Kowalski, Kamil | 2b7981f | 2018-01-31 13:24:59 +0100 | [diff] [blame] | 1 | #pragma once |
| 2 | |
Kowalski, Kamil | 2b7981f | 2018-01-31 13:24:59 +0100 | [diff] [blame] | 3 | #include <crow/app.h> |
| 4 | #include <crow/http_request.h> |
| 5 | #include <crow/http_response.h> |
Ed Tanous | 1abe55e | 2018-09-05 08:30:59 -0700 | [diff] [blame^] | 6 | |
Kowalski, Kamil | 2b7981f | 2018-01-31 13:24:59 +0100 | [diff] [blame] | 7 | #include <boost/container/flat_map.hpp> |
| 8 | #include <boost/uuid/uuid.hpp> |
| 9 | #include <boost/uuid/uuid_generators.hpp> |
| 10 | #include <boost/uuid/uuid_io.hpp> |
Ed Tanous | 1abe55e | 2018-09-05 08:30:59 -0700 | [diff] [blame^] | 11 | #include <nlohmann/json.hpp> |
| 12 | #include <pam_authenticate.hpp> |
| 13 | #include <random> |
| 14 | #include <webassets.hpp> |
Kowalski, Kamil | 2b7981f | 2018-01-31 13:24:59 +0100 | [diff] [blame] | 15 | |
Ed Tanous | 1abe55e | 2018-09-05 08:30:59 -0700 | [diff] [blame^] | 16 | namespace crow |
| 17 | { |
Kowalski, Kamil | 2b7981f | 2018-01-31 13:24:59 +0100 | [diff] [blame] | 18 | |
Ed Tanous | 1abe55e | 2018-09-05 08:30:59 -0700 | [diff] [blame^] | 19 | namespace persistent_data |
| 20 | { |
Kowalski, Kamil | 2b7981f | 2018-01-31 13:24:59 +0100 | [diff] [blame] | 21 | |
Ed Tanous | 1abe55e | 2018-09-05 08:30:59 -0700 | [diff] [blame^] | 22 | enum class PersistenceType |
| 23 | { |
| 24 | TIMEOUT, // User session times out after a predetermined amount of time |
| 25 | SINGLE_REQUEST // User times out once this request is completed. |
Kowalski, Kamil | 2b7981f | 2018-01-31 13:24:59 +0100 | [diff] [blame] | 26 | }; |
| 27 | |
Ed Tanous | 1abe55e | 2018-09-05 08:30:59 -0700 | [diff] [blame^] | 28 | struct UserSession |
| 29 | { |
| 30 | std::string uniqueId; |
| 31 | std::string sessionToken; |
| 32 | std::string username; |
| 33 | std::string csrfToken; |
| 34 | std::chrono::time_point<std::chrono::steady_clock> lastUpdated; |
| 35 | PersistenceType persistence; |
Kowalski, Kamil | 5cef0f7 | 2018-02-15 15:26:51 +0100 | [diff] [blame] | 36 | |
Ed Tanous | 1abe55e | 2018-09-05 08:30:59 -0700 | [diff] [blame^] | 37 | /** |
| 38 | * @brief Fills object with data from UserSession's JSON representation |
| 39 | * |
| 40 | * This replaces nlohmann's from_json to ensure no-throw approach |
| 41 | * |
| 42 | * @param[in] j JSON object from which data should be loaded |
| 43 | * |
| 44 | * @return a shared pointer if data has been loaded properly, nullptr |
| 45 | * otherwise |
| 46 | */ |
| 47 | static std::shared_ptr<UserSession> fromJson(const nlohmann::json& j) |
| 48 | { |
| 49 | std::shared_ptr<UserSession> userSession = |
| 50 | std::make_shared<UserSession>(); |
| 51 | for (const auto& element : j.items()) |
| 52 | { |
| 53 | const std::string* thisValue = |
| 54 | element.value().get_ptr<const std::string*>(); |
| 55 | if (thisValue == nullptr) |
| 56 | { |
| 57 | BMCWEB_LOG_ERROR << "Error reading persistent store. Property " |
| 58 | << element.key() << " was not of type string"; |
| 59 | return nullptr; |
| 60 | } |
| 61 | if (element.key() == "unique_id") |
| 62 | { |
| 63 | userSession->uniqueId = *thisValue; |
| 64 | } |
| 65 | else if (element.key() == "session_token") |
| 66 | { |
| 67 | userSession->sessionToken = *thisValue; |
| 68 | } |
| 69 | else if (element.key() == "csrf_token") |
| 70 | { |
| 71 | userSession->csrfToken = *thisValue; |
| 72 | } |
| 73 | else if (element.key() == "username") |
| 74 | { |
| 75 | userSession->username = *thisValue; |
| 76 | } |
| 77 | else |
| 78 | { |
| 79 | BMCWEB_LOG_ERROR |
| 80 | << "Got unexpected property reading persistent file: " |
| 81 | << element.key(); |
| 82 | return nullptr; |
| 83 | } |
| 84 | } |
| 85 | |
| 86 | // For now, sessions that were persisted through a reboot get their idle |
| 87 | // timer reset. This could probably be overcome with a better |
| 88 | // understanding of wall clock time and steady timer time, possibly |
| 89 | // persisting values with wall clock time instead of steady timer, but |
| 90 | // the tradeoffs of all the corner cases involved are non-trivial, so |
| 91 | // this is done temporarily |
| 92 | userSession->lastUpdated = std::chrono::steady_clock::now(); |
| 93 | userSession->persistence = PersistenceType::TIMEOUT; |
| 94 | |
| 95 | return userSession; |
Kowalski, Kamil | 5cef0f7 | 2018-02-15 15:26:51 +0100 | [diff] [blame] | 96 | } |
Kowalski, Kamil | 2b7981f | 2018-01-31 13:24:59 +0100 | [diff] [blame] | 97 | }; |
| 98 | |
Kowalski, Kamil | 2b7981f | 2018-01-31 13:24:59 +0100 | [diff] [blame] | 99 | class Middleware; |
| 100 | |
Ed Tanous | 1abe55e | 2018-09-05 08:30:59 -0700 | [diff] [blame^] | 101 | class SessionStore |
| 102 | { |
| 103 | public: |
| 104 | std::shared_ptr<UserSession> generateUserSession( |
| 105 | const boost::string_view username, |
| 106 | PersistenceType persistence = PersistenceType::TIMEOUT) |
| 107 | { |
| 108 | // TODO(ed) find a secure way to not generate session identifiers if |
| 109 | // persistence is set to SINGLE_REQUEST |
| 110 | static constexpr std::array<char, 62> alphanum = { |
| 111 | '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'b', 'C', |
| 112 | 'D', 'E', 'F', 'g', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', |
| 113 | 'Q', 'r', 'S', 'T', 'U', 'v', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', |
| 114 | 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', |
| 115 | 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z'}; |
Kowalski, Kamil | 2b7981f | 2018-01-31 13:24:59 +0100 | [diff] [blame] | 116 | |
Ed Tanous | 1abe55e | 2018-09-05 08:30:59 -0700 | [diff] [blame^] | 117 | // entropy: 30 characters, 62 possibilities. log2(62^30) = 178 bits of |
| 118 | // entropy. OWASP recommends at least 60 |
| 119 | // https://www.owasp.org/index.php/Session_Management_Cheat_Sheet#Session_ID_Entropy |
| 120 | std::string sessionToken; |
| 121 | sessionToken.resize(20, '0'); |
| 122 | std::uniform_int_distribution<int> dist(0, alphanum.size() - 1); |
| 123 | for (int i = 0; i < sessionToken.size(); ++i) |
| 124 | { |
| 125 | sessionToken[i] = alphanum[dist(rd)]; |
Kowalski, Kamil | 2b7981f | 2018-01-31 13:24:59 +0100 | [diff] [blame] | 126 | } |
Ed Tanous | 1abe55e | 2018-09-05 08:30:59 -0700 | [diff] [blame^] | 127 | // Only need csrf tokens for cookie based auth, token doesn't matter |
| 128 | std::string csrfToken; |
| 129 | csrfToken.resize(20, '0'); |
| 130 | for (int i = 0; i < csrfToken.size(); ++i) |
| 131 | { |
| 132 | csrfToken[i] = alphanum[dist(rd)]; |
| 133 | } |
| 134 | |
| 135 | std::string uniqueId; |
| 136 | uniqueId.resize(10, '0'); |
| 137 | for (int i = 0; i < uniqueId.size(); ++i) |
| 138 | { |
| 139 | uniqueId[i] = alphanum[dist(rd)]; |
| 140 | } |
| 141 | auto session = std::make_shared<UserSession>(UserSession{ |
| 142 | uniqueId, sessionToken, std::string(username), csrfToken, |
| 143 | std::chrono::steady_clock::now(), persistence}); |
| 144 | auto it = authTokens.emplace(std::make_pair(sessionToken, session)); |
| 145 | // Only need to write to disk if session isn't about to be destroyed. |
| 146 | needWrite = persistence == PersistenceType::TIMEOUT; |
| 147 | return it.first->second; |
Kowalski, Kamil | 2b7981f | 2018-01-31 13:24:59 +0100 | [diff] [blame] | 148 | } |
Ed Tanous | 1abe55e | 2018-09-05 08:30:59 -0700 | [diff] [blame^] | 149 | |
| 150 | std::shared_ptr<UserSession> |
| 151 | loginSessionByToken(const boost::string_view token) |
| 152 | { |
| 153 | applySessionTimeouts(); |
| 154 | auto sessionIt = authTokens.find(std::string(token)); |
| 155 | if (sessionIt == authTokens.end()) |
| 156 | { |
| 157 | return nullptr; |
| 158 | } |
| 159 | std::shared_ptr<UserSession> userSession = sessionIt->second; |
| 160 | userSession->lastUpdated = std::chrono::steady_clock::now(); |
| 161 | return userSession; |
| 162 | } |
| 163 | |
| 164 | std::shared_ptr<UserSession> getSessionByUid(const boost::string_view uid) |
| 165 | { |
| 166 | applySessionTimeouts(); |
| 167 | // TODO(Ed) this is inefficient |
| 168 | auto sessionIt = authTokens.begin(); |
| 169 | while (sessionIt != authTokens.end()) |
| 170 | { |
| 171 | if (sessionIt->second->uniqueId == uid) |
| 172 | { |
| 173 | return sessionIt->second; |
| 174 | } |
| 175 | sessionIt++; |
| 176 | } |
| 177 | return nullptr; |
| 178 | } |
| 179 | |
| 180 | void removeSession(std::shared_ptr<UserSession> session) |
| 181 | { |
| 182 | authTokens.erase(session->sessionToken); |
| 183 | needWrite = true; |
| 184 | } |
| 185 | |
| 186 | std::vector<const std::string*> getUniqueIds( |
| 187 | bool getAll = true, |
| 188 | const PersistenceType& type = PersistenceType::SINGLE_REQUEST) |
| 189 | { |
| 190 | applySessionTimeouts(); |
| 191 | |
| 192 | std::vector<const std::string*> ret; |
| 193 | ret.reserve(authTokens.size()); |
| 194 | for (auto& session : authTokens) |
| 195 | { |
| 196 | if (getAll || type == session.second->persistence) |
| 197 | { |
| 198 | ret.push_back(&session.second->uniqueId); |
| 199 | } |
| 200 | } |
| 201 | return ret; |
| 202 | } |
| 203 | |
| 204 | bool needsWrite() |
| 205 | { |
| 206 | return needWrite; |
| 207 | } |
| 208 | int getTimeoutInSeconds() const |
| 209 | { |
| 210 | return std::chrono::seconds(timeoutInMinutes).count(); |
| 211 | }; |
| 212 | |
| 213 | // Persistent data middleware needs to be able to serialize our authTokens |
| 214 | // structure, which is private |
| 215 | friend Middleware; |
| 216 | |
| 217 | static SessionStore& getInstance() |
| 218 | { |
| 219 | static SessionStore sessionStore; |
| 220 | return sessionStore; |
| 221 | } |
| 222 | |
| 223 | SessionStore(const SessionStore&) = delete; |
| 224 | SessionStore& operator=(const SessionStore&) = delete; |
| 225 | |
| 226 | private: |
| 227 | SessionStore() : timeoutInMinutes(60) |
| 228 | { |
| 229 | } |
| 230 | |
| 231 | void applySessionTimeouts() |
| 232 | { |
| 233 | auto timeNow = std::chrono::steady_clock::now(); |
| 234 | if (timeNow - lastTimeoutUpdate > std::chrono::minutes(1)) |
| 235 | { |
| 236 | lastTimeoutUpdate = timeNow; |
| 237 | auto authTokensIt = authTokens.begin(); |
| 238 | while (authTokensIt != authTokens.end()) |
| 239 | { |
| 240 | if (timeNow - authTokensIt->second->lastUpdated >= |
| 241 | timeoutInMinutes) |
| 242 | { |
| 243 | authTokensIt = authTokens.erase(authTokensIt); |
| 244 | needWrite = true; |
| 245 | } |
| 246 | else |
| 247 | { |
| 248 | authTokensIt++; |
| 249 | } |
| 250 | } |
| 251 | } |
| 252 | } |
| 253 | std::chrono::time_point<std::chrono::steady_clock> lastTimeoutUpdate; |
| 254 | boost::container::flat_map<std::string, std::shared_ptr<UserSession>> |
| 255 | authTokens; |
| 256 | std::random_device rd; |
| 257 | bool needWrite{false}; |
| 258 | std::chrono::minutes timeoutInMinutes; |
Kowalski, Kamil | 2b7981f | 2018-01-31 13:24:59 +0100 | [diff] [blame] | 259 | }; |
| 260 | |
Ed Tanous | 1abe55e | 2018-09-05 08:30:59 -0700 | [diff] [blame^] | 261 | } // namespace persistent_data |
| 262 | } // namespace crow |
Borawski.Lukasz | 4b1b868 | 2018-04-04 12:50:16 +0200 | [diff] [blame] | 263 | |
| 264 | // to_json(...) definition for objects of UserSession type |
Ed Tanous | 1abe55e | 2018-09-05 08:30:59 -0700 | [diff] [blame^] | 265 | namespace nlohmann |
| 266 | { |
Borawski.Lukasz | 4b1b868 | 2018-04-04 12:50:16 +0200 | [diff] [blame] | 267 | template <> |
Ed Tanous | 1abe55e | 2018-09-05 08:30:59 -0700 | [diff] [blame^] | 268 | struct adl_serializer<std::shared_ptr<crow::persistent_data::UserSession>> |
| 269 | { |
| 270 | static void |
| 271 | to_json(nlohmann::json& j, |
| 272 | const std::shared_ptr<crow::persistent_data::UserSession>& p) |
| 273 | { |
| 274 | if (p->persistence != |
| 275 | crow::persistent_data::PersistenceType::SINGLE_REQUEST) |
| 276 | { |
| 277 | j = nlohmann::json{{"unique_id", p->uniqueId}, |
| 278 | {"session_token", p->sessionToken}, |
| 279 | {"username", p->username}, |
| 280 | {"csrf_token", p->csrfToken}}; |
| 281 | } |
Borawski.Lukasz | 4b1b868 | 2018-04-04 12:50:16 +0200 | [diff] [blame] | 282 | } |
Borawski.Lukasz | 4b1b868 | 2018-04-04 12:50:16 +0200 | [diff] [blame] | 283 | }; |
Ed Tanous | 1abe55e | 2018-09-05 08:30:59 -0700 | [diff] [blame^] | 284 | } // namespace nlohmann |