1 /*
2 * linux/net/sunrpc/gss_krb5_seqnum.c
3 *
4 * Adapted from MIT Kerberos 5-1.2.1 lib/gssapi/krb5/util_seqnum.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 */
11
12 /*
13 * Copyright 1993 by OpenVision Technologies, Inc.
14 *
15 * Permission to use, copy, modify, distribute, and sell this software
16 * and its documentation for any purpose is hereby granted without fee,
17 * provided that the above copyright notice appears in all copies and
18 * that both that copyright notice and this permission notice appear in
19 * supporting documentation, and that the name of OpenVision not be used
20 * in advertising or publicity pertaining to distribution of the software
21 * without specific, written prior permission. OpenVision makes no
22 * representations about the suitability of this software for any
23 * purpose. It is provided "as is" without express or implied warranty.
24 *
25 * OPENVISION DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
26 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
27 * EVENT SHALL OPENVISION BE LIABLE FOR ANY SPECIAL, INDIRECT OR
28 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
29 * USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
30 * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
31 * PERFORMANCE OF THIS SOFTWARE.
32 */
33
34 #include <crypto/skcipher.h>
35 #include <linux/types.h>
36 #include <linux/sunrpc/gss_krb5.h>
37
38 #include "gss_krb5_internal.h"
39
40 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
41 # define RPCDBG_FACILITY RPCDBG_AUTH
42 #endif
43
44 s32
krb5_make_seq_num(struct krb5_ctx * kctx,struct crypto_sync_skcipher * key,int direction,u32 seqnum,unsigned char * cksum,unsigned char * buf)45 krb5_make_seq_num(struct krb5_ctx *kctx,
46 struct crypto_sync_skcipher *key,
47 int direction,
48 u32 seqnum,
49 unsigned char *cksum, unsigned char *buf)
50 {
51 unsigned char *plain;
52 s32 code;
53
54 plain = kmalloc(8, GFP_KERNEL);
55 if (!plain)
56 return -ENOMEM;
57
58 plain[0] = (unsigned char) (seqnum & 0xff);
59 plain[1] = (unsigned char) ((seqnum >> 8) & 0xff);
60 plain[2] = (unsigned char) ((seqnum >> 16) & 0xff);
61 plain[3] = (unsigned char) ((seqnum >> 24) & 0xff);
62
63 plain[4] = direction;
64 plain[5] = direction;
65 plain[6] = direction;
66 plain[7] = direction;
67
68 code = krb5_encrypt(key, cksum, plain, buf, 8);
69 kfree(plain);
70 return code;
71 }
72
73 s32
krb5_get_seq_num(struct krb5_ctx * kctx,unsigned char * cksum,unsigned char * buf,int * direction,u32 * seqnum)74 krb5_get_seq_num(struct krb5_ctx *kctx,
75 unsigned char *cksum,
76 unsigned char *buf,
77 int *direction, u32 *seqnum)
78 {
79 s32 code;
80 unsigned char *plain;
81 struct crypto_sync_skcipher *key = kctx->seq;
82
83 dprintk("RPC: krb5_get_seq_num:\n");
84
85 plain = kmalloc(8, GFP_KERNEL);
86 if (!plain)
87 return -ENOMEM;
88
89 if ((code = krb5_decrypt(key, cksum, buf, plain, 8)))
90 goto out;
91
92 if ((plain[4] != plain[5]) || (plain[4] != plain[6]) ||
93 (plain[4] != plain[7])) {
94 code = (s32)KG_BAD_SEQ;
95 goto out;
96 }
97
98 *direction = plain[4];
99
100 *seqnum = ((plain[0]) |
101 (plain[1] << 8) | (plain[2] << 16) | (plain[3] << 24));
102
103 out:
104 kfree(plain);
105 return code;
106 }
107