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SynCrypto.pas
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/// fast cryptographic routines (hashing and cypher)
// - implements AES, XOR, ADLER32, MD5, RC4, SHA1, SHA256 algorithms
// - optimized for speed (tuned assembler and AES-NI / PADLOCK support)
// - this unit is a part of the freeware Synopse mORMot framework,
// licensed under a MPL/GPL/LGPL tri-license; version 1.18
unit SynCrypto;
(*
This file is part of Synopse framework.
Synopse framework. Copyright (C) 2017 Arnaud Bouchez
Synopse Informatique - http://synopse.info
*** BEGIN LICENSE BLOCK *****
Version: MPL 1.1/GPL 2.0/LGPL 2.1
The contents of this file are subject to the Mozilla Public License Version
1.1 (the "License"); you may not use this file except in compliance with
the License. You may obtain a copy of the License at
http://www.mozilla.org/MPL
Software distributed under the License is distributed on an "AS IS" basis,
WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
for the specific language governing rights and limitations under the License.
The Original Code is Synopse mORMot framework.
The Initial Developer of the Original Code is Arnaud Bouchez.
Portions created by the Initial Developer are Copyright (C) 2017
the Initial Developer. All Rights Reserved.
Contributor(s):
- Alfred Glaenzer (alf)
- EvaF
- Intel's sha256_sse4.asm under under a three-clause Open Software license
- Johan Bontes
- souchaud
- Wolfgang Ehrhardt under zlib license for AES "pure pascal" versions
Alternatively, the contents of this file may be used under the terms of
either the GNU General Public License Version 2 or later (the "GPL"), or
the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
in which case the provisions of the GPL or the LGPL are applicable instead
of those above. If you wish to allow use of your version of this file only
under the terms of either the GPL or the LGPL, and not to allow others to
use your version of this file under the terms of the MPL, indicate your
decision by deleting the provisions above and replace them with the notice
and other provisions required by the GPL or the LGPL. If you do not delete
the provisions above, a recipient may use your version of this file under
the terms of any one of the MPL, the GPL or the LGPL.
***** END LICENSE BLOCK *****
Synopse Cryptographic routines
==============================
- fastest ever 100% Delphi (and asm ;) code
- AES Crypto(128,192,256 bits key) with optimized asm version
and multi-threaded code for multi-core CPU for blocks > 512 KB
- XOR Crypto (32 bits key) - very fast with variable or fixed key
- RC4 Crypto - weak, but simple and standard (used e.g. by SynPdf)
- ADLER32 - 32 bits fast Hash with optimized asm version
- MD5 - standard fast 128 bits Hash
- SHA1 - 160 bits Secure Hash
- SHA256 - 256 bits Secure Hash with optimized asm version
- hardware AES-NI and SHA-SSE4 support for latest CPU
- VIA PADLOCK optional support - native .o code on linux or .dll (Win32)
(tested on a Dedibox C7 (rev1) linux server - need validation for Win32)
- Microsoft AES Cryptographic Provider optional support via CryptoAPI
Source code licenced under the MPL:
see http://www.mozilla.org/MPL/MPL-1.1.html
Benchmark on my AMD-64 TL-56 dualcore-CPU:
==========================================
Testing with blocks of 16KB each
crc32 624 MB/s
adler32 pas 571 MB/s asm 1304 MB/s
MD5 176 MB/s
SHA1 101 MB/s
SHA256 63 MB/s
AES128 cypher 84 MB/s uncypher 81 MB/s asm version
AES128 cypher 57 MB/s uncypher 57 MB/s pascal version
AES192 cypher 72 MB/s uncypher 70 MB/s asm version
AES192 cypher 48 MB/s uncypher 48 MB/s pascal version
AES256 cypher 62 MB/s uncypher 61 MB/s asm version
AES256 cypher 42 MB/s uncypher 42 MB/s pascal version
XorBlock 3463 MB/s (very fast, since with 16KB data remain in L2 cache)
XorOffset 3425 MB/s
XorConst 5940 MB/s (even faster, since no table used -> all in L1 cache)
Testing with blocks of 1024KB each (for AES: block >512KB -> uses dualcore)
crc32 577 MB/s
adler32 pas 529 MB/s asm 1003 MB/s
MD5 176 MB/s
SHA1 100 MB/s
SHA256 63 MB/s
AES128 cypher 129 MB/s uncypher 130 MB/s asm version
AES128 cypher 96 MB/s uncypher 95 MB/s pascal version
AES192 cypher 107 MB/s uncypher 114 MB/s asm version
AES192 cypher 83 MB/s uncypher 85 MB/s pascal version
AES256 cypher 98 MB/s uncypher 105 MB/s asm version
AES256 cypher 76 MB/s uncypher 76 MB/s pascal version
XorBlock 1423 MB/s (we reach the memory control bandwidth)
XorOffset 1325 MB/s
XorConst 1506 MB/s
Testing with blocks of 4096KB each (for AES: block >512KB -> uses dualcore)
crc32 578 MB/s
adler32 pas 525 MB/s asm 984 MB/s
MD5 175 MB/s
SHA1 100 MB/s
SHA256 63 MB/s
AES128 cypher 159 MB/s uncypher 147 MB/s asm version
AES128 cypher 107 MB/s uncypher 109 MB/s pascal version
AES192 cypher 134 MB/s uncypher 128 MB/s asm version
AES192 cypher 90 MB/s uncypher 92 MB/s pascal version
AES256 cypher 118 MB/s uncypher 113 MB/s asm version
AES256 cypher 80 MB/s uncypher 81 MB/s pascal version
XorBlock 1385 MB/s
XorOffset 1292 MB/s
XorConst 1479 MB/s
Benchmark on a C7 Dedibox (USEPADLOCK version):
===============================================
Testing with blocks of 16KB each
crc32 402 MB/s
adler32 pas 274 MB/s asm 542 MB/s libz.so 414 MB/s
MD5 126 MB/s
SHA1 480 MB/s
SHA256 458 MB/s
AES128 cypher 1566 MB/s uncypher 1560 MB/s
AES192 cypher 1421 MB/s uncypher 1422 MB/s
AES256 cypher 1237 MB/s uncypher 1247 MB/s
XorBlock 2336 MB/s
XorOffset 1807 MB/s
XorConst 3154 MB/s
Testing with blocks of 1024KB each
crc32 352 MB/s
adler32 pas 256 MB/s asm 395 MB/s libz.so 361 MB/s
MD5 123 MB/s
SHA1 324 MB/s
SHA256 324 MB/s
AES128 cypher 552 MB/s uncypher 552 MB/s
AES192 cypher 552 MB/s uncypher 552 MB/s
AES256 cypher 552 MB/s uncypher 552 MB/s
XorBlock 354 MB/s
XorOffset 373 MB/s
XorConst 511 MB/s
Testing with blocks of 4096KB each
crc32 352 MB/s
adler32 pas 255 MB/s asm 395 MB/s libz.so 361 MB/s
MD5 124 MB/s
SHA1 324 MB/s
SHA256 326 MB/s
AES128 cypher 552 MB/s uncypher 552 MB/s
AES192 cypher 552 MB/s uncypher 552 MB/s
AES256 cypher 552 MB/s uncypher 552 MB/s
XorBlock 352 MB/s
XorOffset 368 MB/s
XorConst 510 MB/s
Conclusion:
- USETHREADSFORBIGAESBLOCKS will help on modern multi-threaded CPU
- AES speed: W.Ehrhardt's pascal is 55MB/s, A.Bouchez's asm is 84MB/s
- AES-256 is faster than a simple XOR() on a dedibox with a C7 cpu ;)
- see below for benchmarks using AES-NI or SHA-256-SSE4, which induce
a huge performance boost
Initial version (C) 2008-2009 Arnaud Bouchez http://bouchez.info
Revision History:
Version 1.0
- initial release on Internet, with MyCrypto unit name
Version 1.1
- updated release, with new optimized AES i386 assembler implementation
and no FastCode dependency (CpuCount is taken from Windows API)
Version 1.4 - February 8, 2010
- whole Synopse SQLite3 database framework released under the GNU Lesser
General Public License version 3, instead of generic "Public Domain"
Version 1.8
- mostly code review for Delphi 2009/2010 integration (unit uses now
SynCommons string types definitions)
Version 1.9
- now use direct Windows threads, since we don't need any exception handling
nor memory usage inside the AES encryption Thread handler
-> avoid classes.TThread and system.BeginThread() use
-> application is still "officialy" mono-threaded (i.e. IsMultiThread=false),
for faster System.pas and FastMM4 (prevent CPU locking - see
http://synopse.info/forum/viewtopic.php?id=57 about Delphi & multi-core)
- some other minor fixes and enhancements
Version 1.10
- code modifications to compile with Delphi 6 compiler
Version 1.13
- code modifications to compile with Delphi 5 compiler
Version 1.15
- unit now tested with Delphi XE2 (32 Bit)
Version 1.16
- added TAESECB, TAESCBC, TAESCFB, TAESOFB and TAESCTR classes to handle AES
encryption of memory buffers in ECB, CBC, CFB, OFB and CTR mode (including
PKCS7 padding)
- added pure pascal version (for XE2 64 compilation) of all algorithms
Version 1.18
- added AES-NI hardware support on newer CPUs, for huge performance boost
and enhanced security
- AES encryption will compute its own tables, to get rid of 4KB of const
- optimized x86 asm version for MD5
- tested compilation for Win64 platform
- run with FPC under Win32 and Linux (including AES-NI support), and Kylix
- added Intel's SSE4 x64 optimized asm for SHA-256 on Win64
- added overloaded procedure TMD5.Final() and function SHA256()
- introduce ESynCrypto exception class dedicated to this unit
- added AES encryption using official Microsoft AES Cryptographic Provider
(CryptoAPI) via TAESECB_API, TAESCBC_API, TAESCFB_API and TAESOFB_API -
our optimized asm version is faster, so is still our default/preferred
- added optional IVAtBeginning parameter to EncryptPKCS7/DecryptPKC7 methods
- get rid of the unsafe IV parameter for TAES* classes constructors
- added CompressShaAes() and global CompressShaAesKey and CompressShaAesClass
variables to be used by THttpSocket.RegisterCompress
- introduce new TRC4 object for RC4 encryption algorithm
- introducing HMAC_SHA1/SHA256 and PBKDF2_HMAC_SHA1/SHA256 functions
- removed several compilation hints when assertions are set to off
*)
interface
{$I Synopse.inc} // define HASINLINE USETYPEINFO CPU32 CPU64 OWNNORMTOUPPER
{.$define USEPADLOCK}
{.$define PUREPASCAL} // for debug
{$ifdef Linux}
{$undef USETHREADSFORBIGAESBLOCKS} // uses low-level WinAPI threading
{$ifdef KYLIX3}
{.$define USEPADLOCK} // dedibox Linux tested only
{$endif}
{$else}
{$ifndef DELPHI5OROLDER}
// on Windows: enable Microsoft AES Cryptographic Provider (XP SP3 and up)
{$define USE_PROV_RSA_AES}
{$endif}
// on Windows: will use Threads for very big blocks (>512KB) if multi-CPU
{$define USETHREADSFORBIGAESBLOCKS}
{$endif}
{$ifdef USEPADLOCK}
{$ifdef MSWINDOWS}
{$define USEPADLOCKDLL} // Win32: we can use LibPadlock.dll
{$else}
{.$define PADLOCKDEBUG} // display message before using padlock
{.$define USEPADLOCKDLL} // Linux: use fast .o linked code
{$endif}
{$endif}
uses
{$ifdef MSWINDOWS}
Windows,
{$else}
{$ifdef KYLIX3}
LibC,
SynKylix,
{$endif}
{$ifdef FPC}
SynFPCLinux,
{$endif FPC}
{$endif}
SysUtils,
{$ifndef LVCL}
{$ifndef DELPHI5OROLDER}
RTLConsts,
{$endif}
{$endif}
Classes,
SynLZ, // already included in SynCommons, and used by CompressShaAes()
SynCommons;
{$ifdef USEPADLOCK}
var
/// if dll/so and VIA padlock compatible CPU are present
padlock_available: boolean = false;
{$endif}
const
/// hide all AES Context complex code
AESContextSize = 276 {$ifdef USEPADLOCK}+sizeof(pointer){$endif};
/// hide all SHA Context complex code
SHAContextSize = 108;
/// power of two for a standard AES block size during cypher/uncypher
// - to be used as 1 shl AESBlockShift or 1 shr AESBlockShift for fast div/mod
AESBlockShift = 4;
/// bit mask for fast modulo of AES block size
AESBlockMod = 15;
/// maximum AES key size (in bytes)
AESKeySize = 256 div 8;
type
/// class of Exceptions raised by this unit
ESynCrypto = class(ESynException);
PAESBlock = ^TAESBlock;
/// 128 bits memory block for AES data cypher/uncypher
TAESBlock = THash128;
/// 256 bits memory block for maximum AES key storage
TAESKey = THash256;
/// stores an array of THash128 to check for their unicity
// - used e.g. to implement TAESAbstract.IVHistoryDepth property
THash128History = {$ifndef UNICODE}object{$else}record{$endif}
private
Previous: array of THash128Rec;
Index: integer;
public
/// how many THash128 values can be stored
Depth: integer;
/// how many THash128 values are currently stored
Count: integer;
/// initialize the storage for a given history depth
procedure Init(size: integer);
/// O(n) fast search of a hash value in the stored entries
// - returns true if the hash was found, or false if it did not appear
function Exists(const hash: THash128): boolean;
/// add a hash value to the stored entries, checking for duplicates
// - returns true if the hash was added, or false if it did already appear
function Add(const hash: THash128): boolean;
end;
PAES = ^TAES;
/// handle AES cypher/uncypher
// - this is the default Electronic codebook (ECB) mode
// - this class will use AES-NI hardware instructions, if available
{$ifdef USEPADLOCK}
// - this class will use VIA PadLock instructions, if available
{$endif}
TAES = {$ifndef UNICODE}object{$else}record{$endif}
private
Context: packed array[1..AESContextSize] of byte;
{$ifdef USEPADLOCK}
function DoPadlockInit(const Key; KeySize: cardinal): boolean;
{$endif}
public
/// Initialize AES contexts for cypher
// - first method to call before using this class
// - KeySize is in bits, i.e. 128,192,256
function EncryptInit(const Key; KeySize: cardinal): boolean;
/// encrypt an AES data block into another data block
procedure Encrypt(const BI: TAESBlock; var BO: TAESBlock); overload;
/// encrypt an AES data block
procedure Encrypt(var B: TAESBlock); overload;
/// Initialize AES contexts for uncypher
function DecryptInit(const Key; KeySize: cardinal): boolean;
/// decrypt an AES data block
procedure Decrypt(var B: TAESBlock); overload;
/// decrypt an AES data block into another data block
procedure Decrypt(const BI: TAESBlock; var BO: TAESBlock); overload;
/// Finalize AES contexts for both cypher and uncypher
// - would fill the TAES instance with zeros, for safety
// - is only mandatoy when padlock is used
procedure Done;
/// generic initialization method for AES contexts
// - call either EncryptInit() either DecryptInit() method
function DoInit(const Key; KeySize: cardinal; doEncrypt: boolean): boolean;
/// perform the AES cypher or uncypher to continuous memory blocks
// - call either Encrypt() either Decrypt() method
procedure DoBlocks(pIn, pOut: PAESBlock; out oIn, oOut: PAESBLock; Count: integer; doEncrypt: boolean); overload;
/// perform the AES cypher or uncypher to continuous memory blocks
// - call either Encrypt() either Decrypt() method
procedure DoBlocks(pIn, pOut: PAESBlock; Count: integer; doEncrypt: boolean); overload;
{$ifdef USETHREADSFORBIGAESBLOCKS}
/// perform the AES cypher or uncypher to continuous memory blocks
// - this special method will use Threads for bigs blocks (>512KB) if multi-CPU
// - call either Encrypt() either Decrypt() method
procedure DoBlocksThread(var bIn, bOut: PAESBlock; Count: integer; doEncrypt: boolean);
{$endif}
/// TRUE if the context was initialized via EncryptInit/DecryptInit
function Initialized: boolean;
/// return TRUE if the AES-NI instruction sets are available on this CPU
function UsesAESNI: boolean; {$ifdef HASINLINE}inline;{$endif}
end;
/// class-reference type (metaclass) of an AES cypher/uncypher
TAESAbstractClass = class of TAESAbstract;
/// used internally by TAESAbstract to detect replay attacks
// - when EncryptPKCS7/DecryptPKCS7 are used with IVAtBeginning=true, and
// IVReplayAttackCheck property contains repCheckedIfAvailable or repMandatory
// - EncryptPKCS7 will encrypt this record (using the global shared
// AESIVCTR_KEY over AES-128) to create a random IV, as a secure
// cryptographic pseudorandom number generator (CSPRNG), nonce and ctr
// ensuring 96 bits of entropy
// - DecryptPKCS7 will decode and ensure that the IV has an increasing CTR
// - memory size matches an TAESBlock on purpose, for direct encryption
TAESIVCTR = packed record
/// 8 bytes of random value
nonce: Int64;
/// contains the crc32c hash of the block cipher mode (e.g. 'AESCFB')
// - when magic won't match (i.e. in case of mORMot revision < 3063), the
// check won't be applied in DecryptPKCS7: this security feature is
// backward compatible if IVReplayAttackCheck is repCheckedIfAvailable,
// but will fail for repMandatory
magic: cardinal;
/// an increasing counter, used to detect replay attacks
// - is set to a 32-bit random value at initialization
// - is increased by one for every EncryptPKCS7, so can be checked against
// replay attack in DecryptPKCS7, and implement a safe CSPRNG for stored IV
ctr: cardinal;
end;
/// how TAESAbstract.DecryptPKCS7 should detect replay attack
// - repNoCheck and repCheckedIfAvailable will be compatible with older
// versions of the protocol, but repMandatory will reject any encryption
// without the TAESIVCTR algorithm
TAESIVReplayAttackCheck = (repNoCheck, repCheckedIfAvailable, repMandatory);
/// handle AES cypher/uncypher with chaining
// - use any of the inherited implementation, corresponding to the chaining
// mode required - TAESECB, TAESCBC, TAESCFB, TAESOFB and TAESCTR classes to
// handle in ECB, CBC, CFB, OFB and CTR mode (including PKCS7-like padding)
TAESAbstract = class
protected
fKeySize: cardinal;
fKeySizeBytes: cardinal;
fKey: TAESKey;
fIV: TAESBlock;
fIVCTR: TAESIVCTR;
fIVCTRState: (ctrUnknown, ctrUsed, ctrNotused);
fIVHistoryDec: THash128History;
fIVReplayAttackCheck: TAESIVReplayAttackCheck;
procedure SetIVHistory(aDepth: integer);
procedure DecryptLen(var InputLen,ivsize: integer; Input: pointer;
IVAtBeginning: boolean);
public
/// Initialize AES contexts for cypher
// - first method to call before using this class
// - KeySize is in bits, i.e. 128,192,256
constructor Create(const aKey; aKeySize: cardinal); virtual;
/// Initialize AES contexts for cypher
// - here the Key is supplied as a string, and will be hashed using SHA-256
constructor CreateFromSha256(const aKey: RawUTF8); virtual;
/// compute a class instance similar to this one
function Clone: TAESAbstract; virtual;
/// compute a class instance similar to this one, for performing the
// reverse encryption/decryption process
// - this default implementation calls Clone, but CFB/OFB/CTR chaining modes
// using only AES encryption will return self to avoid creating two instances
// - warning: to be used only with IVAtBeginning=false
function CloneEncryptDecrypt: TAESAbstract; virtual;
/// release the used instance memory and resources
// - also fill the secret fKey buffer with zeros, for safety
destructor Destroy; override;
/// perform the AES cypher in the corresponding mode
// - when used in block chaining mode, you should have set the IV property
procedure Encrypt(BufIn, BufOut: pointer; Count: cardinal); virtual; abstract;
/// perform the AES un-cypher in the corresponding mode
// - when used in block chaining mode, you should have set the IV property
procedure Decrypt(BufIn, BufOut: pointer; Count: cardinal); virtual; abstract;
/// encrypt a memory buffer using a PKCS7 padding pattern
// - PKCS7 padding is described in RFC 5652 - it will add up to 16 bytes to
// the input buffer; note this method uses the padding only, not the whole
// PKCS#7 Cryptographic Message Syntax
// - if IVAtBeginning is TRUE, a random Initialization Vector will be computed,
// and stored at the beginning of the output binary buffer - this IV may
// contain an internal encrypted CTR, to detect any replay attack attempt,
// if IVReplayAttackCheck is set to repCheckedIfAvailable or repMandatory
function EncryptPKCS7(const Input: RawByteString; IVAtBeginning: boolean=false): RawByteString; overload;
/// decrypt a memory buffer using a PKCS7 padding pattern
// - PKCS7 padding is described in RFC 5652 - it will trim up to 16 bytes from
// the input buffer; note this method uses the padding only, not the whole
// PKCS#7 Cryptographic Message Syntax
// - if IVAtBeginning is TRUE, the Initialization Vector will be taken
// from the beginning of the input binary buffer - if IVReplayAttackCheck is
// set, this IV will be validated to contain an increasing encrypted CTR,
// and raise an ESynCrypto when a replay attack attempt is detected
function DecryptPKCS7(const Input: RawByteString; IVAtBeginning: boolean=false): RawByteString; overload;
/// encrypt a memory buffer using a PKCS7 padding pattern
// - PKCS7 padding is described in RFC 5652 - it will add up to 16 bytes to
// the input buffer; note this method uses the padding only, not the whole
// PKCS#7 Cryptographic Message Syntax
// - if IVAtBeginning is TRUE, a random Initialization Vector will be computed,
// and stored at the beginning of the output binary buffer - this IV may
// contain an internal encrypted CTR, to detect any replay attack attempt,
// if IVReplayAttackCheck is set to repCheckedIfAvailable or repMandatory
function EncryptPKCS7(const Input: TBytes; IVAtBeginning: boolean=false): TBytes; overload;
/// decrypt a memory buffer using a PKCS7 padding pattern
// - PKCS7 padding is described in RFC 5652 - it will trim up to 16 bytes from
// the input buffer; note this method uses the padding only, not the whole
// PKCS#7 Cryptographic Message Syntax
// - if IVAtBeginning is TRUE, the Initialization Vector will be taken
// from the beginning of the input binary buffer - if IVReplayAttackCheck is
// set, this IV will be validated to contain an increasing encrypted CTR,
// and raise an ESynCrypto when a replay attack attempt is detected
function DecryptPKCS7(const Input: TBytes; IVAtBeginning: boolean=false): TBytes; overload;
/// compute how many bytes would be needed in the output buffer, when
// encrypte using a PKCS7 padding pattern
// - could be used to pre-compute the OutputLength for EncryptPKCS7Buffer()
// - PKCS7 padding is described in RFC 5652 - it will add up to 16 bytes to
// the input buffer; note this method uses the padding only, not the whole
// PKCS#7 Cryptographic Message Syntax
function EncryptPKCS7Length(InputLen: cardinal; IVAtBeginning: boolean): cardinal;
{$ifdef HASINLINE}inline;{$endif}
/// encrypt a memory buffer using a PKCS7 padding pattern
// - PKCS7 padding is described in RFC 5652 - it will add up to 16 bytes to
// the input buffer; note this method uses the padding only, not the whole
// PKCS#7 Cryptographic Message Syntax
// - use EncryptPKCS7Length() function to compute the actual needed length
// - if IVAtBeginning is TRUE, a random Initialization Vector will be computed,
// and stored at the beginning of the output binary buffer - this IV will in
// fact contain an internal encrypted CTR, to detect any replay attack attempt
// - returns TRUE on success, FALSE if OutputLen is not correct - you should
// use EncryptPKCS7Length() to compute the exact needed number of bytes
function EncryptPKCS7Buffer(Input,Output: Pointer; InputLen,OutputLen: cardinal;
IVAtBeginning: boolean): boolean;
/// decrypt a memory buffer using a PKCS7 padding pattern
// - PKCS7 padding is described in RFC 5652 - it will trim up to 16 bytes from
// the input buffer; note this method uses the padding only, not the whole
// PKCS#7 Cryptographic Message Syntax
// - if IVAtBeginning is TRUE, the Initialization Vector will be taken
// from the beginning of the input binary buffer - this IV will in fact
// contain an internal encrypted CTR, to detect any replay attack attempt
function DecryptPKCS7Buffer(Input: Pointer; InputLen: integer;
IVAtBeginning: boolean): RawByteString;
/// initialize AEAD (authenticated-encryption with associated-data) nonce
// - i.e. setup 256-bit MAC computation during next Encrypt/Decrypt call
// - may be used e.g. for AES-GCM or our custom AES-CTR modes
// - default implementation, for a non AEAD protocol, returns false
function MACSetNonce(const aKey: THash256; aAssociated: pointer=nil;
aAssociatedLen: integer=0): boolean; virtual;
/// returns AEAD (authenticated-encryption with associated-data) MAC
/// - i.e. optional 256-bit MAC computation during last Encrypt/Decrypt call
// - may be used e.g. for AES-GCM or our custom AES-CTR modes
// - default implementation, for a non AEAD protocol, returns false
function MACGetLast(out aCRC: THash256): boolean; virtual;
/// validate if an encrypted buffer matches the stored MAC
// - expects the 256-bit MAC, as returned by MACGetLast, to be stored after
// the encrypted data
// - default implementation, for a non AEAD protocol, returns false
function MACCheckError(aEncrypted: pointer; Count: cardinal): boolean; virtual;
/// simple wrapper able to cypher/decypher any content
// - here all data variable could be text or binary
// - if IVAtBeginning is TRUE, a random Initialization Vector will be computed,
// and stored at the beginning of the output binary buffer
class function SimpleEncrypt(const Input,Key: RawByteString; Encrypt: boolean;
IVAtBeginning: boolean=false): RawByteString; overload;
/// simple wrapper able to cypher/decypher any content
// - here all data variable could be text or binary
// - if IVAtBeginning is TRUE, a random Initialization Vector will be computed,
// and stored at the beginning of the output binary buffer
class function SimpleEncrypt(const Input: RawByteString; const Key;
KeySize: integer; Encrypt: boolean; IVAtBeginning: boolean=false): RawByteString; overload;
/// associated Key Size, in bits (i.e. 128,192,256)
property KeySize: cardinal read fKeySize;
/// associated Initialization Vector
// - all modes (except ECB) do expect an IV to be supplied for chaining,
// before any encryption or decryption is performed
// - you could also use PKCS7 encoding with IVAtBeginning=true option
property IV: TAESBlock read fIV write fIV;
/// let IV detect replay attack for EncryptPKCS7 and DecryptPKCS7
// - if IVAtBeginning=true and this property is set, EncryptPKCS7 will
// store a random IV from an internal CTR, and DecryptPKCS7 will check this
// incoming IV CTR consistency, and raise an ESynCrypto exception on failure
// - leave it to its default repNoCheck if the very same TAESAbstract
// instance is expected to be used with several sources, by which the IV CTR
// will be unsynchronized
// - security warning: by design, this is NOT cautious with CBC chaining:
// you should use it only with CFB, OFB or CTR mode, since the IV sequence
// will be predictable if you know the fixed AES private key of this unit,
// but the IV sequence features uniqueness as it is generated by a good PRNG -
// see http://crypto.stackexchange.com/q/3515
property IVReplayAttackCheck: TAESIVReplayAttackCheck
read fIVReplayAttackCheck write fIVReplayAttackCheck;
/// maintains an history of previous IV, to avoid re-play attacks
// - only useful when EncryptPKCS7/DecryptPKCS7 are used with
// IVAtBeginning=true, and IVReplayAttackCheck is left to repNoCheck
property IVHistoryDepth: integer read fIVHistoryDec.Depth write SetIVHistory;
end;
/// handle AES cypher/uncypher with chaining
// - use any of the inherited implementation, corresponding to the chaining
// mode required - TAESECB, TAESCBC, TAESCFB, TAESOFB and TAESCTR classes to
// handle in ECB, CBC, CFB, OFB and CTR mode (including PKCS7-like padding)
// - this class will use AES-NI hardware instructions, if available
// - those classes are re-entrant, i.e. that you can call the Encrypt*
// or Decrypt* methods on the same instance several times
TAESAbstractSyn = class(TAESAbstract)
protected
fIn, fOut: PAESBlock;
fCV: TAESBlock;
AES: TAES;
fCount: Cardinal;
fAESInit: (initNone, initEncrypt, initDecrypt);
procedure EncryptInit;
procedure DecryptInit;
procedure TrailerBytes;
public
/// release the used instance memory and resources
// - also fill the TAES instance with zeros, for safety
destructor Destroy; override;
/// perform the AES cypher in the corresponding mode
// - this abstract method will set CV from fIV property, and fIn/fOut
// from BufIn/BufOut
procedure Encrypt(BufIn, BufOut: pointer; Count: cardinal); override;
/// perform the AES un-cypher in the corresponding mode
// - this abstract method will set CV from fIV property, and fIn/fOut
// from BufIn/BufOut
procedure Decrypt(BufIn, BufOut: pointer; Count: cardinal); override;
/// read-only access to the internal CV block, which may be have just been
// used by Encrypt/Decrypt methods
property CV: TAESBlock read fCV;
end;
/// handle AES cypher/uncypher without chaining (ECB)
// - this mode is known to be less secure than the others
// - IV property should be set to a fixed value to encode the trailing bytes
// of the buffer by a simple XOR - but you should better use the PKC7 pattern
// - this class will use AES-NI hardware instructions, if available, e.g.
// ! ECB128: 19.70ms in x86 optimized code, 6.97ms with AES-NI
TAESECB = class(TAESAbstractSyn)
public
/// perform the AES cypher in the ECB mode
procedure Encrypt(BufIn, BufOut: pointer; Count: cardinal); override;
/// perform the AES un-cypher in the ECB mode
procedure Decrypt(BufIn, BufOut: pointer; Count: cardinal); override;
end;
/// handle AES cypher/uncypher with Cipher-block chaining (CBC)
// - this class will use AES-NI hardware instructions, if available, e.g.
// ! CBC192: 24.91ms in x86 optimized code, 9.75ms with AES-NI
// - expect IV to be set before process, or IVAtBeginning=true
TAESCBC = class(TAESAbstractSyn)
public
/// perform the AES cypher in the CBC mode
procedure Encrypt(BufIn, BufOut: pointer; Count: cardinal); override;
/// perform the AES un-cypher in the CBC mode
procedure Decrypt(BufIn, BufOut: pointer; Count: cardinal); override;
end;
/// abstract parent class for chaining modes using only AES encryption
TAESAbstractEncryptOnly = class(TAESAbstractSyn)
public
/// returns this class instance, for performing the reverse process
// - return self for inherited classes of chaining modes using only Encrypt
// - warning: to be used only with IVAtBeginning=false, otherwise replay
// atacks attempts algorithm will fail the decryption
function CloneEncryptDecrypt: TAESAbstract; override;
end;
/// handle AES cypher/uncypher with Cipher feedback (CFB)
// - this class will use AES-NI hardware instructions, if available, e.g.
// ! CFB128: 22.25ms in x86 optimized code, 9.29ms with AES-NI
// - expect IV to be set before process, or IVAtBeginning=true
TAESCFB = class(TAESAbstractEncryptOnly)
public
/// perform the AES cypher in the CFB mode
procedure Encrypt(BufIn, BufOut: pointer; Count: cardinal); override;
/// perform the AES un-cypher in the CFB mode
procedure Decrypt(BufIn, BufOut: pointer; Count: cardinal); override;
end;
/// handle AES cypher/uncypher with Output feedback (OFB)
// - this class will use AES-NI hardware instructions, if available, e.g.
// ! OFB256: 27.69ms in x86 optimized code, 9.94ms with AES-NI
// - expect IV to be set before process, or IVAtBeginning=true
TAESOFB = class(TAESAbstractEncryptOnly)
public
/// perform the AES cypher in the OFB mode
procedure Encrypt(BufIn, BufOut: pointer; Count: cardinal); override;
/// perform the AES un-cypher in the OFB mode
procedure Decrypt(BufIn, BufOut: pointer; Count: cardinal); override;
end;
/// handle AES cypher/uncypher with Counter mode (CTR)
// - this class will use AES-NI hardware instructions, e.g.
// ! CTR256: 28.13ms in x86 optimized code, 10.63ms with AES-NI
// - expect IV to be set before process, or IVAtBeginning=true
TAESCTR = class(TAESAbstractEncryptOnly)
public
/// perform the AES cypher in the CTR mode
procedure Encrypt(BufIn, BufOut: pointer; Count: cardinal); override;
/// perform the AES un-cypher in the CTR mode
procedure Decrypt(BufIn, BufOut: pointer; Count: cardinal); override;
end;
TAESMAC256 = record
plain: THash128;
encrypted: THash128;
end;
/// AEAD (authenticated-encryption with associated-data) abstract class
// - perform AES encryption and on-the-fly MAC computation, i.e. computes
// a proprietary 256-bit MAC during AES cyphering, as 128-bit CRC of the
// encrypted data and 128-bit CRC of the plain data, seeded from a Key
// - the 128-bit CRC of the plain text is then encrypted using the current AES
// engine, so returned 256-bit MAC value has cryptographic level, and ensure
// data integrity, authenticity, and check against transmission errors
TAESAbstractAEAD = class(TAESAbstractEncryptOnly)
protected
fMAC, fMACKey: TAESMAC256;
public
/// initialize 256-bit MAC computation for next Encrypt/Decrypt call
// - initialize the internal fMACKey property, and returns true
// - only the plain text crc is seeded from aKey - encrypted message crc
// will use -1 as fixed seed, to avoid aKey compromission
// - should be set with a new MAC key value before each message, to avoid
// replay attacks (as called from TECDHEProtocol.SetKey)
function MACSetNonce(const aKey: THash256; aAssociated: pointer=nil;
aAssociatedLen: integer=0): boolean; override;
/// returns 256-bit MAC computed during last Encrypt/Decrypt call
// - encrypt the internal fMAC property value using the current AES cypher
// on the plain content and returns true; only the plain content CRC-128 is
// AES encrypted, to avoid reverse attacks against the known encrypted data
function MACGetLast(out aCRC: THash256): boolean; override;
/// validate if an encrypted buffer matches the stored MAC
// - expects the 256-bit MAC, as returned by MACGetLast, to be stored after
// the encrypted data
// - returns true if the 128-bit CRC of the encrypted text matches the
// supplied buffer, ignoring the 128-bit CRC of the plain data
// - since it is easy to forge such 128-bit CRC, it will only indicate
// that no transmission error occured, but won't be an integrity or
// authentication proof (which will need full Decrypt + MACGetLast)
// - may use any MACSetNonce() aAssociated value
function MACCheckError(aEncrypted: pointer; Count: cardinal): boolean; override;
end;
/// AEAD combination of AES with Cipher feedback (CFB) and 256-bit MAC
// - this class will use AES-NI and CRC32C hardware instructions, if available
// - expect IV to be set before process, or IVAtBeginning=true
TAESCFBCRC = class(TAESAbstractAEAD)
public
/// perform the AES cypher in the CFB mode, and compute a 256-bit MAC
procedure Encrypt(BufIn, BufOut: pointer; Count: cardinal); override;
/// perform the AES un-cypher in the CFB mode, and compute 256-bit MAC
procedure Decrypt(BufIn, BufOut: pointer; Count: cardinal); override;
end;
/// AEAD combination of AES with Output feedback (OFB) and 256-bit MAC
// - this class will use AES-NI and CRC32C hardware instructions, if available
// - expect IV to be set before process, or IVAtBeginning=true
TAESOFBCRC = class(TAESAbstractAEAD)
public
/// perform the AES cypher in the OFB mode, and compute a 256-bit MAC
procedure Encrypt(BufIn, BufOut: pointer; Count: cardinal); override;
/// perform the AES un-cypher in the OFB mode, and compute a 256-bit MAC
procedure Decrypt(BufIn, BufOut: pointer; Count: cardinal); override;
end;
{$ifdef USE_PROV_RSA_AES}
type
/// handle AES cypher/uncypher using Windows CryptoAPI and the
// official Microsoft AES Cryptographic Provider (PROV_RSA_AES)
// - see @http://msdn.microsoft.com/en-us/library/windows/desktop/aa386979
// - timing of our optimized asm versions, for small (<=8KB) block processing
// (similar to standard web pages or most typical JSON/XML content),
// benchmarked on a Core i7 notebook and compiled as Win32 platform:
// ! AES128 - ECB:79.33ms CBC:83.37ms CFB:80.75ms OFB:78.98ms CTR:80.45ms
// ! AES192 - ECB:91.16ms CBC:96.06ms CFB:96.45ms OFB:92.12ms CTR:93.38ms
// ! AES256 - ECB:103.22ms CBC:119.14ms CFB:111.59ms OFB:107.00ms CTR:110.13ms
// - timing of the same process, using CryptoAPI official PROV_RSA_AES provider:
// ! AES128 - ECB_API:102.88ms CBC_API:124.91ms
// ! AES192 - ECB_API:115.75ms CBC_API:129.95ms
// ! AES256 - ECB_API:139.50ms CBC_API:154.02ms
// - but the CryptoAPI does not supports AES-NI, whereas our classes do on Win32,
// with a huge speed benefit
// - under Win64, the official CryptoAPI is faster than our PUREPASCAL version,
// and the Win32 version of CryptoAPI itself:
// ! AES128 - ECB:107.95ms CBC:112.65ms CFB:109.62ms OFB:107.23ms CTR:109.42ms
// ! AES192 - ECB:130.30ms CBC:133.04ms CFB:128.78ms OFB:127.25ms CTR:130.22ms
// ! AES256 - ECB:145.33ms CBC:147.01ms CFB:148.36ms OFB:145.96ms CTR:149.67ms
// ! AES128 - ECB_API:89.64ms CBC_API:100.84ms
// ! AES192 - ECB_API:99.05ms CBC_API:105.85ms
// ! AES256 - ECB_API:107.11ms CBC_API:118.04ms
TAESAbstract_API = class(TAESAbstract)
protected
fKeyHeader: packed record
bType: byte;
bVersion: byte;
reserved: word;
aiKeyAlg: cardinal;
dwKeyLength: cardinal;
end;
fKeyHeaderKey: TAESKey; // should be just after fKeyHeader record
fKeyCryptoAPI: pointer;
fInternalMode: cardinal;
procedure InternalSetMode; virtual; abstract;
procedure EncryptDecrypt(BufIn, BufOut: pointer; Count: cardinal; DoEncrypt: boolean);
public
/// Initialize AES context for cypher
// - first method to call before using this class
// - KeySize is in bits, i.e. 128,192,256
constructor Create(const aKey; aKeySize: cardinal); override;
/// release the AES execution context
destructor Destroy; override;
/// perform the AES cypher in the ECB mode
// - if Count is not a multiple of a 16 bytes block, the IV will be used
// to XOR the trailing bytes - so it won't be compatible with our
// TAESAbstractSyn classes: you should better use PKC7 padding instead
procedure Encrypt(BufIn, BufOut: pointer; Count: cardinal); override;
/// perform the AES un-cypher in the ECB mode
// - if Count is not a multiple of a 16 bytes block, the IV will be used
// to XOR the trailing bytes - so it won't be compatible with our
// TAESAbstractSyn classes: you should better use PKC7 padding instead
procedure Decrypt(BufIn, BufOut: pointer; Count: cardinal); override;
end;
/// handle AES cypher/uncypher without chaining (ECB) using Windows CryptoAPI
TAESECB_API = class(TAESAbstract_API)
protected
/// will set fInternalMode := CRYPT_MODE_ECB
procedure InternalSetMode; override;
end;
/// handle AES cypher/uncypher Cipher-block chaining (CBC) using Windows CryptoAPI
TAESCBC_API = class(TAESAbstract_API)
protected
/// will set fInternalMode := CRYPT_MODE_CBC
procedure InternalSetMode; override;
end;
/// handle AES cypher/uncypher Cipher feedback (CFB) using Windows CryptoAPI
// - NOT TO BE USED: the current PROV_RSA_AES provider does not return
// expected values for CFB
TAESCFB_API = class(TAESAbstract_API)
protected
/// will set fInternalMode := CRYPT_MODE_CFB
procedure InternalSetMode; override;
end;
/// handle AES cypher/uncypher Output feedback (OFB) using Windows CryptoAPI
// - NOT TO BE USED: the current PROV_RSA_AES provider does not implement
// this mode, and returns a NTE_BAD_ALGID error
TAESOFB_API = class(TAESAbstract_API)
protected
/// will set fInternalMode := CRYPT_MODE_OFB
procedure InternalSetMode; override;
end;
{$endif USE_PROV_RSA_AES}
var
/// 128-bit random AES-128 entropy key for TAESAbstract.IVReplayAttackCheck
// - as used internally by AESIVCtrEncryptDecrypt() function
// - you may customize this secret for your own project, but be aware that
// it will affect all TAESAbstract instances, so should match on all ends
AESIVCTR_KEY: TBlock128 = (
$ce5d5e3e, $26506c65, $568e0092, $12cce480);
/// global shared function which may encrypt or decrypt any 128-bit block
// using AES-128 and the global AESIVCTR_KEY
procedure AESIVCtrEncryptDecrypt(const BI; var BO; DoEncrypt: boolean);
type
/// thread-safe class containing a TAES encryption/decryption engine
TAESLocked = class(TSynPersistent)
protected
fAES: TAES;
fLock: TRTLCriticalSection;
public
/// initialize the internal lock, but not the TAES instance
constructor Create; override;
/// finalize all used memory and resources
destructor Destroy; override;
end;
/// cryptographic pseudorandom number generator (CSPRNG) based on AES-256
// - use as a shared instance via TAESPRNG.Fill() overloaded class methods
// - this class is able to generate some random output by encrypting successive
// values of a counter with AES-256 and a secret key
// - the internal secret key is generated from PBKDF2 derivation of OS-supplied
// entropy using HMAC over SHA-256
// - by design, such a PRNG is as good as the cypher used - for reference, see
// https://en.wikipedia.org/wiki/Cryptographically_secure_pseudorandom_number_generator
// - it would use fast hardware AES-NI or Padlock opcodes, if available
TAESPRNG = class(TAESLocked)
protected
fCTR: THash128Rec; // we use a litle-endian CTR
fBytesSinceSeed: integer;
fSeedAfterBytes: integer;
fSeedPBKDF2Rounds: integer;
fTotalBytes: Int64;
procedure IncrementCTR; {$ifdef HASINLINE}inline;{$endif}
public
/// initialize the internal secret key, using Operating System entropy
// - entropy is gathered from the OS, using GetEntropy() method
// - you can specify how many PBKDF2_HMAC_SHA256 rounds are applied to the
// OS-gathered entropy - the higher, the better, but also the slower
// - internal private key would be re-seeded after ReseedAfterBytes
// bytes (1MB by default) are generated, using GetEntropy()
constructor Create(PBKDF2Rounds: integer = 256;
ReseedAfterBytes: integer = 1024*1024); reintroduce; virtual;
/// fill a TAESBlock with some pseudorandom data
// - could be used e.g. to compute an AES Initialization Vector (IV)
// - this method is thread-safe
procedure FillRandom(out Block: TAESBlock); overload; virtual;
/// fill a 256-bit buffer with some pseudorandom data
// - this method is thread-safe
procedure FillRandom(out Buffer: THash256); overload;
/// fill a binary buffer with some pseudorandom data
// - this method is thread-safe
procedure FillRandom(Buffer: pointer; Len: integer); overload; virtual;
/// returns a binary buffer filled with some pseudorandom data
// - this method is thread-safe
function FillRandom(Len: integer): RawByteString; overload;
/// returns a binary buffer filled with some pseudorandom data
// - this method is thread-safe
function FillRandomBytes(Len: integer): TBytes;
/// computes a random ASCII password
// - will contain uppercase/lower letters, digits and $.:()?%!-+*/@#
// excluding ;,= to allow direct use in CSV content
function RandomPassword(Len: integer): RawUTF8;
/// would force the internal generator to re-seed its private key
// - avoid potential attacks on backward or forward security
// - would be called by FillRandom() methods, according to SeedAfterBytes
// - this method is thread-safe
procedure Seed; virtual;
/// retrieve some entropy bytes from the Operating System
// - entropy comes from CryptGenRandom API on Windows, and /dev/urandom or
// /dev/random on Linux/POSIX
// - depending on the system, entropy may not be true randomness: if you need
// some truly random values, use TAESPRNG.Main.FillRandom() or TAESPRNG.Fill()
// methods, NOT this class function (which will be much slower, BTW)
class function GetEntropy(Len: integer): RawByteString; virtual;
/// returns a shared instance of a TAESPRNG instance
// - if you need to generate some random content, just call the
// TAESPRNG.Main.FillRandom() overloaded methods, or directly TAESPRNG.Fill()
class function Main: TAESPRNG;
/// just a wrapper around TAESPRNG.Main.FillRandom() function
// - this method is thread-safe, but you may use your own TAESPRNG instance
// if you need some custom entropy level
class procedure Fill(Buffer: pointer; Len: integer); overload;
{$ifdef HASINLINE}inline;{$endif}
/// just a wrapper around TAESPRNG.Main.FillRandom() function
// - this method is thread-safe, but you may use your own TAESPRNG instance
// if you need some custom entropy level
class procedure Fill(out Block: TAESBlock); overload;
{$ifdef HASINLINE}inline;{$endif}
/// just a wrapper around TAESPRNG.Main.FillRandom() function
// - this method is thread-safe, but you may use your own TAESPRNG instance
// if you need some custom entropy level
class function Fill(Len: integer): RawByteString; overload;
{$ifdef HASINLINE}inline;{$endif}
/// just a wrapper around TAESPRNG.Main.FillRandomBytes() function
// - this method is thread-safe, but you may use your own TAESPRNG instance
// if you need some custom entropy level
class function Bytes(Len: integer): TBytes;
{$ifdef HASINLINE}inline;{$endif}
/// create an anti-forensic representation of a key for safe storage
// - a binary buffer will be split into StripesCount items, ready to be
// saved on disk; returned length is BufferBytes*(StripesCount+1) bytes
// - AFSplit supports secure data destruction crucial for secure on-disk
// key management. The key idea is to bloat information and therefore
// improve the chance of destroying a single bit of it. The information
// is bloated in such a way, that a single missing bit causes the original
// information become unrecoverable.
// - this implementation uses SHA-256 as diffusion element, and the current
// TAESPRNG instance to gather randomness
// - for reference, see TKS1 as used for LUKS and defined in
// @https://gitlab.com/cryptsetup/cryptsetup/wikis/TKS1-draft.pdf
function AFSplit(const Buffer; BufferBytes, StripesCount: integer): RawByteString;
/// retrieve a key from its anti-forensic representation
// - is the reverse function of AFSplit() method
// - returns TRUE if the input buffer matches BufferBytes value
class function AFUnsplit(const Split: RawByteString;
out Buffer; BufferBytes: integer): boolean; overload;
/// retrieve a key from its anti-forensic representation
// - is the reverse function of AFSplit() method
// - returns the un-splitted binary content
// - returns '' if StripesCount is incorrect
class function AFUnsplit(const Split: RawByteString;
StripesCount: integer): RawByteString; overload;
/// after how many generated bytes Seed method would be called
// - default is 1 MB
property SeedAfterBytes: integer read fSeedAfterBytes;
/// how many PBKDF2_HMAC_SHA256 count is applied by Seed to the entropy
// - default is 256 rounds, which is enough for entropy gathering
property SeedPBKDF2Rounds: integer read fSeedPBKDF2Rounds;