Let me guess. Not flushing/closing the stream? On Oct 3, 2019, at 8:41 PM, Benoit Laforest <benoit.lafor...@ubisoft.com> wrote:
Hi, Ok, I found my problem, it was a dumb-and-very-hard-to-see error on my side… Every thing works now. 😊 Yay. Benoit De : Benoit Laforest <benoit.lafor...@ubisoft.com> Envoyé : 3 octobre 2019 17:25 À : dev-crypto-csharp@bouncycastle.org Objet : [dev-crypto-csharp] HELP: stuck with the exception "mac check in GCM failed" during decryption Hi, I am testing the decryption with the GcmCypherBlock and I am totally stuck with the exception “mac check in GCM failed” when I call DoFinal(). * The encryption does not generate any problem, and I use the same secret symmetric key, public IV and additional text in the Aead param for both encryption and decryption. I also performed the DH exchange correctly wih the X25519 agreement to compute my symmetric key. * I use a 128 bit IV and mac and a 256 bits key size * I also tried this code sample from this web site to compare and it worked fine: https://codereview.stackexchange.com/questions/110952/bouncycastle-diffie-hellman * I event tried this code sample with the X25519 and using the same “secret message” and it still worked… So now I am a bit clueless as to what can go wrong. Thanks, Benoit
