From: jan <jan@openbsd.org>
Date: Thu, 27 Jul 2023 20:21:25 +0000 (+0000)
Subject: Fix inline vlan-tag handling of forwarded LRO packets from ix(4)
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=d1dd674394e26782b4b514c396291cce34071e5c;p=openbsd

Fix inline vlan-tag handling of forwarded LRO packets from ix(4)

Implement vlan-tag parsing ether_extract_header() to use this information
to adjust the MSS calculation of LRO packets.

pointed out by mbuhl and bluhm

with tweaks from bluhm

ok bluhm@
---

diff --git a/sys/dev/pci/if_ix.c b/sys/dev/pci/if_ix.c
index 3610ed92a26..80df360e06e 100644
--- a/sys/dev/pci/if_ix.c
+++ b/sys/dev/pci/if_ix.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_ix.c,v 1.200 2023/07/18 16:01:20 bluhm Exp $	*/
+/*	$OpenBSD: if_ix.c,v 1.201 2023/07/27 20:21:25 jan Exp $	*/
 
 /******************************************************************************
 
@@ -3275,6 +3275,10 @@ ixgbe_rxeof(struct rx_ring *rxr)
 				/* Calculate header size. */
 				ether_extract_headers(sendmp, &ext);
 				hdrlen = sizeof(*ext.eh);
+#if NVLAN > 0
+				if (ext.evh)
+					hdrlen += ETHER_VLAN_ENCAP_LEN;
+#endif
 				if (ext.ip4)
 					hdrlen += ext.ip4->ip_hl << 2;
 				if (ext.ip6)
diff --git a/sys/net/if_ethersubr.c b/sys/net/if_ethersubr.c
index 20f7a9aee2e..a77a0d6543c 100644
--- a/sys/net/if_ethersubr.c
+++ b/sys/net/if_ethersubr.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_ethersubr.c,v 1.290 2023/07/06 19:46:53 kn Exp $	*/
+/*	$OpenBSD: if_ethersubr.c,v 1.291 2023/07/27 20:21:25 jan Exp $	*/
 /*	$NetBSD: if_ethersubr.c,v 1.19 1996/05/07 02:40:30 thorpej Exp $	*/
 
 /*
@@ -1040,6 +1040,7 @@ ether_extract_headers(struct mbuf *mp, struct ether_extracted *ext)
 	uint64_t	 hlen;
 	int		 hoff;
 	uint8_t		 ipproto;
+	uint16_t	 ether_type;
 
 	/* Return NULL if header was not recognized. */
 	memset(ext, 0, sizeof(*ext));
@@ -1048,9 +1049,20 @@ ether_extract_headers(struct mbuf *mp, struct ether_extracted *ext)
 		return;
 
 	ext->eh = mtod(mp, struct ether_header *);
-	switch (ntohs(ext->eh->ether_type)) {
+	ether_type = ntohs(ext->eh->ether_type);
+	hlen = sizeof(*ext->eh);
+
+#if NVLAN > 0
+	if (ether_type == ETHERTYPE_VLAN) {
+		ext->evh = mtod(mp, struct ether_vlan_header *);
+		ether_type = ntohs(ext->evh->evl_proto);
+		hlen = sizeof(*ext->evh);
+	}
+#endif
+
+	switch (ether_type) {
 	case ETHERTYPE_IP:
-		m = m_getptr(mp, sizeof(*ext->eh), &hoff);
+		m = m_getptr(mp, hlen, &hoff);
 		if (m == NULL || m->m_len - hoff < sizeof(*ext->ip4))
 			return;
 		ext->ip4 = (struct ip *)(mtod(m, caddr_t) + hoff);
@@ -1064,7 +1076,7 @@ ether_extract_headers(struct mbuf *mp, struct ether_extracted *ext)
 		break;
 #ifdef INET6
 	case ETHERTYPE_IPV6:
-		m = m_getptr(mp, sizeof(*ext->eh), &hoff);
+		m = m_getptr(mp, hlen, &hoff);
 		if (m == NULL || m->m_len - hoff < sizeof(*ext->ip6))
 			return;
 		ext->ip6 = (struct ip6_hdr *)(mtod(m, caddr_t) + hoff);
diff --git a/sys/netinet/if_ether.h b/sys/netinet/if_ether.h
index 9ff5baeaed1..ed28944e721 100644
--- a/sys/netinet/if_ether.h
+++ b/sys/netinet/if_ether.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_ether.h,v 1.89 2023/07/06 19:46:53 kn Exp $	*/
+/*	$OpenBSD: if_ether.h,v 1.90 2023/07/27 20:21:25 jan Exp $	*/
 /*	$NetBSD: if_ether.h,v 1.22 1996/05/11 13:00:00 mycroft Exp $	*/
 
 /*
@@ -301,11 +301,12 @@ uint64_t	ether_addr_to_e64(const struct ether_addr *);
 void		ether_e64_to_addr(struct ether_addr *, uint64_t);
 
 struct ether_extracted {
-	struct ether_header	*eh;
-	struct ip		*ip4;
-	struct ip6_hdr		*ip6;
-	struct tcphdr		*tcp;
-	struct udphdr		*udp;
+	struct ether_header		*eh;
+	struct ether_vlan_header	*evh;
+	struct ip			*ip4;
+	struct ip6_hdr			*ip6;
+	struct tcphdr			*tcp;
+	struct udphdr			*udp;
 };
 
 void ether_extract_headers(struct mbuf *, struct ether_extracted *);