Secure updating of telecommunication terminal configuration
A network terminal, e.g., a smartphone, can retrieve, from a datastore, a cryptographically-signed configuration record including a device identifier of the terminal. The terminal can transmit a request message comprising the configuration record and the device identifier. A network device can verify authenticity of the device identifier and a match between the identifier in the record and the identifier in the message. In response to confirmation of the request by a policy engine, the network device can determine a reply message comprising a cryptographically-signed second configuration record that includes a second device identifier. The terminal can verify that the signature is valid and that the second device identifier matches the device identifier. In response, the terminal can modify data in the datastore according to the second configuration record. The configuration record can lock or unlock the terminal, or determine permitted services or network peers.
1. A control unit comprising:
at least one processor;
a network interface;
a non-transitory computer readable media storing instructions which when executed by at least one processor cause the at least one processor to perform operations comprising;
identifying a first device identifier in a cleartext portion of an update-request message and a second device identifier in an encrypted portion of the update-request message;
determining that the first device identifier matches the second device identifier;
sending, to a policy engine, a confirmation request;
receiving, from the policy engine, a confirmation;
determining a reply message comprising the device identifier and a configuration record;
cryptographically hashing at least a portion of the reply message to provide a cryptographic signature, wherein the at least a portion of the reply message comprises the at least one of the first device identifier or the second device identifier; and
transmitting, via the network interface, the reply message in association with the cryptographic signature.
2. The control unit according to claim 1 , the operations further comprise:
determining that the update-request message comprises a temporary-unlock request; and
determining a timestamp criterion indicating a time period during which the an authorization requirement should not be enforced.
3. The control unit according to claim 1 , wherein the second device identifier comprises an International Mobile Equipment Identity.
4. The control unit according to claim 1 , wherein the confirmation request requests a permanent unlock and the confirmation grants a temporary unlock.
5. The control unit according to claim 1 , wherein the operations further comprise verifying authenticity of the second device identifier from the update-request message.
6. The control unit according to claim 1 , wherein the operations further comprise receiving, via a communications interface, an update-request message.
7. The control unit according to claim 1 , wherein the update-request message comprises a prior configuration record and the prior configuration record comprises an authorization requirement.
8. The control unit according to claim 1 , further comprising:
determining that the update-request message comprises an unlock request; and
in response, determining the configuration record excluding the authorization requirement.
9. The control unit according to claim 1 , wherein:
determining that the update-request message comprises a temporary-unlock request; and
in response, determining the configuration record comprising:
an authorization requirement; and
a timestamp criterion indicating a time period during which the authorization requirement should not be enforced.
10. At least one non-transitory computer-readable medium storing instructions which, when executed by at least one processor, cause the at least one processor to perform operations comprising:
extracting a first device identifier in a cleartext portion of an update-request message and a second device identifier in an encrypted portion of the update-request message;
determining that the first device identifier matches the second device identifier;
cryptographically signing at least a portion of a reply message to provide a cryptographic signature, wherein the at least a portion of the reply message comprises the first device identifier; and
transmitting, via a communications interface, the reply message in association with the cryptographic signature.
11. The at least one non-transitory computer-readable medium according to claim 10 , wherein the second device identifier is a keyed-hash message authentication code.
12. The at least one non-transitory computer-readable medium according to claim 10 , storing additional instructions which, when executed by the at least one processor, cause the at least one processor to perform operations comprising:
in response to determining that the first device identifier matches the second device identifier, providing, to a policy engine, a confirmation request;
receiving, from the policy engine, a confirmation; and
in response to the confirmation, generating the reply message comprising the device identifier and a configuration record.
13. The at least one non-transitory computer-readable medium according to claim 12 , wherein the confirmation request requests a permanent unlock and the confirmation grants a temporary unlock.
14. The at least one non-transitory computer-readable medium according to claim 13 , wherein the confirmation indicates a status of the temporary unlock and period of time at which the temporary unlock expires.
15. The at least one non-transitory computer-readable medium according to claim 10 , storing additional instructions which, when executed by the at least one processor, cause the at least one processor to perform operations comprising:
verifying authenticity of the second device identifier based at least in part on contents of the update-request message.
16. The at least one non-transitory computer-readable medium according to claim 10 , wherein the cryptographic signature is a public-key signature that has been cryptographically hashed using at least one of a Rivest-Shamir-Adleman Signature Scheme with Appendix—Probabilistic Signature Scheme (RSA-SSA-PSS) or Public Key Cryptography Standard (PKCS) signature techniques.
17. A method comprising, by a control unit of a network device:
receiving, via a communications interface, an update-request message;
extracting a first device identifier in a cleartext portion of the update-request message and a second device identifier in an encrypted portion of from the update-request message;
verifying authenticity of the second device identifier from the update-request message;
determining that the first device identifier matches the second device identifier;
in response to determining that the first device identifier matches the second device identifier, providing, to a policy engine, a confirmation request;
receiving, from the policy engine, a confirmation;
in response to the confirmation, determining a reply message comprising the device identifier and a configuration record;
cryptographically signing at least a portion of the reply message to provide a cryptographic signature, wherein the at least a portion of the reply message comprises the first device identifier; and
transmitting, via the communications interface, the reply message in association with the cryptographic signature.
18. The method according to claim 17 , wherein:
the update-request message comprises a prior configuration record;
the prior configuration record comprises an authorization requirement; and
the method further comprises, by the control unit of the network device:
determining that the update-request message comprises an unlock request; and
in response, determining the configuration record excluding the authorization requirement.
19. The method according to claim 17 , wherein:
the update-request message comprises a prior configuration record;
the prior configuration record comprises an authorization requirement; and
the method further comprises, by the control unit of the network device:
determining that the update-request message comprises a temporary-unlock request; and
in response, determining the configuration record comprising:
the authorization requirement; and
a timestamp criterion indicating a time period during which the authorization requirement should not be enforced.
20. The method according to claim 17 , wherein the second device identifier comprises an International Mobile Equipment Identity.