Function ah_output_cb

freebsd/netipsec/xform_ah.c:1070–1150

* AH output callback from the crypto driver. */

 * AH output callback from the crypto driver.
 */
static int
ah_output_cb(struct cryptop *crp)
{
	struct xform_data *xd;
	struct secpolicy *sp;
	struct secasvar *sav;
	struct mbuf *m;
	crypto_session_t cryptoid;
	caddr_t ptr;
	u_int idx;
	int skip, error;

	m = crp->crp_buf.cb_mbuf;
	xd = (struct xform_data *) crp->crp_opaque;
	CURVNET_SET(xd->vnet);
	sp = xd->sp;
	sav = xd->sav;
	skip = xd->skip;
	idx = xd->idx;
	cryptoid = xd->cryptoid;
	ptr = (caddr_t) (xd + 1);

	/* Check for crypto errors. */
	if (crp->crp_etype) {
		if (crp->crp_etype == EAGAIN) {
			/* Reset the session ID */
			if (ipsec_updateid(sav, &crp->crp_session, &cryptoid) != 0)
				crypto_freesession(cryptoid);
			xd->cryptoid = crp->crp_session;
			CURVNET_RESTORE();
			return (crypto_dispatch(crp));
		}
		AHSTAT_INC(ahs_noxform);
		DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
		error = crp->crp_etype;
		m_freem(m);
		goto bad;
	}

	/* Shouldn't happen... */
	if (m == NULL) {
		AHSTAT_INC(ahs_crypto);
		DPRINTF(("%s: bogus returned buffer from crypto\n", __func__));
		error = EINVAL;
		goto bad;
	}
	/*
	 * Copy original headers (with the new protocol number) back
	 * in place.
	 */
	m_copyback(m, 0, skip, ptr);

	free(xd, M_XDATA);
	crypto_freereq(crp);
	AHSTAT_INC(ahs_hist[sav->alg_auth]);
#ifdef REGRESSION
	/* Emulate man-in-the-middle attack when ipsec_integrity is TRUE. */
	if (V_ipsec_integrity) {