Integrity protection of uplink data

1. A method for uplink data integrity protection verification, the method comprising:

receiving, by a target node and from a user equipment (UE), a radio resource control (RRC) message comprising a message authentication code-integrity (MAC-I);

receiving, by the target node and from a source node of a radio access network (RAN), an original KeNB;

deriving, by the target node, a new key KeNB* based on the original KeNB;

calculating, by the target node, a hash code based on the RRC message and the new key KeNB*; and

verifying, by the target node, integrity protection of the RRC message based on the hash code and the received MAC-I.

2. The method of claim 1 , the method further comprising:

receiving, by the target node and from the source node, handover data for a prior communication session between the UE and the source node; and

requesting and receiving from the source node a UE context.

3. The method of claim 2 , the method further comprising:

determining, based on the UE context, that the UE supports integrity protection of uplink data.

4. The method of claim 2 , wherein requesting and receiving from the source node the UE context comprises:

sending a modified X2 application protocol layer (X2AP) retrieve UE context request message to the source node; and

receiving, from the source node, a modified X2AP retrieve UE context response message.

5. The method of claim 1 , wherein verifying integrity protection of the RRC message based on the hash code and the received MAC-I comprises:

calculating a comparison MAC-I based on the hash code and using an integrity protection and ciphering algorithm;

comparing the comparison MAC-I to the received MAC-I; and

determining, based on the comparison, that the integrity protection verification is successful.

6. The method of claim 5 , wherein calculating the comparison MAC-I is further based on an access stratum (AS) key.

7. The method of claim 6 , wherein the AS key is received from a second node of the RAN.

8. The method of claim 1 , wherein deriving the new key KeNB* based on the original KeNB comprises deriving a new nodeB key based on an original nodeB key.

9. An apparatus that includes one or more processors configured to perform operations comprising:

receiving, by a target node and from a user equipment (UE), a radio resource control (RRC) message comprising a message authentication code-integrity (MAC-I);

receiving, by the target node and from a source node of a radio access network (RAN), an original KeNB;

deriving, by the target node, a new key KeNB* based on the original KeNB;

calculating, by the target node, a hash code based on the RRC message and the new key KeNB*; and

verifying, by the target node, integrity protection of the RRC message based on the hash code and the received MAC-I.

10. The apparatus of claim 9 , the operations further comprising:

receiving, by the target node and from the source node, handover data for a prior communication session between the UE and the source node; and

requesting and receiving from the source node a UE context.

11. The apparatus of claim 10 , the operations further comprising:

determining, based on the UE context, that the UE supports integrity protection of uplink data.

12. The apparatus of claim 10 , wherein requesting and receiving from the source node the UE context comprises:

sending a modified X2 application protocol layer (X2AP) retrieve UE context request message to the source node; and

receiving, from the source node, a modified X2AP retrieve UE context response message.

13. The apparatus of claim 9 , wherein verifying integrity protection of the RRC message based on the hash code and the received MAC-I comprises:

calculating a comparison MAC-I based on the hash code and using an integrity protection and ciphering algorithm;

comparing the comparison MAC-I to the received MAC-I; and

determining, based on the comparison, that the integrity protection verification is successful.

14. The apparatus of claim 13 , wherein calculating the comparison MAC-I is further based on an access stratum (AS) key.

15. The apparatus of claim 14 , wherein the AS key is received from a second node of the RAN.

16. A base station comprising one or more processors configured to perform operations comprising:

receiving, from a user equipment (UE), a radio resource control (RRC) message comprising a message authentication code-integrity (MAC-I);

receiving from a second node of a radio access network (RAN) an original KeNB;

deriving a new key KeNB* based on the original KeNB;

calculating a hash code based on the RRC message and the new key KeNB*; and

verifying integrity protection of the RRC message based on the hash code and the received MAC-I.

17. The base station of claim 16 , wherein the UE has undergone handover from the second node of the RAN to the base station, and the operations further comprising:

requesting and receiving from the second node a UE context.

18. The base station of claim 17 , the operations further comprising:

determining, based on the UE context, that the UE supports integrity protection of uplink data.

19. The base station of claim 17 , wherein requesting and receiving from the second node the UE context comprises:

sending a modified X2 application protocol layer (X2AP) retrieve UE context request message to the second node; and

receiving, from the second node, a modified X2AP retrieve UE context response message.

20. The base station of claim 16 , wherein verifying integrity protection of the RRC message based on the hash code and the received MAC-I comprises:

calculating a comparison MAC-I based on the hash code and using an integrity protection and ciphering algorithm;

comparing the comparison MAC-I to the received MAC-I; and

determining, based on the comparison, that the integrity protection verification is successful.