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1/*
2 * This file is part of DisOrder.
3 * Copyright (C) 2004 Richard Kettlewell
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
18 * USA
19 */
20/** @file lib/addr.c Socket address support */
21
22#include <config.h>
23#include "types.h"
24
25#include <stdio.h>
26#include <string.h>
27#include <sys/types.h>
28#include <sys/socket.h>
29#include <netinet/in.h>
30#include <netdb.h>
31
32#include "log.h"
33#include "printf.h"
34#include "configuration.h"
35#include "addr.h"
36
37/** @brief Convert a pair of strings to an address
38 * @param a Pointer to string list
39 * @param pref Hints structure for getaddrinfo, or NULL
40 * @param namep Where to store address description, or NULL
41 * @return Address info structure or NULL on error
42 *
43 * This converts one or two strings into an address specification suitable
44 * for passing to socket(), bind() etc.
45 *
46 * If there is only one string then it is assumed to be the service
47 * name (port number). If there are two then the first is the host
48 * name and the second the service name.
49 *
50 * @p namep is used to return a description of the address suitable
51 * for use in log messages.
52 *
53 * If an error occurs a message is logged and a null pointer returned.
54 */
55struct addrinfo *get_address(const struct stringlist *a,
56 const struct addrinfo *pref,
57 char **namep) {
58 struct addrinfo *res;
59 char *name;
60 int rc;
61
62 switch(a->n) {
63 case 1:
64 byte_xasprintf(&name, "host * service %s", a->s[0]);
65 if((rc = getaddrinfo(0, a->s[0], pref, &res))) {
66 error(0, "getaddrinfo %s: %s", a->s[0], gai_strerror(rc));
67 return 0;
68 }
69 break;
70 case 2:
71 byte_xasprintf(&name, "host %s service %s", a->s[0], a->s[1]);
72 if((rc = getaddrinfo(a->s[0], a->s[1], pref, &res))) {
73 error(0, "getaddrinfo %s %s: %s", a->s[0], a->s[1], gai_strerror(rc));
74 return 0;
75 }
76 break;
77 default:
78 error(0, "invalid network address specification (n=%d)", a->n);
79 return 0;
80 }
81 if(!res || (pref && res->ai_socktype != pref->ai_socktype)) {
82 error(0, "getaddrinfo didn't give us a suitable socket address");
83 if(res)
84 freeaddrinfo(res);
85 return 0;
86 }
87 if(namep)
88 *namep = name;
89 return res;
90}
91
92/** @brief Comparison function for address information
93 *
94 * Suitable for qsort().
95 */
96int addrinfocmp(const struct addrinfo *a,
97 const struct addrinfo *b) {
98 const struct sockaddr_in *ina, *inb;
99 const struct sockaddr_in6 *in6a, *in6b;
100
101 if(a->ai_family != b->ai_family) return a->ai_family - b->ai_family;
102 if(a->ai_socktype != b->ai_socktype) return a->ai_socktype - b->ai_socktype;
103 if(a->ai_protocol != b->ai_protocol) return a->ai_protocol - b->ai_protocol;
104 switch(a->ai_protocol) {
105 case PF_INET:
106 ina = (const struct sockaddr_in *)a->ai_addr;
107 inb = (const struct sockaddr_in *)b->ai_addr;
108 if(ina->sin_port != inb->sin_port) return ina->sin_port - inb->sin_port;
109 return ina->sin_addr.s_addr - inb->sin_addr.s_addr;
110 break;
111 case PF_INET6:
112 in6a = (const struct sockaddr_in6 *)a->ai_addr;
113 in6b = (const struct sockaddr_in6 *)b->ai_addr;
114 if(in6a->sin6_port != in6b->sin6_port)
115 return in6a->sin6_port - in6b->sin6_port;
116 return memcmp(&in6a->sin6_addr, &in6b->sin6_addr,
117 sizeof (struct in6_addr));
118 default:
119 error(0, "unsupported protocol family %d", a->ai_protocol);
120 return memcmp(a->ai_addr, b->ai_addr, a->ai_addrlen); /* kludge */
121 }
122}
123
124/*
125Local Variables:
126c-basic-offset:2
127comment-column:40
128End:
129*/