TEEP M. Pei Internet-Draft Symantec Intended status: Informational A. Atyeo Expires: April 26, 2019 Intercede N. Cook ARM Ltd. M. Yoo IoTrust H. Tschofenig ARM Ltd. October 23, 2018 The Open Trust Protocol (OTrP) draft-ietf-teep-opentrustprotocol-02.txt Abstract This document specifies the Open Trust Protocol (OTrP), a protocol that follows the Trust Execution Environment Provisioning (TEEP) architecture and provides a message protocol that provisions and manages Trusted Applications into a device with a Trusted Execution Environment (TEE). Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on April 26, 2019. Copyright Notice Copyright (c) 2018 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents Pei, et al. Expires April 26, 2019 [Page 1] Internet-Draft OTrP October 2018 (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 5 2. Requirements Language . . . . . . . . . . . . . . . . . . . . 6 3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 6 3.1. Definitions . . . . . . . . . . . . . . . . . . . . . . . 6 3.2. Abbreviations . . . . . . . . . . . . . . . . . . . . . . 6 4. OTrP Entities and Trust Model . . . . . . . . . . . . . . . . 6 4.1. System Components . . . . . . . . . . . . . . . . . . . . 7 4.2. Trust Anchors in TEE . . . . . . . . . . . . . . . . . . 7 4.3. Trust Anchors in TAM . . . . . . . . . . . . . . . . . . 7 4.4. Keys and Certificate Types . . . . . . . . . . . . . . . 7 5. Protocol Scope and Entity Relations . . . . . . . . . . . . . 10 5.1. A Sample Device Setup Flow . . . . . . . . . . . . . . . 12 5.2. Derived Keys in The Protocol . . . . . . . . . . . . . . 12 5.3. Security Domain Hierarchy and Ownership . . . . . . . . . 13 5.4. SD Owner Identification and TAM Certificate Requirements 13 5.5. Service Provider Container . . . . . . . . . . . . . . . 14 6. OTrP Broker . . . . . . . . . . . . . . . . . . . . . . . . . 15 6.1. Role of OTrP Broker . . . . . . . . . . . . . . . . . . . 15 6.2. OTrP Broker and Global Platform TEE Client API . . . . . 16 6.3. OTrP Broker Implementation Consideration . . . . . . . . 16 6.3.1. OTrP Broker Distribution . . . . . . . . . . . . . . 16 6.3.2. Number of OTrP Broker . . . . . . . . . . . . . . . . 16 6.4. OTrP Broker Interfaces for Client Applications . . . . . 17 6.4.1. ProcessOTrPMessage call . . . . . . . . . . . . . . . 17 6.4.2. GetTAInformation call . . . . . . . . . . . . . . . . 17 6.5. Sample End-to-End Client Application Flow . . . . . . . . 20 6.5.1. Case 1: A New Client Application Uses a TA . . . . . 20 6.5.2. Case 2: A Previously Installed Client Application Calls a TA . . . . . . . . . . . . . . . . . . . . . 21 7. OTrP Messages . . . . . . . . . . . . . . . . . . . . . . . . 22 7.1. Message Format . . . . . . . . . . . . . . . . . . . . . 22 7.2. Message Naming Convention . . . . . . . . . . . . . . . . 22 7.3. Request and Response Message Template . . . . . . . . . . 23 7.4. Signed Request and Response Message Structure . . . . . . 23 7.4.1. Identifying Signing and Encryption Keys for JWS/JWE Messaging . . . . . . . . . . . . . . . . . . . . . . 25 7.5. JSON Signing and Encryption Algorithms . . . . . . . . . 25 7.5.1. Supported JSON Signing Algorithms . . . . . . . . . . 27 Pei, et al. Expires April 26, 2019 [Page 2] Internet-Draft OTrP October 2018 7.5.2. Support JSON Encryption Algorithms . . . . . . . . . 27 7.5.3. Supported JSON Key Management Algorithms . . . . . . 27 7.6. Common Errors . . . . . . . . . . . . . . . . . . . . . . 28 7.7. OTrP Message List . . . . . . . . . . . . . . . . . . . . 28 7.8. OTrP Request Message Routing Rules . . . . . . . . . . . 29 7.8.1. SP Anonymous Attestation Key (SP AIK) . . . . . . . . 29 8. Transport Protocol Support . . . . . . . . . . . . . . . . . 29 9. Detailed Messages Specification . . . . . . . . . . . . . . . 30 9.1. GetDeviceState . . . . . . . . . . . . . . . . . . . . . 30 9.1.1. GetDeviceStateRequest message . . . . . . . . . . . . 30 9.1.2. Request processing requirements at a TEE . . . . . . 31 9.1.3. Firmware Signed Data . . . . . . . . . . . . . . . . 32 9.1.3.1. Supported Firmware Signature Methods . . . . . . 33 9.1.4. Post Conditions . . . . . . . . . . . . . . . . . . . 33 9.1.5. GetDeviceStateResponse Message . . . . . . . . . . . 33 9.1.6. Error Conditions . . . . . . . . . . . . . . . . . . 38 9.1.7. TAM Processing Requirements . . . . . . . . . . . . . 39 9.2. Security Domain Management . . . . . . . . . . . . . . . 40 9.2.1. CreateSD . . . . . . . . . . . . . . . . . . . . . . 40 9.2.1.1. CreateSDRequest Message . . . . . . . . . . . . . 40 9.2.1.2. Request Processing Requirements at a TEE . . . . 43 9.2.1.3. CreateSDResponse Message . . . . . . . . . . . . 44 9.2.1.4. Error Conditions . . . . . . . . . . . . . . . . 46 9.2.2. UpdateSD . . . . . . . . . . . . . . . . . . . . . . 46 9.2.2.1. UpdateSDRequest Message . . . . . . . . . . . . . 46 9.2.2.2. Request Processing Requirements at a TEE . . . . 49 9.2.2.3. UpdateSDResponse Message . . . . . . . . . . . . 51 9.2.2.4. Error Conditions . . . . . . . . . . . . . . . . 52 9.2.3. DeleteSD . . . . . . . . . . . . . . . . . . . . . . 53 9.2.3.1. DeleteSDRequest Message . . . . . . . . . . . . . 53 9.2.3.2. Request Processing Requirements at a TEE . . . . 55 9.2.3.3. DeleteSDResponse Message . . . . . . . . . . . . 56 9.2.3.4. Error Conditions . . . . . . . . . . . . . . . . 58 9.3. Trusted Application Management . . . . . . . . . . . . . 58 9.3.1. InstallTA . . . . . . . . . . . . . . . . . . . . . . 59 9.3.1.1. InstallTARequest Message . . . . . . . . . . . . 60 9.3.1.2. InstallTAResponse Message . . . . . . . . . . . . 62 9.3.1.3. Error Conditions . . . . . . . . . . . . . . . . 64 9.3.2. UpdateTA . . . . . . . . . . . . . . . . . . . . . . 64 9.3.2.1. UpdateTARequest Message . . . . . . . . . . . . . 65 9.3.2.2. UpdateTAResponse Message . . . . . . . . . . . . 67 9.3.2.3. Error Conditions . . . . . . . . . . . . . . . . 69 9.3.3. DeleteTA . . . . . . . . . . . . . . . . . . . . . . 69 9.3.3.1. DeleteTARequest Message . . . . . . . . . . . . . 69 9.3.3.2. Request Processing Requirements at a TEE . . . . 71 9.3.3.3. DeleteTAResponse Message . . . . . . . . . . . . 72 9.3.3.4. Error Conditions . . . . . . . . . . . . . . . . 73 10. Response Messages a TAM May Expect . . . . . . . . . . . . . 73 Pei, et al. Expires April 26, 2019 [Page 3] Internet-Draft OTrP October 2018 11. Basic Protocol Profile . . . . . . . . . . . . . . . . . . . 74 12. Attestation Implementation Consideration . . . . . . . . . . 75 12.1. OTrP Trusted Firmware . . . . . . . . . . . . . . . . . 75 12.1.1. Attestation signer . . . . . . . . . . . . . . . . . 75 12.1.2. TFW Initial Requirements . . . . . . . . . . . . . . 75 12.2. TEE Loading . . . . . . . . . . . . . . . . . . . . . . 76 12.3. Attestation Hierarchy . . . . . . . . . . . . . . . . . 76 12.3.1. Attestation Hierarchy Establishment: Manufacture . . 77 12.3.2. Attestation Hierarchy Establishment: Device Boot . . 77 12.3.3. Attestation Hierarchy Establishment: TAM . . . . . . 77 13. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 77 13.1. Error Code List . . . . . . . . . . . . . . . . . . . . 78 13.1.1. TEE Signed Error Code List . . . . . . . . . . . . . 78 13.1.2. OTrP Broker Error Code List . . . . . . . . . . . . 79 14. Security Consideration . . . . . . . . . . . . . . . . . . . 79 14.1. Cryptographic Strength . . . . . . . . . . . . . . . . . 79 14.2. Message Security . . . . . . . . . . . . . . . . . . . . 80 14.3. TEE Attestation . . . . . . . . . . . . . . . . . . . . 80 14.4. TA Protection . . . . . . . . . . . . . . . . . . . . . 80 14.5. TA Personalization Data . . . . . . . . . . . . . . . . 81 14.6. TA Trust Check at TEE . . . . . . . . . . . . . . . . . 81 14.7. One TA Multiple SP Case . . . . . . . . . . . . . . . . 82 14.8. OTrP Broker Trust Model . . . . . . . . . . . . . . . . 82 14.9. OCSP Stapling Data for TAM Signed Messages . . . . . . . 82 14.10. Data Protection at TAM and TEE . . . . . . . . . . . . . 82 14.11. Privacy Consideration . . . . . . . . . . . . . . . . . 82 14.12. Threat Mitigation . . . . . . . . . . . . . . . . . . . 83 14.13. Compromised CA . . . . . . . . . . . . . . . . . . . . . 83 14.14. Compromised TAM . . . . . . . . . . . . . . . . . . . . 84 14.15. Certificate Renewal . . . . . . . . . . . . . . . . . . 84 15. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 84 16. References . . . . . . . . . . . . . . . . . . . . . . . . . 84 16.1. Normative References . . . . . . . . . . . . . . . . . . 84 16.2. Informative References . . . . . . . . . . . . . . . . . 85 Appendix A. Sample Messages . . . . . . . . . . . . . . . . . . 85 A.1. Sample Security Domain Management Messages . . . . . . . 85 A.1.1. Sample GetDeviceState . . . . . . . . . . . . . . . . 85 A.1.1.1. Sample GetDeviceStateRequest . . . . . . . . . . 85 A.1.1.2. Sample GetDeviceStateResponse . . . . . . . . . . 86 A.1.2. Sample CreateSD . . . . . . . . . . . . . . . . . . . 89 A.1.2.1. Sample CreateSDRequest . . . . . . . . . . . . . 89 A.1.2.2. Sample CreateSDResponse . . . . . . . . . . . . . 92 A.1.3. Sample UpdateSD . . . . . . . . . . . . . . . . . . . 93 A.1.3.1. Sample UpdateSDRequest . . . . . . . . . . . . . 94 A.1.3.2. Sample UpdateSDResponse . . . . . . . . . . . . . 95 A.1.4. Sample DeleteSD . . . . . . . . . . . . . . . . . . . 95 A.1.4.1. Sample DeleteSDRequest . . . . . . . . . . . . . 95 A.1.4.2. Sample DeleteSDResponse . . . . . . . . . . . . . 97 Pei, et al. Expires April 26, 2019 [Page 4] Internet-Draft OTrP October 2018 A.2. Sample TA Management Messages . . . . . . . . . . . . . . 99 A.2.1. Sample InstallTA . . . . . . . . . . . . . . . . . . 99 A.2.1.1. Sample InstallTARequest . . . . . . . . . . . . . 99 A.2.1.2. Sample InstallTAResponse . . . . . . . . . . . . 100 A.2.2. Sample UpdateTA . . . . . . . . . . . . . . . . . . . 102 A.2.2.1. Sample UpdateTARequest . . . . . . . . . . . . . 102 A.2.2.2. Sample UpdateTAResponse . . . . . . . . . . . . . 103 A.2.3. Sample DeleteTA . . . . . . . . . . . . . . . . . . . 106 A.2.3.1. Sample DeleteTARequest . . . . . . . . . . . . . 106 A.2.3.2. Sample DeleteTAResponse . . . . . . . . . . . . . 108 A.3. Example OTrP Broker Option . . . . . . . . . . . . . . . 110 Appendix B. Contributors . . . . . . . . . . . . . . . . . . . . 110 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 110 1. Introduction The Trusted Execution Environment (TEE) concept has been designed to separate a regular operating system, also referred as a Rich Execution Environment (REE), from security-sensitive applications. In an TEE ecosystem, different device vendors may use different TEE implementations. Different application providers or device administrators may choose to use different TAM providers. There calls for an interoperable protocol for managing TAs running in different TEEs of various devices is needed. The Trusted Execution Environment Provisioning (TEEP) architecture document [TEEPArch] has set to provide a design guidance for such an interoperable protocol. This document specifies an Open Trust Protocol (OTrP) that follows the architecture guidance. OTrP defines a mutual trust message protocol between a TAM and a TEE and relies on IETF-defined end-to-end security mechanisms, namely JSON Web Encryption (JWE), JSON Web Signature (JWS), and JSON Web Key (JWK). Other message encoding methods may be supported. This specification defines message payloads exchanged between devices and a TAM. The messages are designed in anticipation of the use of the most common transport methods such as HTTPS. Each TA binary and configuration data can be from either of two sources: 1. A TAM supplies the signed and encrypted TA binary and any required configuration data 2. A Client Application supplies the TA binary Pei, et al. Expires April 26, 2019 [Page 5] Internet-Draft OTrP October 2018 This specification considers the first case where TA binary and configuration data are encrypted by recipient's public key that TAM has to be involved. The second case will also be addressed separately. 2. Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. 3. Terminology 3.1. Definitions The definitions provided below are defined as used in this document. All the terms defined in the TEEP Architecture document [TEEPArch] will be used, which are not repeated in this document. OTrP Broker: It is the Broker as defined in the TEEP Architecture document [TEEPArch]. 3.2. Abbreviations CA Certificate Authority OTrP Open Trust Protocol REE Rich Execution Environment SD Security Domain SP Service Provider TA Trusted Application TEE Trusted Execution Environment TFW Trusted Firmware TAM Trusted Application Manager 4. OTrP Entities and Trust Model Pei, et al. Expires April 26, 2019 [Page 6] Internet-Draft OTrP October 2018 4.1. System Components The same system components as defined in the TEEP Architecture document [TEEPArch] are used in OTrP, including TAM, CA, TEE, REE, and OTrP Broker (a.k.a Broker). Secure boot (for the purposes of OTrP) is optional in enabling authenticity checking of TEEs by the TAM. A TAM provider can choose it policy whether it trusts a TEE if the underlying firmware attestation information is not included. OTrP uses trust anchors to establish trust between TEEs and TAMs and verifies that they communicate in a trusted way when performing lifecycle management transactions. 4.2. Trust Anchors in TEE This assumes the Trust Anchor specification defined in the TEEP Architecture document [TEEPArch]. Each TEE comes with a trust store that contains a whitelist of root CA certificates that are used to validate a TAM's certificate. A TEE will accept a TAM to create new Security Domains and install new TAs on behalf of a SP only if the TAM's certificate is chained to one of the root CA certificates in the TEE's trust store. 4.3. Trust Anchors in TAM The Trust Anchor set in a TAM consists of a list of Certificate Authority certificates that signs various device TEE certificates. A TAM decides what TEE and optionally TFW it will trust when TFW signature data is present in an attestation. 4.4. Keys and Certificate Types OTrP leverages the following list of trust anchors and identities in generating signed and encrypted command messages that are exchanged between a device's TEE and a TAM. With these security artifacts, OTrP Messages are able to deliver end-to-end security without relying on any transport security. Pei, et al. Expires April 26, 2019 [Page 7] Internet-Draft OTrP October 2018 +-------------+----------+--------+-------------------+-------------+ | Key Entity | Location | Issuer | Trust Implication | Cardinality | | Name | | | | | +-------------+----------+--------+-------------------+-------------+ | 1. TFW key | Device | FW CA | A whitelist of FW | 1 per | | pair and | secure | | root CA trusted | device | | certificate | storage | | by TAMs | | | | | | | | | 2. TEE key | Device | TEE CA | A whitelist of | 1 per | | pair and | TEE | under | TEE root CA | device | | certificate | | a root | trusted by TAMs | | | | | CA | | | | | | | | | | 3. TAM key | TAM | TAM CA | A whitelist of | 1 or | | pair and | provider | under | TAM root CA | multiple | | certificate | | a root | embedded in TEE | can be used | | | | CA | | by a TAM | | | | | | | | 4. SP key | SP | SP | TAM manages SP. | 1 or | | pair and | | signer | TA trust is | multiple | | certificate | | CA | delegated to TAM. | can be used | | | | | TEE trusts TAM to | by a TAM | | | | | ensure that a TA | | | | | | is trustworthy. | | +-------------+----------+--------+-------------------+-------------+ Table 1: Key and Certificate Types 1. TFW key pair and certificate: A key pair and certificate for evidence of trustworthy firmware in a device. This key pair is optional. Some TEE may present its trusted attributes to a TAM using signed attestation with a TFW key. For example, a platform that uses a hardware based TEE can have attestation data signed by a hardware protected TFW key. Location: Device secure storage Supported Key Type: RSA and ECC Issuer: OEM CA Trust Implication: A whitelist of FW root CA trusted by TAMs Cardinality: One per device 2. TEE key pair and certificate: It is used for device attestation to a remote TAM and SP. Pei, et al. Expires April 26, 2019 [Page 8] Internet-Draft OTrP October 2018 This key pair is burned into the device at device manufacturer. The key pair and its certificate are valid for the expected lifetime of the device. Location: Device TEE Supported Key Type: RSA and ECC Issuer: A CA that chains to a TEE root CA Trust Implication: A whitelist of TEE root CA trusted by TAMs Cardinality: One per device 3. TAM key pair and certificate: A TAM provider acquires a certificate from a CA that a TEE trusts. Location: TAM provider Supported Key Type: RSA and ECC. Supported Key Size: RSA 2048-bit, ECC P-256 and P-384. Other sizes should be anticipated in future. Issuer: TAM CA that chains to a root CA Trust Implication: A whitelist of TAM root CA embedded in TEE Cardinality: One or multiple can be used by a TAM 4. SP key pair and certificate: an SP uses its own key pair and certificate to sign a TA. Location: SP Supported Key Type: RSA and ECC Supported Key Size: RSA 2048-bit, ECC P-256 and P-384. Other sizes should be anticipated in future. Issuer: an SP signer CA that chains to a root CA Trust Implication: TAM manages SP. TA trusts an SP by validating trust against a TAM that the SP uses. A TEE trusts TAM to ensure that a TA from the TAM is trustworthy. Cardinality: One or multiple can be used by an SP Pei, et al. Expires April 26, 2019 [Page 9] Internet-Draft OTrP October 2018 5. Protocol Scope and Entity Relations This document specifies messages and key properties that can establish mutual trust between a TEE and a TAM. The protocol provides specifications for the following three entities: 1. Key and certificate types required for device firmware, TEEs, TAs, SPs, and TAMs 2. Data message formats that should be exchanged between a TEE in a device and a TAM 3. An OTrP Broker in the REE that can relay messages between a Client Application and TEE Figure 1: Protocol Scope and Entity Relationship PKI CA -- CA CA -- | | | | | | | | | Device | | --- OTrP Broker / Client App --- | SW | | | | | | | | | | | | | | | OTrP | -- TEE TAM------- | | FW Figure 2: OTrP System Diagram Pei, et al. Expires April 26, 2019 [Page 10] Internet-Draft OTrP October 2018 -------OTrP Message Protocol--- | | | | -------------------- --------------- ---------- | REE | TEE | | TAM | | SP | | --- | --- | | --- | | -- | | | | | | | | | Client | SD (TAs)| | SD / TA | | TA | | Apps | | | Mgmt | | | | | | | | | | | | | | List of | | List of | | | | OTrP | Trusted | | Trusted | | | | Broker | TAM/SP | | FW/TEE | | | | | CAs | | CAs | | | | | | | | | | | |TEE Key/ | | TAM Key/ | | SP Key/| | | Cert | | Cert | | Cert | | | FW Key/ | | | | | | | Cert | | | | | -------------------- --------------- ---------- | | | | | | ------------- ---------- --------- | TEE CA | | TAM CA | | SP CA | ------------- ---------- --------- In the previous diagram, different Certificate Authorities can be used respectively for different types of certificates. OTrP Messages are always signed, where the signer keys is the message creator's private key such as a FW's private key, a TEE's private key, or a TAM's private key. The main OTrP component consists of a set of standard JSON messages created by a TAM to deliver device SD and TA management commands to a device, and device attestation and response messages created by a TEE that responds to a TAM's OTrP message. The communication method of OTrP Messages between a TAM and TEE in a device may vary between TAM and TEE providers. A mandatory transport protocol is specified for a compliant TAM and a device TEE. An OTrP Broker is used to bridge communication between a TAM and a TEE. The OTrP Broker doesn't need to know the actual content of OTrP Messages except for the TEE routing information. Pei, et al. Expires April 26, 2019 [Page 11] Internet-Draft OTrP October 2018 5.1. A Sample Device Setup Flow Step 1: Prepare Images for Devices 1. [TEE vendor] Deliver TEE Image (CODE Binary) to device OEM 2. [CA] Deliver root CA Whitelist 3. [Soc] Deliver TFW Image Step 2: Inject Key Pairs and Images to Devices 1. [OEM] Generate Secure Boot Key Pair (May be shared among multiple devices) 2. [OEM] Flash signed TFW Image and signed TEE Image onto devices (signed by Secure Boot Key) Step 3: Setup attestation key pairs in devices 1. [OEM] Flash TFW Public Key and a bootloader key. 2. [TFW/TEE] Generate a unique attestation key pair and get a certificate for the device. Step 4: Setup trust anchors in devices 1. [TFW/TEE] Store the key and certificate encrypted with the eFuse key 2. [TEE vendor or OEM] Store trusted CA certificate list into devices 5.2. Derived Keys in The Protocol The protocol generates one key pair in run time to assist message communication and anonymous verification between a TAM and a TEE. TEE SP Anonymous Key (AIK): one derived key pair per SP in a device The purpose of the key pair is to sign data by a TEE without using its TEE device key for anonymous attestation to a Client Application. This key pair is generated in the first SD creation for an SP. It is deleted when all SDs are removed for a SP in a device. The public key of the key pair is given to the caller Client Application and TAM for future TEE returned data validation. The public key of this AIK is also used by a TAM to encrypt TA binary data and personalization data when it sends a TA to a device for installation. Pei, et al. Expires April 26, 2019 [Page 12] Internet-Draft OTrP October 2018 5.3. Security Domain Hierarchy and Ownership The primary job of a TAM is to help an SP to manage its trusted application components. A TA is typically installed in an SD. An SD is commonly created for an SP. When an SP delegates its SD and TA management to a TAM, an SD is created on behalf of a TAM in a TEE and the owner of the SD is assigned to the TAM. An SD may be associated with an SP but the TAM has full privilege to manage the SD for the SP. Each SD for an SP is associated with only one TAM. When an SP changes TAM, a new SP SD must be created to associate with the new TAM. The TEE will maintain a registry of TAM ID and SP SD ID mapping. From an SD ownership perspective, the SD tree is flat and there is only one level. An SD is associated with its owner. It is up to TEE implementation how it maintains SD binding information for a TAM and different SPs under the same TAM. It is an important decision in this protocol specification that a TEE doesn't need to know whether a TAM is authorized to manage the SD for an SP. This authorization is implicitly triggered by an SP Client Application, which instructs what TAM it wants to use. An SD is always associated with a TAM in addition to its SP ID. A rogue TAM isn't able to do anything on an unauthorized SP's SD managed by another TAM. Since a TAM may support multiple SPs, sharing the same SD name for different SPs creates a dependency in deleting an SD. An SD can be deleted only after all TAs associated with this SD is deleted. An SP cannot delete a Security Domain on its own with a TAM if a TAM decides to introduce such sharing. There are cases where multiple virtual SPs belong to the same organization, and a TAM chooses to use the same SD name for those SPs. This is totally up to the TAM implementation and out of scope of this specification. 5.4. SD Owner Identification and TAM Certificate Requirements There is a need of cryptographically binding proof about the owner of an SD in a device. When an SD is created on behalf of a TAM, a future request from the TAM must present itself as a way that the TEE can verify it is the true owner. The certificate itself cannot reliably used as the owner because TAM may change its certificate. To this end, each TAM will be associated with a trusted identifier defined as an attribute in the TAM certificate. This field is kept Pei, et al. Expires April 26, 2019 [Page 13] Internet-Draft OTrP October 2018 the same when the TAM renew its certificates. A TAM CA is responsible to vet the requested TAM attribute value. This identifier value must not collide among different TAM providers, and one TAM shouldn't be able to claim the identifier used by another TAM provider. The certificate extension name to carry the identifier can initially use SubjectAltName:registeredID. A dedicated new extension name may be registered later. One common choice of the identifier value is the TAM's service URL. A CA can verify the domain ownership of the URL with the TAM in the certificate enrollment process. A TEE can assign this certificate attribute value as the TAM owner ID for the SDs that are created for the TAM. An alternative way to represent an SD ownership by a TAM is to have a unique secret key upon SD creation such that only the creator TAM is able to produce a Proof-of-Possession (POP) data with the secret. 5.5. Service Provider Container A sample Security Domain hierarchy for the TEE is shown below. ---------- | TEE | ---------- | | ---------- |----------| SP1 SD1 | | ---------- | ---------- |----------| SP1 SD2 | | ---------- | ---------- |----------| SP2 SD1 | ---------- OTrP segregates SDs and TAs such that a TAM can only manage or retrieve data for SDs and TAs that it previously created for the SPs it represents. Pei, et al. Expires April 26, 2019 [Page 14] Internet-Draft OTrP October 2018 6. OTrP Broker A TEE and TAs that run inside the TEE don't generally have capability to communicate to the outside of the hosting device, for example, the TEE specified by Global Platform groups [GPTEE]. This calls for a software module in the REE world to handle the network communication. Each Client Application in REE may carry this communication functionality but it must also interact with the TEE for the message exchange. The TEE interaction will vary according to different TEEs. In order for a Client Application to transparently support different TEEs, it is imperative to have a common interface for a Client Application to invoke for exchanging messages with TEEs. A shared OTrP Broker comes to meed this need. An OTrP Broker is a Rich Application or SDK that facilitates communication between a TAM and TEE. It also provides interfaces for TAM SDK or Client Applications to query and trigger TA installation that the application needs to use. This interface for Client Applications may be commonly an Android service call for an Android powered device. A Client Application interacts with a TAM, and turns around to pass messages received from TAM to OTrP Broker. In all cases, a Client Application needs to be able to identify an OTrP Broker that it can use. 6.1. Role of OTrP Broker An OTrP Broker abstracts the message exchanges with the TEE in a device. The input data is originated from a TAM that a Client Application connects. A Client Application may also directly call OTrP Broker for some TA query functions. OTrP Broker may internally process a request from TAM. At least, it needs to know where to route a message, e.g. TEE instance. It doesn't need to process or verify message content. OTrP Broker returns TEE / TFW generated response messages to the caller. OTrP Broker isn't expected to handle any network connection with an application or TAM. OTrP Broker only needs to return an OTrP Broker error message if the TEE is not reachable for some reason. Other errors are represented as response messages returned from the TEE which will then be passed to the TAM. Pei, et al. Expires April 26, 2019 [Page 15] Internet-Draft OTrP October 2018 6.2. OTrP Broker and Global Platform TEE Client API A Client Application may use Global Platform (GP) TEE API for TA communication. OTrP may use the GP TEE Client API but it is internal to OTrP implementation that converts given messages from TAM. More details can be found at [GPTEECLAPI]. 6.3. OTrP Broker Implementation Consideration A Provider should consider methods of distribution, scope and concurrency on device and runtime options when implementing an OTrP Broker. Several non-exhaustive options are discussed below. Providers are encouraged to take advantage of the latest communication and platform capabilities to offer the best user experience. 6.3.1. OTrP Broker Distribution OTrP Broker installation is commonly carried out at OEM time. A user can dynamically download and install an OTrP Broker on-demand. It is important to ensure a legitimate OTrP Broker is installed and used. If an OTrP Broker is compromised it may send rogue messages to TAM and TEE and introduce additional risks. 6.3.2. Number of OTrP Broker We anticipate only one shared OTrP Broker instance in a device. The device's TEE vendor will most probably supply one OTrP Broker. Potentially we expect some open source. With one shared OTrP Broker, the OTrP Broker provider is responsible to allow multiple TAMs and TEE providers to achieve interoperability. With a standard OTrP Broker interface, TAM can implement its own SDK for its SP Client Applications to work with this OTrP Broker. Multiple independent OTrP Broker providers can be used as long as they have standard interface to a Client Application or TAM SDK. Only one OTrP Broker is expected in a device. TAM providers are generally expected to provide SDK for SP applications to interact with an OTrP Broker for the TAM and TEE interaction. Pei, et al. Expires April 26, 2019 [Page 16] Internet-Draft OTrP October 2018 6.4. OTrP Broker Interfaces for Client Applications A Client Application shall be responsible for relaying messages between the OTrP Broker and the TAM. If a failure occurs during calling OTrP Broker, an error message described in "Common Errors" section (see Section 7.6) will be returned. 6.4.1. ProcessOTrPMessage call Description A Client Application will use this method of the OTrP Broker in a device to pass OTrP messages from a TAM. The method is responsible for interacting with the TEE and for forwarding the input message to the TEE. It also returns TEE generated response message back to the Client Application. Inputs: TAMInMsg - OTrP message generated in a TAM that is passed to this method from a Client Application. Outputs: A TEE-generated OTrP response message (which may be a successful response or be a response message containing an error raised within the TEE) for the client application to forward to the TAM. In the event of the OTrP Broker not being able to communicate with the TEE, a OTrPBrokerException shall be thrown. 6.4.2. GetTAInformation call Description A Client Application may quickly query local TEE about a previously installed TA without requiring TAM each time if it has had the TA's identifier and previously saved TEE SP AIK public key for TA information integrity verification. Inputs: Pei, et al. Expires April 26, 2019 [Page 17] Internet-Draft OTrP October 2018 { "TAQuery": { "spid": "", "taid": "" } } Outputs: The OTrP Broker is expected to return TA signer and TAM signer certificate along with other metadata information about the TA associated with the given identifier. It follows the underlying TEE trust model for authoring the local TA query from a Client Application. The output is a JSON message that is generated by the TEE. It contains the following information: * tamid * SP ID * TA signer certificate * TAM certificate The message is signed with TEE SP AIK private key. The Client Application is expected to consume the response as follows. The Client Application gets signed TA metadata, in particular, the TA signer certificate. It is able to verify that the result is from device by checking signer against TEE SP AIK public key it gets in some earlier interaction with TAM. If this is a new Client Application in the device that hasn't had TEE SP AIK public key for the response verification, the application can contact the TAM first to do GetDeviceState, and TAM will return TEE SP AIK public key to the app for this operation to proceed. Output Message: Pei, et al. Expires April 26, 2019 [Page 18] Internet-Draft OTrP October 2018 { "TAInformationTBS": { "taid": "", "tamid": "", "spid": "", "signercert": "", "signercacerts": [ < The full list of CA certificate chain including the root CA> ], "cacert": "" ], "tamcert": "", "tamcacerts": [ < The full list of CA certificate chain including the root CA> ], "cacert":"" ] } } { "TAInformation": { "payload": "", "protected": "", "header": { "signer": {""} }, "signature": "" } } where the definitions of BASE64 and BASE64URL refer to [RFC4648]. A sample JWK public key representation refers to an example in [RFC7517]. Pei, et al. Expires April 26, 2019 [Page 19] Internet-Draft OTrP October 2018 6.5. Sample End-to-End Client Application Flow 6.5.1. Case 1: A New Client Application Uses a TA 1. During the Client Application installation time, the Client Application calls TAM to initialize the device preparation step. A. The Client Application knows it wants to use a Trusted Application TA1 but the application doesn't know whether TA1 has been installed or not. It can use GP TEE Client API [GPTEECLAPI] to check the existence of TA1 first. If it detects that TA1 doesn't exist, it will contact TAM to initiate the installation of TA1. Note that TA1 could have been previously installed by other Client Applications from the same service provider in the device. B. The Client Application sends the TAM the TA list that it depends on. The TAM will query a device for the Security Domains and TAs that have been installed, and instructs the device to install any dependent TAs that have not been installed. C. In general, the TAM has the latest TA list and their status in a device because all operations are instructed by TAM. TAM has such visibility because all Security Domain deletion and TA deletion are managed by the TAM; the TAM could have stored the state when a TA is installed, updated and deleted. There is also the possibility that an update command is carried out inside TEE but a response is never received in TAM. There is also possibility that some manual local reset is done in a device that the TAM isn't aware of the changes. 2. The TAM generates message: GetDeviceStateRequest 3. The Client Application passes the JSON message GetDeviceStateRequest to OTrP Broker call ProcessOTrPMessage. The communication between a Client Application and an OTrP Broker is up to the implementation of the OTrP Broker. 4. The OTrP Broker routes the message to the active TEE. Multiple TEE case: it is up to OTrP Broker to figure this out. This specification limits the support to only one active TEE, which is the typical case today. 5. The target active TEE processes the received OTrP message, and returns a JSON message GetDeviceStateResponse. Pei, et al. Expires April 26, 2019 [Page 20] Internet-Draft OTrP October 2018 6. The OTrP Broker passes the GetDeviceStateResponse to the Client Application. 7. The Client Application sends GetDeviceStateResponse to the TAM. 8. The TAM processes the GetDeviceStateResponse. A. Extract TEEspaik for the SP, signs TEEspaik with TAM signer key B. Examine SD list and TA list 9. The TAM continues to carry out other actions based on the need. The next call could be instructing the device to install a dependent TA. A. Assume a dependent TA isn't in the device yet, the TAM may do the following: (1) create an SD in which to install the TA by sending a CreateSDRequest message. The message is sent back to the Client Application, and then the OTrP Broker and TEE to process; (2) install a TA with an InstallTARequest message. B. If a Client Application depends on multiple TAs, the Client Application should expect multiple round trips of the TA installation message exchanges. 10. At the last TAM and TEE operation, the TAM returns the signed TEE SP AIK public key to the application. 11. The Client Application stores the TEEspaik for future loaded TA trust check. 12. If the TAM finds that this is a fresh device that does not have any SD for the SP yet, then the TAM may next create an SD for the SP. 13. During Client Application installation, the application checks whether required Trusted Applications are already installed, which may have been provided by the TEE. If needed, it will contact its TAM service to determine whether the device is ready or install TA list that this application needs. 6.5.2. Case 2: A Previously Installed Client Application Calls a TA 1. The Client Application checks the device readiness: (a) whether it has a TEE; (b) whether it has TA that it depends. It may happen that TAM has removed the TA this application depends on. Pei, et al. Expires April 26, 2019 [Page 21] Internet-Draft OTrP October 2018 2. The Client Application calls the OTrP Broker to query the TA. 3. The OTrP Broker queries the TEE to get TA information. If the given TA doesn't exist, an error is returned. 4. The Client Application parses the TAInformation message. 5. If the TA doesn't exist, the Client Application calls its TAM to install the TA. If the TA exists, the Client Application proceeds to call the TA. 7. OTrP Messages The main OTrP component is the set of standard JSON messages created by a TAM to deliver device SD and TA management commands to a device, and device attestation and response messages created by TEE to respond to TAM OTrP Messages. An OTrP Message is designed to provide end-to-end security. It is always signed by its creator. In addition, an OTrP Message is typically encrypted such that only the targeted device TEE or TAM is able to decrypt and view the actual content. 7.1. Message Format OTrP Messages use the JSON format for JSON's simple readability and moderate data size in comparison with alternative TLV and XML formats. More compact CBOR format may be used as an alternative choice. JSON Message security has developed JSON Web Signing and JSON Web Encryption standard in the IETF Workgroup JOSE, see JWS [RFC7515] and JWE [RFC7516]. The OTrP Messages in this protocol will leverage the basic JWS and JWE to handle JSON signing and encryption. 7.2. Message Naming Convention For each TAM command "xyz"", OTrP use the following naming convention to represent its raw message content and complete request and response messages: Pei, et al. Expires April 26, 2019 [Page 22] Internet-Draft OTrP October 2018 +-----------------------+----------------+---------------------+ | Purpose | Message Name | Example | +-----------------------+----------------+---------------------+ | Request to be signed | xyzTBSRequest | CreateSDTBSRequest | | | | | | Request message | xyzRequest | CreateSDRequest | | | | | | Response to be signed | xyzTBSResponse | CreateSDTBSResponse | | | | | | Response message | xyzResponse | CreateSDResponse | +-----------------------+----------------+---------------------+ 7.3. Request and Response Message Template An OTrP Request message uses the following format: { "TBSRequest": { } } A corresponding OTrP Response message will be as follows. { "TBSResponse": { } } 7.4. Signed Request and Response Message Structure A signed request message will generally include only one signature, and uses the flattened JWS JSON Serialization Syntax, see Section 7.2.2 in [RFC7515]. A general JWS object looks like the following. { "payload": "", "protected": "", "header": { , }, "signature": "" } Pei, et al. Expires April 26, 2019 [Page 23] Internet-Draft OTrP October 2018 OTrP signed messages only require the signing algorithm as the mandate header in the property "protected". The "non-integrity- protected header contents" is optional. OTrP signed message will be given an explicit Request or Response property name. In other words, a signed Request or Response uses the following template. A general JWS object looks like the following. { "[Request | Response]": { TBS[Request | Response] } } With the standard JWS message format, a signed OTrP Message looks like the following. { "[Request | Response]": { "payload": "TBS[Request | Response]>", "protected": "", "header": , "signature": "" } } The top element "[Signed][Request|Response]" cannot be fully trusted to match the content because it doesn't participate in the signature generation. However, a recipient can always match it with the value associated with the property "payload". It purely serves to provide a quick reference for reading and method invocation. Furthermore, most properties in an unsigned OTrP messages are encrypted to provide end-to-end confidentiality. The only OTrP message that isn't encrypted is the initial device query message that asks for the device state information. Thus a typical OTrP Message consists of an encrypted and then signed JSON message. Some transaction data such as transaction ID and TEE information may need to be exposed to the OTrP Broker for routing purpose. Such information is excluded from JSON encryption. The device's signer certificate itself is encrypted. The overall final message is a standard signed JSON message. As required by JSW/JWE, those JWE and JWS related elements will be BASE64URL encoded. Other binary data elements specific to the OTrP Pei, et al. Expires April 26, 2019 [Page 24] Internet-Draft OTrP October 2018 specification are BASE64-encoded. This specification indicates elements that should be BASE64 and those elements that are to be BASE64URL encoded. 7.4.1. Identifying Signing and Encryption Keys for JWS/JWE Messaging JWS and JWE messaging allow various options for identifying the signing and encryption keys, for example, it allows optional elements including "x5c", "x5t" and "kid" in the header to cover various possibilities. To protect privacy, it is important that the device's certificate is released only to a trusted TAM, and that it is encrypted. The TAM will need to know the device certificate, but untrusted parties must not be able to get the device certificate. All OTrP messaging conversations between a TAM and device begin with GetDeviceStateRequest / GetDeviceStateResponse. These messages have elements built into them to exchange signing certificates, described in the section Section 9. Any subsequent messages in the conversation that follow on from this implicitly use the same certificates for signing/encryption, and as a result the certificates or references may be omitted in those subsequent messages. In other words, the signing key identifier in the use of JWS and JWE here may be absent in the subsequent messages after the initial GetDeviceState query. This has an implication on the TEE and TAM implementation: they have to cache the signer certificates for the subsequent message signature validation in the session. It may be easier for a TAM service to cache transaction session information but not so for a TEE in a device. A TAM can get a device's capability by checking the response message from a TEE to decide whether it should include its TAM signer certificate and OCSP data in each subsequent request message. The device's caching capability is reported in GetDeviceStateResponse signerreq parameter. 7.5. JSON Signing and Encryption Algorithms The OTrP JSON signing algorithm shall use SHA256 or a stronger hash method with respective key type. JSON Web Algorithm RS256 or ES256 [RFC7518] SHALL be used for RSA with SHA256 and ECDSA with SHA256. If RSA with SHA256 is used, the JSON web algorithm representation is as follows. {"alg":"RS256"} Pei, et al. Expires April 26, 2019 [Page 25] Internet-Draft OTrP October 2018 The (BASE64URL encoded) "protected" header property in a signed message looks like the following: "protected":"eyJhbGciOiJSUzI1NiJ9" If ECSDA with P-256 curve and SHA256 are used for signing, the JSON signing algorithm representation is as follows. {"alg":"ES256"} The value for the "protected" field will be the following. eyJhbGciOiJFUzI1NiJ9 Thus, a common OTrP signed message with ES256 looks like the following. { "payload": "", "protected": "eyJhbGciOiJFUzI1NiJ9", "signature": "" } The OTrP JSON message encryption algorithm SHOULD use one of the supported algorithms defined in the later chapter of this document. JSON encryption uses a symmetric key as its "Content Encryption Key (CEK)". This CEK is encrypted or wrapped by a recipient's key. The OTrP recipient typically has an asymmetric key pair. Therefore, the CEK will be encrypted by the recipient's public key. A compliant implementation shall support the following symmetric encryption algorithm and anticipate future new algorithms. {"enc":"A128CBC-HS256"} This algorithm represents encryption with AES 128 in CBC mode with HMAC SHA 256 for integrity. The value of the property "protected" in a JWE message will be eyJlbmMiOiJBMTI4Q0JDLUhTMjU2In0 Pei, et al. Expires April 26, 2019 [Page 26] Internet-Draft OTrP October 2018 An encrypted JSON message looks like the following. { "protected": "eyJlbmMiOiJBMTI4Q0JDLUhTMjU2In0", "recipients": [ { "header": { "alg": "" }, "encrypted_key": "" } ], "iv": "", "ciphertext": "", "tag": "" } OTrP doesn't use JWE AAD (Additional Authenticated Data) because each message is always signed after the message is encrypted. 7.5.1. Supported JSON Signing Algorithms The following JSON signature algorithm is mandatory support in the TEE and TAM: o RS256 ES256 is optional to support. 7.5.2. Support JSON Encryption Algorithms The following JSON authenticated encryption algorithm is mandatory support in TEE and TAM. o A128CBC-HS256 A256CBC-HS512 is optional to support. 7.5.3. Supported JSON Key Management Algorithms The following JSON key management algorithm is mandatory support in TEE and TAM. o RSA1_5 ECDH-ES+A128KW and ECDH-ES+A256KW are optional to support. Pei, et al. Expires April 26, 2019 [Page 27] Internet-Draft OTrP October 2018 7.6. Common Errors An OTrP Response message typically needs to report the operation status and error causes if an operation fails. The following JSON message elements should be used across all OTrP Messages. "status": "pass | fail" "reason": { "error-code": "", "error-message": "" } "ver": "" 7.7. OTrP Message List The following table lists the OTrP commands and therefore corresponding Request and Response messages defined in this specification. Additional messages may be added in the future when new task messages are needed. GetDeviceState - A TAM queries a device's current state with a message GetDeviceStateRequest. A device TEE will report its version, its FW version, and list of all SDs and TAs in the device that is managed by the requesting TAM. TAM may determine whether the device is trustworthy and decide to carry out additional commands according to the response from this query. CreateSD - A TAM instructs a device TEE to create an SD for an SP. The recipient TEE will check whether the requesting TAM is trustworthy. UpdateSD - A TAM instructs a device TEE to update an existing SD. A typical update need comes from SP certificate change, TAM certificate change and so on. The recipient TEE will verify whether the TAM is trustworthy and owns the SD. DeleteSD - A TAM instructs a device TEE to delete an existing SD. A TEE conditionally deletes TAs loaded in the SD according to a request parameter. An SD cannot be deleted until all TAs in this SD are deleted. If this is the last SD for an SP, TEE MAY also delete TEE SP AIK key for this SP. Pei, et al. Expires April 26, 2019 [Page 28] Internet-Draft OTrP October 2018 InstallTA - A TAM instructs a device to install a TA into an SD for a SP. The TEE in a device will check whether the TAM and TA are trustworthy. UpdateTA - A TAM instructs a device to update a TA into an SD for an SP. The change may commonly be bug fix for a previously installed TA. DeleteTA - A TAM instructs a device to delete a TA. The TEE in a device will check whether the TAM and TA are trustworthy. 7.8. OTrP Request Message Routing Rules For each command that a TAM wants to send to a device, the TAM generates a request message. This is typically triggered by a Client Application that uses the TAM. The Client Application initiates contact with the TAM and receives TAM OTrP Request messages according to the TAM's implementation. The Client Application forwards the OTrP message to an OTrP Broker in the device, which in turn sends the message to the active TEE in the device. The current version of this specification assumes that each device has only one active TEE, and the OTrP Broker is responsible to connect to the active TEE. This is the case today with devices in the market. When the TEE responds to a request, the OTrP Broker gets the OTrP response messages back to the Client Application that sent the request. In case the target TEE fails to respond to the request, the OTrP Broker will be responsible to generate an error message to reply the Client Application. The Client Application forwards any data it received to its TAM. 7.8.1. SP Anonymous Attestation Key (SP AIK) When the first new Security Domain is created in a TEE for an SP, a new key pair is generated and associated with this SP. This key pair is used for future device attestation to the service provider instead of using the device's TEE key pair. 8. Transport Protocol Support The OTrP message exchange between a TEE device and TAM generally takes place between a Client Application in REE and TAM. A device that is capable to run a TEE and PKI based cryptographic attestation Pei, et al. Expires April 26, 2019 [Page 29] Internet-Draft OTrP October 2018 isn't generally resource constraint to carry out standard HTTPS connections. A compliant device and TAM SHOULD support HTTPs. 9. Detailed Messages Specification For each message in the following sections all JSON elements are mandatory if not explicitly indicated as optional. 9.1. GetDeviceState This is the first command that a TAM will send to a device. This command is triggered when an SP's Client Application contacts its TAM to check whether the underlying device is ready for TA operations. This command queries a device's current TEE state. A device TEE will report its version, its FW version, and list of all SDs and TAs in the device that is managed by the requesting TAM. TAM may determine whether the device is trustworthy and decide to carry out additional commands according to the response from this query. The request message of this command is signed by the TAM. The response message from the TEE is encrypted. A random message encryption key (MK) is generated by TEE, and this encrypted key is encrypted by the TAM's public key such that only the TAM that sent the request is able to decrypt and view the response message. 9.1.1. GetDeviceStateRequest message { "GetDeviceStateTBSRequest": { "ver": "1.0", "rid": "", "tid": "", "ocspdat": ["], "supportedsigalgs": [] } } The request message consists of the following data elements: ver - version of the message format rid - a unique request ID generated by the TAM tid - a unique transaction ID to trace request and response. This can be from a prior transaction's tid field, and can be used in subsequent message exchanges in this TAM session. The combination of rid and tid MUST be made unique. Pei, et al. Expires April 26, 2019 [Page 30] Internet-Draft OTrP October 2018 ocspdat - A list of OCSP stapling data respectively for the TAM certificate and each of the CA certificates up to the root certificate. The TAM provides OCSP data such that a recipient TEE can validate the TAM certificate chain revocation status without making its own external OCSP service call. A TEE MAY cache the CA OCSP data such that the array may contain only the OCSP stapling data for the TAM certificate in subsequent exchanges. This is a mandatory field. supportedsigalgs - an optional property to list the signing algorithms that the TAM is able to support. A recipient TEE MUST choose an algorithm in this list to sign its response message if this property is present in a request. If it is absent, the TEE may use any compliant signing algorithm that is listed as mandatory support in this specification. The final request message is JSON signed message of the above raw JSON data with TAM's certificate. { "GetDeviceStateRequest": { "payload": "", "protected": "", "header": { "x5c": "" }, "signature":"" } } The signing algorithm SHOULD use SHA256 with respective key type. The mandatory algorithm support is the RSA signing algorithm. The signer header "x5c" is used to include the TAM signer certificate up to the root CA certificate. 9.1.2. Request processing requirements at a TEE Upon receiving a request message GetDeviceStateRequest at a TEE, the TEE MUST validate a request: 1. Validate JSON message signing. If it doesn't pass, an error message is returned. 2. Validate that the request TAM certificate is chained to a trusted CA that the TEE embeds as its trust anchor. Pei, et al. Expires April 26, 2019 [Page 31] Internet-Draft OTrP October 2018 * Cache the CA OCSP stapling data and certificate revocation check status for other subsequent requests. * A TEE can use its own clock time for the OCSP stapling data validation. 3. Optionally collect Firmware signed data * This is a capability in ARM architecture that allows a TEE to query Firmware to get FW signed data. It isn't required for all TEE implementations. When TFW signed data is absent, it is up to a TAM's policy how it will trust a TEE. 4. Collect SD information for the SD owned by this TAM 9.1.3. Firmware Signed Data Firmware isn't expected to process or produce JSON data. It is expected to just sign some raw bytes of data. The data to be signed by TFW key needs be some unique random data each time. The (UTF-8 encoded) "tid" value from the GetDeviceStateTBSRequest shall be signed by the firmware. TAM isn't expected to parse TFW data except the signature validation and signer trust path validation. It is possible that a TEE can get some valid TFW signed data from another device. The TEE is responsible to validate TFW integrity to ensure that the underlying device firmware is trustworthy. In some cases, a TEE isn't able to get a TFW signed data, in which case the TEE trust validation is up to a TAM to decide. A TAM may opt to trust a TEE basing on the TEE signer and additional information about a TEE out-of-band. When TFW signed data is available, a TAM validates the TEE and trusts that a trusted TEE has carried out appropriate trust check about a TFW. TfwData: { "tbs": "", "cert": "", "sigalg": "Signing method", "sig": "" } It is expected that a FW uses standard signature methods for maximal interoperability with TAM providers. The mandatory support list of signing algorithm is RSA with SHA256. Pei, et al. Expires April 26, 2019 [Page 32] Internet-Draft OTrP October 2018 The JSON object above is constructed by a TEE with data returned from the FW. It isn't a standard JSON signed object. The signer information and data to be signed must be specially processed by a TAM according to the definition given here. The data to be signed is the raw data. 9.1.3.1. Supported Firmware Signature Methods TAM providers shall support the following signature methods. A firmware provider can choose one of the methods in signature generation. o RSA with SHA256 o ECDSA with SHA 256 The value of "sigalg" in the TfwData JSON message SHOULD use one of the following: o RS256 o ES256 9.1.4. Post Conditions Upon successful request validation, the TEE information is collected. There is no change in the TEE in the device. The response message shall be encrypted where the encryption key shall be a symmetric key that is wrapped by TAM's public key. The JSON Content Encryption Key (CEK) is used for this purpose. 9.1.5. GetDeviceStateResponse Message The message has the following structure. { "GetDeviceTEEStateTBSResponse": { "ver": "1.0", "status": "pass | fail", "rid": "", "tid": "", "signerreq": true | false // about whether TAM needs to send signer data again in subsequent messages, "edsi": "" } } Pei, et al. Expires April 26, 2019 [Page 33] Internet-Draft OTrP October 2018 where signerreq - true if the TAM should send its signer certificate and OCSP data again in the subsequent messages. The value may be "false" if the TEE caches the TAM's signer certificate and OCSP status. rid - the request ID from the request message tid - the tid from the request message edsi - the main data element whose value is JSON encrypted message over the following Device State Information (DSI). The Device State Information (DSI) message consists of the following. Pei, et al. Expires April 26, 2019 [Page 34] Internet-Draft OTrP October 2018 { "dsi": { "tfwdata": { "tbs": "" "cert": "", "sigalg": "Signing method", "sig": "" }, "tee": { "name": "", "ver": "", "cert": "", "cacert": "", "sdlist": { "cnt": "", "sd": [ { "name": "", "spid": "", "talist": [ { "taid": "", "taname": "" // optional } ] } ] }, "teeaiklist": [ { "spaik": "", "spaiktype": "", "spid": "" } ] } } } The encrypted JSON message looks like the following. Pei, et al. Expires April 26, 2019 [Page 35] Internet-Draft OTrP October 2018 { "protected": "", "recipients": [ { "header": { "alg": "RSA1_5" }, "encrypted_key": "" } ], "iv": "", "ciphertext": "", "tag": "" } Assume we encrypt plaintext with AES 128 in CBC mode with HMAC SHA 256 for integrity, the encryption algorithm header is: {"enc":"A128CBC-HS256"} The value of the property "protected" in the above JWE message will be eyJlbmMiOiJBMTI4Q0JDLUhTMjU2In0 In other words, the above message looks like the following: { "protected": "eyJlbmMiOiJBMTI4Q0JDLUhTMjU2In0", "recipients": [ { "header": { "alg": "RSA1_5" }, "encrypted_key": "" } ], "iv": "", "ciphertext": "", "tag": "" } The full response message looks like the following: Pei, et al. Expires April 26, 2019 [Page 36] Internet-Draft OTrP October 2018 { "GetDeviceTEEStateTBSResponse": { "ver": "1.0", "status": "pass | fail", "rid": "", "tid": "", "signerreq": "true | false", "edsi": { "protected": "", "recipients": [ { "header": { "alg": "RSA1_5" }, "encrypted_key": "" } ], "iv": "", "ciphertext": "", "tag": "" } } } The CEK will be encrypted by the TAM public key in the device. The TEE signed message has the following structure. { "GetDeviceTEEStateResponse": { "payload": "", "protected": "", "signature": "" } } The signing algorithm shall use SHA256 with respective key type, see Section 7.5.1. The final GetDeviceStateResponse response message consists of an array of TEE responses. Pei, et al. Expires April 26, 2019 [Page 37] Internet-Draft OTrP October 2018 { "GetDeviceStateResponse": [ // JSON array {"GetDeviceTEEStateResponse": ...}, ... {"GetDeviceTEEStateResponse": ...} ] } 9.1.6. Error Conditions An error may occur if a request isn't valid or the TEE runs into some error. The list of possible error conditions is the following. ERR_REQUEST_INVALID The TEE meets the following conditions with a request message: (1) The request from a TAM has an invalid message structure; mandatory information is absent in the message; or an undefined member or structure is included. (2) TEE fails to verify the signature of the message or fails to decrypt its contents. ERR_UNSUPPORTED_MSG_VERSION The TEE receives a version of message that the TEE can't deal with. ERR_UNSUPPORTED_CRYPTO_ALG The TEE receives a request message encoded with a cryptographic algorithm that the TEE doesn't support. ERR_TFW_NOT_TRUSTED The TEE considers the underlying device firmware be not trustworthy. ERR_TAM_NOT_TRUSTED The TEE needs to make sure whether the TAM is trustworthy by checking the validity of the TAM certificate and OCSP stapling data and so on. If the TEE finds the TAM is not reliable, it returns this error code. ERR_TEE_FAIL If the TEE fails to process a request because of its internal error but is able to sign an error response message, it will return this error code. ERR_AGENT_TEE_FAIL The TEE failed to respond to a TAM request. The OTrP Broker will construct an error message in responding to the TAM's request. The error message will not be signed. The response message will look like the following if the TEE signing can work to sign the error response message. Pei, et al. Expires April 26, 2019 [Page 38] Internet-Draft OTrP October 2018 { "GetDeviceTEEStateTBSResponse": { "ver": "1.0", "status": "fail", "rid": "", "tid": "", "reason": {"error-code":""} "supportedsigalgs": [] } } where supportedsigalgs - an optional property to list the JWS signing algorithms that the active TEE supports. When a TAM sends a signed message that the TEE isn't able to validate, it can include signature algorithms that it is able to consume in this status report. A TAM can generate a new request message to retry the management task with a TEE-supported signing algorithm. If the TEE isn't able to sign an error message due to an internal device error, a general error message should be returned by the OTrP Broker. 9.1.7. TAM Processing Requirements Upon receiving a GetDeviceStateResponse message at a TAM, the TAM MUST validate the following. o Parse to get list of GetDeviceTEEStateResponse JSON objects o Parse the JSON "payload" property and decrypt the JSON element "edsi". The decrypted message contains the TEE signer certificate. o Validate the GetDeviceTEEStateResponse JSON signature. The signer certificate is extracted from the decrypted message in the last step. o Extract TEE information and check it against its TEE acceptance policy. o Extract the TFW signed element, and check the signer and data integration against its TFW policy. o Check the SD list and TA list and prepare for a subsequent command such as "CreateSD" if it needs to have a new SD for an SP. Pei, et al. Expires April 26, 2019 [Page 39] Internet-Draft OTrP October 2018 9.2. Security Domain Management 9.2.1. CreateSD This command is typically preceded with a GetDeviceState command that has acquired the device information of the target device by the TAM. The TAM sends such a command to instruct a TEE to create a new Security Domain for an SP. A TAM sends an OTrP CreateSDRequest Request message to a device TEE to create a Security Domain for an SP. Such a request is signed by the TAM where the TAM signer may or may not be the same as the SP's TA signer certificate. The resulting SD is associated with two identifiers for future management: o TAM as the owner. The owner identifier is a registered unique TAM ID that is stored in the TAM certificate. o SP identified by its TA signer certificate as the authorization. A TAM can add more than one SP certificate to an SD. A Trusted Application that is signed by a matching SP signer certificate for an SD is eligible to be installed into that SD. The TA installation into an SD by a subsequent InstallTARequest message may be instructed from a TAM. 9.2.1.1. CreateSDRequest Message Pei, et al. Expires April 26, 2019 [Page 40] Internet-Draft OTrP October 2018 The request message for CreateSD has the following JSON format. { "CreateSDTBSRequest": { "ver": "1.0", "rid": "", "tid": "", // this may be from prior message "tee": "", "nextdsi": true | false, "dsihash": "", "content": ENCRYPTED { // this piece of JSON data will be // encrypted "spid": "", "sdname": "", "spcert": "", "tamid": "", "did": "" } } } In the message, rid - A unique value to identify this request tid - A unique value to identify this transaction. It can have the same value for the tid in the preceding GetDeviceStateRequest. tee - TEE ID returned from the previous GetDeviceStateResponse. nextdsi - Indicates whether the up-to-date Device State Information (DSI) is expected in the response from the TEE to this request. dsihash - The BASE64-encoded SHA256 hash value of the DSI data returned in the prior TAM operation with this target TEE. This value is always included such that a receiving TEE can check whether the device state has changed since its last query. It helps enforce SD update order in the right sequence without accidentally overwriting an update that was done simultaneously. content - The "content" is a JSON encrypted message that includes actual input for the SD creation. The encryption key is TAMmk that is encrypted by the target TEE's public key. The entire message is signed by the TAM private key TAMpriv. A separate TAMmk isn't used in the latest specification because JSON encryption will use a content encryption key for exactly the same purpose. Pei, et al. Expires April 26, 2019 [Page 41] Internet-Draft OTrP October 2018 spid - A unique id assigned by the TAM for its SP. It should be unique within a TAM namespace. sdname - a name unique to the SP. TAM should ensure it is unique for each SP. spcert - The SP's TA signer certificate is included in the request. This certificate will be stored by the device TEE which uses it to check against TA installation. Only if a TA is signed by a matching spcert associated with an SD will the TA be installed into the SD. tamid - SD owner claim by TAM - an SD owned by a TAM will be associated with a trusted identifier defined as an attribute in the signer TAM certificate. TEE will be responsible to assign this ID to the SD. The TAM certificate attribute for this attribute tamid MUST be vetted by the TAM signer issuing CA. With this trusted identifier, the SD query at TEE can be fast upon TAM signer verification. did - The SHA256 hash of the binary-encoded device TEE certificate. The encryption key CEK will be encrypted the recipient TEE's public key. This hash value in the "did" property allows the recipient TEE to check whether it is the expected target to receive such a request. If this isn't given, an OTrP message for device 2 could be sent to device 1. It is optional for the TEE to check because the successful decryption of the request message with this device's TEE private key already proves it is the target. This explicit hash value makes the protocol not dependent on message encryption method in future. A CreateSDTBSRequest message is signed to generate a final CreateSDRequest message as follows. { "CreateSDRequest": { "payload": "", "protected": "", "header": "", "signature": "" } } The TAM signer certificate is included in the "header" property. Pei, et al. Expires April 26, 2019 [Page 42] Internet-Draft OTrP October 2018 9.2.1.2. Request Processing Requirements at a TEE Upon receiving a CreateSDRequest request message at a TEE, the TEE MUST do the following: 1. Validate the JSON request message as follows * Validate JSON message signing. * Validate that the request TAM certificate is chained to a trusted CA that the TEE embeds as its trust anchor. * Compare dsihash with its current state to make sure nothing has changed since this request was sent. * Decrypt to get the plaintext of the content: (a) spid, (b) sd name, (c) did. * Check that an SPID is supplied. * spcert check: check it is a valid certificate (signature and format verification only). * Check "did" is the SHA256 hash of its TEEcert BER raw binary data. * Check whether the requested SD already exists for the SP. * Check that the tamid in the request matches the TAM certificate's TAM ID attribute. 2. If the request was valid, create action * Create an SD for the SP with the given name. * Assign the tamid from the TAMCert to this SD. * Assign the SPID and SPCert to this SD. * Check whether a TEE SP AIK key pair already exists for the given SP ID. * Create TEE SP AIK key pair if it doesn't exist for the given SP ID. * Generate new DSI data if the request asks for updated DSI. 3. Construct a CreateSDResponse message Pei, et al. Expires April 26, 2019 [Page 43] Internet-Draft OTrP October 2018 * Create raw content + Operation status + "did" or full signer certificate information, + TEE SP AIK public key if DSI isn't going to be included + Updated DSI data if requested * The response message is encrypted with the same JWE CEK of the request without recreating a new content encryption key. * The encrypted message is signed with TEEpriv. The signer information ("did" or TEEcert) is encrypted. 4. Deliver the response message. (a) The OTrP Broker returns this to the Client Application; (b) The Client App passes this back to the TAM. 5. TAM processing. (a) The TAM processes the response message; (b) the TAM can look up signer certificate from the device ID "did". If a request is illegitimate or signature doesn't pass, a "status" property in the response will indicate the error code and cause. 9.2.1.3. CreateSDResponse Message The response message for a CreateSDRequest contains the following content. { "CreateSDTBSResponse": { "ver": "1.0", "status": "", "rid": "", "tid": "", "content": ENCRYPTED { "reason": "", // optional "did": "", "sdname": "", "teespaik": "", "dsi": "" } } } Pei, et al. Expires April 26, 2019 [Page 44] Internet-Draft OTrP October 2018 In the response message, the following fields MUST be supplied. did - The SHA256 hash of the device TEE certificate. This shows the device ID explicitly to the receiving TAM. teespaik - The newly generated SP AIK public key for the given SP. This is an optional value if the device has had another domain for the SP that has triggered TEE SP AIK key pair for this specific SP. There is a possible extreme error case where the TEE isn't reachable or the TEE final response generation itself fails. In this case, the TAM might still receive a response from the OTrP Broker if the OTrP Broker is able to detect such error from TEE. In this case, a general error response message should be returned by the OTrP Broker, assuming OTrP Broker even doesn't know any content and information about the request message. In other words, the TAM should expect to receive a TEE successfully signed JSON message, a general "status" message, or none when a client experiences a network error. { "CreateSDResponse": { "payload": "", "protected": { "" }, "signature": "" } } A response message type "status" will be returned when the TEE fails to respond. The OTrP Broker is responsible to create this message. { "status": { "result": "fail", "error-code": "ERR_AGENT_TEE_FAIL", "error-message": "TEE fails to respond" } } Pei, et al. Expires April 26, 2019 [Page 45] Internet-Draft OTrP October 2018 9.2.1.4. Error Conditions An error might occur if a request isn't valid or the TEE runs into some error. The list of possible errors are as follows. Refer to the Error Code List (Section 13.1) for detailed causes and actions. ERR_AGENT_TEE_BUSY ERR_AGENT_TEE_FAIL ERR_AGENT_TEE_UNKNOWN ERR_REQUEST_INVALID ERR_UNSUPPORTED_MSG_VERSION ERR_UNSUPPORTED_CRYPTO_ALG ERR_DEV_STATE_MISMATCH ERR_SD_ALREADY_EXIST ERR_SD_NOT_FOUND ERR_SPCERT_INVALID ERR_TEE_FAIL ERR_TAM_NOT_AUTHORIZED ERR_TAM_NOT_TRUSTED 9.2.2. UpdateSD This TAM initiated command can update an SP's SD that it manages for any of the following needs: (a) Update an SP signer certificate; (b) Add an SP signer certificate when an SP uses multiple to sign TA binaries; (c) Update an SP ID. The TAM presents the proof of the SD ownership to the TEE, and includes related information in its signed message. The entire request is also encrypted for end-to-end confidentiality. 9.2.2.1. UpdateSDRequest Message Pei, et al. Expires April 26, 2019 [Page 46] Internet-Draft OTrP October 2018 The UpdateSD request message has the following JSON format. { "UpdateSDTBSRequest": { "ver": "1.0", "rid": "", "tid": "", // this may be from prior message "tee": "", "nextdsi": true | false, "dsihash": "", "content": ENCRYPTED { // this piece of JSON will be encrypted "tamid": "", "spid": "", "sdname": "", "changes": { "newsdname": "", // Optional "newspid": "", // Optional "spcert": [""], // Optional "deloldspcert": [""], // Optional "renewteespaik": true | false } } } } In the message, rid - A unique value to identify this request tid - A unique value to identify this transaction. It can have the same value as the tid in the preceding GetDeviceStateRequest. tee - TEE ID returned from the previous GetDeviceStateResponse nextdsi - Indicates whether the up-to-date Device State Information (DSI) is expected to be returned in the response from the TEE to this request. dsihash - The BASE64-encoded SHA256 hash value of the DSI data returned in the prior TAM operation with this target TEE. This value is always included such that a receiving TEE can check whether the device state has changed since its last query. It Pei, et al. Expires April 26, 2019 [Page 47] Internet-Draft OTrP October 2018 helps enforce SD update order in the right sequence without accidentally overwriting an update that was done simultaneously. content - The "content" is a JSON encrypted message that includes actual input for the SD update. The standard JSON content encryption key (CEK) is used, and the CEK is encrypted by the target TEE's public key. tamid - SD owner claim by TAM - an SD owned by a TAM will be associated with a trusted identifier defined as an attribute in the signer TAM certificate. spid - the identifier of the SP whose SD will be updated. This value is still needed because the SD name is considered unique only within an SP. sdname - the name of the target SD to be updated. changes - its content consists of changes are to be updated in the given SD. newsdname - the new name of the target SD to be assigned if this value is present. newspid - the new SP ID of the target SD to be assigned if this value is present. spcert - a new TA signer certificate of this SP to be added to the SD if this is present. deloldspcert - an SP certificate assigned into the SD is to be deleted if this is present. The value is the SHA256 fingerprint of the old SP certificate. renewteespaik - the value should be true or false. If it is present and the value is true, the TEE MUST regenerate TEE SP AIK for this SD's owner SP. The newly generated TEE SP AIK for the SP must be returned in the response message of this request. If there is more than one SD for the SP, a new SPID for one of the domains will always trigger a new teespaik generation as if a new SP were introduced to the TEE. Pei, et al. Expires April 26, 2019 [Page 48] Internet-Draft OTrP October 2018 The UpdateSDTBSRequest message is signed to generate the final UpdateSDRequest message. { "UpdateSDRequest": { "payload": "", "protected": "", "header": "", "signature":"" } } TAM signer certificate is included in the "header" property. 9.2.2.2. Request Processing Requirements at a TEE Upon receiving a request message UpdateSDRequest at a TEE, the TEE must validate a request: 1. Validate the JSON request message * Validate JSON message signing * Validate that the request TAM certificate is chained to a trusted CA that the TEE embeds as its trust anchor.The TAM certificate status check is generally not needed anymore in this request. The prior request should have validated the TAM certificate's revocation status. * Compare dsihash with the TEE cached last response DSI data to this TAM. * Decrypt to get the plaintext of the content. * Check that the target SD name is supplied. * Check whether the requested SD exists. * Check that the TAM owns this TAM by verifying tamid in the SD matches TAM certificate's TAM ID attribute. * Now the TEE is ready to carry out update listed in the "content" message. 2. If the request is valid, update action * If "newsdname" is given, replace the SD name for the SD to the new value Pei, et al. Expires April 26, 2019 [Page 49] Internet-Draft OTrP October 2018 * If "newspid" is given, replace the SP ID assigned to this SD with the given new value * If "spcert" is given, add this new SP certificate to the SD. * If "deloldspcert" is present in the content, check previously assigned SP certificates to this SD, and delete the one that matches the given certificate hash value. * If "renewteespaik" is given and has a value of 'true', generate a new TEE SP AIK key pair, and replace the old one with this. * Generate new DSI data if the request asks for updated DSI * Now the TEE is ready to construct the response message 3. Construct UpdateSDResponse message * Create raw content + Operation status + "did" or full signer certificate information, + TEE SP AIK public key if DSI isn't going to be included + Updated DSI data if requested * The response message is encrypted with the same JWE CEK of the request without recreating a new content encryption key. * The encrypted message is signed with TEEpriv. The signer information ("did" or TEEcert) is encrypted. 4. Deliver response message. (a) The OTrP Broker returns this to the app; (b) The app passes this back to the TAM. 5. TAM processing. (a) The TAM processes the response message; (b) The TAM can look up the signer certificate from the device ID "did". If a request is illegitimate or the signature doesn't pass, a "status" property in the response will indicate the error code and cause. Pei, et al. Expires April 26, 2019 [Page 50] Internet-Draft OTrP October 2018 9.2.2.3. UpdateSDResponse Message The response message for a UpdateSDRequest contains the following content. { "UpdateSDTBSResponse": { "ver": "1.0", "status": "", "rid": "", "tid": "", "content": ENCRYPTED { "reason": "", // optional "did": "", "cert": "", // optional "teespaik": "", "teespaiktype": "", "dsi": "" } } } In the response message, the following fields MUST be supplied. did - The request should have known the signer certificate of this device from a prior request. This hash value of the device TEE certificate serves as a quick identifier only. A full device certificate isn't necessary. teespaik - the newly generated SP AIK public key for the given SP if the TEE SP AIK for the SP is asked to be renewed in the request. This is an optional value if "dsi" is included in the response, which will contain all up-to-date TEE SP AIK key pairs. Similar to the template for the creation of the encrypted and signed CreateSDResponse, the final UpdateSDResponse looks like the following. Pei, et al. Expires April 26, 2019 [Page 51] Internet-Draft OTrP October 2018 { "UpdateSDResponse": { "payload": "", "protected": { "" }, "signature": "" } } A response message type "status" will be returned when the TEE fails to respond. The OTrP Broker is responsible to create this message. { "status": { "result": "fail", "error-code": "ERR_AGENT_TEE_FAIL", "error-message": "" } } 9.2.2.4. Error Conditions An error may occur if a request isn't valid or the TEE runs into some error. The list of possible errors are as follows. Refer to the Error Code List (Section 13.1) for detailed causes and actions. ERR_AGENT_TEE_BUSY ERR_AGENT_TEE_FAIL ERR_AGENT_TEE_UNKNOWN ERR_REQUEST_INVALID ERR_UNSUPPORTED_MSG_VERSION ERR_UNSUPPORTED_CRYPTO_ALG ERR_DEV_STATE_MISMATCH ERR_SD_NOT_FOUND ERR_SDNAME_ALREADY_USED ERR_SPCERT_INVALID Pei, et al. Expires April 26, 2019 [Page 52] Internet-Draft OTrP October 2018 ERR_TEE_FAIL ERR_TAM_NOT_AUTHORIZED ERR_TAM_NOT_TRUSTED 9.2.3. DeleteSD A TAM sends a DeleteSDRequest message to a TEE to delete a specified SD that it owns. An SD can be deleted only if there is no TA associated with this SD in the device. The request message can contain a flag to instruct the TEE to delete all related TAs in an SD and then delete the SD. The target TEE will operate with the following logic. 1. Look up the given SD specified in the request message 2. Check that the TAM owns the SD 3. Check that the device state hasn't changed since the last operation 4. Check whether there are TAs in this SD 5. If TA exists in an SD, check whether the request instructs whether the TA should be deleted. If the request instructs the TEE to delete TAs, delete all TAs in this SD. If the request doesn't instruct the TEE to delete TAs, return an error "ERR_SD_NOT_EMPTY". 6. Delete the SD 7. If this is the last SD of this SP, delete the TEE SP AIK key. 9.2.3.1. DeleteSDRequest Message Pei, et al. Expires April 26, 2019 [Page 53] Internet-Draft OTrP October 2018 The request message for DeleteSD has the following JSON format. { "DeleteSDTBSRequest": { "ver": "1.0", "rid": "", "tid": "", // this may be from prior message "tee": "", "nextdsi": true | false, "dsihash": "", "content": ENCRYPTED { // this piece of JSON will be encrypted "tamid": "", "sdname": "", "deleteta": true | false } } } In the message, rid - A unique value to identify this request tid - A unique value to identify this transaction. It can have the same value for the tid in the preceding GetDeviceStateRequest. tee - TEE ID returned from the previous response GetDeviceStateResponse nextdsi - Indicates whether the up-to-date Device State Information (DSI) is to be returned in the response to this request. dsihash - The BASE64-encoded SHA256 hash value of the DSI data returned in the prior TAM operation with this target TEE. This value is always included such that a receiving TEE can check whether the device state has changed since its last query. It helps enforce SD update order in the right sequence without accidentally overwriting an update that was done simultaneously. content - The "content" is a JSON encrypted message that includes actual input for the SD update. The standard JSON content encryption key (CEK) is used, and the CEK is encrypted by the target TEE's public key. tamid - SD owner claim by TAM - an SD owned by a TAM will be associated with a trusted identifier defined as an attribute in the signer TAM certificate. sdname - the name of the target SD to be updated. Pei, et al. Expires April 26, 2019 [Page 54] Internet-Draft OTrP October 2018 deleteta - the value should be boolean 'true' or 'false'. If it is present and the value is 'true', the TEE should delete all TAs associated with the SD in the device. According to the OTrP message template, the full request DeleteSDRequest is a signed message over the DeleteSDTBSRequest as follows. { "DeleteSDRequest": { "payload": "", "protected": "", "header": "", "signature": "" } } TAM signer certificate is included in the "header" property. 9.2.3.2. Request Processing Requirements at a TEE Upon receiving a request message DeleteSDRequest at a TEE, the TEE must validate a request: 1. Validate the JSON request message * Validate JSON message signing * Validate that the request TAM certificate is chained to a trusted CA that the TEE embeds as its trust anchor. The TAM certificate status check is generally not needed anymore in this request. The prior request should have validated the TAM certificate's revocation status. * Compare dsihash with the TEE cached last response DSI data to this TAM * Decrypt to get the plaintext of the content * Check that the target SD name is supplied * Check whether the requested SD exists * Check that the TAM owns this TAM by verifying that the tamid in the SD matches the TAM certificate's TAM ID attribute * Now the TEE is ready to carry out the update listed in the "content" message Pei, et al. Expires April 26, 2019 [Page 55] Internet-Draft OTrP October 2018 2. If the request is valid, deletion action * Check TA existence in this SD * If "deleteta" is "true", delete all TAs in this SD. If the value of "deleteta" is false and some TA exists, return an error "ERR_SD_NOT_EMPTY" * Delete the SD * Delete the TEE SP AIK key pair if this SD is the last one for the SP * Now the TEE is ready to construct the response message 3. Construct a DeleteSDResponse message * Create response content + Operation status + "did" or full signer certificate information, + Updated DSI data if requested * The response message is encrypted with the same JWE CEK of the request without recreating a new content encryption key. * The encrypted message is signed with TEEpriv. The signer information ("did" or TEEcert) is encrypted. 4. Deliver response message. (a) The OTrP Broker returns this to the app; (b) The app passes this back to the TAM 5. TAM processing. (a) The TAM processes the response message; (b) The TAM can look up signer certificate from the device ID "did". If a request is illegitimate or the signature doesn't pass, a "status" property in the response will indicate the error code and cause. 9.2.3.3. DeleteSDResponse Message The response message for a DeleteSDRequest contains the following content. Pei, et al. Expires April 26, 2019 [Page 56] Internet-Draft OTrP October 2018 { "DeleteSDTBSResponse": { "ver": "1.0", "status": "", "rid": "", "tid": "", "content": ENCRYPTED { "reason": "", // optional "did": "", "dsi": "" } } } In the response message, the following fields MUST be supplied. did - The request should have known the signer certificate of this device from a prior request. This hash value of the device TEE certificate serves as a quick identifier only. A full device certificate isn't necessary. The final DeleteSDResponse looks like the following. { "DeleteSDResponse": { "payload": "", "protected": { "" }, "signature": "" } } A response message type "status" will be returned when the TEE fails to respond. The OTrP Broker is responsible to create this message. { "status": { "result": "fail", "error-code": "ERR_AGENT_TEE_FAIL", "error-message": "TEE fails to respond" } } Pei, et al. Expires April 26, 2019 [Page 57] Internet-Draft OTrP October 2018 9.2.3.4. Error Conditions An error may occur if a request isn't valid or the TEE runs into some error. The list of possible errors is as follows. Refer to the Error Code List (Section 13.1) for detailed causes and actions. ERR_AGENT_TEE_BUSY ERR_AGENT_TEE_FAIL ERR_AGENT_TEE_UNKNOWN ERR_REQUEST_INVALID ERR_UNSUPPORTED_MSG_VERSION ERR_UNSUPPORTED_CRYPTO_ALG ERR_DEV_STATE_MISMATCH ERR_SD_NOT_EMPTY ERR_SD_NOT_FOUND ERR_TEE_FAIL ERR_TAM_NOT_AUTHORIZED ERR_TAM_NOT_TRUSTED 9.3. Trusted Application Management This protocol doesn't introduce a TA container concept. All TA authorization and management will be up to the TEE implementation. The following three TA management commands are supported. o InstallTA - provision a TA by TAM o UpdateTA - update a TA by TAM o DeleteTA - remove TA registration information with an SD, remove the TA binary and all TA-related data in a TEE Pei, et al. Expires April 26, 2019 [Page 58] Internet-Draft OTrP October 2018 9.3.1. InstallTA TA binary data and related personalization data if there is any can be from two sources: 1. A TAM supplies the signed and encrypted TA binary 2. A Client Application supplies the TA binary This specification primarily considers the first case where a TAM supplies a TA binary. This is to ensure that a TEE can properly validate whether a TA is trustworthy. Further, TA personalization data will be encrypted by the TEE device's SP public key for end-to- end protection. A Client Application bundled TA case will be addressed separately later. A TAM sends the following information in a InstallTARequest message to a target TEE: o The target SD information: SP ID and SD name o Encrypted TA binary data. TA data is encrypted with the TEE SP AIK. o TA metadata. It is optional to include the SP signer certificate for the SD to add if the SP has changed signer since the SD was created. The TEE processes the command given by the TAM to install a TA into an SP's SD. It does the following: o Validation * The TEE validates the TAM message authenticity * Decrypt to get request content * Look up the SD with the SD name * Checks that the TAM owns the SD * Checks that the DSI hash matches which shows that the device state hasn't changed o If the request is valid, continue to do the TA validation * Decrypt to get the TA binary data and any personalization data with the "TEE SP AIK private key" Pei, et al. Expires April 26, 2019 [Page 59] Internet-Draft OTrP October 2018 * Check that SP ID is the one that is registered with the SP SD * Check that the TA signer is either a newly given SP certificate or the one that is already trusted by the SD from the previous TA installation. The TA signing method is specific to a TEE. This specification doesn't define how a TA should be signed; a TAM should support TEE specific TA signing when it supports that TEE. * If a TA signer is given in the request, add this signer into the SD. o If the above validation passed, continue to do TA installation * The TEE re-encrypts the TA binary and its personalization data with its own method. * The TEE enrolls and stores the TA in a secure storage. o Construct a response message. This involves signing encrypted status information for the requesting TAM. 9.3.1.1. InstallTARequest Message Pei, et al. Expires April 26, 2019 [Page 60] Internet-Draft OTrP October 2018 The request message for InstallTA has the following JSON format. { "InstallTATBSRequest": { "ver": "1.0", "rid": "", "tid": "", "tee": "", "nextdsi": true | false, "dsihash": "", "content": ENCRYPTED { "tamid": "", "spid": "", "sdname": "", "spcert": "", // optional "taid": "" }, "encrypted_ta": { "key": "", "iv": "", "alg": "", "cipherpdata": "" } } } In the message, rid - A unique value to identify this request tid - A unique value to identify this transaction. It can have the same value for the tid in the preceding GetDeviceStateRequest. tee - TEE ID returned from the previous GetDeviceStateResponse nextdsi - Indicates whether the up-to-date Device State Information (DSI) is to be returned in the response to this request. dsihash - The BASE64-encoded SHA256 hash value of the DSI data returned in the prior TAM operation with this target TEE. This value is always included such that a receiving TEE can check whether the device state has changed since its last query. It helps enforce SD update order in the right sequence without accidentally overwriting an update that was done simultaneously. Pei, et al. Expires April 26, 2019 [Page 61] Internet-Draft OTrP October 2018 content - The "content" is a JSON encrypted message that includes actual input for the SD update. The standard JSON content encryption key (CEK) is used, and the CEK is encrypted by the target TEE's public key. tamid - SD owner claim by TAM - An SD owned by a TAM will be associated with a trusted identifier defined as an attribute in the signer TAM certificate. spid - SP identifier of the TA owner SP sdname - the name of the target SD where the TA is to be installed spcert - an optional field to specify the SP certificate that signed the TA. This is sent if the SP has a new certificate that hasn't been previously registered with the target SD where the TA should be installed. taid - the identifier of the TA application to be installed encrypted_ta - the message portion contains encrypted TA binary data and personalization data. The TA data encryption key is placed in "key", which is encrypted by the recipient's public key, using JWE enveloped structure. The TA data encryption uses symmetric key based encryption such as AESCBC. According to the OTrP message template, the full request InstallTARequest is a signed message over the InstallTATBSRequest as follows. { "InstallTARequest": { "payload": "", "protected": "", "header": "", "signature": "" } } 9.3.1.2. InstallTAResponse Message The response message for a InstallTARequest contains the following content. Pei, et al. Expires April 26, 2019 [Page 62] Internet-Draft OTrP October 2018 { "InstallTATBSResponse": { "ver": "1.0", "status": "", "rid": "", "tid": "", "content": ENCRYPTED { "reason":"", // optional "did": "", "dsi": "" } } } In the response message, the following fields MUST be supplied. did - the SHA256 hash of the device TEE certificate. This shows the device ID explicitly to the receiving TAM. The final message InstallTAResponse looks like the following. { "InstallTAResponse": { "payload":"", "protected": { "" }, "signature": "" } } A response message type "status" will be returned when the TEE fails to respond. The OTrP Broker is responsible to create this message. { "status": { "result": "fail", "error-code": "ERR_AGENT_TEE_FAIL", "error-message": "TEE fails to respond" } } Pei, et al. Expires April 26, 2019 [Page 63] Internet-Draft OTrP October 2018 9.3.1.3. Error Conditions An error may occur if a request isn't valid or the TEE runs into some error. The list of possible errors are as follows. Refer to the Error Code List (Section 13.1) for detailed causes and actions. ERR_AGENT_TEE_BUSY ERR_AGENT_TEE_FAIL ERR_AGENT_TEE_UNKNOWN ERR_REQUEST_INVALID ERR_UNSUPPORTED_MSG_VERSION ERR_UNSUPPORTED_CRYPTO_ALG ERR_DEV_STATE_MISMATCH ERR_SD_NOT_FOUND ERR_TA_INVALID ERR_TA_ALREADY_INSTALLED ERR_TEE_FAIL ERR_TEE_RESOURCE_FULL ERR_TAM_NOT_AUTHORIZED ERR_TAM_NOT_TRUSTED 9.3.2. UpdateTA This TAM-initiated command can update a TA and its data in an SP's SD that it manages for the following purposes. 1. Update TA binary 2. Update TA's personalization data The TAM presents the proof of the SD ownership to a TEE, and includes related information in its signed message. The entire request is also encrypted for end-to-end confidentiality. Pei, et al. Expires April 26, 2019 [Page 64] Internet-Draft OTrP October 2018 The TEE processes the command from the TAM to update the TA of an SP SD. It does the following: o Validation * The TEE validates the TAM message authenticity * Decrypt to get request content * Look up the SD with the SD name * Checks that the TAM owns the SD * Checks DSI hash matches that the device state hasn't changed o TA validation * Both TA binary and personalization data are optional, but at least one of them shall be present in the message * Decrypt to get the TA binary and any personalization data with the "TEE SP AIK private key" * Check that SP ID is the one that is registered with the SP SD * Check that the TA signer is either a newly given SP certificate or the one in SD. * If a TA signer is given in the request, add this signer into the SD. o If the above validation passes, continue to do TA update * The TEE re-encrypts the TA binary and its personalization data with its own method * The TEE replaces the existing TA binary and its personalization data with the new binary and data. o Construct a response message. This involves signing a encrypted status information for the requesting TAM. 9.3.2.1. UpdateTARequest Message Pei, et al. Expires April 26, 2019 [Page 65] Internet-Draft OTrP October 2018 The request message for UpdateTA has the following JSON format. { "UpdateTATBSRequest": { "ver": "1.0", "rid": "", "tid": "", "tee": "", "nextdsi": true | false, "dsihash": "", "content": ENCRYPTED { "tamid": "", "spid": "", "sdname": "", "spcert": "", // optional "taid": "" }, "encrypted_ta": { "key": "", "iv": "", "alg": "", "ciphernewpdata": "" // optional } } } In the message, rid - A unique value to identify this request tid - A unique value to identify this transaction. It can have the same value for the tid in the preceding GetDeviceStateRequest. tee - TEE ID returned from the previous GetDeviceStateResponse nextdsi - Indicates whether the up-to-date Device State Information (DSI) is to be returned in the response to this request. dsihash - The BASE64-encoded SHA256 hash value of the DSI data returned in the prior TAM operation with this target TEE. This value is always included such that a receiving TEE can check whether the device state has changed since its last query. It Pei, et al. Expires April 26, 2019 [Page 66] Internet-Draft OTrP October 2018 helps enforce SD update order in the right sequence without accidentally overwriting an update that was done simultaneously. content - The "content" is a JSON encrypted message that includes actual input for the SD update. The standard JSON content encryption key (CEK) is used, and the CEK is encrypted by the target TEE's public key. tamid - SD owner claim by TAM - an SD owned by a TAM will be associated with a trusted identifier defined as an attribute in the signer TAM certificate. spid - SP identifier of the TA owner SP spcert - an optional field to specify the SP certificate that signed the TA. This is sent if the SP has a new certificate that hasn't been previously registered with the target SD where the TA is to be installed. sdname - the name of the target SD where the TA should be updated taid - an identifier for the TA application to be updated encrypted_ta - the message portion contains newly encrypted TA binary data and personalization data. According to the OTrP message template, the full request UpdateTARequest is a signed message over the UpdateTATBSRequest as follows. { "UpdateTARequest": { "payload": "", "protected": "", "header": "", "signature": "" } } 9.3.2.2. UpdateTAResponse Message The response message for a UpdateTARequest contains the following content. Pei, et al. Expires April 26, 2019 [Page 67] Internet-Draft OTrP October 2018 { "UpdateTATBSResponse": { "ver": "1.0", "status": "", "rid": "", "tid": "", "content": ENCRYPTED { "reason": "", // optional "did": "", "dsi": "" } } } In the response message, the following fields MUST be supplied. did - the SHA256 hash of the device TEE certificate. This shows the device ID explicitly to the receiving TAM. The final message UpdateTAResponse looks like the following. { "UpdateTAResponse": { "payload":"", "protected": { "" }, "signature": "" } } A response message type "status" will be returned when the TEE fails to respond. The OTrP Broker is responsible to create this message. { "status": { "result": "fail", "error-code": "ERR_AGENT_TEE_FAIL", "error-message": "TEE fails to respond" } } Pei, et al. Expires April 26, 2019 [Page 68] Internet-Draft OTrP October 2018 9.3.2.3. Error Conditions An error may occur if a request isn't valid or the TEE runs into some error. The list of possible errors are as follows. Refer to the Error Code List (Section 13.1) for detailed causes and actions. ERR_AGENT_TEE_BUSY ERR_AGENT_TEE_FAIL ERR_AGENT_TEE_UNKNOWN ERR_REQUEST_INVALID ERR_UNSUPPORTED_MSG_VERSION ERR_UNSUPPORTED_CRYPTO_ALG ERR_DEV_STATE_MISMATCH ERR_SD_NOT_FOUND ERR_TA_INVALID ERR_TA_NOT_FOUND ERR_TEE_FAIL ERR_TAM_NOT_AUTHORIZED ERR_TAM_NOT_TRUSTED 9.3.3. DeleteTA This operation defines OTrP messages that allow a TAM to instruct a TEE to delete a TA for an SP in a given SD. A TEE will delete a TA from an SD and also TA data in the TEE. A Client Application cannot directly access TEE or OTrP Broker to delete a TA. 9.3.3.1. DeleteTARequest Message Pei, et al. Expires April 26, 2019 [Page 69] Internet-Draft OTrP October 2018 The request message for DeleteTA has the following JSON format. { "DeleteTATBSRequest": { "ver": "1.0", "rid": "", "tid": "", "tee": "", "nextdsi": true | false, "dsihash": "", "content": ENCRYPTED { "tamid": "", "sdname": "", "taid": "" } } } In the message, rid - A unique value to identify this request tid - A unique value to identify this transaction. It can have the same value for the tid in the preceding GetDeviceStateRequest. tee - The TEE ID returned from the previous GetDeviceStateResponse nextdsi - Indicates whether the up-to-date Device State Information (DSI) is to be returned in the response to this request. dsihash - The BASE64-encoded SHA256 hash value of the DSI data returned in the prior TAM operation with this target TEE. This value is always included such that a receiving TEE can check whether the device state has changed since its last query. It helps enforce SD update order in the right sequence without accidentally overwriting an update that was done simultaneously. content - The "content" is a JSON encrypted message that includes actual input for the SD update. The standard JSON content encryption key (CEK) is used, and the CEK is encrypted by the target TEE's public key. tamid - SD owner claim by TAM - an SD owned by a TAM will be associated with a trusted identifier defined as an attribute in the signer TAM certificate. sdname - the name of the target SD where the TA is installed Pei, et al. Expires April 26, 2019 [Page 70] Internet-Draft OTrP October 2018 taid - an identifier for the TA application to be deleted According to the OTrP message template, the full request DeleteTARequest is a signed message over the DeleteTATBSRequest as follows. { "DeleteTARequest": { "payload": "", "protected": "", "header": "", "signature": "" } } 9.3.3.2. Request Processing Requirements at a TEE A TEE processes a command from a TAM to delete a TA of an SP SD. It does the following: 1. Validate the JSON request message * The TEE validates TAM message authenticity * Decrypt to get request content * Look up the SD and the TA with the given SD name and TA ID * Checks that the TAM owns the SD, and TA is installed in the SD * Checks that the DSI hash matches and the the device state hasn't changed 2. Deletion action * If all the above validation points pass, the TEE deletes the TA from the SD * The TEE SHOULD also delete all personalization data for the TA 3. Construct DeleteTAResponse message. If a request is illegitimate or the signature doesn't pass, a "status" property in the response will indicate the error code and cause. Pei, et al. Expires April 26, 2019 [Page 71] Internet-Draft OTrP October 2018 9.3.3.3. DeleteTAResponse Message The response message for a DeleteTARequest contains the following content. { "DeleteTATBSResponse": { "ver": "1.0", "status": "", "rid": "", "tid": "", "content": ENCRYPTED { "reason": "", // optional "did": "", "dsi": "" } } } In the response message, the following fields MUST be supplied. did - the SHA256 hash of the device TEE certificate. This shows the device ID explicitly to the receiving TAM. The final message DeleteTAResponse looks like the following. { "DeleteTAResponse": { "payload": "", "protected": { "" }, "signature": "" } } A response message type "status" will be returned when the TEE fails to respond. The OTrP Broker is responsible to create this message. Pei, et al. Expires April 26, 2019 [Page 72] Internet-Draft OTrP October 2018 { "status": { "result": "fail", "error-code": "ERR_AGENT_TEE_FAIL", "error-message": "TEE fails to respond" } } 9.3.3.4. Error Conditions An error may occur if a request isn't valid or the TEE runs into some error. The list of possible errors are as follows. Refer to the Error Code List (Section 13.1) for detailed causes and actions. ERR_AGENT_TEE_BUSY ERR_AGENT_TEE_FAIL ERR_AGENT_TEE_UNKNOWN ERR_REQUEST_INVALID ERR_UNSUPPORTED_MSG_VERSION ERR_UNSUPPORTED_CRYPTO_ALG ERR_DEV_STATE_MISMATCH ERR_SD_NOT_FOUND ERR_TA_NOT_FOUND ERR_TEE_FAIL ERR_TAM_NOT_AUTHORIZED ERR_TAM_NOT_TRUSTED 10. Response Messages a TAM May Expect A TAM expects some feedback from a remote device when a request message is delivered to a device. The following three types of responses SHOULD be supplied. Type 1: Expect a valid TEE-generated response message A valid TEE signed response may contain errors detected by a TEE, e.g. a TAM is trusted but some TAM-supplied data is missing, for Pei, et al. Expires April 26, 2019 [Page 73] Internet-Draft OTrP October 2018 example, SP ID doesn't exist. TEE MUST be able to sign and encrypt. If a TEE isn't able to sign a response, the TEE returns an error to the OTrP Broker without giving any other internal information. The OTrP Broker will be generating the response. Type 2: The OTrP Broker generated error message when TEE fails. OTrP Broker errors will be defined in this document. A Type 2 message has the following format. { "OTrPBrokerError": { "ver": "1.0", "rid": "", "tid": "", "errcode": "ERR_AGENT_TEE_UNKNOWN | ERR_AGENT_TEE_BUSY" } } Type 3: OTrP Broker itself isn't reachable or fails. A Client Application is responsible to handle error and respond the TAM in its own way. This is out of scope for this specification. 11. Basic Protocol Profile This section describes a baseline for interoperability among the protocol entities, mainly, the TAM and TEE. A TEE MUST support RSA algorithms. It is optional to support ECC algorithms. A TAM SHOULD use a RSA certificate for TAM message signing. It may use an ECC certificate if it detects that the TEE supports ECC according to the field "supportedsigalgs" in a TEE response. A TAM MUST support both RSA 2048-bit algorithm and ECC P-256 algorithms. With this, a TEE and TFW certificate can be either RSA or ECC type. JSON signing algorithms o RSA PKCS#1 with SHA256 signing : "RS256" o ECDSA with SHA256 signing : "ES256" JSON asymmetric encryption algorithms (describes key-exchange or key- agreement algorithm for sharing symmetric key with TEE): Pei, et al. Expires April 26, 2019 [Page 74] Internet-Draft OTrP October 2018 o RSA PKCS#1 : "RSA1_5" o ECDH using TEE ECC P-256 key and ephemeral ECC key generated by TAM : "ECDH-ES+A128W" JSON symmetric encryption algorithms (describes symmetric algorithm for encrypting body of data, using symmetric key transferred to TEE using asymmetric encryption): o Authenticated encryption AES 128 CBC with SHA256 : {"enc":"A128CBC-HS256"} 12. Attestation Implementation Consideration It is important to know that the state of a device is appropriate before trusting that a device is what it says it is. The attestation scheme for OTrP must also be able to cope with different TEEs, including those that are OTrP compliant and those that use another mechanism. In the initial version, only one active TEE is assumed. It is out of scope how the TAM and the device implement the trust hierarchy verification. However, it is helpful to understand what each system provider should do in order to properly implement an OTrP trust hierarchy. In this section, we provide some implementation reference consideration. 12.1. OTrP Trusted Firmware 12.1.1. Attestation signer It is proposed that attestation for OTrP is based on the TFW layer, and that further attestation is not performed within the TEE itself during Security Domain operations. The rationale is that the device boot process will be defined to start with a secure bootloader protected with a harden key in eFUSE. The process releases attestation signing capabilities into the TFW once a trust boot has been established. In this way the release of the attestation signer can be considered the first "platform configuration metric", using Trust Computing Group (TCG) terminology. 12.1.2. TFW Initial Requirements R1 The TFW must be possible for verification during boot R2 The TFW must allow a public / private key pair to be generated during device manufacture Pei, et al. Expires April 26, 2019 [Page 75] Internet-Draft OTrP October 2018 R3 The public key and certificate must be possible to store securely R4 The private key must be possible to store encrypted at rest R5 The private key must only be visible to the TFW when it is decrypted R6 The TFW must be able to read a list of root and intermediate certificates that it can use to check certificate chains with. The list must be stored such that it cannot be tampered with R7 Need to allow a TEE to access its unique TEE specific private key 12.2. TEE Loading During boot, the TFW is required to start all of the root TEEs. Before loading them, the TFW must first determine whether the code sign signature of the TEE is valid. If TEE integrity is confirmed, the TEE may be started. The TFW must then be able to receive the identity certificate from the TEE (if that TEE is OTrP compliant). The identity certificate and keys will need to be baked into the TEE image, and therefore also covered by the code signer hash during the manufacturing process. The private key for the identity certificate must be securely protected. The private key for a TEE identity must never be released no matter how the public key and certificate are released to the TFW. Once the TFW has successfully booted a TEE and retrieved the identity certificate, the TFW will commit this to the platform configuration register (PCR) set, for later use during attestation. At minimum, the following data must be committed to the PCR for each TEE: 1. Public key and certificate for the TEE 2. TEE identifier that can be used later by a TAM to identify this TEE 12.3. Attestation Hierarchy The attestation hierarchy and seed required for TAM protocol operation must be built into the device at manufacture. Additional TEEs can be added post-manufacture using the scheme proposed, but it is outside of the current scope of this document to detail that. It should be noted that the attestation scheme described is based on signatures. The only decryption that may take place is through the use of a bootloader key. Pei, et al. Expires April 26, 2019 [Page 76] Internet-Draft OTrP October 2018 12.3.1. Attestation Hierarchy Establishment: Manufacture During manufacture the following steps are required: 1. A device-specific TFW key pair and certificate are burnt into the device. This key pair will be used for signing operations performed by the TFW. 2. TEE images are loaded and include a TEE instance-specific key pair and certificate. The key pair and certificate are included in the image and covered by the code signing hash. 3. The process for TEE images is repeated for any subordinate TEEs, which are additional TEEs after the root TEE that some devices have. 12.3.2. Attestation Hierarchy Establishment: Device Boot During device boot the following steps are required: 1. The boot module releases the TFW private key by decrypting it with the bootloader key. 2. The TFW verifies the code-signing signature of the active TEE and places its TEE public key into a signing buffer, along with its identifier for later access. For a non-OTrP TEE, the TFW leaves the TEE public key field blank. 3. The TFW signs the signing buffer with the TFW private key. 4. Each active TEE performs the same operation as the TFW, building up their own signed buffer containing subordinate TEE information. 12.3.3. Attestation Hierarchy Establishment: TAM Before a TAM can begin operation in the marketplace to support devices of a given TEE, it must obtain a TAM certificate from a CA that is registered in the trust store of devices with that TEE. In this way, the TEE can check the intermediate and root CA and verify that it trusts this TAM to perform operations on the TEE. 13. IANA Considerations The error code listed in the next section will be registered. Pei, et al. Expires April 26, 2019 [Page 77] Internet-Draft OTrP October 2018 13.1. Error Code List This section lists error codes that could be reported by a TA or TEE in a device in responding to a TAM request, and a separate list that OTrP Broker may return when the TEE fails to respond. 13.1.1. TEE Signed Error Code List ERR_DEV_STATE_MISMATCH - A TEE will return this error code if the DSI hash value from TAM doesn't match the has value of the device's current DSI. ERR_SD_ALREADY_EXISTS - This error will occur if an SD to be created already exists in the TEE. ERR_SD_NOT_EMPTY - This is reported if a target SD isn't empty. ERR_SDNAME_ALREADY_USED A TEE will return this error code if the new SD name already exists in the TEE. ERR_REQUEST_INVALID - This error will occur if the TEE meets any of the following conditions with a request message: (1) The request from a TAM has an invalid message structure; mandatory information is absent in the message. undefined member or structure is included. (2) TEE fails to verify signature of the message or fails to decrypt its contents. ERR_SPCERT_INVALID - If a new SP certificate for the SD to be updated is not valid, then the TEE will return this error code. ERR_TA_ALREADY_INSTALLED - While installing a TA, a TEE will return this error if the TA has already been installed in the SD. ERR_TA_INVALID - This error will occur when a TEE meets any of following conditions while checking validity of TA: (1) The TA binary has a format that the TEE can't recognize. (2) The TEE fails to decrypt the encoding of the TA binary and personalization data. (3) If an SP isn't registered with the SP SD where the TA will be installed. ERR_TA_NOT_FOUND - This error will occur when the target TA doesn't exist in the SD. ERR_TEE_FAIL - If the TEE fails to process a request because of an internal error, it will return this error code. ERR_TEE_RESOURCE_FULL - This error is reported when a device resource isn't available anymore such as storage space is full. Pei, et al. Expires April 26, 2019 [Page 78] Internet-Draft OTrP October 2018 ERR_TFW_NOT_TRUSTED - A TEE is responsible for determining that the underlying device firmware is trustworthy. If the TEE determines the TFW is not trustworthy, then this error will occur. ERR_TAM_NOT_TRUSTED - Before processing a request, a TEE needs to make sure whether the sender TAM is trustworthy by checking the validity of the TAM certificate, etc. If the TEE finds that the TAM is not trustworthy, then it will return this error code. ERR_UNSUPPORTED_CRYPTO_ALG - This error will occur if a TEE receives a request message encoded with cryptographic algorithms that the TEE doesn't support. ERR_UNSUPPORTED_MSG_VERSION - This error will occur if a TEE receives a message version that the TEE can't deal with. 13.1.2. OTrP Broker Error Code List ERR_AGENT_TEE_UNKNOWN - This error will occur if the receiver TEE is not supposed to receive the request. That will be determined by checking the TEE name or device id in the request message. ERR_AGENT_TEE_BUSY - The device TEE is busy. The request can be generally sent again to retry. ERR_AGENT_TEE_FAIL - The TEE fails to respond to a TAM request. The OTrP Broker will construct an error message in responding to the TAM's request. 14. Security Consideration 14.1. Cryptographic Strength The strength of the cryptographic algorithms, using the measure of 'bits of security' defined in NIST SP800-57 allowed for OTrP is: o At a minimum, 112 bits of security. The limiting factor for this is the RSA-2048 algorithm, which is indicated as providing 112 bits of symmetric key strength in SP800-57. It is important that RSA is supported in order to enhance the interoperability of the protocol. o The option exists to choose algorithms providing 128 bits of security. This requires using TEE devices that support ECC P256. The available algorithms and key sizes specified in this document are based on industry standards. Over time the recommended or allowed cryptographic algorithms may change. It is important that the OTrP Pei, et al. Expires April 26, 2019 [Page 79] Internet-Draft OTrP October 2018 allows for crypto-agility. In this specification, TAM and TEE can negotiate an agreed upon algorithm where both include their supported algorithm in OTrP message. 14.2. Message Security OTrP messages between the TAM and TEE are protected by message security using JWS and JWE. The 'Basic protocol profile' section of this document describes the algorithms used for this. All OTrP TEE devices and OTrP TAMs must meet the requirements of the basic profile. In the future additional 'profiles' can be added. PKI is used to ensure that the TEE will only communicate with a trusted TAM, and to ensure that the TAM will only communicate with a trusted TEE. 14.3. TEE Attestation It is important that the TAM can trust that it is talking to a trusted TEE. This is achieved through attestation. The TEE has a private key and certificate built into it at manufacture, which is used to sign data supplied by the TAM. This allows the TAM to verify that the TEE is trusted. It is also important that the TFW (trusted firmware) can be checked. The TFW has a private key and certificate built into it at manufacture, which allows the TEE to check that that the TFW is trusted. The GetDeviceState message therefore allows the TAM to check that it trusts the TEE, and the TEE at this point will check whether it trusts the TFW. 14.4. TA Protection A TA will be delivered in an encrypted form. This encryption is an additional layer within the message encryption described in the Section 11 of this document. The TA binary is encrypted for each target device with the device's TEE SP AIK public key. A TAM can either do this encryption itself or provide the TEE SP AIK public key to an SP such that the SP encrypts the encrypted TA for distribution to the TEE. Pei, et al. Expires April 26, 2019 [Page 80] Internet-Draft OTrP October 2018 The encryption algorithm can use a random AES 256 key "taek" with a 16 byte random IV, and the "taek" is encrypted by the "TEE SP AIK public key". The following encrypted TA data structure is expected by a TEE: "encrypted_ta_bin": { "key": "", "iv": ", "alg": "AESCBC", "cipherdata": "" } 14.5. TA Personalization Data An SP or TAM can supply personalization data for a TA to initialize for a device. Such data is passed through an InstallTA command from a TAM. The personalization data itself is (or can be) opaque to the TAM. The data can be from the SP without being revealed to the TAM. The data is sent in an encrypted manner in a request to a device such that only the device can decrypt. A device's TEE SP AIK public key for an SP is used to encrypt the data. Here JWE enveloping is used to carry all encryption key parameters along with encrypted data. "encrypted_ta_data": { // "TA personalization data" "key": "", "iv": "", "alg": "AESCBC", "cipherdata": "" } 14.6. TA Trust Check at TEE A TA binary is signed by a TA signer certificate. This TA signing certificate/private key belongs to the SP, and may be self-signed (i.e., it need not participate in a trust hierarchy). It is the responsibility of the TAM to only allow verified TAs from trusted SPs into the system. Delivery of that TA to the TEE is then the responsibility of the TEE, using the security mechanisms provided by the OTrP. We allow a way for an (untrusted) application to check the trustworthiness of a TA. OTrP Broker has a function to allow a Client Application to query the information about a TA. Pei, et al. Expires April 26, 2019 [Page 81] Internet-Draft OTrP October 2018 An application in the Rich O/S may perform verification of the TA by verifying the signature of the TA. The GetTAInformation function is available to return the TEE supplied TA signer and TAM signer information to the application. An application can do additional trust checks on the certificate returned for this TA. It might trust the TAM, or require additional SP signer trust chaining. 14.7. One TA Multiple SP Case A TA for multiple SPs must have a different identifier per SP. A TA will be installed in a different SD for each respective SP. 14.8. OTrP Broker Trust Model An OTrP Broker could be malware in the vulnerable REE. A Client Application will connect its TAM provider for required TA installation. It gets command messages from the TAM, and passes the message to the OTrP Broker. The OTrP is a conduit for enabling the TAM to communicate with the device's TEE to manage SDs and TAs. All TAM messages are signed and sensitive data is encrypted such that the OTrP Broker cannot modify or capture sensitive data. 14.9. OCSP Stapling Data for TAM Signed Messages The GetDeviceStateRequest message from a TAM to a TEE shall include OCSP stapling data for the TAM's signer certificate and for intermediate CA certificates up to the root certificate so that the TEE can verify the signer certificate's revocation status. A certificate revocation status check on a TA signer certificate is OPTIONAL by a TEE. A TAM is responsible for vetting a TA and the SP before it distributes them to devices. A TEE will trust a TA signer certificate's validation status done by a TAM when it trusts the TAM. 14.10. Data Protection at TAM and TEE The TEE implementation provides protection of data on the device. It is the responsibility of the TAM to protect data on its servers. 14.11. Privacy Consideration Devices are issued with a unique TEE certificate to attest the device's validity. This uniqueness also creates a privacy and tracking risk that must be mitigated. Pei, et al. Expires April 26, 2019 [Page 82] Internet-Draft OTrP October 2018 The TEE will only release the TEE certificate to a trusted TAM (it must verify the TAM certificate before proceeding). OTrP is designed such that only a TAM can obtain the TEE device certificate and firmware certificate - the GetDeviceState message requires signature checks to validate the TAM is trusted, and OTrP delivers the device's certificate(s) encrypted such that only that TAM can decrypt the response. A Client Application will never see the device certificate. An SP-specific TEE SP AIK (TEE SP Anonymous Key) is generated by the protocol for Client Applications. This provides a way for the Client Application to validate some data that the TEE may send without requiring the TEE device certificate to be released to the client device rich O/S , and to optionally allow an SP to encrypt a TA for a target device without the SP needing to be supplied with the TEE device certificate. 14.12. Threat Mitigation A rogue application may perform excessive TA loading. An OTrP Broker implementation should protect against excessive calls. Rogue applications might request excessive SD creation. The TAM is responsible to ensure this is properly guarded against. Rogue OTrP Broker could replay or send TAM messages out of sequence: e.g., a TAM sends update1 and update2. The OTrP Broker replays update2 and update1 again, creating an unexpected result that a client wants. "dsihash" is used to mitigate this. The TEE MUST store DSI state and check that the DSI state matches before it does another update. Concurrent calls from a TAM to a TEE MUST be handled properly by a TEE. If multiple concurrent TAM operations take place, these could fail due to the "dsihash" being modified by another concurrent operation. The TEE is responsible for resolve any locking such that one application cannot lock other applications from using the TEE, except for a short term duration of the TAM operation taking place. For example, an OTrP operation that starts but never completes (e.g. loss of connectivity) must not prevent subsequent OTrP messages from being executed. 14.13. Compromised CA A root CA for TAM certificates might get compromised. Some TEE trust anchor update mechanism is expected from device OEMs. A compromised intermediate CA is covered by OCSP stapling and OCSP validation check Pei, et al. Expires April 26, 2019 [Page 83] Internet-Draft OTrP October 2018 in the protocol. A TEE should validate certificate revocation about a TAM certificate chain. If the root CA of some TEE device certificates is compromised, these devices might be rejected by a TAM, which is a decision of the TAM implementation and policy choice. Any intermediate CA for TEE device certificates SHOULD be validated by TAM with a Certificate Revocation List (CRL) or Online Certificate Status Protocol (OCSP) method. 14.14. Compromised TAM The TEE SHOULD use validation of the supplied TAM certificates and OCSP stapled data to validate that the TAM is trustworthy. Since PKI is used, the integrity of the clock within the TEE determines the ability of the TEE to reject an expired TAM certificate, or revoked TAM certificate. Since OCSP stapling includes signature generation time, certificate validity dates are compared to the current time. 14.15. Certificate Renewal TFW and TEE device certificates are expected to be long lived, longer than the lifetime of a device. A TAM certificate usually has a moderate lifetime of 2 to 5 years. A TAM should get renewed or rekeyed certificates. The root CA certificates for a TAM, which are embedded into the trust anchor store in a device, should have long lifetimes that don't require device trust anchor update. On the other hand, it is imperative that OEMs or device providers plan for support of trust anchor update in their shipped devices. 15. Acknowledgements We thank Alin Mutu for his contribution to many discussion that helped to design the trust flow mechanisms, and the creation of the flow diagrams. We also thank the following people (in alphabetical order) for their input and review: Sangsu Baek, Rob Coombs, Dapeng Liu, Dave Thaler, and Pengfei Zhao. 16. References 16.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . Pei, et al. Expires April 26, 2019 [Page 84] Internet-Draft OTrP October 2018 [RFC4648] Josefsson, S., "The Base16, Base32, and Base64 Data Encodings", RFC 4648, DOI 10.17487/RFC4648, October 2006, . [RFC7515] Jones, M., Bradley, J., and N. Sakimura, "JSON Web Signature (JWS)", RFC 7515, DOI 10.17487/RFC7515, May 2015, . [RFC7516] Jones, M. and J. Hildebrand, "JSON Web Encryption (JWE)", RFC 7516, DOI 10.17487/RFC7516, May 2015, . [RFC7517] Jones, M., "JSON Web Key (JWK)", RFC 7517, DOI 10.17487/RFC7517, May 2015, . [RFC7518] Jones, M., "JSON Web Algorithms (JWA)", RFC 7518, DOI 10.17487/RFC7518, May 2015, . [TEEPArch] Pei, M., Tschofenig, H., Atyeo, A., and D. Liu, "Trusted Execution Environment Provisioning (TEEP) Architecture", 2018, . 16.2. Informative References [GPTEE] Global Platform, "Global Platform, GlobalPlatform Device Technology: TEE System Architecture, v1.0", 2013. [GPTEECLAPI] Global Platform, "Global Platform, GlobalPlatform Device Technology: TEE Client API Specification, v1.0", 2013. Appendix A. Sample Messages A.1. Sample Security Domain Management Messages A.1.1. Sample GetDeviceState A.1.1.1. Sample GetDeviceStateRequest The TAM builds a "GetDeviceStateTBSRequest" message. Pei, et al. Expires April 26, 2019 [Page 85] Internet-Draft OTrP October 2018 { "GetDeviceStateTBSRequest": { "ver": "1.0", "rid": "8C6F9DBB-FC39-435c-BC89-4D3614DA2F0B", "tid": "4F454A7F-002D-4157-884E-B0DD1A06A8AE", "ocspdat": "c2FtcGxlIG9jc3BkYXQgQjY0IGVuY29kZWQgQVNOMQ==", "icaocspdat": "c2FtcGxlIGljYW9jc3BkYXQgQjY0IGVuY29kZWQgQVNOMQ==", "supportedsigalgs": "RS256" } } The TAM signs "GetDeviceStateTBSRequest", creating "GetDeviceStateRequest" { "GetDeviceStateRequest": { "payload":" ewoJIkdldERldmljZVN0YXRlVEJTUmVxdWVzdCI6IHsKCQkidmVyIjogIjEuMCIsCgkJ InJpZCI6IHs4QzZGOURCQi1GQzM5LTQzNWMtQkM4OS00RDM2MTREQTJGMEJ9LAoJCSJ0 aWQiOiAiezRGNDU0QTdGLTAwMkQtNDE1Ny04ODRFLUIwREQxQTA2QThBRX0iLAoJCSJv Y3NwZGF0IjogImMyRnRjR3hsSUc5amMzQmtZWFFnUWpZMElHVnVZMjlrWldRZ1FWTk9N UT09IiwKCQkiaWNhb2NzcGRhdCI6ICJjMkZ0Y0d4bElHbGpZVzlqYzNCa1lYUWdRalkw SUdWdVkyOWtaV1FnUVZOT01RPT0iLAoJCSJzdXBwb3J0ZWRzaWdhbGdzIjogIlJTMjU2 IgoJfQp9", "protected": "eyJhbGciOiJSUzI1NiJ9", "header": { "x5c": ["ZXhhbXBsZSBBU04xIHNpZ25lciBjZXJ0aWZpY2F0ZQ==", "ZXhhbXBsZSBBU04xIENBIGNlcnRpZmljYXRl"] }, "signature":"c2FtcGxlIHNpZ25hdHVyZQ" } } A.1.1.2. Sample GetDeviceStateResponse The TAM sends "GetDeviceStateRequest" to the OTrP Broker The OTrP Broker obtains "dsi" from each TEE. (In this example there is a single TEE.) The TEE obtains signed "fwdata" from firmware. The TEE builds "dsi" - summarizing device state of the TEE. Pei, et al. Expires April 26, 2019 [Page 86] Internet-Draft OTrP October 2018 { "dsi": { "tfwdata": { "tbs": "ezRGNDU0QTdGLTAwMkQtNDE1Ny04ODRFLUIwREQxQTA2QThBRX0=", "cert": "ZXhhbXBsZSBGVyBjZXJ0aWZpY2F0ZQ==", "sigalg": "RS256", "sig": "c2FtcGxlIEZXIHNpZ25hdHVyZQ==" }, "tee": { "name": "Primary TEE", "ver": "1.0", "cert": "c2FtcGxlIFRFRSBjZXJ0aWZpY2F0ZQ==", "cacert": [ "c2FtcGxlIENBIGNlcnRpZmljYXRlIDE=", "c2FtcGxlIENBIGNlcnRpZmljYXRlIDI=" ], "sdlist": { "cnt": "1", "sd": [ { "name": "default.acmebank.com", "spid": "acmebank.com", "talist": [ { "taid": "acmebank.secure.banking", "taname": "Acme secure banking app" }, { "taid": "acmebank.loyalty.rewards", "taname": "Acme loyalty rewards app" } ] } ] }, "teeaiklist": [ { "spaik": "c2FtcGxlIEFTTjEgZW5jb2RlZCBQS0NTMSBwdWJsaWNrZXk=", "spaiktype": "RSA", "spid": "acmebank.com" } ] } } } The TEE encrypts "dsi", and embeds it into a "GetDeviceTEEStateTBSResponse" message. Pei, et al. Expires April 26, 2019 [Page 87] Internet-Draft OTrP October 2018 { "GetDeviceTEEStateTBSResponse": { "ver": "1.0", "status": "pass", "rid": "{8C6F9DBB-FC39-435c-BC89-4D3614DA2F0B}", "tid": "{4F454A7F-002D-4157-884E-B0DD1A06A8AE}", "signerreq":"false", "edsi": { "protected": "eyJlbmMiOiJBMTI4Q0JDLUhTMjU2In0K", "recipients": [ { "header": { "alg": "RSA1_5" }, "encrypted_key": " QUVTMTI4IChDRUspIGtleSwgZW5jcnlwdGVkIHdpdGggVFNNIFJTQSBwdWJsaWMg a2V5LCB1c2luZyBSU0ExXzUgcGFkZGluZw" } ], "iv": "ySGmfZ69YlcEilNr5_SGbA", "ciphertext": " c2FtcGxlIGRzaSBkYXRhIGVuY3J5cHRlZCB3aXRoIEFFUzEyOCBrZXkgZnJvbSByZW NpcGllbnRzLmVuY3J5cHRlZF9rZXk", "tag": "c2FtcGxlIGF1dGhlbnRpY2F0aW9uIHRhZw" } } } The TEE signs "GetDeviceTEEStateTBSResponse" and returns it to the OTrP Broker. The OTrP Broker encodes "GetDeviceTEEStateResponse" into an array to form "GetDeviceStateResponse". Pei, et al. Expires April 26, 2019 [Page 88] Internet-Draft OTrP October 2018 { "GetDeviceStateResponse": [ { "GetDeviceTEEStateResponse": { "payload": " ewogICJHZXREZXZpY2VURUVTdGF0ZVRCU1Jlc3BvbnNlIjogewogICAgInZlciI6 ICIxLjAiLAogICAgInN0YXR1cyI6ICJwYXNzIiwKICAgICJyaWQiOiAiezhDNkY5 REJCLUZDMzktNDM1Yy1CQzg5LTREMzYxNERBMkYwQn0iLAogICAgInRpZCI6ICJ7 NEY0NTRBN0YtMDAyRC00MTU3LTg4NEUtQjBERDFBMDZBOEFFfSIsCgkic2lnbmVy cmVxIjoiZmFsc2UiLAogICAgImVkc2kiOiB7CiAgICAgICJwcm90ZWN0ZWQiOiAi ZXlKbGJtTWlPaUpCTVRJNFEwSkRMVWhUTWpVMkluMEsiLAogICAgICAicmVjaXBp ZW50cyI6IFsKICAgICAgICB7CiAgICAgICAgICAiaGVhZGVyIjogewogICAgICAg ICAgImFsZyI6ICJSU0ExXzUiCiAgICAgICAgfSwKICAgICAgICAiZW5jcnlwdGVk X2tleSI6CiAgICAgICAgIgogICAgICAgIFFVVlRNVEk0SUNoRFJVc3BJR3RsZVN3 Z1pXNWpjbmx3ZEdWa0lIZHBkR2dnVkZOTklGSlRRU0J3ZFdKc2FXTWcKICAgICAg ICBhMlY1TENCMWMybHVaeUJTVTBFeFh6VWdjR0ZrWkdsdVp3IgogICAgICAgIH0K ICAgICAgXSwKICAgICAgIml2IjogInlTR21mWjY5WWxjRWlsTnI1X1NHYkEiLAog ICAgICAiY2lwaGVydGV4dCI6CiAgICAgICIKICAgICAgYzJGdGNHeGxJR1J6YVNC a1lYUmhJR1Z1WTNKNWNIUmxaQ0IzYVhSb0lFRkZVekV5T0NCclpYa2dabkp2YlNC eVpXCiAgICAgIE5wY0dsbGJuUnpMbVZ1WTNKNWNIUmxaRjlyWlhrIiwKICAgICAg InRhZyI6ICJjMkZ0Y0d4bElHRjFkR2hsYm5ScFkyRjBhVzl1SUhSaFp3IgogICAg fQogIH0KfQ", "protected": "eyJhbGciOiJSUzI1NiJ9", "signature": "c2FtcGxlIHNpZ25hdHVyZQ" } } ] } The TEE returns "GetDeviceStateResponse" back to the OTrP Broker, which returns message back to the TAM. A.1.2. Sample CreateSD A.1.2.1. Sample CreateSDRequest Pei, et al. Expires April 26, 2019 [Page 89] Internet-Draft OTrP October 2018 { "CreateSDTBSRequest": { "ver":"1.0", "rid":"req-01", "tid":"tran-01", "tee":"SecuriTEE", "nextdsi":"false", "dsihash":"Iu-c0-fGrpMmzbbtiWI1U8u7wMJE7IK8wkJpsVuf2js", "content":{ "spid":"bank.com", "sdname":"sd.bank.com", "spcert":"MIIDFjCCAn- gAwIBAgIJAIk0Tat0tquDMA0GCSqGSIb3DQEBBQUAMGwxCzAJBgNVBAYTAkTAMQ4wD AYDVQQIDAVTZW91bDESMBAGA1UEBwwJR3Vyby1kb25nMRAwDgYDVQQKDAdTb2xhY2l hMRAwDgYDVQQLDAdTb2xhY2lhMRUwEwYDVQQDDAxTb2xhLWNpYS5jb20wHhcNMTUwN zAyMDg1MTU3WhcNMjAwNjMwMDg1MTU3WjBsMQswCQYDVQQGEwJLUjEOMAwGA1UECAw FU2VvdWwxEjAQBgNVBAcMCUd1cm8tZG9uZzEQMA4GA1UECgwHU29sYWNpYTEQMA4GA 1UECwwHU29sYWNpYTEVMBMGA1UEAwwMU29sYS1jaWEuY29tMIGfMA0GCSqGSIb3DQE BAQUAA4GNADCBiQKBgQDYWLrFf2OFMEciwSYsyhaLY4kslaWcXA0hCWJRaFzt5mU- lpSJ4jeu92inBbsXcI8PfRbaItsgW1TD1Wg4gQH4MX_YtaBoOepE-- 3JoZZyPyCWS3AaLYWrDmqFXdbzaO1i8GxB7zz0gWw55bZ9jyzcl5gQzWSqMRpx_dca d2SP2wIDAQABo4G_MIG8MIGGBgNVHSMEfzB9oXCkbjBsMQswCQYDVQQGEwJLUjEOMA wGA1UECAwFU2VvdWwxEjAQBgNVBAcMCUd1cm8tZG9uZzEQMA4GA1UECgwHU29sYWNp YTEQMA4GA1UECwwHU29sYWNpYTEVMBMGA1UEAwwMU29sYS1jaWEuY29tggkAiTRNq3 S2q4MwCQYDVR0TBAIwADAOBgNVHQ8BAf8EBAMCBsAwFgYDVR0lAQH_BAwwCgYIKwYB BQUHAwMwDQYJKoZIhvcNAQEFBQADgYEAEFMhRwEQ- LDa9O7P1N0mcLORpo6fW3QuJfuXbRQRQGoXddXMKazI4VjbGaXhey7Bzvk6TZYDa- GRiZby1J47UPaDQR3UiDzVvXwCOU6S5yUhNJsW_BeMViYj4lssX28iPpNwLUCVm1QV THILI6afLCRWXXclc1L5KGY290OwIdQ", "tamid":"TAM_x.acme.com", "did":"zAHkb0-SQh9U_OT8mR5dB-tygcqpUJ9_x07pIiw8WoM" } } } Below is a sample message after the content is encrypted and encoded { "CreateSDRequest": { "payload":" eyJDcmVhdGVTRFRCU1JlcXVlc3QiOnsidmVyIjoiMS4wIiwicmlkIjoicmVxLTAxIiwidG lkIjoidHJhbi0wMSIsInRlZSI6IlNlY3VyaVRFRSIsIm5leHRkc2kiOiJmYWxzZSIsImRz aWhhc2giOiIyMmVmOWNkM2U3YzZhZTkzMjZjZGI2ZWQ4OTYyMzU1M2NiYmJjMGMyNDRlYz gyYmNjMjQyNjliMTViOWZkYTNiIiwiY29udGVudCI6eyJwcm90ZWN0ZWQiOiJlLUtBbkdW dVktS0FuVHJpZ0p4Qk1USTRRMEpETFVoVE1qVTI0b0NkZlEiLCJyZWNpcGllbnRzIjpbey JoZWFkZXIiOnsiYWxnIjoiUlNBMV81In0sImVuY3J5cHRlZF9rZXkiOiJTUzE2NTl4Q2FJ c1dUeUlsVTZPLUVsZzU4UUhvT1pCekxVRGptVG9vanBaWE54TVpBakRMcWtaSTdEUzhOVG FIWHcxczFvZjgydVhsM0d6NlVWMkRoZDJ3R2l6Y2VEdGtXc1RwZDg4QVYwaWpEYTNXa3lk Pei, et al. Expires April 26, 2019 [Page 90] Internet-Draft OTrP October 2018 dEpSVmlPOGdkSlEtV29NSUVJRUxzVGthblZCb25wQkF4ZHE0ckVMbl9TZlliaFg4Zm9ub2 gxUVUifV0sIml2IjoiQXhZOERDdERhR2xzYkdsamIzUm9aUSIsImNpcGhlcnRleHQiOiI1 bmVWZXdndm55UXprR3hZeWw5QlFrZTJVNjVaOHp4NDdlb3NzM3FETy0xY2FfNEpFY3NLcj ZhNjF5QzBUb0doYnJOQWJXbVRSemMwSXB5bTF0ZjdGemp4UlhBaTZBYnVSM2gzSUpRS1Bj UUVvRUlkZ2tWX0NaZTM2eTBkVDBpRFBMclg0QzFkb0dmMEdvaWViRC1yVUg1VUtEY3BsTW 9lTjZvUnFyd0dnNUhxLTJXM3B4MUlzY0h4SktRZm11dkYxMTJ4ajBmZFNZX0N2WFE1NTJr TVRDUW1ZbzRPaGF2R0ZvaG9TZVVnaGZSVG1LYWp3OThkTzdhREdrUEpRUlBtYVVHWllEMW JXd01nMXFRV3RPd19EZlIyZDNzTzVUN0pQMDJDUFprVXBiQ3dZYVcybW9HN1c2Zlc2U3V5 Q2lpd2pQWmZSQmIzSktTVTFTd1kxYXZvdW02OWctaDB6by12TGZvbHRrWFV2LVdPTXZTY0 JzR25NRzZYZnMzbXlTWnJ1WTNRR09wVVRzdjFCQ0JqSTJpdjkwb2U2aXFCcVpxQVBxbzdi ajYwVlJGQzZPTlNLZExGQTIyU3pqRHo1dmtnTXNEaHkwSzlDeVhYN1Z6MkNLTXJvQjNiUE xFZF9abTZuVWlkTFN5cVJ5cXJxTmVnN1lmQng3aV93X0dzRW9rX1VYZXd6RGtneHp6RjZj XzZ6S0s3UFktVnVmYUo0Z2dHZmlpOHEwMm9RZ1VEZTB2Vm1FWDc0c2VQX2RxakVpZVVOYm xBZE9sS2dBWlFGdEs4dy1xVUMzSzVGTjRoUG9yeDc2b3lPVUpOQTVFZVV2Qy1jR2tMcTNQ UG1GRmQyaUtOTElCTEJzVWl6c1h3RERvZVA5SmktWGt5ZEQtREN1SHdpcno0OEdNNWVLSj Q5WVdqRUtFQko2T01NNUNmZHZ4cDNmVG1uUTdfTXcwZ3FZVDRiOUJJSnBfWjA3TTctNUpE emg0czhyU3dsQzFXU3V2RmhRWlJCcXJtX2RaUlRIb0VaZldXc1VCSWVNWWdxNG1zb0JqTj NXSzhnRWYwZGI5a3Z6UG9LYmpJRy10UUE2R2l1X3pHaFVfLXFBV1lLemVKMDZ6djRIWlBO dHktQXRyTGF0WGhtUTdOQlVrX0hvbjdOUWxhU1g1ZHVNVmN4bGs1ZHVrWFZNMDgxa09wYV kzbDliQVFfYVhTM0FNaFFTTVVsT3dnTDZJazFPYVpaTGFMLUE3ejlITnlESmFEWTVhakZK TWFDV1lfOG94YlNoQUktNXA2MmNuT0xzV0dNWWNKTlBGVTZpcWlMR19oc3JfNlNKMURhbD VtQ0YycnBJLUItMlhuckxZR01ZS0NEZ2V2dGFnbi1DVUV6RURwR3ozQ2VLcWdQU0Vqd3BK N0M3NXduYTlCSmtTUkpOdDNla3hoWElrcnNEazRHVVpMSDdQYzFYZHdRTXhxdWpzNmxJSV EycjM1NWEtVkotWHdPcFpfY3RPdW96LTA4WHdYQ3RkTEliSFFVTG40RjlMRTRtanU0dUxS bjNSc043WWZ1S3dCVmVEZDJ6R3NBY0s5SVlDa3hOaDk3dDluYW1iMDZqSXVoWXF5QkhWRU 9nTkhici1rMDY1bW9OVk5lVVUyMm5OdVNKS0ZxVnIxT0dKNGVfNXkzYkNwTmxTeEFPV1Bn RnJzU0Flc2JJOWw4eVJtVTAwenJYdGc4OWt5SjlCcXN2eXA1RE8wX2FtS1JyMXB1MVJVWF lFZzB2ampKS1FSdDVZbXRUNFJzaWpqdGRDWDg3UUxJaUdSY0hDdlJzUzZSdDJESmNYR1ht UGQyc0ZmNUZyNnJnMkFzX3BmUHN3cnF1WlAxbVFLc3RPMFVkTXpqMTlyb2N1NHVxVXlHUD lWWU54cHVnWVdNSjRYb1dRelJtWGNTUEJ4VEtnenFPS2s3UnRzWWVMNXl4LVM4NjV0cHVz dTA0bXpzYUJRZ21od1ZFVXBRdWNrcG1YWkNLNHlJUXktaHNFQUlJSmVxdFB3dVAySXF0X2 I5dlk0bzExeXdzeXhzdmp2RnNKN0VVZU1MaGE2R2dSanBSbnU5RWIzRnlJZ0U5M0VVNEEw T0lUMWlOSGNRYWc0eWtOc3dPdkxQbjZIZ21zQ05ESlgwekc2RlFDMTZRdjBSQ25SVTdfV2 VvblhSTUZwUzZRZ1JiSk45R1NMckN5bklJSWxUcDBxNHBaS05zM0tqQ2tMUzJrb3Bhd2Y0 WF9BUllmTko3a0s5eW5BR0dCcktnUWJNRWVxUEFmMDBKMlYtVXpuU1JMZmQ4SGs3Y2JEdk 5RQlhHQW9BR0ViaGRwVUc0RXFwMlVyQko3dEtyUUVSRlh4RTVsOFNHY2czQ1RmN2Zoazdx VEFBVjVsWEFnOUtOUDF1c1ZRZk1fUlBleHFNTG9WQVVKV2syQkF6WF9uSEhkVVhaSVBIOG hLeDctdEFRV0dTWUd0R2FmanZJZzI2c082TzloQWZVd3BpSV90MzF6SkZORDU0OTZURHBz QmNnd2dMLU1UcVhCRUJ2NEhvQld5SG1DVjVFMUwiLCJ0YWciOiJkbXlEeWZJVlNJUi1Ren ExOEgybFRIeEMxbl9HZEtrdnZNMDJUcHdsYzQwIn19fQ", "protected":"e-KAnGFsZ-KAnTrigJxSUzI1NuKAnX0", //RSAwithSHA256 "header": { "kid":"e9bc097a-ce51-4036-9562-d2ade882db0d", "signer":" MIIC3zCCAkigAwIBAgIJAJf2fFkE1BYOMA0GCSqGSIb3DQEBBQUAMFoxCzAJBgNVBA YTAlVTMRMwEQYDVQQIDApDYWxpZm9ybmlhMRMwEQYDVQQHDApDYWxpZm9ybmlhMSEw HwYDVQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGQwHhcNMTUwNzAyMDkwMTE4Wh cNMjAwNjMwMDkwMTE4WjBaMQswCQYDVQQGEwJVUzETMBEGA1UECAwKQ2FsaWZvcm5p Pei, et al. Expires April 26, 2019 [Page 91] Internet-Draft OTrP October 2018 YTETMBEGA1UEBwwKQ2FsaWZvcm5pYTEhMB8GA1UECgwYSW50ZXJuZXQgV2lkZ2l0cy BQdHkgTHRkMIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC8ZtxM1bYickpgSVG- meHInI3f_chlMBdL8l7daOEztSs_a6GLqmvSu- AoDpTsfEd4EazdMBp5fmgLRGdCYMcI6bgpO94h5CCnlj8xFKPq7qGixdwGUA6b_ZI3 c4cZ8eu73VMNrrn_z3WTZlExlpT9XVj- ivhfJ4a6T20EtMM5qwIDAQABo4GsMIGpMHQGA1UdIwRtMGuhXqRcMFoxCzAJBgNVBA YTAlVTMRMwEQYDVQQIDApDYWxpZm9ybmlhMRMwEQYDVQQHDApDYWxpZm9ybmlhMSEw HwYDVQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGSCCQCX9nxZBNQWDjAJBgNVHR MEAjAAMA4GA1UdDwEB_wQEAwIGwDAWBgNVHSUBAf8EDDAKBggrBgEFBQcDAzANBgkq hkiG9w0BAQUFAAOBgQAGkz9QpoxghZUWT4ivem4cIckfxzTBBiPHCjrrjB2X8Ktn8G SZ1MdyIZV8fwdEmD90IvtMHgtzK- 9wo6Aibj_rVIpxGb7trP82uzc2X8VwYnQbuqQyzofQvcwZHLYplvi95pZ5fVrJvnYA UBFyfrdT5GjqL1nqH3a_Y3QPscuCjg" }, "signature":"nuQUsCTEBLeaRzuwd7q1iPIYEJ2eJfurO5sT5Y- N03zFRcv1jvrqMHtx_pw0Y9YWjmpoWfpfelhwGEko9SgeeBnznmkZbp7kjS6MmX4CKz 9OApe3-VI7yL9Yp0WNdRh3425eYfuapCy3lcXFln5JBAUnU_OzUg3RWxcU_yGnFsw" } } A.1.2.2. Sample CreateSDResponse { "CreateSDTBSResponse": { "ver":"1.0", "status":"pass", "rid":"req-01", "tid":"tran-01", "content":{ "did":"zAHkb0-SQh9U_OT8mR5dB-tygcqpUJ9_x07pIiw8WoM", "sdname":"sd.bank.com", "teespaik":"AQABjY9KiwH3hkMmSAAN6CLXot525U85WNlWKAQz5TOdfe_CM8h- X6_EHX1gOXoyRXaBiKMqWb0YZLCABTw1ytdXy2kWa525imRho8Vqn6HDGsJDZPDru9 GnZR8pZX5ge_dWXB_uljMvDttc5iAWEJ8ZgcpLGtBTGLZnQoQbjtn1lIE", } } } Below is the response message after the content is encrypted and encoded. { "CreateSDResponse": { "payload":" eyJDcmVhdGVTRFRCU1Jlc3BvbnNlIjp7InZlciI6IjEuMCIsInN0YXR1cyI6InBhc3Mi LCJyaWQiOiJyZXEtMDEiLCJ0aWQiOiJ0cmFuLTAxIiwiY29udGVudCI6eyJwcm90ZWN0 ZWQiOiJlLUtBbkdWdVktS0FuVHJpZ0p4Qk1USTRRMEpETFVoVE1qVTI0b0NkZlEiLCJy ZWNpcGllbnRzIjpbeyJoZWFkZXIiOnsiYWxnIjoiUlNBMV81In0sImVuY3J5cHRlZF9r Pei, et al. Expires April 26, 2019 [Page 92] Internet-Draft OTrP October 2018 ZXkiOiJOX0I4R3pldUlfN2hwd0wwTFpHSTkxVWVBbmxJRkJfcndmZU1yZERrWnFGak1s VVhjdlI0XzhhOGhyeFI4SXR3aEtFZnVfRWVLRDBQb0dqQ2pCSHcxdG1ULUN6eWhsbW5v Slk3LXllWnZzRkRpc2VNTkd0eGE0OGZJYUs2VWx5NUZMYXBCZVc5T1I5bmktOU9GQV9j aFVuWWl3b2Q4ZTJFa0Vpd0JEZ1EzMk0ifV0sIml2IjoiQXhZOERDdERhR2xzYkdsamIz Um9aUSIsImNpcGhlcnRleHQiOiJsalh6Wk5JTmR1WjFaMXJHVElkTjBiVUp1RDRVV2xT QVptLWd6YnJINFVDYy1jMEFQenMtMWdWSFk4NTRUR3VMYkdyRmVHcDFqM2Fsb1lacWZp ZnE4aEt3Ty16RFlBN2tmVFhBZHp6czM4em9xeG4zbHoyM2w1RUlGUWhrOHBRWTRYTHRW M3ZBQWlNYnlrQ1Q3VS1CWDdWcjBacVNhYWZTQVZ4OFBLQ1RIU3hHN3hHVko0NkxxRzJS RE54WXQ4RC1SQ3lZUi1zRTM0MUFKZldEc2FLaGRRbzJXcjNVN1hTOWFqaXJtWjdqTlJ4 cVRodHJBRWlIY1ctOEJMdVFHWEZ1YUhLMTZrenJKUGl4d0VXbzJ4cmw4cmkwc3ZRcHpl Z2M3MEt2Z0I0NUVaNHZiNXR0YlUya25hN185QU1Wcm4wLUJaQ1Bnb280MWlFblhuNVJn TXY2c2V2Y1JPQ2xHMnpWSjFoRkVLYjk2akEiLCJ0YWciOiIzOTZISTk4Uk1NQnR0eDlo ZUtsODROaVZLd0lJSzI0UEt2Z1RGYzFrbEJzIn19fQ", "protected": "e-KAnGFsZ-KAnTrigJxSUzI1NuKAnX0", "header": { "kid":"e9bc097a-ce51-4036-9562-d2ade882db0d", "signer":" MIIC3zCCAkigAwIBAgIJAJf2fFkE1BYOMA0GCSqGSIb3DQEBBQUAMFoxCzAJ BgNVBAYTAlVTMRMwEQYDVQQIDApDYWxpZm9ybmlhMRMwEQYDVQQHDApDYWxp Zm9ybmlhMSEwHwYDVQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGQwHhcN MTUwNzAyMDkwMTE4WhcNMjAwNjMwMDkwMTE4WjBaMQswCQYDVQQGEwJVUzET MBEGA1UECAwKQ2FsaWZvcm5pYTETMBEGA1UEBwwKQ2FsaWZvcm5pYTEhMB8G A1UECgwYSW50ZXJuZXQgV2lkZ2l0cyBQdHkgTHRkMIGfMA0GCSqGSIb3DQEB AQUAA4GNADCBiQKBgQC8ZtxM1bYickpgSVG- meHInI3f_chlMBdL8l7daOEztSs_a6GLqmvSu- AoDpTsfEd4EazdMBp5fmgLRGdCYMcI6bgpO94h5CCnlj8xFKPq7qGixdwGUA 6b_ZI3c4cZ8eu73VMNrrn_z3WTZlExlpT9XVj- ivhfJ4a6T20EtMM5qwIDAQABo4GsMIGpMHQGA1UdIwRtMGuhXqRcMFoxCzAJ BgNVBAYTAlVTMRMwEQYDVQQIDApDYWxpZm9ybmlhMRMwEQYDVQQHDApDYWxp Zm9ybmlhMSEwHwYDVQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGSCCQCX 9nxZBNQWDjAJBgNVHRMEAjAAMA4GA1UdDwEB_wQEAwIGwDAWBgNVHSUBAf8E DDAKBggrBgEFBQcDAzANBgkqhkiG9w0BAQUFAAOBgQAGkz9QpoxghZUWT4iv em4cIckfxzTBBiPHCjrrjB2X8Ktn8GSZ1MdyIZV8fwdEmD90IvtMHgtzK- 9wo6Aibj_rVIpxGb7trP82uzc2X8VwYnQbuqQyzofQvcwZHLYplvi95pZ5fV rJvnYAUBFyfrdT5GjqL1nqH3a_Y3QPscuCjg" }, "signature":"jnJtaB0vFFwrE-qKOR3Pu9pf2gNoI1s67GgPCTq0U- qrz97svKpuh32WgCP2MWCoQPEswsEX-nxhIx_siTe4zIPO1nBYn- R7b25rQaF87O8uAOOnBN5Yl2Jk3laIbs- hGE32aRZDhrVoyEdSvIFrT6AQqD20bIAZGqTR-zA-900" } } A.1.3. Sample UpdateSD Pei, et al. Expires April 26, 2019 [Page 93] Internet-Draft OTrP October 2018 A.1.3.1. Sample UpdateSDRequest { "UpdateSDTBSRequest": { "ver": "1.0", "rid": "1222DA7D-8993-41A4-AC02-8A2807B31A3A", "tid": "4F454A7F-002D-4157-884E-B0DD1A06A8AE", "tee": "Primary TEE ABC", "nextdsi": "false", "dsihash": " IsOvwpzDk8Onw4bCrsKTJsONwrbDrcKJYjVTw4vCu8OAw4JEw6zCgsK8w4JCacKxW8Kf w5o7", "content": { // NEEDS to BE ENCRYPTED "tamid": "id1.TAMxyz.com", "spid": "com.acmebank.spid1", "sdname": "com.acmebank.sdname1", "changes": { "newsdname": "com.acmebank.sdname2", "newspid": "com.acquirer.spid1", "spcert": "MIIDFjCCAn- gAwIBAgIJAIk0Tat0tquDMA0GCSqGSIb3DQEBBQUAMGwxCzAJBgNVBAYTAkTAMQ4 wDAYDVQQIDAVTZW91bDESMBAGA1UEBwwJR3Vyby1kb25nMRAwDgYDVQQKDAdTb2x hY2lhMRAwDgYDVQQLDAdTb2xhY2lhMRUwEwYDVQQDDAxTb2xhLWNpYS5jb20wHhc NMTUwNzAyMDg1MTU3WhcNMjAwNjMwMDg1MTU3WjBsMQswCQYDVQQGEwJLUjEOMAw GA1UECAwFU2VvdWwxEjAQBgNVBAcMCUd1cm8tZG9uZzEQMA4GA1UECgwHU29sYWN pYTEQMA4GA1UECwwHU29sYWNpYTEVMBMGA1UEAwwMU29sYS1jaWEuY29tMIGfMA0 GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDYWLrFf2OFMEciwSYsyhaLY4kslaWcXA0 hCWJRaFzt5mU- lpSJ4jeu92inBbsXcI8PfRbaItsgW1TD1Wg4gQH4MX_YtaBoOepE-- 3JoZZyPyCWS3AaLYWrDmqFXdbzaO1i8GxB7zz0gWw55bZ9jyzcl5gQzWSqMRpx_d cad2SP2wIDAQABo4G_MIG8MIGGBgNVHSMEfzB9oXCkbjBsMQswCQYDVQQGEwJLUj EOMAwGA1UECAwFU2VvdWwxEjAQBgNVBAcMCUd1cm8tZG9uZzEQMA4GA1UECgwHU2 9sYWNpYTEQMA4GA1UECwwHU29sYWNpYTEVMBMGA1UEAwwMU29sYS1jaWEuY29tgg kAiTRNq3S2q4MwCQYDVR0TBAIwADAOBgNVHQ8BAf8EBAMCBsAwFgYDVR0lAQH_BA wwCgYIKwYBBQUHAwMwDQYJKoZIhvcNAQEFBQADgYEAEFMhRwEQ- LDa9O7P1N0mcLORpo6fW3QuJfuXbRQRQGoXddXMKazI4VjbGaXhey7Bzvk6TZYDa - GRiZby1J47UPaDQR3UiDzVvXwCOU6S5yUhNJsW_BeMViYj4lssX28iPpNwLUCVm1 QVTHILI6afLCRWXXclc1L5KGY290OwIdQ", "renewteespaik": "0" } } } } Pei, et al. Expires April 26, 2019 [Page 94] Internet-Draft OTrP October 2018 A.1.3.2. Sample UpdateSDResponse { "UpdateSDTBSResponse": { "ver": "1.0", "status": "pass", "rid": "1222DA7D-8993-41A4-AC02-8A2807B31A3A", "tid": "4F454A7F-002D-4157-884E-B0DD1A06A8AE", "content": { "did": "MTZENTE5Qzc0Qzk0NkUxMzYxNzk0NjY4NTc3OTY4NTI=", "teespaik": "AQABjY9KiwH3hkMmSAAN6CLXot525U85WNlWKAQz5TOdfe_CM8h- X6_EHX1gOXoyRXaBiKMqWb0YZLCABTw1ytdXy2kWa525imRho8Vqn6HDGsJDZPDru9 GnZR8pZX5ge_dWXB_uljMvDttc5iAWEJ8ZgcpLGtBTGLZnQoQbjtn1lIE", "teespaiktype": "RSA" } } } A.1.4. Sample DeleteSD A.1.4.1. Sample DeleteSDRequest The TAM builds message - including data to be encrypted. { "DeleteSDTBSRequest": { "ver": "1.0", "rid": "{712551F5-DFB3-43f0-9A63-663440B91D49}", "tid": "{4F454A7F-002D-4157-884E-B0DD1A06A8AE}", "tee": "Primary TEE", "nextdsi": "false", "dsihash": "AAECAwQFBgcICQoLDA0ODwABAgMEBQYHCAkKCwwNDg8=", "content": ENCRYPTED { "tamid": "TAM1.com", "sdname": "default.acmebank.com", "deleteta": "1" } } } The TAM encrypts the "content". Pei, et al. Expires April 26, 2019 [Page 95] Internet-Draft OTrP October 2018 { "DeleteSDTBSRequest": { "ver": "1.0", "rid": "{712551F5-DFB3-43f0-9A63-663440B91D49}", "tid": "{4F454A7F-002D-4157-884E-B0DD1A06A8AE}", "tee": "Primary TEE", "nextdsi": "false", "dsihash": "AAECAwQFBgcICQoLDA0ODwABAgMEBQYHCAkKCwwNDg8=", "content": { "protected": "eyJlbmMiOiJBMTI4Q0JDLUhTMjU2In0", "recipients": [ { "header": { "alg": "RSA1_5" }, "encrypted_key": " QUVTMTI4IChDRUspIGtleSwgZW5jcnlwdGVkIHdpdGggVFNNIFJTQSBwdWJsaWMga2 V5LCB1c2luZyBSU0ExXzUgcGFkZGluZw" } ], "iv": "rWO5DVmQX9ogelMLBIogIA", "ciphertext": " c2FtcGxlIGRzaSBkYXRhIGVuY3J5cHRlZCB3aXRoIEFFUzEyOCBrZXkgZnJvbSByZWNp cGllbnRzLmVuY3J5cHRlZF9rZXk", "tag": "c2FtcGxlIGF1dGhlbnRpY2F0aW9uIHRhZw" } } } The TAM signs the "DeleteSDTBSRequest" to form a "DeleteSDRequest" Pei, et al. Expires April 26, 2019 [Page 96] Internet-Draft OTrP October 2018 { "DeleteSDRequest": { "payload":" ewoJIkRlbGV0ZVNEVEJTUmVxdWVzdCI6IHsKCQkidmVyIjogIjEuMCIsCgkJInJp ZCI6ICJ7NzEyNTUxRjUtREZCMy00M2YwLTlBNjMtNjYzNDQwQjkxRDQ5fSIsCgkJ InRpZCI6ICJ7NEY0NTRBN0YtMDAyRC00MTU3LTg4NEUtQjBERDFBMDZBOEFFfSIs CgkJInRlZSI6ICJQcmltYXJ5IFRFRSIsCgkJIm5leHRkc2kiOiAiZmFsc2UiLAoJ CSJkc2loYXNoIjogIkFBRUNBd1FGQmdjSUNRb0xEQTBPRHdBQkFnTUVCUVlIQ0Fr S0N3d05EZzg9IiwKCQkiY29udGVudCI6IHsKCQkJInByb3RlY3RlZCI6ICJleUps Ym1NaU9pSkJNVEk0UTBKRExVaFRNalUySW4wIiwKCQkJInJlY2lwaWVudHMiOiBb ewoJCQkJImhlYWRlciI6IHsKCQkJCQkiYWxnIjogIlJTQTFfNSIKCQkJCX0sCgkJ CQkiZW5jcnlwdGVkX2tleSI6ICJRVVZUTVRJNElDaERSVXNwSUd0bGVTd2daVzVq Y25sd2RHVmtJSGRwZEdnZ1ZGTk5JRkpUUVNCd2RXSnNhV01nYTJWNUxDQjFjMmx1 WnlCU1UwRXhYelVnY0dGa1pHbHVadyIKCQkJfV0sCgkJCSJpdiI6ICJyV081RFZt UVg5b2dlbE1MQklvZ0lBIiwKCQkJImNpcGhlcnRleHQiOiAiYzJGdGNHeGxJR1J6 YVNCa1lYUmhJR1Z1WTNKNWNIUmxaQ0IzYVhSb0lFRkZVekV5T0NCclpYa2dabkp2 YlNCeVpXTnBjR2xsYm5SekxtVnVZM0o1Y0hSbFpGOXJaWGsiLAoJCQkidGFnIjog ImMyRnRjR3hsSUdGMWRHaGxiblJwWTJGMGFXOXVJSFJoWnciCgkJfQoJfQp9", "protected":"eyJhbGciOiJSUzI1NiJ9", "header": { "x5c": ["ZXhhbXBsZSBBU04xIHNpZ25lciBjZXJ0aWZpY2F0ZQ==", "ZXhhbXBsZSBBU04xIENBIGNlcnRpZmljYXRl"] }, "signature":"c2FtcGxlIHNpZ25hdHVyZQ" } } A.1.4.2. Sample DeleteSDResponse The TEE creates a "DeleteSDTBSResponse" to respond to the "DeleteSDRequest" message from the TAM, including data to be encrypted. { "DeleteSDTBSResponse": { "ver": "1.0", "status": "pass", "rid": "{712551F5-DFB3-43f0-9A63-663440B91D49}", "tid": "{4F454A7F-002D-4157-884E-B0DD1A06A8AE}", "content": ENCRYPTED { "did": "MTZENTE5Qzc0Qzk0NkUxMzYxNzk0NjY4NTc3OTY4NTI=", } } } The TEE encrypts the "content" for the TAM. Pei, et al. Expires April 26, 2019 [Page 97] Internet-Draft OTrP October 2018 { "DeleteSDTBSResponse": { "ver": "1.0", "status": "pass", "rid": "{712551F5-DFB3-43f0-9A63-663440B91D49}", "tid": "{4F454A7F-002D-4157-884E-B0DD1A06A8AE}", "content": { "protected": "eyJlbmMiOiJBMTI4Q0JDLUhTMjU2In0K", "recipients": [ { "header": { "alg": "RSA1_5" }, "encrypted_key": " QUVTMTI4IChDRUspIGtleSwgZW5jcnlwdGVkIHdpdGggVFNNIFJTQSBwdWJsaWMg a2V5LCB1c2luZyBSU0ExXzUgcGFkZGluZw" } ], "iv": "ySGmfZ69YlcEilNr5_SGbA", "ciphertext": " c2FtcGxlIGRzaSBkYXRhIGVuY3J5cHRlZCB3aXRoIEFFUzEyOCBrZXkgZnJvbSByZW NpcGllbnRzLmVuY3J5cHRlZF9rZXk", "tag": "c2FtcGxlIGF1dGhlbnRpY2F0aW9uIHRhZw" } } } The TEE signs "DeleteSDTBSResponse" to form a "DeleteSDResponse" Pei, et al. Expires April 26, 2019 [Page 98] Internet-Draft OTrP October 2018 { "DeleteSDResponse": { "payload":" ewoJIkRlbGV0ZVNEVEJTUmVzcG9uc2UiOiB7CgkJInZlciI6ICIxLjAiLAoJCSJz dGF0dXMiOiAicGFzcyIsCgkJInJpZCI6ICJ7NzEyNTUxRjUtREZCMy00M2YwLTlB NjMtNjYzNDQwQjkxRDQ5fSIsCgkJInRpZCI6ICJ7NEY0NTRBN0YtMDAyRC00MTU3 LTg4NEUtQjBERDFBMDZBOEFFfSIsCgkJImNvbnRlbnQiOiB7CgkJCSJwcm90ZWN0 ZWQiOiAiZXlKbGJtTWlPaUpCTVRJNFEwSkRMVWhUTWpVMkluMEsiLAoJCQkicmVj aXBpZW50cyI6IFt7CgkJCQkiaGVhZGVyIjogewoJCQkJCSJhbGciOiAiUlNBMV81 IgoJCQkJfSwKCQkJCSJlbmNyeXB0ZWRfa2V5IjogIlFVVlRNVEk0SUNoRFJVc3BJ R3RsZVN3Z1pXNWpjbmx3ZEdWa0lIZHBkR2dnVkZOTklGSlRRU0J3ZFdKc2FXTWdh MlY1TENCMWMybHVaeUJTVTBFeFh6VWdjR0ZrWkdsdVp3IgoJCQl9XSwKCQkJIml2 IjogInlTR21mWjY5WWxjRWlsTnI1X1NHYkEiLAoJCQkiY2lwaGVydGV4dCI6ICJj MkZ0Y0d4bElHUnphU0JrWVhSaElHVnVZM0o1Y0hSbFpDQjNhWFJvSUVGRlV6RXlP Q0JyWlhrZ1puSnZiU0J5WldOcGNHbGxiblJ6TG1WdVkzSjVjSFJsWkY5clpYayIs CgkJCSJ0YWciOiAiYzJGdGNHeGxJR0YxZEdobGJuUnBZMkYwYVc5dUlIUmhadyIK CQl9Cgl9Cn0", "protected":"eyJhbGciOiJSUzI1NiJ9", "signature":"c2FtcGxlIHNpZ25hdHVyZQ" } } The TEE returns "DeleteSDResponse" back to the OTrP Broker, which returns the message back to the TAM. A.2. Sample TA Management Messages A.2.1. Sample InstallTA A.2.1.1. Sample InstallTARequest Pei, et al. Expires April 26, 2019 [Page 99] Internet-Draft OTrP October 2018 { "InstallTATBSRequest": { "ver": "1.0", "rid": "24BEB059-0AED-42A6-A381-817DFB7A1207", "tid": "4F454A7F-002D-4157-884E-B0DD1A06A8AE", "tee": "Primary TEE ABC", "nextdsi": "true", "dsihash": " IsOvwpzDk8Onw4bCrsKTJsONwrbDrcKJYjVTw4vCu8OAw4JEw6zCgsK8w4JCacKxW8Kf w5o7", "content": { "tamid": "id1.TAMxyz.com", "spid": "com.acmebank.spid1", "sdname": "com.acmebank.sdname1", "taid": "com.acmebank.taid.banking" }, "encrypted_ta": { "key": "mLBjodcE4j36y64nC/nEs694P3XrLAOokjisXIGfs0H7lOEmT5FtaNDYEMcg9RnE ftlJGHO7N0lgcNcjoXBmeuY9VI8xzrsZM9gzH6VBKtVONSx0aw5IAFkNcyPZwDdZ MLwhvrzPJ9Fg+bZtrCoJz18PUz+5aNl/dj8+NM85LCXXcBlZF74btJer1Mw6ffzT /grPiEQTeJ1nEm9F3tyRsvcTInsnPJ3dEXv7sJXMrhRKAeZsqKzGX4eiZ3rEY+FQ 6nXULC8cAj5XTKpQ/EkZ/iGgS0zcXR7KUJv3wFEmtBtPD/+ze08NILLmxM8olQFj //Lq0gGtq8vPC8r0oOfmbQ==", "iv": "4F5472504973426F726E496E32303135", "alg": "AESCBC", "ciphertadata": "......0x/5KGCXWfg1Vrjm7zPVZqtYZ2EovBow+7EmfOJ1tbk......=", "cipherpdata": "0x/5KGCXWfg1Vrjm7zPVZqtYZ2EovBow+7EmfOJ1tbk=" } } } A.2.1.2. Sample InstallTAResponse A sample to-be-signed response of InstallTA looks as follows. { "InstallTATBSResponse": { "ver": "1.0", "status": "pass", "rid": "24BEB059-0AED-42A6-A381-817DFB7A1207", "tid": "4F454A7F-002D-4157-884E-B0DD1A06A8AE", "content": { "did": "MTZENTE5Qzc0Qzk0NkUxMzYxNzk0NjY4NTc3OTY4NTI=", "dsi": { "tfwdata": { Pei, et al. Expires April 26, 2019 [Page 100] Internet-Draft OTrP October 2018 "tbs": "ezRGNDU0QTdGLTAwMkQtNDE1Ny04ODRFLUIwREQxQTA2QThBRX0=" "cert": "ZXhhbXBsZSBGVyBjZXJ0aWZpY2F0ZQ==", "sigalg": "UlMyNTY=", "sig": "c2FtcGxlIEZXIHNpZ25hdHVyZQ==" }, "tee": { "name": "Primary TEE", "ver": "1.0", "cert": "c2FtcGxlIFRFRSBjZXJ0aWZpY2F0ZQ==", "cacert": [ "c2FtcGxlIENBIGNlcnRpZmljYXRlIDE=", "c2FtcGxlIENBIGNlcnRpZmljYXRlIDI=" ], "sdlist": { "cnt": "1", "sd": [ { "name": "com.acmebank.sdname1", "spid": "com.acmebank.spid1", "talist": [ { "taid": "com.acmebank.taid.banking", "taname": "Acme secure banking app" }, { "taid": "acom.acmebank.taid.loyalty.rewards", "taname": "Acme loyalty rewards app" } ] } ] }, "teeaiklist": [ { "spaik": "c2FtcGxlIEFTTjEgZW5jb2RlZCBQS0NTMSBwdWJsaWNrZXk=", "spaiktype": "RSA" "spid": "acmebank.com" } ] } } } } } Pei, et al. Expires April 26, 2019 [Page 101] Internet-Draft OTrP October 2018 A.2.2. Sample UpdateTA A.2.2.1. Sample UpdateTARequest { "UpdateTATBSRequest": { "ver": "1.0", "rid": "req-2", "tid": "tran-01", "tee": "SecuriTEE", "nextdsi": " false", "dsihash": "gwjul_9MZks3pqUSN1-eL1aViwGXNAxk0AIKW79dn4U", "content": { "tamid": "TAM1.acme.com", "spid": "bank.com", "sdname": "sd.bank.com", "taid": "sd.bank.com.ta" }, "encrypted_ta": { "key": " XzmAn_RDVk3IozMwNWhiB6fmZlIs1YUvMKlQAv_UDoZ1fvGGsRGo9bT0A440aYMgLt GilKypoJjCgijdaHgamaJgRSc4Je2otpnEEagsahvDNoarMCC5nGQdkRxW7Vo2NKgL A892HGeHkJVshYm1cUlFQ-BhiJ4NAykFwlqC_oc", "iv": "AxY8DCtDaGlsbGljb3RoZQ", "alg": "AESCBC", "ciphernewtadata": "KHqOxGn7ib1F_14PG4_UX9DBjOcWkiAZhVE-U- 67NsKryHGokeWr2spRWfdU2KWaaNncHoYGwEtbCH7XyNbOFh28nzwUmstep4nHWbAl XZYTNkENcABPpuw_G3I3HADo" } } } { "UpdateTARequest": { "payload" : " eyJVcGRhdGVUQVRCU1JlcXVlc3QiOnsidmVyIjoiMS4wIiwicmlkIjoicmVxLTIiLCJ0 aWQiOiJ0cmFuLTAxIiwidGVlIjoiU2VjdXJpVEVFIiwibmV4dGRzaSI6ImZhbHNlIiwi ZHNpaGFzaCI6Imd3anVsXzlNWmtzM3BxVVNOMS1lTDFhVml3R1hOQXhrMEFJS1c3OWRu NFUiLCJjb250ZW50Ijp7InByb3RlY3RlZCI6ImV5SmxibU1pT2lKQk1USTRRMEpETFVo VE1qVTJJbjAiLCJyZWNpcGllbnRzIjpbeyJoZWFkZXIiOnsiYWxnIjoiUlNBMV81In0s ImVuY3J5cHRlZF9rZXkiOiJYem1Bbl9SRFZrM0lvek13TldoaUI2Zm1abElzMVlVdk1L bFFBdl9VRG9aMWZ2R0dzUkdvOWJUMEE0NDBhWU1nTHRHaWxLeXBvSmpDZ2lqZGFIZ2Ft YUpnUlNjNEplMm90cG5FRWFnc2FodkROb2FyTUNDNW5HUWRrUnhXN1ZvMk5LZ0xBODky SEdlSGtKVnNoWW0xY1VsRlEtQmhpSjROQXlrRndscUNfb2MifV0sIml2IjoiQXhZOERD dERhR2xzYkdsamIzUm9aUSIsImNpcGhlcnRleHQiOiJIYTcwVXRZVEtWQmtXRFJuMi0w Pei, et al. Expires April 26, 2019 [Page 102] Internet-Draft OTrP October 2018 SF9IdkZtazl5SGtoVV91bk1OLWc1T3BqLWF1NGFUb2lxWklMYzVzYTdENnZZSjF6eW04 QW1JOEJIVXFqc2l5Z0tOcC1HdURJUjFzRXc0a2NhMVQ5ZENuU0RydHhSUFhESVdrZmt3 azZlR1NQWiIsInRhZyI6Im9UN01UTE41eWtBTFBoTDR0aUh6T1pPTGVFeU9xZ0NWaEM5 MXpkcldMU0UifSwiZW5jcnlwdGVkX3RhIjp7ImtleSI6Ilh6bUFuX1JEVmszSW96TXdO V2hpQjZmbVpsSXMxWVV2TUtsUUF2X1VEb1oxZnZHR3NSR285YlQwQTQ0MGFZTWdMdEdp bEt5cG9KakNnaWpkYUhnYW1hSmdSU2M0SmUyb3RwbkVFYWdzYWh2RE5vYXJNQ0M1bkdR ZGtSeFc3Vm8yTktnTEE4OTJIR2VIa0pWc2hZbTFjVWxGUS1CaGlKNE5BeWtGd2xxQ19v YyIsIml2IjoiQXhZOERDdERhR2xzYkdsamIzUm9aUSIsImFsZyI6IkFFU0NCQyIsImNp cGhlcm5ld3RhZGF0YSI6IktIcU94R243aWIxRl8xNFBHNF9VWDlEQmpPY1draUFaaFZF LVUtNjdOc0tyeUhHb2tlV3Iyc3BSV2ZkVTJLV2FhTm5jSG9ZR3dFdGJDSDdYeU5iT0Zo MjhuendVbXN0ZXA0bkhXYkFsWFpZVE5rRU5jQUJQcHV3X0czSTNIQURvIn19fQ", "protected": " eyJhbGciOiJSUzI1NiJ9", "header": { "kid":"e9bc097a-ce51-4036-9562-d2ade882db0d", "signer":" MIIC3zCCAkigAwIBAgIJAJf2fFkE1BYOMA0GCSqGSIb3DQEBBQUAMFoxCzAJBgNVBA YTAlVTMRMwEQYDVQQIDApDYWxpZm9ybmlhMRMwEQYDVQQHDApDYWxpZm9ybmlhMSEw HwYDVQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGQwHhcNMTUwNzAyMDkwMTE4Wh cNMjAwNjMwMDkwMTE4WjBaMQswCQYDVQQGEwJVUzETMBEGA1UECAwKQ2FsaWZvcm5p YTETMBEGA1UEBwwKQ2FsaWZvcm5pYTEhMB8GA1UECgwYSW50ZXJuZXQgV2lkZ2l0cy BQdHkgTHRkMIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC8ZtxM1bYickpgSVG- meHInI3f_chlMBdL8l7daOEztSs_a6GLqmvSu- AoDpTsfEd4EazdMBp5fmgLRGdCYMcI6bgpO94h5CCnlj8xFKPq7qGixdwGUA6b_ZI3 c4cZ8eu73VMNrrn_z3WTZlExlpT9XVj- ivhfJ4a6T20EtMM5qwIDAQABo4GsMIGpMHQGA1UdIwRtMGuhXqRcMFoxCzAJBgNVBA YTAlVTMRMwEQYDVQQIDApDYWxpZm9ybmlhMRMwEQYDVQQHDApDYWxpZm9ybmlhMSEw HwYDVQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGSCCQCX9nxZBNQWDjAJBgNVHR MEAjAAMA4GA1UdDwEB_wQEAwIGwDAWBgNVHSUBAf8EDDAKBggrBgEFBQcDAzANBgkq hkiG9w0BAQUFAAOBgQAGkz9QpoxghZUWT4ivem4cIckfxzTBBiPHCjrrjB2X8Ktn8G SZ1MdyIZV8fwdEmD90IvtMHgtzK- 9wo6Aibj_rVIpxGb7trP82uzc2X8VwYnQbuqQyzofQvcwZHLYplvi95pZ5fVrJvnYA UBFyfrdT5GjqL1nqH3a_Y3QPscuCjg" }, "signature":"inB1K6G3EAhF- FbID83UI25R5Ao8MI4qfrbrmf0UQhjM3O7_g3l6XxN_JkHrGQaZr- myOkGPVM8BzbUZW5GqxNZwFXwMeaoCjDKc4Apv4WZkD1qKJxkg1k5jaUCfJz1Jmw_XtX 6MHhrLh9ov03S9PtuT1VAQ0FVUB3qFIvjSnNU" } } A.2.2.2. Sample UpdateTAResponse Pei, et al. Expires April 26, 2019 [Page 103] Internet-Draft OTrP October 2018 { "UpdateTATBSResponse": { "ver": "1.0", "status": "pass", "rid": "req-2", "tid": "tran-01", "content": { "did": "zAHkb0-SQh9U_OT8mR5dB-tygcqpUJ9_x07pIiw8WoM" } } } Pei, et al. Expires April 26, 2019 [Page 104] Internet-Draft OTrP October 2018 { "UpdateTAResponse":{ "payload":" eyJVcGRhdGVUQVRCU1Jlc3BvbnNlIjp7InZlciI6IjEuMCIsInN0YXR1cyI6InBhc3Mi LCJyaWQiOiJyZXEtMiIsInRpZCI6InRyYW4tMDEiLCJjb250ZW50Ijp7InByb3RlY3Rl ZCI6ImV5SmxibU1pT2lKQk1USTRRMEpETFVoVE1qVTJJbjAiLCJyZWNpcGllbnRzIjpb eyJoZWFkZXIiOnsiYWxnIjoiUlNBMV81In0sImVuY3J5cHRlZF9rZXkiOiJFaGUxLUJB UUdJLTNEMFNHdXFGY01MZDJtd0gxQm1uRndYQWx1M1FxUFVXZ1RRVm55SUowNFc2MnBK YWVSREFkeTU0R0FSVjBrVzQ0RGw0MkdUUlhqbE1EZ3BYdXdFLWloc1JVV0tNNldCZ2N3 VXVGQTRUR3gwU0I1NTZCdl92dnBNaFdfMXh2c2FHdFBaQmwxTnZjbXNibzBhY3FobXlu bzBDTmF5SVAtX1UifV0sIml2IjoiQXhZOERDdERhR2xzYkdsamIzUm9aUSIsImNpcGhl cnRleHQiOiJwc2o2dGtyaGJXM0lmVElMeE9GMU5HdFUtcTFmeVBidV9KWk9jbklycWIw eTNPOHN6OTItaWpWR1ZyRW5WbG1sY1FYeWFNZTNyX1JGdEkwV3B4UmRodyIsInRhZyI6 Ik0zb2dNNk11MVJYMUMybEZvaG5rTkN5b25qNjd2TDNqd2RrZXhFdUlpaTgifX19", "protected":"eyJhbGciOiJSUzI1NiJ9", "header": { "kid":"e9bc097a-ce51-4036-9562-d2ade882db0d", "signer":" MIIC3zCCAkigAwIBAgIJAJf2fFkE1BYOMA0GCSqGSIb3DQEBBQUAMFoxCzAJBgNVBA YTAlVTMRMwEQYDVQQIDApDYWxpZm9ybmlhMRMwEQYDVQQHDApDYWxpZm9ybmlhMSEw HwYDVQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGQwHhcNMTUwNzAyMDkwMTE4Wh cNMjAwNjMwMDkwMTE4WjBaMQswCQYDVQQGEwJVUzETMBEGA1UECAwKQ2FsaWZvcm5p YTETMBEGA1UEBwwKQ2FsaWZvcm5pYTEhMB8GA1UECgwYSW50ZXJuZXQgV2lkZ2l0cy BQdHkgTHRkMIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC8ZtxM1bYickpgSVG- meHInI3f_chlMBdL8l7daOEztSs_a6GLqmvSu- AoDpTsfEd4EazdMBp5fmgLRGdCYMcI6bgpO94h5CCnlj8xFKPq7qGixdwGUA6b_ZI3 c4cZ8eu73VMNrrn_z3WTZlExlpT9XVj- ivhfJ4a6T20EtMM5qwIDAQABo4GsMIGpMHQGA1UdIwRtMGuhXqRcMFoxCzAJBgNVBA YTAlVTMRMwEQYDVQQIDApDYWxpZm9ybmlhMRMwEQYDVQQHDApDYWxpZm9ybmlhMSEw HwYDVQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGSCCQCX9nxZBNQWDjAJBgNVHR MEAjAAMA4GA1UdDwEB_wQEAwIGwDAWBgNVHSUBAf8EDDAKBggrBgEFBQcDAzANBgkq hkiG9w0BAQUFAAOBgQAGkz9QpoxghZUWT4ivem4cIckfxzTBBiPHCjrrjB2X8Ktn8G SZ1MdyIZV8fwdEmD90IvtMHgtzK- 9wo6Aibj_rVIpxGb7trP82uzc2X8VwYnQbuqQyzofQvcwZHLYplvi95pZ5fVrJvnYA UBFyfrdT5GjqL1nqH3a_Y3QPscuCjg" }, "signature":" Twajmt_BBLIMcNrDsjqr8lI7O7lEQxXZNhlUOtFkOMMqf37wOPKtp_99LoS82CVmdpCo PLaws8zzh-SNIQ42- 9GYO8_9BaEGCiCwyl8YgWP9fWNfNv2gR2fl2DK4uknkYu1EMBW4YfP81n_pGpb4Gm- nMk14grVZygwAPej3ZZk" } } Pei, et al. Expires April 26, 2019 [Page 105] Internet-Draft OTrP October 2018 A.2.3. Sample DeleteTA A.2.3.1. Sample DeleteTARequest { "DeleteTATBSRequest": { "ver": "1.0", "rid": "req-2", "tid": "tran-01", "tee": "SecuriTEE", "nextdsi": "false", "dsihash": "gwjul_9MZks3pqUSN1-eL1aViwGXNAxk0AIKW79dn4U", "content": { "tamid": "TAM1.acme.com", "sdname": "sd.bank.com", "taid": "sd.bank.com.ta" } } } Pei, et al. Expires April 26, 2019 [Page 106] Internet-Draft OTrP October 2018 { "DeleteTARequest": { "payload": " eyJEZWxldGVUQVRCU1JlcXVlc3QiOnsidmVyIjoiMS4wIiwicmlkIjoicmVxLTIiLCJ0 aWQiOiJ0cmFuLTAxIiwidGVlIjoiU2VjdXJpVEVFIiwibmV4dGRzaSI6ImZhbHNlIiwi ZHNpaGFzaCI6Imd3anVsXzlNWmtzM3BxVVNOMS1lTDFhVml3R1hOQXhrMEFJS1c3OWRu NFUiLCJjb250ZW50Ijp7InByb3RlY3RlZCI6eyJlbmMiOiJBMTI4Q0JDLUhTMjU2In0s InJlY2lwaWVudHMiOlt7ImhlYWRlciI6eyJhbGciOiJSU0ExXzUifSwiZW5jcnlwdGVk X2tleSI6ImtyaGs0d2dpY0RlX3d0VXQyTW4tSUJsdUtvX0JkeXpNY2p1cVlBenBPYnRS TG9MZzQ0QkFLN2tRVWE1YTg0TEVJRGEzaHNtWDIxdldNZFJLczN4MTJsOUh5VFdfLUNS WmZtcUx2bEh1LV9MSVdvc1ZyRTZVMlJqUnRndllVOWliUkVLczkzRDRHWm4xVHFuZG9n d0tXRF9jdG1nWG1sbzZZVXpCWDZhR1dZMCJ9XSwiaXYiOiJBeFk4REN0RGFHbHNiR2xq YjNSb1pRIiwiY2lwaGVydGV4dCI6IkhhNzBVdFlUS1ZCa1dEUm4yLTBIX1BGa19yQnpQ dGJHdzhSNktlMXotdklNeFBSY0Nxa1puZmwyTjRjUTZPSTZCSHZJUUFoM2Jic0l0dHlR bXhDTE5Nbm8wejBrYm9TdkIyVXlxWExpeGVZIiwidGFnIjoidEtUbFRLdlR2LTRtVVlG Y1dYWnZMMVlhQnRGNloxVlNxOTMzVmI2UEpmcyJ9fX0", "protected" : "eyJhbGciOiJSUzI1NiJ9", "header": { "kid":"e9bc097a-ce51-4036-9562-d2ade882db0d", "signer":" MIIC3zCCAkigAwIBAgIJAJf2fFkE1BYOMA0GCSqGSIb3DQEBBQUAMFoxCzAJBgNVBA YTAlVTMRMwEQYDVQQIDApDYWxpZm9ybmlhMRMwEQYDVQQHDApDYWxpZm9ybmlhMSEw HwYDVQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGQwHhcNMTUwNzAyMDkwMTE4Wh cNMjAwNjMwMDkwMTE4WjBaMQswCQYDVQQGEwJVUzETMBEGA1UECAwKQ2FsaWZvcm5p YTETMBEGA1UEBwwKQ2FsaWZvcm5pYTEhMB8GA1UECgwYSW50ZXJuZXQgV2lkZ2l0cy BQdHkgTHRkMIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC8ZtxM1bYickpgSVG- meHInI3f_chlMBdL8l7daOEztSs_a6GLqmvSu- AoDpTsfEd4EazdMBp5fmgLRGdCYMcI6bgpO94h5CCnlj8xFKPq7qGixdwGUA6b_ZI3 c4cZ8eu73VMNrrn_z3WTZlExlpT9XVj- ivhfJ4a6T20EtMM5qwIDAQABo4GsMIGpMHQGA1UdIwRtMGuhXqRcMFoxCzAJBgNVBA YTAlVTMRMwEQYDVQQIDApDYWxpZm9ybmlhMRMwEQYDVQQHDApDYWxpZm9ybmlhMSEw HwYDVQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGSCCQCX9nxZBNQWDjAJBgNVHR MEAjAAMA4GA1UdDwEB_wQEAwIGwDAWBgNVHSUBAf8EDDAKBggrBgEFBQcDAzANBgkq hkiG9w0BAQUFAAOBgQAGkz9QpoxghZUWT4ivem4cIckfxzTBBiPHCjrrjB2X8Ktn8G SZ1MdyIZV8fwdEmD90IvtMHgtzK- 9wo6Aibj_rVIpxGb7trP82uzc2X8VwYnQbuqQyzofQvcwZHLYplvi95pZ5fVrJvnYA UBFyfrdT5GjqL1nqH3a_Y3QPscuCjg" }, "signature" : " BZS0_Ab6pqvGNXe5lqT4Sc3jakyWQeiK9KlVSnimwWnjCCyMtyB9bwvlbILZba3IJiFe _3F9bIQpSytGS0f2TQrPTKC7pSjwDw-3kH7HkHcPPJd- PpMMfQvRx7AIV8vBqO9MijIC62iN0V2se5z2v8VFjGSoRGgq225w7FvrnWE" } } Pei, et al. Expires April 26, 2019 [Page 107] Internet-Draft OTrP October 2018 A.2.3.2. Sample DeleteTAResponse { "DeleteTATBSResponse": { "ver": "1.0", "status": "pass", "rid": "req-2", "tid": "tran-01", "content": { "did": "zAHkb0-SQh9U_OT8mR5dB-tygcqpUJ9_x07pIiw8WoM" } } } Pei, et al. Expires April 26, 2019 [Page 108] Internet-Draft OTrP October 2018 { "DeleteTAResponse":{ "payload":" ew0KCSJEZWxldGVUQVRCU1Jlc3BvbnNlIjogew0KCQkidmVyIjogIjEuMCIsDQoJCSJz dGF0dXMiOiAicGFzcyIsDQoJCSJyaWQiOiAicmVxLTIiLA0KCQkidGlkIjogInRyYW4t MDEiLA0KCQkiY29udGVudCI6IHsNCgkJCSJwcm90ZWN0ZWQiOnsiZW5jIjoiQTEyOENC Qy1IUzI1NiJ9LA0KCQkJInJlY2lwaWVudHMiOlsNCgkJCQl7DQoJCQkJCSJoZWFkZXIi OnsiYWxnIjoiUlNBMV81In0sDQoJCQkJCSJlbmNyeXB0ZWRfa2V5IjoiTXdtU1ZHaWU2 eHpfQmxTaFlmTFRKRHhKT3oyNWhvYy1HZ2NEM2o5OWFyM2E4X2lYY182ZE44bFRTb1dD X19wZEFhaEMyWk5SakdIcTBCZ2JDYTRKalk0eXRkMVBVWDB6M1psbXl1YnRXM291eEpY el9PMzg1WGM4S3hySndjbElyZGx2WUY2OVZmeERLQkVzUHJCdzlVenVIa1VmSU4xWlFU bWZ0QmVaSlJnIg0KCQkJCX0NCgkJCV0sDQoJCQkiaXYiOiJBeFk4REN0RGFHbHNiR2xq YjNSb1pRIiwNCgkJCSJjaXBoZXJ0ZXh0IjoiamhQTlV5ZkFTel9rVV9GbEM2LUtCME01 WDBHNE5MbHc0LWt0bERyajZTWlUteUp6eUFUbC1oY0ZBWWMwLXJMVEF4cF93N1d1WER0 Y3N3SzJSSzRjcWciLA0KCQkJInRhZyI6IlBBeGo5N25oT29qVTNIREhxSll4MGZMNWpt b0xkTlJkTHRTAMIzUTdrYXciDQoJCX0NCgl9DQp9", "protected": "eyJhbGciOiJSUzI1NiJ9", "header": { "kid":"e9bc097a-ce51-4036-9562-d2ade882db0d", "signer":" MIIC3zCCAkigAwIBAgIJAJf2fFkE1BYOMA0GCSqGSIb3DQEBBQUAMFoxCzAJ BgNVBAYTAlVTMRMwEQYDVQQIDApDYWxpZm9ybmlhMRMwEQYDVQQHDApDYWxp Zm9ybmlhMSEwHwYDVQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGQwHhcN MTUwNzAyMDkwMTE4WhcNMjAwNjMwMDkwMTE4WjBaMQswCQYDVQQGEwJVUzET MBEGA1UECAwKQ2FsaWZvcm5pYTETMBEGA1UEBwwKQ2FsaWZvcm5pYTEhMB8G A1UECgwYSW50ZXJuZXQgV2lkZ2l0cyBQdHkgTHRkMIGfMA0GCSqGSIb3DQEB AQUAA4GNADCBiQKBgQC8ZtxM1bYickpgSVG- meHInI3f_chlMBdL8l7daOEztSs_a6GLqmvSu- AoDpTsfEd4EazdMBp5fmgLRGdCYMcI6bgpO94h5CCnlj8xFKPq7qGixdwGUA 6b_ZI3c4cZ8eu73VMNrrn_z3WTZlExlpT9XVj- ivhfJ4a6T20EtMM5qwIDAQABo4GsMIGpMHQGA1UdIwRtMGuhXqRcMFoxCzAJ BgNVBAYTAlVTMRMwEQYDVQQIDApDYWxpZm9ybmlhMRMwEQYDVQQHDApDYWxp Zm9ybmlhMSEwHwYDVQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGSCCQCX 9nxZBNQWDjAJBgNVHRMEAjAAMA4GA1UdDwEB_wQEAwIGwDAWBgNVHSUBAf8E DDAKBggrBgEFBQcDAzANBgkqhkiG9w0BAQUFAAOBgQAGkz9QpoxghZUWT4iv em4cIckfxzTBBiPHCjrrjB2X8Ktn8GSZ1MdyIZV8fwdEmD90IvtMHgtzK- 9wo6Aibj_rVIpxGb7trP82uzc2X8VwYnQbuqQyzofQvcwZHLYplvi95pZ5fV rJvnYAUBFyfrdT5GjqL1nqH3a_Y3QPscuCjg" }, "signature":" DfoBOetNelKsnAe_m4Z9K5UbihgWNYZsp5jVybiI05sOagDzv6R4do9npaAlAvpNK8HJ CxD6D22J8GDUExlIhSR1aDuDCQm6QzmjdkFdxAz5TRYl6zpPCZqgSToN_g1TZxqxEv6V Ob5fies4g6MHvCH-Il_-KbHq5YpwGxEEFdg" } } Pei, et al. Expires April 26, 2019 [Page 109] Internet-Draft OTrP October 2018 A.3. Example OTrP Broker Option The most popular TEE devices today are Android powered devices. In an Android device, an OTrP Broker can be a bound service with a service registration ID that a Client Application can use. This option allows a Client Application not to depend on any OTrP Broker SDK or provider. An OTrP Broker is responsible to detect and work with more than one TEE if a device has more than one. In this version, there is only one active TEE such that an OTrP Broker only needs to handle the active TEE. Appendix B. Contributors - Brian Witten Symantec brian_witten@symantec.com - Tyler Kim Solacia tylerkim@iotrust.kr Authors' Addresses Mingliang Pei Symantec 350 Ellis St Mountain View, CA 94043 USA Email: mingliang_pei@symantec.com Andrew Atyeo Intercede St. Mary's Road, Lutterworth Leicestershire, LE17 4PS Great Britain Email: andrew.atyeo@intercede.com Pei, et al. Expires April 26, 2019 [Page 110] Internet-Draft OTrP October 2018 Nick Cook ARM Ltd. 110 Fulbourn Rd Cambridge, CB1 9NJ Great Britain Email: nicholas.cook@arm.com Minho Yoo IoTrust Suite 501, Gasanbusiness Center,165, Gasan digital1-ro Seoul 08503 Korea Email: minho.yoo@iotrust.kr Hannes Tschofenig ARM Ltd. 110 Fulbourn Rd Cambridge, CB1 9NJ Great Britain Email: hannes.tschofenig@arm.com Pei, et al. Expires April 26, 2019 [Page 111]