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 - run a packet through a socket filter
57 * @sk: sock associated with &sk_buff
58 * @skb: buffer to filter
60 * Run the eBPF program and then cut skb->data to correct size returned by
61 * the program. If pkt_len is 0 we toss packet. If skb->len is smaller
62 * than pkt_len we keep whole skb->data. This is the socket level
63 * wrapper to BPF_PROG_RUN. It returns 0 if the packet should
64 * be accepted or -EPERM if the packet should be tossed.
67 int sk_filter(struct sock
*sk
, struct sk_buff
*skb
)
70 struct sk_filter
*filter
;
73 * If the skb was allocated from pfmemalloc reserves, only
74 * allow SOCK_MEMALLOC sockets to use it as this socket is
77 if (skb_pfmemalloc(skb
) && !sock_flag(sk
, SOCK_MEMALLOC
))
80 err
= security_sock_rcv_skb(sk
, skb
);
85 filter
= rcu_dereference(sk
->sk_filter
);
87 unsigned int pkt_len
= bpf_prog_run_save_cb(filter
->prog
, skb
);
89 err
= pkt_len
? pskb_trim(skb
, pkt_len
) : -EPERM
;
95 EXPORT_SYMBOL(sk_filter
);
97 static u64
__skb_get_pay_offset(u64 ctx
, u64 a
, u64 x
, u64 r4
, u64 r5
)
99 return skb_get_poff((struct sk_buff
*)(unsigned long) ctx
);
102 static u64
__skb_get_nlattr(u64 ctx
, u64 a
, u64 x
, u64 r4
, u64 r5
)
104 struct sk_buff
*skb
= (struct sk_buff
*)(unsigned long) ctx
;
107 if (skb_is_nonlinear(skb
))
110 if (skb
->len
< sizeof(struct nlattr
))
113 if (a
> skb
->len
- sizeof(struct nlattr
))
116 nla
= nla_find((struct nlattr
*) &skb
->data
[a
], skb
->len
- a
, x
);
118 return (void *) nla
- (void *) skb
->data
;
123 static u64
__skb_get_nlattr_nest(u64 ctx
, u64 a
, u64 x
, u64 r4
, u64 r5
)
125 struct sk_buff
*skb
= (struct sk_buff
*)(unsigned long) ctx
;
128 if (skb_is_nonlinear(skb
))
131 if (skb
->len
< sizeof(struct nlattr
))
134 if (a
> skb
->len
- sizeof(struct nlattr
))
137 nla
= (struct nlattr
*) &skb
->data
[a
];
138 if (nla
->nla_len
> skb
->len
- a
)
141 nla
= nla_find_nested(nla
, x
);
143 return (void *) nla
- (void *) skb
->data
;
148 static u64
__get_raw_cpu_id(u64 ctx
, u64 a
, u64 x
, u64 r4
, u64 r5
)
150 return raw_smp_processor_id();
153 static u32
convert_skb_access(int skb_field
, int dst_reg
, int src_reg
,
154 struct bpf_insn
*insn_buf
)
156 struct bpf_insn
*insn
= insn_buf
;
160 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, mark
) != 4);
162 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
163 offsetof(struct sk_buff
, mark
));
167 *insn
++ = BPF_LDX_MEM(BPF_B
, dst_reg
, src_reg
, PKT_TYPE_OFFSET());
168 *insn
++ = BPF_ALU32_IMM(BPF_AND
, dst_reg
, PKT_TYPE_MAX
);
169 #ifdef __BIG_ENDIAN_BITFIELD
170 *insn
++ = BPF_ALU32_IMM(BPF_RSH
, dst_reg
, 5);
175 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, queue_mapping
) != 2);
177 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
178 offsetof(struct sk_buff
, queue_mapping
));
181 case SKF_AD_VLAN_TAG
:
182 case SKF_AD_VLAN_TAG_PRESENT
:
183 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, vlan_tci
) != 2);
184 BUILD_BUG_ON(VLAN_TAG_PRESENT
!= 0x1000);
186 /* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
187 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
188 offsetof(struct sk_buff
, vlan_tci
));
189 if (skb_field
== SKF_AD_VLAN_TAG
) {
190 *insn
++ = BPF_ALU32_IMM(BPF_AND
, dst_reg
,
194 *insn
++ = BPF_ALU32_IMM(BPF_RSH
, dst_reg
, 12);
196 *insn
++ = BPF_ALU32_IMM(BPF_AND
, dst_reg
, 1);
201 return insn
- insn_buf
;
204 static bool convert_bpf_extensions(struct sock_filter
*fp
,
205 struct bpf_insn
**insnp
)
207 struct bpf_insn
*insn
= *insnp
;
211 case SKF_AD_OFF
+ SKF_AD_PROTOCOL
:
212 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, protocol
) != 2);
214 /* A = *(u16 *) (CTX + offsetof(protocol)) */
215 *insn
++ = BPF_LDX_MEM(BPF_H
, BPF_REG_A
, BPF_REG_CTX
,
216 offsetof(struct sk_buff
, protocol
));
217 /* A = ntohs(A) [emitting a nop or swap16] */
218 *insn
= BPF_ENDIAN(BPF_FROM_BE
, BPF_REG_A
, 16);
221 case SKF_AD_OFF
+ SKF_AD_PKTTYPE
:
222 cnt
= convert_skb_access(SKF_AD_PKTTYPE
, BPF_REG_A
, BPF_REG_CTX
, insn
);
226 case SKF_AD_OFF
+ SKF_AD_IFINDEX
:
227 case SKF_AD_OFF
+ SKF_AD_HATYPE
:
228 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device
, ifindex
) != 4);
229 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device
, type
) != 2);
230 BUILD_BUG_ON(bytes_to_bpf_size(FIELD_SIZEOF(struct sk_buff
, dev
)) < 0);
232 *insn
++ = BPF_LDX_MEM(bytes_to_bpf_size(FIELD_SIZEOF(struct sk_buff
, dev
)),
233 BPF_REG_TMP
, BPF_REG_CTX
,
234 offsetof(struct sk_buff
, dev
));
235 /* if (tmp != 0) goto pc + 1 */
236 *insn
++ = BPF_JMP_IMM(BPF_JNE
, BPF_REG_TMP
, 0, 1);
237 *insn
++ = BPF_EXIT_INSN();
238 if (fp
->k
== SKF_AD_OFF
+ SKF_AD_IFINDEX
)
239 *insn
= BPF_LDX_MEM(BPF_W
, BPF_REG_A
, BPF_REG_TMP
,
240 offsetof(struct net_device
, ifindex
));
242 *insn
= BPF_LDX_MEM(BPF_H
, BPF_REG_A
, BPF_REG_TMP
,
243 offsetof(struct net_device
, type
));
246 case SKF_AD_OFF
+ SKF_AD_MARK
:
247 cnt
= convert_skb_access(SKF_AD_MARK
, BPF_REG_A
, BPF_REG_CTX
, insn
);
251 case SKF_AD_OFF
+ SKF_AD_RXHASH
:
252 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, hash
) != 4);
254 *insn
= BPF_LDX_MEM(BPF_W
, BPF_REG_A
, BPF_REG_CTX
,
255 offsetof(struct sk_buff
, hash
));
258 case SKF_AD_OFF
+ SKF_AD_QUEUE
:
259 cnt
= convert_skb_access(SKF_AD_QUEUE
, BPF_REG_A
, BPF_REG_CTX
, insn
);
263 case SKF_AD_OFF
+ SKF_AD_VLAN_TAG
:
264 cnt
= convert_skb_access(SKF_AD_VLAN_TAG
,
265 BPF_REG_A
, BPF_REG_CTX
, insn
);
269 case SKF_AD_OFF
+ SKF_AD_VLAN_TAG_PRESENT
:
270 cnt
= convert_skb_access(SKF_AD_VLAN_TAG_PRESENT
,
271 BPF_REG_A
, BPF_REG_CTX
, insn
);
275 case SKF_AD_OFF
+ SKF_AD_VLAN_TPID
:
276 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, vlan_proto
) != 2);
278 /* A = *(u16 *) (CTX + offsetof(vlan_proto)) */
279 *insn
++ = BPF_LDX_MEM(BPF_H
, BPF_REG_A
, BPF_REG_CTX
,
280 offsetof(struct sk_buff
, vlan_proto
));
281 /* A = ntohs(A) [emitting a nop or swap16] */
282 *insn
= BPF_ENDIAN(BPF_FROM_BE
, BPF_REG_A
, 16);
285 case SKF_AD_OFF
+ SKF_AD_PAY_OFFSET
:
286 case SKF_AD_OFF
+ SKF_AD_NLATTR
:
287 case SKF_AD_OFF
+ SKF_AD_NLATTR_NEST
:
288 case SKF_AD_OFF
+ SKF_AD_CPU
:
289 case SKF_AD_OFF
+ SKF_AD_RANDOM
:
291 *insn
++ = BPF_MOV64_REG(BPF_REG_ARG1
, BPF_REG_CTX
);
293 *insn
++ = BPF_MOV64_REG(BPF_REG_ARG2
, BPF_REG_A
);
295 *insn
++ = BPF_MOV64_REG(BPF_REG_ARG3
, BPF_REG_X
);
296 /* Emit call(arg1=CTX, arg2=A, arg3=X) */
298 case SKF_AD_OFF
+ SKF_AD_PAY_OFFSET
:
299 *insn
= BPF_EMIT_CALL(__skb_get_pay_offset
);
301 case SKF_AD_OFF
+ SKF_AD_NLATTR
:
302 *insn
= BPF_EMIT_CALL(__skb_get_nlattr
);
304 case SKF_AD_OFF
+ SKF_AD_NLATTR_NEST
:
305 *insn
= BPF_EMIT_CALL(__skb_get_nlattr_nest
);
307 case SKF_AD_OFF
+ SKF_AD_CPU
:
308 *insn
= BPF_EMIT_CALL(__get_raw_cpu_id
);
310 case SKF_AD_OFF
+ SKF_AD_RANDOM
:
311 *insn
= BPF_EMIT_CALL(bpf_user_rnd_u32
);
312 bpf_user_rnd_init_once();
317 case SKF_AD_OFF
+ SKF_AD_ALU_XOR_X
:
319 *insn
= BPF_ALU32_REG(BPF_XOR
, BPF_REG_A
, BPF_REG_X
);
323 /* This is just a dummy call to avoid letting the compiler
324 * evict __bpf_call_base() as an optimization. Placed here
325 * where no-one bothers.
327 BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0);
336 * bpf_convert_filter - convert filter program
337 * @prog: the user passed filter program
338 * @len: the length of the user passed filter program
339 * @new_prog: buffer where converted program will be stored
340 * @new_len: pointer to store length of converted program
342 * Remap 'sock_filter' style BPF instruction set to 'sock_filter_ext' style.
343 * Conversion workflow:
345 * 1) First pass for calculating the new program length:
346 * bpf_convert_filter(old_prog, old_len, NULL, &new_len)
348 * 2) 2nd pass to remap in two passes: 1st pass finds new
349 * jump offsets, 2nd pass remapping:
350 * new_prog = kmalloc(sizeof(struct bpf_insn) * new_len);
351 * bpf_convert_filter(old_prog, old_len, new_prog, &new_len);
353 static int bpf_convert_filter(struct sock_filter
*prog
, int len
,
354 struct bpf_insn
*new_prog
, int *new_len
)
356 int new_flen
= 0, pass
= 0, target
, i
;
357 struct bpf_insn
*new_insn
;
358 struct sock_filter
*fp
;
362 BUILD_BUG_ON(BPF_MEMWORDS
* sizeof(u32
) > MAX_BPF_STACK
);
363 BUILD_BUG_ON(BPF_REG_FP
+ 1 != MAX_BPF_REG
);
365 if (len
<= 0 || len
> BPF_MAXINSNS
)
369 addrs
= kcalloc(len
, sizeof(*addrs
),
370 GFP_KERNEL
| __GFP_NOWARN
);
379 /* Classic BPF related prologue emission. */
381 /* Classic BPF expects A and X to be reset first. These need
382 * to be guaranteed to be the first two instructions.
384 *new_insn
++ = BPF_ALU64_REG(BPF_XOR
, BPF_REG_A
, BPF_REG_A
);
385 *new_insn
++ = BPF_ALU64_REG(BPF_XOR
, BPF_REG_X
, BPF_REG_X
);
387 /* All programs must keep CTX in callee saved BPF_REG_CTX.
388 * In eBPF case it's done by the compiler, here we need to
389 * do this ourself. Initial CTX is present in BPF_REG_ARG1.
391 *new_insn
++ = BPF_MOV64_REG(BPF_REG_CTX
, BPF_REG_ARG1
);
396 for (i
= 0; i
< len
; fp
++, i
++) {
397 struct bpf_insn tmp_insns
[6] = { };
398 struct bpf_insn
*insn
= tmp_insns
;
401 addrs
[i
] = new_insn
- new_prog
;
404 /* All arithmetic insns and skb loads map as-is. */
405 case BPF_ALU
| BPF_ADD
| BPF_X
:
406 case BPF_ALU
| BPF_ADD
| BPF_K
:
407 case BPF_ALU
| BPF_SUB
| BPF_X
:
408 case BPF_ALU
| BPF_SUB
| BPF_K
:
409 case BPF_ALU
| BPF_AND
| BPF_X
:
410 case BPF_ALU
| BPF_AND
| BPF_K
:
411 case BPF_ALU
| BPF_OR
| BPF_X
:
412 case BPF_ALU
| BPF_OR
| BPF_K
:
413 case BPF_ALU
| BPF_LSH
| BPF_X
:
414 case BPF_ALU
| BPF_LSH
| BPF_K
:
415 case BPF_ALU
| BPF_RSH
| BPF_X
:
416 case BPF_ALU
| BPF_RSH
| BPF_K
:
417 case BPF_ALU
| BPF_XOR
| BPF_X
:
418 case BPF_ALU
| BPF_XOR
| BPF_K
:
419 case BPF_ALU
| BPF_MUL
| BPF_X
:
420 case BPF_ALU
| BPF_MUL
| BPF_K
:
421 case BPF_ALU
| BPF_DIV
| BPF_X
:
422 case BPF_ALU
| BPF_DIV
| BPF_K
:
423 case BPF_ALU
| BPF_MOD
| BPF_X
:
424 case BPF_ALU
| BPF_MOD
| BPF_K
:
425 case BPF_ALU
| BPF_NEG
:
426 case BPF_LD
| BPF_ABS
| BPF_W
:
427 case BPF_LD
| BPF_ABS
| BPF_H
:
428 case BPF_LD
| BPF_ABS
| BPF_B
:
429 case BPF_LD
| BPF_IND
| BPF_W
:
430 case BPF_LD
| BPF_IND
| BPF_H
:
431 case BPF_LD
| BPF_IND
| BPF_B
:
432 /* Check for overloaded BPF extension and
433 * directly convert it if found, otherwise
434 * just move on with mapping.
436 if (BPF_CLASS(fp
->code
) == BPF_LD
&&
437 BPF_MODE(fp
->code
) == BPF_ABS
&&
438 convert_bpf_extensions(fp
, &insn
))
441 *insn
= BPF_RAW_INSN(fp
->code
, BPF_REG_A
, BPF_REG_X
, 0, fp
->k
);
444 /* Jump transformation cannot use BPF block macros
445 * everywhere as offset calculation and target updates
446 * require a bit more work than the rest, i.e. jump
447 * opcodes map as-is, but offsets need adjustment.
450 #define BPF_EMIT_JMP \
452 if (target >= len || target < 0) \
454 insn->off = addrs ? addrs[target] - addrs[i] - 1 : 0; \
455 /* Adjust pc relative offset for 2nd or 3rd insn. */ \
456 insn->off -= insn - tmp_insns; \
459 case BPF_JMP
| BPF_JA
:
460 target
= i
+ fp
->k
+ 1;
461 insn
->code
= fp
->code
;
465 case BPF_JMP
| BPF_JEQ
| BPF_K
:
466 case BPF_JMP
| BPF_JEQ
| BPF_X
:
467 case BPF_JMP
| BPF_JSET
| BPF_K
:
468 case BPF_JMP
| BPF_JSET
| BPF_X
:
469 case BPF_JMP
| BPF_JGT
| BPF_K
:
470 case BPF_JMP
| BPF_JGT
| BPF_X
:
471 case BPF_JMP
| BPF_JGE
| BPF_K
:
472 case BPF_JMP
| BPF_JGE
| BPF_X
:
473 if (BPF_SRC(fp
->code
) == BPF_K
&& (int) fp
->k
< 0) {
474 /* BPF immediates are signed, zero extend
475 * immediate into tmp register and use it
478 *insn
++ = BPF_MOV32_IMM(BPF_REG_TMP
, fp
->k
);
480 insn
->dst_reg
= BPF_REG_A
;
481 insn
->src_reg
= BPF_REG_TMP
;
484 insn
->dst_reg
= BPF_REG_A
;
486 bpf_src
= BPF_SRC(fp
->code
);
487 insn
->src_reg
= bpf_src
== BPF_X
? BPF_REG_X
: 0;
490 /* Common case where 'jump_false' is next insn. */
492 insn
->code
= BPF_JMP
| BPF_OP(fp
->code
) | bpf_src
;
493 target
= i
+ fp
->jt
+ 1;
498 /* Convert JEQ into JNE when 'jump_true' is next insn. */
499 if (fp
->jt
== 0 && BPF_OP(fp
->code
) == BPF_JEQ
) {
500 insn
->code
= BPF_JMP
| BPF_JNE
| bpf_src
;
501 target
= i
+ fp
->jf
+ 1;
506 /* Other jumps are mapped into two insns: Jxx and JA. */
507 target
= i
+ fp
->jt
+ 1;
508 insn
->code
= BPF_JMP
| BPF_OP(fp
->code
) | bpf_src
;
512 insn
->code
= BPF_JMP
| BPF_JA
;
513 target
= i
+ fp
->jf
+ 1;
517 /* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */
518 case BPF_LDX
| BPF_MSH
| BPF_B
:
520 *insn
++ = BPF_MOV64_REG(BPF_REG_TMP
, BPF_REG_A
);
521 /* A = BPF_R0 = *(u8 *) (skb->data + K) */
522 *insn
++ = BPF_LD_ABS(BPF_B
, fp
->k
);
524 *insn
++ = BPF_ALU32_IMM(BPF_AND
, BPF_REG_A
, 0xf);
526 *insn
++ = BPF_ALU32_IMM(BPF_LSH
, BPF_REG_A
, 2);
528 *insn
++ = BPF_MOV64_REG(BPF_REG_X
, BPF_REG_A
);
530 *insn
= BPF_MOV64_REG(BPF_REG_A
, BPF_REG_TMP
);
533 /* RET_K is remaped into 2 insns. RET_A case doesn't need an
534 * extra mov as BPF_REG_0 is already mapped into BPF_REG_A.
536 case BPF_RET
| BPF_A
:
537 case BPF_RET
| BPF_K
:
538 if (BPF_RVAL(fp
->code
) == BPF_K
)
539 *insn
++ = BPF_MOV32_RAW(BPF_K
, BPF_REG_0
,
541 *insn
= BPF_EXIT_INSN();
544 /* Store to stack. */
547 *insn
= BPF_STX_MEM(BPF_W
, BPF_REG_FP
, BPF_CLASS(fp
->code
) ==
548 BPF_ST
? BPF_REG_A
: BPF_REG_X
,
549 -(BPF_MEMWORDS
- fp
->k
) * 4);
552 /* Load from stack. */
553 case BPF_LD
| BPF_MEM
:
554 case BPF_LDX
| BPF_MEM
:
555 *insn
= BPF_LDX_MEM(BPF_W
, BPF_CLASS(fp
->code
) == BPF_LD
?
556 BPF_REG_A
: BPF_REG_X
, BPF_REG_FP
,
557 -(BPF_MEMWORDS
- fp
->k
) * 4);
561 case BPF_LD
| BPF_IMM
:
562 case BPF_LDX
| BPF_IMM
:
563 *insn
= BPF_MOV32_IMM(BPF_CLASS(fp
->code
) == BPF_LD
?
564 BPF_REG_A
: BPF_REG_X
, fp
->k
);
568 case BPF_MISC
| BPF_TAX
:
569 *insn
= BPF_MOV64_REG(BPF_REG_X
, BPF_REG_A
);
573 case BPF_MISC
| BPF_TXA
:
574 *insn
= BPF_MOV64_REG(BPF_REG_A
, BPF_REG_X
);
577 /* A = skb->len or X = skb->len */
578 case BPF_LD
| BPF_W
| BPF_LEN
:
579 case BPF_LDX
| BPF_W
| BPF_LEN
:
580 *insn
= BPF_LDX_MEM(BPF_W
, BPF_CLASS(fp
->code
) == BPF_LD
?
581 BPF_REG_A
: BPF_REG_X
, BPF_REG_CTX
,
582 offsetof(struct sk_buff
, len
));
585 /* Access seccomp_data fields. */
586 case BPF_LDX
| BPF_ABS
| BPF_W
:
587 /* A = *(u32 *) (ctx + K) */
588 *insn
= BPF_LDX_MEM(BPF_W
, BPF_REG_A
, BPF_REG_CTX
, fp
->k
);
591 /* Unknown instruction. */
598 memcpy(new_insn
, tmp_insns
,
599 sizeof(*insn
) * (insn
- tmp_insns
));
600 new_insn
+= insn
- tmp_insns
;
604 /* Only calculating new length. */
605 *new_len
= new_insn
- new_prog
;
610 if (new_flen
!= new_insn
- new_prog
) {
611 new_flen
= new_insn
- new_prog
;
618 BUG_ON(*new_len
!= new_flen
);
627 * As we dont want to clear mem[] array for each packet going through
628 * __bpf_prog_run(), we check that filter loaded by user never try to read
629 * a cell if not previously written, and we check all branches to be sure
630 * a malicious user doesn't try to abuse us.
632 static int check_load_and_stores(const struct sock_filter
*filter
, int flen
)
634 u16
*masks
, memvalid
= 0; /* One bit per cell, 16 cells */
637 BUILD_BUG_ON(BPF_MEMWORDS
> 16);
639 masks
= kmalloc_array(flen
, sizeof(*masks
), GFP_KERNEL
);
643 memset(masks
, 0xff, flen
* sizeof(*masks
));
645 for (pc
= 0; pc
< flen
; pc
++) {
646 memvalid
&= masks
[pc
];
648 switch (filter
[pc
].code
) {
651 memvalid
|= (1 << filter
[pc
].k
);
653 case BPF_LD
| BPF_MEM
:
654 case BPF_LDX
| BPF_MEM
:
655 if (!(memvalid
& (1 << filter
[pc
].k
))) {
660 case BPF_JMP
| BPF_JA
:
661 /* A jump must set masks on target */
662 masks
[pc
+ 1 + filter
[pc
].k
] &= memvalid
;
665 case BPF_JMP
| BPF_JEQ
| BPF_K
:
666 case BPF_JMP
| BPF_JEQ
| BPF_X
:
667 case BPF_JMP
| BPF_JGE
| BPF_K
:
668 case BPF_JMP
| BPF_JGE
| BPF_X
:
669 case BPF_JMP
| BPF_JGT
| BPF_K
:
670 case BPF_JMP
| BPF_JGT
| BPF_X
:
671 case BPF_JMP
| BPF_JSET
| BPF_K
:
672 case BPF_JMP
| BPF_JSET
| BPF_X
:
673 /* A jump must set masks on targets */
674 masks
[pc
+ 1 + filter
[pc
].jt
] &= memvalid
;
675 masks
[pc
+ 1 + filter
[pc
].jf
] &= memvalid
;
685 static bool chk_code_allowed(u16 code_to_probe
)
687 static const bool codes
[] = {
688 /* 32 bit ALU operations */
689 [BPF_ALU
| BPF_ADD
| BPF_K
] = true,
690 [BPF_ALU
| BPF_ADD
| BPF_X
] = true,
691 [BPF_ALU
| BPF_SUB
| BPF_K
] = true,
692 [BPF_ALU
| BPF_SUB
| BPF_X
] = true,
693 [BPF_ALU
| BPF_MUL
| BPF_K
] = true,
694 [BPF_ALU
| BPF_MUL
| BPF_X
] = true,
695 [BPF_ALU
| BPF_DIV
| BPF_K
] = true,
696 [BPF_ALU
| BPF_DIV
| BPF_X
] = true,
697 [BPF_ALU
| BPF_MOD
| BPF_K
] = true,
698 [BPF_ALU
| BPF_MOD
| BPF_X
] = true,
699 [BPF_ALU
| BPF_AND
| BPF_K
] = true,
700 [BPF_ALU
| BPF_AND
| BPF_X
] = true,
701 [BPF_ALU
| BPF_OR
| BPF_K
] = true,
702 [BPF_ALU
| BPF_OR
| BPF_X
] = true,
703 [BPF_ALU
| BPF_XOR
| BPF_K
] = true,
704 [BPF_ALU
| BPF_XOR
| BPF_X
] = true,
705 [BPF_ALU
| BPF_LSH
| BPF_K
] = true,
706 [BPF_ALU
| BPF_LSH
| BPF_X
] = true,
707 [BPF_ALU
| BPF_RSH
| BPF_K
] = true,
708 [BPF_ALU
| BPF_RSH
| BPF_X
] = true,
709 [BPF_ALU
| BPF_NEG
] = true,
710 /* Load instructions */
711 [BPF_LD
| BPF_W
| BPF_ABS
] = true,
712 [BPF_LD
| BPF_H
| BPF_ABS
] = true,
713 [BPF_LD
| BPF_B
| BPF_ABS
] = true,
714 [BPF_LD
| BPF_W
| BPF_LEN
] = true,
715 [BPF_LD
| BPF_W
| BPF_IND
] = true,
716 [BPF_LD
| BPF_H
| BPF_IND
] = true,
717 [BPF_LD
| BPF_B
| BPF_IND
] = true,
718 [BPF_LD
| BPF_IMM
] = true,
719 [BPF_LD
| BPF_MEM
] = true,
720 [BPF_LDX
| BPF_W
| BPF_LEN
] = true,
721 [BPF_LDX
| BPF_B
| BPF_MSH
] = true,
722 [BPF_LDX
| BPF_IMM
] = true,
723 [BPF_LDX
| BPF_MEM
] = true,
724 /* Store instructions */
727 /* Misc instructions */
728 [BPF_MISC
| BPF_TAX
] = true,
729 [BPF_MISC
| BPF_TXA
] = true,
730 /* Return instructions */
731 [BPF_RET
| BPF_K
] = true,
732 [BPF_RET
| BPF_A
] = true,
733 /* Jump instructions */
734 [BPF_JMP
| BPF_JA
] = true,
735 [BPF_JMP
| BPF_JEQ
| BPF_K
] = true,
736 [BPF_JMP
| BPF_JEQ
| BPF_X
] = true,
737 [BPF_JMP
| BPF_JGE
| BPF_K
] = true,
738 [BPF_JMP
| BPF_JGE
| BPF_X
] = true,
739 [BPF_JMP
| BPF_JGT
| BPF_K
] = true,
740 [BPF_JMP
| BPF_JGT
| BPF_X
] = true,
741 [BPF_JMP
| BPF_JSET
| BPF_K
] = true,
742 [BPF_JMP
| BPF_JSET
| BPF_X
] = true,
745 if (code_to_probe
>= ARRAY_SIZE(codes
))
748 return codes
[code_to_probe
];
752 * bpf_check_classic - verify socket filter code
753 * @filter: filter to verify
754 * @flen: length of filter
756 * Check the user's filter code. If we let some ugly
757 * filter code slip through kaboom! The filter must contain
758 * no references or jumps that are out of range, no illegal
759 * instructions, and must end with a RET instruction.
761 * All jumps are forward as they are not signed.
763 * Returns 0 if the rule set is legal or -EINVAL if not.
765 static int bpf_check_classic(const struct sock_filter
*filter
,
771 if (flen
== 0 || flen
> BPF_MAXINSNS
)
774 /* Check the filter code now */
775 for (pc
= 0; pc
< flen
; pc
++) {
776 const struct sock_filter
*ftest
= &filter
[pc
];
778 /* May we actually operate on this code? */
779 if (!chk_code_allowed(ftest
->code
))
782 /* Some instructions need special checks */
783 switch (ftest
->code
) {
784 case BPF_ALU
| BPF_DIV
| BPF_K
:
785 case BPF_ALU
| BPF_MOD
| BPF_K
:
786 /* Check for division by zero */
790 case BPF_ALU
| BPF_LSH
| BPF_K
:
791 case BPF_ALU
| BPF_RSH
| BPF_K
:
795 case BPF_LD
| BPF_MEM
:
796 case BPF_LDX
| BPF_MEM
:
799 /* Check for invalid memory addresses */
800 if (ftest
->k
>= BPF_MEMWORDS
)
803 case BPF_JMP
| BPF_JA
:
804 /* Note, the large ftest->k might cause loops.
805 * Compare this with conditional jumps below,
806 * where offsets are limited. --ANK (981016)
808 if (ftest
->k
>= (unsigned int)(flen
- pc
- 1))
811 case BPF_JMP
| BPF_JEQ
| BPF_K
:
812 case BPF_JMP
| BPF_JEQ
| BPF_X
:
813 case BPF_JMP
| BPF_JGE
| BPF_K
:
814 case BPF_JMP
| BPF_JGE
| BPF_X
:
815 case BPF_JMP
| BPF_JGT
| BPF_K
:
816 case BPF_JMP
| BPF_JGT
| BPF_X
:
817 case BPF_JMP
| BPF_JSET
| BPF_K
:
818 case BPF_JMP
| BPF_JSET
| BPF_X
:
819 /* Both conditionals must be safe */
820 if (pc
+ ftest
->jt
+ 1 >= flen
||
821 pc
+ ftest
->jf
+ 1 >= flen
)
824 case BPF_LD
| BPF_W
| BPF_ABS
:
825 case BPF_LD
| BPF_H
| BPF_ABS
:
826 case BPF_LD
| BPF_B
| BPF_ABS
:
828 if (bpf_anc_helper(ftest
) & BPF_ANC
)
830 /* Ancillary operation unknown or unsupported */
831 if (anc_found
== false && ftest
->k
>= SKF_AD_OFF
)
836 /* Last instruction must be a RET code */
837 switch (filter
[flen
- 1].code
) {
838 case BPF_RET
| BPF_K
:
839 case BPF_RET
| BPF_A
:
840 return check_load_and_stores(filter
, flen
);
846 static int bpf_prog_store_orig_filter(struct bpf_prog
*fp
,
847 const struct sock_fprog
*fprog
)
849 unsigned int fsize
= bpf_classic_proglen(fprog
);
850 struct sock_fprog_kern
*fkprog
;
852 fp
->orig_prog
= kmalloc(sizeof(*fkprog
), GFP_KERNEL
);
856 fkprog
= fp
->orig_prog
;
857 fkprog
->len
= fprog
->len
;
859 fkprog
->filter
= kmemdup(fp
->insns
, fsize
,
860 GFP_KERNEL
| __GFP_NOWARN
);
861 if (!fkprog
->filter
) {
862 kfree(fp
->orig_prog
);
869 static void bpf_release_orig_filter(struct bpf_prog
*fp
)
871 struct sock_fprog_kern
*fprog
= fp
->orig_prog
;
874 kfree(fprog
->filter
);
879 static void __bpf_prog_release(struct bpf_prog
*prog
)
881 if (prog
->type
== BPF_PROG_TYPE_SOCKET_FILTER
) {
884 bpf_release_orig_filter(prog
);
889 static void __sk_filter_release(struct sk_filter
*fp
)
891 __bpf_prog_release(fp
->prog
);
896 * sk_filter_release_rcu - Release a socket filter by rcu_head
897 * @rcu: rcu_head that contains the sk_filter to free
899 static void sk_filter_release_rcu(struct rcu_head
*rcu
)
901 struct sk_filter
*fp
= container_of(rcu
, struct sk_filter
, rcu
);
903 __sk_filter_release(fp
);
907 * sk_filter_release - release a socket filter
908 * @fp: filter to remove
910 * Remove a filter from a socket and release its resources.
912 static void sk_filter_release(struct sk_filter
*fp
)
914 if (atomic_dec_and_test(&fp
->refcnt
))
915 call_rcu(&fp
->rcu
, sk_filter_release_rcu
);
918 void sk_filter_uncharge(struct sock
*sk
, struct sk_filter
*fp
)
920 u32 filter_size
= bpf_prog_size(fp
->prog
->len
);
922 atomic_sub(filter_size
, &sk
->sk_omem_alloc
);
923 sk_filter_release(fp
);
926 /* try to charge the socket memory if there is space available
927 * return true on success
929 bool sk_filter_charge(struct sock
*sk
, struct sk_filter
*fp
)
931 u32 filter_size
= bpf_prog_size(fp
->prog
->len
);
933 /* same check as in sock_kmalloc() */
934 if (filter_size
<= sysctl_optmem_max
&&
935 atomic_read(&sk
->sk_omem_alloc
) + filter_size
< sysctl_optmem_max
) {
936 atomic_inc(&fp
->refcnt
);
937 atomic_add(filter_size
, &sk
->sk_omem_alloc
);
943 static struct bpf_prog
*bpf_migrate_filter(struct bpf_prog
*fp
)
945 struct sock_filter
*old_prog
;
946 struct bpf_prog
*old_fp
;
947 int err
, new_len
, old_len
= fp
->len
;
949 /* We are free to overwrite insns et al right here as it
950 * won't be used at this point in time anymore internally
951 * after the migration to the internal BPF instruction
954 BUILD_BUG_ON(sizeof(struct sock_filter
) !=
955 sizeof(struct bpf_insn
));
957 /* Conversion cannot happen on overlapping memory areas,
958 * so we need to keep the user BPF around until the 2nd
959 * pass. At this time, the user BPF is stored in fp->insns.
961 old_prog
= kmemdup(fp
->insns
, old_len
* sizeof(struct sock_filter
),
962 GFP_KERNEL
| __GFP_NOWARN
);
968 /* 1st pass: calculate the new program length. */
969 err
= bpf_convert_filter(old_prog
, old_len
, NULL
, &new_len
);
973 /* Expand fp for appending the new filter representation. */
975 fp
= bpf_prog_realloc(old_fp
, bpf_prog_size(new_len
), 0);
977 /* The old_fp is still around in case we couldn't
978 * allocate new memory, so uncharge on that one.
987 /* 2nd pass: remap sock_filter insns into bpf_insn insns. */
988 err
= bpf_convert_filter(old_prog
, old_len
, fp
->insnsi
, &new_len
);
990 /* 2nd bpf_convert_filter() can fail only if it fails
991 * to allocate memory, remapping must succeed. Note,
992 * that at this time old_fp has already been released
997 bpf_prog_select_runtime(fp
);
1005 __bpf_prog_release(fp
);
1006 return ERR_PTR(err
);
1009 static struct bpf_prog
*bpf_prepare_filter(struct bpf_prog
*fp
,
1010 bpf_aux_classic_check_t trans
)
1014 fp
->bpf_func
= NULL
;
1017 err
= bpf_check_classic(fp
->insns
, fp
->len
);
1019 __bpf_prog_release(fp
);
1020 return ERR_PTR(err
);
1023 /* There might be additional checks and transformations
1024 * needed on classic filters, f.e. in case of seccomp.
1027 err
= trans(fp
->insns
, fp
->len
);
1029 __bpf_prog_release(fp
);
1030 return ERR_PTR(err
);
1034 /* Probe if we can JIT compile the filter and if so, do
1035 * the compilation of the filter.
1037 bpf_jit_compile(fp
);
1039 /* JIT compiler couldn't process this filter, so do the
1040 * internal BPF translation for the optimized interpreter.
1043 fp
= bpf_migrate_filter(fp
);
1049 * bpf_prog_create - create an unattached filter
1050 * @pfp: the unattached filter that is created
1051 * @fprog: the filter program
1053 * Create a filter independent of any socket. We first run some
1054 * sanity checks on it to make sure it does not explode on us later.
1055 * If an error occurs or there is insufficient memory for the filter
1056 * a negative errno code is returned. On success the return is zero.
1058 int bpf_prog_create(struct bpf_prog
**pfp
, struct sock_fprog_kern
*fprog
)
1060 unsigned int fsize
= bpf_classic_proglen(fprog
);
1061 struct bpf_prog
*fp
;
1063 /* Make sure new filter is there and in the right amounts. */
1064 if (fprog
->filter
== NULL
)
1067 fp
= bpf_prog_alloc(bpf_prog_size(fprog
->len
), 0);
1071 memcpy(fp
->insns
, fprog
->filter
, fsize
);
1073 fp
->len
= fprog
->len
;
1074 /* Since unattached filters are not copied back to user
1075 * space through sk_get_filter(), we do not need to hold
1076 * a copy here, and can spare us the work.
1078 fp
->orig_prog
= NULL
;
1080 /* bpf_prepare_filter() already takes care of freeing
1081 * memory in case something goes wrong.
1083 fp
= bpf_prepare_filter(fp
, NULL
);
1090 EXPORT_SYMBOL_GPL(bpf_prog_create
);
1093 * bpf_prog_create_from_user - create an unattached filter from user buffer
1094 * @pfp: the unattached filter that is created
1095 * @fprog: the filter program
1096 * @trans: post-classic verifier transformation handler
1097 * @save_orig: save classic BPF program
1099 * This function effectively does the same as bpf_prog_create(), only
1100 * that it builds up its insns buffer from user space provided buffer.
1101 * It also allows for passing a bpf_aux_classic_check_t handler.
1103 int bpf_prog_create_from_user(struct bpf_prog
**pfp
, struct sock_fprog
*fprog
,
1104 bpf_aux_classic_check_t trans
, bool save_orig
)
1106 unsigned int fsize
= bpf_classic_proglen(fprog
);
1107 struct bpf_prog
*fp
;
1110 /* Make sure new filter is there and in the right amounts. */
1111 if (fprog
->filter
== NULL
)
1114 fp
= bpf_prog_alloc(bpf_prog_size(fprog
->len
), 0);
1118 if (copy_from_user(fp
->insns
, fprog
->filter
, fsize
)) {
1119 __bpf_prog_free(fp
);
1123 fp
->len
= fprog
->len
;
1124 fp
->orig_prog
= NULL
;
1127 err
= bpf_prog_store_orig_filter(fp
, fprog
);
1129 __bpf_prog_free(fp
);
1134 /* bpf_prepare_filter() already takes care of freeing
1135 * memory in case something goes wrong.
1137 fp
= bpf_prepare_filter(fp
, trans
);
1144 EXPORT_SYMBOL_GPL(bpf_prog_create_from_user
);
1146 void bpf_prog_destroy(struct bpf_prog
*fp
)
1148 __bpf_prog_release(fp
);
1150 EXPORT_SYMBOL_GPL(bpf_prog_destroy
);
1152 static int __sk_attach_prog(struct bpf_prog
*prog
, struct sock
*sk
,
1155 struct sk_filter
*fp
, *old_fp
;
1157 fp
= kmalloc(sizeof(*fp
), GFP_KERNEL
);
1162 atomic_set(&fp
->refcnt
, 0);
1164 if (!sk_filter_charge(sk
, fp
)) {
1169 old_fp
= rcu_dereference_protected(sk
->sk_filter
, locked
);
1170 rcu_assign_pointer(sk
->sk_filter
, fp
);
1172 sk_filter_uncharge(sk
, old_fp
);
1177 static int __reuseport_attach_prog(struct bpf_prog
*prog
, struct sock
*sk
)
1179 struct bpf_prog
*old_prog
;
1182 if (bpf_prog_size(prog
->len
) > sysctl_optmem_max
)
1185 if (sk_unhashed(sk
) && sk
->sk_reuseport
) {
1186 err
= reuseport_alloc(sk
);
1189 } else if (!rcu_access_pointer(sk
->sk_reuseport_cb
)) {
1190 /* The socket wasn't bound with SO_REUSEPORT */
1194 old_prog
= reuseport_attach_prog(sk
, prog
);
1196 bpf_prog_destroy(old_prog
);
1202 struct bpf_prog
*__get_filter(struct sock_fprog
*fprog
, struct sock
*sk
)
1204 unsigned int fsize
= bpf_classic_proglen(fprog
);
1205 unsigned int bpf_fsize
= bpf_prog_size(fprog
->len
);
1206 struct bpf_prog
*prog
;
1209 if (sock_flag(sk
, SOCK_FILTER_LOCKED
))
1210 return ERR_PTR(-EPERM
);
1212 /* Make sure new filter is there and in the right amounts. */
1213 if (fprog
->filter
== NULL
)
1214 return ERR_PTR(-EINVAL
);
1216 prog
= bpf_prog_alloc(bpf_fsize
, 0);
1218 return ERR_PTR(-ENOMEM
);
1220 if (copy_from_user(prog
->insns
, fprog
->filter
, fsize
)) {
1221 __bpf_prog_free(prog
);
1222 return ERR_PTR(-EFAULT
);
1225 prog
->len
= fprog
->len
;
1227 err
= bpf_prog_store_orig_filter(prog
, fprog
);
1229 __bpf_prog_free(prog
);
1230 return ERR_PTR(-ENOMEM
);
1233 /* bpf_prepare_filter() already takes care of freeing
1234 * memory in case something goes wrong.
1236 return bpf_prepare_filter(prog
, NULL
);
1240 * sk_attach_filter - attach a socket filter
1241 * @fprog: the filter program
1242 * @sk: the socket to use
1244 * Attach the user's filter code. We first run some sanity checks on
1245 * it to make sure it does not explode on us later. If an error
1246 * occurs or there is insufficient memory for the filter a negative
1247 * errno code is returned. On success the return is zero.
1249 int __sk_attach_filter(struct sock_fprog
*fprog
, struct sock
*sk
,
1252 struct bpf_prog
*prog
= __get_filter(fprog
, sk
);
1256 return PTR_ERR(prog
);
1258 err
= __sk_attach_prog(prog
, sk
, locked
);
1260 __bpf_prog_release(prog
);
1266 EXPORT_SYMBOL_GPL(__sk_attach_filter
);
1268 int sk_attach_filter(struct sock_fprog
*fprog
, struct sock
*sk
)
1270 return __sk_attach_filter(fprog
, sk
, sock_owned_by_user(sk
));
1273 int sk_reuseport_attach_filter(struct sock_fprog
*fprog
, struct sock
*sk
)
1275 struct bpf_prog
*prog
= __get_filter(fprog
, sk
);
1279 return PTR_ERR(prog
);
1281 err
= __reuseport_attach_prog(prog
, sk
);
1283 __bpf_prog_release(prog
);
1290 static struct bpf_prog
*__get_bpf(u32 ufd
, struct sock
*sk
)
1292 struct bpf_prog
*prog
;
1294 if (sock_flag(sk
, SOCK_FILTER_LOCKED
))
1295 return ERR_PTR(-EPERM
);
1297 prog
= bpf_prog_get(ufd
);
1301 if (prog
->type
!= BPF_PROG_TYPE_SOCKET_FILTER
) {
1303 return ERR_PTR(-EINVAL
);
1309 int sk_attach_bpf(u32 ufd
, struct sock
*sk
)
1311 struct bpf_prog
*prog
= __get_bpf(ufd
, sk
);
1315 return PTR_ERR(prog
);
1317 err
= __sk_attach_prog(prog
, sk
, sock_owned_by_user(sk
));
1326 int sk_reuseport_attach_bpf(u32 ufd
, struct sock
*sk
)
1328 struct bpf_prog
*prog
= __get_bpf(ufd
, sk
);
1332 return PTR_ERR(prog
);
1334 err
= __reuseport_attach_prog(prog
, sk
);
1343 struct bpf_scratchpad
{
1345 __be32 diff
[MAX_BPF_STACK
/ sizeof(__be32
)];
1346 u8 buff
[MAX_BPF_STACK
];
1350 static DEFINE_PER_CPU(struct bpf_scratchpad
, bpf_sp
);
1352 static u64
bpf_skb_store_bytes(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 flags
)
1354 struct bpf_scratchpad
*sp
= this_cpu_ptr(&bpf_sp
);
1355 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1356 int offset
= (int) r2
;
1357 void *from
= (void *) (long) r3
;
1358 unsigned int len
= (unsigned int) r4
;
1361 if (unlikely(flags
& ~(BPF_F_RECOMPUTE_CSUM
| BPF_F_INVALIDATE_HASH
)))
1364 /* bpf verifier guarantees that:
1365 * 'from' pointer points to bpf program stack
1366 * 'len' bytes of it were initialized
1368 * 'skb' is a valid pointer to 'struct sk_buff'
1370 * so check for invalid 'offset' and too large 'len'
1372 if (unlikely((u32
) offset
> 0xffff || len
> sizeof(sp
->buff
)))
1374 if (unlikely(skb_try_make_writable(skb
, offset
+ len
)))
1377 ptr
= skb_header_pointer(skb
, offset
, len
, sp
->buff
);
1381 if (flags
& BPF_F_RECOMPUTE_CSUM
)
1382 skb_postpull_rcsum(skb
, ptr
, len
);
1384 memcpy(ptr
, from
, len
);
1386 if (ptr
== sp
->buff
)
1387 /* skb_store_bits cannot return -EFAULT here */
1388 skb_store_bits(skb
, offset
, ptr
, len
);
1390 if (flags
& BPF_F_RECOMPUTE_CSUM
)
1391 skb_postpush_rcsum(skb
, ptr
, len
);
1392 if (flags
& BPF_F_INVALIDATE_HASH
)
1393 skb_clear_hash(skb
);
1398 static const struct bpf_func_proto bpf_skb_store_bytes_proto
= {
1399 .func
= bpf_skb_store_bytes
,
1401 .ret_type
= RET_INTEGER
,
1402 .arg1_type
= ARG_PTR_TO_CTX
,
1403 .arg2_type
= ARG_ANYTHING
,
1404 .arg3_type
= ARG_PTR_TO_STACK
,
1405 .arg4_type
= ARG_CONST_STACK_SIZE
,
1406 .arg5_type
= ARG_ANYTHING
,
1409 static u64
bpf_skb_load_bytes(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
1411 const struct sk_buff
*skb
= (const struct sk_buff
*)(unsigned long) r1
;
1412 int offset
= (int) r2
;
1413 void *to
= (void *)(unsigned long) r3
;
1414 unsigned int len
= (unsigned int) r4
;
1417 if (unlikely((u32
) offset
> 0xffff || len
> MAX_BPF_STACK
))
1420 ptr
= skb_header_pointer(skb
, offset
, len
, to
);
1424 memcpy(to
, ptr
, len
);
1429 static const struct bpf_func_proto bpf_skb_load_bytes_proto
= {
1430 .func
= bpf_skb_load_bytes
,
1432 .ret_type
= RET_INTEGER
,
1433 .arg1_type
= ARG_PTR_TO_CTX
,
1434 .arg2_type
= ARG_ANYTHING
,
1435 .arg3_type
= ARG_PTR_TO_STACK
,
1436 .arg4_type
= ARG_CONST_STACK_SIZE
,
1439 static u64
bpf_l3_csum_replace(u64 r1
, u64 r2
, u64 from
, u64 to
, u64 flags
)
1441 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1442 int offset
= (int) r2
;
1445 if (unlikely(flags
& ~(BPF_F_HDR_FIELD_MASK
)))
1447 if (unlikely((u32
) offset
> 0xffff))
1449 if (unlikely(skb_try_make_writable(skb
, offset
+ sizeof(sum
))))
1452 ptr
= skb_header_pointer(skb
, offset
, sizeof(sum
), &sum
);
1456 switch (flags
& BPF_F_HDR_FIELD_MASK
) {
1458 if (unlikely(from
!= 0))
1461 csum_replace_by_diff(ptr
, to
);
1464 csum_replace2(ptr
, from
, to
);
1467 csum_replace4(ptr
, from
, to
);
1474 /* skb_store_bits guaranteed to not return -EFAULT here */
1475 skb_store_bits(skb
, offset
, ptr
, sizeof(sum
));
1480 static const struct bpf_func_proto bpf_l3_csum_replace_proto
= {
1481 .func
= bpf_l3_csum_replace
,
1483 .ret_type
= RET_INTEGER
,
1484 .arg1_type
= ARG_PTR_TO_CTX
,
1485 .arg2_type
= ARG_ANYTHING
,
1486 .arg3_type
= ARG_ANYTHING
,
1487 .arg4_type
= ARG_ANYTHING
,
1488 .arg5_type
= ARG_ANYTHING
,
1491 static u64
bpf_l4_csum_replace(u64 r1
, u64 r2
, u64 from
, u64 to
, u64 flags
)
1493 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1494 bool is_pseudo
= flags
& BPF_F_PSEUDO_HDR
;
1495 bool is_mmzero
= flags
& BPF_F_MARK_MANGLED_0
;
1496 int offset
= (int) r2
;
1499 if (unlikely(flags
& ~(BPF_F_MARK_MANGLED_0
| BPF_F_PSEUDO_HDR
|
1500 BPF_F_HDR_FIELD_MASK
)))
1502 if (unlikely((u32
) offset
> 0xffff))
1504 if (unlikely(skb_try_make_writable(skb
, offset
+ sizeof(sum
))))
1507 ptr
= skb_header_pointer(skb
, offset
, sizeof(sum
), &sum
);
1510 if (is_mmzero
&& !*ptr
)
1513 switch (flags
& BPF_F_HDR_FIELD_MASK
) {
1515 if (unlikely(from
!= 0))
1518 inet_proto_csum_replace_by_diff(ptr
, skb
, to
, is_pseudo
);
1521 inet_proto_csum_replace2(ptr
, skb
, from
, to
, is_pseudo
);
1524 inet_proto_csum_replace4(ptr
, skb
, from
, to
, is_pseudo
);
1530 if (is_mmzero
&& !*ptr
)
1531 *ptr
= CSUM_MANGLED_0
;
1533 /* skb_store_bits guaranteed to not return -EFAULT here */
1534 skb_store_bits(skb
, offset
, ptr
, sizeof(sum
));
1539 static const struct bpf_func_proto bpf_l4_csum_replace_proto
= {
1540 .func
= bpf_l4_csum_replace
,
1542 .ret_type
= RET_INTEGER
,
1543 .arg1_type
= ARG_PTR_TO_CTX
,
1544 .arg2_type
= ARG_ANYTHING
,
1545 .arg3_type
= ARG_ANYTHING
,
1546 .arg4_type
= ARG_ANYTHING
,
1547 .arg5_type
= ARG_ANYTHING
,
1550 static u64
bpf_csum_diff(u64 r1
, u64 from_size
, u64 r3
, u64 to_size
, u64 seed
)
1552 struct bpf_scratchpad
*sp
= this_cpu_ptr(&bpf_sp
);
1553 u64 diff_size
= from_size
+ to_size
;
1554 __be32
*from
= (__be32
*) (long) r1
;
1555 __be32
*to
= (__be32
*) (long) r3
;
1558 /* This is quite flexible, some examples:
1560 * from_size == 0, to_size > 0, seed := csum --> pushing data
1561 * from_size > 0, to_size == 0, seed := csum --> pulling data
1562 * from_size > 0, to_size > 0, seed := 0 --> diffing data
1564 * Even for diffing, from_size and to_size don't need to be equal.
1566 if (unlikely(((from_size
| to_size
) & (sizeof(__be32
) - 1)) ||
1567 diff_size
> sizeof(sp
->diff
)))
1570 for (i
= 0; i
< from_size
/ sizeof(__be32
); i
++, j
++)
1571 sp
->diff
[j
] = ~from
[i
];
1572 for (i
= 0; i
< to_size
/ sizeof(__be32
); i
++, j
++)
1573 sp
->diff
[j
] = to
[i
];
1575 return csum_partial(sp
->diff
, diff_size
, seed
);
1578 static const struct bpf_func_proto bpf_csum_diff_proto
= {
1579 .func
= bpf_csum_diff
,
1581 .ret_type
= RET_INTEGER
,
1582 .arg1_type
= ARG_PTR_TO_STACK
,
1583 .arg2_type
= ARG_CONST_STACK_SIZE_OR_ZERO
,
1584 .arg3_type
= ARG_PTR_TO_STACK
,
1585 .arg4_type
= ARG_CONST_STACK_SIZE_OR_ZERO
,
1586 .arg5_type
= ARG_ANYTHING
,
1589 static u64
bpf_clone_redirect(u64 r1
, u64 ifindex
, u64 flags
, u64 r4
, u64 r5
)
1591 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
, *skb2
;
1592 struct net_device
*dev
;
1594 if (unlikely(flags
& ~(BPF_F_INGRESS
)))
1597 dev
= dev_get_by_index_rcu(dev_net(skb
->dev
), ifindex
);
1601 skb2
= skb_clone(skb
, GFP_ATOMIC
);
1602 if (unlikely(!skb2
))
1605 if (flags
& BPF_F_INGRESS
) {
1606 if (skb_at_tc_ingress(skb2
))
1607 skb_postpush_rcsum(skb2
, skb_mac_header(skb2
),
1609 return dev_forward_skb(dev
, skb2
);
1613 return dev_queue_xmit(skb2
);
1616 static const struct bpf_func_proto bpf_clone_redirect_proto
= {
1617 .func
= bpf_clone_redirect
,
1619 .ret_type
= RET_INTEGER
,
1620 .arg1_type
= ARG_PTR_TO_CTX
,
1621 .arg2_type
= ARG_ANYTHING
,
1622 .arg3_type
= ARG_ANYTHING
,
1625 struct redirect_info
{
1630 static DEFINE_PER_CPU(struct redirect_info
, redirect_info
);
1632 static u64
bpf_redirect(u64 ifindex
, u64 flags
, u64 r3
, u64 r4
, u64 r5
)
1634 struct redirect_info
*ri
= this_cpu_ptr(&redirect_info
);
1636 if (unlikely(flags
& ~(BPF_F_INGRESS
)))
1639 ri
->ifindex
= ifindex
;
1642 return TC_ACT_REDIRECT
;
1645 int skb_do_redirect(struct sk_buff
*skb
)
1647 struct redirect_info
*ri
= this_cpu_ptr(&redirect_info
);
1648 struct net_device
*dev
;
1650 dev
= dev_get_by_index_rcu(dev_net(skb
->dev
), ri
->ifindex
);
1652 if (unlikely(!dev
)) {
1657 if (ri
->flags
& BPF_F_INGRESS
) {
1658 if (skb_at_tc_ingress(skb
))
1659 skb_postpush_rcsum(skb
, skb_mac_header(skb
),
1661 return dev_forward_skb(dev
, skb
);
1665 return dev_queue_xmit(skb
);
1668 static const struct bpf_func_proto bpf_redirect_proto
= {
1669 .func
= bpf_redirect
,
1671 .ret_type
= RET_INTEGER
,
1672 .arg1_type
= ARG_ANYTHING
,
1673 .arg2_type
= ARG_ANYTHING
,
1676 static u64
bpf_get_cgroup_classid(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
1678 return task_get_classid((struct sk_buff
*) (unsigned long) r1
);
1681 static const struct bpf_func_proto bpf_get_cgroup_classid_proto
= {
1682 .func
= bpf_get_cgroup_classid
,
1684 .ret_type
= RET_INTEGER
,
1685 .arg1_type
= ARG_PTR_TO_CTX
,
1688 static u64
bpf_get_route_realm(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
1690 return dst_tclassid((struct sk_buff
*) (unsigned long) r1
);
1693 static const struct bpf_func_proto bpf_get_route_realm_proto
= {
1694 .func
= bpf_get_route_realm
,
1696 .ret_type
= RET_INTEGER
,
1697 .arg1_type
= ARG_PTR_TO_CTX
,
1700 static u64
bpf_skb_vlan_push(u64 r1
, u64 r2
, u64 vlan_tci
, u64 r4
, u64 r5
)
1702 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1703 __be16 vlan_proto
= (__force __be16
) r2
;
1705 if (unlikely(vlan_proto
!= htons(ETH_P_8021Q
) &&
1706 vlan_proto
!= htons(ETH_P_8021AD
)))
1707 vlan_proto
= htons(ETH_P_8021Q
);
1709 return skb_vlan_push(skb
, vlan_proto
, vlan_tci
);
1712 const struct bpf_func_proto bpf_skb_vlan_push_proto
= {
1713 .func
= bpf_skb_vlan_push
,
1715 .ret_type
= RET_INTEGER
,
1716 .arg1_type
= ARG_PTR_TO_CTX
,
1717 .arg2_type
= ARG_ANYTHING
,
1718 .arg3_type
= ARG_ANYTHING
,
1720 EXPORT_SYMBOL_GPL(bpf_skb_vlan_push_proto
);
1722 static u64
bpf_skb_vlan_pop(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
1724 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1726 return skb_vlan_pop(skb
);
1729 const struct bpf_func_proto bpf_skb_vlan_pop_proto
= {
1730 .func
= bpf_skb_vlan_pop
,
1732 .ret_type
= RET_INTEGER
,
1733 .arg1_type
= ARG_PTR_TO_CTX
,
1735 EXPORT_SYMBOL_GPL(bpf_skb_vlan_pop_proto
);
1737 bool bpf_helper_changes_skb_data(void *func
)
1739 if (func
== bpf_skb_vlan_push
)
1741 if (func
== bpf_skb_vlan_pop
)
1743 if (func
== bpf_skb_store_bytes
)
1745 if (func
== bpf_l3_csum_replace
)
1747 if (func
== bpf_l4_csum_replace
)
1753 static unsigned short bpf_tunnel_key_af(u64 flags
)
1755 return flags
& BPF_F_TUNINFO_IPV6
? AF_INET6
: AF_INET
;
1758 static u64
bpf_skb_get_tunnel_key(u64 r1
, u64 r2
, u64 size
, u64 flags
, u64 r5
)
1760 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1761 struct bpf_tunnel_key
*to
= (struct bpf_tunnel_key
*) (long) r2
;
1762 const struct ip_tunnel_info
*info
= skb_tunnel_info(skb
);
1763 u8 compat
[sizeof(struct bpf_tunnel_key
)];
1765 if (unlikely(!info
|| (flags
& ~(BPF_F_TUNINFO_IPV6
))))
1767 if (ip_tunnel_info_af(info
) != bpf_tunnel_key_af(flags
))
1769 if (unlikely(size
!= sizeof(struct bpf_tunnel_key
))) {
1771 case offsetof(struct bpf_tunnel_key
, tunnel_label
):
1772 case offsetof(struct bpf_tunnel_key
, tunnel_ext
):
1774 case offsetof(struct bpf_tunnel_key
, remote_ipv6
[1]):
1775 /* Fixup deprecated structure layouts here, so we have
1776 * a common path later on.
1778 if (ip_tunnel_info_af(info
) != AF_INET
)
1781 to
= (struct bpf_tunnel_key
*)compat
;
1788 to
->tunnel_id
= be64_to_cpu(info
->key
.tun_id
);
1789 to
->tunnel_tos
= info
->key
.tos
;
1790 to
->tunnel_ttl
= info
->key
.ttl
;
1792 if (flags
& BPF_F_TUNINFO_IPV6
) {
1793 memcpy(to
->remote_ipv6
, &info
->key
.u
.ipv6
.src
,
1794 sizeof(to
->remote_ipv6
));
1795 to
->tunnel_label
= be32_to_cpu(info
->key
.label
);
1797 to
->remote_ipv4
= be32_to_cpu(info
->key
.u
.ipv4
.src
);
1800 if (unlikely(size
!= sizeof(struct bpf_tunnel_key
)))
1801 memcpy((void *)(long) r2
, to
, size
);
1806 static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto
= {
1807 .func
= bpf_skb_get_tunnel_key
,
1809 .ret_type
= RET_INTEGER
,
1810 .arg1_type
= ARG_PTR_TO_CTX
,
1811 .arg2_type
= ARG_PTR_TO_STACK
,
1812 .arg3_type
= ARG_CONST_STACK_SIZE
,
1813 .arg4_type
= ARG_ANYTHING
,
1816 static u64
bpf_skb_get_tunnel_opt(u64 r1
, u64 r2
, u64 size
, u64 r4
, u64 r5
)
1818 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1819 u8
*to
= (u8
*) (long) r2
;
1820 const struct ip_tunnel_info
*info
= skb_tunnel_info(skb
);
1822 if (unlikely(!info
||
1823 !(info
->key
.tun_flags
& TUNNEL_OPTIONS_PRESENT
)))
1825 if (unlikely(size
< info
->options_len
))
1828 ip_tunnel_info_opts_get(to
, info
);
1830 return info
->options_len
;
1833 static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto
= {
1834 .func
= bpf_skb_get_tunnel_opt
,
1836 .ret_type
= RET_INTEGER
,
1837 .arg1_type
= ARG_PTR_TO_CTX
,
1838 .arg2_type
= ARG_PTR_TO_STACK
,
1839 .arg3_type
= ARG_CONST_STACK_SIZE
,
1842 static struct metadata_dst __percpu
*md_dst
;
1844 static u64
bpf_skb_set_tunnel_key(u64 r1
, u64 r2
, u64 size
, u64 flags
, u64 r5
)
1846 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1847 struct bpf_tunnel_key
*from
= (struct bpf_tunnel_key
*) (long) r2
;
1848 struct metadata_dst
*md
= this_cpu_ptr(md_dst
);
1849 u8 compat
[sizeof(struct bpf_tunnel_key
)];
1850 struct ip_tunnel_info
*info
;
1852 if (unlikely(flags
& ~(BPF_F_TUNINFO_IPV6
| BPF_F_ZERO_CSUM_TX
|
1853 BPF_F_DONT_FRAGMENT
)))
1855 if (unlikely(size
!= sizeof(struct bpf_tunnel_key
))) {
1857 case offsetof(struct bpf_tunnel_key
, tunnel_label
):
1858 case offsetof(struct bpf_tunnel_key
, tunnel_ext
):
1859 case offsetof(struct bpf_tunnel_key
, remote_ipv6
[1]):
1860 /* Fixup deprecated structure layouts here, so we have
1861 * a common path later on.
1863 memcpy(compat
, from
, size
);
1864 memset(compat
+ size
, 0, sizeof(compat
) - size
);
1865 from
= (struct bpf_tunnel_key
*)compat
;
1871 if (unlikely((!(flags
& BPF_F_TUNINFO_IPV6
) && from
->tunnel_label
) ||
1876 dst_hold((struct dst_entry
*) md
);
1877 skb_dst_set(skb
, (struct dst_entry
*) md
);
1879 info
= &md
->u
.tun_info
;
1880 info
->mode
= IP_TUNNEL_INFO_TX
;
1882 info
->key
.tun_flags
= TUNNEL_KEY
| TUNNEL_CSUM
| TUNNEL_NOCACHE
;
1883 if (flags
& BPF_F_DONT_FRAGMENT
)
1884 info
->key
.tun_flags
|= TUNNEL_DONT_FRAGMENT
;
1886 info
->key
.tun_id
= cpu_to_be64(from
->tunnel_id
);
1887 info
->key
.tos
= from
->tunnel_tos
;
1888 info
->key
.ttl
= from
->tunnel_ttl
;
1890 if (flags
& BPF_F_TUNINFO_IPV6
) {
1891 info
->mode
|= IP_TUNNEL_INFO_IPV6
;
1892 memcpy(&info
->key
.u
.ipv6
.dst
, from
->remote_ipv6
,
1893 sizeof(from
->remote_ipv6
));
1894 info
->key
.label
= cpu_to_be32(from
->tunnel_label
) &
1895 IPV6_FLOWLABEL_MASK
;
1897 info
->key
.u
.ipv4
.dst
= cpu_to_be32(from
->remote_ipv4
);
1898 if (flags
& BPF_F_ZERO_CSUM_TX
)
1899 info
->key
.tun_flags
&= ~TUNNEL_CSUM
;
1905 static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto
= {
1906 .func
= bpf_skb_set_tunnel_key
,
1908 .ret_type
= RET_INTEGER
,
1909 .arg1_type
= ARG_PTR_TO_CTX
,
1910 .arg2_type
= ARG_PTR_TO_STACK
,
1911 .arg3_type
= ARG_CONST_STACK_SIZE
,
1912 .arg4_type
= ARG_ANYTHING
,
1915 static u64
bpf_skb_set_tunnel_opt(u64 r1
, u64 r2
, u64 size
, u64 r4
, u64 r5
)
1917 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1918 u8
*from
= (u8
*) (long) r2
;
1919 struct ip_tunnel_info
*info
= skb_tunnel_info(skb
);
1920 const struct metadata_dst
*md
= this_cpu_ptr(md_dst
);
1922 if (unlikely(info
!= &md
->u
.tun_info
|| (size
& (sizeof(u32
) - 1))))
1924 if (unlikely(size
> IP_TUNNEL_OPTS_MAX
))
1927 ip_tunnel_info_opts_set(info
, from
, size
);
1932 static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto
= {
1933 .func
= bpf_skb_set_tunnel_opt
,
1935 .ret_type
= RET_INTEGER
,
1936 .arg1_type
= ARG_PTR_TO_CTX
,
1937 .arg2_type
= ARG_PTR_TO_STACK
,
1938 .arg3_type
= ARG_CONST_STACK_SIZE
,
1941 static const struct bpf_func_proto
*
1942 bpf_get_skb_set_tunnel_proto(enum bpf_func_id which
)
1945 /* Race is not possible, since it's called from verifier
1946 * that is holding verifier mutex.
1948 md_dst
= metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX
,
1955 case BPF_FUNC_skb_set_tunnel_key
:
1956 return &bpf_skb_set_tunnel_key_proto
;
1957 case BPF_FUNC_skb_set_tunnel_opt
:
1958 return &bpf_skb_set_tunnel_opt_proto
;
1964 static const struct bpf_func_proto
*
1965 sk_filter_func_proto(enum bpf_func_id func_id
)
1968 case BPF_FUNC_map_lookup_elem
:
1969 return &bpf_map_lookup_elem_proto
;
1970 case BPF_FUNC_map_update_elem
:
1971 return &bpf_map_update_elem_proto
;
1972 case BPF_FUNC_map_delete_elem
:
1973 return &bpf_map_delete_elem_proto
;
1974 case BPF_FUNC_get_prandom_u32
:
1975 return &bpf_get_prandom_u32_proto
;
1976 case BPF_FUNC_get_smp_processor_id
:
1977 return &bpf_get_smp_processor_id_proto
;
1978 case BPF_FUNC_tail_call
:
1979 return &bpf_tail_call_proto
;
1980 case BPF_FUNC_ktime_get_ns
:
1981 return &bpf_ktime_get_ns_proto
;
1982 case BPF_FUNC_trace_printk
:
1983 if (capable(CAP_SYS_ADMIN
))
1984 return bpf_get_trace_printk_proto();
1990 static const struct bpf_func_proto
*
1991 tc_cls_act_func_proto(enum bpf_func_id func_id
)
1994 case BPF_FUNC_skb_store_bytes
:
1995 return &bpf_skb_store_bytes_proto
;
1996 case BPF_FUNC_skb_load_bytes
:
1997 return &bpf_skb_load_bytes_proto
;
1998 case BPF_FUNC_csum_diff
:
1999 return &bpf_csum_diff_proto
;
2000 case BPF_FUNC_l3_csum_replace
:
2001 return &bpf_l3_csum_replace_proto
;
2002 case BPF_FUNC_l4_csum_replace
:
2003 return &bpf_l4_csum_replace_proto
;
2004 case BPF_FUNC_clone_redirect
:
2005 return &bpf_clone_redirect_proto
;
2006 case BPF_FUNC_get_cgroup_classid
:
2007 return &bpf_get_cgroup_classid_proto
;
2008 case BPF_FUNC_skb_vlan_push
:
2009 return &bpf_skb_vlan_push_proto
;
2010 case BPF_FUNC_skb_vlan_pop
:
2011 return &bpf_skb_vlan_pop_proto
;
2012 case BPF_FUNC_skb_get_tunnel_key
:
2013 return &bpf_skb_get_tunnel_key_proto
;
2014 case BPF_FUNC_skb_set_tunnel_key
:
2015 return bpf_get_skb_set_tunnel_proto(func_id
);
2016 case BPF_FUNC_skb_get_tunnel_opt
:
2017 return &bpf_skb_get_tunnel_opt_proto
;
2018 case BPF_FUNC_skb_set_tunnel_opt
:
2019 return bpf_get_skb_set_tunnel_proto(func_id
);
2020 case BPF_FUNC_redirect
:
2021 return &bpf_redirect_proto
;
2022 case BPF_FUNC_get_route_realm
:
2023 return &bpf_get_route_realm_proto
;
2025 return sk_filter_func_proto(func_id
);
2029 static bool __is_valid_access(int off
, int size
, enum bpf_access_type type
)
2032 if (off
< 0 || off
>= sizeof(struct __sk_buff
))
2035 /* disallow misaligned access */
2036 if (off
% size
!= 0)
2039 /* all __sk_buff fields are __u32 */
2046 static bool sk_filter_is_valid_access(int off
, int size
,
2047 enum bpf_access_type type
)
2049 if (off
== offsetof(struct __sk_buff
, tc_classid
))
2052 if (type
== BPF_WRITE
) {
2054 case offsetof(struct __sk_buff
, cb
[0]) ...
2055 offsetof(struct __sk_buff
, cb
[4]):
2062 return __is_valid_access(off
, size
, type
);
2065 static bool tc_cls_act_is_valid_access(int off
, int size
,
2066 enum bpf_access_type type
)
2068 if (type
== BPF_WRITE
) {
2070 case offsetof(struct __sk_buff
, mark
):
2071 case offsetof(struct __sk_buff
, tc_index
):
2072 case offsetof(struct __sk_buff
, priority
):
2073 case offsetof(struct __sk_buff
, cb
[0]) ...
2074 offsetof(struct __sk_buff
, cb
[4]):
2075 case offsetof(struct __sk_buff
, tc_classid
):
2081 return __is_valid_access(off
, size
, type
);
2084 static u32
bpf_net_convert_ctx_access(enum bpf_access_type type
, int dst_reg
,
2085 int src_reg
, int ctx_off
,
2086 struct bpf_insn
*insn_buf
,
2087 struct bpf_prog
*prog
)
2089 struct bpf_insn
*insn
= insn_buf
;
2092 case offsetof(struct __sk_buff
, len
):
2093 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, len
) != 4);
2095 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2096 offsetof(struct sk_buff
, len
));
2099 case offsetof(struct __sk_buff
, protocol
):
2100 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, protocol
) != 2);
2102 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
2103 offsetof(struct sk_buff
, protocol
));
2106 case offsetof(struct __sk_buff
, vlan_proto
):
2107 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, vlan_proto
) != 2);
2109 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
2110 offsetof(struct sk_buff
, vlan_proto
));
2113 case offsetof(struct __sk_buff
, priority
):
2114 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, priority
) != 4);
2116 if (type
== BPF_WRITE
)
2117 *insn
++ = BPF_STX_MEM(BPF_W
, dst_reg
, src_reg
,
2118 offsetof(struct sk_buff
, priority
));
2120 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2121 offsetof(struct sk_buff
, priority
));
2124 case offsetof(struct __sk_buff
, ingress_ifindex
):
2125 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, skb_iif
) != 4);
2127 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2128 offsetof(struct sk_buff
, skb_iif
));
2131 case offsetof(struct __sk_buff
, ifindex
):
2132 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device
, ifindex
) != 4);
2134 *insn
++ = BPF_LDX_MEM(bytes_to_bpf_size(FIELD_SIZEOF(struct sk_buff
, dev
)),
2136 offsetof(struct sk_buff
, dev
));
2137 *insn
++ = BPF_JMP_IMM(BPF_JEQ
, dst_reg
, 0, 1);
2138 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, dst_reg
,
2139 offsetof(struct net_device
, ifindex
));
2142 case offsetof(struct __sk_buff
, hash
):
2143 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, hash
) != 4);
2145 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2146 offsetof(struct sk_buff
, hash
));
2149 case offsetof(struct __sk_buff
, mark
):
2150 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, mark
) != 4);
2152 if (type
== BPF_WRITE
)
2153 *insn
++ = BPF_STX_MEM(BPF_W
, dst_reg
, src_reg
,
2154 offsetof(struct sk_buff
, mark
));
2156 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2157 offsetof(struct sk_buff
, mark
));
2160 case offsetof(struct __sk_buff
, pkt_type
):
2161 return convert_skb_access(SKF_AD_PKTTYPE
, dst_reg
, src_reg
, insn
);
2163 case offsetof(struct __sk_buff
, queue_mapping
):
2164 return convert_skb_access(SKF_AD_QUEUE
, dst_reg
, src_reg
, insn
);
2166 case offsetof(struct __sk_buff
, vlan_present
):
2167 return convert_skb_access(SKF_AD_VLAN_TAG_PRESENT
,
2168 dst_reg
, src_reg
, insn
);
2170 case offsetof(struct __sk_buff
, vlan_tci
):
2171 return convert_skb_access(SKF_AD_VLAN_TAG
,
2172 dst_reg
, src_reg
, insn
);
2174 case offsetof(struct __sk_buff
, cb
[0]) ...
2175 offsetof(struct __sk_buff
, cb
[4]):
2176 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb
, data
) < 20);
2178 prog
->cb_access
= 1;
2179 ctx_off
-= offsetof(struct __sk_buff
, cb
[0]);
2180 ctx_off
+= offsetof(struct sk_buff
, cb
);
2181 ctx_off
+= offsetof(struct qdisc_skb_cb
, data
);
2182 if (type
== BPF_WRITE
)
2183 *insn
++ = BPF_STX_MEM(BPF_W
, dst_reg
, src_reg
, ctx_off
);
2185 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
, ctx_off
);
2188 case offsetof(struct __sk_buff
, tc_classid
):
2189 ctx_off
-= offsetof(struct __sk_buff
, tc_classid
);
2190 ctx_off
+= offsetof(struct sk_buff
, cb
);
2191 ctx_off
+= offsetof(struct qdisc_skb_cb
, tc_classid
);
2192 if (type
== BPF_WRITE
)
2193 *insn
++ = BPF_STX_MEM(BPF_H
, dst_reg
, src_reg
, ctx_off
);
2195 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
, ctx_off
);
2198 case offsetof(struct __sk_buff
, tc_index
):
2199 #ifdef CONFIG_NET_SCHED
2200 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, tc_index
) != 2);
2202 if (type
== BPF_WRITE
)
2203 *insn
++ = BPF_STX_MEM(BPF_H
, dst_reg
, src_reg
,
2204 offsetof(struct sk_buff
, tc_index
));
2206 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
2207 offsetof(struct sk_buff
, tc_index
));
2210 if (type
== BPF_WRITE
)
2211 *insn
++ = BPF_MOV64_REG(dst_reg
, dst_reg
);
2213 *insn
++ = BPF_MOV64_IMM(dst_reg
, 0);
2218 return insn
- insn_buf
;
2221 static const struct bpf_verifier_ops sk_filter_ops
= {
2222 .get_func_proto
= sk_filter_func_proto
,
2223 .is_valid_access
= sk_filter_is_valid_access
,
2224 .convert_ctx_access
= bpf_net_convert_ctx_access
,
2227 static const struct bpf_verifier_ops tc_cls_act_ops
= {
2228 .get_func_proto
= tc_cls_act_func_proto
,
2229 .is_valid_access
= tc_cls_act_is_valid_access
,
2230 .convert_ctx_access
= bpf_net_convert_ctx_access
,
2233 static struct bpf_prog_type_list sk_filter_type __read_mostly
= {
2234 .ops
= &sk_filter_ops
,
2235 .type
= BPF_PROG_TYPE_SOCKET_FILTER
,
2238 static struct bpf_prog_type_list sched_cls_type __read_mostly
= {
2239 .ops
= &tc_cls_act_ops
,
2240 .type
= BPF_PROG_TYPE_SCHED_CLS
,
2243 static struct bpf_prog_type_list sched_act_type __read_mostly
= {
2244 .ops
= &tc_cls_act_ops
,
2245 .type
= BPF_PROG_TYPE_SCHED_ACT
,
2248 static int __init
register_sk_filter_ops(void)
2250 bpf_register_prog_type(&sk_filter_type
);
2251 bpf_register_prog_type(&sched_cls_type
);
2252 bpf_register_prog_type(&sched_act_type
);
2256 late_initcall(register_sk_filter_ops
);
2258 int __sk_detach_filter(struct sock
*sk
, bool locked
)
2261 struct sk_filter
*filter
;
2263 if (sock_flag(sk
, SOCK_FILTER_LOCKED
))
2266 filter
= rcu_dereference_protected(sk
->sk_filter
, locked
);
2268 RCU_INIT_POINTER(sk
->sk_filter
, NULL
);
2269 sk_filter_uncharge(sk
, filter
);
2275 EXPORT_SYMBOL_GPL(__sk_detach_filter
);
2277 int sk_detach_filter(struct sock
*sk
)
2279 return __sk_detach_filter(sk
, sock_owned_by_user(sk
));
2282 int sk_get_filter(struct sock
*sk
, struct sock_filter __user
*ubuf
,
2285 struct sock_fprog_kern
*fprog
;
2286 struct sk_filter
*filter
;
2290 filter
= rcu_dereference_protected(sk
->sk_filter
,
2291 sock_owned_by_user(sk
));
2295 /* We're copying the filter that has been originally attached,
2296 * so no conversion/decode needed anymore. eBPF programs that
2297 * have no original program cannot be dumped through this.
2300 fprog
= filter
->prog
->orig_prog
;
2306 /* User space only enquires number of filter blocks. */
2310 if (len
< fprog
->len
)
2314 if (copy_to_user(ubuf
, fprog
->filter
, bpf_classic_proglen(fprog
)))
2317 /* Instead of bytes, the API requests to return the number