int
worker_handle_request(struct comm_point* c, void* arg, int error,
struct comm_reply* repinfo)
{
struct worker* worker = (struct worker*)arg;
int ret;
hashvalue_t h;
struct lruhash_entry* e;
struct query_info qinfo;
struct edns_data edns;
enum acl_access acl;
int rc = 0;
if(error != NETEVENT_NOERROR) {
/* some bad tcp query DNS formats give these error calls */
verbose(VERB_ALGO, "handle request called with err=%d", error);
return 0;
}
#ifdef USE_DNSTAP
if(worker->dtenv.log_client_query_messages)
dt_msg_send_client_query(&worker->dtenv, &repinfo->addr, c->type,
c->buffer);
#endif
acl = acl_list_lookup(worker->daemon->acl, &repinfo->addr,
repinfo->addrlen);
if((ret=deny_refuse_all(c, acl, worker, repinfo)) != -1)
{
if(ret == 1)
goto send_reply;
return ret;
}
if((ret=worker_check_request(c->buffer, worker)) != 0) {
verbose(VERB_ALGO, "worker check request: bad query.");
log_addr(VERB_CLIENT,"from",&repinfo->addr, repinfo->addrlen);
if(ret != -1) {
LDNS_QR_SET(sldns_buffer_begin(c->buffer));
LDNS_RCODE_SET(sldns_buffer_begin(c->buffer), ret);
return 1;
}
comm_point_drop_reply(repinfo);
return 0;
}
worker->stats.num_queries++;
/* see if query is in the cache */
if(!query_info_parse(&qinfo, c->buffer)) {
verbose(VERB_ALGO, "worker parse request: formerror.");
log_addr(VERB_CLIENT,"from",&repinfo->addr, repinfo->addrlen);
if(worker_err_ratelimit(worker, LDNS_RCODE_FORMERR) == -1) {
comm_point_drop_reply(repinfo);
return 0;
}
sldns_buffer_rewind(c->buffer);
LDNS_QR_SET(sldns_buffer_begin(c->buffer));
LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
LDNS_RCODE_FORMERR);
server_stats_insrcode(&worker->stats, c->buffer);
goto send_reply;
}
if(worker->env.cfg->log_queries) {
char ip[128];
addr_to_str(&repinfo->addr, repinfo->addrlen, ip, sizeof(ip));
log_nametypeclass(0, ip, qinfo.qname, qinfo.qtype, qinfo.qclass);
}
if(qinfo.qtype == LDNS_RR_TYPE_AXFR ||
qinfo.qtype == LDNS_RR_TYPE_IXFR) {
verbose(VERB_ALGO, "worker request: refused zone transfer.");
log_addr(VERB_CLIENT,"from",&repinfo->addr, repinfo->addrlen);
sldns_buffer_rewind(c->buffer);
LDNS_QR_SET(sldns_buffer_begin(c->buffer));
LDNS_RCODE_SET(sldns_buffer_begin(c->buffer),
LDNS_RCODE_REFUSED);
if(worker->stats.extended) {
worker->stats.qtype[qinfo.qtype]++;
server_stats_insrcode(&worker->stats, c->buffer);
}
goto send_reply;
}
if((ret=parse_edns_from_pkt(c->buffer, &edns, worker->scratchpad)) != 0) {
struct edns_data reply_edns;
verbose(VERB_ALGO, "worker parse edns: formerror.");
log_addr(VERB_CLIENT,"from",&repinfo->addr, repinfo->addrlen);
memset(&reply_edns, 0, sizeof(reply_edns));
reply_edns.edns_present = 1;
reply_edns.udp_size = EDNS_ADVERTISED_SIZE;
LDNS_RCODE_SET(sldns_buffer_begin(c->buffer), ret);
error_encode(c->buffer, ret, &qinfo,
*(uint16_t*)(void *)sldns_buffer_begin(c->buffer),
sldns_buffer_read_u16_at(c->buffer, 2), &reply_edns);
regional_free_all(worker->scratchpad);
server_stats_insrcode(&worker->stats, c->buffer);
goto send_reply;
}
if(edns.edns_present && edns.edns_version != 0) {
edns.ext_rcode = (uint8_t)(EDNS_RCODE_BADVERS>>4);
edns.edns_version = EDNS_ADVERTISED_VERSION;
edns.udp_size = EDNS_ADVERTISED_SIZE;
edns.bits &= EDNS_DO;
edns.opt_list = NULL;
verbose(VERB_ALGO, "query with bad edns version.");
log_addr(VERB_CLIENT,"from",&repinfo->addr, repinfo->addrlen);
error_encode(c->buffer, EDNS_RCODE_BADVERS&0xf, &qinfo,
*(uint16_t*)(void *)sldns_buffer_begin(c->buffer),
sldns_buffer_read_u16_at(c->buffer, 2), NULL);
attach_edns_record(c->buffer, &edns);
regional_free_all(worker->scratchpad);
goto send_reply;
}
/** answer nonrecursive query from the cache */
static int
answer_norec_from_cache(struct worker* worker, struct query_info* qinfo,
uint16_t id, uint16_t flags, struct comm_reply* repinfo,
struct edns_data* edns)
{
/* for a nonrecursive query return either:
* o an error (servfail; we try to avoid this)
* o a delegation (closest we have; this routine tries that)
* o the answer (checked by answer_from_cache)
*
* So, grab a delegation from the rrset cache.
* Then check if it needs validation, if so, this routine fails,
* so that iterator can prime and validator can verify rrsets.
*/
uint16_t udpsize = edns->udp_size;
int secure = 0;
time_t timenow = *worker->env.now;
int must_validate = (!(flags&BIT_CD) || worker->env.cfg->ignore_cd)
&& worker->env.need_to_validate;
struct dns_msg *msg = NULL;
struct delegpt *dp;
dp = dns_cache_find_delegation(&worker->env, qinfo->qname,
qinfo->qname_len, qinfo->qtype, qinfo->qclass,
worker->scratchpad, &msg, timenow);
if(!dp) { /* no delegation, need to reprime */
return 0;
}
if(must_validate) {
switch(check_delegation_secure(msg->rep)) {
case sec_status_unchecked:
/* some rrsets have not been verified yet, go and
* let validator do that */
return 0;
case sec_status_bogus:
/* some rrsets are bogus, reply servfail */
edns->edns_version = EDNS_ADVERTISED_VERSION;
edns->udp_size = EDNS_ADVERTISED_SIZE;
edns->ext_rcode = 0;
edns->bits &= EDNS_DO;
if(!edns_opt_inplace_reply(edns, worker->scratchpad))
return 0;
error_encode(repinfo->c->buffer, LDNS_RCODE_SERVFAIL,
&msg->qinfo, id, flags, edns);
if(worker->stats.extended) {
worker->stats.ans_bogus++;
worker->stats.ans_rcode[LDNS_RCODE_SERVFAIL]++;
}
return 1;
case sec_status_secure:
/* all rrsets are secure */
/* remove non-secure rrsets from the add. section*/
if(worker->env.cfg->val_clean_additional)
deleg_remove_nonsecure_additional(msg->rep);
secure = 1;
break;
case sec_status_indeterminate:
case sec_status_insecure:
default:
/* not secure */
secure = 0;
break;
}
}
/* return this delegation from the cache */
edns->edns_version = EDNS_ADVERTISED_VERSION;
edns->udp_size = EDNS_ADVERTISED_SIZE;
edns->ext_rcode = 0;
edns->bits &= EDNS_DO;
if(!edns_opt_inplace_reply(edns, worker->scratchpad))
return 0;
msg->rep->flags |= BIT_QR|BIT_RA;
if(!reply_info_answer_encode(&msg->qinfo, msg->rep, id, flags,
repinfo->c->buffer, 0, 1, worker->scratchpad,
udpsize, edns, (int)(edns->bits & EDNS_DO), secure)) {
error_encode(repinfo->c->buffer, LDNS_RCODE_SERVFAIL,
&msg->qinfo, id, flags, edns);
}
if(worker->stats.extended) {
if(secure) worker->stats.ans_secure++;
server_stats_insrcode(&worker->stats, repinfo->c->buffer);
}
return 1;
}
/** answer query from the cache */
static int
answer_from_cache(struct worker* worker, struct query_info* qinfo,
struct reply_info* rep, uint16_t id, uint16_t flags,
struct comm_reply* repinfo, struct edns_data* edns)
{
time_t timenow = *worker->env.now;
uint16_t udpsize = edns->udp_size;
int secure;
int must_validate = (!(flags&BIT_CD) || worker->env.cfg->ignore_cd)
&& worker->env.need_to_validate;
/* see if it is possible */
if(rep->ttl < timenow) {
/* the rrsets may have been updated in the meantime.
* we will refetch the message format from the
* authoritative server
*/
return 0;
}
if(!rrset_array_lock(rep->ref, rep->rrset_count, timenow))
return 0;
/* locked and ids and ttls are OK. */
/* check CNAME chain (if any) */
if(rep->an_numrrsets > 0 && (rep->rrsets[0]->rk.type ==
htons(LDNS_RR_TYPE_CNAME) || rep->rrsets[0]->rk.type ==
htons(LDNS_RR_TYPE_DNAME))) {
if(!reply_check_cname_chain(qinfo, rep)) {
/* cname chain invalid, redo iterator steps */
verbose(VERB_ALGO, "Cache reply: cname chain broken");
bail_out:
rrset_array_unlock_touch(worker->env.rrset_cache,
worker->scratchpad, rep->ref, rep->rrset_count);
return 0;
}
}
/* check security status of the cached answer */
if( rep->security == sec_status_bogus && must_validate) {
/* BAD cached */
edns->edns_version = EDNS_ADVERTISED_VERSION;
edns->udp_size = EDNS_ADVERTISED_SIZE;
edns->ext_rcode = 0;
edns->bits &= EDNS_DO;
if(!edns_opt_inplace_reply(edns, worker->scratchpad))
return 0;
error_encode(repinfo->c->buffer, LDNS_RCODE_SERVFAIL,
qinfo, id, flags, edns);
rrset_array_unlock_touch(worker->env.rrset_cache,
worker->scratchpad, rep->ref, rep->rrset_count);
if(worker->stats.extended) {
worker->stats.ans_bogus ++;
worker->stats.ans_rcode[LDNS_RCODE_SERVFAIL] ++;
}
return 1;
} else if( rep->security == sec_status_unchecked && must_validate) {
verbose(VERB_ALGO, "Cache reply: unchecked entry needs "
"validation");
goto bail_out; /* need to validate cache entry first */
} else if(rep->security == sec_status_secure) {
if(reply_all_rrsets_secure(rep))
secure = 1;
else {
if(must_validate) {
verbose(VERB_ALGO, "Cache reply: secure entry"
" changed status");
goto bail_out; /* rrset changed, re-verify */
}
secure = 0;
}
} else secure = 0;
edns->edns_version = EDNS_ADVERTISED_VERSION;
edns->udp_size = EDNS_ADVERTISED_SIZE;
edns->ext_rcode = 0;
edns->bits &= EDNS_DO;
if(!edns_opt_inplace_reply(edns, worker->scratchpad))
return 0;
if(!reply_info_answer_encode(qinfo, rep, id, flags,
repinfo->c->buffer, timenow, 1, worker->scratchpad,
udpsize, edns, (int)(edns->bits & EDNS_DO), secure)) {
error_encode(repinfo->c->buffer, LDNS_RCODE_SERVFAIL,
qinfo, id, flags, edns);
}
/* cannot send the reply right now, because blocking network syscall
* is bad while holding locks. */
rrset_array_unlock_touch(worker->env.rrset_cache, worker->scratchpad,
rep->ref, rep->rrset_count);
if(worker->stats.extended) {
if(secure) worker->stats.ans_secure++;
server_stats_insrcode(&worker->stats, repinfo->c->buffer);
}
/* go and return this buffer to the client */
return 1;
}
int
worker_handle_request(struct comm_point* c, void* arg, int error,
struct comm_reply* repinfo)
{
struct worker* worker = (struct worker*)arg;
int ret;
hashvalue_t h;
struct lruhash_entry* e;
struct query_info qinfo;
struct edns_data edns;
enum acl_access acl;
if(error != NETEVENT_NOERROR) {
/* some bad tcp query DNS formats give these error calls */
verbose(VERB_ALGO, "handle request called with err=%d", error);
return 0;
}
acl = acl_list_lookup(worker->daemon->acl, &repinfo->addr,
repinfo->addrlen);
if(acl == acl_deny) {
comm_point_drop_reply(repinfo);
if(worker->stats.extended)
worker->stats.unwanted_queries++;
return 0;
} else if(acl == acl_refuse) {
log_addr(VERB_ALGO, "refused query from",
&repinfo->addr, repinfo->addrlen);
log_buf(VERB_ALGO, "refuse", c->buffer);
if(worker->stats.extended)
worker->stats.unwanted_queries++;
if(worker_check_request(c->buffer, worker) == -1) {
comm_point_drop_reply(repinfo);
return 0; /* discard this */
}
ldns_buffer_set_limit(c->buffer, LDNS_HEADER_SIZE);
ldns_buffer_write_at(c->buffer, 4,
(uint8_t*)"\0\0\0\0\0\0\0\0", 8);
LDNS_QR_SET(ldns_buffer_begin(c->buffer));
LDNS_RCODE_SET(ldns_buffer_begin(c->buffer),
LDNS_RCODE_REFUSED);
return 1;
}
if((ret=worker_check_request(c->buffer, worker)) != 0) {
verbose(VERB_ALGO, "worker check request: bad query.");
log_addr(VERB_CLIENT,"from",&repinfo->addr, repinfo->addrlen);
if(ret != -1) {
LDNS_QR_SET(ldns_buffer_begin(c->buffer));
LDNS_RCODE_SET(ldns_buffer_begin(c->buffer), ret);
return 1;
}
comm_point_drop_reply(repinfo);
return 0;
}
worker->stats.num_queries++;
/* see if query is in the cache */
if(!query_info_parse(&qinfo, c->buffer)) {
verbose(VERB_ALGO, "worker parse request: formerror.");
log_addr(VERB_CLIENT,"from",&repinfo->addr, repinfo->addrlen);
ldns_buffer_rewind(c->buffer);
LDNS_QR_SET(ldns_buffer_begin(c->buffer));
LDNS_RCODE_SET(ldns_buffer_begin(c->buffer),
LDNS_RCODE_FORMERR);
server_stats_insrcode(&worker->stats, c->buffer);
return 1;
}
if(worker->env.cfg->log_queries) {
char ip[128];
addr_to_str(&repinfo->addr, repinfo->addrlen, ip, sizeof(ip));
log_nametypeclass(0, ip, qinfo.qname, qinfo.qtype, qinfo.qclass);
}
if(qinfo.qtype == LDNS_RR_TYPE_AXFR ||
qinfo.qtype == LDNS_RR_TYPE_IXFR) {
verbose(VERB_ALGO, "worker request: refused zone transfer.");
log_addr(VERB_CLIENT,"from",&repinfo->addr, repinfo->addrlen);
ldns_buffer_rewind(c->buffer);
LDNS_QR_SET(ldns_buffer_begin(c->buffer));
LDNS_RCODE_SET(ldns_buffer_begin(c->buffer),
LDNS_RCODE_REFUSED);
if(worker->stats.extended) {
worker->stats.qtype[qinfo.qtype]++;
server_stats_insrcode(&worker->stats, c->buffer);
}
return 1;
}
if((ret=parse_edns_from_pkt(c->buffer, &edns)) != 0) {
verbose(VERB_ALGO, "worker parse edns: formerror.");
log_addr(VERB_CLIENT,"from",&repinfo->addr, repinfo->addrlen);
ldns_buffer_rewind(c->buffer);
LDNS_QR_SET(ldns_buffer_begin(c->buffer));
LDNS_RCODE_SET(ldns_buffer_begin(c->buffer), ret);
server_stats_insrcode(&worker->stats, c->buffer);
return 1;
}
if(edns.edns_present && edns.edns_version != 0) {
edns.ext_rcode = (uint8_t)(EDNS_RCODE_BADVERS>>4);
edns.edns_version = EDNS_ADVERTISED_VERSION;
edns.udp_size = EDNS_ADVERTISED_SIZE;
edns.bits &= EDNS_DO;
verbose(VERB_ALGO, "query with bad edns version.");
log_addr(VERB_CLIENT,"from",&repinfo->addr, repinfo->addrlen);
error_encode(c->buffer, EDNS_RCODE_BADVERS&0xf, &qinfo,
*(uint16_t*)ldns_buffer_begin(c->buffer),
ldns_buffer_read_u16_at(c->buffer, 2), NULL);
attach_edns_record(c->buffer, &edns);
return 1;
}