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#define OUdphdrsize Udphdrsize
#define OUdphdr Udphdr
enum
{
/* RR types */
Ta= 1,
Tns= 2,
Tmd= 3,
Tmf= 4,
Tcname= 5,
Tsoa= 6,
Tmb= 7,
Tmg= 8,
Tmr= 9,
Tnull= 10,
Twks= 11,
Tptr= 12,
Thinfo= 13,
Tminfo= 14,
Tmx= 15,
Ttxt= 16,
Trp= 17,
Tsig= 24,
Tkey= 25,
Taaaa= 28,
Tcert= 37,
/* query types (all RR types are also queries) */
Tixfr= 251, /* incremental zone transfer */
Taxfr= 252, /* zone transfer */
Tmailb= 253, /* { Tmb, Tmg, Tmr } */
Tall= 255, /* all records */
/* classes */
Csym= 0, /* internal symbols */
Cin= 1, /* internet */
Ccs, /* CSNET (obsolete) */
Cch, /* Chaos net */
Chs, /* Hesiod (?) */
/* class queries (all class types are also queries) */
Call= 255, /* all classes */
/* opcodes */
Oquery= 0<<11, /* normal query */
Oinverse= 1<<11, /* inverse query */
Ostatus= 2<<11, /* status request */
Onotify= 4<<11, /* notify slaves of updates */
Omask= 0xf<<11, /* mask for opcode */
/* response codes */
Rok= 0,
Rformat= 1, /* format error */
Rserver= 2, /* server failure (e.g. no answer from something) */
Rname= 3, /* bad name */
Runimplimented= 4, /* unimplemented */
Rrefused= 5, /* we don't like you */
Rmask= 0xf, /* mask for response */
Rtimeout= 0x10, /* timeout sending (for internal use only) */
/* bits in flag word (other than opcode and response) */
Fresp= 1<<15, /* message is a response */
Fauth= 1<<10, /* true if an authoritative response */
Ftrunc= 1<<9, /* truncated message */
Frecurse= 1<<8, /* request recursion */
Fcanrec= 1<<7, /* server can recurse */
Domlen= 256, /* max domain name length (with NULL) */
Labellen= 256, /* max domain label length (with NULL) */
Strlen= 256, /* max string length (with NULL) */
Iplen= 32, /* max ascii ip address length (with NULL) */
/* time to live values (in seconds) */
Min= 60,
Hour= 60*Min, /* */
Day= 24*Hour, /* Ta, Tmx */
Week= 7*Day, /* Tsoa, Tns */
Year= 52*Week,
DEFTTL= Day,
/* reserved time (can't be timed out earlier) */
Reserved= 5*Min,
/* packet sizes */
Maxudp= 512, /* maximum bytes per udp message */
Maxudpin= 2048, /* maximum bytes per udp message */
/* length of domain name hash table */
HTLEN= 4*1024,
RRmagic= 0xdeadbabe,
DNmagic= 0xa110a110,
/* parallelism */
Maxactive= 32,
};
typedef struct DN DN;
typedef struct DNSmsg DNSmsg;
typedef struct RR RR;
typedef struct SOA SOA;
typedef struct Area Area;
typedef struct Request Request;
typedef struct Key Key;
typedef struct Cert Cert;
typedef struct Sig Sig;
typedef struct Null Null;
typedef struct Server Server;
typedef struct Txt Txt;
/*
* a structure to track a request and any slave process handling it
*/
struct Request
{
int isslave; /* pid of slave */
ulong aborttime; /* time at which we give up */
jmp_buf mret; /* where master jumps to after starting a slave */
int id;
};
/*
* a domain name
*/
struct DN
{
DN *next; /* hash collision list */
ulong magic;
char *name; /* owner */
RR *rr; /* resource records off this name */
ulong referenced; /* time last referenced */
ulong lookuptime; /* last time we tried to get a better value */
ushort class; /* RR class */
char refs; /* for mark and sweep */
char nonexistent; /* true if we get an authoritative nx for this domain */
ulong ordinal;
};
/*
* security info
*/
struct Key
{
int flags;
int proto;
int alg;
int dlen;
uchar *data;
};
struct Cert
{
int type;
int tag;
int alg;
int dlen;
uchar *data;
};
struct Sig
{
int type;
int alg;
int labels;
ulong ttl;
ulong exp;
ulong incep;
int tag;
DN *signer;
int dlen;
uchar *data;
};
struct Null
{
int dlen;
uchar *data;
};
/*
* text strings
*/
struct Txt
{
Txt *next;
char *p;
};
/*
* an unpacked resource record
*/
struct RR
{
RR *next;
ulong magic;
DN *owner; /* domain that owns this resource record */
uchar negative; /* this is a cached negative response */
ulong pc;
ulong ttl; /* time to live to be passed on */
ulong expire; /* time this entry expires locally */
ushort type; /* RR type */
ushort query; /* query tyis is in response to */
uchar auth; /* authoritative */
uchar db; /* from database */
uchar cached; /* rr in cache */
ulong marker; /* used locally when scanning rrlists */
union {
DN *negsoaowner; /* soa for cached negative response */
DN *host; /* hostname - soa, cname, mb, md, mf, mx, ns */
DN *cpu; /* cpu type - hinfo */
DN *mb; /* mailbox - mg, minfo */
DN *ip; /* ip addrss - a */
DN *rp; /* rp arg - rp */
int cruftlen;
ulong arg0;
};
union {
int negrcode; /* response code for cached negative response */
DN *rmb; /* responsible maibox - minfo, soa, rp */
DN *ptr; /* pointer to domain name - ptr */
DN *os; /* operating system - hinfo */
ulong pref; /* preference value - mx */
ulong local; /* ns served from local database - ns */
ulong arg1;
};
union {
SOA *soa; /* soa timers - soa */
Key *key;
Cert *cert;
Sig *sig;
Null *null;
Txt *txt;
};
};
/*
* list of servers
*/
struct Server
{
Server *next;
char *name;
};
/*
* timers for a start of authenticated record
*/
struct SOA
{
ulong serial; /* zone serial # (sec) - soa */
ulong refresh; /* zone refresh interval (sec) - soa */
ulong retry; /* zone retry interval (sec) - soa */
ulong expire; /* time to expiration (sec) - soa */
ulong minttl; /* minimum time to live for any entry (sec) - soa */
Server *slaves; /* slave servers */
};
/*
* domain messages
*/
struct DNSmsg
{
ushort id;
int flags;
int qdcount; /* questions */
RR *qd;
int ancount; /* answers */
RR *an;
int nscount; /* name servers */
RR *ns;
int arcount; /* hints */
RR *ar;
};
/*
* definition of local area for dblookup
*/
struct Area
{
Area *next;
int len; /* strlen(area->soarr->owner->name) */
RR *soarr; /* soa defining this area */
int neednotify;
int needrefresh;
};
enum
{
Recurse,
Dontrecurse,
NOneg,
OKneg,
};
/* dn.c */
extern char *rrtname[];
extern char *rname[];
extern char *opname[];
extern void db2cache(int);
extern void dninit(void);
extern DN* dnlookup(char*, int, int);
extern void dnage(DN*);
extern void dnageall(int);
extern void dnagedb(void);
extern void dnauthdb(void);
extern void dnget(void);
extern void dnpurge(void);
extern void dnput(void);
extern Area* inmyarea(char*);
extern void rrattach(RR*, int);
extern RR* rralloc(int);
extern void rrfree(RR*);
extern void rrfreelist(RR*);
extern RR* rrlookup(DN*, int, int);
extern RR* rrcat(RR**, RR*);
extern RR** rrcopy(RR*, RR**);
extern RR* rrremneg(RR**);
extern RR* rrremtype(RR**, int);
extern int rrfmt(Fmt*);
extern int rravfmt(Fmt*);
extern int rrsupported(int);
extern int rrtype(char*);
extern char* rrname(int, char*, int);
extern int tsame(int, int);
extern void dndump(char*);
extern int getactivity(Request*);
extern void putactivity(void);
extern void abort(); /* char*, ... */;
extern void warning(char*, ...);
extern void slave(Request*);
extern void dncheck(void*, int);
extern void unique(RR*);
extern int subsume(char*, char*);
extern RR* randomize(RR*);
extern void* emalloc(int);
extern char* estrdup(char*);
extern void dnptr(uchar*, uchar*, char*, int, int);
extern void addserver(Server**, char*);
extern Server* copyserverlist(Server*);
extern void freeserverlist(Server*);
/* dnarea.c */
extern void refresh_areas(Area*);
extern void freearea(Area**);
extern void addarea(DN *dp, RR *rp, Ndbtuple *t);
/* dblookup.c */
extern RR* dblookup(char*, int, int, int, int);
extern RR* dbinaddr(DN*, int);
extern int baddelegation(RR*, RR*, uchar*);
extern RR* dnsservers(int);
extern RR* domainlist(int);
extern int opendatabase(void);
/* dns.c */
extern char* walkup(char*);
extern RR* getdnsservers(int);
extern void logreply(int, uchar*, DNSmsg*);
extern void logsend(int, int, uchar*, char*, char*, int);
/* dnresolve.c */
extern RR* dnresolve(char*, int, int, Request*, RR**, int, int, int, int*);
extern int udpport(void);
extern int mkreq(DN *dp, int type, uchar *buf, int flags, ushort reqno);
/* dnserver.c */
extern void dnserver(DNSmsg*, DNSmsg*, Request*);
extern void dnudpserver(void*);
extern void dntcpserver(char*);
/* dnnotify.c */
extern void dnnotify(DNSmsg*, DNSmsg*, Request*);
extern void notifyproc(void);
/* convDNS2M.c */
extern int convDNS2M(DNSmsg*, uchar*, int);
/* convM2DNS.c */
extern char* convM2DNS(uchar*, int, DNSmsg*);
/* malloc.c */
extern void mallocsanity(void*);
extern void lasthist(void*, int, ulong);
extern int debug;
extern int traceactivity;
extern char *trace;
extern int testing; /* test cache whenever removing a DN */
extern int cachedb;
extern int needrefresh;
extern char *dbfile;
extern char mntpt[];
extern char *logfile;
extern int resolver;
extern int maxage; /* age of oldest entry in cache (secs) */
extern char *zonerefreshprogram;
extern int sendnotifies;
extern ulong now; /* time base */
extern Area *owned;
extern Area *delegated;
#pragma varargck type "R" RR*
#pragma varargck type "Q" RR*
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