Identity based signature in system information protection
A network entity may provision a UE and a base station with parameters for securing network communications. The network entity may send a system parameter to a UE and a private security key to a base station. Additionally, the UE and the base station may each receive synchronization information from the network which may be used to create a randomness parameter. The base station may create a signature based on the private security key, a cell identifier, and the randomness parameter and include the signature in a system information message that is to be broadcasted to one or more UEs. A UE connecting to the base station may receive the system information message from the base station, determine the cell identifier, and verify the system information message based on one or more of the cell identifier, the system parameter, or the randomness parameter.
1. A method for wireless communication at a user equipment (UE), comprising:
receiving a system parameter identified by a network entity;
determining synchronization information based at least in part on a synchronization signal, the synchronization information being indicative of, at least in part, a system frame number, a hyper system frame number, or both;
determining a randomness parameter based at least in part on the system frame number, the hyper system frame number, or a combination thereof;
verifying that the randomness parameter is different than a randomness parameter used in a previous session or that the randomness parameter is within an error range based at least in part on an estimated value derived from the system frame number and the hyper system frame number;
receiving a system information message, the system information message comprising a signature that indicates that the system information message is associated with a cell identifier associated with a base station, wherein the signature is based at least in part on the system parameter and the randomness parameter;
determining the cell identifier from the system information message;
verifying the signature based at least in part on one or more of the cell identifier, the system parameter, or the randomness parameter.
2. The method of claim 1 , further comprising:
verifying that the randomness parameter is greater than the randomness parameter used in the previous session.
3. The method of claim 1 , further comprising applying system information from the system information message based at least in part on verifying the signature.
4. The method of claim 1 , wherein verifying the signature comprises:
determining that the randomness parameter has not been replayed from a previous session.
5. The method of claim 1 , wherein verifying the signature comprises:
determining that the randomness parameter has been replayed from a previous session; and
performing a cell reselection procedure based at least in part on determining that the randomness parameter has been replayed.
6. The method of claim 1 , wherein receiving the system parameter further comprises:
receiving the system parameter via an access and mobility management function during a registration procedure.
7. The method of claim 1 , wherein receiving the system parameter further comprises:
receiving one or more system parameters, wherein the one or more system parameters are indexed.
8. The method of claim 1 , wherein the cell identifier is further associated with a public land mobile network identifier.
9. The method of claim 1 , wherein the network entity is a security anchor function, a public key generator, or a combination thereof.
10. A method for wireless communication at a base station, comprising:
receiving a private security key generated at a network entity;
determining synchronization information based at least in part on a synchronization signal, the synchronization information being indicative of, at least in part, a system frame number, a hyper system frame number, or both;
determining a randomness parameter based at least in part on the system frame number, the hyper system frame number, or a combination thereof;
verifying that the randomness parameter is different than a randomness parameter used in a previous session or that the randomness parameter is within an error range based at least in part on an estimated value derived from the system frame number and the hyper system frame number;
determining a signature that indicates that a system information message is associated with a cell identifier associated with the base station, wherein the signature is based at least in part on the private security key and the randomness parameter;
including the signature with the system information message; and
transmitting the system information message to one or more user equipments (UEs).
11. The method of claim 10 , further comprising:
verifying that the randomness parameter is greater than the randomness parameter used in a previous session.
12. The method of claim 10 , wherein determining the randomness parameter comprises:
determining that the randomness parameter has not been replayed from a previous session.
13. The method of claim 10 , wherein transmitting the system information message comprises:
including the cell identifier in the system information message.
14. The method of claim 13 , wherein the cell identifier is associated with the base station, a public land mobile network identifier, or a combination thereof.
15. The method of claim 10 , wherein the private security key is based at least in part on a cell identifier of a cell associated with the base station.
16. The method of claim 10 , wherein the network entity is a security anchor function, a public key generator, or a combination thereof.
17. An apparatus for wireless communication at a user equipment (UE), comprising:
a processor,
memory in electronic communication with the processor; and
wherein the processor and the memory are configured to:
receive a system parameter identified by a network entity;
determine synchronization information based at least in part on a synchronization signal, the synchronization information being indicative of, at least in part, a system frame number, a hyper system frame number, or both;
determine a randomness parameter based at least in part on the system frame number, the hyper system frame number, or a combination thereof;
verify that the randomness parameter is different than a randomness parameter used in a previous session or that the randomness parameter is within an error range based at least in part on an estimated value derived from the system frame number and the hyper system frame number;
receive a system information message, the system information message comprising a signature that indicates that the system information message is associated with a cell identifier associated with a base station, wherein the signature is based at least in part on the system parameter and the randomness parameter;
determine the cell identifier from the system information message;
verify the signature based at least in part on one or more of the cell identifier, the system parameter, or the randomness parameter.
18. The apparatus of claim 17 , wherein the processor and the memory are further configured to:
verify that the randomness parameter is greater than a randomness parameter used in a previous session.
19. The apparatus of claim 17 , wherein the processor and the memory are further configured to apply system information from the system information message based at least in part on verifying the signature.
20. An apparatus for wireless communication at a base station, comprising:
a processor,
memory in electronic communication with the processor; and
wherein the processor and the memory are configured to:
receive a private security key generated at a network entity;
determine synchronization information based at least in part on a synchronization signal, the synchronization information being indicative of, at least in part, a system frame number, a hyper system frame number, or both;
determine a randomness parameter based at least in part on the system frame number, the hyper system frame number, or a combination thereof;
verify that the randomness parameter is different than a randomness parameter used in a previous session or that the randomness parameter is within an error range based at least in part on an estimated value derived from the system frame number and the hyper system frame number;
determine a signature that indicates that a system information message is associated with a cell identifier associated with the base station, wherein the signature is based at least in part on the private security key and the randomness parameter;
include the signature with the system information message; and
initiate transmission of the system information message to one or more user equipments (UEs).
21. The apparatus of claim 20 , wherein the processor and the memory are further configured to:
verify that the randomness parameter is greater than a randomness parameter used in a previous session.