Add server auth to monerod, and client auth to wallet-cli and wallet-rpc

1 files changed, 738 insertions, 0 deletions

diff --git a/tests/unit_tests/http.cpp b/tests/unit_tests/http.cpp
new file mode 100644
index 000000000..3513fa327
--- /dev/null
+++ b/tests/unit_tests/http.cpp
@@ -0,0 +1,738 @@
+// 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 "gtest/gtest.h"
+#include "net/http_auth.h"
+
+#include <boost/algorithm/string/predicate.hpp>
+#include <boost/fusion/adapted/std_pair.hpp>
+#include <boost/range/algorithm/find_if.hpp>
+#include <boost/range/iterator_range_core.hpp>
+#include <boost/spirit/include/karma_char.hpp>
+#include <boost/spirit/include/karma_list.hpp>
+#include <boost/spirit/include/karma_generate.hpp>
+#include <boost/spirit/include/karma_right_alignment.hpp>
+#include <boost/spirit/include/karma_sequence.hpp>
+#include <boost/spirit/include/karma_string.hpp>
+#include <boost/spirit/include/karma_uint.hpp>
+#include <boost/spirit/include/qi_alternative.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_eoi.hpp>
+#include <boost/spirit/include/qi_list.hpp>
+#include <boost/spirit/include/qi_parse.hpp>
+#include <boost/spirit/include/qi_plus.hpp>
+#include <boost/spirit/include/qi_sequence.hpp>
+#include <boost/spirit/include/qi_string.hpp>
+#include <cstdint>
+#include <iterator>
+#include <string>
+#include <unordered_map>
+#include <utility>
+#include <vector>
+
+#include "md5_l.h"
+#include "string_tools.h"
+
+namespace {
+namespace http = epee::net_utils::http;
+using fields = std::unordered_map<std::string, std::string>;
+using auth_responses = std::vector<fields>;
+
+std::string quoted(std::string str)
+{
+  str.insert(str.begin(), '"');
+  str.push_back('"');
+  return str;
+}
+
+void write_fields(std::string& out, const fields& args)
+{
+  namespace karma = boost::spirit::karma;
+  karma::generate(
+    std::back_inserter(out),
+    (karma::string << " = " << karma::string) % " , ", 
+    args);
+}
+
+std::string write_fields(const fields& args)
+{
+  std::string out{};
+  write_fields(out, args);
+  return out;
+}
+
+http::http_request_info make_request(const fields& args)
+{
+  std::string out{"   DIGEST   "};
+  write_fields(out, args);
+
+  http::http_request_info request{};
+  request.m_http_method_str = "NOP";
+  request.m_header_info.m_etc_fields.push_back(
+    std::make_pair(u8"authorization", std::move(out))
+  );
+  return request;
+}
+
+http::http_response_info make_response(const auth_responses& choices)
+{
+  http::http_response_info response{};
+  for (const auto& choice : choices)
+  {
+    std::string out{"   DIGEST   "};
+    write_fields(out, choice);
+
+    response.m_header_info.m_etc_fields.push_back(
+      std::make_pair(u8"WWW-authenticate", std::move(out))
+    );
+  }
+  return response;
+}
+
+bool has_same_fields(const auth_responses& in)
+{
+  const std::vector<std::string> check{u8"nonce", u8"qop", u8"realm", u8"stale"};
+  
+  auto current = in.begin();
+  const auto end = in.end();
+  if (current == end)
+    return true;
+
+  ++current;
+  for ( ; current != end; ++current )
+  {
+    for (const auto& field : check)
+    {
+      const std::string& expected = in[0].at(field);
+      const std::string& actual = current->at(field);
+      EXPECT_EQ(expected, actual);
+      if (expected != actual)
+        return false;
+    }
+  }
+  return true;
+}
+
+bool is_unauthorized(const http::http_response_info& response)
+{
+  EXPECT_EQ(401, response.m_response_code);
+  EXPECT_STREQ(u8"Unauthorized", response.m_response_comment.c_str());
+  EXPECT_STREQ(u8"text/html", response.m_mime_tipe.c_str());
+  return response.m_response_code == 401 &&
+    response.m_response_comment == u8"Unauthorized" &&
+    response.m_mime_tipe == u8"text/html";
+}
+
+fields parse_fields(const std::string& value)
+{
+  namespace qi = boost::spirit::qi;
+
+  fields out{};
+  const bool rc = qi::parse(
+    value.begin(), value.end(),
+    qi::lit(u8"Digest ") >> ((
+        +qi::ascii::alpha >>
+        qi::lit('=') >> (
+          (qi::lit('"') >> +(qi::ascii::char_ - '"') >> qi::lit('"')) |
+          +(qi::ascii::graph - qi::ascii::char_(u8"()<>@,;:\\\"/[]?={}"))
+        )
+      ) % ','
+    ) >> qi::eoi,
+    out
+  );
+  if (!rc)
+    throw std::runtime_error{"Bad field given in HTTP header"};
+
+  return out;
+}
+
+auth_responses parse_response(const http::http_response_info& response)
+{
+  auth_responses result{};
+
+  const auto end = response.m_additional_fields.end();
+  for (auto current = response.m_additional_fields.begin();; ++current)
+  {
+    current = std::find_if(current, end, [] (const std::pair<std::string, std::string>& field) {
+        return boost::equals(u8"WWW-authenticate", field.first);
+    });
+
+    if (current == end)
+      return result;
+
+    result.push_back(parse_fields(current->second));
+  }
+  return result;
+}
+
+std::string md5_hex(const std::string& in)
+{
+  md5::MD5_CTX ctx{};
+  md5::MD5Init(std::addressof(ctx));
+  md5::MD5Update(
+    std::addressof(ctx),
+    reinterpret_cast<const std::uint8_t*>(in.data()),
+    in.size()
+  );
+
+  std::array<std::uint8_t, 16> digest{{}};
+  md5::MD5Final(digest.data(), std::addressof(ctx));
+  return epee::string_tools::pod_to_hex(digest);
+}
+
+std::string get_a1(const http::login& user, const fields& src)
+{
+  const std::string& realm = src.at(u8"realm");
+  return boost::join(
+    std::vector<std::string>{user.username, realm, user.password}, u8":"
+  );
+}
+
+std::string get_a1(const http::login& user, const auth_responses& responses)
+{
+  return get_a1(user, responses.at(0));
+}
+
+std::string get_a1_sess(const http::login& user, const std::string& cnonce, const auth_responses& responses)
+{
+  const std::string& nonce = responses.at(0).at(u8"nonce");
+  return boost::join(
+    std::vector<std::string>{md5_hex(get_a1(user, responses)), nonce, cnonce}, u8":"
+  );
+}
+
+std::string get_a2(const std::string& uri)
+{
+  return boost::join(std::vector<std::string>{"NOP", uri}, u8":");
+}
+
+std::string get_nc(std::uint32_t count)
+{
+  namespace karma = boost::spirit::karma;
+  std::string out;
+  karma::generate(
+    std::back_inserter(out),
+    karma::right_align(8, '0')[karma::uint_generator<std::uint32_t, 16>{}],
+    count
+  );
+
+  return out;
+}
+}
+
+TEST(HTTP_Server_Auth, NotRequired)
+{
+  http::http_server_auth auth{};
+  EXPECT_FALSE(auth.get_response(http::http_request_info{}));
+}
+
+TEST(HTTP_Server_Auth, MissingAuth)
+{
+  http::http_server_auth auth{{"foo", "bar"}};
+  EXPECT_TRUE(bool(auth.get_response(http::http_request_info{})));
+  {
+    http::http_request_info request{};
+    request.m_header_info.m_etc_fields.push_back({"\xFF", "\xFF"});
+    EXPECT_TRUE(bool(auth.get_response(request)));
+  }
+}
+
+TEST(HTTP_Server_Auth, BadSyntax)
+{
+  http::http_server_auth auth{{"foo", "bar"}};
+  EXPECT_TRUE(bool(auth.get_response(make_request({{u8"algorithm", "fo\xFF"}}))));
+  EXPECT_TRUE(bool(auth.get_response(make_request({{u8"cnonce", "\"000\xFF\""}}))));
+  EXPECT_TRUE(bool(auth.get_response(make_request({{u8"cnonce \xFF =", "\"000\xFF\""}}))));
+  EXPECT_TRUE(bool(auth.get_response(make_request({{u8" \xFF cnonce", "\"000\xFF\""}}))));
+}
+
+TEST(HTTP_Server_Auth, MD5)
+{
+  http::login user{"foo", "bar"};
+  http::http_server_auth auth{user};
+
+  const auto response = auth.get_response(make_request(fields{}));
+  ASSERT_TRUE(bool(response));
+  EXPECT_TRUE(is_unauthorized(*response));
+
+  const auto fields = parse_response(*response);
+  ASSERT_LE(2u, fields.size());
+  EXPECT_TRUE(has_same_fields(fields));
+
+  const std::string& nonce = fields[0].at(u8"nonce");
+  EXPECT_EQ(24, nonce.size());
+
+  const std::string uri{"/some_foo_thing"};
+
+  const std::string a1 = get_a1(user, fields);
+  const std::string a2 = get_a2(uri);
+
+  const std::string auth_code = md5_hex(
+    boost::join(std::vector<std::string>{md5_hex(a1), nonce, md5_hex(a2)}, u8":")
+  );
+
+  const auto request = make_request({
+    {u8"nonce", quoted(nonce)},
+    {u8"realm", quoted(fields[0].at(u8"realm"))},
+    {u8"response", quoted(auth_code)},
+    {u8"uri", quoted(uri)},
+    {u8"username", quoted(user.username)}
+  });
+
+  EXPECT_FALSE(bool(auth.get_response(request)));
+
+  const auto response2 = auth.get_response(request);
+  ASSERT_TRUE(bool(response2));
+  EXPECT_TRUE(is_unauthorized(*response2));
+
+  const auto fields2 = parse_response(*response2);
+  ASSERT_LE(2u, fields2.size());
+  EXPECT_TRUE(has_same_fields(fields2));
+
+  EXPECT_NE(nonce, fields2[0].at(u8"nonce"));
+  EXPECT_STREQ(u8"true", fields2[0].at(u8"stale").c_str());
+}
+
+TEST(HTTP_Server_Auth, MD5_sess)
+{
+  constexpr const char cnonce[] = "not a good cnonce";
+
+  http::login user{"foo", "bar"};
+  http::http_server_auth auth{user};
+
+  const auto response = auth.get_response(make_request(fields{}));
+  ASSERT_TRUE(bool(response));
+  EXPECT_TRUE(is_unauthorized(*response));
+
+  const auto fields = parse_response(*response);
+  ASSERT_LE(2u, fields.size());
+  EXPECT_TRUE(has_same_fields(fields));
+
+  const std::string& nonce = fields[0].at(u8"nonce");
+  EXPECT_EQ(24, nonce.size());
+
+  const std::string uri{"/some_foo_thing"};
+
+  const std::string a1 = get_a1_sess(user, cnonce, fields);
+  const std::string a2 = get_a2(uri);
+
+  const std::string auth_code = md5_hex(
+    boost::join(std::vector<std::string>{md5_hex(a1), nonce, md5_hex(a2)}, u8":")
+  );
+
+  const auto request = make_request({
+    {u8"algorithm", u8"md5-sess"},
+    {u8"cnonce", quoted(cnonce)},
+    {u8"nonce", quoted(nonce)},
+    {u8"realm", quoted(fields[0].at(u8"realm"))},
+    {u8"response", quoted(auth_code)},
+    {u8"uri", quoted(uri)},
+    {u8"username", quoted(user.username)}
+  });
+
+  EXPECT_FALSE(bool(auth.get_response(request)));
+
+  const auto response2 = auth.get_response(request);
+  ASSERT_TRUE(bool(response2));
+  EXPECT_TRUE(is_unauthorized(*response2));
+
+  const auto fields2 = parse_response(*response2);
+  ASSERT_LE(2u, fields2.size());
+  EXPECT_TRUE(has_same_fields(fields2));
+
+  EXPECT_NE(nonce, fields2[0].at(u8"nonce"));
+  EXPECT_STREQ(u8"true", fields2[0].at(u8"stale").c_str());
+}
+
+TEST(HTTP_Server_Auth, MD5_auth)
+{
+  constexpr const char cnonce[] = "not a nonce";
+  constexpr const char qop[] = "auth";
+
+  http::login user{"foo", "bar"};
+  http::http_server_auth auth{user};
+
+  const auto response = auth.get_response(make_request(fields{}));
+  ASSERT_TRUE(bool(response));
+  EXPECT_TRUE(is_unauthorized(*response));
+
+  const auto parsed = parse_response(*response);
+  ASSERT_LE(2u, parsed.size());
+  EXPECT_TRUE(has_same_fields(parsed));
+
+  const std::string& nonce = parsed[0].at(u8"nonce");
+  EXPECT_EQ(24, nonce.size());
+
+  const std::string uri{"/some_foo_thing"};
+
+  const std::string a1 = get_a1(user, parsed);
+  const std::string a2 = get_a2(uri);
+  std::string nc = get_nc(1);
+
+  const auto generate_auth = [&] {
+    return md5_hex(
+      boost::join(
+        std::vector<std::string>{md5_hex(a1), nonce, nc, cnonce, qop, md5_hex(a2)}, u8":"
+      )
+    );
+  };
+
+  fields args{
+    {u8"algorithm", quoted(u8"md5")},
+    {u8"cnonce", quoted(cnonce)},
+    {u8"nc", nc},
+    {u8"nonce", quoted(nonce)},
+    {u8"qop", quoted(qop)},
+    {u8"realm", quoted(parsed[0].at(u8"realm"))},
+    {u8"response", quoted(generate_auth())},
+    {u8"uri", quoted(uri)},
+    {u8"username", quoted(user.username)}
+  };
+
+  const auto request = make_request(args);
+  EXPECT_FALSE(bool(auth.get_response(request)));
+
+  for (unsigned i = 2; i < 20; ++i)
+  {
+    nc = get_nc(i);
+    args.at(u8"nc") = nc;
+    args.at(u8"response") = quoted(generate_auth());
+    EXPECT_FALSE(auth.get_response(make_request(args)));
+  }
+
+  const auto replay = auth.get_response(request);
+  ASSERT_TRUE(bool(replay));
+  EXPECT_TRUE(is_unauthorized(*replay));
+
+  const auto parsed_replay = parse_response(*replay);
+  ASSERT_LE(2u, parsed_replay.size());
+  EXPECT_TRUE(has_same_fields(parsed_replay));
+
+  EXPECT_NE(nonce, parsed_replay[0].at(u8"nonce"));
+  EXPECT_STREQ(u8"true", parsed_replay[0].at(u8"stale").c_str());
+}
+
+TEST(HTTP_Server_Auth, MD5_sess_auth)
+{
+  constexpr const char cnonce[] = "not a nonce";
+  constexpr const char qop[] = "auth";
+
+  http::login user{"foo", "bar"};
+  http::http_server_auth auth{user};
+
+  const auto response = auth.get_response(make_request(fields{}));
+  ASSERT_TRUE(bool(response));
+  EXPECT_TRUE(is_unauthorized(*response));
+
+  const auto parsed = parse_response(*response);
+  ASSERT_LE(2u, parsed.size());
+  EXPECT_TRUE(has_same_fields(parsed));
+
+  const std::string& nonce = parsed[0].at(u8"nonce");
+  EXPECT_EQ(24, nonce.size());
+
+  const std::string uri{"/some_foo_thing"};
+
+  const std::string a1 = get_a1_sess(user, cnonce, parsed);
+  const std::string a2 = get_a2(uri);
+  std::string nc = get_nc(1);
+
+  const auto generate_auth = [&] {
+    return md5_hex(
+      boost::join(
+        std::vector<std::string>{md5_hex(a1), nonce, nc, cnonce, qop, md5_hex(a2)}, u8":"
+      )
+    );
+  };
+
+  fields args{
+    {u8"algorithm", u8"md5-sess"},
+    {u8"cnonce", quoted(cnonce)},
+    {u8"nc", nc},
+    {u8"nonce", quoted(nonce)},
+    {u8"qop", qop},
+    {u8"realm", quoted(parsed[0].at(u8"realm"))},
+    {u8"response", quoted(generate_auth())},
+    {u8"uri", quoted(uri)},
+    {u8"username", quoted(user.username)}
+  };
+
+  const auto request = make_request(args);
+  EXPECT_FALSE(bool(auth.get_response(request)));
+
+  for (unsigned i = 2; i < 20; ++i)
+  {
+    nc = get_nc(i);
+    args.at(u8"nc") = nc;
+    args.at(u8"response") = quoted(generate_auth());
+    EXPECT_FALSE(auth.get_response(make_request(args)));
+  }
+
+  const auto replay = auth.get_response(request);
+  ASSERT_TRUE(bool(replay));
+  EXPECT_TRUE(is_unauthorized(*replay));
+
+  const auto parsed_replay = parse_response(*replay);
+  ASSERT_LE(2u, parsed_replay.size());
+  EXPECT_TRUE(has_same_fields(parsed_replay));
+
+  EXPECT_NE(nonce, parsed_replay[0].at(u8"nonce"));
+  EXPECT_STREQ(u8"true", parsed_replay[0].at(u8"stale").c_str());
+}
+
+
+TEST(HTTP_Auth, DogFood)
+{
+  const auto add_auth_field = [] (http::http_request_info& request, http::http_client_auth& client)
+  {
+    auto field = client.get_auth_field(request.m_http_method_str, request.m_URI);
+    EXPECT_TRUE(bool(field));
+    if (!field)
+      return false;
+    request.m_header_info.m_etc_fields.push_back(std::move(*field));
+    return true;
+  };
+
+  const http::login user{"some_user", "ultimate password"};
+
+  http::http_server_auth server{user};
+  http::http_client_auth client{user};
+
+  http::http_request_info request{};
+  request.m_http_method_str = "GET";
+  request.m_URI = "/FOO";
+
+  auto response = server.get_response(request);
+  ASSERT_TRUE(bool(response));
+  EXPECT_TRUE(is_unauthorized(*response));
+  EXPECT_TRUE(response->m_header_info.m_etc_fields.empty());
+  response->m_header_info.m_etc_fields = response->m_additional_fields;
+
+  EXPECT_EQ(http::http_client_auth::kSuccess, client.handle_401(*response));
+  EXPECT_TRUE(add_auth_field(request, client));
+  EXPECT_FALSE(bool(server.get_response(request)));
+
+  for (unsigned i = 0; i < 1000; ++i)
+  {
+    request.m_http_method_str += std::to_string(i);
+    request.m_header_info.m_etc_fields.clear();
+    EXPECT_TRUE(add_auth_field(request, client));
+    EXPECT_FALSE(bool(server.get_response(request)));
+  }
+
+  // resetting counter should be rejected by server
+  request.m_header_info.m_etc_fields.clear();
+  client = http::http_client_auth{user};
+  EXPECT_EQ(http::http_client_auth::kSuccess, client.handle_401(*response));
+  EXPECT_TRUE(add_auth_field(request, client));
+
+  auto response2 = server.get_response(request);
+  ASSERT_TRUE(bool(response2));
+  EXPECT_TRUE(is_unauthorized(*response2));
+  EXPECT_TRUE(response2->m_header_info.m_etc_fields.empty());
+  response2->m_header_info.m_etc_fields = response2->m_additional_fields;
+
+  const auth_responses parsed1 = parse_response(*response);
+  const auth_responses parsed2 = parse_response(*response2);
+  ASSERT_LE(1u, parsed1.size());
+  ASSERT_LE(1u, parsed2.size());
+  EXPECT_NE(parsed1[0].at(u8"nonce"), parsed2[0].at(u8"nonce"));
+
+  // with stale=true client should reset
+  request.m_header_info.m_etc_fields.clear();
+  EXPECT_EQ(http::http_client_auth::kSuccess, client.handle_401(*response2));
+  EXPECT_TRUE(add_auth_field(request, client));
+  EXPECT_FALSE(bool(server.get_response(request)));
+
+  // client should give up if stale=false
+  EXPECT_EQ(http::http_client_auth::kBadPassword, client.handle_401(*response));
+}
+
+TEST(HTTP_Client_Auth, Unavailable)
+{
+  http::http_client_auth auth{};
+  EXPECT_EQ(http::http_client_auth::kBadPassword, auth.handle_401(http::http_response_info{}));
+  EXPECT_FALSE(bool(auth.get_auth_field("GET", "/file")));
+}
+
+TEST(HTTP_Client_Auth, MissingAuthenticate)
+{
+  http::http_client_auth auth{{"foo", "bar"}};
+  EXPECT_EQ(http::http_client_auth::kParseFailure, auth.handle_401(http::http_response_info{}));
+  EXPECT_FALSE(bool(auth.get_auth_field("POST", "/\xFFname")));
+  {
+    http::http_response_info response{};
+    response.m_additional_fields.push_back({"\xFF", "\xFF"});
+    EXPECT_EQ(http::http_client_auth::kParseFailure, auth.handle_401(response));
+  }
+  EXPECT_FALSE(bool(auth.get_auth_field("DELETE", "/file/does/not/exist")));
+}
+
+TEST(HTTP_Client_Auth, BadSyntax)
+{
+  http::http_client_auth auth{{"foo", "bar"}};
+  EXPECT_EQ(http::http_client_auth::kParseFailure, auth.handle_401(make_response({{{u8"realm", "fo\xFF"}}})));
+  EXPECT_EQ(http::http_client_auth::kParseFailure, auth.handle_401(make_response({{{u8"domain", "fo\xFF"}}})));
+  EXPECT_EQ(http::http_client_auth::kParseFailure, auth.handle_401(make_response({{{u8"nonce", "fo\xFF"}}})));
+  EXPECT_EQ(http::http_client_auth::kParseFailure, auth.handle_401(make_response({{{u8"nonce \xFF =", "fo\xFF"}}})));
+  EXPECT_EQ(http::http_client_auth::kParseFailure, auth.handle_401(make_response({{{u8" \xFF nonce", "fo\xFF"}}})));
+}
+
+TEST(HTTP_Client_Auth, MD5)
+{
+  constexpr char method[] = "NOP";
+  constexpr char nonce[] = "some crazy nonce";
+  constexpr char realm[] = "the only realm";
+  constexpr char uri[] = "/some_file";
+
+  const http::login user{"foo", "bar"};
+  http::http_client_auth auth{user};
+
+  auto response = make_response({
+    {
+      {u8"domain", quoted("ignored")},
+      {u8"nonce", quoted(nonce)},
+      {u8"REALM", quoted(realm)}
+    },
+    {
+      {u8"algorithm", "null"},
+      {u8"domain", quoted("ignored")},
+      {u8"nonce", quoted(std::string{"e"} + nonce)},
+      {u8"realm", quoted(std::string{"e"} + realm)}
+    },
+  });
+
+  EXPECT_EQ(http::http_client_auth::kSuccess, auth.handle_401(response));
+  const auto auth_field = auth.get_auth_field(method, uri);
+  ASSERT_TRUE(bool(auth_field));
+
+  const auto parsed = parse_fields(auth_field->second);
+  EXPECT_STREQ(u8"Authorization", auth_field->first.c_str());
+  EXPECT_EQ(parsed.end(), parsed.find(u8"opaque"));
+  EXPECT_EQ(parsed.end(), parsed.find(u8"qop"));
+  EXPECT_EQ(parsed.end(), parsed.find(u8"nc"));
+  EXPECT_STREQ(u8"MD5", parsed.at(u8"algorithm").c_str());
+  EXPECT_STREQ(nonce, parsed.at(u8"nonce").c_str());
+  EXPECT_STREQ(uri, parsed.at(u8"uri").c_str());
+  EXPECT_EQ(user.username, parsed.at(u8"username"));
+  EXPECT_STREQ(realm, parsed.at(u8"realm").c_str());
+
+  const std::string a1 = get_a1(user, parsed);
+  const std::string a2 = get_a2(uri);
+  const std::string auth_code = md5_hex(
+    boost::join(std::vector<std::string>{md5_hex(a1), nonce, md5_hex(a2)}, u8":")
+  );
+  EXPECT_TRUE(boost::iequals(auth_code, parsed.at(u8"response")));
+  {
+    const auto auth_field_dup = auth.get_auth_field(method, uri);
+    ASSERT_TRUE(bool(auth_field_dup));
+    EXPECT_EQ(*auth_field, *auth_field_dup);
+  }
+
+
+  EXPECT_EQ(http::http_client_auth::kBadPassword, auth.handle_401(response));
+  response.m_header_info.m_etc_fields.front().second.append(u8"," + write_fields({{u8"stale", u8"TRUE"}}));
+  EXPECT_EQ(http::http_client_auth::kSuccess, auth.handle_401(response));
+}
+
+TEST(HTTP_Client_Auth, MD5_auth)
+{
+  constexpr char cnonce[] = "";
+  constexpr char method[] = "NOP";
+  constexpr char nonce[] = "some crazy nonce";
+  constexpr char opaque[] = "this is the opaque";
+  constexpr char qop[] = u8"ignore,auth,ignore";
+  constexpr char realm[] = "the only realm";
+  constexpr char uri[] = "/some_file";
+
+  const http::login user{"foo", "bar"};
+  http::http_client_auth auth{user};
+
+  auto response = make_response({
+    {
+      {u8"algorithm", u8"MD5"},
+      {u8"domain", quoted("ignored")},
+      {u8"nonce", quoted(std::string{"e"} + nonce)},
+      {u8"realm", quoted(std::string{"e"} + realm)},
+      {u8"qop", quoted("some,thing,to,ignore")}
+    },
+    {
+      {u8"algorIthm", quoted(u8"md5")},
+      {u8"domain", quoted("ignored")},
+      {u8"noNce", quoted(nonce)},
+      {u8"opaque", quoted(opaque)},
+      {u8"realm", quoted(realm)},
+      {u8"QoP", quoted(qop)}
+    }
+  });
+
+  EXPECT_EQ(http::http_client_auth::kSuccess, auth.handle_401(response));
+
+  for (unsigned i = 1; i < 1000; ++i)
+  {
+    const std::string nc = get_nc(i);
+
+    const auto auth_field = auth.get_auth_field(method, uri);
+    ASSERT_TRUE(bool(auth_field));
+
+    const auto parsed = parse_fields(auth_field->second);
+    EXPECT_STREQ(u8"Authorization", auth_field->first.c_str());
+    EXPECT_STREQ(u8"MD5", parsed.at(u8"algorithm").c_str());
+    EXPECT_STREQ(nonce, parsed.at(u8"nonce").c_str());
+    EXPECT_STREQ(opaque, parsed.at(u8"opaque").c_str());
+    EXPECT_STREQ(u8"auth", parsed.at(u8"qop").c_str());
+    EXPECT_STREQ(uri, parsed.at(u8"uri").c_str());
+    EXPECT_EQ(user.username, parsed.at(u8"username"));
+    EXPECT_STREQ(realm, parsed.at(u8"realm").c_str());
+    EXPECT_EQ(nc, parsed.at(u8"nc"));
+
+    const std::string a1 = get_a1(user, parsed);
+    const std::string a2 = get_a2(uri);
+    const std::string auth_code = md5_hex(
+      boost::join(std::vector<std::string>{md5_hex(a1), nonce, nc, cnonce, u8"auth", md5_hex(a2)}, u8":")
+    );
+    EXPECT_TRUE(boost::iequals(auth_code, parsed.at(u8"response")));
+  }
+
+  EXPECT_EQ(http::http_client_auth::kBadPassword, auth.handle_401(response));
+  response.m_header_info.m_etc_fields.back().second.append(u8"," + write_fields({{u8"stale", u8"trUe"}}));
+  EXPECT_EQ(http::http_client_auth::kSuccess, auth.handle_401(response));
+}
+
+
+TEST(HTTP, Add_Field)
+{
+  std::string str{"leading text"};
+  epee::net_utils::http::add_field(str, "foo", "bar");
+  epee::net_utils::http::add_field(str, std::string("bar"), std::string("foo"));
+  epee::net_utils::http::add_field(str, {"moarbars", "moarfoo"});
+
+  EXPECT_STREQ("leading textfoo: bar\r\nbar: foo\r\nmoarbars: moarfoo\r\n", str.c_str());
+}