1 /* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */ 2 /* Copyright 2019, 2020 Cloudflare */ 3 4 #include <stdbool.h> 5 #include <stddef.h> 6 #include <stdint.h> 7 #include <string.h> 8 9 #include <linux/if_ether.h> 10 #include <linux/in.h> 11 #include <linux/ip.h> 12 #include <linux/ipv6.h> 13 #include <linux/udp.h> 14 15 /* offsetof() is used in static asserts, and the libbpf-redefined CO-RE 16 * friendly version breaks compilation for older clang versions <= 15 17 * when invoked in a static assert. Restore original here. 18 */ 19 #ifdef offsetof 20 #undef offsetof 21 #define offsetof(type, member) __builtin_offsetof(type, member) 22 #endif 23 24 struct gre_base_hdr { 25 uint16_t flags; 26 uint16_t protocol; 27 } __attribute__((packed)); 28 29 struct guehdr { 30 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ 31 uint8_t hlen : 5, control : 1, variant : 2; 32 #else 33 uint8_t variant : 2, control : 1, hlen : 5; 34 #endif 35 uint8_t proto_ctype; 36 uint16_t flags; 37 }; 38 39 struct unigue { 40 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ 41 uint8_t _r : 2, last_hop_gre : 1, forward_syn : 1, version : 4; 42 #else 43 uint8_t version : 4, forward_syn : 1, last_hop_gre : 1, _r : 2; 44 #endif 45 uint8_t reserved; 46 uint8_t next_hop; 47 uint8_t hop_count; 48 // Next hops go here 49 } __attribute__((packed)); 50 51 typedef struct { 52 struct ethhdr eth; 53 struct iphdr ip; 54 struct gre_base_hdr gre; 55 } __attribute__((packed)) encap_gre_t; 56 57 typedef struct { 58 struct ethhdr eth; 59 struct iphdr ip; 60 struct udphdr udp; 61 struct guehdr gue; 62 struct unigue unigue; 63 } __attribute__((packed)) encap_headers_t; 64