initial commit

server/utils/auth.ts

@@ -0,0 +1,36 @@
+import type { H3Event } from 'h3'
+
+interface DiarySession {
+  unlocked?: boolean
+}
+
+const SESSION_MAX_AGE_S = 60 * 60 * 24 * 30
+
+export function diarySession(event: H3Event) {
+  const { sessionSecret } = useRuntimeConfig(event)
+  if (!sessionSecret || sessionSecret.length < 32) {
+    throw createError({ statusCode: 500, statusMessage: 'NUXT_SESSION_SECRET must be set (at least 32 characters)' })
+  }
+  return useSession<DiarySession>(event, {
+    name: 'diary',
+    password: sessionSecret,
+    maxAge: SESSION_MAX_AGE_S,
+    cookie: { httpOnly: true, sameSite: 'lax', secure: !import.meta.dev }
+  })
+}
+
+async function sha256(text: string): Promise<Uint8Array> {
+  return new Uint8Array(await crypto.subtle.digest('SHA-256', new TextEncoder().encode(text)))
+}
+
+export async function passwordMatches(event: H3Event, guess: string): Promise<boolean> {
+  const { diaryPassword } = useRuntimeConfig(event)
+  if (!diaryPassword) {
+    throw createError({ statusCode: 500, statusMessage: 'NUXT_DIARY_PASSWORD is not set' })
+  }
+
+  const [a, b] = await Promise.all([sha256(guess), sha256(diaryPassword)])
+  let difference = 0
+  for (let i = 0; i < a.length; i++) difference |= a[i]! ^ b[i]!
+  return difference === 0
+}