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// Copyright (C) 2011-2023 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 <dhcp/dhcp4.h>
#include <dhcp/libdhcp++.h>
#include <dhcp/option.h>
#include <dhcp/option_space.h>
#include <exceptions/exceptions.h>
#include <util/encode/hex.h>
#include <util/io_utilities.h>
#include <boost/make_shared.hpp>
#include <iomanip>
#include <list>
#include <sstream>
#include <arpa/inet.h>
#include <stdint.h>
#include <string.h>
using namespace std;
using namespace isc::util;
namespace isc {
namespace dhcp {
OptionPtr
Option::factory(Option::Universe u,
uint16_t type,
const OptionBuffer& buf) {
return (LibDHCP::optionFactory(u, type, buf));
}
Option::Option(Universe u, uint16_t type)
: universe_(u), type_(type) {
check();
}
Option::Option(Universe u, uint16_t type, const OptionBuffer& data)
: universe_(u), type_(type), data_(data) {
check();
}
Option::Option(Universe u, uint16_t type, OptionBufferConstIter first,
OptionBufferConstIter last)
: universe_(u), type_(type), data_(first, last) {
check();
}
Option::Option(const Option& option)
: universe_(option.universe_), type_(option.type_),
data_(option.data_), options_(),
encapsulated_space_(option.encapsulated_space_) {
option.getOptionsCopy(options_);
}
OptionPtr
Option::create(Universe u, uint16_t type) {
return (boost::make_shared<Option>(u, type));
}
OptionPtr
Option::create(Universe u, uint16_t type, const OptionBuffer& data) {
return (boost::make_shared<Option>(u, type, data));
}
Option&
Option::operator=(const Option& rhs) {
if (&rhs != this) {
universe_ = rhs.universe_;
type_ = rhs.type_;
data_ = rhs.data_;
rhs.getOptionsCopy(options_);
encapsulated_space_ = rhs.encapsulated_space_;
}
return (*this);
}
OptionPtr
Option::clone() const {
return (cloneInternal<Option>());
}
void
Option::check() const {
if ((universe_ != V4) && (universe_ != V6)) {
isc_throw(BadValue, "Invalid universe type specified. "
<< "Only V4 and V6 are allowed.");
}
if (universe_ == V4) {
if (type_ > 255) {
isc_throw(OutOfRange, "DHCPv4 Option type " << type_ << " is too big. "
<< "For DHCPv4 allowed type range is 0..255");
}
}
// no need to check anything for DHCPv6. It allows full range (0-64k) of
// both types and data size.
}
void Option::pack(isc::util::OutputBuffer& buf, bool check) const {
// Write a header.
packHeader(buf, check);
// Write data.
if (!data_.empty()) {
buf.writeData(&data_[0], data_.size());
}
// Write sub-options.
packOptions(buf, check);
}
void
Option::packHeader(isc::util::OutputBuffer& buf, bool check) const {
if (universe_ == V4) {
if (check && len() > 255) {
isc_throw(OutOfRange, "DHCPv4 Option " << type_ << " is too big. "
<< "At most 255 bytes are supported.");
}
buf.writeUint8(type_);
buf.writeUint8(len() - getHeaderLen());
} else {
buf.writeUint16(type_);
buf.writeUint16(len() - getHeaderLen());
}
}
void
Option::packOptions(isc::util::OutputBuffer& buf, bool check) const {
switch (universe_) {
case V4:
LibDHCP::packOptions4(buf, options_, false, check);
return;
case V6:
LibDHCP::packOptions6(buf, options_);
return;
default:
isc_throw(isc::BadValue, "Invalid universe type " << universe_);
}
}
void Option::unpack(OptionBufferConstIter begin,
OptionBufferConstIter end) {
setData(begin, end);
}
void
Option::unpackOptions(const OptionBuffer& buf) {
list<uint16_t> deferred;
switch (universe_) {
case V4:
LibDHCP::unpackOptions4(buf, getEncapsulatedSpace(),
options_, deferred,
getType() == DHO_VENDOR_ENCAPSULATED_OPTIONS);
return;
case V6:
LibDHCP::unpackOptions6(buf, getEncapsulatedSpace(), options_);
return;
default:
isc_throw(isc::BadValue, "Invalid universe type " << universe_);
}
}
uint16_t Option::len() const {
// Returns length of the complete option (data length + DHCPv4/DHCPv6
// option header)
// length of the whole option is header and data stored in this option...
size_t length = getHeaderLen() + data_.size();
// ... and sum of lengths of all suboptions
for (auto const& option : options_) {
length += option.second->len();
}
// note that this is not equal to length field. This value denotes
// number of bytes required to store this option. length option should
// contain (len()-getHeaderLen()) value.
return (static_cast<uint16_t>(length));
}
bool
Option::valid() const {
if (universe_ != V4 &&
universe_ != V6) {
return (false);
}
return (true);
}
OptionPtr Option::getOption(uint16_t opt_type) const {
auto const& x = options_.find(opt_type);
if (x != options_.end()) {
return (x->second);
}
return OptionPtr(); // NULL
}
void
Option::getOptionsCopy(OptionCollection& options_copy) const {
OptionCollection local_options;
for (auto const& option : options_) {
OptionPtr copy = option.second->clone();
local_options.insert(std::make_pair(option.second->getType(), copy));
}
// All options copied successfully, so assign them to the output
// parameter.
options_copy.swap(local_options);
}
bool Option::delOption(uint16_t opt_type) {
auto const& x = options_.find(opt_type);
if (x != options_.end()) {
options_.erase(x);
return (true); // delete successful
}
return (false); // option not found, can't delete
}
std::string Option::toText(int indent) const {
std::stringstream output;
output << headerToText(indent) << ": ";
for (unsigned int i = 0; i < data_.size(); i++) {
if (i) {
output << ":";
}
output << setfill('0') << setw(2) << hex
<< static_cast<unsigned short>(data_[i]);
}
// Append suboptions.
output << suboptionsToText(indent + 2);
return (output.str());
}
std::string
Option::toString() const {
/// @todo: Implement actual conversion in derived classes.
return (toText(0));
}
std::vector<uint8_t>
Option::toBinary(const bool include_header) const {
OutputBuffer buf(len());
try {
// The RFC3396 adds support for long options split over multiple options
// using the same code.
pack(buf, false);
} catch (const std::exception &ex) {
isc_throw(OutOfRange, "unable to obtain hexadecimal representation"
" of option " << getType() << ": " << ex.what());
}
const uint8_t* option_data = static_cast<const uint8_t*>(buf.getData());
// Assign option data to a vector, with or without option header depending
// on the value of "include_header" flag.
std::vector<uint8_t> option_vec(option_data + (include_header ? 0 : getHeaderLen()),
option_data + buf.getLength());
return (option_vec);
}
std::string
Option::toHexString(const bool include_header) const {
// Prepare binary version of the option.
std::vector<uint8_t> option_vec = toBinary(include_header);
// Return hexadecimal representation prepended with 0x or empty string
// if option has no payload and the header fields are excluded.
std::ostringstream s;
if (!option_vec.empty()) {
s << "0x" << encode::encodeHex(option_vec);
}
return (s.str());
}
std::string
Option::headerToText(const int indent, const std::string& type_name) const {
std::stringstream output;
for (int i = 0; i < indent; i++)
output << " ";
int field_len = (getUniverse() == V4 ? 3 : 5);
output << "type=" << std::setw(field_len) << std::setfill('0')
<< type_;
if (!type_name.empty()) {
output << "(" << type_name << ")";
}
output << ", len=" << std::setw(field_len) << std::setfill('0')
<< len() - getHeaderLen();
return (output.str());
}
std::string
Option::suboptionsToText(const int indent) const {
std::stringstream output;
if (!options_.empty()) {
output << "," << std::endl << "options:";
for (auto const& opt : options_) {
output << std::endl << opt.second->toText(indent);
}
}
return (output.str());
}
uint16_t
Option::getHeaderLen() const {
switch (universe_) {
case V4:
return OPTION4_HDR_LEN; // header length for v4
case V6:
return OPTION6_HDR_LEN; // header length for v6
}
return 0; // should not happen
}
void Option::addOption(OptionPtr opt) {
if (this == opt.get()) {
// Do not allow options to be added to themselves as this
// can lead to infinite recursion.
isc_throw(InvalidOperation, "option cannot be added to itself: " << toText());
}
options_.insert(make_pair(opt->getType(), opt));
}
uint8_t Option::getUint8() const {
if (data_.size() < sizeof(uint8_t) ) {
isc_throw(OutOfRange, "Attempt to read uint8 from option " << type_
<< " that has size " << data_.size());
}
return (data_[0]);
}
uint16_t Option::getUint16() const {
// readUint16() checks and throws OutOfRange if data_ is too small.
return (readUint16(&data_[0], data_.size()));
}
uint32_t Option::getUint32() const {
// readUint32() checks and throws OutOfRange if data_ is too small.
return (readUint32(&data_[0], data_.size()));
}
void Option::setUint8(uint8_t value) {
data_.resize(sizeof(value));
data_[0] = value;
}
void Option::setUint16(uint16_t value) {
data_.resize(sizeof(value));
writeUint16(value, &data_[0], data_.size());
}
void Option::setUint32(uint32_t value) {
data_.resize(sizeof(value));
writeUint32(value, &data_[0], data_.size());
}
bool Option::equals(const OptionPtr& other) const {
return (equals(*other));
}
bool Option::equals(const Option& other) const {
return ((getType() == other.getType()) &&
(getData() == other.getData()));
}
Option::~Option() {
}
bool Option::lenient_parsing_;
} // end of isc::dhcp namespace
} // end of isc namespace
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