'\" te

.\" Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved.

.TH gss_unwrap 3GSS "22 Aug 2011" "SunOS 5.12" "Generic Security Services API Library Functions"

.SH NAME

gss_unwrap \- verify a message with attached cryptographic message

.SH SYNOPSIS

.LP

.nf

\fBcc\fR [ \fIflag\fR... ] \fIfile\fR... \fB-lgss\fR  [ \fIlibrary\fR... ] 

#include <gssapi/gssapi.h>

\fBOM_uint32\fR \fBgss_unwrap\fR(\fBOM_uint32 *\fR\fIminor_status\fR,

     \fBconst gss_ctx_id_t\fR \fIcontext_handle\fR,

     \fBconst gss_buffer_t\fR \fIinput_message_buffer\fR,

     \fBgss_buffer_t\fR \fIoutput_message_buffer\fR, \fBint *\fR\fIconf_state\fR,

     \fBgss_qop_t *\fR\fIqop_state\fR);

.fi

.SH DESCRIPTION

.sp

.LP

The \fBgss_unwrap()\fR function converts a message previously protected by \fBgss_wrap\fR(3GSS) back to a usable form, verifying the embedded \fBMIC\fR. The \fIconf_state\fR parameter indicates whether the message was encrypted; the \fIqop_state\fR parameter indicates the strength of protection that was used to provide the confidentiality and integrity services.

.sp

.LP

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

.SH PARAMETERS

.sp

.LP

The parameter descriptions for \fBgss_unwrap()\fR follow:

.sp

.ne 2

.mk

.na

\fB\fIminor_status\fR\fR

.ad

.RS 25n

.rt  

The status code returned by the underlying mechanism.

.RE

.sp

.ne 2

.mk

.na

\fB\fIcontext_handle\fR\fR

.ad

.RS 25n

.rt  

Identifies the context on which the message arrived.

.RE

.sp

.ne 2

.mk

.na

\fB\fIinput_message_buffer\fR\fR

.ad

.RS 25n

.rt  

The message to be protected.

.RE

.sp

.ne 2

.mk

.na

\fB\fIoutput_message_buffer\fR\fR

.ad

.RS 25n

.rt  

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

.RE

.sp

.ne 2

.mk

.na

\fB\fIconf_state\fR\fR

.ad

.RS 25n

.rt  

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

.RE

.sp

.ne 2

.mk

.na

\fB\fIqop_state\fR\fR

.ad

.RS 25n

.rt  

Specifies the quality of protection provided. Specify \fBNULL\fR if this parameter is not required.

.RE

.SH ERRORS

.sp

.LP

\fBgss_unwrap()\fR may return the following status codes:

.sp

.ne 2

.mk

.na

\fB\fBGSS_S_COMPLETE\fR\fR

.ad

.RS 25n

.rt  

Successful completion.

.RE

.sp

.ne 2

.mk

.na

\fB\fBGSS_S_DEFECTIVE_TOKEN\fR\fR

.ad

.RS 25n

.rt  

The token failed consistency checks.

.RE

.sp

.ne 2

.mk

.na

\fB\fBGSS_S_BAD_SIG\fR\fR

.ad

.RS 25n

.rt  

The \fBMIC\fR was incorrect.

.RE

.sp

.ne 2

.mk

.na

\fB\fBGSS_S_DUPLICATE_TOKEN\fR\fR

.ad

.RS 25n

.rt  

The token was valid, and contained a correct \fBMIC\fR for the message, but it had already been processed.

.RE

.sp

.ne 2

.mk

.na

\fB\fBGSS_S_OLD_TOKEN\fR\fR

.ad

.RS 25n

.rt  

The token was valid, and contained a correct \fBMIC\fR for the message, but it is too old to check for duplication.

.RE

.sp

.ne 2

.mk

.na

\fB\fBGSS_S_UNSEQ_TOKEN\fR\fR

.ad

.RS 25n

.rt  

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

.RE

.sp

.ne 2

.mk

.na

\fB\fBGSS_S_GAP_TOKEN\fR\fR

.ad

.RS 25n

.rt  

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

.RE

.sp

.ne 2

.mk

.na

\fB\fBGSS_S_CONTEXT_EXPIRED\fR\fR

.ad

.RS 25n

.rt  

The context has already expired.

.RE

.sp

.ne 2

.mk

.na

\fB\fBGSS_S_NO_CONTEXT\fR\fR

.ad

.RS 25n

.rt  

The \fIcontext_handle\fR parameter did not identify a valid context.

.RE

.sp

.ne 2

.mk

.na

\fB\fBGSS_S_FAILURE\fR\fR

.ad

.RS 25n

.rt  

The underlying mechanism detected an error for which no specific \fBGSS\fR status code is defined.  The mechanism-specific status code reported by means of the \fIminor_status\fR parameter details the error condition.

.RE

.SH ATTRIBUTES

.sp

.LP

See \fBattributes\fR(5)  for descriptions of the following attributes:

.sp

.sp

.TS

tab() box;

cw(2.75i) |cw(2.75i) 

lw(2.75i) |lw(2.75i) 

.

ATTRIBUTE TYPEATTRIBUTE VALUE

_

MT-LevelSafe

.TE

.SH SEE ALSO

.sp

.LP

\fBgss_release_buffer\fR(3GSS), \fBgss_wrap\fR(3GSS), \fBattributes\fR(5)

.sp

.LP