1 files changed, 466 insertions, 0 deletions
diff --git a/src/lib/dns/rrset.cc b/src/lib/dns/rrset.cc
new file mode 100644
index 0000000..b217002
--- /dev/null
+++ b/src/lib/dns/rrset.cc
@@ -0,0 +1,466 @@
+// Copyright (C) 2010-2021 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 <algorithm>
+#include <string>
+#include <vector>
+
+#include <boost/shared_ptr.hpp>
+#include <boost/foreach.hpp>
+
+#include <util/buffer.h>
+#include <dns/messagerenderer.h>
+#include <dns/name.h>
+#include <dns/rrclass.h>
+#include <dns/rrtype.h>
+#include <dns/rrttl.h>
+#include <dns/rrset.h>
+
+using namespace std;
+using namespace isc::dns;
+using namespace isc::util;
+using namespace isc::dns::rdata;
+
+namespace isc {
+namespace dns {
+void
+AbstractRRset::addRdata(const Rdata& rdata) {
+    addRdata(createRdata(getType(), getClass(), rdata));
+}
+
+string
+AbstractRRset::toText() const {
+    string s;
+    RdataIteratorPtr it = getRdataIterator();
+
+    // In the case of an empty rrset, just print name, ttl, class, and
+    // type
+    if (it->isLast()) {
+        // But only for class ANY or NONE
+        if (getClass() != RRClass::ANY() &&
+            getClass() != RRClass::NONE()) {
+            isc_throw(EmptyRRset, "toText() is attempted for an empty RRset");
+        }
+
+        s += getName().toText() + " " + getTTL().toText() + " " +
+             getClass().toText() + " " + getType().toText() + "\n";
+        return (s);
+    }
+
+    do {
+        s += getName().toText() + " " + getTTL().toText() + " " +
+             getClass().toText() + " " + getType().toText() + " " +
+             it->getCurrent().toText() + "\n";
+        it->next();
+    } while (!it->isLast());
+
+    if (getRRsig()) {
+        s += getRRsig()->toText();
+    }
+
+    return (s);
+}
+
+namespace { // unnamed namespace
+
+// FIXME: This method's code should somehow be unified with
+// BasicRRsetImpl::toWire() below to avoid duplication.
+template <typename T>
+inline unsigned int
+rrsetToWire(const AbstractRRset& rrset, T& output, const size_t limit) {
+    unsigned int n = 0;
+    RdataIteratorPtr it = rrset.getRdataIterator();
+
+    if (it->isLast()) {
+        // empty rrsets are only allowed for classes ANY and NONE
+        if (rrset.getClass() != RRClass::ANY() &&
+            rrset.getClass() != RRClass::NONE()) {
+            isc_throw(EmptyRRset, "toWire() is attempted for an empty RRset");
+        }
+
+        // For an empty RRset, write the name, type, class and TTL once,
+        // followed by empty rdata.
+        rrset.getName().toWire(output);
+        rrset.getType().toWire(output);
+        rrset.getClass().toWire(output);
+        rrset.getTTL().toWire(output);
+        output.writeUint16(0);
+        // Still counts as 1 'rr'; it does show up in the message
+        return (1);
+    }
+
+    // sort the set of Rdata based on rrset-order and sortlist, and possible
+    // other options.  Details to be considered.
+    do {
+        const size_t pos0 = output.getLength();
+        assert(pos0 < 65536);
+
+        rrset.getName().toWire(output);
+        rrset.getType().toWire(output);
+        rrset.getClass().toWire(output);
+        rrset.getTTL().toWire(output);
+
+        const size_t pos = output.getLength();
+        output.skip(sizeof(uint16_t)); // leave the space for RDLENGTH
+        it->getCurrent().toWire(output);
+        output.writeUint16At(output.getLength() - pos - sizeof(uint16_t), pos);
+
+        if (limit > 0 && output.getLength() > limit) {
+            // truncation is needed
+            output.trim(output.getLength() - pos0);
+            return (n);
+        }
+
+        it->next();
+        ++n;
+    } while (!it->isLast());
+
+    return (n);
+}
+
+} // end of unnamed namespace
+
+unsigned int
+AbstractRRset::toWire(OutputBuffer& buffer) const {
+    return (rrsetToWire<OutputBuffer>(*this, buffer, 0));
+}
+
+unsigned int
+AbstractRRset::toWire(AbstractMessageRenderer& renderer) const {
+    const unsigned int rrs_written = rrsetToWire<AbstractMessageRenderer>(
+        *this, renderer, renderer.getLengthLimit());
+    if (getRdataCount() > rrs_written) {
+        renderer.setTruncated();
+    }
+    return (rrs_written);
+}
+
+bool
+AbstractRRset::isSameKind(const AbstractRRset& other) const {
+  // Compare classes last as they're likely to be identical. Compare
+  // names late in the list too, as these are expensive. So we compare
+  // types first, names second and classes last.
+  return (getType() == other.getType() &&
+          getName() == other.getName() &&
+          getClass() == other.getClass());
+}
+
+ostream&
+operator<<(ostream& os, const AbstractRRset& rrset) {
+    os << rrset.toText();
+    return (os);
+}
+
+/// \brief This encapsulates the actual implementation of the \c BasicRRset
+/// class.  It's hidden from applications.
+class BasicRRsetImpl {
+public:
+    BasicRRsetImpl(const Name& name, const RRClass& rrclass,
+                   const RRType& rrtype, const RRTTL& ttl) :
+        name_(name), rrclass_(rrclass), rrtype_(rrtype), ttl_(ttl) {}
+
+    unsigned int toWire(AbstractMessageRenderer& renderer, size_t limit) const;
+
+    Name name_;
+    RRClass rrclass_;
+    RRType rrtype_;
+    RRTTL ttl_;
+    // XXX: "list" is not a good name: It in fact isn't a list; more conceptual
+    // name than a data structure name is generally better.  But since this
+    // is only used in the internal implementation we'll live with it.
+    vector<ConstRdataPtr> rdatalist_;
+};
+
+// FIXME: This method's code should somehow be unified with
+// rrsetToWire() above to avoid duplication.
+unsigned int
+BasicRRsetImpl::toWire(AbstractMessageRenderer& renderer, size_t limit) const {
+    if (rdatalist_.empty()) {
+        // empty rrsets are only allowed for classes ANY and NONE
+        if (rrclass_ != RRClass::ANY() &&
+            rrclass_ != RRClass::NONE()) {
+            isc_throw(EmptyRRset, "toWire() is attempted for an empty RRset");
+        }
+
+        // For an empty RRset, write the name, type, class and TTL once,
+        // followed by empty rdata.
+        name_.toWire(renderer);
+        rrtype_.toWire(renderer);
+        rrclass_.toWire(renderer);
+        ttl_.toWire(renderer);
+        renderer.writeUint16(0);
+        // Still counts as 1 'rr'; it does show up in the message
+        return (1);
+    }
+
+    unsigned int n = 0;
+
+    // sort the set of Rdata based on rrset-order and sortlist, and possible
+    // other options.  Details to be considered.
+    BOOST_FOREACH(const ConstRdataPtr& rdata, rdatalist_) {
+        const size_t pos0 = renderer.getLength();
+        assert(pos0 < 65536);
+
+        name_.toWire(renderer);
+        rrtype_.toWire(renderer);
+        rrclass_.toWire(renderer);
+        ttl_.toWire(renderer);
+
+        const size_t pos = renderer.getLength();
+        renderer.skip(sizeof(uint16_t)); // leave the space for RDLENGTH
+        rdata->toWire(renderer);
+        renderer.writeUint16At(renderer.getLength() - pos - sizeof(uint16_t),
+                               pos);
+
+        if (limit > 0 && renderer.getLength() > limit) {
+            // truncation is needed
+            renderer.trim(renderer.getLength() - pos0);
+            return (n);
+        }
+        ++n;
+    }
+
+    return (n);
+}
+
+BasicRRset::BasicRRset(const Name& name, const RRClass& rrclass,
+                       const RRType& rrtype, const RRTTL& ttl)
+{
+    impl_ = new BasicRRsetImpl(name, rrclass, rrtype, ttl);
+}
+
+BasicRRset::~BasicRRset() {
+    delete impl_;
+}
+
+void
+BasicRRset::addRdata(ConstRdataPtr rdata) {
+    impl_->rdatalist_.push_back(rdata);
+}
+
+void
+BasicRRset::addRdata(const Rdata& rdata) {
+    AbstractRRset::addRdata(rdata);
+}
+
+void
+BasicRRset::addRdata(const std::string& rdata_str) {
+    addRdata(createRdata(getType(), getClass(), rdata_str));
+}
+
+unsigned int
+BasicRRset::getRdataCount() const {
+    return (impl_->rdatalist_.size());
+}
+
+const Name&
+BasicRRset::getName() const {
+    return (impl_->name_);
+}
+
+const RRClass&
+BasicRRset::getClass() const {
+    return (impl_->rrclass_);
+}
+
+const RRType&
+BasicRRset::getType() const {
+    return (impl_->rrtype_);
+}
+
+const RRTTL&
+BasicRRset::getTTL() const {
+    return (impl_->ttl_);
+}
+
+void
+BasicRRset::setTTL(const RRTTL& ttl) {
+    impl_->ttl_ = ttl;
+}
+
+string
+BasicRRset::toText() const {
+    return (AbstractRRset::toText());
+}
+
+uint16_t
+BasicRRset::getLength() const {
+    uint16_t length = 0;
+    RdataIteratorPtr it = getRdataIterator();
+
+    if (it->isLast()) {
+        // empty rrsets are only allowed for classes ANY and NONE
+        if (getClass() != RRClass::ANY() &&
+            getClass() != RRClass::NONE()) {
+            isc_throw(EmptyRRset, "getLength() is attempted for an empty RRset");
+        }
+
+        // For an empty RRset, write the name, type, class and TTL once,
+        // followed by empty rdata.
+        length += getName().getLength();
+        length += 2; // TYPE field
+        length += 2; // CLASS field
+        length += 4; // TTL field
+        length += 2; // RDLENGTH field (=0 in wire format)
+
+        return (length);
+    }
+
+    do {
+        // This is a size_t as some of the following additions may
+        // overflow due to a programming mistake somewhere.
+        size_t rrlen = 0;
+
+        rrlen += getName().getLength();
+        rrlen += 2; // TYPE field
+        rrlen += 2; // CLASS field
+        rrlen += 4; // TTL field
+        rrlen += 2; // RDLENGTH field
+        rrlen += it->getCurrent().getLength();
+
+        assert(length + rrlen < 65536);
+        length += rrlen;
+
+        it->next();
+    } while (!it->isLast());
+
+    return (length);
+}
+
+unsigned int
+BasicRRset::toWire(OutputBuffer& buffer) const {
+    return (AbstractRRset::toWire(buffer));
+}
+
+unsigned int
+BasicRRset::toWire(AbstractMessageRenderer& renderer) const {
+    const unsigned int rrs_written = impl_->toWire(renderer,
+                                                   renderer.getLengthLimit());
+    if (impl_->rdatalist_.size() > rrs_written) {
+        renderer.setTruncated();
+    }
+    return (rrs_written);
+}
+
+RRset::RRset(const Name& name, const RRClass& rrclass,
+            const RRType& rrtype, const RRTTL& ttl) :
+    BasicRRset(name, rrclass, rrtype, ttl)
+{
+    rrsig_ = RRsetPtr();
+}
+
+RRset::~RRset() {}
+
+unsigned int
+RRset::getRRsigDataCount() const {
+    if (rrsig_) {
+        return (rrsig_->getRdataCount());
+    } else {
+        return (0);
+    }
+}
+
+uint16_t
+RRset::getLength() const {
+    uint16_t length = BasicRRset::getLength();
+
+    if (rrsig_) {
+        const uint16_t rrsigs_length = rrsig_->getLength();
+        // the uint16_ts are promoted to ints during addition below, so
+        // it won't overflow a 16-bit register.
+        assert(length + rrsigs_length < 65536);
+        length += rrsigs_length;
+    }
+
+    return (length);
+}
+
+unsigned int
+RRset::toWire(OutputBuffer& buffer) const {
+    unsigned int rrs_written = BasicRRset::toWire(buffer);
+    if (getRdataCount() > rrs_written) {
+        return (rrs_written);
+    }
+
+    if (rrsig_) {
+        rrs_written += rrsig_->toWire(buffer);
+    }
+
+    return (rrs_written);
+}
+
+unsigned int
+RRset::toWire(AbstractMessageRenderer& renderer) const {
+    unsigned int rrs_written = BasicRRset::toWire(renderer);
+    if (getRdataCount() > rrs_written) {
+        return (rrs_written);
+    }
+
+    if (rrsig_) {
+        rrs_written += rrsig_->toWire(renderer);
+
+        if (getRdataCount() + getRRsigDataCount() > rrs_written) {
+            renderer.setTruncated();
+        }
+    }
+
+    return (rrs_written);
+}
+
+namespace {
+
+class BasicRdataIterator : public RdataIterator {
+public:
+    /// @brief Constructor.
+    BasicRdataIterator(const std::vector<rdata::ConstRdataPtr>& datavector) :
+        datavector_(&datavector), it_(datavector_->begin()) {}
+
+    /// @brief Destructor.
+    ~BasicRdataIterator() {}
+
+    /// @brief Set iterator at first position.
+    virtual void first() {
+        it_ = datavector_->begin();
+    }
+
+    /// @brief Advance iterator.
+    virtual void next() {
+        ++it_;
+    }
+
+    /// @brief Get value at current iterator position.
+    ///
+    /// @return The value at current iterator position.
+    virtual const rdata::Rdata& getCurrent() const {
+        return (**it_);
+    }
+
+    /// @brief Check if iterator has reached the end.
+    ///
+    /// @return true if iterator has reached the end, false otherwise.
+    virtual bool isLast() const {
+        return (it_ == datavector_->end());
+    }
+
+private:
+    /// @brief Vector containing data.
+    const std::vector<rdata::ConstRdataPtr>* datavector_;
+
+    /// @brief Iterator used to retrieve data.
+    std::vector<rdata::ConstRdataPtr>::const_iterator it_;
+};
+
+}
+
+RdataIteratorPtr
+BasicRRset::getRdataIterator() const {
+    return (RdataIteratorPtr(new BasicRdataIterator(impl_->rdatalist_)));
+}
+
+}
+}