Difference between revisions of "cmd/openssl"

from HTYP, the free directory anyone can edit if they can prove to me that they're not a spambot
< cmd
Jump to navigation Jump to search
(improved formatting, and another command)
Line 25: Line 25:
 
==Links==
 
==Links==
 
* {{l/manpage}}
 
* {{l/manpage}}
 +
** [https://www.openssl.org/docs/manmaster/man5/config.html openssl.cnf]
 
* [http://www.openssl.org/ openssl.org]
 
* [http://www.openssl.org/ openssl.org]
 
** [http://www.openssl.org/docs/apps/s_client.html s_client]
 
** [http://www.openssl.org/docs/apps/s_client.html s_client]
 
* [http://www.madboa.com/geek/openssl/ examples]
 
* [http://www.madboa.com/geek/openssl/ examples]

Revision as of 14:44, 5 December 2020

About

openssl is the command-line program for managing SSL data and certificates.

Examples

  • To check that a certificate file is valid, and see what it says (does not work with key files) - typical file extensions are .crt, .ca:
    openssl x509 -text -in <filename>
  • To verify how a web server is presenting its certificate over https:
    openssl s_client -connect <domain>:443
    • To get the expiration date:
      echo | openssl s_client -connect <domain>:443 2>/dev/null | openssl x509 -noout -dates
  • To generate a new private key:
    openssl genrsa -des3 -out <filename.key> 4096
  • To remove the pass phrase from a private key:
    openssl rsa -in <oldfile.key> -out <newfile.key>
    There is slightly more explanation here.

Notes

  • openssl verify [1] seems to be the tool of choice for checking certificate files stored locally.
  • This also has some useful information about using openssl, and a little bit about the "chaining" concept.

Links