/** check request sanity.
* @param pkt: the wire packet to examine for sanity.
* @param worker: parameters for checking.
* @return error code, 0 OK, or -1 discard.
*/
static int
worker_check_request(sldns_buffer* pkt, struct worker* worker)
{
if(sldns_buffer_limit(pkt) < LDNS_HEADER_SIZE) {
verbose(VERB_QUERY, "request too short, discarded");
return -1;
}
if(sldns_buffer_limit(pkt) > NORMAL_UDP_SIZE &&
worker->daemon->cfg->harden_large_queries) {
verbose(VERB_QUERY, "request too large, discarded");
return -1;
}
if(LDNS_QR_WIRE(sldns_buffer_begin(pkt))) {
verbose(VERB_QUERY, "request has QR bit on, discarded");
return -1;
}
if(LDNS_TC_WIRE(sldns_buffer_begin(pkt))) {
LDNS_TC_CLR(sldns_buffer_begin(pkt));
verbose(VERB_QUERY, "request bad, has TC bit on");
return worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
}
if(LDNS_OPCODE_WIRE(sldns_buffer_begin(pkt)) != LDNS_PACKET_QUERY) {
verbose(VERB_QUERY, "request unknown opcode %d",
LDNS_OPCODE_WIRE(sldns_buffer_begin(pkt)));
return worker_err_ratelimit(worker, LDNS_RCODE_NOTIMPL);
}
if(LDNS_QDCOUNT(sldns_buffer_begin(pkt)) != 1) {
verbose(VERB_QUERY, "request wrong nr qd=%d",
LDNS_QDCOUNT(sldns_buffer_begin(pkt)));
return worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
}
if(LDNS_ANCOUNT(sldns_buffer_begin(pkt)) != 0) {
verbose(VERB_QUERY, "request wrong nr an=%d",
LDNS_ANCOUNT(sldns_buffer_begin(pkt)));
return worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
}
if(LDNS_NSCOUNT(sldns_buffer_begin(pkt)) != 0) {
verbose(VERB_QUERY, "request wrong nr ns=%d",
LDNS_NSCOUNT(sldns_buffer_begin(pkt)));
return worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
}
if(LDNS_ARCOUNT(sldns_buffer_begin(pkt)) > 1) {
verbose(VERB_QUERY, "request wrong nr ar=%d",
LDNS_ARCOUNT(sldns_buffer_begin(pkt)));
return worker_err_ratelimit(worker, LDNS_RCODE_FORMERR);
}
return 0;
}
int
worker_handle_service_reply(struct comm_point* c, void* arg, int error,
struct comm_reply* reply_info)
{
struct outbound_entry* e = (struct outbound_entry*)arg;
struct worker* worker = e->qstate->env->worker;
struct serviced_query *sq = e->qsent;
verbose(VERB_ALGO, "worker svcd callback for qstate %p", e->qstate);
if(error != 0) {
mesh_report_reply(worker->env.mesh, e, reply_info, error);
worker_mem_report(worker, sq);
return 0;
}
/* sanity check. */
if(!LDNS_QR_WIRE(sldns_buffer_begin(c->buffer))
|| LDNS_OPCODE_WIRE(sldns_buffer_begin(c->buffer)) !=
LDNS_PACKET_QUERY
|| LDNS_QDCOUNT(sldns_buffer_begin(c->buffer)) > 1) {
/* error becomes timeout for the module as if this reply
* never arrived. */
verbose(VERB_ALGO, "worker: bad reply handled as timeout");
mesh_report_reply(worker->env.mesh, e, reply_info,
NETEVENT_TIMEOUT);
worker_mem_report(worker, sq);
return 0;
}
mesh_report_reply(worker->env.mesh, e, reply_info, NETEVENT_NOERROR);
worker_mem_report(worker, sq);
return 0;
}
int
worker_handle_reply(struct comm_point* c, void* arg, int error,
struct comm_reply* reply_info)
{
struct module_qstate* q = (struct module_qstate*)arg;
struct worker* worker = q->env->worker;
struct outbound_entry e;
e.qstate = q;
e.qsent = NULL;
if(error != 0) {
mesh_report_reply(worker->env.mesh, &e, reply_info, error);
worker_mem_report(worker, NULL);
return 0;
}
/* sanity check. */
if(!LDNS_QR_WIRE(sldns_buffer_begin(c->buffer))
|| LDNS_OPCODE_WIRE(sldns_buffer_begin(c->buffer)) !=
LDNS_PACKET_QUERY
|| LDNS_QDCOUNT(sldns_buffer_begin(c->buffer)) > 1) {
/* error becomes timeout for the module as if this reply
* never arrived. */
mesh_report_reply(worker->env.mesh, &e, reply_info,
NETEVENT_TIMEOUT);
worker_mem_report(worker, NULL);
return 0;
}
mesh_report_reply(worker->env.mesh, &e, reply_info, NETEVENT_NOERROR);
worker_mem_report(worker, NULL);
return 0;
}
int
libworker_handle_service_reply(struct comm_point* c, void* arg, int error,
struct comm_reply* reply_info)
{
struct outbound_entry* e = (struct outbound_entry*)arg;
struct libworker* lw = (struct libworker*)e->qstate->env->worker;
if(error != 0) {
mesh_report_reply(lw->env->mesh, e, reply_info, error);
return 0;
}
/* sanity check. */
if(!LDNS_QR_WIRE(sldns_buffer_begin(c->buffer))
|| LDNS_OPCODE_WIRE(sldns_buffer_begin(c->buffer)) !=
LDNS_PACKET_QUERY
|| LDNS_QDCOUNT(sldns_buffer_begin(c->buffer)) > 1) {
/* error becomes timeout for the module as if this reply
* never arrived. */
mesh_report_reply(lw->env->mesh, e, reply_info,
NETEVENT_TIMEOUT);
return 0;
}
mesh_report_reply(lw->env->mesh, e, reply_info, NETEVENT_NOERROR);
return 0;
}
int
query_info_parse(struct query_info* m, sldns_buffer* query)
{
uint8_t* q = sldns_buffer_begin(query);
/* minimum size: header + \0 + qtype + qclass */
if(sldns_buffer_limit(query) < LDNS_HEADER_SIZE + 5)
return 0;
if(LDNS_OPCODE_WIRE(q) != LDNS_PACKET_QUERY ||
LDNS_QDCOUNT(q) != 1 || sldns_buffer_position(query) != 0)
return 0;
sldns_buffer_skip(query, LDNS_HEADER_SIZE);
m->qname = sldns_buffer_current(query);
if((m->qname_len = query_dname_len(query)) == 0)
return 0; /* parse error */
if(sldns_buffer_remaining(query) < 4)
return 0; /* need qtype, qclass */
m->qtype = sldns_buffer_read_u16(query);
m->qclass = sldns_buffer_read_u16(query);
return 1;
}
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++;
}
}
