ActivityPub: signed GET requests, fix Signature verification

16 files changed, 407 insertions, 312 deletions

diff --git a/src/main/java/com/juick/ActivityPubManager.java b/src/main/java/com/juick/ActivityPubManager.java
index a487afb1..db8a1acb 100644
--- a/src/main/java/com/juick/ActivityPubManager.java
+++ b/src/main/java/com/juick/ActivityPubManager.java
@@ -19,12 +19,13 @@ package com.juick;
 
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
-import com.fasterxml.jackson.databind.json.JsonMapper;
 import com.juick.model.Message;
 import com.juick.model.Reaction;
 import com.juick.model.User;
+import com.juick.service.ActivityPubService;
 import com.juick.service.MessagesService;
 import com.juick.service.SocialService;
+import com.juick.service.WebfingerService;
 import com.juick.service.activities.*;
 import com.juick.service.component.NotificationListener;
 import com.juick.service.component.PingEvent;
@@ -45,6 +46,7 @@ import org.apache.commons.lang3.StringUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.core.convert.ConversionService;
+import org.springframework.http.MediaType;
 import org.springframework.web.util.UriComponents;
 import org.springframework.web.util.UriComponentsBuilder;
 
@@ -62,7 +64,9 @@ import java.util.stream.Collectors;
 public class ActivityPubManager implements ActivityListener, NotificationListener {
     private static final Logger logger = LoggerFactory.getLogger("ActivityPub");
     @Inject
-    private SignatureManager signatureManager;
+    private ActivityPubService activityPubService;
+    @Inject
+    private WebfingerService webfingerService;
     @Inject
     private SocialService socialService;
     @Inject
@@ -84,12 +88,12 @@ public class ActivityPubManager implements ActivityListener, NotificationListene
         if (!followedUser.isAnonymous()) {
             // automatically accept follower requests
             Actor me = conversionService.convert(followedUser, Actor.class);
-            Actor follower = (Actor) signatureManager.getContext(URI.create(followEvent.getRequest().getActor())).get();
+            Actor follower = (Actor) activityPubService.get(URI.create(followEvent.getRequest().getActor())).get();
             Accept accept = new Accept();
             accept.setActor(me.getId());
             accept.setObject(followEvent.getRequest());
             try {
-                signatureManager.post(me, follower, accept);
+                activityPubService.post(me, follower, accept);
                 socialService.addFollower(followedUser, follower.getId());
                 logger.info("Follower added for {}", followedUser.getName());
             } catch (IOException | NoSuchAlgorithmException e) {
@@ -124,14 +128,14 @@ public class ActivityPubManager implements ActivityListener, NotificationListene
         Actor me = conversionService.convert(user, Actor.class);
         socialService.getFollowers(user).forEach(acct -> {
             try {
-                Actor follower = (Actor) signatureManager.getContext(URI.create(acct)).orElseThrow();
+                Actor follower = (Actor) activityPubService.get(URI.create(acct)).orElseThrow();
                 Delete delete = new Delete();
                 delete.setId(note.getId());
                 delete.setActor(me.getId());
                 delete.setPublished(note.getPublished());
                 delete.setObject(note);
                 logger.info("Deletion to follower {}", follower.getId());
-                signatureManager.post(me, follower, delete);
+                activityPubService.post(me, follower, delete);
             } catch (IOException | NoSuchAlgorithmException e) {
                 logger.warn("activitypub exception", e);
             } catch (NoSuchElementException ex) {
@@ -196,12 +200,12 @@ public class ActivityPubManager implements ActivityListener, NotificationListene
 
     private void activityToFollowers(User user, Actor from, Activity activity) {
         socialService.getFollowers(user).forEach(acct -> {
-            var context = signatureManager.getContext(URI.create(acct));
+            var context = activityPubService.get(URI.create(acct));
             context.ifPresentOrElse((follower) -> {
                 if (follower instanceof Actor) {
                     var to = (Actor) follower;
                     try {
-                        signatureManager.post(from, to, activity);
+                        activityPubService.post(from, to, activity);
                     } catch (Exception e) {
                         logger.warn("Delivery to {} failed: {}", to, e.getMessage());
                     }
@@ -251,7 +255,7 @@ public class ActivityPubManager implements ActivityListener, NotificationListene
         subscribers.addAll(note.getCc());
         subscribers.forEach(acct -> {
             if (!acct.equals(profileUriBuilder.followersUri(user))) {
-                var context = signatureManager.getContext(URI.create(acct));
+                var context = activityPubService.get(URI.create(acct));
                 context.ifPresentOrElse((follower) -> {
                     if (follower instanceof Actor) {
                         var to = (Actor) follower;
@@ -261,7 +265,7 @@ public class ActivityPubManager implements ActivityListener, NotificationListene
                         create.setPublished(note.getPublished());
                         create.setObject(note);
                         try {
-                            signatureManager.post(me, to, create);
+                            activityPubService.post(me, to, create);
                         } catch (IOException | NoSuchAlgorithmException e) {
                             logger.warn("Delivery to {} failed: {}", to, e.getMessage());
                         }
@@ -308,10 +312,10 @@ public class ActivityPubManager implements ActivityListener, NotificationListene
         note.setTags(msg.getTags().stream().map(t -> new Hashtag(profileUriBuilder.tagUri(t), t.getName()))
                 .collect(Collectors.toList()));
         if (msg.getReplyToUri() != null && msg.getReplyToUri().toASCIIString().length() > 0) {
-            Optional<Context> noteContext = signatureManager.getContext(msg.getReplyToUri());
+            Optional<Context> noteContext = activityPubService.get(msg.getReplyToUri());
             if (noteContext.isPresent()) {
                 Note activity = (Note) noteContext.get();
-                Optional<Context> personContext = signatureManager.getContext(URI.create(activity.getAttributedTo()));
+                Optional<Context> personContext = activityPubService.get(URI.create(activity.getAttributedTo()));
                 if (personContext.isPresent()) {
                     Actor person = (Actor) personContext.get();
                     note.getTags().add(new Mention(person.getUrl(), person.getPreferredUsername()));
@@ -324,13 +328,17 @@ public class ActivityPubManager implements ActivityListener, NotificationListene
         }
         MessageUtils.getGlobalMentions(msg).forEach(m -> {
             // @user@server.tld -> user@server.tld
-            Optional<Context> personContext = signatureManager.discoverPerson(m.substring(1));
-            if (personContext.isPresent()) {
-                Actor person = (Actor) personContext.get();
-                note.getTags().add(new Mention(person.getUrl(), person.getPreferredUsername()));
-                List<String> cc = new ArrayList<>(note.getCc());
-                cc.add(person.getId());
-                note.setCc(cc);
+            var personURI = webfingerService.discoverAccountURI(m.substring(1),
+                    MediaType.valueOf(Context.ACTIVITY_MEDIA_TYPE));
+            if (!personURI.toASCIIString().isEmpty()) {
+                var personContext = activityPubService.get(personURI);
+                if (personContext.isPresent()) {
+                    Actor person = (Actor) personContext.get();
+                    note.getTags().add(new Mention(person.getUrl(), person.getPreferredUsername()));
+                    List<String> cc = new ArrayList<>(note.getCc());
+                    cc.add(person.getId());
+                    note.setCc(cc);
+                }
             }
         });
         note.setSensitive(MessageUtils.isSensitive(msg));
@@ -371,7 +379,7 @@ public class ActivityPubManager implements ActivityListener, NotificationListene
     }
 
     public User actorToUser(URI uri) throws HttpBadRequestException, JsonProcessingException {
-        var context = signatureManager.getContext(uri);
+        var context = activityPubService.get(uri);
         if (context.isPresent() && context.get() instanceof Actor actor) {
             User user = new User();
             user.setUri(URI.create(actor.getId()));
diff --git a/src/main/java/com/juick/SignatureManager.java b/src/main/java/com/juick/SignatureManager.java
deleted file mode 100644
index 792cc8cd..00000000
--- a/src/main/java/com/juick/SignatureManager.java
+++ /dev/null
@@ -1,200 +0,0 @@
-/*
- * Copyright (C) 2008-2022, Juick
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Affero General Public License as
- * published by the Free Software Foundation, either version 3 of the
- * License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Affero General Public License for more details.
- *
- * You should have received a copy of the GNU Affero General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-package com.juick;
-
-import com.fasterxml.jackson.databind.ObjectMapper;
-import com.juick.model.AnonymousUser;
-import com.juick.model.User;
-import com.juick.service.UserService;
-import com.juick.service.activities.DeleteUserEvent;
-import com.juick.util.DateFormattersHolder;
-import com.juick.www.api.activity.model.Context;
-import com.juick.www.api.activity.model.objects.Actor;
-import com.juick.www.api.webfinger.model.Account;
-import com.juick.www.api.webfinger.model.Link;
-import org.apache.commons.lang3.StringUtils;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.cache.annotation.Cacheable;
-import org.springframework.context.ApplicationEventPublisher;
-import org.springframework.http.*;
-import org.springframework.web.client.RestClientException;
-import org.springframework.web.client.RestTemplate;
-import org.springframework.web.util.UriComponentsBuilder;
-import org.tomitribe.auth.signatures.Base64;
-import org.tomitribe.auth.signatures.*;
-import rocks.xmpp.addr.Jid;
-
-import javax.inject.Inject;
-import java.io.IOException;
-import java.net.URI;
-import java.security.Key;
-import java.security.MessageDigest;
-import java.security.NoSuchAlgorithmException;
-import java.security.SignatureException;
-import java.time.Instant;
-import java.util.*;
-
-import static com.juick.www.api.activity.model.Context.ACTIVITY_MEDIA_TYPE;
-
-public class SignatureManager {
-    private static final Logger logger = LoggerFactory.getLogger("ActivityPub");
-    @Inject
-    private KeystoreManager keystoreManager;
-    @Inject
-    private ObjectMapper jsonMapper;
-    @Inject
-    private UserService userService;
-    @Inject
-    private RestTemplate apClient;
-    @Inject
-    private ApplicationEventPublisher applicationEventPublisher;
-
-    public void post(Actor from, Actor to, Context data) throws IOException, NoSuchAlgorithmException {
-        UriComponentsBuilder uriComponentsBuilder = UriComponentsBuilder.fromUriString(to.getInbox());
-        URI inbox = uriComponentsBuilder.build().toUri();
-        Instant now = Instant.now();
-        String requestDate = DateFormattersHolder.getHttpDateFormatter().format(now);
-        String host = inbox.getPort() > 0 ? String.format("%s:%d", inbox.getHost(), inbox.getPort()) : inbox.getHost();
-        var finalContext = Context.build(data);
-        var payload = jsonMapper.writeValueAsString(finalContext);
-        final byte[] digest = MessageDigest.getInstance("SHA-256").digest(payload.getBytes()); // (1)
-        final String digestHeader = "SHA-256=" + new String(Base64.encodeBase64(digest));
-        String signatureString = addSignature(from, host, "POST", inbox.getPath(), requestDate, digestHeader);
-
-        HttpHeaders requestHeaders = new HttpHeaders();
-        requestHeaders.add("Content-Type", Context.ACTIVITYSTREAMS_PROFILE_MEDIA_TYPE);
-        requestHeaders.add("Date", requestDate);
-        requestHeaders.add("Host", host);
-        requestHeaders.add("Digest", digestHeader);
-        requestHeaders.add("Signature", signatureString);
-        HttpEntity<String> request = new HttpEntity<>(payload, requestHeaders);
-        logger.debug("Sending context to {}: {}", to.getId(), payload);
-        ResponseEntity<Void> response = apClient.postForEntity(inbox, request, Void.class);
-        logger.debug("Remote response: {}", response.getStatusCode());
-    }
-
-    public String addSignature(Actor from, String host, String method, String path, String dateString,
-            String digestHeader) throws IOException {
-        return addSignature(from, host, method, path, dateString, digestHeader, keystoreManager);
-    }
-
-    public String addSignature(Actor from, String host, String method, String path, String dateString,
-            String digestHeader, KeystoreManager keystoreManager) throws IOException {
-        List<String> requiredHeaders = StringUtils.isEmpty(digestHeader)
-                ? Arrays.asList("(request-target)", "host", "date")
-                : Arrays.asList("(request-target)", "host", "date", "digest");
-        Signature templateSignature = new Signature(from.getPublicKey().getId(), "rsa-sha256", null, requiredHeaders);
-        Map<String, String> headers = new HashMap<>();
-        headers.put("host", host);
-        headers.put("date", dateString);
-        if (StringUtils.isNotEmpty(digestHeader)) {
-            headers.put("digest", digestHeader);
-        }
-        Signer signer = new Signer(keystoreManager.getPrivateKey(), templateSignature);
-        Signature signature = signer.sign(method, path, headers);
-        // remove "Signature: " from result
-        return signature.toString().substring(10);
-    }
-
-    public User verifySignature(String method, String path, Map<String, String> headers) {
-        String signatureString = headers.get("signature");
-        Signature signature = Signature.fromString(signatureString);
-        var keyId = UriComponentsBuilder.fromUriString(signature.getKeyId()).fragment(null).build().toUri();
-        var context = getContext(keyId);
-        if (context.isPresent() && context.get() instanceof Actor actor) {
-            Key key = KeystoreManager.publicKeyOf(actor);
-            if (key != null) {
-                Verifier verifier = new Verifier(key, signature);
-                try {
-                    boolean result = verifier.verify(method, path, headers);
-                    if (result) {
-                        User user = new User();
-                        user.setUri(URI.create(actor.getId()));
-                        if (key.equals(keystoreManager.getPublicKey())) {
-                            return userService.getUserByName(actor.getName());
-                        }
-                        if (actor.isSuspended()) {
-                            logger.info("{} is suspended, deleting", actor.getId());
-                            applicationEventPublisher.publishEvent(new DeleteUserEvent(this, actor.getId()));
-                        }
-                        return user;
-                    } else {
-                        return AnonymousUser.INSTANCE;
-                    }
-                } catch (NoSuchAlgorithmException | SignatureException | MissingRequiredHeaderException
-                        | IOException e) {
-                    logger.warn("Verification error for {}: {}", signature.getKeyId(), e.getMessage());
-                }
-            } else {
-                logger.warn("Public key missing for {}", actor.getId());
-            }
-        } else {
-            logger.warn("Public key error for {}", signature.getKeyId());
-        }
-        return AnonymousUser.INSTANCE;
-    }
-
-    @Cacheable("profiles")
-    public Optional<Context> getContext(URI contextUri) {
-        try {
-            HttpHeaders headers = new HttpHeaders();
-            headers.setAccept(Collections.singletonList(MediaType.valueOf(ACTIVITY_MEDIA_TYPE)));
-            HttpEntity<Void> activityRequest = new HttpEntity<>(headers);
-            var response = apClient.exchange(contextUri, HttpMethod.GET, activityRequest, Context.class);
-            if (response.getStatusCode().is2xxSuccessful() && response.hasBody()) {
-                var context = response.getBody();
-                if (context == null) {
-                    logger.warn("Cannot identify {}", contextUri);
-                    return Optional.empty();
-                }
-                return Optional.of(context);
-            }
-        } catch (Exception e) {
-            logger.warn("{}", e.getMessage());
-        }
-        return Optional.empty();
-    }
-
-    public Optional<Context> discoverPerson(String acct) {
-        Jid acctId = Jid.of(acct);
-        URI resourceUri = UriComponentsBuilder.fromPath("/.well-known/webfinger").host(acctId.getDomain())
-                .scheme("https").queryParam("resource", "acct:" + acct).build().toUri();
-        HttpHeaders headers = new HttpHeaders();
-        headers.setAccept(Collections.singletonList(MediaType.valueOf("application/jrd+json")));
-        HttpEntity<Void> webfingerRequest = new HttpEntity<>(headers);
-        try {
-            ResponseEntity<Account> response = apClient.exchange(resourceUri, HttpMethod.GET, webfingerRequest,
-                    Account.class);
-            if (response.getStatusCode().is2xxSuccessful()) {
-                Account acctData = response.getBody();
-                if (acctData != null) {
-                    for (Link l : acctData.links()) {
-                        if (l.rel().equals("self") && l.type().equals(ACTIVITY_MEDIA_TYPE)) {
-                            return getContext(URI.create(l.href()));
-                        }
-                    }
-                }
-            }
-        } catch (RestClientException e) {
-            logger.warn("Cannot discover person {}: {}", acct, e.getMessage());
-            return Optional.empty();
-        }
-        return Optional.empty();
-    }
-}
diff --git a/src/main/java/com/juick/config/ActivityPubClientConfig.java b/src/main/java/com/juick/config/ActivityPubClientConfig.java
new file mode 100644
index 00000000..940071e7
--- /dev/null
+++ b/src/main/java/com/juick/config/ActivityPubClientConfig.java
@@ -0,0 +1,61 @@
+package com.juick.config;
+
+import java.nio.charset.StandardCharsets;
+
+import javax.inject.Inject;
+
+import org.apache.hc.client5.http.impl.classic.CloseableHttpClient;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.core.convert.ConversionService;
+import org.springframework.http.client.ClientHttpRequestFactory;
+import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
+import org.springframework.http.converter.StringHttpMessageConverter;
+import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
+import org.springframework.web.client.RestTemplate;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.juick.model.User;
+import com.juick.service.SignatureService;
+import com.juick.util.ActivityPubRequestInterceptor;
+import com.juick.www.api.activity.model.objects.Actor;
+
+@Configuration
+public class ActivityPubClientConfig {
+    @Inject
+    CloseableHttpClient httpClient;
+    @Inject
+    ObjectMapper jsonMapper;
+    @Inject
+    private ActivityPubClientErrorHandler activityPubClientErrorHandler;
+    @Inject
+    private SignatureService signatureService;
+    @Inject
+    private ConversionService conversionService;
+    @Inject
+    private User serviceUser;
+
+    @Bean
+    ClientHttpRequestFactory clientHttpRequestFactory() {
+        var clientHttpRequestFactory = new HttpComponentsClientHttpRequestFactory();
+        clientHttpRequestFactory.setHttpClient(httpClient);
+        return clientHttpRequestFactory;
+    }
+
+    @Bean
+    MappingJackson2HttpMessageConverter mappingJacksonHttpMessageConverter() {
+        MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter();
+        converter.setObjectMapper(jsonMapper);
+        return converter;
+    }
+
+    @Bean
+    RestTemplate restClient() {
+        RestTemplate restTemplate = new RestTemplate(clientHttpRequestFactory());
+        restTemplate.getMessageConverters().add(0, mappingJacksonHttpMessageConverter());
+        restTemplate.getMessageConverters().add(0, new StringHttpMessageConverter(StandardCharsets.UTF_8));
+        restTemplate.setErrorHandler(activityPubClientErrorHandler);
+        restTemplate.getInterceptors().add(new ActivityPubRequestInterceptor());
+        return restTemplate;
+    }
+}
diff --git a/src/main/java/com/juick/config/ActivityPubClientErrorHandler.java b/src/main/java/com/juick/config/ActivityPubClientErrorHandler.java
index 243a4e32..b3aedf1f 100644
--- a/src/main/java/com/juick/config/ActivityPubClientErrorHandler.java
+++ b/src/main/java/com/juick/config/ActivityPubClientErrorHandler.java
@@ -18,7 +18,6 @@
 package com.juick.config;
 
 import com.juick.service.activities.DeleteUserEvent;
-import org.apache.commons.io.IOUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.context.ApplicationEventPublisher;
diff --git a/src/main/java/com/juick/config/ActivityPubConfig.java b/src/main/java/com/juick/config/ActivityPubConfig.java
index 9a626d12..b18dc71c 100644
--- a/src/main/java/com/juick/config/ActivityPubConfig.java
+++ b/src/main/java/com/juick/config/ActivityPubConfig.java
@@ -20,29 +20,18 @@ package com.juick.config;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.juick.ActivityPubManager;
 import com.juick.KeystoreManager;
-import com.juick.util.ActivityPubRequestInterceptor;
 import com.juick.www.WebApp;
 import com.juick.www.api.activity.converters.UserToActorConverter;
 
 import com.juick.www.api.activity.helpers.ProfileUriBuilder;
-import org.apache.hc.client5.http.impl.classic.CloseableHttpClient;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
-import org.springframework.http.client.ClientHttpRequestFactory;
-import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
-import org.springframework.http.converter.StringHttpMessageConverter;
-import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
-import org.springframework.web.client.RestTemplate;
 import javax.inject.Inject;
 
-import java.nio.charset.StandardCharsets;
-
 @Configuration
 public class ActivityPubConfig {
     @Inject
-    ActivityPubClientErrorHandler activityPubClientErrorHandler;
-    @Inject
     ObjectMapper jsonMapper;
     @Inject
     KeystoreManager keystoreManager;
@@ -52,37 +41,10 @@ public class ActivityPubConfig {
     private String baseUri;
 
     @Bean
-    MappingJackson2HttpMessageConverter mappingJacksonHttpMessageConverter() {
-        MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter();
-        converter.setObjectMapper(jsonMapper);
-        return converter;
-    }
-
-    @Bean
     ActivityPubManager activityPubManager() {
         return new ActivityPubManager();
     }
 
-    @Inject
-    CloseableHttpClient httpClient;
-
-    @Bean
-    ClientHttpRequestFactory clientHttpRequestFactory() {
-        var clientHttpRequestFactory = new HttpComponentsClientHttpRequestFactory();
-        clientHttpRequestFactory.setHttpClient(httpClient);
-        return clientHttpRequestFactory;
-    }
-
-    @Bean
-    RestTemplate apClient() {
-        RestTemplate restTemplate = new RestTemplate(clientHttpRequestFactory());
-        restTemplate.getMessageConverters().add(0, mappingJacksonHttpMessageConverter());
-        restTemplate.getMessageConverters().add(0, new StringHttpMessageConverter(StandardCharsets.UTF_8));
-        restTemplate.setErrorHandler(activityPubClientErrorHandler);
-        restTemplate.getInterceptors().add(new ActivityPubRequestInterceptor());
-        return restTemplate;
-    }
-
     @Bean
     UserToActorConverter userToActorConverter() {
         return new UserToActorConverter(profileUriBuilder(), keystoreManager, webApp);
diff --git a/src/main/java/com/juick/config/AppConfig.java b/src/main/java/com/juick/config/AppConfig.java
index d54bc675..ff92de1f 100644
--- a/src/main/java/com/juick/config/AppConfig.java
+++ b/src/main/java/com/juick/config/AppConfig.java
@@ -20,6 +20,7 @@ package com.juick.config;
 import com.juick.*;
 import com.juick.model.User;
 import com.juick.service.HelpService;
+import com.juick.service.SignatureService;
 import com.juick.service.StorageService;
 import com.juick.service.FileSystemStorageService;
 import com.juick.service.UserService;
@@ -158,8 +159,8 @@ public class AppConfig {
     }
 
     @Bean
-    SignatureManager signatureManager() {
-        return new SignatureManager();
+    SignatureService signatureManager() {
+        return new SignatureService(keystoreManager());
     }
 
     @Bean
diff --git a/src/main/java/com/juick/config/SecurityConfig.java b/src/main/java/com/juick/config/SecurityConfig.java
index d60abe00..d3f89eef 100644
--- a/src/main/java/com/juick/config/SecurityConfig.java
+++ b/src/main/java/com/juick/config/SecurityConfig.java
@@ -18,7 +18,7 @@
 package com.juick.config;
 
 import com.juick.KeystoreManager;
-import com.juick.SignatureManager;
+import com.juick.service.ActivityPubService;
 import com.juick.service.UserService;
 import com.juick.service.security.BearerTokenAuthenticationFilter;
 import com.juick.service.security.HTTPSignatureAuthenticationFilter;
@@ -30,8 +30,6 @@ import com.nimbusds.jose.jwk.RSAKey;
 import com.nimbusds.jose.jwk.source.ImmutableJWKSet;
 import com.nimbusds.jose.jwk.source.JWKSource;
 import com.nimbusds.jose.proc.SecurityContext;
-import jakarta.servlet.http.HttpServletRequest;
-import jakarta.servlet.http.HttpServletResponse;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
@@ -53,7 +51,6 @@ import org.springframework.security.oauth2.server.authorization.config.annotatio
 import org.springframework.security.oauth2.server.authorization.config.annotation.web.configurers.OAuth2AuthorizationServerConfigurer;
 import org.springframework.security.oauth2.server.authorization.settings.AuthorizationServerSettings;
 import org.springframework.security.web.AuthenticationEntryPoint;
-import org.springframework.security.web.RedirectStrategy;
 import org.springframework.security.web.SecurityFilterChain;
 import org.springframework.security.web.authentication.*;
 import org.springframework.security.web.authentication.rememberme.TokenBasedRememberMeServices;
@@ -65,7 +62,6 @@ import org.springframework.web.cors.CorsConfigurationSource;
 import org.springframework.web.cors.UrlBasedCorsConfigurationSource;
 
 import javax.inject.Inject;
-import java.io.IOException;
 import java.security.interfaces.RSAPrivateKey;
 import java.security.interfaces.RSAPublicKey;
 import java.util.Arrays;
@@ -107,7 +103,7 @@ public class SecurityConfig {
     }
 
     @Inject
-    private SignatureManager signatureManager;
+    private ActivityPubService activityPubService;
 
     @Bean
     HashParamAuthenticationFilter apiAuthenticationFilter() {
@@ -195,11 +191,11 @@ public class SecurityConfig {
     }
 
     @Bean
-    @Order(2)
+    @Order(Ordered.HIGHEST_PRECEDENCE + 1)
     SecurityFilterChain apiChain(HttpSecurity http) throws Exception {
-        http.securityMatcher("/api/**")
+        http.securityMatcher("/api/**", "/u/**", "/n/**")
                 .addFilterBefore(apiAuthenticationFilter(), BasicAuthenticationFilter.class)
-                .addFilterBefore(new HTTPSignatureAuthenticationFilter(signatureManager, userService),
+                .addFilterBefore(new HTTPSignatureAuthenticationFilter(activityPubService, userService),
                         BasicAuthenticationFilter.class)
                 .authorizeHttpRequests(requests -> requests
                         .requestMatchers(HttpMethod.OPTIONS).permitAll()
@@ -210,7 +206,7 @@ public class SecurityConfig {
                                 "/api/skypebotendpoint", "/api/_fblogin",
                                 "/api/_vklogin", "/api/_tglogin",
                                 "/api/_google", "/api/_applelogin", "/api/signup",
-                                "/api/inbox", "/api/events", "/api/u/",
+                                "/api/inbox", "/api/events", "/u/**", "/n/**",
                                 "/api/info/**", "/api/v1/apps", "/api/v1/instance",
                                 "/api/nodeinfo/2.0", "/oauth/**")
                         .permitAll()
@@ -251,6 +247,7 @@ public class SecurityConfig {
         return handler;
     }
     @Bean
+    @Order(Ordered.HIGHEST_PRECEDENCE + 2)
     SecurityFilterChain wwwChain(HttpSecurity http) throws Exception {
         http.addFilterBefore(wwwAuthenticationFilter(), BasicAuthenticationFilter.class)
                 .authorizeHttpRequests(authorize -> authorize
diff --git a/src/main/java/com/juick/service/ActivityPubService.java b/src/main/java/com/juick/service/ActivityPubService.java
index c45b0c13..f161be7b 100644
--- a/src/main/java/com/juick/service/ActivityPubService.java
+++ b/src/main/java/com/juick/service/ActivityPubService.java
@@ -18,24 +18,71 @@
 package com.juick.service;
 
 import com.juick.model.User;
+import com.juick.service.activities.DeleteUserEvent;
+import com.juick.util.DateFormattersHolder;
+import com.juick.www.api.activity.model.Context;
+import com.juick.www.api.activity.model.objects.Actor;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.juick.KeystoreManager;
 import com.juick.model.AnonymousUser;
+
+import org.apache.commons.codec.binary.Base64;
+import org.apache.commons.lang3.StringUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Value;
+import org.springframework.cache.annotation.Cacheable;
+import org.springframework.context.ApplicationEventPublisher;
+import org.springframework.core.convert.ConversionService;
 import org.springframework.dao.DuplicateKeyException;
+import org.springframework.http.*;
 import org.springframework.stereotype.Repository;
 import org.springframework.transaction.annotation.Transactional;
+import org.springframework.web.client.RestTemplate;
 import org.springframework.web.util.UriComponents;
 import org.springframework.web.util.UriComponentsBuilder;
+import org.tomitribe.auth.signatures.MissingRequiredHeaderException;
+import org.tomitribe.auth.signatures.Signature;
+import org.tomitribe.auth.signatures.Verifier;
 
 import javax.annotation.Nonnull;
 import javax.inject.Inject;
+
+import java.io.IOException;
+import java.net.URI;
+import java.security.Key;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.security.SignatureException;
+import java.time.Instant;
+import java.util.Collections;
 import java.util.List;
+import java.util.Map;
+import java.util.Optional;
 
 @Repository
 public class ActivityPubService extends BaseJdbcService implements SocialService {
+
+    private static final Logger logger = LoggerFactory.getLogger("ActivityPub");
+
     @Value("${ap_base_uri:http://localhost:8080/}")
     private String baseUri;
     @Inject
     private UserService userService;
+    @Inject
+    private RestTemplate restClient;
+    @Inject
+    private ObjectMapper jsonMapper;
+    @Inject
+    private SignatureService signatureService;
+    @Inject
+    private ApplicationEventPublisher applicationEventPublisher;
+    @Inject
+    private KeystoreManager keystoreManager;
+    @Inject
+    private User serviceUser;
+    @Inject
+    private ConversionService conversionService;
 
     @Transactional(readOnly = true)
     @Override
@@ -53,7 +100,8 @@ public class ActivityPubService extends BaseJdbcService implements SocialService
     @Transactional(readOnly = true)
     @Override
     public @Nonnull List<String> getFollowers(User user) {
-        return getJdbcTemplate().queryForList("SELECT acct FROM followers WHERE user_id=?", String.class, user.getUid());
+        return getJdbcTemplate().queryForList("SELECT acct FROM followers WHERE user_id=?", String.class,
+                user.getUid());
     }
 
     @Transactional
@@ -78,4 +126,112 @@ public class ActivityPubService extends BaseJdbcService implements SocialService
     public void removeAccount(String acct) {
         getJdbcTemplate().update("DELETE FROM followers WHERE acct=?", acct);
     }
+
+    @Cacheable("profiles")
+    public Optional<Context> get(URI contextUri) {
+        Instant now = Instant.now();
+        String requestDate = DateFormattersHolder.getHttpDateFormatter().format(now);
+        String host = contextUri.getPort() > 0 ? String.format("%s:%d", contextUri.getHost(), contextUri.getPort())
+                : contextUri.getHost();
+        var from = conversionService.convert(serviceUser, Actor.class);
+        try {
+            String signatureString = signatureService.addSignature(from, host, "get", contextUri.getPath(), requestDate,
+                    "");
+            HttpHeaders requestHeaders = new HttpHeaders();
+            requestHeaders.add("Date", requestDate);
+            requestHeaders.add("Host", host);
+            requestHeaders.add("Signature", signatureString);
+            requestHeaders.setAccept(Collections.singletonList(MediaType.valueOf(Context.ACTIVITY_MEDIA_TYPE)));
+            HttpEntity<Void> activityRequest = new HttpEntity<>(requestHeaders);
+            var response = restClient.exchange(contextUri, HttpMethod.GET, activityRequest, Context.class);
+            if (response.getStatusCode().is2xxSuccessful()) {
+                var context = response.getBody();
+                if (context == null) {
+                    logger.warn("Cannot identify {}", contextUri);
+                    return Optional.empty();
+                }
+                return Optional.of(context);
+            }
+        } catch (IOException e) {
+            logger.warn("HTTP Signature exception: {}", e.getMessage());
+        }
+        return Optional.empty();
+    }
+
+    public HttpStatusCode post(Actor from, Actor to, Context data) throws IOException, NoSuchAlgorithmException {
+        UriComponentsBuilder uriComponentsBuilder = UriComponentsBuilder.fromUriString(to.getInbox());
+        URI inbox = uriComponentsBuilder.build().toUri();
+        Instant now = Instant.now();
+        String requestDate = DateFormattersHolder.getHttpDateFormatter().format(now);
+        String host = inbox.getPort() > 0 ? String.format("%s:%d", inbox.getHost(), inbox.getPort()) : inbox.getHost();
+        var finalContext = Context.build(data);
+        var payload = jsonMapper.writeValueAsString(finalContext);
+        final byte[] digest = MessageDigest.getInstance("SHA-256").digest(payload.getBytes()); // (1)
+        final String digestHeader = "SHA-256=" + new String(Base64.encodeBase64(digest));
+        String signatureString = signatureService.addSignature(from, host, "post", inbox.getPath(), requestDate,
+                digestHeader);
+
+        HttpHeaders requestHeaders = new HttpHeaders();
+        requestHeaders.add("Content-Type", Context.ACTIVITYSTREAMS_PROFILE_MEDIA_TYPE);
+        requestHeaders.add("Date", requestDate);
+        requestHeaders.add("Host", host);
+        requestHeaders.add("Digest", digestHeader);
+        requestHeaders.add("Signature", signatureString);
+        HttpEntity<String> request = new HttpEntity<>(payload, requestHeaders);
+        logger.debug("Sending context to {}: {}", to.getId(), payload);
+        ResponseEntity<String> response = restClient.postForEntity(inbox, request, String.class);
+        logger.debug("Remote response: {} {}", response.getStatusCode(), response.getBody());
+        return response.getStatusCode();
+    }
+
+    public User verifyActor(String method, String path, Map<String, String> headers) {
+        String signatureString = headers.get("signature");
+        if (StringUtils.isNotEmpty(signatureString)) {
+            try {
+                Signature signature = Signature.fromString(signatureString);
+                var keyId = UriComponentsBuilder.fromUriString(signature.getKeyId()).fragment(null).build().toUri();
+                var user = getUserByAccountUri(keyId.toASCIIString());
+                Key key = null;
+                Actor actor = null;
+                if (!user.isAnonymous()) {
+                    // local user
+                    key = keystoreManager.getPublicKey();
+                } else {
+                    var context = get(keyId);
+                    if (context.isPresent()) {
+                        actor = (Actor) context.get();
+                        key = KeystoreManager.publicKeyOf(actor);
+                    }
+                }
+                if (key != null) {
+                    Verifier verifier = new Verifier(key, signature);
+                    try {
+                        boolean result = verifier.verify(method.toLowerCase(), path, headers);
+                        if (result) {
+                            if (!user.isAnonymous()) {
+                                return user;
+                            } else {
+                                if (actor != null) {
+                                    User person = new User();
+                                    person.setUri(URI.create(actor.getId()));
+                                    if (actor.isSuspended()) {
+                                        logger.info("{} is suspended, deleting", actor.getId());
+                                        applicationEventPublisher
+                                                .publishEvent(new DeleteUserEvent(this, actor.getId()));
+                                    }
+                                    return person;
+                                }
+                            }
+                        }
+                    } catch (NoSuchAlgorithmException | SignatureException | MissingRequiredHeaderException
+                            | IOException e) {
+                        logger.warn("Verification error for {}: {}", signature.getKeyId(), e.getMessage());
+                    }
+                }
+            } catch (Exception ex) {
+
+            }
+        }
+        return AnonymousUser.INSTANCE;
+    }
 }
diff --git a/src/main/java/com/juick/service/SignatureService.java b/src/main/java/com/juick/service/SignatureService.java
new file mode 100644
index 00000000..12d9d67b
--- /dev/null
+++ b/src/main/java/com/juick/service/SignatureService.java
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2008-2022, Juick
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.juick.service;
+
+import com.juick.KeystoreManager;
+import com.juick.www.api.activity.model.objects.Actor;
+import org.apache.commons.lang3.StringUtils;
+import org.tomitribe.auth.signatures.*;
+import java.io.IOException;
+import java.util.*;
+
+public class SignatureService {
+    
+    private KeystoreManager keystoreManager;
+
+    public SignatureService(KeystoreManager keystoreManager) {
+        this.keystoreManager = keystoreManager;
+    }
+
+    public String addSignature(Actor from, String host, String method, String path, String dateString,
+            String digestHeader) throws IOException {
+        return addSignature(from, host, method, path, dateString, digestHeader, keystoreManager);
+    }
+
+    public String addSignature(Actor from, String host, String method, String path, String dateString,
+            String digestHeader, KeystoreManager keystoreManager) throws IOException {
+        List<String> requiredHeaders = StringUtils.isEmpty(digestHeader)
+                ? Arrays.asList("(request-target)", "host", "date")
+                : Arrays.asList("(request-target)", "host", "date", "digest");
+        Signature templateSignature = new Signature(from.getPublicKey().getId(), "rsa-sha256", null, requiredHeaders);
+        Map<String, String> headers = new HashMap<>();
+        headers.put("host", host);
+        headers.put("date", dateString);
+        if (StringUtils.isNotEmpty(digestHeader)) {
+            headers.put("digest", digestHeader);
+        }
+        Signer signer = new Signer(keystoreManager.getPrivateKey(), templateSignature);
+        Signature signature = signer.sign(method.toLowerCase(), path, headers);
+        // remove "Signature: " from result
+        return signature.toString().substring(10);
+    }
+}
diff --git a/src/main/java/com/juick/service/WebfingerService.java b/src/main/java/com/juick/service/WebfingerService.java
new file mode 100644
index 00000000..dc978763
--- /dev/null
+++ b/src/main/java/com/juick/service/WebfingerService.java
@@ -0,0 +1,58 @@
+package com.juick.service;
+
+import java.net.URI;
+import java.util.Collections;
+
+import javax.inject.Inject;
+
+import org.apache.commons.lang3.StringUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.http.HttpEntity;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.stereotype.Component;
+import org.springframework.web.client.RestClientException;
+import org.springframework.web.client.RestTemplate;
+import org.springframework.web.util.UriComponentsBuilder;
+
+import com.juick.www.api.webfinger.model.Account;
+import com.juick.www.api.webfinger.model.Link;
+
+import rocks.xmpp.addr.Jid;
+
+@Component
+public class WebfingerService {
+    private static final Logger logger = LoggerFactory.getLogger("ActivityPub");
+
+    private final RestTemplate restClient;
+    @Inject
+    public WebfingerService(final RestTemplate restClient) {
+        this.restClient = restClient;
+    }
+    public URI discoverAccountURI(String acct, MediaType linkType) {
+        Jid acctId = Jid.of(acct);
+        URI resourceUri = UriComponentsBuilder.fromPath("/.well-known/webfinger").host(acctId.getDomain())
+                .scheme("https").queryParam("resource", "acct:" + acct).build().toUri();
+        HttpHeaders headers = new HttpHeaders();
+        headers.setAccept(Collections.singletonList(MediaType.valueOf("application/jrd+json")));
+        HttpEntity<Void> webfingerRequest = new HttpEntity<>(headers);
+        try {
+            ResponseEntity<Account> response = restClient.exchange(resourceUri, HttpMethod.GET, webfingerRequest,
+                    Account.class);
+            if (response.getStatusCode().is2xxSuccessful()) {
+                var account = response.getBody();
+                for (Link l : account.links()) {
+                    if (l.rel().equals("self") && l.type().equals(linkType.toString())) {
+                        return URI.create(l.href());
+                    }
+                }
+            }
+        } catch (RestClientException e) {
+            logger.warn("Cannot discover person {}: {}", acct, e.getMessage());
+        }
+        return URI.create(StringUtils.EMPTY);
+    }
+}
diff --git a/src/main/java/com/juick/service/security/BearerTokenAuthenticationFilter.java b/src/main/java/com/juick/service/security/BearerTokenAuthenticationFilter.java
index 2e96a594..f4e73b12 100644
--- a/src/main/java/com/juick/service/security/BearerTokenAuthenticationFilter.java
+++ b/src/main/java/com/juick/service/security/BearerTokenAuthenticationFilter.java
@@ -19,7 +19,6 @@ package com.juick.service.security;
 
 import com.juick.service.UserService;
 import com.juick.service.security.entities.JuickUser;
-import io.jsonwebtoken.Claims;
 import io.jsonwebtoken.JwtParser;
 import io.jsonwebtoken.Jwts;
 import jakarta.servlet.FilterChain;
@@ -52,9 +51,9 @@ public class BearerTokenAuthenticationFilter extends BaseAuthenticationFilter {
     }
 
     @Override
-    protected void doFilterInternal(@Nonnull HttpServletRequest request,
-                                    @Nonnull HttpServletResponse response,
-                                    @Nonnull FilterChain filterChain) throws ServletException, IOException {
+    protected void doFilterInternal(HttpServletRequest request,
+                                    HttpServletResponse response,
+                                    FilterChain filterChain) throws ServletException, IOException {
         if (authenticationIsRequired()) {
             var headers = Collections.list(request.getHeaderNames())
                     .stream()
diff --git a/src/main/java/com/juick/service/security/HTTPSignatureAuthenticationFilter.java b/src/main/java/com/juick/service/security/HTTPSignatureAuthenticationFilter.java
index 5f6a730e..a851ef36 100644
--- a/src/main/java/com/juick/service/security/HTTPSignatureAuthenticationFilter.java
+++ b/src/main/java/com/juick/service/security/HTTPSignatureAuthenticationFilter.java
@@ -17,8 +17,8 @@
 
 package com.juick.service.security;
 
-import com.juick.SignatureManager;
 import com.juick.model.User;
+import com.juick.service.ActivityPubService;
 import com.juick.service.UserService;
 import com.juick.service.security.entities.JuickUser;
 import jakarta.servlet.FilterChain;
@@ -31,7 +31,6 @@ import org.springframework.security.authentication.UsernamePasswordAuthenticatio
 import org.springframework.security.core.Authentication;
 import org.springframework.security.core.context.SecurityContextHolder;
 
-import javax.annotation.Nonnull;
 import java.io.IOException;
 import java.util.Collections;
 import java.util.Map;
@@ -39,39 +38,37 @@ import java.util.stream.Collectors;
 
 public class HTTPSignatureAuthenticationFilter extends BaseAuthenticationFilter {
 
-    private final SignatureManager signatureManager;
+    private final ActivityPubService signatureManager;
     private final UserService userService;
 
     public HTTPSignatureAuthenticationFilter(
-            final SignatureManager signatureManager,
+            final ActivityPubService activityPubService,
             final UserService userService) {
-        this.signatureManager = signatureManager;
+        this.signatureManager = activityPubService;
         this.userService = userService;
     }
 
     @Override
-    protected void doFilterInternal(@Nonnull HttpServletRequest request, @Nonnull HttpServletResponse response,
-                                    @Nonnull FilterChain filterChain) throws IOException, ServletException {
+    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response,
+            FilterChain filterChain) throws IOException, ServletException {
         if (authenticationIsRequired()) {
             Map<String, String> headers = Collections.list(request.getHeaderNames())
                     .stream()
                     .collect(Collectors.toMap(String::toLowerCase, request::getHeader));
-            if (StringUtils.isNotEmpty(headers.get("signature"))) {
-                User user = signatureManager.verifySignature(request.getMethod(), request.getRequestURI(), headers);
-                String userUri = user.getUri().toString();
-                if (!user.isAnonymous() || userUri.length() > 0) {
-                    if (userUri.length() == 0) {
-                        User userWithPassword = userService.getUserByName(user.getName());
-                        userWithPassword.setAuthHash(userService.getHashByUID(userWithPassword.getUid()));
-                        Authentication authentication = new UsernamePasswordAuthenticationToken(
-                                new JuickUser(user), userWithPassword.getCredentials(), JuickUser.USER_AUTHORITY);
-                        SecurityContextHolder.getContext().setAuthentication(authentication);
-                    } else {
-                        // anonymous must have with uri
-                        Authentication authentication = new AnonymousAuthenticationToken(userUri,
-                                new JuickUser(user), JuickUser.ANONYMOUS_AUTHORITY);
-                        SecurityContextHolder.getContext().setAuthentication(authentication);
-                    }
+            var user = signatureManager.verifyActor(request.getMethod(), request.getRequestURI(), headers);
+            String userUri = user.getUri().toString();
+            if (!user.isAnonymous() || userUri.length() > 0) {
+                if (userUri.length() == 0) {
+                    User userWithPassword = userService.getUserByName(user.getName());
+                    userWithPassword.setAuthHash(userService.getHashByUID(userWithPassword.getUid()));
+                    Authentication authentication = new UsernamePasswordAuthenticationToken(
+                            new JuickUser(user), userWithPassword.getCredentials(), JuickUser.USER_AUTHORITY);
+                    SecurityContextHolder.getContext().setAuthentication(authentication);
+                } else {
+                    // anonymous must have with uri
+                    Authentication authentication = new AnonymousAuthenticationToken(userUri,
+                            new JuickUser(user), JuickUser.ANONYMOUS_AUTHORITY);
+                    SecurityContextHolder.getContext().setAuthentication(authentication);
                 }
             }
         }
diff --git a/src/main/java/com/juick/util/ActivityPubRequestInterceptor.java b/src/main/java/com/juick/util/ActivityPubRequestInterceptor.java
index 1876cc90..138a3d09 100644
--- a/src/main/java/com/juick/util/ActivityPubRequestInterceptor.java
+++ b/src/main/java/com/juick/util/ActivityPubRequestInterceptor.java
@@ -30,7 +30,7 @@ public class ActivityPubRequestInterceptor implements ClientHttpRequestIntercept
 
     @Override
     public @NonNull ClientHttpResponse intercept(HttpRequest request, @NonNull byte[] body,
-                                                 ClientHttpRequestExecution execution) throws IOException {
+            ClientHttpRequestExecution execution) throws IOException {
         request.getHeaders().set(HttpHeaders.USER_AGENT, "Juick/2.x");
         return execution.execute(request, body);
     }
diff --git a/src/main/java/com/juick/www/api/Users.java b/src/main/java/com/juick/www/api/Users.java
index f7c24d8d..124632d0 100644
--- a/src/main/java/com/juick/www/api/Users.java
+++ b/src/main/java/com/juick/www/api/Users.java
@@ -72,11 +72,6 @@ public class Users {
     @Inject
     private ApplicationEventPublisher applicationEventPublisher;
 
-    @RequestMapping(value = "/api/auth", method = RequestMethod.GET, produces = MediaType.APPLICATION_JSON_VALUE)
-    public String getAuthToken(@ModelAttribute User visitor) {
-        return userService.getHashByUID(visitor.getUid());
-    }
-
     @RequestMapping(value = "/api/users", method = RequestMethod.GET, produces = MediaType.APPLICATION_JSON_VALUE)
     public List<User> doGetUsers(
             @ModelAttribute User visitor,
@@ -105,7 +100,7 @@ public class Users {
         SecureUser me = new SecureUser();
         me.setUid(visitor.getUid());
         me.setName(visitor.getName());
-        me.setAuthHash(getAuthToken(visitor));
+        me.setAuthHash(userService.getHashByUID(visitor.getUid()));
         List<Integer> unread = messagesService.getUnread(visitor);
         me.setUnread(unread);
         me.setUnreadCount(unread.size());
diff --git a/src/main/java/com/juick/www/controllers/Compat.java b/src/main/java/com/juick/www/controllers/Compat.java
index 936a8e5c..300a0855 100644
--- a/src/main/java/com/juick/www/controllers/Compat.java
+++ b/src/main/java/com/juick/www/controllers/Compat.java
@@ -17,8 +17,11 @@
 
 package com.juick.www.controllers;
 
-import com.juick.SignatureManager;
+import com.juick.service.ActivityPubService;
+import com.juick.service.WebfingerService;
 import com.juick.util.HttpNotFoundException;
+import com.juick.www.api.activity.model.Context;
+import org.springframework.http.MediaType;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.RequestParam;
@@ -30,7 +33,9 @@ import javax.inject.Inject;
 @Controller
 public class Compat {
     @Inject
-    private SignatureManager signatureManager;
+    private WebfingerService webfingerService;
+    @Inject
+    private ActivityPubService activityPubService;
     @GetMapping("/share")
     public RedirectView share(@RequestParam String text, RedirectAttributes attributes) {
         attributes.addAttribute("body", text);
@@ -38,9 +43,10 @@ public class Compat {
     }
     @GetMapping("/mention")
     public RedirectView mention(@RequestParam String username) {
-        var profile = signatureManager.discoverPerson(username);
-        if (profile.isPresent()) {
-            return new RedirectView(profile.get().getUrl());
+        var uri = webfingerService.discoverAccountURI(username, MediaType.valueOf(Context.ACTIVITY_MEDIA_TYPE));
+        if (!uri.toASCIIString().isEmpty()) {
+            var context = activityPubService.get(uri).orElseThrow(HttpNotFoundException::new);
+            return new RedirectView(context.getUrl());
         }
         throw new HttpNotFoundException();
     }
diff --git a/src/main/java/com/mitchellbosecke/pebble/extension/filters/TagsListFilter.java b/src/main/java/com/mitchellbosecke/pebble/extension/filters/TagsListFilter.java
index 14faaa5d..bf4b72fd 100644
--- a/src/main/java/com/mitchellbosecke/pebble/extension/filters/TagsListFilter.java
+++ b/src/main/java/com/mitchellbosecke/pebble/extension/filters/TagsListFilter.java
@@ -25,7 +25,6 @@ import io.pebbletemplates.pebble.template.PebbleTemplate;
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
-import java.util.stream.Collectors;
 
 /**
  * Created by vitalyster on 23.05.2017.