1 /* dnsmasq is Copyright (c) 2000-2009 Simon Kelley 2 3 This program is free software; you can redistribute it and/or modify 4 it under the terms of the GNU General Public License as published by 5 the Free Software Foundation; version 2 dated June, 1991, or 6 (at your option) version 3 dated 29 June, 2007. 7 8 This program is distributed in the hope that it will be useful, 9 but WITHOUT ANY WARRANTY; without even the implied warranty of 10 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11 GNU General Public License for more details. 12 13 You should have received a copy of the GNU General Public License 14 along with this program. If not, see <http://www.gnu.org/licenses/>. 15 */ 16 17 #define VERSION "2.51" 18 19 #define FTABSIZ 150 /* max number of outstanding requests (default) */ 20 #define MAX_PROCS 20 /* max no children for TCP requests */ 21 #define CHILD_LIFETIME 150 /* secs 'till terminated (RFC1035 suggests > 120s) */ 22 #define EDNS_PKTSZ 1280 /* default max EDNS.0 UDP packet from RFC2671 */ 23 #define TIMEOUT 10 /* drop UDP queries after TIMEOUT seconds */ 24 #define FORWARD_TEST 50 /* try all servers every 50 queries */ 25 #define FORWARD_TIME 10 /* or 10 seconds */ 26 #define RANDOM_SOCKS 64 /* max simultaneous random ports */ 27 #define LEASE_RETRY 60 /* on error, retry writing leasefile after LEASE_RETRY seconds */ 28 #define CACHESIZ 150 /* default cache size */ 29 #define MAXLEASES 150 /* maximum number of DHCP leases */ 30 #define PING_WAIT 3 /* wait for ping address-in-use test */ 31 #define PING_CACHE_TIME 30 /* Ping test assumed to be valid this long. */ 32 #define DECLINE_BACKOFF 600 /* disable DECLINEd static addresses for this long */ 33 #define DHCP_PACKET_MAX 16384 /* hard limit on DHCP packet size */ 34 #define SMALLDNAME 40 /* most domain names are smaller than this */ 35 #define HOSTSFILE "/etc/hosts" 36 #ifdef __uClinux__ 37 #define RESOLVFILE "/etc/config/resolv.conf" 38 #else 39 #define RESOLVFILE "/etc/resolv.conf" 40 #endif 41 #define RUNFILE "/var/run/dnsmasq.pid" 42 43 #ifndef LEASEFILE 44 #if defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) || defined(__NetBSD__) 45 #define LEASEFILE "/var/db/dnsmasq.leases" 46 #elif defined(__sun__) || defined(__sun) 47 #define LEASEFILE "/var/cache/dnsmasq.leases" 48 #elif defined(__ANDROID__) 49 #define LEASEFILE "/data/misc/dhcp/dnsmasq.leases" 50 #else 51 #define LEASEFILE "/var/lib/misc/dnsmasq.leases" 52 #endif 53 #endif 54 55 #ifndef CONFFILE 56 #if defined(__FreeBSD__) 57 #define CONFFILE "/usr/local/etc/dnsmasq.conf" 58 #else 59 #define CONFFILE "/etc/dnsmasq.conf" 60 #endif 61 #endif 62 63 #define DEFLEASE 3600 /* default lease time, 1 hour */ 64 #define CHUSER "nobody" 65 #define CHGRP "dip" 66 #define DHCP_SERVER_PORT 67 67 #define DHCP_CLIENT_PORT 68 68 #define DHCP_SERVER_ALTPORT 1067 69 #define DHCP_CLIENT_ALTPORT 1068 70 #define LOG_MAX 5 /* log-queue length */ 71 #define RANDFILE "/dev/urandom" 72 #define DAD_WAIT 1 /* retry binding IPv6 sockets for this long */ 73 74 /* A small collection of RR-types which are missing on some platforms */ 75 76 #ifndef T_SIG 77 #define T_SIG 24 78 #endif 79 80 #ifndef T_SRV 81 #define T_SRV 33 82 #endif 83 84 #ifndef T_OPT 85 #define T_OPT 41 86 #endif 87 88 #ifndef T_TKEY 89 #define T_TKEY 249 90 #endif 91 92 #ifndef T_TSIG 93 #define T_TSIG 250 94 #endif 95 96 /* Follows system specific switches. If you run on a 97 new system, you may want to edit these. 98 May replace this with Autoconf one day. 99 100 HAVE_LINUX_NETWORK 101 HAVE_BSD_NETWORK 102 HAVE_SOLARIS_NETWORK 103 define exactly one of these to alter interaction with kernel networking. 104 105 HAVE_BROKEN_RTC 106 define this on embedded systems which don't have an RTC 107 which keeps time over reboots. Causes dnsmasq to use uptime 108 for timing, and keep lease lengths rather than expiry times 109 in its leases file. This also make dnsmasq "flash disk friendly". 110 Normally, dnsmasq tries very hard to keep the on-disk leases file 111 up-to-date: rewriting it after every renewal. When HAVE_BROKEN_RTC 112 is in effect, the lease file is only written when a new lease is 113 created, or an old one destroyed. (Because those are the only times 114 it changes.) This vastly reduces the number of file writes, and makes 115 it viable to keep the lease file on a flash filesystem. 116 NOTE: when enabling or disabling this, be sure to delete any old 117 leases file, otherwise dnsmasq may get very confused. 118 119 HAVE_DHCP 120 define this to get dnsmasq's DHCP server. 121 122 HAVE_SCRIPT 123 define this to get the ability to call scripts on lease-change 124 125 HAVE_GETOPT_LONG 126 define this if you have GNU libc or GNU getopt. 127 128 HAVE_ARC4RANDOM 129 define this if you have arc4random() to get better security from DNS spoofs 130 by using really random ids (OpenBSD) 131 132 HAVE_SOCKADDR_SA_LEN 133 define this if struct sockaddr has sa_len field (*BSD) 134 135 NOTES: 136 For Linux you should define 137 HAVE_LINUX_NETWORK 138 HAVE_GETOPT_LONG 139 you should NOT define 140 HAVE_ARC4RANDOM 141 HAVE_SOCKADDR_SA_LEN 142 143 For *BSD systems you should define 144 HAVE_BSD_NETWORK 145 HAVE_SOCKADDR_SA_LEN 146 and you MAY define 147 HAVE_ARC4RANDOM - OpenBSD and FreeBSD and NetBSD version 2.0 or later 148 HAVE_GETOPT_LONG - NetBSD, later FreeBSD 149 (FreeBSD and OpenBSD only if you link GNU getopt) 150 151 */ 152 153 /* platform independent options- uncomment to enable */ 154 #define HAVE_DHCP 155 #define HAVE_SCRIPT 156 /* #define HAVE_BROKEN_RTC */ 157 158 /* Allow DHCP to be disabled with COPTS=-DNO_DHCP */ 159 #ifdef NO_DHCP 160 #undef HAVE_DHCP 161 #endif 162 163 /* Allow scripts to be disabled with COPTS=-DNO_SCRIPT */ 164 #ifdef NO_SCRIPT 165 #undef HAVE_SCRIPT 166 #endif 167 168 /* platform dependent options. */ 169 170 /* Must preceed __linux__ since uClinux defines __linux__ too. */ 171 #if defined(__uClinux__) 172 #define HAVE_LINUX_NETWORK 173 #define HAVE_GETOPT_LONG 174 #undef HAVE_ARC4RANDOM 175 #undef HAVE_SOCKADDR_SA_LEN 176 /* Never use fork() on uClinux. Note that this is subtly different from the 177 --keep-in-foreground option, since it also suppresses forking new 178 processes for TCP connections and disables the call-a-script on leasechange 179 system. It's intended for use on MMU-less kernels. */ 180 #define NO_FORK 181 182 #elif defined(__UCLIBC__) 183 #define HAVE_LINUX_NETWORK 184 #if defined(__UCLIBC_HAS_GNU_GETOPT__) || \ 185 ((__UCLIBC_MAJOR__ == 0) && (__UCLIBC_MINOR__ == 9) && (__UCLIBC_SUBLEVEL__ < 21)) 186 #define HAVE_GETOPT_LONG 187 #endif 188 #undef HAVE_ARC4RANDOM 189 #undef HAVE_SOCKADDR_SA_LEN 190 #if !defined(__ARCH_HAS_MMU__) && !defined(__UCLIBC_HAS_MMU__) 191 #define NO_FORK 192 #endif 193 #if defined(__UCLIBC_HAS_IPV6__) 194 #ifndef IPV6_V6ONLY 195 #define IPV6_V6ONLY 26 196 #endif 197 #endif 198 199 /* This is for glibc 2.x */ 200 #elif defined(__linux__) 201 #define HAVE_LINUX_NETWORK 202 #define HAVE_GETOPT_LONG 203 #undef HAVE_ARC4RANDOM 204 #undef HAVE_SOCKADDR_SA_LEN 205 206 #elif defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) || \ 207 defined(__FreeBSD_kernel__) 208 #define HAVE_BSD_NETWORK 209 /* Later verions of FreeBSD have getopt_long() */ 210 #if defined(optional_argument) && defined(required_argument) 211 #define HAVE_GETOPT_LONG 212 #endif 213 #if !defined(__FreeBSD_kernel__) 214 #define HAVE_ARC4RANDOM 215 #endif 216 #define HAVE_SOCKADDR_SA_LEN 217 218 #elif defined(__APPLE__) 219 #define HAVE_BSD_NETWORK 220 #undef HAVE_GETOPT_LONG 221 #define HAVE_ARC4RANDOM 222 #define HAVE_SOCKADDR_SA_LEN 223 /* Define before sys/socket.h is included so we get socklen_t */ 224 #define _BSD_SOCKLEN_T_ 225 226 #elif defined(__NetBSD__) 227 #define HAVE_BSD_NETWORK 228 #define HAVE_GETOPT_LONG 229 #undef HAVE_ARC4RANDOM 230 #define HAVE_SOCKADDR_SA_LEN 231 232 #elif defined(__sun) || defined(__sun__) 233 #define HAVE_SOLARIS_NETWORK 234 #define HAVE_GETOPT_LONG 235 #undef HAVE_ARC4RANDOM 236 #undef HAVE_SOCKADDR_SA_LEN 237 #define _XPG4_2 238 #define __EXTENSIONS__ 239 #define ETHER_ADDR_LEN 6 240 241 #endif 242 243 /* Decide if we're going to support IPv6 */ 244 /* IPv6 can be forced off with "make COPTS=-DNO_IPV6" */ 245 /* We assume that systems which don't have IPv6 246 headers don't have ntop and pton either */ 247 248 #if defined(INET6_ADDRSTRLEN) && defined(IPV6_V6ONLY) && !defined(NO_IPV6) 249 #define HAVE_IPV6 250 #define ADDRSTRLEN INET6_ADDRSTRLEN 251 #if defined(SOL_IPV6) 252 #define IPV6_LEVEL SOL_IPV6 253 #else 254 #define IPV6_LEVEL IPPROTO_IPV6 255 #endif 256 #elif defined(INET_ADDRSTRLEN) 257 #undef HAVE_IPV6 258 #define ADDRSTRLEN INET_ADDRSTRLEN 259 #else 260 #undef HAVE_IPV6 261 #define ADDRSTRLEN 16 /* 4*3 + 3 dots + NULL */ 262 #endif 263 264 /* Can't do scripts without fork */ 265 #ifdef NOFORK 266 #undef HAVE_SCRIPT 267 #endif 268