Implement Token Binding negotiation TLS extension

net/ssl/ssl_config.h

Index: net/ssl/ssl_config.h
diff --git a/net/ssl/ssl_config.h b/net/ssl/ssl_config.h
index f1c70bb0dc495f04d071bc13ba1968fcd60036f2..755ed9090461e8044757199e1b25ccf2930cc519 100644
--- a/net/ssl/ssl_config.h
+++ b/net/ssl/ssl_config.h
@@ -27,6 +27,12 @@ enum {
   SSL_PROTOCOL_VERSION_TLS1_2 = 0x0303,
 };
 
+enum TokenBindingParam {
+  TB_PARAM_RSA2048_PKCS15_SHA256 = 0,
+  TB_PARAM_RSA2048_PSS_SHA256 = 1,
+  TB_PARAM_ECDSAP256_SHA256 = 2,
+};
+
 // Default minimum protocol version.
 NET_EXPORT extern const uint16_t kDefaultSSLVersionMin;
 
@@ -113,6 +119,11 @@ struct NET_EXPORT SSLConfig {
   bool enable_deprecated_cipher_suites;
 
   bool channel_id_enabled;   // True if TLS channel ID extension is enabled.
+
+  // List of Token Binding key parameters supported by the client. If empty,
+  // Token Binding will be disabled.
+  std::vector<TokenBindingParam> token_binding_params;
+
   bool false_start_enabled;  // True if we'll use TLS False Start.
   // True if the Certificate Transparency signed_certificate_timestamp
   // TLS extension is enabled.