package com.juick.server; import com.fasterxml.jackson.databind.ObjectMapper; import com.juick.User; import com.juick.model.AnonymousUser; import com.juick.server.api.activity.model.Context; import com.juick.server.api.activity.model.objects.Person; import com.juick.server.api.webfinger.model.Account; import com.juick.server.api.webfinger.model.Link; import com.juick.service.UserService; import com.juick.util.DateFormattersHolder; 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.ResponseEntity; import org.springframework.stereotype.Component; import org.springframework.web.client.RestTemplate; import org.springframework.web.util.UriComponentsBuilder; import org.tomitribe.auth.signatures.Signature; import org.tomitribe.auth.signatures.Signer; import org.tomitribe.auth.signatures.Verifier; import rocks.xmpp.addr.Jid; import javax.inject.Inject; import java.io.IOException; import java.net.URI; import java.security.Key; import java.security.NoSuchAlgorithmException; import java.security.SignatureException; import java.time.Instant; import java.util.HashMap; import java.util.Map; import java.util.Optional; import static com.juick.server.api.activity.model.Context.ACTIVITY_MEDIA_TYPE; @Component public class SignatureManager { private static final Logger logger = LoggerFactory.getLogger(ActivityPubManager.class); @Inject private KeystoreManager keystoreManager; @Inject private ObjectMapper jsonMapper; @Inject private UserService userService; @Inject private RestTemplate apClient; public void post(Person from, Person to, Context data) throws IOException { 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(); String signatureString = addSignature(from, host, "POST", inbox.getPath(), requestDate); HttpHeaders requestHeaders = new HttpHeaders(); requestHeaders.add("Content-Type", Context.ACTIVITYSTREAMS_PROFILE_MEDIA_TYPE); requestHeaders.add("Date", requestDate); requestHeaders.add("Host", host); requestHeaders.add("Signature", signatureString); HttpEntity request = new HttpEntity<>(Context.build(data), requestHeaders); logger.info("Sending context: {}", jsonMapper.writeValueAsString(data)); logger.info("Request date: {}", requestDate); ResponseEntity response = apClient.postForEntity(inbox, request, Void.class); logger.info("accepted follower: {}", response.getStatusCodeValue()); } public String addSignature(Person from, String host, String method, String path, String dateString) throws IOException { return addSignature(from, host, method, path, dateString, keystoreManager); } public String addSignature(Person from, String host, String method, String path, String dateString, KeystoreManager keystoreManager) throws IOException { Signature templateSignature = new Signature(from.getPublicKey().getId(), "rsa-sha256", null, "(request-target)", "host", "date"); Map headers = new HashMap<>(); headers.put("host", host); headers.put("date", dateString); 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 headers) { String signatureString = headers.get("signature"); logger.info("Signature: {}", signatureString); Signature signature = Signature.fromString(signatureString); Optional context = getContext(UriComponentsBuilder.fromUriString(signature.getKeyId()) .fragment(null).build().toUri()); if (context.isPresent() && context.get() instanceof Person) { Person person = (Person) context.get(); Key key = KeystoreManager.publicKeyOf(person); Verifier verifier = new Verifier(key, signature); try { boolean result = verifier.verify(method, path, headers); logger.info("signature of {} is valid: {}", signature.getKeyId(), result); if (result) { User user = new User(); user.setUri(URI.create(person.getId())); if (key.equals(keystoreManager.getPublicKey())) { return userService.getUserByName(person.getName()); } return user; } else { return AnonymousUser.INSTANCE; } } catch (NoSuchAlgorithmException | SignatureException | IOException e) { logger.warn("Invalid signature {}", signatureString); } } else { logger.warn("Unknown keyId"); } return AnonymousUser.INSTANCE; } public Optional getContext(URI contextUri) { try { Context context = apClient.getForEntity(contextUri, Context.class).getBody(); if (context == null) { logger.warn("Cannot identify {}", contextUri); return Optional.empty(); } return Optional.of(context); } catch (Exception e) { logger.warn("REST Exception on {}: {}", contextUri, e.getMessage()); } return Optional.empty(); } public Optional discoverPerson(String acct) { Jid acctId = Jid.of(acct); URI resourceUri = UriComponentsBuilder.fromPath("/.well-known/webfinger") .host(acctId.getDomain()) .scheme("https") .queryParam("resource", String.format("%s", acctId.toEscapedString())).build().toUri(); HttpHeaders headers = new HttpHeaders(); headers.add("Accept", "application/jrd+json"); HttpEntity webfingerRequest = new HttpEntity<>(headers); ResponseEntity response = apClient.exchange( resourceUri, HttpMethod.GET, webfingerRequest, Account.class); if (response.getStatusCode().is2xxSuccessful()) { Account acctData = response.getBody(); if (acctData != null) { for (Link l : acctData.getLinks()) { if (l.getRel().equals("self") && l.getType().equals(ACTIVITY_MEDIA_TYPE)) { return getContext(URI.create(l.getHref())); } } } } return Optional.empty(); } }