1 /* This file is part of the Project Athena Zephyr Notification System.
2 * It contains source for the ZMakeAuthentication function.
3 *
4 * Created by: Robert French
5 *
6 * Copyright (c) 1987 by the Massachusetts Institute of Technology.
7 * For copying and distribution information, see the file
8 * "mit-copyright.h".
9 */
10
11 #include "internal.h"
12
13 #ifndef ERROR_TABLE_BASE_krb
14 #define ERROR_TABLE_BASE_krb (39525376L)
15 #endif
16
17 #ifdef ZEPHYR_USES_KERBEROS
18 #ifdef WIN32
19
20 #else
21 #include <krb_err.h>
22 #endif
23 static long last_authent_time = 0L;
24 static KTEXT_ST last_authent;
25 #endif
26
27 #if 0
28 Code_t ZResetAuthentication () {
29 #ifdef ZEPHYR_USES_KERBEROS
30 last_authent_time = 0L;
31 #endif
32 return ZERR_NONE;
33 }
34 #endif
35
ZMakeAuthentication(notice,buffer,buffer_len,len)36 Code_t ZMakeAuthentication(notice, buffer, buffer_len, len)
37 register ZNotice_t *notice;
38 char *buffer;
39 int buffer_len;
40 int *len;
41 {
42 #ifdef ZEPHYR_USES_KERBEROS
43 int result;
44 time_t now;
45 KTEXT_ST authent;
46 char *cstart, *cend;
47 ZChecksum_t checksum;
48 CREDENTIALS cred;
49 extern unsigned long des_quad_cksum();
50
51 now = time(0);
52 if (last_authent_time == 0 || (now - last_authent_time > 120)) {
53 result = krb_mk_req(&authent, SERVER_SERVICE,
54 SERVER_INSTANCE, __Zephyr_realm, 0);
55 if (result != MK_AP_OK) {
56 last_authent_time = 0;
57 return (result+ERROR_TABLE_BASE_krb);
58 }
59 last_authent_time = now;
60 last_authent = authent;
61 }
62 else {
63 authent = last_authent;
64 }
65 notice->z_auth = 1;
66 notice->z_authent_len = authent.length;
67 notice->z_ascii_authent = (char *)malloc((unsigned)authent.length*3);
68 /* zero length authent is an error, so malloc(0) is not a problem */
69 if (!notice->z_ascii_authent)
70 return (ENOMEM);
71 if ((result = ZMakeAscii(notice->z_ascii_authent,
72 authent.length*3,
73 authent.dat,
74 authent.length)) != ZERR_NONE) {
75 free(notice->z_ascii_authent);
76 return (result);
77 }
78 result = Z_FormatRawHeader(notice, buffer, buffer_len, len, &cstart,
79 &cend);
80 free(notice->z_ascii_authent);
81 notice->z_authent_len = 0;
82 if (result)
83 return(result);
84
85 /* Compute a checksum over the header and message. */
86 if ((result = krb_get_cred(SERVER_SERVICE, SERVER_INSTANCE,
87 __Zephyr_realm, &cred)) != 0)
88 return result;
89 checksum = des_quad_cksum(buffer, NULL, cstart - buffer, 0, (C_Block *)cred.session);
90 checksum ^= des_quad_cksum(cend, NULL, buffer + *len - cend, 0,
91 (C_Block *)cred.session);
92 checksum ^= des_quad_cksum(notice->z_message, NULL, notice->z_message_len,
93 0, (C_Block *)cred.session);
94 notice->z_checksum = checksum;
95 ZMakeAscii32(cstart, buffer + buffer_len - cstart, checksum);
96
97 return (ZERR_NONE);
98 #else
99 notice->z_checksum = 0;
100 notice->z_auth = 1;
101 notice->z_authent_len = 0;
102 notice->z_ascii_authent = "";
103 return (Z_FormatRawHeader(notice, buffer, buffer_len, len, NULL, NULL));
104 #endif
105 }
106