v4.19.13 snapshot.
diff --git a/include/uapi/linux/if_alg.h b/include/uapi/linux/if_alg.h
new file mode 100644
index 0000000..bc2bcde
--- /dev/null
+++ b/include/uapi/linux/if_alg.h
@@ -0,0 +1,43 @@
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+/*
+ * if_alg: User-space algorithm interface
+ *
+ * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ */
+
+#ifndef _LINUX_IF_ALG_H
+#define _LINUX_IF_ALG_H
+
+#include <linux/types.h>
+
+struct sockaddr_alg {
+ __u16 salg_family;
+ __u8 salg_type[14];
+ __u32 salg_feat;
+ __u32 salg_mask;
+ __u8 salg_name[64];
+};
+
+struct af_alg_iv {
+ __u32 ivlen;
+ __u8 iv[0];
+};
+
+/* Socket options */
+#define ALG_SET_KEY 1
+#define ALG_SET_IV 2
+#define ALG_SET_OP 3
+#define ALG_SET_AEAD_ASSOCLEN 4
+#define ALG_SET_AEAD_AUTHSIZE 5
+
+/* Operations */
+#define ALG_OP_DECRYPT 0
+#define ALG_OP_ENCRYPT 1
+
+#endif /* _LINUX_IF_ALG_H */