v4.19.13 snapshot.
diff --git a/include/net/ah.h b/include/net/ah.h
new file mode 100644
index 0000000..2d2dea5
--- /dev/null
+++ b/include/net/ah.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _NET_AH_H
+#define _NET_AH_H
+
+#include <linux/skbuff.h>
+
+struct crypto_ahash;
+
+struct ah_data {
+ int icv_full_len;
+ int icv_trunc_len;
+
+ struct crypto_ahash *ahash;
+};
+
+struct ip_auth_hdr;
+
+static inline struct ip_auth_hdr *ip_auth_hdr(const struct sk_buff *skb)
+{
+ return (struct ip_auth_hdr *)skb_transport_header(skb);
+}
+
+#endif