379 lines · c
1/* SPDX-License-Identifier: GPL-2.0 */2/* Copyright (c) 2017-2018 Covalent IO, Inc. http://covalent.io */3#include <stddef.h>4#include <string.h>5#include <linux/bpf.h>6#include <linux/if_ether.h>7#include <linux/if_packet.h>8#include <linux/ip.h>9#include <linux/ipv6.h>10#include <linux/in.h>11#include <linux/udp.h>12#include <linux/tcp.h>13#include <linux/pkt_cls.h>14#include <sys/socket.h>15#include <bpf/bpf_helpers.h>16#include <bpf/bpf_endian.h>17#include "bpf_misc.h"18 19/* Sockmap sample program connects a client and a backend together20 * using cgroups.21 *22 * client:X <---> frontend:80 client:X <---> backend:8023 *24 * For simplicity we hard code values here and bind 1:1. The hard25 * coded values are part of the setup in sockmap.sh script that26 * is associated with this BPF program.27 *28 * The bpf_printk is verbose and prints information as connections29 * are established and verdicts are decided.30 */31 32struct {33 __uint(type, TEST_MAP_TYPE);34 __uint(max_entries, 20);35 __uint(key_size, sizeof(int));36 __uint(value_size, sizeof(int));37} sock_map SEC(".maps");38 39struct {40 __uint(type, TEST_MAP_TYPE);41 __uint(max_entries, 20);42 __uint(key_size, sizeof(int));43 __uint(value_size, sizeof(int));44} sock_map_txmsg SEC(".maps");45 46struct {47 __uint(type, TEST_MAP_TYPE);48 __uint(max_entries, 20);49 __uint(key_size, sizeof(int));50 __uint(value_size, sizeof(int));51} sock_map_redir SEC(".maps");52 53struct {54 __uint(type, BPF_MAP_TYPE_ARRAY);55 __uint(max_entries, 1);56 __type(key, int);57 __type(value, int);58} sock_apply_bytes SEC(".maps");59 60struct {61 __uint(type, BPF_MAP_TYPE_ARRAY);62 __uint(max_entries, 1);63 __type(key, int);64 __type(value, int);65} sock_cork_bytes SEC(".maps");66 67struct {68 __uint(type, BPF_MAP_TYPE_ARRAY);69 __uint(max_entries, 6);70 __type(key, int);71 __type(value, int);72} sock_bytes SEC(".maps");73 74struct {75 __uint(type, BPF_MAP_TYPE_ARRAY);76 __uint(max_entries, 1);77 __type(key, int);78 __type(value, int);79} sock_redir_flags SEC(".maps");80 81struct {82 __uint(type, BPF_MAP_TYPE_ARRAY);83 __uint(max_entries, 3);84 __type(key, int);85 __type(value, int);86} sock_skb_opts SEC(".maps");87 88struct {89 __uint(type, TEST_MAP_TYPE);90 __uint(max_entries, 20);91 __uint(key_size, sizeof(int));92 __uint(value_size, sizeof(int));93} tls_sock_map SEC(".maps");94 95SEC("sk_skb/stream_parser")96int bpf_prog1(struct __sk_buff *skb)97{98 int *f, two = 2;99 100 f = bpf_map_lookup_elem(&sock_skb_opts, &two);101 if (f && *f) {102 return *f;103 }104 return skb->len;105}106 107SEC("sk_skb/stream_verdict")108int bpf_prog2(struct __sk_buff *skb)109{110 __u32 lport = skb->local_port;111 __u32 rport = skb->remote_port;112 int len, *f, ret, zero = 0;113 __u64 flags = 0;114 115 __sink(rport);116 if (lport == 10000)117 ret = 10;118 else119 ret = 1;120 121 len = (__u32)skb->data_end - (__u32)skb->data;122 __sink(len);123 124 f = bpf_map_lookup_elem(&sock_skb_opts, &zero);125 if (f && *f) {126 ret = 3;127 flags = *f;128 }129 130#ifdef SOCKMAP131 return bpf_sk_redirect_map(skb, &sock_map, ret, flags);132#else133 return bpf_sk_redirect_hash(skb, &sock_map, &ret, flags);134#endif135 136}137 138static inline void bpf_write_pass(struct __sk_buff *skb, int offset)139{140 int err = bpf_skb_pull_data(skb, 6 + offset);141 void *data_end;142 char *c;143 144 if (err)145 return;146 147 c = (char *)(long)skb->data;148 data_end = (void *)(long)skb->data_end;149 150 if (c + 5 + offset < data_end)151 memcpy(c + offset, "PASS", 4);152}153 154SEC("sk_skb/stream_verdict")155int bpf_prog3(struct __sk_buff *skb)156{157 int err, *f, ret = SK_PASS;158 const int one = 1;159 160 f = bpf_map_lookup_elem(&sock_skb_opts, &one);161 if (f && *f) {162 __u64 flags = 0;163 164 ret = 0;165 flags = *f;166 167 err = bpf_skb_adjust_room(skb, -13, 0, 0);168 if (err)169 return SK_DROP;170 err = bpf_skb_adjust_room(skb, 4, 0, 0);171 if (err)172 return SK_DROP;173 bpf_write_pass(skb, 0);174#ifdef SOCKMAP175 return bpf_sk_redirect_map(skb, &tls_sock_map, ret, flags);176#else177 return bpf_sk_redirect_hash(skb, &tls_sock_map, &ret, flags);178#endif179 }180 err = bpf_skb_adjust_room(skb, 4, 0, 0);181 if (err)182 return SK_DROP;183 bpf_write_pass(skb, 13);184 return ret;185}186 187SEC("sockops")188int bpf_sockmap(struct bpf_sock_ops *skops)189{190 __u32 lport, rport;191 int op, ret;192 193 op = (int) skops->op;194 195 switch (op) {196 case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB:197 lport = skops->local_port;198 rport = skops->remote_port;199 200 if (lport == 10000) {201 ret = 1;202#ifdef SOCKMAP203 bpf_sock_map_update(skops, &sock_map, &ret,204 BPF_NOEXIST);205#else206 bpf_sock_hash_update(skops, &sock_map, &ret,207 BPF_NOEXIST);208#endif209 }210 break;211 case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB:212 lport = skops->local_port;213 rport = skops->remote_port;214 215 if (bpf_ntohl(rport) == 10001) {216 ret = 10;217#ifdef SOCKMAP218 bpf_sock_map_update(skops, &sock_map, &ret,219 BPF_NOEXIST);220#else221 bpf_sock_hash_update(skops, &sock_map, &ret,222 BPF_NOEXIST);223#endif224 }225 break;226 default:227 break;228 }229 230 return 0;231}232 233SEC("sk_msg")234int bpf_prog4(struct sk_msg_md *msg)235{236 int *bytes, zero = 0, one = 1, two = 2, three = 3, four = 4, five = 5;237 int *start, *end, *start_push, *end_push, *start_pop, *pop, err = 0;238 239 bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);240 if (bytes)241 bpf_msg_apply_bytes(msg, *bytes);242 bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);243 if (bytes)244 bpf_msg_cork_bytes(msg, *bytes);245 start = bpf_map_lookup_elem(&sock_bytes, &zero);246 end = bpf_map_lookup_elem(&sock_bytes, &one);247 if (start && end)248 bpf_msg_pull_data(msg, *start, *end, 0);249 start_push = bpf_map_lookup_elem(&sock_bytes, &two);250 end_push = bpf_map_lookup_elem(&sock_bytes, &three);251 if (start_push && end_push) {252 err = bpf_msg_push_data(msg, *start_push, *end_push, 0);253 if (err)254 return SK_DROP;255 }256 start_pop = bpf_map_lookup_elem(&sock_bytes, &four);257 pop = bpf_map_lookup_elem(&sock_bytes, &five);258 if (start_pop && pop)259 bpf_msg_pop_data(msg, *start_pop, *pop, 0);260 return SK_PASS;261}262 263SEC("sk_msg")264int bpf_prog6(struct sk_msg_md *msg)265{266 int zero = 0, one = 1, two = 2, three = 3, four = 4, five = 5, key = 0;267 int *bytes, *start, *end, *start_push, *end_push, *start_pop, *pop, *f;268 int err = 0;269 __u64 flags = 0;270 271 bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);272 if (bytes)273 bpf_msg_apply_bytes(msg, *bytes);274 bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);275 if (bytes)276 bpf_msg_cork_bytes(msg, *bytes);277 278 start = bpf_map_lookup_elem(&sock_bytes, &zero);279 end = bpf_map_lookup_elem(&sock_bytes, &one);280 if (start && end)281 bpf_msg_pull_data(msg, *start, *end, 0);282 283 start_push = bpf_map_lookup_elem(&sock_bytes, &two);284 end_push = bpf_map_lookup_elem(&sock_bytes, &three);285 if (start_push && end_push) {286 err = bpf_msg_push_data(msg, *start_push, *end_push, 0);287 if (err)288 return SK_DROP;289 }290 291 start_pop = bpf_map_lookup_elem(&sock_bytes, &four);292 pop = bpf_map_lookup_elem(&sock_bytes, &five);293 if (start_pop && pop)294 bpf_msg_pop_data(msg, *start_pop, *pop, 0);295 296 f = bpf_map_lookup_elem(&sock_redir_flags, &zero);297 if (f && *f) {298 key = 2;299 flags = *f;300 }301#ifdef SOCKMAP302 return bpf_msg_redirect_map(msg, &sock_map_redir, key, flags);303#else304 return bpf_msg_redirect_hash(msg, &sock_map_redir, &key, flags);305#endif306}307 308SEC("sk_msg")309int bpf_prog8(struct sk_msg_md *msg)310{311 void *data_end = (void *)(long) msg->data_end;312 void *data = (void *)(long) msg->data;313 int ret = 0, *bytes, zero = 0;314 315 bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);316 if (bytes) {317 ret = bpf_msg_apply_bytes(msg, *bytes);318 if (ret)319 return SK_DROP;320 } else {321 return SK_DROP;322 }323 324 __sink(data_end);325 __sink(data);326 327 return SK_PASS;328}329 330SEC("sk_msg")331int bpf_prog9(struct sk_msg_md *msg)332{333 void *data_end = (void *)(long) msg->data_end;334 void *data = (void *)(long) msg->data;335 int ret = 0, *bytes, zero = 0;336 337 bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);338 if (bytes) {339 if (((__u64)data_end - (__u64)data) >= *bytes)340 return SK_PASS;341 ret = bpf_msg_cork_bytes(msg, *bytes);342 if (ret)343 return SK_DROP;344 }345 return SK_PASS;346}347 348SEC("sk_msg")349int bpf_prog10(struct sk_msg_md *msg)350{351 int *bytes, *start, *end, *start_push, *end_push, *start_pop, *pop;352 int zero = 0, one = 1, two = 2, three = 3, four = 4, five = 5, err = 0;353 354 bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);355 if (bytes)356 bpf_msg_apply_bytes(msg, *bytes);357 bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);358 if (bytes)359 bpf_msg_cork_bytes(msg, *bytes);360 start = bpf_map_lookup_elem(&sock_bytes, &zero);361 end = bpf_map_lookup_elem(&sock_bytes, &one);362 if (start && end)363 bpf_msg_pull_data(msg, *start, *end, 0);364 start_push = bpf_map_lookup_elem(&sock_bytes, &two);365 end_push = bpf_map_lookup_elem(&sock_bytes, &three);366 if (start_push && end_push) {367 err = bpf_msg_push_data(msg, *start_push, *end_push, 0);368 if (err)369 return SK_PASS;370 }371 start_pop = bpf_map_lookup_elem(&sock_bytes, &four);372 pop = bpf_map_lookup_elem(&sock_bytes, &five);373 if (start_pop && pop)374 bpf_msg_pop_data(msg, *start_pop, *pop, 0);375 return SK_DROP;376}377 378char _license[] SEC("license") = "GPL";379