Certificate Transparency: New Part of PKI Infrastructure

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Certificate transparency: New part of PKI infrastructure A presentation by Dmitry Belyavsky, TCI ENOG 7 Moscow, May 26-27, 2014 About PKI *) *) PKI (public-key infrastructure) is a set of hardware, software, people, policies, and procedures needed to create, manage, distribute, use, store, and revoke digital certificates Check the server certificate The server certificate signed correctly by any of them? Many trusted CAs NO YES Everything seems to We warn the user be ok! DigiNotar case OCSP requests for the fake *.google.com certificate Source: FOX-IT, Interim Report, http://cryptome.org/0005/diginotar-insec.pdf PKI: extra trust Independent Trusted PKI source certificate DANE (RFC 6698) Certificate pinning Limited browsers support Mozilla Certificate Patrol, Chrome cache for Google certificates Certificate transparency (RFC 6962) Inspired by Google (Support in Chrome appeared) One of the authors - Ben Laurie (OpenSSL Founder) CA support – Comodo Certificate Transparency: how it works • Log accepts cert => SCT Client • Is SCT present and signed correctly? Client • Is SCT present and signed correctly? Auditor • Does log server behave correctly? Monitor • Any suspicious certs? Certificate Transparency: how it works Source: http://www.certificate-transparency.org Certificate Transparency how it works Source: http://www.certificate-transparency.org Certificate Transparency current state Google Chrome Support (33+) http://www.certificate-transparency.org/certificate-transparency-in-chrome Google Cert EV plan http://www.certificate-transparency.org/ev-ct-plan Certificate Transparency current state Open source code 2 pilot logs Certificate Transparency: protect from what? SAVE from MITM attack ü Warning from browser ü Site owner can watch logs for certs Do NOT SAVE from HEARTBLEED! Certificate transparency and Russian GOST crypto Russian GOST does not save from the MITM attack Algorithm SHA-256 >>> GOSTR34.11-2012 Key >>> GOST R 34.10-2012 Q&A Questions? Drop ‘em at: [email protected] .

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