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#include "error.h"
#include "roots.h"
#include "log.h"
#include "case.h"
#include "cache.h"
#include "byte.h"
#include "dns.h"
#include "uint64.h"
#include "uint32.h"
#include "uint16.h"
#include "dd.h"
#include "alloc.h"
#include "response.h"
#include "query.h"
static int flagforwardonly = 0;
void query_forwardonly(void)
{
flagforwardonly = 1;
}
static void cachegeneric(const char type[2],const char *d,const char *data,unsigned int datalen,uint32 ttl)
{
unsigned int len;
char key[257];
len = dns_domain_length(d);
if (len > 255) return;
byte_copy(key,2,type);
byte_copy(key + 2,len,d);
case_lowerb(key + 2,len);
cache_set(key,len + 2,data,datalen,ttl);
}
static char save_buf[8192];
static unsigned int save_len;
static unsigned int save_ok;
static void save_start(void)
{
save_len = 0;
save_ok = 1;
}
static void save_data(const char *buf,unsigned int len)
{
if (!save_ok) return;
if (len > (sizeof save_buf) - save_len) { save_ok = 0; return; }
byte_copy(save_buf + save_len,len,buf);
save_len += len;
}
static void save_finish(const char type[2],const char *d,uint32 ttl)
{
if (!save_ok) return;
cachegeneric(type,d,save_buf,save_len,ttl);
}
static int typematch(const char rtype[2],const char qtype[2])
{
return byte_equal(qtype,2,rtype) || byte_equal(qtype,2,DNS_T_ANY);
}
static uint32 ttlget(char buf[4])
{
uint32 ttl;
uint32_unpack_big(buf,&ttl);
if (ttl > 1000000000) return 0;
if (ttl > 604800) return 604800;
return ttl;
}
static void cleanup(struct query *z)
{
int j;
int k;
dns_transmit_free(&z->dt);
for (j = 0;j < QUERY_MAXALIAS;++j)
dns_domain_free(&z->alias[j]);
for (j = 0;j < QUERY_MAXLEVEL;++j) {
dns_domain_free(&z->name[j]);
for (k = 0;k < QUERY_MAXNS;++k)
dns_domain_free(&z->ns[j][k]);
}
}
static int rqa(struct query *z)
{
int i;
for (i = QUERY_MAXALIAS - 1;i >= 0;--i)
if (z->alias[i]) {
if (!response_query(z->alias[i],z->type,z->class)) return 0;
while (i > 0) {
if (!response_cname(z->alias[i],z->alias[i - 1],z->aliasttl[i])) return 0;
--i;
}
if (!response_cname(z->alias[0],z->name[0],z->aliasttl[0])) return 0;
return 1;
}
if (!response_query(z->name[0],z->type,z->class)) return 0;
return 1;
}
static int globalip(char *d,char ip[4])
{
if (dns_domain_equal(d,"\011localhost\0")) {
byte_copy(ip,4,"\177\0\0\1");
return 1;
}
if (dd(d,"",ip) == 4) return 1;
return 0;
}
static char *t1 = 0;
static char *t2 = 0;
static char *t3 = 0;
static char *cname = 0;
static char *referral = 0;
static unsigned int *records = 0;
static int smaller(char *buf,unsigned int len,unsigned int pos1,unsigned int pos2)
{
char header1[12];
char header2[12];
int r;
unsigned int len1;
unsigned int len2;
pos1 = dns_packet_getname(buf,len,pos1,&t1);
dns_packet_copy(buf,len,pos1,header1,10);
pos2 = dns_packet_getname(buf,len,pos2,&t2);
dns_packet_copy(buf,len,pos2,header2,10);
r = byte_diff(header1,4,header2);
if (r < 0) return 1;
if (r > 0) return 0;
len1 = dns_domain_length(t1);
len2 = dns_domain_length(t2);
if (len1 < len2) return 1;
if (len1 > len2) return 0;
r = case_diffb(t1,len1,t2);
if (r < 0) return 1;
if (r > 0) return 0;
if (pos1 < pos2) return 1;
return 0;
}
static int doit(struct query *z,int state)
{
char key[257];
char *cached;
unsigned int cachedlen;
char *buf;
unsigned int len;
const char *whichserver;
char header[12];
char misc[20];
unsigned int rcode;
unsigned int posanswers;
uint16 numanswers;
unsigned int posauthority;
uint16 numauthority;
unsigned int posglue;
uint16 numglue;
unsigned int pos;
unsigned int pos2;
uint16 datalen;
char *control;
char *d;
const char *dtype;
unsigned int dlen;
int flagout;
int flagcname;
int flagreferral;
int flagsoa;
uint32 ttl;
uint32 soattl;
uint32 cnamettl;
int i;
int j;
int k;
int p;
int q;
errno = error_io;
if (state == 1) goto HAVEPACKET;
if (state == -1) {
log_servfail(z->name[z->level]);
goto SERVFAIL;
}
NEWNAME:
if (++z->loop == 100) goto DIE;
d = z->name[z->level];
dtype = z->level ? DNS_T_A : z->type;
dlen = dns_domain_length(d);
if (globalip(d,misc)) {
if (z->level) {
for (k = 0;k < 64;k += 4)
if (byte_equal(z->servers[z->level - 1] + k,4,"\0\0\0\0")) {
byte_copy(z->servers[z->level - 1] + k,4,misc);
break;
}
goto LOWERLEVEL;
}
if (!rqa(z)) goto DIE;
if (typematch(DNS_T_A,dtype)) {
if (!response_rstart(d,DNS_T_A,655360)) goto DIE;
if (!response_addbytes(misc,4)) goto DIE;
response_rfinish(RESPONSE_ANSWER);
}
cleanup(z);
return 1;
}
if (dns_domain_equal(d,"\0011\0010\0010\003127\7in-addr\4arpa\0")) {
if (z->level) goto LOWERLEVEL;
if (!rqa(z)) goto DIE;
if (typematch(DNS_T_PTR,dtype)) {
if (!response_rstart(d,DNS_T_PTR,655360)) goto DIE;
if (!response_addname("\011localhost\0")) goto DIE;
response_rfinish(RESPONSE_ANSWER);
}
cleanup(z);
log_stats();
return 1;
}
if (dlen <= 255) {
byte_copy(key,2,DNS_T_ANY);
byte_copy(key + 2,dlen,d);
case_lowerb(key + 2,dlen);
cached = cache_get(key,dlen + 2,&cachedlen,&ttl);
if (cached) {
log_cachednxdomain(d);
goto NXDOMAIN;
}
byte_copy(key,2,DNS_T_CNAME);
cached = cache_get(key,dlen + 2,&cachedlen,&ttl);
if (cached) {
if (typematch(DNS_T_CNAME,dtype)) {
log_cachedanswer(d,DNS_T_CNAME);
if (!rqa(z)) goto DIE;
if (!response_cname(z->name[0],cached,ttl)) goto DIE;
cleanup(z);
return 1;
}
log_cachedcname(d,cached);
if (!dns_domain_copy(&cname,cached)) goto DIE;
goto CNAME;
}
if (typematch(DNS_T_NS,dtype)) {
byte_copy(key,2,DNS_T_NS);
cached = cache_get(key,dlen + 2,&cachedlen,&ttl);
if (cached && (cachedlen || byte_diff(dtype,2,DNS_T_ANY))) {
log_cachedanswer(d,DNS_T_NS);
if (!rqa(z)) goto DIE;
pos = 0;
while (pos = dns_packet_getname(cached,cachedlen,pos,&t2)) {
if (!response_rstart(d,DNS_T_NS,ttl)) goto DIE;
if (!response_addname(t2)) goto DIE;
response_rfinish(RESPONSE_ANSWER);
}
cleanup(z);
return 1;
}
}
if (typematch(DNS_T_PTR,dtype)) {
byte_copy(key,2,DNS_T_PTR);
cached = cache_get(key,dlen + 2,&cachedlen,&ttl);
if (cached && (cachedlen || byte_diff(dtype,2,DNS_T_ANY))) {
log_cachedanswer(d,DNS_T_PTR);
if (!rqa(z)) goto DIE;
pos = 0;
while (pos = dns_packet_getname(cached,cachedlen,pos,&t2)) {
if (!response_rstart(d,DNS_T_PTR,ttl)) goto DIE;
if (!response_addname(t2)) goto DIE;
response_rfinish(RESPONSE_ANSWER);
}
cleanup(z);
return 1;
}
}
if (typematch(DNS_T_MX,dtype)) {
byte_copy(key,2,DNS_T_MX);
cached = cache_get(key,dlen + 2,&cachedlen,&ttl);
if (cached && (cachedlen || byte_diff(dtype,2,DNS_T_ANY))) {
log_cachedanswer(d,DNS_T_MX);
if (!rqa(z)) goto DIE;
pos = 0;
while (pos = dns_packet_copy(cached,cachedlen,pos,misc,2)) {
pos = dns_packet_getname(cached,cachedlen,pos,&t2);
if (!pos) break;
if (!response_rstart(d,DNS_T_MX,ttl)) goto DIE;
if (!response_addbytes(misc,2)) goto DIE;
if (!response_addname(t2)) goto DIE;
response_rfinish(RESPONSE_ANSWER);
}
cleanup(z);
return 1;
}
}
if (typematch(DNS_T_A,dtype)) {
byte_copy(key,2,DNS_T_A);
cached = cache_get(key,dlen + 2,&cachedlen,&ttl);
if (cached && (cachedlen || byte_diff(dtype,2,DNS_T_ANY))) {
if (z->level) {
log_cachedanswer(d,DNS_T_A);
while (cachedlen >= 4) {
for (k = 0;k < 64;k += 4)
if (byte_equal(z->servers[z->level - 1] + k,4,"\0\0\0\0")) {
byte_copy(z->servers[z->level - 1] + k,4,cached);
break;
}
cached += 4;
cachedlen -= 4;
}
goto LOWERLEVEL;
}
log_cachedanswer(d,DNS_T_A);
if (!rqa(z)) goto DIE;
while (cachedlen >= 4) {
if (!response_rstart(d,DNS_T_A,ttl)) goto DIE;
if (!response_addbytes(cached,4)) goto DIE;
response_rfinish(RESPONSE_ANSWER);
cached += 4;
cachedlen -= 4;
}
cleanup(z);
return 1;
}
}
if (!typematch(DNS_T_ANY,dtype) && !typematch(DNS_T_AXFR,dtype) && !typematch(DNS_T_CNAME,dtype) && !typematch(DNS_T_NS,dtype) && !typematch(DNS_T_PTR,dtype) && !typematch(DNS_T_A,dtype) && !typematch(DNS_T_MX,dtype)) {
byte_copy(key,2,dtype);
cached = cache_get(key,dlen + 2,&cachedlen,&ttl);
if (cached && (cachedlen || byte_diff(dtype,2,DNS_T_ANY))) {
log_cachedanswer(d,dtype);
if (!rqa(z)) goto DIE;
while (cachedlen >= 2) {
uint16_unpack_big(cached,&datalen);
cached += 2;
cachedlen -= 2;
if (datalen > cachedlen) goto DIE;
if (!response_rstart(d,dtype,ttl)) goto DIE;
if (!response_addbytes(cached,datalen)) goto DIE;
response_rfinish(RESPONSE_ANSWER);
cached += datalen;
cachedlen -= datalen;
}
cleanup(z);
return 1;
}
}
}
for (;;) {
if (roots(z->servers[z->level],d)) {
for (j = 0;j < QUERY_MAXNS;++j)
dns_domain_free(&z->ns[z->level][j]);
z->control[z->level] = d;
break;
}
if (!flagforwardonly && (z->level < 2))
if (dlen < 255) {
byte_copy(key,2,DNS_T_NS);
byte_copy(key + 2,dlen,d);
case_lowerb(key + 2,dlen);
cached = cache_get(key,dlen + 2,&cachedlen,&ttl);
if (cached && cachedlen) {
z->control[z->level] = d;
byte_zero(z->servers[z->level],64);
for (j = 0;j < QUERY_MAXNS;++j)
dns_domain_free(&z->ns[z->level][j]);
pos = 0;
j = 0;
while (pos = dns_packet_getname(cached,cachedlen,pos,&t1)) {
log_cachedns(d,t1);
if (j < QUERY_MAXNS)
if (!dns_domain_copy(&z->ns[z->level][j++],t1)) goto DIE;
}
break;
}
}
if (!*d) goto DIE;
j = 1 + (unsigned int) (unsigned char) *d;
dlen -= j;
d += j;
}
HAVENS:
for (j = 0;j < QUERY_MAXNS;++j)
if (z->ns[z->level][j]) {
if (z->level + 1 < QUERY_MAXLEVEL) {
if (!dns_domain_copy(&z->name[z->level + 1],z->ns[z->level][j])) goto DIE;
dns_domain_free(&z->ns[z->level][j]);
++z->level;
goto NEWNAME;
}
dns_domain_free(&z->ns[z->level][j]);
}
for (j = 0;j < 64;j += 4)
if (byte_diff(z->servers[z->level] + j,4,"\0\0\0\0"))
break;
if (j == 64) goto SERVFAIL;
dns_sortip(z->servers[z->level],64);
if (z->level) {
log_tx(z->name[z->level],DNS_T_A,z->control[z->level],z->servers[z->level],z->level);
if (dns_transmit_start(&z->dt,z->servers[z->level],flagforwardonly,z->name[z->level],DNS_T_A,z->localip) == -1) goto DIE;
}
else {
log_tx(z->name[0],z->type,z->control[0],z->servers[0],0);
if (dns_transmit_start(&z->dt,z->servers[0],flagforwardonly,z->name[0],z->type,z->localip) == -1) goto DIE;
}
return 0;
LOWERLEVEL:
dns_domain_free(&z->name[z->level]);
for (j = 0;j < QUERY_MAXNS;++j)
dns_domain_free(&z->ns[z->level][j]);
--z->level;
goto HAVENS;
HAVEPACKET:
if (++z->loop == 100) goto DIE;
buf = z->dt.packet;
len = z->dt.packetlen;
whichserver = z->dt.servers + 4 * z->dt.curserver;
control = z->control[z->level];
d = z->name[z->level];
dtype = z->level ? DNS_T_A : z->type;
pos = dns_packet_copy(buf,len,0,header,12); if (!pos) goto DIE;
pos = dns_packet_skipname(buf,len,pos); if (!pos) goto DIE;
pos += 4;
posanswers = pos;
uint16_unpack_big(header + 6,&numanswers);
uint16_unpack_big(header + 8,&numauthority);
uint16_unpack_big(header + 10,&numglue);
rcode = header[3] & 15;
if (rcode && (rcode != 3)) goto DIE; /* impossible; see irrelevant() */
flagout = 0;
flagcname = 0;
flagreferral = 0;
flagsoa = 0;
soattl = 0;
cnamettl = 0;
for (j = 0;j < numanswers;++j) {
pos = dns_packet_getname(buf,len,pos,&t1); if (!pos) goto DIE;
pos = dns_packet_copy(buf,len,pos,header,10); if (!pos) goto DIE;
if (dns_domain_equal(t1,d))
if (byte_equal(header + 2,2,DNS_C_IN)) { /* should always be true */
if (typematch(header,dtype))
flagout = 1;
else if (typematch(header,DNS_T_CNAME)) {
if (!dns_packet_getname(buf,len,pos,&cname)) goto DIE;
flagcname = 1;
cnamettl = ttlget(header + 4);
}
}
uint16_unpack_big(header + 8,&datalen);
pos += datalen;
}
posauthority = pos;
for (j = 0;j < numauthority;++j) {
pos = dns_packet_getname(buf,len,pos,&t1); if (!pos) goto DIE;
pos = dns_packet_copy(buf,len,pos,header,10); if (!pos) goto DIE;
if (typematch(header,DNS_T_SOA)) {
flagsoa = 1;
soattl = ttlget(header + 4);
if (soattl > 3600) soattl = 3600;
}
else if (typematch(header,DNS_T_NS)) {
flagreferral = 1;
if (!dns_domain_copy(&referral,t1)) goto DIE;
}
uint16_unpack_big(header + 8,&datalen);
pos += datalen;
}
posglue = pos;
if (!flagcname && !rcode && !flagout && flagreferral && !flagsoa)
if (dns_domain_equal(referral,control) || !dns_domain_suffix(referral,control)) {
log_lame(whichserver,control,referral);
byte_zero(whichserver,4);
goto HAVENS;
}
if (records) { alloc_free(records); records = 0; }
k = numanswers + numauthority + numglue;
records = (unsigned int *) alloc(k * sizeof(unsigned int));
if (!records) goto DIE;
pos = posanswers;
for (j = 0;j < k;++j) {
records[j] = pos;
pos = dns_packet_getname(buf,len,pos,&t1); if (!pos) goto DIE;
pos = dns_packet_copy(buf,len,pos,header,10); if (!pos) goto DIE;
uint16_unpack_big(header + 8,&datalen);
pos += datalen;
}
i = j = k;
while (j > 1) {
if (i > 1) { --i; pos = records[i - 1]; }
else { pos = records[j - 1]; records[j - 1] = records[i - 1]; --j; }
q = i;
while ((p = q * 2) < j) {
if (!smaller(buf,len,records[p],records[p - 1])) ++p;
records[q - 1] = records[p - 1]; q = p;
}
if (p == j) {
records[q - 1] = records[p - 1]; q = p;
}
while ((q > i) && smaller(buf,len,records[(p = q/2) - 1],pos)) {
records[q - 1] = records[p - 1]; q = p;
}
records[q - 1] = pos;
}
i = 0;
while (i < k) {
char type[2];
pos = dns_packet_getname(buf,len,records[i],&t1); if (!pos) goto DIE;
pos = dns_packet_copy(buf,len,pos,header,10); if (!pos) goto DIE;
ttl = ttlget(header + 4);
byte_copy(type,2,header);
if (byte_diff(header + 2,2,DNS_C_IN)) { ++i; continue; }
for (j = i + 1;j < k;++j) {
pos = dns_packet_getname(buf,len,records[j],&t2); if (!pos) goto DIE;
pos = dns_packet_copy(buf,len,pos,header,10); if (!pos) goto DIE;
if (!dns_domain_equal(t1,t2)) break;
if (byte_diff(header,2,type)) break;
if (byte_diff(header + 2,2,DNS_C_IN)) break;
}
if (!dns_domain_suffix(t1,control)) { i = j; continue; }
if (!roots_same(t1,control)) { i = j; continue; }
if (byte_equal(type,2,DNS_T_ANY))
;
else if (byte_equal(type,2,DNS_T_AXFR))
;
else if (byte_equal(type,2,DNS_T_SOA)) {
while (i < j) {
pos = dns_packet_skipname(buf,len,records[i]); if (!pos) goto DIE;
pos = dns_packet_getname(buf,len,pos + 10,&t2); if (!pos) goto DIE;
pos = dns_packet_getname(buf,len,pos,&t3); if (!pos) goto DIE;
pos = dns_packet_copy(buf,len,pos,misc,20); if (!pos) goto DIE;
if (records[i] < posauthority)
log_rrsoa(whichserver,t1,t2,t3,misc,ttl);
++i;
}
}
else if (byte_equal(type,2,DNS_T_CNAME)) {
pos = dns_packet_skipname(buf,len,records[j - 1]); if (!pos) goto DIE;
pos = dns_packet_getname(buf,len,pos + 10,&t2); if (!pos) goto DIE;
log_rrcname(whichserver,t1,t2,ttl);
cachegeneric(DNS_T_CNAME,t1,t2,dns_domain_length(t2),ttl);
}
else if (byte_equal(type,2,DNS_T_PTR)) {
save_start();
while (i < j) {
pos = dns_packet_skipname(buf,len,records[i]); if (!pos) goto DIE;
pos = dns_packet_getname(buf,len,pos + 10,&t2); if (!pos) goto DIE;
log_rrptr(whichserver,t1,t2,ttl);
save_data(t2,dns_domain_length(t2));
++i;
}
save_finish(DNS_T_PTR,t1,ttl);
}
else if (byte_equal(type,2,DNS_T_NS)) {
save_start();
while (i < j) {
pos = dns_packet_skipname(buf,len,records[i]); if (!pos) goto DIE;
pos = dns_packet_getname(buf,len,pos + 10,&t2); if (!pos) goto DIE;
log_rrns(whichserver,t1,t2,ttl);
save_data(t2,dns_domain_length(t2));
++i;
}
save_finish(DNS_T_NS,t1,ttl);
}
else if (byte_equal(type,2,DNS_T_MX)) {
save_start();
while (i < j) {
pos = dns_packet_skipname(buf,len,records[i]); if (!pos) goto DIE;
pos = dns_packet_copy(buf,len,pos + 10,misc,2); if (!pos) goto DIE;
pos = dns_packet_getname(buf,len,pos,&t2); if (!pos) goto DIE;
log_rrmx(whichserver,t1,t2,misc,ttl);
save_data(misc,2);
save_data(t2,dns_domain_length(t2));
++i;
}
save_finish(DNS_T_MX,t1,ttl);
}
else if (byte_equal(type,2,DNS_T_A)) {
save_start();
while (i < j) {
pos = dns_packet_skipname(buf,len,records[i]); if (!pos) goto DIE;
pos = dns_packet_copy(buf,len,pos,header,10); if (!pos) goto DIE;
if (byte_equal(header + 8,2,"\0\4")) {
pos = dns_packet_copy(buf,len,pos,header,4); if (!pos) goto DIE;
save_data(header,4);
log_rr(whichserver,t1,DNS_T_A,header,4,ttl);
}
++i;
}
save_finish(DNS_T_A,t1,ttl);
}
else {
save_start();
while (i < j) {
pos = dns_packet_skipname(buf,len,records[i]); if (!pos) goto DIE;
pos = dns_packet_copy(buf,len,pos,header,10); if (!pos) goto DIE;
uint16_unpack_big(header + 8,&datalen);
if (datalen > len - pos) goto DIE;
save_data(header + 8,2);
save_data(buf + pos,datalen);
log_rr(whichserver,t1,type,buf + pos,datalen,ttl);
++i;
}
save_finish(type,t1,ttl);
}
i = j;
}
alloc_free(records); records = 0;
if (flagcname) {
ttl = cnamettl;
CNAME:
if (!z->level) {
if (z->alias[QUERY_MAXALIAS - 1]) goto DIE;
for (j = QUERY_MAXALIAS - 1;j > 0;--j)
z->alias[j] = z->alias[j - 1];
for (j = QUERY_MAXALIAS - 1;j > 0;--j)
z->aliasttl[j] = z->aliasttl[j - 1];
z->alias[0] = z->name[0];
z->aliasttl[0] = ttl;
z->name[0] = 0;
}
if (!dns_domain_copy(&z->name[z->level],cname)) goto DIE;
goto NEWNAME;
}
if (rcode == 3) {
log_nxdomain(whichserver,d,soattl);
cachegeneric(DNS_T_ANY,d,"",0,soattl);
NXDOMAIN:
if (z->level) goto LOWERLEVEL;
if (!rqa(z)) goto DIE;
response_nxdomain();
cleanup(z);
return 1;
}
if (!flagout && flagsoa)
if (byte_diff(DNS_T_ANY,2,dtype))
if (byte_diff(DNS_T_AXFR,2,dtype))
if (byte_diff(DNS_T_CNAME,2,dtype)) {
save_start();
save_finish(dtype,d,soattl);
log_nodata(whichserver,d,dtype,soattl);
}
log_stats();
if (flagout || flagsoa || !flagreferral) {
if (z->level) {
pos = posanswers;
for (j = 0;j < numanswers;++j) {
pos = dns_packet_getname(buf,len,pos,&t1); if (!pos) goto DIE;
pos = dns_packet_copy(buf,len,pos,header,10); if (!pos) goto DIE;
uint16_unpack_big(header + 8,&datalen);
if (dns_domain_equal(t1,d))
if (typematch(header,DNS_T_A))
if (byte_equal(header + 2,2,DNS_C_IN)) /* should always be true */
if (datalen == 4)
for (k = 0;k < 64;k += 4)
if (byte_equal(z->servers[z->level - 1] + k,4,"\0\0\0\0")) {
if (!dns_packet_copy(buf,len,pos,z->servers[z->level - 1] + k,4)) goto DIE;
break;
}
pos += datalen;
}
goto LOWERLEVEL;
}
if (!rqa(z)) goto DIE;
pos = posanswers;
for (j = 0;j < numanswers;++j) {
pos = dns_packet_getname(buf,len,pos,&t1); if (!pos) goto DIE;
pos = dns_packet_copy(buf,len,pos,header,10); if (!pos) goto DIE;
ttl = ttlget(header + 4);
uint16_unpack_big(header + 8,&datalen);
if (dns_domain_equal(t1,d))
if (byte_equal(header + 2,2,DNS_C_IN)) /* should always be true */
if (typematch(header,dtype)) {
if (!response_rstart(t1,header,ttl)) goto DIE;
if (typematch(header,DNS_T_NS) || typematch(header,DNS_T_CNAME) || typematch(header,DNS_T_PTR)) {
if (!dns_packet_getname(buf,len,pos,&t2)) goto DIE;
if (!response_addname(t2)) goto DIE;
}
else if (typematch(header,DNS_T_MX)) {
pos2 = dns_packet_copy(buf,len,pos,misc,2); if (!pos2) goto DIE;
if (!response_addbytes(misc,2)) goto DIE;
if (!dns_packet_getname(buf,len,pos2,&t2)) goto DIE;
if (!response_addname(t2)) goto DIE;
}
else if (typematch(header,DNS_T_SOA)) {
pos2 = dns_packet_getname(buf,len,pos,&t2); if (!pos2) goto DIE;
if (!response_addname(t2)) goto DIE;
pos2 = dns_packet_getname(buf,len,pos2,&t3); if (!pos2) goto DIE;
if (!response_addname(t3)) goto DIE;
pos2 = dns_packet_copy(buf,len,pos2,misc,20); if (!pos2) goto DIE;
if (!response_addbytes(misc,20)) goto DIE;
}
else {
if (pos + datalen > len) goto DIE;
if (!response_addbytes(buf + pos,datalen)) goto DIE;
}
response_rfinish(RESPONSE_ANSWER);
}
pos += datalen;
}
cleanup(z);
return 1;
}
if (!dns_domain_suffix(d,referral)) goto DIE;
control = d + dns_domain_suffixpos(d,referral);
z->control[z->level] = control;
byte_zero(z->servers[z->level],64);
for (j = 0;j < QUERY_MAXNS;++j)
dns_domain_free(&z->ns[z->level][j]);
k = 0;
pos = posauthority;
for (j = 0;j < numauthority;++j) {
pos = dns_packet_getname(buf,len,pos,&t1); if (!pos) goto DIE;
pos = dns_packet_copy(buf,len,pos,header,10); if (!pos) goto DIE;
uint16_unpack_big(header + 8,&datalen);
if (dns_domain_equal(referral,t1)) /* should always be true */
if (typematch(header,DNS_T_NS)) /* should always be true */
if (byte_equal(header + 2,2,DNS_C_IN)) /* should always be true */
if (k < QUERY_MAXNS)
if (!dns_packet_getname(buf,len,pos,&z->ns[z->level][k++])) goto DIE;
pos += datalen;
}
goto HAVENS;
SERVFAIL:
if (z->level) goto LOWERLEVEL;
if (!rqa(z)) goto DIE;
response_servfail();
cleanup(z);
return 1;
DIE:
cleanup(z);
if (records) { alloc_free(records); records = 0; }
return -1;
}
int query_start(struct query *z,char *dn,char type[2],char class[2],char localip[4])
{
if (byte_equal(type,2,DNS_T_AXFR)) { errno = error_perm; return -1; }
cleanup(z);
z->level = 0;
z->loop = 0;
if (!dns_domain_copy(&z->name[0],dn)) return -1;
byte_copy(z->type,2,type);
byte_copy(z->class,2,class);
byte_copy(z->localip,4,localip);
return doit(z,0);
}
int query_get(struct query *z,iopause_fd *x,struct taia *stamp)
{
switch(dns_transmit_get(&z->dt,x,stamp)) {
case 1:
return doit(z,1);
case -1:
return doit(z,-1);
}
return 0;
}
void query_io(struct query *z,iopause_fd *x,struct taia *deadline)
{
dns_transmit_io(&z->dt,x,deadline);
}