Extracting SHA1 Fingerprint of SSL Certificate
davmail is a Microsoft Exachange gateway.
davmail can talk to the Exchange server and export mail folder over IMAP. I
use davmail to read emails from the Exchange server of a client of my
employer. Since this Exchange server is only accessible
over HTTPS, davmail requires the SHA1 fingerprint of the server certificate in
Although Firefox shows the SHA1 fingerprint in its "Certificate Viewer", it won't let me copy the text from there using the clipboard. So, here is how I used OpenSSL command line tools to get what I need.
First get the raw certificate:
echo Q |openssl s_client -connect mail.example.com:443
Copy the lines from
-----BEGIN CERTIFICATE----- to
CERTIFICATE----- to a file, say
cert.pem, and generate the SHA1 fingerprint
openssl x509 -in cert.pem -sha1 -noout -fingerprint
Update: A simpler way to SHA1 fingerprint with the
GnuTLS command line utility,
gnutls-cli -p 443 mail.example.com
SHA-1 fingerprint in the output.