diff --git a/src/net/tools/naive/socks5_server_socket.cc b/src/net/tools/naive/socks5_server_socket.cc
index 936d32b46f..d7d691b0ca 100644
--- a/src/net/tools/naive/socks5_server_socket.cc
+++ b/src/net/tools/naive/socks5_server_socket.cc
@@ -20,14 +20,20 @@
 
 namespace net {
 
-const unsigned int Socks5ServerSocket::kGreetReadHeaderSize = 2;
-const unsigned int Socks5ServerSocket::kReadHeaderSize = 5;
-const char Socks5ServerSocket::kSOCKS5Version = '\x05';
-const char Socks5ServerSocket::kSOCKS5Reserved = '\x00';
-const char Socks5ServerSocket::kAuthMethodNone = '\x00';
-const char Socks5ServerSocket::kAuthMethodNoAcceptable = '\xff';
-const char Socks5ServerSocket::kReplySuccess = '\x00';
-const char Socks5ServerSocket::kReplyCommandNotSupported = '\x07';
+enum SocksCommandType {
+  kCommandConnect = 0x01,
+  kCommandBind = 0x02,
+  kCommandUDPAssociate = 0x03,
+};
+
+static constexpr unsigned int kGreetReadHeaderSize = 2;
+static constexpr unsigned int kReadHeaderSize = 5;
+static constexpr char kSOCKS5Version = '\x05';
+static constexpr char kSOCKS5Reserved = '\x00';
+static constexpr char kAuthMethodNone = '\x00';
+static constexpr char kAuthMethodNoAcceptable = '\xff';
+static constexpr char kReplySuccess = '\x00';
+static constexpr char kReplyCommandNotSupported = '\x07';
 
 static_assert(sizeof(struct in_addr) == 4, "incorrect system size of IPv4");
 static_assert(sizeof(struct in6_addr) == 16, "incorrect system size of IPv6");
diff --git a/src/net/tools/naive/socks5_server_socket.h b/src/net/tools/naive/socks5_server_socket.h
index 1f1a888c5d..988c233cf9 100644
--- a/src/net/tools/naive/socks5_server_socket.h
+++ b/src/net/tools/naive/socks5_server_socket.h
@@ -92,21 +92,6 @@ class Socks5ServerSocket : public StreamSocket {
     kEndPointResolvedIPv6 = 0x04,
   };
 
-  enum SocksCommandType {
-    kCommandConnect = 0x01,
-    kCommandBind = 0x02,
-    kCommandUDPAssociate = 0x03,
-  };
-
-  static const unsigned int kGreetReadHeaderSize;
-  static const unsigned int kReadHeaderSize;
-  static const char kSOCKS5Version;
-  static const char kSOCKS5Reserved;
-  static const char kAuthMethodNone;
-  static const char kAuthMethodNoAcceptable;
-  static const char kReplySuccess;
-  static const char kReplyCommandNotSupported;
-
   void DoCallback(int result);
   void OnIOComplete(int result);
   void OnReadWriteComplete(CompletionOnceCallback callback, int result);