Depth Resolution: The central role of SSL certificates in HTTPS encryption

SSL (Secure Sockets Layer) certificate is a secure HTTPS Connected electronic vouchers. It ensures the confidentiality, integrity and authenticity of data transmitted between user browsers and servers through asymmetric encryption. A typical one. The X.509 format certificate contains a large amount of technical details, understanding which is essential to secure the website.

Key field resolution in SSL certificate

Common Name (CN)： certificate bound to the main domain name. For example: *.tools.kilocell.xyz 。 If the CN does not match the domain name that the user accesses, the browser will alert you about security warnings.
Subject Alternative Name (SAN)： Alternative name field. Modern certificates allow multiple domain names or IP addresses to be bound in one certificate, all listed in this field.
Fingerprint: The only HH value (usually SHA-256) for the certificate contents. to verify whether the certificate has been tampered with during the transfer.
Signature Algorithm： Signing algorithm. The main thing that's going on is that... sha256WithRSAEncryption or ecdsa-with-SHA256 。

How can the common problems of certification configuration and deployment be addressed?

Site one: Website tip "Certificate Expiry." Parsing your PEM file with this tool, checking Not After field. If the certificate does expire, you need to apply to an institution in CA (e.g. Let's Encrypt) for an extension and an update of the server configuration.

Scenario 2: Intermediate certificates are missing. Sometimes servers only deploy leaf certificates, which leads to some client tips that are “unsafe”. This tool helps you to confirm the chain of issuers of certificates, and thus to determine whether they need to be completed CA Certificate Chain (Bundle).

PEM Format Description

PEM (Privacy Enhanced Mail) is the most common storage format for SSL certificates. It's... -----BEGIN CERTIFICATE----- , and then -----END CERTIFICATE----- At the end, the middle part is binary data coded through Base64. This tool is available locally through JavaScript Decoding these data does not require uploading your sensitive certificates to any server.