From c09ae9a234d462387502ae26635fb21311804b4e Mon Sep 17 00:00:00 2001
From: Greyson Parrelli <greyson@signal.org>
Date: Mon, 24 Jul 2023 17:48:34 -0400
Subject: [PATCH] Ensure we use SVR2 endpoint for checking RRP.

---
 .../internal/push/BackupAuthCheckRequest.kt   |  4 ++
 .../internal/push/PushServiceSocket.java      | 41 +++++++++++++++----
 2 files changed, 37 insertions(+), 8 deletions(-)

diff --git a/libsignal/service/src/main/java/org/whispersystems/signalservice/internal/push/BackupAuthCheckRequest.kt b/libsignal/service/src/main/java/org/whispersystems/signalservice/internal/push/BackupAuthCheckRequest.kt
index 1128b674fd..31243bea1a 100644
--- a/libsignal/service/src/main/java/org/whispersystems/signalservice/internal/push/BackupAuthCheckRequest.kt
+++ b/libsignal/service/src/main/java/org/whispersystems/signalservice/internal/push/BackupAuthCheckRequest.kt
@@ -30,6 +30,10 @@ data class BackupAuthCheckResponse @JsonCreator constructor(
   private fun String.toBasic(): String {
     return "Basic ${encode(StandardCharsets.ISO_8859_1).base64()}"
   }
+
+  fun merge(other: BackupAuthCheckResponse): BackupAuthCheckResponse {
+    return BackupAuthCheckResponse(this.matches + other.matches)
+  }
 }
 
 /**
diff --git a/libsignal/service/src/main/java/org/whispersystems/signalservice/internal/push/PushServiceSocket.java b/libsignal/service/src/main/java/org/whispersystems/signalservice/internal/push/PushServiceSocket.java
index 2db6444737..28f16acbb1 100644
--- a/libsignal/service/src/main/java/org/whispersystems/signalservice/internal/push/PushServiceSocket.java
+++ b/libsignal/service/src/main/java/org/whispersystems/signalservice/internal/push/PushServiceSocket.java
@@ -297,7 +297,8 @@ public class PushServiceSocket {
 
   private static final String REPORT_SPAM = "/v1/messages/report/%s/%s";
 
-  private static final String BACKUP_AUTH_CHECK = "/v1/backup/auth/check";
+  private static final String BACKUP_AUTH_CHECK_V1 = "/v1/backup/auth/check";
+  private static final String BACKUP_AUTH_CHECK_V2 = "/v2/backup/auth/check";
 
   private static final String CALL_LINK_CREATION_AUTH = "/v1/call-link/create-auth";
   private static final String SERVER_DELIVERED_TIMESTAMP_HEADER = "X-Signal-Timestamp";
@@ -973,17 +974,41 @@ public class PushServiceSocket {
   public Single<ServiceResponse<BackupAuthCheckResponse>> checkBackupAuthCredentials(@Nonnull BackupAuthCheckRequest request,
                                                                                      @Nonnull ResponseMapper<BackupAuthCheckResponse> responseMapper)
   {
-    Single<ServiceResponse<BackupAuthCheckResponse>> requestSingle = Single.fromCallable(() -> {
-      try (Response response = getServiceConnection(BACKUP_AUTH_CHECK, "POST", jsonRequestBody(JsonUtil.toJson(request)), Collections.emptyMap(), Optional.empty(), false)) {
+    return Single
+        .zip(
+          createBackupAuthCheckSingle(BACKUP_AUTH_CHECK_V1, request, responseMapper),
+          createBackupAuthCheckSingle(BACKUP_AUTH_CHECK_V2, request, responseMapper),
+          (v1, v2) -> {
+            if (v1.getResult().isPresent() && v2.getResult().isPresent()) {
+              BackupAuthCheckResponse v1Result = v1.getResult().get();
+              BackupAuthCheckResponse v2Result = v2.getResult().get();
+              BackupAuthCheckResponse merged   = v1Result.merge(v2Result);
+
+              return new ServiceResponse<>(v2.getStatus(), null, merged, null, null);
+            } else if (v1.getResult().isEmpty() && v2.getResult().isEmpty()) {
+              return v2;
+            } else if (v2.getResult().isEmpty()) {
+              return v1;
+            } else {
+              return v2;
+            }
+          }
+        )
+        .subscribeOn(Schedulers.io())
+        .observeOn(Schedulers.io())
+        .onErrorReturn(ServiceResponse::forUnknownError);
+  }
+
+  private Single<ServiceResponse<BackupAuthCheckResponse>> createBackupAuthCheckSingle(@Nonnull String path,
+                                                                                       @Nonnull BackupAuthCheckRequest request,
+                                                                                       @Nonnull ResponseMapper<BackupAuthCheckResponse> responseMapper)
+  {
+    return Single.fromCallable(() -> {
+      try (Response response = getServiceConnection(path, "POST", jsonRequestBody(JsonUtil.toJson(request)), Collections.emptyMap(), Optional.empty(), false)) {
         String body = response.body() != null ? readBodyString(response.body()): "";
         return responseMapper.map(response.code(), body, response::header, false);
       }
     });
-
-    return requestSingle
-        .subscribeOn(Schedulers.io())
-        .observeOn(Schedulers.io())
-        .onErrorReturn(ServiceResponse::forUnknownError);
   }
 
   /**