Posts in 2021

  • ECDSA signature verify in kotlin and Go

    January 16, 2021 in Security

    How to verify ECDSA signature generated by kotlin and verify it in Go?

    Introduction Elliptic Curve Digital Signature Algorithm (ECDSA) offers a variant of the Digital Signature Algorithm (DSA) which uses elliptic curve cryptography. ECDSA keys and signatures are shorter than in RSA for the same security level. A 256-bit …

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Posts in 2020

  • Test TLS Connectivity with OpenSSL Command Line

    December 13, 2020 in Security

    Use OpenSSL command line to test TLS server connectivity, check server certificate.

    Introduction openssl s_client is a SSL/TLS client program can be used to test TLS server connectivity, check server certificate. usage: s_client args -4 - Force IPv4 -6 - Force IPv6 -host host - use -connect instead -port port - use -connect instead …

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  • Running a DoH Client to encrypt all home DNS traffic

    March 06, 2020 in Security

    With DNS over HTTPS (Secure DNS), nobody listening on the wire can see the DNS queries you make when you are browsing the Internet.

    If you haven’t setup Secure DNS, do it today.

    What is Secure DNS Traditionally, DNS queries are sent in plaintext. Anyone listening on the Internet can see which websites you are connecting to. To ensure your DNS queries remain private, you should use a resolver that supports secure DNS …

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