839 lines
20 KiB
C
839 lines
20 KiB
C
// SPDX-License-Identifier: GPL-2.0
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// Copyright (c) 2017 Facebook
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#include <stddef.h>
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#include <stdbool.h>
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#include <string.h>
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#include <linux/pkt_cls.h>
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#include <linux/bpf.h>
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#include <linux/in.h>
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#include <linux/if_ether.h>
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#include <linux/ip.h>
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#include <linux/ipv6.h>
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#include <linux/icmp.h>
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#include <linux/icmpv6.h>
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#include <linux/tcp.h>
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#include <linux/udp.h>
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#include <bpf/bpf_helpers.h>
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#include <bpf/bpf_endian.h>
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static __always_inline __u32 rol32(__u32 word, unsigned int shift)
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{
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return (word << shift) | (word >> ((-shift) & 31));
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}
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/* copy paste of jhash from kernel sources to make sure llvm
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* can compile it into valid sequence of bpf instructions
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*/
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#define __jhash_mix(a, b, c) \
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{ \
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a -= c; a ^= rol32(c, 4); c += b; \
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b -= a; b ^= rol32(a, 6); a += c; \
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c -= b; c ^= rol32(b, 8); b += a; \
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a -= c; a ^= rol32(c, 16); c += b; \
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b -= a; b ^= rol32(a, 19); a += c; \
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c -= b; c ^= rol32(b, 4); b += a; \
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}
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#define __jhash_final(a, b, c) \
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{ \
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c ^= b; c -= rol32(b, 14); \
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a ^= c; a -= rol32(c, 11); \
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b ^= a; b -= rol32(a, 25); \
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c ^= b; c -= rol32(b, 16); \
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a ^= c; a -= rol32(c, 4); \
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b ^= a; b -= rol32(a, 14); \
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c ^= b; c -= rol32(b, 24); \
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}
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#define JHASH_INITVAL 0xdeadbeef
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typedef unsigned int u32;
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static __noinline
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u32 jhash(const void *key, u32 length, u32 initval)
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{
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u32 a, b, c;
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const unsigned char *k = key;
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a = b = c = JHASH_INITVAL + length + initval;
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while (length > 12) {
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a += *(u32 *)(k);
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b += *(u32 *)(k + 4);
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c += *(u32 *)(k + 8);
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__jhash_mix(a, b, c);
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length -= 12;
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k += 12;
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}
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switch (length) {
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case 12: c += (u32)k[11]<<24;
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case 11: c += (u32)k[10]<<16;
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case 10: c += (u32)k[9]<<8;
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case 9: c += k[8];
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case 8: b += (u32)k[7]<<24;
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case 7: b += (u32)k[6]<<16;
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case 6: b += (u32)k[5]<<8;
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case 5: b += k[4];
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case 4: a += (u32)k[3]<<24;
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case 3: a += (u32)k[2]<<16;
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case 2: a += (u32)k[1]<<8;
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case 1: a += k[0];
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__jhash_final(a, b, c);
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case 0: /* Nothing left to add */
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break;
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}
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return c;
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}
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__noinline
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u32 __jhash_nwords(u32 a, u32 b, u32 c, u32 initval)
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{
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a += initval;
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b += initval;
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c += initval;
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__jhash_final(a, b, c);
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return c;
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}
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__noinline
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u32 jhash_2words(u32 a, u32 b, u32 initval)
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{
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return __jhash_nwords(a, b, 0, initval + JHASH_INITVAL + (2 << 2));
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}
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struct flow_key {
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union {
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__be32 src;
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__be32 srcv6[4];
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};
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union {
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__be32 dst;
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__be32 dstv6[4];
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};
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union {
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__u32 ports;
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__u16 port16[2];
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};
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__u8 proto;
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};
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struct packet_description {
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struct flow_key flow;
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__u8 flags;
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};
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struct ctl_value {
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union {
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__u64 value;
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__u32 ifindex;
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__u8 mac[6];
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};
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};
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struct vip_definition {
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union {
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__be32 vip;
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__be32 vipv6[4];
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};
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__u16 port;
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__u16 family;
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__u8 proto;
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};
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struct vip_meta {
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__u32 flags;
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__u32 vip_num;
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};
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struct real_pos_lru {
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__u32 pos;
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__u64 atime;
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};
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struct real_definition {
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union {
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__be32 dst;
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__be32 dstv6[4];
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};
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__u8 flags;
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};
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struct lb_stats {
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__u64 v2;
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__u64 v1;
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};
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struct {
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__uint(type, BPF_MAP_TYPE_HASH);
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__uint(max_entries, 512);
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__type(key, struct vip_definition);
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__type(value, struct vip_meta);
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} vip_map SEC(".maps");
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struct {
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__uint(type, BPF_MAP_TYPE_LRU_HASH);
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__uint(max_entries, 300);
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__uint(map_flags, 1U << 1);
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__type(key, struct flow_key);
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__type(value, struct real_pos_lru);
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} lru_cache SEC(".maps");
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struct {
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__uint(type, BPF_MAP_TYPE_ARRAY);
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__uint(max_entries, 12 * 655);
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__type(key, __u32);
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__type(value, __u32);
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} ch_rings SEC(".maps");
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struct {
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__uint(type, BPF_MAP_TYPE_ARRAY);
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__uint(max_entries, 40);
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__type(key, __u32);
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__type(value, struct real_definition);
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} reals SEC(".maps");
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struct {
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__uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
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__uint(max_entries, 515);
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__type(key, __u32);
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__type(value, struct lb_stats);
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} stats SEC(".maps");
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struct {
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__uint(type, BPF_MAP_TYPE_ARRAY);
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__uint(max_entries, 16);
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__type(key, __u32);
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__type(value, struct ctl_value);
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} ctl_array SEC(".maps");
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struct eth_hdr {
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unsigned char eth_dest[6];
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unsigned char eth_source[6];
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unsigned short eth_proto;
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};
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static __noinline __u64 calc_offset(bool is_ipv6, bool is_icmp)
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{
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__u64 off = sizeof(struct eth_hdr);
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if (is_ipv6) {
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off += sizeof(struct ipv6hdr);
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if (is_icmp)
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off += sizeof(struct icmp6hdr) + sizeof(struct ipv6hdr);
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} else {
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off += sizeof(struct iphdr);
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if (is_icmp)
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off += sizeof(struct icmphdr) + sizeof(struct iphdr);
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}
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return off;
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}
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static __attribute__ ((noinline))
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bool parse_udp(void *data, void *data_end,
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bool is_ipv6, struct packet_description *pckt)
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{
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bool is_icmp = !((pckt->flags & (1 << 0)) == 0);
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__u64 off = calc_offset(is_ipv6, is_icmp);
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struct udphdr *udp;
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udp = data + off;
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if (udp + 1 > data_end)
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return false;
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if (!is_icmp) {
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pckt->flow.port16[0] = udp->source;
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pckt->flow.port16[1] = udp->dest;
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} else {
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pckt->flow.port16[0] = udp->dest;
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pckt->flow.port16[1] = udp->source;
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}
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return true;
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}
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static __attribute__ ((noinline))
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bool parse_tcp(void *data, void *data_end,
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bool is_ipv6, struct packet_description *pckt)
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{
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bool is_icmp = !((pckt->flags & (1 << 0)) == 0);
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__u64 off = calc_offset(is_ipv6, is_icmp);
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struct tcphdr *tcp;
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tcp = data + off;
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if (tcp + 1 > data_end)
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return false;
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if (tcp->syn)
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pckt->flags |= (1 << 1);
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if (!is_icmp) {
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pckt->flow.port16[0] = tcp->source;
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pckt->flow.port16[1] = tcp->dest;
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} else {
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pckt->flow.port16[0] = tcp->dest;
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pckt->flow.port16[1] = tcp->source;
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}
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return true;
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}
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static __attribute__ ((noinline))
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bool encap_v6(struct xdp_md *xdp, struct ctl_value *cval,
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struct packet_description *pckt,
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struct real_definition *dst, __u32 pkt_bytes)
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{
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struct eth_hdr *new_eth;
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struct eth_hdr *old_eth;
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struct ipv6hdr *ip6h;
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__u32 ip_suffix;
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void *data_end;
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void *data;
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if (bpf_xdp_adjust_head(xdp, 0 - (int)sizeof(struct ipv6hdr)))
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return false;
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data = (void *)(long)xdp->data;
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data_end = (void *)(long)xdp->data_end;
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new_eth = data;
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ip6h = data + sizeof(struct eth_hdr);
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old_eth = data + sizeof(struct ipv6hdr);
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if (new_eth + 1 > data_end ||
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old_eth + 1 > data_end || ip6h + 1 > data_end)
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return false;
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memcpy(new_eth->eth_dest, cval->mac, 6);
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memcpy(new_eth->eth_source, old_eth->eth_dest, 6);
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new_eth->eth_proto = 56710;
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ip6h->version = 6;
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ip6h->priority = 0;
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memset(ip6h->flow_lbl, 0, sizeof(ip6h->flow_lbl));
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ip6h->nexthdr = IPPROTO_IPV6;
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ip_suffix = pckt->flow.srcv6[3] ^ pckt->flow.port16[0];
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ip6h->payload_len =
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bpf_htons(pkt_bytes + sizeof(struct ipv6hdr));
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ip6h->hop_limit = 4;
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ip6h->saddr.in6_u.u6_addr32[0] = 1;
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ip6h->saddr.in6_u.u6_addr32[1] = 2;
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ip6h->saddr.in6_u.u6_addr32[2] = 3;
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ip6h->saddr.in6_u.u6_addr32[3] = ip_suffix;
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memcpy(ip6h->daddr.in6_u.u6_addr32, dst->dstv6, 16);
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return true;
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}
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static __attribute__ ((noinline))
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bool encap_v4(struct xdp_md *xdp, struct ctl_value *cval,
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struct packet_description *pckt,
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struct real_definition *dst, __u32 pkt_bytes)
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{
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__u32 ip_suffix = bpf_ntohs(pckt->flow.port16[0]);
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struct eth_hdr *new_eth;
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struct eth_hdr *old_eth;
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__u16 *next_iph_u16;
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struct iphdr *iph;
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__u32 csum = 0;
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void *data_end;
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void *data;
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ip_suffix <<= 15;
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ip_suffix ^= pckt->flow.src;
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if (bpf_xdp_adjust_head(xdp, 0 - (int)sizeof(struct iphdr)))
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return false;
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data = (void *)(long)xdp->data;
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data_end = (void *)(long)xdp->data_end;
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new_eth = data;
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iph = data + sizeof(struct eth_hdr);
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old_eth = data + sizeof(struct iphdr);
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if (new_eth + 1 > data_end ||
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old_eth + 1 > data_end || iph + 1 > data_end)
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return false;
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memcpy(new_eth->eth_dest, cval->mac, 6);
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memcpy(new_eth->eth_source, old_eth->eth_dest, 6);
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new_eth->eth_proto = 8;
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iph->version = 4;
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iph->ihl = 5;
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iph->frag_off = 0;
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iph->protocol = IPPROTO_IPIP;
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iph->check = 0;
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iph->tos = 1;
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iph->tot_len = bpf_htons(pkt_bytes + sizeof(struct iphdr));
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/* don't update iph->daddr, since it will overwrite old eth_proto
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* and multiple iterations of bpf_prog_run() will fail
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*/
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iph->saddr = ((0xFFFF0000 & ip_suffix) | 4268) ^ dst->dst;
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iph->ttl = 4;
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next_iph_u16 = (__u16 *) iph;
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#pragma clang loop unroll(full)
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for (int i = 0; i < sizeof(struct iphdr) >> 1; i++)
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csum += *next_iph_u16++;
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iph->check = ~((csum & 0xffff) + (csum >> 16));
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if (bpf_xdp_adjust_head(xdp, (int)sizeof(struct iphdr)))
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return false;
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return true;
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}
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static __attribute__ ((noinline))
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bool decap_v6(struct xdp_md *xdp, void **data, void **data_end, bool inner_v4)
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{
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struct eth_hdr *new_eth;
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struct eth_hdr *old_eth;
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old_eth = *data;
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new_eth = *data + sizeof(struct ipv6hdr);
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memcpy(new_eth->eth_source, old_eth->eth_source, 6);
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memcpy(new_eth->eth_dest, old_eth->eth_dest, 6);
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if (inner_v4)
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new_eth->eth_proto = 8;
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else
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new_eth->eth_proto = 56710;
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if (bpf_xdp_adjust_head(xdp, (int)sizeof(struct ipv6hdr)))
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return false;
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*data = (void *)(long)xdp->data;
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*data_end = (void *)(long)xdp->data_end;
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return true;
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}
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static __attribute__ ((noinline))
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bool decap_v4(struct xdp_md *xdp, void **data, void **data_end)
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{
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struct eth_hdr *new_eth;
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struct eth_hdr *old_eth;
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old_eth = *data;
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new_eth = *data + sizeof(struct iphdr);
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memcpy(new_eth->eth_source, old_eth->eth_source, 6);
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memcpy(new_eth->eth_dest, old_eth->eth_dest, 6);
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new_eth->eth_proto = 8;
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if (bpf_xdp_adjust_head(xdp, (int)sizeof(struct iphdr)))
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return false;
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*data = (void *)(long)xdp->data;
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*data_end = (void *)(long)xdp->data_end;
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return true;
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}
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static __attribute__ ((noinline))
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int swap_mac_and_send(void *data, void *data_end)
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{
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unsigned char tmp_mac[6];
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struct eth_hdr *eth;
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eth = data;
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memcpy(tmp_mac, eth->eth_source, 6);
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memcpy(eth->eth_source, eth->eth_dest, 6);
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memcpy(eth->eth_dest, tmp_mac, 6);
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return XDP_TX;
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}
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static __attribute__ ((noinline))
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int send_icmp_reply(void *data, void *data_end)
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{
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struct icmphdr *icmp_hdr;
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__u16 *next_iph_u16;
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__u32 tmp_addr = 0;
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struct iphdr *iph;
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__u32 csum1 = 0;
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__u32 csum = 0;
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__u64 off = 0;
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if (data + sizeof(struct eth_hdr)
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+ sizeof(struct iphdr) + sizeof(struct icmphdr) > data_end)
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return XDP_DROP;
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off += sizeof(struct eth_hdr);
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iph = data + off;
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off += sizeof(struct iphdr);
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icmp_hdr = data + off;
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icmp_hdr->type = 0;
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icmp_hdr->checksum += 0x0007;
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iph->ttl = 4;
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tmp_addr = iph->daddr;
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iph->daddr = iph->saddr;
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iph->saddr = tmp_addr;
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iph->check = 0;
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next_iph_u16 = (__u16 *) iph;
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#pragma clang loop unroll(full)
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for (int i = 0; i < sizeof(struct iphdr) >> 1; i++)
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csum += *next_iph_u16++;
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iph->check = ~((csum & 0xffff) + (csum >> 16));
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return swap_mac_and_send(data, data_end);
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}
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static __attribute__ ((noinline))
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int send_icmp6_reply(void *data, void *data_end)
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{
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struct icmp6hdr *icmp_hdr;
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struct ipv6hdr *ip6h;
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__be32 tmp_addr[4];
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__u64 off = 0;
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if (data + sizeof(struct eth_hdr)
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+ sizeof(struct ipv6hdr) + sizeof(struct icmp6hdr) > data_end)
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return XDP_DROP;
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off += sizeof(struct eth_hdr);
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ip6h = data + off;
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off += sizeof(struct ipv6hdr);
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icmp_hdr = data + off;
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icmp_hdr->icmp6_type = 129;
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icmp_hdr->icmp6_cksum -= 0x0001;
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ip6h->hop_limit = 4;
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memcpy(tmp_addr, ip6h->saddr.in6_u.u6_addr32, 16);
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memcpy(ip6h->saddr.in6_u.u6_addr32, ip6h->daddr.in6_u.u6_addr32, 16);
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memcpy(ip6h->daddr.in6_u.u6_addr32, tmp_addr, 16);
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return swap_mac_and_send(data, data_end);
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}
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static __attribute__ ((noinline))
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int parse_icmpv6(void *data, void *data_end, __u64 off,
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struct packet_description *pckt)
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{
|
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struct icmp6hdr *icmp_hdr;
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struct ipv6hdr *ip6h;
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icmp_hdr = data + off;
|
|
if (icmp_hdr + 1 > data_end)
|
|
return XDP_DROP;
|
|
if (icmp_hdr->icmp6_type == 128)
|
|
return send_icmp6_reply(data, data_end);
|
|
if (icmp_hdr->icmp6_type != 3)
|
|
return XDP_PASS;
|
|
off += sizeof(struct icmp6hdr);
|
|
ip6h = data + off;
|
|
if (ip6h + 1 > data_end)
|
|
return XDP_DROP;
|
|
pckt->flow.proto = ip6h->nexthdr;
|
|
pckt->flags |= (1 << 0);
|
|
memcpy(pckt->flow.srcv6, ip6h->daddr.in6_u.u6_addr32, 16);
|
|
memcpy(pckt->flow.dstv6, ip6h->saddr.in6_u.u6_addr32, 16);
|
|
return -1;
|
|
}
|
|
|
|
static __attribute__ ((noinline))
|
|
int parse_icmp(void *data, void *data_end, __u64 off,
|
|
struct packet_description *pckt)
|
|
{
|
|
struct icmphdr *icmp_hdr;
|
|
struct iphdr *iph;
|
|
|
|
icmp_hdr = data + off;
|
|
if (icmp_hdr + 1 > data_end)
|
|
return XDP_DROP;
|
|
if (icmp_hdr->type == 8)
|
|
return send_icmp_reply(data, data_end);
|
|
if ((icmp_hdr->type != 3) || (icmp_hdr->code != 4))
|
|
return XDP_PASS;
|
|
off += sizeof(struct icmphdr);
|
|
iph = data + off;
|
|
if (iph + 1 > data_end)
|
|
return XDP_DROP;
|
|
if (iph->ihl != 5)
|
|
return XDP_DROP;
|
|
pckt->flow.proto = iph->protocol;
|
|
pckt->flags |= (1 << 0);
|
|
pckt->flow.src = iph->daddr;
|
|
pckt->flow.dst = iph->saddr;
|
|
return -1;
|
|
}
|
|
|
|
static __attribute__ ((noinline))
|
|
__u32 get_packet_hash(struct packet_description *pckt,
|
|
bool hash_16bytes)
|
|
{
|
|
if (hash_16bytes)
|
|
return jhash_2words(jhash(pckt->flow.srcv6, 16, 12),
|
|
pckt->flow.ports, 24);
|
|
else
|
|
return jhash_2words(pckt->flow.src, pckt->flow.ports,
|
|
24);
|
|
}
|
|
|
|
__attribute__ ((noinline))
|
|
static bool get_packet_dst(struct real_definition **real,
|
|
struct packet_description *pckt,
|
|
struct vip_meta *vip_info,
|
|
bool is_ipv6, void *lru_map)
|
|
{
|
|
struct real_pos_lru new_dst_lru = { };
|
|
bool hash_16bytes = is_ipv6;
|
|
__u32 *real_pos, hash, key;
|
|
__u64 cur_time;
|
|
|
|
if (vip_info->flags & (1 << 2))
|
|
hash_16bytes = 1;
|
|
if (vip_info->flags & (1 << 3)) {
|
|
pckt->flow.port16[0] = pckt->flow.port16[1];
|
|
memset(pckt->flow.srcv6, 0, 16);
|
|
}
|
|
hash = get_packet_hash(pckt, hash_16bytes);
|
|
if (hash != 0x358459b7 /* jhash of ipv4 packet */ &&
|
|
hash != 0x2f4bc6bb /* jhash of ipv6 packet */)
|
|
return false;
|
|
key = 2 * vip_info->vip_num + hash % 2;
|
|
real_pos = bpf_map_lookup_elem(&ch_rings, &key);
|
|
if (!real_pos)
|
|
return false;
|
|
key = *real_pos;
|
|
*real = bpf_map_lookup_elem(&reals, &key);
|
|
if (!(*real))
|
|
return false;
|
|
if (!(vip_info->flags & (1 << 1))) {
|
|
__u32 conn_rate_key = 512 + 2;
|
|
struct lb_stats *conn_rate_stats =
|
|
bpf_map_lookup_elem(&stats, &conn_rate_key);
|
|
|
|
if (!conn_rate_stats)
|
|
return true;
|
|
cur_time = bpf_ktime_get_ns();
|
|
if ((cur_time - conn_rate_stats->v2) >> 32 > 0xffFFFF) {
|
|
conn_rate_stats->v1 = 1;
|
|
conn_rate_stats->v2 = cur_time;
|
|
} else {
|
|
conn_rate_stats->v1 += 1;
|
|
if (conn_rate_stats->v1 >= 1)
|
|
return true;
|
|
}
|
|
if (pckt->flow.proto == IPPROTO_UDP)
|
|
new_dst_lru.atime = cur_time;
|
|
new_dst_lru.pos = key;
|
|
bpf_map_update_elem(lru_map, &pckt->flow, &new_dst_lru, 0);
|
|
}
|
|
return true;
|
|
}
|
|
|
|
__attribute__ ((noinline))
|
|
static void connection_table_lookup(struct real_definition **real,
|
|
struct packet_description *pckt,
|
|
void *lru_map)
|
|
{
|
|
|
|
struct real_pos_lru *dst_lru;
|
|
__u64 cur_time;
|
|
__u32 key;
|
|
|
|
dst_lru = bpf_map_lookup_elem(lru_map, &pckt->flow);
|
|
if (!dst_lru)
|
|
return;
|
|
if (pckt->flow.proto == IPPROTO_UDP) {
|
|
cur_time = bpf_ktime_get_ns();
|
|
if (cur_time - dst_lru->atime > 300000)
|
|
return;
|
|
dst_lru->atime = cur_time;
|
|
}
|
|
key = dst_lru->pos;
|
|
*real = bpf_map_lookup_elem(&reals, &key);
|
|
}
|
|
|
|
/* don't believe your eyes!
|
|
* below function has 6 arguments whereas bpf and llvm allow maximum of 5
|
|
* but since it's _static_ llvm can optimize one argument away
|
|
*/
|
|
__attribute__ ((noinline))
|
|
static int process_l3_headers_v6(struct packet_description *pckt,
|
|
__u8 *protocol, __u64 off,
|
|
__u16 *pkt_bytes, void *data,
|
|
void *data_end)
|
|
{
|
|
struct ipv6hdr *ip6h;
|
|
__u64 iph_len;
|
|
int action;
|
|
|
|
ip6h = data + off;
|
|
if (ip6h + 1 > data_end)
|
|
return XDP_DROP;
|
|
iph_len = sizeof(struct ipv6hdr);
|
|
*protocol = ip6h->nexthdr;
|
|
pckt->flow.proto = *protocol;
|
|
*pkt_bytes = bpf_ntohs(ip6h->payload_len);
|
|
off += iph_len;
|
|
if (*protocol == 45) {
|
|
return XDP_DROP;
|
|
} else if (*protocol == 59) {
|
|
action = parse_icmpv6(data, data_end, off, pckt);
|
|
if (action >= 0)
|
|
return action;
|
|
} else {
|
|
memcpy(pckt->flow.srcv6, ip6h->saddr.in6_u.u6_addr32, 16);
|
|
memcpy(pckt->flow.dstv6, ip6h->daddr.in6_u.u6_addr32, 16);
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
__attribute__ ((noinline))
|
|
static int process_l3_headers_v4(struct packet_description *pckt,
|
|
__u8 *protocol, __u64 off,
|
|
__u16 *pkt_bytes, void *data,
|
|
void *data_end)
|
|
{
|
|
struct iphdr *iph;
|
|
__u64 iph_len;
|
|
int action;
|
|
|
|
iph = data + off;
|
|
if (iph + 1 > data_end)
|
|
return XDP_DROP;
|
|
if (iph->ihl != 5)
|
|
return XDP_DROP;
|
|
*protocol = iph->protocol;
|
|
pckt->flow.proto = *protocol;
|
|
*pkt_bytes = bpf_ntohs(iph->tot_len);
|
|
off += 20;
|
|
if (iph->frag_off & 65343)
|
|
return XDP_DROP;
|
|
if (*protocol == IPPROTO_ICMP) {
|
|
action = parse_icmp(data, data_end, off, pckt);
|
|
if (action >= 0)
|
|
return action;
|
|
} else {
|
|
pckt->flow.src = iph->saddr;
|
|
pckt->flow.dst = iph->daddr;
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
__attribute__ ((noinline))
|
|
static int process_packet(void *data, __u64 off, void *data_end,
|
|
bool is_ipv6, struct xdp_md *xdp)
|
|
{
|
|
|
|
struct real_definition *dst = NULL;
|
|
struct packet_description pckt = { };
|
|
struct vip_definition vip = { };
|
|
struct lb_stats *data_stats;
|
|
struct eth_hdr *eth = data;
|
|
void *lru_map = &lru_cache;
|
|
struct vip_meta *vip_info;
|
|
__u32 lru_stats_key = 513;
|
|
__u32 mac_addr_pos = 0;
|
|
__u32 stats_key = 512;
|
|
struct ctl_value *cval;
|
|
__u16 pkt_bytes;
|
|
__u64 iph_len;
|
|
__u8 protocol;
|
|
__u32 vip_num;
|
|
int action;
|
|
|
|
if (is_ipv6)
|
|
action = process_l3_headers_v6(&pckt, &protocol, off,
|
|
&pkt_bytes, data, data_end);
|
|
else
|
|
action = process_l3_headers_v4(&pckt, &protocol, off,
|
|
&pkt_bytes, data, data_end);
|
|
if (action >= 0)
|
|
return action;
|
|
protocol = pckt.flow.proto;
|
|
if (protocol == IPPROTO_TCP) {
|
|
if (!parse_tcp(data, data_end, is_ipv6, &pckt))
|
|
return XDP_DROP;
|
|
} else if (protocol == IPPROTO_UDP) {
|
|
if (!parse_udp(data, data_end, is_ipv6, &pckt))
|
|
return XDP_DROP;
|
|
} else {
|
|
return XDP_TX;
|
|
}
|
|
|
|
if (is_ipv6)
|
|
memcpy(vip.vipv6, pckt.flow.dstv6, 16);
|
|
else
|
|
vip.vip = pckt.flow.dst;
|
|
vip.port = pckt.flow.port16[1];
|
|
vip.proto = pckt.flow.proto;
|
|
vip_info = bpf_map_lookup_elem(&vip_map, &vip);
|
|
if (!vip_info) {
|
|
vip.port = 0;
|
|
vip_info = bpf_map_lookup_elem(&vip_map, &vip);
|
|
if (!vip_info)
|
|
return XDP_PASS;
|
|
if (!(vip_info->flags & (1 << 4)))
|
|
pckt.flow.port16[1] = 0;
|
|
}
|
|
if (data_end - data > 1400)
|
|
return XDP_DROP;
|
|
data_stats = bpf_map_lookup_elem(&stats, &stats_key);
|
|
if (!data_stats)
|
|
return XDP_DROP;
|
|
data_stats->v1 += 1;
|
|
if (!dst) {
|
|
if (vip_info->flags & (1 << 0))
|
|
pckt.flow.port16[0] = 0;
|
|
if (!(pckt.flags & (1 << 1)) && !(vip_info->flags & (1 << 1)))
|
|
connection_table_lookup(&dst, &pckt, lru_map);
|
|
if (dst)
|
|
goto out;
|
|
if (pckt.flow.proto == IPPROTO_TCP) {
|
|
struct lb_stats *lru_stats =
|
|
bpf_map_lookup_elem(&stats, &lru_stats_key);
|
|
|
|
if (!lru_stats)
|
|
return XDP_DROP;
|
|
if (pckt.flags & (1 << 1))
|
|
lru_stats->v1 += 1;
|
|
else
|
|
lru_stats->v2 += 1;
|
|
}
|
|
if (!get_packet_dst(&dst, &pckt, vip_info, is_ipv6, lru_map))
|
|
return XDP_DROP;
|
|
data_stats->v2 += 1;
|
|
}
|
|
out:
|
|
cval = bpf_map_lookup_elem(&ctl_array, &mac_addr_pos);
|
|
if (!cval)
|
|
return XDP_DROP;
|
|
if (dst->flags & (1 << 0)) {
|
|
if (!encap_v6(xdp, cval, &pckt, dst, pkt_bytes))
|
|
return XDP_DROP;
|
|
} else {
|
|
if (!encap_v4(xdp, cval, &pckt, dst, pkt_bytes))
|
|
return XDP_DROP;
|
|
}
|
|
vip_num = vip_info->vip_num;
|
|
data_stats = bpf_map_lookup_elem(&stats, &vip_num);
|
|
if (!data_stats)
|
|
return XDP_DROP;
|
|
data_stats->v1 += 1;
|
|
data_stats->v2 += pkt_bytes;
|
|
|
|
data = (void *)(long)xdp->data;
|
|
data_end = (void *)(long)xdp->data_end;
|
|
if (data + 4 > data_end)
|
|
return XDP_DROP;
|
|
*(u32 *)data = dst->dst;
|
|
return XDP_DROP;
|
|
}
|
|
|
|
SEC("xdp")
|
|
int balancer_ingress_v4(struct xdp_md *ctx)
|
|
{
|
|
void *data = (void *)(long)ctx->data;
|
|
void *data_end = (void *)(long)ctx->data_end;
|
|
struct eth_hdr *eth = data;
|
|
__u32 eth_proto;
|
|
__u32 nh_off;
|
|
|
|
nh_off = sizeof(struct eth_hdr);
|
|
if (data + nh_off > data_end)
|
|
return XDP_DROP;
|
|
eth_proto = bpf_ntohs(eth->eth_proto);
|
|
if (eth_proto == ETH_P_IP)
|
|
return process_packet(data, nh_off, data_end, 0, ctx);
|
|
else
|
|
return XDP_DROP;
|
|
}
|
|
|
|
SEC("xdp")
|
|
int balancer_ingress_v6(struct xdp_md *ctx)
|
|
{
|
|
void *data = (void *)(long)ctx->data;
|
|
void *data_end = (void *)(long)ctx->data_end;
|
|
struct eth_hdr *eth = data;
|
|
__u32 eth_proto;
|
|
__u32 nh_off;
|
|
|
|
nh_off = sizeof(struct eth_hdr);
|
|
if (data + nh_off > data_end)
|
|
return XDP_DROP;
|
|
eth_proto = bpf_ntohs(eth->eth_proto);
|
|
if (eth_proto == ETH_P_IPV6)
|
|
return process_packet(data, nh_off, data_end, 1, ctx);
|
|
else
|
|
return XDP_DROP;
|
|
}
|
|
|
|
char _license[] SEC("license") = "GPL";
|