Enable passing cast channel certificate authority keys.

extensions/browser/api/cast_channel/cast_auth_util.h

Index: extensions/browser/api/cast_channel/cast_auth_util.h
diff --git a/extensions/browser/api/cast_channel/cast_auth_util.h b/extensions/browser/api/cast_channel/cast_auth_util.h
index 560f698d2b57430d7071dcae8d5b218426a094d9..639aa7ad1cab8f73d10dc654cff976d814a08c51 100644
--- a/extensions/browser/api/cast_channel/cast_auth_util.h
+++ b/extensions/browser/api/cast_channel/cast_auth_util.h
@@ -6,6 +6,9 @@
 #define EXTENSIONS_BROWSER_API_CAST_CHANNEL_CAST_AUTH_UTIL_H_
 
 #include <string>
+#include "crypto/scoped_nss_types.h"
+#include "extensions/common/api/cast_channel/authority_keys.pb.h"
+#include "net/base/hash_value.h"
 
 namespace extensions {
 namespace core_api {
@@ -52,12 +55,52 @@ struct AuthResult {
              int nss_error_code);
 };
 
+// Helper class for intermediate certificate authority validation.
+class AuthorityKeysStore {
+ public:
+  AuthorityKeysStore();
+  ~AuthorityKeysStore();
+
+  // Returns the public key of the ICA whose fingerprint matches |fingerprint|.
+  // Returns NULL, if no such ICA is found.
+  const SECItem* GetICAPublicKeyFromFingerprint(
+      const net::SHA256HashValue& fingerprint);
+
+  // Returns the public key of the first ICA in the list.
+  // Returns NULL if the authority keys store is empty.
+  const SECItem* GetDefaultICAPublicKey();
+
+  // Loads authority keys from a serialized protobuf.
+  bool Load(std::string& keys);
+
+ private:
+  // Info for trusted ICA certs.
+  struct ICACertInfo {
+    const net::SHA256HashValue* fingerprint;
+    SECItem public_key;
+  };
+
+  // The list of trusted certificate authorities, this points to either
+  // hard-coded constant data or to the data in the de-serialized protobuf.
+  std::vector<ICACertInfo> certificate_authorities_;
+
+  // Holds hard-coded constant ICA data.
+  static const ICACertInfo kAllowedICAs[];
+
+  // Trusted certificate authorities data passed from the extension.
+  proto::AuthorityKeys authority_keys_;
+};
+
 // Authenticates the given |challenge_reply|:
 // 1. Signature contained in the reply is valid.
 // 2. Certficate used to sign is rooted to a trusted CA.
 AuthResult AuthenticateChallengeReply(const CastMessage& challenge_reply,
                                       const std::string& peer_cert);
 
+// Sets trusted certificate authorities.
+bool SetTrustedCertificateAuthorities(const std::string& keys,
+                                      const std::string& signature);
+
 }  // namespace cast_channel
 }  // namespace core_api
 }  // namespace extensions