1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
|
/*
* Copyright (C) 2013 Tobias Brunner
* Copyright (C) 2012 Reto Guadagnini
* HSR Hochschule fuer Technik Rapperswil
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*/
/*
* Copyright (C) 2013 Ruslan Marchenko
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#define _GNU_SOURCE
#include <stdio.h>
#include <string.h>
#include "dnscert_cred.h"
#include "dnscert.h"
typedef struct private_dnscert_cred_t private_dnscert_cred_t;
/**
* Private data of an dnscert_cred_t object
*/
struct private_dnscert_cred_t {
/**
* Public part
*/
dnscert_cred_t public;
/**
* DNS resolver
*/
resolver_t *res;
};
/**
* enumerator over certificates
*/
typedef struct {
/** implements enumerator interface */
enumerator_t public;
/** inner enumerator (enumerates CERT resource records) */
enumerator_t *inner;
/** response of the DNS resolver which contains the CERTs */
resolver_response_t *response;
/** most recently enumerated certificate */
certificate_t *cert;
} cert_enumerator_t;
METHOD(enumerator_t, cert_enumerator_enumerate, bool,
cert_enumerator_t *this, va_list args)
{
certificate_t **cert;
dnscert_t *cur_crt;
rr_t *cur_rr;
chunk_t certificate;
VA_ARGS_VGET(args, cert);
/* Get the next supported CERT using the inner enumerator. */
while (this->inner->enumerate(this->inner, &cur_rr))
{
cur_crt = dnscert_create_frm_rr(cur_rr);
if (!cur_crt)
{
DBG1(DBG_CFG, " failed to parse CERT RR, skipping");
continue;
}
if (cur_crt->get_cert_type(cur_crt) != DNSCERT_TYPE_PKIX &&
cur_crt->get_cert_type(cur_crt) != DNSCERT_TYPE_PGP)
{
DBG1(DBG_CFG, " unsupported CERT type [%d], skipping",
cur_crt->get_cert_type(cur_crt));
cur_crt->destroy(cur_crt);
continue;
}
/* Try to parse PEM certificate container. Both x509 and PGP should
* presumably come as PEM encoded certs. */
certificate = cur_crt->get_certificate(cur_crt);
DESTROY_IF(this->cert);
this->cert = lib->creds->create(lib->creds, CRED_CERTIFICATE, CERT_ANY,
BUILD_BLOB_PEM, certificate,
BUILD_END);
cur_crt->destroy(cur_crt);
if (!this->cert)
{
DBG1(DBG_CFG, " unable to parse certificate, skipping");
continue;
}
*cert = this->cert;
return TRUE;
}
return FALSE;
}
METHOD(enumerator_t, cert_enumerator_destroy, void,
cert_enumerator_t *this)
{
DESTROY_IF(this->cert);
this->inner->destroy(this->inner);
this->response->destroy(this->response);
free(this);
}
METHOD(credential_set_t, create_cert_enumerator, enumerator_t*,
private_dnscert_cred_t *this, certificate_type_t cert, key_type_t key,
identification_t *id, bool trusted)
{
resolver_response_t *response;
cert_enumerator_t *e;
char *fqdn;
if (!id || id->get_type(id) != ID_FQDN)
{
return enumerator_create_empty();
}
/* query the DNS for the required CERT RRs */
if (asprintf(&fqdn, "%Y", id) <= 0)
{
DBG1(DBG_CFG, "failed to determine FQDN to retrieve CERT RRs");
return enumerator_create_empty();
}
DBG1(DBG_CFG, "performing a DNS query for CERT RRs of '%s'", fqdn);
response = this->res->query(this->res, fqdn, RR_CLASS_IN, RR_TYPE_CERT);
if (!response)
{
DBG1(DBG_CFG, " query for CERT RRs failed");
free(fqdn);
return enumerator_create_empty();
}
free(fqdn);
if (!response->has_data(response) ||
!response->query_name_exist(response))
{
DBG1(DBG_CFG, " unable to retrieve CERT RRs from the DNS");
response->destroy(response);
return enumerator_create_empty();
}
if (response->get_security_state(response) != SECURE)
{
DBG1(DBG_CFG, " DNSSEC state of CERT RRs is not secure");
response->destroy(response);
return enumerator_create_empty();
}
INIT(e,
.public = {
.enumerate = enumerator_enumerate_default,
.venumerate = _cert_enumerator_enumerate,
.destroy = _cert_enumerator_destroy,
},
.inner = response->get_rr_set(response)->create_rr_enumerator(
response->get_rr_set(response)),
.response = response
);
return &e->public;
}
METHOD(dnscert_cred_t, destroy, void,
private_dnscert_cred_t *this)
{
this->res->destroy(this->res);
free(this);
}
/**
* Described in header.
*/
dnscert_cred_t *dnscert_cred_create(resolver_t *res)
{
private_dnscert_cred_t *this;
INIT(this,
.public = {
.set = {
.create_private_enumerator = (void*)return_null,
.create_cert_enumerator = _create_cert_enumerator,
.create_shared_enumerator = (void*)return_null,
.create_cdp_enumerator = (void*)return_null,
.cache_cert = (void*)nop,
},
.destroy = _destroy,
},
.res = res,
);
return &this->public;
}
|
