Get certificate fingerprint of HTTPS server from c

Question

Recently Mercurial has added certificate validation when connecting to HTTPS servers. I'm trying to clone the wiki repository for a googlecode project at https://wiki.pydlnadms.googlecode.com/hg/, but the certificate is for *.googlecode.com. I was under the impression that this is called a wildcard domain and valid for all subdomains, but I'm receiving the error:

matt@stanley:~/src$ hg clone https://wiki.pydlnadms.googlecode.com/hg/ pydlnadms-wiki
abort: wiki.pydlnadms.googlecode.com certificate error: certificate is for *.googlecode.com

Allegedly I need to add the certificate fingerprint to my hgrc. How do I retrieve this fingerprint from the command line?

Parent Question: Hosting images on Google Code

Answer 1

This is an old thread but there is an easier way I found. Assuming you have the crt file:

$ cat server.crt|openssl x509 -fingerprint 
MD5 Fingerprint=D1:BA:B0:17:66:6D:7F:42:7B:91:1E:22:7E:3A:27:D2

Answer 2

this is also enough:

openssl x509 -fingerprint -in server.crt

Answer 3

The page at http://wiki.debuntu.org/wiki/OpenSSL#Retrieving_certificate_informations lists the command lines for that (and printing out the relevant information). From that page and some of the man pages, it seems like what you want is (for bash):

openssl s_client -connect <host>:<port> < /dev/null 2>/dev/null | openssl x509 -fingerprint -noout -in /dev/stdin

If you want the whole certificate, leave off the | symbol and everything after it.