1. SOS in OpenPGP

    I was not able to describe SOS itself accurately in ECC in OpenPGP by SOS.

    So, this article is to augument the explanation.

    SOS is a suggestion to OpenPGP implementations to address the zero removal/recovery problem. I know that implementations already handle it by adding zero recovary for Ed25519 …

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  2. ECC in OpenPGP by SOS

    In this article, I try to explain a specific way to improve current (as of March 2021) situation of OpenPGP with regards to EdDSA and ECDH with modern curves.

    Specifically, I suggest a way to introduce SOS. But even if you won't introduce SOS methodology into your implementation of OpenPGP …

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  3. Flash Memory Read-Out Protection

    MCU usually supports a feature to disable reading out its content of flash memory for external use.

    Such a feature is useful when we build a device like Gnuk Token, because we can make sure that secret data on a device cannot be read out.

    Historically, this feature was implemented …

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  4. Porting Chopstx to RISC-V MCU

    For GD32VF103 (Note: it's not GD32 F 103, but GD32 VF 103), I ported Chopstx in master. It will be released in Chopstx 2.0.

    It was in 2018, when I ported Chopstx to GD32F103 in Chopstx 1.9. GD32F103 uses ARM Cortex-M3 core and peripherals are compatible to STM32F103 …

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