Cyber Security: Autosar Secure Onboard Communication (SecOC)

Overview:

In today's automotive landscape, cybersecurity is paramount, especially with the increasing connectivity and complexity of modern vehicles. The Autosar Secure Onboard Communication (SecOC) module addresses this need by providing functionality to verify the authenticity and freshness of communication between Electronic Control Units (ECUs) within the vehicle architecture.

At Nav Tech Electronics, we understand the critical importance of cybersecurity in automotive systems. Our SecOC solutions are designed to ensure that communication between ECUs is secure, reliable, and protected against unauthorized manipulation and replay attacks.

Acronyms and Abbreviations:

Before delving deeper into SecOC, let's clarify some key terms:

• Authentic I-PDU: Refers to an Autosar I-PDU that requires protection against unauthorized manipulation and replay attacks.
• Secured I-PDU: Consists of the Authentic I-PDU and an Authenticator, such as a Message Authentication Code (MAC), to ensure data integrity and authenticity.
• Authenticator: A unique authentication data string generated using a Key, Data Identifier of the Secured I-PDU, Authentic Payload, and Freshness Value, providing confidence in the legitimacy of the data.

Authentic I-PDU and Secured I-PDU

The term Authentic I-PDU refers to an AUTOSAR I-PDU that requires protection against unauthorized manipulation and replay attacks.

The payload of a Secured I-PDU consists of the Authentic I-PDU and an Authenticator (e.g. Message Authentication Code). The payload of a Secured I-PDU may optionally include the Freshness Value used to create the Authenticator (e.g. MAC). The order in which the contents are structured in the Secured I-PDU is compliant with below Figure.

The length of the Authentic I-PDU, the Freshness Value and the Authenticator within a Secured I-PDU may vary from one uniquely indefinable Secured I-PDU to another.

The Authenticator (e.g. MAC) refers to a unique authentication data string generated using a Key, Data Identifier of the Secured I-PDU, Authentic Payload, and Freshness Value. The Authenticator provides a high level of confidence that the data in an Authentic I-PDU is generated by a legitimate source and is provided to the receiving ECU at the time in which it is intended for.

Supported SecOC Features:

Nav Tech's SecOC solutions offer a range of features to enhance cybersecurity in automotive systems:

1. Communication Flexibility: SECOC supports various communication methods like direct interface, transport protocol, or triggered transmission via CAN or FlexRay. Applications interact through modules like Com or Dcm.
2. Secured Data Handling: SECOC allows sending secured PDUs individually or as collections. It divides secured PDUs into authenticated and cryptographic parts, enhancing data security.
3. External Freshness Management: SECOC retrieves freshness values from external sources, either via software component or complex driver, ensuring data integrity.
4. Crypto Operation Configurability: Users can configure SECOC to perform cryptographic operations synchronously or asynchronously per PDU, such as MAC or signature generation/verification.
5. Fault Detection and Indication: SECOC detects and rejects faulty PDUs transparently. Callback functions notify applications of verification errors, including MAC generation failures.
6. Verification Override: Provides an interface to override PDU verification status, either passing or failing, influencing PDU handling based on verification outcome.
7. Fallback Mechanisms: SECOC includes features to send PDUs with default MAC or authentication information if generation fails, ensuring data transmission integrity.
8. Verification Control: Configurable option to skip PDU verification for specific scenarios, offering flexibility in data processing.
9. Selective Data Security: SECOC can secure either entire PDUs or specific areas within them, defined by offset and length, enhancing granularity in data protection.
10. PDU Layout Modification: Support for configuring callout functions to adjust the layout of secured PDUs, providing customization options for specific needs.

Use Case:

Let's consider a typical scenario where a vehicle's onboard communication is vulnerable to unauthorized manipulation. Nav Tech's SecOC module is integrated at the PDU router level on both sender and receiver sides to address this vulnerability.

When a message is sent on the bus, SecOC creates a secured I-PDU by appending a MAC with a freshness value to the authentic I-PDU. On the receiver side, SecOC verifies the authentication information using cryptographic services provided by the Crypto Security Module (Csm) before forwarding the I-PDU to the receiver.

Nav Tech's Contribution:

Nav Tech Electronics is at the forefront of automotive cybersecurity solutions. Our SecOC offerings provide robust protection against cyber threats, ensuring the integrity and authenticity of communication between ECUs. With Nav Tech, automotive manufacturers can trust that their vehicles are equipped with state-of-the-art cybersecurity measures, safeguarding against potential cyber attacks and ensuring passenger safety and data security.

In conclusion, Autosar Secure Onboard Communication (SecOC) plays a crucial role in enhancing cybersecurity in automotive systems, and Nav Tech's innovative solutions are paving the way for a safer and more secure automotive future.

Author: Chanamallappa Halli