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Diffstat (limited to 'src/lib/dns/rrparamregistry-placeholder.cc')
| -rw-r--r-- | src/lib/dns/rrparamregistry-placeholder.cc | 556 |
1 files changed, 556 insertions, 0 deletions
diff --git a/src/lib/dns/rrparamregistry-placeholder.cc b/src/lib/dns/rrparamregistry-placeholder.cc new file mode 100644 index 0000000..4021460 --- /dev/null +++ b/src/lib/dns/rrparamregistry-placeholder.cc @@ -0,0 +1,556 @@ +// Copyright (C) 2010-2022 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 { +/// +/// The following function and class are a helper to define case-insensitive +/// equivalence relationship on strings. They are used in the mapping +/// containers below. +/// +bool +CICharLess(char c1, char c2) { + return (tolower(static_cast<unsigned char>(c1)) < + tolower(static_cast<unsigned char>(c2))); +} + +struct CIStringLess { + 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_; + + /// magic constants + 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_; + + /// magic constants + 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 + +/// Note: the element ordering in the type/class pair is intentional. +/// The standard library will perform inequality comparison (i.e, '<') +/// in the way that the second elements (RRClass) are compared only when +/// the first elements are equivalent. +/// In practice, when we compare two pairs of RRType and RRClass, RRClass +/// would be the same (and, in particular, be class IN) in the majority of +/// cases. So this comparison ordering should be more efficient in common +/// cases. +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))); + } +}; + +/// +/// \brief The \c RRParamRegistryImpl class is the actual implementation of +/// \c RRParamRegistry. +/// +/// The implementation is hidden from applications. We can refer to specific +/// members of this class only within the implementation source file. +/// +struct RRParamRegistryImpl { + /// Mappings from RR type codes to textual representations. + StrRRTypeMap str2typemap; + /// Mappings from textual representations of RR types to integer codes. + CodeRRTypeMap code2typemap; + /// Mappings from RR class codes to textual representations. + StrRRClassMap str2classmap; + /// Mappings from textual representations of RR classes to integer codes. + 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 + // 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 { +/// +/// These are helper functions to implement case-insensitive string comparison. +/// This could be simplified using strncasecmp(), but unfortunately it's not +/// included in <cstring>. To be as much as portable within the C++ standard +/// we take the "in house" approach here. +/// +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); +} + +/// Code logic for RRTypes and RRClasses is mostly common except (C++) type and +/// member names. So we define type-independent templates to describe the +/// common logic and let concrete classes use it to avoid code duplicates. +/// The following summarize template parameters used in the set of template +/// functions: +/// PT: parameter type, either RRTypeParam or RRClassParam +/// MC: type of mapping class from code: either CodeRRTypeMap or CodeRRClassMap +/// MS: type of mapping class from string: either StrRRTypeMap or StrRRClassMap +/// ET: exception type for error handling: either InvalidRRType or +/// InvalidRRClass +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))); +} +} +} |