Fuse based replay protection with dynamic fuse usage and countermeasures for fuse voltage cut attacks

A method implemented in a system on a chip (SOC), the method comprising:

• initializing a trusted platform module (TPM) implemented in the SOC, the TPM comprising an on-die random access memory (RAM) storing:
• a blown-fuse count comprising a count of blown fuses;
• and
• a TPM state comprising a TPM state fuse count and a TPM state personal identification number (PIN)-attempt-failure count;
• in response to the blown-fuse count being greater than the TPM state fuse count, incrementing the TPM state PIN-attempt-failure count;
• receiving a PIN in an attempt to access a system protected by the TPM;
• determining the TPM state PIN-attempt-failure count for the PIN satisfies a PIN-attempt-failure count policy;
• determining a previously-passed-PIN value for the PIN indicates that the PIN was not previously verified to be correct;
• blowing a fuse;
• incrementing the blown-fuse count;
• and
• setting the TPM state fuse count based on the blown-fuse count.

A device comprising:

• a system on a chip (SOC) comprising:
• a plurality of programmable fuses;
• a processor;
• a memory device comprising an on-die random access memory (RAM) storing:
• a blown-fuse count comprising a count of currently blown fuses of the plurality of programmable fuses;
• a trusted platform module (TPM) state for a TPM, wherein the TPM state comprises:
• a TPM state fuse count;
• and
• a TPM state personal identification number (PIN)-attempt-failure count;
• and
• computer executable instructions that, when executed by the processor, perform operations comprising:
• in response to the blown-fuse count being greater than the TPM state fuse count, incrementing the TPM state PIN-attempt-failure count;
• receiving a PIN in an attempt to access a system protected by the TPM;
• determining the TPM state PIN-attempt-failure count for the PIN satisfies a PIN-attempt-failure count policy;
• determining a previously-passed-PIN value for the PIN indicates that the PIN was previously verified to be correct;
• determining the PIN is incorrect;
• blowing a fuse;
• incrementing the blown-fuse count;
• and
• setting the TPM state fuse count based on the blown-fuse count.