Countermeasure for power injection security attack
A system and method for determining whether a cryptographic system is being observed for power consumption analysis in an attempt to decipher secret keys. The system comprises a first external connection to receive an input voltage, an internal voltage regulator with an external capacitor to produce the desired voltage for the cryptographic system. The internal voltage regulator typically includes a switch that passes current from the first external connection to the external capacitor. By monitoring the frequency at which the switch is activated, it is possible to detect that an external voltage is being applied to the external capacitor. This external voltage is typically used to perform SPA or DPA operations. Thus, the cryptographic system may cease performing any encryption or decryption operations if an external voltage is detected.
1. An electronic component, comprising:
a first external connection to receive an input voltage;
a second external connection, maintained at an operating voltage;
an internal voltage regulator, in communication with the first external connection and the second external connection, comprising an internal switching component in communication with the first external connection and the second external connection to supply current from the input voltage to the second external connection to maintain the second external connection at the operating voltage, wherein the internal switching component is controlled by a signal from the internal voltage regulator, wherein the signal has an asserted state wherein a current flows from the first external connection to the second external connection and a deasserted state where the current does not flow;
a monitoring circuit in communication with the signal; and
a cryptographic system;
wherein the monitoring circuit determines whether power consumption analysis is being performed at the second external connection by monitoring at least one of:
a number of positive transitions of the signal;
a number of negative transitions of the signal;
a number of negative and positive transitions of the signal;
an amount of time that the signal is asserted; or
a duration of time that the signal is deasserted;
and wherein behavior of the cryptographic system is modified if power consumption analysis is being performed.
2. The electronic component of claim 1 , wherein the cryptographic system is disabled if power consumption analysis is being performed.
3. An electronic component, comprising:
a first external connection to receive an input voltage;
a second external connection, maintained at an operating voltage;
an internal voltage regulator, in communication with the first external connection and the second external connection, comprising an internal switching component in communication with the first external connection and the second external connection to supply current from the input voltage to the second external connection to maintain the second external connection at the operating voltage, wherein the internal switching component is controlled by a signal from the internal voltage regulator, wherein the signal comprises an asserted state wherein a current flows from the first external connection to the second external connection and a deasserted state where the current does not flow;
a monitoring circuit in communication with the signal to determine whether power consumption analysis is being performed at the second external connection by monitoring at least one of:
a number of positive transitions of the signal;
a number of negative transitions of the signal;
a number of negative and positive transitions of the signal;
an amount of time that the signal is asserted; or
a duration of time that the signal is deasserted;
a cryptographic system; and
a processing unit, wherein the monitoring circuit alerts the processing unit if power consumption analysis is being performed.
4. The electronic circuit of claim 3 , wherein the monitoring circuit causes an interrupt to the processing unit.
5. The electronic circuit of claim 3 , wherein the monitoring circuit causes a bit in a register, readable by the processing unit, to be modified.
6. The electronic component of claim 3 , wherein the processing unit modifies an operation of the cryptographic system if power consumption analysis is being performed.
7. The electronic component of claim 6 , wherein the processing unit disables operation of the cryptographic system if power consumption analysis is being performed.
8. An electronic component, comprising:
a first external connection to receive an input voltage;
a second external connection, maintained at an operating voltage;
an internal voltage regulator, in communication with the first external connection and the second external connection, comprising an internal switching component in communication with the first external connection and the second external connection to supply current from the input voltage to the second external connection to maintain the second external connection at the operating voltage, wherein the internal switching component is controlled by a signal from the internal voltage regulator;
a monitoring circuit in communication with the signal, wherein the monitoring circuit determines whether power consumption analysis is being performed at the second external connection by monitoring at least one of:
a number of positive transitions of the signal;
a number of negative transitions of the signal;
a number of negative and positive transitions of the signal;
an amount of time that the signal is asserted; or
a duration of time that the signal is deasserted;
a cryptographic system; and
a Secure Element in communication with the monitoring circuit; wherein a Secure Element is defined as a tamper-resistant platform capable of securely hosting applications and their confidential and cryptographic data in accordance with rules and security requirements set forth by a set of well-identified trusted authorities.
9. The electronic component of claim 8 , wherein the Secure Element undertakes countermeasures if power consumption analysis is being performed.
10. The electronic component of claim 9 , wherein the Secure Element disables the cryptographic system if power consumption analysis is being performed.
11. The electronic component of claim 9 , wherein the Secure Element deletes all encryption keys stored in the electronic component if power consumption analysis is being performed.
12. The electronic component of claim 9 , wherein the Secure Element replaces all encryption keys stored in the electronic component with random values if power consumption analysis is being performed.
13. The electronic component of claim 9 , wherein the Secure Element resets the electronic component if power consumption analysis is being performed.