1/*
2 * Copyright (c) 1997 - 2003 Kungliga Tekniska Högskolan
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
36KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
37krb5_mk_priv(krb5_context context,
38	     krb5_auth_context auth_context,
39	     const krb5_data *userdata,
40	     krb5_data *outbuf,
41	     krb5_replay_data *outdata)
42{
43    krb5_error_code ret;
44    KRB_PRIV s;
45    EncKrbPrivPart part;
46    u_char *buf = NULL;
47    size_t buf_size;
48    size_t len = 0;
49    krb5_crypto crypto;
50    krb5_keyblock *key;
51    krb5_replay_data rdata;
52
53    if ((auth_context->flags &
54	 (KRB5_AUTH_CONTEXT_RET_TIME | KRB5_AUTH_CONTEXT_RET_SEQUENCE)) &&
55	outdata == NULL)
56	return KRB5_RC_REQUIRED; /* XXX better error, MIT returns this */
57
58    if (auth_context->local_subkey)
59	key = auth_context->local_subkey;
60    else if (auth_context->remote_subkey)
61	key = auth_context->remote_subkey;
62    else
63	key = auth_context->keyblock;
64
65    memset(&rdata, 0, sizeof(rdata));
66
67    part.user_data = *userdata;
68
69    krb5_us_timeofday (context, &rdata.timestamp, &rdata.usec);
70
71    if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_TIME) {
72	part.timestamp = &rdata.timestamp;
73	part.usec      = &rdata.usec;
74    } else {
75	part.timestamp = NULL;
76	part.usec      = NULL;
77    }
78
79    if (auth_context->flags & KRB5_AUTH_CONTEXT_RET_TIME) {
80	outdata->timestamp = rdata.timestamp;
81	outdata->usec = rdata.usec;
82    }
83
84    if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) {
85	rdata.seq = auth_context->local_seqnumber;
86	part.seq_number = &rdata.seq;
87    } else
88	part.seq_number = NULL;
89
90    if (auth_context->flags & KRB5_AUTH_CONTEXT_RET_SEQUENCE)
91	outdata->seq = auth_context->local_seqnumber;
92
93    part.s_address = auth_context->local_address;
94    part.r_address = auth_context->remote_address;
95
96    krb5_data_zero (&s.enc_part.cipher);
97
98    ASN1_MALLOC_ENCODE(EncKrbPrivPart, buf, buf_size, &part, &len, ret);
99    if (ret)
100	goto fail;
101    if (buf_size != len)
102	krb5_abortx(context, "internal error in ASN.1 encoder");
103
104    s.pvno = 5;
105    s.msg_type = krb_priv;
106    s.enc_part.etype = key->keytype;
107    s.enc_part.kvno = NULL;
108
109    ret = krb5_crypto_init(context, key, 0, &crypto);
110    if (ret) {
111	free (buf);
112	return ret;
113    }
114    ret = krb5_encrypt (context,
115			crypto,
116			KRB5_KU_KRB_PRIV,
117			buf + buf_size - len,
118			len,
119			&s.enc_part.cipher);
120    krb5_crypto_destroy(context, crypto);
121    if (ret) {
122	free(buf);
123	return ret;
124    }
125    free(buf);
126
127
128    ASN1_MALLOC_ENCODE(KRB_PRIV, buf, buf_size, &s, &len, ret);
129    if (ret)
130	goto fail;
131    if (buf_size != len)
132	krb5_abortx(context, "internal error in ASN.1 encoder");
133
134    krb5_data_free (&s.enc_part.cipher);
135
136    ret = krb5_data_copy(outbuf, buf + buf_size - len, len);
137    if (ret) {
138	krb5_set_error_message(context, ENOMEM,
139			       N_("malloc: out of memory", ""));
140	free(buf);
141	return ENOMEM;
142    }
143    free (buf);
144    if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE)
145	auth_context->local_seqnumber =
146	    (auth_context->local_seqnumber + 1) & 0xFFFFFFFF;
147    return 0;
148
149  fail:
150    free (buf);
151    krb5_data_free (&s.enc_part.cipher);
152    return ret;
153}
154