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• How to find Key and IV value from .Net to PHP

  - by PHP-Prabhu

  Can any one please let me know is there any way to find a solution for the below stuffs. I need to find out the KEY and IV value from the below byte array. the byte array in .net and this has to be convert into KEY(string) and IV(string) via PHP. private static readonly byte[] Key = { 0xda, 0x3c, 0x35, 0x6f, 0xbd, 0xd, 0x87, 0xf0, 0x9a, 0x7, 0x6d, 0xab, 0x7e, 0x82, 0x36, 0xa, 0x1a, 0x5a, 0x77, 0xfe, 0x74, 0xf3, 0x7f, 0xa8, 0xaa, 0x4, 0x11, 0x46, 0x6b, 0x2d, 0x48, 0xa1 }; private static readonly byte[] IV = { 0x6d, 0x2d, 0xf5, 0x34, 0xc7, 0x60, 0xc5, 0x33, 0xe2, 0xa3, 0xd7, 0xc3, 0xf3, 0x39, 0xf2, 0x16 };

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• RijndaelManaged: IV Generation?

  - by cam

  I want to implement the most secure, and most reliable form of symmetric key cryptography in my application. The user should input a password to encrypt/decrypt, and that's all. For RijndaelManaged, one must enter a key and an IV. I'm not sure how to address the situation. Right now, I have the entered password being hashed by SHA256 and then being used as the key for the Rijndael. What do I use for the IV? Another password?

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• Silverlight and Encryption, how to store/generate they key/iv pair?

  - by cmaduro

  I have a Silverlight app that connects to a php webservice. I want to encrypt the communication between the webservice and the Silverlight client. I'm not relying on SSL. I'm encrypting/decrypting the POST string myself using AES 256bit Key and IV. The big questions then are: How do I generate a random unique key/iv pair in PHP. How do I share this key/iv pair between the web service and silverlight client in a secure way. It seems impossible without having some kind of hard coded key or iv on the client. Which would compromise security. This is a public website, there are no logins. Just the requirement of secure communication. I can hard code the seed for the key/iv (which is hashed with SHA256 with a time stamp salt and then assigned as the key or iv) in PHP source code, that's on the server so that is pretty safe. However on the client the seed for the key/iv pair would be visible, if it is hard coded. Further more using a time stamp as the basis for uniqueness/randomness is definitely not ok, since timestamps are predictable. It does however provide a common factor between the C# code and the PHP code. The only other option that I can think of would be to have a 3rd service involved that provides the key/iv to the Silverlight client, as well as the php webservice. This of course start the cycle anew, with the question of how to store the credentials for accessing the key/iv distribution service on the Silverlight client. Sounds like the solution is then asymmetric encryption, since sensitive data will be viewed only on the administrative back end of the website. Unfortunately Silverlight has no asymmetric encryption classes. The solution? Roll my own Diffie-Hellman key exchange! Plug that key into AES256!

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• Why is using a Non-Random IV with CBC Mode a vulnerability?

  - by The Rook

  I understand the purpose of an IV. Specifically in CBC mode this insures that the first block of of 2 messages encrypted with the same key will never be identical. But why is it a vulnerability if the IV's are sequential? According to CWE-329 NON-Random IV's allow for the possibility of a dictionary attack. I know that in practice protocols like WEP make no effort to hide the IV. If the attacker has the IV and a cipher text message then this opens the door for a dictionary attack against the key. I don't see how a random iv changes this. (I know the attacks against wep are more complex than this.) What security advantage does a randomized iv have? Is this still a problem with an "Ideal Block Cipher"? (A perfectly secure block cipher with no possible weaknesses.)

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• gnuplot - multiple lines with different x ranges

  - by Aly

  Hi, I am using gnuplot to try and plot several lines but each have different x ranges. I am running the following script: # gnuplot script for 'omarConf2EvONLY-vs-everyone-gta-lag-lpas-omarConf1-random-tag-tpas.dat' plot "omarConf2EvONLY-vs-everyone-gta-lag-lpas-omarConf1-random-tag-tpas.dat" using 1:2 with lines title '1' replot "omarConf2EvONLY-vs-everyone-gta-lag-lpas-omarConf1-random-tag-tpas.dat" using 1:3 with lines title '2' replot "omarConf2EvONLY-vs-everyone-gta-lag-lpas-omarConf1-random-tag-tpas.dat" using 1:4 with lines title '3' replot "omarConf2EvONLY-vs-everyone-gta-lag-lpas-omarConf1-random-tag-tpas.dat" using 1:5 with lines title '4' replot "omarConf2EvONLY-vs-everyone-gta-lag-lpas-omarConf1-random-tag-tpas.dat" using 1:6 with lines title '5' replot "omarConf2EvONLY-vs-everyone-gta-lag-lpas-omarConf1-random-tag-tpas.dat" using 1:7 with lines title '6' replot "omarConf2EvONLY-vs-everyone-gta-lag-lpas-omarConf1-random-tag-tpas.dat" using 1:8 with lines title '7' set terminal png size 800,600 set output "omar_vs_everyone-EVONLY.png" replot and the .dat file is just a file with columns such as: 1 0.5 0.5 0.1 2 0.6 1.3 0.8 3 0.7 0.32 4 0.7 0.35 5 1.3 4.32 6 1.67 notice that the columns have different lengths as each line has different x ranges. The problem I have is that it plots funny as shown below:

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• How do you save and retrieve a Key/IV pair securely?

  - by Shawn Steward

  I'm using VB.Net's RijndaelManaged (RM) to encrypt files, using the RM.GenerateKey and RM.GenerateIV methods to generate the Key and IV and encrypting the file using the CryptoStream class. I'm planning on saving this Key and IV to a file and want to make sure I'm doing it the right way. I am combining the IV+Key, and encrypting that with my RSA Public key and writing it out to a file. Then, to decrypt I use the RSA Private key on this file to get the IV+Key, split them up and set RM.Key and RM.IV to these values and run the decryptor. Is this the best method to accomplish this, or is there a preferred method for saving the IV & Key? Also, what's the best way to construct and deconstruct the byte array? I used the .Concat method to join them together and that seems to work well but I can't seem to find something as easy to deconstruct it. I played with the .Take method that takes the first x # of bytes and it works for the first part but can't find anything that gets the rest of it.

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• Why can't we just use a hash of passphrase as the encryption key (and IV) with symmetric encryption algorithms?

  - by TX_

  Inspired by my previous question, now I have a very interesting idea: Do you really ever need to use Rfc2898DeriveBytes or similar classes to "securely derive" the encryption key and initialization vector from the passphrase string, or will just a simple hash of that string work equally well as a key/IV, when encrypting the data with symmetric algorithm (e.g. AES, DES, etc.)? I see tons of AES encryption code snippets, where Rfc2898DeriveBytes class is used to derive the encryption key and initialization vector (IV) from the password string. It is assumed that one should use a random salt and a shitload of iterations to derive secure enough key/IV for the encryption. While deriving bytes from password string using this method is quite useful in some scenarios, I think that's not applicable when encrypting data with symmetric algorithms! Here is why: using salt makes sense when there is a possibility to build precalculated rainbow tables, and when attacker gets his hands on hash he looks up the original password as a result. But... with symmetric data encryption, I think this is not required, as the hash of password string, or the encryption key, is never stored anywhere. So, if we just get the SHA1 hash of password, and use it as the encryption key/IV, isn't that going to be equally secure? What is the purpose of using Rfc2898DeriveBytes class to generate key/IV from password string (which is a very very performance-intensive operation), when we could just use a SHA1 (or any other) hash of that password? Hash would result in random bit distribution in a key (as opposed to using string bytes directly). And attacker would have to brute-force the whole range of key (e.g. if key length is 256bit he would have to try 2^256 combinations) anyway. So either I'm wrong in a dangerous way, or all those samples of AES encryption (including many upvoted answers here at SO), etc. that use Rfc2898DeriveBytes method to generate encryption key and IV are just wrong.

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• encfs error while decoding the data

  - by migrator

  I have installed encfs and started using it to secure all my personal & office data and it was working absolutely fine until 2 hours back. The setup is like this. I have a folder in Copy folder called OfficeData which gets synchronized with my Copy folder When I login into the system I use the command encfs ~/Copy/OfficeData ~/Documents/OfficeData Once my work is over I dismount with the command fusermount -u ~/Documents/OfficeData All this data get synchronized with my desktop and with my mobile phone (as a backup) Today when I mounted, the folder got mounted by no directories and files present in that folder. I was worried and read man encfs which gave me to run the command encfs -v -f ~/Copy/OfficeData ~/Documents/OfficeData 2> encfs-OfficeData-report.txt. The below is the output of the file encfs-OfficeData-report.txt. The directory "/home/sri/Documents/OfficeData" does not exist. Should it be created? (y,n) 13:16:26 (main.cpp:523) Root directory: /home/sri/Copy/OfficeData/ 13:16:26 (main.cpp:524) Fuse arguments: (fg) (threaded) (keyCheck) encfs /home/sri/Documents/OfficeData -f -s -o use_ino -o default_permissions 13:16:26 (FileUtils.cpp:177) version = 20 13:16:26 (FileUtils.cpp:181) found new serialization format 13:16:26 (FileUtils.cpp:199) subVersion = 20100713 13:16:26 (Interface.cpp:165) checking if ssl/aes(3:0:2) implements ssl/aes(3:0:0) 13:16:26 (SSL_Cipher.cpp:370) allocated cipher ssl/aes, keySize 32, ivlength 16 13:16:26 (Interface.cpp:165) checking if ssl/aes(3:0:2) implements ssl/aes(3:0:0) 13:16:26 (SSL_Cipher.cpp:370) allocated cipher ssl/aes, keySize 32, ivlength 16 13:16:26 (FileUtils.cpp:1620) useStdin: 0 13:16:46 (Interface.cpp:165) checking if ssl/aes(3:0:2) implements ssl/aes(3:0:0) 13:16:46 (SSL_Cipher.cpp:370) allocated cipher ssl/aes, keySize 32, ivlength 16 13:16:49 (FileUtils.cpp:1628) cipher key size = 52 13:16:49 (Interface.cpp:165) checking if nameio/block(3:0:1) implements nameio/block(3:0:0) 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (RawFileIO.cpp:191) getAttr error on /home/sri/Copy/OfficeData/UWbT-M-UKk1JpvNfN5uvOhGn: No such file or directory 13:16:49 (CipherFileIO.cpp:105) in setIV, current IV = 0, new IV = 4188221457101129840, fileIV = 0 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/UWbT-M-UKk1JpvNfN5uvOhGn 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/UWbT-M-UKk1JpvNfN5uvOhGn 13:16:49 (RawFileIO.cpp:191) getAttr error on /home/sri/Copy/OfficeData/UWbT-M-UKk1JpvNfN5uvOhGn: No such file or directory 13:16:49 (encfs.cpp:138) getattr error: No such file or directory 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (RawFileIO.cpp:191) getAttr error on /home/sri/Copy/OfficeData/o94olxB3orqarqyFviHKZ,ZF: No such file or directory 13:16:49 (CipherFileIO.cpp:105) in setIV, current IV = 0, new IV = 16725694203599486310, fileIV = 0 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/o94olxB3orqarqyFviHKZ,ZF 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/o94olxB3orqarqyFviHKZ,ZF 13:16:49 (RawFileIO.cpp:191) getAttr error on /home/sri/Copy/OfficeData/o94olxB3orqarqyFviHKZ,ZF: No such file or directory 13:16:49 (encfs.cpp:138) getattr error: No such file or directory 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (RawFileIO.cpp:191) getAttr error on /home/sri/Copy/OfficeData/tVglci2rgp9o8qE-m9AvX6JNj1lQs-ER0OvnxfOb30Z,3,: No such file or directory 13:16:49 (CipherFileIO.cpp:105) in setIV, current IV = 0, new IV = 1354483141023495884, fileIV = 0 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/tVglci2rgp9o8qE-m9AvX6JNj1lQs-ER0OvnxfOb30Z,3, 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/tVglci2rgp9o8qE-m9AvX6JNj1lQs-ER0OvnxfOb30Z,3, 13:16:49 (RawFileIO.cpp:191) getAttr error on /home/sri/Copy/OfficeData/tVglci2rgp9o8qE-m9AvX6JNj1lQs-ER0OvnxfOb30Z,3,: No such file or directory 13:16:49 (encfs.cpp:138) getattr error: No such file or directory 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (RawFileIO.cpp:191) getAttr error on /home/sri/Copy/OfficeData/r1KIEqVkz-,7-6CobavHCSNn: No such file or directory 13:16:49 (CipherFileIO.cpp:105) in setIV, current IV = 0, new IV = 16720606331386655431, fileIV = 0 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/r1KIEqVkz-,7-6CobavHCSNn 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/r1KIEqVkz-,7-6CobavHCSNn 13:16:49 (RawFileIO.cpp:191) getAttr error on /home/sri/Copy/OfficeData/r1KIEqVkz-,7-6CobavHCSNn: No such file or directory 13:16:49 (encfs.cpp:138) getattr error: No such file or directory 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:16:49 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:16:49 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:16:49 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:16:49 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:16:49 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:16:49 (FileNode.cpp:127) calling setIV on (null) 13:16:49 (RawFileIO.cpp:191) getAttr error on /home/sri/Copy/OfficeData/r1KIEqVkz-,7-6CobavHCSNn: No such file or directory 13:16:49 (CipherFileIO.cpp:105) in setIV, current IV = 0, new IV = 16720606331386655431, fileIV = 0 13:16:49 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/r1KIEqVkz-,7-6CobavHCSNn 13:16:49 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/r1KIEqVkz-,7-6CobavHCSNn 13:16:49 (RawFileIO.cpp:191) getAttr error on /home/sri/Copy/OfficeData/r1KIEqVkz-,7-6CobavHCSNn: No such file or directory 13:16:49 (encfs.cpp:138) getattr error: No such file or directory 13:19:31 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:19:31 (FileNode.cpp:127) calling setIV on (null) 13:19:31 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/ 13:19:31 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/ 13:19:31 (encfs.cpp:685) doing statfs of /home/sri/Copy/OfficeData 13:19:32 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:19:32 (FileNode.cpp:127) calling setIV on (null) 13:19:32 (RawFileIO.cpp:191) getAttr error on /home/sri/Copy/OfficeData/LuT8R,DlpRnNH9b,fjWiKHKc: No such file or directory 13:19:32 (CipherFileIO.cpp:105) in setIV, current IV = 0, new IV = 13735228085838055696, fileIV = 0 13:19:32 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/LuT8R,DlpRnNH9b,fjWiKHKc 13:19:32 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/LuT8R,DlpRnNH9b,fjWiKHKc 13:19:32 (RawFileIO.cpp:191) getAttr error on /home/sri/Copy/OfficeData/LuT8R,DlpRnNH9b,fjWiKHKc: No such file or directory 13:19:32 (encfs.cpp:138) getattr error: No such file or directory 13:19:32 (encfs.cpp:685) doing statfs of /home/sri/Copy/OfficeData 13:19:32 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:19:32 (FileNode.cpp:127) calling setIV on (null) 13:19:32 (RawFileIO.cpp:191) getAttr error on /home/sri/Copy/OfficeData/UWbT-M-UKk1JpvNfN5uvOhGn: No such file or directory 13:19:32 (CipherFileIO.cpp:105) in setIV, current IV = 0, new IV = 4188221457101129840, fileIV = 0 13:19:32 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/UWbT-M-UKk1JpvNfN5uvOhGn 13:19:32 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/UWbT-M-UKk1JpvNfN5uvOhGn 13:19:32 (RawFileIO.cpp:191) getAttr error on /home/sri/Copy/OfficeData/UWbT-M-UKk1JpvNfN5uvOhGn: No such file or directory 13:19:32 (encfs.cpp:138) getattr error: No such file or directory 13:19:32 (MACFileIO.cpp:75) fs block size = 1024, macBytes = 8, randBytes = 0 13:19:32 (FileNode.cpp:127) calling setIV on (null) 13:19:32 (RawFileIO.cpp:191) getAttr error on /home/sri/Copy/OfficeData/o94olxB3orqarqyFviHKZ,ZF: No such file or directory 13:19:32 (CipherFileIO.cpp:105) in setIV, current IV = 0, new IV = 16725694203599486310, fileIV = 0 13:19:32 (DirNode.cpp:770) created FileNode for /home/sri/Copy/OfficeData/o94olxB3orqarqyFviHKZ,ZF 13:19:32 (encfs.cpp:134) getattr /home/sri/Copy/OfficeData/o94olxB3orqarqyFviHKZ,ZF 13:19:32 (RawFileIO.cpp:191) getAttr error on /home/sri/Copy/OfficeData/o94olxB3orqarqyFviHKZ,ZF: No such file or directory 13:19:32 (encfs.cpp:138) getattr error: No such file or directory 13:19:32 (encfs.cpp:213) getdir on /home/sri/Copy/OfficeData/ 13:19:32 (BlockNameIO.cpp:185) padding, _bx, finalSize = 208, 16, -192 13:19:32 (DirNode.cpp:132) error decoding filename: eWJrLh2dRFAY-7Brbsc,mTqf 13:19:32 (DirNode.cpp:132) error decoding filename: .encfs6.xml 13:19:32 (BlockNameIO.cpp:185) padding, _bx, finalSize = 218, 16, -202 13:19:32 (DirNode.cpp:132) error decoding filename: pvph9DkZ0BMPg2vN4UcfwuNU 13:24:10 (openssl.cpp:48) Allocating 41 locks for OpenSSL Please help me Thanks in advance.

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• Optimizing AES modes on Solaris for Intel Westmere

  - by danx

  Optimizing AES modes on Solaris for Intel Westmere Review AES is a strong method of symmetric (secret-key) encryption. It is a U.S. FIPS-approved cryptographic algorithm (FIPS 197) that operates on 16-byte blocks. AES has been available since 2001 and is widely used. However, AES by itself has a weakness. AES encryption isn't usually used by itself because identical blocks of plaintext are always encrypted into identical blocks of ciphertext. This encryption can be easily attacked with "dictionaries" of common blocks of text and allows one to more-easily discern the content of the unknown cryptotext. This mode of encryption is called "Electronic Code Book" (ECB), because one in theory can keep a "code book" of all known cryptotext and plaintext results to cipher and decipher AES. In practice, a complete "code book" is not practical, even in electronic form, but large dictionaries of common plaintext blocks is still possible. Here's a diagram of encrypting input data using AES ECB mode: Block 1 Block 2 PlainTextInput PlainTextInput | | | | \/ \/ AESKey-->(AES Encryption) AESKey-->(AES Encryption) | | | | \/ \/ CipherTextOutput CipherTextOutput Block 1 Block 2 What's the solution to the same cleartext input producing the same ciphertext output? The solution is to further process the encrypted or decrypted text in such a way that the same text produces different output. This usually involves an Initialization Vector (IV) and XORing the decrypted or encrypted text. As an example, I'll illustrate CBC mode encryption: Block 1 Block 2 PlainTextInput PlainTextInput | | | | \/ \/ IV >----->(XOR) +------------->(XOR) +---> . . . . | | | | | | | | \/ | \/ | AESKey-->(AES Encryption) | AESKey-->(AES Encryption) | | | | | | | | | \/ | \/ | CipherTextOutput ------+ CipherTextOutput -------+ Block 1 Block 2 The steps for CBC encryption are: Start with a 16-byte Initialization Vector (IV), choosen randomly. XOR the IV with the first block of input plaintext Encrypt the result with AES using a user-provided key. The result is the first 16-bytes of output cryptotext. Use the cryptotext (instead of the IV) of the previous block to XOR with the next input block of plaintext Another mode besides CBC is Counter Mode (CTR). As with CBC mode, it also starts with a 16-byte IV. However, for subsequent blocks, the IV is just incremented by one. Also, the IV ix XORed with the AES encryption result (not the plain text input). Here's an illustration: Block 1 Block 2 PlainTextInput PlainTextInput | | | | \/ \/ AESKey-->(AES Encryption) AESKey-->(AES Encryption) | | | | \/ \/ IV >----->(XOR) IV + 1 >---->(XOR) IV + 2 ---> . . . . | | | | \/ \/ CipherTextOutput CipherTextOutput Block 1 Block 2 Optimization Which of these modes can be parallelized? ECB encryption/decryption can be parallelized because it does more than plain AES encryption and decryption, as mentioned above. CBC encryption can't be parallelized because it depends on the output of the previous block. However, CBC decryption can be parallelized because all the encrypted blocks are known at the beginning. CTR encryption and decryption can be parallelized because the input to each block is known--it's just the IV incremented by one for each subsequent block. So, in summary, for ECB, CBC, and CTR modes, encryption and decryption can be parallelized with the exception of CBC encryption. How do we parallelize encryption? By interleaving. Usually when reading and writing data there are pipeline "stalls" (idle processor cycles) that result from waiting for memory to be loaded or stored to or from CPU registers. Since the software is written to encrypt/decrypt the next data block where pipeline stalls usually occurs, we can avoid stalls and crypt with fewer cycles. This software processes 4 blocks at a time, which ensures virtually no waiting ("stalling") for reading or writing data in memory. Other Optimizations Besides interleaving, other optimizations performed are Loading the entire key schedule into the 128-bit %xmm registers. This is done once for per 4-block of data (since 4 blocks of data is processed, when present). The following is loaded: the entire "key schedule" (user input key preprocessed for encryption and decryption). This takes 11, 13, or 15 registers, for AES-128, AES-192, and AES-256, respectively The input data is loaded into another %xmm register The same register contains the output result after encrypting/decrypting Using SSSE 4 instructions (AESNI). Besides the aesenc, aesenclast, aesdec, aesdeclast, aeskeygenassist, and aesimc AESNI instructions, Intel has several other instructions that operate on the 128-bit %xmm registers. Some common instructions for encryption are: pxor exclusive or (very useful), movdqu load/store a %xmm register from/to memory, pshufb shuffle bytes for byte swapping, pclmulqdq carry-less multiply for GCM mode Combining AES encryption/decryption with CBC or CTR modes processing. Instead of loading input data twice (once for AES encryption/decryption, and again for modes (CTR or CBC, for example) processing, the input data is loaded once as both AES and modes operations occur at in the same function Performance Everyone likes pretty color charts, so here they are. I ran these on Solaris 11 running on a Piketon Platform system with a 4-core Intel Clarkdale processor @3.20GHz. Clarkdale which is part of the Westmere processor architecture family. The "before" case is Solaris 11, unmodified. Keep in mind that the "before" case already has been optimized with hand-coded Intel AESNI assembly. The "after" case has combined AES-NI and mode instructions, interleaved 4 blocks at-a-time. « For the first table, lower is better (milliseconds). The first table shows the performance improvement using the Solaris encrypt(1) and decrypt(1) CLI commands. I encrypted and decrypted a 1/2 GByte file on /tmp (swap tmpfs). Encryption improved by about 40% and decryption improved by about 80%. AES-128 is slighty faster than AES-256, as expected. The second table shows more detail timings for CBC, CTR, and ECB modes for the 3 AES key sizes and different data lengths. » The results shown are the percentage improvement as shown by an internal PKCS#11 microbenchmark. And keep in mind the previous baseline code already had optimized AESNI assembly! The keysize (AES-128, 192, or 256) makes little difference in relative percentage improvement (although, of course, AES-128 is faster than AES-256). Larger data sizes show better improvement than 128-byte data. Availability This software is in Solaris 11 FCS. It is available in the 64-bit libcrypto library and the "aes" Solaris kernel module. You must be running hardware that supports AESNI (for example, Intel Westmere and Sandy Bridge, microprocessor architectures). The easiest way to determine if AES-NI is available is with the isainfo(1) command. For example, $ isainfo -v 64-bit amd64 applications pclmulqdq aes sse4.2 sse4.1 ssse3 popcnt tscp ahf cx16 sse3 sse2 sse fxsr mmx cmov amd_sysc cx8 tsc fpu 32-bit i386 applications pclmulqdq aes sse4.2 sse4.1 ssse3 popcnt tscp ahf cx16 sse3 sse2 sse fxsr mmx cmov sep cx8 tsc fpu No special configuration or setup is needed to take advantage of this software. Solaris libraries and kernel automatically determine if it's running on AESNI-capable machines and execute the correctly-tuned software for the current microprocessor. Summary Maximum throughput of AES cipher modes can be achieved by combining AES encryption with modes processing, interleaving encryption of 4 blocks at a time, and using Intel's wide 128-bit %xmm registers and instructions. References "Block cipher modes of operation", Wikipedia Good overview of AES modes (ECB, CBC, CTR, etc.) "Advanced Encryption Standard", Wikipedia "Current Modes" describes NIST-approved block cipher modes (ECB,CBC, CFB, OFB, CCM, GCM)

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• Why don't languages include implication as a logical operator?

  - by Maciej Piechotka

  It might be a strange question, but why there is no implication as a logical operator in many languages (Java, C, C++, Python Haskell - although as last one have user defined operators its trivial to add it)? I find logical implication much clearer to write (particularly in asserts or assert-like expressions) then negation with or: encrypt(buf, key, mode, iv = null) { assert (mode != ECB --> iv != null); assert (mode == ECB || iv != null); assert (implies(mode != ECB, iv != null)); // User-defined function }

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• Rijndael managed: plaintext length detction

  - by sheepsimulator

  I am spending some time learning how to use the RijndaelManaged library in .NET, and developed the following function to test encrypting text with slight modifications from the MSDN library: Function encryptBytesToBytes_AES(ByVal plainText As Byte(), ByVal Key() As Byte, ByVal IV() As Byte) As Byte() ' Check arguments. If plainText Is Nothing OrElse plainText.Length <= 0 Then Throw New ArgumentNullException("plainText") End If If Key Is Nothing OrElse Key.Length <= 0 Then Throw New ArgumentNullException("Key") End If If IV Is Nothing OrElse IV.Length <= 0 Then Throw New ArgumentNullException("IV") End If ' Declare the RijndaelManaged object ' used to encrypt the data. Dim aesAlg As RijndaelManaged = Nothing ' Declare the stream used to encrypt to an in memory ' array of bytes. Dim msEncrypt As MemoryStream = Nothing Try ' Create a RijndaelManaged object ' with the specified key and IV. aesAlg = New RijndaelManaged() aesAlg.BlockSize = 128 aesAlg.KeySize = 128 aesAlg.Mode = CipherMode.ECB aesAlg.Padding = PaddingMode.None aesAlg.Key = Key aesAlg.IV = IV ' Create a decrytor to perform the stream transform. Dim encryptor As ICryptoTransform = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV) ' Create the streams used for encryption. msEncrypt = New MemoryStream() Using csEncrypt As New CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write) Using swEncrypt As New StreamWriter(csEncrypt) 'Write all data to the stream. swEncrypt.Write(plainText) End Using End Using Finally ' Clear the RijndaelManaged object. If Not (aesAlg Is Nothing) Then aesAlg.Clear() End If End Try ' Return the encrypted bytes from the memory stream. Return msEncrypt.ToArray() End Function Here's the actual code I am calling encryptBytesToBytes_AES() with: Private Sub btnEncrypt_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnEncrypt.Click Dim bZeroKey As Byte() = {&H0, &H0, &H0, &H0, &H0, &H0, &H0, &H0, &H0, &H0, &H0, &H0, &H0, &H0, &H0, &H0} PrintBytesToRTF(encryptBytesToBytes_AES(bZeroKey, bZeroKey, bZeroKey)) End Sub However, I get an exception thrown on swEncrypt.Write(plainText) stating that the 'Length of the data to encrypt is invalid.' However, I know that the size of my key, iv, and plaintext are 16 bytes == 128 bits == aesAlg.BlockSize. Why is it throwing this exception? Is it because the StreamWriter is trying to make a String (ostensibly with some encoding) and it doesn't like &H0 as a value?

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• Received a RAMPAGE IV FORMULA MOBO. Possible CPU Socket problems

  - by Tantan

  I recently received a Rampage IV Formula MOBO in a trade. From everything I read online this seems like a pretty nice piece of hardware. There's one thing I'm worried about though. It appears as though the socket where the CPU goes might have some bent/missing pins. I'm not exactly a computer expert and I wanted to know if this could be any sort of problem. I would post a picture but I apparently don't have enough rep for that... Also, if I did want to move my current rig onto the new MOBO would it even be worth it? MY CURRENT COMPUTER SPECS i3-3220 CPU 8GB DDR3 RAM GeForce GTX460 GPU With a Biostar MOBO!

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• For AES CBC encryption, whats the importance of the IV?

  - by Spines

  What is the security threat of always using all zeroes for the IV? If it allows the encrypted text to be deciphered, how could an attacker do that?

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• Characteristics of an Initialization Vector

  - by Jamie Chapman

  I'm by no means a cryptography expert, I have been reading a few questions around Stack Overflow and on Wikipedia but nothing is really 'clear cut' in terms of defining an IV and it's usage. Points I have discovered: An IV is pre-pended to a plaintext message in order to strengthen the encryption The IV is truely random Each message has it's own unique IV Timestamps and cryptographic hashes are sometimes used instead of random values, but these are considered to be insecure as timestamps can be predicted One of the weaknesses of WEP (in 802.11) is the fact that the IV will reset after a specific amount of encryptions, thus repeating the IV I'm sure there are many other points to be made, what have I missed? (or misread!)

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• Using the Rijndael Object in VB.NET

  - by broke

  I'm trying out the Rijndael to generate an encrypted license string to use for our new software, so we know that our customers are using the same amount of apps that they paid for. I'm doing two things: Getting the users computer name. Adding a random number between 100 and 1000000000 I then combine the two, and use that as the license number(This probably will change in the final version, but I'm just doing something simple for demonstration purposes). Here is some sample codez: Private Sub Main_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load Dim generator As New Random Dim randomValue As Integer randomValue = generator.Next(100, 1000000000) ' Create a new Rijndael object to generate a key ' and initialization vector (IV). Dim RijndaelAlg As Rijndael = Rijndael.Create ' Create a string to encrypt. Dim sData As String = My.Computer.Name.ToString + randomValue.ToString Dim FileName As String = "C:\key.txt" ' Encrypt text to a file using the file name, key, and IV. EncryptTextToFile(sData, FileName, RijndaelAlg.Key, RijndaelAlg.IV) ' Decrypt the text from a file using the file name, key, and IV. Dim Final As String = DecryptTextFromFile(FileName, RijndaelAlg.Key, RijndaelAlg.IV) txtDecrypted.Text = Final End Sub That's my load event, but here is where the magic happens: Sub EncryptTextToFile(ByVal Data As String, ByVal FileName As String, ByVal Key() As Byte, ByVal IV() As Byte) Dim fStream As FileStream = File.Open(FileName, FileMode.OpenOrCreate) Dim RijndaelAlg As Rijndael = Rijndael.Create Dim cStream As New CryptoStream(fStream, _ RijndaelAlg.CreateEncryptor(Key, IV), _ CryptoStreamMode.Write) Dim sWriter As New StreamWriter(cStream) sWriter.WriteLine(Data) sWriter.Close() cStream.Close() fStream.Close() End Sub There is a couple things I don't understand. What if someone reads the text file and recognizes that it is Rijndael, and writes a VB or C# app that decrypts it? I don't really understand all of this code, so if you guys can help me out I will love you all forever. Thanks in advance

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• UIImageView and UIScrollView load lot of pictures

  - by Allan.Chen

  In my app, i use UIImageView and UIScrollView to show lot of pictures(Every time there are about 20 pictures and every pictures about 600px*500px and size is about 600KB ), i use for this code to do this function. Here is code: //Here is pictures Data; self.klpArry = self.pictureData; CGSize size = self.klpScrollView1.frame.size; for (int i=0; i < [klpArr count]; i++) { UIImageView *iv = [[UIImageView alloc] initWithFrame:CGRectMake((size.width * i)+300, 20, 546, 546)]; NSString *filePath = [[NSBundle mainBundle] pathForResource:[klpArr objectAtIndex:i] ofType:@"jpg"]; UIImage *imageData = [[UIImage alloc]initWithData:[NSData dataWithContentsOfFile:filePath]]; [iv setImage:imageData]; iv.backgroundColor = [UIColor grayColor]; [self.klpScrollView1 addSubview:iv]; imageData = nil; iv = nil; iv.image = nil; filePath = nil; [imageData release]; [filePath release]; [iv release]; } // show the picture in scrollview; [self.klpScrollView1 setContentSize:CGSizeMake(size.width * numImage, size.height)]; self.klpScrollView1.pagingEnabled = YES; self.klpScrollView1.showsHorizontalScrollIndicator = NO; self.klpScrollView1.backgroundColor = [UIColor grayColor]; But everytime i init this function, the memory will increase about 5MB, Actually i release UIImageView, UIimage and UIScrollView (vi.image=nil,[vi release]) but i doesn't work, it can't release the memory. BTW, i use my friend code first vi.image=nil then vi=nil; but the pictures not to show on scrollview. any one can help me ?? Thx ~~

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• PHP: Simple, Validate if string is hex?

  - by oni-kun

  I have no clue how to validate this string. I am simply supplying an IV for an encryption, but can find no "is_hex()" or similar function, I can't wrap my head around it! I read on a comment in the php documentation (user contrib. notes) this: if($iv == dechex(hexdec($iv))) { //True } else { //False } But that doesn't seem to work at all.. It only says false. If it helps my input of my IV would be this: 92bff433cc639a6d

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• is this aes encryption wrapper safe ? - yet another take...

  - by user393087

  After taking into accound answers for my questions here and here I created (well may-be) improved version of my wrapper. The key issue was what if an attacker is knowing what is encoded - he might then find the key and encode another messages. So I added XOR before encryption. I also in this version prepend IV to the data as was suggested. sha256 on key is only for making sure the key is as long as needed for the aes alg, but I know that key should not be plain text but calculated with many iterations to prevent dictionary attack function aes192ctr_en($data,$key) { $iv = mcrypt_create_iv(24,MCRYPT_DEV_URANDOM); $xor = mcrypt_create_iv(24,MCRYPT_DEV_URANDOM); $key = hash_hmac('sha256',$key,$iv,true); $data = $xor.((string)$data ^ (string)str_repeat($xor,(strlen($data)/24)+1)); $data = hash('md5',$data,true).$data; return $iv.mcrypt_encrypt('rijndael-192',$key,$data,'ctr',$iv); } function aes192ctr_de($data,$key) { $iv = substr($data,0,24); $data = substr($data,24); $key = hash_hmac('sha256',$key,$iv,true); $data = mcrypt_decrypt('rijndael-192',$key,$data,'ctr',$iv); $md5 = substr($data,0,16); $data = substr($data,16); if (hash('md5',$data,true)!==$md5) return false; $xor = substr($data,0,24); $data = substr($data,24); $data = ((string)$data ^ (string)str_repeat($xor,(strlen($data)/24)+1)); return $data; } $encrypted = aes192ctr_en('secret text','password'); echo $encrypted; echo aes192ctr_de($encrypted,'password'); another question is if ctr mode is ok in this context, would it be better if I use cbc mode ? Again, by safe I mean if an attacter could guess password if he knows exact text that was encrypted and knows above method. I assume random and long password here. Maybe instead of XOR will be safer to random initial data with another run of aes or other simpler alg like TEA or trivium ?

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• WP: AesManaged encryption vs. mcrypt_encrypt

  - by invalidusername

  I'm trying to synchronize my encryption and decryption methods between C# and PHP but something seems to be going wrong. In the Windows Phone 7 SDK you can use AESManaged to encrypt your data I use the following method: public static string EncryptA(string dataToEncrypt, string password, string salt) { AesManaged aes = null; MemoryStream memoryStream = null; CryptoStream cryptoStream = null; try { //Generate a Key based on a Password, Salt and HMACSHA1 pseudo-random number generator Rfc2898DeriveBytes rfc2898 = new Rfc2898DeriveBytes(password, Encoding.UTF8.GetBytes(salt)); //Create AES algorithm with 256 bit key and 128-bit block size aes = new AesManaged(); aes.Key = rfc2898.GetBytes(aes.KeySize / 8); aes.IV = new byte[] { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; // rfc2898.GetBytes(aes.BlockSize / 8); // to check my results against those of PHP var blaat1 = Convert.ToBase64String(aes.Key); var blaat2 = Convert.ToBase64String(aes.IV); //Create Memory and Crypto Streams memoryStream = new MemoryStream(); cryptoStream = new CryptoStream(memoryStream, aes.CreateEncryptor(), CryptoStreamMode.Write); //Encrypt Data byte[] data = Encoding.Unicode.GetBytes(dataToEncrypt); cryptoStream.Write(data, 0, data.Length); cryptoStream.FlushFinalBlock(); //Return Base 64 String string result = Convert.ToBase64String(memoryStream.ToArray()); return result; } finally { if (cryptoStream != null) cryptoStream.Close(); if (memoryStream != null) memoryStream.Close(); if (aes != null) aes.Clear(); } } I solved the problem of generating the Key. The Key and IV are similar as those on the PHP end. But then the final step in the encryption is going wrong. here is my PHP code <?php function pbkdf2($p, $s, $c, $dk_len, $algo = 'sha1') { // experimentally determine h_len for the algorithm in question static $lengths; if (!isset($lengths[$algo])) { $lengths[$algo] = strlen(hash($algo, null, true)); } $h_len = $lengths[$algo]; if ($dk_len > (pow(2, 32) - 1) * $h_len) { return false; // derived key is too long } else { $l = ceil($dk_len / $h_len); // number of derived key blocks to compute $t = null; for ($i = 1; $i <= $l; $i++) { $f = $u = hash_hmac($algo, $s . pack('N', $i), $p, true); // first iterate for ($j = 1; $j < $c; $j++) { $f ^= ($u = hash_hmac($algo, $u, $p, true)); // xor each iterate } $t .= $f; // concatenate blocks of the derived key } return substr($t, 0, $dk_len); // return the derived key of correct length } } $password = 'test'; $salt = 'saltsalt'; $text = "texttoencrypt"; #$iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC); #echo $iv_size . '<br/>'; #$iv = mcrypt_create_iv($iv_size, MCRYPT_RAND); #print_r (mcrypt_list_algorithms()); $iv = "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"; $key = pbkdf2($password, $salt, 1000, 32); echo 'key: ' . base64_encode($key) . '<br/>'; echo 'iv: ' . base64_encode($iv) . '<br/>'; echo '<br/><br/>'; function addpadding($string, $blocksize = 32){ $len = strlen($string); $pad = $blocksize - ($len % $blocksize); $string .= str_repeat(chr($pad), $pad); return $string; } echo 'text: ' . $text . '<br/>'; echo 'text: ' . addpadding($text) . '<br/>'; // -- works till here $crypttext = mcrypt_encrypt(MCRYPT_RIJNDAEL_256, $key, $text, MCRYPT_MODE_CBC, $iv); echo '1.' . $crypttext . '<br/>'; $crypttext = base64_encode($crypttext); echo '2.' . $crypttext . '<br/>'; $crypttext = mcrypt_encrypt(MCRYPT_RIJNDAEL_256, $key, addpadding($text), MCRYPT_MODE_CBC, $iv); echo '1.' . $crypttext . '<br/>'; $crypttext = base64_encode($crypttext); echo '2.' . $crypttext . '<br/>'; ?> So to point out, the Key and IV look similar on both .NET and PHP, but something seems to be going wrong in the final call when executing mcrypt_encrypt(). The end result, the encrypted string, differs from .NET. Can anybody tell me what i'm doing wrong. As far as i can see everything should be correct. Thank you! EDIT: Additional information on the AESManaged object in .NET Keysize = 256 Mode = CBC Padding = PKCS7

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• mcrypt_decrypt return strange code

  - by Jin Yong

  I tried to encrypt an array then decrypt it back to string by calling a function, it's seem return the correct value if I does all encrypt and decrypt at once time in the function, however, if I return the encrypt value, then call the function again to decrypt it will return me some strange code. Exmaple: public main() { $dataArray = array("one"=>1, "two"=>2, "three"=>3); $a = $this->encryptDecryptInfo(json_encode($dataArray),$this->key); var_dump($a); } public function encryptDecryptInfo($text,$key) { $iv = mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, $text= base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_256, $key, $text, MCRYPT_MODE_CFB, $iv)); return mcrypt_decrypt(MCRYPT_RIJNDAEL_256, $key, base64_decode($text), MCRYPT_MODE_CFB, $iv); } This will return me the correct value which is string(27) "{"one":1,"two":2,"three":3}" Exmaple 2: public main() { $dataArray = array("one"=>1, "two"=>2, "three"=>3); $a = $this->encryptDecryptInfo(json_encode($dataArray),$this->key,"encrypt"); $b = $this->encryptDecryptInfo($a,$this->key,"decrypt"); var_dump($b); } public function encryptDecryptInfo($text,$key,$type) { $iv = mcrypt_create_iv(mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_CFB), MCRYPT_RAND); if($type == "encrypt") return base64_encode(mcrypt_encrypt(MCRYPT_RIJNDAEL_256, $key, $text, MCRYPT_MODE_CFB, $iv)); else return mcrypt_decrypt(MCRYPT_RIJNDAEL_256, $key, base64_decode($text), MCRYPT_MODE_CFB, $iv); } However if I do my code in this way, it will return me strange value which is like this string(27) "?ÔérôŸY éXgíœÈÐN*é౜CµÖ" .Deos anyone know why this is happen?

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• Decryption Key value not match

  - by Jitendra Jadav

  public class TrippleENCRSPDESCSP { public TrippleENCRSPDESCSP() { } public void EncryptIt(string sData,ref byte[] sEncData,ref byte[] Key1,ref byte[] Key2) { try { // Create a new TripleDESCryptoServiceProvider object // to generate a key and initialization vector (IV). TripleDESCryptoServiceProvider tDESalg = new TripleDESCryptoServiceProvider(); // Create a string to encrypt. // Encrypt the string to an in-memory buffer. byte[] Data = EncryptTextToMemory(sData,tDESalg.Key,tDESalg.IV); sEncData = Data; Key1 = tDESalg.Key; Key2 = tDESalg.IV; } catch (Exception) { throw; } } public string DecryptIt(byte[] sEncData) { //byte[] toEncrypt = new ASCIIEncoding().GetBytes(sEncData); //XElement xParser = null; //XmlDocument xDoc = new XmlDocument(); try { //string Final = ""; string sPwd = null; string sKey1 = null; string sKey2 = null; //System.Text.ASCIIEncoding encoding = new System.Text.ASCIIEncoding(); string soutxml = ""; //soutxml = encoding.GetString(sEncData); soutxml = ASCIIEncoding.ASCII.GetString(sEncData); sPwd = soutxml.Substring(18, soutxml.LastIndexOf("</EncPwd>") - 18); sKey1 = soutxml.Substring(18 + sPwd.Length + 15, soutxml.LastIndexOf("</Key1>") - (18 + sPwd.Length + 15)); sKey2 = soutxml.Substring(18 + sPwd.Length + 15 + sKey1.Length + 13, soutxml.LastIndexOf("</Key2>") - (18 + sPwd.Length + 15 + sKey1.Length + 13)); //xDoc.LoadXml(soutxml); //xParser = XElement.Parse(soutxml); //IEnumerable<XElement> elemsValidations = // from el in xParser.Elements("EmailPwd") // select el; #region OldCode //XmlNodeList objXmlNode = xDoc.SelectNodes("EmailPwd"); //foreach (XmlNode xmllist in objXmlNode) //{ // XmlNode xmlsubnode; // xmlsubnode = xmllist.SelectSingleNode("EncPwd"); // xmlsubnode = xmllist.SelectSingleNode("Key1"); // xmlsubnode = xmllist.SelectSingleNode("Key2"); //} #endregion //foreach (XElement elemValidation in elemsValidations) //{ // sPwd = elemValidation.Element("EncPwd").Value; // sKey1 = elemValidation.Element("Key1").Value; // sKey2 = elemValidation.Element("Key2").Value; //} //byte[] Key1 = encoding.GetBytes(sKey1); //byte[] Key2 = encoding.GetBytes(sKey2); //byte[] Data = encoding.GetBytes(sPwd); byte[] Key1 = ASCIIEncoding.ASCII.GetBytes(sKey1); byte[] Key2 = ASCIIEncoding.ASCII.GetBytes(sKey2); byte[] Data = ASCIIEncoding.ASCII.GetBytes(sPwd); // Decrypt the buffer back to a string. string Final = DecryptTextFromMemory(Data, Key1, Key2); return Final; } catch (Exception) { throw; } } public static byte[] EncryptTextToMemory(string Data,byte[] Key,byte[] IV) { try { // Create a MemoryStream. MemoryStream mStream = new MemoryStream(); // Create a CryptoStream using the MemoryStream // and the passed key and initialization vector (IV). CryptoStream cStream = new CryptoStream(mStream, new TripleDESCryptoServiceProvider().CreateEncryptor(Key, IV), CryptoStreamMode.Write); // Convert the passed string to a byte array. //byte[] toEncrypt = new ASCIIEncoding().GetBytes(Data); byte[] toEncrypt = ASCIIEncoding.ASCII.GetBytes(Data); // Write the byte array to the crypto stream and flush it. cStream.Write(toEncrypt, 0, toEncrypt.Length); cStream.FlushFinalBlock(); // Get an array of bytes from the // MemoryStream that holds the // encrypted data. byte[] ret = mStream.ToArray(); // Close the streams. cStream.Close(); mStream.Close(); // Return the encrypted buffer. return ret; } catch (CryptographicException e) { MessageBox.Show("A Cryptographic error occurred: {0}", e.Message); return null; } } public static string DecryptTextFromMemory(byte[] Data, byte[] Key, byte[] IV) { try { // Create a new MemoryStream using the passed // array of encrypted data. MemoryStream msDecrypt = new MemoryStream(Data); // Create a CryptoStream using the MemoryStream // and the passed key and initialization vector (IV). CryptoStream csDecrypt = new CryptoStream(msDecrypt, new TripleDESCryptoServiceProvider().CreateDecryptor(Key, IV), CryptoStreamMode.Write); csDecrypt.Write(Data, 0, Data.Length); //csDecrypt.FlushFinalBlock(); msDecrypt.Position = 0; // Create buffer to hold the decrypted data. byte[] fromEncrypt = new byte[msDecrypt.Length]; // Read the decrypted data out of the crypto stream // and place it into the temporary buffer. msDecrypt.Read(fromEncrypt, 0, msDecrypt.ToArray().Length); //csDecrypt.Close(); MessageBox.Show(ASCIIEncoding.ASCII.GetString(fromEncrypt)); //Convert the buffer into a string and return it. return new ASCIIEncoding().GetString(fromEncrypt); } catch (CryptographicException e) { MessageBox.Show("A Cryptographic error occurred: {0}", e.Message); return null; } } }

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• Camera lookAt target changes when rotating parent node

  - by Michael IV

  have the following issue.I have a camera with lookAt method which works fine.I have a parent node to which I parent the camera.If I rotate the parent node while keeping the camera lookAt the target , the camera lookAt changes too.That is nor what I want to achieve.I need it to work like in Adobe AE when you parent camera to a null object:when null object is rotated the camera starts orbiting around the target while still looking at the target.What I do currently is multiplying parent's model matrix with camera model matrix which is calculated from lookAt() method.I am sure I need to decompose (or recompose ) one of the matrices before multiplying them .Parent model or camera model ? Anyone here can show the right way doing it ? UPDATE: The parent is just a node .The child is the camera.The parented camera in AfterEffects works like this: If you rotate the parent node while camera looks at the target , the camera actually starts orbiting around the target based on the parent rotation.In my case the parent rotation changes also Camera's lookAt direction which IS NOT what I want.Hope now it is clear .

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• Index independent character comparison within text blocks

  - by Michael IV

  I have the following task: developing a program where there is a block of sample text which should be typed by user. Any typos the user does during the test are registered. Basically, I can compare each typed char with the sample char based on caret index position of the input, but there is one significant flaw in such a "naive" approach. If the user typed mistakenly more letters than a whole string has, or inserted more white spaces between the string than should be, then the rest of the comparisons will be wrong because of the index offsets added by the additional wrong insertions. I have thought of designing some kind of parser where each string (or even a char ) is tokenized and the comparisons are made "char-wise" and not "index-wise," but that seems to me like an overkill for such a task. I would like to get a reference to possibly existing algorithms which can be helpful in solving this kind of problem.

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• Quaternion based rotation and pivot position

  - by Michael IV

  I can't figure out how to perform matrix rotation using Quaternion while taking into account pivot position in OpenGL.What I am currently getting is rotation of the object around some point in the space and not a local pivot which is what I want. Here is the code [Using Java] Quaternion rotation method: public void rotateTo3(float xr, float yr, float zr) { _rotation.x = xr; _rotation.y = yr; _rotation.z = zr; Quaternion xrotQ = Glm.angleAxis((xr), Vec3.X_AXIS); Quaternion yrotQ = Glm.angleAxis((yr), Vec3.Y_AXIS); Quaternion zrotQ = Glm.angleAxis((zr), Vec3.Z_AXIS); xrotQ = Glm.normalize(xrotQ); yrotQ = Glm.normalize(yrotQ); zrotQ = Glm.normalize(zrotQ); Quaternion acumQuat; acumQuat = Quaternion.mul(xrotQ, yrotQ); acumQuat = Quaternion.mul(acumQuat, zrotQ); Mat4 rotMat = Glm.matCast(acumQuat); _model = new Mat4(1); scaleTo(_scaleX, _scaleY, _scaleZ); _model = Glm.translate(_model, new Vec3(_pivot.x, _pivot.y, 0)); _model =rotMat.mul(_model);//_model.mul(rotMat); //rotMat.mul(_model); _model = Glm.translate(_model, new Vec3(-_pivot.x, -_pivot.y, 0)); translateTo(_x, _y, _z); notifyTranformChange(); } Model matrix scale method: public void scaleTo(float x, float y, float z) { _model.set(0, x); _model.set(5, y); _model.set(10, z); _scaleX = x; _scaleY = y; _scaleZ = z; notifyTranformChange(); } Translate method: public void translateTo(float x, float y, float z) { _x = x - _pivot.x; _y = y - _pivot.y; _z = z; _position.x = _x; _position.y = _y; _position.z = _z; _model.set(12, _x); _model.set(13, _y); _model.set(14, _z); notifyTranformChange(); } But this method in which I don't use Quaternion works fine: public void rotate(Vec3 axis, float angleDegr) { _rotation.add(axis.scale(angleDegr)); // change to GLM: Mat4 backTr = new Mat4(1.0f); backTr = Glm.translate(backTr, new Vec3(_pivot.x, _pivot.y, 0)); backTr = Glm.rotate(backTr, angleDegr, axis); backTr = Glm.translate(backTr, new Vec3(-_pivot.x, -_pivot.y, 0)); _model =_model.mul(backTr);///backTr.mul(_model); notifyTranformChange(); }

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• Specified key is not a valid size for this algorithm...

  - by phenevo

  Hi, I have with this code: RijndaelManaged rijndaelCipher = new RijndaelManaged(); // Set key and IV rijndaelCipher.Key = Convert.FromBase64String("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz012345678912"); rijndaelCipher.IV = Convert.FromBase64String("1234567890123456789012345678901234567890123456789012345678901234"); I get throws : Specified key is not a valid size for this algorithm. Specified initialization vector (IV) does not match the block size for this algorithm. What's wrong with this strings ? Can I count at some examples strings from You ?

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