1 /*
2 * Copyright2001 by the Massachusetts Institute of Technology.
3 * Copyright 1993 by OpenVision Technologies, Inc.
4 *
5 * Permission to use, copy, modify, distribute, and sell this software
6 * and its documentation for any purpose is hereby granted without fee,
7 * provided that the above copyright notice appears in all copies and
8 * that both that copyright notice and this permission notice appear in
9 * supporting documentation, and that the name of OpenVision not be used
10 * in advertising or publicity pertaining to distribution of the software
11 * without specific, written prior permission. OpenVision makes no
12 * representations about the suitability of this software for any
13 * purpose. It is provided "as is" without express or implied warranty.
14 *
15 * OPENVISION DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
16 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
17 * EVENT SHALL OPENVISION BE LIABLE FOR ANY SPECIAL, INDIRECT OR
18 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
19 * USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
20 * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
21 * PERFORMANCE OF THIS SOFTWARE.
22 */
23
24 #include "gssapiP_krb5.h"
25 #include "k5-int.h"
26
27 /*
28 * $Id: util_seqnum.c 15007 2002-11-15 16:12:20Z epeisach $
29 */
30
31 krb5_error_code
kg_make_seq_num(context,key,direction,seqnum,cksum,buf)32 kg_make_seq_num(context, key, direction, seqnum, cksum, buf)
33 krb5_context context;
34 krb5_keyblock *key;
35 int direction;
36 krb5_ui_4 seqnum;
37 unsigned char *cksum;
38 unsigned char *buf;
39 {
40 unsigned char plain[8];
41
42 plain[4] = direction;
43 plain[5] = direction;
44 plain[6] = direction;
45 plain[7] = direction;
46 if (key->enctype == ENCTYPE_ARCFOUR_HMAC ) {
47 /* Yes, Microsoft used big-endian sequence number.*/
48 plain[0] = (seqnum>>24) & 0xff;
49 plain[1] = (seqnum>>16) & 0xff;
50 plain[2] = (seqnum>>8) & 0xff;
51 plain[3] = seqnum & 0xff;
52 return kg_arcfour_docrypt (context, key, 0,
53 cksum, 8,
54 &plain[0], 8,
55 buf);
56
57 }
58
59 plain[0] = (unsigned char) (seqnum&0xff);
60 plain[1] = (unsigned char) ((seqnum>>8)&0xff);
61 plain[2] = (unsigned char) ((seqnum>>16)&0xff);
62 plain[3] = (unsigned char) ((seqnum>>24)&0xff);
63
64 return(kg_encrypt(context, key, KG_USAGE_SEQ, cksum, plain, buf, 8));
65 }
66
kg_get_seq_num(context,key,cksum,buf,direction,seqnum)67 krb5_error_code kg_get_seq_num(context, key, cksum, buf, direction, seqnum)
68 krb5_context context;
69 krb5_keyblock *key;
70 unsigned char *cksum;
71 unsigned char *buf;
72 int *direction;
73 krb5_ui_4 *seqnum;
74 {
75 krb5_error_code code;
76 unsigned char plain[8];
77
78 if (key->enctype == ENCTYPE_ARCFOUR_HMAC) {
79 code = kg_arcfour_docrypt (context, key, 0,
80 cksum, 8,
81 buf, 8,
82 plain);
83 } else {
84 code = kg_decrypt(context, key, KG_USAGE_SEQ, cksum, buf, plain, 8);
85 }
86 if (code)
87 return(code);
88
89 if ((plain[4] != plain[5]) ||
90 (plain[4] != plain[6]) ||
91 (plain[4] != plain[7]))
92 return((krb5_error_code) KG_BAD_SEQ);
93
94 *direction = plain[4];
95 if (key->enctype == ENCTYPE_ARCFOUR_HMAC) {
96 *seqnum = (plain[3]|(plain[2]<<8) | (plain[1]<<16)| (plain[0]<<24));
97 } else {
98 *seqnum = ((plain[0]) |
99 (plain[1]<<8) |
100 (plain[2]<<16) |
101 (plain[3]<<24));
102 }
103
104 return(0);
105 }
106