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
|
/*
* Copyright (c) 2009,2010 Eric Faurot <eric@faurot.net>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <ctype.h>
#include <stdio.h>
#include <string.h>
#include "dnsutil.h"
size_t
dname_len(const char *dname)
{
size_t l;
l = 0;
while(dname[l])
l += dname[l] + 1;
return l;
}
size_t
dname_depth(const char *dname)
{
size_t l;
l = 0;
while(*dname) {
l += 1;
dname += *dname + 1;
}
return l;
}
const char*
dname_up(const char *dname, unsigned int n)
{
while(n--) {
if (dname[0] == '\0')
return (NULL);
dname += *dname + 1;
}
return (dname);
}
int
dname_is_in(const char *dname, const char *domain)
{
size_t l, ld;
l = dname_depth(dname);
ld = dname_depth(domain);
if (ld > l)
return (0);
dname = dname_up(dname, l - ld);
if (strcasecmp(dname, domain) == 0)
return (1);
return (0);
}
int
dname_is_reverse(const char *dname)
{
static int init = 0;
static char arpa[15];
if (init == 0) {
init = 1;
dname_from_fqdn("in-addr.arpa.", arpa, sizeof arpa);
}
return (dname_is_in(dname, arpa));
}
int
dname_is_wildcard(const char *dname)
{
return (dname[0] == 1 && dname[1] == '*');
}
int
dname_check_label(const char *s, size_t l)
{
if (l == 0 || l > 63)
return (-1);
for(l--; l; l--, s++)
if (!(isalnum(*s) || *s == '_' || *s == '-'))
return (-1);
return (0);
}
ssize_t
dname_from_fqdn(const char *str, char *dst, size_t max)
{
ssize_t res;
size_t l, n;
char *d;
res = 0;
for(;;) {
d = strchr(str, '.');
if (d == NULL)
return (-1);
l = (d - str);
if (l > 63)
return (-1);
if ((res || l) && (dname_check_label(str, l) == -1))
return (-1);
res += l + 1;
if (dst) {
*dst++ = l;
max -= 1;
n = (l > max) ? max : l;
if (n)
memmove(dst, str, n);
max -= n;
if (max == 0)
dst = NULL;
else
dst += n;
}
str = d + 1;
if (*str == '\0')
break;
}
return (res);
}
ssize_t
dname_from_sockaddr(const struct sockaddr *sa, char *dst, size_t max)
{
char buf[80];
if (sockaddr_as_fqdn(sa, buf, sizeof(buf)) == -1)
return (-1);
return dname_from_fqdn(buf, dst, max);
}
|
