This class can be used decrypt data created with LockBox3 and encrypt data that will be properly handled by LockBox3. LockBox3 is an encryption/decryption library for Delphi.
There are actually three classes, LB3AES, LB3AESECB and LB3AESCBC. The only class that is used to instantiate an object is LB3AES. There are only 3 methods:
1) Initialize(keySize As Int, password As String, mode As String)
keySize is one of 128, 192, or 256.
password is the password to be used for encrypting/decrypting.
mode is the block chain mode used. Currently supports "ECB" and "CBC"
2) DecryptString(cipherText As String) As String
This method will decrypt a given cipher text produced by ToolBox3
3) EncryptString(plainText As String) As String
This method will encrypt a given plain text that will be understood by ToolBox3
Please note: Both ToolBox3 and this class will have to use the same keySize, password, and mode for a given ciphertext/plaintext to be properly handled. Delphi must use UTF8 for all encodings (password and text to be encrypted/decrypted).
For a write up on how I derived at this implementation, see https://www.b4x.com/android/forum/t...i-aes-encryption-exchange-with-b4a-b4j.97959/.
2019/08/26: CBC Mode update:
2018/10/25: B4J Specific update:
There are actually three classes, LB3AES, LB3AESECB and LB3AESCBC. The only class that is used to instantiate an object is LB3AES. There are only 3 methods:
1) Initialize(keySize As Int, password As String, mode As String)
keySize is one of 128, 192, or 256.
password is the password to be used for encrypting/decrypting.
mode is the block chain mode used. Currently supports "ECB" and "CBC"
2) DecryptString(cipherText As String) As String
This method will decrypt a given cipher text produced by ToolBox3
3) EncryptString(plainText As String) As String
This method will encrypt a given plain text that will be understood by ToolBox3
Please note: Both ToolBox3 and this class will have to use the same keySize, password, and mode for a given ciphertext/plaintext to be properly handled. Delphi must use UTF8 for all encodings (password and text to be encrypted/decrypted).
For a write up on how I derived at this implementation, see https://www.b4x.com/android/forum/t...i-aes-encryption-exchange-with-b4a-b4j.97959/.
2019/08/26: CBC Mode update:
The CBC mode encryption/decryption did not work properly for plaintext/ciphertext messages that were longer than 16 bytes and whose length were not evenly divisible by 16. I'll update my write up for the solution to this issue.
As to the #MergedLibraries option, it looks like any JDK's based on OpenJDK (be it version 8 or 11) do not seem to have an issue with this option being set to True. The only JDK that seems to have issues with this is Oracle's implementation. See https://www.b4x.com/android/forum/threads/cannot-merge-external-library.109003
2018/10/25: B4J Specific update:
If you want greater than 128bit encryption:
The Bouncy Castle .jar file that is required (as of this writing bcprov-jdk15on-160.jar, located here https://www.bouncycastle.org/latest_releases.html) is signed. In order for this library to work in Release mode (as it pertains to using these classes), the #MergeLibraries option must be set to False (see https://www.b4x.com/android/forum/threads/sshj-ssh-scp-sftp-for-java.88615/page-3#post-589290). This will have an implication on your application for distribution, since one needs to now include any library .jar files with the application. OpenJDK (at least version 11.0.1) does not seem to care how that option is set.
The only change done to the previous upload is to set #MergeLibraries to False in the B4J project
Thanks to @Diceman for bringing these issues to light.
For JRE/JDK before 1.8.0_151, see https://stackoverflow.com/a/6481658
For JRE/JDK starting with 1.8.0_151 and 9, see https://www.petefreitag.com/item/844.cfm
For JRE/JDK after 9, you should be good to go.
Please note that this does depend on your region not being restricted from using strong cryptography.For JRE/JDK starting with 1.8.0_151 and 9, see https://www.petefreitag.com/item/844.cfm
For JRE/JDK after 9, you should be good to go.
The Bouncy Castle .jar file that is required (as of this writing bcprov-jdk15on-160.jar, located here https://www.bouncycastle.org/latest_releases.html) is signed. In order for this library to work in Release mode (as it pertains to using these classes), the #MergeLibraries option must be set to False (see https://www.b4x.com/android/forum/threads/sshj-ssh-scp-sftp-for-java.88615/page-3#post-589290). This will have an implication on your application for distribution, since one needs to now include any library .jar files with the application. OpenJDK (at least version 11.0.1) does not seem to care how that option is set.
The only change done to the previous upload is to set #MergeLibraries to False in the B4J project
Thanks to @Diceman for bringing these issues to light.
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