rrparamregistry.cc

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// Copyright (C) 2010-2015 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 <cassert>
#include <algorithm>
#include <cctype>
#include <functional>
#include <map>
#include <string>
#include <sstream>
#include <utility>

#include <stdint.h>

#include <boost/shared_ptr.hpp>

#include <exceptions/exceptions.h>

#include <dns/rrparamregistry.h>
#include <dns/rrclass.h>
#include <dns/rrtype.h>
#include <dns/rdata.h>
#include <dns/rdataclass.h>

using namespace std;

using namespace isc::util;
using namespace isc::dns::rdata;

namespace isc {
namespace dns {

namespace {
bool
CICharLess(char c1, char c2) {
    return (tolower(static_cast<unsigned char>(c1)) <
            tolower(static_cast<unsigned char>(c2)));
}

struct CIStringLess :
        public binary_function<string, string, bool>
{
    bool operator()(const string& s1, const string& s2) const
    {
        return (lexicographical_compare(s1.begin(), s1.end(),
                                        s2.begin(), s2.end(), CICharLess));
    }
};

struct RRTypeParam {
    RRTypeParam(const string& code_string, uint16_t code) :
        code_string_(code_string), code_(code) {}
    string code_string_;
    uint16_t code_;

    static const unsigned int MAX_CODE = 0xffff;
    static const string& UNKNOWN_PREFIX();
    static size_t UNKNOWN_PREFIXLEN();
    static const string& UNKNOWN_MAX();
    static size_t UNKNOWN_MAXLEN();
};

typedef boost::shared_ptr<RRTypeParam> RRTypeParamPtr;
typedef map<string, RRTypeParamPtr, CIStringLess> StrRRTypeMap;
typedef map<uint16_t, RRTypeParamPtr> CodeRRTypeMap;

inline const string&
RRTypeParam::UNKNOWN_PREFIX() {
    static const string p("TYPE");
    return (p);
}

inline size_t
RRTypeParam::UNKNOWN_PREFIXLEN() {
    static size_t plen = UNKNOWN_PREFIX().size();
    return (plen);
}

inline const string&
RRTypeParam::UNKNOWN_MAX() {
    static const string p("TYPE65535");
    return (p);
}

inline size_t
RRTypeParam::UNKNOWN_MAXLEN() {
    static size_t plen = UNKNOWN_MAX().size();
    return (plen);
}

struct RRClassParam {
    RRClassParam(const string& code_string, uint16_t code) :
        code_string_(code_string), code_(code) {}
    string code_string_;
    uint16_t code_;

    static const unsigned int MAX_CODE = 0xffff;
    static const string& UNKNOWN_PREFIX();
    static size_t UNKNOWN_PREFIXLEN();
    static const string& UNKNOWN_MAX();
    static size_t UNKNOWN_MAXLEN();
};

typedef boost::shared_ptr<RRClassParam> RRClassParamPtr;
typedef map<string, RRClassParamPtr, CIStringLess> StrRRClassMap;
typedef map<uint16_t, RRClassParamPtr> CodeRRClassMap;

inline const string&
RRClassParam::UNKNOWN_PREFIX() {
    static const string p("CLASS");
    return (p);
}

inline size_t
RRClassParam::UNKNOWN_PREFIXLEN() {
    static size_t plen = UNKNOWN_PREFIX().size();
    return (plen);
}

inline const string&
RRClassParam::UNKNOWN_MAX() {
    static const string p("CLASS65535");
    return (p);
}

inline size_t
RRClassParam::UNKNOWN_MAXLEN() {
    static size_t plen = UNKNOWN_MAX().size();
    return (plen);
}
} // end of anonymous namespace

typedef pair<RRType, RRClass> RRTypeClass;
typedef map<RRTypeClass, RdataFactoryPtr> RdataFactoryMap;
typedef map<RRType, RdataFactoryPtr> GenericRdataFactoryMap;

template <typename T>
class RdataFactory : public AbstractRdataFactory {
public:
    virtual RdataPtr create(const string& rdata_str) const
    {
        return (RdataPtr(new T(rdata_str)));
    }

    virtual RdataPtr create(InputBuffer& buffer, size_t rdata_len) const
    {
        return (RdataPtr(new T(buffer, rdata_len)));
    }

    virtual RdataPtr create(const Rdata& source) const
    {
        return (RdataPtr(new T(dynamic_cast<const T&>(source))));
    }

    virtual RdataPtr create(MasterLexer& lexer, const Name* origin,
                            MasterLoader::Options options,
                            MasterLoaderCallbacks& callbacks) const
    {
        return (RdataPtr(new T(lexer, origin, options, callbacks)));
    }
};

struct RRParamRegistryImpl {
    StrRRTypeMap str2typemap;
    CodeRRTypeMap code2typemap;
    StrRRClassMap str2classmap;
    CodeRRClassMap code2classmap;
    RdataFactoryMap rdata_factories;
    GenericRdataFactoryMap genericrdata_factories;
};

RRParamRegistry::RRParamRegistry() {
    impl_ = new RRParamRegistryImpl;

    // set up parameters for well-known RRs
    try {
        // BEGIN_WELL_KNOWN_PARAMS
        add("A", 1, "IN", 1, RdataFactoryPtr(new RdataFactory<in::A>()));
        add("NS", 2, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::NS>()));
        add("CNAME", 5, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::CNAME>()));
        add("SOA", 6, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::SOA>()));
        add("PTR", 12, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::PTR>()));
        add("HINFO", 13, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::HINFO>()));
        add("MINFO", 14, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::MINFO>()));
        add("MX", 15, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::MX>()));
        add("TXT", 16, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::TXT>()));
        add("RP", 17, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::RP>()));
        add("AFSDB", 18, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::AFSDB>()));
        add("AAAA", 28, "IN", 1, RdataFactoryPtr(new RdataFactory<in::AAAA>()));
        add("SRV", 33, "IN", 1, RdataFactoryPtr(new RdataFactory<in::SRV>()));
        add("NAPTR", 35, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::NAPTR>()));
        add("DNAME", 39, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::DNAME>()));
        add("OPT", 41, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::OPT>()));
        add("DS", 43, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::DS>()));
        add("SSHFP", 44, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::SSHFP>()));
        add("RRSIG", 46, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::RRSIG>()));
        add("NSEC", 47, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::NSEC>()));
        add("DNSKEY", 48, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::DNSKEY>()));
        add("DHCID", 49, "IN", 1, RdataFactoryPtr(new RdataFactory<in::DHCID>()));
        add("NSEC3", 50, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::NSEC3>()));
        add("NSEC3PARAM", 51, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::NSEC3PARAM>()));
        add("TLSA", 52, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::TLSA>()));
        add("SPF", 99, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::SPF>()));
        add("CAA", 257, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::CAA>()));
        add("DLV", 32769, "IN", 1, RdataFactoryPtr(new RdataFactory<generic::DLV>()));
        add("A", 1, "CH", 3, RdataFactoryPtr(new RdataFactory<ch::A>()));
        add("A", 1, "HS", 4, RdataFactoryPtr(new RdataFactory<hs::A>()));
        add("TSIG", 250, "ANY", 255, RdataFactoryPtr(new RdataFactory<any::TSIG>()));
        add("NS", 2, RdataFactoryPtr(new RdataFactory<generic::NS>()));
        add("CNAME", 5, RdataFactoryPtr(new RdataFactory<generic::CNAME>()));
        add("SOA", 6, RdataFactoryPtr(new RdataFactory<generic::SOA>()));
        add("PTR", 12, RdataFactoryPtr(new RdataFactory<generic::PTR>()));
        add("HINFO", 13, RdataFactoryPtr(new RdataFactory<generic::HINFO>()));
        add("MINFO", 14, RdataFactoryPtr(new RdataFactory<generic::MINFO>()));
        add("MX", 15, RdataFactoryPtr(new RdataFactory<generic::MX>()));
        add("TXT", 16, RdataFactoryPtr(new RdataFactory<generic::TXT>()));
        add("RP", 17, RdataFactoryPtr(new RdataFactory<generic::RP>()));
        add("AFSDB", 18, RdataFactoryPtr(new RdataFactory<generic::AFSDB>()));
        add("NAPTR", 35, RdataFactoryPtr(new RdataFactory<generic::NAPTR>()));
        add("DNAME", 39, RdataFactoryPtr(new RdataFactory<generic::DNAME>()));
        add("OPT", 41, RdataFactoryPtr(new RdataFactory<generic::OPT>()));
        add("DS", 43, RdataFactoryPtr(new RdataFactory<generic::DS>()));
        add("SSHFP", 44, RdataFactoryPtr(new RdataFactory<generic::SSHFP>()));
        add("RRSIG", 46, RdataFactoryPtr(new RdataFactory<generic::RRSIG>()));
        add("NSEC", 47, RdataFactoryPtr(new RdataFactory<generic::NSEC>()));
        add("DNSKEY", 48, RdataFactoryPtr(new RdataFactory<generic::DNSKEY>()));
        add("NSEC3", 50, RdataFactoryPtr(new RdataFactory<generic::NSEC3>()));
        add("NSEC3PARAM", 51, RdataFactoryPtr(new RdataFactory<generic::NSEC3PARAM>()));
        add("TLSA", 52, RdataFactoryPtr(new RdataFactory<generic::TLSA>()));
        add("SPF", 99, RdataFactoryPtr(new RdataFactory<generic::SPF>()));
        add("CAA", 257, RdataFactoryPtr(new RdataFactory<generic::CAA>()));
        add("DLV", 32769, RdataFactoryPtr(new RdataFactory<generic::DLV>()));
        // Meta and non-implemented RR types
        addType("IPSECKEY", 45);
        addType("L32", 105);
        addType("NID", 104);
        addType("LP", 107);
        addType("L64", 106);
        addType("KX", 36);
        addType("UNSPEC", 103);
        addType("MAILA", 254);
        addType("MAILB", 253);
        addType("HIP", 55);
        addType("LOC", 29);
        addType("URI", 256);
        addType("APL", 42);
        addType("GPOS", 27);
        addType("TKEY", 249);
        addType("MG", 8);
        addType("MR", 9);
        addType("IXFR", 251);
        addType("MB", 7);
        addType("MF", 4);
        addType("AXFR", 252);
        addType("ANY", 255);
        addType("MD", 3);
        addType("CERT", 37);
        addType("KEY", 25);
        addType("SIG", 24);
        addType("A6", 38);
        addType("PX", 26);
        addType("RT", 21);
        addType("X25", 19);
        addType("NSAP-PTR", 23);
        addType("NSAP", 22);
        addType("NXT", 30);
        addType("NULL", 10);
        addType("WKS", 11);
        addType("ISDN", 20);
        // Meta classes
        addClass("NONE", 254);
        // END_WELL_KNOWN_PARAMS
    } catch (...) {
        delete impl_;
        throw;
    }
}

RRParamRegistry::~RRParamRegistry() {
    delete impl_;
}

RRParamRegistry&
RRParamRegistry::getRegistry() {
    static RRParamRegistry registry;

    return (registry);
}

void
RRParamRegistry::add(const std::string& typecode_string, uint16_t typecode,
                     RdataFactoryPtr rdata_factory)
{
    bool type_added = false;
    try {
        type_added = addType(typecode_string, typecode);
        impl_->genericrdata_factories.insert(pair<RRType, RdataFactoryPtr>(
                                                 RRType(typecode),
                                                 rdata_factory));
    } catch (...) {
        if (type_added) {
            removeType(typecode);
        }
        throw;
    }
}

void
RRParamRegistry::add(const std::string& typecode_string, uint16_t typecode,
                     const std::string& classcode_string, uint16_t classcode,
                     RdataFactoryPtr rdata_factory)
{
    // Rollback logic on failure is complicated.  If adding the new type or
    // class fails, we should revert to the original state, cleaning up
    // intermediate state.  But we need to make sure that we don't remove
    // existing data.  addType()/addClass() will simply ignore an attempt to
    // add the same data, so the cleanup should be performed only when we add
    // something new but we fail in other part of the process.
    bool type_added = false;
    bool class_added = false;

    try {
        type_added = addType(typecode_string, typecode);
        class_added = addClass(classcode_string, classcode);
        impl_->rdata_factories.insert(pair<RRTypeClass, RdataFactoryPtr>(
                                          RRTypeClass(RRType(typecode),
                                                      RRClass(classcode)),
                                          rdata_factory));
    } catch (...) {
        if (type_added) {
            removeType(typecode);
        }
        if (class_added) {
            removeClass(classcode);
        }
        throw;
    }
}

bool
RRParamRegistry::removeRdataFactory(const RRType& rrtype,
                                    const RRClass& rrclass)
{
    RdataFactoryMap::iterator found =
        impl_->rdata_factories.find(RRTypeClass(rrtype, rrclass));
    if (found != impl_->rdata_factories.end()) {
        impl_->rdata_factories.erase(found);
        return (true);
    }

    return (false);
}

bool
RRParamRegistry::removeRdataFactory(const RRType& rrtype) {
    GenericRdataFactoryMap::iterator found =
        impl_->genericrdata_factories.find(rrtype);
    if (found != impl_->genericrdata_factories.end()) {
        impl_->genericrdata_factories.erase(found);
        return (true);
    }

    return (false);
}

namespace {
bool CICharEqual(char c1, char c2) {
    return (tolower(static_cast<unsigned char>(c1)) ==
            tolower(static_cast<unsigned char>(c2)));
}

bool
caseStringEqual(const string& s1, const string& s2, size_t n) {
    assert(s1.size() >= n && s2.size() >= n);

    return (mismatch(s1.begin(), s1.begin() + n, s2.begin(), CICharEqual).first
            == s1.begin() + n);
}

template <typename PT, typename MC, typename MS, typename ET>
inline bool
addParam(const string& code_string, uint16_t code, MC& codemap, MS& stringmap)
{
    // Duplicate type check
    typename MC::const_iterator found = codemap.find(code);
    if (found != codemap.end()) {
        if (found->second->code_string_ != code_string) {
            isc_throw(ET, "Duplicate RR parameter registration");
        }
        return (false);
    }

    typedef boost::shared_ptr<PT> ParamPtr;
    typedef pair<string, ParamPtr> StrParamPair;
    typedef pair<uint16_t, ParamPtr> CodeParamPair;
    ParamPtr param = ParamPtr(new PT(code_string, code));
    try {
        stringmap.insert(StrParamPair(code_string, param));
        codemap.insert(CodeParamPair(code, param));
    } catch (...) {
        // Rollback to the previous state: not all of the erase operations will
        // find the entry, but we don't care.
        stringmap.erase(code_string);
        codemap.erase(code);
        throw;
    }

    return (true);
}

template <typename MC, typename MS>
inline bool
removeParam(uint16_t code, MC& codemap, MS& stringmap) {
    typename MC::iterator found = codemap.find(code);

    if (found != codemap.end()) {
        size_t erased = stringmap.erase(found->second->code_string_);
        // We must have a corresponding entry of the str2 map exists
        assert(erased == 1);

        codemap.erase(found);

        return (true);
    }

    return (false);
}

template <typename PT, typename MS>
inline bool
textToCode(const string& code_str, MS& stringmap, uint16_t& ret_code) {
    typename MS::const_iterator found;

    found = stringmap.find(code_str);
    if (found != stringmap.end()) {
        ret_code = found->second->code_;
        return (true);
    }

    size_t l = code_str.size();
    if (l > PT::UNKNOWN_PREFIXLEN() &&
        l <= PT::UNKNOWN_MAXLEN() &&
        caseStringEqual(code_str, PT::UNKNOWN_PREFIX(),
                        PT::UNKNOWN_PREFIXLEN())) {
        unsigned int code;
        istringstream iss(code_str.substr(PT::UNKNOWN_PREFIXLEN(),
                                          l - PT::UNKNOWN_PREFIXLEN()));
        iss >> dec >> code;
        if (iss.rdstate() == ios::eofbit && code <= PT::MAX_CODE) {
            ret_code = code;
            return (true);
        }
    }

    return (false);
}

template <typename PT, typename MC>
inline string
codeToText(uint16_t code, MC& codemap) {
    typename MC::const_iterator found;

    found = codemap.find(code);
    if (found != codemap.end()) {
        return (found->second->code_string_);
    }

    ostringstream ss;
    ss << code;
    return (PT::UNKNOWN_PREFIX() + ss.str());
}
}

bool
RRParamRegistry::addType(const string& type_string, uint16_t code) {
    return (addParam<RRTypeParam, CodeRRTypeMap, StrRRTypeMap, RRTypeExists>
            (type_string, code, impl_->code2typemap, impl_->str2typemap));
}

bool
RRParamRegistry::removeType(uint16_t code) {
    return (removeParam<CodeRRTypeMap, StrRRTypeMap>(code, impl_->code2typemap,
                                                     impl_->str2typemap));
}

bool
RRParamRegistry::textToTypeCode(const string& type_string,
                                uint16_t& type_code) const
{
    return (textToCode<RRTypeParam, StrRRTypeMap>
            (type_string, impl_->str2typemap, type_code));
}

string
RRParamRegistry::codeToTypeText(uint16_t code) const {
    return (codeToText<RRTypeParam, CodeRRTypeMap>(code, impl_->code2typemap));
}

bool
RRParamRegistry::addClass(const string& class_string, uint16_t code) {
    return (addParam<RRClassParam, CodeRRClassMap, StrRRClassMap, RRClassExists>
            (class_string, code, impl_->code2classmap, impl_->str2classmap));
}

bool
RRParamRegistry::removeClass(uint16_t code) {
    return (removeParam<CodeRRClassMap, StrRRClassMap>(code,
                                                       impl_->code2classmap,
                                                       impl_->str2classmap));
}

bool
RRParamRegistry::textToClassCode(const string& class_string,
                                 uint16_t& class_code) const
{
    return (textToCode<RRClassParam, StrRRClassMap>
            (class_string, impl_->str2classmap, class_code));
}

string
RRParamRegistry::codeToClassText(uint16_t code) const {
    return (codeToText<RRClassParam, CodeRRClassMap>(code,
                                                     impl_->code2classmap));
}

namespace {
inline const AbstractRdataFactory*
findRdataFactory(RRParamRegistryImpl* reg_impl,
                 const RRType& rrtype, const RRClass& rrclass)
{
    RdataFactoryMap::const_iterator found;
    found = reg_impl->rdata_factories.find(RRTypeClass(rrtype, rrclass));
    if (found != reg_impl->rdata_factories.end()) {
        return (found->second.get());
    }

    GenericRdataFactoryMap::const_iterator genfound =
        reg_impl->genericrdata_factories.find(rrtype);
    if (genfound != reg_impl->genericrdata_factories.end()) {
        return (genfound->second.get());
    }

    return (NULL);
}
}

RdataPtr
RRParamRegistry::createRdata(const RRType& rrtype, const RRClass& rrclass,
                             const std::string& rdata_string)
{
    // If the text indicates that it's rdata of an "unknown" type (beginning
    // with '\# n'), parse it that way. (TBD)

    const AbstractRdataFactory* factory =
        findRdataFactory(impl_, rrtype, rrclass);
    if (factory != NULL) {
        return (factory->create(rdata_string));
    }

    return (RdataPtr(new generic::Generic(rdata_string)));
}

RdataPtr
RRParamRegistry::createRdata(const RRType& rrtype, const RRClass& rrclass,
                             InputBuffer& buffer, size_t rdata_len)
{
    const AbstractRdataFactory* factory =
        findRdataFactory(impl_, rrtype, rrclass);
    if (factory != NULL) {
        return (factory->create(buffer, rdata_len));
    }

    return (RdataPtr(new generic::Generic(buffer, rdata_len)));
}

RdataPtr
RRParamRegistry::createRdata(const RRType& rrtype, const RRClass& rrclass,
                             const Rdata& source)
{
    const AbstractRdataFactory* factory =
        findRdataFactory(impl_, rrtype, rrclass);
    if (factory != NULL) {
        return (factory->create(source));
    }

    return (RdataPtr(new rdata::generic::Generic(
                         dynamic_cast<const generic::Generic&>(source))));
}

RdataPtr
RRParamRegistry::createRdata(const RRType& rrtype, const RRClass& rrclass,
                             MasterLexer& lexer, const Name* name,
                             MasterLoader::Options options,
                             MasterLoaderCallbacks& callbacks)
{
    const AbstractRdataFactory* factory =
        findRdataFactory(impl_, rrtype, rrclass);
    if (factory != NULL) {
        return (factory->create(lexer, name, options, callbacks));
    }

    return (RdataPtr(new generic::Generic(lexer, name, options, callbacks)));
}
}
}