| 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 <netdb.h> |
| 34 | #include <sys/socket.h> |
| 35 | #include <netinet/in.h> |
| 36 | #include <arpa/inet.h> |
| 37 | |
| 38 | #include "internal.h" |
| 39 | |
| 40 | /* |
| 41 | * IPv4 |
| 42 | */ |
| 43 | |
| 44 | #define SIN(sa) ((struct sockaddr_in *)(sa)) |
| 45 | #define CSIN(sa) ((const struct sockaddr_in *)(sa)) |
| 46 | |
| 47 | static void *inet_sockaddr_to_inaddr(struct sockaddr *sa) |
| 48 | { return &SIN(sa)->sin_addr; } |
| 49 | |
| 50 | static int inet_sockaddr_equalp(const struct sockaddr *sa, |
| 51 | const struct sockaddr *sb) |
| 52 | { |
| 53 | const struct sockaddr_in *sina = CSIN(sa), *sinb = CSIN(sb); |
| 54 | return (sina->sin_addr.s_addr == sinb->sin_addr.s_addr && |
| 55 | sina->sin_port == sinb->sin_port); |
| 56 | } |
| 57 | |
| 58 | static void inet_prefix_mask(int len, union gen_addr *mask) |
| 59 | { mask->v4.s_addr = htonl(!len ? 0 : 0xffffffff << (32 - len)); } |
| 60 | |
| 61 | static int inet_guess_len(const union gen_addr *addr) |
| 62 | { |
| 63 | unsigned a = (ntohl(addr->v4.s_addr) >> 24) & 0xff; |
| 64 | |
| 65 | if (a < 128) return 8; |
| 66 | else if (a < 192) return 16; |
| 67 | else if (a < 224) return 24; |
| 68 | else return -1; |
| 69 | } |
| 70 | |
| 71 | static int inet_matchp(const union gen_addr *addr, |
| 72 | const union gen_addr *base, |
| 73 | const union gen_addr *mask) |
| 74 | { return (addr->v4.s_addr & mask->v4.s_addr) == base->v4.s_addr; } |
| 75 | |
| 76 | static int inet_rev_parsecomp(const char *p, size_t n) |
| 77 | { |
| 78 | int i = 0; |
| 79 | if (n > 3) return -1; |
| 80 | |
| 81 | while (n--) { |
| 82 | if ('0' <= *p && *p <= '9') i = 10*i + *p++ - '0'; |
| 83 | else return -1; |
| 84 | } |
| 85 | return i; |
| 86 | } |
| 87 | |
| 88 | static void inet_rev_mkaddr(union gen_addr *addr, const byte *ipv) |
| 89 | { |
| 90 | addr->v4.s_addr = htonl((ipv[3]<<24) | (ipv[2]<<16) | |
| 91 | (ipv[1]<<8) | (ipv[0])); |
| 92 | } |
| 93 | |
| 94 | static char *inet_rev_mkname(const struct sockaddr *sa, char *buf) |
| 95 | { |
| 96 | unsigned long a = ntohl(CSIN(sa)->sin_addr.s_addr); |
| 97 | int i; |
| 98 | |
| 99 | for (i = 0; i < 4; i++) { |
| 100 | if (i) *buf++ = '.'; |
| 101 | buf += sprintf(buf, "%d", (int)(a & 0xff)); |
| 102 | a >>= 8; |
| 103 | } |
| 104 | return buf; |
| 105 | } |
| 106 | |
| 107 | const afinfo adns__inet_afinfo = { |
| 108 | AF_INET, 32, '.', 4, 3, adns_r_a, |
| 109 | inet_sockaddr_to_inaddr, inet_sockaddr_equalp, |
| 110 | inet_prefix_mask, inet_guess_len, inet_matchp, |
| 111 | inet_rev_parsecomp, inet_rev_mkaddr, inet_rev_mkname |
| 112 | }; |
| 113 | |
| 114 | /* |
| 115 | * IPv6 |
| 116 | */ |
| 117 | |
| 118 | #define SIN6(sa) ((struct sockaddr_in6 *)(sa)) |
| 119 | #define CSIN6(sa) ((const struct sockaddr_in6 *)(sa)) |
| 120 | |
| 121 | static void *inet6_sockaddr_to_inaddr(struct sockaddr *sa) |
| 122 | { return &SIN6(sa)->sin6_addr; } |
| 123 | |
| 124 | static int inet6_sockaddr_equalp(const struct sockaddr *sa, |
| 125 | const struct sockaddr *sb) |
| 126 | { |
| 127 | const struct sockaddr_in6 *sin6a = CSIN6(sa), *sin6b = CSIN6(sb); |
| 128 | return (memcmp(sin6a->sin6_addr.s6_addr, |
| 129 | sin6b->sin6_addr.s6_addr, |
| 130 | sizeof(sin6a->sin6_addr.s6_addr)) == 0 && |
| 131 | sin6a->sin6_port == sin6b->sin6_port && |
| 132 | sin6a->sin6_scope_id == sin6b->sin6_scope_id); |
| 133 | } |
| 134 | |
| 135 | static void inet6_prefix_mask(int len, union gen_addr *mask) |
| 136 | { |
| 137 | int i = len/8, j = len%8; |
| 138 | unsigned char *m = mask->v6.s6_addr; |
| 139 | |
| 140 | assert(len < 128); |
| 141 | memset(m, 0xff, i); |
| 142 | if (j) m[i++] = (0xff << (8-j)) & 0xff; |
| 143 | memset(m + i, 0, 16-i); |
| 144 | } |
| 145 | |
| 146 | static int inet6_guess_len(const union gen_addr *addr) |
| 147 | { return 64; } |
| 148 | |
| 149 | static int inet6_matchp(const union gen_addr *addr, |
| 150 | const union gen_addr *base, |
| 151 | const union gen_addr *mask) |
| 152 | { |
| 153 | int i; |
| 154 | const char *a = addr->v6.s6_addr; |
| 155 | const char *b = base->v6.s6_addr; |
| 156 | const char *m = mask->v6.s6_addr; |
| 157 | |
| 158 | for (i = 0; i < 16; i++) |
| 159 | if ((a[i] & m[i]) != b[i]) return 0; |
| 160 | return 1; |
| 161 | } |
| 162 | |
| 163 | static int inet6_rev_parsecomp(const char *p, size_t n) |
| 164 | { |
| 165 | if (n != 1) return -1; |
| 166 | else if ('0' <= *p && *p <= '9') return *p - '0'; |
| 167 | else if ('a' <= *p && *p <= 'f') return *p - 'a' + 10; |
| 168 | else if ('A' <= *p && *p <= 'F') return *p - 'a' + 10; |
| 169 | else return -1; |
| 170 | } |
| 171 | |
| 172 | static void inet6_rev_mkaddr(union gen_addr *addr, const byte *ipv) |
| 173 | { |
| 174 | unsigned char *a = addr->v6.s6_addr; |
| 175 | int i; |
| 176 | |
| 177 | for (i = 0; i < 16; i++) |
| 178 | a[i] = (ipv[31-2*i] << 4) | (ipv[30-2*i] << 0); |
| 179 | } |
| 180 | |
| 181 | static char *inet6_rev_mkname(const struct sockaddr *sa, char *buf) |
| 182 | { |
| 183 | const unsigned char *a = CSIN6(sa)->sin6_addr.s6_addr + 16; |
| 184 | unsigned c, y; |
| 185 | int i, j; |
| 186 | |
| 187 | for (i = 0; i < 16; i++) { |
| 188 | c = *--a; |
| 189 | for (j = 0; j < 2; j++) { |
| 190 | if (i || j) *buf++ = '.'; |
| 191 | y = c & 0xf; |
| 192 | if (y < 10) *buf++ = y + '0'; |
| 193 | else *buf++ = y - 10 + 'a'; |
| 194 | c >>= 4; |
| 195 | } |
| 196 | } |
| 197 | return buf; |
| 198 | } |
| 199 | |
| 200 | const afinfo adns__inet6_afinfo = { |
| 201 | AF_INET6, 128, ':', 32, 1, adns_r_aaaa, |
| 202 | inet6_sockaddr_to_inaddr, inet6_sockaddr_equalp, |
| 203 | inet6_prefix_mask, inet6_guess_len, inet6_matchp, |
| 204 | inet6_rev_parsecomp, inet6_rev_mkaddr, inet6_rev_mkname |
| 205 | }; |