draft-ietf-detnet-security-00.txt | draft-ietf-detnet-security-01.txt | |||
---|---|---|---|---|
Internet Engineering Task Force T. Mizrahi | Internet Engineering Task Force T. Mizrahi | |||
Internet-Draft MARVELL | Internet-Draft MARVELL | |||
Intended status: Informational E. Grossman, Ed. | Intended status: Informational E. Grossman, Ed. | |||
Expires: April 2, 2018 DOLBY | Expires: May 3, 2018 DOLBY | |||
A. Hacker | A. Hacker | |||
MISTIQ | MISTIQ | |||
S. Das | S. Das | |||
Applied Communication Sciences | Applied Communication Sciences | |||
J. Dowdell | J. Dowdell | |||
Airbus Defence and Space | Airbus Defence and Space | |||
H. Austad | H. Austad | |||
Cisco Systems | Cisco Systems | |||
K. Stanton | K. Stanton | |||
INTEL | INTEL | |||
N. Finn | N. Finn | |||
HUAWEI | HUAWEI | |||
September 29, 2017 | October 30, 2017 | |||
Deterministic Networking (DetNet) Security Considerations | Deterministic Networking (DetNet) Security Considerations | |||
draft-ietf-detnet-security-00 | draft-ietf-detnet-security-01 | |||
Abstract | Abstract | |||
A deterministic network is one that can carry data flows for real- | A deterministic network is one that can carry data flows for real- | |||
time applications with extremely low data loss rates and bounded | time applications with extremely low data loss rates and bounded | |||
latency. Deterministic networks have been successfully deployed in | latency. Deterministic networks have been successfully deployed in | |||
real-time operational technology (OT) applications for some years | real-time operational technology (OT) applications for some years | |||
(for example [ARINC664P7]). However, such networks are typically | (for example [ARINC664P7]). However, such networks are typically | |||
isolated from external access, and thus the security threat from | isolated from external access, and thus the security threat from | |||
external attackers is low. IETF Deterministic Networking (DetNet) | external attackers is low. IETF Deterministic Networking (DetNet) | |||
skipping to change at page 2, line 20 ¶ | skipping to change at page 2, line 20 ¶ | |||
Internet-Drafts are working documents of the Internet Engineering | Internet-Drafts are working documents of the Internet Engineering | |||
Task Force (IETF). Note that other groups may also distribute | Task Force (IETF). Note that other groups may also distribute | |||
working documents as Internet-Drafts. The list of current Internet- | working documents as Internet-Drafts. The list of current Internet- | |||
Drafts is at https://datatracker.ietf.org/drafts/current/. | Drafts is at https://datatracker.ietf.org/drafts/current/. | |||
Internet-Drafts are draft documents valid for a maximum of six months | Internet-Drafts are draft documents valid for a maximum of six months | |||
and may be updated, replaced, or obsoleted by other documents at any | and may be updated, replaced, or obsoleted by other documents at any | |||
time. It is inappropriate to use Internet-Drafts as reference | time. It is inappropriate to use Internet-Drafts as reference | |||
material or to cite them other than as "work in progress." | material or to cite them other than as "work in progress." | |||
This Internet-Draft will expire on April 2, 2018. | This Internet-Draft will expire on May 3, 2018. | |||
Copyright Notice | Copyright Notice | |||
Copyright (c) 2017 IETF Trust and the persons identified as the | Copyright (c) 2017 IETF Trust and the persons identified as the | |||
document authors. All rights reserved. | document authors. All rights reserved. | |||
This document is subject to BCP 78 and the IETF Trust's Legal | This document is subject to BCP 78 and the IETF Trust's Legal | |||
Provisions Relating to IETF Documents | Provisions Relating to IETF Documents | |||
(https://trustee.ietf.org/license-info) in effect on the date of | (https://trustee.ietf.org/license-info) in effect on the date of | |||
publication of this document. Please review these documents | publication of this document. Please review these documents | |||
skipping to change at page 2, line 46 ¶ | skipping to change at page 2, line 46 ¶ | |||
Table of Contents | Table of Contents | |||
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4 | 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4 | |||
2. Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . 5 | 2. Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . 5 | |||
3. Security Threats . . . . . . . . . . . . . . . . . . . . . . 6 | 3. Security Threats . . . . . . . . . . . . . . . . . . . . . . 6 | |||
3.1. Threat Model . . . . . . . . . . . . . . . . . . . . . . 6 | 3.1. Threat Model . . . . . . . . . . . . . . . . . . . . . . 6 | |||
3.2. Threat Analysis . . . . . . . . . . . . . . . . . . . . . 7 | 3.2. Threat Analysis . . . . . . . . . . . . . . . . . . . . . 7 | |||
3.2.1. Delay . . . . . . . . . . . . . . . . . . . . . . . . 7 | 3.2.1. Delay . . . . . . . . . . . . . . . . . . . . . . . . 7 | |||
3.2.1.1. Delay Attack . . . . . . . . . . . . . . . . . . 7 | 3.2.1.1. Delay Attack . . . . . . . . . . . . . . . . . . 7 | |||
3.2.2. DetNet Flow Identification . . . . . . . . . . . . . 7 | 3.2.2. DetNet Flow Modification or Spoofing . . . . . . . . 7 | |||
3.2.2.1. DetNet Flow Modification or Spoofing . . . . . . 7 | ||||
3.2.3. Resource Segmentation or Slicing . . . . . . . . . . 7 | 3.2.3. Resource Segmentation or Slicing . . . . . . . . . . 7 | |||
3.2.3.1. Inter-segment Attack . . . . . . . . . . . . . . 7 | 3.2.3.1. Inter-segment Attack . . . . . . . . . . . . . . 7 | |||
3.2.4. Packet Replication and Elimination . . . . . . . . . 7 | 3.2.4. Packet Replication and Elimination . . . . . . . . . 8 | |||
3.2.4.1. Replication: Increased Attack Surface . . . . . . 8 | 3.2.4.1. Replication: Increased Attack Surface . . . . . . 8 | |||
3.2.4.2. Replication-related Header Manipulation . . . . . 8 | 3.2.4.2. Replication-related Header Manipulation . . . . . 8 | |||
3.2.5. Path Choice . . . . . . . . . . . . . . . . . . . . . 8 | 3.2.5. Path Choice . . . . . . . . . . . . . . . . . . . . . 8 | |||
3.2.5.1. Path Manipulation . . . . . . . . . . . . . . . . 8 | 3.2.5.1. Path Manipulation . . . . . . . . . . . . . . . . 8 | |||
3.2.5.2. Path Choice: Increased Attack Surface . . . . . . 8 | 3.2.5.2. Path Choice: Increased Attack Surface . . . . . . 9 | |||
3.2.6. Control Plane . . . . . . . . . . . . . . . . . . . . 9 | 3.2.6. Control Plane . . . . . . . . . . . . . . . . . . . . 9 | |||
3.2.6.1. Control or Signaling Packet Modification . . . . 9 | 3.2.6.1. Control or Signaling Packet Modification . . . . 9 | |||
3.2.6.2. Control or Signaling Packet Injection . . . . . . 9 | 3.2.6.2. Control or Signaling Packet Injection . . . . . . 9 | |||
3.2.7. Scheduling or Shaping . . . . . . . . . . . . . . . . 9 | 3.2.7. Scheduling or Shaping . . . . . . . . . . . . . . . . 9 | |||
3.2.7.1. Reconnaissance . . . . . . . . . . . . . . . . . 9 | 3.2.7.1. Reconnaissance . . . . . . . . . . . . . . . . . 9 | |||
3.2.8. Time Synchronization Mechanisms . . . . . . . . . . . 9 | 3.2.8. Time Synchronization Mechanisms . . . . . . . . . . . 9 | |||
3.3. Threat Summary . . . . . . . . . . . . . . . . . . . . . 9 | 3.3. Threat Summary . . . . . . . . . . . . . . . . . . . . . 9 | |||
4. Security Threat Impacts . . . . . . . . . . . . . . . . . . . 10 | 4. Security Threat Impacts . . . . . . . . . . . . . . . . . . . 10 | |||
4.1. Delay-Attacks . . . . . . . . . . . . . . . . . . . . . . 10 | 4.1. Delay-Attacks . . . . . . . . . . . . . . . . . . . . . . 13 | |||
4.1.1. Data Plane Delay Attacks . . . . . . . . . . . . . . 11 | 4.1.1. Data Plane Delay Attacks . . . . . . . . . . . . . . 13 | |||
4.1.2. Control Plane Delay Attacks . . . . . . . . . . . . . 11 | 4.1.2. Control Plane Delay Attacks . . . . . . . . . . . . . 13 | |||
4.2. Flow Identification and Spoofing . . . . . . . . . . . . 11 | 4.2. Flow Modification and Spoofing . . . . . . . . . . . . . 14 | |||
4.2.1. Flow identification . . . . . . . . . . . . . . . . . 11 | 4.2.1. Flow Modification . . . . . . . . . . . . . . . . . . 14 | |||
4.2.2. Spoofing . . . . . . . . . . . . . . . . . . . . . . 12 | 4.2.2. Spoofing . . . . . . . . . . . . . . . . . . . . . . 14 | |||
4.2.2.1. Dataplane Spoofing . . . . . . . . . . . . . . . 12 | 4.2.2.1. Dataplane Spoofing . . . . . . . . . . . . . . . 14 | |||
4.2.2.2. Control Plane Spoofing . . . . . . . . . . . . . 12 | 4.2.2.2. Control Plane Spoofing . . . . . . . . . . . . . 14 | |||
4.3. Segmentation attacks (injection) . . . . . . . . . . . . 12 | 4.3. Segmentation attacks (injection) . . . . . . . . . . . . 15 | |||
4.3.1. Data Plane Segmentation . . . . . . . . . . . . . . . 12 | 4.3.1. Data Plane Segmentation . . . . . . . . . . . . . . . 15 | |||
4.3.2. Control Plane segmentation . . . . . . . . . . . . . 13 | 4.3.2. Control Plane segmentation . . . . . . . . . . . . . 15 | |||
4.4. Replication and Elimination . . . . . . . . . . . . . . . 13 | 4.4. Replication and Elimination . . . . . . . . . . . . . . . 15 | |||
4.4.1. Increased Attack Surface . . . . . . . . . . . . . . 13 | 4.4.1. Increased Attack Surface . . . . . . . . . . . . . . 15 | |||
4.4.2. Header Manipulation at Elimination Bridges . . . . . 13 | 4.4.2. Header Manipulation at Elimination Bridges . . . . . 15 | |||
4.5. Impact of Attacks to Path Choice . . . . . . . . . . . . 13 | 4.5. Control or Signaling Packet Modification . . . . . . . . 16 | |||
4.6. Impact of Attacks by Use Case Industry . . . . . . . . . 13 | 4.6. Control or Signaling Packet Injection . . . . . . . . . . 16 | |||
5. Security Threat Mitigation . . . . . . . . . . . . . . . . . 15 | 4.7. Reconnaissance . . . . . . . . . . . . . . . . . . . . . 16 | |||
4.8. Attacks on Time Sync Mechanisms . . . . . . . . . . . . . 16 | ||||
4.9. Attacks on Path Choice . . . . . . . . . . . . . . . . . 16 | ||||
5. Security Threat Mitigation . . . . . . . . . . . . . . . . . 16 | ||||
5.1. Path Redundancy . . . . . . . . . . . . . . . . . . . . . 16 | 5.1. Path Redundancy . . . . . . . . . . . . . . . . . . . . . 16 | |||
5.2. Integrity Protection . . . . . . . . . . . . . . . . . . 16 | 5.2. Integrity Protection . . . . . . . . . . . . . . . . . . 17 | |||
5.3. DetNet Node Authentication . . . . . . . . . . . . . . . 16 | 5.3. DetNet Node Authentication . . . . . . . . . . . . . . . 17 | |||
5.4. Encryption . . . . . . . . . . . . . . . . . . . . . . . 17 | 5.4. Encryption . . . . . . . . . . . . . . . . . . . . . . . 17 | |||
5.5. Control and Signaling Message Protection . . . . . . . . 17 | 5.5. Control and Signaling Message Protection . . . . . . . . 18 | |||
5.6. Dynamic Performance Analytics . . . . . . . . . . . . . . 17 | 5.6. Dynamic Performance Analytics . . . . . . . . . . . . . . 18 | |||
5.7. Mitigation Summary . . . . . . . . . . . . . . . . . . . 18 | 5.7. Mitigation Summary . . . . . . . . . . . . . . . . . . . 18 | |||
6. Association of Attacks to Use Cases . . . . . . . . . . . . . 19 | 6. Association of Attacks to Use Cases . . . . . . . . . . . . . 20 | |||
6.1. Use Cases by Common Themes . . . . . . . . . . . . . . . 19 | 6.1. Use Cases by Common Themes . . . . . . . . . . . . . . . 20 | |||
6.1.1. Network Layer - AVB/TSN Ethernet . . . . . . . . . . 19 | 6.1.1. Network Layer - AVB/TSN Ethernet . . . . . . . . . . 20 | |||
6.1.2. Central Administration . . . . . . . . . . . . . . . 19 | 6.1.2. Central Administration . . . . . . . . . . . . . . . 21 | |||
6.1.3. Hot Swap . . . . . . . . . . . . . . . . . . . . . . 20 | 6.1.3. Hot Swap . . . . . . . . . . . . . . . . . . . . . . 21 | |||
6.1.4. Data Flow Information Models . . . . . . . . . . . . 20 | 6.1.4. Data Flow Information Models . . . . . . . . . . . . 22 | |||
6.1.5. L2 and L3 Integration . . . . . . . . . . . . . . . . 20 | 6.1.5. L2 and L3 Integration . . . . . . . . . . . . . . . . 22 | |||
6.1.6. End-to-End Delivery . . . . . . . . . . . . . . . . . 20 | 6.1.6. End-to-End Delivery . . . . . . . . . . . . . . . . . 22 | |||
6.1.7. Proprietary Deterministic Ethernet Networks . . . . . 20 | 6.1.7. Proprietary Deterministic Ethernet Networks . . . . . 23 | |||
6.1.8. Replacement for Proprietary Fieldbuses . . . . . . . 20 | 6.1.8. Replacement for Proprietary Fieldbuses . . . . . . . 23 | |||
6.1.9. Deterministic vs Best-Effort Traffic . . . . . . . . 21 | 6.1.9. Deterministic vs Best-Effort Traffic . . . . . . . . 23 | |||
6.1.10. Deterministic Flows . . . . . . . . . . . . . . . . . 21 | 6.1.10. Deterministic Flows . . . . . . . . . . . . . . . . . 24 | |||
6.1.11. Unused Reserved Bandwidth . . . . . . . . . . . . . . 21 | 6.1.11. Unused Reserved Bandwidth . . . . . . . . . . . . . . 24 | |||
6.1.12. Interoperability . . . . . . . . . . . . . . . . . . 21 | 6.1.12. Interoperability . . . . . . . . . . . . . . . . . . 24 | |||
6.1.13. Cost Reductions . . . . . . . . . . . . . . . . . . . 21 | 6.1.13. Cost Reductions . . . . . . . . . . . . . . . . . . . 25 | |||
6.1.14. Insufficiently Secure Devices . . . . . . . . . . . . 22 | 6.1.14. Insufficiently Secure Devices . . . . . . . . . . . . 25 | |||
6.1.15. DetNet Network Size . . . . . . . . . . . . . . . . . 22 | 6.1.15. DetNet Network Size . . . . . . . . . . . . . . . . . 25 | |||
6.1.16. Multiple Hops . . . . . . . . . . . . . . . . . . . . 22 | 6.1.16. Multiple Hops . . . . . . . . . . . . . . . . . . . . 26 | |||
6.1.17. Level of Service . . . . . . . . . . . . . . . . . . 22 | 6.1.17. Level of Service . . . . . . . . . . . . . . . . . . 26 | |||
6.1.18. Bounded Latency . . . . . . . . . . . . . . . . . . . 23 | 6.1.18. Bounded Latency . . . . . . . . . . . . . . . . . . . 27 | |||
6.1.19. Low Latency . . . . . . . . . . . . . . . . . . . . . 23 | 6.1.19. Low Latency . . . . . . . . . . . . . . . . . . . . . 27 | |||
6.1.20. Symmetrical Path Delays . . . . . . . . . . . . . . . 23 | 6.1.20. Symmetrical Path Delays . . . . . . . . . . . . . . . 27 | |||
6.1.21. Reliability and Availability . . . . . . . . . . . . 23 | 6.1.21. Reliability and Availability . . . . . . . . . . . . 27 | |||
6.1.22. Redundant Paths . . . . . . . . . . . . . . . . . . . 24 | 6.1.22. Redundant Paths . . . . . . . . . . . . . . . . . . . 28 | |||
6.1.23. Security Measures . . . . . . . . . . . . . . . . . . 24 | 6.1.23. Security Measures . . . . . . . . . . . . . . . . . . 28 | |||
6.2. Attack Types by Use Case Common Theme . . . . . . . . . . 24 | 6.2. Attack Types by Use Case Common Theme . . . . . . . . . . 28 | |||
7. Appendix A: DetNet Draft Security-Related Statements . . . . 26 | 7. Appendix A: DetNet Draft Security-Related Statements . . . . 30 | |||
7.1. Architecture (draft 8) . . . . . . . . . . . . . . . . . 27 | 7.1. Architecture (draft 8) . . . . . . . . . . . . . . . . . 31 | |||
7.1.1. Fault Mitigation (sec 4.5) . . . . . . . . . . . . . 27 | 7.1.1. Fault Mitigation (sec 4.5) . . . . . . . . . . . . . 31 | |||
7.1.2. Security Considerations (sec 7) . . . . . . . . . . . 27 | 7.1.2. Security Considerations (sec 7) . . . . . . . . . . . 31 | |||
7.2. Data Plane Alternatives (draft 4) . . . . . . . . . . . . 28 | 7.2. Data Plane Alternatives (draft 4) . . . . . . . . . . . . 32 | |||
7.2.1. Security Considerations (sec 7) . . . . . . . . . . . 28 | 7.2.1. Security Considerations (sec 7) . . . . . . . . . . . 32 | |||
7.3. Problem Statement (draft 5) . . . . . . . . . . . . . . . 28 | 7.3. Problem Statement (draft 5) . . . . . . . . . . . . . . . 32 | |||
7.3.1. Security Considerations (sec 5) . . . . . . . . . . . 28 | 7.3.1. Security Considerations (sec 5) . . . . . . . . . . . 32 | |||
7.4. Use Cases (draft 11) . . . . . . . . . . . . . . . . . . 29 | 7.4. Use Cases (draft 11) . . . . . . . . . . . . . . . . . . 33 | |||
7.4.1. (Utility Networks) Security Current Practices and | 7.4.1. (Utility Networks) Security Current Practices and | |||
Limitations (sec 3.2.1) . . . . . . . . . . . . . . . 29 | Limitations (sec 3.2.1) . . . . . . . . . . . . . . . 33 | |||
7.4.2. (Utility Networks) Security Trends in Utility | 7.4.2. (Utility Networks) Security Trends in Utility | |||
Networks (sec 3.3.3) . . . . . . . . . . . . . . . . 30 | Networks (sec 3.3.3) . . . . . . . . . . . . . . . . 34 | |||
7.4.3. (BAS) Security Considerations (sec 4.2.4) . . . . . . 32 | 7.4.3. (BAS) Security Considerations (sec 4.2.4) . . . . . . 36 | |||
7.4.4. (6TiSCH) Security Considerations (sec 5.3.3) . . . . 32 | 7.4.4. (6TiSCH) Security Considerations (sec 5.3.3) . . . . 36 | |||
7.4.5. (Cellular radio) Security Considerations (sec 6.1.5) 32 | 7.4.5. (Cellular radio) Security Considerations (sec 6.1.5) 36 | |||
7.4.6. (Industrial M2M) Communication Today (sec 7.2) . . . 33 | 7.4.6. (Industrial M2M) Communication Today (sec 7.2) . . . 37 | |||
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 33 | 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 37 | |||
9. Security Considerations . . . . . . . . . . . . . . . . . . . 33 | 9. Security Considerations . . . . . . . . . . . . . . . . . . . 37 | |||
10. Informative References . . . . . . . . . . . . . . . . . . . 33 | 10. Informative References . . . . . . . . . . . . . . . . . . . 37 | |||
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 34 | Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 38 | |||
1. Introduction | 1. Introduction | |||
Security is of particularly high importance in DetNet networks | Security is of particularly high importance in DetNet networks | |||
because many of the use cases which are enabled by DetNet | because many of the use cases which are enabled by DetNet | |||
[I-D.ietf-detnet-use-cases] include control of physical devices | [I-D.ietf-detnet-use-cases] include control of physical devices | |||
(power grid components, industrial controls, building controls) which | (power grid components, industrial controls, building controls) which | |||
can have high operational costs for failure, and present potentially | can have high operational costs for failure, and present potentially | |||
attractive targets for cyber-attackers. | attractive targets for cyber-attackers. | |||
skipping to change at page 5, line 25 ¶ | skipping to change at page 5, line 27 ¶ | |||
the flow | the flow | |||
o Provide explicit routes for DetNet flows that do not rapidly | o Provide explicit routes for DetNet flows that do not rapidly | |||
change with the network topology | change with the network topology | |||
o Distribute data from DetNet flow packets over time and/or space to | o Distribute data from DetNet flow packets over time and/or space to | |||
ensure delivery of each packet's data' in spite of the loss of a | ensure delivery of each packet's data' in spite of the loss of a | |||
path | path | |||
This draft includes sections on threat modeling and analysis, threat | This draft includes sections on threat modeling and analysis, threat | |||
impact and mitigation, and the association of various attacks with | impact and mitigation, and the association of attacks with use cases | |||
various use cases both by industry and based on the Use Case Common | based on the Use Case Common Themes section of the DetNet Use Cases | |||
Themes section of the DetNet Use Cases draft | draft [I-D.ietf-detnet-use-cases]. | |||
[I-D.ietf-detnet-use-cases]. | ||||
This draft also provides context for the DetNet security | This draft also provides context for the DetNet security | |||
considerations by collecting into one place Section 7 the various | considerations by collecting into one place Section 7 the various | |||
remarks about security from the various DetNet drafts (Use Cases, | remarks about security from the various DetNet drafts (Use Cases, | |||
Architecture, etc). This text is duplicated here primarily because | Architecture, etc). This text is duplicated here primarily because | |||
the DetNet working group has elected not to produce a Requirements | the DetNet working group has elected not to produce a Requirements | |||
draft and thus collectively these statements are as close as we have | draft and thus collectively these statements are as close as we have | |||
to "DetNet Security Requirements". | to "DetNet Security Requirements". | |||
2. Abbreviations | 2. Abbreviations | |||
skipping to change at page 6, line 20 ¶ | skipping to change at page 6, line 22 ¶ | |||
many Affected users, Discoverability. | many Affected users, Discoverability. | |||
PTP Precision Time Protocol [IEEE1588] | PTP Precision Time Protocol [IEEE1588] | |||
3. Security Threats | 3. Security Threats | |||
This section presents a threat model, and analyzes the possible | This section presents a threat model, and analyzes the possible | |||
threats in a DetNet-enabled network. | threats in a DetNet-enabled network. | |||
We distinguish control plane threats from data plane threats. The | We distinguish control plane threats from data plane threats. The | |||
attack surface may be the same, but the types of attacks are | attack surface may be the same, but the types of attacks as well as | |||
different. For example, a delay attack is more relevant to data | the motivation behind them, are different. For example, a delay | |||
plane than to control plane. There is also a difference in terms of | attack is more relevant to data plane than to control plane. There | |||
security solutions: the way you secure the data plane is often | is also a difference in terms of security solutions: the way you | |||
different than the way you secure the control plane. | secure the data plane is often different than the way you secure the | |||
control plane. | ||||
3.1. Threat Model | 3.1. Threat Model | |||
The threat model used in this memo is based on the threat model of | The threat model used in this memo is based on the threat model of | |||
Section 3.1 of [RFC7384]. This model classifies attackers based on | Section 3.1 of [RFC7384]. This model classifies attackers based on | |||
two criteria: | two criteria: | |||
o Internal vs. external: internal attackers either have access to a | o Internal vs. external: internal attackers either have access to a | |||
trusted segment of the network or possess the encryption or | trusted segment of the network or possess the encryption or | |||
authentication keys. External attackers, on the other hand, do | authentication keys. External attackers, on the other hand, do | |||
not have the keys and have access only to the encrypted or | not have the keys and have access only to the encrypted or | |||
authenticated traffic. | authenticated traffic. | |||
o Man in the Middle (MITM) vs. packet injector: MITM attackers are | o Man in the Middle (MITM) vs. packet injector: MITM attackers are | |||
located in a position that allows interception and modification of | located in a position that allows interception and modification of | |||
in-flight protocol packets, whereas a traffic injector can only | in-flight protocol packets, whereas a traffic injector can only | |||
attack by generating protocol packets. | attack by generating protocol packets. | |||
Care has also been taken to adhere to Section 5 of [RFC3552], both | ||||
with respect to what attacks are considered out-of-scope for this | ||||
document, but also what is considered to be the most common threats | ||||
(explored furhter in Section 3.2. Most of the direct threats to | ||||
DetNet are Active attacks, but it is highly suggested that DetNet | ||||
application developers take appropriate measures to protect the | ||||
content of the streams from passive attacks. | ||||
DetNet-Service, one of the service scenarios described in | DetNet-Service, one of the service scenarios described in | |||
[I-D.varga-detnet-service-model], is the case where a service | [I-D.varga-detnet-service-model], is the case where a service | |||
connects DetNet networking islands, i.e. two or more otherwise | connects DetNet networking islands, i.e. two or more otherwise | |||
independent DetNet network domains are connected via a link that is | independent DetNet network domains are connected via a link that is | |||
not intrinsically part of either network. This implies that there | not intrinsically part of either network. This implies that there | |||
could be DetNet traffic flowing over a non-DetNet link, which may | could be DetNet traffic flowing over a non-DetNet link, which may | |||
provide an attacker with an advantageous opportunity to tamper with | provide an attacker with an advantageous opportunity to tamper with | |||
DetNet traffic. The security properties of non-DetNet links are | DetNet traffic. The security properties of non-DetNet links are | |||
outside of the scope of DetNet Security, but it should be noted that | outside of the scope of DetNet Security, but it should be noted that | |||
use of non-DetNet services to interconnect DetNet networks merits | use of non-DetNet services to interconnect DetNet networks merits | |||
skipping to change at page 7, line 19 ¶ | skipping to change at page 7, line 31 ¶ | |||
3.2.1. Delay | 3.2.1. Delay | |||
3.2.1.1. Delay Attack | 3.2.1.1. Delay Attack | |||
An attacker can maliciously delay DetNet data flow traffic. By | An attacker can maliciously delay DetNet data flow traffic. By | |||
delaying the traffic, the attacker can compromise the service of | delaying the traffic, the attacker can compromise the service of | |||
applications that are sensitive to high delays or to high delay | applications that are sensitive to high delays or to high delay | |||
variation. | variation. | |||
3.2.2. DetNet Flow Identification | 3.2.2. DetNet Flow Modification or Spoofing | |||
3.2.2.1. DetNet Flow Modification or Spoofing | ||||
An attacker can modify some header fields of en route packets in a | An attacker can modify some header fields of en route packets in a | |||
way that causes the DetNet flow identification mechanisms to | way that causes the DetNet flow identification mechanisms to | |||
misclassify the flow. Alternatively, the attacker can inject traffic | misclassify the flow. Alternatively, the attacker can inject traffic | |||
that is tailored to appear as if it belongs to a legitimate DetNet | that is tailored to appear as if it belongs to a legitimate DetNet | |||
flow. The potential consequence is that the DetNet flow resource | flow. The potential consequence is that the DetNet flow resource | |||
allocation cannot guarantee the performance that is expected when the | allocation cannot guarantee the performance that is expected when the | |||
flow identification works correctly. | flow identification works correctly. | |||
Note that in some cases there may be an explicit DetNet header, but | ||||
in some cases the flow identification may be based on fields from the | ||||
L3/L4 headers. If L3/L4 headers are involved, for purposes of this | ||||
draft we assume they are encrypted and/or integrity-protected from | ||||
external attackers. | ||||
3.2.3. Resource Segmentation or Slicing | 3.2.3. Resource Segmentation or Slicing | |||
3.2.3.1. Inter-segment Attack | 3.2.3.1. Inter-segment Attack | |||
An attacker can inject traffic, consuming network device resources, | An attacker can inject traffic, consuming network device resources, | |||
thereby affecting DetNet flows. This can be performed using non- | thereby affecting DetNet flows. This can be performed using non- | |||
DetNet traffic that affects DetNet traffic, or by using DetNet | DetNet traffic that affects DetNet traffic, or by using DetNet | |||
traffic from one DetNet flow that affects traffic from different | traffic from one DetNet flow that affects traffic from different | |||
DetNet flows. | DetNet flows. | |||
skipping to change at page 9, line 23 ¶ | skipping to change at page 9, line 28 ¶ | |||
3.2.6.2. Control or Signaling Packet Injection | 3.2.6.2. Control or Signaling Packet Injection | |||
An attacker can maliciously inject control packets in order to | An attacker can maliciously inject control packets in order to | |||
disrupt or manipulate the DetNet path/resource allocation. | disrupt or manipulate the DetNet path/resource allocation. | |||
3.2.7. Scheduling or Shaping | 3.2.7. Scheduling or Shaping | |||
3.2.7.1. Reconnaissance | 3.2.7.1. Reconnaissance | |||
A passive eavesdropper can gather information about en route DetNet | A passive eavesdropper can identify DetNet flows and then gather | |||
flows, e.g., the number of DetNet flows, their bandwidths, and their | information about en route DetNet flows, e.g., the number of DetNet | |||
schedules. The gathered information can later be used to invoke | flows, their bandwidths, and their schedules. The gathered | |||
other attacks on some or all of the flows. | information can later be used to invoke other attacks on some or all | |||
of the flows. | ||||
Note that in some cases DetNet flows may be identified based on an | ||||
explicit DetNet header, but in some cases the flow identification may | ||||
be based on fields from the L3/L4 headers. If L3/L4 headers are | ||||
involved, for purposes of this draft we assume they are encrypted | ||||
and/or integrity-protected from external attackers. | ||||
3.2.8. Time Synchronization Mechanisms | 3.2.8. Time Synchronization Mechanisms | |||
An attacker can use any of the attacks described in [RFC7384] to | An attacker can use any of the attacks described in [RFC7384] to | |||
attack the synchronization protocol, thus affecting the DetNet | attack the synchronization protocol, thus affecting the DetNet | |||
service. | service. | |||
3.3. Threat Summary | 3.3. Threat Summary | |||
A summary of the attacks that were discussed in this section is | A summary of the attacks that were discussed in this section is | |||
skipping to change at page 10, line 38 ¶ | skipping to change at page 10, line 40 ¶ | |||
+-----------------------------------------+----+----+----+----+ | +-----------------------------------------+----+----+----+----+ | |||
|Reconnaissance | + | | + | | | |Reconnaissance | + | | + | | | |||
+-----------------------------------------+----+----+----+----+ | +-----------------------------------------+----+----+----+----+ | |||
|Attacks on Time Sync Mechanisms | + | + | + | + | | |Attacks on Time Sync Mechanisms | + | + | + | + | | |||
+-----------------------------------------+----+----+----+----+ | +-----------------------------------------+----+----+----+----+ | |||
Figure 1: Threat Analysis Summary | Figure 1: Threat Analysis Summary | |||
4. Security Threat Impacts | 4. Security Threat Impacts | |||
This section describes the impact of the attacks described in | This section describes and rates the impact of the attacks described | |||
Section 3. Mitigations are discussed further in Section 5. | in Section 3. In this section, the impacts as described assume that | |||
the associated mitigation is not present or has failed. Mitigations | ||||
are discussed in Section 5. | ||||
In computer security, the impact (or consequence) of an incident can | In computer security, the impact (or consequence) of an incident can | |||
be measured in loss of confidentiality, integrity or availability of | be measured in loss of confidentiality, integrity or availability of | |||
information. In other words, this section describes the effect of a | information. | |||
successful attack. The scope is limited to the effect of a | ||||
successful attack on DetNet itself, not the applications that _use_ | DetNet raises these stakes significantly for OT applications, | |||
Detnet as this is highly application specific. | particularly those which may have been designed to run in an OT-only | |||
environment and thus may not have been designed for security in an IT | ||||
environment with its associated devices, services and protocols. | ||||
The severity of various components of the impact of a successful | ||||
vulnerability exploit to use cases by industry is available in more | ||||
detail in [I-D.ietf-detnet-use-cases]. Each of the use cases in the | ||||
DetNet Use Cases draft is represented in the table below, including | ||||
Pro Audio, Electrical Utilities, Industrial M2M (split into two | ||||
areas, M2M Data Gathering and M2M Control Loop), and others. | ||||
Components of Impact (left column) include Criticality of Failure, | ||||
Effects of Failure, Recovery, and DetNet Functional Dependence. | ||||
Criticality of failure summarizes the seriousness of the impact. The | ||||
impact of a resulting failure can affect many different metrics that | ||||
vary greatly in scope and severity. In order to reduce the number of | ||||
variables, only the following were included: Financial, Health and | ||||
Safety, People well being, Affect on a single organization, and | ||||
affect on multiple organizations. Recovery outlines how long it | ||||
would take for an affected use case to get back to its pre-failure | ||||
state (Recovery time objective, RTO), and how much of the original | ||||
service would be lost in between the time of service failure and | ||||
recovery to original state (Recovery Point Objective, RPO). DetNet | ||||
dependence maps how much the following DetNet service objectives | ||||
contribute to impact of failure: Time dependency, data integrity, | ||||
source node integrity, availability, latency/jitter. | ||||
The scale of the Impact mappings is low, medium, and high. In some | ||||
use cases there may be a multitude of specific applications in which | ||||
DetNet is used. For simplicity this section attempts to average the | ||||
varied impacts of different applications. This section does not | ||||
address the overall risk of a certain impact which would require the | ||||
likelihood of a failure happening. | ||||
In practice any such ratings will vary from case to case; the ratings | ||||
shown here are given as examples. | ||||
Table, Part One (of Two) | ||||
+------------------+-----------------------------------------+-----+ | ||||
| | Pro A | Util | Bldg |Wire- | Cell |M2M |M2M | | ||||
| | | | | less | |Data |Ctrl | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Criticality | Med | Hi | Low | Med | Med | Med | Med | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Effects | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Financial | Med | Hi | Med | Med | Low | Med | Med | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Health/Safety | Med | Hi | Hi | Med | Med | Med | Med | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| People WB | Med | Hi | Hi | Low | Hi | Low | Low | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Effect 1 org | Hi | Hi | Med | Hi | Med | Med | Med | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Effect >1 org | Med | Hi | Low | Med | Med | Med | Med | | ||||
+------------------+-----------------------------------------+-----+ | ||||
|Recovery | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Recov Time Obj | Med | Hi | Med | Hi | Hi | Hi | Hi | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Recov Point Obj | Med | Hi | Low | Med | Low | Hi | Hi | | ||||
+------------------+-----------------------------------------+-----+ | ||||
|DetNet Dependence | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Time Dependency | Hi | Hi | Low | Hi | Med | Low | Hi | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Latency/Jitter | Hi | Hi | Med | Med | Low | Low | Hi | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Data Integrity | Hi | Hi | Med | Hi | Low | Hi | Low | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Src Node Integ | Hi | Hi | Med | Hi | Med | Hi | Hi | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Availability | Hi | Hi | Med | Hi | Low | Hi | Hi | | ||||
+------------------+-----------------------------------------+-----+ | ||||
Table, Part Two (of Two) | ||||
+------------------+--------------------------+ | ||||
| | Mining | Block | Network | | ||||
| | | Chain | Slicing | | ||||
+------------------+--------------------------+ | ||||
| Criticality | Hi | Med | Hi | | ||||
+------------------+--------------------------+ | ||||
| Effects | ||||
+------------------+--------------------------+ | ||||
| Financial | Hi | Hi | Hi | | ||||
+------------------+--------------------------+ | ||||
| Health/Safety | Hi | Low | Med | | ||||
+------------------+--------------------------+ | ||||
| People WB | Hi | Low | Med | | ||||
+------------------+--------------------------+ | ||||
| Effect 1 org | Hi | Hi | Hi | | ||||
+------------------+--------------------------+ | ||||
| Effect >1 org | Hi | Low | Hi | | ||||
+------------------+--------------------------+ | ||||
|Recovery | ||||
+------------------+--------------------------+ | ||||
| Recov Time Obj | Hi | Low | Hi | | ||||
+------------------+--------------------------+ | ||||
| Recov Point Obj | Hi | Low | Hi | | ||||
+------------------+--------------------------+ | ||||
|DetNet Dependence | ||||
+------------------+--------------------------+ | ||||
| Time Dependency | Hi | Low | Hi | | ||||
+------------------+--------------------------+ | ||||
| Latency/Jitter | Hi | Low | Hi | | ||||
+------------------+--------------------------+ | ||||
| Data Integrity | Hi | Hi | Hi | | ||||
+------------------+--------------------------+ | ||||
| Src Node Integ | Hi | Hi | Hi | | ||||
+------------------+--------------------------+ | ||||
| Availability | Hi | Hi | Hi | | ||||
+------------------+--------------------------+ | ||||
Figure 2: Impact of Attacks by Use Case Industry | ||||
The rest of this section will cover impact of the different groups in | ||||
more detail. | ||||
4.1. Delay-Attacks | 4.1. Delay-Attacks | |||
4.1.1. Data Plane Delay Attacks | 4.1.1. Data Plane Delay Attacks | |||
Dropped messages can result in stream instability. If only a single | Severely delayed messages in a DetNet link can result in the same | |||
path is used, the entire stream can be disrupted. In a multipath | behavior as dropped messages in ordinary networks as the services | |||
scenario, large delays on one stream can lead to increased buffer and | attached to the stream has strict deterministic requirements. | |||
CPU resources on the elimination bridge. | ||||
If the attack is carried out on a sole link (i.e. no multipath), the | For a single path scenario, disruption is a real possibility, whereas | |||
DetNet stream can be interrupted and result in outages. | in a multipath scenario, large delays or instabilities in one stream | |||
can lead to increased buffer and CPU resources on the elimination | ||||
bridge. | ||||
4.1.2. Control Plane Delay Attacks | 4.1.2. Control Plane Delay Attacks | |||
In and of itself, this is not directly a threat, the effects of | In and of itself, this is not directly a threat to the DetNet | |||
delaying control messages can have quite adverse effects later. | service, but the effects of delaying control messages can have quite | |||
adverse effects later. | ||||
Delayed messages for tear-down can lead to resource leakage if a | ||||
stream is not torn down at the correct time. This can in turn result | ||||
in failure to allocate new streams giving rise to a denial of service | ||||
attack. | ||||
In the case where an End-point should be added to a multicast, | ||||
failure to deliver said signalling message will prevent the new EP | ||||
from receiving expected frames. | ||||
Likewise, when an EP should be removed from a multicast group, | o Delayed tear-down can lead to resource leakage, which in turn can | |||
delaying such messages can lead to loss of privacy as the EP will | result in failure to allocate new streams finally giving rise to a | |||
continue to receive messages even after it is removed. | denial of service attack. | |||
4.2. Flow Identification and Spoofing | o Failure to deliver, or severely delaying, signalling messages | |||
adding an end-point to a multicast-group will prevent the new EP | ||||
from receiving expected frames thus disrupting expected behavior. | ||||
4.2.1. Flow identification | o Delaying messages removing an EP from a group can lead to loss of | |||
privacy as the EP will continue to receive messages even after it | ||||
is supposedly removed. | ||||
Of all the attacks, this is one of the most difficult to detect and | 4.2. Flow Modification and Spoofing | |||
counter. Often, an attacker will start out by observing the traffic | ||||
going through the network and use the knowledge gathered in this | ||||
phase to mount future attacks. | ||||
The attacker can, at their leisure, observe over time all aspects of | 4.2.1. Flow Modification | |||
the messaging and signalling, learning the intent and purpose of all | ||||
traffic flows. At some later date, possibly at an important time in | ||||
an operational context, the attacker can launch a multi-faceted | ||||
attack, possibly in conjunction with some demand for ransom. | ||||
The flow-id in the header of the data plane-messages gives an | ToDo. | |||
attacker a very reliable identifier for DetNet traffic, and this | ||||
traffic has a high probability of going to lucrative targets. | ||||
4.2.2. Spoofing | 4.2.2. Spoofing | |||
4.2.2.1. Dataplane Spoofing | 4.2.2.1. Dataplane Spoofing | |||
Spoofing dataplane messages can result in increased resource | Spoofing dataplane messages can result in increased resource | |||
consumptions on the bridges throughout the network as it will | consumptions on the bridges throughout the network as it will | |||
increase buffer usage and CPU utilization. This can lead to resource | increase buffer usage and CPU utilization. This can lead to resource | |||
exhaustion and/or increased delay. | exhaustion and/or increased delay. | |||
skipping to change at page 12, line 25 ¶ | skipping to change at page 14, line 39 ¶ | |||
can be forwarded through the network, using part of the allocated | can be forwarded through the network, using part of the allocated | |||
bandwidth. This in turn can cause legitimate messages to be dropped | bandwidth. This in turn can cause legitimate messages to be dropped | |||
when the budget has been exhausted. | when the budget has been exhausted. | |||
Finally, the endpoint will have to deal with invalid messages being | Finally, the endpoint will have to deal with invalid messages being | |||
delivered to the endpoint instead of (or in addition to) a valid | delivered to the endpoint instead of (or in addition to) a valid | |||
message. | message. | |||
4.2.2.2. Control Plane Spoofing | 4.2.2.2. Control Plane Spoofing | |||
A successful control plane spoofing-attack has a very large | A successful control plane spoofing-attack will potentionally have | |||
potential. It can do anything from modifying existing streams by | adverse effects. It can do virtually anything from: | |||
changing the available bandwidth, add or remove endpoints or drop the | ||||
stream altogether. It would also be possible to falsely create new | o modifying existing streams by changing the available bandwidth | |||
streams, which could give an attacker the ability to exhaust the | ||||
systems resources, or just enable a high quality DetNet stream | o add or remove endpoints from a stream | |||
outside the Network engineer's control. | ||||
o drop streams completly | ||||
o falsely create new streams (exhaust the systems resources, or to | ||||
enable streams outside the Network engineer's control) | ||||
4.3. Segmentation attacks (injection) | 4.3. Segmentation attacks (injection) | |||
4.3.1. Data Plane Segmentation | 4.3.1. Data Plane Segmentation | |||
Injection of false messages in a DetNet stream could lead to | Injection of false messages in a DetNet stream could lead to | |||
exhaustion of the available bandwidth for a stream if the bridges | exhaustion of the available bandwidth for a stream if the bridges | |||
accounts false messages to the stream's budget. | accounts false messages to the stream's budget. | |||
In a multipath scenario, injected messages will cause an increased | In a multipath scenario, injected messages will cause increased CPU | |||
CPU utilization on elimination bridges and if enough paths are | utilization in elimination bridges. If enough paths are subject to | |||
subject to malicious injection, the legitimate messages could be | malicious injection, the legitimate messages can be dropped. | |||
dropped. Likewise it can cause an increase in buffer usage. In | Likewise it can cause an increase in buffer usage. In total, it will | |||
total, this will consume more resources on the bridges than normal, | consume more resources in the bridges than normal, giving rise to a | |||
giving rise to a potential resource exhaustion attack on the bridges. | resource exhaustion attack on the bridges. | |||
If a stream is interrupted, the end application will be affected by | If a stream is interrupted, the end application will be affected by | |||
what is now a non-deterministic stream. | what is now a non-deterministic stream. | |||
4.3.2. Control Plane segmentation | 4.3.2. Control Plane segmentation | |||
A successful Control Plane segmentation attack will cause control | A successful Control Plane segmentation attack control messages to be | |||
messages to be interpreted by nodes in the network. This has the | interpreted by nodes in the network, unbeknownst to the central | |||
potential to create new streams (exhausting resources), drop existing | controller or the network engineer. This has the potential to create | |||
(denial of service), add/remove end-stations to a multicast group | ||||
(loss of privacy) or modify the stream attributes (reducing available | ||||
bandwidth, or increasing it so that new streams cannot reserve a | ||||
path). | ||||
In short, this means that you cannot trust the stream reservation | o new streams (exhausting resources) | |||
properties or the network itself. | ||||
As with spoofing, if an attacker is able to inject control-plane | o drop existing (denial of service) | |||
messages and the receiving end does not detect it, the receiving | ||||
station must be able to. | o add/remove end-stations to a multicast group (loss of privacy) | |||
o modify the stream attributes (affecting available bandwidth | ||||
4.4. Replication and Elimination | 4.4. Replication and Elimination | |||
The Replication and Elimination is relevant only to Data Plane | The Replication and Elimination is relevant only to Data Plane | |||
messages as Signalling is not subject to multipath routing. | messages as Signalling is not subject to multipath routing. | |||
4.4.1. Increased Attack Surface | 4.4.1. Increased Attack Surface | |||
Covered briefly in Section 4.3 | Covered briefly in Section 4.3 | |||
4.4.2. Header Manipulation at Elimination Bridges | 4.4.2. Header Manipulation at Elimination Bridges | |||
Covered briefly in Section 4.3 | Covered briefly in Section 4.3 | |||
4.5. Impact of Attacks to Path Choice | 4.5. Control or Signaling Packet Modification | |||
This is covered in part in Section 4.3, and as with Replication and | ToDo. | |||
Elimination (Section 4.4, this is relevant for DataPlane messages. | ||||
4.6. Impact of Attacks by Use Case Industry | 4.6. Control or Signaling Packet Injection | |||
This section rates the severity of various components of the impact | ToDo. | |||
of a successful vulnerability exploit to use cases by industry as | ||||
described in [I-D.ietf-detnet-use-cases], including Pro Audio, | ||||
Electrical Utilities, Building Automation, Wireless for Industrial, | ||||
Cellular Radio, and Industrial M2M (split into two areas, M2M Data | ||||
Gathering and M2M Control Loop). | ||||
Components of Impact (left column) include Criticality of Failure, | 4.7. Reconnaissance | |||
Effects of Failure, Recovery, and DetNet Functional Dependence. | ||||
Criticality of failure summarizes the seriousness of the impact. The | ||||
impact of a resulting failure can affect many different metrics that | ||||
vary greatly in scope and severity. In order to reduce the number of | ||||
variables, the following were included: Financial, Health and Safety, | ||||
People well being, Affect on a single organization, and affect on | ||||
multiple organizations. Recovery outlines how long it would take for | ||||
an affected use case to get back to its pre-failure state (Recovery | ||||
time objective, RTO), and how much of the original service would be | ||||
lost in between the time of service failure and recovery to original | ||||
state (Recovery Point Objective, RPO). DetNET dependence maps how | ||||
much the following DetNet service objectives contribute to impact of | ||||
failure: Time dependency, data integrity, source node integrity, | ||||
availability, latency/jitter. | ||||
The scale of the Impact mappings is low, medium, and high. In some | Of all the attacks, this is one of the most difficult to detect and | |||
use cases there may be a multitude of specific applications in which | counter. Often, an attacker will start out by observing the traffic | |||
DetNET is used. For simplicity this section attempts to average the | going through the network and use the knowledge gathered in this | |||
varied impacts of different applications. This section does not | phase to mount future attacks. | |||
address the overall risk of a certain impact which would require the | ||||
likelihood of a failure happening. | ||||
In practice any such ratings will vary from case to case; the ratings | The attacker can, at their leisure, observe over time all aspects of | |||
shown here are given as examples. | the messaging and signalling, learning the intent and purpose of all | |||
traffic flows. At some later date, possibly at an important time in | ||||
an operational context, the attacker can launch a multi-faceted | ||||
attack, possibly in conjunction with some demand for ransom. | ||||
+------------------+-----------------------------------------+-----+ | The flow-id in the header of the data plane-messages gives an | |||
| | Pro A | Util | Bldg |Wire- | Cell |M2M |M2M | | attacker a very reliable identifier for DetNet traffic, and this | |||
| | | | | less | |Data |Ctrl | | traffic has a high probability of going to lucrative targets. | |||
+------------------+-----------------------------------------+-----+ | ||||
| Criticality | Med | Hi | Low | Med | Med | Med | Med | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Effects | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Financial | Med | Hi | Med | Med | Low | Med | Med | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Health/Safety | Med | Hi | Hi | Med | Med | Med | Med | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| People WB | Med | Hi | Hi | Low | Hi | Low | Low | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Effect 1 org | Hi | Hi | Med | Hi | Med | Med | Med | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Effect >1 org | Med | Hi | Low | Med | Med | Med | Med | | ||||
+------------------+-----------------------------------------+-----+ | ||||
|Recovery | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Recov Time Obj | Med | Hi | Med | Hi | Hi | Hi | Hi | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Recov Point Obj | Med | Hi | Low | Med | Low | Hi | Hi | | ||||
+------------------+-----------------------------------------+-----+ | ||||
|DetNet Dependence | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Time Dependency | Hi | Hi | Low | Hi | Med | Low | Hi | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Latency/Jitter | Hi | Hi | Med | Med | Low | Low | Hi | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Data Integrity | Hi | Hi | Med | Hi | Low | Hi | Low | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Src Node Integ | Hi | Hi | Med | Hi | Med | Hi | Hi | | ||||
+------------------+-----------------------------------------+-----+ | ||||
| Availability | Hi | Hi | Med | Hi | Low | Hi | Hi | | ||||
+------------------+-----------------------------------------+-----+ | ||||
Figure 2: Impact of Attacks by Use Case Industry | 4.8. Attacks on Time Sync Mechanisms | |||
ToDo. | ||||
4.9. Attacks on Path Choice | ||||
This is covered in part in Section 4.3, and as with Replication and | ||||
Elimination (Section 4.4, this is relevant for DataPlane messages. | ||||
5. Security Threat Mitigation | 5. Security Threat Mitigation | |||
This section describes a set of measures that can be taken to | This section describes a set of measures that can be taken to | |||
mitigate the attacks described in Section 3. These mitigations | mitigate the attacks described in Section 3. These mitigations | |||
should be viewed as a toolset that includes several different and | should be viewed as a toolset that includes several different and | |||
diverse tools. Each application or system will typically use a | diverse tools. Each application or system will typically use a | |||
subset of these tools, based on a system-specific threat analysis. | subset of these tools, based on a system-specific threat analysis. | |||
5.1. Path Redundancy | 5.1. Path Redundancy | |||
skipping to change at page 18, line 21 ¶ | skipping to change at page 19, line 14 ¶ | |||
+----------------------+---------------------+---------------------+ | +----------------------+---------------------+---------------------+ | |||
| Attack | Impact | Mitigations | | | Attack | Impact | Mitigations | | |||
+----------------------+---------------------+---------------------+ | +----------------------+---------------------+---------------------+ | |||
|Delay Attack |-Non-deterministic |-Path redundancy | | |Delay Attack |-Non-deterministic |-Path redundancy | | |||
| | delay |-Performance | | | | delay |-Performance | | |||
| |-Data disruption | analytics | | | |-Data disruption | analytics | | |||
| |-Increased resource | | | | |-Increased resource | | | |||
| | consumption | | | | | consumption | | | |||
+----------------------+---------------------+---------------------+ | +----------------------+---------------------+---------------------+ | |||
|Reconnaissance |-Enabler for other |-Encryption | | ||||
| | attacks | | | ||||
+----------------------+---------------------+---------------------+ | ||||
|DetNet Flow Modificat-|-Increased resource |-Path redundancy | | |DetNet Flow Modificat-|-Increased resource |-Path redundancy | | |||
|ion or Spoofing | consumption |-Integrity protection| | |ion or Spoofing | consumption |-Integrity protection| | |||
| |-Data disruption |-DetNet Node | | | |-Data disruption |-DetNet Node | | |||
| | | authentication | | | | | authentication | | |||
+----------------------+---------------------+---------------------+ | +----------------------+---------------------+---------------------+ | |||
|Inter-Segment Attack |-Increased resource |-Path redundancy | | |Inter-Segment Attack |-Increased resource |-Path redundancy | | |||
| | consumption |-Performance | | | | consumption |-Performance | | |||
| |-Data disruption | analytics | | | |-Data disruption | analytics | | |||
+----------------------+---------------------+---------------------+ | +----------------------+---------------------+---------------------+ | |||
|Replication: Increased|-All impacts of other|-Integrity protection| | |Replication: Increased|-All impacts of other|-Integrity protection| | |||
skipping to change at page 19, line 8 ¶ | skipping to change at page 19, line 52 ¶ | |||
| |-Non-deterministic | | | | |-Non-deterministic | | | |||
| | delay | | | | | delay | | | |||
| |-Data disruption | | | | |-Data disruption | | | |||
+----------------------+---------------------+---------------------+ | +----------------------+---------------------+---------------------+ | |||
|Control or Signaling |-Increased resource |-Control message | | |Control or Signaling |-Increased resource |-Control message | | |||
|Packet Injection | consumption | protection | | |Packet Injection | consumption | protection | | |||
| |-Non-deterministic | | | | |-Non-deterministic | | | |||
| | delay | | | | | delay | | | |||
| |-Data disruption | | | | |-Data disruption | | | |||
+----------------------+---------------------+---------------------+ | +----------------------+---------------------+---------------------+ | |||
|Reconnaissance |-Enabler for other |-Encryption | | ||||
| | attacks | | | ||||
+----------------------+---------------------+---------------------+ | ||||
|Attacks on Time Sync |-Non-deterministic |-Path redundancy | | |Attacks on Time Sync |-Non-deterministic |-Path redundancy | | |||
|Mechanisms | delay |-Control message | | |Mechanisms | delay |-Control message | | |||
| |-Increased resource | protection | | | |-Increased resource | protection | | |||
| | consumption |-Performance | | | | consumption |-Performance | | |||
| |-Data disruption | analytics | | | |-Data disruption | analytics | | |||
+----------------------+---------------------+---------------------+ | +----------------------+---------------------+---------------------+ | |||
Figure 3: Mapping Attacks to Impact and Mitigations | Figure 3: Mapping Attacks to Impact and Mitigations | |||
6. Association of Attacks to Use Cases | 6. Association of Attacks to Use Cases | |||
6.1. Use Cases by Common Themes | ||||
Different attacks can have different impact and/or mitigation | Different attacks can have different impact and/or mitigation | |||
depending on the use case, so we would like to make this association | depending on the use case, so we would like to make this association | |||
in our analysis. However since there is a potentially unbounded list | in our analysis. However since there is a potentially unbounded list | |||
of use cases, we categorize the attacks with respect to the common | of use cases, we categorize the attacks with respect to the common | |||
themes of the use cases as identified in the Use Case Common Themes | themes of the use cases as identified in the Use Case Common Themes | |||
section of the DetNet Use Cases draft [I-D.ietf-detnet-use-cases]. | section of the DetNet Use Cases draft [I-D.ietf-detnet-use-cases]. | |||
We describe each theme and its associated attacks, impacts and | ||||
mitigations. | See also Figure 2 for a mapping of the impact of attacks per use case | |||
by industry. | ||||
6.1. Use Cases by Common Themes | ||||
In this section we review each theme and discuss the attacks that are | ||||
applicable to that theme, as well as anything specific about the | ||||
impact and mitigations for that attack with respect to that theme. | ||||
The table Figure 5 then provides a summary of the attacks that are | ||||
applicable to each theme. | ||||
6.1.1. Network Layer - AVB/TSN Ethernet | 6.1.1. Network Layer - AVB/TSN Ethernet | |||
Presumably it will be possible to run DetNet over other underlying | DetNet is expected to run over various transmission mediums, with | |||
network layers besides Ethernet, but Ethernet is explicitly | Ethernet being explicitly supported. Attacks such as Delay or | |||
supported. Is the attack specific to the Ethernet AVB/TSN protocols? | Reconnaissance might be implemented differently on a different | |||
Does the threat affect only Ethernet, or any underlying network | transmission medium, however the impact on the DetNet as a whole | |||
layer? | would be essentially the same. We thus conclude that all attacks and | |||
impacts that would be applicable to DetNet over Ethernet (i.e. all | ||||
those named in this draft) would also be applicable to DetNet over | ||||
other transmission mediums. | ||||
With respect to mitigations, some methods are specific to the | ||||
Ethernet medium, for example time-aware scheduling using 802.1Qbv can | ||||
protect against excessive use of bandwidth at the ingress - for other | ||||
mediums, other mitigations would have to be implemented to provide | ||||
analogous protection. | ||||
6.1.2. Central Administration | 6.1.2. Central Administration | |||
A DetNet network is expected to be controlled by a centralized | A DetNet network is expected to be controlled by a centralized | |||
network configuration and control system. Such a system may be in a | network configuration and control system (CNC). Such a system may be | |||
single central location, or it may be distributed across multiple | in a single central location, or it may be distributed across | |||
control entities that function together as a unified control system | multiple control entities that function together as a unified control | |||
for the network. Is the attack directed at threat the central | system for the network. | |||
control system of the network? Does it interfere with OAM? | ||||
In this draft we distinguish between attacks on the DetNet Control | ||||
plane vs. Data plane. But is an attack affecting control plane | ||||
packets synonymous with an attack on the CNC itself? For purposes of | ||||
this draft let us consider an attack on the CNC itself to be out of | ||||
scope, and consider all attacks named in this draft which are | ||||
relevant to control plane packets to be relevant to this theme, | ||||
including Path Manipulation, Path Choice, Control Packet Modification | ||||
or Injection, Reconaissance and Attacks on Time Sync Mechanisms. | ||||
6.1.3. Hot Swap | 6.1.3. Hot Swap | |||
A DetNet network is not expected to be "plug and play" - it is | A DetNet network is not expected to be "plug and play" - it is | |||
expected that there is some centralized network configuration and | expected that there is some centralized network configuration and | |||
control system. However, the ability to "hot swap" components (e.g. | control system. However, the ability to "hot swap" components (e.g. | |||
due to malfunction) is similar enough to "plug and play" that this | due to malfunction) is similar enough to "plug and play" that this | |||
kind of behavior may be expected in DetNet networks, depending on the | kind of behavior may be expected in DetNet networks, depending on the | |||
implementation. Does the attack target "hot swap" ("plug and play") | implementation. | |||
operation in the network? | ||||
An attack surface related to Hot Swap is that the DetNet network must | ||||
at least consider input at runtime from devices that were not part of | ||||
the initial configuration of the network. Even a "perfect" (or | ||||
"hitless") replacement of a device at runtime would not necessarily | ||||
be ideal, since presumably one would want to distinguish it from the | ||||
original for OAM purposes (e.g. to report hot swap of a failed | ||||
device). | ||||
This implies that an attack such as Flow Modification, Spoofing or | ||||
Inter-segment (which could introduce packets from a "new" device | ||||
(i.e. one heretofore unknown on the network) could be used to exploit | ||||
the need to consider such packets (as opposed to rejecting them out | ||||
of hand as one would do if one did not have to consider introduction | ||||
of a new device). | ||||
Similarly if the network was designed to support runtime replacement | ||||
of a clock device, then presence (or apparent presence) and thus | ||||
consideration of packets from a new such device could affect the | ||||
network, or the time sync of the network, for example by initiating a | ||||
new Best Master Clock selection process. Thus attacks on time sync | ||||
should be considered when designing hot swap type functionality. | ||||
6.1.4. Data Flow Information Models | 6.1.4. Data Flow Information Models | |||
Data Flow Information Models specific to DetNet networks are to be | Data Flow Information Models specific to DetNet networks are to be | |||
specified by DetNet. Thus they are "new" and thus potentially | specified by DetNet. Thus they are "new" and thus potentially | |||
present a new attack surface. Does the threat take advantage of any | present a new attack surface. Does the threat take advantage of any | |||
aspect of our new Data Flow Info Models? | aspect of our new Data Flow Info Models? | |||
This is TBD, thus there are no specific entries in our table, however | ||||
that does not imply that there could be no relevant attacks. | ||||
6.1.5. L2 and L3 Integration | 6.1.5. L2 and L3 Integration | |||
A DetNet network is intended to integrate between Layer 2 (bridged) | A DetNet network integrates Layer 2 (bridged) networks (e.g. AVB/TSN | |||
network(s) (e.g. AVB/TSN LAN) and Layer 3 (routed) network(s) (e.g. | LAN) and Layer 3 (routed) networks via the use of well-known | |||
using IP-based protocols). Does the attack target L2? L3? Both? | protocols such as IPv6, MPLS-PW, and Ethernet. Presumably security | |||
The interaction between the two? | considerations applicable directly to those individual protocols is | |||
not specific to DetNet, and thus out of scope for this draft. | ||||
However enabling DetNet to coordinate Layer 2 and Layer 3 behavior | ||||
will require some additions to existing protocols (see draft-dt- | ||||
detnet-dp-alt) and any such new work can introduce new attack | ||||
surfaces. | ||||
This is TBD, thus there are no specific entries in our table, however | ||||
that does not imply that there could be no relevant attacks. | ||||
6.1.6. End-to-End Delivery | 6.1.6. End-to-End Delivery | |||
Packets sent over DetNet are guaranteed not to be dropped by the | Packets sent over DetNet are guaranteed not to be dropped by the | |||
network due to congestion. (Packets may however be dropped for | network due to congestion. (Packets may however be dropped for | |||
intended reasons, e.g. per security measures). Does the attack | intended reasons, e.g. per security measures). | |||
result in packets (which should be delivered) not being delivered? | ||||
Does it result in packets that should not be delivered being | A Data plane attack may force packets to be dropped, for example a | |||
delivered? | "long" Delay or Replication/Elimination or Flow Modification attack. | |||
The same result might be obtained by a Control plane attack, e.g. | ||||
Path Manipulation or Signaling Packet Modification. | ||||
It may be that such attacks are limited to Internal MITM attackers, | ||||
but other possibilities should be considered. | ||||
An attack may also cause packets that should not be delivered to be | ||||
delivered, such as by forcing packets from one (e.g. replicated) path | ||||
to be preferred over another path when they should not be | ||||
(Replication attack), or by Flow Modification, or by Path Choice or | ||||
Packet Injection. A Time Sync attack could cause a system that was | ||||
expecting certain packets at certain times to accept unintended | ||||
packets based on compromised system time or time windowing in the | ||||
scheduler. | ||||
6.1.7. Proprietary Deterministic Ethernet Networks | 6.1.7. Proprietary Deterministic Ethernet Networks | |||
There are many proprietary non-interoperable deterministic Ethernet- | There are many proprietary non-interoperable deterministic Ethernet- | |||
based networks currently available; DetNet is intended to provide an | based networks currently available; DetNet is intended to provide an | |||
open-standards-based alternative to such networks. Does the threat | open-standards-based alternative to such networks. In cases where a | |||
relate to a specific such network that is being "emulated" or | DetNet intersects with remnants of such networks or their protocols, | |||
"replaced" by DetNet, for example by exploiting specific commands | such as by protocol emulation or access to such a network via a | |||
specific to that network protocol? | gateway, new attack surfaces can be opened. | |||
For example an Inter-Segment or Control plane attack such as Path | ||||
Manipulation, Path Choice or Control Packet Modification/Injection | ||||
could be used to exploit commands specific to such a protocol, or | ||||
that are interpreted differently by the different protocols or | ||||
gateway. | ||||
6.1.8. Replacement for Proprietary Fieldbuses | 6.1.8. Replacement for Proprietary Fieldbuses | |||
There are many proprietary "field buses" used in today's industrial | There are many proprietary "field buses" used in today's industrial | |||
and other industries; DetNet is intended to provide an open- | and other industries; DetNet is intended to provide an open- | |||
standards-based alternative to such buses. Does the threat relate to | standards-based alternative to such buses. In cases where a DetNet | |||
a specific fieldbus that is being "emulated" or "replaced" by DetNet, | intersects with such fieldbuses or their protocols, such as by | |||
for example by exploiting specific commands specific to that network | protocol emulation or access via a gateway, new attack surfaces can | |||
protocol? | be opened. | |||
For example an Inter-Segment or Control plane attack such as Path | ||||
Manipulation, Path Choice or Control Packet Modification/Injection | ||||
could be used to exploit commands specific to such a protocol, or | ||||
that are interpreted differently by the different protocols or | ||||
gateway. | ||||
6.1.9. Deterministic vs Best-Effort Traffic | 6.1.9. Deterministic vs Best-Effort Traffic | |||
DetNet is intended to support coexistence of time-sensitive | DetNet is intended to support coexistence of time-sensitive | |||
operational (OT, deterministic) traffic and information (IT, "best | operational (OT, deterministic) traffic and information (IT, "best | |||
effort") traffic on the same ("unified") network. Does the attack | effort") traffic on the same ("unified") network. | |||
affect only IT or only OT or both types of traffic? Does the threat | ||||
affect any interaction between IT and OT traffic, e.g. by changing | The presence of IT traffic on a network carrying OT traffic has long | |||
relative priority or handling of IT vs. OT packets? | been considered insecure design [reference needed here]. With | |||
DetNet, this coexistance will become more common, and mitigations | ||||
will need to be established. The fact that the IT traffic on a | ||||
DetNet is limited to a corporate controlled network makes this a less | ||||
difficult problem compared to being exposed to the open Internet, | ||||
however this aspect of DetNet security should not be underestimated. | ||||
Most of the themes described in this draft address OT (reserved) | ||||
streams - this item is intended to address issues related to IT | ||||
traffic on a DetNet. | ||||
An Inter-segment attack can flood the network with IT-type traffic | ||||
with the intent of disrupting handling of IT traffic, and/or the goal | ||||
of interfering with OT traffic. Presumably if the stream reservation | ||||
and isolation of the DetNet is well-designed (better-designed than | ||||
the attack) then interference with OT traffic should not result from | ||||
an attack that floods the network with IT traffic. | ||||
However the DetNet's handling of IT traffic may not (by design) be as | ||||
resilient to DOS attack, and thus designers must be otherwise | ||||
prepared to mitigate DOS attacks on IT traffic in a DetNet. | ||||
6.1.10. Deterministic Flows | 6.1.10. Deterministic Flows | |||
Reserved bandwidth data flows (deterministic flows) must be isolated | Reserved bandwidth data flows (deterministic flows) must provide the | |||
from each other and from best-effort traffic, so that even if the | allocated bandwidth, and must be isolated from each other. | |||
network is saturated with best-effort and/or reserved bandwidth | ||||
traffic the configured flows are not adversely affected. Does the | A Spoofing or Inter-segment attack which adds packet traffic to a | |||
attack affect the isolation of one (reserved) flow from another? | bandwidth-reserved stream could cause that stream to occupy more | |||
bandwidth than it is allocated, resulting in interference with other | ||||
deterministic flows. | ||||
A Flow Modification or Spoofing or Header Manipulation or Control | ||||
Packet Modification attack could cause packets from one flow to be | ||||
directed to another flow, thus breaching isolation between the flows. | ||||
6.1.11. Unused Reserved Bandwidth | 6.1.11. Unused Reserved Bandwidth | |||
If bandwidth reservations are made for a stream but the associated | If bandwidth reservations are made for a stream but the associated | |||
bandwidth is not used at any point in time, that bandwidth is made | bandwidth is not used at any point in time, that bandwidth is made | |||
available on the network for best-effort traffic. If the owner of | available on the network for best-effort traffic. If the owner of | |||
the reserved stream then starts transmitting again, the bandwidth is | the reserved stream then starts transmitting again, the bandwidth is | |||
no longer available for best-effort traffic, on a moment-to-moment | no longer available for best-effort traffic, on a moment-to-moment | |||
basis. (Such "temporarily available" bandwidth is not available for | basis. (Such "temporarily available" bandwidth is not available for | |||
time-sensitive traffic, which must have its own reservation). Does | time-sensitive traffic, which must have its own reservation). | |||
the attack affect the system's ability to allocate unused reserved BW | ||||
to best-effort traffic? | An Inter-segment attack could flood the network with IT traffic, | |||
interfering with the intended IT traffic. | ||||
A Flow Modification or Spoofing or Control Packet Modification or | ||||
Injection attack could cause extra bandwidth to be reserved by a new | ||||
or existing stream, thus making it unavailable for use by best-effort | ||||
traffic. | ||||
6.1.12. Interoperability | 6.1.12. Interoperability | |||
The DetNet network specifications are intended to enable an ecosystem | The DetNet network specifications are intended to enable an ecosystem | |||
in which multiple vendors can create interoperable products, thus | in which multiple vendors can create interoperable products, thus | |||
promoting device diversity and potentially higher numbers of each | promoting device diversity and potentially higher numbers of each | |||
device manufactured. Does the threat take advantage of differences | device manufactured. Does the threat take advantage of differences | |||
in implementation of "interoperable" products made by different | in implementation of "interoperable" products made by different | |||
vendors? | vendors? | |||
This is TBD, thus there are no specific entries in our table, however | ||||
that does not imply that there could be no relevant attacks. | ||||
6.1.13. Cost Reductions | 6.1.13. Cost Reductions | |||
The DetNet network specifications are intended to enable an ecosystem | The DetNet network specifications are intended to enable an ecosystem | |||
in which multiple vendors can create interoperable products, thus | in which multiple vendors can create interoperable products, thus | |||
promoting higher numbers of each device manufactured, promoting cost | promoting higher numbers of each device manufactured, promoting cost | |||
reduction and cost competition among vendors. Does the threat take | reduction and cost competition among vendors. Does the threat take | |||
advantage of "low cost" HW or SW components or other "cost-related | advantage of "low cost" HW or SW components or other "cost-related | |||
shortcuts" that might be present in devices? | shortcuts" that might be present in devices? | |||
This is TBD, thus there are no specific entries in our table, however | ||||
that does not imply that there could be no relevant attacks. | ||||
6.1.14. Insufficiently Secure Devices | 6.1.14. Insufficiently Secure Devices | |||
The DetNet network specifications are intended to enable an ecosystem | The DetNet network specifications are intended to enable an ecosystem | |||
in which multiple vendors can create interoperable products, thus | in which multiple vendors can create interoperable products, thus | |||
promoting device diversity and potentially higher numbers of each | promoting device diversity and potentially higher numbers of each | |||
device manufactured. Does the threat attack "naivete" of SW, for | device manufactured. Does the threat attack "naivete" of SW, for | |||
example SW that was not designed to be sufficiently secure (or secure | example SW that was not designed to be sufficiently secure (or secure | |||
at all) but is deployed on a DetNet network that is intended to be | at all) but is deployed on a DetNet network that is intended to be | |||
highly secure? (For example IoT exploits like the Mirai video-camera | highly secure? (For example IoT exploits like the Mirai video-camera | |||
botnet ([MIRAI]). | botnet ([MIRAI]). | |||
This is TBD, thus there are no specific entries in our table, however | ||||
that does not imply that there could be no relevant attacks. | ||||
6.1.15. DetNet Network Size | 6.1.15. DetNet Network Size | |||
DetNet networks range in size from very small, e.g. inside a single | DetNet networks range in size from very small, e.g. inside a single | |||
industrial machine, to very large, for example a Utility Grid network | industrial machine, to very large, for example a Utility Grid network | |||
spanning a whole country, and involving many "hops" over various | spanning a whole country. | |||
kinds of links for example radio repeaters, microwave links, fiber | ||||
optic links, etc.. Does the attack affect DetNet networks of only | The size of the network might be related to how the attack is | |||
certain sizes, e.g. very large networks, or very small? This might | introduced into the network, for example if the entire network is | |||
be related to how the attack is introduced into the network, for | local, there is a threat that power can be cut to the entire network. | |||
example if the entire network is local, there is a threat that power | If the network is large, perhaps only a part of the network is | |||
can be cut to the entire network. If the network is large, perhaps | attacked. | |||
only a part of the network is attacked. Does the threat take | ||||
advantage of attack vectors that are specific to network size? | A Delay attack might be as relevant to a small network as to a large | |||
network, although the amount of delay might be different. | ||||
Attacks sourced from IT traffic might be more likely in large | ||||
networks, since more people might have access to the network. | ||||
Similarly Path Manipulation, Path Choice and Time Sync attacks seem | ||||
more likely relevant to large networks. | ||||
6.1.16. Multiple Hops | 6.1.16. Multiple Hops | |||
DetNet networks range in size from very small, e.g. inside a single | Large DetNet networks (e.g. a Utility Grid network) may involve many | |||
industrial machine, to very large, for example a Utility Grid network | "hops" over various kinds of links for example radio repeaters, | |||
spanning a whole country, and involving many "hops" over various | microwave links, fiber optic links, etc.. | |||
kinds of links for example radio repeaters, microwave links, fiber | ||||
optic links, etc.. Does the attack exploit the presence of more than | An attack that takes advantage of flaws (or even normal operation) in | |||
one "hop"? Does the threat exploit the presence of more than one | the device drivers for the various links (through internal knowledge | |||
type of "hop", e.g. between radio and microwave links? Does the | of how the individual driver or firmware operates, perhaps like the | |||
threat exploit a specific type of "hop", e.g. something specific to | Stuxnet attack) could take proportionately greater advantage of this | |||
a fiber optic link, or other type of link? | topology. We don't currently have an attack like this defined; we | |||
have only "protocol" (time or packet) based attacks. Perhaps we need | ||||
to define an attack like this? Or is that out of scope for DetNet? | ||||
It is also possible that this DetNet topology will not be in as | ||||
common use as other more homogeneous topologies so there may be more | ||||
opportunity for attackers to exploit software and/or protocol flaws | ||||
in the implementations which have not been wrung out by extensive | ||||
use, particularly in the case of early adopters. | ||||
Of the attacks we have defined, the ones identified above as relevant | ||||
to "large" networks seem to be most relevant. | ||||
6.1.17. Level of Service | 6.1.17. Level of Service | |||
A DetNet is expected to provide means to configure the network that | A DetNet is expected to provide means to configure the network that | |||
include querying network path latency, requesting bounded latency for | include querying network path latency, requesting bounded latency for | |||
a given stream, requesting worst case maximum and/or minimum latency | a given stream, requesting worst case maximum and/or minimum latency | |||
for a given path or stream, and so on. It is an expected case that | for a given path or stream, and so on. It is an expected case that | |||
the network cannot provide a given requested service level. In such | the network cannot provide a given requested service level. In such | |||
cases the network control system should reply that the requested | cases the network control system should reply that the requested | |||
service level is not available (as opposed to accepting the parameter | service level is not available (as opposed to accepting the parameter | |||
but then not delivering the desired behavior). Does the attack | but then not delivering the desired behavior). | |||
affect any querying or replying to such service-level-related | ||||
traffic? Can the attack cause incorrect responses from the system | Control plane attacks such as Signaling Packet Modification and | |||
regarding timing-related configuration? For example replying that a | Injection could be used to modify or create control traffic that | |||
requested level of service is available when it isn't, or that the | could interfere with the process of a user requesting a level of | |||
requested level of service is not available when it actually is | service and/or the network's reply. | |||
available? | ||||
Reconnaissance could be used to characterize flows and perhaps target | ||||
specific flows for attack via the Control plane as noted above. | ||||
6.1.18. Bounded Latency | 6.1.18. Bounded Latency | |||
Does the threat affect the network's ability to deliver packets | DetNet provides the expectation of guaranteed bounded latency. | |||
within the agreed-upon latency boundaries? | ||||
Delay attacks can cause packets to miss their agreed-upon latency | ||||
boundaries. | ||||
Time Sync attacks can corrupt the system's time reference, resulting | ||||
in missed latency deadlines (with respect to the "correct" time | ||||
reference). | ||||
6.1.19. Low Latency | 6.1.19. Low Latency | |||
Applications may require "extremely low latency" however depending on | Applications may require "extremely low latency" however depending on | |||
the application these may mean very different latency values; for | the application these may mean very different latency values; for | |||
example "low latency" across a Utility grid network is on a different | example "low latency" across a Utility grid network is on a different | |||
time scale than "low latency" in a motor control loop in a small | time scale than "low latency" in a motor control loop in a small | |||
machine. The intent is that the mechanisms for specifying desired | machine. The intent is that the mechanisms for specifying desired | |||
latency include wide ranges, and that architecturally there is | latency include wide ranges, and that architecturally there is | |||
nothing to prevent arbitrarily low latencies from being implemented | nothing to prevent arbitrarily low latencies from being implemented | |||
in a given network. Does the threat affect the network's ability to | in a given network. | |||
deliver packets within the agreed-upon low latency? | ||||
Attacks on the Control plane (as described in the Level of Service | ||||
theme) and Delay and Time attacks (as described in the Bounded | ||||
Latency theme) both apply here. | ||||
6.1.20. Symmetrical Path Delays | 6.1.20. Symmetrical Path Delays | |||
Some applications would like to specify that the transit delay time | Some applications would like to specify that the transit delay time | |||
values be equal for both the transmit and return paths. Does the | values be equal for both the transmit and return paths. | |||
attack affect the network's ability to provide matched transmit and | ||||
return path delays (latencies)? | Delay attacks can cause path delays to differ. | |||
Time Sync attacks can corrupt the system's time reference, resulting | ||||
in differing path delays (with respect to the "correct" time | ||||
reference). | ||||
6.1.21. Reliability and Availability | 6.1.21. Reliability and Availability | |||
DetNet based systems are expected to be implemented with essentially | DetNet based systems are expected to be implemented with essentially | |||
arbitrarily high availability (for example 99.9999% up time, or even | arbitrarily high availability (for example 99.9999% up time, or even | |||
12 nines). The intent is that the DetNet designs should not make any | 12 nines). The intent is that the DetNet designs should not make any | |||
assumptions about the level of reliability and availability that may | assumptions about the level of reliability and availability that may | |||
be required of a given system, and should define parameters for | be required of a given system, and should define parameters for | |||
communicating these kinds of metrics within the network. Does the | communicating these kinds of metrics within the network. | |||
attack affect the reliability of the DetNet network? Is it a large | ||||
or small change, e.g. the difference between completely taking down | Any attack on the system, of any type, can affect its overall | |||
the network for some period of time, vs reducing its reliability by | reliability and availability, thus in our table we have marked every | |||
just one "nine"? Does the threat affect the availability of the | attack. Since every DetNet depends to a greater or lesser degree on | |||
DetNet network? | reliability and availability, this essentially means that all | |||
networks have to mitigate all attacks, which to a greater or lesser | ||||
degree defeats the purpose of associating attacks with use cases. It | ||||
also underscores the difficulty of designing "extremely high | ||||
reliability" networks. I hope that in future drafts we can say | ||||
something more useful here. | ||||
6.1.22. Redundant Paths | 6.1.22. Redundant Paths | |||
DetNet based systems are expected to be implemented with essentially | DetNet based systems are expected to be implemented with essentially | |||
arbitrarily high reliability/availability. A strategy used by DetNet | arbitrarily high reliability/availability. A strategy used by DetNet | |||
for providing such extraordinarily high levels of reliability is to | for providing such extraordinarily high levels of reliability is to | |||
provide redundant paths that can be seamlessly switched between, all | provide redundant paths that can be seamlessly switched between, all | |||
the while maintaining the required performance of that system. Does | the while maintaining the required performance of that system. | |||
the attack affect the configuration or operation of redundant paths? | ||||
Replication-related attacks are by definition applicable here. | ||||
Control plane attacks can also interfere with the configuration of | ||||
redundant paths. | ||||
6.1.23. Security Measures | 6.1.23. Security Measures | |||
A DetNet network must be made secure against devices failures, | A DetNet network must be made secure against devices failures, | |||
attackers, misbehaving devices, and so on. Does the threat affect | attackers, misbehaving devices, and so on. Does the threat affect | |||
such security measures themselves, e.g. by attacking SW designed to | such security measures themselves, e.g. by attacking SW designed to | |||
protect against device failure? | protect against device failure? | |||
This is TBD, thus there are no specific entries in our table, however | ||||
that does not imply that there could be no relevant attacks. | ||||
6.2. Attack Types by Use Case Common Theme | 6.2. Attack Types by Use Case Common Theme | |||
The following table lists the attacks of Section 3, assigning a | The following table lists the attacks of Section 3, assigning a | |||
number to each type of attack. That number is then used as a short | number to each type of attack. That number is then used as a short | |||
form identifier for the attack in Figure 5. | form identifier for the attack in Figure 5. | |||
+--+----------------------------------------+----------------------+ | +--+----------------------------------------+----------------------+ | |||
| | Attack | Section | | | | Attack | Section | | |||
+--+----------------------------------------+----------------------+ | +--+----------------------------------------+----------------------+ | |||
| 1|Delay Attack | Section 3.2.1 | | | 1|Delay Attack | Section 3.2.1 | | |||
skipping to change at page 25, line 50 ¶ | skipping to change at page 29, line 50 ¶ | |||
| | 1| 2| 3| 4| 5| 6| 7| 8| 9|10|11| | | | 1| 2| 3| 4| 5| 6| 7| 8| 9|10|11| | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Network Layer - AVB/TSN Eth.| +| +| +| +| +| +| +| +| +| +| +| | |Network Layer - AVB/TSN Eth.| +| +| +| +| +| +| +| +| +| +| +| | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Central Administration | | | | | | +| +| +| +| +| +| | |Central Administration | | | | | | +| +| +| +| +| +| | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Hot Swap | | +| +| | | | | | | | +| | |Hot Swap | | +| +| | | | | | | | +| | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Data Flow Information Models| | | | | | | | | | | | | |Data Flow Information Models| | | | | | | | | | | | | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|L2 and L3 Integration | | | | | +| +| | | | | | | |L2 and L3 Integration | | | | | | | | | | | | | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|End-to-end Delivery | | | | +| +| | | | | | | | |End-to-end Delivery | +| +| +| +| +| +| +| +| +| | +| | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Proprietary Deterministic | | | +| | | +| +| +| +| | | | |Proprietary Deterministic | | | +| | | +| +| +| +| | | | |||
|Ethernet Networks | | | | | | | | | | | | | |Ethernet Networks | | | | | | | | | | | | | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Replacement for Proprietary | | | +| | | +| +| +| +| | | | |Replacement for Proprietary | | | +| | | +| +| +| +| | | | |||
|Fieldbuses | | | | | | | | | | | | | |Fieldbuses | | | | | | | | | | | | | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Deterministic vs. Best- | | | +| | | | | | | | | | |Deterministic vs. Best- | | | +| | | | | | | | | | |||
|Effort Traffic | | | | | | | | | | | | | |Effort Traffic | | | | | | | | | | | | | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Deterministic Flows | | | +| | | | | | | | | | |Deterministic Flows | | +| +| | +| +| | +| | | | | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Unused Reserved Bandwidth | | | +| | | | | | | | | | |Unused Reserved Bandwidth | | +| +| | | | | +| +| | | | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Interoperability | | | | | | | | | | | | | |Interoperability | | | | | | | | | | | | | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Cost Reductions | | | | | | | | | | | | | |Cost Reductions | | | | | | | | | | | | | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Insufficiently Secure | | | | | | | | | | | | | |Insufficiently Secure | | | | | | | | | | | | | |||
|Devices | | | | | | | | | | | | | |Devices | | | | | | | | | | | | | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|DetNet Network Size | +| | | | | +| +| | | | +| | |DetNet Network Size | +| | | | | +| +| | | | +| | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Multiple Hops | +| +| | | | +| +| | | | +| | |Multiple Hops | +| +| | | | +| +| | | | +| | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Level of Service | | | | | | | | +| +| +| | | |Level of Service | | | | | | | | +| +| +| | | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Bounded Latency | +| | | | | | | | | | +| | |Bounded Latency | +| | | | | | | | | | +| | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Low Latency | +| | | | | | | | | | +| | |Low Latency | +| | | | | | | +| +| +| +| | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Symmetric Path Delays | +| | | | | | | | | | +| | |Symmetric Path Delays | +| | | | | | | | | | +| | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Reliability and Availability| +| +| +| +| +| +| +| +| +| +| +| | |Reliability and Availability| +| +| +| +| +| +| +| +| +| +| +| | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Redundant Paths | | | | +| +| | | +| +| | | | |Redundant Paths | | | | +| +| | | +| +| | | | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
|Security Measures | | | | | | | | | | | | | |Security Measures | | | | | | | | | | | | | |||
+----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | +----------------------------+--+--+--+--+--+--+--+--+--+--+--+ | |||
skipping to change at page 33, line 42 ¶ | skipping to change at page 37, line 42 ¶ | |||
[I-D.ietf-detnet-architecture] | [I-D.ietf-detnet-architecture] | |||
Finn, N., Thubert, P., Varga, B., and J. Farkas, | Finn, N., Thubert, P., Varga, B., and J. Farkas, | |||
"Deterministic Networking Architecture", draft-ietf- | "Deterministic Networking Architecture", draft-ietf- | |||
detnet-architecture-03 (work in progress), August 2017. | detnet-architecture-03 (work in progress), August 2017. | |||
[I-D.ietf-detnet-use-cases] | [I-D.ietf-detnet-use-cases] | |||
Grossman, E., Gunther, C., Thubert, P., Wetterwald, P., | Grossman, E., Gunther, C., Thubert, P., Wetterwald, P., | |||
Raymond, J., Korhonen, J., Kaneko, Y., Das, S., Zha, Y., | Raymond, J., Korhonen, J., Kaneko, Y., Das, S., Zha, Y., | |||
Varga, B., Farkas, J., Goetz, F., Schmitt, J., Vilajosana, | Varga, B., Farkas, J., Goetz, F., Schmitt, J., Vilajosana, | |||
X., Mahmoodi, T., Spirou, S., and P. Vizarreta, | X., Mahmoodi, T., Spirou, S., Vizarreta, P., Huang, D., | |||
"Deterministic Networking Use Cases", draft-ietf-detnet- | Geng, X., Dujovne, D., and M. Seewald, "Deterministic | |||
use-cases-12 (work in progress), April 2017. | Networking Use Cases", draft-ietf-detnet-use-cases-13 | |||
(work in progress), September 2017. | ||||
[I-D.varga-detnet-service-model] | [I-D.varga-detnet-service-model] | |||
Varga, B. and J. Farkas, "DetNet Service Model", draft- | Varga, B. and J. Farkas, "DetNet Service Model", draft- | |||
varga-detnet-service-model-02 (work in progress), May | varga-detnet-service-model-02 (work in progress), May | |||
2017. | 2017. | |||
[IEEE1588] | [IEEE1588] | |||
IEEE, "IEEE 1588 Standard for a Precision Clock | IEEE, "IEEE 1588 Standard for a Precision Clock | |||
Synchronization Protocol for Networked Measurement and | Synchronization Protocol for Networked Measurement and | |||
Control Systems Version 2", 2008. | Control Systems Version 2", 2008. | |||
[MIRAI] krebsonsecurity.com, "https://krebsonsecurity.com/2016/10/ | [MIRAI] krebsonsecurity.com, "https://krebsonsecurity.com/2016/10/ | |||
hacked-cameras-dvrs-powered-todays-massive-internet- | hacked-cameras-dvrs-powered-todays-massive-internet- | |||
outage/", 2016. | outage/", 2016. | |||
[RFC3552] Rescorla, E. and B. Korver, "Guidelines for Writing RFC | ||||
Text on Security Considerations", BCP 72, RFC 3552, | ||||
DOI 10.17487/RFC3552, July 2003, | ||||
<https://www.rfc-editor.org/info/rfc3552>. | ||||
[RFC7384] Mizrahi, T., "Security Requirements of Time Protocols in | [RFC7384] Mizrahi, T., "Security Requirements of Time Protocols in | |||
Packet Switched Networks", RFC 7384, DOI 10.17487/RFC7384, | Packet Switched Networks", RFC 7384, DOI 10.17487/RFC7384, | |||
October 2014, <https://www.rfc-editor.org/info/rfc7384>. | October 2014, <https://www.rfc-editor.org/info/rfc7384>. | |||
Authors' Addresses | Authors' Addresses | |||
Tal Mizrahi | Tal Mizrahi | |||
Marvell | Marvell | |||
Email: talmi@marvell.com | Email: talmi@marvell.com | |||
End of changes. 80 change blocks. | ||||
327 lines changed or deleted | 571 lines changed or added | |||
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