src/crypto/crypto_cipher.cc

#include "crypto/crypto_cipher.h"
#include "base_object-inl.h"
#include "crypto/crypto_util.h"
#include "env-inl.h"
#include "memory_tracker-inl.h"
#include "node_buffer.h"
#include "node_internals.h"
#include "node_process-inl.h"
#include "v8.h"

namespace node {

using ncrypto::Cipher;
using ncrypto::CipherCtxPointer;
using ncrypto::ClearErrorOnReturn;
using ncrypto::Digest;
using ncrypto::EVPKeyCtxPointer;
using ncrypto::EVPKeyPointer;
using ncrypto::MarkPopErrorOnReturn;
using ncrypto::SSLCtxPointer;
using ncrypto::SSLPointer;
using v8::Array;
using v8::ArrayBuffer;
using v8::BackingStore;
using v8::BackingStoreInitializationMode;
using v8::Context;
using v8::DictionaryTemplate;
using v8::FunctionCallbackInfo;
using v8::FunctionTemplate;
using v8::HandleScope;
using v8::Int32;
using v8::Isolate;
using v8::Local;
using v8::LocalVector;
using v8::MaybeLocal;
using v8::Object;
using v8::Uint32;
using v8::Undefined;
using v8::Value;

namespace crypto {
namespace {
// Collects and returns information on the given cipher
void GetCipherInfo(const FunctionCallbackInfo<Value>& args) {
  Environment* env = Environment::GetCurrent(args);

  auto tmpl = env->cipherinfo_detail_template();
  if (tmpl.IsEmpty()) {
    static constexpr std::string_view names[] = {
        "mode",
        "name",
        "nid",
        "keyLength",
        "blockSize",
        "ivLength",
    };
    tmpl = DictionaryTemplate::New(env->isolate(), names);
    env->set_cipherinfo_detail_template(tmpl);
  }
  MaybeLocal<Value> values[] = {
      Undefined(env->isolate()),  // mode
      Undefined(env->isolate()),  // name
      Undefined(env->isolate()),  // nid
      Undefined(env->isolate()),  // keyLength
      Undefined(env->isolate()),  // blockSize
      Undefined(env->isolate()),  // ivLength
  };

  CHECK(args[0]->IsString() || args[0]->IsInt32());

  const auto cipher = ([&] {
    if (args[0]->IsString()) {
      Utf8Value name(env->isolate(), args[0]);
      return Cipher::FromName(*name);
    } else {
      int nid = args[0].As<Int32>()->Value();
      return Cipher::FromNid(nid);
    }
  })();

  if (!cipher) return;

  size_t iv_length = cipher.getIvLength();
  size_t key_length = cipher.getKeyLength();

  // If the testKeyLen and testIvLen arguments are specified,
  // then we will make an attempt to see if they are usable for
  // the cipher in question, returning undefined if they are not.
  // If they are, the info object will be returned with the values
  // given.
  if (args[1]->IsUint32() || args[2]->IsUint32()) {
    // Test and input IV or key length to determine if it's acceptable.
    // If it is, then the getCipherInfo will succeed with the given
    // values.
    auto ctx = CipherCtxPointer::New();
    if (!ctx.init(cipher, true)) {
      return;
    }

    if (args[1]->IsUint32()) {
      size_t check_len = args[1].As<Uint32>()->Value();
      if (!ctx.setKeyLength(check_len)) {
        return;
      }
      key_length = check_len;
    }

    if (args[2]->IsUint32()) {
      size_t check_len = args[2].As<Uint32>()->Value();
      // For CCM modes, the IV may be between 7 and 13 bytes.
      // For GCM and OCB modes, we'll check by attempting to
      // set the value. For everything else, just check that
      // check_len == iv_length.

      if (cipher.isCcmMode()) {
        if (check_len < 7 || check_len > 13) return;
      } else if (cipher.isGcmMode()) {
        // Nothing to do.
      } else if (cipher.isOcbMode()) {
        if (!ctx.setIvLength(check_len)) return;
      } else {
        if (check_len != iv_length) return;
      }

      iv_length = check_len;
    }
  }

  // Lowercase the name in place before we create the JS string from it.
  std::string name_str(cipher.getName());
  name_str = ToLower(name_str);

  values[0] = ToV8Value(env->context(), cipher.getModeLabel(), env->isolate());
  values[1] = ToV8Value(env->context(), name_str, env->isolate());
  values[2] = Uint32::NewFromUnsigned(env->isolate(), cipher.getNid());
  values[3] = Uint32::NewFromUnsigned(env->isolate(), key_length);

  // Stream ciphers do not have a meaningful block size
  if (!cipher.isStreamMode()) {
    values[4] = Uint32::NewFromUnsigned(env->isolate(), cipher.getBlockSize());
  }

  // Ciphers that do not use an IV shouldn't report a length
  if (iv_length != 0) {
    values[5] = Uint32::NewFromUnsigned(env->isolate(), iv_length);
  }

  Local<Object> info;
  if (NewDictionaryInstanceNullProto(env->context(), tmpl, values)
          .ToLocal(&info)) {
    args.GetReturnValue().Set(info);
  }
}
}  // namespace

void CipherBase::GetSSLCiphers(const FunctionCallbackInfo<Value>& args) {
  ClearErrorOnReturn clear_error_on_return;
  Environment* env = Environment::GetCurrent(args);

  auto ctx = SSLCtxPointer::New();
  if (!ctx) {
    return ThrowCryptoError(
        env, clear_error_on_return.peekError(), "SSL_CTX_new");
  }

  auto ssl = SSLPointer::New(ctx);
  if (!ssl) {
    return ThrowCryptoError(env, clear_error_on_return.peekError(), "SSL_new");
  }

  LocalVector<Value> arr(env->isolate());
  ssl.getCiphers([&](const std::string_view name) {
    arr.push_back(OneByteString(env->isolate(), name.data(), name.length()));
  });

  args.GetReturnValue().Set(Array::New(env->isolate(), arr.data(), arr.size()));
}

void CipherBase::GetCiphers(const FunctionCallbackInfo<Value>& args) {
  Environment* env = Environment::GetCurrent(args);
  LocalVector<Value> ciphers(env->isolate());
  bool errored = false;
  Cipher::ForEach([&](std::string_view name) {
    // If a prior iteration errored, do nothing further. We apparently
    // can't actually stop openssl from stopping its iteration here.
    // But why does it matter? Good question.
    if (errored) return;
    Local<Value> val;
    if (!ToV8Value(env->context(), name, env->isolate()).ToLocal(&val)) {
      errored = true;
      return;
    }
    ciphers.push_back(val);
  });

  // If errored is true here, then we encountered a JavaScript error
  // while trying to create the V8 String from the std::string_view
  // in the iteration callback. That means we need to throw.
  if (!errored) {
    args.GetReturnValue().Set(
        Array::New(env->isolate(), ciphers.data(), ciphers.size()));
  }
}

CipherBase::CipherBase(Environment* env,
                       Local<Object> wrap,
                       CipherKind kind)
    : BaseObject(env, wrap),
      ctx_(nullptr),
      kind_(kind),
      auth_tag_state_(kAuthTagUnknown),
      auth_tag_len_(kNoAuthTagLength),
      pending_auth_failed_(false) {
  MakeWeak();
}

void CipherBase::MemoryInfo(MemoryTracker* tracker) const {
  tracker->TrackFieldWithSize("context", ctx_ ? kSizeOf_EVP_CIPHER_CTX : 0);
}

void CipherBase::Initialize(Environment* env, Local<Object> target) {
  Isolate* isolate = env->isolate();
  Local<Context> context = env->context();

  Local<FunctionTemplate> t = NewFunctionTemplate(isolate, New);

  t->InstanceTemplate()->SetInternalFieldCount(CipherBase::kInternalFieldCount);

  SetProtoMethod(isolate, t, "update", Update);
  SetProtoMethod(isolate, t, "final", Final);
  SetProtoMethod(isolate, t, "setAutoPadding", SetAutoPadding);
  SetProtoMethodNoSideEffect(isolate, t, "getAuthTag", GetAuthTag);
  SetProtoMethod(isolate, t, "setAuthTag", SetAuthTag);
  SetProtoMethod(isolate, t, "setAAD", SetAAD);
  SetConstructorFunction(context, target, "CipherBase", t);

  SetMethodNoSideEffect(context, target, "getSSLCiphers", GetSSLCiphers);
  SetMethodNoSideEffect(context, target, "getCiphers", GetCiphers);

  SetMethod(context,
            target,
            "publicEncrypt",
            PublicKeyCipher::Cipher<PublicKeyCipher::kPublic,
                                    ncrypto::Cipher::encrypt>);
  SetMethod(context,
            target,
            "privateDecrypt",
            PublicKeyCipher::Cipher<PublicKeyCipher::kPrivate,
                                    ncrypto::Cipher::decrypt>);
  SetMethod(context,
            target,
            "privateEncrypt",
            PublicKeyCipher::Cipher<PublicKeyCipher::kPrivate,
                                    ncrypto::Cipher::sign>);
  SetMethod(context,
            target,
            "publicDecrypt",
            PublicKeyCipher::Cipher<PublicKeyCipher::kPublic,
                                    ncrypto::Cipher::recover>);

  SetMethodNoSideEffect(context, target, "getCipherInfo", GetCipherInfo);

  NODE_DEFINE_CONSTANT(target, kWebCryptoCipherEncrypt);
  NODE_DEFINE_CONSTANT(target, kWebCryptoCipherDecrypt);
}

void CipherBase::RegisterExternalReferences(
    ExternalReferenceRegistry* registry) {
  registry->Register(New);

  registry->Register(Update);
  registry->Register(Final);
  registry->Register(SetAutoPadding);
  registry->Register(GetAuthTag);
  registry->Register(SetAuthTag);
  registry->Register(SetAAD);

  registry->Register(GetSSLCiphers);
  registry->Register(GetCiphers);

  registry->Register(PublicKeyCipher::Cipher<PublicKeyCipher::kPublic,
                                             ncrypto::Cipher::encrypt>);
  registry->Register(PublicKeyCipher::Cipher<PublicKeyCipher::kPrivate,
                                             ncrypto::Cipher::decrypt>);
  registry->Register(PublicKeyCipher::Cipher<PublicKeyCipher::kPrivate,
                                             ncrypto::Cipher::sign>);
  registry->Register(PublicKeyCipher::Cipher<PublicKeyCipher::kPublic,
                                             ncrypto::Cipher::recover>);

  registry->Register(GetCipherInfo);
}

void CipherBase::New(const FunctionCallbackInfo<Value>& args) {
  CHECK(args.IsConstructCall());
  Environment* env = Environment::GetCurrent(args);
  CHECK_EQ(args.Length(), 5);

  CipherBase* cipher =
      new CipherBase(env, args.This(), args[0]->IsTrue() ? kCipher : kDecipher);

  const Utf8Value cipher_type(env->isolate(), args[1]);

  // The argument can either be a KeyObjectHandle or a byte source
  // (e.g. ArrayBuffer, TypedArray, etc). Whichever it is, grab the
  // raw bytes and proceed...
  const ByteSource key_buf = ByteSource::FromSecretKeyBytes(env, args[2]);

  if (key_buf.size() > INT_MAX) [[unlikely]] {
    return THROW_ERR_OUT_OF_RANGE(env, "key is too big");
  }

  ArrayBufferOrViewContents<unsigned char> iv_buf(
      !args[3]->IsNull() ? args[3] : Local<Value>());

  if (!iv_buf.CheckSizeInt32()) [[unlikely]] {
    return THROW_ERR_OUT_OF_RANGE(env, "iv is too big");
  }
  // Don't assign to cipher->auth_tag_len_ directly; the value might not
  // represent a valid length at this point.
  unsigned int auth_tag_len;
  if (args[4]->IsUint32()) {
    auth_tag_len = args[4].As<Uint32>()->Value();
  } else {
    CHECK(args[4]->IsInt32() && args[4].As<Int32>()->Value() == -1);
    auth_tag_len = kNoAuthTagLength;
  }

  cipher->InitIv(*cipher_type, key_buf, iv_buf, auth_tag_len);
}

void CipherBase::CommonInit(const char* cipher_type,
                            const ncrypto::Cipher& cipher,
                            const unsigned char* key,
                            int key_len,
                            const unsigned char* iv,
                            int iv_len,
                            unsigned int auth_tag_len) {
  MarkPopErrorOnReturn mark_pop_error_on_return;
  CHECK(!ctx_);
  ctx_ = CipherCtxPointer::New();
  CHECK(ctx_);

  if (cipher.isWrapMode()) {
    ctx_.setAllowWrap();
  }

  const bool encrypt = (kind_ == kCipher);
  if (!ctx_.init(cipher, encrypt)) {
    return ThrowCryptoError(env(),
                            mark_pop_error_on_return.peekError(),
                            "Failed to initialize cipher");
  }

  if (cipher.isSupportedAuthenticatedMode()) {
    CHECK_GE(iv_len, 0);
    if (!InitAuthenticated(cipher_type, iv_len, auth_tag_len)) {
      return;
    }
  }

  if (!ctx_.setKeyLength(key_len)) {
    ctx_.reset();
    return THROW_ERR_CRYPTO_INVALID_KEYLEN(env());
  }

  if (!ctx_.init(Cipher(), encrypt, key, iv)) {
    return ThrowCryptoError(env(),
                            mark_pop_error_on_return.peekError(),
                            "Failed to initialize cipher");
  }
}

void CipherBase::InitIv(const char* cipher_type,
                        const ByteSource& key_buf,
                        const ArrayBufferOrViewContents<unsigned char>& iv_buf,
                        unsigned int auth_tag_len) {
  HandleScope scope(env()->isolate());
  MarkPopErrorOnReturn mark_pop_error_on_return;

  auto cipher = Cipher::FromName(cipher_type);
  if (!cipher) return THROW_ERR_CRYPTO_UNKNOWN_CIPHER(env());

  const int expected_iv_len = cipher.getIvLength();
  const bool has_iv = iv_buf.size() > 0;

  // Throw if no IV was passed and the cipher requires an IV
  if (!has_iv && expected_iv_len != 0) {
    return THROW_ERR_CRYPTO_INVALID_IV(env());
  }

  // Throw if an IV was passed which does not match the cipher's fixed IV length
  // static_cast<int> for the iv_buf.size() is safe because we've verified
  // prior that the value is not larger than INT_MAX.
  if (!cipher.isSupportedAuthenticatedMode() && has_iv &&
      static_cast<int>(iv_buf.size()) != expected_iv_len) {
    return THROW_ERR_CRYPTO_INVALID_IV(env());
  }

  if (cipher.isChaCha20Poly1305()) {
    CHECK(has_iv);
    // Check for invalid IV lengths, since OpenSSL does not under some
    // conditions:
    //   https://www.openssl.org/news/secadv/20190306.txt.
    if (iv_buf.size() > 12) {
      return THROW_ERR_CRYPTO_INVALID_IV(env());
    }
  }

  CommonInit(
      cipher_type,
      cipher,
      key_buf.data<unsigned char>(),
      key_buf.size(),
      iv_buf.data(),
      iv_buf.size(),
      auth_tag_len);
}

bool CipherBase::InitAuthenticated(const char* cipher_type,
                                   int iv_len,
                                   unsigned int auth_tag_len) {
  CHECK(IsAuthenticatedMode());
  MarkPopErrorOnReturn mark_pop_error_on_return;

  if (!ctx_.setIvLength(iv_len)) {
    THROW_ERR_CRYPTO_INVALID_IV(env());
    return false;
  }

  if (ctx_.isGcmMode()) {
    if (auth_tag_len != kNoAuthTagLength) {
      if (!Cipher::IsValidGCMTagLength(auth_tag_len)) {
        THROW_ERR_CRYPTO_INVALID_AUTH_TAG(
          env(),
          "Invalid authentication tag length: %u",
          auth_tag_len);
        return false;
      }

      // Remember the given authentication tag length for later.
      auth_tag_len_ = auth_tag_len;
    }
  } else {
    if (auth_tag_len == kNoAuthTagLength) {
      // We treat ChaCha20-Poly1305 specially. Like GCM, the authentication tag
      // length defaults to 16 bytes when encrypting. Unlike GCM, the
      // authentication tag length also defaults to 16 bytes when decrypting,
      // whereas GCM would accept any valid authentication tag length.
      if (ctx_.isChaCha20Poly1305()) {
        auth_tag_len = EVP_CHACHAPOLY_TLS_TAG_LEN;
      } else {
        THROW_ERR_CRYPTO_INVALID_AUTH_TAG(
          env(), "authTagLength required for %s", cipher_type);
        return false;
      }
    }

    // TODO(tniessen) Support CCM decryption in FIPS mode

    if (ctx_.isCcmMode() && kind_ == kDecipher && ncrypto::isFipsEnabled()) {
      THROW_ERR_CRYPTO_UNSUPPORTED_OPERATION(env(),
          "CCM encryption not supported in FIPS mode");
      return false;
    }

    // Tell OpenSSL about the desired length.
    if (!ctx_.setAeadTagLength(auth_tag_len)) {
      THROW_ERR_CRYPTO_INVALID_AUTH_TAG(
          env(), "Invalid authentication tag length: %u", auth_tag_len);
      return false;
    }

    // Remember the given authentication tag length for later.
    auth_tag_len_ = auth_tag_len;

    if (ctx_.isCcmMode()) {
      // Restrict the message length to min(INT_MAX, 2^(8*(15-iv_len))-1) bytes.
      CHECK(iv_len >= 7 && iv_len <= 13);
      max_message_size_ = INT_MAX;
      if (iv_len == 12) max_message_size_ = 16777215;
      if (iv_len == 13) max_message_size_ = 65535;
    }
  }

  return true;
}

bool CipherBase::CheckCCMMessageLength(int message_len) {
  CHECK(ctx_);
  CHECK(ctx_.isCcmMode());

  if (message_len > max_message_size_) {
    THROW_ERR_CRYPTO_INVALID_MESSAGELEN(env());
    return false;
  }

  return true;
}

bool CipherBase::IsAuthenticatedMode() const {
  // Check if this cipher operates in an AEAD mode that we support.
  CHECK(ctx_);
  return ncrypto::Cipher::FromCtx(ctx_).isSupportedAuthenticatedMode();
}

void CipherBase::GetAuthTag(const FunctionCallbackInfo<Value>& args) {
  Environment* env = Environment::GetCurrent(args);
  CipherBase* cipher;
  ASSIGN_OR_RETURN_UNWRAP(&cipher, args.This());

  // Only callable after Final and if encrypting.
  if (cipher->ctx_ || cipher->kind_ != kCipher ||
      cipher->auth_tag_len_ == kNoAuthTagLength ||
      cipher->auth_tag_state_ != kAuthTagComputed) {
    return;
  }

  Local<Value> ret;
  if (Buffer::Copy(env, cipher->auth_tag_, cipher->auth_tag_len_)
          .ToLocal(&ret)) {
    args.GetReturnValue().Set(ret);
  }
}

void CipherBase::SetAuthTag(const FunctionCallbackInfo<Value>& args) {
  CipherBase* cipher;
  ASSIGN_OR_RETURN_UNWRAP(&cipher, args.This());
  Environment* env = Environment::GetCurrent(args);

  if (!cipher->ctx_ ||
      !cipher->IsAuthenticatedMode() ||
      cipher->kind_ != kDecipher ||
      cipher->auth_tag_state_ != kAuthTagUnknown) {
    return args.GetReturnValue().Set(false);
  }

  ArrayBufferOrViewContents<char> auth_tag(args[0]);
  if (!auth_tag.CheckSizeInt32()) [[unlikely]] {
    return THROW_ERR_OUT_OF_RANGE(env, "buffer is too big");
  }
  unsigned int tag_len = auth_tag.size();

  bool is_valid;
  if (cipher->ctx_.isGcmMode()) {
    // Restrict GCM tag lengths according to NIST 800-38d, page 9.
    is_valid = (cipher->auth_tag_len_ == kNoAuthTagLength ||
                cipher->auth_tag_len_ == tag_len) &&
               Cipher::IsValidGCMTagLength(tag_len);
  } else {
    // At this point, the tag length is already known and must match the
    // length of the given authentication tag.
    CHECK(Cipher::FromCtx(cipher->ctx_).isSupportedAuthenticatedMode());
    CHECK_NE(cipher->auth_tag_len_, kNoAuthTagLength);
    is_valid = cipher->auth_tag_len_ == tag_len;
  }

  if (!is_valid) {
    return THROW_ERR_CRYPTO_INVALID_AUTH_TAG(
      env, "Invalid authentication tag length: %u", tag_len);
  }

  if (cipher->ctx_.isGcmMode() && cipher->auth_tag_len_ == kNoAuthTagLength &&
      tag_len != EVP_GCM_TLS_TAG_LEN && env->EmitProcessEnvWarning()) {
    if (ProcessEmitDeprecationWarning(
            env,
            "Using AES-GCM authentication tags of less than 128 bits without "
            "specifying the authTagLength option when initializing decryption "
            "is deprecated.",
            "DEP0182")
            .IsNothing())
      return;
  }

  cipher->auth_tag_len_ = tag_len;
  CHECK_LE(cipher->auth_tag_len_, ncrypto::Cipher::MAX_AUTH_TAG_LENGTH);

  if (!cipher->ctx_.setAeadTag({auth_tag.data(), cipher->auth_tag_len_})) {
    return args.GetReturnValue().Set(false);
  }
  cipher->auth_tag_state_ = kAuthTagSetByUser;

  args.GetReturnValue().Set(true);
}

bool CipherBase::SetAAD(
    const ArrayBufferOrViewContents<unsigned char>& data,
    int plaintext_len) {
  if (!ctx_ || !IsAuthenticatedMode())
    return false;
  MarkPopErrorOnReturn mark_pop_error_on_return;

  int outlen;

  // When in CCM mode, we need to set the authentication tag and the plaintext
  // length in advance.
  if (ctx_.isCcmMode()) {
    if (plaintext_len < 0) {
      THROW_ERR_MISSING_ARGS(env(),
          "options.plaintextLength required for CCM mode with AAD");
      return false;
    }

    if (!CheckCCMMessageLength(plaintext_len)) {
      return false;
    }

    ncrypto::Buffer<const unsigned char> buffer{
        .data = nullptr,
        .len = static_cast<size_t>(plaintext_len),
    };
    // Specify the plaintext length.
    if (!ctx_.update(buffer, nullptr, &outlen)) {
      return false;
    }
  }

  ncrypto::Buffer<const unsigned char> buffer{
      .data = data.data(),
      .len = data.size(),
  };
  return ctx_.update(buffer, nullptr, &outlen);
}

void CipherBase::SetAAD(const FunctionCallbackInfo<Value>& args) {
  CipherBase* cipher;
  ASSIGN_OR_RETURN_UNWRAP(&cipher, args.This());
  Environment* env = Environment::GetCurrent(args);

  CHECK_EQ(args.Length(), 2);
  CHECK(args[1]->IsInt32());
  int plaintext_len = args[1].As<Int32>()->Value();
  ArrayBufferOrViewContents<unsigned char> buf(args[0]);

  if (!buf.CheckSizeInt32()) [[unlikely]] {
    return THROW_ERR_OUT_OF_RANGE(env, "buffer is too big");
  }
  args.GetReturnValue().Set(cipher->SetAAD(buf, plaintext_len));
}

CipherBase::UpdateResult CipherBase::Update(
    const char* data,
    size_t len,
    std::unique_ptr<BackingStore>* out) {
  if (!ctx_ || len > INT_MAX) return kErrorState;
  MarkPopErrorOnReturn mark_pop_error_on_return;

  if (ctx_.isCcmMode() && !CheckCCMMessageLength(len)) {
    return kErrorMessageSize;
  }

  const int block_size = ctx_.getBlockSize();
  CHECK_GT(block_size, 0);
  if (len + block_size > INT_MAX) return kErrorState;
  int buf_len = len + block_size;

  ncrypto::Buffer<const unsigned char> buffer = {
      .data = reinterpret_cast<const unsigned char*>(data),
      .len = len,
  };
  if (kind_ == kCipher && ctx_.isWrapMode() &&
      !ctx_.update(buffer, nullptr, &buf_len)) {
    return kErrorState;
  }

  *out = ArrayBuffer::NewBackingStore(
      env()->isolate(),
      buf_len,
      BackingStoreInitializationMode::kUninitialized);

  buffer = {
      .data = reinterpret_cast<const unsigned char*>(data),
      .len = len,
  };

  bool r = ctx_.update(
      buffer, static_cast<unsigned char*>((*out)->Data()), &buf_len);

  CHECK_LE(static_cast<size_t>(buf_len), (*out)->ByteLength());
  if (buf_len == 0) {
    *out = ArrayBuffer::NewBackingStore(env()->isolate(), 0);
  } else if (static_cast<size_t>(buf_len) != (*out)->ByteLength()) {
    std::unique_ptr<BackingStore> old_out = std::move(*out);
    *out = ArrayBuffer::NewBackingStore(
        env()->isolate(),
        buf_len,
        BackingStoreInitializationMode::kUninitialized);
    memcpy((*out)->Data(), old_out->Data(), buf_len);
  }

  // When in CCM mode, EVP_CipherUpdate will fail if the authentication tag is
  // invalid. In that case, remember the error and throw in final().
  if (!r && kind_ == kDecipher && ctx_.isCcmMode()) {
    pending_auth_failed_ = true;
    return kSuccess;
  }
  return r == 1 ? kSuccess : kErrorState;
}

void CipherBase::Update(const FunctionCallbackInfo<Value>& args) {
  Decode<CipherBase>(
      args,
      [](CipherBase* cipher,
         const FunctionCallbackInfo<Value>& args,
         const char* data,
         size_t size) {
        MarkPopErrorOnReturn mark_pop_error_on_return;
        std::unique_ptr<BackingStore> out;
        Environment* env = Environment::GetCurrent(args);

        if (size > INT_MAX) [[unlikely]] {
          return THROW_ERR_OUT_OF_RANGE(env, "data is too long");
        }
        UpdateResult r = cipher->Update(data, size, &out);

        if (r != kSuccess) {
          if (r == kErrorState) {
            ThrowCryptoError(env,
                             mark_pop_error_on_return.peekError(),
                             "Trying to add data in unsupported state");
          }
          return;
        }

        auto ab = ArrayBuffer::New(env->isolate(), std::move(out));
        args.GetReturnValue().Set(Buffer::New(env, ab, 0, ab->ByteLength())
                                      .FromMaybe(Local<Value>()));
      });
}

bool CipherBase::SetAutoPadding(bool auto_padding) {
  if (!ctx_) return false;
  MarkPopErrorOnReturn mark_pop_error_on_return;
  return ctx_.setPadding(auto_padding);
}

void CipherBase::SetAutoPadding(const FunctionCallbackInfo<Value>& args) {
  CipherBase* cipher;
  ASSIGN_OR_RETURN_UNWRAP(&cipher, args.This());

  bool b = cipher->SetAutoPadding(args.Length() < 1 || args[0]->IsTrue());
  args.GetReturnValue().Set(b);  // Possibly report invalid state failure
}

bool CipherBase::Final(std::unique_ptr<BackingStore>* out) {
  if (!ctx_) return false;

  *out = ArrayBuffer::NewBackingStore(
      env()->isolate(),
      static_cast<size_t>(ctx_.getBlockSize()),
      BackingStoreInitializationMode::kUninitialized);

#if (OPENSSL_VERSION_NUMBER < 0x30000000L)
  // OpenSSL v1.x doesn't verify the presence of the auth tag so do
  // it ourselves, see https://github.com/nodejs/node/issues/45874.
  if (kind_ == kDecipher && ctx_.isChaCha20Poly1305() &&
      auth_tag_state_ != kAuthTagSetByUser) {
    return false;
  }
#endif

  // In CCM mode, final() only checks whether authentication failed in update().
  // EVP_CipherFinal_ex must not be called and will fail.
  bool ok;
  if (kind_ == kDecipher && ctx_.isCcmMode()) {
    ok = !pending_auth_failed_;
    *out = ArrayBuffer::NewBackingStore(env()->isolate(), 0);
  } else {
    int out_len = (*out)->ByteLength();
    ok = ctx_.update(
        {}, static_cast<unsigned char*>((*out)->Data()), &out_len, true);

    CHECK_LE(static_cast<size_t>(out_len), (*out)->ByteLength());
    if (out_len == 0) {
      *out = ArrayBuffer::NewBackingStore(env()->isolate(), 0);
    } else if (static_cast<size_t>(out_len) != (*out)->ByteLength()) {
      std::unique_ptr<BackingStore> old_out = std::move(*out);
      *out = ArrayBuffer::NewBackingStore(
          env()->isolate(),
          out_len,
          BackingStoreInitializationMode::kUninitialized);
      memcpy((*out)->Data(), old_out->Data(), out_len);
    }

    if (ok && kind_ == kCipher && IsAuthenticatedMode()) {
      // In GCM mode, the authentication tag length can be specified in advance,
      // but defaults to 16 bytes when encrypting. In CCM and OCB mode, it must
      // always be given by the user.
      if (auth_tag_len_ == kNoAuthTagLength) {
        CHECK(ctx_.isGcmMode());
        auth_tag_len_ = EVP_GCM_TLS_TAG_LEN;
      }
      ok = ctx_.getAeadTag(auth_tag_len_,
                           reinterpret_cast<unsigned char*>(auth_tag_));
      if (ok) {
        auth_tag_state_ = kAuthTagComputed;
      }
    }
  }

  ctx_.reset();

  return ok;
}

void CipherBase::Final(const FunctionCallbackInfo<Value>& args) {
  Environment* env = Environment::GetCurrent(args);
  MarkPopErrorOnReturn mark_pop_error_on_return;

  CipherBase* cipher;
  ASSIGN_OR_RETURN_UNWRAP(&cipher, args.This());
  if (cipher->ctx_ == nullptr) {
    return THROW_ERR_CRYPTO_INVALID_STATE(env);
  }

  std::unique_ptr<BackingStore> out;

  // Check IsAuthenticatedMode() first, Final() destroys the EVP_CIPHER_CTX.
  const bool is_auth_mode = cipher->IsAuthenticatedMode();
  bool r = cipher->Final(&out);

  if (!r) {
    const char* msg = is_auth_mode
                          ? "Unsupported state or unable to authenticate data"
                          : "Unsupported state";

    return ThrowCryptoError(env, mark_pop_error_on_return.peekError(), msg);
  }

  auto ab = ArrayBuffer::New(env->isolate(), std::move(out));
  args.GetReturnValue().Set(
      Buffer::New(env, ab, 0, ab->ByteLength()).FromMaybe(Local<Value>()));
}

template <PublicKeyCipher::Cipher_t cipher>
bool PublicKeyCipher::Cipher(
    Environment* env,
    const EVPKeyPointer& pkey,
    int padding,
    const Digest& digest,
    const ArrayBufferOrViewContents<unsigned char>& oaep_label,
    const ArrayBufferOrViewContents<unsigned char>& data,
    std::unique_ptr<BackingStore>* out) {
  auto label = oaep_label.ToByteSource();
  auto in = data.ToByteSource();

  const ncrypto::Cipher::CipherParams params{
      .padding = padding,
      .digest = digest,
      .label = label,
  };

  auto buf = cipher(pkey, params, in);

  if (!buf) return false;

  if (buf.size() == 0) {
    *out = ArrayBuffer::NewBackingStore(env->isolate(), 0);
  } else {
    *out = ArrayBuffer::NewBackingStore(
        env->isolate(),
        buf.size(),
        BackingStoreInitializationMode::kUninitialized);
    memcpy((*out)->Data(), buf.get(), buf.size());
  }

  return true;
}

template <PublicKeyCipher::Operation operation,
          PublicKeyCipher::Cipher_t cipher>
void PublicKeyCipher::Cipher(const FunctionCallbackInfo<Value>& args) {
  MarkPopErrorOnReturn mark_pop_error_on_return;
  Environment* env = Environment::GetCurrent(args);

  unsigned int offset = 0;
  auto data = KeyObjectData::GetPublicOrPrivateKeyFromJs(args, &offset);
  if (!data) return;
  const auto& pkey = data.GetAsymmetricKey();
  if (!pkey) return;

  ArrayBufferOrViewContents<unsigned char> buf(args[offset]);
  if (!buf.CheckSizeInt32()) [[unlikely]] {
    return THROW_ERR_OUT_OF_RANGE(env, "buffer is too long");
  }
  uint32_t padding;
  if (!args[offset + 1]->Uint32Value(env->context()).To(&padding)) return;

  if (cipher == ncrypto::Cipher::decrypt &&
      operation == PublicKeyCipher::kPrivate && padding == RSA_PKCS1_PADDING) {
    EVPKeyCtxPointer ctx = pkey.newCtx();
    CHECK(ctx);

    if (!ctx.initForDecrypt()) {
      return ThrowCryptoError(env, ERR_get_error());
    }

    // RSA implicit rejection here is not supported by BoringSSL.
    if (!ctx.setRsaImplicitRejection()) [[unlikely]] {
      return THROW_ERR_INVALID_ARG_VALUE(
          env,
          "RSA_PKCS1_PADDING is no longer supported for private decryption");
    }
  }

  Digest digest;
  if (args[offset + 2]->IsString()) {
    Utf8Value oaep_str(env->isolate(), args[offset + 2]);
    digest = Digest::FromName(*oaep_str);
    if (!digest) return THROW_ERR_OSSL_EVP_INVALID_DIGEST(env);
  }

  ArrayBufferOrViewContents<unsigned char> oaep_label(
      !args[offset + 3]->IsUndefined() ? args[offset + 3] : Local<Value>());
  if (!oaep_label.CheckSizeInt32()) [[unlikely]] {
    return THROW_ERR_OUT_OF_RANGE(env, "oaepLabel is too big");
  }
  std::unique_ptr<BackingStore> out;
  if (!Cipher<cipher>(env, pkey, padding, digest, oaep_label, buf, &out)) {
    return ThrowCryptoError(env, ERR_get_error());
  }

  Local<ArrayBuffer> ab = ArrayBuffer::New(env->isolate(), std::move(out));
  args.GetReturnValue().Set(
      Buffer::New(env, ab, 0, ab->ByteLength()).FromMaybe(Local<Value>()));
}

}  // namespace crypto
}  // namespace node