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_rep(krb5_context context,
38	    krb5_auth_context auth_context,
39	    krb5_data *outbuf)
40{
41    krb5_error_code ret;
42    AP_REP ap;
43    EncAPRepPart body;
44    u_char *buf = NULL;
45    size_t buf_size;
46    size_t len = 0;
47    krb5_crypto crypto;
48
49    ap.pvno = 5;
50    ap.msg_type = krb_ap_rep;
51
52    memset (&body, 0, sizeof(body));
53
54    body.ctime = auth_context->authenticator->ctime;
55    body.cusec = auth_context->authenticator->cusec;
56    if (auth_context->flags & KRB5_AUTH_CONTEXT_USE_SUBKEY) {
57	if (auth_context->local_subkey == NULL) {
58	    ret = krb5_auth_con_generatelocalsubkey(context,
59						    auth_context,
60						    auth_context->keyblock);
61	    if(ret) {
62		free_EncAPRepPart(&body);
63		return ret;
64	    }
65	}
66	ret = krb5_copy_keyblock(context, auth_context->local_subkey,
67				 &body.subkey);
68	if (ret) {
69	    free_EncAPRepPart(&body);
70	    krb5_set_error_message(context, ENOMEM,
71				   N_("malloc: out of memory", ""));
72	    return ENOMEM;
73	}
74    } else
75	body.subkey = NULL;
76    if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) {
77	if(auth_context->local_seqnumber == 0)
78	    krb5_generate_seq_number (context,
79				      auth_context->keyblock,
80				      &auth_context->local_seqnumber);
81	ALLOC(body.seq_number, 1);
82	if (body.seq_number == NULL) {
83	    krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
84	    free_EncAPRepPart(&body);
85	    return ENOMEM;
86	}
87	*(body.seq_number) = auth_context->local_seqnumber;
88    } else
89	body.seq_number = NULL;
90
91    ap.enc_part.etype = auth_context->keyblock->keytype;
92    ap.enc_part.kvno  = NULL;
93
94    ASN1_MALLOC_ENCODE(EncAPRepPart, buf, buf_size, &body, &len, ret);
95    free_EncAPRepPart (&body);
96    if(ret)
97	return ret;
98    if (buf_size != len)
99	krb5_abortx(context, "internal error in ASN.1 encoder");
100    ret = krb5_crypto_init(context, auth_context->keyblock,
101			   0 /* ap.enc_part.etype */, &crypto);
102    if (ret) {
103	free (buf);
104	return ret;
105    }
106    ret = krb5_encrypt (context,
107			crypto,
108			KRB5_KU_AP_REQ_ENC_PART,
109			buf + buf_size - len,
110			len,
111			&ap.enc_part.cipher);
112    krb5_crypto_destroy(context, crypto);
113    free(buf);
114    if (ret)
115	return ret;
116
117    ASN1_MALLOC_ENCODE(AP_REP, outbuf->data, outbuf->length, &ap, &len, ret);
118    if (ret == 0 && outbuf->length != len)
119	krb5_abortx(context, "internal error in ASN.1 encoder");
120    free_AP_REP (&ap);
121    return ret;
122}
123