fix: return unsupported for email and kdf flows

src/handlers/sends-private.ts

@@ -35,6 +35,8 @@ import {
 } from './sends-shared';
 import { auditRequestMetadata, writeAuditEvent } from '../services/audit-events';
 
+const SEND_EMAIL_AUTH_UNSUPPORTED_MESSAGE = 'Send email verification is not supported by this server.';
+
 async function writeSendAudit(
   storage: StorageService,
   request: Request,
@@ -216,11 +218,17 @@ export async function handleCreateSend(request: Request, env: Env, userId: strin
   if (authTypeRaw.present && requestedAuthType === null) {
     return errorResponse('Invalid authType', 400);
   }
+  if (requestedAuthType === SendAuthType.Email) {
+    return errorResponse(SEND_EMAIL_AUTH_UNSUPPORTED_MESSAGE, 501);
+  }
 
   const normalizedEmails = normalizeEmails(emailsRaw.value);
   if (emailsRaw.present && emailsRaw.value !== null && normalizedEmails === null) {
     return errorResponse('Invalid emails', 400);
   }
+  if (normalizedEmails) {
+    return errorResponse(SEND_EMAIL_AUTH_UNSUPPORTED_MESSAGE, 501);
+  }
 
   const now = new Date().toISOString();
   const send: Send = {
@@ -340,11 +348,17 @@ export async function handleCreateFileSendV2(request: Request, env: Env, userId:
   if (authTypeRaw.present && requestedAuthType === null) {
     return errorResponse('Invalid authType', 400);
   }
+  if (requestedAuthType === SendAuthType.Email) {
+    return errorResponse(SEND_EMAIL_AUTH_UNSUPPORTED_MESSAGE, 501);
+  }
 
   const normalizedEmails = normalizeEmails(emailsRaw.value);
   if (emailsRaw.present && emailsRaw.value !== null && normalizedEmails === null) {
     return errorResponse('Invalid emails', 400);
   }
+  if (normalizedEmails) {
+    return errorResponse(SEND_EMAIL_AUTH_UNSUPPORTED_MESSAGE, 501);
+  }
 
   const now = new Date().toISOString();
   const send: Send = {
@@ -598,10 +612,11 @@ export async function handleUpdateSend(request: Request, env: Env, userId: strin
     if (parsedAuthType === null) {
       return errorResponse('Invalid authType', 400);
     }
-    send.authType = parsedAuthType;
-    if (parsedAuthType !== SendAuthType.Email) {
-      send.emails = null;
+    if (parsedAuthType === SendAuthType.Email) {
+      return errorResponse(SEND_EMAIL_AUTH_UNSUPPORTED_MESSAGE, 501);
     }
+    send.authType = parsedAuthType;
+    send.emails = null;
   }
 
   const emailsRaw = getAliasedProp(body, ['emails', 'Emails']);
@@ -610,10 +625,13 @@ export async function handleUpdateSend(request: Request, env: Env, userId: strin
     if (emailsRaw.value !== null && normalizedEmails === null) {
       return errorResponse('Invalid emails', 400);
     }
+    if (normalizedEmails) {
+      return errorResponse(SEND_EMAIL_AUTH_UNSUPPORTED_MESSAGE, 501);
+    }
     send.emails = normalizedEmails;
     if (send.emails) {
       send.authType = SendAuthType.Email;
-    } else if (send.authType === SendAuthType.Email) {
+    } else if (Number(send.authType) === SendAuthType.Email) {
       send.authType = SendAuthType.None;
     }
   }

src/handlers/sends-public.ts

@@ -368,7 +368,7 @@ export async function issueSendAccessToken(
             Object: 'error',
           },
         },
-        400
+        501
       ),
     };
   }

src/handlers/sends-shared.ts

@@ -464,7 +464,11 @@ export function sendPasswordLockedOAuthResponse(retryAfterSeconds: number): Resp
 
 export async function validatePublicSendAccess(send: Send, body: unknown): Promise<PublicSendAccessValidationResult> {
   if (hasEmailAuth(send)) {
-    return { ok: false, response: errorResponse(SEND_INACCESSIBLE_MSG, 404), reason: 'email_auth_unsupported' };
+    return {
+      ok: false,
+      response: errorResponse('Send email verification is not supported by this server.', 501),
+      reason: 'email_auth_unsupported',
+    };
   }
 
   if (!send.passwordHash) return { ok: true };