Made public/private keys actually work

src/main/java/lt/pow/nukagit/db/repositories/PublicKeyRepository.java

@@ -6,8 +6,6 @@
 import lt.pow.nukagit.db.entities.UserPublicKey;
 
 import javax.inject.Inject;
-import java.security.SecureRandom;
-import java.util.Collection;
 import java.util.List;
 import java.util.concurrent.TimeUnit;
 import java.util.function.Supplier;
@@ -48,7 +46,7 @@ public void addUserWithKey(String username, String publicKey) throws InvalidKeyS
         publicKeysDao.addPublicKey(userId, publicKeyData.fingerprint(), publicKeyData);
     }
 
-    public Collection<UserPublicKey> getPublicKeyCollection() {
-        return publicKeyCache.get();
+    public Supplier<List<UserPublicKey>> getPublicKeySupplier() {
+        return publicKeyCache;
     }
 }

src/main/java/lt/pow/nukagit/ssh/SshModule.java

@@ -4,11 +4,11 @@
 import dagger.Module;
 import dagger.Provides;
 import dagger.multibindings.IntoSet;
+import lt.pow.nukagit.db.repositories.PublicKeyRepository;
 import lt.pow.nukagit.dfs.DfsRepositoryResolver;
 import lt.pow.nukagit.dfs.GitDfsPackCommandFactory;
 import lt.pow.nukagit.lib.lifecycle.Managed;
 import org.apache.sshd.server.SshServer;
-import org.apache.sshd.server.auth.pubkey.AcceptAllPublickeyAuthenticator;
 import org.apache.sshd.server.keyprovider.SimpleGeneratorHostKeyProvider;
 import org.github.gestalt.config.Gestalt;
 import org.github.gestalt.config.exceptions.GestaltException;
@@ -35,18 +35,18 @@ static SshServerConfig configuration(Gestalt configurationProvider) {
   @Provides
   @Singleton
   static SshServer createServer(
-      DfsRepositoryResolver dfsRepositoryResolver, SshServerConfig sshServerConfig) {
+          DfsRepositoryResolver dfsRepositoryResolver,
+          SshServerConfig sshServerConfig,
+          PublicKeyRepository publicKeyRepository) {
     var sshServer = SshServer.setUpDefaultServer();
     sshServer.setHost(sshServerConfig.hostname());
     sshServer.setPort(sshServerConfig.port());
     var keyPairGenerator = new SimpleGeneratorHostKeyProvider(Path.of(sshServerConfig.hostKey()));
     keyPairGenerator.setAlgorithm(sshServerConfig.hostKeyAlgorithm());
     sshServer.setKeyPairProvider(keyPairGenerator);
-    // sshServer.setPublickeyAuthenticator(new CachingPublicKeyAuthenticator(new KeySetPublickeyAuthenticator(
-    //        "PublicKeyAuthenticator",
-    //        ImmutableList.of()
-    // )));
-    sshServer.setPublickeyAuthenticator(AcceptAllPublickeyAuthenticator.INSTANCE);
+    sshServer.setPublickeyAuthenticator(new UsernameResolvingPublickeyAuthenticator(
+          publicKeyRepository.getPublicKeySupplier()
+    ));
     sshServer.setCommandFactory(
         new GitDfsPackCommandFactory().withDfsRepositoryResolver(dfsRepositoryResolver));
     return sshServer;

src/main/java/lt/pow/nukagit/ssh/UsernameResolvingPublickeyAuthenticator.java

@@ -0,0 +1,42 @@
+package lt.pow.nukagit.ssh;
+
+import lt.pow.nukagit.db.entities.UserPublicKey;
+import org.apache.sshd.common.config.keys.KeyUtils;
+import org.apache.sshd.server.auth.AsyncAuthException;
+import org.apache.sshd.server.auth.pubkey.PublickeyAuthenticator;
+import org.apache.sshd.server.session.ServerSession;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.security.PublicKey;
+import java.util.List;
+import java.util.function.Supplier;
+
+public class UsernameResolvingPublickeyAuthenticator implements PublickeyAuthenticator {
+
+    Logger LOGGER = LoggerFactory.getLogger(UsernameResolvingPublickeyAuthenticator.class);
+    private final Supplier<List<UserPublicKey>> keySetSupplier;
+
+    public UsernameResolvingPublickeyAuthenticator(Supplier<List<UserPublicKey>> keySetSupplier) {
+        this.keySetSupplier = keySetSupplier;
+    }
+
+    @Override
+    public boolean authenticate(String username, PublicKey key, ServerSession session) throws AsyncAuthException {
+        if (!username.equals("git")) {
+            LOGGER.warn("User {} tried to authenticate with public key, but all users should" +
+                    " use git as their username", username);
+            return false;
+        }
+        var allKeys = keySetSupplier.get();
+        LOGGER.info("Trying to authenticate user {} with public key against {} keys", username, allKeys.size());
+        for (var userPublicKey : allKeys) {
+            if (KeyUtils.compareKeys(userPublicKey.publicKeyData().key(), key)) {
+                session.setUsername(userPublicKey.username());
+                LOGGER.info("User {} authenticated with public key", userPublicKey.username());
+                return true;
+            }
+        }
+        return false;
+    }
+}

src/test/groovy/lt/pow/nukagit/db/repositories/PublicKeyRepositoryDaoTest.groovy

@@ -37,8 +37,9 @@ class PublicKeyRepositoryDaoTest extends DatabaseTestBase {
         when:
         repository.addUserWithKey(username, publicKey)
         then:
-        repository.publicKeyCollection.size() == 1
-        def userKey = repository.publicKeyCollection[0]
+        def keyList = repository.publicKeySupplier.get()
+        keyList.size() == 1
+        def userKey = keyList[0]
         userKey.username() == username
         userKey.publicKeyData() == testKeyData
     }