From 604fa651fcc14f893c96b8280928dca3fd9438e7 Mon Sep 17 00:00:00 2001
From: Jeidnx <jeidnx@domainhier.de>
Date: Sun, 18 Jun 2023 18:28:18 +0200
Subject: [PATCH 01/13] Implement oidc

---
 build.gradle                                  |   1 +
 config.properties                             |   6 ++
 .../java/me/kavin/piped/consts/Constants.java |  26 +++++
 .../me/kavin/piped/server/ServerLauncher.java | 101 ++++++++++++++++++
 .../server/handlers/auth/UserHandlers.java    |  38 ++++++-
 .../kavin/piped/utils/obj/OidcProvider.java   |  25 +++++
 .../me/kavin/piped/utils/obj/db/User.java     |   2 +-
 7 files changed, 195 insertions(+), 4 deletions(-)
 create mode 100644 src/main/java/me/kavin/piped/utils/obj/OidcProvider.java

diff --git a/build.gradle b/build.gradle
index ad13d64c..a59c346a 100644
--- a/build.gradle
+++ b/build.gradle
@@ -42,6 +42,7 @@ dependencies {
     implementation 'io.sentry:sentry:6.23.0'
     implementation 'rocks.kavin:reqwest4j:1.0.4'
     implementation 'io.minio:minio:8.5.3'
+    implementation 'com.nimbusds:oauth2-oidc-sdk:10.9.1'
 }
 
 shadowJar {
diff --git a/config.properties b/config.properties
index 5b147b8d..bd6efcb3 100644
--- a/config.properties
+++ b/config.properties
@@ -79,3 +79,9 @@ hibernate.connection.password:changeme
 # Frontend configuration
 #frontend.statusPageUrl:https://kavin.rocks
 #frontend.donationUrl:https://kavin.rocks
+
+# Oidc configuration
+#oidc.provider.INSERT_HERE.name:INSERT_HERE
+#oidc.provider.INSERT_HERE.clientId:INSERT_HERE
+#oidc.provider.INSERT_HERE.clientSecret:INSERT_HERE
+#oidc.provider.INSERT_HERE.authUrl:INSERT_HERE
diff --git a/src/main/java/me/kavin/piped/consts/Constants.java b/src/main/java/me/kavin/piped/consts/Constants.java
index 478b99e5..ef2fd829 100644
--- a/src/main/java/me/kavin/piped/consts/Constants.java
+++ b/src/main/java/me/kavin/piped/consts/Constants.java
@@ -3,12 +3,14 @@
 import com.fasterxml.jackson.databind.DeserializationFeature;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.json.JsonMapper;
+import com.fasterxml.jackson.databind.node.ArrayNode;
 import com.fasterxml.jackson.databind.node.JsonNodeFactory;
 import com.fasterxml.jackson.databind.node.ObjectNode;
 import io.minio.MinioClient;
 import it.unimi.dsi.fastutil.objects.Object2ObjectOpenHashMap;
 import me.kavin.piped.utils.PageMixin;
 import me.kavin.piped.utils.RequestUtils;
+import me.kavin.piped.utils.obj.OidcProvider;
 import me.kavin.piped.utils.resp.ListLinkHandlerMixin;
 import okhttp3.OkHttpClient;
 import okhttp3.brotli.BrotliInterceptor;
@@ -24,6 +26,7 @@
 import java.io.FileReader;
 import java.net.InetSocketAddress;
 import java.net.ProxySelector;
+import java.util.LinkedList;
 import java.util.List;
 import java.util.Properties;
 import java.util.regex.Pattern;
@@ -99,6 +102,7 @@ public class Constants {
     public static final String YOUTUBE_COUNTRY;
 
     public static final String VERSION;
+    public static final LinkedList<OidcProvider> OIDC_PROVIDERS;
 
     public static final ObjectMapper mapper = JsonMapper.builder()
             .addMixIn(Page.class, PageMixin.class)
@@ -162,12 +166,34 @@ public class Constants {
             MATRIX_SERVER = getProperty(prop, "MATRIX_SERVER", "https://matrix-client.matrix.org");
             MATRIX_TOKEN = getProperty(prop, "MATRIX_TOKEN");
             GEO_RESTRICTION_CHECKER_URL = getProperty(prop, "GEO_RESTRICTION_CHECKER_URL");
+
+            OIDC_PROVIDERS = new LinkedList<>();
+            ArrayNode providerNames = frontendProperties.putArray("oidcProviders");
             prop.forEach((_key, _value) -> {
                 String key = String.valueOf(_key), value = String.valueOf(_value);
                 if (key.startsWith("hibernate"))
                     hibernateProperties.put(key, value);
                 else if (key.startsWith("frontend."))
                     frontendProperties.put(StringUtils.substringAfter(key, "frontend."), value);
+                else if (key.startsWith("oidc.provider")) {
+                   String[] split = key.split("\\.");
+                   if (split.length != 4 || !split[3].equals("name")) return;
+
+                   try {
+                       OIDC_PROVIDERS.add(new OidcProvider(
+                                value,
+                                getProperty(prop, "oidc.provider." + value + ".clientId"),
+                                getProperty(prop, "oidc.provider." + value + ".clientSecret"),
+                                getProperty(prop, "oidc.provider." + value + ".authUrl"),
+                                getProperty(prop, "oidc.provider." + value + ".tokenUrl"),
+                                getProperty(prop, "oidc.provider." + value + ".userinfoUrl")
+                        ));
+                    } catch (Exception e) {
+                        System.err.println("Error while getting properties for oidc provider '" + value + "'");
+                        throw new RuntimeException(e);
+                    }
+                    providerNames.add(value);
+                }
             });
             frontendProperties.put("imageProxyUrl", IMAGE_PROXY_PART);
             frontendProperties.putArray("countries").addAll(
diff --git a/src/main/java/me/kavin/piped/server/ServerLauncher.java b/src/main/java/me/kavin/piped/server/ServerLauncher.java
index 44e83ada..6a860fc0 100644
--- a/src/main/java/me/kavin/piped/server/ServerLauncher.java
+++ b/src/main/java/me/kavin/piped/server/ServerLauncher.java
@@ -2,6 +2,9 @@
 
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.JsonNode;
+import com.nimbusds.oauth2.sdk.auth.ClientAuthentication;
+import com.nimbusds.oauth2.sdk.auth.ClientSecretBasic;
+import com.nimbusds.openid.connect.sdk.claims.UserInfo;
 import com.rometools.rome.feed.synd.SyndFeed;
 import com.rometools.rome.io.SyndFeedInput;
 import io.activej.config.Config;
@@ -19,7 +22,9 @@
 import me.kavin.piped.server.handlers.auth.StorageHandlers;
 import me.kavin.piped.server.handlers.auth.UserHandlers;
 import me.kavin.piped.utils.*;
+import me.kavin.piped.utils.ErrorResponse;
 import me.kavin.piped.utils.obj.MatrixHelper;
+import me.kavin.piped.utils.obj.OidcProvider;
 import me.kavin.piped.utils.obj.federation.FederatedVideoInfo;
 import me.kavin.piped.utils.resp.*;
 import org.apache.commons.lang3.StringUtils;
@@ -30,12 +35,18 @@
 import org.schabi.newpipe.extractor.exceptions.ParsingException;
 import org.schabi.newpipe.extractor.localization.DateWrapper;
 import org.xml.sax.InputSource;
+import com.nimbusds.oauth2.sdk.*;
+import com.nimbusds.openid.connect.sdk.*;
+import com.nimbusds.oauth2.sdk.id.*;
 
 import java.io.ByteArrayInputStream;
 import java.net.InetSocketAddress;
+import java.net.URI;
+import java.util.LinkedList;
 import java.util.Objects;
 import java.util.concurrent.Executor;
 import java.util.concurrent.TimeUnit;
+import java.util.regex.Pattern;
 
 import static io.activej.config.converter.ConfigConverters.ofInetSocketAddress;
 import static io.activej.http.HttpHeaders.*;
@@ -293,6 +304,88 @@ AsyncServlet mainServlet(Executor executor) {
                                 LoginRequest.class);
                         return getJsonResponse(UserHandlers.registerResponse(body.username, body.password),
                                 "private");
+                    } catch (Exception e) {
+                        return getErrorResponse(e, request.getPath());
+                    }
+                })).map(GET, "/oidc/:provider/:function", AsyncServlet.ofBlocking(executor, request -> {
+                    try {
+                        String function = request.getPathParameter("function");
+
+                        OidcProvider provider = findOidcProvider(request.getPathParameter("provider"), Constants.OIDC_PROVIDERS);
+                        if(provider == null)
+                            return HttpResponse.ofCode(500).withHtml("Can't find the provider on the server.");
+
+                        URI callback = new URI(Constants.PUBLIC_URL + "/oidc/" + provider.name + "/callback");
+
+                        switch (function) {
+                            case "login" -> {
+
+                                State state = new State();
+                                Nonce nonce = new Nonce();
+
+                                AuthenticationRequest oidcRequest = new AuthenticationRequest.Builder(
+                                        new ResponseType("code"),
+                                        new Scope("openid"),
+                                        provider.clientID,
+                                        callback)
+                                        .endpointURI(provider.authUri)
+                                        .state(state)
+                                        .nonce(nonce)
+                                        .build();
+
+                                return HttpResponse.redirect302(oidcRequest.toURI().toString());
+                            }
+                            case "callback" -> {
+                                ClientAuthentication clientAuth = new ClientSecretBasic(provider.clientID, provider.clientSecret);
+
+                                AuthenticationResponse response = AuthenticationResponseParser.parse(
+                                        URI.create(request.getFullUrl())
+                                );
+
+                                if (response instanceof AuthenticationErrorResponse) {
+                                    // The OpenID provider returned an error
+                                    System.err.println(response.toErrorResponse().getErrorObject());
+                                    return HttpResponse.ofCode(500).withHtml("OpenID provider returned an error:\n\n" + response.toErrorResponse().getErrorObject().toString());
+                                }
+                                AuthenticationSuccessResponse sr = response.toSuccessResponse();
+
+                                AuthorizationCode code = sr.getAuthorizationCode();
+                                AuthorizationGrant codeGrant = new AuthorizationCodeGrant(
+                                        code, callback
+                                );
+
+                                TokenRequest tr = new TokenRequest(provider.tokenUri, clientAuth, codeGrant);
+                                TokenResponse tokenResponse = OIDCTokenResponseParser.parse(tr.toHTTPRequest().send());
+
+                                if (! tokenResponse.indicatesSuccess()) {
+                                    TokenErrorResponse errorResponse = tokenResponse.toErrorResponse();
+                                    return HttpResponse.ofCode(500).withHtml("Failure while trying to request token:\n\n" + errorResponse.getErrorObject().getDescription());
+                                }
+
+                                OIDCTokenResponse successResponse = (OIDCTokenResponse)tokenResponse.toSuccessResponse();
+
+
+                                UserInfoRequest ur = new UserInfoRequest(provider.userinfoUri, successResponse.getOIDCTokens().getBearerAccessToken());
+                                UserInfoResponse userInfoResponse = UserInfoResponse.parse(ur.toHTTPRequest().send());
+
+                                if (! userInfoResponse.indicatesSuccess()) {
+                                    System.out.println(userInfoResponse.toErrorResponse().getErrorObject().getCode());
+                                    System.out.println(userInfoResponse.toErrorResponse().getErrorObject().getDescription());
+                                    return HttpResponse.ofCode(500).withHtml("Failed to query userInfo:\n\n" + userInfoResponse.toErrorResponse().getErrorObject().getDescription());
+                                }
+
+                                UserInfo userInfo = userInfoResponse.toSuccessResponse().getUserInfo();
+
+                                String sessionId = UserHandlers.oidcCallbackResponse(provider.name, userInfo.getSubject().toString());
+
+                                return HttpResponse.redirect302(Constants.FRONTEND_URL + "/login?session=" + sessionId);
+                            }
+                            default -> {
+                                return HttpResponse.ofCode(500).withHtml("Invalid function `" + function + "`.");
+                            }
+                        }
+
+
                     } catch (Exception e) {
                         return getErrorResponse(e, request.getPath());
                     }
@@ -542,6 +635,14 @@ AsyncServlet mainServlet(Executor executor) {
         return new CustomServletDecorator(router);
     }
 
+    private static OidcProvider findOidcProvider(String provider, LinkedList<OidcProvider> list){
+        for(int i = 0; i < list.size(); i++) {
+            OidcProvider curr = list.get(i);
+            if(curr == null || !curr.name.equals(provider)) continue;
+            return curr;
+        }
+        return null;
+    }
     private static String[] getArray(String s) {
 
         if (s == null) {
diff --git a/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java b/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java
index ad36481f..1c7c21c5 100644
--- a/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java
+++ b/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java
@@ -107,11 +107,36 @@ public static byte[] loginResponse(String user, String pass)
             return null;
         }
     }
+    public static String oidcCallbackResponse(String provider, String uid) {
+        try (Session s = DatabaseSessionFactory.createSession()) {
+                String dbName = provider + "-" + uid;
+                System.out.println(dbName); //TODO:
+                CriteriaBuilder cb = s.getCriteriaBuilder();
+                CriteriaQuery<User> cr = cb.createQuery(User.class);
+                Root<User> root = cr.from(User.class);
+                cr.select(root).where(root.get("username").in(
+                        dbName
+                ));
 
-    public static byte[] deleteUserResponse(String session, String pass) throws IOException {
+                User dbuser = s.createQuery(cr).uniqueResult();
+
+                if (dbuser == null) {
+                        User newuser = new User(dbName, "", Set.of());
+
+                        var tr = s.beginTransaction();
+                        s.persist(newuser);
+                        tr.commit();
+
+
+                        return newuser.getSessionId();
+                }
+                return dbuser.getSessionId();
+            }
 
-        if (StringUtils.isBlank(session) || StringUtils.isBlank(pass))
-            ExceptionHandler.throwErrorResponse(new InvalidRequestResponse("session and password are required parameters"));
+    }
+    public static byte[] deleteUserResponse(String session, String pass) throws IOException {
+        if (StringUtils.isBlank(session))
+            ExceptionHandler.throwErrorResponse(new InvalidRequestResponse("session is a required parameter"));
 
         try (Session s = DatabaseSessionFactory.createSession()) {
             User user = DatabaseHelper.getUserFromSession(session);
@@ -121,6 +146,13 @@ public static byte[] deleteUserResponse(String session, String pass) throws IOEx
 
             String hash = user.getPassword();
 
+            if (hash.equals("")) {
+                //TODO: Authorize against oidc provider before deletion
+                var tr = s.beginTransaction();
+                s.remove(user);
+                tr.commit();
+                return mapper.writeValueAsBytes(new DeleteUserResponse(user.getUsername()));
+            }
             if (!hashMatch(hash, pass))
                 ExceptionHandler.throwErrorResponse(new IncorrectCredentialsResponse());
 
diff --git a/src/main/java/me/kavin/piped/utils/obj/OidcProvider.java b/src/main/java/me/kavin/piped/utils/obj/OidcProvider.java
new file mode 100644
index 00000000..a869c2a1
--- /dev/null
+++ b/src/main/java/me/kavin/piped/utils/obj/OidcProvider.java
@@ -0,0 +1,25 @@
+package me.kavin.piped.utils.obj;
+
+import com.nimbusds.oauth2.sdk.auth.Secret;
+import com.nimbusds.oauth2.sdk.id.ClientID;
+
+import java.net.URI;
+import java.net.URISyntaxException;
+
+public class OidcProvider {
+    public String name;
+    public ClientID clientID;
+    public Secret clientSecret;
+    public URI authUri;
+    public URI tokenUri;
+    public URI userinfoUri;
+
+    public OidcProvider(String name, String clientID, String clientSecret, String authUri, String tokenUri, String userinfoUri) throws URISyntaxException {
+        this.name = name;
+        this.clientID = new ClientID(clientID);
+        this.clientSecret = new Secret(clientSecret);
+        this.authUri = new URI(authUri);
+        this.tokenUri = new URI(tokenUri);
+        this.userinfoUri = new URI(userinfoUri);
+    }
+}
diff --git a/src/main/java/me/kavin/piped/utils/obj/db/User.java b/src/main/java/me/kavin/piped/utils/obj/db/User.java
index fe3ceb4b..1bf1b42b 100644
--- a/src/main/java/me/kavin/piped/utils/obj/db/User.java
+++ b/src/main/java/me/kavin/piped/utils/obj/db/User.java
@@ -20,7 +20,7 @@ public class User implements Serializable {
     @Column(name = "id")
     private long id;
 
-    @Column(name = "username", unique = true, length = 24)
+    @Column(name = "username", unique = true, length = 32)
     private String username;
 
     @Column(name = "password", columnDefinition = "text")

From 375ee585c13eaa9a036061dcec1b9d15e872c89c Mon Sep 17 00:00:00 2001
From: Jeidnx <jeidnx@domainhier.de>
Date: Mon, 19 Jun 2023 13:11:20 +0200
Subject: [PATCH 02/13] Better Error handling for oidc config

---
 config.properties                             |  4 +-
 .../java/me/kavin/piped/consts/Constants.java | 39 ++++++++++---------
 .../kavin/piped/utils/obj/OidcProvider.java   | 13 +++++--
 3 files changed, 33 insertions(+), 23 deletions(-)

diff --git a/config.properties b/config.properties
index bd6efcb3..916cffbd 100644
--- a/config.properties
+++ b/config.properties
@@ -84,4 +84,6 @@ hibernate.connection.password:changeme
 #oidc.provider.INSERT_HERE.name:INSERT_HERE
 #oidc.provider.INSERT_HERE.clientId:INSERT_HERE
 #oidc.provider.INSERT_HERE.clientSecret:INSERT_HERE
-#oidc.provider.INSERT_HERE.authUrl:INSERT_HERE
+#oidc.provider.INSERT_HERE.authUri:INSERT_HERE
+#oidc.provider.INSERT_HERE.tokenUri:INSERT_HERE
+#oidc.provider.INSERT_HERE.userinfoUri:INSERT_HERE
\ No newline at end of file
diff --git a/src/main/java/me/kavin/piped/consts/Constants.java b/src/main/java/me/kavin/piped/consts/Constants.java
index ef2fd829..d8586be0 100644
--- a/src/main/java/me/kavin/piped/consts/Constants.java
+++ b/src/main/java/me/kavin/piped/consts/Constants.java
@@ -26,7 +26,7 @@
 import java.io.FileReader;
 import java.net.InetSocketAddress;
 import java.net.ProxySelector;
-import java.util.LinkedList;
+import java.util.ArrayList;
 import java.util.List;
 import java.util.Properties;
 import java.util.regex.Pattern;
@@ -102,7 +102,7 @@ public class Constants {
     public static final String YOUTUBE_COUNTRY;
 
     public static final String VERSION;
-    public static final LinkedList<OidcProvider> OIDC_PROVIDERS;
+    public static final ArrayList<OidcProvider> OIDC_PROVIDERS;
 
     public static final ObjectMapper mapper = JsonMapper.builder()
             .addMixIn(Page.class, PageMixin.class)
@@ -167,7 +167,7 @@ public class Constants {
             MATRIX_TOKEN = getProperty(prop, "MATRIX_TOKEN");
             GEO_RESTRICTION_CHECKER_URL = getProperty(prop, "GEO_RESTRICTION_CHECKER_URL");
 
-            OIDC_PROVIDERS = new LinkedList<>();
+            OIDC_PROVIDERS = new ArrayList<>();
             ArrayNode providerNames = frontendProperties.putArray("oidcProviders");
             prop.forEach((_key, _value) -> {
                 String key = String.valueOf(_key), value = String.valueOf(_value);
@@ -178,21 +178,15 @@ else if (key.startsWith("frontend."))
                 else if (key.startsWith("oidc.provider")) {
                    String[] split = key.split("\\.");
                    if (split.length != 4 || !split[3].equals("name")) return;
-
-                   try {
-                       OIDC_PROVIDERS.add(new OidcProvider(
-                                value,
-                                getProperty(prop, "oidc.provider." + value + ".clientId"),
-                                getProperty(prop, "oidc.provider." + value + ".clientSecret"),
-                                getProperty(prop, "oidc.provider." + value + ".authUrl"),
-                                getProperty(prop, "oidc.provider." + value + ".tokenUrl"),
-                                getProperty(prop, "oidc.provider." + value + ".userinfoUrl")
-                        ));
-                    } catch (Exception e) {
-                        System.err.println("Error while getting properties for oidc provider '" + value + "'");
-                        throw new RuntimeException(e);
-                    }
-                    providerNames.add(value);
+                   OIDC_PROVIDERS.add(new OidcProvider(
+                           value,
+                           getRequiredOidcProperty(prop, value, "clientId"),
+                           getRequiredOidcProperty(prop, value, "clientSecret"),
+                           getRequiredOidcProperty(prop, value, "authUri"),
+                           getRequiredOidcProperty(prop, value, "tokenUri"),
+                           getRequiredOidcProperty(prop, value, "userinfoUri"))
+                   );
+                   providerNames.add(value);
                 }
             });
             frontendProperties.put("imageProxyUrl", IMAGE_PROXY_PART);
@@ -256,4 +250,13 @@ private static String getProperty(final Properties prop, String key, String def)
 
         return prop.getProperty(key, def);
     }
+
+    private static String getRequiredOidcProperty(final Properties prop, String provider, String key) {
+        String value = getProperty(prop, "oidc.provider." + provider + "." + key);
+        if(value == null || value.equals("")){
+            System.err.println("Missing " + key + " for oidc provider '" + provider + "'");
+            System.exit(1);
+        }
+        return value;
+    }
 }
diff --git a/src/main/java/me/kavin/piped/utils/obj/OidcProvider.java b/src/main/java/me/kavin/piped/utils/obj/OidcProvider.java
index a869c2a1..79216ea5 100644
--- a/src/main/java/me/kavin/piped/utils/obj/OidcProvider.java
+++ b/src/main/java/me/kavin/piped/utils/obj/OidcProvider.java
@@ -14,12 +14,17 @@ public class OidcProvider {
     public URI tokenUri;
     public URI userinfoUri;
 
-    public OidcProvider(String name, String clientID, String clientSecret, String authUri, String tokenUri, String userinfoUri) throws URISyntaxException {
+    public OidcProvider(String name, String clientID, String clientSecret, String authUri, String tokenUri, String userinfoUri) {
         this.name = name;
         this.clientID = new ClientID(clientID);
         this.clientSecret = new Secret(clientSecret);
-        this.authUri = new URI(authUri);
-        this.tokenUri = new URI(tokenUri);
-        this.userinfoUri = new URI(userinfoUri);
+        try {
+            this.authUri = new URI(authUri);
+            this.tokenUri = new URI(tokenUri);
+            this.userinfoUri = new URI(userinfoUri);
+        } catch(URISyntaxException e) {
+            System.err.println("Malformed URI for oidc provider '" + name + "' found.");
+            System.exit(1);
+        }
     }
 }

From 143711cb2ae5b2dc771bb7db8b1d96580e7f8cc8 Mon Sep 17 00:00:00 2001
From: Jeidnx <jeidnx@domainhier.de>
Date: Mon, 19 Jun 2023 16:06:26 +0200
Subject: [PATCH 03/13] Save redirect in state

---
 .../me/kavin/piped/server/ServerLauncher.java    | 16 +++++++---------
 .../piped/server/handlers/auth/UserHandlers.java |  1 -
 2 files changed, 7 insertions(+), 10 deletions(-)

diff --git a/src/main/java/me/kavin/piped/server/ServerLauncher.java b/src/main/java/me/kavin/piped/server/ServerLauncher.java
index 6a860fc0..53b5403a 100644
--- a/src/main/java/me/kavin/piped/server/ServerLauncher.java
+++ b/src/main/java/me/kavin/piped/server/ServerLauncher.java
@@ -42,11 +42,9 @@
 import java.io.ByteArrayInputStream;
 import java.net.InetSocketAddress;
 import java.net.URI;
-import java.util.LinkedList;
 import java.util.Objects;
 import java.util.concurrent.Executor;
 import java.util.concurrent.TimeUnit;
-import java.util.regex.Pattern;
 
 import static io.activej.config.converter.ConfigConverters.ofInetSocketAddress;
 import static io.activej.http.HttpHeaders.*;
@@ -310,8 +308,7 @@ AsyncServlet mainServlet(Executor executor) {
                 })).map(GET, "/oidc/:provider/:function", AsyncServlet.ofBlocking(executor, request -> {
                     try {
                         String function = request.getPathParameter("function");
-
-                        OidcProvider provider = findOidcProvider(request.getPathParameter("provider"), Constants.OIDC_PROVIDERS);
+                        OidcProvider provider = getOidcProvider(request.getPathParameter("provider"));
                         if(provider == null)
                             return HttpResponse.ofCode(500).withHtml("Can't find the provider on the server.");
 
@@ -319,8 +316,9 @@ AsyncServlet mainServlet(Executor executor) {
 
                         switch (function) {
                             case "login" -> {
+                                String redirectUri = request.getQueryParameter("redirect");
 
-                                State state = new State();
+                                State state = new State(new Identifier(24) + "." + redirectUri);
                                 Nonce nonce = new Nonce();
 
                                 AuthenticationRequest oidcRequest = new AuthenticationRequest.Builder(
@@ -378,7 +376,7 @@ AsyncServlet mainServlet(Executor executor) {
 
                                 String sessionId = UserHandlers.oidcCallbackResponse(provider.name, userInfo.getSubject().toString());
 
-                                return HttpResponse.redirect302(Constants.FRONTEND_URL + "/login?session=" + sessionId);
+                                return HttpResponse.redirect302(sr.getState().toString().split("\\.", 2)[1] + "?session=" + sessionId);
                             }
                             default -> {
                                 return HttpResponse.ofCode(500).withHtml("Invalid function `" + function + "`.");
@@ -635,9 +633,9 @@ AsyncServlet mainServlet(Executor executor) {
         return new CustomServletDecorator(router);
     }
 
-    private static OidcProvider findOidcProvider(String provider, LinkedList<OidcProvider> list){
-        for(int i = 0; i < list.size(); i++) {
-            OidcProvider curr = list.get(i);
+    private static OidcProvider getOidcProvider(String provider){
+        for(int i = 0; i < Constants.OIDC_PROVIDERS.size(); i++) {
+            OidcProvider curr = Constants.OIDC_PROVIDERS.get(i);
             if(curr == null || !curr.name.equals(provider)) continue;
             return curr;
         }
diff --git a/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java b/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java
index 1c7c21c5..b783819b 100644
--- a/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java
+++ b/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java
@@ -110,7 +110,6 @@ public static byte[] loginResponse(String user, String pass)
     public static String oidcCallbackResponse(String provider, String uid) {
         try (Session s = DatabaseSessionFactory.createSession()) {
                 String dbName = provider + "-" + uid;
-                System.out.println(dbName); //TODO:
                 CriteriaBuilder cb = s.getCriteriaBuilder();
                 CriteriaQuery<User> cr = cb.createQuery(User.class);
                 Root<User> root = cr.from(User.class);

From 18d93177fbe8009a45379f67734bad6d5d284d45 Mon Sep 17 00:00:00 2001
From: Jeidnx <jeidnx@domainhier.de>
Date: Mon, 19 Jun 2023 16:50:20 +0200
Subject: [PATCH 04/13] Show warning message before oidc login

---
 src/main/java/me/kavin/piped/server/ServerLauncher.java | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/main/java/me/kavin/piped/server/ServerLauncher.java b/src/main/java/me/kavin/piped/server/ServerLauncher.java
index 53b5403a..d549b15b 100644
--- a/src/main/java/me/kavin/piped/server/ServerLauncher.java
+++ b/src/main/java/me/kavin/piped/server/ServerLauncher.java
@@ -331,7 +331,13 @@ AsyncServlet mainServlet(Executor executor) {
                                         .nonce(nonce)
                                         .build();
 
-                                return HttpResponse.redirect302(oidcRequest.toURI().toString());
+                                return HttpResponse.ok200().withHtml(
+                                        "<!DOCTYPE html><html style= \"color: white;background: #0f0f0f;\"><body>"
+                                                + "<h3>Warning:</h3> You are trying to give <pre style=\"font-size: 1.2rem;\">"
+                                                + redirectUri
+                                                + "</pre> access to your Piped account. If you wish to continue click <a style=\"text-decoration: underline;color: inherit;\"href=\""
+                                                + oidcRequest.toURI().toString()
+                                                + "\">here</a></body></html>");
                             }
                             case "callback" -> {
                                 ClientAuthentication clientAuth = new ClientSecretBasic(provider.clientID, provider.clientSecret);

From f4b9dffebe4a388c58dfe2e5f5277f4b81cad044 Mon Sep 17 00:00:00 2001
From: Jeidnx <jeidnx@domainhier.de>
Date: Tue, 27 Jun 2023 12:24:18 +0200
Subject: [PATCH 05/13] Only show warning when not redirecting to configured
 frontend

---
 src/main/java/me/kavin/piped/server/ServerLauncher.java | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/main/java/me/kavin/piped/server/ServerLauncher.java b/src/main/java/me/kavin/piped/server/ServerLauncher.java
index d549b15b..f88e7bc9 100644
--- a/src/main/java/me/kavin/piped/server/ServerLauncher.java
+++ b/src/main/java/me/kavin/piped/server/ServerLauncher.java
@@ -318,6 +318,9 @@ AsyncServlet mainServlet(Executor executor) {
                             case "login" -> {
                                 String redirectUri = request.getQueryParameter("redirect");
 
+                                if (redirectUri == null || redirectUri.equals("")) {
+                                    return HttpResponse.ofCode(400).withHtml("Missing redirect parameter");
+                                }
                                 State state = new State(new Identifier(24) + "." + redirectUri);
                                 Nonce nonce = new Nonce();
 
@@ -331,6 +334,9 @@ AsyncServlet mainServlet(Executor executor) {
                                         .nonce(nonce)
                                         .build();
 
+                                if(redirectUri.equals(Constants.FRONTEND_URL + "/login")) {
+                                    return HttpResponse.redirect302(oidcRequest.toURI().toString());
+                                }
                                 return HttpResponse.ok200().withHtml(
                                         "<!DOCTYPE html><html style= \"color: white;background: #0f0f0f;\"><body>"
                                                 + "<h3>Warning:</h3> You are trying to give <pre style=\"font-size: 1.2rem;\">"

From 847f80c0d43b8821bd5e955a824392f4f44cf478 Mon Sep 17 00:00:00 2001
From: Kavin <20838718+FireMasterK@users.noreply.github.com>
Date: Sat, 5 Aug 2023 16:53:38 +0100
Subject: [PATCH 06/13] Simplify config handling.

---
 .../java/me/kavin/piped/consts/Constants.java | 48 +++++++++++--------
 1 file changed, 28 insertions(+), 20 deletions(-)

diff --git a/src/main/java/me/kavin/piped/consts/Constants.java b/src/main/java/me/kavin/piped/consts/Constants.java
index 3340cc63..3b44b07b 100644
--- a/src/main/java/me/kavin/piped/consts/Constants.java
+++ b/src/main/java/me/kavin/piped/consts/Constants.java
@@ -8,6 +8,7 @@
 import com.fasterxml.jackson.databind.node.ObjectNode;
 import io.minio.MinioClient;
 import it.unimi.dsi.fastutil.objects.Object2ObjectOpenHashMap;
+import it.unimi.dsi.fastutil.objects.ObjectArrayList;
 import me.kavin.piped.utils.PageMixin;
 import me.kavin.piped.utils.RequestUtils;
 import me.kavin.piped.utils.obj.OidcProvider;
@@ -25,10 +26,8 @@
 
 import java.io.File;
 import java.io.FileReader;
-import java.net.InetSocketAddress;
-import java.net.ProxySelector;
-import java.util.ArrayList;
 import java.util.List;
+import java.util.Map;
 import java.util.Properties;
 import java.util.regex.Pattern;
 
@@ -103,7 +102,7 @@ public class Constants {
     public static final String YOUTUBE_COUNTRY;
 
     public static final String VERSION;
-    public static final ArrayList<OidcProvider> OIDC_PROVIDERS;
+    public static final List<OidcProvider> OIDC_PROVIDERS;
 
     public static final ObjectMapper mapper = JsonMapper.builder()
             .addMixIn(Page.class, PageMixin.class)
@@ -169,7 +168,9 @@ public class Constants {
             MATRIX_TOKEN = getProperty(prop, "MATRIX_TOKEN");
             GEO_RESTRICTION_CHECKER_URL = getProperty(prop, "GEO_RESTRICTION_CHECKER_URL");
 
-            OIDC_PROVIDERS = new ArrayList<>();
+            OIDC_PROVIDERS = new ObjectArrayList<>();
+
+            Map<String, Map<String, String>> oidcProviderConfig = new Object2ObjectOpenHashMap<>();
             ArrayNode providerNames = frontendProperties.putArray("oidcProviders");
             prop.forEach((_key, _value) -> {
                 String key = String.valueOf(_key), value = String.valueOf(_value);
@@ -178,19 +179,26 @@ public class Constants {
                 else if (key.startsWith("frontend."))
                     frontendProperties.put(StringUtils.substringAfter(key, "frontend."), value);
                 else if (key.startsWith("oidc.provider")) {
-                   String[] split = key.split("\\.");
-                   if (split.length != 4 || !split[3].equals("name")) return;
-                   OIDC_PROVIDERS.add(new OidcProvider(
-                           value,
-                           getRequiredOidcProperty(prop, value, "clientId"),
-                           getRequiredOidcProperty(prop, value, "clientSecret"),
-                           getRequiredOidcProperty(prop, value, "authUri"),
-                           getRequiredOidcProperty(prop, value, "tokenUri"),
-                           getRequiredOidcProperty(prop, value, "userinfoUri"))
-                   );
-                   providerNames.add(value);
+                    String[] split = key.split("\\.");
+                    if (split.length != 4) return;
+                    oidcProviderConfig
+                            .computeIfAbsent(split[2], k -> new Object2ObjectOpenHashMap<>())
+                            .put(split[3], value);
                 }
             });
+            oidcProviderConfig.forEach((provider, config) -> {
+                ObjectNode providerNode = frontendProperties.putObject(provider);
+                OIDC_PROVIDERS.add(new OidcProvider(
+                        getRequiredMapValue(config, "name"),
+                        getRequiredMapValue(config, "clientId"),
+                        getRequiredMapValue(config, "clientSecret"),
+                        getRequiredMapValue(config, "authUri"),
+                        getRequiredMapValue(config, "tokenUri"),
+                        getRequiredMapValue(config, "userinfoUri")
+                ));
+                providerNames.add(provider);
+                config.forEach(providerNode::put);
+            });
             frontendProperties.put("imageProxyUrl", IMAGE_PROXY_PART);
             frontendProperties.putArray("countries").addAll(
                     YOUTUBE_SERVICE.getSupportedCountries().stream().map(ContentCountry::getCountryCode)
@@ -247,10 +255,10 @@ private static String getProperty(final Properties prop, String key, String def)
         return prop.getProperty(key, def);
     }
 
-    private static String getRequiredOidcProperty(final Properties prop, String provider, String key) {
-        String value = getProperty(prop, "oidc.provider." + provider + "." + key);
-        if(value == null || value.equals("")){
-            System.err.println("Missing " + key + " for oidc provider '" + provider + "'");
+    private static String getRequiredMapValue(final Map<?, String> map, Object key) {
+        String value = map.get(key);
+        if (StringUtils.isBlank(value)) {
+            System.err.println("Missing '" + key + "' in sub-configuration");
             System.exit(1);
         }
         return value;

From 946ac458ed9abaa91e907a946509580ec8ec2dbf Mon Sep 17 00:00:00 2001
From: Kavin <20838718+FireMasterK@users.noreply.github.com>
Date: Sat, 5 Aug 2023 16:56:59 +0100
Subject: [PATCH 07/13] Add missing newline.

---
 config.properties | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/config.properties b/config.properties
index 498d9d05..71df0fb1 100644
--- a/config.properties
+++ b/config.properties
@@ -86,4 +86,4 @@ hibernate.connection.password:changeme
 #oidc.provider.INSERT_HERE.clientSecret:INSERT_HERE
 #oidc.provider.INSERT_HERE.authUri:INSERT_HERE
 #oidc.provider.INSERT_HERE.tokenUri:INSERT_HERE
-#oidc.provider.INSERT_HERE.userinfoUri:INSERT_HERE
\ No newline at end of file
+#oidc.provider.INSERT_HERE.userinfoUri:INSERT_HERE

From 0eb235180bdd0f844ba2cb443a67b740690288ce Mon Sep 17 00:00:00 2001
From: Kavin <20838718+FireMasterK@users.noreply.github.com>
Date: Sat, 5 Aug 2023 17:37:42 +0100
Subject: [PATCH 08/13] Format all code.

---
 .../me/kavin/piped/server/ServerLauncher.java | 30 ++++++++--------
 .../server/handlers/auth/UserHandlers.java    | 34 ++++++++++---------
 .../kavin/piped/utils/obj/OidcProvider.java   |  2 +-
 3 files changed, 35 insertions(+), 31 deletions(-)

diff --git a/src/main/java/me/kavin/piped/server/ServerLauncher.java b/src/main/java/me/kavin/piped/server/ServerLauncher.java
index a62b996d..676fc448 100644
--- a/src/main/java/me/kavin/piped/server/ServerLauncher.java
+++ b/src/main/java/me/kavin/piped/server/ServerLauncher.java
@@ -2,8 +2,12 @@
 
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.JsonNode;
+import com.nimbusds.oauth2.sdk.*;
 import com.nimbusds.oauth2.sdk.auth.ClientAuthentication;
 import com.nimbusds.oauth2.sdk.auth.ClientSecretBasic;
+import com.nimbusds.oauth2.sdk.id.Identifier;
+import com.nimbusds.oauth2.sdk.id.State;
+import com.nimbusds.openid.connect.sdk.*;
 import com.nimbusds.openid.connect.sdk.claims.UserInfo;
 import com.rometools.rome.feed.synd.SyndFeed;
 import com.rometools.rome.io.SyndFeedInput;
@@ -21,8 +25,8 @@
 import me.kavin.piped.server.handlers.auth.FeedHandlers;
 import me.kavin.piped.server.handlers.auth.StorageHandlers;
 import me.kavin.piped.server.handlers.auth.UserHandlers;
-import me.kavin.piped.utils.*;
 import me.kavin.piped.utils.ErrorResponse;
+import me.kavin.piped.utils.*;
 import me.kavin.piped.utils.obj.MatrixHelper;
 import me.kavin.piped.utils.obj.OidcProvider;
 import me.kavin.piped.utils.obj.federation.FederatedVideoInfo;
@@ -35,14 +39,10 @@
 import org.schabi.newpipe.extractor.exceptions.ParsingException;
 import org.schabi.newpipe.extractor.localization.DateWrapper;
 import org.xml.sax.InputSource;
-import com.nimbusds.oauth2.sdk.*;
-import com.nimbusds.openid.connect.sdk.*;
-import com.nimbusds.oauth2.sdk.id.*;
 
 import java.io.ByteArrayInputStream;
 import java.net.InetSocketAddress;
 import java.net.URI;
-import java.util.List;
 import java.util.Objects;
 import java.util.concurrent.Executor;
 import java.util.concurrent.TimeUnit;
@@ -330,7 +330,7 @@ AsyncServlet mainServlet(Executor executor) {
                     try {
                         String function = request.getPathParameter("function");
                         OidcProvider provider = getOidcProvider(request.getPathParameter("provider"));
-                        if(provider == null)
+                        if (provider == null)
                             return HttpResponse.ofCode(500).withHtml("Can't find the provider on the server.");
 
                         URI callback = new URI(Constants.PUBLIC_URL + "/oidc/" + provider.name + "/callback");
@@ -339,9 +339,10 @@ AsyncServlet mainServlet(Executor executor) {
                             case "login" -> {
                                 String redirectUri = request.getQueryParameter("redirect");
 
-                                if (redirectUri == null || redirectUri.equals("")) {
+                                if (StringUtils.isBlank(redirectUri)) {
                                     return HttpResponse.ofCode(400).withHtml("Missing redirect parameter");
                                 }
+
                                 State state = new State(new Identifier(24) + "." + redirectUri);
                                 Nonce nonce = new Nonce();
 
@@ -355,7 +356,7 @@ AsyncServlet mainServlet(Executor executor) {
                                         .nonce(nonce)
                                         .build();
 
-                                if(redirectUri.equals(Constants.FRONTEND_URL + "/login")) {
+                                if (redirectUri.equals(Constants.FRONTEND_URL + "/login")) {
                                     return HttpResponse.redirect302(oidcRequest.toURI().toString());
                                 }
                                 return HttpResponse.ok200().withHtml(
@@ -388,18 +389,18 @@ AsyncServlet mainServlet(Executor executor) {
                                 TokenRequest tr = new TokenRequest(provider.tokenUri, clientAuth, codeGrant);
                                 TokenResponse tokenResponse = OIDCTokenResponseParser.parse(tr.toHTTPRequest().send());
 
-                                if (! tokenResponse.indicatesSuccess()) {
+                                if (!tokenResponse.indicatesSuccess()) {
                                     TokenErrorResponse errorResponse = tokenResponse.toErrorResponse();
                                     return HttpResponse.ofCode(500).withHtml("Failure while trying to request token:\n\n" + errorResponse.getErrorObject().getDescription());
                                 }
 
-                                OIDCTokenResponse successResponse = (OIDCTokenResponse)tokenResponse.toSuccessResponse();
+                                OIDCTokenResponse successResponse = (OIDCTokenResponse) tokenResponse.toSuccessResponse();
 
 
                                 UserInfoRequest ur = new UserInfoRequest(provider.userinfoUri, successResponse.getOIDCTokens().getBearerAccessToken());
                                 UserInfoResponse userInfoResponse = UserInfoResponse.parse(ur.toHTTPRequest().send());
 
-                                if (! userInfoResponse.indicatesSuccess()) {
+                                if (!userInfoResponse.indicatesSuccess()) {
                                     System.out.println(userInfoResponse.toErrorResponse().getErrorObject().getCode());
                                     System.out.println(userInfoResponse.toErrorResponse().getErrorObject().getDescription());
                                     return HttpResponse.ofCode(500).withHtml("Failed to query userInfo:\n\n" + userInfoResponse.toErrorResponse().getErrorObject().getDescription());
@@ -666,14 +667,15 @@ AsyncServlet mainServlet(Executor executor) {
         return new CustomServletDecorator(router);
     }
 
-    private static OidcProvider getOidcProvider(String provider){
-        for(int i = 0; i < Constants.OIDC_PROVIDERS.size(); i++) {
+    private static OidcProvider getOidcProvider(String provider) {
+        for (int i = 0; i < Constants.OIDC_PROVIDERS.size(); i++) {
             OidcProvider curr = Constants.OIDC_PROVIDERS.get(i);
-            if(curr == null || !curr.name.equals(provider)) continue;
+            if (curr == null || !curr.name.equals(provider)) continue;
             return curr;
         }
         return null;
     }
+
     private static String[] getArray(String s) {
 
         if (s == null) {
diff --git a/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java b/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java
index 8788ce2a..7059bc29 100644
--- a/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java
+++ b/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java
@@ -108,32 +108,34 @@ public static byte[] loginResponse(String user, String pass)
             return null;
         }
     }
+
     public static String oidcCallbackResponse(String provider, String uid) {
         try (Session s = DatabaseSessionFactory.createSession()) {
-                String dbName = provider + "-" + uid;
-                CriteriaBuilder cb = s.getCriteriaBuilder();
-                CriteriaQuery<User> cr = cb.createQuery(User.class);
-                Root<User> root = cr.from(User.class);
-                cr.select(root).where(root.get("username").in(
-                        dbName
-                ));
+            String dbName = provider + "-" + uid;
+            CriteriaBuilder cb = s.getCriteriaBuilder();
+            CriteriaQuery<User> cr = cb.createQuery(User.class);
+            Root<User> root = cr.from(User.class);
+            cr.select(root).where(root.get("username").in(
+                    dbName
+            ));
 
-                User dbuser = s.createQuery(cr).uniqueResult();
+            User dbuser = s.createQuery(cr).uniqueResult();
 
-                if (dbuser == null) {
-                        User newuser = new User(dbName, "", Set.of());
+            if (dbuser == null) {
+                User newuser = new User(dbName, "", Set.of());
 
-                        var tr = s.beginTransaction();
-                        s.persist(newuser);
-                        tr.commit();
+                var tr = s.beginTransaction();
+                s.persist(newuser);
+                tr.commit();
 
 
-                        return newuser.getSessionId();
-                }
-                return dbuser.getSessionId();
+                return newuser.getSessionId();
             }
+            return dbuser.getSessionId();
+        }
 
     }
+
     public static byte[] deleteUserResponse(String session, String pass) throws IOException {
         if (StringUtils.isBlank(session))
             ExceptionHandler.throwErrorResponse(new InvalidRequestResponse("session is a required parameter"));
diff --git a/src/main/java/me/kavin/piped/utils/obj/OidcProvider.java b/src/main/java/me/kavin/piped/utils/obj/OidcProvider.java
index 79216ea5..aedce630 100644
--- a/src/main/java/me/kavin/piped/utils/obj/OidcProvider.java
+++ b/src/main/java/me/kavin/piped/utils/obj/OidcProvider.java
@@ -22,7 +22,7 @@ public OidcProvider(String name, String clientID, String clientSecret, String au
             this.authUri = new URI(authUri);
             this.tokenUri = new URI(tokenUri);
             this.userinfoUri = new URI(userinfoUri);
-        } catch(URISyntaxException e) {
+        } catch (URISyntaxException e) {
             System.err.println("Malformed URI for oidc provider '" + name + "' found.");
             System.exit(1);
         }

From e7f2187b47cbfbcab3cd4c1108e2dcd5446850a7 Mon Sep 17 00:00:00 2001
From: Jeidnx <jeidnx@domainhier.de>
Date: Wed, 25 Oct 2023 10:03:15 +0200
Subject: [PATCH 09/13] Implement account deletion and cleanup some code

---
 build.gradle                                  |   2 +-
 .../me/kavin/piped/server/ServerLauncher.java | 127 +++++++++++++-----
 .../server/handlers/auth/UserHandlers.java    |  45 ++++++-
 .../me/kavin/piped/utils/obj/OidcData.java    |  36 +++++
 4 files changed, 170 insertions(+), 40 deletions(-)
 create mode 100644 src/main/java/me/kavin/piped/utils/obj/OidcData.java

diff --git a/build.gradle b/build.gradle
index 3da01944..8d790511 100644
--- a/build.gradle
+++ b/build.gradle
@@ -18,7 +18,7 @@ dependencies {
     implementation 'org.bouncycastle:bcprov-jdk15on:1.70'
     implementation 'com.github.FireMasterK.NewPipeExtractor:NewPipeExtractor:48beff184a9792c4787cfa05fce577c3adf89f56'
     implementation 'com.github.FireMasterK:nanojson:9f4af3b739cc13f3d0d9d4b758bbe2b2ae7119d7'
-    implementation 'com.nimbusds:oauth2-oidc-sdk:11.5.0'
+    implementation 'com.nimbusds:oauth2-oidc-sdk:11.5'
     implementation 'com.fasterxml.jackson.core:jackson-core:2.15.2'
     implementation 'com.fasterxml.jackson.core:jackson-annotations:2.15.2'
     implementation 'com.fasterxml.jackson.core:jackson-databind:2.15.2'
diff --git a/src/main/java/me/kavin/piped/server/ServerLauncher.java b/src/main/java/me/kavin/piped/server/ServerLauncher.java
index a089b396..3394909b 100644
--- a/src/main/java/me/kavin/piped/server/ServerLauncher.java
+++ b/src/main/java/me/kavin/piped/server/ServerLauncher.java
@@ -2,10 +2,10 @@
 
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.JsonNode;
+import com.nimbusds.jwt.JWTClaimsSet;
 import com.nimbusds.oauth2.sdk.*;
 import com.nimbusds.oauth2.sdk.auth.ClientAuthentication;
 import com.nimbusds.oauth2.sdk.auth.ClientSecretBasic;
-import com.nimbusds.oauth2.sdk.id.Identifier;
 import com.nimbusds.oauth2.sdk.id.State;
 import com.nimbusds.openid.connect.sdk.*;
 import com.nimbusds.openid.connect.sdk.claims.UserInfo;
@@ -28,6 +28,7 @@
 import me.kavin.piped.utils.ErrorResponse;
 import me.kavin.piped.utils.*;
 import me.kavin.piped.utils.obj.MatrixHelper;
+import me.kavin.piped.utils.obj.OidcData;
 import me.kavin.piped.utils.obj.OidcProvider;
 import me.kavin.piped.utils.obj.federation.FederatedVideoInfo;
 import me.kavin.piped.utils.resp.*;
@@ -43,6 +44,8 @@
 import java.io.ByteArrayInputStream;
 import java.net.InetSocketAddress;
 import java.net.URI;
+import java.util.HashMap;
+import java.util.Map;
 import java.util.Objects;
 import java.util.concurrent.Executor;
 import java.util.concurrent.TimeUnit;
@@ -58,6 +61,7 @@ public class ServerLauncher extends MultithreadedHttpServerLauncher {
 
     private static final HttpHeader FILE_NAME = HttpHeaders.of("x-file-name");
     private static final HttpHeader LAST_ETAG = HttpHeaders.of("x-last-etag");
+    private static final Map<String, OidcData> PENDING_OIDC = new HashMap<>();
 
     @Provides
     Executor executor() {
@@ -285,7 +289,7 @@ AsyncServlet mainServlet(Executor executor) {
                         String function = request.getPathParameter("function");
                         OidcProvider provider = getOidcProvider(request.getPathParameter("provider"));
                         if (provider == null)
-                            return HttpResponse.ofCode(500).withHtml("Can't find the provider on the server.");
+                            return HttpResponse.ofCode(500).withHtml("Can't find the provider on the server");
 
                         URI callback = new URI(Constants.PUBLIC_URL + "/oidc/" + provider.name + "/callback");
 
@@ -294,62 +298,62 @@ AsyncServlet mainServlet(Executor executor) {
                                 String redirectUri = request.getQueryParameter("redirect");
 
                                 if (StringUtils.isBlank(redirectUri)) {
-                                    return HttpResponse.ofCode(400).withHtml("Missing redirect parameter");
+                                    return HttpResponse.ofCode(400).withHtml("redirect is a required parameter");
                                 }
 
-                                State state = new State(new Identifier(24) + "." + redirectUri);
-                                Nonce nonce = new Nonce();
+                                OidcData data = new OidcData(redirectUri);
+                                String state = data.getState();
+
+                                PENDING_OIDC.put(state, data);
 
                                 AuthenticationRequest oidcRequest = new AuthenticationRequest.Builder(
                                         new ResponseType("code"),
                                         new Scope("openid"),
-                                        provider.clientID,
-                                        callback)
-                                        .endpointURI(provider.authUri)
-                                        .state(state)
-                                        .nonce(nonce)
-                                        .build();
+                                        provider.clientID, callback).endpointURI(provider.authUri)
+                                        .state(new State(state)).nonce(data.nonce).build();
 
                                 if (redirectUri.equals(Constants.FRONTEND_URL + "/login")) {
                                     return HttpResponse.redirect302(oidcRequest.toURI().toString());
                                 }
                                 return HttpResponse.ok200().withHtml(
-                                        "<!DOCTYPE html><html style= \"color: white;background: #0f0f0f;\"><body>"
-                                                + "<h3>Warning:</h3> You are trying to give <pre style=\"font-size: 1.2rem;\">"
-                                                + redirectUri
-                                                + "</pre> access to your Piped account. If you wish to continue click <a style=\"text-decoration: underline;color: inherit;\"href=\""
-                                                + oidcRequest.toURI().toString()
-                                                + "\">here</a></body></html>");
+                                        "<!DOCTYPE html><html style=\"color-scheme: dark light;\"><body>" +
+                                                "<h3>Warning:</h3> You are trying to give <pre style=\"font-size: 1.2rem;\">" +
+                                                redirectUri +
+                                                "</pre> access to your Piped account. If you wish to continue click " +
+                                                "<a style=\"text-decoration: underline;color: inherit;\"href=\"" +
+                                                oidcRequest.toURI().toString() +
+                                                "\">here</a></body></html>");
                             }
                             case "callback" -> {
                                 ClientAuthentication clientAuth = new ClientSecretBasic(provider.clientID, provider.clientSecret);
 
-                                AuthenticationResponse response = AuthenticationResponseParser.parse(
-                                        URI.create(request.getFullUrl())
-                                );
+                                AuthenticationSuccessResponse sr = parseOidcUri(URI.create(request.getFullUrl()));
 
-                                if (response instanceof AuthenticationErrorResponse) {
-                                    // The OpenID provider returned an error
-                                    System.err.println(response.toErrorResponse().getErrorObject());
-                                    return HttpResponse.ofCode(500).withHtml("OpenID provider returned an error:\n\n" + response.toErrorResponse().getErrorObject().toString());
+                                OidcData data = PENDING_OIDC.get(sr.getState().toString());
+                                if (data == null) {
+                                    return HttpResponse.ofCode(400).withHtml(
+                                            "Your oidc provider sent invalid state data. Try again or contact your oidc admin"
+                                    );
                                 }
-                                AuthenticationSuccessResponse sr = response.toSuccessResponse();
-
                                 AuthorizationCode code = sr.getAuthorizationCode();
-                                AuthorizationGrant codeGrant = new AuthorizationCodeGrant(
-                                        code, callback
-                                );
+                                AuthorizationGrant codeGrant = new AuthorizationCodeGrant(code, callback);
+
 
                                 TokenRequest tr = new TokenRequest(provider.tokenUri, clientAuth, codeGrant);
-                                TokenResponse tokenResponse = OIDCTokenResponseParser.parse(tr.toHTTPRequest().send());
+                                OIDCTokenResponse tokenResponse = (OIDCTokenResponse) OIDCTokenResponseParser.parse(tr.toHTTPRequest().send());
 
                                 if (!tokenResponse.indicatesSuccess()) {
                                     TokenErrorResponse errorResponse = tokenResponse.toErrorResponse();
                                     return HttpResponse.ofCode(500).withHtml("Failure while trying to request token:\n\n" + errorResponse.getErrorObject().getDescription());
                                 }
 
-                                OIDCTokenResponse successResponse = (OIDCTokenResponse) tokenResponse.toSuccessResponse();
+                                OIDCTokenResponse successResponse = tokenResponse.toSuccessResponse();
 
+                                if (data.isInvalidNonce((String) successResponse.getOIDCTokens().getIDToken().getJWTClaimsSet().getClaim("nonce"))) {
+                                    return HttpResponse.ofCode(400).withHtml(
+                                            "Your oidc provider sent an invalid nonce. Try again or contact your oidc admin"
+                                    );
+                                }
 
                                 UserInfoRequest ur = new UserInfoRequest(provider.userinfoUri, successResponse.getOIDCTokens().getBearerAccessToken());
                                 UserInfoResponse userInfoResponse = UserInfoResponse.parse(ur.toHTTPRequest().send());
@@ -363,11 +367,57 @@ AsyncServlet mainServlet(Executor executor) {
                                 UserInfo userInfo = userInfoResponse.toSuccessResponse().getUserInfo();
 
                                 String sessionId = UserHandlers.oidcCallbackResponse(provider.name, userInfo.getSubject().toString());
+                                return HttpResponse.redirect302(data.data + "?session=" + sessionId);
+                            }
+                            case "delete" -> {
+                                ClientAuthentication clientAuth = new ClientSecretBasic(provider.clientID, provider.clientSecret);
+
+                                AuthenticationSuccessResponse sr = parseOidcUri(URI.create(request.getFullUrl()));
+
+                                OidcData data = UserHandlers.PENDING_OIDC.get(sr.getState().toString());
+                                if (data == null) {
+                                    return HttpResponse.ofCode(400).withHtml(
+                                            "Your oidc provider sent invalid state data. Try again or contact your oidc admin"
+                                    );
+                                }
+
+                                long start = Long.parseLong(data.data.split("\\|")[1]);
+                                String session = data.data.split("\\|")[0];
+
+                                AuthorizationCode code = sr.getAuthorizationCode();
+                                AuthorizationGrant codeGrant = new AuthorizationCodeGrant(code, new URI(Constants.PUBLIC_URL + request.getPath()));
+
+
+                                TokenRequest tr = new TokenRequest(provider.tokenUri, clientAuth, codeGrant);
+                                TokenResponse tokenResponse = OIDCTokenResponseParser.parse(tr.toHTTPRequest().send());
 
-                                return HttpResponse.redirect302(sr.getState().toString().split("\\.", 2)[1] + "?session=" + sessionId);
+                                if (!tokenResponse.indicatesSuccess()) {
+                                    TokenErrorResponse errorResponse = tokenResponse.toErrorResponse();
+                                    return HttpResponse.ofCode(500).withHtml("Failure while trying to request token:\n\n" + errorResponse.getErrorObject().getDescription());
+                                }
+
+                                OIDCTokenResponse successResponse = (OIDCTokenResponse) tokenResponse.toSuccessResponse();
+
+                                JWTClaimsSet claims = successResponse.getOIDCTokens().getIDToken().getJWTClaimsSet();
+
+                                if (data.isInvalidNonce((String) claims.getClaim("nonce"))) {
+                                    return HttpResponse.ofCode(400).withHtml(
+                                            "Your oidc provider sent an invalid nonce. Please try again or contact your oidc admin."
+                                    );
+                                }
+
+                                long authTime = (long) claims.getClaim("auth_time");
+
+                                if (authTime < start) {
+                                    return HttpResponse.ofCode(500).withHtml(
+                                            "Your oidc provider didn't verify your identity. Please try again or contact your oidc admin."
+                                    );
+                                }
+
+                                return HttpResponse.redirect302(Constants.FRONTEND_URL + "/preferences?deleted=" + UserHandlers.deleteOidcUserResponse(session));
                             }
                             default -> {
-                                return HttpResponse.ofCode(500).withHtml("Invalid function `" + function + "`.");
+                                return HttpResponse.ofCode(500).withHtml("Invalid function `" + function + "`");
                             }
                         }
 
@@ -630,6 +680,17 @@ private static OidcProvider getOidcProvider(String provider) {
         return null;
     }
 
+    private static AuthenticationSuccessResponse parseOidcUri(URI uri) throws Exception {
+        AuthenticationResponse response = AuthenticationResponseParser.parse(uri);
+
+        if (response instanceof AuthenticationErrorResponse) {
+            // The OpenID provider returned an error
+            System.err.println(response.toErrorResponse().getErrorObject());
+            throw new Exception(response.toErrorResponse().getErrorObject().toString());
+        }
+        return response.toSuccessResponse();
+    }
+
     private static String[] getArray(String s) {
 
         if (s == null) {
diff --git a/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java b/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java
index 7059bc29..207081f4 100644
--- a/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java
+++ b/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java
@@ -1,6 +1,10 @@
 package me.kavin.piped.server.handlers.auth;
 
 import com.fasterxml.jackson.core.JsonProcessingException;
+import com.nimbusds.oauth2.sdk.ResponseType;
+import com.nimbusds.oauth2.sdk.Scope;
+import com.nimbusds.oauth2.sdk.id.State;
+import com.nimbusds.openid.connect.sdk.AuthenticationRequest;
 import jakarta.persistence.criteria.CriteriaBuilder;
 import jakarta.persistence.criteria.CriteriaQuery;
 import jakarta.persistence.criteria.Root;
@@ -9,6 +13,8 @@
 import me.kavin.piped.utils.DatabaseSessionFactory;
 import me.kavin.piped.utils.ExceptionHandler;
 import me.kavin.piped.utils.RequestUtils;
+import me.kavin.piped.utils.obj.OidcData;
+import me.kavin.piped.utils.obj.OidcProvider;
 import me.kavin.piped.utils.obj.db.User;
 import me.kavin.piped.utils.resp.*;
 import org.apache.commons.codec.digest.DigestUtils;
@@ -19,6 +25,10 @@
 import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
 
 import java.io.IOException;
+import java.net.URI;
+import java.time.Instant;
+import java.util.HashMap;
+import java.util.Map;
 import java.util.Set;
 import java.util.UUID;
 
@@ -27,6 +37,7 @@
 public class UserHandlers {
     private static final Argon2PasswordEncoder argon2PasswordEncoder = Argon2PasswordEncoder.defaultsForSpringSecurity_v5_8();
     private static final BCryptPasswordEncoder bcryptPasswordEncoder = new BCryptPasswordEncoder();
+    public static final Map<String, OidcData> PENDING_OIDC = new HashMap<>();
 
     public static byte[] registerResponse(String user, String pass) throws Exception {
 
@@ -111,6 +122,7 @@ public static byte[] loginResponse(String user, String pass)
 
     public static String oidcCallbackResponse(String provider, String uid) {
         try (Session s = DatabaseSessionFactory.createSession()) {
+            // TODO: Add oidc provider to database
             String dbName = provider + "-" + uid;
             CriteriaBuilder cb = s.getCriteriaBuilder();
             CriteriaQuery<User> cr = cb.createQuery(User.class);
@@ -148,12 +160,21 @@ public static byte[] deleteUserResponse(String session, String pass) throws IOEx
 
             String hash = user.getPassword();
 
-            if (hash.equals("")) {
-                //TODO: Authorize against oidc provider before deletion
-                var tr = s.beginTransaction();
-                s.remove(user);
-                tr.commit();
-                return mapper.writeValueAsBytes(new DeleteUserResponse(user.getUsername()));
+            if (hash.isEmpty()) {
+                //TODO: Get user from oidc table and lookup provider
+                OidcProvider provider = Constants.OIDC_PROVIDERS.get(0);
+                URI callback = URI.create(String.format("%s/oidc/%s/delete", Constants.PUBLIC_URL, provider.name));
+                OidcData data = new OidcData(session + "|" + Instant.now().getEpochSecond());
+                String state = data.getState();
+                PENDING_OIDC.put(state, data);
+
+                AuthenticationRequest oidcRequest = new AuthenticationRequest.Builder(
+                        new ResponseType("code"),
+                        new Scope("openid"), provider.clientID, callback).endpointURI(provider.authUri)
+                            .state(new State(state)).nonce(data.nonce).maxAge(0).build();
+
+
+                return String.format("{\"redirect\": \"%s\"}", oidcRequest.toURI().toString()).getBytes();
             }
             if (!hashMatch(hash, pass))
                 ExceptionHandler.throwErrorResponse(new IncorrectCredentialsResponse());
@@ -166,6 +187,18 @@ public static byte[] deleteUserResponse(String session, String pass) throws IOEx
         }
     }
 
+    public static String deleteOidcUserResponse(String session) throws IOException {
+        try (Session s = DatabaseSessionFactory.createSession()) {
+            User user = DatabaseHelper.getUserFromSession(session);
+
+            var tr = s.beginTransaction();
+            s.remove(user);
+            tr.commit();
+
+            return user.getUsername();
+        }
+    }
+
     public static byte[] logoutResponse(String session) throws JsonProcessingException {
 
         if (StringUtils.isBlank(session))
diff --git a/src/main/java/me/kavin/piped/utils/obj/OidcData.java b/src/main/java/me/kavin/piped/utils/obj/OidcData.java
new file mode 100644
index 00000000..f1bfd6c0
--- /dev/null
+++ b/src/main/java/me/kavin/piped/utils/obj/OidcData.java
@@ -0,0 +1,36 @@
+package me.kavin.piped.utils.obj;
+
+import com.nimbusds.openid.connect.sdk.Nonce;
+
+import java.nio.charset.StandardCharsets;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.util.Base64;
+
+public class OidcData {
+    public final Nonce nonce;
+
+    public String data;
+
+    public OidcData(String data) {
+        this.nonce = new Nonce();
+        this.data = data;
+    }
+
+    public boolean isInvalidNonce(String nonce) {
+        return !nonce.equals(this.nonce.toString());
+    }
+
+    public String getState() {
+        String value = nonce + data;
+
+        try {
+            MessageDigest md = MessageDigest.getInstance("SHA-256");
+            byte[] hash = md.digest(value.getBytes(StandardCharsets.UTF_8));
+            return Base64.getEncoder().encodeToString(hash);
+
+        } catch (NoSuchAlgorithmException e) {
+            throw new RuntimeException("SHA-256 not supported", e);
+        }
+    }
+}

From c1fde372a5d664005490f09578a96cf1ad72d9e4 Mon Sep 17 00:00:00 2001
From: Jeidnx <jeidnx@domainhier.de>
Date: Thu, 26 Oct 2023 13:24:27 +0200
Subject: [PATCH 10/13] Refactor oidc logic into UserHandlers

---
 .../me/kavin/piped/server/ServerLauncher.java | 159 +---------------
 .../server/handlers/auth/UserHandlers.java    | 171 ++++++++++++++++--
 2 files changed, 159 insertions(+), 171 deletions(-)

diff --git a/src/main/java/me/kavin/piped/server/ServerLauncher.java b/src/main/java/me/kavin/piped/server/ServerLauncher.java
index 3394909b..3098bfdd 100644
--- a/src/main/java/me/kavin/piped/server/ServerLauncher.java
+++ b/src/main/java/me/kavin/piped/server/ServerLauncher.java
@@ -2,13 +2,6 @@
 
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.JsonNode;
-import com.nimbusds.jwt.JWTClaimsSet;
-import com.nimbusds.oauth2.sdk.*;
-import com.nimbusds.oauth2.sdk.auth.ClientAuthentication;
-import com.nimbusds.oauth2.sdk.auth.ClientSecretBasic;
-import com.nimbusds.oauth2.sdk.id.State;
-import com.nimbusds.openid.connect.sdk.*;
-import com.nimbusds.openid.connect.sdk.claims.UserInfo;
 import com.rometools.rome.feed.synd.SyndFeed;
 import com.rometools.rome.io.SyndFeedInput;
 import io.activej.config.Config;
@@ -44,11 +37,8 @@
 import java.io.ByteArrayInputStream;
 import java.net.InetSocketAddress;
 import java.net.URI;
-import java.util.HashMap;
-import java.util.Map;
 import java.util.Objects;
 import java.util.concurrent.Executor;
-import java.util.concurrent.TimeUnit;
 
 import static io.activej.config.converter.ConfigConverters.ofInetSocketAddress;
 import static io.activej.http.HttpHeaders.*;
@@ -61,7 +51,6 @@ public class ServerLauncher extends MultithreadedHttpServerLauncher {
 
     private static final HttpHeader FILE_NAME = HttpHeaders.of("x-file-name");
     private static final HttpHeader LAST_ETAG = HttpHeaders.of("x-last-etag");
-    private static final Map<String, OidcData> PENDING_OIDC = new HashMap<>();
 
     @Provides
     Executor executor() {
@@ -291,137 +280,12 @@ AsyncServlet mainServlet(Executor executor) {
                         if (provider == null)
                             return HttpResponse.ofCode(500).withHtml("Can't find the provider on the server");
 
-                        URI callback = new URI(Constants.PUBLIC_URL + "/oidc/" + provider.name + "/callback");
-
-                        switch (function) {
-                            case "login" -> {
-                                String redirectUri = request.getQueryParameter("redirect");
-
-                                if (StringUtils.isBlank(redirectUri)) {
-                                    return HttpResponse.ofCode(400).withHtml("redirect is a required parameter");
-                                }
-
-                                OidcData data = new OidcData(redirectUri);
-                                String state = data.getState();
-
-                                PENDING_OIDC.put(state, data);
-
-                                AuthenticationRequest oidcRequest = new AuthenticationRequest.Builder(
-                                        new ResponseType("code"),
-                                        new Scope("openid"),
-                                        provider.clientID, callback).endpointURI(provider.authUri)
-                                        .state(new State(state)).nonce(data.nonce).build();
-
-                                if (redirectUri.equals(Constants.FRONTEND_URL + "/login")) {
-                                    return HttpResponse.redirect302(oidcRequest.toURI().toString());
-                                }
-                                return HttpResponse.ok200().withHtml(
-                                        "<!DOCTYPE html><html style=\"color-scheme: dark light;\"><body>" +
-                                                "<h3>Warning:</h3> You are trying to give <pre style=\"font-size: 1.2rem;\">" +
-                                                redirectUri +
-                                                "</pre> access to your Piped account. If you wish to continue click " +
-                                                "<a style=\"text-decoration: underline;color: inherit;\"href=\"" +
-                                                oidcRequest.toURI().toString() +
-                                                "\">here</a></body></html>");
-                            }
-                            case "callback" -> {
-                                ClientAuthentication clientAuth = new ClientSecretBasic(provider.clientID, provider.clientSecret);
-
-                                AuthenticationSuccessResponse sr = parseOidcUri(URI.create(request.getFullUrl()));
-
-                                OidcData data = PENDING_OIDC.get(sr.getState().toString());
-                                if (data == null) {
-                                    return HttpResponse.ofCode(400).withHtml(
-                                            "Your oidc provider sent invalid state data. Try again or contact your oidc admin"
-                                    );
-                                }
-                                AuthorizationCode code = sr.getAuthorizationCode();
-                                AuthorizationGrant codeGrant = new AuthorizationCodeGrant(code, callback);
-
-
-                                TokenRequest tr = new TokenRequest(provider.tokenUri, clientAuth, codeGrant);
-                                OIDCTokenResponse tokenResponse = (OIDCTokenResponse) OIDCTokenResponseParser.parse(tr.toHTTPRequest().send());
-
-                                if (!tokenResponse.indicatesSuccess()) {
-                                    TokenErrorResponse errorResponse = tokenResponse.toErrorResponse();
-                                    return HttpResponse.ofCode(500).withHtml("Failure while trying to request token:\n\n" + errorResponse.getErrorObject().getDescription());
-                                }
-
-                                OIDCTokenResponse successResponse = tokenResponse.toSuccessResponse();
-
-                                if (data.isInvalidNonce((String) successResponse.getOIDCTokens().getIDToken().getJWTClaimsSet().getClaim("nonce"))) {
-                                    return HttpResponse.ofCode(400).withHtml(
-                                            "Your oidc provider sent an invalid nonce. Try again or contact your oidc admin"
-                                    );
-                                }
-
-                                UserInfoRequest ur = new UserInfoRequest(provider.userinfoUri, successResponse.getOIDCTokens().getBearerAccessToken());
-                                UserInfoResponse userInfoResponse = UserInfoResponse.parse(ur.toHTTPRequest().send());
-
-                                if (!userInfoResponse.indicatesSuccess()) {
-                                    System.out.println(userInfoResponse.toErrorResponse().getErrorObject().getCode());
-                                    System.out.println(userInfoResponse.toErrorResponse().getErrorObject().getDescription());
-                                    return HttpResponse.ofCode(500).withHtml("Failed to query userInfo:\n\n" + userInfoResponse.toErrorResponse().getErrorObject().getDescription());
-                                }
-
-                                UserInfo userInfo = userInfoResponse.toSuccessResponse().getUserInfo();
-
-                                String sessionId = UserHandlers.oidcCallbackResponse(provider.name, userInfo.getSubject().toString());
-                                return HttpResponse.redirect302(data.data + "?session=" + sessionId);
-                            }
-                            case "delete" -> {
-                                ClientAuthentication clientAuth = new ClientSecretBasic(provider.clientID, provider.clientSecret);
-
-                                AuthenticationSuccessResponse sr = parseOidcUri(URI.create(request.getFullUrl()));
-
-                                OidcData data = UserHandlers.PENDING_OIDC.get(sr.getState().toString());
-                                if (data == null) {
-                                    return HttpResponse.ofCode(400).withHtml(
-                                            "Your oidc provider sent invalid state data. Try again or contact your oidc admin"
-                                    );
-                                }
-
-                                long start = Long.parseLong(data.data.split("\\|")[1]);
-                                String session = data.data.split("\\|")[0];
-
-                                AuthorizationCode code = sr.getAuthorizationCode();
-                                AuthorizationGrant codeGrant = new AuthorizationCodeGrant(code, new URI(Constants.PUBLIC_URL + request.getPath()));
-
-
-                                TokenRequest tr = new TokenRequest(provider.tokenUri, clientAuth, codeGrant);
-                                TokenResponse tokenResponse = OIDCTokenResponseParser.parse(tr.toHTTPRequest().send());
-
-                                if (!tokenResponse.indicatesSuccess()) {
-                                    TokenErrorResponse errorResponse = tokenResponse.toErrorResponse();
-                                    return HttpResponse.ofCode(500).withHtml("Failure while trying to request token:\n\n" + errorResponse.getErrorObject().getDescription());
-                                }
-
-                                OIDCTokenResponse successResponse = (OIDCTokenResponse) tokenResponse.toSuccessResponse();
-
-                                JWTClaimsSet claims = successResponse.getOIDCTokens().getIDToken().getJWTClaimsSet();
-
-                                if (data.isInvalidNonce((String) claims.getClaim("nonce"))) {
-                                    return HttpResponse.ofCode(400).withHtml(
-                                            "Your oidc provider sent an invalid nonce. Please try again or contact your oidc admin."
-                                    );
-                                }
-
-                                long authTime = (long) claims.getClaim("auth_time");
-
-                                if (authTime < start) {
-                                    return HttpResponse.ofCode(500).withHtml(
-                                            "Your oidc provider didn't verify your identity. Please try again or contact your oidc admin."
-                                    );
-                                }
-
-                                return HttpResponse.redirect302(Constants.FRONTEND_URL + "/preferences?deleted=" + UserHandlers.deleteOidcUserResponse(session));
-                            }
-                            default -> {
-                                return HttpResponse.ofCode(500).withHtml("Invalid function `" + function + "`");
-                            }
-                        }
-
-
+                        return switch (function) {
+                            case "login" -> UserHandlers.oidcLoginResponse(provider, request.getQueryParameter("redirect"));
+                            case "callback" -> UserHandlers.oidcCallbackResponse(provider, URI.create(request.getFullUrl()));
+                            case "delete" -> UserHandlers.oidcDeleteResponse(provider, URI.create(request.getFullUrl()));
+                            default -> HttpResponse.ofCode(500).withHtml("Invalid function `" + function + "`");
+                        };
                     } catch (Exception e) {
                         return getErrorResponse(e, request.getPath());
                     }
@@ -680,17 +544,6 @@ private static OidcProvider getOidcProvider(String provider) {
         return null;
     }
 
-    private static AuthenticationSuccessResponse parseOidcUri(URI uri) throws Exception {
-        AuthenticationResponse response = AuthenticationResponseParser.parse(uri);
-
-        if (response instanceof AuthenticationErrorResponse) {
-            // The OpenID provider returned an error
-            System.err.println(response.toErrorResponse().getErrorObject());
-            throw new Exception(response.toErrorResponse().getErrorObject().toString());
-        }
-        return response.toSuccessResponse();
-    }
-
     private static String[] getArray(String s) {
 
         if (s == null) {
diff --git a/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java b/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java
index 207081f4..40df4df6 100644
--- a/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java
+++ b/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java
@@ -1,10 +1,14 @@
 package me.kavin.piped.server.handlers.auth;
 
 import com.fasterxml.jackson.core.JsonProcessingException;
-import com.nimbusds.oauth2.sdk.ResponseType;
-import com.nimbusds.oauth2.sdk.Scope;
+import com.nimbusds.jwt.JWTClaimsSet;
+import com.nimbusds.oauth2.sdk.*;
+import com.nimbusds.oauth2.sdk.auth.ClientAuthentication;
+import com.nimbusds.oauth2.sdk.auth.ClientSecretBasic;
 import com.nimbusds.oauth2.sdk.id.State;
-import com.nimbusds.openid.connect.sdk.AuthenticationRequest;
+import com.nimbusds.openid.connect.sdk.*;
+import com.nimbusds.openid.connect.sdk.claims.UserInfo;
+import io.activej.http.HttpResponse;
 import jakarta.persistence.criteria.CriteriaBuilder;
 import jakarta.persistence.criteria.CriteriaQuery;
 import jakarta.persistence.criteria.Root;
@@ -120,7 +124,84 @@ public static byte[] loginResponse(String user, String pass)
         }
     }
 
-    public static String oidcCallbackResponse(String provider, String uid) {
+    public static HttpResponse oidcLoginResponse(OidcProvider provider, String redirectUri) throws Exception{
+        if (StringUtils.isBlank(redirectUri)) {
+            return HttpResponse.ofCode(400).withHtml("redirect is a required parameter");
+        }
+
+        URI callback = new URI(Constants.PUBLIC_URL + "/oidc/" + provider.name + "/callback");
+        OidcData data = new OidcData(redirectUri);
+        String state = data.getState();
+
+        PENDING_OIDC.put(state, data);
+
+        AuthenticationRequest oidcRequest = new AuthenticationRequest.Builder(
+                new ResponseType("code"),
+                new Scope("openid"),
+                provider.clientID, callback).endpointURI(provider.authUri)
+                .state(new State(state)).nonce(data.nonce).build();
+
+        if (redirectUri.equals(Constants.FRONTEND_URL + "/login")) {
+            return HttpResponse.redirect302(oidcRequest.toURI().toString());
+        }
+        return HttpResponse.ok200().withHtml(
+                "<!DOCTYPE html><html style=\"color-scheme: dark light;\"><body>" +
+                        "<h3>Warning:</h3> You are trying to give <pre style=\"font-size: 1.2rem;\">" +
+                        redirectUri +
+                        "</pre> access to your Piped account. If you wish to continue click " +
+                        "<a style=\"text-decoration: underline;color: inherit;\"href=\"" +
+                        oidcRequest.toURI().toString() +
+                        "\">here</a></body></html>");
+    }
+    public static HttpResponse oidcCallbackResponse(OidcProvider provider, URI requestUri) throws Exception {
+        ClientAuthentication clientAuth = new ClientSecretBasic(provider.clientID, provider.clientSecret);
+
+        AuthenticationSuccessResponse sr = parseOidcUri(requestUri);
+
+        OidcData data = PENDING_OIDC.get(sr.getState().toString());
+        if (data == null) {
+            return HttpResponse.ofCode(400).withHtml(
+                    "Your oidc provider sent invalid state data. Try again or contact your oidc admin"
+            );
+        }
+
+        URI callback = new URI(Constants.PUBLIC_URL + "/oidc/" + provider.name + "/callback");
+        AuthorizationCode code = sr.getAuthorizationCode();
+        AuthorizationGrant codeGrant = new AuthorizationCodeGrant(code, callback);
+
+
+        TokenRequest tokenReq = new TokenRequest(provider.tokenUri, clientAuth, codeGrant);
+        OIDCTokenResponse tokenResponse = (OIDCTokenResponse) OIDCTokenResponseParser.parse(tokenReq.toHTTPRequest().send());
+
+        if (!tokenResponse.indicatesSuccess()) {
+            TokenErrorResponse errorResponse = tokenResponse.toErrorResponse();
+            return HttpResponse.ofCode(500).withHtml("Failure while trying to request token:\n\n" + errorResponse.getErrorObject().getDescription());
+        }
+
+        OIDCTokenResponse successResponse = tokenResponse.toSuccessResponse();
+
+        if (data.isInvalidNonce((String) successResponse.getOIDCTokens().getIDToken().getJWTClaimsSet().getClaim("nonce"))) {
+            return HttpResponse.ofCode(400).withHtml(
+                    "Your oidc provider sent an invalid nonce. Try again or contact your oidc admin"
+            );
+        }
+
+        UserInfoRequest ur = new UserInfoRequest(provider.userinfoUri, successResponse.getOIDCTokens().getBearerAccessToken());
+        UserInfoResponse userInfoResponse = UserInfoResponse.parse(ur.toHTTPRequest().send());
+
+        if (!userInfoResponse.indicatesSuccess()) {
+            System.out.println(userInfoResponse.toErrorResponse().getErrorObject().getCode());
+            System.out.println(userInfoResponse.toErrorResponse().getErrorObject().getDescription());
+            return HttpResponse.ofCode(500).withHtml(
+                    "The userinfo endpoint returned an error. Please try again or contact your oidc admin\n\n" +
+                            userInfoResponse.toErrorResponse().getErrorObject().getDescription());
+        }
+
+        UserInfo userInfo = userInfoResponse.toSuccessResponse().getUserInfo();
+
+
+        String uid = userInfo.getSubject().toString();
+        String sessionId;
         try (Session s = DatabaseSessionFactory.createSession()) {
             // TODO: Add oidc provider to database
             String dbName = provider + "-" + uid;
@@ -141,11 +222,66 @@ public static String oidcCallbackResponse(String provider, String uid) {
                 tr.commit();
 
 
-                return newuser.getSessionId();
-            }
-            return dbuser.getSessionId();
+                sessionId = newuser.getSessionId();
+            } else sessionId = dbuser.getSessionId();
+        }
+        return HttpResponse.redirect302(data.data + "?session=" + sessionId);
+
+    }
+
+    public static HttpResponse oidcDeleteResponse(OidcProvider provider, URI requestUri) throws Exception {
+        ClientAuthentication clientAuth = new ClientSecretBasic(provider.clientID, provider.clientSecret);
+
+        AuthenticationSuccessResponse sr = parseOidcUri(requestUri);
+
+        OidcData data = UserHandlers.PENDING_OIDC.get(sr.getState().toString());
+        if (data == null) {
+            return HttpResponse.ofCode(400).withHtml(
+                    "Your oidc provider sent invalid state data. Try again or contact your oidc admin"
+            );
         }
 
+        long start = Long.parseLong(data.data.split("\\|")[1]);
+        String session = data.data.split("\\|")[0];
+
+        URI callback = new URI(Constants.PUBLIC_URL + "/oidc/" + provider.name + "/delete");
+        AuthorizationCode code = sr.getAuthorizationCode();
+        AuthorizationGrant codeGrant = new AuthorizationCodeGrant(code, callback);
+
+
+        TokenRequest tokenRequest = new TokenRequest(provider.tokenUri, clientAuth, codeGrant);
+        TokenResponse tokenResponse = OIDCTokenResponseParser.parse(tokenRequest.toHTTPRequest().send());
+
+        if (!tokenResponse.indicatesSuccess()) {
+            TokenErrorResponse errorResponse = tokenResponse.toErrorResponse();
+            return HttpResponse.ofCode(500).withHtml("Failure while trying to request token:\n\n" + errorResponse.getErrorObject().getDescription());
+        }
+
+        OIDCTokenResponse successResponse = (OIDCTokenResponse) tokenResponse.toSuccessResponse();
+
+        JWTClaimsSet claims = successResponse.getOIDCTokens().getIDToken().getJWTClaimsSet();
+
+        if (data.isInvalidNonce((String) claims.getClaim("nonce"))) {
+            return HttpResponse.ofCode(400).withHtml(
+                    "Your oidc provider sent an invalid nonce. Please try again or contact your oidc admin."
+            );
+        }
+
+        long authTime = (long) claims.getClaim("auth_time");
+
+        if (authTime < start) {
+            return HttpResponse.ofCode(500).withHtml(
+                    "Your oidc provider didn't verify your identity. Please try again or contact your oidc admin."
+            );
+        }
+
+        try (Session s = DatabaseSessionFactory.createSession()) {
+
+            var tr = s.beginTransaction();
+            s.remove(DatabaseHelper.getUserFromSession(session));
+            tr.commit();
+        }
+        return HttpResponse.redirect302(Constants.FRONTEND_URL + "/preferences?deleted=" + session);
     }
 
     public static byte[] deleteUserResponse(String session, String pass) throws IOException {
@@ -187,17 +323,6 @@ public static byte[] deleteUserResponse(String session, String pass) throws IOEx
         }
     }
 
-    public static String deleteOidcUserResponse(String session) throws IOException {
-        try (Session s = DatabaseSessionFactory.createSession()) {
-            User user = DatabaseHelper.getUserFromSession(session);
-
-            var tr = s.beginTransaction();
-            s.remove(user);
-            tr.commit();
-
-            return user.getUsername();
-        }
-    }
 
     public static byte[] logoutResponse(String session) throws JsonProcessingException {
 
@@ -217,4 +342,14 @@ public static byte[] logoutResponse(String session) throws JsonProcessingExcepti
 
         return Constants.mapper.writeValueAsBytes(new AuthenticationFailureResponse());
     }
+
+    private static AuthenticationSuccessResponse parseOidcUri(URI uri) throws Exception {
+        AuthenticationResponse response = AuthenticationResponseParser.parse(uri);
+
+        if (response instanceof AuthenticationErrorResponse) {
+            System.err.println(response.toErrorResponse().getErrorObject());
+            throw new Exception(response.toErrorResponse().getErrorObject().toString());
+        }
+        return response.toSuccessResponse();
+    }
 }

From 024435ff54024d793cd2861196950a475c9eb41c Mon Sep 17 00:00:00 2001
From: Kavin <20838718+FireMasterK@users.noreply.github.com>
Date: Thu, 26 Oct 2023 17:39:25 +0100
Subject: [PATCH 11/13] Add database migration for username length change.

---
 .../resources/changelog/db.changelog-master.xml   |  1 +
 src/main/resources/changelog/version/2-oidc.xml   | 15 +++++++++++++++
 2 files changed, 16 insertions(+)
 create mode 100644 src/main/resources/changelog/version/2-oidc.xml

diff --git a/src/main/resources/changelog/db.changelog-master.xml b/src/main/resources/changelog/db.changelog-master.xml
index 68fb5f2b..b8b5e3fe 100644
--- a/src/main/resources/changelog/db.changelog-master.xml
+++ b/src/main/resources/changelog/db.changelog-master.xml
@@ -6,5 +6,6 @@
 
     <include file="version/0-init.xml" relativeToChangelogFile="true"/>
     <include file="version/1-fix-subs.xml" relativeToChangelogFile="true"/>
+    <include file="version/2-oidc.xml" relativeToChangelogFile="true"/>
 
 </databaseChangeLog>
diff --git a/src/main/resources/changelog/version/2-oidc.xml b/src/main/resources/changelog/version/2-oidc.xml
new file mode 100644
index 00000000..817e29c1
--- /dev/null
+++ b/src/main/resources/changelog/version/2-oidc.xml
@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<databaseChangeLog xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
+                   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+                   xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog
+                   https://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-latest.xsd">
+
+    <changeSet id="2-0" author="kavin" runInTransaction="false">
+        <!-- alter username's varchar length to 32 from 24 -->
+        <sql>ALTER TABLE users ALTER COLUMN username TYPE varchar(32);</sql>
+        <rollback>
+            <sql>ALTER TABLE users ALTER COLUMN username TYPE varchar(24);</sql>
+        </rollback>
+    </changeSet>
+
+</databaseChangeLog>

From 470efd80683529deefc5d120aa3a65b5a40dfa54 Mon Sep 17 00:00:00 2001
From: Jeidnx <jeidnx@domainhier.de>
Date: Sun, 29 Oct 2023 20:01:24 +0100
Subject: [PATCH 12/13] Revert "Add database migration for username length
 change."

This reverts commit 024435ff54024d793cd2861196950a475c9eb41c.
---
 .../resources/changelog/db.changelog-master.xml   |  1 -
 src/main/resources/changelog/version/2-oidc.xml   | 15 ---------------
 2 files changed, 16 deletions(-)
 delete mode 100644 src/main/resources/changelog/version/2-oidc.xml

diff --git a/src/main/resources/changelog/db.changelog-master.xml b/src/main/resources/changelog/db.changelog-master.xml
index b8b5e3fe..68fb5f2b 100644
--- a/src/main/resources/changelog/db.changelog-master.xml
+++ b/src/main/resources/changelog/db.changelog-master.xml
@@ -6,6 +6,5 @@
 
     <include file="version/0-init.xml" relativeToChangelogFile="true"/>
     <include file="version/1-fix-subs.xml" relativeToChangelogFile="true"/>
-    <include file="version/2-oidc.xml" relativeToChangelogFile="true"/>
 
 </databaseChangeLog>
diff --git a/src/main/resources/changelog/version/2-oidc.xml b/src/main/resources/changelog/version/2-oidc.xml
deleted file mode 100644
index 817e29c1..00000000
--- a/src/main/resources/changelog/version/2-oidc.xml
+++ /dev/null
@@ -1,15 +0,0 @@
-<?xml version="1.0" encoding="UTF-8" standalone="no"?>
-<databaseChangeLog xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
-                   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-                   xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog
-                   https://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-latest.xsd">
-
-    <changeSet id="2-0" author="kavin" runInTransaction="false">
-        <!-- alter username's varchar length to 32 from 24 -->
-        <sql>ALTER TABLE users ALTER COLUMN username TYPE varchar(32);</sql>
-        <rollback>
-            <sql>ALTER TABLE users ALTER COLUMN username TYPE varchar(24);</sql>
-        </rollback>
-    </changeSet>
-
-</databaseChangeLog>

From 5f6a83aa735040b942fbd4e352731048237a7868 Mon Sep 17 00:00:00 2001
From: Kavin <20838718+FireMasterK@users.noreply.github.com>
Date: Sun, 29 Oct 2023 21:26:42 +0000
Subject: [PATCH 13/13] Add code from the meeting.

---
 .../server/handlers/auth/UserHandlers.java    | 12 +++++++++++-
 .../piped/utils/obj/db/OidcUserData.java      | 19 +++++++++++++++++++
 2 files changed, 30 insertions(+), 1 deletion(-)
 create mode 100644 src/main/java/me/kavin/piped/utils/obj/db/OidcUserData.java

diff --git a/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java b/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java
index 40df4df6..7fb56ca1 100644
--- a/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java
+++ b/src/main/java/me/kavin/piped/server/handlers/auth/UserHandlers.java
@@ -19,6 +19,7 @@
 import me.kavin.piped.utils.RequestUtils;
 import me.kavin.piped.utils.obj.OidcData;
 import me.kavin.piped.utils.obj.OidcProvider;
+import me.kavin.piped.utils.obj.db.OidcUserData;
 import me.kavin.piped.utils.obj.db.User;
 import me.kavin.piped.utils.resp.*;
 import org.apache.commons.codec.digest.DigestUtils;
@@ -297,6 +298,14 @@ public static byte[] deleteUserResponse(String session, String pass) throws IOEx
             String hash = user.getPassword();
 
             if (hash.isEmpty()) {
+
+                CriteriaBuilder cb = s.getCriteriaBuilder();
+                CriteriaQuery<OidcUserData> cr = cb.createQuery(OidcUserData.class);
+                Root<OidcUserData> root = cr.from(OidcUserData.class);
+                cr.select(root).where(cb.equal(root.get("user"), user.getId()));
+
+                OidcUserData oidcUserData = s.createQuery(cr).uniqueResult();
+
                 //TODO: Get user from oidc table and lookup provider
                 OidcProvider provider = Constants.OIDC_PROVIDERS.get(0);
                 URI callback = URI.create(String.format("%s/oidc/%s/delete", Constants.PUBLIC_URL, provider.name));
@@ -310,7 +319,8 @@ public static byte[] deleteUserResponse(String session, String pass) throws IOEx
                             .state(new State(state)).nonce(data.nonce).maxAge(0).build();
 
 
-                return String.format("{\"redirect\": \"%s\"}", oidcRequest.toURI().toString()).getBytes();
+                return mapper.writeValueAsBytes(mapper.createObjectNode()
+                        .put("redirect", oidcRequest.toURI().toString()));
             }
             if (!hashMatch(hash, pass))
                 ExceptionHandler.throwErrorResponse(new IncorrectCredentialsResponse());
diff --git a/src/main/java/me/kavin/piped/utils/obj/db/OidcUserData.java b/src/main/java/me/kavin/piped/utils/obj/db/OidcUserData.java
new file mode 100644
index 00000000..e23d6216
--- /dev/null
+++ b/src/main/java/me/kavin/piped/utils/obj/db/OidcUserData.java
@@ -0,0 +1,19 @@
+package me.kavin.piped.utils.obj.db;
+
+import jakarta.persistence.*;
+
+@Entity
+@Table(name = "oidc_user_data")
+public class OidcUserData {
+
+    @Column(unique = true)
+    @Id
+    private String sub;
+
+    @OneToOne
+    private User user;
+
+    private String provider;
+
+
+}