buffer    The message to be protected.

       output_message_buffer   The  buffer  to receive the unwrapped message. Storage associated with this buffer must be freed by the application
			       after use with a call to gss_release_buffer(3GSS).

       conf_state	       If the value of conf_state is non-zero, then confidentiality and integrity protection were used. If  the  value	is
			       zero, only integrity service was used. Specify NULL if this parameter is not required.

       qop_state	       Specifies the quality of protection provided. Specify NULL if this parameter is not required.

ERRORS

       gss_unwrap() may return the following status codes:

       GSS_S_COMPLETE		       Successful completion.

       GSS_S_DEFECTIVE_TOKEN	       The token failed consistency checks.

       GSS_S_BAD_SIG		       The MIC was incorrect.

       GSS_S_DUPLICATE_TOKEN	       The token was valid, and contained a correct MIC for the message, but it had already been processed.

       GSS_S_OLD_TOKEN		       The  token  was valid, and contained a correct MIC for the message, but it is too old to check for duplica-
				       tion.

       GSS_S_UNSEQ_TOKEN	       The token was valid, and contained a correct MIC for the message, but has been verified out of sequence;  a
				       later token has already been received.

       GSS_S_GAP_TOKEN		       The token was valid, and contained a correct MIC for the message, but has been verified out of sequence; an
				       earlier expected token has not yet been received.

       GSS_S_CONTEXT_EXPIRED	       The context has already expired.

       GSS_S_NO_CONTEXT 	       The context_handle parameter did not identify a valid context.

       GSS_S_FAILURE		       The underlying mechanism detected an error for which no specific GSS status code is  defined.   The  mecha-
				       nism-specific status code reported by means of the minor_status parameter details the error condition.

ATTRIBUTES

       See attributes(5)  for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWgss (32-bit)		   |
       +-----------------------------+-----------------------------+
       |			     |SUNWgssx (64-bit) 	   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       gss_release_buffer(3GSS), gss_wrap(3GSS), attributes(5)

       Solaris Security for Developers Guide

SunOS 5.10							    15 Jan 2003 						  gss_unwrap(3GSS)