zephyrproject-rtos/trusted-firmware-m
Feb 2025 – Mar 2025
2 Months active
Languages Used
CAssemblyCMake
Technical Skills
CryptographyDriver DevelopmentEmbedded SystemsHardware InteractionLow-Level ProgrammingSecurity
Amjad Ouled-Ameur
PROFILE
Amjad Ouled-ameur
Amjad Ouled-Ameur contributed to the zephyrproject-rtos/trusted-firmware-m repository by enhancing cryptographic robustness and hardware abstraction in embedded systems. He focused on the CC3XX driver, delivering improvements to the Deterministic Random Bit Generator, including AES external key loader integration and endian-safe operations. Using C and Assembly, Amjad addressed unaligned memory access, optimized HMAC lifecycle management, and implemented stack zeroization to prevent entropy leakage. He expanded test coverage for cryptographic primitives and automated test execution with build flags, strengthening reliability across Little and Big Endian platforms. His work demonstrated depth in low-level programming, security hardening, and rigorous test-driven development.
Overall Statistics
Feature vs Bugs
50%Features
Repository Contributions
27Total
Bugs
3
Commits
27
Features
3
Lines of code
695
Activity Months2
Your Network
573 peopleSame Organization
@arm.com498
Work History
March 2025
19 Commits • 3 Features
Mar 1, 2025In March 2025, delivered significant CC3XX-focused work in zephyrproject-rtos/trusted-firmware-m, improving cryptographic robustness, test automation, and security posture. Key features delivered and changes: - CC3XX DRBG core enhancements and fixes: AES external key loader integration; endian-safe DRBG CTR/HASH increments; addressed boundary and endianness issues. - CC3XX DRBG test coverage and infra: expanded DRBG tests (CTR, HASH, HMAC); added build flags to selectively enable tests; improved safeguards for DRBG test execution. - CC3XX security hardening and initialization: privileged AHB access configuration; relocation of SRAM encryption key setup to BL1_1; RNG robustness checks; cleanup and dead-code fixes to harden the stack against side-channel and fault risks. - CC3XX PKA tests: added tests for signed negative operands to validate handling of edge-case operands. Impact and business value: - Stronger cryptographic primitives with safer initialization and operation paths reduce risk of security vulnerabilities in trusted firmware. - More reliable, scalable testing with targeted build flags shortens CI cycles and accelerates validation of changes. - Improved hardware security posture (RNG robustness, side-channel mitigations) and clearer, auditable initialization flows support compliance and long-term maintainability. Technologies/skills demonstrated: - Embedded C, cryptographic primitives (CTR/HASH/HMAC, DRBG) and endianness handling; AES external key loader integration. - Test automation and CI optimization via build-flag-driven test suites; robust test infrastructure for cryptographic components. - Security hardening practices across BL1/BL1_1 layers, PKA integration, RNG checks, and DPA mitigation pathways.
19 Commits • 3 Features
Mar 1, 2025In March 2025, delivered significant CC3XX-focused work in zephyrproject-rtos/trusted-firmware-m, improving cryptographic robustness, test automation, and security posture. Key features delivered and changes: - CC3XX DRBG core enhancements and fixes: AES external key loader integration; endian-safe DRBG CTR/HASH increments; addressed boundary and endianness issues. - CC3XX DRBG test coverage and infra: expanded DRBG tests (CTR, HASH, HMAC); added build flags to selectively enable tests; improved safeguards for DRBG test execution. - CC3XX security hardening and initialization: privileged AHB access configuration; relocation of SRAM encryption key setup to BL1_1; RNG robustness checks; cleanup and dead-code fixes to harden the stack against side-channel and fault risks. - CC3XX PKA tests: added tests for signed negative operands to validate handling of edge-case operands. Impact and business value: - Stronger cryptographic primitives with safer initialization and operation paths reduce risk of security vulnerabilities in trusted firmware. - More reliable, scalable testing with targeted build flags shortens CI cycles and accelerates validation of changes. - Improved hardware security posture (RNG robustness, side-channel mitigations) and clearer, auditable initialization flows support compliance and long-term maintainability. Technologies/skills demonstrated: - Embedded C, cryptographic primitives (CTR/HASH/HMAC, DRBG) and endianness handling; AES external key loader integration. - Test automation and CI optimization via build-flag-driven test suites; robust test infrastructure for cryptographic components. - Security hardening practices across BL1/BL1_1 layers, PKA integration, RNG checks, and DPA mitigation pathways.
March 2025
February 2025
8 Commits
Feb 1, 2025February 2025 monthly summary for zephyrproject-rtos/trusted-firmware-m. Delivered security-focused robustness improvements to CC3XX cryptographic components and expanded low-level hardware abstraction support, with an emphasis on reliability, portability, and test coverage. Key changes include DRBG HASH hardening to correctly handle unaligned bytes, streamline HMAC lifecycle for long keys, and ensure alignment-safe memory access, alongside post-reseed entropy zeroization to prevent leakage. Also extended the PKA driver to support unaligned buffers for read/write operations and added tests to verify behavior on Little and Big Endian platforms.
February 2025
8 Commits
Feb 1, 2025February 2025 monthly summary for zephyrproject-rtos/trusted-firmware-m. Delivered security-focused robustness improvements to CC3XX cryptographic components and expanded low-level hardware abstraction support, with an emphasis on reliability, portability, and test coverage. Key changes include DRBG HASH hardening to correctly handle unaligned bytes, streamline HMAC lifecycle for long keys, and ensure alignment-safe memory access, alongside post-reseed entropy zeroization to prevent leakage. Also extended the PKA driver to support unaligned buffers for read/write operations and added tests to verify behavior on Little and Big Endian platforms.
Activity
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Quality Metrics
Correctness92.4%
Maintainability92.0%
Architecture91.2%
Performance88.2%
AI Usage20.0%
Skills & Technologies
Programming Languages
AssemblyCCMake
Technical Skills
Build SystemsC ProgrammingCompiler Behavior AnalysisCryptographic AlgorithmsCryptographic OperationsCryptographic TestingCryptographyDriver DevelopmentDriver TestingEmbedded SystemsFirmware DevelopmentHardware InteractionLow-Level ProgrammingLow-level Driver DevelopmentSecurity
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