2 * Linux Socket Filter - Kernel level socket filtering
4 * Based on the design of the Berkeley Packet Filter. The new
5 * internal format has been designed by PLUMgrid:
7 * Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com
11 * Jay Schulist <jschlst@samba.org>
12 * Alexei Starovoitov <ast@plumgrid.com>
13 * Daniel Borkmann <dborkman@redhat.com>
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License
17 * as published by the Free Software Foundation; either version
18 * 2 of the License, or (at your option) any later version.
20 * Andi Kleen - Fix a few bad bugs and races.
21 * Kris Katterjohn - Added many additional checks in bpf_check_classic()
24 #include <linux/module.h>
25 #include <linux/types.h>
27 #include <linux/fcntl.h>
28 #include <linux/socket.h>
30 #include <linux/inet.h>
31 #include <linux/netdevice.h>
32 #include <linux/if_packet.h>
33 #include <linux/gfp.h>
35 #include <net/protocol.h>
36 #include <net/netlink.h>
37 #include <linux/skbuff.h>
39 #include <net/flow_dissector.h>
40 #include <linux/errno.h>
41 #include <linux/timer.h>
42 #include <asm/uaccess.h>
43 #include <asm/unaligned.h>
44 #include <linux/filter.h>
45 #include <linux/ratelimit.h>
46 #include <linux/seccomp.h>
47 #include <linux/if_vlan.h>
48 #include <linux/bpf.h>
49 #include <net/sch_generic.h>
50 #include <net/cls_cgroup.h>
51 #include <net/dst_metadata.h>
53 #include <net/sock_reuseport.h>
56 * sk_filter_trim_cap - run a packet through a socket filter
57 * @sk: sock associated with &sk_buff
58 * @skb: buffer to filter
59 * @cap: limit on how short the eBPF program may trim the packet
61 * Run the eBPF program and then cut skb->data to correct size returned by
62 * the program. If pkt_len is 0 we toss packet. If skb->len is smaller
63 * than pkt_len we keep whole skb->data. This is the socket level
64 * wrapper to BPF_PROG_RUN. It returns 0 if the packet should
65 * be accepted or -EPERM if the packet should be tossed.
68 int sk_filter_trim_cap(struct sock
*sk
, struct sk_buff
*skb
, unsigned int cap
)
71 struct sk_filter
*filter
;
74 * If the skb was allocated from pfmemalloc reserves, only
75 * allow SOCK_MEMALLOC sockets to use it as this socket is
78 if (skb_pfmemalloc(skb
) && !sock_flag(sk
, SOCK_MEMALLOC
))
81 err
= security_sock_rcv_skb(sk
, skb
);
86 filter
= rcu_dereference(sk
->sk_filter
);
88 unsigned int pkt_len
= bpf_prog_run_save_cb(filter
->prog
, skb
);
89 err
= pkt_len
? pskb_trim(skb
, max(cap
, pkt_len
)) : -EPERM
;
95 EXPORT_SYMBOL(sk_filter_trim_cap
);
97 BPF_CALL_1(__skb_get_pay_offset
, struct sk_buff
*, skb
)
99 return skb_get_poff(skb
);
102 BPF_CALL_3(__skb_get_nlattr
, struct sk_buff
*, skb
, u32
, a
, u32
, x
)
106 if (skb_is_nonlinear(skb
))
109 if (skb
->len
< sizeof(struct nlattr
))
112 if (a
> skb
->len
- sizeof(struct nlattr
))
115 nla
= nla_find((struct nlattr
*) &skb
->data
[a
], skb
->len
- a
, x
);
117 return (void *) nla
- (void *) skb
->data
;
122 BPF_CALL_3(__skb_get_nlattr_nest
, struct sk_buff
*, skb
, u32
, a
, u32
, x
)
126 if (skb_is_nonlinear(skb
))
129 if (skb
->len
< sizeof(struct nlattr
))
132 if (a
> skb
->len
- sizeof(struct nlattr
))
135 nla
= (struct nlattr
*) &skb
->data
[a
];
136 if (nla
->nla_len
> skb
->len
- a
)
139 nla
= nla_find_nested(nla
, x
);
141 return (void *) nla
- (void *) skb
->data
;
146 BPF_CALL_0(__get_raw_cpu_id
)
148 return raw_smp_processor_id();
151 static const struct bpf_func_proto bpf_get_raw_smp_processor_id_proto
= {
152 .func
= __get_raw_cpu_id
,
154 .ret_type
= RET_INTEGER
,
157 static u32
convert_skb_access(int skb_field
, int dst_reg
, int src_reg
,
158 struct bpf_insn
*insn_buf
)
160 struct bpf_insn
*insn
= insn_buf
;
164 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, mark
) != 4);
166 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
167 offsetof(struct sk_buff
, mark
));
171 *insn
++ = BPF_LDX_MEM(BPF_B
, dst_reg
, src_reg
, PKT_TYPE_OFFSET());
172 *insn
++ = BPF_ALU32_IMM(BPF_AND
, dst_reg
, PKT_TYPE_MAX
);
173 #ifdef __BIG_ENDIAN_BITFIELD
174 *insn
++ = BPF_ALU32_IMM(BPF_RSH
, dst_reg
, 5);
179 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, queue_mapping
) != 2);
181 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
182 offsetof(struct sk_buff
, queue_mapping
));
185 case SKF_AD_VLAN_TAG
:
186 case SKF_AD_VLAN_TAG_PRESENT
:
187 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, vlan_tci
) != 2);
188 BUILD_BUG_ON(VLAN_TAG_PRESENT
!= 0x1000);
190 /* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
191 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
192 offsetof(struct sk_buff
, vlan_tci
));
193 if (skb_field
== SKF_AD_VLAN_TAG
) {
194 *insn
++ = BPF_ALU32_IMM(BPF_AND
, dst_reg
,
198 *insn
++ = BPF_ALU32_IMM(BPF_RSH
, dst_reg
, 12);
200 *insn
++ = BPF_ALU32_IMM(BPF_AND
, dst_reg
, 1);
205 return insn
- insn_buf
;
208 static bool convert_bpf_extensions(struct sock_filter
*fp
,
209 struct bpf_insn
**insnp
)
211 struct bpf_insn
*insn
= *insnp
;
215 case SKF_AD_OFF
+ SKF_AD_PROTOCOL
:
216 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, protocol
) != 2);
218 /* A = *(u16 *) (CTX + offsetof(protocol)) */
219 *insn
++ = BPF_LDX_MEM(BPF_H
, BPF_REG_A
, BPF_REG_CTX
,
220 offsetof(struct sk_buff
, protocol
));
221 /* A = ntohs(A) [emitting a nop or swap16] */
222 *insn
= BPF_ENDIAN(BPF_FROM_BE
, BPF_REG_A
, 16);
225 case SKF_AD_OFF
+ SKF_AD_PKTTYPE
:
226 cnt
= convert_skb_access(SKF_AD_PKTTYPE
, BPF_REG_A
, BPF_REG_CTX
, insn
);
230 case SKF_AD_OFF
+ SKF_AD_IFINDEX
:
231 case SKF_AD_OFF
+ SKF_AD_HATYPE
:
232 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device
, ifindex
) != 4);
233 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device
, type
) != 2);
235 *insn
++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff
, dev
),
236 BPF_REG_TMP
, BPF_REG_CTX
,
237 offsetof(struct sk_buff
, dev
));
238 /* if (tmp != 0) goto pc + 1 */
239 *insn
++ = BPF_JMP_IMM(BPF_JNE
, BPF_REG_TMP
, 0, 1);
240 *insn
++ = BPF_EXIT_INSN();
241 if (fp
->k
== SKF_AD_OFF
+ SKF_AD_IFINDEX
)
242 *insn
= BPF_LDX_MEM(BPF_W
, BPF_REG_A
, BPF_REG_TMP
,
243 offsetof(struct net_device
, ifindex
));
245 *insn
= BPF_LDX_MEM(BPF_H
, BPF_REG_A
, BPF_REG_TMP
,
246 offsetof(struct net_device
, type
));
249 case SKF_AD_OFF
+ SKF_AD_MARK
:
250 cnt
= convert_skb_access(SKF_AD_MARK
, BPF_REG_A
, BPF_REG_CTX
, insn
);
254 case SKF_AD_OFF
+ SKF_AD_RXHASH
:
255 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, hash
) != 4);
257 *insn
= BPF_LDX_MEM(BPF_W
, BPF_REG_A
, BPF_REG_CTX
,
258 offsetof(struct sk_buff
, hash
));
261 case SKF_AD_OFF
+ SKF_AD_QUEUE
:
262 cnt
= convert_skb_access(SKF_AD_QUEUE
, BPF_REG_A
, BPF_REG_CTX
, insn
);
266 case SKF_AD_OFF
+ SKF_AD_VLAN_TAG
:
267 cnt
= convert_skb_access(SKF_AD_VLAN_TAG
,
268 BPF_REG_A
, BPF_REG_CTX
, insn
);
272 case SKF_AD_OFF
+ SKF_AD_VLAN_TAG_PRESENT
:
273 cnt
= convert_skb_access(SKF_AD_VLAN_TAG_PRESENT
,
274 BPF_REG_A
, BPF_REG_CTX
, insn
);
278 case SKF_AD_OFF
+ SKF_AD_VLAN_TPID
:
279 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, vlan_proto
) != 2);
281 /* A = *(u16 *) (CTX + offsetof(vlan_proto)) */
282 *insn
++ = BPF_LDX_MEM(BPF_H
, BPF_REG_A
, BPF_REG_CTX
,
283 offsetof(struct sk_buff
, vlan_proto
));
284 /* A = ntohs(A) [emitting a nop or swap16] */
285 *insn
= BPF_ENDIAN(BPF_FROM_BE
, BPF_REG_A
, 16);
288 case SKF_AD_OFF
+ SKF_AD_PAY_OFFSET
:
289 case SKF_AD_OFF
+ SKF_AD_NLATTR
:
290 case SKF_AD_OFF
+ SKF_AD_NLATTR_NEST
:
291 case SKF_AD_OFF
+ SKF_AD_CPU
:
292 case SKF_AD_OFF
+ SKF_AD_RANDOM
:
294 *insn
++ = BPF_MOV64_REG(BPF_REG_ARG1
, BPF_REG_CTX
);
296 *insn
++ = BPF_MOV64_REG(BPF_REG_ARG2
, BPF_REG_A
);
298 *insn
++ = BPF_MOV64_REG(BPF_REG_ARG3
, BPF_REG_X
);
299 /* Emit call(arg1=CTX, arg2=A, arg3=X) */
301 case SKF_AD_OFF
+ SKF_AD_PAY_OFFSET
:
302 *insn
= BPF_EMIT_CALL(__skb_get_pay_offset
);
304 case SKF_AD_OFF
+ SKF_AD_NLATTR
:
305 *insn
= BPF_EMIT_CALL(__skb_get_nlattr
);
307 case SKF_AD_OFF
+ SKF_AD_NLATTR_NEST
:
308 *insn
= BPF_EMIT_CALL(__skb_get_nlattr_nest
);
310 case SKF_AD_OFF
+ SKF_AD_CPU
:
311 *insn
= BPF_EMIT_CALL(__get_raw_cpu_id
);
313 case SKF_AD_OFF
+ SKF_AD_RANDOM
:
314 *insn
= BPF_EMIT_CALL(bpf_user_rnd_u32
);
315 bpf_user_rnd_init_once();
320 case SKF_AD_OFF
+ SKF_AD_ALU_XOR_X
:
322 *insn
= BPF_ALU32_REG(BPF_XOR
, BPF_REG_A
, BPF_REG_X
);
326 /* This is just a dummy call to avoid letting the compiler
327 * evict __bpf_call_base() as an optimization. Placed here
328 * where no-one bothers.
330 BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0);
339 * bpf_convert_filter - convert filter program
340 * @prog: the user passed filter program
341 * @len: the length of the user passed filter program
342 * @new_prog: buffer where converted program will be stored
343 * @new_len: pointer to store length of converted program
345 * Remap 'sock_filter' style BPF instruction set to 'sock_filter_ext' style.
346 * Conversion workflow:
348 * 1) First pass for calculating the new program length:
349 * bpf_convert_filter(old_prog, old_len, NULL, &new_len)
351 * 2) 2nd pass to remap in two passes: 1st pass finds new
352 * jump offsets, 2nd pass remapping:
353 * new_prog = kmalloc(sizeof(struct bpf_insn) * new_len);
354 * bpf_convert_filter(old_prog, old_len, new_prog, &new_len);
356 static int bpf_convert_filter(struct sock_filter
*prog
, int len
,
357 struct bpf_insn
*new_prog
, int *new_len
)
359 int new_flen
= 0, pass
= 0, target
, i
;
360 struct bpf_insn
*new_insn
;
361 struct sock_filter
*fp
;
365 BUILD_BUG_ON(BPF_MEMWORDS
* sizeof(u32
) > MAX_BPF_STACK
);
366 BUILD_BUG_ON(BPF_REG_FP
+ 1 != MAX_BPF_REG
);
368 if (len
<= 0 || len
> BPF_MAXINSNS
)
372 addrs
= kcalloc(len
, sizeof(*addrs
),
373 GFP_KERNEL
| __GFP_NOWARN
);
382 /* Classic BPF related prologue emission. */
384 /* Classic BPF expects A and X to be reset first. These need
385 * to be guaranteed to be the first two instructions.
387 *new_insn
++ = BPF_ALU64_REG(BPF_XOR
, BPF_REG_A
, BPF_REG_A
);
388 *new_insn
++ = BPF_ALU64_REG(BPF_XOR
, BPF_REG_X
, BPF_REG_X
);
390 /* All programs must keep CTX in callee saved BPF_REG_CTX.
391 * In eBPF case it's done by the compiler, here we need to
392 * do this ourself. Initial CTX is present in BPF_REG_ARG1.
394 *new_insn
++ = BPF_MOV64_REG(BPF_REG_CTX
, BPF_REG_ARG1
);
399 for (i
= 0; i
< len
; fp
++, i
++) {
400 struct bpf_insn tmp_insns
[6] = { };
401 struct bpf_insn
*insn
= tmp_insns
;
404 addrs
[i
] = new_insn
- new_prog
;
407 /* All arithmetic insns and skb loads map as-is. */
408 case BPF_ALU
| BPF_ADD
| BPF_X
:
409 case BPF_ALU
| BPF_ADD
| BPF_K
:
410 case BPF_ALU
| BPF_SUB
| BPF_X
:
411 case BPF_ALU
| BPF_SUB
| BPF_K
:
412 case BPF_ALU
| BPF_AND
| BPF_X
:
413 case BPF_ALU
| BPF_AND
| BPF_K
:
414 case BPF_ALU
| BPF_OR
| BPF_X
:
415 case BPF_ALU
| BPF_OR
| BPF_K
:
416 case BPF_ALU
| BPF_LSH
| BPF_X
:
417 case BPF_ALU
| BPF_LSH
| BPF_K
:
418 case BPF_ALU
| BPF_RSH
| BPF_X
:
419 case BPF_ALU
| BPF_RSH
| BPF_K
:
420 case BPF_ALU
| BPF_XOR
| BPF_X
:
421 case BPF_ALU
| BPF_XOR
| BPF_K
:
422 case BPF_ALU
| BPF_MUL
| BPF_X
:
423 case BPF_ALU
| BPF_MUL
| BPF_K
:
424 case BPF_ALU
| BPF_DIV
| BPF_X
:
425 case BPF_ALU
| BPF_DIV
| BPF_K
:
426 case BPF_ALU
| BPF_MOD
| BPF_X
:
427 case BPF_ALU
| BPF_MOD
| BPF_K
:
428 case BPF_ALU
| BPF_NEG
:
429 case BPF_LD
| BPF_ABS
| BPF_W
:
430 case BPF_LD
| BPF_ABS
| BPF_H
:
431 case BPF_LD
| BPF_ABS
| BPF_B
:
432 case BPF_LD
| BPF_IND
| BPF_W
:
433 case BPF_LD
| BPF_IND
| BPF_H
:
434 case BPF_LD
| BPF_IND
| BPF_B
:
435 /* Check for overloaded BPF extension and
436 * directly convert it if found, otherwise
437 * just move on with mapping.
439 if (BPF_CLASS(fp
->code
) == BPF_LD
&&
440 BPF_MODE(fp
->code
) == BPF_ABS
&&
441 convert_bpf_extensions(fp
, &insn
))
444 *insn
= BPF_RAW_INSN(fp
->code
, BPF_REG_A
, BPF_REG_X
, 0, fp
->k
);
447 /* Jump transformation cannot use BPF block macros
448 * everywhere as offset calculation and target updates
449 * require a bit more work than the rest, i.e. jump
450 * opcodes map as-is, but offsets need adjustment.
453 #define BPF_EMIT_JMP \
455 if (target >= len || target < 0) \
457 insn->off = addrs ? addrs[target] - addrs[i] - 1 : 0; \
458 /* Adjust pc relative offset for 2nd or 3rd insn. */ \
459 insn->off -= insn - tmp_insns; \
462 case BPF_JMP
| BPF_JA
:
463 target
= i
+ fp
->k
+ 1;
464 insn
->code
= fp
->code
;
468 case BPF_JMP
| BPF_JEQ
| BPF_K
:
469 case BPF_JMP
| BPF_JEQ
| BPF_X
:
470 case BPF_JMP
| BPF_JSET
| BPF_K
:
471 case BPF_JMP
| BPF_JSET
| BPF_X
:
472 case BPF_JMP
| BPF_JGT
| BPF_K
:
473 case BPF_JMP
| BPF_JGT
| BPF_X
:
474 case BPF_JMP
| BPF_JGE
| BPF_K
:
475 case BPF_JMP
| BPF_JGE
| BPF_X
:
476 if (BPF_SRC(fp
->code
) == BPF_K
&& (int) fp
->k
< 0) {
477 /* BPF immediates are signed, zero extend
478 * immediate into tmp register and use it
481 *insn
++ = BPF_MOV32_IMM(BPF_REG_TMP
, fp
->k
);
483 insn
->dst_reg
= BPF_REG_A
;
484 insn
->src_reg
= BPF_REG_TMP
;
487 insn
->dst_reg
= BPF_REG_A
;
489 bpf_src
= BPF_SRC(fp
->code
);
490 insn
->src_reg
= bpf_src
== BPF_X
? BPF_REG_X
: 0;
493 /* Common case where 'jump_false' is next insn. */
495 insn
->code
= BPF_JMP
| BPF_OP(fp
->code
) | bpf_src
;
496 target
= i
+ fp
->jt
+ 1;
501 /* Convert JEQ into JNE when 'jump_true' is next insn. */
502 if (fp
->jt
== 0 && BPF_OP(fp
->code
) == BPF_JEQ
) {
503 insn
->code
= BPF_JMP
| BPF_JNE
| bpf_src
;
504 target
= i
+ fp
->jf
+ 1;
509 /* Other jumps are mapped into two insns: Jxx and JA. */
510 target
= i
+ fp
->jt
+ 1;
511 insn
->code
= BPF_JMP
| BPF_OP(fp
->code
) | bpf_src
;
515 insn
->code
= BPF_JMP
| BPF_JA
;
516 target
= i
+ fp
->jf
+ 1;
520 /* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */
521 case BPF_LDX
| BPF_MSH
| BPF_B
:
523 *insn
++ = BPF_MOV64_REG(BPF_REG_TMP
, BPF_REG_A
);
524 /* A = BPF_R0 = *(u8 *) (skb->data + K) */
525 *insn
++ = BPF_LD_ABS(BPF_B
, fp
->k
);
527 *insn
++ = BPF_ALU32_IMM(BPF_AND
, BPF_REG_A
, 0xf);
529 *insn
++ = BPF_ALU32_IMM(BPF_LSH
, BPF_REG_A
, 2);
531 *insn
++ = BPF_MOV64_REG(BPF_REG_X
, BPF_REG_A
);
533 *insn
= BPF_MOV64_REG(BPF_REG_A
, BPF_REG_TMP
);
536 /* RET_K is remaped into 2 insns. RET_A case doesn't need an
537 * extra mov as BPF_REG_0 is already mapped into BPF_REG_A.
539 case BPF_RET
| BPF_A
:
540 case BPF_RET
| BPF_K
:
541 if (BPF_RVAL(fp
->code
) == BPF_K
)
542 *insn
++ = BPF_MOV32_RAW(BPF_K
, BPF_REG_0
,
544 *insn
= BPF_EXIT_INSN();
547 /* Store to stack. */
550 *insn
= BPF_STX_MEM(BPF_W
, BPF_REG_FP
, BPF_CLASS(fp
->code
) ==
551 BPF_ST
? BPF_REG_A
: BPF_REG_X
,
552 -(BPF_MEMWORDS
- fp
->k
) * 4);
555 /* Load from stack. */
556 case BPF_LD
| BPF_MEM
:
557 case BPF_LDX
| BPF_MEM
:
558 *insn
= BPF_LDX_MEM(BPF_W
, BPF_CLASS(fp
->code
) == BPF_LD
?
559 BPF_REG_A
: BPF_REG_X
, BPF_REG_FP
,
560 -(BPF_MEMWORDS
- fp
->k
) * 4);
564 case BPF_LD
| BPF_IMM
:
565 case BPF_LDX
| BPF_IMM
:
566 *insn
= BPF_MOV32_IMM(BPF_CLASS(fp
->code
) == BPF_LD
?
567 BPF_REG_A
: BPF_REG_X
, fp
->k
);
571 case BPF_MISC
| BPF_TAX
:
572 *insn
= BPF_MOV64_REG(BPF_REG_X
, BPF_REG_A
);
576 case BPF_MISC
| BPF_TXA
:
577 *insn
= BPF_MOV64_REG(BPF_REG_A
, BPF_REG_X
);
580 /* A = skb->len or X = skb->len */
581 case BPF_LD
| BPF_W
| BPF_LEN
:
582 case BPF_LDX
| BPF_W
| BPF_LEN
:
583 *insn
= BPF_LDX_MEM(BPF_W
, BPF_CLASS(fp
->code
) == BPF_LD
?
584 BPF_REG_A
: BPF_REG_X
, BPF_REG_CTX
,
585 offsetof(struct sk_buff
, len
));
588 /* Access seccomp_data fields. */
589 case BPF_LDX
| BPF_ABS
| BPF_W
:
590 /* A = *(u32 *) (ctx + K) */
591 *insn
= BPF_LDX_MEM(BPF_W
, BPF_REG_A
, BPF_REG_CTX
, fp
->k
);
594 /* Unknown instruction. */
601 memcpy(new_insn
, tmp_insns
,
602 sizeof(*insn
) * (insn
- tmp_insns
));
603 new_insn
+= insn
- tmp_insns
;
607 /* Only calculating new length. */
608 *new_len
= new_insn
- new_prog
;
613 if (new_flen
!= new_insn
- new_prog
) {
614 new_flen
= new_insn
- new_prog
;
621 BUG_ON(*new_len
!= new_flen
);
630 * As we dont want to clear mem[] array for each packet going through
631 * __bpf_prog_run(), we check that filter loaded by user never try to read
632 * a cell if not previously written, and we check all branches to be sure
633 * a malicious user doesn't try to abuse us.
635 static int check_load_and_stores(const struct sock_filter
*filter
, int flen
)
637 u16
*masks
, memvalid
= 0; /* One bit per cell, 16 cells */
640 BUILD_BUG_ON(BPF_MEMWORDS
> 16);
642 masks
= kmalloc_array(flen
, sizeof(*masks
), GFP_KERNEL
);
646 memset(masks
, 0xff, flen
* sizeof(*masks
));
648 for (pc
= 0; pc
< flen
; pc
++) {
649 memvalid
&= masks
[pc
];
651 switch (filter
[pc
].code
) {
654 memvalid
|= (1 << filter
[pc
].k
);
656 case BPF_LD
| BPF_MEM
:
657 case BPF_LDX
| BPF_MEM
:
658 if (!(memvalid
& (1 << filter
[pc
].k
))) {
663 case BPF_JMP
| BPF_JA
:
664 /* A jump must set masks on target */
665 masks
[pc
+ 1 + filter
[pc
].k
] &= memvalid
;
668 case BPF_JMP
| BPF_JEQ
| BPF_K
:
669 case BPF_JMP
| BPF_JEQ
| BPF_X
:
670 case BPF_JMP
| BPF_JGE
| BPF_K
:
671 case BPF_JMP
| BPF_JGE
| BPF_X
:
672 case BPF_JMP
| BPF_JGT
| BPF_K
:
673 case BPF_JMP
| BPF_JGT
| BPF_X
:
674 case BPF_JMP
| BPF_JSET
| BPF_K
:
675 case BPF_JMP
| BPF_JSET
| BPF_X
:
676 /* A jump must set masks on targets */
677 masks
[pc
+ 1 + filter
[pc
].jt
] &= memvalid
;
678 masks
[pc
+ 1 + filter
[pc
].jf
] &= memvalid
;
688 static bool chk_code_allowed(u16 code_to_probe
)
690 static const bool codes
[] = {
691 /* 32 bit ALU operations */
692 [BPF_ALU
| BPF_ADD
| BPF_K
] = true,
693 [BPF_ALU
| BPF_ADD
| BPF_X
] = true,
694 [BPF_ALU
| BPF_SUB
| BPF_K
] = true,
695 [BPF_ALU
| BPF_SUB
| BPF_X
] = true,
696 [BPF_ALU
| BPF_MUL
| BPF_K
] = true,
697 [BPF_ALU
| BPF_MUL
| BPF_X
] = true,
698 [BPF_ALU
| BPF_DIV
| BPF_K
] = true,
699 [BPF_ALU
| BPF_DIV
| BPF_X
] = true,
700 [BPF_ALU
| BPF_MOD
| BPF_K
] = true,
701 [BPF_ALU
| BPF_MOD
| BPF_X
] = true,
702 [BPF_ALU
| BPF_AND
| BPF_K
] = true,
703 [BPF_ALU
| BPF_AND
| BPF_X
] = true,
704 [BPF_ALU
| BPF_OR
| BPF_K
] = true,
705 [BPF_ALU
| BPF_OR
| BPF_X
] = true,
706 [BPF_ALU
| BPF_XOR
| BPF_K
] = true,
707 [BPF_ALU
| BPF_XOR
| BPF_X
] = true,
708 [BPF_ALU
| BPF_LSH
| BPF_K
] = true,
709 [BPF_ALU
| BPF_LSH
| BPF_X
] = true,
710 [BPF_ALU
| BPF_RSH
| BPF_K
] = true,
711 [BPF_ALU
| BPF_RSH
| BPF_X
] = true,
712 [BPF_ALU
| BPF_NEG
] = true,
713 /* Load instructions */
714 [BPF_LD
| BPF_W
| BPF_ABS
] = true,
715 [BPF_LD
| BPF_H
| BPF_ABS
] = true,
716 [BPF_LD
| BPF_B
| BPF_ABS
] = true,
717 [BPF_LD
| BPF_W
| BPF_LEN
] = true,
718 [BPF_LD
| BPF_W
| BPF_IND
] = true,
719 [BPF_LD
| BPF_H
| BPF_IND
] = true,
720 [BPF_LD
| BPF_B
| BPF_IND
] = true,
721 [BPF_LD
| BPF_IMM
] = true,
722 [BPF_LD
| BPF_MEM
] = true,
723 [BPF_LDX
| BPF_W
| BPF_LEN
] = true,
724 [BPF_LDX
| BPF_B
| BPF_MSH
] = true,
725 [BPF_LDX
| BPF_IMM
] = true,
726 [BPF_LDX
| BPF_MEM
] = true,
727 /* Store instructions */
730 /* Misc instructions */
731 [BPF_MISC
| BPF_TAX
] = true,
732 [BPF_MISC
| BPF_TXA
] = true,
733 /* Return instructions */
734 [BPF_RET
| BPF_K
] = true,
735 [BPF_RET
| BPF_A
] = true,
736 /* Jump instructions */
737 [BPF_JMP
| BPF_JA
] = true,
738 [BPF_JMP
| BPF_JEQ
| BPF_K
] = true,
739 [BPF_JMP
| BPF_JEQ
| BPF_X
] = true,
740 [BPF_JMP
| BPF_JGE
| BPF_K
] = true,
741 [BPF_JMP
| BPF_JGE
| BPF_X
] = true,
742 [BPF_JMP
| BPF_JGT
| BPF_K
] = true,
743 [BPF_JMP
| BPF_JGT
| BPF_X
] = true,
744 [BPF_JMP
| BPF_JSET
| BPF_K
] = true,
745 [BPF_JMP
| BPF_JSET
| BPF_X
] = true,
748 if (code_to_probe
>= ARRAY_SIZE(codes
))
751 return codes
[code_to_probe
];
754 static bool bpf_check_basics_ok(const struct sock_filter
*filter
,
759 if (flen
== 0 || flen
> BPF_MAXINSNS
)
766 * bpf_check_classic - verify socket filter code
767 * @filter: filter to verify
768 * @flen: length of filter
770 * Check the user's filter code. If we let some ugly
771 * filter code slip through kaboom! The filter must contain
772 * no references or jumps that are out of range, no illegal
773 * instructions, and must end with a RET instruction.
775 * All jumps are forward as they are not signed.
777 * Returns 0 if the rule set is legal or -EINVAL if not.
779 static int bpf_check_classic(const struct sock_filter
*filter
,
785 /* Check the filter code now */
786 for (pc
= 0; pc
< flen
; pc
++) {
787 const struct sock_filter
*ftest
= &filter
[pc
];
789 /* May we actually operate on this code? */
790 if (!chk_code_allowed(ftest
->code
))
793 /* Some instructions need special checks */
794 switch (ftest
->code
) {
795 case BPF_ALU
| BPF_DIV
| BPF_K
:
796 case BPF_ALU
| BPF_MOD
| BPF_K
:
797 /* Check for division by zero */
801 case BPF_ALU
| BPF_LSH
| BPF_K
:
802 case BPF_ALU
| BPF_RSH
| BPF_K
:
806 case BPF_LD
| BPF_MEM
:
807 case BPF_LDX
| BPF_MEM
:
810 /* Check for invalid memory addresses */
811 if (ftest
->k
>= BPF_MEMWORDS
)
814 case BPF_JMP
| BPF_JA
:
815 /* Note, the large ftest->k might cause loops.
816 * Compare this with conditional jumps below,
817 * where offsets are limited. --ANK (981016)
819 if (ftest
->k
>= (unsigned int)(flen
- pc
- 1))
822 case BPF_JMP
| BPF_JEQ
| BPF_K
:
823 case BPF_JMP
| BPF_JEQ
| BPF_X
:
824 case BPF_JMP
| BPF_JGE
| BPF_K
:
825 case BPF_JMP
| BPF_JGE
| BPF_X
:
826 case BPF_JMP
| BPF_JGT
| BPF_K
:
827 case BPF_JMP
| BPF_JGT
| BPF_X
:
828 case BPF_JMP
| BPF_JSET
| BPF_K
:
829 case BPF_JMP
| BPF_JSET
| BPF_X
:
830 /* Both conditionals must be safe */
831 if (pc
+ ftest
->jt
+ 1 >= flen
||
832 pc
+ ftest
->jf
+ 1 >= flen
)
835 case BPF_LD
| BPF_W
| BPF_ABS
:
836 case BPF_LD
| BPF_H
| BPF_ABS
:
837 case BPF_LD
| BPF_B
| BPF_ABS
:
839 if (bpf_anc_helper(ftest
) & BPF_ANC
)
841 /* Ancillary operation unknown or unsupported */
842 if (anc_found
== false && ftest
->k
>= SKF_AD_OFF
)
847 /* Last instruction must be a RET code */
848 switch (filter
[flen
- 1].code
) {
849 case BPF_RET
| BPF_K
:
850 case BPF_RET
| BPF_A
:
851 return check_load_and_stores(filter
, flen
);
857 static int bpf_prog_store_orig_filter(struct bpf_prog
*fp
,
858 const struct sock_fprog
*fprog
)
860 unsigned int fsize
= bpf_classic_proglen(fprog
);
861 struct sock_fprog_kern
*fkprog
;
863 fp
->orig_prog
= kmalloc(sizeof(*fkprog
), GFP_KERNEL
);
867 fkprog
= fp
->orig_prog
;
868 fkprog
->len
= fprog
->len
;
870 fkprog
->filter
= kmemdup(fp
->insns
, fsize
,
871 GFP_KERNEL
| __GFP_NOWARN
);
872 if (!fkprog
->filter
) {
873 kfree(fp
->orig_prog
);
880 static void bpf_release_orig_filter(struct bpf_prog
*fp
)
882 struct sock_fprog_kern
*fprog
= fp
->orig_prog
;
885 kfree(fprog
->filter
);
890 static void __bpf_prog_release(struct bpf_prog
*prog
)
892 if (prog
->type
== BPF_PROG_TYPE_SOCKET_FILTER
) {
895 bpf_release_orig_filter(prog
);
900 static void __sk_filter_release(struct sk_filter
*fp
)
902 __bpf_prog_release(fp
->prog
);
907 * sk_filter_release_rcu - Release a socket filter by rcu_head
908 * @rcu: rcu_head that contains the sk_filter to free
910 static void sk_filter_release_rcu(struct rcu_head
*rcu
)
912 struct sk_filter
*fp
= container_of(rcu
, struct sk_filter
, rcu
);
914 __sk_filter_release(fp
);
918 * sk_filter_release - release a socket filter
919 * @fp: filter to remove
921 * Remove a filter from a socket and release its resources.
923 static void sk_filter_release(struct sk_filter
*fp
)
925 if (atomic_dec_and_test(&fp
->refcnt
))
926 call_rcu(&fp
->rcu
, sk_filter_release_rcu
);
929 void sk_filter_uncharge(struct sock
*sk
, struct sk_filter
*fp
)
931 u32 filter_size
= bpf_prog_size(fp
->prog
->len
);
933 atomic_sub(filter_size
, &sk
->sk_omem_alloc
);
934 sk_filter_release(fp
);
937 /* try to charge the socket memory if there is space available
938 * return true on success
940 bool sk_filter_charge(struct sock
*sk
, struct sk_filter
*fp
)
942 u32 filter_size
= bpf_prog_size(fp
->prog
->len
);
944 /* same check as in sock_kmalloc() */
945 if (filter_size
<= sysctl_optmem_max
&&
946 atomic_read(&sk
->sk_omem_alloc
) + filter_size
< sysctl_optmem_max
) {
947 atomic_inc(&fp
->refcnt
);
948 atomic_add(filter_size
, &sk
->sk_omem_alloc
);
954 static struct bpf_prog
*bpf_migrate_filter(struct bpf_prog
*fp
)
956 struct sock_filter
*old_prog
;
957 struct bpf_prog
*old_fp
;
958 int err
, new_len
, old_len
= fp
->len
;
960 /* We are free to overwrite insns et al right here as it
961 * won't be used at this point in time anymore internally
962 * after the migration to the internal BPF instruction
965 BUILD_BUG_ON(sizeof(struct sock_filter
) !=
966 sizeof(struct bpf_insn
));
968 /* Conversion cannot happen on overlapping memory areas,
969 * so we need to keep the user BPF around until the 2nd
970 * pass. At this time, the user BPF is stored in fp->insns.
972 old_prog
= kmemdup(fp
->insns
, old_len
* sizeof(struct sock_filter
),
973 GFP_KERNEL
| __GFP_NOWARN
);
979 /* 1st pass: calculate the new program length. */
980 err
= bpf_convert_filter(old_prog
, old_len
, NULL
, &new_len
);
984 /* Expand fp for appending the new filter representation. */
986 fp
= bpf_prog_realloc(old_fp
, bpf_prog_size(new_len
), 0);
988 /* The old_fp is still around in case we couldn't
989 * allocate new memory, so uncharge on that one.
998 /* 2nd pass: remap sock_filter insns into bpf_insn insns. */
999 err
= bpf_convert_filter(old_prog
, old_len
, fp
->insnsi
, &new_len
);
1001 /* 2nd bpf_convert_filter() can fail only if it fails
1002 * to allocate memory, remapping must succeed. Note,
1003 * that at this time old_fp has already been released
1008 /* We are guaranteed to never error here with cBPF to eBPF
1009 * transitions, since there's no issue with type compatibility
1010 * checks on program arrays.
1012 fp
= bpf_prog_select_runtime(fp
, &err
);
1020 __bpf_prog_release(fp
);
1021 return ERR_PTR(err
);
1024 static struct bpf_prog
*bpf_prepare_filter(struct bpf_prog
*fp
,
1025 bpf_aux_classic_check_t trans
)
1029 fp
->bpf_func
= NULL
;
1032 err
= bpf_check_classic(fp
->insns
, fp
->len
);
1034 __bpf_prog_release(fp
);
1035 return ERR_PTR(err
);
1038 /* There might be additional checks and transformations
1039 * needed on classic filters, f.e. in case of seccomp.
1042 err
= trans(fp
->insns
, fp
->len
);
1044 __bpf_prog_release(fp
);
1045 return ERR_PTR(err
);
1049 /* Probe if we can JIT compile the filter and if so, do
1050 * the compilation of the filter.
1052 bpf_jit_compile(fp
);
1054 /* JIT compiler couldn't process this filter, so do the
1055 * internal BPF translation for the optimized interpreter.
1058 fp
= bpf_migrate_filter(fp
);
1064 * bpf_prog_create - create an unattached filter
1065 * @pfp: the unattached filter that is created
1066 * @fprog: the filter program
1068 * Create a filter independent of any socket. We first run some
1069 * sanity checks on it to make sure it does not explode on us later.
1070 * If an error occurs or there is insufficient memory for the filter
1071 * a negative errno code is returned. On success the return is zero.
1073 int bpf_prog_create(struct bpf_prog
**pfp
, struct sock_fprog_kern
*fprog
)
1075 unsigned int fsize
= bpf_classic_proglen(fprog
);
1076 struct bpf_prog
*fp
;
1078 /* Make sure new filter is there and in the right amounts. */
1079 if (!bpf_check_basics_ok(fprog
->filter
, fprog
->len
))
1082 fp
= bpf_prog_alloc(bpf_prog_size(fprog
->len
), 0);
1086 memcpy(fp
->insns
, fprog
->filter
, fsize
);
1088 fp
->len
= fprog
->len
;
1089 /* Since unattached filters are not copied back to user
1090 * space through sk_get_filter(), we do not need to hold
1091 * a copy here, and can spare us the work.
1093 fp
->orig_prog
= NULL
;
1095 /* bpf_prepare_filter() already takes care of freeing
1096 * memory in case something goes wrong.
1098 fp
= bpf_prepare_filter(fp
, NULL
);
1105 EXPORT_SYMBOL_GPL(bpf_prog_create
);
1108 * bpf_prog_create_from_user - create an unattached filter from user buffer
1109 * @pfp: the unattached filter that is created
1110 * @fprog: the filter program
1111 * @trans: post-classic verifier transformation handler
1112 * @save_orig: save classic BPF program
1114 * This function effectively does the same as bpf_prog_create(), only
1115 * that it builds up its insns buffer from user space provided buffer.
1116 * It also allows for passing a bpf_aux_classic_check_t handler.
1118 int bpf_prog_create_from_user(struct bpf_prog
**pfp
, struct sock_fprog
*fprog
,
1119 bpf_aux_classic_check_t trans
, bool save_orig
)
1121 unsigned int fsize
= bpf_classic_proglen(fprog
);
1122 struct bpf_prog
*fp
;
1125 /* Make sure new filter is there and in the right amounts. */
1126 if (!bpf_check_basics_ok(fprog
->filter
, fprog
->len
))
1129 fp
= bpf_prog_alloc(bpf_prog_size(fprog
->len
), 0);
1133 if (copy_from_user(fp
->insns
, fprog
->filter
, fsize
)) {
1134 __bpf_prog_free(fp
);
1138 fp
->len
= fprog
->len
;
1139 fp
->orig_prog
= NULL
;
1142 err
= bpf_prog_store_orig_filter(fp
, fprog
);
1144 __bpf_prog_free(fp
);
1149 /* bpf_prepare_filter() already takes care of freeing
1150 * memory in case something goes wrong.
1152 fp
= bpf_prepare_filter(fp
, trans
);
1159 EXPORT_SYMBOL_GPL(bpf_prog_create_from_user
);
1161 void bpf_prog_destroy(struct bpf_prog
*fp
)
1163 __bpf_prog_release(fp
);
1165 EXPORT_SYMBOL_GPL(bpf_prog_destroy
);
1167 static int __sk_attach_prog(struct bpf_prog
*prog
, struct sock
*sk
)
1169 struct sk_filter
*fp
, *old_fp
;
1171 fp
= kmalloc(sizeof(*fp
), GFP_KERNEL
);
1176 atomic_set(&fp
->refcnt
, 0);
1178 if (!sk_filter_charge(sk
, fp
)) {
1183 old_fp
= rcu_dereference_protected(sk
->sk_filter
,
1184 lockdep_sock_is_held(sk
));
1185 rcu_assign_pointer(sk
->sk_filter
, fp
);
1188 sk_filter_uncharge(sk
, old_fp
);
1193 static int __reuseport_attach_prog(struct bpf_prog
*prog
, struct sock
*sk
)
1195 struct bpf_prog
*old_prog
;
1198 if (bpf_prog_size(prog
->len
) > sysctl_optmem_max
)
1201 if (sk_unhashed(sk
) && sk
->sk_reuseport
) {
1202 err
= reuseport_alloc(sk
);
1205 } else if (!rcu_access_pointer(sk
->sk_reuseport_cb
)) {
1206 /* The socket wasn't bound with SO_REUSEPORT */
1210 old_prog
= reuseport_attach_prog(sk
, prog
);
1212 bpf_prog_destroy(old_prog
);
1218 struct bpf_prog
*__get_filter(struct sock_fprog
*fprog
, struct sock
*sk
)
1220 unsigned int fsize
= bpf_classic_proglen(fprog
);
1221 struct bpf_prog
*prog
;
1224 if (sock_flag(sk
, SOCK_FILTER_LOCKED
))
1225 return ERR_PTR(-EPERM
);
1227 /* Make sure new filter is there and in the right amounts. */
1228 if (!bpf_check_basics_ok(fprog
->filter
, fprog
->len
))
1229 return ERR_PTR(-EINVAL
);
1231 prog
= bpf_prog_alloc(bpf_prog_size(fprog
->len
), 0);
1233 return ERR_PTR(-ENOMEM
);
1235 if (copy_from_user(prog
->insns
, fprog
->filter
, fsize
)) {
1236 __bpf_prog_free(prog
);
1237 return ERR_PTR(-EFAULT
);
1240 prog
->len
= fprog
->len
;
1242 err
= bpf_prog_store_orig_filter(prog
, fprog
);
1244 __bpf_prog_free(prog
);
1245 return ERR_PTR(-ENOMEM
);
1248 /* bpf_prepare_filter() already takes care of freeing
1249 * memory in case something goes wrong.
1251 return bpf_prepare_filter(prog
, NULL
);
1255 * sk_attach_filter - attach a socket filter
1256 * @fprog: the filter program
1257 * @sk: the socket to use
1259 * Attach the user's filter code. We first run some sanity checks on
1260 * it to make sure it does not explode on us later. If an error
1261 * occurs or there is insufficient memory for the filter a negative
1262 * errno code is returned. On success the return is zero.
1264 int sk_attach_filter(struct sock_fprog
*fprog
, struct sock
*sk
)
1266 struct bpf_prog
*prog
= __get_filter(fprog
, sk
);
1270 return PTR_ERR(prog
);
1272 err
= __sk_attach_prog(prog
, sk
);
1274 __bpf_prog_release(prog
);
1280 EXPORT_SYMBOL_GPL(sk_attach_filter
);
1282 int sk_reuseport_attach_filter(struct sock_fprog
*fprog
, struct sock
*sk
)
1284 struct bpf_prog
*prog
= __get_filter(fprog
, sk
);
1288 return PTR_ERR(prog
);
1290 err
= __reuseport_attach_prog(prog
, sk
);
1292 __bpf_prog_release(prog
);
1299 static struct bpf_prog
*__get_bpf(u32 ufd
, struct sock
*sk
)
1301 if (sock_flag(sk
, SOCK_FILTER_LOCKED
))
1302 return ERR_PTR(-EPERM
);
1304 return bpf_prog_get_type(ufd
, BPF_PROG_TYPE_SOCKET_FILTER
);
1307 int sk_attach_bpf(u32 ufd
, struct sock
*sk
)
1309 struct bpf_prog
*prog
= __get_bpf(ufd
, sk
);
1313 return PTR_ERR(prog
);
1315 err
= __sk_attach_prog(prog
, sk
);
1324 int sk_reuseport_attach_bpf(u32 ufd
, struct sock
*sk
)
1326 struct bpf_prog
*prog
= __get_bpf(ufd
, sk
);
1330 return PTR_ERR(prog
);
1332 err
= __reuseport_attach_prog(prog
, sk
);
1341 struct bpf_scratchpad
{
1343 __be32 diff
[MAX_BPF_STACK
/ sizeof(__be32
)];
1344 u8 buff
[MAX_BPF_STACK
];
1348 static DEFINE_PER_CPU(struct bpf_scratchpad
, bpf_sp
);
1350 static inline int __bpf_try_make_writable(struct sk_buff
*skb
,
1351 unsigned int write_len
)
1353 return skb_ensure_writable(skb
, write_len
);
1356 static inline int bpf_try_make_writable(struct sk_buff
*skb
,
1357 unsigned int write_len
)
1359 int err
= __bpf_try_make_writable(skb
, write_len
);
1361 bpf_compute_data_end(skb
);
1365 static inline void bpf_push_mac_rcsum(struct sk_buff
*skb
)
1367 if (skb_at_tc_ingress(skb
))
1368 skb_postpush_rcsum(skb
, skb_mac_header(skb
), skb
->mac_len
);
1371 static inline void bpf_pull_mac_rcsum(struct sk_buff
*skb
)
1373 if (skb_at_tc_ingress(skb
))
1374 skb_postpull_rcsum(skb
, skb_mac_header(skb
), skb
->mac_len
);
1377 BPF_CALL_5(bpf_skb_store_bytes
, struct sk_buff
*, skb
, u32
, offset
,
1378 const void *, from
, u32
, len
, u64
, flags
)
1382 if (unlikely(flags
& ~(BPF_F_RECOMPUTE_CSUM
| BPF_F_INVALIDATE_HASH
)))
1384 if (unlikely(offset
> 0xffff))
1386 if (unlikely(bpf_try_make_writable(skb
, offset
+ len
)))
1389 ptr
= skb
->data
+ offset
;
1390 if (flags
& BPF_F_RECOMPUTE_CSUM
)
1391 __skb_postpull_rcsum(skb
, ptr
, len
, offset
);
1393 memcpy(ptr
, from
, len
);
1395 if (flags
& BPF_F_RECOMPUTE_CSUM
)
1396 __skb_postpush_rcsum(skb
, ptr
, len
, offset
);
1397 if (flags
& BPF_F_INVALIDATE_HASH
)
1398 skb_clear_hash(skb
);
1403 static const struct bpf_func_proto bpf_skb_store_bytes_proto
= {
1404 .func
= bpf_skb_store_bytes
,
1406 .ret_type
= RET_INTEGER
,
1407 .arg1_type
= ARG_PTR_TO_CTX
,
1408 .arg2_type
= ARG_ANYTHING
,
1409 .arg3_type
= ARG_PTR_TO_STACK
,
1410 .arg4_type
= ARG_CONST_STACK_SIZE
,
1411 .arg5_type
= ARG_ANYTHING
,
1414 BPF_CALL_4(bpf_skb_load_bytes
, const struct sk_buff
*, skb
, u32
, offset
,
1415 void *, to
, u32
, len
)
1419 if (unlikely(offset
> 0xffff))
1422 ptr
= skb_header_pointer(skb
, offset
, len
, to
);
1426 memcpy(to
, ptr
, len
);
1434 static const struct bpf_func_proto bpf_skb_load_bytes_proto
= {
1435 .func
= bpf_skb_load_bytes
,
1437 .ret_type
= RET_INTEGER
,
1438 .arg1_type
= ARG_PTR_TO_CTX
,
1439 .arg2_type
= ARG_ANYTHING
,
1440 .arg3_type
= ARG_PTR_TO_RAW_STACK
,
1441 .arg4_type
= ARG_CONST_STACK_SIZE
,
1444 BPF_CALL_5(bpf_l3_csum_replace
, struct sk_buff
*, skb
, u32
, offset
,
1445 u64
, from
, u64
, to
, u64
, flags
)
1449 if (unlikely(flags
& ~(BPF_F_HDR_FIELD_MASK
)))
1451 if (unlikely(offset
> 0xffff || offset
& 1))
1453 if (unlikely(bpf_try_make_writable(skb
, offset
+ sizeof(*ptr
))))
1456 ptr
= (__sum16
*)(skb
->data
+ offset
);
1457 switch (flags
& BPF_F_HDR_FIELD_MASK
) {
1459 if (unlikely(from
!= 0))
1462 csum_replace_by_diff(ptr
, to
);
1465 csum_replace2(ptr
, from
, to
);
1468 csum_replace4(ptr
, from
, to
);
1477 static const struct bpf_func_proto bpf_l3_csum_replace_proto
= {
1478 .func
= bpf_l3_csum_replace
,
1480 .ret_type
= RET_INTEGER
,
1481 .arg1_type
= ARG_PTR_TO_CTX
,
1482 .arg2_type
= ARG_ANYTHING
,
1483 .arg3_type
= ARG_ANYTHING
,
1484 .arg4_type
= ARG_ANYTHING
,
1485 .arg5_type
= ARG_ANYTHING
,
1488 BPF_CALL_5(bpf_l4_csum_replace
, struct sk_buff
*, skb
, u32
, offset
,
1489 u64
, from
, u64
, to
, u64
, flags
)
1491 bool is_pseudo
= flags
& BPF_F_PSEUDO_HDR
;
1492 bool is_mmzero
= flags
& BPF_F_MARK_MANGLED_0
;
1495 if (unlikely(flags
& ~(BPF_F_MARK_MANGLED_0
| BPF_F_PSEUDO_HDR
|
1496 BPF_F_HDR_FIELD_MASK
)))
1498 if (unlikely(offset
> 0xffff || offset
& 1))
1500 if (unlikely(bpf_try_make_writable(skb
, offset
+ sizeof(*ptr
))))
1503 ptr
= (__sum16
*)(skb
->data
+ offset
);
1504 if (is_mmzero
&& !*ptr
)
1507 switch (flags
& BPF_F_HDR_FIELD_MASK
) {
1509 if (unlikely(from
!= 0))
1512 inet_proto_csum_replace_by_diff(ptr
, skb
, to
, is_pseudo
);
1515 inet_proto_csum_replace2(ptr
, skb
, from
, to
, is_pseudo
);
1518 inet_proto_csum_replace4(ptr
, skb
, from
, to
, is_pseudo
);
1524 if (is_mmzero
&& !*ptr
)
1525 *ptr
= CSUM_MANGLED_0
;
1529 static const struct bpf_func_proto bpf_l4_csum_replace_proto
= {
1530 .func
= bpf_l4_csum_replace
,
1532 .ret_type
= RET_INTEGER
,
1533 .arg1_type
= ARG_PTR_TO_CTX
,
1534 .arg2_type
= ARG_ANYTHING
,
1535 .arg3_type
= ARG_ANYTHING
,
1536 .arg4_type
= ARG_ANYTHING
,
1537 .arg5_type
= ARG_ANYTHING
,
1540 BPF_CALL_5(bpf_csum_diff
, __be32
*, from
, u32
, from_size
,
1541 __be32
*, to
, u32
, to_size
, __wsum
, seed
)
1543 struct bpf_scratchpad
*sp
= this_cpu_ptr(&bpf_sp
);
1544 u32 diff_size
= from_size
+ to_size
;
1547 /* This is quite flexible, some examples:
1549 * from_size == 0, to_size > 0, seed := csum --> pushing data
1550 * from_size > 0, to_size == 0, seed := csum --> pulling data
1551 * from_size > 0, to_size > 0, seed := 0 --> diffing data
1553 * Even for diffing, from_size and to_size don't need to be equal.
1555 if (unlikely(((from_size
| to_size
) & (sizeof(__be32
) - 1)) ||
1556 diff_size
> sizeof(sp
->diff
)))
1559 for (i
= 0; i
< from_size
/ sizeof(__be32
); i
++, j
++)
1560 sp
->diff
[j
] = ~from
[i
];
1561 for (i
= 0; i
< to_size
/ sizeof(__be32
); i
++, j
++)
1562 sp
->diff
[j
] = to
[i
];
1564 return csum_partial(sp
->diff
, diff_size
, seed
);
1567 static const struct bpf_func_proto bpf_csum_diff_proto
= {
1568 .func
= bpf_csum_diff
,
1570 .ret_type
= RET_INTEGER
,
1571 .arg1_type
= ARG_PTR_TO_STACK
,
1572 .arg2_type
= ARG_CONST_STACK_SIZE_OR_ZERO
,
1573 .arg3_type
= ARG_PTR_TO_STACK
,
1574 .arg4_type
= ARG_CONST_STACK_SIZE_OR_ZERO
,
1575 .arg5_type
= ARG_ANYTHING
,
1578 static inline int __bpf_rx_skb(struct net_device
*dev
, struct sk_buff
*skb
)
1580 return dev_forward_skb(dev
, skb
);
1583 static inline int __bpf_tx_skb(struct net_device
*dev
, struct sk_buff
*skb
)
1587 if (unlikely(__this_cpu_read(xmit_recursion
) > XMIT_RECURSION_LIMIT
)) {
1588 net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
1595 __this_cpu_inc(xmit_recursion
);
1596 ret
= dev_queue_xmit(skb
);
1597 __this_cpu_dec(xmit_recursion
);
1602 BPF_CALL_3(bpf_clone_redirect
, struct sk_buff
*, skb
, u32
, ifindex
, u64
, flags
)
1604 struct net_device
*dev
;
1606 if (unlikely(flags
& ~(BPF_F_INGRESS
)))
1609 dev
= dev_get_by_index_rcu(dev_net(skb
->dev
), ifindex
);
1613 skb
= skb_clone(skb
, GFP_ATOMIC
);
1617 bpf_push_mac_rcsum(skb
);
1619 return flags
& BPF_F_INGRESS
?
1620 __bpf_rx_skb(dev
, skb
) : __bpf_tx_skb(dev
, skb
);
1623 static const struct bpf_func_proto bpf_clone_redirect_proto
= {
1624 .func
= bpf_clone_redirect
,
1626 .ret_type
= RET_INTEGER
,
1627 .arg1_type
= ARG_PTR_TO_CTX
,
1628 .arg2_type
= ARG_ANYTHING
,
1629 .arg3_type
= ARG_ANYTHING
,
1632 struct redirect_info
{
1637 static DEFINE_PER_CPU(struct redirect_info
, redirect_info
);
1639 BPF_CALL_2(bpf_redirect
, u32
, ifindex
, u64
, flags
)
1641 struct redirect_info
*ri
= this_cpu_ptr(&redirect_info
);
1643 if (unlikely(flags
& ~(BPF_F_INGRESS
)))
1646 ri
->ifindex
= ifindex
;
1649 return TC_ACT_REDIRECT
;
1652 int skb_do_redirect(struct sk_buff
*skb
)
1654 struct redirect_info
*ri
= this_cpu_ptr(&redirect_info
);
1655 struct net_device
*dev
;
1657 dev
= dev_get_by_index_rcu(dev_net(skb
->dev
), ri
->ifindex
);
1659 if (unlikely(!dev
)) {
1664 bpf_push_mac_rcsum(skb
);
1666 return ri
->flags
& BPF_F_INGRESS
?
1667 __bpf_rx_skb(dev
, skb
) : __bpf_tx_skb(dev
, skb
);
1670 static const struct bpf_func_proto bpf_redirect_proto
= {
1671 .func
= bpf_redirect
,
1673 .ret_type
= RET_INTEGER
,
1674 .arg1_type
= ARG_ANYTHING
,
1675 .arg2_type
= ARG_ANYTHING
,
1678 BPF_CALL_1(bpf_get_cgroup_classid
, const struct sk_buff
*, skb
)
1680 return task_get_classid(skb
);
1683 static const struct bpf_func_proto bpf_get_cgroup_classid_proto
= {
1684 .func
= bpf_get_cgroup_classid
,
1686 .ret_type
= RET_INTEGER
,
1687 .arg1_type
= ARG_PTR_TO_CTX
,
1690 BPF_CALL_1(bpf_get_route_realm
, const struct sk_buff
*, skb
)
1692 return dst_tclassid(skb
);
1695 static const struct bpf_func_proto bpf_get_route_realm_proto
= {
1696 .func
= bpf_get_route_realm
,
1698 .ret_type
= RET_INTEGER
,
1699 .arg1_type
= ARG_PTR_TO_CTX
,
1702 BPF_CALL_1(bpf_get_hash_recalc
, struct sk_buff
*, skb
)
1704 /* If skb_clear_hash() was called due to mangling, we can
1705 * trigger SW recalculation here. Later access to hash
1706 * can then use the inline skb->hash via context directly
1707 * instead of calling this helper again.
1709 return skb_get_hash(skb
);
1712 static const struct bpf_func_proto bpf_get_hash_recalc_proto
= {
1713 .func
= bpf_get_hash_recalc
,
1715 .ret_type
= RET_INTEGER
,
1716 .arg1_type
= ARG_PTR_TO_CTX
,
1719 BPF_CALL_3(bpf_skb_vlan_push
, struct sk_buff
*, skb
, __be16
, vlan_proto
,
1724 if (unlikely(vlan_proto
!= htons(ETH_P_8021Q
) &&
1725 vlan_proto
!= htons(ETH_P_8021AD
)))
1726 vlan_proto
= htons(ETH_P_8021Q
);
1728 bpf_push_mac_rcsum(skb
);
1729 ret
= skb_vlan_push(skb
, vlan_proto
, vlan_tci
);
1730 bpf_pull_mac_rcsum(skb
);
1732 bpf_compute_data_end(skb
);
1736 const struct bpf_func_proto bpf_skb_vlan_push_proto
= {
1737 .func
= bpf_skb_vlan_push
,
1739 .ret_type
= RET_INTEGER
,
1740 .arg1_type
= ARG_PTR_TO_CTX
,
1741 .arg2_type
= ARG_ANYTHING
,
1742 .arg3_type
= ARG_ANYTHING
,
1744 EXPORT_SYMBOL_GPL(bpf_skb_vlan_push_proto
);
1746 BPF_CALL_1(bpf_skb_vlan_pop
, struct sk_buff
*, skb
)
1750 bpf_push_mac_rcsum(skb
);
1751 ret
= skb_vlan_pop(skb
);
1752 bpf_pull_mac_rcsum(skb
);
1754 bpf_compute_data_end(skb
);
1758 const struct bpf_func_proto bpf_skb_vlan_pop_proto
= {
1759 .func
= bpf_skb_vlan_pop
,
1761 .ret_type
= RET_INTEGER
,
1762 .arg1_type
= ARG_PTR_TO_CTX
,
1764 EXPORT_SYMBOL_GPL(bpf_skb_vlan_pop_proto
);
1766 static int bpf_skb_generic_push(struct sk_buff
*skb
, u32 off
, u32 len
)
1768 /* Caller already did skb_cow() with len as headroom,
1769 * so no need to do it here.
1772 memmove(skb
->data
, skb
->data
+ len
, off
);
1773 memset(skb
->data
+ off
, 0, len
);
1775 /* No skb_postpush_rcsum(skb, skb->data + off, len)
1776 * needed here as it does not change the skb->csum
1777 * result for checksum complete when summing over
1783 static int bpf_skb_generic_pop(struct sk_buff
*skb
, u32 off
, u32 len
)
1785 /* skb_ensure_writable() is not needed here, as we're
1786 * already working on an uncloned skb.
1788 if (unlikely(!pskb_may_pull(skb
, off
+ len
)))
1791 skb_postpull_rcsum(skb
, skb
->data
+ off
, len
);
1792 memmove(skb
->data
+ len
, skb
->data
, off
);
1793 __skb_pull(skb
, len
);
1798 static int bpf_skb_net_hdr_push(struct sk_buff
*skb
, u32 off
, u32 len
)
1800 bool trans_same
= skb
->transport_header
== skb
->network_header
;
1803 /* There's no need for __skb_push()/__skb_pull() pair to
1804 * get to the start of the mac header as we're guaranteed
1805 * to always start from here under eBPF.
1807 ret
= bpf_skb_generic_push(skb
, off
, len
);
1809 skb
->mac_header
-= len
;
1810 skb
->network_header
-= len
;
1812 skb
->transport_header
= skb
->network_header
;
1818 static int bpf_skb_net_hdr_pop(struct sk_buff
*skb
, u32 off
, u32 len
)
1820 bool trans_same
= skb
->transport_header
== skb
->network_header
;
1823 /* Same here, __skb_push()/__skb_pull() pair not needed. */
1824 ret
= bpf_skb_generic_pop(skb
, off
, len
);
1826 skb
->mac_header
+= len
;
1827 skb
->network_header
+= len
;
1829 skb
->transport_header
= skb
->network_header
;
1835 static int bpf_skb_proto_4_to_6(struct sk_buff
*skb
)
1837 const u32 len_diff
= sizeof(struct ipv6hdr
) - sizeof(struct iphdr
);
1838 u32 off
= skb
->network_header
- skb
->mac_header
;
1841 ret
= skb_cow(skb
, len_diff
);
1842 if (unlikely(ret
< 0))
1845 ret
= bpf_skb_net_hdr_push(skb
, off
, len_diff
);
1846 if (unlikely(ret
< 0))
1849 if (skb_is_gso(skb
)) {
1850 /* SKB_GSO_UDP stays as is. SKB_GSO_TCPV4 needs to
1851 * be changed into SKB_GSO_TCPV6.
1853 if (skb_shinfo(skb
)->gso_type
& SKB_GSO_TCPV4
) {
1854 skb_shinfo(skb
)->gso_type
&= ~SKB_GSO_TCPV4
;
1855 skb_shinfo(skb
)->gso_type
|= SKB_GSO_TCPV6
;
1858 /* Due to IPv6 header, MSS needs to be downgraded. */
1859 skb_shinfo(skb
)->gso_size
-= len_diff
;
1860 /* Header must be checked, and gso_segs recomputed. */
1861 skb_shinfo(skb
)->gso_type
|= SKB_GSO_DODGY
;
1862 skb_shinfo(skb
)->gso_segs
= 0;
1865 skb
->protocol
= htons(ETH_P_IPV6
);
1866 skb_clear_hash(skb
);
1871 static int bpf_skb_proto_6_to_4(struct sk_buff
*skb
)
1873 const u32 len_diff
= sizeof(struct ipv6hdr
) - sizeof(struct iphdr
);
1874 u32 off
= skb
->network_header
- skb
->mac_header
;
1877 ret
= skb_unclone(skb
, GFP_ATOMIC
);
1878 if (unlikely(ret
< 0))
1881 ret
= bpf_skb_net_hdr_pop(skb
, off
, len_diff
);
1882 if (unlikely(ret
< 0))
1885 if (skb_is_gso(skb
)) {
1886 /* SKB_GSO_UDP stays as is. SKB_GSO_TCPV6 needs to
1887 * be changed into SKB_GSO_TCPV4.
1889 if (skb_shinfo(skb
)->gso_type
& SKB_GSO_TCPV6
) {
1890 skb_shinfo(skb
)->gso_type
&= ~SKB_GSO_TCPV6
;
1891 skb_shinfo(skb
)->gso_type
|= SKB_GSO_TCPV4
;
1894 /* Due to IPv4 header, MSS can be upgraded. */
1895 skb_shinfo(skb
)->gso_size
+= len_diff
;
1896 /* Header must be checked, and gso_segs recomputed. */
1897 skb_shinfo(skb
)->gso_type
|= SKB_GSO_DODGY
;
1898 skb_shinfo(skb
)->gso_segs
= 0;
1901 skb
->protocol
= htons(ETH_P_IP
);
1902 skb_clear_hash(skb
);
1907 static int bpf_skb_proto_xlat(struct sk_buff
*skb
, __be16 to_proto
)
1909 __be16 from_proto
= skb
->protocol
;
1911 if (from_proto
== htons(ETH_P_IP
) &&
1912 to_proto
== htons(ETH_P_IPV6
))
1913 return bpf_skb_proto_4_to_6(skb
);
1915 if (from_proto
== htons(ETH_P_IPV6
) &&
1916 to_proto
== htons(ETH_P_IP
))
1917 return bpf_skb_proto_6_to_4(skb
);
1922 BPF_CALL_3(bpf_skb_change_proto
, struct sk_buff
*, skb
, __be16
, proto
,
1927 if (unlikely(flags
))
1930 /* General idea is that this helper does the basic groundwork
1931 * needed for changing the protocol, and eBPF program fills the
1932 * rest through bpf_skb_store_bytes(), bpf_lX_csum_replace()
1933 * and other helpers, rather than passing a raw buffer here.
1935 * The rationale is to keep this minimal and without a need to
1936 * deal with raw packet data. F.e. even if we would pass buffers
1937 * here, the program still needs to call the bpf_lX_csum_replace()
1938 * helpers anyway. Plus, this way we keep also separation of
1939 * concerns, since f.e. bpf_skb_store_bytes() should only take
1942 * Currently, additional options and extension header space are
1943 * not supported, but flags register is reserved so we can adapt
1944 * that. For offloads, we mark packet as dodgy, so that headers
1945 * need to be verified first.
1947 ret
= bpf_skb_proto_xlat(skb
, proto
);
1948 bpf_compute_data_end(skb
);
1952 static const struct bpf_func_proto bpf_skb_change_proto_proto
= {
1953 .func
= bpf_skb_change_proto
,
1955 .ret_type
= RET_INTEGER
,
1956 .arg1_type
= ARG_PTR_TO_CTX
,
1957 .arg2_type
= ARG_ANYTHING
,
1958 .arg3_type
= ARG_ANYTHING
,
1961 BPF_CALL_2(bpf_skb_change_type
, struct sk_buff
*, skb
, u32
, pkt_type
)
1963 /* We only allow a restricted subset to be changed for now. */
1964 if (unlikely(!skb_pkt_type_ok(skb
->pkt_type
) ||
1965 !skb_pkt_type_ok(pkt_type
)))
1968 skb
->pkt_type
= pkt_type
;
1972 static const struct bpf_func_proto bpf_skb_change_type_proto
= {
1973 .func
= bpf_skb_change_type
,
1975 .ret_type
= RET_INTEGER
,
1976 .arg1_type
= ARG_PTR_TO_CTX
,
1977 .arg2_type
= ARG_ANYTHING
,
1980 static u32
__bpf_skb_min_len(const struct sk_buff
*skb
)
1982 u32 min_len
= skb_network_offset(skb
);
1984 if (skb_transport_header_was_set(skb
))
1985 min_len
= skb_transport_offset(skb
);
1986 if (skb
->ip_summed
== CHECKSUM_PARTIAL
)
1987 min_len
= skb_checksum_start_offset(skb
) +
1988 skb
->csum_offset
+ sizeof(__sum16
);
1992 static u32
__bpf_skb_max_len(const struct sk_buff
*skb
)
1994 return skb
->dev
->mtu
+ skb
->dev
->hard_header_len
;
1997 static int bpf_skb_grow_rcsum(struct sk_buff
*skb
, unsigned int new_len
)
1999 unsigned int old_len
= skb
->len
;
2002 ret
= __skb_grow_rcsum(skb
, new_len
);
2004 memset(skb
->data
+ old_len
, 0, new_len
- old_len
);
2008 static int bpf_skb_trim_rcsum(struct sk_buff
*skb
, unsigned int new_len
)
2010 return __skb_trim_rcsum(skb
, new_len
);
2013 BPF_CALL_3(bpf_skb_change_tail
, struct sk_buff
*, skb
, u32
, new_len
,
2016 u32 max_len
= __bpf_skb_max_len(skb
);
2017 u32 min_len
= __bpf_skb_min_len(skb
);
2020 if (unlikely(flags
|| new_len
> max_len
|| new_len
< min_len
))
2022 if (skb
->encapsulation
)
2025 /* The basic idea of this helper is that it's performing the
2026 * needed work to either grow or trim an skb, and eBPF program
2027 * rewrites the rest via helpers like bpf_skb_store_bytes(),
2028 * bpf_lX_csum_replace() and others rather than passing a raw
2029 * buffer here. This one is a slow path helper and intended
2030 * for replies with control messages.
2032 * Like in bpf_skb_change_proto(), we want to keep this rather
2033 * minimal and without protocol specifics so that we are able
2034 * to separate concerns as in bpf_skb_store_bytes() should only
2035 * be the one responsible for writing buffers.
2037 * It's really expected to be a slow path operation here for
2038 * control message replies, so we're implicitly linearizing,
2039 * uncloning and drop offloads from the skb by this.
2041 ret
= __bpf_try_make_writable(skb
, skb
->len
);
2043 if (new_len
> skb
->len
)
2044 ret
= bpf_skb_grow_rcsum(skb
, new_len
);
2045 else if (new_len
< skb
->len
)
2046 ret
= bpf_skb_trim_rcsum(skb
, new_len
);
2047 if (!ret
&& skb_is_gso(skb
))
2051 bpf_compute_data_end(skb
);
2055 static const struct bpf_func_proto bpf_skb_change_tail_proto
= {
2056 .func
= bpf_skb_change_tail
,
2058 .ret_type
= RET_INTEGER
,
2059 .arg1_type
= ARG_PTR_TO_CTX
,
2060 .arg2_type
= ARG_ANYTHING
,
2061 .arg3_type
= ARG_ANYTHING
,
2064 bool bpf_helper_changes_skb_data(void *func
)
2066 if (func
== bpf_skb_vlan_push
)
2068 if (func
== bpf_skb_vlan_pop
)
2070 if (func
== bpf_skb_store_bytes
)
2072 if (func
== bpf_skb_change_proto
)
2074 if (func
== bpf_skb_change_tail
)
2076 if (func
== bpf_l3_csum_replace
)
2078 if (func
== bpf_l4_csum_replace
)
2084 static unsigned long bpf_skb_copy(void *dst_buff
, const void *skb
,
2085 unsigned long off
, unsigned long len
)
2087 void *ptr
= skb_header_pointer(skb
, off
, len
, dst_buff
);
2091 if (ptr
!= dst_buff
)
2092 memcpy(dst_buff
, ptr
, len
);
2097 BPF_CALL_5(bpf_skb_event_output
, struct sk_buff
*, skb
, struct bpf_map
*, map
,
2098 u64
, flags
, void *, meta
, u64
, meta_size
)
2100 u64 skb_size
= (flags
& BPF_F_CTXLEN_MASK
) >> 32;
2102 if (unlikely(flags
& ~(BPF_F_CTXLEN_MASK
| BPF_F_INDEX_MASK
)))
2104 if (unlikely(skb_size
> skb
->len
))
2107 return bpf_event_output(map
, flags
, meta
, meta_size
, skb
, skb_size
,
2111 static const struct bpf_func_proto bpf_skb_event_output_proto
= {
2112 .func
= bpf_skb_event_output
,
2114 .ret_type
= RET_INTEGER
,
2115 .arg1_type
= ARG_PTR_TO_CTX
,
2116 .arg2_type
= ARG_CONST_MAP_PTR
,
2117 .arg3_type
= ARG_ANYTHING
,
2118 .arg4_type
= ARG_PTR_TO_STACK
,
2119 .arg5_type
= ARG_CONST_STACK_SIZE
,
2122 static unsigned short bpf_tunnel_key_af(u64 flags
)
2124 return flags
& BPF_F_TUNINFO_IPV6
? AF_INET6
: AF_INET
;
2127 BPF_CALL_4(bpf_skb_get_tunnel_key
, struct sk_buff
*, skb
, struct bpf_tunnel_key
*, to
,
2128 u32
, size
, u64
, flags
)
2130 const struct ip_tunnel_info
*info
= skb_tunnel_info(skb
);
2131 u8 compat
[sizeof(struct bpf_tunnel_key
)];
2135 if (unlikely(!info
|| (flags
& ~(BPF_F_TUNINFO_IPV6
)))) {
2139 if (ip_tunnel_info_af(info
) != bpf_tunnel_key_af(flags
)) {
2143 if (unlikely(size
!= sizeof(struct bpf_tunnel_key
))) {
2146 case offsetof(struct bpf_tunnel_key
, tunnel_label
):
2147 case offsetof(struct bpf_tunnel_key
, tunnel_ext
):
2149 case offsetof(struct bpf_tunnel_key
, remote_ipv6
[1]):
2150 /* Fixup deprecated structure layouts here, so we have
2151 * a common path later on.
2153 if (ip_tunnel_info_af(info
) != AF_INET
)
2156 to
= (struct bpf_tunnel_key
*)compat
;
2163 to
->tunnel_id
= be64_to_cpu(info
->key
.tun_id
);
2164 to
->tunnel_tos
= info
->key
.tos
;
2165 to
->tunnel_ttl
= info
->key
.ttl
;
2167 if (flags
& BPF_F_TUNINFO_IPV6
) {
2168 memcpy(to
->remote_ipv6
, &info
->key
.u
.ipv6
.src
,
2169 sizeof(to
->remote_ipv6
));
2170 to
->tunnel_label
= be32_to_cpu(info
->key
.label
);
2172 to
->remote_ipv4
= be32_to_cpu(info
->key
.u
.ipv4
.src
);
2175 if (unlikely(size
!= sizeof(struct bpf_tunnel_key
)))
2176 memcpy(to_orig
, to
, size
);
2180 memset(to_orig
, 0, size
);
2184 static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto
= {
2185 .func
= bpf_skb_get_tunnel_key
,
2187 .ret_type
= RET_INTEGER
,
2188 .arg1_type
= ARG_PTR_TO_CTX
,
2189 .arg2_type
= ARG_PTR_TO_RAW_STACK
,
2190 .arg3_type
= ARG_CONST_STACK_SIZE
,
2191 .arg4_type
= ARG_ANYTHING
,
2194 BPF_CALL_3(bpf_skb_get_tunnel_opt
, struct sk_buff
*, skb
, u8
*, to
, u32
, size
)
2196 const struct ip_tunnel_info
*info
= skb_tunnel_info(skb
);
2199 if (unlikely(!info
||
2200 !(info
->key
.tun_flags
& TUNNEL_OPTIONS_PRESENT
))) {
2204 if (unlikely(size
< info
->options_len
)) {
2209 ip_tunnel_info_opts_get(to
, info
);
2210 if (size
> info
->options_len
)
2211 memset(to
+ info
->options_len
, 0, size
- info
->options_len
);
2213 return info
->options_len
;
2215 memset(to
, 0, size
);
2219 static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto
= {
2220 .func
= bpf_skb_get_tunnel_opt
,
2222 .ret_type
= RET_INTEGER
,
2223 .arg1_type
= ARG_PTR_TO_CTX
,
2224 .arg2_type
= ARG_PTR_TO_RAW_STACK
,
2225 .arg3_type
= ARG_CONST_STACK_SIZE
,
2228 static struct metadata_dst __percpu
*md_dst
;
2230 BPF_CALL_4(bpf_skb_set_tunnel_key
, struct sk_buff
*, skb
,
2231 const struct bpf_tunnel_key
*, from
, u32
, size
, u64
, flags
)
2233 struct metadata_dst
*md
= this_cpu_ptr(md_dst
);
2234 u8 compat
[sizeof(struct bpf_tunnel_key
)];
2235 struct ip_tunnel_info
*info
;
2237 if (unlikely(flags
& ~(BPF_F_TUNINFO_IPV6
| BPF_F_ZERO_CSUM_TX
|
2238 BPF_F_DONT_FRAGMENT
)))
2240 if (unlikely(size
!= sizeof(struct bpf_tunnel_key
))) {
2242 case offsetof(struct bpf_tunnel_key
, tunnel_label
):
2243 case offsetof(struct bpf_tunnel_key
, tunnel_ext
):
2244 case offsetof(struct bpf_tunnel_key
, remote_ipv6
[1]):
2245 /* Fixup deprecated structure layouts here, so we have
2246 * a common path later on.
2248 memcpy(compat
, from
, size
);
2249 memset(compat
+ size
, 0, sizeof(compat
) - size
);
2250 from
= (const struct bpf_tunnel_key
*) compat
;
2256 if (unlikely((!(flags
& BPF_F_TUNINFO_IPV6
) && from
->tunnel_label
) ||
2261 dst_hold((struct dst_entry
*) md
);
2262 skb_dst_set(skb
, (struct dst_entry
*) md
);
2264 info
= &md
->u
.tun_info
;
2265 info
->mode
= IP_TUNNEL_INFO_TX
;
2267 info
->key
.tun_flags
= TUNNEL_KEY
| TUNNEL_CSUM
| TUNNEL_NOCACHE
;
2268 if (flags
& BPF_F_DONT_FRAGMENT
)
2269 info
->key
.tun_flags
|= TUNNEL_DONT_FRAGMENT
;
2271 info
->key
.tun_id
= cpu_to_be64(from
->tunnel_id
);
2272 info
->key
.tos
= from
->tunnel_tos
;
2273 info
->key
.ttl
= from
->tunnel_ttl
;
2275 if (flags
& BPF_F_TUNINFO_IPV6
) {
2276 info
->mode
|= IP_TUNNEL_INFO_IPV6
;
2277 memcpy(&info
->key
.u
.ipv6
.dst
, from
->remote_ipv6
,
2278 sizeof(from
->remote_ipv6
));
2279 info
->key
.label
= cpu_to_be32(from
->tunnel_label
) &
2280 IPV6_FLOWLABEL_MASK
;
2282 info
->key
.u
.ipv4
.dst
= cpu_to_be32(from
->remote_ipv4
);
2283 if (flags
& BPF_F_ZERO_CSUM_TX
)
2284 info
->key
.tun_flags
&= ~TUNNEL_CSUM
;
2290 static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto
= {
2291 .func
= bpf_skb_set_tunnel_key
,
2293 .ret_type
= RET_INTEGER
,
2294 .arg1_type
= ARG_PTR_TO_CTX
,
2295 .arg2_type
= ARG_PTR_TO_STACK
,
2296 .arg3_type
= ARG_CONST_STACK_SIZE
,
2297 .arg4_type
= ARG_ANYTHING
,
2300 BPF_CALL_3(bpf_skb_set_tunnel_opt
, struct sk_buff
*, skb
,
2301 const u8
*, from
, u32
, size
)
2303 struct ip_tunnel_info
*info
= skb_tunnel_info(skb
);
2304 const struct metadata_dst
*md
= this_cpu_ptr(md_dst
);
2306 if (unlikely(info
!= &md
->u
.tun_info
|| (size
& (sizeof(u32
) - 1))))
2308 if (unlikely(size
> IP_TUNNEL_OPTS_MAX
))
2311 ip_tunnel_info_opts_set(info
, from
, size
);
2316 static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto
= {
2317 .func
= bpf_skb_set_tunnel_opt
,
2319 .ret_type
= RET_INTEGER
,
2320 .arg1_type
= ARG_PTR_TO_CTX
,
2321 .arg2_type
= ARG_PTR_TO_STACK
,
2322 .arg3_type
= ARG_CONST_STACK_SIZE
,
2325 static const struct bpf_func_proto
*
2326 bpf_get_skb_set_tunnel_proto(enum bpf_func_id which
)
2329 /* Race is not possible, since it's called from verifier
2330 * that is holding verifier mutex.
2332 md_dst
= metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX
,
2339 case BPF_FUNC_skb_set_tunnel_key
:
2340 return &bpf_skb_set_tunnel_key_proto
;
2341 case BPF_FUNC_skb_set_tunnel_opt
:
2342 return &bpf_skb_set_tunnel_opt_proto
;
2348 BPF_CALL_3(bpf_skb_under_cgroup
, struct sk_buff
*, skb
, struct bpf_map
*, map
,
2351 struct bpf_array
*array
= container_of(map
, struct bpf_array
, map
);
2352 struct cgroup
*cgrp
;
2356 if (!sk
|| !sk_fullsock(sk
))
2358 if (unlikely(idx
>= array
->map
.max_entries
))
2361 cgrp
= READ_ONCE(array
->ptrs
[idx
]);
2362 if (unlikely(!cgrp
))
2365 return sk_under_cgroup_hierarchy(sk
, cgrp
);
2368 static const struct bpf_func_proto bpf_skb_under_cgroup_proto
= {
2369 .func
= bpf_skb_under_cgroup
,
2371 .ret_type
= RET_INTEGER
,
2372 .arg1_type
= ARG_PTR_TO_CTX
,
2373 .arg2_type
= ARG_CONST_MAP_PTR
,
2374 .arg3_type
= ARG_ANYTHING
,
2377 static unsigned long bpf_xdp_copy(void *dst_buff
, const void *src_buff
,
2378 unsigned long off
, unsigned long len
)
2380 memcpy(dst_buff
, src_buff
+ off
, len
);
2384 BPF_CALL_5(bpf_xdp_event_output
, struct xdp_buff
*, xdp
, struct bpf_map
*, map
,
2385 u64
, flags
, void *, meta
, u64
, meta_size
)
2387 u64 xdp_size
= (flags
& BPF_F_CTXLEN_MASK
) >> 32;
2389 if (unlikely(flags
& ~(BPF_F_CTXLEN_MASK
| BPF_F_INDEX_MASK
)))
2391 if (unlikely(xdp_size
> (unsigned long)(xdp
->data_end
- xdp
->data
)))
2394 return bpf_event_output(map
, flags
, meta
, meta_size
, xdp
, xdp_size
,
2398 static const struct bpf_func_proto bpf_xdp_event_output_proto
= {
2399 .func
= bpf_xdp_event_output
,
2401 .ret_type
= RET_INTEGER
,
2402 .arg1_type
= ARG_PTR_TO_CTX
,
2403 .arg2_type
= ARG_CONST_MAP_PTR
,
2404 .arg3_type
= ARG_ANYTHING
,
2405 .arg4_type
= ARG_PTR_TO_STACK
,
2406 .arg5_type
= ARG_CONST_STACK_SIZE
,
2409 static const struct bpf_func_proto
*
2410 sk_filter_func_proto(enum bpf_func_id func_id
)
2413 case BPF_FUNC_map_lookup_elem
:
2414 return &bpf_map_lookup_elem_proto
;
2415 case BPF_FUNC_map_update_elem
:
2416 return &bpf_map_update_elem_proto
;
2417 case BPF_FUNC_map_delete_elem
:
2418 return &bpf_map_delete_elem_proto
;
2419 case BPF_FUNC_get_prandom_u32
:
2420 return &bpf_get_prandom_u32_proto
;
2421 case BPF_FUNC_get_smp_processor_id
:
2422 return &bpf_get_raw_smp_processor_id_proto
;
2423 case BPF_FUNC_tail_call
:
2424 return &bpf_tail_call_proto
;
2425 case BPF_FUNC_ktime_get_ns
:
2426 return &bpf_ktime_get_ns_proto
;
2427 case BPF_FUNC_trace_printk
:
2428 if (capable(CAP_SYS_ADMIN
))
2429 return bpf_get_trace_printk_proto();
2435 static const struct bpf_func_proto
*
2436 tc_cls_act_func_proto(enum bpf_func_id func_id
)
2439 case BPF_FUNC_skb_store_bytes
:
2440 return &bpf_skb_store_bytes_proto
;
2441 case BPF_FUNC_skb_load_bytes
:
2442 return &bpf_skb_load_bytes_proto
;
2443 case BPF_FUNC_csum_diff
:
2444 return &bpf_csum_diff_proto
;
2445 case BPF_FUNC_l3_csum_replace
:
2446 return &bpf_l3_csum_replace_proto
;
2447 case BPF_FUNC_l4_csum_replace
:
2448 return &bpf_l4_csum_replace_proto
;
2449 case BPF_FUNC_clone_redirect
:
2450 return &bpf_clone_redirect_proto
;
2451 case BPF_FUNC_get_cgroup_classid
:
2452 return &bpf_get_cgroup_classid_proto
;
2453 case BPF_FUNC_skb_vlan_push
:
2454 return &bpf_skb_vlan_push_proto
;
2455 case BPF_FUNC_skb_vlan_pop
:
2456 return &bpf_skb_vlan_pop_proto
;
2457 case BPF_FUNC_skb_change_proto
:
2458 return &bpf_skb_change_proto_proto
;
2459 case BPF_FUNC_skb_change_type
:
2460 return &bpf_skb_change_type_proto
;
2461 case BPF_FUNC_skb_change_tail
:
2462 return &bpf_skb_change_tail_proto
;
2463 case BPF_FUNC_skb_get_tunnel_key
:
2464 return &bpf_skb_get_tunnel_key_proto
;
2465 case BPF_FUNC_skb_set_tunnel_key
:
2466 return bpf_get_skb_set_tunnel_proto(func_id
);
2467 case BPF_FUNC_skb_get_tunnel_opt
:
2468 return &bpf_skb_get_tunnel_opt_proto
;
2469 case BPF_FUNC_skb_set_tunnel_opt
:
2470 return bpf_get_skb_set_tunnel_proto(func_id
);
2471 case BPF_FUNC_redirect
:
2472 return &bpf_redirect_proto
;
2473 case BPF_FUNC_get_route_realm
:
2474 return &bpf_get_route_realm_proto
;
2475 case BPF_FUNC_get_hash_recalc
:
2476 return &bpf_get_hash_recalc_proto
;
2477 case BPF_FUNC_perf_event_output
:
2478 return &bpf_skb_event_output_proto
;
2479 case BPF_FUNC_get_smp_processor_id
:
2480 return &bpf_get_smp_processor_id_proto
;
2481 case BPF_FUNC_skb_under_cgroup
:
2482 return &bpf_skb_under_cgroup_proto
;
2484 return sk_filter_func_proto(func_id
);
2488 static const struct bpf_func_proto
*
2489 xdp_func_proto(enum bpf_func_id func_id
)
2492 case BPF_FUNC_perf_event_output
:
2493 return &bpf_xdp_event_output_proto
;
2495 return sk_filter_func_proto(func_id
);
2499 static bool __is_valid_access(int off
, int size
, enum bpf_access_type type
)
2501 if (off
< 0 || off
>= sizeof(struct __sk_buff
))
2503 /* The verifier guarantees that size > 0. */
2504 if (off
% size
!= 0)
2506 if (size
!= sizeof(__u32
))
2512 static bool sk_filter_is_valid_access(int off
, int size
,
2513 enum bpf_access_type type
,
2514 enum bpf_reg_type
*reg_type
)
2517 case offsetof(struct __sk_buff
, tc_classid
):
2518 case offsetof(struct __sk_buff
, data
):
2519 case offsetof(struct __sk_buff
, data_end
):
2523 if (type
== BPF_WRITE
) {
2525 case offsetof(struct __sk_buff
, cb
[0]) ...
2526 offsetof(struct __sk_buff
, cb
[4]):
2533 return __is_valid_access(off
, size
, type
);
2536 static bool tc_cls_act_is_valid_access(int off
, int size
,
2537 enum bpf_access_type type
,
2538 enum bpf_reg_type
*reg_type
)
2540 if (type
== BPF_WRITE
) {
2542 case offsetof(struct __sk_buff
, mark
):
2543 case offsetof(struct __sk_buff
, tc_index
):
2544 case offsetof(struct __sk_buff
, priority
):
2545 case offsetof(struct __sk_buff
, cb
[0]) ...
2546 offsetof(struct __sk_buff
, cb
[4]):
2547 case offsetof(struct __sk_buff
, tc_classid
):
2555 case offsetof(struct __sk_buff
, data
):
2556 *reg_type
= PTR_TO_PACKET
;
2558 case offsetof(struct __sk_buff
, data_end
):
2559 *reg_type
= PTR_TO_PACKET_END
;
2563 return __is_valid_access(off
, size
, type
);
2566 static bool __is_valid_xdp_access(int off
, int size
,
2567 enum bpf_access_type type
)
2569 if (off
< 0 || off
>= sizeof(struct xdp_md
))
2571 if (off
% size
!= 0)
2573 if (size
!= sizeof(__u32
))
2579 static bool xdp_is_valid_access(int off
, int size
,
2580 enum bpf_access_type type
,
2581 enum bpf_reg_type
*reg_type
)
2583 if (type
== BPF_WRITE
)
2587 case offsetof(struct xdp_md
, data
):
2588 *reg_type
= PTR_TO_PACKET
;
2590 case offsetof(struct xdp_md
, data_end
):
2591 *reg_type
= PTR_TO_PACKET_END
;
2595 return __is_valid_xdp_access(off
, size
, type
);
2598 void bpf_warn_invalid_xdp_action(u32 act
)
2600 WARN_ONCE(1, "Illegal XDP return value %u, expect packet loss\n", act
);
2602 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action
);
2604 static u32
sk_filter_convert_ctx_access(enum bpf_access_type type
, int dst_reg
,
2605 int src_reg
, int ctx_off
,
2606 struct bpf_insn
*insn_buf
,
2607 struct bpf_prog
*prog
)
2609 struct bpf_insn
*insn
= insn_buf
;
2612 case offsetof(struct __sk_buff
, len
):
2613 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, len
) != 4);
2615 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2616 offsetof(struct sk_buff
, len
));
2619 case offsetof(struct __sk_buff
, protocol
):
2620 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, protocol
) != 2);
2622 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
2623 offsetof(struct sk_buff
, protocol
));
2626 case offsetof(struct __sk_buff
, vlan_proto
):
2627 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, vlan_proto
) != 2);
2629 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
2630 offsetof(struct sk_buff
, vlan_proto
));
2633 case offsetof(struct __sk_buff
, priority
):
2634 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, priority
) != 4);
2636 if (type
== BPF_WRITE
)
2637 *insn
++ = BPF_STX_MEM(BPF_W
, dst_reg
, src_reg
,
2638 offsetof(struct sk_buff
, priority
));
2640 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2641 offsetof(struct sk_buff
, priority
));
2644 case offsetof(struct __sk_buff
, ingress_ifindex
):
2645 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, skb_iif
) != 4);
2647 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2648 offsetof(struct sk_buff
, skb_iif
));
2651 case offsetof(struct __sk_buff
, ifindex
):
2652 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device
, ifindex
) != 4);
2654 *insn
++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff
, dev
),
2656 offsetof(struct sk_buff
, dev
));
2657 *insn
++ = BPF_JMP_IMM(BPF_JEQ
, dst_reg
, 0, 1);
2658 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, dst_reg
,
2659 offsetof(struct net_device
, ifindex
));
2662 case offsetof(struct __sk_buff
, hash
):
2663 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, hash
) != 4);
2665 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2666 offsetof(struct sk_buff
, hash
));
2669 case offsetof(struct __sk_buff
, mark
):
2670 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, mark
) != 4);
2672 if (type
== BPF_WRITE
)
2673 *insn
++ = BPF_STX_MEM(BPF_W
, dst_reg
, src_reg
,
2674 offsetof(struct sk_buff
, mark
));
2676 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2677 offsetof(struct sk_buff
, mark
));
2680 case offsetof(struct __sk_buff
, pkt_type
):
2681 return convert_skb_access(SKF_AD_PKTTYPE
, dst_reg
, src_reg
, insn
);
2683 case offsetof(struct __sk_buff
, queue_mapping
):
2684 return convert_skb_access(SKF_AD_QUEUE
, dst_reg
, src_reg
, insn
);
2686 case offsetof(struct __sk_buff
, vlan_present
):
2687 return convert_skb_access(SKF_AD_VLAN_TAG_PRESENT
,
2688 dst_reg
, src_reg
, insn
);
2690 case offsetof(struct __sk_buff
, vlan_tci
):
2691 return convert_skb_access(SKF_AD_VLAN_TAG
,
2692 dst_reg
, src_reg
, insn
);
2694 case offsetof(struct __sk_buff
, cb
[0]) ...
2695 offsetof(struct __sk_buff
, cb
[4]):
2696 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb
, data
) < 20);
2698 prog
->cb_access
= 1;
2699 ctx_off
-= offsetof(struct __sk_buff
, cb
[0]);
2700 ctx_off
+= offsetof(struct sk_buff
, cb
);
2701 ctx_off
+= offsetof(struct qdisc_skb_cb
, data
);
2702 if (type
== BPF_WRITE
)
2703 *insn
++ = BPF_STX_MEM(BPF_W
, dst_reg
, src_reg
, ctx_off
);
2705 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
, ctx_off
);
2708 case offsetof(struct __sk_buff
, tc_classid
):
2709 ctx_off
-= offsetof(struct __sk_buff
, tc_classid
);
2710 ctx_off
+= offsetof(struct sk_buff
, cb
);
2711 ctx_off
+= offsetof(struct qdisc_skb_cb
, tc_classid
);
2712 if (type
== BPF_WRITE
)
2713 *insn
++ = BPF_STX_MEM(BPF_H
, dst_reg
, src_reg
, ctx_off
);
2715 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
, ctx_off
);
2718 case offsetof(struct __sk_buff
, data
):
2719 *insn
++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff
, data
),
2721 offsetof(struct sk_buff
, data
));
2724 case offsetof(struct __sk_buff
, data_end
):
2725 ctx_off
-= offsetof(struct __sk_buff
, data_end
);
2726 ctx_off
+= offsetof(struct sk_buff
, cb
);
2727 ctx_off
+= offsetof(struct bpf_skb_data_end
, data_end
);
2728 *insn
++ = BPF_LDX_MEM(BPF_SIZEOF(void *), dst_reg
, src_reg
,
2732 case offsetof(struct __sk_buff
, tc_index
):
2733 #ifdef CONFIG_NET_SCHED
2734 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, tc_index
) != 2);
2736 if (type
== BPF_WRITE
)
2737 *insn
++ = BPF_STX_MEM(BPF_H
, dst_reg
, src_reg
,
2738 offsetof(struct sk_buff
, tc_index
));
2740 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
2741 offsetof(struct sk_buff
, tc_index
));
2744 if (type
== BPF_WRITE
)
2745 *insn
++ = BPF_MOV64_REG(dst_reg
, dst_reg
);
2747 *insn
++ = BPF_MOV64_IMM(dst_reg
, 0);
2752 return insn
- insn_buf
;
2755 static u32
tc_cls_act_convert_ctx_access(enum bpf_access_type type
, int dst_reg
,
2756 int src_reg
, int ctx_off
,
2757 struct bpf_insn
*insn_buf
,
2758 struct bpf_prog
*prog
)
2760 struct bpf_insn
*insn
= insn_buf
;
2763 case offsetof(struct __sk_buff
, ifindex
):
2764 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device
, ifindex
) != 4);
2766 *insn
++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff
, dev
),
2768 offsetof(struct sk_buff
, dev
));
2769 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, dst_reg
,
2770 offsetof(struct net_device
, ifindex
));
2773 return sk_filter_convert_ctx_access(type
, dst_reg
, src_reg
,
2774 ctx_off
, insn_buf
, prog
);
2777 return insn
- insn_buf
;
2780 static u32
xdp_convert_ctx_access(enum bpf_access_type type
, int dst_reg
,
2781 int src_reg
, int ctx_off
,
2782 struct bpf_insn
*insn_buf
,
2783 struct bpf_prog
*prog
)
2785 struct bpf_insn
*insn
= insn_buf
;
2788 case offsetof(struct xdp_md
, data
):
2789 *insn
++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff
, data
),
2791 offsetof(struct xdp_buff
, data
));
2793 case offsetof(struct xdp_md
, data_end
):
2794 *insn
++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff
, data_end
),
2796 offsetof(struct xdp_buff
, data_end
));
2800 return insn
- insn_buf
;
2803 static const struct bpf_verifier_ops sk_filter_ops
= {
2804 .get_func_proto
= sk_filter_func_proto
,
2805 .is_valid_access
= sk_filter_is_valid_access
,
2806 .convert_ctx_access
= sk_filter_convert_ctx_access
,
2809 static const struct bpf_verifier_ops tc_cls_act_ops
= {
2810 .get_func_proto
= tc_cls_act_func_proto
,
2811 .is_valid_access
= tc_cls_act_is_valid_access
,
2812 .convert_ctx_access
= tc_cls_act_convert_ctx_access
,
2815 static const struct bpf_verifier_ops xdp_ops
= {
2816 .get_func_proto
= xdp_func_proto
,
2817 .is_valid_access
= xdp_is_valid_access
,
2818 .convert_ctx_access
= xdp_convert_ctx_access
,
2821 static struct bpf_prog_type_list sk_filter_type __read_mostly
= {
2822 .ops
= &sk_filter_ops
,
2823 .type
= BPF_PROG_TYPE_SOCKET_FILTER
,
2826 static struct bpf_prog_type_list sched_cls_type __read_mostly
= {
2827 .ops
= &tc_cls_act_ops
,
2828 .type
= BPF_PROG_TYPE_SCHED_CLS
,
2831 static struct bpf_prog_type_list sched_act_type __read_mostly
= {
2832 .ops
= &tc_cls_act_ops
,
2833 .type
= BPF_PROG_TYPE_SCHED_ACT
,
2836 static struct bpf_prog_type_list xdp_type __read_mostly
= {
2838 .type
= BPF_PROG_TYPE_XDP
,
2841 static int __init
register_sk_filter_ops(void)
2843 bpf_register_prog_type(&sk_filter_type
);
2844 bpf_register_prog_type(&sched_cls_type
);
2845 bpf_register_prog_type(&sched_act_type
);
2846 bpf_register_prog_type(&xdp_type
);
2850 late_initcall(register_sk_filter_ops
);
2852 int sk_detach_filter(struct sock
*sk
)
2855 struct sk_filter
*filter
;
2857 if (sock_flag(sk
, SOCK_FILTER_LOCKED
))
2860 filter
= rcu_dereference_protected(sk
->sk_filter
,
2861 lockdep_sock_is_held(sk
));
2863 RCU_INIT_POINTER(sk
->sk_filter
, NULL
);
2864 sk_filter_uncharge(sk
, filter
);
2870 EXPORT_SYMBOL_GPL(sk_detach_filter
);
2872 int sk_get_filter(struct sock
*sk
, struct sock_filter __user
*ubuf
,
2875 struct sock_fprog_kern
*fprog
;
2876 struct sk_filter
*filter
;
2880 filter
= rcu_dereference_protected(sk
->sk_filter
,
2881 lockdep_sock_is_held(sk
));
2885 /* We're copying the filter that has been originally attached,
2886 * so no conversion/decode needed anymore. eBPF programs that
2887 * have no original program cannot be dumped through this.
2890 fprog
= filter
->prog
->orig_prog
;
2896 /* User space only enquires number of filter blocks. */
2900 if (len
< fprog
->len
)
2904 if (copy_to_user(ubuf
, fprog
->filter
, bpf_classic_proglen(fprog
)))
2907 /* Instead of bytes, the API requests to return the number