decrypting aes-gcm encrypted with java using openssl
I copied the Base64 output into a file (test-in), and tried decrypting it using the following command ... Authenticated encryption modes do not work from the command line tools. From the openssl enc man page: The enc program does not support authenticated encryption modes like CCM and GCM. The...
AES/GCM with GunZip, cannot decompress correctly
c++,qt,encryption,crypto++,aes-gcm
This was trivial in the end. ALWAYS MAKE SURE YOU PASS ivSize into GCM< AES >::Decryption d; d.SetKeyWithIV(key, keyLength, iv, blockSize); and GCM< AES >::Encryption e; e.SetKeyWithIV(key, keyLength, iv, blockSize); even though they are optional. Failure to do so will result in incorrect decryption...
AES, 128 and 256 Invalid Key Length
c++,encryption,aes,crypto++,aes-gcm
Bytes are usually octets (8 bits). AES is specified for 128-bit block size or 16 bytes which is also the size of the IV. AES key sizes may be 128-bit, 192-bit or 256-bit or 16 byte, 24 byte or 32 byte respectively. They can't be different from those. So use...
decrypt TLS 1.2 AES-GCM packet
java,ssl,encryption,bouncycastle,aes-gcm
GCM mode computes MAC from message, associated data and public nonce, you covered it very well. I think you are using wrong length, it should be plaintext length before encrypting and appending MAC. Try 45 - 8 (explicit nonce) - 16 (MAC) = 21....
AES-256-GCM mode decryption fails in php
php,encryption,openssl,aes,aes-gcm
Testing his out on my system (PHP 5.3.10 using return OpenSSL 1.0.1 internally) returns a ciphertext that has the same length as the plaintext (message). This means that GCM encryption does not return the authentication tag, just the internal CTR mode encryption. This is likely because the PHP wrapper simply...
GCM authenticated encryption function for PHP
php,encryption,encryption-symmetric,aes-gcm
If OpenSSL is not installed then, there is no other method besides looking for a plain PHP implementation on the web. If it is installed, you can check with openssl_get_cipher_methods() whether the installed version supports GCM. Use it like this: $iv = openssl_random_pseudo_bytes(16, true); $key = openssl_random_pseudo_bytes(16, true); $data =...
Unable to get correct output from AES-128-GCM
c++,encryption,cryptography,aes-gcm,polarssl
I can see two immediate mistakes: the plain text size is set to 10 bytes instead of no bytes at all - this makes the ciphertext too large and the authentication tag incorrect; the IV is 12 bytes set to 0 instead of 16 bytes set to 0 - 12...
Reading AES/GCM encoded data in chunks with BouncyCastle in Java
java,encryption,bouncycastle,aes-gcm
Block ciphers [ed: in Bouncy Castle] have an internal buffer that they keep updating, and only when they have enough data for a full block, will the decrypt occur, and a chunk of the decrypted data be returned. You can see this if you try and decrypt it 1 byte...