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#ifndef _NET_AH_H
#define _NET_AH_H
#include <linux/crypto.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
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