Secured Frames for MMS Ranging in IEEE P802.15 Working Group
Explore considerations for securing MMS ranging in wireless personal area networks (WPANs) within the IEEE P802.15 Working Group. The document discusses security measures for ensuring high integrity ranging, improved accuracy, and reliability in MMS frames. It also covers interference mitigation techniques, backward compatibility, enhanced link budget, and reduced power consumption. Discover mechanisms for securing frames used in MMS ranging, alongside enhancements in discovery mechanisms, low-latency streaming, and support for various protocols.
Download Presentation
Please find below an Image/Link to download the presentation.
The content on the website is provided AS IS for your information and personal use only. It may not be sold, licensed, or shared on other websites without obtaining consent from the author. If you encounter any issues during the download, it is possible that the publisher has removed the file from their server.
You are allowed to download the files provided on this website for personal or commercial use, subject to the condition that they are used lawfully. All files are the property of their respective owners.
The content on the website is provided AS IS for your information and personal use only. It may not be sold, licensed, or shared on other websites without obtaining consent from the author.
E N D
Presentation Transcript
May 2023 Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) doc.: < 15-23-0216-00-04ab > Submission Title: Secured frames for MMS ranging Date Submitted: May, 2023 Source: Rojan Chitrakar, Lei Huang, Kuan Wu, Stephen McCann, David Xun Yang (Huawei Technologies) Email: rojan.chitrakar@huawei.com Abstract: Considerations for security for MMS ranging. Purpose: Considerations for security for MMS ranging. Notice: This document has been prepared to assist the IEEE P802.15. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.15. Submission Slide 1 Rojan Chitrakar, et al
May 2023 doc.: < 15-23-0216-00-04ab > PAR Objective Proposed Solution (how addressed) Safeguards so that the high throughput data use cases will not cause significant disruption to low duty-cycle ranging use cases Interference mitigation techniques to support higher density and higher traffic use cases Other coexistence improvement Backward compatibility with enhanced ranging capable devices (ERDEVs) Improved link budget and/or reduced air-time Additional channels and operating frequencies Improvements to accuracy / precision / reliability and interoperability for high-integrity ranging Reduced complexity and power consumption Hybrid operation with narrowband signaling to assist UWB Mechanism to provide security for frames used for MMS ranging (NBA or UWB) Mechanism to provide security for frames used for MMS ranging (NBA or UWB) Enhanced native discovery and connection setup mechanisms Sensing capabilities to support presence detection and environment mapping Low-power low-latency streaming Higher data-rate streaming allowing at least 50 Mbit/s of throughput Support for peer-to-peer, peer-to-multi-peer, and station-to- infrastructure protocols Infrastructure synchronization mechanisms Submission Slide 2 Rojan Chitrakar, et al
May 2023 doc.: < 15-23-0216-00-04ab > Background: Compressed PSDU [1] introduces NBA-MMS-UWB Compressed PSDU: Keeping NB packets shorter than 1ms; NB O-QPSK 250k has limited PSDU capacity (~25 bytes/ms) 1. Compressed PSDU specific to NBA-MMS-UWB control frames: 1-octet message ID (0x00=Poll, 0x01=Response, 0x02=Report, ) 2-octet session identifier/address ID specific data (variable length) 2-octet CRC16 2. Secure compressed PSDU (Example: Report with Secured timestamp): 1-octet message ID (0xtbd) 2-octet session identifier/address 4-octet timestamp(s) (Secured) 8-octet cryptographic protection (MAC) Redundancy between ENC-MIC-64 and CRC16 can be exploited to reduce PSDU size [1] 15-22/0604r0, NBA-MMS-UWB Compressed PSDU, Alexander Krebs Submission Slide 3 Rojan Chitrakar, et al
May 2023 doc.: < 15-23-0216-00-04ab > Background: Compressed Header IE [2] Using header IE-only packets for broadcast traffic in NBA-MMS UWB Enabling compressed PSDU design principles for header IE design Stripping IE length field for message compression Maintaining the frame control (FC) field in 15.4 for managing the compressed header IE Octets: 1/2 2 1 Variable 2 FC Address Header IE message ID (128~255) Data Content CRC Proposed 15.4ab compressed PSDU (controlled via FC) ID ADR DATA CRC ID DATA LEN FC ADR CRC Proposed 15.4ab Header IE optimization Header IE 128-255 MHR MFR [2] 15-22/608r1, Header IE Extension, Alexander Krebs Submission Slide 4 Rojan Chitrakar, et al
May 2023 Background: Authenticated encryption with associated data (AEAD) Security Operation in 802.15.4-2020 AEAD encryption and authentication transformation (CCM* using AES-128) : 3 levels for Authentication and 3 levels for encryption are provided. The inputs are as follows: Key Nonce a data (AddAuthData: data to be authenticated) m data (PlaintextData: data to be encrypted) doc.: < 15-23-0216-00-04ab > The output is c data (Ciphertext + MIC) The Private Payload field of the original unsecured frame shall be replaced by the right-concatenation of that field and the c field if data confidentiality is not provided and shall be replaced by the c field otherwise Submission Slide 5 Rojan Chitrakar, et al
May 2023 Background: Authenticated encryption with associated data (AEAD) Security Operation in 802.15.4-2020 AEAD transformation and inverse transformation: The Nonce is constructed from the content of the MHR: doc.: < 15-23-0216-00-04ab > In TSCH mode, Absolute Slot Number (ASN) is used in Nonce instead of frame counter. Frame Counter is not present in the MHR. Submission Slide 6 Rojan Chitrakar, et al
May 2023 doc.: < 15-23-0216-00-04ab > Motivation: MMS ranging representative flow: ... ... Initialization and Setup Measurement Cycles Time offset ADV- POLL POLL RPRT Initiator SOR UWB Ranging ADV- RESP RESP RPRT Responder Control Phase Ranging Phase Report Phase May carry sensitive information related to the ranging session (e.g., Time offset, block structure parameters, RSF code index etc.) . Measurement Cycle May carry sensitive information related to the ranging measurement (e.g. RTT, AOA etc.) At minimum 802.15.4ab should be able to Authenticate frames. If supported, encryption of sensitive information in the frames should also be supported. Submission Slide 7 Rojan Chitrakar, et al
May 2023 doc.: < 15-23-0216-00-04ab > Discussion As explained earlier, 802.15.4-2020 already provides comprehensive AEAD security operation. We would like to reuse the existing AEAD operation for 802.15.4ab as much as possible for both NB and non-NB frames. Annex B mandates that within the scope of any encryption key, the nonce value shall be unique. Two formats of nonce are provided in 802.15.4-2020 : A key question is how to construct the variable field of the Nonce (Frame Counter or ASN), especially for compressed frames that do not carry a frame counter? Submission Slide 8 Rojan Chitrakar, et al
May 2023 doc.: < 15-23-0216-00-04ab > Proposal 1 Different frame format and nonce construction methods are used for secured frames in the Initialization and Setup phase and frames in Measurement Cycles. Outside Block Structure (Initialization and Setup) Inside Block Structure (Measurement Cycles) ... ... Block 0 Block 1 Block 2 Round 0 Round 1 Round n Round 0 Round 1 Round n Round 0 Round 1 Round n ... ... ... ... A secured frame carries the frame counter to construct the Nonce. Slot 0 Slot 1 Slot m ... The indices of the Block, Round, Slot in which a secured frame is transmitted or received, are used as a frame counter to construct the Nonce. Time offset ADV- POLL Initiator POLL RPRT SOR UWB Ranging ADV- RESP Responder RESP RPRT Carry Packet Number (PN) used as frame counter for Nonce construction. Do not carry Packet Number (PN) Submission Slide 9 Rojan Chitrakar, et al
May 2023 doc.: < 15-23-0216-00-04ab > Proposal 1 A 4 octets Packet Number (PN) is carried in a secured frame that is transmitted during the Initialization and Setup phase (e.g., SOR, ADV-RESP). The Packet Number (PN) is used as frame counter for Nonce construction. One bit (e.g., the MSB of the ID field) indicates whether security is enabled or not. The MIC obtained from the AEAD security operation replaces the CRC. Size of the MIC field depends on the negotiated security level. Example: Secured SOR Bits: 0-6 4/8 0 or 4 7 Octets: 2 variable Nonce Security Enabled = 1 Secured Payload Octets: 8 4 1 MIC PN Address ID Frame Counter (PN) Nonce Security Level Source Address Submission Slide 10 Rojan Chitrakar, et al
May 2023 doc.: < 15-23-0216-00-04ab > Proposal 1 Frame Counter is not carried in a secured frame that is transmitted in a measurement cycle (e.g., RPRT). The indices of the Block, Round, Slot in which a secured frame is transmitted or received is used as a frame counter to construct the nonce. Example (if an encrypted RPRT is transmitted in slot m, round 1 of block 1): Time offset Block 0 Block 1 Block 2 Block 3 Round 0 Round 1 Round n Round 0 Round 1 Round n Round 0 Round 1 Round n Round 0 Round 1 Round n ... ... ... ... ... Slot 0 Slot 1 Slot m ... Nonce Encrypted RPRT Octets: 8 Bits: 0-7 8-23 24-39 4/8 7 Octets: 2 variable Bits: 0-6 Frame Counter (40 bits) Source Address Security Enabled = 1 Encrypted Payload Slot Index = m Round Index = 1 Block Index = 1 MIC Address ID Submission Slide 11 Rojan Chitrakar, et al
May 2023 doc.: < 15-23-0216-00-04ab > Proposal 2 Unified frame format and nonce construction method are used in the Initialization and Setup phase as well as in the Measurement Cycles. Assumption: Block structure (at least block and round) exists during the Initialization and Setup phase. ... Measurement Cycles Initialization and Setup Inside Block Structure Block 0 Block 10 Block 6 Block 11 Block 12 ... ... Round 0 Round 1 Round n Round 0 Round 1 Round n Round 0 Round 1 Round n Round 0 Round 1 Round n Round 0 Round 1 Round n ... ... ... ... ... ... Time offset ADV- POLL ADV- POLL POLL RPRT Initiator ... SOR UWB Ranging ADV- RESP RESP RPRT Responder Secured frames carry a short Packet Number (PN); the PN and round, block indices are used as frame counter to construct nonce Submission Slide 12 Rojan Chitrakar, et al
May 2023 doc.: < 15-23-0216-00-04ab > Proposal 2 Examples (if an encrypted RPRT is transmitted in round 1 of block 10): ... Measurement Cycles Initialization and Setup Inside Block Structure Block 0 Block 10 Block 6 Block 11 Block 12 ... ... Round 0 Round 1 Round n Round 0 Round 1 Round n Round 0 Round 1 Round n Round 0 Round 1 Round n Round 0 Round 1 Round n ... ... ... ... ... ... Nonce Octets: 8 Bits: 0-7 8-23 24-39 Frame Counter (40 bits) Source Address Block Index = 10 Round Index = 1 PN Encrypted SOR Bits: 0-6 Security Enabled Encrypted RPRT Bits: 0-6 4/8 0 or 1 7 Octets: 2 variable 4/8 0 or 1 7 Octets: 2 variable Security Enabled = 1 Encrypted Payload Encrypted Payload MIC PN Address ID MIC PN Address ID = 1 Submission Slide 13 Rojan Chitrakar, et al
May 2023 doc.: < 15-23-0216-00-04ab > Field selection for secured operation 802.15.4-2020 allows encryption of a selected field of the MAC payload field for the following: For all other frames, if encryption is enabled, the entire MAC payload field needs to be encrypted. For compressed frames, 802.15-4-2020 compliant selective encryption of the MAC payload field could be achieved by placing the private payload field at the end of the MAC payload field: Encrypted RPRT 4/8 7 Octets: 2 variable variable Bits: 0-6 Security Enabled = 1 Unencrypted Payload Encrypted Payload MIC Address ID Open Payload Slide 14 MAC Header Private Payload Submission Rojan Chitrakar, et al
May 2023 doc.: < 15-23-0216-00-04ab > Summary We discussed enabling security for the compressed frames. We proposed two methods to construct the nonce for the security operation: 1) Different frame formats and nonce construction methods are used for secured frames in the Initialization and Setup phase and in Measurement Cycles. 2) Unified frame format and nonce construction method are used for secured frames in the Initialization and Setup phase as well as in Measurement Cycles. Submission Slide 15 Rojan Chitrakar, et al
May 2023 doc.: < 15-23-0216-00-04ab > Annex - I Exceptions to Private Payload field and Open Payload field definitions: Submission Slide 16 Rojan Chitrakar, et al
