#FEATURE by cg
class: Socket class
added: #newTCPclientToHost:port:domain:domainOrder:withTimeout:
changed: #newTCPclientToHost:port:domain:withTimeout:
"
COPYRIGHT (c) 2018 by eXept Software AG
All Rights Reserved
This software is furnished under a license and may be used
only in accordance with the terms of that license and with the
inclusion of the above copyright notice. This software may not
be provided or otherwise made available to, or used by, any
other person. No title to or ownership of the software is
hereby transferred.
"
"{ Package: 'stx:libbasic2' }"
"{ NameSpace: Smalltalk }"
HashStream subclass:#CRCStream
instanceVariableNames:'crc generatorPolynom crcTable initValue xorOut'
classVariableNames:''
poolDictionaries:''
category:'System-Crypt-Hashing'
!
CRCStream class instanceVariableNames:'crcTables'
"
No other class instance variables are inherited by this class.
"
!
!CRCStream class methodsFor:'documentation'!
copyright
"
COPYRIGHT (c) 2018 by eXept Software AG
All Rights Reserved
This software is furnished under a license and may be used
only in accordance with the terms of that license and with the
inclusion of the above copyright notice. This software may not
be provided or otherwise made available to, or used by, any
other person. No title to or ownership of the software is
hereby transferred.
"
!
documentation
"
abstract superclass of crc streams;
refactored from original crc32 stream.
For details, see https://en.wikipedia.org/wiki/Cyclic_redundancy_check
Only use CRC to protect against communication errors;
DO NOT use CRC for cryptography, authentication, security, etc.
- use secure hashes for those instead.
[parameters:]
polynomials:
CRC_POLY_16 0xA001
CRC_POLY_32 0xEDB88320L
CRC_POLY_CCITT 0x1021
CRC_POLY_DNP 0xA6BC
CRC_POLY_KERMIT 0x8408
start values:
CRC_START_8 0x00
CRC_START_16 0x0000
CRC_START_MODBUS 0xFFFF
CRC_START_XMODEM 0x0000
CRC_START_CCITT_1D0F 0x1D0F
CRC_START_CCITT_FFFF 0xFFFF
CRC_START_KERMIT 0x0000
CRC_START_SICK 0x0000
CRC_START_DNP 0x0000
CRC_START_32 0xFFFFFFFF
"
! !
!CRCStream class methodsFor:'initialization'!
crcTableFor:generatorPolynomInteger
"construct the polynom-specific lookup table"
|crcTable|
"/ CRC8Stream flushCrcTables
"/ CRC8Stream crcTableFor:(16r1D bitReversed8)
crcTables isNil ifTrue:[
crcTables := Dictionary new
].
crcTable := (crcTables at:generatorPolynomInteger ifAbsent:nil).
crcTable isNil ifTrue:[
"/ for crc16 and crc8, we waste some memory
"/ (could use WordArray or ByteArray);
"/ but that would need three writeBytes implementations.
"/ Not worth the saving.
crcTable := IntegerArray new:256.
"/ least-sign. bit towards most significant bit...
0 to:255 do:[:count| |i|
i := count.
8 timesRepeat:[
(i bitTest:1) ifTrue:[
i := generatorPolynomInteger bitXor:(i bitShift:-1)
] ifFalse:[
i := i bitShift:-1
]
].
crcTable at:count+1 put:i.
].
crcTables at:generatorPolynomInteger put:crcTable.
].
^ crcTable.
"Created: / 16-03-2019 / 20:53:51 / Claus Gittinger"
"Modified: / 24-03-2019 / 12:38:12 / Claus Gittinger"
!
flushCrcTables
crcTables := nil.
"
CRC16Stream flushCrcTables
CRC32Stream flushCrcTables
"
"Created: / 16-03-2019 / 23:41:19 / Claus Gittinger"
! !
!CRCStream class methodsFor:'instance creation'!
generatorPolynom:anLSBInteger
"notice, in literature, the generator polynom is usually specified as an MSB number"
^ self basicNew
generatorPolynom:anLSBInteger
"
self assert:((self generatorPolynom:16r82F63B78)
nextPut:'123456789';
hashValue) = 16rE3069283
"
"Modified (format): / 17-03-2019 / 14:03:42 / Claus Gittinger"
!
generatorPolynom:anLSBInteger initValue:initValue
"notice, in literature, the generator polynom is usually specified as an MSB number"
^ self basicNew
generatorPolynom:anLSBInteger
initValue:initValue
"
self assert:((self generatorPolynom:16r82F63B78)
nextPut:'123456789';
hashValue) = 16rE3069283
"
"Created: / 16-03-2019 / 21:15:54 / Claus Gittinger"
"Modified (format): / 17-03-2019 / 14:03:37 / Claus Gittinger"
!
generatorPolynom:anLSBInteger initValue:initValue xorOut:xorOut
"notice, in literature, the generator polynom is usually specified as an MSB number"
^ self basicNew
generatorPolynom:anLSBInteger
initValue:initValue xorOut:xorOut
"
self assert:((self generatorPolynom:16r82F63B78)
nextPut:'123456789';
hashValue) = 16rE3069283
"
"Created: / 16-03-2019 / 21:16:05 / Claus Gittinger"
"Modified (format): / 17-03-2019 / 14:03:30 / Claus Gittinger"
! !
!CRCStream methodsFor:'accessing'!
generatorPolynom
"answer the generator polynom (LSB)"
^ generatorPolynom
"Modified (comment): / 16-03-2019 / 20:58:10 / Claus Gittinger"
!
initValue
"answer the init value"
^ initValue ? 0
"Created: / 16-03-2019 / 21:05:04 / Claus Gittinger"
!
xorOut
"answer the xorOut value"
^ xorOut ? 16rFFFFFFFF
"Created: / 16-03-2019 / 21:16:23 / Claus Gittinger"
! !
!CRCStream methodsFor:'initialization'!
generatorPolynom:polyLSB initValue:initValueArg xorOut:xorOutArg
"set the generator polynom for this instance.
And set start and xorOut.
Computes the crcTable for this polynom.
Notice the bit order is LSB"
generatorPolynom := polyLSB.
crc := initValue := initValueArg.
xorOut := xorOutArg.
crcTable := self class crcTableFor:generatorPolynom.
"Created: / 16-03-2019 / 21:17:12 / Claus Gittinger"
"Modified (comment): / 17-03-2019 / 12:25:11 / Claus Gittinger"
!
reset
"reset the current crc value"
crc := initValue.
"Created: / 16-03-2019 / 21:25:27 / Claus Gittinger"
! !
!CRCStream methodsFor:'queries'!
hashValue
"return the computed CRC"
^ crc bitXor:xorOut.
"Modified: / 16-03-2019 / 21:27:59 / Claus Gittinger"
! !
!CRCStream methodsFor:'writing'!
nextPutBytes:count from:anObject startingAt:start
"add the hash of anObject to the computed hash so far."
%{
int len, offs;
// fetch first - check later
len = __intVal(count);
offs = __intVal(start) - 1;
if (__bothSmallInteger(count, start)) {
int objSize;
unsigned char *extPtr;
// the most common first
if (__isStringLike(anObject)) {
objSize = __stringSize(anObject);
extPtr = (unsigned char *)__stringVal(anObject);
} else if (__isByteArray(anObject)) {
objSize = __byteArraySize(anObject);
extPtr = (unsigned char *)__byteArrayVal(anObject);
} else if (__isExternalBytesLike(anObject)) {
OBJ sz = __externalBytesSize(anObject);
extPtr = (unsigned char *)__externalBytesAddress(anObject);
if (__isSmallInteger(sz)) {
objSize = __intVal(sz);
} else {
objSize = 0; /* unknown */
}
} else {
int nInstVars, nInstBytes;
OBJ oClass = __Class(anObject);
switch (__intVal(__ClassInstPtr(oClass)->c_flags) & ARRAYMASK) {
case BYTEARRAY:
case WORDARRAY:
case LONGARRAY:
case SWORDARRAY:
case SLONGARRAY:
case FLOATARRAY:
case DOUBLEARRAY:
break;
default:
goto bad;
}
nInstVars = __intVal(__ClassInstPtr(oClass)->c_ninstvars);
nInstBytes = __OBJS2BYTES__(nInstVars);
// nInstBytes is the number of bytes occupied by pointer instance variables
// subtract from size and add to byte-pointer
objSize = __qSize(anObject) - OHDR_SIZE - nInstBytes;
extPtr = (unsigned char *)__byteArrayVal(anObject)+nInstBytes;
}
if ((offs >= 0) && (len >= 0) && (objSize >= (len + offs))) {
unsigned int _crc;
unsigned int *_crcTable = __integerArrayVal( __INST(crcTable) );
unsigned char *cp = extPtr+offs;
unsigned int n = len;
_crc = (unsigned int) (__intVal( __INST(crc) ));
#if __POINTER_SIZE__ != 8
if (!__isSmallInteger(__INST(crc))) {
_crc = __unsignedLongIntVal( __INST(crc) );
}
#endif
#ifdef __LSBFIRST__
# if __POINTER_SIZE__ == 8
if (((unsigned INT)cp & 7) == 0) {
// longword aligned
for ( ; n >= 8 ; n -= 8, cp += 8) {
unsigned INT lWord;
unsigned char _idx;
lWord = ((unsigned INT *)cp)[0];
_idx = (_crc ^ lWord) & 0xFF;
_crc = _crcTable[_idx] ^ (_crc >> 8);
_idx = (_crc ^ (lWord>>8)) & 0xFF;
_crc = _crcTable[_idx] ^ (_crc >> 8);
_idx = (_crc ^ (lWord>>16)) & 0xFF;
_crc = _crcTable[_idx] ^ (_crc >> 8);
_idx = (_crc ^ (lWord>>24)) & 0xFF;
_crc = _crcTable[_idx] ^ (_crc >> 8);
_idx = (_crc ^ (lWord>>32)) & 0xFF;
_crc = _crcTable[_idx] ^ (_crc >> 8);
_idx = (_crc ^ (lWord>>40)) & 0xFF;
_crc = _crcTable[_idx] ^ (_crc >> 8);
_idx = (_crc ^ (lWord>>48)) & 0xFF;
_crc = _crcTable[_idx] ^ (_crc >> 8);
_idx = (_crc ^ (lWord>>56)) & 0xFF;
_crc = _crcTable[_idx] ^ (_crc >> 8);
}
}
# endif // __POINTER_SIZE__ == 8
if (((unsigned INT)cp & 3) == 0) {
// word aligned
for ( ; n >= 4 ; n -= 4, cp += 4) {
unsigned int word;
unsigned char _idx;
word = ((unsigned int *)cp)[0];
_idx = (_crc ^ word) & 0xFF;
_crc = _crcTable[_idx] ^ (_crc >> 8);
_idx = (_crc ^ (word>>8)) & 0xFF;
_crc = _crcTable[_idx] ^ (_crc >> 8);
_idx = (_crc ^ (word>>16)) & 0xFF;
_crc = _crcTable[_idx] ^ (_crc >> 8);
_idx = (_crc ^ (word>>24)) & 0xFF;
_crc = _crcTable[_idx] ^ (_crc >> 8);
}
}
#endif // LSBFIRST
for ( ; n >= 4 ; n -= 4, cp += 4) {
unsigned char _idx;
_idx = (_crc ^ cp[0]) & 0xFF;
_crc = _crcTable[_idx] ^ (_crc >> 8);
_idx = (_crc ^ cp[1]) & 0xFF;
_crc = _crcTable[_idx] ^ (_crc >> 8);
_idx = (_crc ^ cp[2]) & 0xFF;
_crc = _crcTable[_idx] ^ (_crc >> 8);
_idx = (_crc ^ cp[3]) & 0xFF;
_crc = _crcTable[_idx] ^ (_crc >> 8);
}
while (n-- > 0) {
unsigned char _idx = (_crc ^ *cp++) & 0xFF;
_crc = _crcTable[_idx] ^ (_crc >> 8);
}
#if __POINTER_SIZE__ == 8
__INST(crc) = __MKSMALLINT(_crc);
#else
if (_crc <= _MAX_INT) {
__INST(crc) = __MKSMALLINT(_crc);
} else {
// this code fails with gcc 4.7.2:
// __INST(crc) = __MKUINT(_crc); __STORESELF(crc);
OBJ temp = __MKUINT(_crc);
__INST(crc) = temp; __STORESELF(crc);
}
#endif
RETURN (count);
}
}
bad: ;
%}.
ArgumentError raise
"Created: / 09-01-2012 / 16:48:35 / cg"
"Modified: / 06-06-2019 / 23:16:48 / Claus Gittinger"
! !
!CRCStream class methodsFor:'documentation'!
version_CVS
^ '$Header$'
! !