xref: /openbmc/bmcweb/include/authentication.hpp (revision a529a6aa)
1 #pragma once
2 
3 #include "cookies.hpp"
4 #include "forward_unauthorized.hpp"
5 #include "http_request.hpp"
6 #include "http_response.hpp"
7 #include "http_utility.hpp"
8 #include "pam_authenticate.hpp"
9 #include "webroutes.hpp"
10 
11 #include <boost/container/flat_set.hpp>
12 
13 #include <random>
14 #include <utility>
15 
16 namespace crow
17 {
18 
19 namespace authentication
20 {
21 
22 inline std::shared_ptr<persistent_data::UserSession>
23     performBasicAuth(const boost::asio::ip::address& clientIp,
24                      std::string_view authHeader)
25 {
26     BMCWEB_LOG_DEBUG("[AuthMiddleware] Basic authentication");
27 
28     if (!authHeader.starts_with("Basic "))
29     {
30         return nullptr;
31     }
32 
33     std::string_view param = authHeader.substr(strlen("Basic "));
34     std::string authData;
35 
36     if (!crow::utility::base64Decode(param, authData))
37     {
38         return nullptr;
39     }
40     std::size_t separator = authData.find(':');
41     if (separator == std::string::npos)
42     {
43         return nullptr;
44     }
45 
46     std::string user = authData.substr(0, separator);
47     separator += 1;
48     if (separator > authData.size())
49     {
50         return nullptr;
51     }
52     std::string pass = authData.substr(separator);
53 
54     BMCWEB_LOG_DEBUG("[AuthMiddleware] Authenticating user: {}", user);
55     BMCWEB_LOG_DEBUG("[AuthMiddleware] User IPAddress: {}",
56                      clientIp.to_string());
57 
58     int pamrc = pamAuthenticateUser(user, pass);
59     bool isConfigureSelfOnly = pamrc == PAM_NEW_AUTHTOK_REQD;
60     if ((pamrc != PAM_SUCCESS) && !isConfigureSelfOnly)
61     {
62         return nullptr;
63     }
64 
65     // Attempt to locate an existing Basic Auth session from the same ip address
66     // and user
67     for (auto& session :
68          persistent_data::SessionStore::getInstance().getSessions())
69     {
70         if (session->sessionType != persistent_data::SessionType::Basic)
71         {
72             continue;
73         }
74         if (session->clientIp != redfish::ip_util::toString(clientIp))
75         {
76             continue;
77         }
78         if (session->username != user)
79         {
80             continue;
81         }
82         return session;
83     }
84 
85     return persistent_data::SessionStore::getInstance().generateUserSession(
86         user, clientIp, std::nullopt, persistent_data::SessionType::Basic,
87         isConfigureSelfOnly);
88 }
89 
90 inline std::shared_ptr<persistent_data::UserSession>
91     performTokenAuth(std::string_view authHeader)
92 {
93     BMCWEB_LOG_DEBUG("[AuthMiddleware] Token authentication");
94     if (!authHeader.starts_with("Token "))
95     {
96         return nullptr;
97     }
98     std::string_view token = authHeader.substr(strlen("Token "));
99     auto sessionOut =
100         persistent_data::SessionStore::getInstance().loginSessionByToken(token);
101     return sessionOut;
102 }
103 
104 inline std::shared_ptr<persistent_data::UserSession>
105     performXtokenAuth(const boost::beast::http::header<true>& reqHeader)
106 {
107     BMCWEB_LOG_DEBUG("[AuthMiddleware] X-Auth-Token authentication");
108 
109     std::string_view token = reqHeader["X-Auth-Token"];
110     if (token.empty())
111     {
112         return nullptr;
113     }
114     auto sessionOut =
115         persistent_data::SessionStore::getInstance().loginSessionByToken(token);
116     return sessionOut;
117 }
118 
119 inline std::shared_ptr<persistent_data::UserSession>
120     performCookieAuth(boost::beast::http::verb method [[maybe_unused]],
121                       const boost::beast::http::header<true>& reqHeader)
122 {
123     using headers = boost::beast::http::header<true>;
124     std::pair<headers::const_iterator, headers::const_iterator> cookies =
125         reqHeader.equal_range(boost::beast::http::field::cookie);
126 
127     for (auto it = cookies.first; it != cookies.second; it++)
128     {
129         std::string_view cookieValue = it->value();
130         BMCWEB_LOG_DEBUG("Checking cookie {}", cookieValue);
131         auto startIndex = cookieValue.find("SESSION=");
132         if (startIndex == std::string::npos)
133         {
134             BMCWEB_LOG_DEBUG(
135                 "Cookie was present, but didn't look like a session {}",
136                 cookieValue);
137             continue;
138         }
139         startIndex += sizeof("SESSION=") - 1;
140         auto endIndex = cookieValue.find(';', startIndex);
141         if (endIndex == std::string::npos)
142         {
143             endIndex = cookieValue.size();
144         }
145         std::string_view authKey = cookieValue.substr(startIndex,
146                                                       endIndex - startIndex);
147 
148         std::shared_ptr<persistent_data::UserSession> sessionOut =
149             persistent_data::SessionStore::getInstance().loginSessionByToken(
150                 authKey);
151         if (sessionOut == nullptr)
152         {
153             return nullptr;
154         }
155         sessionOut->cookieAuth = true;
156 
157         if constexpr (!BMCWEB_INSECURE_DISABLE_CSRF)
158         {
159             // RFC7231 defines methods that need csrf protection
160             if (method != boost::beast::http::verb::get)
161             {
162                 std::string_view csrf = reqHeader["X-XSRF-TOKEN"];
163                 // Make sure both tokens are filled
164                 if (csrf.empty() || sessionOut->csrfToken.empty())
165                 {
166                     return nullptr;
167                 }
168 
169                 if (csrf.size() != persistent_data::sessionTokenSize)
170                 {
171                     return nullptr;
172                 }
173                 // Reject if csrf token not available
174                 if (!crow::utility::constantTimeStringCompare(
175                         csrf, sessionOut->csrfToken))
176                 {
177                     return nullptr;
178                 }
179             }
180         }
181         return sessionOut;
182     }
183     return nullptr;
184 }
185 
186 inline std::shared_ptr<persistent_data::UserSession>
187     performTLSAuth(Response& res,
188                    const std::shared_ptr<persistent_data::UserSession>& session)
189 {
190     if (session != nullptr)
191     {
192         res.addHeader(boost::beast::http::field::set_cookie,
193                       "IsAuthenticated=true; Secure");
194         BMCWEB_LOG_DEBUG(
195             " TLS session: {} with cookie will be used for this request.",
196             session->uniqueId);
197     }
198 
199     return session;
200 }
201 
202 // checks if request can be forwarded without authentication
203 inline bool isOnAllowlist(std::string_view url, boost::beast::http::verb method)
204 {
205     // Handle the case where the router registers routes as both ending with /
206     // and not.
207     if (url.ends_with('/') && url != "/")
208     {
209         url.remove_suffix(1);
210     }
211     if (boost::beast::http::verb::get == method)
212     {
213         if ((url == "/redfish") ||          //
214             (url == "/redfish/v1") ||       //
215             (url == "/redfish/v1/odata") || //
216             (url == "/redfish/v1/$metadata"))
217         {
218             return true;
219         }
220         if (crow::webroutes::routes.find(std::string(url)) !=
221             crow::webroutes::routes.end())
222         {
223             return true;
224         }
225     }
226 
227     // it's allowed to POST on session collection & login without
228     // authentication
229     if (boost::beast::http::verb::post == method)
230     {
231         if ((url == "/redfish/v1/SessionService/Sessions") ||
232             (url == "/redfish/v1/SessionService/Sessions/Members") ||
233             (url == "/login"))
234         {
235             return true;
236         }
237     }
238 
239     return false;
240 }
241 
242 inline std::shared_ptr<persistent_data::UserSession> authenticate(
243     const boost::asio::ip::address& ipAddress [[maybe_unused]],
244     Response& res [[maybe_unused]],
245     boost::beast::http::verb method [[maybe_unused]],
246     const boost::beast::http::header<true>& reqHeader,
247     [[maybe_unused]] const std::shared_ptr<persistent_data::UserSession>&
248         session)
249 {
250     const persistent_data::AuthConfigMethods& authMethodsConfig =
251         persistent_data::SessionStore::getInstance().getAuthMethodsConfig();
252 
253     std::shared_ptr<persistent_data::UserSession> sessionOut = nullptr;
254     if constexpr (BMCWEB_MUTUAL_TLS_AUTH)
255     {
256         if (authMethodsConfig.tls)
257         {
258             sessionOut = performTLSAuth(res, session);
259         }
260     }
261     if constexpr (BMCWEB_XTOKEN_AUTH)
262     {
263         if (sessionOut == nullptr && authMethodsConfig.xtoken)
264         {
265             sessionOut = performXtokenAuth(reqHeader);
266         }
267     }
268     if constexpr (BMCWEB_COOKIE_AUTH)
269     {
270         if (sessionOut == nullptr && authMethodsConfig.cookie)
271         {
272             sessionOut = performCookieAuth(method, reqHeader);
273         }
274     }
275     std::string_view authHeader = reqHeader["Authorization"];
276     BMCWEB_LOG_DEBUG("authHeader={}", authHeader);
277     if constexpr (BMCWEB_SESSION_AUTH)
278     {
279         if (sessionOut == nullptr && authMethodsConfig.sessionToken)
280         {
281             sessionOut = performTokenAuth(authHeader);
282         }
283     }
284     if constexpr (BMCWEB_BASIC_AUTH)
285     {
286         if (sessionOut == nullptr && authMethodsConfig.basic)
287         {
288             sessionOut = performBasicAuth(ipAddress, authHeader);
289         }
290     }
291     if (sessionOut != nullptr)
292     {
293         return sessionOut;
294     }
295 
296     return nullptr;
297 }
298 
299 } // namespace authentication
300 } // namespace crow
301