1 files changed, 142 insertions, 0 deletions
diff --git a/src/lib/dns/tsigrecord.cc b/src/lib/dns/tsigrecord.cc
new file mode 100644
index 0000000..483296d
--- /dev/null
+++ b/src/lib/dns/tsigrecord.cc
@@ -0,0 +1,142 @@
+// Copyright (C) 2011-2015 Internet Systems Consortium, Inc. ("ISC")
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#include <config.h>
+
+#include <ostream>
+#include <string>
+
+#include <util/buffer.h>
+
+#include <dns/exceptions.h>
+#include <dns/messagerenderer.h>
+#include <dns/rrclass.h>
+#include <dns/rrttl.h>
+#include <dns/tsigrecord.h>
+
+using namespace isc::util;
+using namespace isc::dns::rdata;
+
+namespace {
+// Internally used constants:
+
+// Size in octets for the RR type, class TTL, RDLEN fields.
+const size_t RR_COMMON_LEN = 10;
+
+// Size in octets for the fixed part of TSIG RDATAs.
+// - Time Signed (6)
+// - Fudge (2)
+// - MAC Size (2)
+// - Original ID (2)
+// - Error (2)
+// - Other Len (2)
+const size_t RDATA_COMMON_LEN = 16;
+}
+
+namespace isc {
+namespace dns {
+TSIGRecord::TSIGRecord(const Name& key_name,
+                       const rdata::any::TSIG& tsig_rdata) :
+    key_name_(key_name), rdata_(tsig_rdata),
+    length_(RR_COMMON_LEN + RDATA_COMMON_LEN + key_name_.getLength() +
+            rdata_.getAlgorithm().getLength() +
+            rdata_.getMACSize() + rdata_.getOtherLen())
+{}
+
+namespace {
+// This is a straightforward wrapper of dynamic_cast<const any::TSIG&>.
+// We use this so that we can throw the DNSMessageFORMERR exception when
+// unexpected type of RDATA is detected in the member initialization list
+// of the constructor below.
+const any::TSIG&
+castToTSIGRdata(const rdata::Rdata& rdata) {
+    const any::TSIG* tsig_rdata =
+        dynamic_cast<const any::TSIG*>(&rdata);
+    if (!tsig_rdata) {
+        isc_throw(DNSMessageFORMERR,
+                  "TSIG record is being constructed from "
+                  "incompatible RDATA: " << rdata.toText());
+    }
+    return (*tsig_rdata);
+}
+}
+
+TSIGRecord::TSIGRecord(const Name& name, const RRClass& rrclass,
+                       const RRTTL& ttl, const rdata::Rdata& rdata,
+                       size_t length) :
+    key_name_(name), rdata_(castToTSIGRdata(rdata)), length_(length)
+{
+    if (rrclass != getClass()) {
+        isc_throw(DNSMessageFORMERR, "Unexpected TSIG RR class: " << rrclass);
+    }
+    if (ttl != RRTTL(TSIG_TTL)) {
+        isc_throw(DNSMessageFORMERR, "Unexpected TSIG TTL: " << ttl);
+    }
+}
+
+const RRClass&
+TSIGRecord::getClass() {
+    return (RRClass::ANY());
+}
+
+const RRTTL&
+TSIGRecord::getTTL() {
+    static RRTTL ttl(TSIG_TTL);
+    return (ttl);
+}
+
+namespace {
+template <typename OUTPUT>
+void
+toWireCommon(OUTPUT& output, const rdata::any::TSIG& rdata) {
+    // RR type, class, TTL are fixed constants.
+    RRType::TSIG().toWire(output);
+    TSIGRecord::getClass().toWire(output);
+    output.writeUint32(TSIGRecord::TSIG_TTL);
+
+    // RDLEN
+    output.writeUint16(RDATA_COMMON_LEN + rdata.getAlgorithm().getLength() +
+                       rdata.getMACSize() + rdata.getOtherLen());
+
+    // TSIG RDATA
+    rdata.toWire(output);
+}
+}
+
+int
+TSIGRecord::toWire(AbstractMessageRenderer& renderer) const {
+    // If adding the TSIG would exceed the size limit, don't do it.
+    if (renderer.getLength() + length_ > renderer.getLengthLimit()) {
+        renderer.setTruncated();
+        return (0);
+    }
+
+    // key name = owner.  note that we disable compression.
+    renderer.writeName(key_name_, false);
+    toWireCommon(renderer, rdata_);
+    return (1);
+}
+
+int
+TSIGRecord::toWire(OutputBuffer& buffer) const {
+    key_name_.toWire(buffer);
+    toWireCommon(buffer, rdata_);
+    return (1);
+}
+
+std::string
+TSIGRecord::toText() const {
+    return (key_name_.toText() + " " + RRTTL(TSIG_TTL).toText() + " " +
+            getClass().toText() + " " + RRType::TSIG().toText() + " " +
+            rdata_.toText() + "\n");
+}
+
+std::ostream&
+operator<<(std::ostream& os, const TSIGRecord& record) {
+    return (os << record.toText());
+}
+} // namespace dns
+} // namespace isc