samples/bpf/tcbpf2_kern.c

   1 /* Copyright (c) 2016 VMware
   2  * Copyright (c) 2016 Facebook
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of version 2 of the GNU General Public
   6  * License as published by the Free Software Foundation.
   7  */
   8 #define KBUILD_MODNAME "foo"
   9 #include <uapi/linux/bpf.h>
  10 #include <uapi/linux/if_ether.h>
  11 #include <uapi/linux/if_packet.h>
  12 #include <uapi/linux/ip.h>
  13 #include <uapi/linux/ipv6.h>
  14 #include <uapi/linux/in.h>
  15 #include <uapi/linux/tcp.h>
  16 #include <uapi/linux/filter.h>
  17 #include <uapi/linux/pkt_cls.h>
  18 #include <net/ipv6.h>
  19 #include "bpf_helpers.h"
  20
  21 #define _htonl __builtin_bswap32
  22 #define ERROR(ret) do {\
  23                 char fmt[] = "ERROR line:%d ret:%d\n";\
  24                 bpf_trace_printk(fmt, sizeof(fmt), __LINE__, ret); \
  25         } while(0)
  26
  27 struct geneve_opt {
  28         __be16  opt_class;
  29         u8      type;
  30         u8      length:5;
  31         u8      r3:1;
  32         u8      r2:1;
  33         u8      r1:1;
  34         u8      opt_data[8]; /* hard-coded to 8 byte */
  35 };
  36
  37 struct vxlan_metadata {
  38         u32     gbp;
  39 };
  40
  41 SEC("gre_set_tunnel")
  42 int _gre_set_tunnel(struct __sk_buff *skb)
  43 {
  44         int ret;
  45         struct bpf_tunnel_key key;
  46
  47         __builtin_memset(&key, 0x0, sizeof(key));
  48         key.remote_ipv4 = 0xac100164; /* 172.16.1.100 */
  49         key.tunnel_id = 2;
  50         key.tunnel_tos = 0;
  51         key.tunnel_ttl = 64;
  52
  53         ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key), BPF_F_ZERO_CSUM_TX);
  54         if (ret < 0) {
  55                 ERROR(ret);
  56                 return TC_ACT_SHOT;
  57         }
  58
  59         return TC_ACT_OK;
  60 }
  61
  62 SEC("gre_get_tunnel")
  63 int _gre_get_tunnel(struct __sk_buff *skb)
  64 {
  65         int ret;
  66         struct bpf_tunnel_key key;
  67         char fmt[] = "key %d remote ip 0x%x\n";
  68
  69         ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0);
  70         if (ret < 0) {
  71                 ERROR(ret);
  72                 return TC_ACT_SHOT;
  73         }
  74
  75         bpf_trace_printk(fmt, sizeof(fmt), key.tunnel_id, key.remote_ipv4);
  76         return TC_ACT_OK;
  77 }
  78
  79 SEC("vxlan_set_tunnel")
  80 int _vxlan_set_tunnel(struct __sk_buff *skb)
  81 {
  82         int ret;
  83         struct bpf_tunnel_key key;
  84         struct vxlan_metadata md;
  85
  86         __builtin_memset(&key, 0x0, sizeof(key));
  87         key.remote_ipv4 = 0xac100164; /* 172.16.1.100 */
  88         key.tunnel_id = 2;
  89         key.tunnel_tos = 0;
  90         key.tunnel_ttl = 64;
  91
  92         ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key), BPF_F_ZERO_CSUM_TX);
  93         if (ret < 0) {
  94                 ERROR(ret);
  95                 return TC_ACT_SHOT;
  96         }
  97
  98         md.gbp = 0x800FF; /* Set VXLAN Group Policy extension */
  99         ret = bpf_skb_set_tunnel_opt(skb, &md, sizeof(md));
 100         if (ret < 0) {
 101                 ERROR(ret);
 102                 return TC_ACT_SHOT;
 103         }
 104
 105         return TC_ACT_OK;
 106 }
 107
 108 SEC("vxlan_get_tunnel")
 109 int _vxlan_get_tunnel(struct __sk_buff *skb)
 110 {
 111         int ret;
 112         struct bpf_tunnel_key key;
 113         struct vxlan_metadata md;
 114         char fmt[] = "key %d remote ip 0x%x vxlan gbp 0x%x\n";
 115
 116         ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0);
 117         if (ret < 0) {
 118                 ERROR(ret);
 119                 return TC_ACT_SHOT;
 120         }
 121
 122         ret = bpf_skb_get_tunnel_opt(skb, &md, sizeof(md));
 123         if (ret < 0) {
 124                 ERROR(ret);
 125                 return TC_ACT_SHOT;
 126         }
 127
 128         bpf_trace_printk(fmt, sizeof(fmt),
 129                         key.tunnel_id, key.remote_ipv4, md.gbp);
 130
 131         return TC_ACT_OK;
 132 }
 133
 134 SEC("geneve_set_tunnel")
 135 int _geneve_set_tunnel(struct __sk_buff *skb)
 136 {
 137         int ret, ret2;
 138         struct bpf_tunnel_key key;
 139         struct geneve_opt gopt;
 140
 141         __builtin_memset(&key, 0x0, sizeof(key));
 142         key.remote_ipv4 = 0xac100164; /* 172.16.1.100 */
 143         key.tunnel_id = 2;
 144         key.tunnel_tos = 0;
 145         key.tunnel_ttl = 64;
 146
 147         __builtin_memset(&gopt, 0x0, sizeof(gopt));
 148         gopt.opt_class = 0x102; /* Open Virtual Networking (OVN) */
 149         gopt.type = 0x08;
 150         gopt.r1 = 1;
 151         gopt.r2 = 0;
 152         gopt.r3 = 1;
 153         gopt.length = 2; /* 4-byte multiple */
 154         *(int *) &gopt.opt_data = 0xdeadbeef;
 155
 156         ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key), BPF_F_ZERO_CSUM_TX);
 157         if (ret < 0) {
 158                 ERROR(ret);
 159                 return TC_ACT_SHOT;
 160         }
 161
 162         ret = bpf_skb_set_tunnel_opt(skb, &gopt, sizeof(gopt));
 163         if (ret < 0) {
 164                 ERROR(ret);
 165                 return TC_ACT_SHOT;
 166         }
 167
 168         return TC_ACT_OK;
 169 }
 170
 171 SEC("geneve_get_tunnel")
 172 int _geneve_get_tunnel(struct __sk_buff *skb)
 173 {
 174         int ret;
 175         struct bpf_tunnel_key key;
 176         struct geneve_opt gopt;
 177         char fmt[] = "key %d remote ip 0x%x geneve class 0x%x\n";
 178
 179         ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0);
 180         if (ret < 0) {
 181                 ERROR(ret);
 182                 return TC_ACT_SHOT;
 183         }
 184
 185         ret = bpf_skb_get_tunnel_opt(skb, &gopt, sizeof(gopt));
 186         if (ret < 0) {
 187                 ERROR(ret);
 188                 return TC_ACT_SHOT;
 189         }
 190
 191         bpf_trace_printk(fmt, sizeof(fmt),
 192                         key.tunnel_id, key.remote_ipv4, gopt.opt_class);
 193         return TC_ACT_OK;
 194 }
 195
 196 SEC("ipip_set_tunnel")
 197 int _ipip_set_tunnel(struct __sk_buff *skb)
 198 {
 199         struct bpf_tunnel_key key = {};
 200         void *data = (void *)(long)skb->data;
 201         struct iphdr *iph = data;
 202         struct tcphdr *tcp = data + sizeof(*iph);
 203         void *data_end = (void *)(long)skb->data_end;
 204         int ret;
 205
 206         /* single length check */
 207         if (data + sizeof(*iph) + sizeof(*tcp) > data_end) {
 208                 ERROR(1);
 209                 return TC_ACT_SHOT;
 210         }
 211
 212         key.tunnel_ttl = 64;
 213         if (iph->protocol == IPPROTO_ICMP) {
 214                 key.remote_ipv4 = 0xac100164; /* 172.16.1.100 */
 215         } else {
 216                 if (iph->protocol != IPPROTO_TCP || iph->ihl != 5)
 217                         return TC_ACT_SHOT;
 218
 219                 if (tcp->dest == htons(5200))
 220                         key.remote_ipv4 = 0xac100164; /* 172.16.1.100 */
 221                 else if (tcp->dest == htons(5201))
 222                         key.remote_ipv4 = 0xac100165; /* 172.16.1.101 */
 223                 else
 224                         return TC_ACT_SHOT;
 225         }
 226
 227         ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key), 0);
 228         if (ret < 0) {
 229                 ERROR(ret);
 230                 return TC_ACT_SHOT;
 231         }
 232
 233         return TC_ACT_OK;
 234 }
 235
 236 SEC("ipip_get_tunnel")
 237 int _ipip_get_tunnel(struct __sk_buff *skb)
 238 {
 239         int ret;
 240         struct bpf_tunnel_key key;
 241         char fmt[] = "remote ip 0x%x\n";
 242
 243         ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0);
 244         if (ret < 0) {
 245                 ERROR(ret);
 246                 return TC_ACT_SHOT;
 247         }
 248
 249         bpf_trace_printk(fmt, sizeof(fmt), key.remote_ipv4);
 250         return TC_ACT_OK;
 251 }
 252
 253 SEC("ipip6_set_tunnel")
 254 int _ipip6_set_tunnel(struct __sk_buff *skb)
 255 {
 256         struct bpf_tunnel_key key = {};
 257         void *data = (void *)(long)skb->data;
 258         struct iphdr *iph = data;
 259         struct tcphdr *tcp = data + sizeof(*iph);
 260         void *data_end = (void *)(long)skb->data_end;
 261         int ret;
 262
 263         /* single length check */
 264         if (data + sizeof(*iph) + sizeof(*tcp) > data_end) {
 265                 ERROR(1);
 266                 return TC_ACT_SHOT;
 267         }
 268
 269         key.remote_ipv6[0] = _htonl(0x2401db00);
 270         key.tunnel_ttl = 64;
 271
 272         if (iph->protocol == IPPROTO_ICMP) {
 273                 key.remote_ipv6[3] = _htonl(1);
 274         } else {
 275                 if (iph->protocol != IPPROTO_TCP || iph->ihl != 5) {
 276                         ERROR(iph->protocol);
 277                         return TC_ACT_SHOT;
 278                 }
 279
 280                 if (tcp->dest == htons(5200)) {
 281                         key.remote_ipv6[3] = _htonl(1);
 282                 } else if (tcp->dest == htons(5201)) {
 283                         key.remote_ipv6[3] = _htonl(2);
 284                 } else {
 285                         ERROR(tcp->dest);
 286                         return TC_ACT_SHOT;
 287                 }
 288         }
 289
 290         ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key), BPF_F_TUNINFO_IPV6);
 291         if (ret < 0) {
 292                 ERROR(ret);
 293                 return TC_ACT_SHOT;
 294         }
 295
 296         return TC_ACT_OK;
 297 }
 298
 299 SEC("ipip6_get_tunnel")
 300 int _ipip6_get_tunnel(struct __sk_buff *skb)
 301 {
 302         int ret;
 303         struct bpf_tunnel_key key;
 304         char fmt[] = "remote ip6 %x::%x\n";
 305
 306         ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), BPF_F_TUNINFO_IPV6);
 307         if (ret < 0) {
 308                 ERROR(ret);
 309                 return TC_ACT_SHOT;
 310         }
 311
 312         bpf_trace_printk(fmt, sizeof(fmt), _htonl(key.remote_ipv6[0]),
 313                          _htonl(key.remote_ipv6[3]));
 314         return TC_ACT_OK;
 315 }
 316
 317 SEC("ip6ip6_set_tunnel")
 318 int _ip6ip6_set_tunnel(struct __sk_buff *skb)
 319 {
 320         struct bpf_tunnel_key key = {};
 321         void *data = (void *)(long)skb->data;
 322         struct ipv6hdr *iph = data;
 323         struct tcphdr *tcp = data + sizeof(*iph);
 324         void *data_end = (void *)(long)skb->data_end;
 325         int ret;
 326
 327         /* single length check */
 328         if (data + sizeof(*iph) + sizeof(*tcp) > data_end) {
 329                 ERROR(1);
 330                 return TC_ACT_SHOT;
 331         }
 332
 333         key.remote_ipv6[0] = _htonl(0x2401db00);
 334         key.tunnel_ttl = 64;
 335
 336         if (iph->nexthdr == NEXTHDR_ICMP) {
 337                 key.remote_ipv6[3] = _htonl(1);
 338         } else {
 339                 if (iph->nexthdr != NEXTHDR_TCP) {
 340                         ERROR(iph->nexthdr);
 341                         return TC_ACT_SHOT;
 342                 }
 343
 344                 if (tcp->dest == htons(5200)) {
 345                         key.remote_ipv6[3] = _htonl(1);
 346                 } else if (tcp->dest == htons(5201)) {
 347                         key.remote_ipv6[3] = _htonl(2);
 348                 } else {
 349                         ERROR(tcp->dest);
 350                         return TC_ACT_SHOT;
 351                 }
 352         }
 353
 354         ret = bpf_skb_set_tunnel_key(skb, &key, sizeof(key), BPF_F_TUNINFO_IPV6);
 355         if (ret < 0) {
 356                 ERROR(ret);
 357                 return TC_ACT_SHOT;
 358         }
 359
 360         return TC_ACT_OK;
 361 }
 362
 363 SEC("ip6ip6_get_tunnel")
 364 int _ip6ip6_get_tunnel(struct __sk_buff *skb)
 365 {
 366         int ret;
 367         struct bpf_tunnel_key key;
 368         char fmt[] = "remote ip6 %x::%x\n";
 369
 370         ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), BPF_F_TUNINFO_IPV6);
 371         if (ret < 0) {
 372                 ERROR(ret);
 373                 return TC_ACT_SHOT;
 374         }
 375
 376         bpf_trace_printk(fmt, sizeof(fmt), _htonl(key.remote_ipv6[0]),
 377                          _htonl(key.remote_ipv6[3]));
 378         return TC_ACT_OK;
 379 }
 380
 381
 382 char _license[] SEC("license") = "GPL";