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Revision as of 05:28, 22 November 2015 by Steveice10 (talk | contribs)
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Index Word Description
0 Header code [0x00470104]
1 Output Size
2 Input Size
3 Block Size
4 Nonce Size (capped to 12)
5 (Input Size << 4) | 0xA
6 void*, Input
7 (Output Size << 4) | 0xC
8 void*, Output


Index Word Description
0 Header code
1 Result code


This decrypts 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+0 with the noncesize is copied to this nonce buffer. NS then uses PS:EncryptSignDecryptVerifyAesCcm with keytype2 and with the above nonce buffer, where the inputptr is inputbuf+noncesize, outputptr is outputbuf+0, and size is inputbuffersize - noncesize - 16.

After decryption, NS copies the data at outbuf+blocksize to outbuf+blocksize+noncesize, with size inputbuffersize-blocksize-16. NS then copies the nonce from inputbuf+0 with the noncesize, to outbuf+blocksize.