static void reset_probe (struct probe_trans *trans)
{
struct probe_ns *pns;
struct server *server;
isc_result_t result;
REQUIRE (trans->resid == NULL);
REQUIRE (trans->reqid == NULL);
update_stat (trans);
dns_message_reset (trans->qmessage, DNS_MESSAGE_INTENTRENDER);
dns_message_reset (trans->rmessage, DNS_MESSAGE_INTENTPARSE);
trans->inuse = ISC_FALSE;
if (trans->domain != NULL)
isc_mem_free (mctx, trans->domain);
trans->domain = NULL;
if (trans->qname != NULL)
dns_fixedname_invalidate (&trans->fixedname);
trans->qname = NULL;
trans->qlabel = qlabels;
trans->qname_found = ISC_FALSE;
trans->current_ns = NULL;
while ((pns = ISC_LIST_HEAD (trans->nslist)) != NULL)
{
ISC_LIST_UNLINK (trans->nslist, pns, link);
while ((server = ISC_LIST_HEAD (pns->servers)) != NULL)
{
ISC_LIST_UNLINK (pns->servers, server, link);
isc_mem_put (mctx, server, sizeof (*server));
}
isc_mem_put (mctx, pns, sizeof (*pns));
}
outstanding_probes--;
result = probe_domain (trans);
if (result == ISC_R_NOMORE && outstanding_probes == 0)
isc_app_ctxshutdown (actx);
}
static isc_result_t
probe_name(struct probe_trans *trans, dns_rdatatype_t type) {
isc_result_t result;
struct probe_ns *pns;
struct server *server;
REQUIRE(trans->reqid == NULL);
REQUIRE(type == dns_rdatatype_a || type == dns_rdatatype_aaaa);
for (pns = trans->current_ns; pns != NULL;
pns = ISC_LIST_NEXT(pns, link)) {
for (server = ISC_LIST_HEAD(pns->servers); server != NULL;
server = ISC_LIST_NEXT(server, link)) {
if ((type == dns_rdatatype_a &&
server->result_a == none) ||
(type == dns_rdatatype_aaaa &&
server->result_aaaa == none)) {
pns->current_server = server;
goto found;
}
}
}
found:
trans->current_ns = pns;
if (pns == NULL)
return (ISC_R_NOMORE);
INSIST(pns->current_server != NULL);
dns_message_reset(trans->qmessage, DNS_MESSAGE_INTENTRENDER);
result = make_querymessage(trans->qmessage, trans->qname, type);
if (result != ISC_R_SUCCESS)
return (result);
result = dns_client_startrequest(client, trans->qmessage,
trans->rmessage,
&pns->current_server->address,
0, DNS_MESSAGEPARSE_BESTEFFORT,
NULL, 120, 0, 4,
probe_task, request_done, trans,
&trans->reqid);
return (result);
}
static void
request_done(isc_task_t *task, isc_event_t *event) {
struct probe_trans *trans = event->ev_arg;
dns_clientreqevent_t *rev = (dns_clientreqevent_t *)event;
dns_message_t *rmessage;
struct probe_ns *pns;
struct server *server;
isc_result_t result;
query_result_t *resultp;
dns_name_t *name;
dns_rdataset_t *rdataset;
dns_rdatatype_t type;
REQUIRE(task == probe_task);
REQUIRE(trans != NULL && trans->inuse == ISC_TRUE);
rmessage = rev->rmessage;
REQUIRE(rmessage == trans->rmessage);
INSIST(outstanding_probes > 0);
server = trans->current_ns->current_server;
INSIST(server != NULL);
if (server->result_a == none) {
type = dns_rdatatype_a;
resultp = &server->result_a;
} else {
resultp = &server->result_aaaa;
type = dns_rdatatype_aaaa;
}
if (rev->result == ISC_R_SUCCESS) {
if ((rmessage->flags & DNS_MESSAGEFLAG_AA) == 0)
*resultp = lame;
else if (rmessage->rcode == dns_rcode_nxdomain)
*resultp = nxdomain;
else if (rmessage->rcode != dns_rcode_noerror)
*resultp = othererr;
else if (rmessage->counts[DNS_SECTION_ANSWER] == 0) {
/* no error but empty answer */
*resultp = notype;
} else {
result = dns_message_firstname(rmessage,
DNS_SECTION_ANSWER);
while (result == ISC_R_SUCCESS) {
name = NULL;
dns_message_currentname(rmessage,
DNS_SECTION_ANSWER,
&name);
for (rdataset = ISC_LIST_HEAD(name->list);
rdataset != NULL;
rdataset = ISC_LIST_NEXT(rdataset,
link)) {
(void)print_rdataset(rdataset, name);
if (rdataset->type ==
dns_rdatatype_cname ||
rdataset->type ==
dns_rdatatype_dname) {
/* Should chase the chain? */
*resultp = exist;
goto found;
} else if (rdataset->type == type) {
*resultp = exist;
goto found;
}
}
result = dns_message_nextname(rmessage,
DNS_SECTION_ANSWER);
}
/*
* Something unexpected happened: the response
* contained a non-empty authoritative answer, but we
* could not find an expected result.
*/
*resultp = unexpected;
}
} else if (rev->result == DNS_R_RECOVERABLE ||
rev->result == DNS_R_BADLABELTYPE) {
/* Broken response. Try identifying known cases. */
*resultp = brokenanswer;
if (rmessage->counts[DNS_SECTION_ANSWER] > 0) {
result = dns_message_firstname(rmessage,
DNS_SECTION_ANSWER);
while (result == ISC_R_SUCCESS) {
/*
* Check to see if the response has multiple
* CNAME RRs. Update the result code if so.
*/
name = NULL;
dns_message_currentname(rmessage,
DNS_SECTION_ANSWER,
&name);
for (rdataset = ISC_LIST_HEAD(name->list);
rdataset != NULL;
rdataset = ISC_LIST_NEXT(rdataset,
link)) {
if (rdataset->type ==
dns_rdatatype_cname &&
dns_rdataset_count(rdataset) > 1) {
*resultp = multiplecname;
goto found;
}
}
result = dns_message_nextname(rmessage,
DNS_SECTION_ANSWER);
}
}
if (rmessage->counts[DNS_SECTION_AUTHORITY] > 0) {
result = dns_message_firstname(rmessage,
DNS_SECTION_AUTHORITY);
while (result == ISC_R_SUCCESS) {
/*
* Check to see if the response has multiple
* SOA RRs. Update the result code if so.
*/
name = NULL;
dns_message_currentname(rmessage,
DNS_SECTION_AUTHORITY,
&name);
for (rdataset = ISC_LIST_HEAD(name->list);
rdataset != NULL;
rdataset = ISC_LIST_NEXT(rdataset,
link)) {
if (rdataset->type ==
dns_rdatatype_soa &&
dns_rdataset_count(rdataset) > 1) {
*resultp = multiplesoa;
goto found;
}
}
result = dns_message_nextname(rmessage,
DNS_SECTION_AUTHORITY);
}
}
} else if (rev->result == ISC_R_TIMEDOUT)
*resultp = timedout;
else {
fprintf(stderr, "unexpected result: %d (domain=%s, server=",
rev->result, trans->domain);
print_address(stderr, &server->address);
fputc('\n', stderr);
*resultp = unexpected;
}
found:
INSIST(*resultp != none);
if (type == dns_rdatatype_a && *resultp == exist)
trans->qname_found = ISC_TRUE;
dns_client_destroyreqtrans(&trans->reqid);
isc_event_free(&event);
dns_message_reset(trans->rmessage, DNS_MESSAGE_INTENTPARSE);
result = probe_name(trans, type);
if (result == ISC_R_NOMORE) {
/* We've tried all addresses of all servers. */
if (type == dns_rdatatype_a && trans->qname_found) {
/*
* If we've explored A RRs and found an existent
* record, we can move to AAAA.
*/
trans->current_ns = ISC_LIST_HEAD(trans->nslist);
probe_name(trans, dns_rdatatype_aaaa);
result = ISC_R_SUCCESS;
} else if (type == dns_rdatatype_a) {
/*
* No server provided an existent A RR of this name.
* Try next label.
*/
dns_fixedname_invalidate(&trans->fixedname);
trans->qname = NULL;
result = set_nextqname(trans);
if (result == ISC_R_SUCCESS) {
trans->current_ns =
ISC_LIST_HEAD(trans->nslist);
for (pns = trans->current_ns; pns != NULL;
pns = ISC_LIST_NEXT(pns, link)) {
for (server = ISC_LIST_HEAD(pns->servers);
server != NULL;
server = ISC_LIST_NEXT(server,
link)) {
INSIST(server->result_aaaa ==
none);
server->result_a = none;
}
}
result = probe_name(trans, dns_rdatatype_a);
}
}
if (result != ISC_R_SUCCESS) {
/*
* We've explored AAAA RRs or failed to find a valid
* query label. Wrap up the result and move to the
* next domain.
*/
reset_probe(trans);
}
} else if (result != ISC_R_SUCCESS)
reset_probe(trans); /* XXX */
}
