Openssl

Links

• Why you don't want EV certificate
• SSL confg generator
• openssl homepage
• http://gagravarr.org/writing/openssl-certs/index.shtml

Tools

• openssl
• sslscan
• sclient
• gnutls-cli

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
• Getting your certificate chain right
• Verify certificate chain
• What is my certificate chain?
• Checking A Remote Certificate Chain With OpenSSL

• Check SSL Certificate Chain with OpenSSL Examples

Dovecot and 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 bundle

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

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

Comodo bundle order

COMODORSAOrganizationValidationSecureServerCA. + COMODO rsa add trust ca ( + addtrustexternalcaroot )

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!

HOWTO

Generate PSK

openssl rand -hex 32

Converting certificates

https://stackoverflow.com/questions/13732826/convert-pem-to-crt-and-key

Create private key (using config file)

openssl req (-config /etc/pki/tls/www.example.com.cnf) -newkey rsa:2048 -nodes -keyout domain.key

Create CSR using config file

openssl req -config /etc/pki/tls/www.example.com.cnf -new -newkey rsa:2048 -nodes -keyout example.com.key -out www.example.com.csr

Convert der to pem

openssl x509 -inform der -in certificate.cer -out certificate.pem

Creating CSR for multiple hosts

For example http://blog.endpoint.com/2014/10/openssl-csr-with-alternative-names-one.html

Remove password from private key

https://wiki.apache.org/httpd/RemoveSSLCertPassPhrase

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

with expiration date:

openssl x509 -noout -text -enddate -in ca.crt

1. to check CN

openssl x509 -in server.crt -noout -subject

openssl pkcs12 -info -in keyStore.p12
openssl pkcs12 -info -in keyStore.pfx

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.example.com -prexit
openssl s_client -connect imap.example.com:143 -starttls imap
openssl s_client -connect web.server:443 -showcerts
openssl s_client -connect webmail.example.com:443 -servername vhost.example.com

Just check expiration date:

 openssl s_client -connect imap.example.com:143 -starttls imap 2>/dev/null | openssl x509 -noout -dates

 

Check your site

• https://www.ssllabs.com/ssltest
• https://www.sslcheck.nl/
• Internet.nl

gnutls-cli

echo quit | gnutls-cli --starttls-proto smtp --port 25 servac.skk | grep Status
echo quit | gnutls-cli --port 465 servac.skk | grep Status

check if certs match

TODO: -clr_check too

openssl pkey -in privateKey.key -pubout -outform pem | sha256sum 
openssl x509 -in certificate.crt -pubkey -noout -outform pem | sha256sum 
openssl req -in CSR.csr -pubkey -noout -outform pem | sha256sum

These values show match Also:

openssl verify -CAfile ca-bundle foo_bar.crt

A script to do these checks: [sslcheck]

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)

Check which ciphers and tls versions your openssl supports

openssl ciphers -v

FAQ

Error messages

OpenSSL: error:0A000102:SSL routines::unsupported protocol

This could becaure you're trying to an older version of TLS, check openssl.cnf for

CipherString = DEFAULT:@SECLEVEL=2

which means it enforces minimum of TLSv1.2

You might now get

OpenSSL: error:0A000152:SSL routines::unsafe legacy renegotiation disabled

which means add below the CipherString line:

Options = UnsafeLegacyRenegotiation

Get issuer

openssl s_client -showcerts -connect <YOURHOST>:443 < /dev/null 2>/dev/null |grep -i issuer

Order of certificates in bundle

Root CA comes last

using s_client

no client certificate sent

try adding -cert

 

Secure Renegotiation IS NOT supported

Probably using wrong TLS version

Can't use SSL_get_servername

Try using hostname instead of IP address

write:errno=104

server reset the connection

no peer certificate available

Could be trying to talk tls to ssl?

Verification error: unable to verify the first certificate

problem missing CA cert

error 20 at 0 depth lookup: unable to get local issuer certificate

you probably need to provide the right -CAfile maybe self signed?

 

Verify return code: 21 (unable to verify the first certificate)

Probably requires bundle

 

Bad certificate (code 42)

Means the server demands you authenticate with a certificate, and you did not do so, and that caused the handshake failure.

 

check certificate chain

openssl s_client -connect www.example.com:443 -showcerts
      

 

Some of the output

Certificate chain

0 s:CN = foo.local
  i:CN = foo.local-CA

0: first in chain

s: subject  ( openssl x509 -noout -in foo.crt -subject )

i: issuer ( openssl x509 -noout -in foo.crt -issuer )

OR

openssl s_client -showcerts -verify 5 -connect ldap.example.com:636  < /dev/null | awk '/BEGIN/,/END/{ if(/BEGIN/)    {a++}; out="bluePage-cert"a".pem"; print >out}' 

or

openssl s_client -showcerts -verify 5 -connect ldap.example.com:389 starttls ldap  < /dev/null | awk '/BEGIN/,/END/{ if(/BEGIN/)    {a++}; out="bluePage-cert"a".pem"; print >out}'

check expiration date

echo | openssl s_client -servername NAME -connect HOST:PORT 2>/dev/null | openssl x509 -noout -dates

openssl x509 -enddate -noout -in file.pem

139814102202256:error:0906D06C:PEM routines:PEM_read_bio:no start line:pem_lib.c:707:Expecting: TRUSTED CERTIFICATE

i've seen this happen when someone deleted the BEGIN/END CERTIFICATE lines

or a file is in DER format

SSL CTX certificate file error: error:0906D06C:PEM routines:PEM_read_bio:no start line

??

 

 

check if webserver supports old tls

openssl s_client -connect www.example.com:443 -tls1
openssl s_client -connect www.example.com:443 -tls1_1

or when vhost:

 openssl s_client -servername vhost.example.com -connect www.example.com:443 -tls1_1

 

ERROR: Certificate verification: Not trusted

seems to be an lftp issue

unsupported certificate purpose

??

 

ssllabs checks

Chain issues: Incorrect order, Contains anchor

Could be the topmost cert in the bundle provided, try removing it

 

Chain issues: Contains anchor

Seems to mean there's a root ca in the bundle

check smtp submission

echo -n "username" | base64
echo -n "password" | base64

openssl s_client -connect mail.host.com:587 -starttls smtp -crlf

EHLO foo.bar
AUTH LOGIN

base64username

base64password

OR

echo -ne '\0username\0password'| base64
AUTH LOGIN output_of_that_echo

p12 / pkcs12

https://fileinfo.com/extension/p12

openssl pkcs12 -in yourP12File.pfx -nocerts -out privateKey.pem
openssl pkcs12 -in yourP12File.pfx -clcerts -nokeys -out publicCert.pem

server certificate does NOT include an ID which matches the server name

todo