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1// SPDX-License-Identifier: GPL-2.02// Copyright (c) 2017 Facebook3#include <stddef.h>4#include <stdbool.h>5#include <string.h>6#include <linux/pkt_cls.h>7#include <linux/bpf.h>8#include <linux/in.h>9#include <linux/if_ether.h>10#include <linux/ip.h>11#include <linux/ipv6.h>12#include <linux/icmp.h>13#include <linux/icmpv6.h>14#include <linux/tcp.h>15#include <linux/udp.h>16#include <bpf/bpf_helpers.h>17#include <bpf/bpf_endian.h>18#include "bpf_compiler.h"19 20static __always_inline __u32 rol32(__u32 word, unsigned int shift)21{22 return (word << shift) | (word >> ((-shift) & 31));23}24 25/* copy paste of jhash from kernel sources to make sure llvm26 * can compile it into valid sequence of bpf instructions27 */28#define __jhash_mix(a, b, c) \29{ \30 a -= c; a ^= rol32(c, 4); c += b; \31 b -= a; b ^= rol32(a, 6); a += c; \32 c -= b; c ^= rol32(b, 8); b += a; \33 a -= c; a ^= rol32(c, 16); c += b; \34 b -= a; b ^= rol32(a, 19); a += c; \35 c -= b; c ^= rol32(b, 4); b += a; \36}37 38#define __jhash_final(a, b, c) \39{ \40 c ^= b; c -= rol32(b, 14); \41 a ^= c; a -= rol32(c, 11); \42 b ^= a; b -= rol32(a, 25); \43 c ^= b; c -= rol32(b, 16); \44 a ^= c; a -= rol32(c, 4); \45 b ^= a; b -= rol32(a, 14); \46 c ^= b; c -= rol32(b, 24); \47}48 49#define JHASH_INITVAL 0xdeadbeef50 51typedef unsigned int u32;52 53static __noinline54u32 jhash(const void *key, u32 length, u32 initval)55{56 u32 a, b, c;57 const unsigned char *k = key;58 59 a = b = c = JHASH_INITVAL + length + initval;60 61 while (length > 12) {62 a += *(u32 *)(k);63 b += *(u32 *)(k + 4);64 c += *(u32 *)(k + 8);65 __jhash_mix(a, b, c);66 length -= 12;67 k += 12;68 }69 switch (length) {70 case 12: c += (u32)k[11]<<24;71 case 11: c += (u32)k[10]<<16;72 case 10: c += (u32)k[9]<<8;73 case 9: c += k[8];74 case 8: b += (u32)k[7]<<24;75 case 7: b += (u32)k[6]<<16;76 case 6: b += (u32)k[5]<<8;77 case 5: b += k[4];78 case 4: a += (u32)k[3]<<24;79 case 3: a += (u32)k[2]<<16;80 case 2: a += (u32)k[1]<<8;81 case 1: a += k[0];82 __jhash_final(a, b, c);83 case 0: /* Nothing left to add */84 break;85 }86 87 return c;88}89 90__noinline91u32 __jhash_nwords(u32 a, u32 b, u32 c, u32 initval)92{93 a += initval;94 b += initval;95 c += initval;96 __jhash_final(a, b, c);97 return c;98}99 100__noinline101u32 jhash_2words(u32 a, u32 b, u32 initval)102{103 return __jhash_nwords(a, b, 0, initval + JHASH_INITVAL + (2 << 2));104}105 106struct flow_key {107 union {108 __be32 src;109 __be32 srcv6[4];110 };111 union {112 __be32 dst;113 __be32 dstv6[4];114 };115 union {116 __u32 ports;117 __u16 port16[2];118 };119 __u8 proto;120};121 122struct packet_description {123 struct flow_key flow;124 __u8 flags;125};126 127struct ctl_value {128 union {129 __u64 value;130 __u32 ifindex;131 __u8 mac[6];132 };133};134 135struct vip_definition {136 union {137 __be32 vip;138 __be32 vipv6[4];139 };140 __u16 port;141 __u16 family;142 __u8 proto;143};144 145struct vip_meta {146 __u32 flags;147 __u32 vip_num;148};149 150struct real_pos_lru {151 __u32 pos;152 __u64 atime;153};154 155struct real_definition {156 union {157 __be32 dst;158 __be32 dstv6[4];159 };160 __u8 flags;161};162 163struct lb_stats {164 __u64 v2;165 __u64 v1;166};167 168struct {169 __uint(type, BPF_MAP_TYPE_HASH);170 __uint(max_entries, 512);171 __type(key, struct vip_definition);172 __type(value, struct vip_meta);173} vip_map SEC(".maps");174 175struct {176 __uint(type, BPF_MAP_TYPE_LRU_HASH);177 __uint(max_entries, 300);178 __uint(map_flags, 1U << 1);179 __type(key, struct flow_key);180 __type(value, struct real_pos_lru);181} lru_cache SEC(".maps");182 183struct {184 __uint(type, BPF_MAP_TYPE_ARRAY);185 __uint(max_entries, 12 * 655);186 __type(key, __u32);187 __type(value, __u32);188} ch_rings SEC(".maps");189 190struct {191 __uint(type, BPF_MAP_TYPE_ARRAY);192 __uint(max_entries, 40);193 __type(key, __u32);194 __type(value, struct real_definition);195} reals SEC(".maps");196 197struct {198 __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);199 __uint(max_entries, 515);200 __type(key, __u32);201 __type(value, struct lb_stats);202} stats SEC(".maps");203 204struct {205 __uint(type, BPF_MAP_TYPE_ARRAY);206 __uint(max_entries, 16);207 __type(key, __u32);208 __type(value, struct ctl_value);209} ctl_array SEC(".maps");210 211struct eth_hdr {212 unsigned char eth_dest[6];213 unsigned char eth_source[6];214 unsigned short eth_proto;215};216 217static __noinline __u64 calc_offset(bool is_ipv6, bool is_icmp)218{219 __u64 off = sizeof(struct eth_hdr);220 if (is_ipv6) {221 off += sizeof(struct ipv6hdr);222 if (is_icmp)223 off += sizeof(struct icmp6hdr) + sizeof(struct ipv6hdr);224 } else {225 off += sizeof(struct iphdr);226 if (is_icmp)227 off += sizeof(struct icmphdr) + sizeof(struct iphdr);228 }229 return off;230}231 232static __attribute__ ((noinline))233bool parse_udp(void *data, void *data_end,234 bool is_ipv6, struct packet_description *pckt)235{236 237 bool is_icmp = !((pckt->flags & (1 << 0)) == 0);238 __u64 off = calc_offset(is_ipv6, is_icmp);239 struct udphdr *udp;240 udp = data + off;241 242 if (udp + 1 > data_end)243 return false;244 if (!is_icmp) {245 pckt->flow.port16[0] = udp->source;246 pckt->flow.port16[1] = udp->dest;247 } else {248 pckt->flow.port16[0] = udp->dest;249 pckt->flow.port16[1] = udp->source;250 }251 return true;252}253 254static __attribute__ ((noinline))255bool parse_tcp(void *data, void *data_end,256 bool is_ipv6, struct packet_description *pckt)257{258 259 bool is_icmp = !((pckt->flags & (1 << 0)) == 0);260 __u64 off = calc_offset(is_ipv6, is_icmp);261 struct tcphdr *tcp;262 263 tcp = data + off;264 if (tcp + 1 > data_end)265 return false;266 if (tcp->syn)267 pckt->flags |= (1 << 1);268 if (!is_icmp) {269 pckt->flow.port16[0] = tcp->source;270 pckt->flow.port16[1] = tcp->dest;271 } else {272 pckt->flow.port16[0] = tcp->dest;273 pckt->flow.port16[1] = tcp->source;274 }275 return true;276}277 278static __attribute__ ((noinline))279bool encap_v6(struct xdp_md *xdp, struct ctl_value *cval,280 struct packet_description *pckt,281 struct real_definition *dst, __u32 pkt_bytes)282{283 struct eth_hdr *new_eth;284 struct eth_hdr *old_eth;285 struct ipv6hdr *ip6h;286 __u32 ip_suffix;287 void *data_end;288 void *data;289 290 if (bpf_xdp_adjust_head(xdp, 0 - (int)sizeof(struct ipv6hdr)))291 return false;292 data = (void *)(long)xdp->data;293 data_end = (void *)(long)xdp->data_end;294 new_eth = data;295 ip6h = data + sizeof(struct eth_hdr);296 old_eth = data + sizeof(struct ipv6hdr);297 if (new_eth + 1 > data_end ||298 old_eth + 1 > data_end || ip6h + 1 > data_end)299 return false;300 memcpy(new_eth->eth_dest, cval->mac, 6);301 memcpy(new_eth->eth_source, old_eth->eth_dest, 6);302 new_eth->eth_proto = 56710;303 ip6h->version = 6;304 ip6h->priority = 0;305 memset(ip6h->flow_lbl, 0, sizeof(ip6h->flow_lbl));306 307 ip6h->nexthdr = IPPROTO_IPV6;308 ip_suffix = pckt->flow.srcv6[3] ^ pckt->flow.port16[0];309 ip6h->payload_len =310 bpf_htons(pkt_bytes + sizeof(struct ipv6hdr));311 ip6h->hop_limit = 4;312 313 ip6h->saddr.in6_u.u6_addr32[0] = 1;314 ip6h->saddr.in6_u.u6_addr32[1] = 2;315 ip6h->saddr.in6_u.u6_addr32[2] = 3;316 ip6h->saddr.in6_u.u6_addr32[3] = ip_suffix;317 memcpy(ip6h->daddr.in6_u.u6_addr32, dst->dstv6, 16);318 return true;319}320 321#ifndef __clang__322#pragma GCC push_options323/* GCC optimization collapses functions and increases the number of arguments324 * beyond the compatible amount supported by BPF.325 */326#pragma GCC optimize("-fno-ipa-sra")327#endif328 329static __attribute__ ((noinline))330bool encap_v4(struct xdp_md *xdp, struct ctl_value *cval,331 struct packet_description *pckt,332 struct real_definition *dst, __u32 pkt_bytes)333{334 335 __u32 ip_suffix = bpf_ntohs(pckt->flow.port16[0]);336 struct eth_hdr *new_eth;337 struct eth_hdr *old_eth;338 __u16 *next_iph_u16;339 struct iphdr *iph;340 __u32 csum = 0;341 void *data_end;342 void *data;343 344 ip_suffix <<= 15;345 ip_suffix ^= pckt->flow.src;346 if (bpf_xdp_adjust_head(xdp, 0 - (int)sizeof(struct iphdr)))347 return false;348 data = (void *)(long)xdp->data;349 data_end = (void *)(long)xdp->data_end;350 new_eth = data;351 iph = data + sizeof(struct eth_hdr);352 old_eth = data + sizeof(struct iphdr);353 if (new_eth + 1 > data_end ||354 old_eth + 1 > data_end || iph + 1 > data_end)355 return false;356 memcpy(new_eth->eth_dest, cval->mac, 6);357 memcpy(new_eth->eth_source, old_eth->eth_dest, 6);358 new_eth->eth_proto = 8;359 iph->version = 4;360 iph->ihl = 5;361 iph->frag_off = 0;362 iph->protocol = IPPROTO_IPIP;363 iph->check = 0;364 iph->tos = 1;365 iph->tot_len = bpf_htons(pkt_bytes + sizeof(struct iphdr));366 /* don't update iph->daddr, since it will overwrite old eth_proto367 * and multiple iterations of bpf_prog_run() will fail368 */369 370 iph->saddr = ((0xFFFF0000 & ip_suffix) | 4268) ^ dst->dst;371 iph->ttl = 4;372 373 next_iph_u16 = (__u16 *) iph;374 __pragma_loop_unroll_full375 for (int i = 0; i < sizeof(struct iphdr) >> 1; i++)376 csum += *next_iph_u16++;377 iph->check = ~((csum & 0xffff) + (csum >> 16));378 if (bpf_xdp_adjust_head(xdp, (int)sizeof(struct iphdr)))379 return false;380 return true;381}382 383#ifndef __clang__384#pragma GCC pop_options385#endif386 387static __attribute__ ((noinline))388int swap_mac_and_send(void *data, void *data_end)389{390 unsigned char tmp_mac[6];391 struct eth_hdr *eth;392 393 eth = data;394 memcpy(tmp_mac, eth->eth_source, 6);395 memcpy(eth->eth_source, eth->eth_dest, 6);396 memcpy(eth->eth_dest, tmp_mac, 6);397 return XDP_TX;398}399 400static __attribute__ ((noinline))401int send_icmp_reply(void *data, void *data_end)402{403 struct icmphdr *icmp_hdr;404 __u16 *next_iph_u16;405 __u32 tmp_addr = 0;406 struct iphdr *iph;407 __u32 csum = 0;408 __u64 off = 0;409 410 if (data + sizeof(struct eth_hdr)411 + sizeof(struct iphdr) + sizeof(struct icmphdr) > data_end)412 return XDP_DROP;413 off += sizeof(struct eth_hdr);414 iph = data + off;415 off += sizeof(struct iphdr);416 icmp_hdr = data + off;417 icmp_hdr->type = 0;418 icmp_hdr->checksum += 0x0007;419 iph->ttl = 4;420 tmp_addr = iph->daddr;421 iph->daddr = iph->saddr;422 iph->saddr = tmp_addr;423 iph->check = 0;424 next_iph_u16 = (__u16 *) iph;425 __pragma_loop_unroll_full426 for (int i = 0; i < sizeof(struct iphdr) >> 1; i++)427 csum += *next_iph_u16++;428 iph->check = ~((csum & 0xffff) + (csum >> 16));429 return swap_mac_and_send(data, data_end);430}431 432static __attribute__ ((noinline))433int send_icmp6_reply(void *data, void *data_end)434{435 struct icmp6hdr *icmp_hdr;436 struct ipv6hdr *ip6h;437 __be32 tmp_addr[4];438 __u64 off = 0;439 440 if (data + sizeof(struct eth_hdr)441 + sizeof(struct ipv6hdr) + sizeof(struct icmp6hdr) > data_end)442 return XDP_DROP;443 off += sizeof(struct eth_hdr);444 ip6h = data + off;445 off += sizeof(struct ipv6hdr);446 icmp_hdr = data + off;447 icmp_hdr->icmp6_type = 129;448 icmp_hdr->icmp6_cksum -= 0x0001;449 ip6h->hop_limit = 4;450 memcpy(tmp_addr, ip6h->saddr.in6_u.u6_addr32, 16);451 memcpy(ip6h->saddr.in6_u.u6_addr32, ip6h->daddr.in6_u.u6_addr32, 16);452 memcpy(ip6h->daddr.in6_u.u6_addr32, tmp_addr, 16);453 return swap_mac_and_send(data, data_end);454}455 456static __attribute__ ((noinline))457int parse_icmpv6(void *data, void *data_end, __u64 off,458 struct packet_description *pckt)459{460 struct icmp6hdr *icmp_hdr;461 struct ipv6hdr *ip6h;462 463 icmp_hdr = data + off;464 if (icmp_hdr + 1 > data_end)465 return XDP_DROP;466 if (icmp_hdr->icmp6_type == 128)467 return send_icmp6_reply(data, data_end);468 if (icmp_hdr->icmp6_type != 3)469 return XDP_PASS;470 off += sizeof(struct icmp6hdr);471 ip6h = data + off;472 if (ip6h + 1 > data_end)473 return XDP_DROP;474 pckt->flow.proto = ip6h->nexthdr;475 pckt->flags |= (1 << 0);476 memcpy(pckt->flow.srcv6, ip6h->daddr.in6_u.u6_addr32, 16);477 memcpy(pckt->flow.dstv6, ip6h->saddr.in6_u.u6_addr32, 16);478 return -1;479}480 481static __attribute__ ((noinline))482int parse_icmp(void *data, void *data_end, __u64 off,483 struct packet_description *pckt)484{485 struct icmphdr *icmp_hdr;486 struct iphdr *iph;487 488 icmp_hdr = data + off;489 if (icmp_hdr + 1 > data_end)490 return XDP_DROP;491 if (icmp_hdr->type == 8)492 return send_icmp_reply(data, data_end);493 if ((icmp_hdr->type != 3) || (icmp_hdr->code != 4))494 return XDP_PASS;495 off += sizeof(struct icmphdr);496 iph = data + off;497 if (iph + 1 > data_end)498 return XDP_DROP;499 if (iph->ihl != 5)500 return XDP_DROP;501 pckt->flow.proto = iph->protocol;502 pckt->flags |= (1 << 0);503 pckt->flow.src = iph->daddr;504 pckt->flow.dst = iph->saddr;505 return -1;506}507 508static __attribute__ ((noinline))509__u32 get_packet_hash(struct packet_description *pckt,510 bool hash_16bytes)511{512 if (hash_16bytes)513 return jhash_2words(jhash(pckt->flow.srcv6, 16, 12),514 pckt->flow.ports, 24);515 else516 return jhash_2words(pckt->flow.src, pckt->flow.ports,517 24);518}519 520__attribute__ ((noinline))521static bool get_packet_dst(struct real_definition **real,522 struct packet_description *pckt,523 struct vip_meta *vip_info,524 bool is_ipv6, void *lru_map)525{526 struct real_pos_lru new_dst_lru = { };527 bool hash_16bytes = is_ipv6;528 __u32 *real_pos, hash, key;529 __u64 cur_time;530 531 if (vip_info->flags & (1 << 2))532 hash_16bytes = 1;533 if (vip_info->flags & (1 << 3)) {534 pckt->flow.port16[0] = pckt->flow.port16[1];535 memset(pckt->flow.srcv6, 0, 16);536 }537 hash = get_packet_hash(pckt, hash_16bytes);538 if (hash != 0x358459b7 /* jhash of ipv4 packet */ &&539 hash != 0x2f4bc6bb /* jhash of ipv6 packet */)540 return false;541 key = 2 * vip_info->vip_num + hash % 2;542 real_pos = bpf_map_lookup_elem(&ch_rings, &key);543 if (!real_pos)544 return false;545 key = *real_pos;546 *real = bpf_map_lookup_elem(&reals, &key);547 if (!(*real))548 return false;549 if (!(vip_info->flags & (1 << 1))) {550 __u32 conn_rate_key = 512 + 2;551 struct lb_stats *conn_rate_stats =552 bpf_map_lookup_elem(&stats, &conn_rate_key);553 554 if (!conn_rate_stats)555 return true;556 cur_time = bpf_ktime_get_ns();557 if ((cur_time - conn_rate_stats->v2) >> 32 > 0xffFFFF) {558 conn_rate_stats->v1 = 1;559 conn_rate_stats->v2 = cur_time;560 } else {561 conn_rate_stats->v1 += 1;562 if (conn_rate_stats->v1 >= 1)563 return true;564 }565 if (pckt->flow.proto == IPPROTO_UDP)566 new_dst_lru.atime = cur_time;567 new_dst_lru.pos = key;568 bpf_map_update_elem(lru_map, &pckt->flow, &new_dst_lru, 0);569 }570 return true;571}572 573__attribute__ ((noinline))574static void connection_table_lookup(struct real_definition **real,575 struct packet_description *pckt,576 void *lru_map)577{578 579 struct real_pos_lru *dst_lru;580 __u64 cur_time;581 __u32 key;582 583 dst_lru = bpf_map_lookup_elem(lru_map, &pckt->flow);584 if (!dst_lru)585 return;586 if (pckt->flow.proto == IPPROTO_UDP) {587 cur_time = bpf_ktime_get_ns();588 if (cur_time - dst_lru->atime > 300000)589 return;590 dst_lru->atime = cur_time;591 }592 key = dst_lru->pos;593 *real = bpf_map_lookup_elem(&reals, &key);594}595 596/* don't believe your eyes!597 * below function has 6 arguments whereas bpf and llvm allow maximum of 5598 * but since it's _static_ llvm can optimize one argument away599 */600__attribute__ ((noinline))601static int process_l3_headers_v6(struct packet_description *pckt,602 __u8 *protocol, __u64 off,603 __u16 *pkt_bytes, void *extra_args[2])604{605 struct ipv6hdr *ip6h;606 __u64 iph_len;607 int action;608 void *data = extra_args[0];609 void *data_end = extra_args[1];610 611 ip6h = data + off;612 if (ip6h + 1 > data_end)613 return XDP_DROP;614 iph_len = sizeof(struct ipv6hdr);615 *protocol = ip6h->nexthdr;616 pckt->flow.proto = *protocol;617 *pkt_bytes = bpf_ntohs(ip6h->payload_len);618 off += iph_len;619 if (*protocol == 45) {620 return XDP_DROP;621 } else if (*protocol == 59) {622 action = parse_icmpv6(data, data_end, off, pckt);623 if (action >= 0)624 return action;625 } else {626 memcpy(pckt->flow.srcv6, ip6h->saddr.in6_u.u6_addr32, 16);627 memcpy(pckt->flow.dstv6, ip6h->daddr.in6_u.u6_addr32, 16);628 }629 return -1;630}631 632__attribute__ ((noinline))633static int process_l3_headers_v4(struct packet_description *pckt,634 __u8 *protocol, __u64 off,635 __u16 *pkt_bytes, void *extra_args[2])636{637 struct iphdr *iph;638 int action;639 void *data = extra_args[0];640 void *data_end = extra_args[1];641 642 iph = data + off;643 if (iph + 1 > data_end)644 return XDP_DROP;645 if (iph->ihl != 5)646 return XDP_DROP;647 *protocol = iph->protocol;648 pckt->flow.proto = *protocol;649 *pkt_bytes = bpf_ntohs(iph->tot_len);650 off += 20;651 if (iph->frag_off & 65343)652 return XDP_DROP;653 if (*protocol == IPPROTO_ICMP) {654 action = parse_icmp(data, data_end, off, pckt);655 if (action >= 0)656 return action;657 } else {658 pckt->flow.src = iph->saddr;659 pckt->flow.dst = iph->daddr;660 }661 return -1;662}663 664__attribute__ ((noinline))665static int process_packet(void *data, __u64 off, void *data_end,666 bool is_ipv6, struct xdp_md *xdp)667{668 669 struct real_definition *dst = NULL;670 struct packet_description pckt = { };671 struct vip_definition vip = { };672 struct lb_stats *data_stats;673 void *lru_map = &lru_cache;674 struct vip_meta *vip_info;675 __u32 lru_stats_key = 513;676 __u32 mac_addr_pos = 0;677 __u32 stats_key = 512;678 struct ctl_value *cval;679 __u16 pkt_bytes;680 __u8 protocol;681 __u32 vip_num;682 int action;683 void *extra_args[2] = { data, data_end };684 685 if (is_ipv6)686 action = process_l3_headers_v6(&pckt, &protocol, off,687 &pkt_bytes, extra_args);688 else689 action = process_l3_headers_v4(&pckt, &protocol, off,690 &pkt_bytes, extra_args);691 if (action >= 0)692 return action;693 protocol = pckt.flow.proto;694 if (protocol == IPPROTO_TCP) {695 if (!parse_tcp(data, data_end, is_ipv6, &pckt))696 return XDP_DROP;697 } else if (protocol == IPPROTO_UDP) {698 if (!parse_udp(data, data_end, is_ipv6, &pckt))699 return XDP_DROP;700 } else {701 return XDP_TX;702 }703 704 if (is_ipv6)705 memcpy(vip.vipv6, pckt.flow.dstv6, 16);706 else707 vip.vip = pckt.flow.dst;708 vip.port = pckt.flow.port16[1];709 vip.proto = pckt.flow.proto;710 vip_info = bpf_map_lookup_elem(&vip_map, &vip);711 if (!vip_info) {712 vip.port = 0;713 vip_info = bpf_map_lookup_elem(&vip_map, &vip);714 if (!vip_info)715 return XDP_PASS;716 if (!(vip_info->flags & (1 << 4)))717 pckt.flow.port16[1] = 0;718 }719 if (data_end - data > 1400)720 return XDP_DROP;721 data_stats = bpf_map_lookup_elem(&stats, &stats_key);722 if (!data_stats)723 return XDP_DROP;724 data_stats->v1 += 1;725 if (!dst) {726 if (vip_info->flags & (1 << 0))727 pckt.flow.port16[0] = 0;728 if (!(pckt.flags & (1 << 1)) && !(vip_info->flags & (1 << 1)))729 connection_table_lookup(&dst, &pckt, lru_map);730 if (dst)731 goto out;732 if (pckt.flow.proto == IPPROTO_TCP) {733 struct lb_stats *lru_stats =734 bpf_map_lookup_elem(&stats, &lru_stats_key);735 736 if (!lru_stats)737 return XDP_DROP;738 if (pckt.flags & (1 << 1))739 lru_stats->v1 += 1;740 else741 lru_stats->v2 += 1;742 }743 if (!get_packet_dst(&dst, &pckt, vip_info, is_ipv6, lru_map))744 return XDP_DROP;745 data_stats->v2 += 1;746 }747out:748 cval = bpf_map_lookup_elem(&ctl_array, &mac_addr_pos);749 if (!cval)750 return XDP_DROP;751 if (dst->flags & (1 << 0)) {752 if (!encap_v6(xdp, cval, &pckt, dst, pkt_bytes))753 return XDP_DROP;754 } else {755 if (!encap_v4(xdp, cval, &pckt, dst, pkt_bytes))756 return XDP_DROP;757 }758 vip_num = vip_info->vip_num;759 data_stats = bpf_map_lookup_elem(&stats, &vip_num);760 if (!data_stats)761 return XDP_DROP;762 data_stats->v1 += 1;763 data_stats->v2 += pkt_bytes;764 765 data = (void *)(long)xdp->data;766 data_end = (void *)(long)xdp->data_end;767 if (data + 4 > data_end)768 return XDP_DROP;769 *(u32 *)data = dst->dst;770 return XDP_DROP;771}772 773SEC("xdp")774int balancer_ingress_v4(struct xdp_md *ctx)775{776 void *data = (void *)(long)ctx->data;777 void *data_end = (void *)(long)ctx->data_end;778 struct eth_hdr *eth = data;779 __u32 eth_proto;780 __u32 nh_off;781 782 nh_off = sizeof(struct eth_hdr);783 if (data + nh_off > data_end)784 return XDP_DROP;785 eth_proto = bpf_ntohs(eth->eth_proto);786 if (eth_proto == ETH_P_IP)787 return process_packet(data, nh_off, data_end, 0, ctx);788 else789 return XDP_DROP;790}791 792SEC("xdp")793int balancer_ingress_v6(struct xdp_md *ctx)794{795 void *data = (void *)(long)ctx->data;796 void *data_end = (void *)(long)ctx->data_end;797 struct eth_hdr *eth = data;798 __u32 eth_proto;799 __u32 nh_off;800 801 nh_off = sizeof(struct eth_hdr);802 if (data + nh_off > data_end)803 return XDP_DROP;804 eth_proto = bpf_ntohs(eth->eth_proto);805 if (eth_proto == ETH_P_IPV6)806 return process_packet(data, nh_off, data_end, 1, ctx);807 else808 return XDP_DROP;809}810 811char _license[] SEC("license") = "GPL";812