[PROTON-1088] Add convenience functions to obtain the client certificate fingerprint, subject subfields

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: proton-0.11.1
• Fix Version/s: proton-0.12.0
• Component/s: proton-c
• Assignee: Ganesh Murthy
• Reporter: Ganesh Murthy
• Created: 05/Jan/16 18:23
• Updated: 02/Oct/19 17:55
• Resolved: 25/Jan/16 13:53

Description

1. Provide a convenience function which will return a an ssl certificate fingerprint (a sha1 or sha256 hash of the certificate).
– When you look go to a https site via a web browser, you can look at the certificate fingerprint by clicking the View Certificate button on the browser. Add a convenience function to proton which will return the char array of octets. sha1 hashing produces a 20 octet hash and sha256 provides a 32 octet hash. The function signature should approximately look like this -
void pn_ssl_get_fingerprint(pn_ssl_t *ssl0, unsigned char *md, const char* digest_name)

2. The subject field on the SSL cert has many subfields like -
C = ISO3166 two character country code
ST = state or province
L = Locality; generally means city
O = Organization - Company Name
OU = Organization Unit - division or unit
CN = CommonName - end entity name e.g. www.example.com
Provide convenience functions to obtain values of the above subfields.