Openssl

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Revision as of 04:33, 25 February 2013 by Saurabh (talk | contribs)

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openssl

Creating self-signed pem certificates for HTTPS

We can create self-signed pem ceritifcates using openssl for HTTPS, SMTPS, etc. using:

openssl req -x509 -nodes -days 9999 -newkey rsa:1024 -keyout mycert.pem -out mycert.pem

The life of certificate is set to 9999 so that it never expires.


Creating certificate request with OpenSSL

To create certificate request with OpenSSL we can use:

openssl genrsa -des3 -out client1.key 2048
openssl req -new -key client1.key -days 365 -out client1.csr

Remember the password supplied while generating key, as that password would be asked whenever we try to generate a new request with the key. Challenge password asked at the end when we create a new certificate request can be left blank.


Checking whether a given certificate and key pair match

To check whether a given key and certificate pair match one can use:

openssl rsa -noout -modulus -in <key-file> | openssl md5
openssl x509 -noout -modulus -in <certificate-file> | openssl md5

If both the commands result into exactly same output then the certificate and key pair match, otherwise there is a problem. Note that as per http://stackoverflow.com/questions/4658484/ssl-install-problem-key-value-mismatch-but-they-do-match just matching of modulus is not enough. Not sure if it is really so or not.


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