projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 00959ade DK |
2 | #ifndef __LINUX_GRE_H |
| 3 | #define __LINUX_GRE_H | |
| 4 | ||
| 5 | #include <linux/skbuff.h> | |
| c5441932 | 6 | #include <net/ip_tunnels.h> |
| 00959ade | 7 | |
| 9f57c67c PS |
8 | struct gre_base_hdr { |
| 9 | __be16 flags; | |
| 10 | __be16 protocol; | |
| ab10dccb GF |
11 | } __packed; |
| 12 | ||
| 13 | struct gre_full_hdr { | |
| 14 | struct gre_base_hdr fixed_header; | |
| 15 | __be16 csum; | |
| 16 | __be16 reserved1; | |
| 17 | __be32 key; | |
| 18 | __be32 seq; | |
| 19 | } __packed; | |
| 9f57c67c PS |
20 | #define GRE_HEADER_SECTION 4 |
| 21 | ||
| 00959ade DK |
22 | #define GREPROTO_CISCO 0 |
| 23 | #define GREPROTO_PPTP 1 | |
| 24 | #define GREPROTO_MAX 2 | |
| bda7bb46 | 25 | #define GRE_IP_PROTO_MAX 2 |
| 00959ade DK |
26 | |
| 27 | struct gre_protocol { | |
| 28 | int (*handler)(struct sk_buff *skb); | |
| 29 | void (*err_handler)(struct sk_buff *skb, u32 info); | |
| 30 | }; | |
| 31 | ||
| 32 | int gre_add_protocol(const struct gre_protocol *proto, u8 version); | |
| 33 | int gre_del_protocol(const struct gre_protocol *proto, u8 version); | |
| 34 | ||
| b2acd1dc PS |
35 | struct net_device *gretap_fb_dev_create(struct net *net, const char *name, |
| 36 | u8 name_assign_type); | |
| 95f5c64c | 37 | int gre_parse_header(struct sk_buff *skb, struct tnl_ptk_info *tpi, |
| e582615a | 38 | bool *csum_err, __be16 proto, int nhs); |
| 95f5c64c | 39 | |
| d1b2a6c4 PM |
40 | bool is_gretap_dev(const struct net_device *dev); |
| 41 | bool is_ip6gretap_dev(const struct net_device *dev); | |
| 42 | ||
| 95f5c64c TH |
43 | static inline int gre_calc_hlen(__be16 o_flags) |
| 44 | { | |
| 45 | int addend = 4; | |
| 46 | ||
| 47 | if (o_flags & TUNNEL_CSUM) | |
| 48 | addend += 4; | |
| 49 | if (o_flags & TUNNEL_KEY) | |
| 50 | addend += 4; | |
| 51 | if (o_flags & TUNNEL_SEQ) | |
| 52 | addend += 4; | |
| 53 | return addend; | |
| 54 | } | |
| 55 | ||
| 56 | static inline __be16 gre_flags_to_tnl_flags(__be16 flags) | |
| 57 | { | |
| 58 | __be16 tflags = 0; | |
| 59 | ||
| 60 | if (flags & GRE_CSUM) | |
| 61 | tflags |= TUNNEL_CSUM; | |
| 62 | if (flags & GRE_ROUTING) | |
| 63 | tflags |= TUNNEL_ROUTING; | |
| 64 | if (flags & GRE_KEY) | |
| 65 | tflags |= TUNNEL_KEY; | |
| 66 | if (flags & GRE_SEQ) | |
| 67 | tflags |= TUNNEL_SEQ; | |
| 68 | if (flags & GRE_STRICT) | |
| 69 | tflags |= TUNNEL_STRICT; | |
| 70 | if (flags & GRE_REC) | |
| 71 | tflags |= TUNNEL_REC; | |
| 72 | if (flags & GRE_VERSION) | |
| 73 | tflags |= TUNNEL_VERSION; | |
| 74 | ||
| 75 | return tflags; | |
| 76 | } | |
| 77 | ||
| 78 | static inline __be16 gre_tnl_flags_to_gre_flags(__be16 tflags) | |
| 79 | { | |
| 80 | __be16 flags = 0; | |
| 81 | ||
| 82 | if (tflags & TUNNEL_CSUM) | |
| 83 | flags |= GRE_CSUM; | |
| 84 | if (tflags & TUNNEL_ROUTING) | |
| 85 | flags |= GRE_ROUTING; | |
| 86 | if (tflags & TUNNEL_KEY) | |
| 87 | flags |= GRE_KEY; | |
| 88 | if (tflags & TUNNEL_SEQ) | |
| 89 | flags |= GRE_SEQ; | |
| 90 | if (tflags & TUNNEL_STRICT) | |
| 91 | flags |= GRE_STRICT; | |
| 92 | if (tflags & TUNNEL_REC) | |
| 93 | flags |= GRE_REC; | |
| 94 | if (tflags & TUNNEL_VERSION) | |
| 95 | flags |= GRE_VERSION; | |
| 96 | ||
| 97 | return flags; | |
| 98 | } | |
| 99 | ||
| 182a352d TH |
100 | static inline __sum16 gre_checksum(struct sk_buff *skb) |
| 101 | { | |
| 102 | __wsum csum; | |
| 103 | ||
| 104 | if (skb->ip_summed == CHECKSUM_PARTIAL) | |
| 105 | csum = lco_csum(skb); | |
| 106 | else | |
| 107 | csum = skb_checksum(skb, 0, skb->len, 0); | |
| 108 | return csum_fold(csum); | |
| 109 | } | |
| 110 | ||
| 111 | static inline void gre_build_header(struct sk_buff *skb, int hdr_len, | |
| 112 | __be16 flags, __be16 proto, | |
| 113 | __be32 key, __be32 seq) | |
| 114 | { | |
| 115 | struct gre_base_hdr *greh; | |
| 116 | ||
| 117 | skb_push(skb, hdr_len); | |
| 118 | ||
| 3d7b3320 | 119 | skb_set_inner_protocol(skb, proto); |
| 182a352d TH |
120 | skb_reset_transport_header(skb); |
| 121 | greh = (struct gre_base_hdr *)skb->data; | |
| 122 | greh->flags = gre_tnl_flags_to_gre_flags(flags); | |
| 123 | greh->protocol = proto; | |
| 124 | ||
| 125 | if (flags & (TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_SEQ)) { | |
| 126 | __be32 *ptr = (__be32 *)(((u8 *)greh) + hdr_len - 4); | |
| 127 | ||
| 128 | if (flags & TUNNEL_SEQ) { | |
| 129 | *ptr = seq; | |
| 130 | ptr--; | |
| 131 | } | |
| 132 | if (flags & TUNNEL_KEY) { | |
| 133 | *ptr = key; | |
| 134 | ptr--; | |
| 135 | } | |
| 136 | if (flags & TUNNEL_CSUM && | |
| 137 | !(skb_shinfo(skb)->gso_type & | |
| 138 | (SKB_GSO_GRE | SKB_GSO_GRE_CSUM))) { | |
| 139 | *ptr = 0; | |
| 140 | *(__sum16 *)ptr = gre_checksum(skb); | |
| 141 | } | |
| 142 | } | |
| 143 | } | |
| 144 | ||
| 00959ade | 145 | #endif |