decaps static method

Uint8List decaps(List<int> privateKey, List<int> ciphertext)

Recovers the shared secret from ciphertext with privateKey, which may be either the 2400-byte expanded key or the 64-byte seed.

Implementation

static Uint8List decaps(List<int> privateKey, List<int> ciphertext) =>
    using((arena) {
      final pkey = privateKey.length == seedLength
          ? keyFromOctetParam(arena, algorithm, 'seed', privateKey)
          : rawPrivateKey(arena, algorithm, privateKey);
      final ctx = checkNotNull(
        ssl.EVP_PKEY_CTX_new_from_pkey(nullptr, pkey, nullptr),
        'EVP_PKEY_CTX_new_from_pkey',
      );
      arena.using(ctx, ssl.EVP_PKEY_CTX_free);
      checkOne(
        ssl.EVP_PKEY_decapsulate_init(ctx, nullptr),
        'EVP_PKEY_decapsulate_init',
      );
      final ssLen = arena<Size>()..value = sharedSecretLength;
      final ss = secretBuffer(arena, sharedSecretLength);
      checkOne(
        ssl.EVP_PKEY_decapsulate(
          ctx,
          ss,
          ssLen,
          toNative(arena, ciphertext),
          ciphertext.length,
        ),
        'EVP_PKEY_decapsulate',
      );
      return fromNative(ss, ssLen.value);
    });