void
attach_edns_record(ldns_buffer* pkt, struct edns_data* edns)
{
size_t len;
if(!edns || !edns->edns_present)
return;
/* inc additional count */
ldns_buffer_write_u16_at(pkt, 10,
ldns_buffer_read_u16_at(pkt, 10) + 1);
len = ldns_buffer_limit(pkt);
ldns_buffer_clear(pkt);
ldns_buffer_set_position(pkt, len);
/* write EDNS record */
ldns_buffer_write_u8(pkt, 0); /* '.' label */
ldns_buffer_write_u16(pkt, LDNS_RR_TYPE_OPT); /* type */
ldns_buffer_write_u16(pkt, edns->udp_size); /* class */
ldns_buffer_write_u8(pkt, edns->ext_rcode); /* ttl */
ldns_buffer_write_u8(pkt, edns->edns_version);
ldns_buffer_write_u16(pkt, edns->bits);
ldns_buffer_write_u16(pkt, 0); /* rdatalen */
ldns_buffer_flip(pkt);
}
void server_stats_insquery(struct server_stats* stats, struct comm_point* c,
uint16_t qtype, uint16_t qclass, struct edns_data* edns,
struct comm_reply* repinfo)
{
uint16_t flags = ldns_buffer_read_u16_at(c->buffer, 2);
if(qtype < STATS_QTYPE_NUM)
stats->qtype[qtype]++;
else stats->qtype_big++;
if(qclass < STATS_QCLASS_NUM)
stats->qclass[qclass]++;
else stats->qclass_big++;
stats->qopcode[ LDNS_OPCODE_WIRE(ldns_buffer_begin(c->buffer)) ]++;
if(c->type != comm_udp)
stats->qtcp++;
if(repinfo && addr_is_ip6(&repinfo->addr, repinfo->addrlen))
stats->qipv6++;
if( (flags&BIT_QR) )
stats->qbit_QR++;
if( (flags&BIT_AA) )
stats->qbit_AA++;
if( (flags&BIT_TC) )
stats->qbit_TC++;
if( (flags&BIT_RD) )
stats->qbit_RD++;
if( (flags&BIT_RA) )
stats->qbit_RA++;
if( (flags&BIT_Z) )
stats->qbit_Z++;
if( (flags&BIT_AD) )
stats->qbit_AD++;
if( (flags&BIT_CD) )
stats->qbit_CD++;
if(edns->edns_present) {
stats->qEDNS++;
if( (edns->bits & EDNS_DO) )
stats->qEDNS_DO++;
}
}
/**
* Send reply to mesh reply entry
* @param m: mesh state to send it for.
* @param rcode: if not 0, error code.
* @param rep: reply to send (or NULL if rcode is set).
* @param r: reply entry
* @param prev: previous reply, already has its answer encoded in buffer.
*/
static void
mesh_send_reply(struct mesh_state* m, int rcode, struct reply_info* rep,
struct mesh_reply* r, struct mesh_reply* prev)
{
struct timeval end_time;
struct timeval duration;
int secure;
/* examine security status */
if(m->s.env->need_to_validate && (!(r->qflags&BIT_CD) ||
m->s.env->cfg->ignore_cd) && rep &&
rep->security <= sec_status_bogus) {
rcode = LDNS_RCODE_SERVFAIL;
if(m->s.env->cfg->stat_extended)
m->s.env->mesh->ans_bogus++;
}
if(rep && rep->security == sec_status_secure)
secure = 1;
else secure = 0;
if(!rep && rcode == LDNS_RCODE_NOERROR)
rcode = LDNS_RCODE_SERVFAIL;
/* send the reply */
if(prev && prev->qflags == r->qflags &&
prev->edns.edns_present == r->edns.edns_present &&
prev->edns.bits == r->edns.bits &&
prev->edns.udp_size == r->edns.udp_size) {
/* if the previous reply is identical to this one, fix ID */
if(prev->query_reply.c->buffer != r->query_reply.c->buffer)
ldns_buffer_copy(r->query_reply.c->buffer,
prev->query_reply.c->buffer);
ldns_buffer_write_at(r->query_reply.c->buffer, 0,
&r->qid, sizeof(uint16_t));
ldns_buffer_write_at(r->query_reply.c->buffer, 12,
r->qname, m->s.qinfo.qname_len);
comm_point_send_reply(&r->query_reply);
} else if(rcode) {
m->s.qinfo.qname = r->qname;
error_encode(r->query_reply.c->buffer, rcode, &m->s.qinfo,
r->qid, r->qflags, &r->edns);
comm_point_send_reply(&r->query_reply);
} else {
size_t udp_size = r->edns.udp_size;
r->edns.edns_version = EDNS_ADVERTISED_VERSION;
r->edns.udp_size = EDNS_ADVERTISED_SIZE;
r->edns.ext_rcode = 0;
r->edns.bits &= EDNS_DO;
m->s.qinfo.qname = r->qname;
if(!reply_info_answer_encode(&m->s.qinfo, rep, r->qid,
r->qflags, r->query_reply.c->buffer, 0, 1,
m->s.env->scratch, udp_size, &r->edns,
(int)(r->edns.bits & EDNS_DO), secure))
{
error_encode(r->query_reply.c->buffer,
LDNS_RCODE_SERVFAIL, &m->s.qinfo, r->qid,
r->qflags, &r->edns);
}
comm_point_send_reply(&r->query_reply);
}
/* account */
m->s.env->mesh->num_reply_addrs--;
end_time = *m->s.env->now_tv;
timeval_subtract(&duration, &end_time, &r->start_time);
verbose(VERB_ALGO, "query took %d.%6.6d sec",
(int)duration.tv_sec, (int)duration.tv_usec);
m->s.env->mesh->replies_sent++;
timeval_add(&m->s.env->mesh->replies_sum_wait, &duration);
timehist_insert(m->s.env->mesh->histogram, &duration);
if(m->s.env->cfg->stat_extended) {
uint16_t rc = FLAGS_GET_RCODE(ldns_buffer_read_u16_at(r->
query_reply.c->buffer, 2));
if(secure) m->s.env->mesh->ans_secure++;
m->s.env->mesh->ans_rcode[ rc ] ++;
if(rc == 0 && LDNS_ANCOUNT(ldns_buffer_begin(r->
query_reply.c->buffer)) == 0)
m->s.env->mesh->ans_nodata++;
}
}
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;
}
