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 18 /* Sockmap sample program connects a client and a backend together 19 * using cgroups. 20 * 21 * client:X <---> frontend:80 client:X <---> backend:80 22 * 23 * For simplicity we hard code values here and bind 1:1. The hard 24 * coded values are part of the setup in sockmap.sh script that 25 * is associated with this BPF program. 26 * 27 * The bpf_printk is verbose and prints information as connections 28 * are established and verdicts are decided. 29 */ 30 31 struct { 32 __uint(type, TEST_MAP_TYPE); 33 __uint(max_entries, 20); 34 __uint(key_size, sizeof(int)); 35 __uint(value_size, sizeof(int)); 36 } sock_map SEC(".maps"); 37 38 struct { 39 __uint(type, TEST_MAP_TYPE); 40 __uint(max_entries, 20); 41 __uint(key_size, sizeof(int)); 42 __uint(value_size, sizeof(int)); 43 } sock_map_txmsg SEC(".maps"); 44 45 struct { 46 __uint(type, TEST_MAP_TYPE); 47 __uint(max_entries, 20); 48 __uint(key_size, sizeof(int)); 49 __uint(value_size, sizeof(int)); 50 } sock_map_redir SEC(".maps"); 51 52 struct { 53 __uint(type, BPF_MAP_TYPE_ARRAY); 54 __uint(max_entries, 1); 55 __type(key, int); 56 __type(value, int); 57 } sock_apply_bytes SEC(".maps"); 58 59 struct { 60 __uint(type, BPF_MAP_TYPE_ARRAY); 61 __uint(max_entries, 1); 62 __type(key, int); 63 __type(value, int); 64 } sock_cork_bytes SEC(".maps"); 65 66 struct { 67 __uint(type, BPF_MAP_TYPE_ARRAY); 68 __uint(max_entries, 6); 69 __type(key, int); 70 __type(value, int); 71 } sock_bytes SEC(".maps"); 72 73 struct { 74 __uint(type, BPF_MAP_TYPE_ARRAY); 75 __uint(max_entries, 1); 76 __type(key, int); 77 __type(value, int); 78 } sock_redir_flags SEC(".maps"); 79 80 struct { 81 __uint(type, BPF_MAP_TYPE_ARRAY); 82 __uint(max_entries, 3); 83 __type(key, int); 84 __type(value, int); 85 } sock_skb_opts SEC(".maps"); 86 87 struct { 88 __uint(type, TEST_MAP_TYPE); 89 __uint(max_entries, 20); 90 __uint(key_size, sizeof(int)); 91 __uint(value_size, sizeof(int)); 92 } tls_sock_map SEC(".maps"); 93 94 SEC("sk_skb1") 95 int bpf_prog1(struct __sk_buff *skb) 96 { 97 int *f, two = 2; 98 99 f = bpf_map_lookup_elem(&sock_skb_opts, &two); 100 if (f && *f) { 101 return *f; 102 } 103 return skb->len; 104 } 105 106 SEC("sk_skb2") 107 int bpf_prog2(struct __sk_buff *skb) 108 { 109 __u32 lport = skb->local_port; 110 __u32 rport = skb->remote_port; 111 int len, *f, ret, zero = 0; 112 __u64 flags = 0; 113 114 if (lport == 10000) 115 ret = 10; 116 else 117 ret = 1; 118 119 len = (__u32)skb->data_end - (__u32)skb->data; 120 f = bpf_map_lookup_elem(&sock_skb_opts, &zero); 121 if (f && *f) { 122 ret = 3; 123 flags = *f; 124 } 125 126 #ifdef SOCKMAP 127 return bpf_sk_redirect_map(skb, &sock_map, ret, flags); 128 #else 129 return bpf_sk_redirect_hash(skb, &sock_map, &ret, flags); 130 #endif 131 132 } 133 134 SEC("sk_skb3") 135 int bpf_prog3(struct __sk_buff *skb) 136 { 137 const int one = 1; 138 int err, *f, ret = SK_PASS; 139 void *data_end; 140 char *c; 141 142 err = bpf_skb_pull_data(skb, 19); 143 if (err) 144 goto tls_out; 145 146 c = (char *)(long)skb->data; 147 data_end = (void *)(long)skb->data_end; 148 149 if (c + 18 < data_end) 150 memcpy(&c[13], "PASS", 4); 151 f = bpf_map_lookup_elem(&sock_skb_opts, &one); 152 if (f && *f) { 153 __u64 flags = 0; 154 155 ret = 0; 156 flags = *f; 157 #ifdef SOCKMAP 158 return bpf_sk_redirect_map(skb, &tls_sock_map, ret, flags); 159 #else 160 return bpf_sk_redirect_hash(skb, &tls_sock_map, &ret, flags); 161 #endif 162 } 163 164 f = bpf_map_lookup_elem(&sock_skb_opts, &one); 165 if (f && *f) 166 ret = SK_DROP; 167 tls_out: 168 return ret; 169 } 170 171 SEC("sockops") 172 int bpf_sockmap(struct bpf_sock_ops *skops) 173 { 174 __u32 lport, rport; 175 int op, err = 0, index, key, ret; 176 177 178 op = (int) skops->op; 179 180 switch (op) { 181 case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB: 182 lport = skops->local_port; 183 rport = skops->remote_port; 184 185 if (lport == 10000) { 186 ret = 1; 187 #ifdef SOCKMAP 188 err = bpf_sock_map_update(skops, &sock_map, &ret, 189 BPF_NOEXIST); 190 #else 191 err = bpf_sock_hash_update(skops, &sock_map, &ret, 192 BPF_NOEXIST); 193 #endif 194 } 195 break; 196 case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB: 197 lport = skops->local_port; 198 rport = skops->remote_port; 199 200 if (bpf_ntohl(rport) == 10001) { 201 ret = 10; 202 #ifdef SOCKMAP 203 err = bpf_sock_map_update(skops, &sock_map, &ret, 204 BPF_NOEXIST); 205 #else 206 err = bpf_sock_hash_update(skops, &sock_map, &ret, 207 BPF_NOEXIST); 208 #endif 209 } 210 break; 211 default: 212 break; 213 } 214 215 return 0; 216 } 217 218 SEC("sk_msg1") 219 int bpf_prog4(struct sk_msg_md *msg) 220 { 221 int *bytes, zero = 0, one = 1, two = 2, three = 3, four = 4, five = 5; 222 int *start, *end, *start_push, *end_push, *start_pop, *pop; 223 224 bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero); 225 if (bytes) 226 bpf_msg_apply_bytes(msg, *bytes); 227 bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero); 228 if (bytes) 229 bpf_msg_cork_bytes(msg, *bytes); 230 start = bpf_map_lookup_elem(&sock_bytes, &zero); 231 end = bpf_map_lookup_elem(&sock_bytes, &one); 232 if (start && end) 233 bpf_msg_pull_data(msg, *start, *end, 0); 234 start_push = bpf_map_lookup_elem(&sock_bytes, &two); 235 end_push = bpf_map_lookup_elem(&sock_bytes, &three); 236 if (start_push && end_push) 237 bpf_msg_push_data(msg, *start_push, *end_push, 0); 238 start_pop = bpf_map_lookup_elem(&sock_bytes, &four); 239 pop = bpf_map_lookup_elem(&sock_bytes, &five); 240 if (start_pop && pop) 241 bpf_msg_pop_data(msg, *start_pop, *pop, 0); 242 return SK_PASS; 243 } 244 245 SEC("sk_msg2") 246 int bpf_prog6(struct sk_msg_md *msg) 247 { 248 int zero = 0, one = 1, two = 2, three = 3, four = 4, five = 5, key = 0; 249 int *bytes, *start, *end, *start_push, *end_push, *start_pop, *pop, *f; 250 __u64 flags = 0; 251 252 bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero); 253 if (bytes) 254 bpf_msg_apply_bytes(msg, *bytes); 255 bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero); 256 if (bytes) 257 bpf_msg_cork_bytes(msg, *bytes); 258 259 start = bpf_map_lookup_elem(&sock_bytes, &zero); 260 end = bpf_map_lookup_elem(&sock_bytes, &one); 261 if (start && end) 262 bpf_msg_pull_data(msg, *start, *end, 0); 263 264 start_push = bpf_map_lookup_elem(&sock_bytes, &two); 265 end_push = bpf_map_lookup_elem(&sock_bytes, &three); 266 if (start_push && end_push) 267 bpf_msg_push_data(msg, *start_push, *end_push, 0); 268 269 start_pop = bpf_map_lookup_elem(&sock_bytes, &four); 270 pop = bpf_map_lookup_elem(&sock_bytes, &five); 271 if (start_pop && pop) 272 bpf_msg_pop_data(msg, *start_pop, *pop, 0); 273 274 f = bpf_map_lookup_elem(&sock_redir_flags, &zero); 275 if (f && *f) { 276 key = 2; 277 flags = *f; 278 } 279 #ifdef SOCKMAP 280 return bpf_msg_redirect_map(msg, &sock_map_redir, key, flags); 281 #else 282 return bpf_msg_redirect_hash(msg, &sock_map_redir, &key, flags); 283 #endif 284 } 285 286 SEC("sk_msg3") 287 int bpf_prog8(struct sk_msg_md *msg) 288 { 289 void *data_end = (void *)(long) msg->data_end; 290 void *data = (void *)(long) msg->data; 291 int ret = 0, *bytes, zero = 0; 292 293 bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero); 294 if (bytes) { 295 ret = bpf_msg_apply_bytes(msg, *bytes); 296 if (ret) 297 return SK_DROP; 298 } else { 299 return SK_DROP; 300 } 301 return SK_PASS; 302 } 303 SEC("sk_msg4") 304 int bpf_prog9(struct sk_msg_md *msg) 305 { 306 void *data_end = (void *)(long) msg->data_end; 307 void *data = (void *)(long) msg->data; 308 int ret = 0, *bytes, zero = 0; 309 310 bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero); 311 if (bytes) { 312 if (((__u64)data_end - (__u64)data) >= *bytes) 313 return SK_PASS; 314 ret = bpf_msg_cork_bytes(msg, *bytes); 315 if (ret) 316 return SK_DROP; 317 } 318 return SK_PASS; 319 } 320 321 SEC("sk_msg5") 322 int bpf_prog10(struct sk_msg_md *msg) 323 { 324 int *bytes, *start, *end, *start_push, *end_push, *start_pop, *pop; 325 int zero = 0, one = 1, two = 2, three = 3, four = 4, five = 5; 326 327 bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero); 328 if (bytes) 329 bpf_msg_apply_bytes(msg, *bytes); 330 bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero); 331 if (bytes) 332 bpf_msg_cork_bytes(msg, *bytes); 333 start = bpf_map_lookup_elem(&sock_bytes, &zero); 334 end = bpf_map_lookup_elem(&sock_bytes, &one); 335 if (start && end) 336 bpf_msg_pull_data(msg, *start, *end, 0); 337 start_push = bpf_map_lookup_elem(&sock_bytes, &two); 338 end_push = bpf_map_lookup_elem(&sock_bytes, &three); 339 if (start_push && end_push) 340 bpf_msg_push_data(msg, *start_push, *end_push, 0); 341 start_pop = bpf_map_lookup_elem(&sock_bytes, &four); 342 pop = bpf_map_lookup_elem(&sock_bytes, &five); 343 if (start_pop && pop) 344 bpf_msg_pop_data(msg, *start_pop, *pop, 0); 345 return SK_DROP; 346 } 347 348 int _version SEC("version") = 1; 349 char _license[] SEC("license") = "GPL"; 350