tools/include/uapi/linux/bpf.h

   1 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
   2  *
   3  * This program is free software; you can redistribute it and/or
   4  * modify it under the terms of version 2 of the GNU General Public
   5  * License as published by the Free Software Foundation.
   6  */
   7 #ifndef _UAPI__LINUX_BPF_H__
   8 #define _UAPI__LINUX_BPF_H__
   9
  10 #include <linux/types.h>
  11 #include <linux/bpf_common.h>
  12
  13 /* Extended instruction set based on top of classic BPF */
  14
  15 /* instruction classes */
  16 #define BPF_ALU64       0x07    /* alu mode in double word width */
  17
  18 /* ld/ldx fields */
  19 #define BPF_DW          0x18    /* double word */
  20 #define BPF_XADD        0xc0    /* exclusive add */
  21
  22 /* alu/jmp fields */
  23 #define BPF_MOV         0xb0    /* mov reg to reg */
  24 #define BPF_ARSH        0xc0    /* sign extending arithmetic shift right */
  25
  26 /* change endianness of a register */
  27 #define BPF_END         0xd0    /* flags for endianness conversion: */
  28 #define BPF_TO_LE       0x00    /* convert to little-endian */
  29 #define BPF_TO_BE       0x08    /* convert to big-endian */
  30 #define BPF_FROM_LE     BPF_TO_LE
  31 #define BPF_FROM_BE     BPF_TO_BE
  32
  33 #define BPF_JNE         0x50    /* jump != */
  34 #define BPF_JSGT        0x60    /* SGT is signed '>', GT in x86 */
  35 #define BPF_JSGE        0x70    /* SGE is signed '>=', GE in x86 */
  36 #define BPF_CALL        0x80    /* function call */
  37 #define BPF_EXIT        0x90    /* function return */
  38
  39 /* Register numbers */
  40 enum {
  41         BPF_REG_0 = 0,
  42         BPF_REG_1,
  43         BPF_REG_2,
  44         BPF_REG_3,
  45         BPF_REG_4,
  46         BPF_REG_5,
  47         BPF_REG_6,
  48         BPF_REG_7,
  49         BPF_REG_8,
  50         BPF_REG_9,
  51         BPF_REG_10,
  52         __MAX_BPF_REG,
  53 };
  54
  55 /* BPF has 10 general purpose 64-bit registers and stack frame. */
  56 #define MAX_BPF_REG     __MAX_BPF_REG
  57
  58 struct bpf_insn {
  59         __u8    code;           /* opcode */
  60         __u8    dst_reg:4;      /* dest register */
  61         __u8    src_reg:4;      /* source register */
  62         __s16   off;            /* signed offset */
  63         __s32   imm;            /* signed immediate constant */
  64 };
  65
  66 /* BPF syscall commands, see bpf(2) man-page for details. */
  67 enum bpf_cmd {
  68         BPF_MAP_CREATE,
  69         BPF_MAP_LOOKUP_ELEM,
  70         BPF_MAP_UPDATE_ELEM,
  71         BPF_MAP_DELETE_ELEM,
  72         BPF_MAP_GET_NEXT_KEY,
  73         BPF_PROG_LOAD,
  74         BPF_OBJ_PIN,
  75         BPF_OBJ_GET,
  76 };
  77
  78 enum bpf_map_type {
  79         BPF_MAP_TYPE_UNSPEC,
  80         BPF_MAP_TYPE_HASH,
  81         BPF_MAP_TYPE_ARRAY,
  82         BPF_MAP_TYPE_PROG_ARRAY,
  83         BPF_MAP_TYPE_PERF_EVENT_ARRAY,
  84         BPF_MAP_TYPE_PERCPU_HASH,
  85         BPF_MAP_TYPE_PERCPU_ARRAY,
  86         BPF_MAP_TYPE_STACK_TRACE,
  87         BPF_MAP_TYPE_CGROUP_ARRAY,
  88 };
  89
  90 enum bpf_prog_type {
  91         BPF_PROG_TYPE_UNSPEC,
  92         BPF_PROG_TYPE_SOCKET_FILTER,
  93         BPF_PROG_TYPE_KPROBE,
  94         BPF_PROG_TYPE_SCHED_CLS,
  95         BPF_PROG_TYPE_SCHED_ACT,
  96         BPF_PROG_TYPE_TRACEPOINT,
  97         BPF_PROG_TYPE_XDP,
  98 };
  99
 100 #define BPF_PSEUDO_MAP_FD       1
 101
 102 /* flags for BPF_MAP_UPDATE_ELEM command */
 103 #define BPF_ANY         0 /* create new element or update existing */
 104 #define BPF_NOEXIST     1 /* create new element if it didn't exist */
 105 #define BPF_EXIST       2 /* update existing element */
 106
 107 #define BPF_F_NO_PREALLOC       (1U << 0)
 108
 109 union bpf_attr {
 110         struct { /* anonymous struct used by BPF_MAP_CREATE command */
 111                 __u32   map_type;       /* one of enum bpf_map_type */
 112                 __u32   key_size;       /* size of key in bytes */
 113                 __u32   value_size;     /* size of value in bytes */
 114                 __u32   max_entries;    /* max number of entries in a map */
 115                 __u32   map_flags;      /* prealloc or not */
 116         };
 117
 118         struct { /* anonymous struct used by BPF_MAP_*_ELEM commands */
 119                 __u32           map_fd;
 120                 __aligned_u64   key;
 121                 union {
 122                         __aligned_u64 value;
 123                         __aligned_u64 next_key;
 124                 };
 125                 __u64           flags;
 126         };
 127
 128         struct { /* anonymous struct used by BPF_PROG_LOAD command */
 129                 __u32           prog_type;      /* one of enum bpf_prog_type */
 130                 __u32           insn_cnt;
 131                 __aligned_u64   insns;
 132                 __aligned_u64   license;
 133                 __u32           log_level;      /* verbosity level of verifier */
 134                 __u32           log_size;       /* size of user buffer */
 135                 __aligned_u64   log_buf;        /* user supplied buffer */
 136                 __u32           kern_version;   /* checked when prog_type=kprobe */
 137         };
 138
 139         struct { /* anonymous struct used by BPF_OBJ_* commands */
 140                 __aligned_u64   pathname;
 141                 __u32           bpf_fd;
 142         };
 143 } __attribute__((aligned(8)));
 144
 145 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
 146  * function eBPF program intends to call
 147  */
 148 enum bpf_func_id {
 149         BPF_FUNC_unspec,
 150         BPF_FUNC_map_lookup_elem, /* void *map_lookup_elem(&map, &key) */
 151         BPF_FUNC_map_update_elem, /* int map_update_elem(&map, &key, &value, flags) */
 152         BPF_FUNC_map_delete_elem, /* int map_delete_elem(&map, &key) */
 153         BPF_FUNC_probe_read,      /* int bpf_probe_read(void *dst, int size, void *src) */
 154         BPF_FUNC_ktime_get_ns,    /* u64 bpf_ktime_get_ns(void) */
 155         BPF_FUNC_trace_printk,    /* int bpf_trace_printk(const char *fmt, int fmt_size, ...) */
 156         BPF_FUNC_get_prandom_u32, /* u32 prandom_u32(void) */
 157         BPF_FUNC_get_smp_processor_id, /* u32 raw_smp_processor_id(void) */
 158
 159         /**
 160          * skb_store_bytes(skb, offset, from, len, flags) - store bytes into packet
 161          * @skb: pointer to skb
 162          * @offset: offset within packet from skb->mac_header
 163          * @from: pointer where to copy bytes from
 164          * @len: number of bytes to store into packet
 165          * @flags: bit 0 - if true, recompute skb->csum
 166          *         other bits - reserved
 167          * Return: 0 on success
 168          */
 169         BPF_FUNC_skb_store_bytes,
 170
 171         /**
 172          * l3_csum_replace(skb, offset, from, to, flags) - recompute IP checksum
 173          * @skb: pointer to skb
 174          * @offset: offset within packet where IP checksum is located
 175          * @from: old value of header field
 176          * @to: new value of header field
 177          * @flags: bits 0-3 - size of header field
 178          *         other bits - reserved
 179          * Return: 0 on success
 180          */
 181         BPF_FUNC_l3_csum_replace,
 182
 183         /**
 184          * l4_csum_replace(skb, offset, from, to, flags) - recompute TCP/UDP checksum
 185          * @skb: pointer to skb
 186          * @offset: offset within packet where TCP/UDP checksum is located
 187          * @from: old value of header field
 188          * @to: new value of header field
 189          * @flags: bits 0-3 - size of header field
 190          *         bit 4 - is pseudo header
 191          *         other bits - reserved
 192          * Return: 0 on success
 193          */
 194         BPF_FUNC_l4_csum_replace,
 195
 196         /**
 197          * bpf_tail_call(ctx, prog_array_map, index) - jump into another BPF program
 198          * @ctx: context pointer passed to next program
 199          * @prog_array_map: pointer to map which type is BPF_MAP_TYPE_PROG_ARRAY
 200          * @index: index inside array that selects specific program to run
 201          * Return: 0 on success
 202          */
 203         BPF_FUNC_tail_call,
 204
 205         /**
 206          * bpf_clone_redirect(skb, ifindex, flags) - redirect to another netdev
 207          * @skb: pointer to skb
 208          * @ifindex: ifindex of the net device
 209          * @flags: bit 0 - if set, redirect to ingress instead of egress
 210          *         other bits - reserved
 211          * Return: 0 on success
 212          */
 213         BPF_FUNC_clone_redirect,
 214
 215         /**
 216          * u64 bpf_get_current_pid_tgid(void)
 217          * Return: current->tgid << 32 | current->pid
 218          */
 219         BPF_FUNC_get_current_pid_tgid,
 220
 221         /**
 222          * u64 bpf_get_current_uid_gid(void)
 223          * Return: current_gid << 32 | current_uid
 224          */
 225         BPF_FUNC_get_current_uid_gid,
 226
 227         /**
 228          * bpf_get_current_comm(char *buf, int size_of_buf)
 229          * stores current->comm into buf
 230          * Return: 0 on success
 231          */
 232         BPF_FUNC_get_current_comm,
 233
 234         /**
 235          * bpf_get_cgroup_classid(skb) - retrieve a proc's classid
 236          * @skb: pointer to skb
 237          * Return: classid if != 0
 238          */
 239         BPF_FUNC_get_cgroup_classid,
 240         BPF_FUNC_skb_vlan_push, /* bpf_skb_vlan_push(skb, vlan_proto, vlan_tci) */
 241         BPF_FUNC_skb_vlan_pop,  /* bpf_skb_vlan_pop(skb) */
 242
 243         /**
 244          * bpf_skb_[gs]et_tunnel_key(skb, key, size, flags)
 245          * retrieve or populate tunnel metadata
 246          * @skb: pointer to skb
 247          * @key: pointer to 'struct bpf_tunnel_key'
 248          * @size: size of 'struct bpf_tunnel_key'
 249          * @flags: room for future extensions
 250          * Retrun: 0 on success
 251          */
 252         BPF_FUNC_skb_get_tunnel_key,
 253         BPF_FUNC_skb_set_tunnel_key,
 254         BPF_FUNC_perf_event_read,       /* u64 bpf_perf_event_read(&map, index) */
 255         /**
 256          * bpf_redirect(ifindex, flags) - redirect to another netdev
 257          * @ifindex: ifindex of the net device
 258          * @flags: bit 0 - if set, redirect to ingress instead of egress
 259          *         other bits - reserved
 260          * Return: TC_ACT_REDIRECT
 261          */
 262         BPF_FUNC_redirect,
 263
 264         /**
 265          * bpf_get_route_realm(skb) - retrieve a dst's tclassid
 266          * @skb: pointer to skb
 267          * Return: realm if != 0
 268          */
 269         BPF_FUNC_get_route_realm,
 270
 271         /**
 272          * bpf_perf_event_output(ctx, map, index, data, size) - output perf raw sample
 273          * @ctx: struct pt_regs*
 274          * @map: pointer to perf_event_array map
 275          * @index: index of event in the map
 276          * @data: data on stack to be output as raw data
 277          * @size: size of data
 278          * Return: 0 on success
 279          */
 280         BPF_FUNC_perf_event_output,
 281         BPF_FUNC_skb_load_bytes,
 282
 283         /**
 284          * bpf_get_stackid(ctx, map, flags) - walk user or kernel stack and return id
 285          * @ctx: struct pt_regs*
 286          * @map: pointer to stack_trace map
 287          * @flags: bits 0-7 - numer of stack frames to skip
 288          *         bit 8 - collect user stack instead of kernel
 289          *         bit 9 - compare stacks by hash only
 290          *         bit 10 - if two different stacks hash into the same stackid
 291          *                  discard old
 292          *         other bits - reserved
 293          * Return: >= 0 stackid on success or negative error
 294          */
 295         BPF_FUNC_get_stackid,
 296
 297         /**
 298          * bpf_csum_diff(from, from_size, to, to_size, seed) - calculate csum diff
 299          * @from: raw from buffer
 300          * @from_size: length of from buffer
 301          * @to: raw to buffer
 302          * @to_size: length of to buffer
 303          * @seed: optional seed
 304          * Return: csum result
 305          */
 306         BPF_FUNC_csum_diff,
 307
 308         /**
 309          * bpf_skb_[gs]et_tunnel_opt(skb, opt, size)
 310          * retrieve or populate tunnel options metadata
 311          * @skb: pointer to skb
 312          * @opt: pointer to raw tunnel option data
 313          * @size: size of @opt
 314          * Return: 0 on success for set, option size for get
 315          */
 316         BPF_FUNC_skb_get_tunnel_opt,
 317         BPF_FUNC_skb_set_tunnel_opt,
 318
 319         /**
 320          * bpf_skb_change_proto(skb, proto, flags)
 321          * Change protocol of the skb. Currently supported is
 322          * v4 -> v6, v6 -> v4 transitions. The helper will also
 323          * resize the skb. eBPF program is expected to fill the
 324          * new headers via skb_store_bytes and lX_csum_replace.
 325          * @skb: pointer to skb
 326          * @proto: new skb->protocol type
 327          * @flags: reserved
 328          * Return: 0 on success or negative error
 329          */
 330         BPF_FUNC_skb_change_proto,
 331
 332         /**
 333          * bpf_skb_change_type(skb, type)
 334          * Change packet type of skb.
 335          * @skb: pointer to skb
 336          * @type: new skb->pkt_type type
 337          * Return: 0 on success or negative error
 338          */
 339         BPF_FUNC_skb_change_type,
 340
 341         /**
 342          * bpf_skb_in_cgroup(skb, map, index) - Check cgroup2 membership of skb
 343          * @skb: pointer to skb
 344          * @map: pointer to bpf_map in BPF_MAP_TYPE_CGROUP_ARRAY type
 345          * @index: index of the cgroup in the bpf_map
 346          * Return:
 347          *   == 0 skb failed the cgroup2 descendant test
 348          *   == 1 skb succeeded the cgroup2 descendant test
 349          *    < 0 error
 350          */
 351         BPF_FUNC_skb_in_cgroup,
 352
 353         /**
 354          * bpf_get_hash_recalc(skb)
 355          * Retrieve and possibly recalculate skb->hash.
 356          * @skb: pointer to skb
 357          * Return: hash
 358          */
 359         BPF_FUNC_get_hash_recalc,
 360
 361         /**
 362          * u64 bpf_get_current_task(void)
 363          * Returns current task_struct
 364          * Return: current
 365          */
 366         BPF_FUNC_get_current_task,
 367
 368         /**
 369          * bpf_probe_write_user(void *dst, void *src, int len)
 370          * safely attempt to write to a location
 371          * @dst: destination address in userspace
 372          * @src: source address on stack
 373          * @len: number of bytes to copy
 374          * Return: 0 on success or negative error
 375          */
 376         BPF_FUNC_probe_write_user,
 377
 378         __BPF_FUNC_MAX_ID,
 379 };
 380
 381 /* All flags used by eBPF helper functions, placed here. */
 382
 383 /* BPF_FUNC_skb_store_bytes flags. */
 384 #define BPF_F_RECOMPUTE_CSUM            (1ULL << 0)
 385 #define BPF_F_INVALIDATE_HASH           (1ULL << 1)
 386
 387 /* BPF_FUNC_l3_csum_replace and BPF_FUNC_l4_csum_replace flags.
 388  * First 4 bits are for passing the header field size.
 389  */
 390 #define BPF_F_HDR_FIELD_MASK            0xfULL
 391
 392 /* BPF_FUNC_l4_csum_replace flags. */
 393 #define BPF_F_PSEUDO_HDR                (1ULL << 4)
 394 #define BPF_F_MARK_MANGLED_0            (1ULL << 5)
 395
 396 /* BPF_FUNC_clone_redirect and BPF_FUNC_redirect flags. */
 397 #define BPF_F_INGRESS                   (1ULL << 0)
 398
 399 /* BPF_FUNC_skb_set_tunnel_key and BPF_FUNC_skb_get_tunnel_key flags. */
 400 #define BPF_F_TUNINFO_IPV6              (1ULL << 0)
 401
 402 /* BPF_FUNC_get_stackid flags. */
 403 #define BPF_F_SKIP_FIELD_MASK           0xffULL
 404 #define BPF_F_USER_STACK                (1ULL << 8)
 405 #define BPF_F_FAST_STACK_CMP            (1ULL << 9)
 406 #define BPF_F_REUSE_STACKID             (1ULL << 10)
 407
 408 /* BPF_FUNC_skb_set_tunnel_key flags. */
 409 #define BPF_F_ZERO_CSUM_TX              (1ULL << 1)
 410 #define BPF_F_DONT_FRAGMENT             (1ULL << 2)
 411
 412 /* BPF_FUNC_perf_event_output and BPF_FUNC_perf_event_read flags. */
 413 #define BPF_F_INDEX_MASK                0xffffffffULL
 414 #define BPF_F_CURRENT_CPU               BPF_F_INDEX_MASK
 415 /* BPF_FUNC_perf_event_output for sk_buff input context. */
 416 #define BPF_F_CTXLEN_MASK               (0xfffffULL << 32)
 417
 418 /* user accessible mirror of in-kernel sk_buff.
 419  * new fields can only be added to the end of this structure
 420  */
 421 struct __sk_buff {
 422         __u32 len;
 423         __u32 pkt_type;
 424         __u32 mark;
 425         __u32 queue_mapping;
 426         __u32 protocol;
 427         __u32 vlan_present;
 428         __u32 vlan_tci;
 429         __u32 vlan_proto;
 430         __u32 priority;
 431         __u32 ingress_ifindex;
 432         __u32 ifindex;
 433         __u32 tc_index;
 434         __u32 cb[5];
 435         __u32 hash;
 436         __u32 tc_classid;
 437         __u32 data;
 438         __u32 data_end;
 439 };
 440
 441 struct bpf_tunnel_key {
 442         __u32 tunnel_id;
 443         union {
 444                 __u32 remote_ipv4;
 445                 __u32 remote_ipv6[4];
 446         };
 447         __u8 tunnel_tos;
 448         __u8 tunnel_ttl;
 449         __u16 tunnel_ext;
 450         __u32 tunnel_label;
 451 };
 452
 453 /* User return codes for XDP prog type.
 454  * A valid XDP program must return one of these defined values. All other
 455  * return codes are reserved for future use. Unknown return codes will result
 456  * in packet drop.
 457  */
 458 enum xdp_action {
 459         XDP_ABORTED = 0,
 460         XDP_DROP,
 461         XDP_PASS,
 462         XDP_TX,
 463 };
 464
 465 /* user accessible metadata for XDP packet hook
 466  * new fields must be added to the end of this structure
 467  */
 468 struct xdp_md {
 469         __u32 data;
 470         __u32 data_end;
 471 };
 472
 473 #endif /* _UAPI__LINUX_BPF_H__ */