Commit | Line | Data |
---|---|---|
07554ccd MW |
1 | /* |
2 | * addrfam.c | |
3 | * - address-family specific code | |
4 | */ | |
5 | /* | |
6 | * This file is part of adns, which is | |
7 | * Copyright (C) 1997-2000,2003,2006 Ian Jackson | |
8 | * Copyright (C) 1999-2000,2003,2006 Tony Finch | |
9 | * Copyright (C) 1991 Massachusetts Institute of Technology | |
10 | * (See the file INSTALL for full details.) | |
11 | * | |
12 | * This program is free software; you can redistribute it and/or modify | |
13 | * it under the terms of the GNU General Public License as published by | |
14 | * the Free Software Foundation; either version 2, or (at your option) | |
15 | * any later version. | |
16 | * | |
17 | * This program is distributed in the hope that it will be useful, | |
18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
20 | * GNU General Public License for more details. | |
21 | * | |
22 | * You should have received a copy of the GNU General Public License | |
23 | * along with this program; if not, write to the Free Software Foundation, | |
24 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
25 | */ | |
26 | ||
27 | #include <stdlib.h> | |
28 | #include <errno.h> | |
29 | #include <limits.h> | |
30 | #include <unistd.h> | |
31 | ||
32 | #include <sys/types.h> | |
33 | #include <sys/socket.h> | |
34 | #include <netinet/in.h> | |
35 | #include <arpa/inet.h> | |
36 | ||
37 | #include "internal.h" | |
38 | ||
39 | /* | |
40 | * General address-family operations. | |
41 | */ | |
42 | ||
43 | #define SIN(sa) ((struct sockaddr_in *)(sa)) | |
44 | #define CSIN(sa) ((const struct sockaddr_in *)(sa)) | |
45 | ||
46 | #define SIN6(sa) ((struct sockaddr_in6 *)(sa)) | |
47 | #define CSIN6(sa) ((const struct sockaddr_in6 *)(sa)) | |
48 | ||
49 | /* This gadget (thanks, Richard Kettlewell) makes sure that we handle the | |
50 | * same set of address families in each switch. */ | |
51 | #define AF_CASES(pre) \ | |
52 | case AF_INET: goto pre##_inet; \ | |
53 | case AF_INET6: goto pre##_inet6 | |
54 | ||
55 | static void unknown_af(int af) { | |
56 | fprintf(stderr, "ADNS INTERNAL: unknown address family %d\n", af); | |
57 | abort(); | |
58 | } | |
59 | ||
60 | #define IN6_ADDR_EQUALP(a, b) \ | |
61 | (!memcmp((a).s6_addr, (b).s6_addr, sizeof((a).s6_addr))) | |
62 | ||
63 | int adns__genaddr_equal_p(int af, const union gen_addr *a, | |
64 | int bf, const void *b) { | |
65 | const union gen_addr *bb= b; | |
66 | if (af != bf) return 0; | |
67 | switch (af) { | |
68 | AF_CASES(af); | |
69 | af_inet: return a->v4.s_addr == bb->v4.s_addr; | |
70 | af_inet6: return IN6_ADDR_EQUALP(a->v6, bb->v6); | |
71 | default: unknown_af(af); return -1; | |
72 | } | |
73 | } | |
74 | ||
75 | int adns__sockaddr_equal_p(const struct sockaddr *sa, | |
76 | const struct sockaddr *sb) { | |
77 | if (sa->sa_family != sb->sa_family) return 0; | |
78 | switch (sa->sa_family) { | |
79 | AF_CASES(af); | |
80 | af_inet: { | |
81 | const struct sockaddr_in *sina= CSIN(sa), *sinb= CSIN(sb); | |
82 | return (sina->sin_addr.s_addr == sinb->sin_addr.s_addr && | |
83 | sina->sin_port == sinb->sin_port); | |
84 | } | |
85 | af_inet6: { | |
86 | /* Don't check the flowlabel. That's apparently useful for routing | |
87 | * performance, but doesn't affect the address in any important | |
88 | * respect. */ | |
89 | const struct sockaddr_in6 *sin6a= CSIN6(sa), *sin6b= CSIN6(sb); | |
90 | return (IN6_ADDR_EQUALP(sin6a->sin6_addr, sin6b->sin6_addr) && | |
91 | sin6a->sin6_port == sin6b->sin6_port && | |
92 | sin6a->sin6_scope_id == sin6b->sin6_scope_id); | |
93 | } | |
94 | default: | |
95 | unknown_af(sa->sa_family); | |
96 | return -1; | |
97 | } | |
98 | } | |
99 | ||
100 | int adns__addr_width(int af) { | |
101 | switch (af) { | |
102 | AF_CASES(af); | |
103 | af_inet: return 32; | |
104 | af_inet6: return 128; | |
105 | default: unknown_af(af); return -1; | |
106 | } | |
107 | } | |
108 | ||
109 | void adns__prefix_mask(int af, int len, union gen_addr *mask_r) { | |
110 | switch (af) { | |
111 | AF_CASES(af); | |
112 | af_inet: | |
113 | assert(len <= 32); | |
114 | mask_r->v4.s_addr= htonl(!len ? 0 : 0xffffffff << (32-len)); | |
115 | break; | |
116 | af_inet6: { | |
117 | int i= len/8, j= len%8; | |
118 | unsigned char *m= mask_r->v6.s6_addr; | |
119 | assert(len <= 128); | |
120 | memset(m, 0xff, i); | |
121 | if (j) m[i++]= (0xff << (8-j)) & 0xff; | |
122 | memset(m+i, 0, 16-i); | |
123 | } break; | |
124 | default: | |
125 | unknown_af(af); | |
126 | break; | |
127 | } | |
128 | } | |
129 | ||
130 | int adns__guess_prefix_length(int af, const union gen_addr *addr) { | |
131 | switch (af) { | |
132 | AF_CASES(af); | |
133 | af_inet: { | |
134 | unsigned a= (ntohl(addr->v4.s_addr) >> 24) & 0xff; | |
135 | if (a < 128) return 8; | |
136 | else if (a < 192) return 16; | |
137 | else if (a < 224) return 24; | |
138 | else return -1; | |
139 | } break; | |
140 | af_inet6: | |
141 | return 64; | |
142 | default: | |
143 | unknown_af(af); | |
144 | return -1; | |
145 | } | |
146 | } | |
147 | ||
148 | int adns__addr_match_p(int addraf, const union gen_addr *addr, | |
149 | int netaf, const union gen_addr *base, | |
150 | const union gen_addr *mask) | |
151 | { | |
152 | if (addraf != netaf) return 0; | |
153 | switch (addraf) { | |
154 | AF_CASES(af); | |
155 | af_inet: | |
156 | return (addr->v4.s_addr & mask->v4.s_addr) == base->v4.s_addr; | |
157 | af_inet6: { | |
158 | int i; | |
159 | const char *a= addr->v6.s6_addr; | |
160 | const char *b= base->v6.s6_addr; | |
161 | const char *m= mask->v6.s6_addr; | |
162 | for (i = 0; i < 16; i++) | |
163 | if ((a[i] & m[i]) != b[i]) return 0; | |
164 | return 1; | |
165 | } break; | |
166 | default: | |
167 | unknown_af(addraf); | |
168 | return -1; | |
169 | } | |
170 | } | |
171 | ||
172 | void adns__sockaddr_extract(const struct sockaddr *sa, | |
173 | union gen_addr *a_r, int *port_r) { | |
174 | switch (sa->sa_family) { | |
175 | AF_CASES(af); | |
176 | af_inet: { | |
177 | const struct sockaddr_in *sin = CSIN(sa); | |
178 | if (port_r) *port_r= ntohs(sin->sin_port); | |
179 | if (a_r) a_r->v4= sin->sin_addr; | |
180 | break; | |
181 | } | |
182 | af_inet6: { | |
183 | const struct sockaddr_in6 *sin6 = CSIN6(sa); | |
184 | if (port_r) *port_r= ntohs(sin6->sin6_port); | |
185 | if (a_r) a_r->v6= sin6->sin6_addr; | |
186 | break; | |
187 | } | |
188 | default: | |
189 | unknown_af(sa->sa_family); | |
190 | } | |
191 | } | |
192 | ||
193 | void adns__sockaddr_inject(const union gen_addr *a, int port, | |
194 | struct sockaddr *sa) { | |
195 | switch (sa->sa_family) { | |
196 | AF_CASES(af); | |
197 | af_inet: { | |
198 | struct sockaddr_in *sin = SIN(sa); | |
199 | if (port != -1) sin->sin_port= htons(port); | |
200 | if (a) sin->sin_addr= a->v4; | |
201 | break; | |
202 | } | |
203 | af_inet6: { | |
204 | struct sockaddr_in6 *sin6 = SIN6(sa); | |
205 | if (port != -1) sin6->sin6_port= htons(port); | |
206 | if (a) sin6->sin6_addr= a->v6; | |
207 | break; | |
208 | } | |
209 | default: | |
210 | unknown_af(sa->sa_family); | |
211 | } | |
212 | } |