OpenSSL Linux command line ssl tool
Links smtp , security/ssl , LinuxCurl, easy-rsa , LetsEncrypt
Online check cert + chain: https://tools.keycdn.com/ssl
Verify a web server certificate
openssl s_client -showcerts -connect my.test.com:443
- Output should end on "Verify return code: 0 (ok)"
- As of 2017 the TLS Protocol should be TLSv1.2 at least.
For sni you can add -servername xyz.test.com
Verifty a smtp server certificate
openssl s_client -starttls smtp -connect smtp.azurecomm.net:587 -servername smtp.azurecomm.net
OpenSSL retrieve url
retrieve url, e.g. /healthz, note -ign_eof to wait for more input from echo
time echo -e "GET /healthz HTTP/1.1\r\nConnection: close\r\nHost: pieter\r\n\r\n" |\ openssl s_client -ign_eof -connect 172.24.0.3:443
SSL speed testing
speed testing
openssl s_time -connect 172.17.0.2:443 -www "/welcome/" openssl s_time -connect 172.17.0.2:443 -www / curl -s -w 'Testing Website Response Time for :%{url_effective}\n\nLookup Time:\t\t%{time_namelookup}\nConnect Time:\t\t%{time_connect}\nPre-transfer Time:\t%{time_pretransfer}\nStart-transfer Time:\t%{time_starttransfer}\n\nTotal Time:\t\t%{time_total}\n' -o /dev/null https://172.17.0.2slow
231 connections in 0.29s; 796.55 connections/user sec, bytes read 57981 231 connections in 31 real seconds, 251 bytes read per connection
fast
30821 connections in 8.14s; 3786.36 connections/user sec, bytes read 6749799 30821 connections in 31 real seconds, 219 bytes read per connection
OpenSSL smtp certificate verify https://wiki.vigor.nz/linux/PostFixEmail
httping