APT:Wrap

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Request

Index Word Description
0 Header code [0x00460104]
1 Output buffer size
2 Input buffer size
3 Block size
4 Nonce size, size 12 is used if this is >12.
5 (inputbufsize<<4) | 10
6 Input cleartext data buffer ptr
7 (outputbufsize<<4) | 12
8 Output encrypted data buffer ptr

Response

Index Word Description
0 Header code
1 Result code

Description

This encrypts the input data with AES-CCM using keytype2, when the input noncesize is <12 the low 2-bits are cleared in the noncesize. The 12-byte nonce buffer used by NS is cleared to all-zero, then the nonce from inputbuf+blocksize with the noncesize is copied to this nonce buffer. NS then copies the data at inputbuf+0 to outbuf+noncesize, with the blocksize.

NS then copies the data at inbuf+blocksize+noncesize to outbuf+blocksize, with size inputbuffersize-blocksize-noncesize. NS then uses PS:EncryptSignDecryptVerifyAesCcm with keytype2 and with the above nonce buffer, where the input/output buffer ptrs are outbuf+noncesize, with size blocksize+(inputbuffersize-blocksize-noncesize). NS then copies the the nonce from the nonce-buffer with the noncesize, to outbuf+0.