ID TECH SecureHead SPI with TMIV User Manual
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1.
First, the host would get a data block which is generated by encrypting a random 8-byte data
using TDES algorithm.
2.
The host then decrypts the data block using TDES algorithm using the current device key.
3.
The host initiates an External Authenticate Command to verify the decrypted 8 bytes of
random data
4.
The device checks to see if the data matches the random data generated. If the data are the
same, authentication process is successful. If it fails, the host must start the authentication
process again until it succeeds before any security related featured can be changed.
4.13.3.
Retrieve Encrypted Challenge Command
Host -> Device:
Command:
<STX><R><74h><ETX><CheckSum>
Device -> Host:
Command:
<ACK><STX><8 bytes of TDES-encrypted random data><ETX><CheckSum> (success)
<NAK> (fail)
4.13.4.
Send External Authenticate Command Host -> Device:
Command:
<STX><S><74h><08h><8 bytes of original random data><ETX><CheckSum>
Device -> Host:
<ACK> (success)
<NAK> (fail)
4.14.
Encryption Settings
Enable or disable the SecureHead Encryption output in ID TECH protocol. If encryption is disabled,
original data will be sent out to the host. If it enabled, encrypted data will be sent out to the host.
Command:
<STX><S><4Ch><01h><Encryption Settings><ETX><CheckSum>
Encryption Settings:
•
“0” Encryption Disabled
•
“1” Enable TDES Encryption
•
“2” Enable AES Encryption