1 files changed, 35 insertions, 0 deletions

diff --git a/include/net/ah.h b/include/net/ah.h
new file mode 100644
index 000000000000..ceff00afae09
--- /dev/null
+++ b/include/net/ah.h
@@ -0,0 +1,35 @@
+#ifndef _NET_AH_H
+#define _NET_AH_H
+
+#include <net/xfrm.h>
+
+/* This is the maximum truncated ICV length that we know of. */
+#define MAX_AH_AUTH_LEN 12
+
+struct ah_data
+{
+        u8                      *key;
+        int                     key_len;
+        u8                      *work_icv;
+        int                     icv_full_len;
+        int                     icv_trunc_len;
+
+        void                    (*icv)(struct ah_data*,
+                                       struct sk_buff *skb, u8 *icv);
+
+        struct crypto_tfm       *tfm;
+};
+
+static inline void
+ah_hmac_digest(struct ah_data *ahp, struct sk_buff *skb, u8 *auth_data)
+{
+        struct crypto_tfm *tfm = ahp->tfm;
+
+        memset(auth_data, 0, ahp->icv_trunc_len);
+        crypto_hmac_init(tfm, ahp->key, &ahp->key_len);
+        skb_icv_walk(skb, tfm, 0, skb->len, crypto_hmac_update);
+        crypto_hmac_final(tfm, ahp->key, &ahp->key_len, ahp->work_icv);
+        memcpy(auth_data, ahp->work_icv, ahp->icv_trunc_len);
+}
+
+#endif