static void
log_rr(dns_name_t *name, dns_rdata_t *rdata, isc_uint32_t ttl) {
isc_result_t result;
isc_buffer_t buf;
char mem[2000];
dns_rdatalist_t rdl;
dns_rdataset_t rds;
dns_rdata_t rd = DNS_RDATA_INIT;
rdl.type = rdata->type;
rdl.rdclass = rdata->rdclass;
rdl.ttl = ttl;
if (rdata->type == dns_rdatatype_sig ||
rdata->type == dns_rdatatype_rrsig)
rdl.covers = dns_rdata_covers(rdata);
else
rdl.covers = dns_rdatatype_none;
ISC_LIST_INIT(rdl.rdata);
ISC_LINK_INIT(&rdl, link);
dns_rdataset_init(&rds);
dns_rdata_init(&rd);
dns_rdata_clone(rdata, &rd);
ISC_LIST_APPEND(rdl.rdata, &rd, link);
RUNTIME_CHECK(dns_rdatalist_tordataset(&rdl, &rds) == ISC_R_SUCCESS);
isc_buffer_init(&buf, mem, sizeof(mem));
result = dns_rdataset_totext(&rds, name,
ISC_FALSE, ISC_FALSE, &buf);
/*
* We could use xfrout_log(), but that would produce
* very long lines with a repetitive prefix.
*/
if (result == ISC_R_SUCCESS) {
/*
* Get rid of final newline.
*/
INSIST(buf.used >= 1 &&
((char *) buf.base)[buf.used - 1] == '\n');
buf.used--;
isc_log_write(XFROUT_RR_LOGARGS, "%.*s",
(int)isc_buffer_usedlength(&buf),
(char *)isc_buffer_base(&buf));
} else {
isc_log_write(XFROUT_RR_LOGARGS, "<RR too large to print>");
}
}
/*
* Arrange to send as much as we can of "stream" without blocking.
*
* Requires:
* The stream iterator is initialized and points at an RR,
* or possibly at the end of the stream (that is, the
* _first method of the iterator has been called).
*/
static void
sendstream(xfrout_ctx_t *xfr) {
dns_message_t *tcpmsg = NULL;
dns_message_t *msg = NULL; /* Client message if UDP, tcpmsg if TCP */
isc_result_t result;
isc_region_t used;
isc_region_t region;
dns_rdataset_t *qrdataset;
dns_name_t *msgname = NULL;
dns_rdata_t *msgrdata = NULL;
dns_rdatalist_t *msgrdl = NULL;
dns_rdataset_t *msgrds = NULL;
dns_compress_t cctx;
isc_boolean_t cleanup_cctx = ISC_FALSE;
isc_boolean_t is_tcp;
int n_rrs;
isc_buffer_clear(&xfr->buf);
isc_buffer_clear(&xfr->txlenbuf);
isc_buffer_clear(&xfr->txbuf);
is_tcp = ISC_TF((xfr->client->attributes & NS_CLIENTATTR_TCP) != 0);
if (!is_tcp) {
/*
* In the UDP case, we put the response data directly into
* the client message.
*/
msg = xfr->client->message;
CHECK(dns_message_reply(msg, ISC_TRUE));
} else {
/*
* TCP. Build a response dns_message_t, temporarily storing
* the raw, uncompressed owner names and RR data contiguously
* in xfr->buf. We know that if the uncompressed data fits
* in xfr->buf, the compressed data will surely fit in a TCP
* message.
*/
CHECK(dns_message_create(xfr->mctx,
DNS_MESSAGE_INTENTRENDER, &tcpmsg));
msg = tcpmsg;
msg->id = xfr->id;
msg->rcode = dns_rcode_noerror;
msg->flags = DNS_MESSAGEFLAG_QR | DNS_MESSAGEFLAG_AA;
if ((xfr->client->attributes & NS_CLIENTATTR_RA) != 0)
msg->flags |= DNS_MESSAGEFLAG_RA;
CHECK(dns_message_settsigkey(msg, xfr->tsigkey));
CHECK(dns_message_setquerytsig(msg, xfr->lasttsig));
if (xfr->lasttsig != NULL)
isc_buffer_free(&xfr->lasttsig);
/*
* Add a EDNS option to the message?
*/
if ((xfr->client->attributes & NS_CLIENTATTR_WANTOPT) != 0) {
dns_rdataset_t *opt = NULL;
CHECK(ns_client_addopt(xfr->client, msg, &opt));
CHECK(dns_message_setopt(msg, opt));
/*
* Add to first message only.
*/
xfr->client->attributes &= ~NS_CLIENTATTR_WANTNSID;
xfr->client->attributes &= ~NS_CLIENTATTR_HAVEEXPIRE;
}
/*
* Account for reserved space.
*/
if (xfr->tsigkey != NULL)
INSIST(msg->reserved != 0U);
isc_buffer_add(&xfr->buf, msg->reserved);
/*
* Include a question section in the first message only.
* BIND 8.2.1 will not recognize an IXFR if it does not
* have a question section.
*/
if (xfr->nmsg == 0) {
dns_name_t *qname = NULL;
isc_region_t r;
/*
* Reserve space for the 12-byte message header
* and 4 bytes of question.
*/
isc_buffer_add(&xfr->buf, 12 + 4);
qrdataset = NULL;
result = dns_message_gettemprdataset(msg, &qrdataset);
if (result != ISC_R_SUCCESS)
goto failure;
dns_rdataset_makequestion(qrdataset,
xfr->client->message->rdclass,
xfr->qtype);
result = dns_message_gettempname(msg, &qname);
if (result != ISC_R_SUCCESS)
goto failure;
dns_name_init(qname, NULL);
isc_buffer_availableregion(&xfr->buf, &r);
INSIST(r.length >= xfr->qname->length);
r.length = xfr->qname->length;
isc_buffer_putmem(&xfr->buf, xfr->qname->ndata,
xfr->qname->length);
dns_name_fromregion(qname, &r);
ISC_LIST_INIT(qname->list);
ISC_LIST_APPEND(qname->list, qrdataset, link);
dns_message_addname(msg, qname, DNS_SECTION_QUESTION);
} else {
/*
* Reserve space for the 12-byte message header
*/
isc_buffer_add(&xfr->buf, 12);
msg->tcp_continuation = 1;
}
}
/*
* Try to fit in as many RRs as possible, unless "one-answer"
* format has been requested.
*/
for (n_rrs = 0; ; n_rrs++) {
dns_name_t *name = NULL;
isc_uint32_t ttl;
dns_rdata_t *rdata = NULL;
unsigned int size;
isc_region_t r;
msgname = NULL;
msgrdata = NULL;
msgrdl = NULL;
msgrds = NULL;
xfr->stream->methods->current(xfr->stream,
&name, &ttl, &rdata);
size = name->length + 10 + rdata->length;
isc_buffer_availableregion(&xfr->buf, &r);
if (size >= r.length) {
/*
* RR would not fit. If there are other RRs in the
* buffer, send them now and leave this RR to the
* next message. If this RR overflows the buffer
* all by itself, fail.
*
* In theory some RRs might fit in a TCP message
* when compressed even if they do not fit when
* uncompressed, but surely we don't want
* to send such monstrosities to an unsuspecting
* slave.
*/
if (n_rrs == 0) {
xfrout_log(xfr, ISC_LOG_WARNING,
"RR too large for zone transfer "
"(%d bytes)", size);
/* XXX DNS_R_RRTOOLARGE? */
result = ISC_R_NOSPACE;
goto failure;
}
break;
}
if (isc_log_wouldlog(ns_g_lctx, XFROUT_RR_LOGLEVEL))
log_rr(name, rdata, ttl); /* XXX */
result = dns_message_gettempname(msg, &msgname);
if (result != ISC_R_SUCCESS)
goto failure;
dns_name_init(msgname, NULL);
isc_buffer_availableregion(&xfr->buf, &r);
INSIST(r.length >= name->length);
r.length = name->length;
isc_buffer_putmem(&xfr->buf, name->ndata, name->length);
dns_name_fromregion(msgname, &r);
/* Reserve space for RR header. */
isc_buffer_add(&xfr->buf, 10);
result = dns_message_gettemprdata(msg, &msgrdata);
if (result != ISC_R_SUCCESS)
goto failure;
isc_buffer_availableregion(&xfr->buf, &r);
r.length = rdata->length;
isc_buffer_putmem(&xfr->buf, rdata->data, rdata->length);
dns_rdata_init(msgrdata);
dns_rdata_fromregion(msgrdata,
rdata->rdclass, rdata->type, &r);
result = dns_message_gettemprdatalist(msg, &msgrdl);
if (result != ISC_R_SUCCESS)
goto failure;
msgrdl->type = rdata->type;
msgrdl->rdclass = rdata->rdclass;
msgrdl->ttl = ttl;
if (rdata->type == dns_rdatatype_sig ||
rdata->type == dns_rdatatype_rrsig)
msgrdl->covers = dns_rdata_covers(rdata);
else
msgrdl->covers = dns_rdatatype_none;
ISC_LIST_APPEND(msgrdl->rdata, msgrdata, link);
result = dns_message_gettemprdataset(msg, &msgrds);
if (result != ISC_R_SUCCESS)
goto failure;
result = dns_rdatalist_tordataset(msgrdl, msgrds);
INSIST(result == ISC_R_SUCCESS);
ISC_LIST_APPEND(msgname->list, msgrds, link);
dns_message_addname(msg, msgname, DNS_SECTION_ANSWER);
msgname = NULL;
result = xfr->stream->methods->next(xfr->stream);
if (result == ISC_R_NOMORE) {
xfr->end_of_stream = ISC_TRUE;
break;
}
CHECK(result);
if (! xfr->many_answers)
break;
/*
* At this stage, at least 1 RR has been rendered into
* the message. Check if we want to clamp this message
* here (TCP only). 20480 was set as an upper limit to
* improve message compression.
*/
if ((isc_buffer_usedlength(&xfr->buf) >= 20480) && is_tcp)
break;
}
if (is_tcp) {
CHECK(dns_compress_init(&cctx, -1, xfr->mctx));
dns_compress_setsensitive(&cctx, ISC_TRUE);
cleanup_cctx = ISC_TRUE;
CHECK(dns_message_renderbegin(msg, &cctx, &xfr->txbuf));
CHECK(dns_message_rendersection(msg, DNS_SECTION_QUESTION, 0));
CHECK(dns_message_rendersection(msg, DNS_SECTION_ANSWER, 0));
CHECK(dns_message_renderend(msg));
dns_compress_invalidate(&cctx);
cleanup_cctx = ISC_FALSE;
isc_buffer_usedregion(&xfr->txbuf, &used);
isc_buffer_putuint16(&xfr->txlenbuf,
(isc_uint16_t)used.length);
region.base = xfr->txlenbuf.base;
region.length = 2 + used.length;
xfrout_log(xfr, ISC_LOG_DEBUG(8),
"sending TCP message of %d bytes",
used.length);
CHECK(isc_socket_send(xfr->client->tcpsocket, /* XXX */
®ion, xfr->client->task,
xfrout_senddone,
xfr));
xfr->sends++;
} else {
xfrout_log(xfr, ISC_LOG_DEBUG(8), "sending IXFR UDP response");
ns_client_send(xfr->client);
xfr->stream->methods->pause(xfr->stream);
xfrout_ctx_destroy(&xfr);
return;
}
/* Advance lasttsig to be the last TSIG generated */
CHECK(dns_message_getquerytsig(msg, xfr->mctx, &xfr->lasttsig));
xfr->nmsg++;
failure:
if (msgname != NULL) {
if (msgrds != NULL) {
if (dns_rdataset_isassociated(msgrds))
dns_rdataset_disassociate(msgrds);
dns_message_puttemprdataset(msg, &msgrds);
}
if (msgrdl != NULL) {
ISC_LIST_UNLINK(msgrdl->rdata, msgrdata, link);
dns_message_puttemprdatalist(msg, &msgrdl);
}
if (msgrdata != NULL)
dns_message_puttemprdata(msg, &msgrdata);
dns_message_puttempname(msg, &msgname);
}
if (tcpmsg != NULL)
dns_message_destroy(&tcpmsg);
if (cleanup_cctx)
dns_compress_invalidate(&cctx);
/*
* Make sure to release any locks held by database
* iterators before returning from the event handler.
*/
xfr->stream->methods->pause(xfr->stream);
if (result == ISC_R_SUCCESS)
return;
xfrout_fail(xfr, result, "sending zone data");
}
static dns_rdatatype_t
rdata_covers(dns_rdata_t *rdata) {
return (rdata->type == dns_rdatatype_rrsig ?
dns_rdata_covers(rdata) : 0);
}
