Posts tagged "openssl"
How to Check If an RSA Cert Matches an RSA Key
Problem: you find a key and a cert file on your server, and want to check if the cert matches the key. Solution: Check the modulo (n=p*q) of both key and cert to see if they are equal. $ openssl rsa -modulus -noout -in yourrsa.key Modulus=C8BEE8B687CC... $ openssl x509 -modulus -noout -in yourrsa.crt Modulus=C8BEE8B...
Debian Curl/PHP/wget etc show an certificate error falsely
Problem: curl php wget and others show a cert error like the following since 6. Oct 2021, even though the cert has not expired: curl: (60) SSL certificate problem: certificate has expired More details here: https://curl.haxx.se/docs/sslcerts.html curl performs SSL certificate verification by default, using a "bundle...
Generate CSR using openssl
Browsers started to warn users about certificates with Sha1 signature. Sha256 is needed now a days. So it's time to renew certificates from Thawte, Godaddy, etc You can generate a new Certificate Signing Request with openssl with this command: openssl req -nodes -newkey rsa:2048 -keyout servername.key -out servernam...
Howto generate an SSL key and self signed cert with openssl
For SSH, HTTPS, TLS SMTP,POPS, IMAPS you need a RSA key pair. Most Linux package installers produce this pairs automatically, but if you like, you can generate them yourself. The quickest method I found is: openssl req -x509 -nodes -newkey rsa:2048 -keyout servername.key -out servername.crt -days 1024 This command a...