xref: /freebsd/crypto/heimdal/lib/krb5/mk_safe.c (revision daf1cffce2e07931f27c6c6998652e90df6ba87e)
1 /*
2  * Copyright (c) 1997, 1998, 1999 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 1.20 1999/12/02 17:05:11 joda 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   int tmp_seq;
54   krb5_crypto crypto;
55 
56   s.pvno = 5;
57   s.msg_type = krb_safe;
58 
59   s.safe_body.user_data = *userdata;
60   krb5_us_timeofday (context, &sec, &usec);
61 
62   sec2                   = sec;
63   s.safe_body.timestamp  = &sec2;
64   usec2                  = usec2;
65   s.safe_body.usec       = &usec2;
66   if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) {
67       tmp_seq = ++auth_context->local_seqnumber;
68       s.safe_body.seq_number = &tmp_seq;
69   } else
70       s.safe_body.seq_number = NULL;
71 
72   s.safe_body.s_address = auth_context->local_address;
73   s.safe_body.r_address = auth_context->remote_address;
74 
75   s.cksum.cksumtype       = 0;
76   s.cksum.checksum.data   = NULL;
77   s.cksum.checksum.length = 0;
78 
79 
80   buf_size = length_KRB_SAFE(&s);
81   buf = malloc(buf_size + 128); /* add some for checksum */
82   if(buf == NULL)
83       return ENOMEM;
84   ret = encode_KRB_SAFE (buf + buf_size - 1, buf_size, &s, &len);
85   ret = krb5_crypto_init(context, auth_context->keyblock, 0, &crypto);
86   ret = krb5_create_checksum(context,
87 			     crypto,
88 			     KRB5_KU_KRB_SAFE_CKSUM,
89 			     buf + buf_size - len,
90 			     len,
91 			     &s.cksum);
92   krb5_crypto_destroy(context, crypto);
93   if (ret) {
94       free (buf);
95       return ret;
96   }
97 
98   buf_size = length_KRB_SAFE(&s);
99   buf = realloc(buf, buf_size);
100   if(buf == NULL)
101       return ENOMEM;
102 
103   ret = encode_KRB_SAFE (buf + buf_size - 1, buf_size, &s, &len);
104   free_Checksum (&s.cksum);
105 
106   outbuf->length = len;
107   outbuf->data   = malloc (len);
108   if (outbuf->data == NULL) {
109       free (buf);
110       return ENOMEM;
111   }
112   memcpy (outbuf->data, buf + buf_size - len, len);
113   free (buf);
114   return 0;
115 }
116