NAME

       gss_unwrap - API function

SYNOPSIS

       #include <gss.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 output_message_buffer, int * conf_state, gss_qop_t * qop_state);

ARGUMENTS

       OM_uint32 * minor_status
                   (Integer, modify) Mechanism specific status code.

       const gss_ctx_id_t context_handle
                   (gss_ctx_id_t, read) Identifies the context on
                     which the message arrived.

       const gss_buffer_t input_message_buffer
                   (buffer, opaque, read) Protected message.

       gss_buffer_t output_message_buffer
                   (buffer, opaque, modify) Buffer to receive
                     unwrapped message.  Storage associated with this buffer must be
                     freed by the application after use use with a call to
                     gss_release_buffer().

       int * conf_state
                   (boolean, modify, optional) Non-zero - Confidentiality
                     and integrity protection were used. Zero - Integrity service only
                     was used.  Specify NULL if not required.

       gss_qop_t * qop_state
                   (gss_qop_t, modify, optional) Quality of protection
                     provided.  Specify NULL if not required.

DESCRIPTION

       Converts a message previously protected by gss_wrap 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()  to  provide  "secure
       framing", implementations must support the wrapping and unwrapping of zero-length messages.

RETURN VALUE

       `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 duplication.

       `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.

REPORTING BUGS

       Report    bugs    to    <bug-gss@gnu.org>.     GNU    Generic     Security     Service     home     page:
       http://www.gnu.org/software/gss/ General help using GNU software: http://www.gnu.org/gethelp/

COPYRIGHT

       Copyright © 2003-2013 Simon Josefsson.
       Copying  and distribution of this file, with or without modification, are permitted in any medium without
       royalty provided the copyright notice and this notice are preserved.

SEE ALSO

       The full documentation for gss is maintained as a Texinfo manual.  If  the  info  and  gss  programs  are
       properly installed at your site, the command

              info gss

       should give you access to the complete manual.