Spaces-API/aws/Aws/S3/Crypto/S3EncryptionClient.php
Devang Srivastava eefa32741e spaces.php
2017-12-07 21:23:18 +05:30

381 lines
15 KiB
PHP

<?php
namespace Aws\S3\Crypto;
use Aws\HashingStream;
use Aws\PhpHash;
use Aws\Crypto\AbstractCryptoClient;
use Aws\Crypto\EncryptionTrait;
use Aws\Crypto\DecryptionTrait;
use Aws\Crypto\MetadataEnvelope;
use Aws\Crypto\MaterialsProvider;
use Aws\Crypto\MetadataStrategyInterface;
use Aws\S3\S3Client;
use GuzzleHttp\Promise;
use GuzzleHttp\Promise\PromiseInterface;
use GuzzleHttp\Psr7;
/**
* Provides a wrapper for an S3Client that supplies functionality to encrypt
* data on putObject[Async] calls and decrypt data on getObject[Async] calls.
*/
class S3EncryptionClient extends AbstractCryptoClient
{
use EncryptionTrait, DecryptionTrait;
private $client;
private $instructionFileSuffix;
/**
* @param S3Client $client The S3Client to be used for true uploading and
* retrieving objects from S3 when using the
* encryption client.
* @param string|null $instructionFileSuffix Suffix for a client wide
* default when using instruction
* files for metadata storage.
*/
public function __construct(
S3Client $client,
$instructionFileSuffix = null
) {
$this->client = $client;
$this->instructionFileSuffix = $instructionFileSuffix;
}
private function getMaterialsProvider(array $args)
{
if ($args['@MaterialsProvider'] instanceof MaterialsProvider) {
return $args['@MaterialsProvider'];
} else {
throw new \InvalidArgumentException('An instance of MaterialsProvider'
. ' must be passed in the "MaterialsProvider" field.');
}
}
private function getInstructionFileSuffix(array $args)
{
return !empty($args['@InstructionFileSuffix'])
? $args['@InstructionFileSuffix']
: $this->instructionFileSuffix;
}
private static function getDefaultStrategy()
{
return new HeadersMetadataStrategy();
}
private function determineGetObjectStrategy(
$result,
$instructionFileSuffix
) {
if (isset($result['Metadata'][MetadataEnvelope::CONTENT_KEY_V2_HEADER])) {
return new HeadersMetadataStrategy();
} else {
return new InstructionFileMetadataStrategy(
$this->client,
$instructionFileSuffix
);
}
}
private function getMetadataStrategy(array $args, $instructionFileSuffix)
{
if (!empty($args['@MetadataStrategy'])) {
if ($args['@MetadataStrategy'] instanceof MetadataStrategyInterface) {
return $args['@MetadataStrategy'];
} elseif (is_string($args['@MetadataStrategy'])) {
switch ($args['@MetadataStrategy']) {
case HeadersMetadataStrategy::class:
return new HeadersMetadataStrategy();
case InstructionFileMetadataStrategy::class:
return new InstructionFileMetadataStrategy(
$this->client,
$instructionFileSuffix
);
default:
throw new \InvalidArgumentException('Could not match the'
. ' specified string in "MetadataStrategy" to a'
. ' predefined strategy.');
}
} else {
throw new \InvalidArgumentException('The metadata strategy that'
. ' was passed to "MetadataStrategy" was unrecognized.');
}
} elseif ($instructionFileSuffix) {
return new InstructionFileMetadataStrategy(
$this->client,
$instructionFileSuffix
);
}
return null;
}
/**
* Encrypts the data in the 'Body' field of $args and promises to upload it
* to the specified location on S3.
*
* @param array $args Arguments for encrypting an object and uploading it
* to S3 via PutObject.
*
* The required configuration arguments are as follows:
*
* - @MaterialsProvider: (MaterialsProvider) Provides Cek, Iv, and Cek
* encrypting/decrypting for encryption metadata.
* - @CipherOptions: (array) Cipher options for encrypting data. Only the
* Cipher option is required. Accepts the following:
* - Cipher: (string) cbc|gcm
* See also: AbstractCryptoClient::$supportedCiphers
* - KeySize: (int) 128|192|256
* See also: MaterialsProvider::$supportedKeySizes
* - Aad: (string) Additional authentication data. This option is
* passed directly to OpenSSL when using gcm. It is ignored when
* using cbc.
*
* The optional configuration arguments are as follows:
*
* - @MetadataStrategy: (MetadataStrategy|string|null) Strategy for storing
* MetadataEnvelope information. Defaults to using a
* HeadersMetadataStrategy. Can either be a class implementing
* MetadataStrategy, a class name of a predefined strategy, or empty/null
* to default.
* - @InstructionFileSuffix: (string|null) Suffix used when writing to an
* instruction file if using an InstructionFileMetadataHandler.
*
* @return PromiseInterface
*
* @throws \InvalidArgumentException Thrown when arguments above are not
* passed or are passed incorrectly.
*/
public function putObjectAsync(array $args)
{
$provider = $this->getMaterialsProvider($args);
unset($args['@MaterialsProvider']);
$instructionFileSuffix = $this->getInstructionFileSuffix($args);
unset($args['@InstructionFileSuffix']);
$strategy = $this->getMetadataStrategy($args, $instructionFileSuffix);
unset($args['@MetadataStrategy']);
$envelope = new MetadataEnvelope();
return Promise\promise_for($this->encrypt(
Psr7\stream_for($args['Body']),
$args['@CipherOptions'] ?: [],
$provider,
$envelope
))->then(
function ($encryptedBodyStream) use ($args) {
$hash = new PhpHash('sha256');
$hashingEncryptedBodyStream = new HashingStream(
$encryptedBodyStream,
$hash,
self::getContentShaDecorator($args)
);
return [$hashingEncryptedBodyStream, $args];
}
)->then(
function ($putObjectContents) use ($strategy, $envelope) {
list($bodyStream, $args) = $putObjectContents;
if ($strategy === null) {
$strategy = self::getDefaultStrategy();
}
$updatedArgs = $strategy->save($envelope, $args);
$updatedArgs['Body'] = $bodyStream;
return $updatedArgs;
}
)->then(
function ($args) {
unset($args['@CipherOptions']);
return $this->client->putObjectAsync($args);
}
);
}
private static function getContentShaDecorator(&$args)
{
return function ($hash) use (&$args) {
$args['ContentSHA256'] = bin2hex($hash);
};
}
/**
* Encrypts the data in the 'Body' field of $args and uploads it to the
* specified location on S3.
*
* @param array $args Arguments for encrypting an object and uploading it
* to S3 via PutObject.
*
* The required configuration arguments are as follows:
*
* - @MaterialsProvider: (MaterialsProvider) Provides Cek, Iv, and Cek
* encrypting/decrypting for encryption metadata.
* - @CipherOptions: (array) Cipher options for encrypting data. A Cipher
* is required. Accepts the following options:
* - Cipher: (string) cbc|gcm
* See also: AbstractCryptoClient::$supportedCiphers
* - KeySize: (int) 128|192|256
* See also: MaterialsProvider::$supportedKeySizes
* - Aad: (string) Additional authentication data. This option is
* passed directly to OpenSSL when using gcm. It is ignored when
* using cbc.
*
* The optional configuration arguments are as follows:
*
* - @MetadataStrategy: (MetadataStrategy|string|null) Strategy for storing
* MetadataEnvelope information. Defaults to using a
* HeadersMetadataStrategy. Can either be a class implementing
* MetadataStrategy, a class name of a predefined strategy, or empty/null
* to default.
* - @InstructionFileSuffix: (string|null) Suffix used when writing to an
* instruction file if an using an InstructionFileMetadataHandler was
* determined.
*
* @return \Aws\Result PutObject call result with the details of uploading
* the encrypted file.
*
* @throws \InvalidArgumentException Thrown when arguments above are not
* passed or are passed incorrectly.
*/
public function putObject(array $args)
{
return $this->putObjectAsync($args)->wait();
}
/**
* Promises to retrieve an object from S3 and decrypt the data in the
* 'Body' field.
*
* @param array $args Arguments for retrieving an object from S3 via
* GetObject and decrypting it.
*
* The required configuration argument is as follows:
*
* - @MaterialsProvider: (MaterialsProvider) Provides Cek, Iv, and Cek
* encrypting/decrypting for decryption metadata. May have data loaded
* from the MetadataEnvelope upon decryption.
*
* The optional configuration arguments are as follows:
*
* - SaveAs: (string) The path to a file on disk to save the decrypted
* object data. This will be handled by file_put_contents instead of the
* Guzzle sink.
*
* - @MetadataStrategy: (MetadataStrategy|string|null) Strategy for reading
* MetadataEnvelope information. Defaults to determining based on object
* response headers. Can either be a class implementing MetadataStrategy,
* a class name of a predefined strategy, or empty/null to default.
* - @InstructionFileSuffix: (string) Suffix used when looking for an
* instruction file if an InstructionFileMetadataHandler is being used.
* - @CipherOptions: (array) Cipher options for decrypting data. A Cipher
* is required. Accepts the following options:
* - Aad: (string) Additional authentication data. This option is
* passed directly to OpenSSL when using gcm. It is ignored when
* using cbc.
*
* @return PromiseInterface
*
* @throws \InvalidArgumentException Thrown when required arguments are not
* passed or are passed incorrectly.
*/
public function getObjectAsync(array $args)
{
$provider = $this->getMaterialsProvider($args);
unset($args['@MaterialsProvider']);
$instructionFileSuffix = $this->getInstructionFileSuffix($args);
unset($args['@InstructionFileSuffix']);
$strategy = $this->getMetadataStrategy($args, $instructionFileSuffix);
unset($args['@MetadataStrategy']);
$saveAs = null;
if (!empty($args['SaveAs'])) {
$saveAs = $args['SaveAs'];
}
$promise = $this->client->getObjectAsync($args)
->then(
function ($result) use (
$provider,
$instructionFileSuffix,
$strategy,
$args
) {
if ($strategy === null) {
$strategy = $this->determineGetObjectStrategy(
$result,
$instructionFileSuffix
);
}
$envelope = $strategy->load($args + [
'Metadata' => $result['Metadata']
]);
$provider = $provider->fromDecryptionEnvelope($envelope);
$result['Body'] = $this->decrypt(
$result['Body'],
$provider,
$envelope,
isset($args['@CipherOptions'])
? $args['@CipherOptions']
: []
);
return $result;
}
)->then(
function ($result) use ($saveAs) {
if (!empty($saveAs)) {
file_put_contents(
$saveAs,
(string)$result['Body'],
LOCK_EX
);
}
return $result;
}
);
return $promise;
}
/**
* Retrieves an object from S3 and decrypts the data in the 'Body' field.
*
* @param array $args Arguments for retrieving an object from S3 via
* GetObject and decrypting it.
*
* The required configuration argument is as follows:
*
* - @MaterialsProvider: (MaterialsProvider) Provides Cek, Iv, and Cek
* encrypting/decrypting for decryption metadata. May have data loaded
* from the MetadataEnvelope upon decryption.
*
* The optional configuration arguments are as follows:
*
* - SaveAs: (string) The path to a file on disk to save the decrypted
* object data. This will be handled by file_put_contents instead of the
* Guzzle sink.
* - @InstructionFileSuffix: (string|null) Suffix used when looking for an
* instruction file if an InstructionFileMetadataHandler was detected.
* - @CipherOptions: (array) Cipher options for encrypting data. A Cipher
* is required. Accepts the following options:
* - Aad: (string) Additional authentication data. This option is
* passed directly to OpenSSL when using gcm. It is ignored when
* using cbc.
*
* @return \Aws\Result GetObject call result with the 'Body' field
* wrapped in a decryption stream with its metadata
* information.
*
* @throws \InvalidArgumentException Thrown when arguments above are not
* passed or are passed incorrectly.
*/
public function getObject(array $args)
{
return $this->getObjectAsync($args)->wait();
}
}