1982 lines
37 KiB
C
1982 lines
37 KiB
C
#include <u.h>
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#include <libc.h>
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#include <ip.h>
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#include <ctype.h>
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#include "dns.h"
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/*
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* this comment used to say `our target is 4000 names cached, this should
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* be larger on large servers'. dns at Bell Labs starts off with
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* about 1780 names.
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*
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* aging seems to corrupt the cache, so raise the trigger from 4000 until we
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* figure it out.
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*/
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enum {
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/* these settings will trigger frequent aging */
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Deftarget = 4000,
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Minage = 5*Min,
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Defagefreq = 15*Min, /* age names this often (seconds) */
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};
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/*
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* Hash table for domain names. The hash is based only on the
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* first element of the domain name.
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*/
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DN *ht[HTLEN];
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static struct {
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Lock;
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uint32_t names; /* names allocated */
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uint32_t oldest; /* longest we'll leave a name around */
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int active;
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int mutex;
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uint16_t id; /* same size as in packet */
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} dnvars;
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/* names of RR types */
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char *rrtname[] =
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{
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[Ta] "ip",
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[Tns] "ns",
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[Tmd] "md",
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[Tmf] "mf",
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[Tcname] "cname",
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[Tsoa] "soa",
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[Tmb] "mb",
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[Tmg] "mg",
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[Tmr] "mr",
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[Tnull] "null",
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[Twks] "wks",
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[Tptr] "ptr",
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[Thinfo] "hinfo",
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[Tminfo] "minfo",
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[Tmx] "mx",
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[Ttxt] "txt",
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[Trp] "rp",
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[Tafsdb] "afsdb",
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[Tx25] "x.25",
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[Tisdn] "isdn",
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[Trt] "rt",
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[Tnsap] "nsap",
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[Tnsapptr] "nsap-ptr",
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[Tsig] "sig",
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[Tkey] "key",
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[Tpx] "px",
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[Tgpos] "gpos",
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[Taaaa] "ipv6",
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[Tloc] "loc",
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[Tnxt] "nxt",
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[Teid] "eid",
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[Tnimloc] "nimrod",
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[Tsrv] "srv",
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[Tatma] "atma",
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[Tnaptr] "naptr",
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[Tkx] "kx",
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[Tcert] "cert",
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[Ta6] "a6",
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[Tdname] "dname",
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[Tsink] "sink",
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[Topt] "opt",
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[Tapl] "apl",
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[Tds] "ds",
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[Tsshfp] "sshfp",
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[Tipseckey] "ipseckey",
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[Trrsig] "rrsig",
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[Tnsec] "nsec",
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[Tdnskey] "dnskey",
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[Tspf] "spf",
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[Tuinfo] "uinfo",
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[Tuid] "uid",
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[Tgid] "gid",
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[Tunspec] "unspec",
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[Ttkey] "tkey",
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[Ttsig] "tsig",
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[Tixfr] "ixfr",
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[Taxfr] "axfr",
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[Tmailb] "mailb",
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[Tmaila] "maila",
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[Tall] "all",
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0,
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};
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/* names of response codes */
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char *rname[Rmask+1] =
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{
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[Rok] "ok",
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[Rformat] "format error",
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[Rserver] "server failure",
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[Rname] "bad name",
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[Runimplimented] "unimplemented",
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[Rrefused] "we don't like you",
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[Ryxdomain] "name should not exist",
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[Ryxrrset] "rr set should not exist",
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[Rnxrrset] "rr set should exist",
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[Rnotauth] "not authorative",
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[Rnotzone] "not in zone",
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[Rbadvers] "bad opt version",
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/* [Rbadsig] "bad signature", */
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[Rbadkey] "bad key",
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[Rbadtime] "bad signature time",
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[Rbadmode] "bad mode",
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[Rbadname] "duplicate key name",
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[Rbadalg] "bad algorithm",
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};
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unsigned nrname = nelem(rname);
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/* names of op codes */
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char *opname[] =
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{
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[Oquery] "query",
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[Oinverse] "inverse query (retired)",
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[Ostatus] "status",
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[Oupdate] "update",
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};
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uint32_t target = Deftarget;
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Lock dnlock;
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static uint32_t agefreq = Defagefreq;
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static int rrequiv(RR *r1, RR *r2);
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static int sencodefmt(Fmt*);
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static void
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ding(void* _1, char *msg)
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{
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if(strstr(msg, "alarm") != nil) {
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stats.alarms++;
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noted(NCONT); /* resume with system call error */
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} else
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noted(NDFLT); /* die */
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}
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void
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dninit(void)
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{
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fmtinstall('E', eipfmt);
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fmtinstall('I', eipfmt);
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fmtinstall('V', eipfmt);
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fmtinstall('R', rrfmt);
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fmtinstall('Q', rravfmt);
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fmtinstall('H', sencodefmt);
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dnvars.oldest = maxage;
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dnvars.names = 0;
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dnvars.id = truerand(); /* don't start with same id every time */
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notify(ding);
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}
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/*
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* hash for a domain name
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*/
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static uint32_t
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dnhash(char *name)
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{
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uint32_t hash;
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uint8_t *val = (uint8_t*)name;
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for(hash = 0; *val; val++)
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hash = hash*13 + tolower(*val)-'a';
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return hash % HTLEN;
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}
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/*
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* lookup a symbol. if enter is not zero and the name is
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* not found, create it.
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*/
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DN*
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dnlookup(char *name, int class, int enter)
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{
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DN **l;
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DN *dp;
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l = &ht[dnhash(name)];
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lock(&dnlock);
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for(dp = *l; dp; dp = dp->next) {
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assert(dp->magic == DNmagic);
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if(dp->class == class && cistrcmp(dp->name, name) == 0){
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dp->referenced = now;
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unlock(&dnlock);
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return dp;
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}
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l = &dp->next;
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}
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if(!enter){
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unlock(&dnlock);
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return 0;
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}
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dnvars.names++;
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dp = emalloc(sizeof(*dp));
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dp->magic = DNmagic;
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dp->name = estrdup(name);
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dp->class = class;
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dp->rr = nil;
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dp->referenced = now;
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/* add new DN to tail of the hash list. *l points to last next ptr. */
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dp->next = nil;
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*l = dp;
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unlock(&dnlock);
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return dp;
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}
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DN*
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idnlookup(char *name, int class, int enter)
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{
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char dom[Domlen];
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if(utf2idn(name, dom, sizeof dom) != nil)
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name = dom;
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return dnlookup(name, class, enter);
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}
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static int
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rrsame(RR *rr1, RR *rr2)
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{
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return rr1 == rr2 || rr2 && rrequiv(rr1, rr2) &&
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rr1->db == rr2->db && rr1->auth == rr2->auth;
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}
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static int
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rronlist(RR *rp, RR *lp)
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{
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for(; lp; lp = lp->next)
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if (rrsame(lp, rp))
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return 1;
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return 0;
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}
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/*
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* dump the stats
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*/
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void
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dnstats(char *file)
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{
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int i, fd;
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fd = ocreate(file, OWRITE, 0666);
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if(fd < 0)
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return;
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qlock(&stats);
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fprint(fd, "# system %s\n", sysname());
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fprint(fd, "# slave procs high-water mark\t%lud\n", stats.slavehiwat);
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fprint(fd, "# queries received by 9p\t%lud\n", stats.qrecvd9p);
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fprint(fd, "# queries received by udp\t%lud\n", stats.qrecvdudp);
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fprint(fd, "# queries answered from memory\t%lud\n", stats.answinmem);
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fprint(fd, "# queries sent by udp\t%lud\n", stats.qsent);
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for (i = 0; i < nelem(stats.under10ths); i++)
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if (stats.under10ths[i] || i == nelem(stats.under10ths) - 1)
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fprint(fd, "# responses arriving within %.1f s.\t%lud\n",
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(double)(i+1)/10, stats.under10ths[i]);
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fprint(fd, "\n# queries sent & timed-out\t%lud\n", stats.tmout);
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fprint(fd, "# cname queries timed-out\t%lud\n", stats.tmoutcname);
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fprint(fd, "# ipv6 queries timed-out\t%lud\n", stats.tmoutv6);
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fprint(fd, "\n# negative answers received\t%lud\n", stats.negans);
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fprint(fd, "# negative answers w Rserver set\t%lud\n", stats.negserver);
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fprint(fd, "# negative answers w bad delegation\t%lud\n",
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stats.negbaddeleg);
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fprint(fd, "# negative answers w bad delegation & no answers\t%lud\n",
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stats.negbdnoans);
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fprint(fd, "# negative answers w no Rname set\t%lud\n", stats.negnorname);
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fprint(fd, "# negative answers cached\t%lud\n", stats.negcached);
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qunlock(&stats);
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lock(&dnlock);
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fprint(fd, "\n# domain names %lud target %lud\n", dnvars.names, target);
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unlock(&dnlock);
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close(fd);
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}
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/*
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* dump the cache
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*/
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void
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dndump(char *file)
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{
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int i, fd;
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DN *dp;
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RR *rp;
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fd = ocreate(file, OWRITE, 0666);
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if(fd < 0)
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return;
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lock(&dnlock);
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for(i = 0; i < HTLEN; i++)
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for(dp = ht[i]; dp; dp = dp->next){
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fprint(fd, "%s\n", dp->name);
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for(rp = dp->rr; rp; rp = rp->next) {
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fprint(fd, "\t%R %c%c %ld/%lud\n",
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rp, rp->auth? 'A': 'U',
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rp->db? 'D': 'N', (int32_t)(rp->expire - now), rp->ttl);
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if (rronlist(rp, rp->next))
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fprint(fd, "*** duplicate:\n");
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}
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}
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unlock(&dnlock);
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close(fd);
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}
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/*
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* purge all records
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*/
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void
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dnpurge(void)
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{
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DN *dp;
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RR *rp, *srp;
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int i;
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lock(&dnlock);
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for(i = 0; i < HTLEN; i++)
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for(dp = ht[i]; dp; dp = dp->next){
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srp = rp = dp->rr;
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dp->rr = nil;
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for(; rp != nil; rp = rp->next)
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rp->cached = 0;
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rrfreelist(srp);
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}
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unlock(&dnlock);
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}
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/*
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* delete head of *l and free the old head.
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* call with dnlock held.
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*/
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static void
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rrdelhead(RR **l)
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{
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RR *rp;
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if (canlock(&dnlock))
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abort(); /* rrdelhead called with dnlock not held */
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rp = *l;
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if(rp == nil)
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return;
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*l = rp->next; /* unlink head */
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rp->cached = 0; /* avoid blowing an assertion in rrfree */
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rrfree(rp);
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}
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/*
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* check the age of resource records, free any that have timed out.
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* call with dnlock held.
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*/
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void
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dnage(DN *dp)
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{
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RR **l, *rp;
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uint32_t diff;
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if (canlock(&dnlock))
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abort(); /* dnage called with dnlock not held */
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diff = now - dp->referenced;
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if(diff < Reserved || dp->mark != 0)
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return;
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l = &dp->rr;
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while ((rp = *l) != nil){
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assert(rp->magic == RRmagic && rp->cached);
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if(!rp->db && ((int32_t)(rp->expire - now) <= 0 || diff > dnvars.oldest))
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rrdelhead(l); /* rp == *l before; *l == rp->next after */
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else
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l = &rp->next;
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}
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}
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#define MARK(dp) { if (dp) (dp)->mark |= 2; }
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/* mark a domain name and those in its RRs as never to be aged */
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void
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dnagenever(DN *dp)
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{
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RR *rp;
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lock(&dnlock);
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/* mark all referenced domain names */
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MARK(dp);
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for(rp = dp->rr; rp; rp = rp->next){
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MARK(rp->owner);
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if(rp->negative){
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MARK(rp->negsoaowner);
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continue;
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}
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switch(rp->type){
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case Thinfo:
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MARK(rp->cpu);
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MARK(rp->os);
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break;
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case Ttxt:
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break;
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case Tcname:
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case Tmb:
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case Tmd:
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case Tmf:
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case Tns:
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case Tmx:
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case Tsrv:
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MARK(rp->host);
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break;
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case Tmg:
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case Tmr:
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MARK(rp->mb);
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break;
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case Tminfo:
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MARK(rp->rmb);
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MARK(rp->mb);
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break;
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case Trp:
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MARK(rp->rmb);
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MARK(rp->rp);
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break;
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case Ta:
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case Taaaa:
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MARK(rp->ip);
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break;
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case Tptr:
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MARK(rp->ptr);
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break;
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case Tsoa:
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MARK(rp->host);
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MARK(rp->rmb);
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break;
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case Tsig:
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MARK(rp->sig->signer);
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break;
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}
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}
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unlock(&dnlock);
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}
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#define REF(dp) { if (dp) (dp)->mark |= 1; }
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/*
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* periodicly sweep for old records and remove unreferenced domain names
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*
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* only called when all other threads are locked out
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*/
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void
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dnageall(int doit)
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{
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DN *dp, **l;
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int i;
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RR *rp;
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static uint32_t nextage;
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if(dnvars.names < target || ((int32_t)(nextage - now) > 0 && !doit)){
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dnvars.oldest = maxage;
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return;
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}
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if(dnvars.names >= target) {
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dnslog("more names (%lud) than target (%lud)", dnvars.names,
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target);
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dnvars.oldest /= 2;
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if (dnvars.oldest < Minage)
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dnvars.oldest = Minage; /* don't be silly */
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}
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if (agefreq > dnvars.oldest / 2)
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nextage = now + dnvars.oldest / 2;
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else
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nextage = now + (uint32_t)agefreq;
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lock(&dnlock);
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/* time out all old entries (and set refs to 0) */
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for(i = 0; i < HTLEN; i++)
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for(dp = ht[i]; dp; dp = dp->next){
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dp->mark &= ~1;
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dnage(dp);
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}
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/* mark all referenced domain names */
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for(i = 0; i < HTLEN; i++)
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for(dp = ht[i]; dp; dp = dp->next)
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for(rp = dp->rr; rp; rp = rp->next){
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REF(rp->owner);
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if(rp->negative){
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REF(rp->negsoaowner);
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continue;
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}
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switch(rp->type){
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case Thinfo:
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REF(rp->cpu);
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REF(rp->os);
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break;
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case Ttxt:
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break;
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case Tcname:
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case Tmb:
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case Tmd:
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case Tmf:
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case Tns:
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case Tmx:
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case Tsrv:
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REF(rp->host);
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break;
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case Tmg:
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case Tmr:
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REF(rp->mb);
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break;
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case Tminfo:
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REF(rp->rmb);
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REF(rp->mb);
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break;
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case Trp:
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REF(rp->rmb);
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REF(rp->rp);
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break;
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case Ta:
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case Taaaa:
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REF(rp->ip);
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break;
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case Tptr:
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REF(rp->ptr);
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break;
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case Tsoa:
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REF(rp->host);
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REF(rp->rmb);
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break;
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case Tsig:
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REF(rp->sig->signer);
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break;
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}
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}
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/* sweep and remove unreferenced domain names */
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for(i = 0; i < HTLEN; i++){
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l = &ht[i];
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for(dp = *l; dp; dp = *l){
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if(dp->rr == nil && dp->mark == 0){
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assert(dp->magic == DNmagic);
|
|
*l = dp->next;
|
|
|
|
free(dp->name);
|
|
memset(dp, 0, sizeof *dp); /* cause trouble */
|
|
dp->magic = ~DNmagic;
|
|
free(dp);
|
|
|
|
dnvars.names--;
|
|
continue;
|
|
}
|
|
l = &dp->next;
|
|
}
|
|
}
|
|
|
|
unlock(&dnlock);
|
|
}
|
|
|
|
/*
|
|
* timeout all database records (used when rereading db)
|
|
*/
|
|
void
|
|
dnagedb(void)
|
|
{
|
|
DN *dp;
|
|
int i;
|
|
RR *rp;
|
|
|
|
lock(&dnlock);
|
|
|
|
/* time out all database entries */
|
|
for(i = 0; i < HTLEN; i++)
|
|
for(dp = ht[i]; dp; dp = dp->next) {
|
|
dp->mark = 0;
|
|
for(rp = dp->rr; rp; rp = rp->next)
|
|
if(rp->db)
|
|
rp->expire = 0;
|
|
}
|
|
|
|
unlock(&dnlock);
|
|
}
|
|
|
|
/*
|
|
* mark all local db records about my area as authoritative,
|
|
* delete timed out ones
|
|
*/
|
|
void
|
|
dnauthdb(void)
|
|
{
|
|
int i;
|
|
uint32_t minttl;
|
|
Area *area;
|
|
DN *dp;
|
|
RR *rp, **l;
|
|
|
|
lock(&dnlock);
|
|
|
|
/* time out all database entries */
|
|
for(i = 0; i < HTLEN; i++)
|
|
for(dp = ht[i]; dp; dp = dp->next){
|
|
area = inmyarea(dp->name);
|
|
l = &dp->rr;
|
|
for(rp = *l; rp; rp = *l){
|
|
if(rp->db){
|
|
if(rp->expire == 0){
|
|
rrdelhead(l);
|
|
continue;
|
|
}
|
|
if(area){
|
|
minttl = area->soarr->soa->minttl;
|
|
if(rp->ttl < minttl)
|
|
rp->ttl = minttl;
|
|
rp->auth = 1;
|
|
}
|
|
}
|
|
l = &rp->next;
|
|
}
|
|
}
|
|
|
|
unlock(&dnlock);
|
|
}
|
|
|
|
/*
|
|
* keep track of other processes to know if we can
|
|
* garbage collect. block while garbage collecting.
|
|
*/
|
|
int
|
|
getactivity(Request *req, int recursive)
|
|
{
|
|
int rv;
|
|
|
|
if(traceactivity)
|
|
dnslog("get: %d active by pid %d from %p",
|
|
dnvars.active, getpid(), getcallerpc());
|
|
lock(&dnvars);
|
|
/*
|
|
* can't block here if we're already holding one
|
|
* of the dnvars.active (recursive). will deadlock.
|
|
*/
|
|
while(!recursive && dnvars.mutex){
|
|
unlock(&dnvars);
|
|
sleep(100); /* tune; was 200 */
|
|
lock(&dnvars);
|
|
}
|
|
rv = ++dnvars.active;
|
|
now = time(nil);
|
|
nowns = nsec();
|
|
req->id = ++dnvars.id;
|
|
req->aux = nil;
|
|
unlock(&dnvars);
|
|
|
|
return rv;
|
|
}
|
|
void
|
|
putactivity(int recursive)
|
|
{
|
|
if(traceactivity)
|
|
dnslog("put: %d active by pid %d",
|
|
dnvars.active, getpid());
|
|
lock(&dnvars);
|
|
dnvars.active--;
|
|
assert(dnvars.active >= 0); /* "dnvars.active %d", dnvars.active */
|
|
|
|
/*
|
|
* clean out old entries and check for new db periodicly
|
|
* can't block here if being called to let go a "recursive" lock
|
|
* or we'll deadlock waiting for ourselves to give up the dnvars.active.
|
|
*/
|
|
if (recursive || dnvars.mutex ||
|
|
(needrefresh == 0 && dnvars.active > 0)){
|
|
unlock(&dnvars);
|
|
return;
|
|
}
|
|
|
|
/* wait till we're alone */
|
|
dnvars.mutex = 1;
|
|
while(dnvars.active > 0){
|
|
unlock(&dnvars);
|
|
sleep(100); /* tune; was 100 */
|
|
lock(&dnvars);
|
|
}
|
|
unlock(&dnvars);
|
|
|
|
db2cache(needrefresh);
|
|
|
|
dnageall(0);
|
|
|
|
/* let others back in */
|
|
needrefresh = 0;
|
|
dnvars.mutex = 0;
|
|
}
|
|
|
|
int
|
|
rrlistlen(RR *rp)
|
|
{
|
|
int n;
|
|
|
|
n = 0;
|
|
for(; rp; rp = rp->next)
|
|
++n;
|
|
return n;
|
|
}
|
|
|
|
/*
|
|
* Attach a single resource record to a domain name (new->owner).
|
|
* - Avoid duplicates with already present RR's
|
|
* - Chain all RR's of the same type adjacent to one another
|
|
* - chain authoritative RR's ahead of non-authoritative ones
|
|
* - remove any expired RR's
|
|
* If new is a stale duplicate, rrfree it.
|
|
* Must be called with dnlock held.
|
|
*/
|
|
static void
|
|
rrattach1(RR *new, int auth)
|
|
{
|
|
RR **l;
|
|
RR *rp;
|
|
DN *dp;
|
|
uint32_t ttl;
|
|
|
|
assert(new->magic == RRmagic && !new->cached);
|
|
|
|
dp = new->owner;
|
|
assert(dp != nil && dp->magic == DNmagic);
|
|
new->auth |= auth;
|
|
new->next = 0;
|
|
|
|
/*
|
|
* try not to let responses expire before we
|
|
* can use them to complete this query, by extending
|
|
* past (or nearly past) expiration time.
|
|
*/
|
|
if(new->db)
|
|
ttl = Year;
|
|
else
|
|
ttl = new->ttl;
|
|
if(ttl <= Min)
|
|
ttl = 10*Min;
|
|
new->expire = now + ttl;
|
|
|
|
/*
|
|
* find first rr of the right type
|
|
*/
|
|
l = &dp->rr;
|
|
for(rp = *l; rp; rp = *l){
|
|
assert(rp->magic == RRmagic && rp->cached);
|
|
if(rp->type == new->type)
|
|
break;
|
|
l = &rp->next;
|
|
}
|
|
|
|
/*
|
|
* negative entries replace positive entries
|
|
* positive entries replace negative entries
|
|
* newer entries replace older entries with the same fields
|
|
*
|
|
* look farther ahead than just the next entry when looking
|
|
* for duplicates; RRs of a given type can have different rdata
|
|
* fields (e.g. multiple NS servers).
|
|
*/
|
|
while ((rp = *l) != nil){
|
|
assert(rp->magic == RRmagic && rp->cached);
|
|
if(rp->type != new->type)
|
|
break;
|
|
|
|
if(rp->db == new->db && rp->auth == new->auth){
|
|
/* negative drives out positive and vice versa */
|
|
if(rp->negative != new->negative) {
|
|
/* rp == *l before; *l == rp->next after */
|
|
rrdelhead(l);
|
|
continue;
|
|
}
|
|
/* all things equal, pick the newer one */
|
|
else if(rp->arg0 == new->arg0 && rp->arg1 == new->arg1){
|
|
/* old drives out new */
|
|
if((int32_t)(rp->expire - new->expire) > 0) {
|
|
rrfree(new);
|
|
return;
|
|
}
|
|
/* rp == *l before; *l == rp->next after */
|
|
rrdelhead(l);
|
|
continue;
|
|
}
|
|
/*
|
|
* Hack for pointer records. This makes sure
|
|
* the ordering in the list reflects the ordering
|
|
* received or read from the database
|
|
*/
|
|
else if(rp->type == Tptr &&
|
|
!rp->negative && !new->negative &&
|
|
rp->ptr->ordinal > new->ptr->ordinal)
|
|
break;
|
|
}
|
|
l = &rp->next;
|
|
}
|
|
|
|
if (rronlist(new, rp)) {
|
|
/* should not happen; duplicates were processed above */
|
|
dnslog("adding duplicate %R to list of %R; aborting", new, rp);
|
|
abort();
|
|
}
|
|
/*
|
|
* add to chain
|
|
*/
|
|
new->cached = 1;
|
|
new->next = rp;
|
|
*l = new;
|
|
}
|
|
|
|
/*
|
|
* Attach a list of resource records to a domain name.
|
|
* May rrfree any stale duplicate RRs; dismembers the list.
|
|
* Upon return, every RR in the list will have been rrfree-d
|
|
* or attached to its domain name.
|
|
* See rrattach1 for properties preserved.
|
|
*/
|
|
void
|
|
rrattach(RR *rp, int auth)
|
|
{
|
|
RR *next;
|
|
DN *dp;
|
|
|
|
lock(&dnlock);
|
|
for(; rp; rp = next){
|
|
next = rp->next;
|
|
rp->next = nil;
|
|
dp = rp->owner;
|
|
/* avoid any outside spoofing */
|
|
if(cfg.cachedb && !rp->db && inmyarea(dp->name))
|
|
rrfree(rp);
|
|
else
|
|
rrattach1(rp, auth);
|
|
}
|
|
unlock(&dnlock);
|
|
}
|
|
|
|
RR**
|
|
rrcopy(RR *rp, RR **last)
|
|
{
|
|
RR *nrp;
|
|
SOA *soa;
|
|
Srv *srv;
|
|
Key *key;
|
|
Cert *cert;
|
|
Sig *sig;
|
|
Null *null;
|
|
Txt *t, *nt, **l;
|
|
|
|
assert(rp->magic == RRmagic);
|
|
nrp = rralloc(rp->type);
|
|
switch(rp->type){
|
|
case Tsoa:
|
|
soa = nrp->soa;
|
|
*nrp = *rp;
|
|
nrp->soa = soa;
|
|
*soa = *rp->soa;
|
|
soa->slaves = copyserverlist(rp->soa->slaves);
|
|
break;
|
|
case Tsrv:
|
|
srv = nrp->srv;
|
|
*nrp = *rp;
|
|
nrp->srv = srv;
|
|
*srv = *rp->srv;
|
|
break;
|
|
case Tkey:
|
|
key = nrp->key;
|
|
*nrp = *rp;
|
|
nrp->key = key;
|
|
*key = *rp->key;
|
|
key->data = emalloc(key->dlen);
|
|
memmove(key->data, rp->key->data, rp->key->dlen);
|
|
break;
|
|
case Tcert:
|
|
cert = nrp->cert;
|
|
*nrp = *rp;
|
|
nrp->cert = cert;
|
|
*cert = *rp->cert;
|
|
cert->data = emalloc(cert->dlen);
|
|
memmove(cert->data, rp->cert->data, rp->cert->dlen);
|
|
break;
|
|
case Tsig:
|
|
sig = nrp->sig;
|
|
*nrp = *rp;
|
|
nrp->sig = sig;
|
|
*sig = *rp->sig;
|
|
sig->data = emalloc(sig->dlen);
|
|
memmove(sig->data, rp->sig->data, rp->sig->dlen);
|
|
break;
|
|
case Tnull:
|
|
null = nrp->null;
|
|
*nrp = *rp;
|
|
nrp->null = null;
|
|
*null = *rp->null;
|
|
null->data = emalloc(null->dlen);
|
|
memmove(null->data, rp->null->data, rp->null->dlen);
|
|
break;
|
|
case Ttxt:
|
|
*nrp = *rp;
|
|
l = &nrp->txt;
|
|
*l = nil;
|
|
for(t = rp->txt; t != nil; t = t->next){
|
|
nt = emalloc(sizeof(*nt));
|
|
nt->p = estrdup(t->p);
|
|
nt->next = nil;
|
|
*l = nt;
|
|
l = &nt->next;
|
|
}
|
|
break;
|
|
default:
|
|
*nrp = *rp;
|
|
break;
|
|
}
|
|
nrp->pc = getcallerpc();
|
|
setmalloctag(nrp, nrp->pc);
|
|
nrp->cached = 0;
|
|
nrp->next = nil;
|
|
*last = nrp;
|
|
return &nrp->next;
|
|
}
|
|
|
|
/*
|
|
* lookup a resource record of a particular type and
|
|
* class attached to a domain name. Return copies.
|
|
*
|
|
* Priority ordering is:
|
|
* db authoritative
|
|
* not timed out network authoritative
|
|
* not timed out network unauthoritative
|
|
* unauthoritative db
|
|
*
|
|
* if flag NOneg is set, don't return negative cached entries.
|
|
* return nothing instead.
|
|
*/
|
|
RR*
|
|
rrlookup(DN *dp, int type, int flag)
|
|
{
|
|
RR *rp, *first, **last;
|
|
|
|
assert(dp->magic == DNmagic);
|
|
|
|
first = nil;
|
|
last = &first;
|
|
lock(&dnlock);
|
|
|
|
/* try for an authoritative db entry */
|
|
for(rp = dp->rr; rp; rp = rp->next){
|
|
assert(rp->magic == RRmagic && rp->cached);
|
|
if(rp->db)
|
|
if(rp->auth)
|
|
if(tsame(type, rp->type))
|
|
last = rrcopy(rp, last);
|
|
}
|
|
if(first)
|
|
goto out;
|
|
|
|
/* try for a living authoritative network entry */
|
|
for(rp = dp->rr; rp; rp = rp->next){
|
|
if(!rp->db)
|
|
if(rp->auth)
|
|
if((int32_t)(rp->expire - now) > 0)
|
|
if(tsame(type, rp->type)){
|
|
if(flag == NOneg && rp->negative)
|
|
goto out;
|
|
last = rrcopy(rp, last);
|
|
}
|
|
}
|
|
if(first)
|
|
goto out;
|
|
|
|
/* try for a living unauthoritative network entry */
|
|
for(rp = dp->rr; rp; rp = rp->next){
|
|
if(!rp->db)
|
|
if((int32_t)(rp->expire - now) > 0)
|
|
if(tsame(type, rp->type)){
|
|
if(flag == NOneg && rp->negative)
|
|
goto out;
|
|
last = rrcopy(rp, last);
|
|
}
|
|
}
|
|
if(first)
|
|
goto out;
|
|
|
|
/* try for an unauthoritative db entry */
|
|
for(rp = dp->rr; rp; rp = rp->next){
|
|
if(rp->db)
|
|
if(tsame(type, rp->type))
|
|
last = rrcopy(rp, last);
|
|
}
|
|
if(first)
|
|
goto out;
|
|
|
|
/* otherwise, settle for anything we got (except for negative caches) */
|
|
for(rp = dp->rr; rp; rp = rp->next)
|
|
if(tsame(type, rp->type)){
|
|
if(rp->negative)
|
|
goto out;
|
|
last = rrcopy(rp, last);
|
|
}
|
|
|
|
out:
|
|
unlock(&dnlock);
|
|
unique(first);
|
|
return first;
|
|
}
|
|
|
|
/*
|
|
* convert an ascii RR type name to its integer representation
|
|
*/
|
|
int
|
|
rrtype(char *atype)
|
|
{
|
|
int i;
|
|
|
|
for(i = 0; i <= Tall; i++)
|
|
if(rrtname[i] && strcmp(rrtname[i], atype) == 0)
|
|
return i;
|
|
|
|
/* make any a synonym for all */
|
|
if(strcmp(atype, "any") == 0)
|
|
return Tall;
|
|
else if(isascii(atype[0]) && isdigit(atype[0]))
|
|
return atoi(atype);
|
|
else
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* return 0 if not a supported rr type
|
|
*/
|
|
int
|
|
rrsupported(int type)
|
|
{
|
|
if(type < 0 || type >Tall)
|
|
return 0;
|
|
return rrtname[type] != nil;
|
|
}
|
|
|
|
/*
|
|
* compare 2 types
|
|
*/
|
|
int
|
|
tsame(int t1, int t2)
|
|
{
|
|
return t1 == t2 || t1 == Tall;
|
|
}
|
|
|
|
/*
|
|
* Add resource records to a list.
|
|
*/
|
|
RR*
|
|
rrcat(RR **start, RR *rp)
|
|
{
|
|
RR *olp, *nlp;
|
|
RR **last;
|
|
|
|
/* check for duplicates */
|
|
for (olp = *start; 0 && olp; olp = olp->next)
|
|
for (nlp = rp; nlp; nlp = nlp->next)
|
|
if (rrsame(nlp, olp))
|
|
dnslog("rrcat: duplicate RR: %R", nlp);
|
|
USED(olp);
|
|
|
|
last = start;
|
|
while(*last != nil)
|
|
last = &(*last)->next;
|
|
|
|
*last = rp;
|
|
return *start;
|
|
}
|
|
|
|
RR*
|
|
rrremfilter(RR **l, int (*filter)(RR*, void*), void *arg)
|
|
{
|
|
RR *first, *rp;
|
|
RR **nl;
|
|
|
|
first = nil;
|
|
nl = &first;
|
|
while(*l != nil){
|
|
rp = *l;
|
|
if((*filter)(rp, arg)){
|
|
*l = rp->next;
|
|
*nl = rp;
|
|
nl = &rp->next;
|
|
*nl = nil;
|
|
} else
|
|
l = &(*l)->next;
|
|
}
|
|
|
|
return first;
|
|
}
|
|
|
|
static int
|
|
filterneg(RR *rp, void* _1)
|
|
{
|
|
return rp->negative;
|
|
}
|
|
static int
|
|
filtertype(RR *rp, void *arg)
|
|
{
|
|
return rp->type == *((int*)arg);
|
|
}
|
|
static int
|
|
filterowner(RR *rp, void *arg)
|
|
{
|
|
return rp->owner == (DN*)arg;
|
|
}
|
|
|
|
/*
|
|
* remove negative cache rr's from an rr list
|
|
*/
|
|
RR*
|
|
rrremneg(RR **l)
|
|
{
|
|
return rrremfilter(l, filterneg, nil);
|
|
}
|
|
|
|
/*
|
|
* remove rr's of a particular type from an rr list
|
|
*/
|
|
RR*
|
|
rrremtype(RR **l, int type)
|
|
{
|
|
return rrremfilter(l, filtertype, &type);
|
|
}
|
|
|
|
/*
|
|
* remove rr's of a particular owner from an rr list
|
|
*/
|
|
RR*
|
|
rrremowner(RR **l, DN *owner)
|
|
{
|
|
return rrremfilter(l, filterowner, owner);
|
|
}
|
|
|
|
static char *
|
|
dnname(DN *dn)
|
|
{
|
|
return dn? dn->name: "<null>";
|
|
}
|
|
|
|
static char *
|
|
idnname(DN *dn, char *buf, int nbuf)
|
|
{
|
|
char *name;
|
|
|
|
name = dnname(dn);
|
|
if(idn2utf(name, buf, nbuf) != nil)
|
|
return buf;
|
|
return name;
|
|
}
|
|
|
|
/*
|
|
* print conversion for rr records
|
|
*/
|
|
int
|
|
rrfmt(Fmt *f)
|
|
{
|
|
int rv;
|
|
char *strp;
|
|
char buf[Domlen];
|
|
Fmt fstr;
|
|
RR *rp;
|
|
Server *s;
|
|
SOA *soa;
|
|
Srv *srv;
|
|
Txt *t;
|
|
|
|
fmtstrinit(&fstr);
|
|
|
|
rp = va_arg(f->args, RR*);
|
|
if(rp == nil){
|
|
fmtprint(&fstr, "<null>");
|
|
goto out;
|
|
}
|
|
|
|
fmtprint(&fstr, "%s %s", dnname(rp->owner),
|
|
rrname(rp->type, buf, sizeof buf));
|
|
|
|
if(rp->negative){
|
|
fmtprint(&fstr, "\tnegative - rcode %d", rp->negrcode);
|
|
goto out;
|
|
}
|
|
|
|
switch(rp->type){
|
|
case Thinfo:
|
|
fmtprint(&fstr, "\t%s %s", dnname(rp->cpu), dnname(rp->os));
|
|
break;
|
|
case Tcname:
|
|
case Tmb:
|
|
case Tmd:
|
|
case Tmf:
|
|
case Tns:
|
|
fmtprint(&fstr, "\t%s", dnname(rp->host));
|
|
break;
|
|
case Tmg:
|
|
case Tmr:
|
|
fmtprint(&fstr, "\t%s", dnname(rp->mb));
|
|
break;
|
|
case Tminfo:
|
|
fmtprint(&fstr, "\t%s %s", dnname(rp->mb), dnname(rp->rmb));
|
|
break;
|
|
case Tmx:
|
|
fmtprint(&fstr, "\t%lud %s", rp->pref, dnname(rp->host));
|
|
break;
|
|
case Ta:
|
|
case Taaaa:
|
|
fmtprint(&fstr, "\t%s", dnname(rp->ip));
|
|
break;
|
|
case Tptr:
|
|
fmtprint(&fstr, "\t%s", dnname(rp->ptr));
|
|
break;
|
|
case Tsoa:
|
|
soa = rp->soa;
|
|
fmtprint(&fstr, "\t%s %s %lud %lud %lud %lud %lud",
|
|
dnname(rp->host), dnname(rp->rmb),
|
|
(soa? soa->serial: 0),
|
|
(soa? soa->refresh: 0), (soa? soa->retry: 0),
|
|
(soa? soa->expire: 0), (soa? soa->minttl: 0));
|
|
if (soa)
|
|
for(s = soa->slaves; s != nil; s = s->next)
|
|
fmtprint(&fstr, " %s", s->name);
|
|
break;
|
|
case Tsrv:
|
|
srv = rp->srv;
|
|
fmtprint(&fstr, "\t%ud %ud %ud %s",
|
|
(srv? srv->pri: 0), (srv? srv->weight: 0),
|
|
rp->port, dnname(rp->host));
|
|
break;
|
|
case Tnull:
|
|
if (rp->null == nil)
|
|
fmtprint(&fstr, "\t<null>");
|
|
else
|
|
fmtprint(&fstr, "\t%.*H", rp->null->dlen,
|
|
rp->null->data);
|
|
break;
|
|
case Ttxt:
|
|
fmtprint(&fstr, "\t");
|
|
for(t = rp->txt; t != nil; t = t->next)
|
|
fmtprint(&fstr, "%s", t->p);
|
|
break;
|
|
case Trp:
|
|
fmtprint(&fstr, "\t%s %s", dnname(rp->rmb), dnname(rp->rp));
|
|
break;
|
|
case Tkey:
|
|
if (rp->key == nil)
|
|
fmtprint(&fstr, "\t<null> <null> <null>");
|
|
else
|
|
fmtprint(&fstr, "\t%d %d %d", rp->key->flags,
|
|
rp->key->proto, rp->key->alg);
|
|
break;
|
|
case Tsig:
|
|
if (rp->sig == nil)
|
|
fmtprint(&fstr,
|
|
"\t<null> <null> <null> <null> <null> <null> <null> <null>");
|
|
else
|
|
fmtprint(&fstr, "\t%d %d %d %lud %lud %lud %d %s",
|
|
rp->sig->type, rp->sig->alg, rp->sig->labels,
|
|
rp->sig->ttl, rp->sig->exp, rp->sig->incep,
|
|
rp->sig->tag, dnname(rp->sig->signer));
|
|
break;
|
|
case Tcert:
|
|
if (rp->cert == nil)
|
|
fmtprint(&fstr, "\t<null> <null> <null>");
|
|
else
|
|
fmtprint(&fstr, "\t%d %d %d",
|
|
rp->cert->type, rp->cert->tag, rp->cert->alg);
|
|
break;
|
|
}
|
|
out:
|
|
strp = fmtstrflush(&fstr);
|
|
rv = fmtstrcpy(f, strp);
|
|
free(strp);
|
|
return rv;
|
|
}
|
|
|
|
/*
|
|
* print conversion for rr records in attribute value form
|
|
*/
|
|
int
|
|
rravfmt(Fmt *f)
|
|
{
|
|
int rv, quote;
|
|
char buf[Domlen], *strp;
|
|
Fmt fstr;
|
|
RR *rp;
|
|
Server *s;
|
|
SOA *soa;
|
|
Srv *srv;
|
|
Txt *t;
|
|
|
|
fmtstrinit(&fstr);
|
|
|
|
rp = va_arg(f->args, RR*);
|
|
if(rp == nil){
|
|
fmtprint(&fstr, "<null>");
|
|
goto out;
|
|
}
|
|
|
|
if(rp->type == Tptr)
|
|
fmtprint(&fstr, "ptr=%s", dnname(rp->owner));
|
|
else
|
|
fmtprint(&fstr, "dom=%s", idnname(rp->owner, buf, sizeof(buf)));
|
|
|
|
switch(rp->type){
|
|
case Thinfo:
|
|
fmtprint(&fstr, " cpu=%s os=%s",
|
|
idnname(rp->cpu, buf, sizeof(buf)),
|
|
idnname(rp->os, buf, sizeof(buf)));
|
|
break;
|
|
case Tcname:
|
|
fmtprint(&fstr, " cname=%s", idnname(rp->host, buf, sizeof(buf)));
|
|
break;
|
|
case Tmb:
|
|
case Tmd:
|
|
case Tmf:
|
|
fmtprint(&fstr, " mbox=%s", idnname(rp->host, buf, sizeof(buf)));
|
|
break;
|
|
case Tns:
|
|
fmtprint(&fstr, " ns=%s", idnname(rp->host, buf, sizeof(buf)));
|
|
break;
|
|
case Tmg:
|
|
case Tmr:
|
|
fmtprint(&fstr, " mbox=%s", idnname(rp->mb, buf, sizeof(buf)));
|
|
break;
|
|
case Tminfo:
|
|
fmtprint(&fstr, " mbox=%s mbox=%s",
|
|
idnname(rp->mb, buf, sizeof(buf)),
|
|
idnname(rp->rmb, buf, sizeof(buf)));
|
|
break;
|
|
case Tmx:
|
|
fmtprint(&fstr, " pref=%lud mx=%s", rp->pref,
|
|
idnname(rp->host, buf, sizeof(buf)));
|
|
break;
|
|
case Ta:
|
|
case Taaaa:
|
|
fmtprint(&fstr, " ip=%s", dnname(rp->ip));
|
|
break;
|
|
case Tptr:
|
|
fmtprint(&fstr, " dom=%s", dnname(rp->ptr));
|
|
break;
|
|
case Tsoa:
|
|
soa = rp->soa;
|
|
fmtprint(&fstr,
|
|
" ns=%s mbox=%s serial=%lud refresh=%lud retry=%lud expire=%lud ttl=%lud",
|
|
idnname(rp->host, buf, sizeof(buf)),
|
|
idnname(rp->rmb, buf, sizeof(buf)),
|
|
(soa? soa->serial: 0),
|
|
(soa? soa->refresh: 0), (soa? soa->retry: 0),
|
|
(soa? soa->expire: 0), (soa? soa->minttl: 0));
|
|
for(s = soa->slaves; s != nil; s = s->next)
|
|
fmtprint(&fstr, " dnsslave=%s", s->name);
|
|
break;
|
|
case Tsrv:
|
|
srv = rp->srv;
|
|
fmtprint(&fstr, " pri=%ud weight=%ud port=%ud target=%s",
|
|
(srv? srv->pri: 0), (srv? srv->weight: 0),
|
|
rp->port, idnname(rp->host, buf, sizeof(buf)));
|
|
break;
|
|
case Tnull:
|
|
if (rp->null == nil)
|
|
fmtprint(&fstr, " null=<null>");
|
|
else
|
|
fmtprint(&fstr, " null=%.*H", rp->null->dlen,
|
|
rp->null->data);
|
|
break;
|
|
case Ttxt:
|
|
fmtprint(&fstr, " txt=");
|
|
quote = 0;
|
|
for(t = rp->txt; t != nil; t = t->next)
|
|
if(strchr(t->p, ' '))
|
|
quote = 1;
|
|
if(quote)
|
|
fmtprint(&fstr, "\"");
|
|
for(t = rp->txt; t != nil; t = t->next)
|
|
fmtprint(&fstr, "%s", t->p);
|
|
if(quote)
|
|
fmtprint(&fstr, "\"");
|
|
break;
|
|
case Trp:
|
|
fmtprint(&fstr, " rp=%s txt=%s",
|
|
idnname(rp->rmb, buf, sizeof(buf)),
|
|
idnname(rp->rp, buf, sizeof(buf)));
|
|
break;
|
|
case Tkey:
|
|
if (rp->key == nil)
|
|
fmtprint(&fstr, " flags=<null> proto=<null> alg=<null>");
|
|
else
|
|
fmtprint(&fstr, " flags=%d proto=%d alg=%d",
|
|
rp->key->flags, rp->key->proto, rp->key->alg);
|
|
break;
|
|
case Tsig:
|
|
if (rp->sig == nil)
|
|
fmtprint(&fstr,
|
|
" type=<null> alg=<null> labels=<null> ttl=<null> exp=<null> incep=<null> tag=<null> signer=<null>");
|
|
else
|
|
fmtprint(&fstr,
|
|
" type=%d alg=%d labels=%d ttl=%lud exp=%lud incep=%lud tag=%d signer=%s",
|
|
rp->sig->type, rp->sig->alg, rp->sig->labels,
|
|
rp->sig->ttl, rp->sig->exp, rp->sig->incep,
|
|
rp->sig->tag, idnname(rp->sig->signer, buf, sizeof(buf)));
|
|
break;
|
|
case Tcert:
|
|
if (rp->cert == nil)
|
|
fmtprint(&fstr, " type=<null> tag=<null> alg=<null>");
|
|
else
|
|
fmtprint(&fstr, " type=%d tag=%d alg=%d",
|
|
rp->cert->type, rp->cert->tag, rp->cert->alg);
|
|
break;
|
|
}
|
|
out:
|
|
strp = fmtstrflush(&fstr);
|
|
rv = fmtstrcpy(f, strp);
|
|
free(strp);
|
|
return rv;
|
|
}
|
|
|
|
void
|
|
warning(char *fmt, ...)
|
|
{
|
|
char dnserr[256];
|
|
va_list arg;
|
|
|
|
va_start(arg, fmt);
|
|
vseprint(dnserr, dnserr+sizeof(dnserr), fmt, arg);
|
|
va_end(arg);
|
|
syslog(1, logfile, dnserr); /* on console too */
|
|
}
|
|
|
|
void
|
|
dnslog(char *fmt, ...)
|
|
{
|
|
char dnserr[256];
|
|
va_list arg;
|
|
|
|
va_start(arg, fmt);
|
|
vseprint(dnserr, dnserr+sizeof(dnserr), fmt, arg);
|
|
va_end(arg);
|
|
syslog(0, logfile, dnserr);
|
|
}
|
|
|
|
/*
|
|
* based on libthread's threadsetname, but drags in less library code.
|
|
* actually just sets the arguments displayed.
|
|
*/
|
|
void
|
|
procsetname(char *fmt, ...)
|
|
{
|
|
int fd;
|
|
char *cmdname;
|
|
char buf[128];
|
|
va_list arg;
|
|
|
|
va_start(arg, fmt);
|
|
cmdname = vsmprint(fmt, arg);
|
|
va_end(arg);
|
|
if (cmdname == nil)
|
|
return;
|
|
snprint(buf, sizeof buf, "#p/%d/args", getpid());
|
|
if((fd = open(buf, OWRITE)) >= 0){
|
|
write(fd, cmdname, strlen(cmdname)+1);
|
|
close(fd);
|
|
}
|
|
free(cmdname);
|
|
}
|
|
|
|
/*
|
|
* create a slave process to handle a request to avoid one request blocking
|
|
* another
|
|
*/
|
|
void
|
|
slave(Request *req)
|
|
{
|
|
int ppid, procs;
|
|
|
|
if(req->isslave)
|
|
return; /* we're already a slave process */
|
|
|
|
/*
|
|
* These calls to putactivity cannot block.
|
|
* After getactivity(), the current process is counted
|
|
* twice in dnvars.active (one will pass to the child).
|
|
* If putactivity tries to wait for dnvars.active == 0,
|
|
* it will never happen.
|
|
*/
|
|
|
|
/* limit parallelism */
|
|
procs = getactivity(req, 1);
|
|
if(procs > stats.slavehiwat)
|
|
stats.slavehiwat = procs;
|
|
if(procs > Maxactive){
|
|
if(traceactivity)
|
|
dnslog("[%d] too much activity", getpid());
|
|
putactivity(1);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* parent returns to main loop, child does the work.
|
|
* don't change note group.
|
|
*/
|
|
ppid = getpid();
|
|
switch(rfork(RFPROC|RFMEM|RFNOWAIT)){
|
|
case -1:
|
|
putactivity(1);
|
|
break;
|
|
case 0:
|
|
procsetname("request slave of pid %d", ppid);
|
|
if(traceactivity)
|
|
dnslog("[%d] take activity from %d", getpid(), ppid);
|
|
req->isslave = 1; /* why not `= getpid()'? */
|
|
break;
|
|
default:
|
|
/*
|
|
* this relies on rfork producing separate, initially-identical
|
|
* stacks, thus giving us two copies of `req', one in each
|
|
* process.
|
|
*/
|
|
alarm(0);
|
|
longjmp(req->mret, 1);
|
|
}
|
|
}
|
|
|
|
static int
|
|
rrequiv(RR *r1, RR *r2)
|
|
{
|
|
return r1->owner == r2->owner
|
|
&& r1->type == r2->type
|
|
&& r1->arg0 == r2->arg0
|
|
&& r1->arg1 == r2->arg1;
|
|
}
|
|
|
|
void
|
|
unique(RR *rp)
|
|
{
|
|
RR **l, *nrp;
|
|
|
|
for(; rp; rp = rp->next){
|
|
l = &rp->next;
|
|
for(nrp = *l; nrp; nrp = *l)
|
|
if(rrequiv(rp, nrp)){
|
|
*l = nrp->next;
|
|
rrfree(nrp);
|
|
} else
|
|
l = &nrp->next;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* true if second domain is subsumed by the first
|
|
*/
|
|
int
|
|
subsume(char *higher, char *lower)
|
|
{
|
|
int hn, ln;
|
|
|
|
ln = strlen(lower);
|
|
hn = strlen(higher);
|
|
if (ln < hn || cistrcmp(lower + ln - hn, higher) != 0 ||
|
|
ln > hn && hn != 0 && lower[ln - hn - 1] != '.')
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* randomize the order we return items to provide some
|
|
* load balancing for servers.
|
|
*
|
|
* only randomize the first class of entries
|
|
*/
|
|
RR*
|
|
randomize(RR *rp)
|
|
{
|
|
RR *first, *last, *x, *base;
|
|
uint32_t n;
|
|
|
|
if(rp == nil || rp->next == nil)
|
|
return rp;
|
|
|
|
/* just randomize addresses, mx's and ns's */
|
|
for(x = rp; x; x = x->next)
|
|
if(x->type != Ta && x->type != Taaaa &&
|
|
x->type != Tmx && x->type != Tns)
|
|
return rp;
|
|
|
|
base = rp;
|
|
|
|
n = rand();
|
|
last = first = nil;
|
|
while(rp != nil){
|
|
/* stop randomizing if we've moved past our class */
|
|
if(base->auth != rp->auth || base->db != rp->db){
|
|
last->next = rp;
|
|
break;
|
|
}
|
|
|
|
/* unchain */
|
|
x = rp;
|
|
rp = x->next;
|
|
x->next = nil;
|
|
|
|
if(n&1){
|
|
/* add to tail */
|
|
if(last == nil)
|
|
first = x;
|
|
else
|
|
last->next = x;
|
|
last = x;
|
|
} else {
|
|
/* add to head */
|
|
if(last == nil)
|
|
last = x;
|
|
x->next = first;
|
|
first = x;
|
|
}
|
|
|
|
/* reroll the dice */
|
|
n >>= 1;
|
|
}
|
|
|
|
return first;
|
|
}
|
|
|
|
static int
|
|
sencodefmt(Fmt *f)
|
|
{
|
|
int i, len, ilen, rv;
|
|
char *out, *buf;
|
|
uint8_t *b;
|
|
char obuf[64]; /* rsc optimization */
|
|
|
|
if(!(f->flags&FmtPrec) || f->prec < 1)
|
|
goto error;
|
|
|
|
b = va_arg(f->args, uint8_t*);
|
|
if(b == nil)
|
|
goto error;
|
|
|
|
/* if it's a printable, go for it */
|
|
len = f->prec;
|
|
for(i = 0; i < len; i++)
|
|
if(!isprint(b[i]))
|
|
break;
|
|
if(i == len){
|
|
if(len >= sizeof obuf)
|
|
len = sizeof(obuf)-1;
|
|
memmove(obuf, b, len);
|
|
obuf[len] = 0;
|
|
fmtstrcpy(f, obuf);
|
|
return 0;
|
|
}
|
|
|
|
ilen = f->prec;
|
|
f->prec = 0;
|
|
f->flags &= ~FmtPrec;
|
|
len = 2*ilen + 1;
|
|
if(len > sizeof(obuf)){
|
|
buf = malloc(len);
|
|
if(buf == nil)
|
|
goto error;
|
|
} else
|
|
buf = obuf;
|
|
|
|
/* convert */
|
|
out = buf;
|
|
rv = enc16(out, len, b, ilen);
|
|
if(rv < 0)
|
|
goto error;
|
|
|
|
fmtstrcpy(f, buf);
|
|
if(buf != obuf)
|
|
free(buf);
|
|
return 0;
|
|
|
|
error:
|
|
return fmtstrcpy(f, "<encodefmt>");
|
|
}
|
|
|
|
void*
|
|
emalloc(int size)
|
|
{
|
|
char *x;
|
|
|
|
x = mallocz(size, 1);
|
|
if(x == nil)
|
|
abort();
|
|
setmalloctag(x, getcallerpc());
|
|
return x;
|
|
}
|
|
|
|
char*
|
|
estrdup(char *s)
|
|
{
|
|
int size;
|
|
char *p;
|
|
|
|
size = strlen(s);
|
|
p = mallocz(size+1, 0);
|
|
if(p == nil)
|
|
abort();
|
|
memmove(p, s, size);
|
|
p[size] = 0;
|
|
setmalloctag(p, getcallerpc());
|
|
return p;
|
|
}
|
|
|
|
/*
|
|
* create a pointer record
|
|
*/
|
|
static RR*
|
|
mkptr(DN *dp, char *ptr, uint32_t ttl)
|
|
{
|
|
DN *ipdp;
|
|
RR *rp;
|
|
|
|
ipdp = dnlookup(ptr, Cin, 1);
|
|
|
|
rp = rralloc(Tptr);
|
|
rp->ptr = dp;
|
|
rp->owner = ipdp;
|
|
rp->db = 1;
|
|
if(ttl)
|
|
rp->ttl = ttl;
|
|
return rp;
|
|
}
|
|
|
|
void bytes2nibbles(uint8_t *nibbles, uint8_t *bytes, int nbytes);
|
|
|
|
/*
|
|
* look for all ip addresses in this network and make
|
|
* pointer records for them.
|
|
*/
|
|
void
|
|
dnptr(uint8_t *net, uint8_t *mask, char *dom, int forwtype, int subdoms, int ttl)
|
|
{
|
|
int i, j, len;
|
|
char *p, *e;
|
|
char ptr[Domlen];
|
|
uint8_t *ipp;
|
|
uint8_t ip[IPaddrlen], nnet[IPaddrlen];
|
|
uint8_t nibip[IPaddrlen*2];
|
|
DN *dp;
|
|
RR *rp, *nrp, *first, **l;
|
|
|
|
l = &first;
|
|
first = nil;
|
|
for(i = 0; i < HTLEN; i++)
|
|
for(dp = ht[i]; dp; dp = dp->next)
|
|
for(rp = dp->rr; rp; rp = rp->next){
|
|
if(rp->type != forwtype || rp->negative)
|
|
continue;
|
|
parseip(ip, rp->ip->name);
|
|
maskip(ip, mask, nnet);
|
|
if(ipcmp(net, nnet) != 0)
|
|
continue;
|
|
|
|
ipp = ip;
|
|
len = IPaddrlen;
|
|
if (forwtype == Taaaa) {
|
|
bytes2nibbles(nibip, ip, IPaddrlen);
|
|
ipp = nibip;
|
|
len = 2*IPaddrlen;
|
|
}
|
|
|
|
p = ptr;
|
|
e = ptr+sizeof(ptr);
|
|
for(j = len - 1; j >= len - subdoms; j--)
|
|
p = seprint(p, e, (forwtype == Ta?
|
|
"%d.": "%x."), ipp[j]);
|
|
seprint(p, e, "%s", dom);
|
|
|
|
nrp = mkptr(dp, ptr, ttl);
|
|
*l = nrp;
|
|
l = &nrp->next;
|
|
}
|
|
|
|
for(rp = first; rp != nil; rp = nrp){
|
|
nrp = rp->next;
|
|
rp->next = nil;
|
|
dp = rp->owner;
|
|
rrattach(rp, Authoritative);
|
|
dnagenever(dp);
|
|
}
|
|
}
|
|
|
|
void
|
|
addserver(Server **l, char *name)
|
|
{
|
|
Server *s;
|
|
int n;
|
|
|
|
while(*l)
|
|
l = &(*l)->next;
|
|
n = strlen(name);
|
|
s = malloc(sizeof(Server)+n+1);
|
|
if(s == nil)
|
|
return;
|
|
s->name = (char*)(s+1);
|
|
memmove(s->name, name, n);
|
|
s->name[n] = 0;
|
|
s->next = nil;
|
|
*l = s;
|
|
}
|
|
|
|
Server*
|
|
copyserverlist(Server *s)
|
|
{
|
|
Server *ns;
|
|
|
|
for(ns = nil; s != nil; s = s->next)
|
|
addserver(&ns, s->name);
|
|
return ns;
|
|
}
|
|
|
|
|
|
/* from here down is copied to ip/snoopy/dns.c periodically to update it */
|
|
|
|
/*
|
|
* convert an integer RR type to it's ascii name
|
|
*/
|
|
char*
|
|
rrname(int type, char *buf, int len)
|
|
{
|
|
char *t;
|
|
|
|
t = nil;
|
|
if(type >= 0 && type <= Tall)
|
|
t = rrtname[type];
|
|
if(t==nil){
|
|
snprint(buf, len, "%d", type);
|
|
t = buf;
|
|
}
|
|
return t;
|
|
}
|
|
|
|
/*
|
|
* free a list of resource records and any related structs
|
|
*/
|
|
void
|
|
rrfreelist(RR *rp)
|
|
{
|
|
RR *next;
|
|
|
|
for(; rp; rp = next){
|
|
next = rp->next;
|
|
rrfree(rp);
|
|
}
|
|
}
|
|
|
|
void
|
|
freeserverlist(Server *s)
|
|
{
|
|
Server *next;
|
|
|
|
for(; s != nil; s = next){
|
|
next = s->next;
|
|
memset(s, 0, sizeof *s); /* cause trouble */
|
|
free(s);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* allocate a resource record of a given type
|
|
*/
|
|
RR*
|
|
rralloc(int type)
|
|
{
|
|
RR *rp;
|
|
|
|
rp = emalloc(sizeof(*rp));
|
|
rp->magic = RRmagic;
|
|
rp->pc = getcallerpc();
|
|
rp->type = type;
|
|
if (rp->type != type)
|
|
dnslog("rralloc: bogus type %d", type);
|
|
setmalloctag(rp, rp->pc);
|
|
switch(type){
|
|
case Tsoa:
|
|
rp->soa = emalloc(sizeof(*rp->soa));
|
|
rp->soa->slaves = nil;
|
|
setmalloctag(rp->soa, rp->pc);
|
|
break;
|
|
case Tsrv:
|
|
rp->srv = emalloc(sizeof(*rp->srv));
|
|
setmalloctag(rp->srv, rp->pc);
|
|
break;
|
|
case Tkey:
|
|
rp->key = emalloc(sizeof(*rp->key));
|
|
setmalloctag(rp->key, rp->pc);
|
|
break;
|
|
case Tcert:
|
|
rp->cert = emalloc(sizeof(*rp->cert));
|
|
setmalloctag(rp->cert, rp->pc);
|
|
break;
|
|
case Tsig:
|
|
rp->sig = emalloc(sizeof(*rp->sig));
|
|
setmalloctag(rp->sig, rp->pc);
|
|
break;
|
|
case Tnull:
|
|
rp->null = emalloc(sizeof(*rp->null));
|
|
setmalloctag(rp->null, rp->pc);
|
|
break;
|
|
}
|
|
rp->ttl = 0;
|
|
rp->expire = 0;
|
|
rp->next = 0;
|
|
return rp;
|
|
}
|
|
|
|
/*
|
|
* free a resource record and any related structs
|
|
*/
|
|
void
|
|
rrfree(RR *rp)
|
|
{
|
|
Txt *t;
|
|
|
|
assert(rp->magic == RRmagic && !rp->cached);
|
|
|
|
switch(rp->type){
|
|
case Tsoa:
|
|
freeserverlist(rp->soa->slaves);
|
|
memset(rp->soa, 0, sizeof *rp->soa); /* cause trouble */
|
|
free(rp->soa);
|
|
break;
|
|
case Tsrv:
|
|
memset(rp->srv, 0, sizeof *rp->srv); /* cause trouble */
|
|
free(rp->srv);
|
|
break;
|
|
case Tkey:
|
|
free(rp->key->data);
|
|
memset(rp->key, 0, sizeof *rp->key); /* cause trouble */
|
|
free(rp->key);
|
|
break;
|
|
case Tcert:
|
|
free(rp->cert->data);
|
|
memset(rp->cert, 0, sizeof *rp->cert); /* cause trouble */
|
|
free(rp->cert);
|
|
break;
|
|
case Tsig:
|
|
free(rp->sig->data);
|
|
memset(rp->sig, 0, sizeof *rp->sig); /* cause trouble */
|
|
free(rp->sig);
|
|
break;
|
|
case Tnull:
|
|
free(rp->null->data);
|
|
memset(rp->null, 0, sizeof *rp->null); /* cause trouble */
|
|
free(rp->null);
|
|
break;
|
|
case Ttxt:
|
|
while(t = rp->txt){
|
|
rp->txt = t->next;
|
|
free(t->p);
|
|
memset(t, 0, sizeof *t); /* cause trouble */
|
|
free(t);
|
|
}
|
|
break;
|
|
}
|
|
|
|
memset(rp, 0, sizeof *rp); /* cause trouble */
|
|
rp->magic = ~RRmagic;
|
|
free(rp);
|
|
}
|