1 /* $NetBSD: mk_rep.c,v 1.2 2017/01/28 21:31:49 christos Exp $ */
2
3 /*
4 * Copyright (c) 1997 - 2003 Kungliga Tekniska Högskolan
5 * (Royal Institute of Technology, Stockholm, Sweden).
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 *
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * 3. Neither the name of the Institute nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 #include "krb5_locl.h"
37
38 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_mk_rep(krb5_context context,krb5_auth_context auth_context,krb5_data * outbuf)39 krb5_mk_rep(krb5_context context,
40 krb5_auth_context auth_context,
41 krb5_data *outbuf)
42 {
43 krb5_error_code ret;
44 AP_REP ap;
45 EncAPRepPart body;
46 u_char *buf = NULL;
47 size_t buf_size;
48 size_t len = 0;
49 krb5_crypto crypto;
50
51 ap.pvno = 5;
52 ap.msg_type = krb_ap_rep;
53
54 memset (&body, 0, sizeof(body));
55
56 body.ctime = auth_context->authenticator->ctime;
57 body.cusec = auth_context->authenticator->cusec;
58 if (auth_context->flags & KRB5_AUTH_CONTEXT_USE_SUBKEY) {
59 if (auth_context->local_subkey == NULL) {
60 ret = krb5_auth_con_generatelocalsubkey(context,
61 auth_context,
62 auth_context->keyblock);
63 if(ret) {
64 free_EncAPRepPart(&body);
65 return ret;
66 }
67 }
68 ret = krb5_copy_keyblock(context, auth_context->local_subkey,
69 &body.subkey);
70 if (ret) {
71 free_EncAPRepPart(&body);
72 return krb5_enomem(context);
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 free_EncAPRepPart(&body);
84 return krb5_enomem(context);
85 }
86 *(body.seq_number) = auth_context->local_seqnumber;
87 } else
88 body.seq_number = NULL;
89
90 ap.enc_part.etype = auth_context->keyblock->keytype;
91 ap.enc_part.kvno = NULL;
92
93 ASN1_MALLOC_ENCODE(EncAPRepPart, buf, buf_size, &body, &len, ret);
94 free_EncAPRepPart (&body);
95 if(ret)
96 return ret;
97 if (buf_size != len)
98 krb5_abortx(context, "internal error in ASN.1 encoder");
99 ret = krb5_crypto_init(context, auth_context->keyblock,
100 0 /* ap.enc_part.etype */, &crypto);
101 if (ret) {
102 free (buf);
103 return ret;
104 }
105 ret = krb5_encrypt (context,
106 crypto,
107 KRB5_KU_AP_REQ_ENC_PART,
108 buf + buf_size - len,
109 len,
110 &ap.enc_part.cipher);
111 krb5_crypto_destroy(context, crypto);
112 free(buf);
113 if (ret)
114 return ret;
115
116 ASN1_MALLOC_ENCODE(AP_REP, outbuf->data, outbuf->length, &ap, &len, ret);
117 if (ret == 0 && outbuf->length != len)
118 krb5_abortx(context, "internal error in ASN.1 encoder");
119 free_AP_REP (&ap);
120 return ret;
121 }
122