1/*
2  Linux DNS client library implementation
3
4  Copyright (C) 2006 Krishna Ganugapati <krishnag@centeris.com>
5  Copyright (C) 2006 Gerald Carter <jerry@samba.org>
6
7     ** NOTE! The following LGPL license applies to the libaddns
8     ** library. This does NOT imply that all of Samba is released
9     ** under the LGPL
10
11  This library is free software; you can redistribute it and/or
12  modify it under the terms of the GNU Lesser General Public
13  License as published by the Free Software Foundation; either
14  version 2.1 of the License, or (at your option) any later version.
15
16  This library is distributed in the hope that it will be useful,
17  but WITHOUT ANY WARRANTY; without even the implied warranty of
18  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
19  Lesser General Public License for more details.
20
21  You should have received a copy of the GNU Lesser General Public
22  License along with this library; if not, write to the Free Software
23  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
24  02110-1301  USA
25*/
26
27#include "dns.h"
28#include <ctype.h>
29
30static DNS_ERROR LabelList( TALLOC_CTX *mem_ctx,
31			    const char *name,
32			    struct dns_domain_label **presult )
33{
34	struct dns_domain_label *result;
35	const char *dot;
36
37	for (dot = name; *dot != '\0'; dot += 1) {
38		char c = *dot;
39
40		if (c == '.')
41			break;
42
43		if (c == '-') continue;
44		if ((c >= 'a') && (c <= 'z')) continue;
45		if ((c >= 'A') && (c <= 'Z')) continue;
46		if ((c >= '0') && (c <= '9')) continue;
47
48		return ERROR_DNS_INVALID_NAME;
49	}
50
51	if ((dot - name) > 63) {
52		/*
53		 * DNS labels can only be 63 chars long
54		 */
55		return ERROR_DNS_INVALID_NAME;
56	}
57
58	if (!(result = TALLOC_ZERO_P(mem_ctx, struct dns_domain_label))) {
59		return ERROR_DNS_NO_MEMORY;
60	}
61
62	if (*dot == '\0') {
63		/*
64		 * No dot around, so this is the last component
65		 */
66
67		if (!(result->label = talloc_strdup(result, name))) {
68			TALLOC_FREE(result);
69			return ERROR_DNS_NO_MEMORY;
70		}
71		result->len = strlen(result->label);
72		*presult = result;
73		return ERROR_DNS_SUCCESS;
74	}
75
76	if (dot[1] == '.') {
77		/*
78		 * Two dots in a row, reject
79		 */
80
81		TALLOC_FREE(result);
82		return ERROR_DNS_INVALID_NAME;
83	}
84
85	if (dot[1] != '\0') {
86		/*
87		 * Something follows, get the rest
88		 */
89
90		DNS_ERROR err = LabelList(result, dot+1, &result->next);
91
92		if (!ERR_DNS_IS_OK(err)) {
93			TALLOC_FREE(result);
94			return err;
95		}
96	}
97
98	result->len = (dot - name);
99
100	if (!(result->label = talloc_strndup(result, name, result->len))) {
101		TALLOC_FREE(result);
102		return ERROR_DNS_NO_MEMORY;
103	}
104
105	*presult = result;
106	return ERROR_DNS_SUCCESS;
107}
108
109DNS_ERROR dns_domain_name_from_string( TALLOC_CTX *mem_ctx,
110				       const char *pszDomainName,
111				       struct dns_domain_name **presult )
112{
113	struct dns_domain_name *result;
114	DNS_ERROR err;
115
116	if (!(result = talloc(mem_ctx, struct dns_domain_name))) {
117		return ERROR_DNS_NO_MEMORY;
118	}
119
120	err = LabelList( result, pszDomainName, &result->pLabelList );
121	if (!ERR_DNS_IS_OK(err)) {
122		TALLOC_FREE(result);
123		return err;
124	}
125
126	*presult = result;
127	return ERROR_DNS_SUCCESS;
128}
129
130/*********************************************************************
131*********************************************************************/
132
133char *dns_generate_keyname( TALLOC_CTX *mem_ctx )
134{
135	char *result = NULL;
136#if defined(WITH_DNS_UPDATES)
137
138	uuid_t uuid;
139
140	/*
141	 * uuid_unparse gives 36 bytes plus '\0'
142	 */
143	if (!(result = TALLOC_ARRAY(mem_ctx, char, 37))) {
144		return NULL;
145	}
146
147	uuid_generate( uuid );
148	uuid_unparse( uuid, result );
149
150#endif
151
152	return result;
153}
154