xref: /freebsd/crypto/heimdal/lib/krb5/mk_safe.c (revision 1e413cf93298b5b97441a21d9a50fdcd0ee9945e)
1 /*
2  * Copyright (c) 1997 - 2002 Kungliga Tekniska H�gskolan
3  * (Royal Institute of Technology, Stockholm, Sweden).
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * 3. Neither the name of the Institute nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include <krb5_locl.h>
35 
36 RCSID("$Id: mk_safe.c,v 1.28.4.1 2004/03/07 12:46:43 lha Exp $");
37 
38 krb5_error_code
39 krb5_mk_safe(krb5_context context,
40 	     krb5_auth_context auth_context,
41 	     const krb5_data *userdata,
42 	     krb5_data *outbuf,
43 	     /*krb5_replay_data*/ void *outdata)
44 {
45   krb5_error_code ret;
46   KRB_SAFE s;
47   int32_t sec, usec;
48   KerberosTime sec2;
49   int usec2;
50   u_char *buf = NULL;
51   size_t buf_size;
52   size_t len;
53   u_int32_t tmp_seq;
54   krb5_crypto crypto;
55   krb5_keyblock *key;
56 
57   if (auth_context->local_subkey)
58       key = auth_context->local_subkey;
59   else if (auth_context->remote_subkey)
60       key = auth_context->remote_subkey;
61   else
62       key = auth_context->keyblock;
63 
64   s.pvno = 5;
65   s.msg_type = krb_safe;
66 
67   s.safe_body.user_data = *userdata;
68   krb5_us_timeofday (context, &sec, &usec);
69 
70   sec2                   = sec;
71   s.safe_body.timestamp  = &sec2;
72   usec2                  = usec;
73   s.safe_body.usec       = &usec2;
74   if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) {
75       tmp_seq = auth_context->local_seqnumber;
76       s.safe_body.seq_number = &tmp_seq;
77   } else
78       s.safe_body.seq_number = NULL;
79 
80   s.safe_body.s_address = auth_context->local_address;
81   s.safe_body.r_address = auth_context->remote_address;
82 
83   s.cksum.cksumtype       = 0;
84   s.cksum.checksum.data   = NULL;
85   s.cksum.checksum.length = 0;
86 
87   ASN1_MALLOC_ENCODE(KRB_SAFE, buf, buf_size, &s, &len, ret);
88   if (ret)
89       return ret;
90   if(buf_size != len)
91       krb5_abortx(context, "internal error in ASN.1 encoder");
92   ret = krb5_crypto_init(context, key, 0, &crypto);
93   if (ret) {
94       free (buf);
95       return ret;
96   }
97   ret = krb5_create_checksum(context,
98 			     crypto,
99 			     KRB5_KU_KRB_SAFE_CKSUM,
100 			     0,
101 			     buf,
102 			     len,
103 			     &s.cksum);
104   krb5_crypto_destroy(context, crypto);
105   if (ret) {
106       free (buf);
107       return ret;
108   }
109 
110   free(buf);
111   ASN1_MALLOC_ENCODE(KRB_SAFE, buf, buf_size, &s, &len, ret);
112   free_Checksum (&s.cksum);
113   if(ret)
114       return ret;
115   if(buf_size != len)
116       krb5_abortx(context, "internal error in ASN.1 encoder");
117 
118   outbuf->length = len;
119   outbuf->data   = buf;
120   if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE)
121       auth_context->local_seqnumber =
122 	  (auth_context->local_seqnumber + 1) & 0xFFFFFFFF;
123   return 0;
124 }
125