OpenSSL & TLS

Certificates, TLS debugging, and encryption from the command line.

Generate Self-Signed Certificate

Quick (Dev/Local)

# One-liner: key + cert, valid 365 days
openssl req -x509 -newkey rsa:2048 -keyout key.pem -out cert.pem -days 365 -nodes \
  -subj "/CN=localhost"

# With SANs (needed for Chrome to accept it)
openssl req -x509 -newkey rsa:2048 -keyout key.pem -out cert.pem -days 365 -nodes \
  -subj "/CN=localhost" \
  -addext "subjectAltName=DNS:localhost,IP:127.0.0.1"