Re: problem with encryption
David Beck wrote: I finally resolved the issue with PHP and Rev encryption and I wanted to share the resolution with the list. I was able to get aes-128 bit working - 256 is still a mystery. (I think there is a problem with Rev only looking at the first 16 bytes of the IV value for 256 bit, as it appears bytes after #16 do not affect the resulting encrypted value with Rev. I will log this as a bug.) ...snip... Hope this is helpful to somebody in the future! Thank you for posting that David. I've saved it for future reference. :-) Martin Baxter ___ use-revolution mailing list use-revolution@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-revolution
Re: problem with encryption
I finally resolved the issue with PHP and Rev encryption and I wanted to
share the resolution with the list. I was able to get aes-128 bit
working - 256 is still a mystery. (I think there is a problem with Rev
only looking at the first 16 bytes of the IV value for 256 bit, as it
appears bytes after #16 do not affect the resulting encrypted value with
Rev. I will log this as a bug.)
The problem is that when the data being encrypted was not 16-byte
aligned, meaning that the length of the data was not evenly divisible by
16, the Rev and PHP mcrypt libraries would encrypt and dycrypt the
values differently. I don't know if this is a bug in the mcrypt library
or in Rev or a general lack of specification but that was the problem.
Also PHP throws in some extra null characters when decrypting even
16-byte aligned strings at the end, so what I am doing is including the
length of the original data so that after the decryption is done with
PHP just that data is used as the final decrypted string.
So to put all of this is technical terms, here is the Rev script to
encrypt the data:
On encryptData theKey, @data
-- first generate a random 16 byte IV value
put getRandomSalt() into theIV
put binaryEncode( "N", the number of chars in data ) into dataSize
-- pad to size 16
repeat while the number of chars in data mod 16 is not 0
put numToChar( 0 ) after data
end repeat
encrypt data using "aes-128-cbc" with key theKey and iv theIV
if the result is not empty then
ci_NoteAlert "Error while encrypting:" && the result
exit to top
end if
put dataSize & theIV & it into data
return data
end encryptData
and the php to decode a chunk of data returned by the above script looks
like:
function decryptData( $theKey, &$data )
{
$dataLen = substr( $data, 0, 4 );
$dataLenArr = unpack( "N*", $dataLen );
$dataLen = $dataLenArr[1];
$data = substr( $data, 4 );
$iv = substr( $data, 0, 16 );
$data = substr( $data, 16 );
$td = mcrypt_module_open( MCRYPT_RIJNDAEL_128, '', 'cbc', '' );
mcrypt_generic_init( $td, $theKey, $iv );
$data = mdecrypt_generic( $td, $data );
mcrypt_generic_deinit($td);
mcrypt_module_close($td);
$data = substr( $data, 0, $dataLen );
}
Hope this is helpful to somebody in the future!
David
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Re: problem with encryption
Theirry - Sorry about the confusion. The IV value was different (I've tried this many times with many IVs and must have slipped up) but even when the correction is made the two strings produced are still different. I can't produce the same string with any of the ciphers that both Rev and PHP support and I've tried them all (aes, blowfish, cast, rc2). Could there be something that Rev or PHP (the mcrypt library) is doing to the data or key / iv (for example padding) that the other is not? Has anybody been able to get Rev and php encryption working together? Thanks, David Hmm, possibly a typo, but are you aware your IV value is a bit different ( 89 missing in the middle ) ? HTH Thierry ___ use-revolution mailing list use-revolution@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-revolution
Re: problem with encryption
Le 1 juin 07 à 15:18, David Beck a écrit : Despite all my efforts I can not ecnrypt a string the same way with Rev and php. The following rev code; encrypt "hello" using "aes-128-cbc" with key "0123456789abcdef" and iv "01234567012345" Hmm, possibly a typo, but are you aware your IV value is a bit different ( 89 missing in the middle ) ? HTH Thierry mcrypt_generic_init( $td, '0123456789abcdef', '0123456789012345' ); $data = mcrypt_generic( $td, 'hello' ); mcrypt_generic_deinit($td); mcrypt_module_close($td); echo( $data ); should be exactly equivilent, but produces: Ý~Õ xëCàñTš6 Does anybody know why these two are producing two different strings or has anybody been able to get rev and php successfully "talking the same encryption language"? I can not get encryption / decryption to work between platforms. I have tried many different ciphers all with a ___ use-revolution mailing list use-revolution@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-revolution
problem with encryption
Despite all my efforts I can not ecnrypt a string the same way with Rev and php. The following rev code; encrypt "hello" using "aes-128-cbc" with key "0123456789abcdef" and iv "01234567012345" put it produces: å U[·á$,^Ám¡u The php code: $td = mcrypt_module_open( MCRYPT_RIJNDAEL_128, '', 'cbc', '' ); mcrypt_generic_init( $td, '0123456789abcdef', '0123456789012345' ); $data = mcrypt_generic( $td, 'hello' ); mcrypt_generic_deinit($td); mcrypt_module_close($td); echo( $data ); should be exactly equivilent, but produces: Ý~Õ xëCàñT6 Does anybody know why these two are producing two different strings or has anybody been able to get rev and php successfully "talking the same encryption language"? I can not get encryption / decryption to work between platforms. I have tried many different ciphers all with a similar result. Thanks very much for any help, David ___ use-revolution mailing list use-revolution@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-revolution
