function tlsRecord
tlsRecord(): Coder<TlsRecord>

Creates a coder for a TLS record layer header and fragment (RFC 8446 section 5.1).

The fragment's length is derived from the header's length field (fragment.length === length), so length must match the fragment you provide when encoding — nothing recomputes it for you. The fragment is treated as opaque bytes: this coder does not parse handshake messages, validate content types or versions, decompress, or decrypt.

Examples

Decode a known ClientHello-shaped record header

import { assertEquals } from "@std/assert";
import { tlsRecord, TLS_CONTENT_TYPE, TLS_VERSION } from "@binstruct/tls-record";

// deno-fmt-ignore
const wire = new Uint8Array([
  0x16,       // type = handshake
  0x03, 0x01, // legacyVersion = TLS 1.0
  0x00, 0x02, // length = 2
  0xde, 0xad, // fragment
]);

const [decoded, read] = tlsRecord().decode(wire);

assertEquals(read, wire.length);
assertEquals(decoded.contentType, TLS_CONTENT_TYPE.handshake);
assertEquals(decoded.legacyVersion, TLS_VERSION.TLS1_0);
assertEquals(decoded.length, 2);
assertEquals(decoded.fragment, new Uint8Array([0xde, 0xad]));

Empty application data record

import { assertEquals } from "@std/assert";
import { tlsRecord, TLS_CONTENT_TYPE, TLS_RECORD_HEADER_SIZE, TLS_VERSION } from "@binstruct/tls-record";

const coder = tlsRecord();
const buffer = new Uint8Array(TLS_RECORD_HEADER_SIZE);
const written = coder.encode({
  contentType: TLS_CONTENT_TYPE.applicationData,
  legacyVersion: TLS_VERSION.TLS1_2,
  length: 0,
  fragment: new Uint8Array(0),
}, buffer);
const [decoded] = coder.decode(buffer);

assertEquals(written, TLS_RECORD_HEADER_SIZE);
assertEquals(decoded.fragment.length, 0);

Return Type

Coder<TlsRecord>

A coder for TlsRecord values.

Usage

import { tlsRecord } from ".";