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Diffstat (limited to 'contrib/epee/src/http_auth.cpp')
| -rw-r--r-- | contrib/epee/src/http_auth.cpp | 527 |
1 files changed, 527 insertions, 0 deletions
diff --git a/contrib/epee/src/http_auth.cpp b/contrib/epee/src/http_auth.cpp new file mode 100644 index 000000000..98870a7a9 --- /dev/null +++ b/contrib/epee/src/http_auth.cpp @@ -0,0 +1,527 @@ +// Copyright (c) 2014-2016, The Monero Project +// +// All rights reserved. +// +// Redistribution and use in source and binary forms, with or without modification, are +// permitted provided that the following conditions are met: +// +// 1. Redistributions of source code must retain the above copyright notice, this list of +// conditions and the following disclaimer. +// +// 2. Redistributions in binary form must reproduce the above copyright notice, this list +// of conditions and the following disclaimer in the documentation and/or other +// materials provided with the distribution. +// +// 3. Neither the name of the copyright holder nor the names of its contributors may be +// used to endorse or promote products derived from this software without specific +// prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY +// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF +// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL +// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, +// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS +// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, +// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF +// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +#include "net/http_auth.h" + +#include <array> +#include <boost/algorithm/string/predicate.hpp> +#include <boost/fusion/adapted/std_tuple.hpp> +#include <boost/fusion/algorithm/iteration/for_each.hpp> +#include <boost/fusion/algorithm/query/any.hpp> +#include <boost/range/algorithm/copy.hpp> +#include <boost/range/algorithm/find_if.hpp> +#include <boost/range/iterator_range_core.hpp> +#include <boost/range/join.hpp> +#include <boost/spirit/include/qi_alternative.hpp> +#include <boost/spirit/include/qi_and_predicate.hpp> +#include <boost/spirit/include/qi_char.hpp> +#include <boost/spirit/include/qi_char_class.hpp> +#include <boost/spirit/include/qi_difference.hpp> +#include <boost/spirit/include/qi_kleene.hpp> +#include <boost/spirit/include/qi_optional.hpp> +#include <boost/spirit/include/qi_parse.hpp> +#include <boost/spirit/include/qi_plus.hpp> +#include <boost/spirit/include/qi_no_case.hpp> +#include <boost/spirit/include/qi_raw.hpp> +#include <boost/spirit/include/qi_rule.hpp> +#include <boost/spirit/include/qi_sequence.hpp> +#include <boost/spirit/include/qi_string.hpp> +#include <boost/spirit/include/qi_symbols.hpp> +#include <boost/spirit/include/qi_uint.hpp> +#include <boost/utility/string_ref.hpp> +#include <cassert> +#include <functional> +#include <iterator> +#include <tuple> +#include <type_traits> + +#include "crypto/crypto.h" +#include "md5_l.h" +#include "string_coding.h" + +/* This file uses the `u8` prefix and specifies all chars by ASCII numeric +value. This is for maximum portability - C++ does not actually specify ASCII +as the encoding type for unprefixed string literals, etc. Although rare, the +effort required to support rare compiler encoding types is low. + +Also be careful of qi::ascii character classes (`qi::asci::alpha`, etc.) - +non-ASCII characters will cause undefined behavior in the table lookup until +boost 1.60. The expression `&qi::ascii::char_` will fail on non-ASCII +characters without "consuming" the input character. */ + +namespace +{ + // string_ref is only constexpr if length is given + template<std::size_t N> + constexpr boost::string_ref ceref(const char (&arg)[N]) + { + return boost::string_ref(arg, N - 1); + } + + constexpr const auto auth_realm = ceref(u8"monero-wallet-rpc"); + constexpr const char comma = 44; + constexpr const char equal_sign = 61; + constexpr const char quote = 34; + constexpr const auto sess_algo = ceref(u8"-sess"); + + //// Digest Algorithms + + template<std::size_t N> + std::array<char, N * 2> to_hex(const std::array<std::uint8_t, N>& digest) noexcept + { + static constexpr const char alphabet[] = u8"0123456789abcdef"; + static_assert(sizeof(alphabet) == 17, "bad alphabet size"); + + // TODO upgrade (improve performance) of to hex in epee string tools + std::array<char, N * 2> out{{}}; + auto current = out.begin(); + for (const std::uint8_t byte : digest) + { + *current = alphabet[byte >> 4]; + ++current; + *current = alphabet[byte & 0x0F]; + ++current; + } + return out; + } + + struct md5_ + { + static constexpr const boost::string_ref name = ceref(u8"MD5"); + + struct update + { + template<typename T> + void operator()(const T& arg) const + { + const boost::iterator_range<const char*> data(boost::as_literal(arg)); + md5::MD5Update( + std::addressof(ctx), + reinterpret_cast<const std::uint8_t*>(data.begin()), + data.size() + ); + } + void operator()(const std::string& arg) const + { + (*this)(boost::string_ref(arg)); + } + + md5::MD5_CTX& ctx; + }; + + template<typename... T> + std::array<char, 32> operator()(const T&... args) const + { + md5::MD5_CTX ctx{}; + md5::MD5Init(std::addressof(ctx)); + boost::fusion::for_each(std::tie(args...), update{ctx}); + + std::array<std::uint8_t, 16> digest{{}}; + md5::MD5Final(digest.data(), std::addressof(ctx)); + return to_hex(digest); + } + }; + constexpr const boost::string_ref md5_::name; + + //! Digest Algorithms available for HTTP Digest Auth. + constexpr const std::tuple<md5_> digest_algorithms{}; + + //// Various String Parsing Utilities + + struct ascii_tolower_ + { + template<typename Char> + Char operator()(Char value) const noexcept + { + static_assert(std::is_integral<Char>::value, "only integral types supported"); + return (65 <= value && value <= 90) ? (value + 32) : value; + } + }; + constexpr const ascii_tolower_ ascii_tolower{}; + + struct ascii_iequal_ + { + template<typename Char> + bool operator()(Char left, Char right) const noexcept + { + return ascii_tolower(left) == ascii_tolower(right); + } + }; + constexpr const ascii_iequal_ ascii_iequal{}; + + //// Digest Authentication + + struct auth_request + { + using iterator = const char*; + enum status{ kFail = 0, kStale, kPass }; + + static status verify(const std::string& method, const std::string& request, + const epee::net_utils::http::http_auth::session& user) + { + struct parser + { + using field_parser = std::function<bool(const parser&, iterator&, iterator, auth_request&)>; + + explicit parser() : field_table(), skip_whitespace(), header(), token(), fields() { + using namespace std::placeholders; + namespace qi = boost::spirit::qi; + + struct parse_nc + { + bool operator()(const parser&, iterator& current, const iterator end, auth_request& result) const + { + return qi::parse( + current, end, + (qi::raw[qi::uint_parser<std::uint32_t, 16, 8, 8>{}]), + result.nc + ); + } + }; + struct parse_token + { + bool operator()(const parser& parse, iterator& current, const iterator end, + boost::iterator_range<iterator>& result) const + { + return qi::parse(current, end, parse.token, result); + } + }; + struct parse_string + { + bool operator()(const parser&, iterator& current, const iterator end, + boost::iterator_range<iterator>& result) const + { + return qi::parse( + current, end, + (qi::lit(quote) >> qi::raw[+(u8"\\\"" | (qi::ascii::char_ - quote))] >> qi::lit(quote)), + result + ); + } + }; + struct parse_response + { + bool operator()(const parser&, iterator& current, const iterator end, auth_request& result) const + { + using byte = qi::uint_parser<std::uint8_t, 16, 2, 2>; + return qi::parse( + current, end, + (qi::lit(quote) >> qi::raw[+(byte{})] >> qi::lit(quote)), + result.response + ); + } + }; + + field_table.add + (u8"algorithm", std::bind(parse_token{}, _1, _2, _3, std::bind(&auth_request::algorithm, _4))) + (u8"cnonce", std::bind(parse_string{}, _1, _2, _3, std::bind(&auth_request::cnonce, _4))) + (u8"nc", parse_nc{}) + (u8"nonce", std::bind(parse_string{}, _1, _2, _3, std::bind(&auth_request::nonce, _4))) + (u8"qop", std::bind(parse_token{}, _1, _2, _3, std::bind(&auth_request::qop, _4))) + (u8"realm", std::bind(parse_string{}, _1, _2, _3, std::bind(&auth_request::realm, _4))) + (u8"response", parse_response{}) + (u8"uri", std::bind(parse_string{}, _1, _2, _3, std::bind(&auth_request::uri, _4))) + (u8"username", std::bind(parse_string{}, _1, _2, _3, std::bind(&auth_request::username, _4))); + + skip_whitespace = *(&qi::ascii::char_ >> qi::ascii::space); + header = skip_whitespace >> qi::ascii::no_case[u8"digest"] >> skip_whitespace; + token = + -qi::lit(quote) >> + qi::raw[+(&qi::ascii::char_ >> (qi::ascii::graph - qi::ascii::char_(u8"()<>@,;:\\\"/[]?={}")))] >> + -qi::lit(quote); + fields = field_table >> skip_whitespace >> equal_sign >> skip_whitespace; + } + + boost::optional<auth_request> operator()(const std::string& method, const std::string& request) const + { + namespace qi = boost::spirit::qi; + + iterator current = request.data(); + const iterator end = current + request.size(); + + if (!qi::parse(current, end, header)) + { + return boost::none; + } + + auth_request info(method); + field_parser null_parser{}; + std::reference_wrapper<const field_parser> field = null_parser; + + do // require at least one field; require field after `,` character + { + if (!qi::parse(current, end, fields, field) || !field(*this, current, end, info)) + { + return boost::none; + } + qi::parse(current, end, skip_whitespace); + } while (qi::parse(current, end, qi::char_(comma) >> skip_whitespace)); + return boost::make_optional(current == end, info); + } + + private: + boost::spirit::qi::symbols< + char, field_parser, boost::spirit::qi::tst<char, field_parser>, ascii_tolower_ + > field_table; + boost::spirit::qi::rule<iterator> skip_whitespace; + boost::spirit::qi::rule<iterator> header; + boost::spirit::qi::rule<iterator, boost::iterator_range<iterator>()> token; + boost::spirit::qi::rule<iterator, std::reference_wrapper<const field_parser>()> fields; + }; // parser + + static const parser parse; + return do_verify(parse(method, request), user); + } + + private: + explicit auth_request(const std::string& method_) + : algorithm() + , cnonce() + , method(method_) + , nc() + , nonce() + , qop() + , realm() + , response() + , uri() + , username() { + } + + struct has_valid_response + { + template<typename Digest, typename Result> + Result generate_old_response(Digest digest, const Result& key, const Result& auth) const + { + return digest(key, u8":", request.nonce, u8":", auth); + } + + template<typename Digest, typename Result> + Result generate_new_response(Digest digest, const Result& key, const Result& auth) const + { + return digest( + key, u8":", request.nonce, u8":", request.nc, u8":", request.cnonce, u8":", request.qop, u8":", auth + ); + } + + template<typename Digest> + typename std::result_of<Digest()>::type generate_auth(Digest digest) const + { + return digest(request.method, u8":", request.uri); + } + + template<typename Result> + bool check(const Result& result) const + { + return boost::equals(request.response, result, ascii_iequal); + } + + template<typename Digest> + bool operator()(const Digest& digest) const + { + if (boost::starts_with(request.algorithm, Digest::name, ascii_iequal) || + (request.algorithm.empty() && std::is_same<md5_, Digest>::value)) + { + auto key = digest(user.credentials.username, u8":", auth_realm, u8":", user.credentials.password); + + if (boost::ends_with(request.algorithm, sess_algo, ascii_iequal)) + { + key = digest(key, u8":", request.nonce, u8":", request.cnonce); + } + + if (request.qop.empty()) + { + return check(generate_old_response(digest, std::move(key), generate_auth(digest))); + } + else if (boost::equals(ceref(u8"auth"), request.qop, ascii_iequal)) + { + return check(generate_new_response(digest, std::move(key), generate_auth(digest))); + } + } + return false; + } + + const auth_request& request; + const epee::net_utils::http::http_auth::session& user; + }; + + static status do_verify(const boost::optional<auth_request>& request, + const epee::net_utils::http::http_auth::session& user) + { + if (request && + boost::equals(request->username, user.credentials.username) && + boost::fusion::any(digest_algorithms, has_valid_response{*request, user})) + { + if (boost::equals(request->nonce, user.nonce)) + { + // RFC 2069 format does not verify nc value - allow just once + if (user.counter == 1 || (!request->qop.empty() && request->counter() == user.counter)) + { + return kPass; + } + } + return kStale; + } + return kFail; + } + + boost::optional<std::uint32_t> counter() const + { + namespace qi = boost::spirit::qi; + using hex = qi::uint_parser<std::uint32_t, 16>; + std::uint32_t value = 0; + const bool converted = qi::parse(nc.begin(), nc.end(), hex{}, value); + return boost::make_optional(converted, value); + } + + boost::iterator_range<iterator> algorithm; + boost::iterator_range<iterator> cnonce; + boost::string_ref method; + boost::iterator_range<iterator> nc; + boost::iterator_range<iterator> nonce; + boost::iterator_range<iterator> qop; + boost::iterator_range<iterator> realm; + boost::iterator_range<iterator> response; + boost::iterator_range<iterator> uri; + boost::iterator_range<iterator> username; + }; // auth_request + + struct add_challenge + { + template<typename T> + static void add_field(std::string& str, const char* const name, const T& value) + { + str.push_back(comma); + str.append(name); + str.push_back(equal_sign); + boost::range::copy(value, std::back_inserter(str)); + } + + template<typename T> + using quoted_result = boost::joined_range< + const boost::joined_range<const boost::string_ref, const T>, const boost::string_ref + >; + + template<typename T> + static quoted_result<T> quoted(const T& arg) + { + return boost::range::join(boost::range::join(ceref(u8"\""), arg), ceref(u8"\"")); + } + + template<typename Digest> + void operator()(const Digest& digest) const + { + static constexpr const auto fname = ceref(u8"WWW-authenticate"); + static constexpr const auto fvalue = ceref(u8"Digest qop=\"auth\""); + + for (unsigned i = 0; i < 2; ++i) + { + std::string out(fvalue); + + const auto algorithm = boost::range::join( + Digest::name, (i == 0 ? boost::string_ref{} : sess_algo) + ); + add_field(out, u8"algorithm", algorithm); + add_field(out, u8"realm", quoted(auth_realm)); + add_field(out, u8"nonce", quoted(nonce)); + add_field(out, u8"stale", is_stale ? ceref("true") : ceref("false")); + + fields.push_back(std::make_pair(std::string(fname), std::move(out))); + } + } + + const std::string& nonce; + std::list<std::pair<std::string, std::string>>& fields; + const bool is_stale; + }; + + epee::net_utils::http::http_response_info create_digest_response( + const std::string& nonce, const bool is_stale) + { + epee::net_utils::http::http_response_info rc{}; + rc.m_response_code = 401; + rc.m_response_comment = u8"Unauthorized"; + rc.m_mime_tipe = u8"text/html"; + rc.m_body = + u8"<html><head><title>Unauthorized Access</title></head><body><h1>401 Unauthorized</h1></body></html>"; + + boost::fusion::for_each( + digest_algorithms, add_challenge{nonce, rc.m_additional_fields, is_stale} + ); + + return rc; + } +} + +namespace epee +{ + namespace net_utils + { + namespace http + { + http_auth::http_auth(login credentials) + : user(session{std::move(credentials)}) { + } + + boost::optional<http_response_info> http_auth::process(const http_request_info& request) + { + assert(user); + using field = std::pair<std::string, std::string>; + + const std::list<field>& fields = request.m_header_info.m_etc_fields; + const auto auth = boost::find_if(fields, [] (const field& value) { + return boost::equals(ceref(u8"authorization"), value.first, ascii_iequal); + }); + + bool is_stale = false; + if (auth != fields.end()) + { + ++(user->counter); + switch (auth_request::verify(request.m_http_method_str, auth->second, *user)) + { + case auth_request::kPass: + return boost::none; + + case auth_request::kStale: + is_stale = true; + break; + + default: + case auth_request::kFail: + break; + } + } + user->counter = 0; + { + std::array<std::uint8_t, 16> rand_128bit{{}}; + crypto::rand(rand_128bit.size(), rand_128bit.data()); + user->nonce = string_encoding::base64_encode(rand_128bit.data(), rand_128bit.size()); + } + return create_digest_response(user->nonce, is_stale); + } + } + } +} + |