diff --git a/libc/kernel/uapi/linux/handshake.h b/libc/kernel/uapi/linux/handshake.h
new file mode 100644
index 0000000..e9923ae
--- /dev/null
+++ b/libc/kernel/uapi/linux/handshake.h
@@ -0,0 +1,73 @@
+/****************************************************************************
+ ****************************************************************************
+ ***
+ ***   This header was automatically generated from a Linux kernel header
+ ***   of the same name, to make information necessary for userspace to
+ ***   call into the kernel available to libc.  It contains only constants,
+ ***   structures, and macros generated from the original header, and thus,
+ ***   contains no copyrightable information.
+ ***
+ ***   To edit the content of this header, modify the corresponding
+ ***   source file (e.g. under external/kernel-headers/original/) then
+ ***   run bionic/libc/kernel/tools/update_all.py
+ ***
+ ***   Any manual change here will be lost the next time this script will
+ ***   be run. You've been warned!
+ ***
+ ****************************************************************************
+ ****************************************************************************/
+#ifndef _UAPI_LINUX_HANDSHAKE_H
+#define _UAPI_LINUX_HANDSHAKE_H
+#define HANDSHAKE_FAMILY_NAME "handshake"
+#define HANDSHAKE_FAMILY_VERSION 1
+enum handshake_handler_class {
+  HANDSHAKE_HANDLER_CLASS_NONE,
+  HANDSHAKE_HANDLER_CLASS_TLSHD,
+  HANDSHAKE_HANDLER_CLASS_MAX,
+};
+enum handshake_msg_type {
+  HANDSHAKE_MSG_TYPE_UNSPEC,
+  HANDSHAKE_MSG_TYPE_CLIENTHELLO,
+  HANDSHAKE_MSG_TYPE_SERVERHELLO,
+};
+enum handshake_auth {
+  HANDSHAKE_AUTH_UNSPEC,
+  HANDSHAKE_AUTH_UNAUTH,
+  HANDSHAKE_AUTH_PSK,
+  HANDSHAKE_AUTH_X509,
+};
+enum {
+  HANDSHAKE_A_X509_CERT = 1,
+  HANDSHAKE_A_X509_PRIVKEY,
+  __HANDSHAKE_A_X509_MAX,
+  HANDSHAKE_A_X509_MAX = (__HANDSHAKE_A_X509_MAX - 1)
+};
+enum {
+  HANDSHAKE_A_ACCEPT_SOCKFD = 1,
+  HANDSHAKE_A_ACCEPT_HANDLER_CLASS,
+  HANDSHAKE_A_ACCEPT_MESSAGE_TYPE,
+  HANDSHAKE_A_ACCEPT_TIMEOUT,
+  HANDSHAKE_A_ACCEPT_AUTH_MODE,
+  HANDSHAKE_A_ACCEPT_PEER_IDENTITY,
+  HANDSHAKE_A_ACCEPT_CERTIFICATE,
+  HANDSHAKE_A_ACCEPT_PEERNAME,
+  __HANDSHAKE_A_ACCEPT_MAX,
+  HANDSHAKE_A_ACCEPT_MAX = (__HANDSHAKE_A_ACCEPT_MAX - 1)
+};
+enum {
+  HANDSHAKE_A_DONE_STATUS = 1,
+  HANDSHAKE_A_DONE_SOCKFD,
+  HANDSHAKE_A_DONE_REMOTE_AUTH,
+  __HANDSHAKE_A_DONE_MAX,
+  HANDSHAKE_A_DONE_MAX = (__HANDSHAKE_A_DONE_MAX - 1)
+};
+enum {
+  HANDSHAKE_CMD_READY = 1,
+  HANDSHAKE_CMD_ACCEPT,
+  HANDSHAKE_CMD_DONE,
+  __HANDSHAKE_CMD_MAX,
+  HANDSHAKE_CMD_MAX = (__HANDSHAKE_CMD_MAX - 1)
+};
+#define HANDSHAKE_MCGRP_NONE "none"
+#define HANDSHAKE_MCGRP_TLSHD "tlshd"
+#endif