On 05/27/2014 09:00 AM, Anant Rao wrote: > Hi, > > I have ciphertext encrypted in Java (using BouncyCastle - BC) with > "AES/GCM/NoPadding" cipher. > > When I tried to decrypt it using OpenSSL in a 'c' program, the last call > 'EVP_DecryptFinal_ex' fails. Somehow, ERR_print_errors_fp is not > printing anything either. > > I do have the IV that is used in the Java's encrypt. However, I don't > know where BC stores the tag in the ciphertext. I tried it at the > beginning and the end of the ciphertext, but it didn't help. > > That is, I tried both of the following in the decrypt: > > |IV|TAG|Ciphertext > > |IV|Ciphertext|TAG > Both didn't work. > > I tried both of the following as well with the same failure: > EVP_aes_256_gcm > EVP_aes_128_gcm > > I have run out of ideas what else to try. Any help would be greatly > appreciated. > Thanks in advance! > >
Have a look at https://www.openssl.org/docs/crypto/EVP_EncryptInit.html#GCM_Mode and at the example in 'openssl/demos/evp/aesgcm.c' of the current master branch (git://git.openssl.org/openssl.git). Regards Jens ______________________________________________________________________ OpenSSL Project http://www.openssl.org User Support Mailing List openssl-users@openssl.org Automated List Manager majord...@openssl.org
