cryptography - No padding for AES cipher in Java Card -

in javacard 2.2.2 api, can see symmetric ciphers implemented padding mode, example:

cipher algorithm alg_des_cbc_iso9797_m1 provides cipher using des in cbc mode or triple des in outer cbc mode, , pads input data according iso 9797 method 1 scheme.

but aes cipher, there no padding mode available (alg_aes_block_128_ecb_nopad , alg_aes_block_128_cbc_nopad).

so how explain it's not supported algorithm?

are these padding methods vulnerable known attacks using aes?

if other padding modes available depends on java card api using implementation details specific java card.

later api's have:

• a new getinstance method can used pad_pkcs5;
• additional constants such alg_aes_cbc_pkcs5.

the special getinstance method added because of explosion of modes , padding methods.

older api implementations may indeed not have these methods, please again check availability.

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aes block cipher. different modes such cbc use cipher , padding - cbc_aes_pkcs7padding more logical in sense. block cipher, aes therefore not vulnerable padding oracle attacks.

cbc on other hand is vulnerable against padding oracle - , other plaintext oracle - attacks. should protect iv , ciphertext e.g. aes-cmac authentication tag if need protection against these attacks.

that's not reason why padding modes not included. different padding modes are present now.