xref: /netbsd-src/external/bsd/ipf/dist/lib/alist_new.c (revision 13885a665959c62f13a82b3caedf986eaa17aa31)
1 /*	$NetBSD: alist_new.c,v 1.2 2012/07/22 14:27:36 darrenr Exp $	*/
2 
3 /*
4  * Copyright (C) 2012 by Darren Reed.
5  *
6  * See the IPFILTER.LICENCE file for details on licencing.
7  *
8  * Id: alist_new.c,v 1.1.1.2 2012/07/22 13:44:38 darrenr Exp $
9  */
10 
11 #include "ipf.h"
12 #include <ctype.h>
13 
14 alist_t *
alist_new(int family,char * host)15 alist_new(int family, char *host)
16 {
17 	int a, b, c, d, bits;
18 	char *slash;
19 	alist_t *al;
20 	u_int mask;
21 
22 	if (family == AF_UNSPEC) {
23 		if (strchr(host, ':') != NULL)
24 			family = AF_INET6;
25 		else
26 			family = AF_INET;
27 	}
28 	if (family != AF_INET && family != AF_INET6)
29 		return NULL;
30 
31 	al = calloc(1, sizeof(*al));
32 	if (al == NULL) {
33 		fprintf(stderr, "alist_new out of memory\n");
34 		return NULL;
35 	}
36 
37 	while (ISSPACE(*host))
38 		host++;
39 
40 	if (*host == '!') {
41 		al->al_not = 1;
42 		host++;
43 		while (ISSPACE(*host))
44 			host++;
45 	}
46 
47 	bits = -1;
48 	slash = strchr(host, '/');
49 	if (slash != NULL) {
50 		*slash = '\0';
51 		bits = atoi(slash + 1);
52 	}
53 
54 	if (family == AF_INET) {
55 		if (bits > 32)
56 			goto bad;
57 
58 		a = b = c = d = -1;
59 		sscanf(host, "%d.%d.%d.%d", &a, &b, &c, &d);
60 
61 		if (bits > 0 && bits < 33) {
62 			mask = 0xffffffff << (32 - bits);
63 		} else if (b == -1) {
64 			mask = 0xff000000;
65 			b = c = d = 0;
66 		} else if (c == -1) {
67 			mask = 0xffff0000;
68 			c = d = 0;
69 		} else if (d == -1) {
70 			mask = 0xffffff00;
71 			d = 0;
72 		} else {
73 			mask = 0xffffffff;
74 		}
75 		al->al_mask = htonl(mask);
76 	} else {
77 		if (bits > 128)
78 			goto bad;
79 		fill6bits(bits, al->al_i6mask.i6);
80 	}
81 
82 	if (gethost(family, host, &al->al_i6addr) == -1) {
83 		if (slash != NULL)
84 			*slash = '/';
85 		fprintf(stderr, "Cannot parse hostname\n");
86 		goto bad;
87 	}
88 	al->al_family = family;
89 	if (slash != NULL)
90 		*slash = '/';
91 	return al;
92 bad:
93 	free(al);
94 	return NULL;
95 }
96