Crypto

The primitives an MTProto client and the tdata format need, all on the Rust core. createCryptoProvider() in opentele2/mtcute wraps them as an mtcute ICryptoProvider.

index.d.ts


function aesIgeEncrypt(data: Uint8Array, key: Uint8Array, iv: Uint8Array): Buffer
function aesIgeDecrypt(data: Uint8Array, key: Uint8Array, iv: Uint8Array): Buffer
 
class AesCtr {
  constructor(key: Uint8Array, iv: Uint8Array)
  process(data: Uint8Array): Buffer
}
 
function sha1(data: Uint8Array): Buffer
function sha256(data: Uint8Array): Buffer
function hmacSha256(key: Uint8Array, data: Uint8Array): Buffer
function pbkdf2(password: string | Uint8Array, salt: Uint8Array, iterations: number,
  keyLen?: number | null, digest?: string | null): Promise<Buffer>
 
function createLocalKey(passcode: string | Uint8Array, salt: Uint8Array): Promise<Buffer>
function createLegacyLocalKey(passcode: string | Uint8Array, salt: Uint8Array): Promise<Buffer>
function argon2id(passcode: string | Uint8Array, salt: Uint8Array, memoryKib: number,
  time: number, lanes: number): Promise<Buffer>
 
function factorizePq(pq: Uint8Array): [Buffer, Buffer]
function gzip(data: Uint8Array, maxSize?: number | null): Buffer | null
function gunzip(data: Uint8Array): Buffer
function randomBytes(size: number): Buffer
function randomFill(buf: Uint8Array): void

Name	Description
`aesIgeEncrypt`, `aesIgeDecrypt`	AES-256-IGE; `data` must be whole 16-byte blocks and `key` and `iv` 32 bytes each, otherwise `OT_BAD_LENGTH`.
`AesCtr`	An AES-256-CTR keystream (OpenSSL `aes-256-ctr`: the 16-byte IV is a 128-bit big-endian counter) under a 32-byte key; it continues across `process` calls, and encryption and decryption are the same operation.
`sha1`, `sha256`	The 20-byte SHA-1 and 32-byte SHA-256 of `data`.
`hmacSha256(key, data)`	The 32-byte HMAC-SHA256 of `data` under a key of any length; the key comes first.
`pbkdf2(...)`	PBKDF2 of `keyLen` bytes (default 64) over the HMAC of `digest`: `"sha1"`, `"sha256"` or `"sha512"` (the default). Zero iterations or another digest rejects with `OT_INVALID_INPUT`.
`createLocalKey(passcode, salt)`	The 256-byte Telegram Desktop local key (`Storage::CreateLocalKey`).
`createLegacyLocalKey(passcode, salt)`	The 256-byte legacy local key (`Storage::CreateLegacyLocalKey`).
`argon2id(...)`	A 256-byte Argon2id (version 0x13) passcode wrap key; `memoryKib` is the memory cost, `time` the passes, `lanes` the parallelism. An empty passcode, a salt under 8 bytes or a cost above its cap rejects with `OT_BAD_LENGTH`.
`factorizePq(pq)`	The factors `[p, q]` of the MTProto `pq`, `p <= q`, as minimal big-endian bytes; `pq` is 1 to 8 bytes, and 0, 1 or a prime throws `OT_INVALID_INPUT`.
`gzip(data, maxSize)`	`data` gzipped at the default level, or `null` when the output would exceed `maxSize` bytes.
`gunzip(data)`	One decompressed gzip member; anything else throws `OT_IO`.
`randomBytes(size)`, `randomFill(buf)`	Bytes from the operating system’s CSPRNG.

A string passcode or password is UTF-8 encoded. The key derivations run as async tasks off the main thread.