zkgroup/codegen/codegen_hack.patch

diff --git b/ffi/java/src/main/java/org/signal/zkgroup/auth/ServerZkAuthOperations.java a/ffi/java/src/main/java/org/signal/zkgroup/auth/ServerZkAuthOperations.java
index a2567a55ef32..57d99c13ed71 100644
--- b/ffi/java/src/main/java/org/signal/zkgroup/auth/ServerZkAuthOperations.java
+++ a/ffi/java/src/main/java/org/signal/zkgroup/auth/ServerZkAuthOperations.java
@@ -11,9 +11,11 @@ package org.signal.zkgroup.auth;
 
 import java.security.SecureRandom;
 import java.util.UUID;
+import java.util.concurrent.TimeUnit;
 import org.signal.zkgroup.InvalidInputException;
 import org.signal.zkgroup.ServerSecretParams;
 import org.signal.zkgroup.VerificationFailedException;
+import org.signal.zkgroup.InvalidRedemptionTimeException;
 import org.signal.zkgroup.ZkGroupError;
 import org.signal.zkgroup.groups.GroupPublicParams;
 import org.signal.zkgroup.internal.Native;
@@ -51,7 +53,18 @@ public class ServerZkAuthOperations {
 
   }
 
-  public void verifyAuthCredentialPresentation(GroupPublicParams groupPublicParams, AuthCredentialPresentation authCredentialPresentation) throws VerificationFailedException {
+  public void verifyAuthCredentialPresentation(GroupPublicParams groupPublicParams, AuthCredentialPresentation authCredentialPresentation) throws VerificationFailedException, InvalidRedemptionTimeException {
+       verifyAuthCredentialPresentation(groupPublicParams, authCredentialPresentation, System.currentTimeMillis());
+     }
+
+  public void verifyAuthCredentialPresentation(GroupPublicParams groupPublicParams, AuthCredentialPresentation authCredentialPresentation, long currentTimeMillis) throws VerificationFailedException, InvalidRedemptionTimeException {
+    long acceptableStartTime = TimeUnit.MILLISECONDS.convert(authCredentialPresentation.getRedemptionTime()-1, TimeUnit.DAYS);
+    long acceptableEndTime = TimeUnit.MILLISECONDS.convert(authCredentialPresentation.getRedemptionTime()+2, TimeUnit.DAYS);
+
+    if (currentTimeMillis < acceptableStartTime || currentTimeMillis > acceptableEndTime) {
+        throw new InvalidRedemptionTimeException();
+    }
+
     int ffi_return = Native.serverSecretParamsVerifyAuthCredentialPresentationJNI(serverSecretParams.getInternalContentsForJNI(), groupPublicParams.getInternalContentsForJNI(), authCredentialPresentation.getInternalContentsForJNI());
     if (ffi_return == Native.FFI_RETURN_INPUT_ERROR) {
       throw new VerificationFailedException();
diff --git b/ffi/java/src/main/java/org/signal/zkgroup/groups/ClientZkGroupCipher.java a/ffi/java/src/main/java/org/signal/zkgroup/groups/ClientZkGroupCipher.java
index 464cf6d19ecc..5739505935b0 100644
--- b/ffi/java/src/main/java/org/signal/zkgroup/groups/ClientZkGroupCipher.java
+++ a/ffi/java/src/main/java/org/signal/zkgroup/groups/ClientZkGroupCipher.java
@@ -9,6 +9,7 @@
 
 package org.signal.zkgroup.groups;
 
+import java.nio.ByteBuffer;
 import java.security.SecureRandom;
 import java.util.UUID;
 import org.signal.zkgroup.InvalidInputException;
@@ -100,12 +101,16 @@ public class ClientZkGroupCipher {
   }
 
   public byte[] encryptBlob(SecureRandom secureRandom, byte[] plaintext) throws VerificationFailedException {
-    byte[] newContents = new byte[plaintext.length + 29];
+
+    byte[] paddedPlaintext = new byte[plaintext.length + 4];
+    System.arraycopy(plaintext, 0, paddedPlaintext, 4, plaintext.length);
+
+    byte[] newContents = new byte[paddedPlaintext.length + 29];
     byte[] random      = new byte[Native.RANDOM_LENGTH];
 
     secureRandom.nextBytes(random);
 
-    int ffi_return = Native.groupSecretParamsEncryptBlobDeterministicJNI(groupSecretParams.getInternalContentsForJNI(), random, plaintext, newContents);
+    int ffi_return = Native.groupSecretParamsEncryptBlobDeterministicJNI(groupSecretParams.getInternalContentsForJNI(), random, paddedPlaintext, newContents);
     if (ffi_return == Native.FFI_RETURN_INPUT_ERROR) {
       throw new VerificationFailedException();
     }
@@ -129,7 +134,21 @@ public class ClientZkGroupCipher {
       throw new ZkGroupError("FFI_RETURN!=OK");
     }
 
-    return newContents;
+    if (newContents.length < 4) {
+        throw new VerificationFailedException();
+    }
+
+    byte[] padLenBytes = new byte[4];
+    System.arraycopy(newContents, 0, padLenBytes, 0, 4);
+    int padLen = ByteBuffer.wrap(newContents).getInt();
+    if (newContents.length < (4 + padLen))  {
+        throw new VerificationFailedException();
+    }
+
+    byte[] depaddedContents = new byte[newContents.length - (4 + padLen)];
+    System.arraycopy(newContents, 4, depaddedContents, 0, newContents.length - (4 + padLen));
+
+    return depaddedContents;
   }
 
 }
diff --git b/ffi/java/src/main/java/org/signal/zkgroup/profiles/ClientZkProfileOperations.java a/ffi/java/src/main/java/org/signal/zkgroup/profiles/ClientZkProfileOperations.java
index cbc73ac60bee..57a252f5886d 100644
--- b/ffi/java/src/main/java/org/signal/zkgroup/profiles/ClientZkProfileOperations.java
+++ a/ffi/java/src/main/java/org/signal/zkgroup/profiles/ClientZkProfileOperations.java
@@ -52,6 +52,10 @@ public class ClientZkProfileOperations {
   }
 
   public ProfileKeyCredential receiveProfileKeyCredential(ProfileKeyCredentialRequestContext profileKeyCredentialRequestContext, ProfileKeyCredentialResponse profileKeyCredentialResponse) throws VerificationFailedException {
+    if (profileKeyCredentialResponse == null) {
+      throw new VerificationFailedException();
+    }
+
     byte[] newContents = new byte[ProfileKeyCredential.SIZE];
 
     int ffi_return = Native.serverPublicParamsReceiveProfileKeyCredentialJNI(serverPublicParams.getInternalContentsForJNI(), profileKeyCredentialRequestContext.getInternalContentsForJNI(), profileKeyCredentialResponse.getInternalContentsForJNI(), newContents);
diff --git b/ffi/java/src/main/java/org/signal/zkgroup/profiles/ProfileKey.java a/ffi/java/src/main/java/org/signal/zkgroup/profiles/ProfileKey.java
index 2251da362b0e..9170b5fd9a5c 100644
--- b/ffi/java/src/main/java/org/signal/zkgroup/profiles/ProfileKey.java
+++ a/ffi/java/src/main/java/org/signal/zkgroup/profiles/ProfileKey.java
@@ -25,14 +25,10 @@ public final class ProfileKey extends ByteArray {
     super(contents, SIZE);
   }
 
-  public ProfileKeyCommitment getCommitment(UUID uuid) throws VerificationFailedException {
+  public ProfileKeyCommitment getCommitment(UUID uuid) {
     byte[] newContents = new byte[ProfileKeyCommitment.SIZE];
 
     int ffi_return = Native.profileKeyGetCommitmentJNI(contents, UUIDUtil.serialize(uuid), newContents);
-    if (ffi_return == Native.FFI_RETURN_INPUT_ERROR) {
-      throw new VerificationFailedException();
-    }
-
     if (ffi_return != Native.FFI_RETURN_OK) {
       throw new ZkGroupError("FFI_RETURN!=OK");
     }
@@ -45,14 +41,10 @@ public final class ProfileKey extends ByteArray {
 
   }
 
-  public ProfileKeyVersion getProfileKeyVersion(UUID uuid) throws VerificationFailedException {
+  public ProfileKeyVersion getProfileKeyVersion(UUID uuid) {
     byte[] newContents = new byte[ProfileKeyVersion.SIZE];
 
     int ffi_return = Native.profileKeyGetProfileKeyVersionJNI(contents, UUIDUtil.serialize(uuid), newContents);
-    if (ffi_return == Native.FFI_RETURN_INPUT_ERROR) {
-      throw new VerificationFailedException();
-    }
-
     if (ffi_return != Native.FFI_RETURN_OK) {
       throw new ZkGroupError("FFI_RETURN!=OK");
     }
diff --git b/ffi/swift/Sources/ZKGroup/ClientZkGroupCipher.swift a/ffi/swift/Sources/ZKGroup/ClientZkGroupCipher.swift
index 4d36edb46acf..fa7f1b4aba5c 100644
--- b/ffi/swift/Sources/ZKGroup/ClientZkGroupCipher.swift
+++ a/ffi/swift/Sources/ZKGroup/ClientZkGroupCipher.swift
@@ -91,7 +91,7 @@ public class ClientZkGroupCipher {
 
   }
 
-  public func encryptBlob(plaintext: [UInt8]) throws  -> BlobCiphertext {
+  public func encryptBlob(plaintext: [UInt8]) throws  -> [UInt8] {
     var randomness: [UInt8] = Array(repeating: 0, count: Int(32))
     let result = SecRandomCopyBytes(kSecRandomDefault, randomness.count, &randomness)
     guard result == errSecSuccess else {
@@ -102,9 +102,11 @@ public class ClientZkGroupCipher {
   }
 
   public func encryptBlob(randomness: [UInt8], plaintext: [UInt8]) throws  -> [UInt8] {
-    var newContents: [UInt8] = Array(repeating: 0, count: Int(plaintext.count + 29))
+    let paddedPlaintext = Array(repeating:0, count: 4) + plaintext
 
-    let ffi_return = FFI_GroupSecretParams_encryptBlobDeterministic(groupSecretParams.getInternalContentsForFFI(), UInt32(groupSecretParams.getInternalContentsForFFI().count), randomness, UInt32(randomness.count), plaintext, UInt32(plaintext.count), &newContents, UInt32(newContents.count))
+    var newContents: [UInt8] = Array(repeating: 0, count: Int(paddedPlaintext.count + 29))
+
+    let ffi_return = FFI_GroupSecretParams_encryptBlobDeterministic(groupSecretParams.getInternalContentsForFFI(), UInt32(groupSecretParams.getInternalContentsForFFI().count), randomness, UInt32(randomness.count), paddedPlaintext, UInt32(paddedPlaintext.count), &newContents, UInt32(newContents.count))
     if (ffi_return == Native.FFI_RETURN_INPUT_ERROR) {
       throw ZkGroupException.VerificationFailed
     }
@@ -128,7 +131,18 @@ public class ClientZkGroupCipher {
       throw ZkGroupException.ZkGroupError
     }
 
-    return newContents
+    if newContents.count < 4 {
+        throw ZkGroupException.VerificationFailed
+    }
+
+    var paddingLen = newContents.withUnsafeBytes({ $0.load(fromByteOffset:0, as: UInt32.self) })
+    paddingLen = UInt32(bigEndian: paddingLen)
+
+    if (newContents.count < (4 + paddingLen))  {
+        throw ZkGroupException.VerificationFailed
+    }
+
+    return Array(newContents[4 ..< newContents.endIndex - Int(paddingLen)])
   }
 
 }