text: /* dnsmasq is Copyright (c) 2000-2013 Simon Kelley
   
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation; version 2 dated June, 1991, or
     (at your option) version 3 dated 29 June, 2007.
   
     This program is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.
       
     You should have received a copy of the GNU General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
  
  #define COPYRIGHT "Copyright (c) 2000-2013 Simon Kelley" 
  
  #ifndef NO_LARGEFILE
  /* Ensure we can use files >2GB (log files may grow this big) */
  #  define _LARGEFILE_SOURCE 1
  #  define _FILE_OFFSET_BITS 64
  #endif
  
  /* Get linux C library versions and define _GNU_SOURCE for kFreeBSD. */
  #if defined(__linux__) || defined(__GLIBC__)
  #  ifndef __ANDROID__
  #      define _GNU_SOURCE
  #  endif
  #  include <features.h> 
  #endif
  
  /* Need these defined early */
  #if defined(__sun) || defined(__sun__)
  #  define _XPG4_2
  #  define __EXTENSIONS__
  #endif
  
  /* get these before config.h  for IPv6 stuff... */
  #include <sys/types.h> 
  #include <sys/socket.h>
  
  #ifdef __APPLE__
  /* Define before netinet/in.h to select API. OSX Lion onwards. */
  #  define __APPLE_USE_RFC_3542
  #endif
  #include <netinet/in.h>
  
  /* Also needed before config.h. */
  #include <getopt.h>
  
  #include "config.h"
  
  typedef unsigned char u8;
  typedef unsigned short u16;
  typedef unsigned int u32;
  typedef unsigned long long u64;
  
  #include "dns-protocol.h"
  #include "dhcp-protocol.h"
  #ifdef HAVE_DHCP6
  #include "dhcp6-protocol.h"
  #include "radv-protocol.h"
  #endif
  
  #define gettext_noop(S) (S)
  #ifndef LOCALEDIR
  #  define _(S) (S)
  #else
  #  include <libintl.h>
  #  include <locale.h>   
  #  define _(S) gettext(S)
  #endif
  
  #include <arpa/inet.h>
  #include <sys/stat.h>
  #include <sys/ioctl.h>
  #if defined(HAVE_SOLARIS_NETWORK)
  #  include <sys/sockio.h>
  #endif
  #include <sys/select.h>
  #include <sys/wait.h>
  #include <sys/time.h>
  #include <sys/un.h>
  #include <limits.h>
  #include <net/if.h>
  #if defined(HAVE_SOLARIS_NETWORK) && !defined(ifr_mtu)
  /* Some solaris net/if./h omit this. */
  #  define ifr_mtu  ifr_ifru.ifru_metric
  #endif
  #include <unistd.h>
  #include <stdio.h>
  #include <string.h>
  #include <stdlib.h>
  #include <fcntl.h>
  #include <ctype.h>
  #include <signal.h>
  #include <stddef.h>
  #include <time.h>
  #include <errno.h>
  #include <pwd.h>
  #include <grp.h>
  #include <stdarg.h>
  #if defined(__OpenBSD__) || defined(__NetBSD__) || defined(__sun__) || defined (__sun) || defined (__ANDROID__)
  #  include <netinet/if_ether.h>
  #else
  #  include <net/ethernet.h>
  #endif
  #include <net/if_arp.h>
  #include <netinet/in_systm.h>
  #include <netinet/ip.h>
  #include <netinet/ip_icmp.h>
  #include <sys/uio.h>
  #include <syslog.h>
  #include <dirent.h>
  #ifndef HAVE_LINUX_NETWORK
  #  include <net/if_dl.h>
  #endif
  
  #if defined(HAVE_LINUX_NETWORK)
  #include <linux/capability.h>
  /* There doesn't seem to be a universally-available 
     userpace header for these. */
  extern int capset(cap_user_header_t header, cap_user_data_t data);
  extern int capget(cap_user_header_t header, cap_user_data_t data);
  #define LINUX_CAPABILITY_VERSION_1  0x19980330
  #define LINUX_CAPABILITY_VERSION_2  0x20071026
  #define LINUX_CAPABILITY_VERSION_3  0x20080522
  
  #include <sys/prctl.h>
  #elif defined(HAVE_SOLARIS_NETWORK)
  #include <priv.h>
  #endif
  
  /* daemon is function in the C library.... */
  #define daemon dnsmasq_daemon
  
  /* Async event queue */
  struct event_desc {
    int event, data, msg_sz;
  };
  
  #define EVENT_RELOAD    1
  #define EVENT_DUMP      2
  #define EVENT_ALARM     3
  #define EVENT_TERM      4
  #define EVENT_CHILD     5
  #define EVENT_REOPEN    6
  #define EVENT_EXITED    7
  #define EVENT_KILLED    8
  #define EVENT_EXEC_ERR  9
  #define EVENT_PIPE_ERR  10
  #define EVENT_USER_ERR  11
  #define EVENT_CAP_ERR   12
  #define EVENT_PIDFILE   13
  #define EVENT_HUSER_ERR 14
  #define EVENT_GROUP_ERR 15
  #define EVENT_DIE       16
  #define EVENT_LOG_ERR   17
  #define EVENT_FORK_ERR  18
  #define EVENT_LUA_ERR   19
  #define EVENT_TFTP_ERR  20
  
  /* Exit codes. */
  #define EC_GOOD        0
  #define EC_BADCONF     1
  #define EC_BADNET      2
  #define EC_FILE        3
  #define EC_NOMEM       4
  #define EC_MISC        5
  #define EC_INIT_OFFSET 10
  
  /* Min buffer size: we check after adding each record, so there must be 
     memory for the largest packet, and the largest record so the
     min for DNS is PACKETSZ+MAXDNAME+RRFIXEDSZ which is < 1000.
     This might be increased is EDNS packet size if greater than the minimum.
  */
  #define DNSMASQ_PACKETSZ PACKETSZ+MAXDNAME+RRFIXEDSZ
  
  /* Trust the compiler dead-code eliminator.... */
  #define option_bool(x) (((x) < 32) ? daemon->options & (1u << (x)) : daemon->options2 & (1u << ((x) - 32)))
  
  #define OPT_BOGUSPRIV      0
  #define OPT_FILTER         1
  #define OPT_LOG            2
  #define OPT_SELFMX         3
  #define OPT_NO_HOSTS       4
  #define OPT_NO_POLL        5
  #define OPT_DEBUG          6
  #define OPT_ORDER          7
  #define OPT_NO_RESOLV      8
  #define OPT_EXPAND         9
  #define OPT_LOCALMX        10
  #define OPT_NO_NEG         11
  #define OPT_NODOTS_LOCAL   12
  #define OPT_NOWILD         13
  #define OPT_ETHERS         14
  #define OPT_RESOLV_DOMAIN  15
  #define OPT_NO_FORK        16
  #define OPT_AUTHORITATIVE  17
  #define OPT_LOCALISE       18
  #define OPT_DBUS           19
  #define OPT_DHCP_FQDN      20
  #define OPT_NO_PING        21
  #define OPT_LEASE_RO       22
  #define OPT_ALL_SERVERS    23
  #define OPT_RELOAD         24
  #define OPT_LOCAL_REBIND   25  
  #define OPT_TFTP_SECURE    26
  #define OPT_TFTP_NOBLOCK   27
  #define OPT_LOG_OPTS       28
  #define OPT_TFTP_APREF     29
  #define OPT_NO_OVERRIDE    30
  #define OPT_NO_REBIND      31
  #define OPT_ADD_MAC        32
  #define OPT_DNSSEC         33
  #define OPT_CONSEC_ADDR    34
  #define OPT_CONNTRACK      35
  #define OPT_FQDN_UPDATE    36
  #define OPT_RA             37
  #define OPT_TFTP_LC        38
  #define OPT_CLEVERBIND     39
  #define OPT_TFTP           40
  #define OPT_FAST_RA        41
  
  #ifdef HAVE_QUIET_DHCP	//Originally a TOMATO option
  #define OPT_QUIET_DHCP     42
  #define OPT_QUIET_DHCP6    43
  #define OPT_QUIET_RA	   44
  #define OPT_LAST           45
  #else
  #define OPT_LAST		   42
  #endif //HAVE_QUIET_DHCP
  
  
  /* extra flags for my_syslog, we use a couple of facilities since they are known 
     not to occupy the same bits as priorities, no matter how syslog.h is set up. */
  #define MS_TFTP LOG_USER
  #define MS_DHCP LOG_DAEMON 
  
  struct all_addr {
    union {
      struct in_addr addr4;
  #ifdef HAVE_IPV6
      struct in6_addr addr6;
  #endif
    } addr;
  };
  
  struct bogus_addr {
    struct in_addr addr;
    struct bogus_addr *next;
  };
  
  /* dns doctor param */
  struct doctor {
    struct in_addr in, end, out, mask;
    struct doctor *next;
  };
  
  struct mx_srv_record {
    char *name, *target;
    int issrv, srvport, priority, weight;
    unsigned int offset;
    struct mx_srv_record *next;
  };
  
  struct naptr {
    char *name, *replace, *regexp, *services, *flags;
    unsigned int order, pref;
    struct naptr *next;
  };
  
  struct txt_record {
    char *name;
    unsigned char *txt;
    unsigned short class, len;
    struct txt_record *next;
  };
  
  struct ptr_record {
    char *name, *ptr;
    struct ptr_record *next;
  };
  
  struct cname {
    char *alias, *target;
    struct cname *next;
  };
  
  struct auth_zone {
    char *domain;
    struct subnet {
      int is6, prefixlen;
      struct in_addr addr4;
  #ifdef HAVE_IPV6
      struct in6_addr addr6;
  #endif
      struct subnet *next;
    } *subnet;
    struct auth_zone *next;
  };
  
  
  struct host_record {
    struct name_list {
      char *name;
      struct name_list *next;
    } *names;
    struct in_addr addr;
  #ifdef HAVE_IPV6
    struct in6_addr addr6;
  #endif
    struct host_record *next;
  };
  
  struct interface_name {
    char *name; /* domain name */
    char *intr; /* interface name */
    struct addrlist {
      struct all_addr addr;
      struct addrlist *next;
    } *addr4;
  #ifdef HAVE_IPV6
    struct addrlist *addr6;
  #endif
    struct interface_name *next;
  };
  
  union bigname {
    char name[MAXDNAME];
    union bigname *next; /* freelist */
  };
  
  struct keydata {
    struct keydata *next;
    unsigned char key[KEYBLOCK_LEN];
  };
  
  struct crec { 
    struct crec *next, *prev, *hash_next;
    /* union is 16 bytes when doing IPv6, 8 bytes on 32 bit machines without IPv6 */
    union {
      struct all_addr addr;
      struct {
        struct crec *cache;
        int uid;
      } cname;
      struct {
        struct keydata *keydata;
        unsigned char algo;
        unsigned char digest; /* DS only */
        unsigned short flags_or_keyid; /* flags for DNSKEY, keyid for DS */
      } key;
    } addr;
    time_t ttd; /* time to die */
    /* used as keylen if F_DS or F_DNSKEY, index to source for F_HOSTS */
    int uid; 
    unsigned short flags;
    union {
      char sname[SMALLDNAME];
      union bigname *bname;
      char *namep;
    } name;
  };
  
  #define F_IMMORTAL  (1u<<0)
  #define F_NAMEP     (1u<<1)
  #define F_REVERSE   (1u<<2)
  #define F_FORWARD   (1u<<3)
  #define F_DHCP      (1u<<4)
  #define F_NEG       (1u<<5)       
  #define F_HOSTS     (1u<<6)
  #define F_IPV4      (1u<<7)
  #define F_IPV6      (1u<<8)
  #define F_BIGNAME   (1u<<9)
  #define F_NXDOMAIN  (1u<<10)
  #define F_CNAME     (1u<<11)
  #define F_DNSKEY    (1u<<12)
  #define F_CONFIG    (1u<<13)
  #define F_DS        (1u<<14)
  #define F_DNSSECOK  (1u<<15)
  
  /* below here are only valid as args to log_query: cache
     entries are limited to 16 bits */
  #define F_UPSTREAM  (1u<<16)
  #define F_RRNAME    (1u<<17)
  #define F_SERVER    (1u<<18)
  #define F_QUERY     (1u<<19)
  #define F_NOERR     (1u<<20)
  #define F_AUTH      (1u<<21)
  
  /* composites */
  #define F_TYPE      (F_IPV4 | F_IPV6 | F_DNSKEY | F_DS) /* Only one may be set */
  
  
  
  /* struct sockaddr is not large enough to hold any address,
     and specifically not big enough to hold an IPv6 address.
     Blech. Roll our own. */
  union mysockaddr {
    struct sockaddr sa;
    struct sockaddr_in in;
  #if defined(HAVE_IPV6)
    struct sockaddr_in6 in6;
  #endif
  };
  
  /* bits in flag param to IPv6 callbacks from iface_enumerate() */
  #define IFACE_TENTATIVE   1
  #define IFACE_DEPRECATED  2
  #define IFACE_PERMANENT   4
  
  
  #define SERV_FROM_RESOLV       1  /* 1 for servers from resolv, 0 for command line. */
  #define SERV_NO_ADDR           2  /* no server, this domain is local only */
  #define SERV_LITERAL_ADDRESS   4  /* addr is the answer, not the server */ 
  #define SERV_HAS_DOMAIN        8  /* server for one domain only */
  #define SERV_HAS_SOURCE       16  /* source address defined */
  #define SERV_FOR_NODOTS       32  /* server for names with no domain part only */
  #define SERV_WARNED_RECURSIVE 64  /* avoid warning spam */
  #define SERV_FROM_DBUS       128  /* 1 if source is DBus */
  #define SERV_MARK            256  /* for mark-and-delete */
  #define SERV_TYPE    (SERV_HAS_DOMAIN | SERV_FOR_NODOTS)
  #define SERV_COUNTED         512  /* workspace for log code */
  #define SERV_USE_RESOLV     1024  /* forward this domain in the normal way */
  #define SERV_NO_REBIND      2048  /* inhibit dns-rebind protection */
  
  struct serverfd {
    int fd;
    union mysockaddr source_addr;
    char interface[IF_NAMESIZE+1];
    struct serverfd *next;
  };
  
  struct randfd {
    int fd;
    unsigned short refcount, family;
  };
    
  struct server {
    union mysockaddr addr, source_addr;
    char interface[IF_NAMESIZE+1];
    struct serverfd *sfd; 
    char *domain; /* set if this server only handles a domain. */ 
    int flags, tcpfd;
    unsigned int queries, failed_queries;
    struct server *next; 
  };
  
  struct ipsets {
    char **sets;
    char *domain;
    struct ipsets *next;
  };
  
  struct irec {
    union mysockaddr addr;
    struct in_addr netmask; /* only valid for IPv4 */
    int tftp_ok, dhcp_ok, mtu, done, dad, dns_auth, index, multicast_done;
    char *name; 
    struct irec *next;
  };
  
  struct listener {
    int fd, tcpfd, tftpfd, family;
    struct irec *iface; /* only sometimes valid for non-wildcard */
    struct listener *next;
  };
  
  /* interface and address parms from command line. */
  struct iname {
    char *name;
    union mysockaddr addr;
    int used;
    struct iname *next;
  };
  
  /* resolv-file parms from command-line */
  struct resolvc {
    struct resolvc *next;
    int is_default, logged;
    time_t mtime;
    char *name;
  };
  
  /* adn-hosts parms from command-line (also dhcp-hostsfile and dhcp-optsfile */
  #define AH_DIR      1
  #define AH_INACTIVE 2
  struct hostsfile {
    struct hostsfile *next;
    int flags;
    char *fname;
    int index; /* matches to cache entries for logging */
  };
  
  #define FREC_NOREBIND           1
  #define FREC_CHECKING_DISABLED  2
  
  struct frec {
    union mysockaddr source;
    struct all_addr dest;
    struct server *sentto; /* NULL means free */
    struct randfd *rfd4;
  #ifdef HAVE_IPV6
    struct randfd *rfd6;
  #endif
    unsigned int iface;
    unsigned short orig_id, new_id;
    int fd, forwardall, flags;
    unsigned int crc;
    time_t time;
    struct frec *next;
  };
  
  /* flags in top of length field for DHCP-option tables */
  #define OT_ADDR_LIST    0x8000
  #define OT_RFC1035_NAME 0x4000
  #define OT_INTERNAL     0x2000
  #define OT_NAME         0x1000
  #define OT_CSTRING      0x0800
  #define OT_DEC          0x0400 
  #define OT_TIME         0x0200
  
  /* actions in the daemon->helper RPC */
  #define ACTION_DEL           1
  #define ACTION_OLD_HOSTNAME  2
  #define ACTION_OLD           3
  #define ACTION_ADD           4
  #define ACTION_TFTP          5
  
  #define LEASE_NEW            1  /* newly created */
  #define LEASE_CHANGED        2  /* modified */
  #define LEASE_AUX_CHANGED    4  /* CLID or expiry changed */
  #define LEASE_AUTH_NAME      8  /* hostname came from config, not from client */
  #define LEASE_USED          16  /* used this DHCPv6 transaction */
  #define LEASE_NA            32  /* IPv6 no-temporary lease */
  #define LEASE_TA            64  /* IPv6 temporary lease */
  #define LEASE_HAVE_HWADDR  128  /* Have set hwaddress */
  
  struct dhcp_lease {
    int clid_len;          /* length of client identifier */
    unsigned char *clid;   /* clientid */
    char *hostname, *fqdn; /* name from client-hostname option or config */
    char *old_hostname;    /* hostname before it moved to another lease */
    int flags;
    time_t expires;        /* lease expiry */
  #ifdef HAVE_BROKEN_RTC
    unsigned int length;
  #endif
    int hwaddr_len, hwaddr_type; /* hw_type used for iaid in v6 */
    unsigned char hwaddr[DHCP_CHADDR_MAX]; /* also IPv6 address */
    struct in_addr addr, override, giaddr;
    unsigned char *extradata;
    unsigned int extradata_len, extradata_size;
    int last_interface;
  #ifdef HAVE_DHCP6
    struct slaac_address {
      struct in6_addr addr, local;
      time_t ping_time;
      int backoff; /* zero -> confirmed */
      struct slaac_address *next;
    } *slaac_address;
    int vendorclass_count;
  #endif
    struct dhcp_lease *next;
  };
  
  struct dhcp_netid {
    char *net;
    struct dhcp_netid *next;
  };
  
  struct dhcp_netid_list {
    struct dhcp_netid *list;
    struct dhcp_netid_list *next;
  };
  
  struct tag_if {
    struct dhcp_netid_list *set;
    struct dhcp_netid *tag;
    struct tag_if *next;
  };
  
  struct hwaddr_config {
    int hwaddr_len, hwaddr_type;
    unsigned char hwaddr[DHCP_CHADDR_MAX];
    unsigned int wildcard_mask;
    struct hwaddr_config *next;
  };
  
  struct dhcp_config {
    unsigned int flags;
    int clid_len;          /* length of client identifier */
    unsigned char *clid;   /* clientid */
    char *hostname, *domain;
    struct dhcp_netid_list *netid;
  #ifdef HAVE_DHCP6
    struct in6_addr addr6;
  #endif
    struct in_addr addr;
    time_t decline_time;
    unsigned int lease_time;
    struct hwaddr_config *hwaddr;
    struct dhcp_config *next;
  };
  
  #define have_config(config, mask) ((config) && ((config)->flags & (mask))) 
  
  #define CONFIG_DISABLE           1
  #define CONFIG_CLID              2
  #define CONFIG_TIME              8
  #define CONFIG_NAME             16
  #define CONFIG_ADDR             32
  #define CONFIG_NOCLID          128
  #define CONFIG_FROM_ETHERS     256    /* entry created by /etc/ethers */
  #define CONFIG_ADDR_HOSTS      512    /* address added by from /etc/hosts */
  #define CONFIG_DECLINED       1024    /* address declined by client */
  #define CONFIG_BANK           2048    /* from dhcp hosts file */
  #define CONFIG_ADDR6          4096
  #define CONFIG_WILDCARD       8192
  
  struct dhcp_opt {
    int opt, len, flags;
    union {
      int encap;
      unsigned int wildcard_mask;
      unsigned char *vendor_class;
    } u;
    unsigned char *val;
    struct dhcp_netid *netid;
    struct dhcp_opt *next;
  };
  
  #define DHOPT_ADDR               1
  #define DHOPT_STRING             2
  #define DHOPT_ENCAPSULATE        4
  #define DHOPT_ENCAP_MATCH        8
  #define DHOPT_FORCE             16
  #define DHOPT_BANK              32
  #define DHOPT_ENCAP_DONE        64
  #define DHOPT_MATCH            128
  #define DHOPT_VENDOR           256
  #define DHOPT_HEX              512
  #define DHOPT_VENDOR_MATCH    1024
  #define DHOPT_RFC3925         2048
  #define DHOPT_TAGOK           4096
  #define DHOPT_ADDR6           8192
  
  struct dhcp_boot {
    char *file, *sname, *tftp_sname;
    struct in_addr next_server;
    struct dhcp_netid *netid;
    struct dhcp_boot *next;
  };
  
  struct pxe_service {
    unsigned short CSA, type; 
    char *menu, *basename, *sname;
    struct in_addr server;
    struct dhcp_netid *netid;
    struct pxe_service *next;
  };
  
  #define MATCH_VENDOR     1
  #define MATCH_USER       2
  #define MATCH_CIRCUIT    3
  #define MATCH_REMOTE     4
  #define MATCH_SUBSCRIBER 5
  
  /* vendorclass, userclass, remote-id or cicuit-id */
  struct dhcp_vendor {
    int len, match_type;
    unsigned int enterprise;
    char *data;
    struct dhcp_netid netid;
    struct dhcp_vendor *next;
  };
  
  struct dhcp_mac {
    unsigned int mask;
    int hwaddr_len, hwaddr_type;
    unsigned char hwaddr[DHCP_CHADDR_MAX];
    struct dhcp_netid netid;
    struct dhcp_mac *next;
  };
  
  struct dhcp_bridge {
    char iface[IF_NAMESIZE];
    struct dhcp_bridge *alias, *next;
  };
  
  struct cond_domain {
    char *domain, *prefix;
    struct in_addr start, end;
  #ifdef HAVE_IPV6
    struct in6_addr start6, end6;
  #endif
    int is6;
    struct cond_domain *next;
  }; 
  
  #ifdef OPTION6_PREFIX_CLASS 
  struct prefix_class {
    int class;
    struct dhcp_netid tag;
    struct prefix_class *next;
  };
  #endif
  
  struct dhcp_context {
    unsigned int lease_time, addr_epoch;
    struct in_addr netmask, broadcast;
    struct in_addr local, router;
    struct in_addr start, end; /* range of available addresses */
  #ifdef HAVE_DHCP6
    struct in6_addr start6, end6; /* range of available addresses */
    struct in6_addr local6;
    int prefix, if_index;
    unsigned int valid, preferred, saved_valid;
    time_t ra_time, ra_short_period_start, address_lost_time;
    char *template_interface;
  #endif
    int flags;
    struct dhcp_netid netid, *filter;
    struct dhcp_context *next, *current;
  };
  
  #define CONTEXT_STATIC         1
  #define CONTEXT_NETMASK        2
  #define CONTEXT_BRDCAST        4
  #define CONTEXT_PROXY          8
  #define CONTEXT_RA_ONLY       16
  #define CONTEXT_RA_DONE       32
  #define CONTEXT_RA_NAME       64
  #define CONTEXT_RA_STATELESS 128
  #define CONTEXT_DHCP         256
  #define CONTEXT_DEPRECATE    512
  #define CONTEXT_TEMPLATE    1024    /* create contexts using addresses */
  #define CONTEXT_CONSTRUCTED 2048
  #define CONTEXT_GC          4096
  #define CONTEXT_RA          8192
  #define CONTEXT_CONF_USED  16384
  #define CONTEXT_USED       32768
  #define CONTEXT_NOAUTH     65536
  #define CONTEXT_OLD       131072
  
  
  struct ping_result {
    struct in_addr addr;
    time_t time;
    unsigned int hash;
    struct ping_result *next;
  };
  
  struct tftp_file {
    int refcount, fd;
    off_t size;
    dev_t dev;
    ino_t inode;
    char filename[];
  };
  
  struct tftp_transfer {
    int sockfd;
    time_t timeout;
    int backoff;
    unsigned int block, blocksize, expansion;
    off_t offset;
    union mysockaddr peer;
    char opt_blocksize, opt_transize, netascii, carrylf;
    struct tftp_file *file;
    struct tftp_transfer *next;
  };
  
  struct addr_list {
    struct in_addr addr;
    struct addr_list *next;
  };
  
  struct tftp_prefix {
    char *interface;
    char *prefix;
    struct tftp_prefix *next;
  };
  
  struct dhcp_relay {
    struct all_addr local, server;
    char *interface; /* Allowable interface for replies from server, and dest for IPv6 multicast */
    int iface_index; /* working - interface in which requests arrived, for return */
    struct dhcp_relay *current, *next;
  };
  
  extern struct daemon {
    /* datastuctures representing the command-line and 
       config file arguments. All set (including defaults)
       in option.c */
  
    unsigned int options, options2;
    struct resolvc default_resolv, *resolv_files;
    time_t last_resolv;
    struct mx_srv_record *mxnames;
    struct naptr *naptr;
    struct txt_record *txt, *rr;
    struct ptr_record *ptr;
    struct host_record *host_records, *host_records_tail;
    struct cname *cnames;
    struct auth_zone *auth_zones;
    struct interface_name *int_names;
    char *mxtarget;
    char *lease_file; 
    char *username, *groupname, *scriptuser;
    char *luascript;
    char *authserver, *hostmaster;
    struct iname *authinterface;
    struct name_list *secondary_forward_server;
    int group_set, osport;
    char *domain_suffix;
    struct cond_domain *cond_domain, *synth_domains;
    char *runfile; 
    char *lease_change_command;
    struct iname *if_names, *if_addrs, *if_except, *dhcp_except, *auth_peers, *tftp_interfaces;
    struct bogus_addr *bogus_addr;
    struct server *servers;
    struct ipsets *ipsets;
    int log_fac; /* log facility */
    char *log_file; /* optional log file */
    int max_logs;  /* queue limit */
    int cachesize, ftabsize;
    int port, query_port, min_port;
    unsigned long local_ttl, neg_ttl, max_ttl, max_cache_ttl, auth_ttl;
    struct hostsfile *addn_hosts;
    struct dhcp_context *dhcp, *dhcp6;
    struct dhcp_config *dhcp_conf;
    struct dhcp_opt *dhcp_opts, *dhcp_match, *dhcp_opts6, *dhcp_match6;
    struct dhcp_vendor *dhcp_vendors;
    struct dhcp_mac *dhcp_macs;
    struct dhcp_boot *boot_config;
    struct pxe_service *pxe_services;
    struct tag_if *tag_if; 
    struct addr_list *override_relays;
    struct dhcp_relay *relay4, *relay6;
    int override;
    int enable_pxe;
    int doing_ra, doing_dhcp6;
    struct dhcp_netid_list *dhcp_ignore, *dhcp_ignore_names, *dhcp_gen_names; 
    struct dhcp_netid_list *force_broadcast, *bootp_dynamic;
    struct hostsfile *dhcp_hosts_file, *dhcp_opts_file;
    int dhcp_max, tftp_max;
    int dhcp_server_port, dhcp_client_port;
    int start_tftp_port, end_tftp_port; 
    unsigned int min_leasetime;
    struct doctor *doctors;
    unsigned short edns_pktsz;
    char *tftp_prefix; 
    struct tftp_prefix *if_prefix; /* per-interface TFTP prefixes */
    unsigned int duid_enterprise, duid_config_len;
    unsigned char *duid_config;
    char *dbus_name;
    unsigned long soa_sn, soa_refresh, soa_retry, soa_expiry;
  #ifdef OPTION6_PREFIX_CLASS 
    struct prefix_class *prefix_classes;
  #endif
  
    /* globally used stuff for DNS */
    char *packet; /* packet buffer */
    int packet_buff_sz; /* size of above */
    char *namebuff; /* MAXDNAME size buffer */
    unsigned int local_answer, queries_forwarded;
    struct frec *frec_list;
    struct serverfd *sfds;
    struct irec *interfaces;
    struct listener *listeners;
    struct server *last_server;
    time_t forwardtime;
    int forwardcount;
    struct server *srv_save; /* Used for resend on DoD */
    size_t packet_len;       /*      "        "        */
    struct randfd *rfd_save; /*      "        "        */
    pid_t tcp_pids[MAX_PROCS];
    struct randfd randomsocks[RANDOM_SOCKS];
    int v6pktinfo; 
  
    /* DHCP state */
    int dhcpfd, helperfd, pxefd; 
  #if defined(HAVE_LINUX_NETWORK)
    int netlinkfd;
  #elif defined(HAVE_BSD_NETWORK)
    int dhcp_raw_fd, dhcp_icmp_fd;
  #endif
    struct iovec dhcp_packet;
    char *dhcp_buff, *dhcp_buff2, *dhcp_buff3;
    struct ping_result *ping_results;
    FILE *lease_stream;
    struct dhcp_bridge *bridges;
  #ifdef HAVE_DHCP6
    int duid_len;
    unsigned char *duid;
    struct iovec outpacket;
    int dhcp6fd, icmp6fd;
  #endif
    /* DBus stuff */
    /* void * here to avoid depending on dbus headers outside dbus.c */
    void *dbus;
  #ifdef HAVE_DBUS
    struct watch *watches;
  #endif
  
    /* TFTP stuff */
    struct tftp_transfer *tftp_trans, *tftp_done_trans;
  
    /* utility string buffer, hold max sized IP address as string */
    char *addrbuff;
  
  } *daemon;
  
  /* cache.c */
  void cache_init(void);
  void log_query(unsigned int flags, char *name, struct all_addr *addr, char *arg); 
  char *record_source(int index);
  void querystr(char *desc, char *str, unsigned short type);
  struct crec *cache_find_by_addr(struct crec *crecp,
  				struct all_addr *addr, time_t now, 
  				unsigned short prot);
  struct crec *cache_find_by_name(struct crec *crecp, 
  				char *name, time_t now, unsigned short  prot);
  void cache_end_insert(void);
  void cache_start_insert(void);
  struct crec *cache_insert(char *name, struct all_addr *addr,
  			  time_t now, unsigned long ttl, unsigned short flags);
  void cache_reload(void);
  void cache_add_dhcp_entry(char *host_name, int prot, struct all_addr *host_address, time_t ttd);
  struct in_addr a_record_from_hosts(char *name, time_t now);
  void cache_unhash_dhcp(void);
  void dump_cache(time_t now);
  char *cache_get_name(struct crec *crecp);
  struct crec *cache_enumerate(int init);
  #ifdef HAVE_DNSSEC
  struct keydata *keydata_alloc(char *data, size_t len);
  void keydata_free(struct keydata *blocks);
  #endif
  
  /* domain.c */
  char *get_domain(struct in_addr addr);
  #ifdef HAVE_IPV6
  char *get_domain6(struct in6_addr *addr);
  #endif
  int is_name_synthetic(int flags, char *name, struct all_addr *addr);
  int is_rev_synth(int flag, struct all_addr *addr, char *name);
  
  /* rfc1035.c */
  unsigned int extract_request(struct dns_header *header, size_t qlen, 
  			       char *name, unsigned short *typep);
  size_t setup_reply(struct dns_header *header, size_t  qlen,
  		   struct all_addr *addrp, unsigned int flags,
  		   unsigned long local_ttl);
  int extract_addresses(struct dns_header *header, size_t qlen, char *namebuff, 
  		      time_t now, char **ipsets, int is_sign, int checkrebind,
  		      int checking_disabled);
  size_t answer_request(struct dns_header *header, char *limit, size_t qlen,  
  		   struct in_addr local_addr, struct in_addr local_netmask, time_t now);
  int check_for_bogus_wildcard(struct dns_header *header, size_t qlen, char *name, 
  			     struct bogus_addr *addr, time_t now);
  unsigned char *find_pseudoheader(struct dns_header *header, size_t plen,
  				 size_t *len, unsigned char **p, int *is_sign);
  int check_for_local_domain(char *name, time_t now);
  unsigned int questions_crc(struct dns_header *header, size_t plen, char *buff);
  size_t resize_packet(struct dns_header *header, size_t plen, 
  		  unsigned char *pheader, size_t hlen);
  size_t add_mac(struct dns_header *header, size_t plen, char *limit, union mysockaddr *l3);
  int add_resource_record(struct dns_header *header, char *limit, int *truncp,
  			int nameoffset, unsigned char **pp, unsigned long ttl, 
  			int *offset, unsigned short type, unsigned short class, char *format, ...);
  unsigned char *skip_questions(struct dns_header *header, size_t plen);
  int extract_name(struct dns_header *header, size_t plen, unsigned char **pp, 
  		 char *name, int isExtract, int extrabytes);
  int in_arpa_name_2_addr(char *namein, struct all_addr *addrp);
  
  /* auth.c */
  #ifdef HAVE_AUTH
  size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t now, union mysockaddr *peer_addr);
  #endif
  
  /* util.c */
  void rand_init(void);
  unsigned short rand16(void);
  int legal_hostname(char *c);
  char *canonicalise(char *s, int *nomem);
  unsigned char *do_rfc1035_name(unsigned char *p, char *sval);
  void *safe_malloc(size_t size);
  void safe_pipe(int *fd, int read_noblock);
  void *whine_malloc(size_t size);
  int sa_len(union mysockaddr *addr);
  int sockaddr_isequal(union mysockaddr *s1, union mysockaddr *s2);
  int hostname_isequal(const char *a, const char *b);
  time_t dnsmasq_time(void);
  int is_same_net(struct in_addr a, struct in_addr b, struct in_addr mask);
  #ifdef HAVE_IPV6
  int is_same_net6(struct in6_addr *a, struct in6_addr *b, int prefixlen);
  u64 addr6part(struct in6_addr *addr);
  void setaddr6part(struct in6_addr *addr, u64 host);
  #endif
  int retry_send(void);
  void prettyprint_time(char *buf, unsigned int t);
  int prettyprint_addr(union mysockaddr *addr, char *buf);
  int parse_hex(char *in, unsigned char *out, int maxlen, 
  	      unsigned int *wildcard_mask, int *mac_type);
  int memcmp_masked(unsigned char *a, unsigned char *b, int len, 
  		  unsigned int mask);
  int expand_buf(struct iovec *iov, size_t size);
  char *print_mac(char *buff, unsigned char *mac, int len);
  void bump_maxfd(int fd, int *max);
  int read_write(int fd, unsigned char *packet, int size, int rw);
  
  int wildcard_match(const char* wildcard, const char* match);
  
  /* log.c */
  void die(char *message, char *arg1, int exit_code);
  int log_start(struct passwd *ent_pw, int errfd);
  int log_reopen(char *log_file);
  void my_syslog(int priority, const char *format, ...);
  void set_log_writer(fd_set *set, int *maxfdp);
  void check_log_writer(fd_set *set);
  void flush_log(void);
  
  /* option.c */
  void read_opts (int argc, char **argv, char *compile_opts);
  char *option_string(int prot, unsigned int opt, unsigned char *val, 
  		    int opt_len, char *buf, int buf_len);
  void reread_dhcp(void);
  void set_option_bool(unsigned int opt);
  void reset_option_bool(unsigned int opt);
  struct hostsfile *expand_filelist(struct hostsfile *list);
  char *parse_server(char *arg, union mysockaddr *addr, 
  		   union mysockaddr *source_addr, char *interface, int *flags);
  
  /* forward.c */
  void reply_query(int fd, int family, time_t now);
  void receive_query(struct listener *listen, time_t now);
  unsigned char *tcp_request(int confd, time_t now,
  			   union mysockaddr *local_addr, struct in_addr netmask, int auth_dns);
  void server_gone(struct server *server);
  struct frec *get_new_frec(time_t now, int *wait);
  int send_from(int fd, int nowild, char *packet, size_t len, 
  	       union mysockaddr *to, struct all_addr *source,
  	       unsigned int iface);
  
  /* network.c */
  int indextoname(int fd, int index, char *name);
  int local_bind(int fd, union mysockaddr *addr, char *intname, int is_tcp);
  int random_sock(int family);
  void pre_allocate_sfds(void);
  int reload_servers(char *fname);
  void check_servers(void);
  int enumerate_interfaces(int reset);
  void create_wildcard_listeners(void);
  void create_bound_listeners(int die);
  int is_dad_listeners(void);
  int iface_check(int family, struct all_addr *addr, char *name, int *auth_dns);
  int loopback_exception(int fd, int family, struct all_addr *addr, char *name);
  int label_exception(int index, int family, struct all_addr *addr);
  int fix_fd(int fd);
  int tcp_interface(int fd, int af);
  #ifdef HAVE_IPV6
  int set_ipv6pktinfo(int fd);
  #endif
  #ifdef HAVE_DHCP6
  void join_multicast(int dienow);
  #endif
  
  /* dhcp.c */
  #ifdef HAVE_DHCP
  void dhcp_init(void);
  void dhcp_packet(time_t now, int pxe_fd);
  struct dhcp_context *address_available(struct dhcp_context *context, 
  				       struct in_addr addr,
  				       struct dhcp_netid *netids);
  struct dhcp_context *narrow_context(struct dhcp_context *context, 
  				    struct in_addr taddr,
  				    struct dhcp_netid *netids);
  int address_allocate(struct dhcp_context *context,
  		     struct in_addr *addrp, unsigned char *hwaddr, int hw_len,
  		     struct dhcp_netid *netids, time_t now);
  int config_has_mac(struct dhcp_config *config, unsigned char *hwaddr, int len, int type);
  struct dhcp_config *find_config(struct dhcp_config *configs,
  				struct dhcp_context *context,
  				unsigned char *clid, int clid_len,
  				unsigned char *hwaddr, int hw_len, 
  				int hw_type, char *hostname);
  void dhcp_read_ethers(void);
  struct dhcp_config *config_find_by_address(struct dhcp_config *configs, struct in_addr addr);
  char *host_from_dns(struct in_addr addr);
  #endif
  
  /* lease.c */
  #ifdef HAVE_DHCP
  void lease_update_file(time_t now);
  void lease_update_dns(int force);
  void lease_init(time_t now);
  struct dhcp_lease *lease4_allocate(struct in_addr addr);
  #ifdef HAVE_DHCP6
  struct dhcp_lease *lease6_allocate(struct in6_addr *addrp, int lease_type);
  struct dhcp_lease *lease6_find(unsigned char *clid, int clid_len, 
  			       int lease_type, int iaid, struct in6_addr *addr);
  void lease6_reset(void);
  struct dhcp_lease *lease6_find_by_client(struct dhcp_lease *first, int lease_type, unsigned char *clid, int clid_len, int iaid);
  struct dhcp_lease *lease6_find_by_addr(struct in6_addr *net, int prefix, u64 addr);
  u64 lease_find_max_addr6(struct dhcp_context *context);
  void lease_ping_reply(struct in6_addr *sender, unsigned char *packet, char *interface);
  void lease_update_slaac(time_t now);
  #endif
  void lease_set_hwaddr(struct dhcp_lease *lease, unsigned char *hwaddr,
  		      unsigned char *clid, int hw_len, int hw_type, int clid_len, time_t now, int force);
  void lease_set_hostname(struct dhcp_lease *lease, char *name, int auth, char *domain, char *config_domain);
  void lease_set_expires(struct dhcp_lease *lease, unsigned int len, time_t now);
  void lease_set_interface(struct dhcp_lease *lease, int interface, time_t now);
  struct dhcp_lease *lease_find_by_client(unsigned char *hwaddr, int hw_len, int hw_type,  
  					unsigned char *clid, int clid_len);
  struct dhcp_lease *lease_find_by_addr(struct in_addr addr);
  struct in_addr lease_find_max_addr(struct dhcp_context *context);
  void lease_prune(struct dhcp_lease *target, time_t now);
  void lease_update_from_configs(void);
  int do_script_run(time_t now);
  void rerun_scripts(void);
  void lease_find_interfaces(time_t now);
  #ifdef HAVE_SCRIPT
  void lease_add_extradata(struct dhcp_lease *lease, unsigned char *data, 
  			 unsigned int len, int delim);
  #endif
  #endif
  
  /* rfc2131.c */
  #ifdef HAVE_DHCP
  size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
  		  size_t sz, time_t now, int unicast_dest, int *is_inform, int pxe_fd, struct in_addr fallback);
  unsigned char *extended_hwaddr(int hwtype, int hwlen, unsigned char *hwaddr, 
  			       int clid_len, unsigned char *clid, int *len_out);
  #endif
  
  /* dnsmasq.c */
  #ifdef HAVE_DHCP
  int make_icmp_sock(void);
  int icmp_ping(struct in_addr addr);
  #endif
  #ifdef HAVE_TOMATO
  void tomato_helper(time_t now);
  #endif
  #ifdef HAVE_LEASEFILE_EXPIRE //originally TOMATO option
  void flush_lease_file(time_t now);
  #endif
  void send_alarm(time_t event, time_t now);
  void send_event(int fd, int event, int data, char *msg);
  void clear_cache_and_reload(time_t now);
  void poll_resolv(int force, int do_reload, time_t now);
  
  /* netlink.c */
  #ifdef HAVE_LINUX_NETWORK
  void netlink_init(void);
  void netlink_multicast(time_t now);
  #endif
  
  /* bpf.c */
  #ifdef HAVE_BSD_NETWORK
  void init_bpf(void);
  void send_via_bpf(struct dhcp_packet *mess, size_t len,
  		  struct in_addr iface_addr, struct ifreq *ifr);
  #endif
  
  /* bpf.c or netlink.c */
  int iface_enumerate(int family, void *parm, int (callback)());
  
  /* dbus.c */
  #ifdef HAVE_DBUS
  char *dbus_init(void);
  void check_dbus_listeners(fd_set *rset, fd_set *wset, fd_set *eset);
  void set_dbus_listeners(int *maxfdp, fd_set *rset, fd_set *wset, fd_set *eset);
  #  ifdef HAVE_DHCP
  void emit_dbus_signal(int action, struct dhcp_lease *lease, char *hostname);
  #  endif
  #endif
  
  /* ipset.c */
  #ifdef HAVE_IPSET
  void ipset_init(void);
  int add_to_ipset(const char *setname, const struct all_addr *ipaddr, int flags, int remove);
  #endif
  
  /* helper.c */
  #if defined(HAVE_SCRIPT)
  int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd);
  void helper_write(void);
  void queue_script(int action, struct dhcp_lease *lease, 
  		  char *hostname, time_t now);
  #ifdef HAVE_TFTP
  void queue_tftp(off_t file_len, char *filename, union mysockaddr *peer);
  #endif
  int helper_buf_empty(void);
  #endif
  
  /* tftp.c */
  #ifdef HAVE_TFTP
  void tftp_request(struct listener *listen, time_t now);
  void check_tftp_listeners(fd_set *rset, time_t now);
  int do_tftp_script_run(void);
  #endif
  
  /* conntrack.c */
  #ifdef HAVE_CONNTRACK
  int get_incoming_mark(union mysockaddr *peer_addr, struct all_addr *local_addr,
  		      int istcp, unsigned int *markp);
  #endif
  
  /* dhcp6.c */
  #ifdef HAVE_DHCP6
  void dhcp6_init(void);
  void dhcp6_packet(time_t now);
  struct dhcp_context *address6_allocate(struct dhcp_context *context,  unsigned char *clid, int clid_len, 
  				       int iaid, int serial, struct dhcp_netid *netids, int plain_range, struct in6_addr *ans);
  int config_valid(struct dhcp_config *config, struct dhcp_context *context, struct in6_addr *addr);
  struct dhcp_context *address6_available(struct dhcp_context *context, 
  					struct in6_addr *taddr,
  					struct dhcp_netid *netids,
  					int plain_range);
  struct dhcp_context *address6_valid(struct dhcp_context *context, 
  				    struct in6_addr *taddr,
  				    struct dhcp_netid *netids,
  				    int plain_range);
  struct dhcp_config *find_config6(struct dhcp_config *configs,
  				 struct dhcp_context *context,
  				 unsigned char *duid, int duid_len,
  				 char *hostname);
  struct dhcp_config *config_find_by_address6(struct dhcp_config *configs, struct in6_addr *net, 
  					    int prefix, u64 addr);
  void make_duid(time_t now);
  void dhcp_construct_contexts(time_t now);
  #endif
  
  /* rfc3315.c */
  #ifdef HAVE_DHCP6
  unsigned short dhcp6_reply(struct dhcp_context *context, int interface, char *iface_name,  
  			   struct in6_addr *fallback, size_t sz, int is_multicast, time_t now);
  void relay_upstream6(struct dhcp_relay *relay, ssize_t sz, struct in6_addr *peer_address, u32 scope_id);
  
  unsigned short relay_reply6( struct sockaddr_in6 *peer, ssize_t sz, char *arrival_interface);
  #endif
  
  /* dhcp-common.c */
  #ifdef HAVE_DHCP
  void dhcp_common_init(void);
  ssize_t recv_dhcp_packet(int fd, struct msghdr *msg);
  struct dhcp_netid *run_tag_if(struct dhcp_netid *input);
  struct dhcp_netid *option_filter(struct dhcp_netid *tags, struct dhcp_netid *context_tags,
  				 struct dhcp_opt *opts);
  int match_netid(struct dhcp_netid *check, struct dhcp_netid *pool, int negonly);
  char *strip_hostname(char *hostname);
  void log_tags(struct dhcp_netid *netid, u32 xid);
  int match_bytes(struct dhcp_opt *o, unsigned char *p, int len);
  void dhcp_update_configs(struct dhcp_config *configs);
  void display_opts(void);
  int lookup_dhcp_opt(int prot, char *name);
  int lookup_dhcp_len(int prot, int val);
  char *option_string(int prot, unsigned int opt, unsigned char *val, 
  		    int opt_len, char *buf, int buf_len);
  #ifdef HAVE_LINUX_NETWORK
  void bindtodevice(int fd);
  #endif
  #  ifdef HAVE_DHCP6
  void display_opts6(void);
  #  endif
  void log_context(int family, struct dhcp_context *context);
  void log_relay(int family, struct dhcp_relay *relay);
  #endif
  
  /* outpacket.c */
  #ifdef HAVE_DHCP6
  void end_opt6(int container);
  int save_counter(int newval);
  void *expand(size_t headroom);
  int new_opt6(int opt);
  void *put_opt6(void *data, size_t len);
  void put_opt6_long(unsigned int val);
  void put_opt6_short(unsigned int val);
  void put_opt6_char(unsigned int val);
  void put_opt6_string(char *s);
  #endif
  
  /* radv.c */
  #ifdef HAVE_DHCP6
  void ra_init(time_t now);
  void icmp6_packet(time_t now);
  time_t periodic_ra(time_t now);
  void ra_start_unsolicted(time_t now, struct dhcp_context *context);
  #endif
  
  /* slaac.c */ 
  #ifdef HAVE_DHCP6
  void slaac_add_addrs(struct dhcp_lease *lease, time_t now, int force);
  time_t periodic_slaac(time_t now, struct dhcp_lease *leases);
  void slaac_ping_reply(struct in6_addr *sender, unsigned char *packet, char *interface, struct dhcp_lease *leases);
  #endif
  