1/* dnsmasq is Copyright (c) 2000-2003 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. 6 7 This program is distributed in the hope that it will be useful, 8 but WITHOUT ANY WARRANTY; without even the implied warranty of 9 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 10 GNU General Public License for more details. 11*/ 12 13/* Author's email: simon@thekelleys.org.uk */ 14 15#define COPYRIGHT "Copyright (C) 2000-2004 Simon Kelley" 16 17#ifdef __linux__ 18/* for pselect.... */ 19#define _XOPEN_SOURCE 600 20/* but then DNS headers don't compile without.... */ 21#define _BSD_SOURCE 22#endif 23 24/* get these before config.h for IPv6 stuff... */ 25#include <sys/types.h> 26#include <netinet/in.h> 27 28/* get this before config.h too. */ 29#ifdef USE_SYSLOG /* foxconn wklin added, 08/13/2007 */ 30#include <syslog.h> 31#endif 32#include <arpa/nameser.h> 33 34#include "config.h" 35 36#include <arpa/inet.h> 37#include <sys/stat.h> 38#include <sys/socket.h> 39#include <sys/ioctl.h> 40#include <sys/select.h> 41#include <sys/wait.h> 42#if defined(__sun) || defined(__sun__) 43# include <sys/sockio.h> 44#endif 45#include <sys/time.h> 46#include <limits.h> 47#include <net/if.h> 48#include <unistd.h> 49#include <stdio.h> 50#include <string.h> 51#include <stdlib.h> 52#include <fcntl.h> 53#include <ctype.h> 54#include <signal.h> 55#ifdef HAVE_GETOPT_LONG 56# include <getopt.h> 57#endif 58#include <time.h> 59#include <errno.h> 60#include <pwd.h> 61#include <grp.h> 62#if defined(__OpenBSD__) || defined(__NetBSD__) 63# include <netinet/if_ether.h> 64#else 65# include <net/ethernet.h> 66#endif 67#include <net/if_arp.h> 68#include <netinet/in_systm.h> 69#include <netinet/ip.h> 70#include <netinet/ip_icmp.h> 71#ifdef HAVE_BPF 72# include <net/bpf.h> 73# include <net/if_dl.h> 74#else 75# include <netpacket/packet.h> 76#endif 77#include <sys/uio.h> 78 79/* Size: we check after adding each record, so there must be 80 memory for the largest packet, and the largest record */ 81#define DNSMASQ_PACKETSZ PACKETSZ+MAXDNAME+RRFIXEDSZ 82 83#define OPT_BOGUSPRIV 1 84#define OPT_FILTER 2 85#define OPT_LOG 4 86#define OPT_SELFMX 8 87#define OPT_NO_HOSTS 16 88#define OPT_NO_POLL 32 89#define OPT_DEBUG 64 90#define OPT_ORDER 128 91#define OPT_NO_RESOLV 256 92#define OPT_EXPAND 512 93#define OPT_LOCALMX 1024 94#define OPT_NO_NEG 2048 95#define OPT_NODOTS_LOCAL 4096 96#define OPT_NOWILD 8192 97#define OPT_ETHERS 16384 98#define OPT_RESOLV_DOMAIN 32768 99#define OPT_NO_FORK 65536 100 101struct all_addr { 102 union { 103 struct in_addr addr4; 104#ifdef HAVE_IPV6 105 struct in6_addr addr6; 106#endif 107 } addr; 108}; 109 110struct bogus_addr { 111 struct in_addr addr; 112 struct bogus_addr *next; 113}; 114 115/* dns doctor param */ 116struct doctor { 117 struct in_addr in, out, mask; 118 struct doctor *next; 119}; 120 121struct mx_record { 122 char *mxname, *mxtarget; 123 struct mx_record *next; 124}; 125 126union bigname { 127 char name[MAXDNAME]; 128 union bigname *next; /* freelist */ 129}; 130 131struct crec { 132 struct crec *next, *prev, *hash_next; 133 time_t ttd; /* time to die */ 134 struct all_addr addr; 135 unsigned short flags; 136 union { 137 char sname[SMALLDNAME]; 138 union bigname *bname; 139 char *namep; 140 } name; 141}; 142 143#define F_IMMORTAL 1 144#define F_CONFIG 2 145#define F_REVERSE 4 146#define F_FORWARD 8 147#define F_DHCP 16 148#define F_NEG 32 149#define F_HOSTS 64 150#define F_IPV4 128 151#define F_IPV6 256 152#define F_BIGNAME 512 153#define F_UPSTREAM 1024 154#define F_SERVER 2048 155#define F_NXDOMAIN 4096 156#define F_QUERY 8192 157#define F_ADDN 16384 158#define F_NOERR 32768 159 160/* struct sockaddr is not large enough to hold any address, 161 and specifically not big enough to hold and IPv6 address. 162 Blech. Roll our own. */ 163union mysockaddr { 164 struct sockaddr sa; 165 struct sockaddr_in in; 166#ifdef HAVE_BROKEN_SOCKADDR_IN6 167 /* early versions of glibc don't include sin6_scope_id in sockaddr_in6 168 but latest kernels _require_ it to be set. The choice is to have 169 dnsmasq fail to compile on back-level libc or fail to run 170 on latest kernels with IPv6. Or to do this: sorry that it's so gross. */ 171 struct my_sockaddr_in6 { 172 sa_family_t sin6_family; /* AF_INET6 */ 173 uint16_t sin6_port; /* transport layer port # */ 174 uint32_t sin6_flowinfo; /* IPv6 traffic class & flow info */ 175 struct in6_addr sin6_addr; /* IPv6 address */ 176 uint32_t sin6_scope_id; /* set of interfaces for a scope */ 177 } in6; 178#elif defined(HAVE_IPV6) 179 struct sockaddr_in6 in6; 180#endif 181}; 182 183#define SERV_FROM_RESOLV 1 /* 1 for servers from resolv, 0 for command line. */ 184#define SERV_NO_ADDR 2 /* no server, this domain is local only */ 185#define SERV_LITERAL_ADDRESS 4 /* addr is the answer, not the server */ 186#define SERV_HAS_SOURCE 8 /* source address specified */ 187#define SERV_HAS_DOMAIN 16 /* server for one domain only */ 188#define SERV_FOR_NODOTS 32 /* server for names with no domain part only */ 189#define SERV_TYPE (SERV_HAS_DOMAIN | SERV_FOR_NODOTS) 190 191struct serverfd { 192 int fd; 193 union mysockaddr source_addr; 194 struct serverfd *next; 195}; 196 197struct server { 198 union mysockaddr addr, source_addr; 199 struct serverfd *sfd; /* non-NULL if this server has its own fd bound to 200 a source port */ 201 char *domain; /* set if this server only handles a domain. */ 202 int flags, tcpfd; 203 struct server *next; 204}; 205 206struct irec { 207 union mysockaddr addr; 208 struct irec *next; 209}; 210 211struct listener { 212 int fd, tcpfd, family; 213 struct listener *next; 214}; 215 216/* interface and address parms from command line. */ 217struct iname { 218 char *name; 219 union mysockaddr addr; 220 int isloop, used; 221 struct iname *next; 222}; 223 224/* resolv-file parms from command-line */ 225struct resolvc { 226 struct resolvc *next; 227 int is_default; 228 int logged; 229 char *name; 230}; 231 232struct frec { 233 union mysockaddr source; 234 struct all_addr dest; 235 struct server *sentto; 236 unsigned int iface; 237 unsigned short orig_id, new_id; 238 //int fd; 239 //int forwardall; /* Foxconn added by EricHuang, 01/02/2008 */ 240#ifdef OPENDNS_PARENTAL_CONTROL 241 int discard_pseudoheader, fd, forwardall; /* Foxconn add, Tony W.Y. Wang, 12/02/2008, @Parental Control OpenDNS */ 242#else 243 int fd, forwardall; 244#endif 245 time_t time; 246 struct frec *next; 247}; 248 249struct dhcp_lease { 250 int clid_len; /* length of client identifier */ 251 unsigned char *clid; /* clientid */ 252 char *hostname, *fqdn; /* name from client-hostname option or config */ 253 time_t expires; /* lease expiry */ 254 unsigned char hwaddr[ETHER_ADDR_LEN]; 255 struct in_addr addr; 256 struct dhcp_lease *next; 257}; 258 259struct dhcp_netid { 260 char *net; 261 struct dhcp_netid *next; 262}; 263 264struct dhcp_config { 265 unsigned int flags; 266 int clid_len; /* length of client identifier */ 267 unsigned char *clid; /* clientid */ 268 unsigned char hwaddr[ETHER_ADDR_LEN]; 269 char *hostname; 270 struct dhcp_netid netid; 271 struct in_addr addr; 272 unsigned int lease_time; 273 struct dhcp_config *next; 274}; 275 276#define CONFIG_DISABLE 1 277#define CONFIG_CLID 2 278#define CONFIG_HWADDR 4 279#define CONFIG_TIME 8 280#define CONFIG_NAME 16 281#define CONFIG_ADDR 32 282#define CONFIG_NETID 64 283#define CONFIG_NOCLID 128 284 285struct dhcp_opt { 286 int opt, len, is_addr; 287 unsigned char *val; 288 char *netid; 289 struct dhcp_opt *next; 290}; 291 292struct dhcp_vendor { 293 int len, is_vendor, used; 294 char *data; 295 struct dhcp_netid netid; 296 struct dhcp_vendor *next; 297}; 298 299struct dhcp_context { 300 unsigned int lease_time, addr_epoch; 301 struct in_addr netmask, broadcast, router; 302 struct in_addr start, end; /* range of available addresses */ 303 int static_only; 304 struct dhcp_netid netid; 305 struct dhcp_context *next, *current; 306}; 307 308typedef unsigned char u8; 309typedef unsigned short u16; 310typedef unsigned int u32; 311 312 313struct udp_dhcp_packet { 314 struct ip ip; 315 struct udphdr { 316 u16 uh_sport; /* source port */ 317 u16 uh_dport; /* destination port */ 318 u16 uh_ulen; /* udp length */ 319 u16 uh_sum; /* udp checksum */ 320 } udp; 321 struct dhcp_packet { 322 u8 op, htype, hlen, hops; 323 u32 xid; 324 u16 secs, flags; 325 struct in_addr ciaddr, yiaddr, siaddr, giaddr; 326 u8 chaddr[16], sname[64], file[128]; 327 u8 options[312]; 328 } data; 329}; 330 331 332struct daemon { 333 /* datastuctures representing the command-line and 334 config file arguments. All set (including defaults) 335 in option.c */ 336 337 unsigned int options; 338 struct resolvc default_resolv, *resolv_files; 339 struct mx_record *mxnames; 340 char *mxtarget; 341 char *lease_file; 342 char *username, *groupname; 343 char *domain_suffix; 344 char *runfile; 345 struct iname *if_names, *if_addrs, *if_except; 346 struct bogus_addr *bogus_addr; 347 struct server *servers; 348 int cachesize; 349 int port, query_port; 350 unsigned long local_ttl; 351 char *addn_hosts; 352 struct dhcp_context *dhcp; 353 struct dhcp_config *dhcp_conf; 354 struct dhcp_opt *dhcp_opts; 355 struct dhcp_vendor *dhcp_vendors; 356 char *dhcp_file; 357 char *dhcp_sname; 358 struct in_addr dhcp_next_server; 359 int dhcp_max; 360 unsigned int min_leasetime; 361 struct doctor *doctors; 362 unsigned short edns_pktsz; 363 364 /* globally used stuff for DNS */ 365 char *packet; /* packet buffer */ 366 char *namebuff; /* MAXDNAME size buffer */ 367 struct serverfd *sfds; 368 struct listener *listeners; 369 struct server *last_server; 370 int uptime_fd; 371 372 /* DHCP state */ 373 int dhcpfd, dhcp_raw_fd, dhcp_icmp_fd, lease_fd; 374 struct udp_dhcp_packet *dhcp_packet; 375 char *dhcp_buff, *dhcp_buff2; 376 377 /* Foxconn add start, Tony W.Y. Wang, 12/02/2008, @Parental Control OpenDNS */ 378#ifdef OPENDNS_PARENTAL_CONTROL 379 /* OpenDNS device ID */ 380 int have_device_id; 381 unsigned char device_id[8]; /* In network byte-order. */ 382#endif 383 /* Foxconn add end , Tony W.Y. Wang, 12/02/2008, @Parental Control OpenDNS */ 384}; 385 386/* cache.c */ 387void cache_init(int cachesize, int log); 388void log_query(unsigned short flags, char *name, struct all_addr *addr, unsigned short type); 389struct crec *cache_find_by_addr(struct crec *crecp, 390 struct all_addr *addr, time_t now, 391 unsigned short prot); 392struct crec *cache_find_by_name(struct crec *crecp, 393 char *name, time_t now, unsigned short prot); 394void cache_end_insert(void); 395void cache_start_insert(void); 396void cache_insert(char *name, struct all_addr *addr, 397 time_t now, unsigned long ttl, unsigned short flags); 398void cache_reload(int opts, char *buff, char *domain_suffix, char *addn_hosts); 399void cache_add_dhcp_entry(char *host_name, struct in_addr *host_address, time_t ttd); 400void cache_unhash_dhcp(void); 401void dump_cache(int debug, int size); 402char *cache_get_name(struct crec *crecp); 403 404/* rfc1035.c */ 405unsigned short extract_request(HEADER *header, unsigned int qlen, 406 char *name, unsigned short *typep); 407int setup_reply(HEADER *header, unsigned int qlen, 408 struct all_addr *addrp, unsigned short flags, 409 unsigned long local_ttl); 410void extract_addresses(HEADER *header, unsigned int qlen, char *namebuff, 411 time_t now, struct doctor *doctors); 412void extract_neg_addrs(HEADER *header, unsigned int qlen, char *namebuff, time_t now, unsigned short flags); 413int answer_request(HEADER *header, char *limit, unsigned int qlen, struct daemon *daemon, time_t now); 414int check_for_bogus_wildcard(HEADER *header, unsigned int qlen, char *name, 415 struct bogus_addr *addr, time_t now); 416unsigned char *find_pseudoheader(HEADER *header, unsigned int plen, 417 unsigned int *len, unsigned char **p); 418int check_for_local_domain(char *name, time_t now, struct mx_record *mx); 419int resize_packet(HEADER *header, unsigned int plen, 420 unsigned char *pheader, unsigned int hlen); 421 422/* util.c */ 423unsigned short rand16(void); 424int legal_char(char c); 425int canonicalise(char *s); 426int atoi_check(char *a, int *res); 427void die(char *message, char *arg1); 428void complain(char *message, char *arg1); 429void *safe_malloc(int size); 430char *safe_string_alloc(char *cp); 431int sa_len(union mysockaddr *addr); 432int sockaddr_isequal(union mysockaddr *s1, union mysockaddr *s2); 433int hostname_isequal(unsigned char *a, unsigned char *b); 434time_t dnsmasq_time(int fd); 435int is_same_net(struct in_addr a, struct in_addr b, struct in_addr mask); 436 437/* option.c */ 438struct daemon *read_opts (int argc, char **argv); 439 440/* forward.c */ 441void forward_init(int first); 442void reply_query(struct serverfd *sfd, struct daemon *daemon, time_t now); 443void receive_query(struct listener *listen, struct daemon *daemon, time_t now); 444char *tcp_request(struct daemon *daemon, int confd, time_t now); 445 446/* network.c */ 447struct serverfd *allocate_sfd(union mysockaddr *addr, struct serverfd **sfds); 448void reload_servers(char *fname, struct daemon *daemon); 449void check_servers(struct daemon *daemon, struct irec *interfaces); 450struct irec *enumerate_interfaces(struct daemon *daemon); 451struct listener *create_wildcard_listeners(int port); 452struct listener *create_bound_listeners(struct irec *interfaces, int port); 453 454/* dhcp.c */ 455void dhcp_init(struct daemon *daemon); 456void dhcp_packet(struct daemon *daemon, time_t now); 457 458int address_available(struct dhcp_context *context, struct in_addr addr); 459int address_allocate(struct dhcp_context *context, struct daemon *daemon, 460 struct in_addr *addrp, unsigned char *hwaddr); 461struct dhcp_config *find_config(struct dhcp_config *configs, 462 struct dhcp_context *context, 463 unsigned char *clid, int clid_len, 464 unsigned char *hwaddr, char *hostname); 465void dhcp_update_configs(struct dhcp_config *configs); 466void dhcp_read_ethers(struct daemon *daemon); 467struct dhcp_config *config_find_by_address(struct dhcp_config *configs, struct in_addr addr); 468 469/* lease.c */ 470void lease_update_file(int force, time_t now); 471void lease_update_dns(void); 472void lease_init(struct daemon *daemon, time_t now); 473struct dhcp_lease *lease_allocate(unsigned char *clid, int clid_len, struct in_addr addr); 474void lease_set_hwaddr(struct dhcp_lease *lease, unsigned char *hwaddr); 475void lease_set_hostname(struct dhcp_lease *lease, char *name, char *suffix); 476void lease_set_expires(struct dhcp_lease *lease, time_t exp); 477struct dhcp_lease *lease_find_by_client(unsigned char *clid, int clid_len); 478struct dhcp_lease *lease_find_by_addr(struct in_addr addr); 479void lease_prune(struct dhcp_lease *target, time_t now); 480void lease_update_from_configs(struct dhcp_config *dhcp_configs, char *domain); 481 482/* rfc2131.c */ 483int dhcp_reply(struct daemon *daemon, struct in_addr iface_addr, char *iface_name, unsigned int sz, time_t now); 484 485/* dnsmasq.c */ 486int icmp_ping(struct daemon *daemon, struct in_addr addr); 487 488/* isc.c */ 489#ifdef HAVE_ISC_READER 490void load_dhcp(char *file, char *suffix, time_t now, char *hostname); 491#endif 492 493//#ifdef MULTIPLE_PPPOE 494/* foxconn wklin added start, 09/03/2007 */ 495#define MAX_KEYWORD_LEN 64 496typedef struct _keyword_t{ 497 char name[MAX_KEYWORD_LEN]; 498 struct _keyword_t *next; 499 int wildcard; /* for *.flets */ 500} keyword_t; 501/* foxconn wklin added end, 09/03/2007 */ 502 503/* foxconn added start Bob Guo, 10/24/2007 */ 504 505#define MAX_DNS_ENTRY_NUMBER 32 506typedef struct _session2_dns{ 507 int iDNSCount; 508 unsigned long DNSEntry[MAX_DNS_ENTRY_NUMBER]; 509}Session2_DNS; 510/* foxconn added end Bob Guo, 10/24/2007 */ 511//#endif 512