diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/lib/dhcp/option4_dnr.cc | 184 | ||||
| -rw-r--r-- | src/lib/dhcp/option4_dnr.h | 25 |
2 files changed, 185 insertions, 24 deletions
diff --git a/src/lib/dhcp/option4_dnr.cc b/src/lib/dhcp/option4_dnr.cc index c07f708df0..0976152481 100644 --- a/src/lib/dhcp/option4_dnr.cc +++ b/src/lib/dhcp/option4_dnr.cc @@ -156,18 +156,19 @@ Option4Dnr::parseConfigData(const std::string& config_txt) { const std::unordered_set<std::string> DnrInstance::FORBIDDEN_SVC_PARAMS = {"ipv4hint", "ipv6hint"}; -const std::map<std::string, uint16_t> DnrInstance::SVC_PARAMS = { - {"mandatory", 0}, // RFC 9460, Section 14.3.2, not used in DNR - {"alpn", 1}, // RFC 9460, Section 14.3.2, mandatory in DNR - {"no-default-alpn", 2}, // RFC 9460, Section 14.3.2, not used in DNR - {"port", 3}, // RFC 9460, Section 14.3.2, optional in DNR - {"ipv4hint", 4}, // RFC 9460, Section 14.3.2, forbidden in DNR - {"ech", 5}, // RFC 9460, Section 14.3.2, not used in DNR - {"ipv6hint", 6}, // RFC 9460, Section 14.3.2, forbidden in DNR - {"dohpath", 7}, // RFC 9461, optional in DNR - {"ohttp", 8} // https://datatracker.ietf.org/doc/draft-ietf-ohai-svcb-config, - // not used in DNR -}; +const DnrInstance::SvcParamsMap DnrInstance::SVC_PARAMS = + boost::assign::list_of<DnrInstance::SvcParamsMap::relation> + ("mandatory", 0) // RFC 9460, Section 14.3.2, not used in DNR + ("alpn", 1) // RFC 9460, Section 14.3.2, mandatory in DNR + ("no-default-alpn", 2) // RFC 9460, Section 14.3.2, not used in DNR + ("port", 3) // RFC 9460, Section 14.3.2, optional in DNR + ("ipv4hint", 4) // RFC 9460, Section 14.3.2, forbidden in DNR + ("ech", 5) // RFC 9460, Section 14.3.2, not used in DNR + ("ipv6hint", 6) // RFC 9460, Section 14.3.2, forbidden in DNR + ("dohpath", 7) // RFC 9461, optional in DNR + ("ohttp", 8) // https://datatracker.ietf.org/doc/draft-ietf-ohai-svcb-config, + // not used in DNR + ; const std::set<uint8_t> DnrInstance::SUPPORTED_SVC_PARAMS = {1, 3, 7}; @@ -459,6 +460,58 @@ DnrInstance::checkFields() { } std::string +DnrInstance::svcParamValAsText(const std::pair<uint16_t, OpaqueDataTuple>& svc_param) const { + OptionBufferConstIter alpn_begin; + OptionBufferConstIter alpn_end; + std::ostringstream stream; + OpaqueDataTuple alpn_id_tuple(OpaqueDataTuple::LENGTH_1_BYTE); + bool first = true; + std::string ret; + + switch (svc_param.first) { + case 1: + // alpn + // read all protocols and concatenate them with comma + alpn_begin = svc_param.second.getData().begin(); + alpn_end = svc_param.second.getData().end(); + while (alpn_begin != alpn_end) { + try { + alpn_id_tuple.unpack(alpn_begin, alpn_end); + } catch (const Exception& e) { + isc_throw(BadValue, getLogPrefix() + << "Exception happened when tried to parse ALPN IDs" + << ". Error: " << e.what()); + } + + if (first) { + first = false; + } else { + stream << ","; + } + + stream << alpn_id_tuple.getText(); + alpn_begin += alpn_id_tuple.getTotalLength(); + } + + ret = stream.str(); + break; + case 3: + // port + // read uint16 from data buffer and return as string + ret = std::to_string( + readUint16(svc_param.second.getData().data(), svc_param.second.getLength())); + break; + case 7: + // dohpath + // convertion not needed, let's return data as string + ret = svc_param.second.getText(); + break; + } + + return (ret); +} + +std::string DnrInstance::getDnrInstanceAsText() const { std::ostringstream stream; stream << "service_priority=" << service_priority_ << ", adn_length=" << adn_length_ << ", " @@ -470,7 +523,20 @@ DnrInstance::getDnrInstanceAsText() const { } if (svc_params_length_ > 0) { - stream << ", svc_params='" + svc_params_ + "'"; + stream << ", svc_params='"; + bool first = true; + for (auto const& it : svc_params_map_) { + auto const& k = SVC_PARAMS.right.at(it.first); + if (first) { + first = false; + } else { + stream << " "; + } + + stream << k << "=" << svcParamValAsText(it); + } + + stream << "'"; } } @@ -552,11 +618,91 @@ void DnrInstance::unpackSvcParams(OptionBufferConstIter& begin, OptionBufferConstIter end) { svc_params_length_ = std::distance(begin, end); if (svc_params_length_ > 0) { - // This is used only when upacking hex bin option data. - // We only assign the data to svc_params_buf_ buffer. - // We do exact SvcParam syntax check when unpacking convenient option config notation - // in parseDnrInstanceConfigData(). svc_params_buf_.assign(begin, end); + + // used to check correct order of SvcParams + int prev_svc_param_key = -1; + + // When the list of SvcParams is non-empty, it contains a series of + // SvcParamKey=SvcParamValue pairs, represented as: + // - a 2-octet field containing the SvcParamKey as an integer in network byte order. + // - a 2-octet field containing the length of the SvcParamValue as an integer + // between 0 and 65535 in network byte order. (uint16) + // - an octet string of this length whose contents are the SvcParamValue in a format + // determined by the SvcParamKey. + while (begin != end) { + // Minimum SvcParams len shall be 4: + // 2 octets SvcParamKey + 2 octets SvcParamValue Len + if (std::distance(begin, end) < 4) { + isc_throw(OutOfRange, getLogPrefix() << "DNR SvcParams data truncated to size " + << std::distance(begin, end)); + } + + uint16_t num_svc_param_key = readUint16(&*begin, 2); + begin += 2; + + // Check if SvcParamKey is known in + // https://www.iana.org/assignments/dns-svcb/dns-svcb.xhtml + auto it = SVC_PARAMS.right.find(num_svc_param_key); + if (it == SVC_PARAMS.right.end()) { + isc_throw(InvalidOptionDnrSvcParams, + getLogPrefix() << "Wrong Svc Params syntax - key " << num_svc_param_key + << " not found in SvcParamKeys registry"); + } + + std::string svc_param_key = it->second; + + // As per RFC9463 Section 3.1.8: + // The service parameters do not include "ipv4hint" or "ipv6hint" parameters. + if (FORBIDDEN_SVC_PARAMS.find(svc_param_key) != FORBIDDEN_SVC_PARAMS.end()) { + isc_throw(InvalidOptionDnrSvcParams, getLogPrefix() + << "Wrong Svc Params syntax - key " + << svc_param_key << " must not be used"); + } + + // Check if SvcParamKey usage is supported by DNR DHCP option. + // Note that SUPPORTED_SVC_PARAMS set may expand in future. + if (SUPPORTED_SVC_PARAMS.find(num_svc_param_key) == SUPPORTED_SVC_PARAMS.end()) { + isc_throw(InvalidOptionDnrSvcParams, + getLogPrefix() << "Wrong Svc Params syntax - key " << svc_param_key + << " not supported in DNR option SvcParams"); + } + + // As per RFC9460 Section 2.2: + // SvcParamKeys SHALL appear in increasing numeric order. (...) + // There are no duplicate SvcParamKeys. + // + // We check for duplicates here. + if (svc_params_map_.find(num_svc_param_key) != svc_params_map_.end()) { + isc_throw(InvalidOptionDnrSvcParams, getLogPrefix() + << "Wrong Svc Params syntax - key " + << svc_param_key << " is duplicated."); + } + + // And we check correct order here. + if (num_svc_param_key <= prev_svc_param_key) { + isc_throw(InvalidOptionDnrSvcParams, + getLogPrefix() << "Wrong Svc Params syntax - SvcParamKeys" + << " SHALL appear in increasing numeric order."); + } + + prev_svc_param_key = num_svc_param_key; + + // Let's try to unpack SvcParamVal into a tuple. + OpaqueDataTuple svc_param_tuple(OpaqueDataTuple::LENGTH_2_BYTES); + try { + svc_param_tuple.unpack(begin, end); + } catch (const Exception& e) { + isc_throw(InvalidOptionDnrSvcParams, + getLogPrefix() + << "Wrong Svc Params syntax - failed to unpack SvcParamVal for " + << "SvcParamKey " << svc_param_key << ". Error: " << e.what()); + } + + svc_params_map_.insert(std::make_pair(num_svc_param_key, svc_param_tuple)); + begin += svc_param_tuple.getTotalLength(); + } + begin += svc_params_length_; } } @@ -694,8 +840,8 @@ DnrInstance::parseDnrInstanceConfigData(const std::string& config_txt) { // Check if SvcParamKey is known in // https://www.iana.org/assignments/dns-svcb/dns-svcb.xhtml - auto svc_params_iterator = SVC_PARAMS.find(svc_param_key); - if (svc_params_iterator == SVC_PARAMS.end()) { + auto svc_params_iterator = SVC_PARAMS.left.find(svc_param_key); + if (svc_params_iterator == SVC_PARAMS.left.end()) { isc_throw(InvalidOptionDnrSvcParams, getLogPrefix() << "Wrong Svc Params syntax - key " << svc_param_key << " not found in SvcParamKeys registry"); diff --git a/src/lib/dhcp/option4_dnr.h b/src/lib/dhcp/option4_dnr.h index 8afa80c0e5..682f68a710 100644 --- a/src/lib/dhcp/option4_dnr.h +++ b/src/lib/dhcp/option4_dnr.h @@ -8,6 +8,8 @@ #define OPTION4_DNR_H #include <asiolink/io_address.h> +#include <boost/assign.hpp> +#include <boost/bimap.hpp> #include <dhcp/dhcp4.h> #include <dhcp/dhcp6.h> #include <dhcp/option.h> @@ -57,6 +59,9 @@ public: /// @brief A Type defined for container holding IP addresses. typedef std::vector<isc::asiolink::IOAddress> AddressContainer; + /// @brief A Type defined for boost Bimap holding SvcParamKeys. + typedef boost::bimap<std::string, uint16_t> SvcParamsMap; + /// @brief Size in octets of Service Priority field. static const uint8_t SERVICE_PRIORITY_SIZE = 2; @@ -70,7 +75,7 @@ public: /// @brief Service parameters, used in DNR options in DHCPv4 and DHCPv6, but also in RA and DNS /// /// The IANA registry is maintained at https://www.iana.org/assignments/dns-svcb/dns-svcb.xhtml - static const std::map<std::string, uint16_t> SVC_PARAMS; + static const SvcParamsMap SVC_PARAMS; /// @brief Ordered set of supported SvcParamKeys. /// @@ -195,11 +200,11 @@ public: return (ip_addresses_); } - /// @brief Getter of the @c svc_params_ field. + /// @brief Returns a reference to the buffer holding SvcParam data. /// - /// @return Returns Service Parameters as a string. - const std::string& getSvcParams() const { - return (svc_params_); + /// @return a reference to the Service Parameters buffer + const OptionBuffer& getSvcParams() const { + return (svc_params_buf_); } /// @brief Returns minimal length of the DNR instance data (without headers) in octets. @@ -499,6 +504,16 @@ private: /// /// @note It must be called in all types of constructors of class @c DnrInstance . void initMembers(); + + /// @brief Returns string representation of SvcParamVal. + /// + /// @param svc_param a key-val pair from the @c svc_params_map_ map + /// + /// @return string representation of the SvcParamVal + /// + /// @throw BadValue thrown when there is a problem with reading alpn SvcParamVal from + /// @c svc_params_map_ + std::string svcParamValAsText(const std::pair<uint16_t, OpaqueDataTuple>& svc_param) const; }; /// @brief Represents DHCPv4 Encrypted DNS %Option (code 162). |