include/token_authorization_middleware.hpp - openbmc/bmcweb - Gitiles

 #pragma once

 #include <pam_authenticate.hpp>
 #include <persistent_data_middleware.hpp>
 #include <webassets.hpp>
 #include <random>
 #include <crow/app.h>
 #include <crow/common.h>
 #include <crow/http_request.h>
 #include <crow/http_response.h>
 #include <boost/container/flat_set.hpp>

 namespace crow {

 namespace TokenAuthorization {

 class Middleware {
  public:
   struct context {
     std::shared_ptr<crow::PersistentData::UserSession> session;
   };

   void before_handle(crow::request& req, response& res, context& ctx) {
     if (is_on_whitelist(req)) {
       return;
     }

     ctx.session = perform_xtoken_auth(req);
     if (ctx.session == nullptr) {
       ctx.session = perform_cookie_auth(req);
     }
     if (ctx.session == nullptr) {
       boost::string_view auth_header = req.get_header_value("Authorization");
       if (!auth_header.empty()) {
         // Reject any kind of auth other than basic or token
         if (boost::starts_with(auth_header, "Token ")) {
           ctx.session = perform_token_auth(auth_header);
         } else if (boost::starts_with(auth_header, "Basic ")) {
           ctx.session = perform_basic_auth(auth_header);
         }
       }
     }

     if (ctx.session == nullptr) {
       CROW_LOG_WARNING << "[AuthMiddleware] authorization failed";

       // If it's a browser connecting, don't send the HTTP authenticate header,
       // to avoid possible CSRF attacks with basic auth
       if (http_helpers::request_prefers_html(req)) {
         res.result(boost::beast::http::status::temporary_redirect);
         res.add_header("Location", "/#/login");
       } else {
         res.result(boost::beast::http::status::unauthorized);
         // only send the WWW-authenticate header if this isn't a xhr from the
         // browser.  most scripts,
         if (req.get_header_value("User-Agent").empty()) {
           res.add_header("WWW-Authenticate", "Basic");
         }
       }

       res.end();
       return;
     }

     // TODO get user privileges here and propagate it via MW context
     // else let the request continue unharmed
   }

   template <typename AllContext>
   void after_handle(request& req, response& res, context& ctx,
                     AllContext& allctx) {
     // TODO(ed) THis should really be handled by the persistent data
     // middleware, but because it is upstream, it doesn't have access to the
     // session information.  Should the data middleware persist the current
     // user session?
     if (ctx.session != nullptr &&
         ctx.session->persistence ==
             crow::PersistentData::PersistenceType::SINGLE_REQUEST) {
       PersistentData::session_store->remove_session(ctx.session);
     }
   }

  private:
   const std::shared_ptr<crow::PersistentData::UserSession> perform_basic_auth(
       boost::string_view auth_header) const {
     CROW_LOG_DEBUG << "[AuthMiddleware] Basic authentication";

     std::string auth_data;
     boost::string_view param = auth_header.substr(strlen("Basic "));
     if (!crow::utility::base64_decode(param, auth_data)) {
       return nullptr;
     }
     std::size_t separator = auth_data.find(':');
     if (separator == std::string::npos) {
       return nullptr;
     }

     std::string user = auth_data.substr(0, separator);
     separator += 1;
     if (separator > auth_data.size()) {
       return nullptr;
     }
     std::string pass = auth_data.substr(separator);

     CROW_LOG_DEBUG << "[AuthMiddleware] Authenticating user: " << user;

     if (!pam_authenticate_user(user, pass)) {
       return nullptr;
     }

     // TODO(ed) generate_user_session is a little expensive for basic
     // auth, as it generates some random identifiers that will never be
     // used.  This should have a "fast" path for when user tokens aren't
     // needed.
     // This whole flow needs to be revisited anyway, as we can't be
     // calling directly into pam for every request
     return PersistentData::session_store->generate_user_session(
         user, crow::PersistentData::PersistenceType::SINGLE_REQUEST);
   }

   const std::shared_ptr<crow::PersistentData::UserSession> perform_token_auth(
       boost::string_view auth_header) const {
     CROW_LOG_DEBUG << "[AuthMiddleware] Token authentication";

     boost::string_view token = auth_header.substr(strlen("Token "));
     auto session = PersistentData::session_store->login_session_by_token(token);
     return session;
   }

   const std::shared_ptr<crow::PersistentData::UserSession> perform_xtoken_auth(
       const crow::request& req) const {
     CROW_LOG_DEBUG << "[AuthMiddleware] X-Auth-Token authentication";

     boost::string_view token = req.get_header_value("X-Auth-Token");
     if (token.empty()) {
       return nullptr;
     }
     auto session = PersistentData::session_store->login_session_by_token(token);
     return session;
   }

   const std::shared_ptr<crow::PersistentData::UserSession> perform_cookie_auth(
       const crow::request& req) const {
     CROW_LOG_DEBUG << "[AuthMiddleware] Cookie authentication";

     boost::string_view cookie_value = req.get_header_value("Cookie");
     if (cookie_value.empty()) {
       return nullptr;
     }

     auto start_index = cookie_value.find("SESSION=");
     if (start_index == std::string::npos) {
       return nullptr;
     }
     start_index += sizeof("SESSION=") - 1;
     auto end_index = cookie_value.find(";", start_index);
     if (end_index == std::string::npos) {
       end_index = cookie_value.size();
     }
     boost::string_view auth_key =
         cookie_value.substr(start_index, end_index - start_index);

     const std::shared_ptr<crow::PersistentData::UserSession> session =
         PersistentData::session_store->login_session_by_token(auth_key);
     if (session == nullptr) {
       return nullptr;
     }
 #ifndef BMCWEB_INSECURE_DISABLE_CSRF_PREVENTION
     // RFC7231 defines methods that need csrf protection
     if (req.method() != "GET"_method) {
       boost::string_view csrf = req.get_header_value("X-XSRF-TOKEN");
       // Make sure both tokens are filled
       if (csrf.empty() || session->csrf_token.empty()) {
         return nullptr;
       }
       // Reject if csrf token not available
       if (csrf != session->csrf_token) {
         return nullptr;
       }
     }
 #endif
     return session;
   }

   // checks if request can be forwarded without authentication
   bool is_on_whitelist(const crow::request& req) const {
     // it's allowed to GET root node without authentica tion
     if ("GET"_method == req.method()) {
       if (req.url == "/redfish/v1" || req.url == "/redfish/v1/") {
         return true;
       } else if (crow::webassets::routes.find(std::string(req.url)) !=
                  crow::webassets::routes.end()) {
         return true;
       }
     }

     // it's allowed to POST on session collection & login without
     // authentication
     if ("POST"_method == req.method()) {
       if ((req.url == "/redfish/v1/SessionService/Sessions") ||
           (req.url == "/redfish/v1/SessionService/Sessions/") ||
           (req.url == "/login")) {
         return true;
       }
     }

     return false;
   }
 };

 // TODO(ed) see if there is a better way to allow middlewares to request
 // routes.
 // Possibly an init function on first construction?
 template <typename... Middlewares>
 void request_routes(Crow<Middlewares...>& app) {
   static_assert(
       black_magic::contains<PersistentData::Middleware, Middlewares...>::value,
       "TokenAuthorization middleware must be enabled in app to use "
       "auth routes");
   CROW_ROUTE(app, "/login")
       .methods(
           "POST"_method)([&](const crow::request& req, crow::response& res) {
         boost::string_view content_type = req.get_header_value("content-type");
         boost::string_view username;
         boost::string_view password;

         bool looks_like_ibm = false;

         // This object needs to be declared at this scope so the strings
         // within it are not destroyed before we can use them
         nlohmann::json login_credentials;
         // Check if auth was provided by a payload
         if (content_type == "application/json") {
           login_credentials = nlohmann::json::parse(req.body, nullptr, false);
           if (login_credentials.is_discarded()) {
             res.result(boost::beast::http::status::bad_request);
             res.end();
             return;
           }

           // check for username/password in the root object
           // THis method is how intel APIs authenticate
           nlohmann::json::iterator user_it = login_credentials.find("username");
           nlohmann::json::iterator pass_it = login_credentials.find("password");
           if (user_it != login_credentials.end() &&
               pass_it != login_credentials.end()) {
             const std::string* user_str =
                 user_it->get_ptr<const std::string*>();
             const std::string* pass_str =
                 pass_it->get_ptr<const std::string*>();
             if (user_str != nullptr && pass_str != nullptr) {
               username = *user_str;
               password = *pass_str;
             }
           } else {
             // Openbmc appears to push a data object that contains the same
             // keys (username and password), attempt to use that
             auto data_it = login_credentials.find("data");
             if (data_it != login_credentials.end()) {
               // Some apis produce an array of value ["username",
               // "password"]
               if (data_it->is_array()) {
                 if (data_it->size() == 2) {
                   nlohmann::json::iterator user_it2 = data_it->begin();
                   nlohmann::json::iterator pass_it2 = data_it->begin() + 1;
                   looks_like_ibm = true;
                   if (user_it2 != data_it->end() &&
                       pass_it2 != data_it->end()) {
                     const std::string* user_str =
                         user_it2->get_ptr<const std::string*>();
                     const std::string* pass_str =
                         pass_it2->get_ptr<const std::string*>();
                     if (user_str != nullptr && pass_str != nullptr) {
                       username = *user_str;
                       password = *pass_str;
                     }
                   }
                 }

               } else if (data_it->is_object()) {
                 nlohmann::json::iterator user_it2 = data_it->find("username");
                 nlohmann::json::iterator pass_it2 = data_it->find("password");
                 if (user_it2 != data_it->end() && pass_it2 != data_it->end()) {
                   const std::string* user_str =
                       user_it2->get_ptr<const std::string*>();
                   const std::string* pass_str =
                       pass_it2->get_ptr<const std::string*>();
                   if (user_str != nullptr && pass_str != nullptr) {
                     username = *user_str;
                     password = *pass_str;
                   }
                 }
               }
             }
           }
         } else {
           // check if auth was provided as a headers
           username = req.get_header_value("username");
           password = req.get_header_value("password");
         }

         if (!username.empty() && !password.empty()) {
           if (!pam_authenticate_user(username, password)) {
             res.result(boost::beast::http::status::unauthorized);
           } else {
             auto session =
                 PersistentData::session_store->generate_user_session(username);

             if (looks_like_ibm) {
               // IBM requires a very specific login structure, and doesn't
               // actually look at the status code.  TODO(ed).... Fix that
               // upstream
               res.json_value = {
                   {"data", "User '" + std::string(username) + "' logged in"},
                   {"message", "200 OK"},
                   {"status", "ok"}};

               // Hack alert.  Boost beast by default doesn't let you declare
               // multiple headers of the same name, and in most cases this is
               // fine.  Unfortunately here we need to set the Session cookie,
               // which requires the httpOnly attribute, as well as the XSRF
               // cookie, which requires it to not have an httpOnly attribute.
               // To get the behavior we want, we simply inject the second
               // "set-cookie" string into the value header, and get the result
               // we want, even though we are technicaly declaring two headers
               // here.
               res.add_header("Set-Cookie",
                              "XSRF-TOKEN=" + session->csrf_token +
                                  "; Secure\r\nSet-Cookie: SESSION=" +
                                  session->session_token + "; Secure; HttpOnly");
             } else {
               // if content type is json, assume json token
               res.json_value = {{"token", session->session_token}};
             }
           }

         } else {
           res.result(boost::beast::http::status::bad_request);
         }
         res.end();
       });

   CROW_ROUTE(app, "/logout")
       .methods("POST"_method)(
           [&](const crow::request& req, crow::response& res) {
             auto& session =
                 app.template get_context<TokenAuthorization::Middleware>(req)
                     .session;
             if (session != nullptr) {
               PersistentData::session_store->remove_session(session);
             }
             res.end();
             return;

           });
 }
 }  // namespace TokenAuthorization
 }  // namespace crow
	#pragma once

	#include <pam_authenticate.hpp>
	#include <persistent_data_middleware.hpp>
	#include <webassets.hpp>
	#include <random>
	#include <crow/app.h>
	#include <crow/common.h>
	#include <crow/http_request.h>
	#include <crow/http_response.h>
	#include <boost/container/flat_set.hpp>

	namespace crow {

	namespace TokenAuthorization {

	class Middleware {
	public:
	struct context {
	std::shared_ptr<crow::PersistentData::UserSession> session;
	};

	void before_handle(crow::request& req, response& res, context& ctx) {
	if (is_on_whitelist(req)) {
	return;
	}

	ctx.session = perform_xtoken_auth(req);
	if (ctx.session == nullptr) {
	ctx.session = perform_cookie_auth(req);
	}
	if (ctx.session == nullptr) {
	boost::string_view auth_header = req.get_header_value("Authorization");
	if (!auth_header.empty()) {
	// Reject any kind of auth other than basic or token
	if (boost::starts_with(auth_header, "Token ")) {
	ctx.session = perform_token_auth(auth_header);
	} else if (boost::starts_with(auth_header, "Basic ")) {
	ctx.session = perform_basic_auth(auth_header);
	}
	}
	}

	if (ctx.session == nullptr) {
	CROW_LOG_WARNING << "[AuthMiddleware] authorization failed";

	// If it's a browser connecting, don't send the HTTP authenticate header,
	// to avoid possible CSRF attacks with basic auth
	if (http_helpers::request_prefers_html(req)) {
	res.result(boost::beast::http::status::temporary_redirect);
	res.add_header("Location", "/#/login");
	} else {
	res.result(boost::beast::http::status::unauthorized);
	// only send the WWW-authenticate header if this isn't a xhr from the
	// browser. most scripts,
	if (req.get_header_value("User-Agent").empty()) {
	res.add_header("WWW-Authenticate", "Basic");
	}
	}

	res.end();
	return;
	}

	// TODO get user privileges here and propagate it via MW context
	// else let the request continue unharmed
	}

	template <typename AllContext>
	void after_handle(request& req, response& res, context& ctx,
	AllContext& allctx) {
	// TODO(ed) THis should really be handled by the persistent data
	// middleware, but because it is upstream, it doesn't have access to the
	// session information. Should the data middleware persist the current
	// user session?
	if (ctx.session != nullptr &&
	ctx.session->persistence ==
	crow::PersistentData::PersistenceType::SINGLE_REQUEST) {
	PersistentData::session_store->remove_session(ctx.session);
	}
	}

	private:
	const std::shared_ptr<crow::PersistentData::UserSession> perform_basic_auth(
	boost::string_view auth_header) const {
	CROW_LOG_DEBUG << "[AuthMiddleware] Basic authentication";

	std::string auth_data;
	boost::string_view param = auth_header.substr(strlen("Basic "));
	if (!crow::utility::base64_decode(param, auth_data)) {
	return nullptr;
	}
	std::size_t separator = auth_data.find(':');
	if (separator == std::string::npos) {
	return nullptr;
	}

	std::string user = auth_data.substr(0, separator);
	separator += 1;
	if (separator > auth_data.size()) {
	return nullptr;
	}
	std::string pass = auth_data.substr(separator);

	CROW_LOG_DEBUG << "[AuthMiddleware] Authenticating user: " << user;

	if (!pam_authenticate_user(user, pass)) {
	return nullptr;
	}

	// TODO(ed) generate_user_session is a little expensive for basic
	// auth, as it generates some random identifiers that will never be
	// used. This should have a "fast" path for when user tokens aren't
	// needed.
	// This whole flow needs to be revisited anyway, as we can't be
	// calling directly into pam for every request
	return PersistentData::session_store->generate_user_session(
	user, crow::PersistentData::PersistenceType::SINGLE_REQUEST);
	}

	const std::shared_ptr<crow::PersistentData::UserSession> perform_token_auth(
	boost::string_view auth_header) const {
	CROW_LOG_DEBUG << "[AuthMiddleware] Token authentication";

	boost::string_view token = auth_header.substr(strlen("Token "));
	auto session = PersistentData::session_store->login_session_by_token(token);
	return session;
	}

	const std::shared_ptr<crow::PersistentData::UserSession> perform_xtoken_auth(
	const crow::request& req) const {
	CROW_LOG_DEBUG << "[AuthMiddleware] X-Auth-Token authentication";

	boost::string_view token = req.get_header_value("X-Auth-Token");
	if (token.empty()) {
	return nullptr;
	}
	auto session = PersistentData::session_store->login_session_by_token(token);
	return session;
	}

	const std::shared_ptr<crow::PersistentData::UserSession> perform_cookie_auth(
	const crow::request& req) const {
	CROW_LOG_DEBUG << "[AuthMiddleware] Cookie authentication";

	boost::string_view cookie_value = req.get_header_value("Cookie");
	if (cookie_value.empty()) {
	return nullptr;
	}

	auto start_index = cookie_value.find("SESSION=");
	if (start_index == std::string::npos) {
	return nullptr;
	}
	start_index += sizeof("SESSION=") - 1;
	auto end_index = cookie_value.find(";", start_index);
	if (end_index == std::string::npos) {
	end_index = cookie_value.size();
	}
	boost::string_view auth_key =
	cookie_value.substr(start_index, end_index - start_index);

	const std::shared_ptr<crow::PersistentData::UserSession> session =
	PersistentData::session_store->login_session_by_token(auth_key);
	if (session == nullptr) {
	return nullptr;
	}
	#ifndef BMCWEB_INSECURE_DISABLE_CSRF_PREVENTION
	// RFC7231 defines methods that need csrf protection
	if (req.method() != "GET"_method) {
	boost::string_view csrf = req.get_header_value("X-XSRF-TOKEN");
	// Make sure both tokens are filled
	if (csrf.empty() \|\| session->csrf_token.empty()) {
	return nullptr;
	}
	// Reject if csrf token not available
	if (csrf != session->csrf_token) {
	return nullptr;
	}
	}
	#endif
	return session;
	}

	// checks if request can be forwarded without authentication
	bool is_on_whitelist(const crow::request& req) const {
	// it's allowed to GET root node without authentica tion
	if ("GET"_method == req.method()) {
	if (req.url == "/redfish/v1" \|\| req.url == "/redfish/v1/") {
	return true;
	} else if (crow::webassets::routes.find(std::string(req.url)) !=
	crow::webassets::routes.end()) {
	return true;
	}
	}

	// it's allowed to POST on session collection & login without
	// authentication
	if ("POST"_method == req.method()) {
	if ((req.url == "/redfish/v1/SessionService/Sessions") \|\|
	(req.url == "/redfish/v1/SessionService/Sessions/") \|\|
	(req.url == "/login")) {
	return true;
	}
	}

	return false;
	}
	};

	// TODO(ed) see if there is a better way to allow middlewares to request
	// routes.
	// Possibly an init function on first construction?
	template <typename... Middlewares>
	void request_routes(Crow<Middlewares...>& app) {
	static_assert(
	black_magic::contains<PersistentData::Middleware, Middlewares...>::value,
	"TokenAuthorization middleware must be enabled in app to use "
	"auth routes");
	CROW_ROUTE(app, "/login")
	.methods(
	"POST"_method)([&](const crow::request& req, crow::response& res) {
	boost::string_view content_type = req.get_header_value("content-type");
	boost::string_view username;
	boost::string_view password;

	bool looks_like_ibm = false;

	// This object needs to be declared at this scope so the strings
	// within it are not destroyed before we can use them
	nlohmann::json login_credentials;
	// Check if auth was provided by a payload
	if (content_type == "application/json") {
	login_credentials = nlohmann::json::parse(req.body, nullptr, false);
	if (login_credentials.is_discarded()) {
	res.result(boost::beast::http::status::bad_request);
	res.end();
	return;
	}

	// check for username/password in the root object
	// THis method is how intel APIs authenticate
	nlohmann::json::iterator user_it = login_credentials.find("username");
	nlohmann::json::iterator pass_it = login_credentials.find("password");
	if (user_it != login_credentials.end() &&
	pass_it != login_credentials.end()) {
	const std::string* user_str =
	user_it->get_ptr<const std::string*>();
	const std::string* pass_str =
	pass_it->get_ptr<const std::string*>();
	if (user_str != nullptr && pass_str != nullptr) {
	username = *user_str;
	password = *pass_str;
	}
	} else {
	// Openbmc appears to push a data object that contains the same
	// keys (username and password), attempt to use that
	auto data_it = login_credentials.find("data");
	if (data_it != login_credentials.end()) {
	// Some apis produce an array of value ["username",
	// "password"]
	if (data_it->is_array()) {
	if (data_it->size() == 2) {
	nlohmann::json::iterator user_it2 = data_it->begin();
	nlohmann::json::iterator pass_it2 = data_it->begin() + 1;
	looks_like_ibm = true;
	if (user_it2 != data_it->end() &&
	pass_it2 != data_it->end()) {
	const std::string* user_str =
	user_it2->get_ptr<const std::string*>();
	const std::string* pass_str =
	pass_it2->get_ptr<const std::string*>();
	if (user_str != nullptr && pass_str != nullptr) {
	username = *user_str;
	password = *pass_str;
	}
	}
	}

	} else if (data_it->is_object()) {
	nlohmann::json::iterator user_it2 = data_it->find("username");
	nlohmann::json::iterator pass_it2 = data_it->find("password");
	if (user_it2 != data_it->end() && pass_it2 != data_it->end()) {
	const std::string* user_str =
	user_it2->get_ptr<const std::string*>();
	const std::string* pass_str =
	pass_it2->get_ptr<const std::string*>();
	if (user_str != nullptr && pass_str != nullptr) {
	username = *user_str;
	password = *pass_str;
	}
	}
	}
	}
	}
	} else {
	// check if auth was provided as a headers
	username = req.get_header_value("username");
	password = req.get_header_value("password");
	}

	if (!username.empty() && !password.empty()) {
	if (!pam_authenticate_user(username, password)) {
	res.result(boost::beast::http::status::unauthorized);
	} else {
	auto session =
	PersistentData::session_store->generate_user_session(username);

	if (looks_like_ibm) {
	// IBM requires a very specific login structure, and doesn't
	// actually look at the status code. TODO(ed).... Fix that
	// upstream
	res.json_value = {
	{"data", "User '" + std::string(username) + "' logged in"},
	{"message", "200 OK"},
	{"status", "ok"}};

	// Hack alert. Boost beast by default doesn't let you declare
	// multiple headers of the same name, and in most cases this is
	// fine. Unfortunately here we need to set the Session cookie,
	// which requires the httpOnly attribute, as well as the XSRF
	// cookie, which requires it to not have an httpOnly attribute.
	// To get the behavior we want, we simply inject the second
	// "set-cookie" string into the value header, and get the result
	// we want, even though we are technicaly declaring two headers
	// here.
	res.add_header("Set-Cookie",
	"XSRF-TOKEN=" + session->csrf_token +
	"; Secure\r\nSet-Cookie: SESSION=" +
	session->session_token + "; Secure; HttpOnly");
	} else {
	// if content type is json, assume json token
	res.json_value = {{"token", session->session_token}};
	}
	}

	} else {
	res.result(boost::beast::http::status::bad_request);
	}
	res.end();
	});

	CROW_ROUTE(app, "/logout")
	.methods("POST"_method)(
	[&](const crow::request& req, crow::response& res) {
	auto& session =
	app.template get_context<TokenAuthorization::Middleware>(req)
	.session;
	if (session != nullptr) {
	PersistentData::session_store->remove_session(session);
	}
	res.end();
	return;

	});
	}
	} // namespace TokenAuthorization
	} // namespace crow