From 228cd533d239e02ad2e30321656d8b12ef28b6fb Mon Sep 17 00:00:00 2001
From: Galindo97 <agalindo@aduanasoft.com.mx>
Date: Thu, 14 May 2026 08:30:15 -0500
Subject: [PATCH] fix(sso): reduce cookie chunk threshold and add defensive
 error handling in SSO exchange
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- Reduce ACCESS_TOKEN_MAX_SINGLE y ACCESS_TOKEN_CHUNK_SIZE de 3500 a 2800
  para garantizar que cada cookie fragmentada no supere el límite de 4096 bytes
  del navegador (incluye overhead del nombre, path, attrs).
- Agrega try/catch alrededor de response.json() en el load de /auth/sso para
  evitar SyntaxError no manejado si el body no es JSON.
- Type guards explícitos en tokens.access_token, refresh_token y tenant_id
  para detectar respuestas incompletas del hub antes de llamar cookies.set().
- .catch(() => ({})) en refreshRes.json() para que el refresh proactivo nunca
  bloquee el flujo SSO aunque el body sea inesperado.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
---
 .../src/lib/access-token-cookie.shared.ts     |  4 +--
 frontend/src/routes/auth/sso/+page.server.ts  | 28 +++++++++++++------
 2 files changed, 22 insertions(+), 10 deletions(-)

diff --git a/frontend/src/lib/access-token-cookie.shared.ts b/frontend/src/lib/access-token-cookie.shared.ts
index 182c073f..84766451 100644
--- a/frontend/src/lib/access-token-cookie.shared.ts
+++ b/frontend/src/lib/access-token-cookie.shared.ts
@@ -4,9 +4,9 @@
  */
 
 /** Por debajo de esto se usa una sola cookie `access_token` (compatibilidad). */
-export const ACCESS_TOKEN_MAX_SINGLE = 3500;
+export const ACCESS_TOKEN_MAX_SINGLE = 2800;
 
-export const ACCESS_TOKEN_CHUNK_SIZE = 3500;
+export const ACCESS_TOKEN_CHUNK_SIZE = 2800;
 
 /** Número de fragmentos; si existe, el token está en access_token_0..access_token_{n-1}. */
 export const ACCESS_TOKEN_CHUNK_COUNT = 'access_token_chunks';
diff --git a/frontend/src/routes/auth/sso/+page.server.ts b/frontend/src/routes/auth/sso/+page.server.ts
index 1a87a7d6..df2560a8 100644
--- a/frontend/src/routes/auth/sso/+page.server.ts
+++ b/frontend/src/routes/auth/sso/+page.server.ts
@@ -76,10 +76,22 @@ export const load: PageServerLoad = async ({ url, cookies }) => {
 		redirectToWorkspaceLogin(cookies, url);
 	}
 
-	let tokens = await response.json();
+	let tokens: Record<string, unknown>;
+	try {
+		tokens = await response.json();
+	} catch (err) {
+		console.error('[SSO] exchange devolvió body no-JSON (status 200):', err);
+		redirectToWorkspaceLogin(cookies, url);
+	}
+
+	if (!tokens.access_token || typeof tokens.access_token !== 'string') {
+		console.error('[SSO] exchange exitoso pero access_token faltante o inválido:', tokens);
+		redirectToWorkspaceLogin(cookies, url);
+	}
+
 	console.log('[SSO] exchange exitoso, tokens recibidos:', {
 		hasAccessToken: !!tokens.access_token,
-		accessTokenLen: tokens.access_token?.length,
+		accessTokenLen: (tokens.access_token as string).length,
 		hasRefreshToken: !!tokens.refresh_token,
 		tenant_id: tokens.tenant_id,
 		tenant_slug: tokens.tenant_slug,
@@ -89,7 +101,7 @@ export const load: PageServerLoad = async ({ url, cookies }) => {
 	// Los tokens del relay fueron emitidos por KC via el browser (iss=IP:8085).
 	// El Hub backend valida contra KC interno (hub-keycloak:8080) → issuer mismatch → 401.
 	// Refrescando aquí: Anexo76 backend → Hub → KC interno → iss=hub-keycloak:8080 → válido.
-	if (tokens.refresh_token) {
+	if (typeof tokens.refresh_token === 'string') {
 		try {
 			const internalApiUrl = (
 				process.env.INTERNAL_API_URL ||
@@ -102,7 +114,7 @@ export const load: PageServerLoad = async ({ url, cookies }) => {
 				body: JSON.stringify({ refresh_token: tokens.refresh_token }),
 			});
 			if (refreshRes.ok) {
-				const refreshed = await refreshRes.json();
+				const refreshed = await refreshRes.json().catch(() => ({}));
 				if (refreshed.access_token && refreshed.refresh_token) {
 					tokens = { ...tokens, ...refreshed };
 					console.log('[SSO] tokens refrescados exitosamente (iss normalizado)');
@@ -120,13 +132,13 @@ export const load: PageServerLoad = async ({ url, cookies }) => {
 	console.log('[SSO] ORIGIN-based secure context:', isProduction);
 
 	// access_token — NO HttpOnly (Bearer desde JS); fragmentado si el JWT supera ~4KB
-	setAccessTokenCookies(cookies, tokens.access_token, {
+	setAccessTokenCookies(cookies, tokens.access_token as string, {
 		secure: isProduction,
 		maxAge: 60 * 60 * 24 * 7,
 	});
 
 	// refresh_token — HttpOnly (never exposed to JS)
-	if (tokens.refresh_token) {
+	if (typeof tokens.refresh_token === 'string') {
 		cookies.set('refresh_token', tokens.refresh_token, {
 			path: '/',
 			httpOnly: true,
@@ -139,7 +151,7 @@ export const load: PageServerLoad = async ({ url, cookies }) => {
 	// sso_tenant_id — HttpOnly cookie con el tenant seleccionado.
 	// El backend lo pasa como X-Tenant-Override en Hub /auth/me para que
 	// devuelva el tenant correcto aunque el KC token tenga otro tenant baked in.
-	if (tokens.tenant_id) {
+	if (typeof tokens.tenant_id === 'number') {
 		cookies.set('sso_tenant_id', String(tokens.tenant_id), {
 			path: '/',
 			httpOnly: true,
@@ -171,7 +183,7 @@ export const load: PageServerLoad = async ({ url, cookies }) => {
 		await fetch(`${internalApiUrl}/v1/auth/lazy-link`, {
 			method: 'POST',
 			headers: {
-				'Authorization': `Bearer ${tokens.access_token}`,
+				'Authorization': `Bearer ${tokens.access_token as string}`,
 				'Content-Type': 'application/json',
 			},
 		}).catch(() => {});