Update Token Binding code to match latest draft draft-ietf-tokbind-protocol-04

net/socket/ssl_client_socket_openssl.cc

Index: net/socket/ssl_client_socket_openssl.cc
diff --git a/net/socket/ssl_client_socket_openssl.cc b/net/socket/ssl_client_socket_openssl.cc
index 501eaefce0a6b16b34b869826966c31882dcc950..355fd508ace5afaa4a4a108e48c643476c240555 100644
--- a/net/socket/ssl_client_socket_openssl.cc
+++ b/net/socket/ssl_client_socket_openssl.cc
@@ -87,9 +87,9 @@ const unsigned int kTbExtNum = 30033;
 
 // Token Binding ProtocolVersions supported.
 const uint8_t kTbProtocolVersionMajor = 0;
-const uint8_t kTbProtocolVersionMinor = 3;
+const uint8_t kTbProtocolVersionMinor = 4;
 const uint8_t kTbMinProtocolVersionMajor = 0;
-const uint8_t kTbMinProtocolVersionMinor = 2;
+const uint8_t kTbMinProtocolVersionMinor = 3;

[davidben, 2016/01/28 18:27:55]

Where did these numbers come from? I don't see them in the spec. (It's possible
I'm just failing to find it.)

[nharper, 2016/01/28 19:06:07]

This comes from draft-ietf-tokbind-negotiation-02, section 2: "Prototype
implementations of Token Binding drafts can indicate support of a specific draft
version, e.g. {0, 1} or {0, 2}."

Since draft-ietf-tokbind-protocol-04 is the latest spec, I'm assuming that {0,4}
is the ProtocolVersion to indicate. The min version {0,3} comes from me looking
through the previous drafts to see what is compatible with the latest version.
The only change (relevant to the implementation) in draft 04 was to move the
TokenBindingType from one struct to another, but it ends up serialized the same
on the wire, so it's compatible with the previous version. It's not compatible
with {0,2}.

You may notice that this code previously indicated it supported versions {0,2}
and {0,3}. I believe that was a bug in the code.

 
 void FreeX509Stack(STACK_OF(X509)* ptr) {
   sk_X509_pop_free(ptr, X509_free);