xref: /freebsd/sbin/ipf/libipf/alist_new.c (revision f81cdf24ba5436367377f7c8e8f51f6df2a75ca7)
1 /*
2  * Copyright (C) 2012 by Darren Reed.
3  *
4  * See the IPFILTER.LICENCE file for details on licencing.
5  *
6  * $Id: alist_new.c,v 1.5.2.2 2012/07/22 08:04:24 darren_r Exp $
7  */
8 
9 #include "ipf.h"
10 #include <ctype.h>
11 
12 alist_t *
13 alist_new(int family, char *host)
14 {
15 	int a, b, c, d, bits;
16 	char *slash;
17 	alist_t *al;
18 	u_int mask;
19 
20 	if (family == AF_UNSPEC) {
21 		if (strchr(host, ':') != NULL)
22 			family = AF_INET6;
23 		else
24 			family = AF_INET;
25 	}
26 	if (family != AF_INET && family != AF_INET6)
27 		return (NULL);
28 
29 	al = calloc(1, sizeof(*al));
30 	if (al == NULL) {
31 		fprintf(stderr, "alist_new out of memory\n");
32 		return (NULL);
33 	}
34 
35 	while (ISSPACE(*host))
36 		host++;
37 
38 	if (*host == '!') {
39 		al->al_not = 1;
40 		host++;
41 		while (ISSPACE(*host))
42 			host++;
43 	}
44 
45 	bits = -1;
46 	slash = strchr(host, '/');
47 	if (slash != NULL) {
48 		*slash = '\0';
49 		bits = atoi(slash + 1);
50 	}
51 
52 	if (family == AF_INET) {
53 		if (bits > 32)
54 			goto bad;
55 
56 		a = b = c = d = -1;
57 		sscanf(host, "%d.%d.%d.%d", &a, &b, &c, &d);
58 
59 		if (bits > 0 && bits < 33) {
60 			mask = 0xffffffff << (32 - bits);
61 		} else if (b == -1) {
62 			mask = 0xff000000;
63 			b = c = d = 0;
64 		} else if (c == -1) {
65 			mask = 0xffff0000;
66 			c = d = 0;
67 		} else if (d == -1) {
68 			mask = 0xffffff00;
69 			d = 0;
70 		} else {
71 			mask = 0xffffffff;
72 		}
73 		al->al_mask = htonl(mask);
74 	} else {
75 		if (bits > 128)
76 			goto bad;
77 		fill6bits(bits, al->al_i6mask.i6);
78 	}
79 
80 	if (gethost(family, host, &al->al_i6addr) == -1) {
81 		if (slash != NULL)
82 			*slash = '/';
83 		fprintf(stderr, "Cannot parse hostname\n");
84 		goto bad;
85 	}
86 	al->al_family = family;
87 	if (slash != NULL)
88 		*slash = '/';
89 	return (al);
90 bad:
91 	free(al);
92 	return (NULL);
93 }
94