Require non-null proofs in "confirm username hash" requests

service/src/main/java/org/whispersystems/textsecuregcm/entities/ConfirmUsernameHashRequest.java

@@ -7,6 +7,7 @@ package org.whispersystems.textsecuregcm.entities;
 
 import javax.annotation.Nullable;
 import javax.validation.Valid;
+import javax.validation.constraints.NotNull;
 import javax.validation.constraints.Size;
 
 import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
@@ -25,6 +26,7 @@ public record ConfirmUsernameHashRequest(
 
     @JsonSerialize(using = ByteArrayBase64UrlAdapter.Serializing.class)
     @JsonDeserialize(using = ByteArrayBase64UrlAdapter.Deserializing.class)
+    @NotNull
     byte[] zkProof,
 
     @Schema(type = "string", description = "The url-safe base64-encoded encrypted username to be stored for username links")

service/src/test/java/org/whispersystems/textsecuregcm/controllers/AccountControllerTest.java

@@ -13,6 +13,7 @@ import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyByte;
 import static org.mockito.ArgumentMatchers.anyList;
 import static org.mockito.Mockito.clearInvocations;
+import static org.mockito.Mockito.doAnswer;
 import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.eq;
@@ -208,6 +209,17 @@ class AccountControllerTest {
     when(accountsManager.getByE164(eq(SENDER_PREAUTH))).thenReturn(Optional.empty());
     when(accountsManager.getByE164(eq(SENDER_HAS_STORAGE))).thenReturn(Optional.of(senderHasStorage));
     when(accountsManager.getByE164(eq(SENDER_TRANSFER))).thenReturn(Optional.of(senderTransfer));
+
+    doAnswer(invocation -> {
+      final byte[] proof = invocation.getArgument(0);
+      final byte[] hash = invocation.getArgument(1);
+
+      if (proof == null || hash == null) {
+        throw new NullPointerException();
+      }
+
+      return null;
+    }).when(usernameZkProofVerifier).verifyProof(any(), any());
   }
 
   @AfterEach
@@ -595,6 +607,19 @@ class AccountControllerTest {
     verify(usernameZkProofVerifier).verifyProof(ZK_PROOF, USERNAME_HASH_1);
   }
 
+  @Test
+  void testConfirmUsernameHashNullProof() {
+    try (final Response response =
+        resources.getJerseyTest()
+            .target("/v1/accounts/username_hash/confirm")
+            .request()
+            .header(HttpHeaders.AUTHORIZATION, AuthHelper.getAuthHeader(AuthHelper.VALID_UUID, AuthHelper.VALID_PASSWORD))
+            .put(Entity.json(new ConfirmUsernameHashRequest(USERNAME_HASH_1, null, ENCRYPTED_USERNAME_1)))) {
+
+      assertThat(response.getStatus()).isEqualTo(422);
+    }
+  }
+
   @Test
   void testConfirmUsernameHashOld() throws BaseUsernameException {
     Account account = mock(Account.class);