https: add support for DNS exclusion and switch to TXT records.

(This code has no effect unless --enable-dnssec-certs is given.)

The existing DNSSEC code will process embeded chains in certificates
and validate CERT records there in. The format of the CERT record was
just something made up as a proof of concept. This change switches
that code to using TXT records which are at least used by some other
code.

Additionally, when --enable-dnssec-certs is given. TXT record lookups
are triggered for each HTTPS connection. If DNSSEC secure, these
lookups can validate a HTTPS certificate. Even without DNSSEC, they
can by used for exclusion: if TLS fingerprints are given, but the
certificate doesn't match any of them, then the certificate is
rejected.

The next step in this series will be to perform the TXT lookup for
some percentage of dev channel users in order to measure the latency
impact. For this experiment, all behavioural changes will be disabled.

BUG=none
TEST=net_unittests

http://codereview.chromium.org/3148037/show

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@57787 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 8 insertions, 0 deletions

diff --git a/net/base/dnssec_chain_verifier.h b/net/base/dnssec_chain_verifier.h
index 2556564..096dea1 100644
--- a/net/base/dnssec_chain_verifier.h
+++ b/net/base/dnssec_chain_verifier.h
@@ -5,6 +5,7 @@
 #ifndef NET_BASE_DNSSEC_CHAIN_VERIFIER_H_
 #define NET_BASE_DNSSEC_CHAIN_VERIFIER_H_
 
+#include <map>
 #include <string>
 #include <vector>
 
@@ -54,6 +55,13 @@ class DNSSECChainVerifier {
   // this after Verify has returned OK.
   const std::vector<base::StringPiece>& rrdatas() const;
 
+  // ParseTLSTXTRecord parses a TXT record which should contain TLS fingerprint
+  // information.
+  //   rrdata: the raw TXT RRDATA from DNS
+  //   returns: an empty map on failure, or the result of the parse.
+  static std::map<std::string, std::string>
+  ParseTLSTXTRecord(base::StringPiece rrdata);
+
   // Exposed for testing only.
   static unsigned MatchingLabels(base::StringPiece a,
                                  base::StringPiece b);