spaces.php

This commit is contained in:
Devang Srivastava 2017-12-07 21:23:18 +05:30
commit eefa32741e
845 changed files with 50409 additions and 0 deletions

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<?php
namespace Aws\Crypto;
use Aws\Crypto\Cipher\CipherMethod;
use Aws\Crypto\Cipher\Cbc;
use GuzzleHttp\Psr7\Stream;
/**
* @internal
*/
abstract class AbstractCryptoClient
{
private static $supportedCiphers = ['cbc', 'gcm'];
/**
* Returns if the passed cipher name is supported for encryption by the SDK.
*
* @param string $cipherName The name of a cipher to verify is registered.
*
* @return bool If the cipher passed is in our supported list.
*/
public static function isSupportedCipher($cipherName)
{
return in_array($cipherName, self::$supportedCiphers);
}
/**
* Returns an identifier recognizable by `openssl_*` functions, such as
* `aes-256-cbc` or `aes-128-ctr`.
*
* @param string $cipherName Name of the cipher being used for encrypting
* or decrypting.
* @param int $keySize Size of the encryption key, in bits, that will be
* used.
*
* @return string
*/
protected function getCipherOpenSslName($cipherName, $keySize)
{
return "aes-{$keySize}-{$cipherName}";
}
/**
* Constructs a CipherMethod for the given name, initialized with the other
* data passed for use in encrypting or decrypting.
*
* @param string $cipherName Name of the cipher to generate for encrypting.
* @param string $iv Base Initialization Vector for the cipher.
* @param int $keySize Size of the encryption key, in bits, that will be
* used.
*
* @return CipherMethod
*
* @internal
*/
protected function buildCipherMethod($cipherName, $iv, $keySize)
{
switch ($cipherName) {
case 'cbc':
return new Cbc(
$iv,
$keySize
);
default:
return null;
}
}
/**
* Performs a reverse lookup to get the openssl_* cipher name from the
* AESName passed in from the MetadataEnvelope.
*
* @param $aesName
*
* @return string
*
* @internal
*/
protected function getCipherFromAesName($aesName)
{
switch ($aesName) {
case 'AES/GCM/NoPadding':
return 'gcm';
case 'AES/CBC/PKCS5Padding':
return 'cbc';
default:
throw new \RuntimeException('Unrecognized or unsupported'
. ' AESName for reverse lookup.');
}
}
/**
* Dependency to provide an interface for building an encryption stream for
* data given cipher details, metadata, and materials to do so.
*
* @param Stream $plaintext Plain-text data to be encrypted using the
* materials, algorithm, and data provided.
* @param array $cipherOptions Options for use in determining the cipher to
* be used for encrypting data.
* @param MaterialsProvider $provider A provider to supply and encrypt
* materials used in encryption.
* @param MetadataEnvelope $envelope A storage envelope for encryption
* metadata to be added to.
*
* @return AesStreamInterface
*
* @internal
*/
abstract public function encrypt(
Stream $plaintext,
array $cipherOptions,
MaterialsProvider $provider,
MetadataEnvelope $envelope
);
/**
* Dependency to provide an interface for building a decryption stream for
* cipher text given metadata and materials to do so.
*
* @param string $cipherText Plain-text data to be decrypted using the
* materials, algorithm, and data provided.
* @param MaterialsProvider $provider A provider to supply and encrypt
* materials used in encryption.
* @param MetadataEnvelope $envelope A storage envelope for encryption
* metadata to be read from.
* @param array $cipherOptions Additional verification options.
*
* @return AesStreamInterface
*
* @internal
*/
abstract public function decrypt(
$cipherText,
MaterialsProvider $provider,
MetadataEnvelope $envelope,
array $cipherOptions = []
);
}

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<?php
namespace Aws\Crypto;
use GuzzleHttp\Psr7\StreamDecoratorTrait;
use \LogicException;
use Psr\Http\Message\StreamInterface;
use Aws\Crypto\Cipher\CipherMethod;
/**
* @internal Represents a stream of data to be decrypted with passed cipher.
*/
class AesDecryptingStream implements AesStreamInterface
{
const BLOCK_SIZE = 16; // 128 bits
use StreamDecoratorTrait;
/**
* @var string
*/
private $buffer = '';
/**
* @var CipherMethod
*/
private $cipherMethod;
/**
* @var string
*/
private $key;
/**
* @var StreamInterface
*/
private $stream;
/**
* @param StreamInterface $cipherText
* @param string $key
* @param CipherMethod $cipherMethod
*/
public function __construct(
StreamInterface $cipherText,
$key,
CipherMethod $cipherMethod
) {
$this->stream = $cipherText;
$this->key = $key;
$this->cipherMethod = clone $cipherMethod;
}
public function getOpenSslName()
{
return $this->cipherMethod->getOpenSslName();
}
public function getAesName()
{
return $this->cipherMethod->getAesName();
}
public function getCurrentIv()
{
return $this->cipherMethod->getCurrentIv();
}
public function getSize()
{
$plainTextSize = $this->stream->getSize();
if ($this->cipherMethod->requiresPadding()) {
// PKCS7 padding requires that between 1 and self::BLOCK_SIZE be
// added to the plaintext to make it an even number of blocks. The
// plaintext is between strlen($cipherText) - self::BLOCK_SIZE and
// strlen($cipherText) - 1
return null;
}
return $plainTextSize;
}
public function isWritable()
{
return false;
}
public function read($length)
{
if ($length > strlen($this->buffer)) {
$this->buffer .= $this->decryptBlock(
self::BLOCK_SIZE * ceil(($length - strlen($this->buffer)) / self::BLOCK_SIZE)
);
}
$data = substr($this->buffer, 0, $length);
$this->buffer = substr($this->buffer, $length);
return $data ? $data : '';
}
public function seek($offset, $whence = SEEK_SET)
{
if ($offset === 0 && $whence === SEEK_SET) {
$this->buffer = '';
$this->cipherMethod->seek(0, SEEK_SET);
$this->stream->seek(0, SEEK_SET);
} else {
throw new LogicException('AES encryption streams only support being'
. ' rewound, not arbitrary seeking.');
}
}
private function decryptBlock($length)
{
if ($this->stream->eof()) {
return '';
}
$cipherText = '';
do {
$cipherText .= $this->stream->read($length - strlen($cipherText));
} while (strlen($cipherText) < $length && !$this->stream->eof());
$options = OPENSSL_RAW_DATA;
if (!$this->stream->eof()
&& $this->stream->getSize() !== $this->stream->tell()
) {
$options |= OPENSSL_ZERO_PADDING;
}
$plaintext = openssl_decrypt(
$cipherText,
$this->cipherMethod->getOpenSslName(),
$this->key,
$options,
$this->cipherMethod->getCurrentIv()
);
$this->cipherMethod->update($cipherText);
return $plaintext;
}
}

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<?php
namespace Aws\Crypto;
use GuzzleHttp\Psr7\StreamDecoratorTrait;
use \LogicException;
use Psr\Http\Message\StreamInterface;
use Aws\Crypto\Cipher\CipherMethod;
/**
* @internal Represents a stream of data to be encrypted with a passed cipher.
*/
class AesEncryptingStream implements AesStreamInterface
{
const BLOCK_SIZE = 16; // 128 bits
use StreamDecoratorTrait;
/**
* @var string
*/
private $buffer = '';
/**
* @var CipherMethod
*/
private $cipherMethod;
/**
* @var string
*/
private $key;
/**
* @var StreamInterface
*/
private $stream;
/**
* @param StreamInterface $plainText
* @param string $key
* @param CipherMethod $cipherMethod
*/
public function __construct(
StreamInterface $plainText,
$key,
CipherMethod $cipherMethod
) {
$this->stream = $plainText;
$this->key = $key;
$this->cipherMethod = clone $cipherMethod;
}
public function getOpenSslName()
{
return $this->cipherMethod->getOpenSslName();
}
public function getAesName()
{
return $this->cipherMethod->getAesName();
}
public function getCurrentIv()
{
return $this->cipherMethod->getCurrentIv();
}
public function getSize()
{
$plainTextSize = $this->stream->getSize();
if ($this->cipherMethod->requiresPadding() && $plainTextSize !== null) {
// PKCS7 padding requires that between 1 and self::BLOCK_SIZE be
// added to the plaintext to make it an even number of blocks.
$padding = self::BLOCK_SIZE - $plainTextSize % self::BLOCK_SIZE;
return $plainTextSize + $padding;
}
return $plainTextSize;
}
public function isWritable()
{
return false;
}
public function read($length)
{
if ($length > strlen($this->buffer)) {
$this->buffer .= $this->encryptBlock(
self::BLOCK_SIZE * ceil(($length - strlen($this->buffer)) / self::BLOCK_SIZE)
);
}
$data = substr($this->buffer, 0, $length);
$this->buffer = substr($this->buffer, $length);
return $data ? $data : '';
}
public function seek($offset, $whence = SEEK_SET)
{
if ($whence === SEEK_CUR) {
$offset = $this->tell() + $offset;
$whence = SEEK_SET;
}
if ($whence === SEEK_SET) {
$this->buffer = '';
$wholeBlockOffset
= (int) ($offset / self::BLOCK_SIZE) * self::BLOCK_SIZE;
$this->stream->seek($wholeBlockOffset);
$this->cipherMethod->seek($wholeBlockOffset);
$this->read($offset - $wholeBlockOffset);
} else {
throw new LogicException('Unrecognized whence.');
}
}
private function encryptBlock($length)
{
if ($this->stream->eof()) {
return '';
}
$plainText = '';
do {
$plainText .= $this->stream->read($length - strlen($plainText));
} while (strlen($plainText) < $length && !$this->stream->eof());
$options = OPENSSL_RAW_DATA;
if (!$this->stream->eof()
|| $this->stream->getSize() !== $this->stream->tell()
) {
$options |= OPENSSL_ZERO_PADDING;
}
$cipherText = openssl_encrypt(
$plainText,
$this->cipherMethod->getOpenSslName(),
$this->key,
$options,
$this->cipherMethod->getCurrentIv()
);
$this->cipherMethod->update($cipherText);
return $cipherText;
}
}

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<?php
namespace Aws\Crypto;
use GuzzleHttp\Psr7;
use GuzzleHttp\Psr7\StreamDecoratorTrait;
use Psr\Http\Message\StreamInterface;
use GuzzleHttp\Psr7\LimitStream;
use \RuntimeException;
/**
* @internal Represents a stream of data to be gcm decrypted.
*/
class AesGcmDecryptingStream implements AesStreamInterface
{
use StreamDecoratorTrait;
private $aad;
private $initializationVector;
private $key;
private $keySize;
private $cipherText;
private $tag;
private $tagLength;
/**
* @param StreamInterface $cipherText
* @param string $key
* @param string $initializationVector
* @param string $tag
* @param string $aad
* @param int $tagLength
* @param int $keySize
*/
public function __construct(
StreamInterface $cipherText,
$key,
$initializationVector,
$tag,
$aad = '',
$tagLength = 128,
$keySize = 256
) {
if (version_compare(PHP_VERSION, '7.1', '<')) {
throw new RuntimeException(
'AES-GCM decryption is only supported in PHP 7.1 or greater'
);
}
$this->cipherText = $cipherText;
$this->key = $key;
$this->initializationVector = $initializationVector;
$this->tag = $tag;
$this->aad = $aad;
$this->tagLength = $tagLength;
$this->keySize = $keySize;
}
public function getOpenSslName()
{
return "aes-{$this->keySize}-gcm";
}
public function getAesName()
{
return 'AES/GCM/NoPadding';
}
public function getCurrentIv()
{
return $this->initializationVector;
}
public function createStream()
{
return Psr7\stream_for(openssl_decrypt(
(string) $this->cipherText,
$this->getOpenSslName(),
$this->key,
OPENSSL_RAW_DATA,
$this->initializationVector,
$this->tag,
$this->aad
));
}
public function isWritable()
{
return false;
}
}

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<?php
namespace Aws\Crypto;
use GuzzleHttp\Psr7;
use GuzzleHttp\Psr7\StreamDecoratorTrait;
use Psr\Http\Message\StreamInterface;
use \RuntimeException;
/**
* @internal Represents a stream of data to be gcm encrypted.
*/
class AesGcmEncryptingStream implements AesStreamInterface
{
use StreamDecoratorTrait;
private $aad;
private $initializationVector;
private $key;
private $keySize;
private $plaintext;
private $tag = '';
private $tagLength;
/**
* @param StreamInterface $plaintext
* @param string $key
* @param string $initializationVector
* @param string $aad
* @param int $tagLength
* @param int $keySize
*/
public function __construct(
StreamInterface $plaintext,
$key,
$initializationVector,
$aad = '',
$tagLength = 16,
$keySize = 256
) {
if (version_compare(PHP_VERSION, '7.1', '<')) {
throw new RuntimeException(
'AES-GCM decryption is only supported in PHP 7.1 or greater'
);
}
$this->plaintext = $plaintext;
$this->key = $key;
$this->initializationVector = $initializationVector;
$this->aad = $aad;
$this->tagLength = $tagLength;
$this->keySize = $keySize;
}
public function getOpenSslName()
{
return "aes-{$this->keySize}-gcm";
}
public function getAesName()
{
return 'AES/GCM/NoPadding';
}
public function getCurrentIv()
{
return $this->initializationVector;
}
public function createStream()
{
return Psr7\stream_for(openssl_encrypt(
(string) $this->plaintext,
$this->getOpenSslName(),
$this->key,
OPENSSL_RAW_DATA,
$this->initializationVector,
$this->tag,
$this->aad,
$this->tagLength
));
}
/**
* @return string
*/
public function getTag()
{
return $this->tag;
}
public function isWritable()
{
return false;
}
}

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<?php
namespace Aws\Crypto;
use Psr\Http\Message\StreamInterface;
interface AesStreamInterface extends StreamInterface
{
/**
* Returns an identifier recognizable by `openssl_*` functions, such as
* `aes-256-cbc` or `aes-128-ctr`.
*
* @return string
*/
public function getOpenSslName();
/**
* Returns an AES recognizable name, such as 'AES/GCM/NoPadding'.
*
* @return string
*/
public function getAesName();
/**
* Returns the IV that should be used to initialize the next block in
* encrypt or decrypt.
*
* @return string
*/
public function getCurrentIv();
}

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<?php
namespace Aws\Crypto\Cipher;
use \InvalidArgumentException;
use \LogicException;
/**
* An implementation of the CBC cipher for use with an AesEncryptingStream or
* AesDecrypting stream.
*/
class Cbc implements CipherMethod
{
const BLOCK_SIZE = 16;
/**
* @var string
*/
private $baseIv;
/**
* @var string
*/
private $iv;
/**
* @var int
*/
private $keySize;
/**
* @param string $iv Base Initialization Vector for the cipher.
* @param int $keySize Size of the encryption key, in bits, that will be
* used.
*
* @throws InvalidArgumentException Thrown if the passed iv does not match
* the iv length required by the cipher.
*/
public function __construct($iv, $keySize = 256)
{
$this->baseIv = $this->iv = $iv;
$this->keySize = $keySize;
if (strlen($iv) !== openssl_cipher_iv_length($this->getOpenSslName())) {
throw new InvalidArgumentException('Invalid initialization vector');
}
}
public function getOpenSslName()
{
return "aes-{$this->keySize}-cbc";
}
public function getAesName()
{
return 'AES/CBC/PKCS5Padding';
}
public function getCurrentIv()
{
return $this->iv;
}
public function requiresPadding()
{
return true;
}
public function seek($offset, $whence = SEEK_SET)
{
if ($offset === 0 && $whence === SEEK_SET) {
$this->iv = $this->baseIv;
} else {
throw new LogicException('CBC initialization only support being'
. ' rewound, not arbitrary seeking.');
}
}
public function update($cipherTextBlock)
{
$this->iv = substr($cipherTextBlock, self::BLOCK_SIZE * -1);
}
}

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<?php
namespace Aws\Crypto\Cipher;
interface CipherMethod
{
/**
* Returns an identifier recognizable by `openssl_*` functions, such as
* `aes-256-cbc` or `aes-128-ctr`.
*
* @return string
*/
public function getOpenSslName();
/**
* Returns an AES recognizable name, such as 'AES/GCM/NoPadding'.
*
* @return string
*/
public function getAesName();
/**
* Returns the IV that should be used to initialize the next block in
* encrypt or decrypt.
*
* @return string
*/
public function getCurrentIv();
/**
* Indicates whether the cipher method used with this IV requires padding
* the final block to make sure the plaintext is evenly divisible by the
* block size.
*
* @return boolean
*/
public function requiresPadding();
/**
* Adjust the return of this::getCurrentIv to reflect a seek performed on
* the encryption stream using this IV object.
*
* @param int $offset
* @param int $whence
*
* @throws LogicException Thrown if the requested seek is not supported by
* this IV implementation. For example, a CBC IV
* only supports a full rewind ($offset === 0 &&
* $whence === SEEK_SET)
*/
public function seek($offset, $whence = SEEK_SET);
/**
* Take account of the last cipher text block to adjust the return of
* this::getCurrentIv
*
* @param string $cipherTextBlock
*/
public function update($cipherTextBlock);
}

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<?php
namespace Aws\Crypto;
use GuzzleHttp\Psr7;
use GuzzleHttp\Psr7\LimitStream;
trait DecryptionTrait
{
/**
* Dependency to reverse lookup the openssl_* cipher name from the AESName
* in the MetadataEnvelope.
*
* @param $aesName
*
* @return string
*
* @internal
*/
abstract protected function getCipherFromAesName($aesName);
/**
* Dependency to generate a CipherMethod from a set of inputs for loading
* in to an AesDecryptingStream.
*
* @param string $cipherName Name of the cipher to generate for decrypting.
* @param string $iv Base Initialization Vector for the cipher.
* @param int $keySize Size of the encryption key, in bits, that will be
* used.
*
* @return Cipher\CipherMethod
*
* @internal
*/
abstract protected function buildCipherMethod($cipherName, $iv, $keySize);
/**
* Builds an AesStreamInterface using cipher options loaded from the
* MetadataEnvelope and MaterialsProvider.
*
* @param string $cipherText Plain-text data to be encrypted using the
* materials, algorithm, and data provided.
* @param MaterialsProvider $provider A provider to supply and encrypt
* materials used in encryption.
* @param MetadataEnvelope $envelope A storage envelope for encryption
* metadata to be read from.
* @param array $cipherOptions Additional verification options.
*
* @return AesStreamInterface
*
* @throws \InvalidArgumentException Thrown when a value in $cipherOptions
* is not valid.
*
* @internal
*/
protected function decrypt(
$cipherText,
MaterialsProvider $provider,
MetadataEnvelope $envelope,
array $cipherOptions = []
) {
$cipherOptions['Iv'] = base64_decode(
$envelope[MetadataEnvelope::IV_HEADER]
);
$cipherOptions['TagLength'] =
$envelope[MetadataEnvelope::CRYPTO_TAG_LENGTH_HEADER] / 8;
$cek = $provider->decryptCek(
base64_decode(
$envelope[MetadataEnvelope::CONTENT_KEY_V2_HEADER]
),
json_decode(
$envelope[MetadataEnvelope::MATERIALS_DESCRIPTION_HEADER],
true
)
);
$cipherOptions['KeySize'] = strlen($cek) * 8;
$cipherOptions['Cipher'] = $this->getCipherFromAesName(
$envelope[MetadataEnvelope::CONTENT_CRYPTO_SCHEME_HEADER]
);
$decryptionSteam = $this->getDecryptingStream(
$cipherText,
$cek,
$cipherOptions
);
unset($cek);
return $decryptionSteam;
}
private function getTagFromCiphertextStream(
Psr7\Stream $cipherText,
$tagLength
) {
$cipherTextSize = $cipherText->getSize();
if ($cipherTextSize == null || $cipherTextSize <= 0) {
throw new \RuntimeException('Cannot decrypt a stream of unknown'
. ' size.');
}
return (string) new LimitStream(
$cipherText,
$tagLength,
$cipherTextSize - $tagLength
);
}
private function getStrippedCiphertextStream(
Psr7\Stream $cipherText,
$tagLength
) {
$cipherTextSize = $cipherText->getSize();
if ($cipherTextSize == null || $cipherTextSize <= 0) {
throw new \RuntimeException('Cannot decrypt a stream of unknown'
. ' size.');
}
return new LimitStream(
$cipherText,
$cipherTextSize - $tagLength,
0
);
}
/**
* 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
) {
$cipherTextStream = Psr7\stream_for($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'],
$cipherOptions['Aad'] = isset($cipherOptions['Aad'])
? $cipherOptions['Aad']
: null,
$cipherOptions['TagLength'] ?: null,
$cipherOptions['KeySize']
);
default:
$cipherMethod = $this->buildCipherMethod(
$cipherOptions['Cipher'],
$cipherOptions['Iv'],
$cipherOptions['KeySize']
);
return new AesDecryptingStream(
$cipherTextStream,
$cek,
$cipherMethod
);
}
}
}

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<?php
namespace Aws\Crypto;
use GuzzleHttp\Psr7;
use GuzzleHttp\Psr7\AppendStream;
use GuzzleHttp\Psr7\Stream;
trait EncryptionTrait
{
private static $allowedOptions = [
'Cipher' => true,
'KeySize' => true,
'Aad' => true,
];
/**
* Dependency to generate a CipherMethod from a set of inputs for loading
* in to an AesEncryptingStream.
*
* @param string $cipherName Name of the cipher to generate for encrypting.
* @param string $iv Base Initialization Vector for the cipher.
* @param int $keySize Size of the encryption key, in bits, that will be
* used.
*
* @return Cipher\CipherMethod
*
* @internal
*/
abstract protected function buildCipherMethod($cipherName, $iv, $keySize);
/**
* Builds an AesStreamInterface and populates encryption metadata into the
* supplied envelope.
*
* @param Stream $plaintext Plain-text data to be encrypted using the
* materials, algorithm, and data provided.
* @param array $cipherOptions Options for use in determining the cipher to
* be used for encrypting data.
* @param MaterialsProvider $provider A provider to supply and encrypt
* materials used in encryption.
* @param MetadataEnvelope $envelope A storage envelope for encryption
* metadata to be added to.
*
* @return AesStreamInterface
*
* @throws \InvalidArgumentException Thrown when a value in $cipherOptions
* is not valid.
*
* @internal
*/
protected function encrypt(
Stream $plaintext,
array $cipherOptions,
MaterialsProvider $provider,
MetadataEnvelope $envelope
) {
$materialsDescription = $provider->getMaterialsDescription();
$cipherOptions = array_intersect_key(
$cipherOptions,
self::$allowedOptions
);
if (empty($cipherOptions['Cipher'])) {
throw new \InvalidArgumentException('An encryption cipher must be'
. ' specified in the "cipher_options".');
} elseif (!self::isSupportedCipher($cipherOptions['Cipher'])) {
throw new \InvalidArgumentException('The cipher requested is not'
. ' supported by the SDK.');
}
if (empty($cipherOptions['KeySize'])) {
$cipherOptions['KeySize'] = 256;
}
if (!is_int($cipherOptions['KeySize'])) {
throw new \InvalidArgumentException('The cipher "KeySize" must be'
. ' an integer.');
} elseif (!MaterialsProvider::isSupportedKeySize(
$cipherOptions['KeySize']
)) {
throw new \InvalidArgumentException('The cipher "KeySize" requested'
. ' is not supported by AES (128, 192, or 256).');
}
$cipherOptions['Iv'] = $provider->generateIv(
$this->getCipherOpenSslName(
$cipherOptions['Cipher'],
$cipherOptions['KeySize']
)
);
$cek = $provider->generateCek($cipherOptions['KeySize']);
list($encryptingStream, $aesName) = $this->getEncryptingStream(
$plaintext,
$cek,
$cipherOptions
);
// Populate envelope data
$envelope[MetadataEnvelope::CONTENT_KEY_V2_HEADER] =
$provider->encryptCek(
$cek,
$materialsDescription
);
unset($cek);
$envelope[MetadataEnvelope::IV_HEADER] =
base64_encode($cipherOptions['Iv']);
$envelope[MetadataEnvelope::KEY_WRAP_ALGORITHM_HEADER] =
$provider->getWrapAlgorithmName();
$envelope[MetadataEnvelope::CONTENT_CRYPTO_SCHEME_HEADER] = $aesName;
$envelope[MetadataEnvelope::UNENCRYPTED_CONTENT_LENGTH_HEADER] =
strlen($plaintext);
$envelope[MetadataEnvelope::UNENCRYPTED_CONTENT_MD5_HEADER] =
base64_encode(md5($plaintext));
$envelope[MetadataEnvelope::MATERIALS_DESCRIPTION_HEADER] =
json_encode($materialsDescription);
if (!empty($cipherOptions['Tag'])) {
$envelope[MetadataEnvelope::CRYPTO_TAG_LENGTH_HEADER] =
strlen($cipherOptions['Tag']) * 8;
}
return $encryptingStream;
}
/**
* Generates a stream that wraps the plaintext with the proper cipher and
* uses the content encryption key (CEK) to encrypt the data when read.
*
* @param Stream $plaintext 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, string]
*
* @internal
*/
protected function getEncryptingStream(
Stream $plaintext,
$cek,
&$cipherOptions
) {
switch ($cipherOptions['Cipher']) {
case 'gcm':
$cipherOptions['TagLength'] = 16;
$cipherTextStream = new AesGcmEncryptingStream(
$plaintext,
$cek,
$cipherOptions['Iv'],
$cipherOptions['Aad'] = isset($cipherOptions['Aad'])
? $cipherOptions['Aad']
: null,
$cipherOptions['TagLength'],
$cipherOptions['KeySize']
);
$appendStream = new AppendStream([
$cipherTextStream->createStream()
]);
$cipherOptions['Tag'] = $cipherTextStream->getTag();
$appendStream->addStream(Psr7\stream_for($cipherOptions['Tag']));
return [$appendStream, $cipherTextStream->getAesName()];
default:
$cipherMethod = $this->buildCipherMethod(
$cipherOptions['Cipher'],
$cipherOptions['Iv'],
$cipherOptions['KeySize']
);
$cipherTextStream = new AesEncryptingStream(
$plaintext,
$cek,
$cipherMethod
);
return [$cipherTextStream, $cipherTextStream->getAesName()];
}
}
}

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<?php
namespace Aws\Crypto;
use Aws\Kms\KmsClient;
/**
* Uses KMS to supply materials for encrypting and decrypting data.
*/
class KmsMaterialsProvider extends MaterialsProvider
{
private $kmsClient;
private $kmsKeyId;
/**
* @param KmsClient $kmsClient A KMS Client for use encrypting and
* decrypting keys.
* @param string $kmsKeyId The private KMS key id to be used for encrypting
* and decrypting keys.
*/
public function __construct(
KmsClient $kmsClient,
$kmsKeyId = null
) {
$this->kmsClient = $kmsClient;
$this->kmsKeyId = $kmsKeyId;
}
public function fromDecryptionEnvelope(MetadataEnvelope $envelope)
{
if (empty($envelope[MetadataEnvelope::MATERIALS_DESCRIPTION_HEADER])) {
throw new \RuntimeException('Not able to detect kms_cmk_id from an'
. ' empty materials description.');
}
$materialsDescription = json_decode(
$envelope[MetadataEnvelope::MATERIALS_DESCRIPTION_HEADER],
true
);
if (empty($materialsDescription['kms_cmk_id'])) {
throw new \RuntimeException('Not able to detect kms_cmk_id from kms'
. ' materials description.');
}
return new KmsMaterialsProvider(
$this->kmsClient,
$materialsDescription['kms_cmk_id']
);
}
/**
* The KMS key id for use in matching this Provider to its keys,
* consistently with other SDKs as 'kms_cmk_id'.
*
* @return array
*/
public function getMaterialsDescription()
{
return ['kms_cmk_id' => $this->kmsKeyId];
}
public function getWrapAlgorithmName()
{
return 'kms';
}
/**
* Takes a content encryption key (CEK) and description to return an encrypted
* key by using KMS' Encrypt API.
*
* @param string $unencryptedCek Key for use in encrypting other data
* that itself needs to be encrypted by the
* Provider.
* @param string $materialDescription Material Description for use in
* encrypting the $cek.
*
* @return string
*/
public function encryptCek($unencryptedCek, $materialDescription)
{
$encryptedDataKey = $this->kmsClient->encrypt([
'Plaintext' => $unencryptedCek,
'KeyId' => $this->kmsKeyId,
'EncryptionContext' => $materialDescription
]);
return base64_encode($encryptedDataKey['CiphertextBlob']);
}
/**
* Takes an encrypted content encryption key (CEK) and material description
* for use decrypting the key by using KMS' Decrypt API.
*
* @param string $encryptedCek Encrypted key to be decrypted by the Provider
* for use decrypting other data.
* @param string $materialDescription Material Description for use in
* encrypting the $cek.
*
* @return string
*/
public function decryptCek($encryptedCek, $materialDescription)
{
$result = $this->kmsClient->decrypt([
'CiphertextBlob' => $encryptedCek,
'EncryptionContext' => $materialDescription
]);
return $result['Plaintext'];
}
}

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<?php
namespace Aws\Crypto;
abstract class MaterialsProvider
{
private static $supportedKeySizes = [
128 => true,
192 => true,
256 => true,
];
/**
* Returns if the requested size is supported by AES.
*
* @param int $keySize Size of the requested key in bits.
*
* @return bool
*/
public static function isSupportedKeySize($keySize)
{
return isset(self::$supportedKeySizes[$keySize]);
}
/**
* Performs further initialization of the MaterialsProvider based on the
* data inside the MetadataEnvelope.
*
* @param MetadataEnvelope $envelope A storage envelope for encryption
* metadata to be read from.
*
* @return MaterialsProvider
*
* @throws \RuntimeException Thrown when there is an empty or improperly
* formed materials description in the envelope.
*
* @internal
*/
abstract public function fromDecryptionEnvelope(MetadataEnvelope $envelope);
/**
* Returns the material description for this Provider so it can be verified
* by encryption mechanisms.
*
* @return string
*/
abstract public function getMaterialsDescription();
/**
* Returns the wrap algorithm name for this Provider.
*
* @return string
*/
abstract public function getWrapAlgorithmName();
/**
* Takes a content encryption key (CEK) and description to return an
* encrypted key according to the Provider's specifications.
*
* @param string $unencryptedCek Key for use in encrypting other data
* that itself needs to be encrypted by the
* Provider.
* @param string $materialDescription Material Description for use in
* encrypting the $cek.
*
* @return string
*/
abstract public function encryptCek($unencryptedCek, $materialDescription);
/**
* Takes an encrypted content encryption key (CEK) and material description
* for use decrypting the key according to the Provider's specifications.
*
* @param string $encryptedCek Encrypted key to be decrypted by the Provider
* for use decrypting other data.
* @param string $materialDescription Material Description for use in
* encrypting the $cek.
*
* @return string
*/
abstract public function decryptCek($encryptedCek, $materialDescription);
/**
* @param string $keySize Length of a cipher key in bits for generating a
* random content encryption key (CEK).
*
* @return string
*/
public function generateCek($keySize)
{
return openssl_random_pseudo_bytes($keySize / 8);
}
/**
* @param string $openSslName Cipher OpenSSL name to use for generating
* an initialization vector.
*
* @return string
*/
public function generateIv($openSslName)
{
return openssl_random_pseudo_bytes(
openssl_cipher_iv_length($openSslName)
);
}
}

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<?php
namespace Aws\Crypto;
use Aws\HasDataTrait;
use \ArrayAccess;
use \IteratorAggregate;
use \InvalidArgumentException;
use \JsonSerializable;
/**
* Stores encryption metadata for reading and writing.
*
* @internal
*/
class MetadataEnvelope implements ArrayAccess, IteratorAggregate, JsonSerializable
{
use HasDataTrait;
const CONTENT_KEY_V2_HEADER = 'x-amz-key-v2';
const IV_HEADER = 'x-amz-iv';
const MATERIALS_DESCRIPTION_HEADER = 'x-amz-matdesc';
const KEY_WRAP_ALGORITHM_HEADER = 'x-amz-wrap-alg';
const CONTENT_CRYPTO_SCHEME_HEADER = 'x-amz-cek-alg';
const CRYPTO_TAG_LENGTH_HEADER = 'x-amz-tag-len';
const UNENCRYPTED_CONTENT_MD5_HEADER = 'x-amz-unencrypted-content-md5';
const UNENCRYPTED_CONTENT_LENGTH_HEADER = 'x-amz-unencrypted-content-length';
private static $constants = [];
public static function getConstantValues()
{
if (empty(self::$constants)) {
$reflection = new \ReflectionClass(static::class);
foreach (array_values($reflection->getConstants()) as $constant) {
self::$constants[$constant] = true;
}
}
return array_keys(self::$constants);
}
public function offsetSet($name, $value)
{
$constants = self::getConstantValues();
if (is_null($name) || !in_array($name, $constants)) {
throw new InvalidArgumentException('MetadataEnvelope fields must'
. ' must match a predefined offset; use the header constants.');
} else {
$this->data[$name] = $value;
}
}
public function jsonSerialize()
{
return $this->data;
}
}

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<?php
namespace Aws\Crypto;
interface MetadataStrategyInterface
{
/**
* Places the information in the MetadataEnvelope to the strategy specific
* location. Populates the PutObject arguments with any information
* necessary for loading.
*
* @param MetadataEnvelope $envelope Encryption data to save according to
* the strategy.
* @param array $args Starting arguments for PutObject.
*
* @return array Updated arguments for PutObject.
*/
public function save(MetadataEnvelope $envelope, array $args);
/**
* Generates a MetadataEnvelope according to the specific strategy using the
* passed arguments.
*
* @param array $args Arguments from Command and Result that contains
* S3 Object information, relevant headers, and command
* configuration.
*
* @return MetadataEnvelope
*/
public function load(array $args);
}