/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/* lib/gssapi/krb5/import_sec_context.c - Internalize the security context */
/*
 * Copyright 1995,2004,2007,2008 by the Massachusetts Institute of Technology.
 * All Rights Reserved.
 *
 * Export of this software from the United States of America may
 *   require a specific license from the United States Government.
 *   It is the responsibility of any person or organization contemplating
 *   export to obtain such a license before exporting.
 *
 * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
 * distribute this software and its documentation for any purpose and
 * without fee is hereby granted, provided that the above copyright
 * notice appear in all copies and that both that copyright notice and
 * this permission notice appear in supporting documentation, and that
 * the name of M.I.T. not be used in advertising or publicity pertaining
 * to distribution of the software without specific, written prior
 * permission.  Furthermore if you modify this software you must label
 * your software as modified software and not distribute it in such a
 * fashion that it might be confused with the original M.I.T. software.
 * M.I.T. makes no representations about the suitability of
 * this software for any purpose.  It is provided "as is" without express
 * or implied warranty.
 */

#include "gssapiP_krb5.h"
/* for serialization initialization functions */
#include "k5-int.h"

/*
 * Fix up the OID of the mechanism so that uses the static version of
 * the OID if possible.
 */
gss_OID krb5_gss_convert_static_mech_oid(gss_OID oid)
{
    const gss_OID_desc      *p;
    OM_uint32               minor_status;

    for (p = krb5_gss_oid_array; p->length; p++) {
        if ((oid->length == p->length) &&
            (memcmp(oid->elements, p->elements, p->length) == 0)) {
            generic_gss_release_oid(&minor_status, &oid);
            return (gss_OID) p;
        }
    }
    return oid;
}

OM_uint32 KRB5_CALLCONV
krb5_gss_import_sec_context(OM_uint32 *minor_status,
                            gss_buffer_t interprocess_token,
                            gss_ctx_id_t *context_handle)
{
    krb5_context        context;
    krb5_error_code     kret = 0;
    size_t              blen;
    krb5_gss_ctx_id_t   ctx;
    krb5_octet          *ibp;

    /* This is a bit screwy.  We create a krb5 context because we need
       one when calling the serialization code.  However, one of the
       objects we're unpacking is a krb5 context, so when we finish,
       we can throw this one away.  */
    kret = krb5_gss_init_context(&context);
    if (kret) {
        *minor_status = kret;
        return GSS_S_FAILURE;
    }

    /* Assume a tragic failure */
    ctx = (krb5_gss_ctx_id_t) NULL;
    *minor_status = 0;

    /* Internalize the context */
    ibp = (krb5_octet *) interprocess_token->value;
    blen = (size_t) interprocess_token->length;
    kret = kg_ctx_internalize(context, &ctx, &ibp, &blen);
    if (kret) {
        *minor_status = (OM_uint32) kret;
        save_error_info(*minor_status, context);
        krb5_free_context(context);
        return(GSS_S_FAILURE);
    }
    krb5_free_context(context);

    ctx->mech_used = krb5_gss_convert_static_mech_oid(ctx->mech_used);

    *context_handle = (gss_ctx_id_t) ctx;

    *minor_status = 0;
    return (GSS_S_COMPLETE);
}