Added Login5 code (#322)

Author: devgianlu

lib/src/main/java/xyz/gianlu/librespot/core/Login5Api.java

@@ -0,0 +1,156 @@
+/*
+ * Copyright 2021 devgianlu
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package xyz.gianlu.librespot.core;
+
+import com.google.protobuf.ByteString;
+import com.google.protobuf.Duration;
+import com.spotify.login5v3.ClientInfoOuterClass;
+import com.spotify.login5v3.Hashcash;
+import com.spotify.login5v3.Login5;
+import okhttp3.Request;
+import okhttp3.Response;
+import okhttp3.ResponseBody;
+import org.jetbrains.annotations.NotNull;
+import xyz.gianlu.librespot.mercury.MercuryRequests;
+
+import java.io.IOException;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+
+import static xyz.gianlu.librespot.dealer.ApiClient.protoBody;
+
+/**
+ * @author devgianlu
+ */
+public final class Login5Api {
+    private final Session session;
+
+    public Login5Api(@NotNull Session session) {
+        this.session = session;
+    }
+
+    private static boolean checkTenTrailingBits(byte[] array) {
+        if (array[array.length - 1] != 0) return false;
+        else return Integer.numberOfTrailingZeros(array[array.length - 2]) >= 2;
+    }
+
+    private static void incrementCtr(byte[] ctr, int index) {
+        ctr[index]++;
+        if (ctr[index] == 0 && index != 0)
+            incrementCtr(ctr, index - 1);
+    }
+
+    @NotNull
+    private static ChallengeSolve solveHashCash(byte[] prefix, int length, byte[] random) throws NoSuchAlgorithmException {
+        MessageDigest md = MessageDigest.getInstance("SHA1");
+
+        byte[] suffix = new byte[16];
+        System.arraycopy(random, 0, suffix, 0, 8);
+
+        assert length == 10;
+
+        int iters = 0;
+        while (true) {
+            md.reset();
+            md.update(prefix);
+            md.update(suffix);
+            byte[] digest = md.digest();
+            if (checkTenTrailingBits(digest))
+                return new ChallengeSolve(suffix, iters);
+
+            incrementCtr(suffix, suffix.length - 1);
+            incrementCtr(suffix, 7);
+            iters++;
+        }
+    }
+
+    @NotNull
+    private static Login5.LoginRequest.Builder solveChallenge(@NotNull Login5.LoginResponse resp) throws NoSuchAlgorithmException {
+        byte[] loginContext = resp.getLoginContext().toByteArray();
+
+        Hashcash.HashcashChallenge hashcash = resp.getChallenges().getChallenges(0).getHashcash();
+
+        byte[] prefix = hashcash.getPrefix().toByteArray();
+        byte[] seed = new byte[8];
+        byte[] loginContextDigest = MessageDigest.getInstance("SHA1").digest(loginContext);
+        System.arraycopy(loginContextDigest, 12, seed, 0, 8);
+
+        long start = System.nanoTime();
+        ChallengeSolve solved = solveHashCash(prefix, hashcash.getLength(), seed);
+        long durationNano = System.nanoTime() - start;
+
+        return Login5.LoginRequest.newBuilder()
+                .setLoginContext(ByteString.copyFrom(loginContext))
+                .setChallengeSolutions(Login5.ChallengeSolutions.newBuilder()
+                        .addSolutions(Login5.ChallengeSolution.newBuilder()
+                                .setHashcash(Hashcash.HashcashSolution.newBuilder()
+                                        .setDuration(Duration.newBuilder()
+                                                .setSeconds((int) (durationNano / 1_000_000_000))
+                                                .setNanos((int) (durationNano % 1_000_000_000))
+                                                .build())
+                                        .setSuffix(ByteString.copyFrom(solved.suffix))
+                                        .build()).build()).build());
+    }
+
+    @NotNull
+    private Login5.LoginResponse send(@NotNull Login5.LoginRequest msg) throws IOException {
+        Request.Builder req = new Request.Builder()
+                .method("POST", protoBody(msg))
+                .url("https://login5.spotify.com/v3/login");
+
+        try (Response resp = session.client().newCall(req.build()).execute()) {
+            ResponseBody body = resp.body();
+            if (body == null) throw new IOException("No body");
+            return Login5.LoginResponse.parseFrom(body.bytes());
+        }
+    }
+
+    @NotNull
+    public Login5.LoginResponse login5(@NotNull Login5.LoginRequest req) throws IOException, NoSuchAlgorithmException {
+        req = req.toBuilder()
+                .setClientInfo(ClientInfoOuterClass.ClientInfo.newBuilder()
+                        .setClientId(MercuryRequests.KEYMASTER_CLIENT_ID)
+                        .setDeviceId(session.deviceId())
+                        .build())
+                .build();
+
+        Login5.LoginResponse resp = send(req);
+        if (resp.hasChallenges()) {
+            Login5.LoginRequest.Builder reqq = solveChallenge(resp);
+            reqq.setClientInfo(req.getClientInfo())
+                    .setAppleSignInCredential(req.getAppleSignInCredential())
+                    .setFacebookAccessToken(req.getFacebookAccessToken())
+                    .setOneTimeToken(req.getOneTimeToken())
+                    .setPhoneNumber(req.getPhoneNumber())
+                    .setStoredCredential(req.getStoredCredential())
+                    .setPassword(req.getPassword());
+            resp = send(reqq.build());
+        }
+
+        return resp;
+    }
+
+    private static class ChallengeSolve {
+        final byte[] suffix;
+        final int ctr;
+
+        ChallengeSolve(byte[] suffix, int ctr) {
+            this.suffix = suffix;
+            this.ctr = ctr;
+        }
+    }
+}

lib/src/main/java/xyz/gianlu/librespot/dealer/ApiClient.java

@@ -37,9 +37,9 @@
 import static com.spotify.canvaz.CanvazOuterClass.EntityCanvazResponse;
 
 /**
- * @author Gianlu
+ * @author devgianlu
  */
-public class ApiClient {
+public final class ApiClient {
     private static final Logger LOGGER = LoggerFactory.getLogger(ApiClient.class);
     private final Session session;
     private final String baseUrl;
@@ -50,7 +50,7 @@ public ApiClient(@NotNull Session session) {
     }
 
     @NotNull
-    private static RequestBody protoBody(@NotNull Message msg) {
+    public static RequestBody protoBody(@NotNull Message msg) {
         return new RequestBody() {
             @Override
             public MediaType contentType() {

lib/src/main/java/xyz/gianlu/librespot/mercury/MercuryRequests.java

@@ -35,7 +35,7 @@
  * @author Gianlu
  */
 public final class MercuryRequests {
-    private static final String KEYMASTER_CLIENT_ID = "65b708073fc0480ea92a077233ca87bd";
+    public static final String KEYMASTER_CLIENT_ID = "65b708073fc0480ea92a077233ca87bd";
 
     private MercuryRequests() {
     }