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
|
/*++
/* NAME
/* dns_rr_to_sa 3
/* SUMMARY
/* resource record to socket address
/* SYNOPSIS
/* #include <dns.h>
/*
/* int dns_rr_to_sa(rr, port, sa, sa_length)
/* DNS_RR *rr;
/* unsigned port;
/* struct sockaddr *sa;
/* SOCKADDR_SIZE *sa_length;
/* DESCRIPTION
/* dns_rr_to_sa() converts the address in a DNS resource record into
/* a socket address of the corresponding type.
/*
/* Arguments:
/* .IP rr
/* DNS resource record pointer.
/* .IP port
/* TCP or UDP port, network byte order.
/* .IP sa
/* Socket address pointer.
/* .IP sa_length
/* On input, the available socket address storage space.
/* On output, the amount of space actually used.
/* DIAGNOSTICS
/* The result is non-zero in case of problems, with the
/* error type returned via the errno variable.
/* LICENSE
/* .ad
/* .fi
/* The Secure Mailer license must be distributed with this software.
/* AUTHOR(S)
/* Wietse Venema
/* IBM T.J. Watson Research
/* P.O. Box 704
/* Yorktown Heights, NY 10598, USA
/*--*/
/* System libraries. */
#include <sys_defs.h>
#include <errno.h>
/* Utility library. */
#include <msg.h>
/* DNS library. */
#include <dns.h>
/* dns_rr_to_sa - resource record to socket address */
int dns_rr_to_sa(DNS_RR *rr, unsigned port, struct sockaddr *sa,
SOCKADDR_SIZE *sa_length)
{
SOCKADDR_SIZE sock_addr_len;
if (rr->type == T_A) {
if (rr->data_len != sizeof(SOCK_ADDR_IN_ADDR(sa))) {
errno = EINVAL;
return (-1);
} else if ((sock_addr_len = sizeof(*SOCK_ADDR_IN_PTR(sa))) > *sa_length) {
errno = ENOSPC;
return (-1);
} else {
memset((void *) SOCK_ADDR_IN_PTR(sa), 0, sock_addr_len);
SOCK_ADDR_IN_FAMILY(sa) = AF_INET;
SOCK_ADDR_IN_PORT(sa) = port;
SOCK_ADDR_IN_ADDR(sa) = IN_ADDR(rr->data);
#ifdef HAS_SA_LEN
sa->sa_len = sock_addr_len;
#endif
*sa_length = sock_addr_len;
return (0);
}
#ifdef HAS_IPV6
} else if (rr->type == T_AAAA) {
if (rr->data_len != sizeof(SOCK_ADDR_IN6_ADDR(sa))) {
errno = EINVAL;
return (-1);
} else if ((sock_addr_len = sizeof(*SOCK_ADDR_IN6_PTR(sa))) > *sa_length) {
errno = ENOSPC;
return (-1);
} else {
memset((void *) SOCK_ADDR_IN6_PTR(sa), 0, sock_addr_len);
SOCK_ADDR_IN6_FAMILY(sa) = AF_INET6;
SOCK_ADDR_IN6_PORT(sa) = port;
SOCK_ADDR_IN6_ADDR(sa) = IN6_ADDR(rr->data);
#ifdef HAS_SA_LEN
sa->sa_len = sock_addr_len;
#endif
*sa_length = sock_addr_len;
return (0);
}
#endif
} else {
errno = EAFNOSUPPORT;
return (-1);
}
}
/*
* Stand-alone test program.
*/
#ifdef TEST
#include <stdlib.h>
#include <stringops.h>
#include <vstream.h>
#include <myaddrinfo.h>
static const char *myname;
static NORETURN usage(void)
{
msg_fatal("usage: %s dnsaddrtype hostname portnumber", myname);
}
int main(int argc, char **argv)
{
DNS_RR *rr;
MAI_HOSTADDR_STR hostaddr;
MAI_SERVPORT_STR portnum;
struct sockaddr_storage ss;
struct sockaddr *sa = (struct sockaddr *) &ss;
SOCKADDR_SIZE sa_length = sizeof(ss);
VSTRING *why;
int type;
int port;
myname = argv[0];
if (argc < 4)
usage();
why = vstring_alloc(1);
while (*++argv) {
if (argv[1] == 0 || argv[2] == 0)
usage();
if ((type = dns_type(argv[0])) == 0)
usage();
if (!alldig(argv[2]) || (port = atoi(argv[2])) > 65535)
usage();
if (dns_lookup(argv[1], type, 0, &rr, (VSTRING *) 0, why) != DNS_OK)
msg_fatal("%s: %s", argv[1], vstring_str(why));
sa_length = sizeof(ss);
if (dns_rr_to_sa(rr, htons(port), sa, &sa_length) != 0)
msg_fatal("dns_rr_to_sa: %m");
SOCKADDR_TO_HOSTADDR(sa, sa_length, &hostaddr, &portnum, 0);
vstream_printf("%s %s -> %s %s\n",
argv[1], argv[2], hostaddr.buf, portnum.buf);
vstream_fflush(VSTREAM_OUT);
argv += 2;
dns_rr_free(rr);
}
vstring_free(why);
return (0);
}
#endif
|
