1 files changed, 98 insertions, 51 deletions

diff --git a/include/net/gre.h b/include/net/gre.h
index 57e4afdf7879..ccd293203284 100644
--- a/include/net/gre.h
+++ b/include/net/gre.h
@@ -1,9 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef __LINUX_GRE_H
 #define __LINUX_GRE_H
 
 #include <linux/skbuff.h>
 #include <net/ip_tunnels.h>
 
+struct gre_base_hdr {
+	__be16 flags;
+	__be16 protocol;
+} __packed;
+
+struct gre_full_hdr {
+	struct gre_base_hdr fixed_header;
+	__be16 csum;
+	__be16 reserved1;
+	__be32 key;
+	__be32 seq;
+} __packed;
+#define GRE_HEADER_SECTION 4
+
 #define GREPROTO_CISCO		0
 #define GREPROTO_PPTP		1
 #define GREPROTO_MAX		2
@@ -14,87 +29,119 @@ struct gre_protocol {
 	void (*err_handler)(struct sk_buff *skb, u32 info);
 };
 
-struct gre_base_hdr {
-	__be16 flags;
-	__be16 protocol;
-};
-#define GRE_HEADER_SECTION 4
-
 int gre_add_protocol(const struct gre_protocol *proto, u8 version);
 int gre_del_protocol(const struct gre_protocol *proto, u8 version);
 
-struct gre_cisco_protocol {
-	int (*handler)(struct sk_buff *skb, const struct tnl_ptk_info *tpi);
-	int (*err_handler)(struct sk_buff *skb, u32 info,
-			   const struct tnl_ptk_info *tpi);
-	u8 priority;
-};
-
-int gre_cisco_register(struct gre_cisco_protocol *proto);
-int gre_cisco_unregister(struct gre_cisco_protocol *proto);
+struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
+				       u8 name_assign_type);
+int gre_parse_header(struct sk_buff *skb, struct tnl_ptk_info *tpi,
+		     bool *csum_err, __be16 proto, int nhs);
 
-int gre_offload_init(void);
-void gre_offload_exit(void);
+static inline bool netif_is_gretap(const struct net_device *dev)
+{
+	return dev->rtnl_link_ops &&
+	       !strcmp(dev->rtnl_link_ops->kind, "gretap");
+}
 
-void gre_build_header(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
-		      int hdr_len);
-struct sk_buff *gre_handle_offloads(struct sk_buff *skb, bool gre_csum);
+static inline bool netif_is_ip6gretap(const struct net_device *dev)
+{
+	return dev->rtnl_link_ops &&
+	       !strcmp(dev->rtnl_link_ops->kind, "ip6gretap");
+}
 
-static inline int ip_gre_calc_hlen(__be16 o_flags)
+static inline int gre_calc_hlen(const unsigned long *o_flags)
 {
 	int addend = 4;
 
-	if (o_flags&TUNNEL_CSUM)
+	if (test_bit(IP_TUNNEL_CSUM_BIT, o_flags))
 		addend += 4;
-	if (o_flags&TUNNEL_KEY)
+	if (test_bit(IP_TUNNEL_KEY_BIT, o_flags))
 		addend += 4;
-	if (o_flags&TUNNEL_SEQ)
+	if (test_bit(IP_TUNNEL_SEQ_BIT, o_flags))
 		addend += 4;
 	return addend;
 }
 
-static inline __be16 gre_flags_to_tnl_flags(__be16 flags)
+static inline void gre_flags_to_tnl_flags(unsigned long *dst, __be16 flags)
 {
-	__be16 tflags = 0;
-
-	if (flags & GRE_CSUM)
-		tflags |= TUNNEL_CSUM;
-	if (flags & GRE_ROUTING)
-		tflags |= TUNNEL_ROUTING;
-	if (flags & GRE_KEY)
-		tflags |= TUNNEL_KEY;
-	if (flags & GRE_SEQ)
-		tflags |= TUNNEL_SEQ;
-	if (flags & GRE_STRICT)
-		tflags |= TUNNEL_STRICT;
-	if (flags & GRE_REC)
-		tflags |= TUNNEL_REC;
-	if (flags & GRE_VERSION)
-		tflags |= TUNNEL_VERSION;
-
-	return tflags;
+	IP_TUNNEL_DECLARE_FLAGS(res) = { };
+
+	__assign_bit(IP_TUNNEL_CSUM_BIT, res, flags & GRE_CSUM);
+	__assign_bit(IP_TUNNEL_ROUTING_BIT, res, flags & GRE_ROUTING);
+	__assign_bit(IP_TUNNEL_KEY_BIT, res, flags & GRE_KEY);
+	__assign_bit(IP_TUNNEL_SEQ_BIT, res, flags & GRE_SEQ);
+	__assign_bit(IP_TUNNEL_STRICT_BIT, res, flags & GRE_STRICT);
+	__assign_bit(IP_TUNNEL_REC_BIT, res, flags & GRE_REC);
+	__assign_bit(IP_TUNNEL_VERSION_BIT, res, flags & GRE_VERSION);
+
+	ip_tunnel_flags_copy(dst, res);
 }
 
-static inline __be16 tnl_flags_to_gre_flags(__be16 tflags)
+static inline __be16 gre_tnl_flags_to_gre_flags(const unsigned long *tflags)
 {
 	__be16 flags = 0;
 
-	if (tflags & TUNNEL_CSUM)
+	if (test_bit(IP_TUNNEL_CSUM_BIT, tflags))
 		flags |= GRE_CSUM;
-	if (tflags & TUNNEL_ROUTING)
+	if (test_bit(IP_TUNNEL_ROUTING_BIT, tflags))
 		flags |= GRE_ROUTING;
-	if (tflags & TUNNEL_KEY)
+	if (test_bit(IP_TUNNEL_KEY_BIT, tflags))
 		flags |= GRE_KEY;
-	if (tflags & TUNNEL_SEQ)
+	if (test_bit(IP_TUNNEL_SEQ_BIT, tflags))
 		flags |= GRE_SEQ;
-	if (tflags & TUNNEL_STRICT)
+	if (test_bit(IP_TUNNEL_STRICT_BIT, tflags))
 		flags |= GRE_STRICT;
-	if (tflags & TUNNEL_REC)
+	if (test_bit(IP_TUNNEL_REC_BIT, tflags))
 		flags |= GRE_REC;
-	if (tflags & TUNNEL_VERSION)
+	if (test_bit(IP_TUNNEL_VERSION_BIT, tflags))
 		flags |= GRE_VERSION;
 
 	return flags;
 }
 
+static inline void gre_build_header(struct sk_buff *skb, int hdr_len,
+				    const unsigned long *flags, __be16 proto,
+				    __be32 key, __be32 seq)
+{
+	IP_TUNNEL_DECLARE_FLAGS(cond) = { };
+	struct gre_base_hdr *greh;
+
+	skb_push(skb, hdr_len);
+
+	skb_set_inner_protocol(skb, proto);
+	skb_reset_transport_header(skb);
+	greh = (struct gre_base_hdr *)skb->data;
+	greh->flags = gre_tnl_flags_to_gre_flags(flags);
+	greh->protocol = proto;
+
+	__set_bit(IP_TUNNEL_KEY_BIT, cond);
+	__set_bit(IP_TUNNEL_CSUM_BIT, cond);
+	__set_bit(IP_TUNNEL_SEQ_BIT, cond);
+
+	if (ip_tunnel_flags_intersect(flags, cond)) {
+		__be32 *ptr = (__be32 *)(((u8 *)greh) + hdr_len - 4);
+
+		if (test_bit(IP_TUNNEL_SEQ_BIT, flags)) {
+			*ptr = seq;
+			ptr--;
+		}
+		if (test_bit(IP_TUNNEL_KEY_BIT, flags)) {
+			*ptr = key;
+			ptr--;
+		}
+		if (test_bit(IP_TUNNEL_CSUM_BIT, flags) &&
+		    !(skb_shinfo(skb)->gso_type &
+		      (SKB_GSO_GRE | SKB_GSO_GRE_CSUM))) {
+			*ptr = 0;
+			if (skb->ip_summed == CHECKSUM_PARTIAL) {
+				*(__sum16 *)ptr = csum_fold(lco_csum(skb));
+			} else {
+				skb->ip_summed = CHECKSUM_PARTIAL;
+				skb->csum_start = skb_transport_header(skb) - skb->head;
+				skb->csum_offset = sizeof(*greh);
+			}
+		}
+	}
+}
+
 #endif