Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*

 *  linux/net/sunrpc/gss_krb5_unseal.c

 *

 *  Adapted from MIT Kerberos 5-1.2.1 lib/gssapi/krb5/k5unseal.c

 *

 *  Copyright (c) 2000 The Regents of the University of Michigan.

 *  All rights reserved.

 *

 *  Andy Adamson   <andros@umich.edu>

 */

/*

 * Copyright 1993 by OpenVision Technologies, Inc.

 *

 * Permission to use, copy, modify, distribute, and sell this software

 * and its documentation for any purpose is hereby granted without fee,

 * provided that the above copyright notice appears in all copies and

 * that both that copyright notice and this permission notice appear in

 * supporting documentation, and that the name of OpenVision not be used

 * in advertising or publicity pertaining to distribution of the software

 * without specific, written prior permission. OpenVision makes no

 * representations about the suitability of this software for any

 * purpose.  It is provided "as is" without express or implied warranty.

 *

 * OPENVISION DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,

 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO

 * EVENT SHALL OPENVISION BE LIABLE FOR ANY SPECIAL, INDIRECT OR

 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF

 * USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR

 * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR

 * PERFORMANCE OF THIS SOFTWARE.

 */

/*

 * Copyright (C) 1998 by the FundsXpress, INC.

 *

 * 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 FundsXpress. not be used in advertising or publicity pertaining

 * to distribution of the software without specific, written prior

 * permission.  FundsXpress makes no representations about the suitability of

 * this software for any purpose.  It is provided "as is" without express

 * or implied warranty.

 *

 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR

 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED

 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.

 */

#include <linux/types.h>

#include <linux/slab.h>

#include <linux/jiffies.h>

#include <linux/sunrpc/gss_krb5.h>

#include <linux/crypto.h>

#ifdef RPC_DEBUG

# define RPCDBG_FACILITY        RPCDBG_AUTH

#endif

/* read_token is a mic token, and message_buffer is the data that the mic was

 * supposedly taken over. */

u32

gss_verify_mic_kerberos(struct gss_ctx *gss_ctx,

                struct xdr_buf *message_buffer, struct xdr_netobj *read_token)

{

        struct krb5_ctx         *ctx = gss_ctx->internal_ctx_id;

        int                     signalg;

        int                     sealalg;

        char                    cksumdata[16];

        struct xdr_netobj       md5cksum = {.len = 0, .data = cksumdata};

        s32                     now;

        int                     direction;

        s32                     seqnum;

        unsigned char           *ptr = (unsigned char *)read_token->data;

        int                     bodysize;

        dprintk("RPC:       krb5_read_token\n");

        if (g_verify_token_header(&ctx->mech_used, &bodysize, &ptr,

                                        read_token->len))

                return GSS_S_DEFECTIVE_TOKEN;

        if ((*ptr++ != ((KG_TOK_MIC_MSG>>8)&0xff)) ||

            (*ptr++ != ( KG_TOK_MIC_MSG    &0xff))   )

                return GSS_S_DEFECTIVE_TOKEN;

        /* XXX sanity-check bodysize?? */

        signalg = ptr[0] + (ptr[1] << 8);

        if (signalg != SGN_ALG_DES_MAC_MD5)

                return GSS_S_DEFECTIVE_TOKEN;

        sealalg = ptr[2] + (ptr[3] << 8);

        if (sealalg != SEAL_ALG_NONE)

                return GSS_S_DEFECTIVE_TOKEN;

        if ((ptr[4] != 0xff) || (ptr[5] != 0xff))

                return GSS_S_DEFECTIVE_TOKEN;

        if (make_checksum("md5", ptr - 2, 8, message_buffer, 0, &md5cksum))

                return GSS_S_FAILURE;

        if (krb5_encrypt(ctx->seq, NULL, md5cksum.data, md5cksum.data, 16))

                return GSS_S_FAILURE;

        if (memcmp(md5cksum.data + 8, ptr + 14, 8))

                return GSS_S_BAD_SIG;

        /* it got through unscathed.  Make sure the context is unexpired */

        now = get_seconds();

        if (now > ctx->endtime)

                return GSS_S_CONTEXT_EXPIRED;

        /* do sequencing checks */

        if (krb5_get_seq_num(ctx->seq, ptr + 14, ptr + 6, &direction, &seqnum))

                return GSS_S_FAILURE;

        if ((ctx->initiate && direction != 0xff) ||

            (!ctx->initiate && direction != 0))

                return GSS_S_BAD_SIG;

        return GSS_S_COMPLETE;

}