v2.0.0
This commit is contained in:
parent
27aae99d99
commit
7bcda55ebb
3158 changed files with 140643 additions and 130380 deletions
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@ -1,249 +1,424 @@
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<?php
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namespace Aws\Crypto;
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use Aws\Exception\CryptoException;
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use GuzzleHttp\Psr7;
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use GuzzleHttp\Psr7\LimitStream;
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use Psr\Http\Message\StreamInterface;
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trait DecryptionTraitV2
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{
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/**
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* Dependency to reverse lookup the openssl_* cipher name from the AESName
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* in the MetadataEnvelope.
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*
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* @param $aesName
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*
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* @return string
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*
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* @internal
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*/
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abstract protected function getCipherFromAesName($aesName);
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/**
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* Dependency to generate a CipherMethod from a set of inputs for loading
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* in to an AesDecryptingStream.
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*
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* @param string $cipherName Name of the cipher to generate for decrypting.
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* @param string $iv Base Initialization Vector for the cipher.
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* @param int $keySize Size of the encryption key, in bits, that will be
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* used.
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*
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* @return Cipher\CipherMethod
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*
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* @internal
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*/
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abstract protected function buildCipherMethod($cipherName, $iv, $keySize);
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/**
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* Builds an AesStreamInterface using cipher options loaded from the
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* MetadataEnvelope and MaterialsProvider. Can decrypt data from both the
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* legacy and V2 encryption client workflows.
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*
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* @param string $cipherText Plain-text data to be encrypted using the
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* materials, algorithm, and data provided.
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* @param MaterialsProviderInterfaceV2 $provider A provider to supply and encrypt
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* materials used in encryption.
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* @param MetadataEnvelope $envelope A storage envelope for encryption
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* metadata to be read from.
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* @param array $options Options used for decryption.
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*
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* @return AesStreamInterface
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*
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* @throws \InvalidArgumentException Thrown when a value in $cipherOptions
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* is not valid.
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*
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* @internal
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*/
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public function decrypt(
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$cipherText,
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MaterialsProviderInterfaceV2 $provider,
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MetadataEnvelope $envelope,
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array $options = []
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) {
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$options['@CipherOptions'] = !empty($options['@CipherOptions'])
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? $options['@CipherOptions']
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: [];
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$options['@CipherOptions']['Iv'] = base64_decode(
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$envelope[MetadataEnvelope::IV_HEADER]
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);
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$options['@CipherOptions']['TagLength'] =
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$envelope[MetadataEnvelope::CRYPTO_TAG_LENGTH_HEADER] / 8;
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$cek = $provider->decryptCek(
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base64_decode(
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$envelope[MetadataEnvelope::CONTENT_KEY_V2_HEADER]
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),
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json_decode(
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$envelope[MetadataEnvelope::MATERIALS_DESCRIPTION_HEADER],
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true
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),
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$options
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);
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$options['@CipherOptions']['KeySize'] = strlen($cek) * 8;
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$options['@CipherOptions']['Cipher'] = $this->getCipherFromAesName(
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$envelope[MetadataEnvelope::CONTENT_CRYPTO_SCHEME_HEADER]
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);
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$this->validateOptionsAndEnvelope($options, $envelope);
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$decryptionStream = $this->getDecryptingStream(
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$cipherText,
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$cek,
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$options['@CipherOptions']
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);
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unset($cek);
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return $decryptionStream;
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}
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private function getTagFromCiphertextStream(
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StreamInterface $cipherText,
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$tagLength
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) {
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$cipherTextSize = $cipherText->getSize();
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if ($cipherTextSize == null || $cipherTextSize <= 0) {
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throw new \RuntimeException('Cannot decrypt a stream of unknown'
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. ' size.');
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}
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return (string) new LimitStream(
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$cipherText,
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$tagLength,
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$cipherTextSize - $tagLength
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);
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}
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private function getStrippedCiphertextStream(
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StreamInterface $cipherText,
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$tagLength
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) {
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$cipherTextSize = $cipherText->getSize();
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if ($cipherTextSize == null || $cipherTextSize <= 0) {
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throw new \RuntimeException('Cannot decrypt a stream of unknown'
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. ' size.');
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}
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return new LimitStream(
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$cipherText,
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$cipherTextSize - $tagLength,
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0
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);
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}
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private function validateOptionsAndEnvelope($options, $envelope)
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{
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$allowedCiphers = AbstractCryptoClientV2::$supportedCiphers;
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$allowedKeywraps = AbstractCryptoClientV2::$supportedKeyWraps;
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if ($options['@SecurityProfile'] == 'V2_AND_LEGACY') {
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$allowedCiphers = array_unique(array_merge(
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$allowedCiphers,
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AbstractCryptoClient::$supportedCiphers
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));
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$allowedKeywraps = array_unique(array_merge(
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$allowedKeywraps,
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AbstractCryptoClient::$supportedKeyWraps
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));
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}
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$v1SchemaException = new CryptoException("The requested object is encrypted"
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. " with V1 encryption schemas that have been disabled by"
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. " client configuration @SecurityProfile=V2. Retry with"
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. " V2_AND_LEGACY enabled or reencrypt the object.");
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if (!in_array($options['@CipherOptions']['Cipher'], $allowedCiphers)) {
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if (in_array($options['@CipherOptions']['Cipher'], AbstractCryptoClient::$supportedCiphers)) {
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throw $v1SchemaException;
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}
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throw new CryptoException("The requested object is encrypted with"
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. " the cipher '{$options['@CipherOptions']['Cipher']}', which is not"
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. " supported for decryption with the selected security profile."
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. " This profile allows decryption with: "
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. implode(", ", $allowedCiphers));
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}
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if (!in_array(
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$envelope[MetadataEnvelope::KEY_WRAP_ALGORITHM_HEADER],
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$allowedKeywraps
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)) {
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if (in_array(
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$envelope[MetadataEnvelope::KEY_WRAP_ALGORITHM_HEADER],
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AbstractCryptoClient::$supportedKeyWraps)
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) {
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throw $v1SchemaException;
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}
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throw new CryptoException("The requested object is encrypted with"
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. " the keywrap schema '{$envelope[MetadataEnvelope::KEY_WRAP_ALGORITHM_HEADER]}',"
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. " which is not supported for decryption with the current security"
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. " profile.");
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}
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$matdesc = json_decode(
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$envelope[MetadataEnvelope::MATERIALS_DESCRIPTION_HEADER],
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true
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);
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if (isset($matdesc['aws:x-amz-cek-alg'])
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&& $envelope[MetadataEnvelope::CONTENT_CRYPTO_SCHEME_HEADER] !==
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$matdesc['aws:x-amz-cek-alg']
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) {
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throw new CryptoException("There is a mismatch in specified content"
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. " encryption algrithm between the materials description value"
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. " and the metadata envelope value: {$matdesc['aws:x-amz-cek-alg']}"
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. " vs. {$envelope[MetadataEnvelope::CONTENT_CRYPTO_SCHEME_HEADER]}.");
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}
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}
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/**
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* Generates a stream that wraps the cipher text with the proper cipher and
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* uses the content encryption key (CEK) to decrypt the data when read.
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*
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* @param string $cipherText Plain-text data to be encrypted using the
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* materials, algorithm, and data provided.
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* @param string $cek A content encryption key for use by the stream for
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* encrypting the plaintext data.
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* @param array $cipherOptions Options for use in determining the cipher to
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* be used for encrypting data.
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*
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* @return AesStreamInterface
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*
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* @internal
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*/
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protected function getDecryptingStream(
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$cipherText,
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$cek,
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$cipherOptions
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) {
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$cipherTextStream = Psr7\Utils::streamFor($cipherText);
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switch ($cipherOptions['Cipher']) {
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case 'gcm':
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$cipherOptions['Tag'] = $this->getTagFromCiphertextStream(
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$cipherTextStream,
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$cipherOptions['TagLength']
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);
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return new AesGcmDecryptingStream(
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$this->getStrippedCiphertextStream(
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$cipherTextStream,
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$cipherOptions['TagLength']
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),
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$cek,
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$cipherOptions['Iv'],
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$cipherOptions['Tag'],
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$cipherOptions['Aad'] = isset($cipherOptions['Aad'])
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? $cipherOptions['Aad']
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: '',
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$cipherOptions['TagLength'] ?: null,
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$cipherOptions['KeySize']
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);
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default:
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$cipherMethod = $this->buildCipherMethod(
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$cipherOptions['Cipher'],
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$cipherOptions['Iv'],
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$cipherOptions['KeySize']
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);
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return new AesDecryptingStream(
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$cipherTextStream,
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$cek,
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$cipherMethod
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);
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}
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}
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}
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<?php
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namespace Aws\Crypto;
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use Aws\Exception\CryptoException;
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use GuzzleHttp\Psr7;
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use GuzzleHttp\Psr7\LimitStream;
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use Psr\Http\Message\StreamInterface;
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trait DecryptionTraitV2
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{
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/**
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* Dependency to reverse lookup the openssl_* cipher name from the AESName
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* in the MetadataEnvelope.
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*
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* @param $aesName
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*
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* @return string
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*
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* @internal
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*/
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abstract protected function getCipherFromAesName($aesName);
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/**
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* Dependency to generate a CipherMethod from a set of inputs for loading
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* in to an AesDecryptingStream.
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*
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* @param string $cipherName Name of the cipher to generate for decrypting.
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* @param string $iv Base Initialization Vector for the cipher.
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* @param int $keySize Size of the encryption key, in bits, that will be
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* used.
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*
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* @return Cipher\CipherMethod
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*
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* @internal
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*/
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abstract protected function buildCipherMethod($cipherName, $iv, $keySize);
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/**
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* Builds an AesStreamInterface using cipher options loaded from the
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* MetadataEnvelope and MaterialsProvider. Can decrypt data from both the
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* legacy and V2 encryption client workflows.
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*
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* @param string $cipherText Plain-text data to be encrypted using the
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* materials, algorithm, and data provided.
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* @param MaterialsProviderInterfaceV2 $provider A provider to supply and encrypt
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* materials used in encryption.
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* @param MetadataEnvelope $envelope A storage envelope for encryption
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* metadata to be read from.
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* @param array $options Options used for decryption.
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*
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* @return AesStreamInterface
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*
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* @throws \InvalidArgumentException Thrown when a value in $cipherOptions
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* is not valid.
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*
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* @internal
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*/
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public function decrypt(
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$cipherText,
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MaterialsProviderInterfaceV2 $provider,
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MetadataEnvelope $envelope,
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array $options = []
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)
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{
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$commitmentPolicy = $this->getKeyCommitmentPolicy($options);
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unset($options['@CommitmentPolicy']);
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if (isset($envelope[MetadataEnvelope::ENCRYPTED_DATA_KEY_V3])) {
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if ($commitmentPolicy !== "FORBID_ENCRYPT_ALLOW_DECRYPT") {
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throw new CryptoException(
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"The requested item is encrypted"
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. " with Key Commitment. The current policy {$commitmentPolicy}"
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. " conflicts with the object metadata. Select an appropriate"
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. " '@CommitmentPolicy' to decrypt this item."
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);
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}
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$algorithmSuite = AlgorithmSuite::ALG_AES_256_GCM_HKDF_SHA512_COMMIT_KEY;
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$options['@CipherOptions'] = $options['@CipherOptions'] ?? [];
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$options['@CipherOptions']['Iv'] = str_repeat("\1", 12);
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$options['@CipherOptions']['TagLength'] = $algorithmSuite->getCipherTagLengthInBytes();
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$materialDescription = json_decode(
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$envelope[MetadataEnvelope::ENCRYPTION_CONTEXT_V3],
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true
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);
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$cek = $provider->decryptCek(
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base64_decode($envelope[MetadataEnvelope::ENCRYPTED_DATA_KEY_V3]),
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$materialDescription,
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$options
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);
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$options['@CipherOptions']['KeySize'] = strlen($cek) * 8;
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$options['@CipherOptions']['Cipher'] = $this->getCipherFromAesName(
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$this->numericalContenCipherToAesName($envelope)
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);
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$this->validateOptionsAndEnvelope($options, $envelope);
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$messageId = base64_decode($envelope[MetadataEnvelope::MESSAGE_ID_V3]);
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$commitmentKey = base64_decode($envelope[MetadataEnvelope::KEY_COMMITMENT_V3]);
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if (strlen($messageId) !== ($algorithmSuite->getKeyCommitmentSaltLengthBits()) / 8) {
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throw new CryptoException("Invalid MessageId length found in object envelope.");
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}
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if (strlen($commitmentKey) !== $algorithmSuite->getCommitmentOutputKeyLengthBytes()) {
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throw new CryptoException("Invalid Commitment Key length found in object envelope.");
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}
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$decryptionStream = $this->getCommitingDecryptingStream(
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$cipherText,
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$cek,
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$options['@CipherOptions'],
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$messageId,
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$commitmentKey,
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$algorithmSuite
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);
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unset($cek);
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return $decryptionStream;
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} else {
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$options['@CipherOptions'] = $options['@CipherOptions'] ?? [];
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$options['@CipherOptions']['Iv'] = base64_decode(
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$envelope[MetadataEnvelope::IV_HEADER]
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);
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$options['@CipherOptions']['TagLength'] =
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$envelope[MetadataEnvelope::CRYPTO_TAG_LENGTH_HEADER] / 8;
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$cek = $provider->decryptCek(
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base64_decode(
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$envelope[MetadataEnvelope::CONTENT_KEY_V2_HEADER]
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),
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json_decode(
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$envelope[MetadataEnvelope::MATERIALS_DESCRIPTION_HEADER],
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true
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),
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$options
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);
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$options['@CipherOptions']['KeySize'] = strlen($cek) * 8;
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$options['@CipherOptions']['Cipher'] = $this->getCipherFromAesName(
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$envelope[MetadataEnvelope::CONTENT_CRYPTO_SCHEME_HEADER]
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);
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$this->validateOptionsAndEnvelope($options, $envelope);
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$decryptionStream = $this->getDecryptingStream(
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$cipherText,
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$cek,
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$options['@CipherOptions']
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);
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unset($cek);
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return $decryptionStream;
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}
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}
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private function buildMaterialDescription(
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MetadataEnvelope $envelope
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): array
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{
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switch ($envelope[MetadataEnvelope::ENCRYPTED_DATA_KEY_ALGORITHM_V3]) {
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case 12:
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return ['aws:x-amz-cek-alg' => '115'];
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default:
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throw new CryptoException(
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"Unknown Encrypted Data Key "
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. "wrapping algorithm found: "
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. "{$envelope[MetadataEnvelope::ENCRYPTED_DATA_KEY_ALGORITHM_V3]}"
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);
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}
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}
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private function numericalContenCipherToAesName(
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MetadataEnvelope $envelope
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): string
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{
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switch ($envelope[MetadataEnvelope::CONTENT_CIPHER_V3]) {
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case 115:
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return 'AES/GCM/NoPadding';
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default:
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throw new CryptoException(
|
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"Unknown Encrypted Data Key "
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. "wrapping algorithm found: "
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. "{$envelope[MetadataEnvelope::ENCRYPTED_DATA_KEY_ALGORITHM_V3]}"
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);
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}
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|
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}
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|
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private function getTagFromCiphertextStream(
|
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StreamInterface $cipherText,
|
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$tagLength
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)
|
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{
|
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$cipherTextSize = $cipherText->getSize();
|
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if ($cipherTextSize == null || $cipherTextSize <= 0) {
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throw new \RuntimeException('Cannot decrypt a stream of unknown'
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. ' size.');
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}
|
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return (string) new LimitStream(
|
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$cipherText,
|
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$tagLength,
|
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$cipherTextSize - $tagLength
|
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);
|
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}
|
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|
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private function getStrippedCiphertextStream(
|
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StreamInterface $cipherText,
|
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$tagLength
|
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)
|
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{
|
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$cipherTextSize = $cipherText->getSize();
|
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if ($cipherTextSize == null || $cipherTextSize <= 0) {
|
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throw new \RuntimeException('Cannot decrypt a stream of unknown'
|
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. ' size.');
|
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}
|
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return new LimitStream(
|
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$cipherText,
|
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$cipherTextSize - $tagLength,
|
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0
|
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);
|
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}
|
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|
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private function validateOptionsAndEnvelope($options, $envelope): void
|
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{
|
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$allowedCiphers = AbstractCryptoClientV2::$supportedCiphers;
|
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$allowedKeywraps = AbstractCryptoClientV2::$supportedKeyWraps;
|
||||
if ($options['@SecurityProfile'] == 'V2_AND_LEGACY') {
|
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$allowedCiphers = array_unique(array_merge(
|
||||
$allowedCiphers,
|
||||
AbstractCryptoClient::$supportedCiphers
|
||||
));
|
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$allowedKeywraps = array_unique(array_merge(
|
||||
$allowedKeywraps,
|
||||
AbstractCryptoClient::$supportedKeyWraps
|
||||
));
|
||||
}
|
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|
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$v1SchemaException = new CryptoException("The requested object is encrypted"
|
||||
. " with V1 encryption schemas that have been disabled by"
|
||||
. " client configuration @SecurityProfile=V2. Retry with"
|
||||
. " V2_AND_LEGACY enabled or reencrypt the object.");
|
||||
|
||||
if (!in_array($options['@CipherOptions']['Cipher'], $allowedCiphers)) {
|
||||
if (in_array($options['@CipherOptions']['Cipher'], AbstractCryptoClient::$supportedCiphers)) {
|
||||
throw $v1SchemaException;
|
||||
}
|
||||
throw new CryptoException("The requested object is encrypted with"
|
||||
. " the cipher '{$options['@CipherOptions']['Cipher']}', which is not"
|
||||
. " supported for decryption with the selected security profile."
|
||||
. " This profile allows decryption with: "
|
||||
. implode(", ", $allowedCiphers));
|
||||
}
|
||||
|
||||
if (isset($envelope[MetadataEnvelope::ENCRYPTED_DATA_KEY_V3])) {
|
||||
if ($envelope[MetadataEnvelope::ENCRYPTED_DATA_KEY_ALGORITHM_V3] !== '12') {
|
||||
throw new CryptoException("The requested object is encrypted with"
|
||||
. " the keywrap schema '{$envelope[MetadataEnvelope::ENCRYPTED_DATA_KEY_ALGORITHM_V3]}',"
|
||||
. " which is not supported for decryption with the current security"
|
||||
. " profile.");
|
||||
}
|
||||
} else {
|
||||
if (!in_array($envelope[MetadataEnvelope::KEY_WRAP_ALGORITHM_HEADER], $allowedKeywraps)) {
|
||||
if (in_array($envelope[MetadataEnvelope::KEY_WRAP_ALGORITHM_HEADER], AbstractCryptoClient::$supportedKeyWraps)) {
|
||||
throw $v1SchemaException;
|
||||
}
|
||||
|
||||
throw new CryptoException("The requested object is encrypted with"
|
||||
. " the keywrap schema '{$envelope[MetadataEnvelope::KEY_WRAP_ALGORITHM_HEADER]}',"
|
||||
. " which is not supported for decryption with the current security"
|
||||
. " profile.");
|
||||
}
|
||||
$matdesc = json_decode(
|
||||
$envelope[MetadataEnvelope::MATERIALS_DESCRIPTION_HEADER],
|
||||
true
|
||||
);
|
||||
if (isset($matdesc['aws:x-amz-cek-alg'])
|
||||
&& ($envelope[MetadataEnvelope::CONTENT_CRYPTO_SCHEME_HEADER]
|
||||
!== $matdesc['aws:x-amz-cek-alg'])
|
||||
) {
|
||||
throw new CryptoException("There is a mismatch in specified content"
|
||||
. " encryption algrithm between the materials description value"
|
||||
. " and the metadata envelope value: {$matdesc['aws:x-amz-cek-alg']}"
|
||||
. " vs. {$envelope[MetadataEnvelope::CONTENT_CRYPTO_SCHEME_HEADER]}.");
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Generates a stream that wraps the cipher text with the proper cipher and
|
||||
* uses the content encryption key (CEK) to decrypt the data when read.
|
||||
*
|
||||
* @param string $cipherText Plain-text data to be encrypted using the
|
||||
* materials, algorithm, and data provided.
|
||||
* @param string $cek A content encryption key for use by the stream for
|
||||
* encrypting the plaintext data.
|
||||
* @param array $cipherOptions Options for use in determining the cipher to
|
||||
* be used for encrypting data.
|
||||
*
|
||||
* @return AesStreamInterface
|
||||
*
|
||||
* @internal
|
||||
*/
|
||||
protected function getDecryptingStream(
|
||||
$cipherText,
|
||||
$cek,
|
||||
$cipherOptions
|
||||
)
|
||||
{
|
||||
$cipherTextStream = Psr7\Utils::streamFor($cipherText);
|
||||
switch ($cipherOptions['Cipher']) {
|
||||
case 'gcm':
|
||||
$cipherOptions['Tag'] = $this->getTagFromCiphertextStream(
|
||||
$cipherTextStream,
|
||||
$cipherOptions['TagLength']
|
||||
);
|
||||
|
||||
return new AesGcmDecryptingStream(
|
||||
$this->getStrippedCiphertextStream(
|
||||
$cipherTextStream,
|
||||
$cipherOptions['TagLength']
|
||||
),
|
||||
$cek,
|
||||
$cipherOptions['Iv'],
|
||||
$cipherOptions['Tag'],
|
||||
$cipherOptions['Aad'] = $cipherOptions['Aad'] ?? '',
|
||||
$cipherOptions['TagLength'] ?: null,
|
||||
$cipherOptions['KeySize']
|
||||
);
|
||||
default:
|
||||
$cipherMethod = $this->buildCipherMethod(
|
||||
$cipherOptions['Cipher'],
|
||||
$cipherOptions['Iv'],
|
||||
$cipherOptions['KeySize']
|
||||
);
|
||||
return new AesDecryptingStream(
|
||||
$cipherTextStream,
|
||||
$cek,
|
||||
$cipherMethod
|
||||
);
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Generates a stream that wraps the cipher text with the proper cipher and
|
||||
* uses the content encryption key (CEK) to derive both a derived content encryption key
|
||||
* and a commitment key to decrypt the data when read.
|
||||
*
|
||||
* @param string $cipherText Plain-text data to be encrypted using the
|
||||
* materials, algorithm, and data provided.
|
||||
* @param string $cek A content encryption key for use by the stream for
|
||||
* encrypting the plaintext data.
|
||||
* @param array $cipherOptions Options for use in determining the cipher to
|
||||
* be used for encrypting data.
|
||||
* @param string $messageId a string value used to calculate both a commitment
|
||||
* key and derived content encryption key
|
||||
* @param string $commitmentKey a string value to compare with the calculated commitment
|
||||
* key value, if the values don't match an exception is raised.
|
||||
*
|
||||
* @return AesStreamInterface | CryptoException
|
||||
*
|
||||
* @internal
|
||||
*/
|
||||
protected function getCommitingDecryptingStream(
|
||||
string $cipherText,
|
||||
string $cek,
|
||||
array $cipherOptions,
|
||||
string $messageId,
|
||||
string $commitmentKey,
|
||||
AlgorithmSuite $algorithmSuite
|
||||
): AesStreamInterface|CryptoException
|
||||
{
|
||||
$algorithmSuiteIdAsBytes = pack('n', $algorithmSuite->getId());
|
||||
$derivedEncryptionKeyInfo = $algorithmSuiteIdAsBytes . "DERIVEKEY";
|
||||
$commitmentKeyInfo = $algorithmSuiteIdAsBytes . "COMMITKEY";
|
||||
$derivedEncryptionKey = hash_hkdf(
|
||||
$algorithmSuite->getHashingAlgorithm(),
|
||||
$cek,
|
||||
$algorithmSuite->getDerivationOutputKeyLengthBytes(),
|
||||
$derivedEncryptionKeyInfo,
|
||||
$messageId
|
||||
);
|
||||
$calculatedCommitmentKey = hash_hkdf(
|
||||
$algorithmSuite->getHashingAlgorithm(),
|
||||
$cek,
|
||||
$algorithmSuite->getCommitmentOutputKeyLengthBytes(),
|
||||
$commitmentKeyInfo,
|
||||
$messageId
|
||||
);
|
||||
|
||||
if ($commitmentKey != $calculatedCommitmentKey) {
|
||||
throw new CryptoException("Calculated commitment key does "
|
||||
. "not match expected commitment key value ");
|
||||
}
|
||||
|
||||
$cipherTextStream = Psr7\Utils::streamFor($cipherText);
|
||||
switch ($cipherOptions['Cipher']) {
|
||||
case 'gcm':
|
||||
$cipherOptions['Tag'] = $this->getTagFromCiphertextStream(
|
||||
$cipherTextStream,
|
||||
$cipherOptions['TagLength']
|
||||
);
|
||||
$cipherOptions['Aad'] = isset($cipherOptions['Aad'])
|
||||
? $cipherOptions['Aad'] + $algorithmSuiteIdAsBytes
|
||||
: $algorithmSuiteIdAsBytes;
|
||||
|
||||
return new AesGcmDecryptingStream(
|
||||
$this->getStrippedCiphertextStream(
|
||||
$cipherTextStream,
|
||||
$cipherOptions['TagLength']
|
||||
),
|
||||
$derivedEncryptionKey,
|
||||
$cipherOptions['Iv'],
|
||||
$cipherOptions['Tag'],
|
||||
$cipherOptions['Aad'],
|
||||
$cipherOptions['TagLength'] ?: null,
|
||||
$cipherOptions['KeySize']
|
||||
);
|
||||
default:
|
||||
throw new CryptoException("Unsupported Cipher used for key commitment messages."
|
||||
. " Found {$cipherOptions["Cipher"]}. Only 'gcm' is supported.");
|
||||
}
|
||||
}
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in a new issue