Created
February 19, 2024 23:15
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| let __next_loaded_action_key: CryptoKey; | |
| export async function getActionEncryptionKey() { | |
| if (__next_loaded_action_key) { | |
| return __next_loaded_action_key; | |
| } | |
| const rawKey = process.env.NEXT_SERVER_ACTIONS_ENCRYPTION_KEY; | |
| if (rawKey === undefined) { | |
| throw new Error("Missing encryption key for Server Actions"); | |
| } | |
| __next_loaded_action_key = await crypto.subtle.importKey( | |
| "raw", | |
| stringToUint8Array(atob(rawKey)), | |
| "AES-GCM", | |
| true, | |
| ["encrypt", "decrypt"] | |
| ); | |
| return __next_loaded_action_key; | |
| } | |
| const textDecoder = new TextDecoder(); | |
| export function stringToUint8Array(binary: string) { | |
| const len = binary.length; | |
| const arr = new Uint8Array(len); | |
| for (let i = 0; i < len; i++) { | |
| arr[i] = binary.charCodeAt(i); | |
| } | |
| return arr; | |
| } | |
| export function encrypt(key: CryptoKey, iv: Uint8Array, data: Uint8Array) { | |
| return crypto.subtle.encrypt( | |
| { | |
| name: "AES-GCM", | |
| iv, | |
| }, | |
| key, | |
| data | |
| ); | |
| } | |
| export function decrypt(key: CryptoKey, iv: Uint8Array, data: Uint8Array) { | |
| return crypto.subtle.decrypt( | |
| { | |
| name: "AES-GCM", | |
| iv, | |
| }, | |
| key, | |
| data | |
| ); | |
| } | |
| async function decodeActionBoundArg(actionId: string, arg: string) { | |
| const key = await getActionEncryptionKey(); | |
| if (typeof key === "undefined") { | |
| throw new Error( | |
| `Missing encryption key for Server Action. This is a bug in Next.js` | |
| ); | |
| } | |
| // Get the iv (16 bytes) and the payload from the arg. | |
| const originalPayload = atob(arg); | |
| const ivValue = originalPayload.slice(0, 16); | |
| const payload = originalPayload.slice(16); | |
| if (payload === undefined) { | |
| throw new Error("Invalid Server Action payload."); | |
| } | |
| const decrypted = textDecoder.decode( | |
| await decrypt(key, stringToUint8Array(ivValue), stringToUint8Array(payload)) | |
| ); | |
| if (!decrypted.startsWith(actionId)) { | |
| throw new Error("Invalid Server Action payload: failed to decrypt."); | |
| } | |
| return decrypted.slice(actionId.length); | |
| } | |
| function arrayBufferToString(buffer: ArrayBuffer) { | |
| const bytes = new Uint8Array(buffer); | |
| const len = bytes.byteLength; | |
| // @anonrig: V8 has a limit of 65535 arguments in a function. | |
| // For len < 65535, this is faster. | |
| // https://github.com/vercel/next.js/pull/56377#pullrequestreview-1656181623 | |
| if (len < 65535) { | |
| return String.fromCharCode.apply(null, bytes as unknown as number[]); | |
| } | |
| let binary = ""; | |
| for (let i = 0; i < len; i++) { | |
| binary += String.fromCharCode(bytes[i]); | |
| } | |
| return binary; | |
| } | |
| async function generateRandomActionKeyRaw(dev?: boolean) { | |
| const key = await crypto.subtle.generateKey( | |
| { | |
| name: "AES-GCM", | |
| length: 256, | |
| }, | |
| true, | |
| ["encrypt", "decrypt"] | |
| ); | |
| const exported = await crypto.subtle.exportKey("raw", key); | |
| const b64 = btoa(arrayBufferToString(exported)); | |
| __next_loaded_action_key = key; | |
| return b64; | |
| } |
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