LXR linux/net/sunrpc/auth_gss/gss_krb5

   1/*
   2 *  linux/net/sunrpc/gss_krb5_seal.c
   3 *
   4 *  Adapted from MIT Kerberos 5-1.2.1 lib/gssapi/krb5/k5seal.c
   5 *
   6 *  Copyright (c) 2000 The Regents of the University of Michigan.
   7 *  All rights reserved.
   8 *
   9 *  Andy Adamson        <andros@umich.edu>
  10 *  J. Bruce Fields     <bfields@umich.edu>
  11 */
  12
  13/*
  14 * Copyright 1993 by OpenVision Technologies, Inc.
  15 *
  16 * Permission to use, copy, modify, distribute, and sell this software
  17 * and its documentation for any purpose is hereby granted without fee,
  18 * provided that the above copyright notice appears in all copies and
  19 * that both that copyright notice and this permission notice appear in
  20 * supporting documentation, and that the name of OpenVision not be used
  21 * in advertising or publicity pertaining to distribution of the software
  22 * without specific, written prior permission. OpenVision makes no
  23 * representations about the suitability of this software for any
  24 * purpose.  It is provided "as is" without express or implied warranty.
  25 *
  26 * OPENVISION DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  27 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  28 * EVENT SHALL OPENVISION BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  29 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
  30 * USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
  31 * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  32 * PERFORMANCE OF THIS SOFTWARE.
  33 */
  34
  35/*
  36 * Copyright (C) 1998 by the FundsXpress, INC.
  37 *
  38 * All rights reserved.
  39 *
  40 * Export of this software from the United States of America may require
  41 * a specific license from the United States Government.  It is the
  42 * responsibility of any person or organization contemplating export to
  43 * obtain such a license before exporting.
  44 *
  45 * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
  46 * distribute this software and its documentation for any purpose and
  47 * without fee is hereby granted, provided that the above copyright
  48 * notice appear in all copies and that both that copyright notice and
  49 * this permission notice appear in supporting documentation, and that
  50 * the name of FundsXpress. not be used in advertising or publicity pertaining
  51 * to distribution of the software without specific, written prior
  52 * permission.  FundsXpress makes no representations about the suitability of
  53 * this software for any purpose.  It is provided "as is" without express
  54 * or implied warranty.
  55 *
  56 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
  57 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  58 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  59 */
  60
  61#include <linux/types.h>
  62#include <linux/slab.h>
  63#include <linux/jiffies.h>
  64#include <linux/sunrpc/gss_krb5.h>
  65#include <linux/random.h>
  66#include <linux/crypto.h>
  67
  68#ifdef RPC_DEBUG
  69# define RPCDBG_FACILITY        RPCDBG_AUTH
  70#endif
  71
  72DEFINE_SPINLOCK(krb5_seq_lock);
  73
  74u32
  75gss_get_mic_kerberos(struct gss_ctx *gss_ctx, struct xdr_buf *text,
  76                struct xdr_netobj *token)
  77{
  78        struct krb5_ctx         *ctx = gss_ctx->internal_ctx_id;
  79        char                    cksumdata[16];
  80        struct xdr_netobj       md5cksum = {.len = 0, .data = cksumdata};
  81        unsigned char           *ptr, *msg_start;
  82        s32                     now;
  83        u32                     seq_send;
  84
  85        dprintk("RPC:       gss_krb5_seal\n");
  86        BUG_ON(ctx == NULL);
  87
  88        now = get_seconds();
  89
  90        token->len = g_token_size(&ctx->mech_used, GSS_KRB5_TOK_HDR_LEN + 8);
  91
  92        ptr = token->data;
  93        g_make_token_header(&ctx->mech_used, GSS_KRB5_TOK_HDR_LEN + 8, &ptr);
  94
  95        /* ptr now at header described in rfc 1964, section 1.2.1: */
  96        ptr[0] = (unsigned char) ((KG_TOK_MIC_MSG >> 8) & 0xff);
  97        ptr[1] = (unsigned char) (KG_TOK_MIC_MSG & 0xff);
  98
  99        msg_start = ptr + GSS_KRB5_TOK_HDR_LEN + 8;
 100
 101        *(__be16 *)(ptr + 2) = htons(SGN_ALG_DES_MAC_MD5);
 102        memset(ptr + 4, 0xff, 4);
 103
 104        if (make_checksum("md5", ptr, 8, text, 0, &md5cksum))
 105                return GSS_S_FAILURE;
 106
 107        if (krb5_encrypt(ctx->seq, NULL, md5cksum.data,
 108                          md5cksum.data, md5cksum.len))
 109                return GSS_S_FAILURE;
 110
 111        memcpy(ptr + GSS_KRB5_TOK_HDR_LEN, md5cksum.data + md5cksum.len - 8, 8);
 112
 113        spin_lock(&krb5_seq_lock);
 114        seq_send = ctx->seq_send++;
 115        spin_unlock(&krb5_seq_lock);
 116
 117        if (krb5_make_seq_num(ctx->seq, ctx->initiate ? 0 : 0xff,
 118                              seq_send, ptr + GSS_KRB5_TOK_HDR_LEN,
 119                              ptr + 8))
 120                return GSS_S_FAILURE;
 121
 122        return (ctx->endtime < now) ? GSS_S_CONTEXT_EXPIRED : GSS_S_COMPLETE;
 123}
 124