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// 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 <iostream>
#include <sstream>
#include <boost/lexical_cast.hpp>
#include <util/buffer.h>
#include <util/strutil.h>
#include <dns/messagerenderer.h>
#include <dns/name.h>
#include <dns/rdata.h>
#include <dns/rdataclass.h>
#include <dns/rdata/generic/detail/lexer_util.h>
using namespace std;
using namespace isc::util;
using namespace isc::util::str;
using isc::dns::rdata::generic::detail::createNameFromLexer;
// BEGIN_ISC_NAMESPACE
// BEGIN_RDATA_NAMESPACE
struct SRVImpl {
// straightforward representation of SRV RDATA fields
SRVImpl(uint16_t priority, uint16_t weight, uint16_t port,
const Name& target) :
priority_(priority), weight_(weight), port_(port),
target_(target)
{}
uint16_t priority_;
uint16_t weight_;
uint16_t port_;
Name target_;
};
/// \brief Constructor from string.
///
/// The given string must represent a valid SRV RDATA. There can be extra
/// space characters at the beginning or end of the text (which are simply
/// ignored), but other extra text, including a new line, will make the
/// construction fail with an exception.
///
/// The TARGET name must be absolute since there's no parameter that
/// specifies the origin name; if it is not absolute, \c MissingNameOrigin
/// exception will be thrown. It must not be represented as a quoted
/// string.
///
/// See the construction that takes \c MasterLexer for other fields.
///
/// \throw Others Exception from the Name and RRTTL constructors.
/// \throw InvalidRdataText Other general syntax errors.
SRV::SRV(const std::string& srv_str) :
impl_(NULL)
{
try {
std::istringstream ss(srv_str);
MasterLexer lexer;
lexer.pushSource(ss);
uint32_t num = lexer.getNextToken(MasterToken::NUMBER).getNumber();
if (num > 65535) {
isc_throw(InvalidRdataText, "Invalid SRV priority in: " << srv_str);
}
const uint16_t priority = static_cast<uint16_t>(num);
num = lexer.getNextToken(MasterToken::NUMBER).getNumber();
if (num > 65535) {
isc_throw(InvalidRdataText, "Invalid SRV weight in: " << srv_str);
}
const uint16_t weight = static_cast<uint16_t>(num);
num = lexer.getNextToken(MasterToken::NUMBER).getNumber();
if (num > 65535) {
isc_throw(InvalidRdataText, "Invalid SRV port in: " << srv_str);
}
const uint16_t port = static_cast<uint16_t>(num);
const Name targetname = createNameFromLexer(lexer, NULL);
if (lexer.getNextToken().getType() != MasterToken::END_OF_FILE) {
isc_throw(InvalidRdataText, "extra input text for SRV: "
<< srv_str);
}
impl_ = new SRVImpl(priority, weight, port, targetname);
} catch (const MasterLexer::LexerError& ex) {
isc_throw(InvalidRdataText, "Failed to construct SRV from '" <<
srv_str << "': " << ex.what());
}
}
/// \brief Constructor from wire-format data.
///
/// When a read operation on \c buffer fails (e.g., due to a corrupted
/// message) a corresponding exception from the \c InputBuffer class will
/// be thrown.
/// If the wire-format data does not end with a valid domain name,
/// a corresponding exception from the \c Name class will be thrown.
/// In addition, this constructor internally involves resource allocation,
/// and if it fails a corresponding standard exception will be thrown.
///
/// According to RFC2782, the Target field must be a non compressed form
/// of domain name. But this implementation accepts a %SRV RR even if that
/// field is compressed as suggested in RFC3597.
///
/// \param buffer A buffer storing the wire format data.
/// \param rdata_len The length of the RDATA in bytes, normally expected
/// to be the value of the RDLENGTH field of the corresponding RR.
SRV::SRV(InputBuffer& buffer, size_t rdata_len) {
if (rdata_len < 6) {
isc_throw(InvalidRdataLength, "SRV too short");
}
const uint16_t priority = buffer.readUint16();
const uint16_t weight = buffer.readUint16();
const uint16_t port = buffer.readUint16();
const Name targetname(buffer);
impl_ = new SRVImpl(priority, weight, port, targetname);
}
/// \brief Constructor with a context of MasterLexer.
///
/// The \c lexer should point to the beginning of valid textual representation
/// of an SRV RDATA. The TARGET field can be non-absolute if \c origin
/// is non-NULL, in which case \c origin is used to make it absolute.
/// It must not be represented as a quoted string.
///
/// The PRIORITY, WEIGHT and PORT fields must each be a valid decimal
/// representation of an unsigned 16-bit integers respectively.
///
/// \throw MasterLexer::LexerError General parsing error such as missing field.
/// \throw Other Exceptions from the Name and RRTTL constructors if
/// construction of textual fields as these objects fail.
///
/// \param lexer A \c MasterLexer object parsing a master file for the
/// RDATA to be created
/// \param origin If non NULL, specifies the origin of TARGET when it
/// is non-absolute.
SRV::SRV(MasterLexer& lexer, const Name* origin,
MasterLoader::Options, MasterLoaderCallbacks&)
{
uint32_t num = lexer.getNextToken(MasterToken::NUMBER).getNumber();
if (num > 65535) {
isc_throw(InvalidRdataText, "Invalid SRV priority: " << num);
}
const uint16_t priority = static_cast<uint16_t>(num);
num = lexer.getNextToken(MasterToken::NUMBER).getNumber();
if (num > 65535) {
isc_throw(InvalidRdataText, "Invalid SRV weight: " << num);
}
const uint16_t weight = static_cast<uint16_t>(num);
num = lexer.getNextToken(MasterToken::NUMBER).getNumber();
if (num > 65535) {
isc_throw(InvalidRdataText, "Invalid SRV port: " << num);
}
const uint16_t port = static_cast<uint16_t>(num);
const Name targetname = createNameFromLexer(lexer, origin);
impl_ = new SRVImpl(priority, weight, port, targetname);
}
/// \brief The copy constructor.
///
/// It internally allocates a resource, and if it fails a corresponding
/// standard exception will be thrown.
/// This constructor never throws an exception otherwise.
SRV::SRV(const SRV& source) :
Rdata(), impl_(new SRVImpl(*source.impl_))
{}
SRV&
SRV::operator=(const SRV& source) {
if (this == &source) {
return (*this);
}
SRVImpl* newimpl = new SRVImpl(*source.impl_);
delete impl_;
impl_ = newimpl;
return (*this);
}
SRV::~SRV() {
delete impl_;
}
/// \brief Convert the \c SRV to a string.
///
/// The output of this method is formatted as described in the "from string"
/// constructor (\c SRV(const std::string&))).
///
/// If internal resource allocation fails, a corresponding
/// standard exception will be thrown.
///
/// \return A \c string object that represents the \c SRV object.
string
SRV::toText() const {
using boost::lexical_cast;
return (lexical_cast<string>(impl_->priority_) +
" " + lexical_cast<string>(impl_->weight_) +
" " + lexical_cast<string>(impl_->port_) +
" " + impl_->target_.toText());
}
/// \brief Render the \c SRV in the wire format without name compression.
///
/// If internal resource allocation fails, a corresponding
/// standard exception will be thrown.
/// This method never throws an exception otherwise.
///
/// \param buffer An output buffer to store the wire data.
void
SRV::toWire(OutputBuffer& buffer) const {
buffer.writeUint16(impl_->priority_);
buffer.writeUint16(impl_->weight_);
buffer.writeUint16(impl_->port_);
impl_->target_.toWire(buffer);
}
/// \brief Render the \c SRV in the wire format with taking into account
/// compression.
///
/// As specified in RFC2782, the Target field (a domain name) will not be
/// compressed. However, the domain name could be a target of compression
/// of other compressible names (though pretty unlikely), the offset
/// information of the algorithm name may be recorded in \c renderer.
///
/// If internal resource allocation fails, a corresponding
/// standard exception will be thrown.
/// This method never throws an exception otherwise.
///
/// \param renderer DNS message rendering context that encapsulates the
/// output buffer and name compression information.
void
SRV::toWire(AbstractMessageRenderer& renderer) const {
renderer.writeUint16(impl_->priority_);
renderer.writeUint16(impl_->weight_);
renderer.writeUint16(impl_->port_);
renderer.writeName(impl_->target_, false);
}
/// \brief Compare two instances of \c SRV RDATA.
///
/// See documentation in \c Rdata.
int
SRV::compare(const Rdata& other) const {
const SRV& other_srv = dynamic_cast<const SRV&>(other);
if (impl_->priority_ != other_srv.impl_->priority_) {
return (impl_->priority_ < other_srv.impl_->priority_ ? -1 : 1);
}
if (impl_->weight_ != other_srv.impl_->weight_) {
return (impl_->weight_ < other_srv.impl_->weight_ ? -1 : 1);
}
if (impl_->port_ != other_srv.impl_->port_) {
return (impl_->port_ < other_srv.impl_->port_ ? -1 : 1);
}
return (compareNames(impl_->target_, other_srv.impl_->target_));
}
uint16_t
SRV::getPriority() const {
return (impl_->priority_);
}
uint16_t
SRV::getWeight() const {
return (impl_->weight_);
}
uint16_t
SRV::getPort() const {
return (impl_->port_);
}
const Name&
SRV::getTarget() const {
return (impl_->target_);
}
// END_RDATA_NAMESPACE
// END_ISC_NAMESPACE
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