The StreetPass local-WLAN CCMP data-encryption key is generated via [[NWM_Services|NWM]] module, the input "passphrase" used here is generated by the StreetPass CECD module using [[PS:EncryptDecryptAes]] with keytype6.
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The StreetPass local-WLAN CCMP data-encryption key is generated by the StreetPass CECD module, where the CCMP key is the 16-byte output from encrypting an all-zero block with AES-CTR via [[PS:EncryptDecryptAes]], with keytype6. The CTR is the first 0x10-bytes from a SHA1-HMAC hash. The SHA1-HMAC key is a 17-byte text string including the NULL-terminator, a seperate HMAC key is used for retail/dev-units, this is determined via [[Configuration_Memory|UNITINFO]] bit0. The data hashed with SHA1-HMAC is a 0x1C-byte buffer.