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;
}
int
reply_info_encode(struct query_info* qinfo, struct reply_info* rep,
uint16_t id, uint16_t flags, ldns_buffer* buffer, uint32_t timenow,
struct regional* region, uint16_t udpsize, int dnssec)
{
uint16_t ancount=0, nscount=0, arcount=0;
struct compress_tree_node* tree = 0;
int r;
size_t rr_offset;
ldns_buffer_clear(buffer);
if(udpsize < ldns_buffer_limit(buffer))
ldns_buffer_set_limit(buffer, udpsize);
if(ldns_buffer_remaining(buffer) < LDNS_HEADER_SIZE)
return 0;
ldns_buffer_write(buffer, &id, sizeof(uint16_t));
ldns_buffer_write_u16(buffer, flags);
ldns_buffer_write_u16(buffer, rep->qdcount);
/* set an, ns, ar counts to zero in case of small packets */
ldns_buffer_write(buffer, "\000\000\000\000\000\000", 6);
/* insert query section */
if(rep->qdcount) {
if((r=insert_query(qinfo, &tree, buffer, region)) !=
RETVAL_OK) {
if(r == RETVAL_TRUNC) {
/* create truncated message */
ldns_buffer_write_u16_at(buffer, 4, 0);
LDNS_TC_SET(ldns_buffer_begin(buffer));
ldns_buffer_flip(buffer);
return 1;
}
return 0;
}
}
/* roundrobin offset. using query id for random number */
rr_offset = RRSET_ROUNDROBIN?id:0;
/* insert answer section */
if((r=insert_section(rep, rep->an_numrrsets, &ancount, buffer,
0, timenow, region, &tree, LDNS_SECTION_ANSWER, qinfo->qtype,
dnssec, rr_offset)) != RETVAL_OK) {
if(r == RETVAL_TRUNC) {
/* create truncated message */
ldns_buffer_write_u16_at(buffer, 6, ancount);
LDNS_TC_SET(ldns_buffer_begin(buffer));
ldns_buffer_flip(buffer);
return 1;
}
return 0;
}
ldns_buffer_write_u16_at(buffer, 6, ancount);
/* if response is positive answer, auth/add sections are not required */
if( ! (MINIMAL_RESPONSES && positive_answer(rep, qinfo->qtype)) ) {
/* insert auth section */
if((r=insert_section(rep, rep->ns_numrrsets, &nscount, buffer,
rep->an_numrrsets, timenow, region, &tree,
LDNS_SECTION_AUTHORITY, qinfo->qtype,
dnssec, rr_offset)) != RETVAL_OK) {
if(r == RETVAL_TRUNC) {
/* create truncated message */
ldns_buffer_write_u16_at(buffer, 8, nscount);
LDNS_TC_SET(ldns_buffer_begin(buffer));
ldns_buffer_flip(buffer);
return 1;
}
return 0;
}
ldns_buffer_write_u16_at(buffer, 8, nscount);
/* insert add section */
if((r=insert_section(rep, rep->ar_numrrsets, &arcount, buffer,
rep->an_numrrsets + rep->ns_numrrsets, timenow, region,
&tree, LDNS_SECTION_ADDITIONAL, qinfo->qtype,
dnssec, rr_offset)) != RETVAL_OK) {
if(r == RETVAL_TRUNC) {
/* no need to set TC bit, this is the additional */
ldns_buffer_write_u16_at(buffer, 10, arcount);
ldns_buffer_flip(buffer);
return 1;
}
return 0;
}
ldns_buffer_write_u16_at(buffer, 10, arcount);
} else {
ldns_buffer_write_u16_at(buffer, 8, nscount);
ldns_buffer_write_u16_at(buffer, 10, arcount);
}
ldns_buffer_flip(buffer);
return 1;
}
