revert tun(4) changes for now, breaks in kdump build (TUNSCAP/TIOCEXT clash)

tb@ agrees

2 files changed, 6 insertions, 212 deletions

diff --git a/sys/net/if_tun.c b/sys/net/if_tun.c
index 2d304d93e3c..432d2b6154e 100644
--- a/sys/net/if_tun.c
+++ b/sys/net/if_tun.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_tun.c,v 1.245 2024/11/14 01:51:57 dlg Exp $	*/
+/*	$OpenBSD: if_tun.c,v 1.246 2024/11/14 13:47:38 sthen Exp $	*/
 /*	$NetBSD: if_tun.c,v 1.24 1996/05/07 02:40:48 thorpej Exp $	*/
 
 /*
@@ -88,7 +88,6 @@ struct tun_softc {
 	struct sigio_ref	sc_sigio;	/* async I/O registration */
 	unsigned int		sc_flags;	/* misc flags */
 #define TUN_DEAD			(1 << 16)
-#define TUN_HDR				(1 << 17)
 
 	dev_t			sc_dev;
 	struct refcnt		sc_refs;
@@ -105,13 +104,6 @@ int	tundebug = TUN_DEBUG;
 /* Pretend that these IFF flags are changeable by TUNSIFINFO */
 #define TUN_IFF_FLAGS (IFF_POINTOPOINT|IFF_MULTICAST|IFF_BROADCAST)
 
-#define TUN_IF_CAPS ( \
-	IFCAP_CSUM_IPv4 | \
-	IFCAP_CSUM_TCPv4|IFCAP_CSUM_UDPv4|IFCAP_CSUM_TCPv6|IFCAP_CSUM_UDPv6 | \
-	IFCAP_VLAN_MTU|IFCAP_VLAN_HWTAGGING|IFCAP_VLAN_HWOFFLOAD | \
-	IFCAP_TSOv4|IFCAP_TSOv6|IFCAP_LRO \
-)
-
 void	tunattach(int);
 
 int	tun_dev_open(dev_t, const struct if_clone *, int, struct proc *);
@@ -504,11 +496,10 @@ tun_dev_close(dev_t dev, struct proc *p)
 	 */
 	NET_LOCK();
 	CLR(ifp->if_flags, IFF_UP | IFF_RUNNING);
-	CLR(ifp->if_capabilities, TUN_IF_CAPS);
 	NET_UNLOCK();
 	ifq_purge(&ifp->if_snd);
 
-	CLR(sc->sc_flags, TUN_ASYNC|TUN_HDR);
+	CLR(sc->sc_flags, TUN_ASYNC);
 	sigio_free(&sc->sc_sigio);
 
 	if (!ISSET(sc->sc_flags, TUN_DEAD)) {
@@ -636,51 +627,6 @@ tapioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
 	return (tun_dev_ioctl(dev, cmd, data));
 }
 
-static int
-tun_set_capabilities(struct tun_softc *sc, const struct tun_capabilities *cap)
-{
-	if (ISSET(cap->tun_if_capabilities, ~TUN_IF_CAPS))
-		return (EINVAL);
-
-	KERNEL_ASSERT_LOCKED();
-	SET(sc->sc_flags, TUN_HDR);
-
-	NET_LOCK();
-	CLR(sc->sc_if.if_capabilities, TUN_IF_CAPS);
-	SET(sc->sc_if.if_capabilities, cap->tun_if_capabilities);
-	NET_UNLOCK();
-	return (0);
-}
-
-static int
-tun_get_capabilities(struct tun_softc *sc, struct tun_capabilities *cap)
-{
-	int error = 0;
-
-	NET_LOCK_SHARED();
-	if (ISSET(sc->sc_flags, TUN_HDR)) {
-		cap->tun_if_capabilities =
-		    (sc->sc_if.if_capabilities & TUN_IF_CAPS);
-	} else
-		error = ENODEV;
-	NET_UNLOCK_SHARED();
-
-	return (error);
-}
-
-static int
-tun_del_capabilities(struct tun_softc *sc)
-{
-	NET_LOCK();
-	CLR(sc->sc_if.if_capabilities, TUN_IF_CAPS);
-	NET_UNLOCK();
-
-	KERNEL_ASSERT_LOCKED();
-	CLR(sc->sc_flags, TUN_HDR);
-
-	return (0);
-}
-
 int
 tun_dev_ioctl(dev_t dev, u_long cmd, void *data)
 {
@@ -732,18 +678,6 @@ tun_dev_ioctl(dev_t dev, u_long cmd, void *data)
 		}
 		break;
 
-	case TUNSCAP:
-		error = tun_set_capabilities(sc,
-		    (const struct tun_capabilities *)data);
-		break;
-	case TUNGCAP:
-		error = tun_get_capabilities(sc,
-		    (struct tun_capabilities *)data);
-		break;
-	case TUNDCAP:
-		error = tun_del_capabilities(sc);
-		break;
-
 	case FIONBIO:
 		break;
 	case FIOASYNC:
@@ -811,7 +745,6 @@ tun_dev_read(dev_t dev, struct uio *uio, int ioflag)
 	struct tun_softc	*sc;
 	struct ifnet		*ifp;
 	struct mbuf		*m, *m0;
-	size_t			 len;
 	int			 error = 0;
 
 	sc = tun_get(dev);
@@ -830,46 +763,9 @@ tun_dev_read(dev_t dev, struct uio *uio, int ioflag)
 		bpf_mtap(ifp->if_bpf, m0, BPF_DIRECTION_OUT);
 #endif
 
-	if (ISSET(sc->sc_flags, TUN_HDR)) {
-		struct tun_hdr th;
-
-		KASSERT(ISSET(m0->m_flags, M_PKTHDR));
-
-		th.th_flags = 0;
-		if (ISSET(m0->m_pkthdr.csum_flags, M_IPV4_CSUM_OUT))
-			SET(th.th_flags, TUN_H_IPV4_CSUM);
-		if (ISSET(m0->m_pkthdr.csum_flags, M_TCP_CSUM_OUT))
-			SET(th.th_flags, TUN_H_TCP_CSUM);
-		if (ISSET(m0->m_pkthdr.csum_flags, M_UDP_CSUM_OUT))
-			SET(th.th_flags, TUN_H_UDP_CSUM);
-		if (ISSET(m0->m_pkthdr.csum_flags, M_ICMP_CSUM_OUT))
-			SET(th.th_flags, TUN_H_ICMP_CSUM);
-
-		th.th_pad = 0;
-
-		th.th_vtag = 0;
-		if (ISSET(m0->m_flags, M_VLANTAG)) {
-			SET(th.th_flags, TUN_H_VTAG);
-			th.th_vtag = m0->m_pkthdr.ether_vtag;
-		}
-
-		th.th_mss = 0;
-		if (ISSET(m0->m_pkthdr.csum_flags, M_TCP_TSO)) {
-			SET(th.th_flags, TUN_H_TCP_MSS);
-			th.th_mss = m0->m_pkthdr.ph_mss;
-		}
-
-		len = ulmin(uio->uio_resid, sizeof(th));
-		if (len > 0) {
-			error = uiomove(&th, len, uio);
-			if (error != 0)
-				goto free;
-		}
-	}
-
 	m = m0;
 	while (uio->uio_resid > 0) {
-		len = ulmin(uio->uio_resid, m->m_len);
+		size_t len = ulmin(uio->uio_resid, m->m_len);
 		if (len > 0) {
 			error = uiomove(mtod(m, void *), len, uio);
 			if (error != 0)
@@ -881,7 +777,6 @@ tun_dev_read(dev_t dev, struct uio *uio, int ioflag)
 			break;
 	}
 
-free:
 	m_freem(m0);
 
 put:
@@ -912,8 +807,6 @@ tun_dev_write(dev_t dev, struct uio *uio, int ioflag, int align)
 	struct mbuf		*m0;
 	int			error = 0;
 	size_t			mlen;
-	size_t			hlen;
-	struct tun_hdr		th;
 
 	sc = tun_get(dev);
 	if (sc == NULL)
@@ -921,11 +814,8 @@ tun_dev_write(dev_t dev, struct uio *uio, int ioflag, int align)
 
 	ifp = &sc->sc_if;
 
-	hlen = ifp->if_hdrlen;
-	if (ISSET(sc->sc_flags, TUN_HDR))
-		hlen += sizeof(th);
-	if (uio->uio_resid < hlen ||
-	    uio->uio_resid > (hlen + ifp->if_hardmtu)) {
+	if (uio->uio_resid < ifp->if_hdrlen ||
+	    uio->uio_resid > (ifp->if_hdrlen + ifp->if_hardmtu)) {
 		error = EMSGSIZE;
 		goto put;
 	}
@@ -950,52 +840,6 @@ tun_dev_write(dev_t dev, struct uio *uio, int ioflag, int align)
 	m0->m_pkthdr.len = m0->m_len = mlen;
 	m_adj(m0, align);
 
-	if (ISSET(sc->sc_flags, TUN_HDR)) {
-		error = uiomove(&th, sizeof(th), uio);
-		if (error != 0)
-			goto drop;
-
-		if (ISSET(th.th_flags, TUN_H_IPV4_CSUM)) {
-			SET(m0->m_pkthdr.csum_flags,
-			    M_IPV4_CSUM_OUT | M_IPV4_CSUM_IN_OK);
-		}
-
-		switch (th.th_flags &
-		    (TUN_H_TCP_CSUM|TUN_H_UDP_CSUM|TUN_H_ICMP_CSUM)) {
-		case 0:
-			break;
-		case TUN_H_TCP_CSUM:
-			SET(m0->m_pkthdr.csum_flags,
-			    M_TCP_CSUM_OUT | M_TCP_CSUM_IN_OK);
-			break;
-		case TUN_H_UDP_CSUM:
-			SET(m0->m_pkthdr.csum_flags,
-			    M_UDP_CSUM_OUT | M_UDP_CSUM_IN_OK);
-			break;
-		case TUN_H_ICMP_CSUM:
-			SET(m0->m_pkthdr.csum_flags,
-			    M_ICMP_CSUM_OUT | M_ICMP_CSUM_IN_OK);
-			break;
-		default:
-			error = EINVAL;
-			goto drop;
-		}
-
-		if (ISSET(th.th_flags, TUN_H_VTAG)) {
-			if (!ISSET(sc->sc_flags, TUN_LAYER2)) {
-				error = EINVAL;
-				goto drop;
-			}
-			SET(m0->m_flags, M_VLANTAG);
-			m0->m_pkthdr.ether_vtag = th.th_vtag;
-		}
-
-		if (ISSET(th.th_flags, TUN_H_TCP_MSS)) {
-			SET(m0->m_pkthdr.csum_flags, M_TCP_TSO);
-			m0->m_pkthdr.ph_mss = th.th_mss;
-		}
-	}
-
 	error = uiomove(mtod(m0, void *), m0->m_len, uio);
 	if (error != 0)
 		goto drop;
diff --git a/sys/net/if_tun.h b/sys/net/if_tun.h
index 77aa868e794..3e17f0d10b1 100644
--- a/sys/net/if_tun.h
+++ b/sys/net/if_tun.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_tun.h,v 1.16 2024/11/14 01:51:57 dlg Exp $	*/
+/*	$OpenBSD: if_tun.h,v 1.17 2024/11/14 13:47:38 sthen Exp $	*/
 
 /*
  * Copyright (c) 1988, Julian Onions <Julian.Onions@nexor.co.uk>
@@ -31,48 +31,6 @@
 
 #include <sys/ioccom.h>
 
-/*
- * tun_hdr is a multiple of 4 bytes, but is built out of uint16_t
- * fields. This allows it to sit on a 2 byte boundary in front of
- * either IP (and MPLS) or Ethernet packets for tun(4) and tap(4)
- * interfaces respectively while maintaining the alignment of their
- * payloads.
- *
- * Userland can request the use of the tun_hdr using the TUNSCAP
- * ioctl. This ioctl also allows userland to specify which "offload"
- * capabilities it is able to accept in packets it will read from the
- * kernel. It is acceptable to enable tun_hdr without enabling any
- * interface offload capabilities.
- *
- * Once the tap_hdr is enabled, userland can write packets into the
- * kernel with any of the supported features. tun(4)/tap(4) reads
- * will unconditionally handle any features specified on the packet,
- * regardless of what capabilities were specified by the TUNSCAP
- * ioctl.
- *
- * The tun_hdr can be read from one interface and written directly
- * to another without interpretation or modification.
- *
- * Use of tun_hdr and the associated capabilities are reset when a
- * tun(4)/tap(4) device is closed.
- */
-
-struct tun_hdr {
-	uint16_t	th_flags;
-#define TUN_H_VTAG		(1 << 0)  /* th_vtag is set */
-#define TUN_H_TCP_MSS		(1 << 1)  /* Cut TCP frame up by th_mss */
-
-#define TUN_H_IPV4_CSUM		(1 << 8)
-#define TUN_H_TCP_CSUM		(1 << 9)
-#define TUN_H_UDP_CSUM		(1 << 10)
-#define TUN_H_ICMP_CSUM		(1 << 11)
-
-	uint16_t	th_pad;
-
-	uint16_t	th_vtag;
-	uint16_t	th_mss;
-};
-
 #define	TUN_OPEN	0x0001
 #define	TUN_INITED	0x0002
 #define	TUN_RCOLL	0x0004	/* unused */
@@ -110,12 +68,4 @@ struct tuninfo {
 #define	TUNSDEBUG	_IOW('t', 94, int)
 #define	TUNGDEBUG	_IOR('t', 95, int)
 
-struct tun_capabilities {
-	uint32_t	tun_if_capabilities; /* IFCAP_* from net/if.h */
-};
-
-#define	TUNSCAP		_IOW('t', 96, struct tun_capabilities)
-#define	TUNGCAP		_IOR('t', 96, struct tun_capabilities)
-#define	TUNDCAP		_IO('t', 96)
-
 #endif /* _NET_IF_TUN_H_ */