Openssl

Links

• openssl homepage
• http://gagravarr.org/writing/openssl-certs/index.shtml

Documentation and HOWTOs

• OpenSSL Certificate Authority Setup
• Validating a Certificate Path with OpenSSL
• How SSL and TLS work
• OpenSSL Certificate Authority
• http://dataslinger.com/index.php?/archives/5-Configuring-SSL-certificates-for-Apache,-Dovecot,-Sendmail,-and-IIS.html
• ssl cert HOWTO
• OpenSSL Command-Line HOWTO
• 1. Way: SubjectAltName Only
• OpenSSL Command-Line HOWTO
• How to Create a .PEM file for SSL Certificate Installation
• http://www.tc.umn.edu/~brams006/selfsign.html
• Verifying that a Private Key Matches a Certificate

Dovecot en ssl

Networksolutions certs: After creating myserver.key and myserver.csr and obtaining certs: (don't forget to insert newlines between the blocks!)

cat OV_NetworkSolutionsOVServerCA2.crt OV_USERTrustRSACertificationAuthority.crt AddTrustExternalCARoot.crt > intermediate.pem

In dovecot.conf:

ssl_cert_file = /usr/local/etc/IMAP.EXAMPLE.COM.crt
ssl_key_file = /usr/local/etc/myserver.key
#optional, only if you want to require client to provide cert
#ssl_ca_file = /usr/local/etc/intermediate.pem

Courier-imap and ssl

• http://linsec.ca/Using_Courier-IMAP_and_SSL
• http://linux.seindal.dk/2005/12/04/making-a-courier-imap-ssl-sertificate/

Networksolutions certs: After creating myserver.key and myserver.csr and obtaining certs: (don't forget to insert newlines between the blocks!)

cat AddTrustExternalCARoot.crt NetworkSolutions_CA.crt > intermediate.pem
cat myserver.key >> IMAP.EXAMPLE.COM.crt

In imapd-ssl:

TLS_CERTFILE=/usr/local/etc/courier-certs/IMAP.EXAMPLE.COM.crt
TLS_TRUSTCERTS=/usr/local/etc/courier-certs/intermediate.pem

Network Solutions certificates

See http://blog.irontechsolutions.com/2008/12/10/ssl-chained-certificates-explained/

cat OV_NetworkSolutionsOVServerCA2.crt OV_USERTrustRSACertificationAuthority.crt AddTrustExternalCARoot.crt > intermediate.txt

Generate a signing request

openssl req -nodes -newkey rsa:2048 -keyout my.domain.key -out my.domain.csr

The resulting csr is the signing request, my.domain.key is the private key you save not readable for anyone but root!

Tips&Tricks

Examining certificates

• http://www.madboa.com/geek/openssl/#verify-standard

openssl verify cert.pem

openssl x509 -in cacert.pem -noout -text
openssl x509 -in foo.pem  -inform pem -noout -text 

openssl rsa -noout -text -in server.key
openssl req -noout -text -in server.csr
openssl rsa -noout -text -in ca.key
openssl x509 -noout -text -in ca.crt

Checking a service

1. Note -CApath should point to your local collection of public CA certs

openssl s_client -connect -CApath /etc/ssl/certs host:pop3 -starttls pop3
openssl s_client -port 443 -CApath /etc/ssl/certs -host webmail.tomaatnet.nl -prexit

Check your site

https://www.ssllabs.com/ssltest

Creating your own CA and signing with it

(based on http://www.eclectica.ca/howto/ssl-cert-howto.php#rootc)

cd /etc/ssl
mkdir newcerts
(perform secret rituals)