Made dependencies of Kaymanager::setFileKey() explicit using dependency injection

This commit is contained in:
Sam Tuke 2012-08-01 14:11:41 +01:00
parent a7f3a67bc2
commit c4d1ad1b7d
3 changed files with 432 additions and 426 deletions

View File

@ -1,37 +1,37 @@
<?php
/**
* ownCloud
*
* @author Sam Tuke, Frank Karlitschek, Robin Appelman
* @copyright 2012 Sam Tuke samtuke@owncloud.com,
* Robin Appelman icewind@owncloud.com, Frank Karlitschek
* frank@owncloud.org
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
* License as published by the Free Software Foundation; either
* version 3 of the License, or any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU AFFERO GENERAL PUBLIC LICENSE for more details.
*
* You should have received a copy of the GNU Affero General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*
*/
namespace OCA_Encryption;
/**
* Class for common cryptography functionality
*/
class Crypt {
<?php
/**
* ownCloud
*
* @author Sam Tuke, Frank Karlitschek, Robin Appelman
* @copyright 2012 Sam Tuke samtuke@owncloud.com,
* Robin Appelman icewind@owncloud.com, Frank Karlitschek
* frank@owncloud.org
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
* License as published by the Free Software Foundation; either
* version 3 of the License, or any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU AFFERO GENERAL PUBLIC LICENSE for more details.
*
* You should have received a copy of the GNU Affero General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*
*/
namespace OCA_Encryption;
/**
* Class for common cryptography functionality
*/
class Crypt {
/**
* @brief return encryption mode client or server side encryption
* @brief return encryption mode client or server side encryption
* @param string user name (use system wide setting if name=null)
* @return string 'client' or 'server'
*/
@ -48,382 +48,382 @@ class Crypt {
}
return $mode;
}
/**
* @brief Create a new encryption keypair
* @return array publicKey, privatekey
*/
public static function createKeypair() {
$res = openssl_pkey_new();
// Get private key
openssl_pkey_export( $res, $privateKey );
// Get public key
$publicKey = openssl_pkey_get_details( $res );
$publicKey = $publicKey['key'];
return( array( 'publicKey' => $publicKey, 'privateKey' => $privateKey ) );
}
/**
* @brief Check if a file's contents contains an IV and is symmetrically encrypted
* @return true / false
*/
public static function isEncryptedContent( $content ) {
if ( !$content ) {
return false;
}
// Fetch encryption metadata from end of file
$meta = substr( $content, -22 );
// Fetch IV from end of file
$iv = substr( $meta, -16 );
// Fetch identifier from start of metadata
$identifier = substr( $meta, 0, 6 );
if ( $identifier == '00iv00') {
return true;
} else {
return false;
}
}
/**
* @brief Check if a file is encrypted via legacy system
* @return true / false
*/
public static function isLegacyEncryptedContent( $content, $path ) {
// Fetch all file metadata from DB
$metadata = \OC_FileCache_Cached::get( $content, '' );
// If a file is flagged with encryption in DB, but isn't a valid content + IV combination, it's probably using the legacy encryption system
if (
$content
and isset( $metadata['encrypted'] )
and $metadata['encrypted'] === true
and !self::isEncryptedContent( $content )
) {
return true;
} else {
return false;
}
}
/**
* @brief Symmetrically encrypt a string
* @returns encrypted file
*/
public static function encrypt( $plainContent, $iv, $passphrase = '' ) {
if ( $encryptedContent = openssl_encrypt( $plainContent, 'AES-128-CFB', $passphrase, false, $iv ) ) {
return $encryptedContent;
} else {
\OC_Log::write( 'Encryption library', 'Encryption (symmetric) of content failed' , \OC_Log::ERROR );
return false;
}
}
/**
* @brief Symmetrically decrypt a string
* @returns decrypted file
*/
public static function decrypt( $encryptedContent, $iv, $passphrase ) {
if ( $plainContent = openssl_decrypt( $encryptedContent, 'AES-128-CFB', $passphrase, false, $iv ) ) {
return $plainContent;
} else {
\OC_Log::write( 'Encryption library', 'Decryption (symmetric) of content failed' , \OC_Log::ERROR );
return false;
}
}
/**
* @brief Symmetrically encrypts a string and returns keyfile content
* @param $plainContent content to be encrypted in keyfile
* @returns encrypted content combined with IV
* @note IV need not be specified, as it will be stored in the returned keyfile
* and remain accessible therein.
*/
public static function symmetricEncryptFileContent( $plainContent, $passphrase = '' ) {
if ( !$plainContent ) {
return false;
}
$iv = self::generateIv();
if ( $encryptedContent = self::encrypt( $plainContent, $iv, $passphrase ) ) {
// Combine content to encrypt with IV identifier and actual IV
$combinedKeyfile = $encryptedContent . '00iv00' . $iv;
return $combinedKeyfile;
} else {
\OC_Log::write( 'Encryption library', 'Encryption (symmetric) of keyfile content failed' , \OC_Log::ERROR );
return false;
}
}
/**
* @brief Symmetrically decrypts keyfile content
* @param string $source
* @param string $target
* @param string $key the decryption key
*
* This function decrypts a file
*/
public static function symmetricDecryptFileContent( $keyfileContent, $passphrase = '' ) {
if ( !$keyfileContent ) {
return false;
}
// Fetch IV from end of file
$iv = substr( $keyfileContent, -16 );
// Remove IV and IV identifier text to expose encrypted content
$encryptedContent = substr( $keyfileContent, 0, -22 );
if ( $plainContent = self::decrypt( $encryptedContent, $iv, $passphrase ) ) {
return $plainContent;
} else {
\OC_Log::write( 'Encryption library', 'Decryption (symmetric) of keyfile content failed' , \OC_Log::ERROR );
return false;
}
}
/**
* @brief Creates symmetric keyfile content using a generated key
* @param string $plainContent content to be encrypted
* @returns array keys: key, encrypted
* @note symmetricDecryptFileContent() can be used to decrypt files created using this method
*
* This function decrypts a file
*/
public static function symmetricEncryptFileContentKeyfile( $plainContent ) {
$key = self::generateKey();
if( $encryptedContent = self::symmetricEncryptFileContent( $plainContent, $key ) ) {
return array(
'key' => $key
, 'encrypted' => $encryptedContent
);
} else {
return false;
}
}
/**
* @brief Create asymmetrically encrypted keyfile content using a generated key
* @param string $plainContent content to be encrypted
* @returns array keys: key, encrypted
* @note symmetricDecryptFileContent() can be used to decrypt files created using this method
*
* This function decrypts a file
*/
public static function multiKeyEncrypt( $plainContent, array $publicKeys ) {
$envKeys = array();
if( openssl_seal( $plainContent, $sealed, $envKeys, $publicKeys ) ) {
return array(
'keys' => $envKeys
, 'encrypted' => $sealed
);
} else {
return false;
}
}
/**
* @brief Asymmetrically encrypt a file using multiple public keys
* @param string $plainContent content to be encrypted
* @returns array keys: key, encrypted
* @note symmetricDecryptFileContent() can be used to decrypt files created using this method
*
* This function decrypts a file
*/
public static function multiKeyDecrypt( $encryptedContent, $envKey, $privateKey ) {
if ( !$encryptedContent ) {
return false;
}
if ( openssl_open( $encryptedContent, $plainContent, $envKey, $privateKey ) ) {
return $plainContent;
} else {
\OC_Log::write( 'Encryption library', 'Decryption (asymmetric) of sealed content failed' , \OC_Log::ERROR );
return false;
}
}
/**
* @brief Asymetrically encrypt a string using a public key
* @returns encrypted file
*/
public static function keyEncrypt( $plainContent, $publicKey ) {
openssl_public_encrypt( $plainContent, $encryptedContent, $publicKey );
return $encryptedContent;
}
/**
* @brief Asymetrically decrypt a file using a private key
* @returns decrypted file
*/
public static function keyDecrypt( $encryptedContent, $privatekey ) {
openssl_private_decrypt( $encryptedContent, $plainContent, $privatekey );
return $plainContent;
}
/**
* @brief Generate a pseudo random 1024kb ASCII key
* @returns $key Generated key
*/
public static function generateIv() {
if ( $random = openssl_random_pseudo_bytes( 13, $strong ) ) {
if ( !$strong ) {
// If OpenSSL indicates randomness is insecure, log error
\OC_Log::write( 'Encryption library', 'Insecure symmetric key was generated using openssl_random_pseudo_bytes()' , \OC_Log::WARN );
}
$iv = substr( base64_encode( $random ), 0, -4 );
return $iv;
} else {
return false;
}
}
/**
* @brief Generate a pseudo random 1024kb ASCII key
* @returns $key Generated key
*/
public static function generateKey() {
// $key = mt_rand( 10000, 99999 ) . mt_rand( 10000, 99999 ) . mt_rand( 10000, 99999 ) . mt_rand( 10000, 99999 );
// Generate key
if ( $key = base64_encode( openssl_random_pseudo_bytes( 768000, $strong ) ) ) {
if ( !$strong ) {
// If OpenSSL indicates randomness is insecure, log error
\OC_Log::write( 'Encryption library', 'Insecure symmetric key was generated using openssl_random_pseudo_bytes()' , \OC_Log::WARN );
}
return $key;
} else {
return false;
}
}
public static function changekeypasscode($oldPassword, $newPassword) {
if(OCP\User::isLoggedIn()){
$username=OCP\USER::getUser();
$view=new OC_FilesystemView('/'.$username);
// read old key
$key=$view->file_get_contents('/encryption.key');
// decrypt key with old passcode
$key=OC_Crypt::decrypt($key, $oldPassword);
// encrypt again with new passcode
$key=OC_Crypt::encrypt($key, $newPassword);
// store the new key
$view->file_put_contents('/encryption.key', $key );
}
}
}
}
/**
* @brief Create a new encryption keypair
* @return array publicKey, privatekey
*/
public static function createKeypair() {
$res = openssl_pkey_new();
// Get private key
openssl_pkey_export( $res, $privateKey );
// Get public key
$publicKey = openssl_pkey_get_details( $res );
$publicKey = $publicKey['key'];
return( array( 'publicKey' => $publicKey, 'privateKey' => $privateKey ) );
}
/**
* @brief Check if a file's contents contains an IV and is symmetrically encrypted
* @return true / false
*/
public static function isEncryptedContent( $content ) {
if ( !$content ) {
return false;
}
// Fetch encryption metadata from end of file
$meta = substr( $content, -22 );
// Fetch IV from end of file
$iv = substr( $meta, -16 );
// Fetch identifier from start of metadata
$identifier = substr( $meta, 0, 6 );
if ( $identifier == '00iv00') {
return true;
} else {
return false;
}
}
/**
* @brief Check if a file is encrypted via legacy system
* @return true / false
*/
public static function isLegacyEncryptedContent( $content, $path ) {
// Fetch all file metadata from DB
$metadata = \OC_FileCache_Cached::get( $content, '' );
// If a file is flagged with encryption in DB, but isn't a valid content + IV combination, it's probably using the legacy encryption system
if (
$content
and isset( $metadata['encrypted'] )
and $metadata['encrypted'] === true
and !self::isEncryptedContent( $content )
) {
return true;
} else {
return false;
}
}
/**
* @brief Symmetrically encrypt a string
* @returns encrypted file
*/
public static function encrypt( $plainContent, $iv, $passphrase = '' ) {
if ( $encryptedContent = openssl_encrypt( $plainContent, 'AES-128-CFB', $passphrase, false, $iv ) ) {
return $encryptedContent;
} else {
\OC_Log::write( 'Encryption library', 'Encryption (symmetric) of content failed' , \OC_Log::ERROR );
return false;
}
}
/**
* @brief Symmetrically decrypt a string
* @returns decrypted file
*/
public static function decrypt( $encryptedContent, $iv, $passphrase ) {
if ( $plainContent = openssl_decrypt( $encryptedContent, 'AES-128-CFB', $passphrase, false, $iv ) ) {
return $plainContent;
} else {
\OC_Log::write( 'Encryption library', 'Decryption (symmetric) of content failed' , \OC_Log::ERROR );
return false;
}
}
/**
* @brief Symmetrically encrypts a string and returns keyfile content
* @param $plainContent content to be encrypted in keyfile
* @returns encrypted content combined with IV
* @note IV need not be specified, as it will be stored in the returned keyfile
* and remain accessible therein.
*/
public static function symmetricEncryptFileContent( $plainContent, $passphrase = '' ) {
if ( !$plainContent ) {
return false;
}
$iv = self::generateIv();
if ( $encryptedContent = self::encrypt( $plainContent, $iv, $passphrase ) ) {
// Combine content to encrypt with IV identifier and actual IV
$combinedKeyfile = $encryptedContent . '00iv00' . $iv;
return $combinedKeyfile;
} else {
\OC_Log::write( 'Encryption library', 'Encryption (symmetric) of keyfile content failed' , \OC_Log::ERROR );
return false;
}
}
/**
* @brief Symmetrically decrypts keyfile content
* @param string $source
* @param string $target
* @param string $key the decryption key
*
* This function decrypts a file
*/
public static function symmetricDecryptFileContent( $keyfileContent, $passphrase = '' ) {
if ( !$keyfileContent ) {
return false;
}
// Fetch IV from end of file
$iv = substr( $keyfileContent, -16 );
// Remove IV and IV identifier text to expose encrypted content
$encryptedContent = substr( $keyfileContent, 0, -22 );
if ( $plainContent = self::decrypt( $encryptedContent, $iv, $passphrase ) ) {
return $plainContent;
} else {
\OC_Log::write( 'Encryption library', 'Decryption (symmetric) of keyfile content failed' , \OC_Log::ERROR );
return false;
}
}
/**
* @brief Creates symmetric keyfile content using a generated key
* @param string $plainContent content to be encrypted
* @returns array keys: key, encrypted
* @note symmetricDecryptFileContent() can be used to decrypt files created using this method
*
* This function decrypts a file
*/
public static function symmetricEncryptFileContentKeyfile( $plainContent ) {
$key = self::generateKey();
if( $encryptedContent = self::symmetricEncryptFileContent( $plainContent, $key ) ) {
return array(
'key' => $key
, 'encrypted' => $encryptedContent
);
} else {
return false;
}
}
/**
* @brief Create asymmetrically encrypted keyfile content using a generated key
* @param string $plainContent content to be encrypted
* @returns array keys: key, encrypted
* @note symmetricDecryptFileContent() can be used to decrypt files created using this method
*
* This function decrypts a file
*/
public static function multiKeyEncrypt( $plainContent, array $publicKeys ) {
$envKeys = array();
if( openssl_seal( $plainContent, $sealed, $envKeys, $publicKeys ) ) {
return array(
'keys' => $envKeys
, 'encrypted' => $sealed
);
} else {
return false;
}
}
/**
* @brief Asymmetrically encrypt a file using multiple public keys
* @param string $plainContent content to be encrypted
* @returns array keys: key, encrypted
* @note symmetricDecryptFileContent() can be used to decrypt files created using this method
*
* This function decrypts a file
*/
public static function multiKeyDecrypt( $encryptedContent, $envKey, $privateKey ) {
if ( !$encryptedContent ) {
return false;
}
if ( openssl_open( $encryptedContent, $plainContent, $envKey, $privateKey ) ) {
return $plainContent;
} else {
\OC_Log::write( 'Encryption library', 'Decryption (asymmetric) of sealed content failed' , \OC_Log::ERROR );
return false;
}
}
/**
* @brief Asymetrically encrypt a string using a public key
* @returns encrypted file
*/
public static function keyEncrypt( $plainContent, $publicKey ) {
openssl_public_encrypt( $plainContent, $encryptedContent, $publicKey );
return $encryptedContent;
}
/**
* @brief Asymetrically decrypt a file using a private key
* @returns decrypted file
*/
public static function keyDecrypt( $encryptedContent, $privatekey ) {
openssl_private_decrypt( $encryptedContent, $plainContent, $privatekey );
return $plainContent;
}
/**
* @brief Generate a pseudo random 1024kb ASCII key
* @returns $key Generated key
*/
public static function generateIv() {
if ( $random = openssl_random_pseudo_bytes( 13, $strong ) ) {
if ( !$strong ) {
// If OpenSSL indicates randomness is insecure, log error
\OC_Log::write( 'Encryption library', 'Insecure symmetric key was generated using openssl_random_pseudo_bytes()' , \OC_Log::WARN );
}
$iv = substr( base64_encode( $random ), 0, -4 );
return $iv;
} else {
return false;
}
}
/**
* @brief Generate a pseudo random 1024kb ASCII key
* @returns $key Generated key
*/
public static function generateKey() {
// $key = mt_rand( 10000, 99999 ) . mt_rand( 10000, 99999 ) . mt_rand( 10000, 99999 ) . mt_rand( 10000, 99999 );
// Generate key
if ( $key = base64_encode( openssl_random_pseudo_bytes( 768000, $strong ) ) ) {
if ( !$strong ) {
// If OpenSSL indicates randomness is insecure, log error
\OC_Log::write( 'Encryption library', 'Insecure symmetric key was generated using openssl_random_pseudo_bytes()' , \OC_Log::WARN );
}
return $key;
} else {
return false;
}
}
public static function changekeypasscode($oldPassword, $newPassword) {
if(OCP\User::isLoggedIn()){
$username=OCP\USER::getUser();
$view=new OC_FilesystemView('/'.$username);
// read old key
$key=$view->file_get_contents('/encryption.key');
// decrypt key with old passcode
$key=OC_Crypt::decrypt($key, $oldPassword);
// encrypt again with new passcode
$key=OC_Crypt::encrypt($key, $newPassword);
// store the new key
$view->file_put_contents('/encryption.key', $key );
}
}
}
?>

View File

@ -27,7 +27,7 @@ namespace OCA_Encryption;
*/
class Keymanager {
# TODO: make all dependencies explicit, such as ocfsview objects, by adding them as method arguments (dependency injection)
# TODO: make all dependencies (including static classes) explicit, such as ocfsview objects, by adding them as method arguments (dependency injection)
/**
* @brief retrieve private key from a user
@ -128,27 +128,30 @@ class Keymanager {
* @param string $key
* @return bool true/false
*/
public static function setFileKey( $userId, $path, $key ) {
public static function setFileKey( $user, $path, $key, $view, $dbClassName, $fileProxyClassName ) {
\OC_FileProxy::$enabled = false;
$fileProxyClassName::$enabled = false;
$targetpath = ltrim( $path, '/' );
$user = $userId;
// update $keytarget and $user if key belongs to a file shared by someone else
$query = \OC_DB::prepare( "SELECT uid_owner, source, target FROM `*PREFIX*sharing` WHERE target = ? AND uid_shared_with = ?" );
$query = $dbClassName::prepare( "SELECT uid_owner, source, target FROM `*PREFIX*sharing` WHERE target = ? AND uid_shared_with = ?" );
$result = $query->execute( array ( '/'.$userId.'/files/'.$targetpath, $userId ) );
$result = $query->execute( array ( '/'.$user.'/files/'.$targetpath, $user ) );
if ( $row = $result->fetchRow( ) ) {
$targetpath = $row['source'];
$targetpath_parts=explode( '/',$targetpath );
$user = $targetpath_parts[1];
$targetpath = str_replace( '/'.$user.'/files/', '', $targetpath );
//TODO: check for write permission on shared file once the new sharing API is in place
}
$view = new \OC_FilesystemView( '/' . $user . '/files_encryption/keyfiles' );
$targetpath = $row['source'];
$targetpath_parts=explode( '/',$targetpath );
$user = $targetpath_parts[1];
$targetpath = str_replace( '/'.$user.'/files/', '', $targetpath );
//TODO: check for write permission on shared file once the new sharing API is in place
}
$path_parts = pathinfo( $targetpath );
@ -156,7 +159,7 @@ class Keymanager {
$result = $view->file_put_contents( '/' . $targetpath . '.key', $key );
\OC_FileProxy::$enabled = true;
$fileProxyClassName::$enabled = true;
return $result;
}

View File

@ -115,8 +115,11 @@ class Proxy extends \OC_FileProxy {
$filePath = '/' . implode( '/', $filePath );
# TODO: make keyfile dir dynamic from app config
$view = new \OC_FilesystemView( '/' . \OCP\USER::getUser() . '/files_encryption/keyfiles' );
// Save keyfile for newly encrypted file in parallel directory tree
Keymanager::setFileKey( \OCP\USER::getUser(), $filePath, $encrypted['key'] );
Keymanager::setFileKey( \OCP\USER::getUser(), $filePath, $encrypted['key'], $view, '\OC_DB', '\OC_FileProxy' );
// Update the file cache with file info
\OC_FileCache::put( $path, array( 'encrypted'=>true, 'size' => $size ), '' );