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
)
1154 struct sk_filter
*fp
, *old_fp
;
1156 fp
= kmalloc(sizeof(*fp
), GFP_KERNEL
);
1161 atomic_set(&fp
->refcnt
, 0);
1163 if (!sk_filter_charge(sk
, fp
)) {
1168 old_fp
= rcu_dereference_protected(sk
->sk_filter
,
1169 sock_owned_by_user(sk
));
1170 rcu_assign_pointer(sk
->sk_filter
, fp
);
1173 sk_filter_uncharge(sk
, old_fp
);
1178 static int __reuseport_attach_prog(struct bpf_prog
*prog
, struct sock
*sk
)
1180 struct bpf_prog
*old_prog
;
1183 if (bpf_prog_size(prog
->len
) > sysctl_optmem_max
)
1186 if (sk_unhashed(sk
) && sk
->sk_reuseport
) {
1187 err
= reuseport_alloc(sk
);
1190 } else if (!rcu_access_pointer(sk
->sk_reuseport_cb
)) {
1191 /* The socket wasn't bound with SO_REUSEPORT */
1195 old_prog
= reuseport_attach_prog(sk
, prog
);
1197 bpf_prog_destroy(old_prog
);
1203 struct bpf_prog
*__get_filter(struct sock_fprog
*fprog
, struct sock
*sk
)
1205 unsigned int fsize
= bpf_classic_proglen(fprog
);
1206 unsigned int bpf_fsize
= bpf_prog_size(fprog
->len
);
1207 struct bpf_prog
*prog
;
1210 if (sock_flag(sk
, SOCK_FILTER_LOCKED
))
1211 return ERR_PTR(-EPERM
);
1213 /* Make sure new filter is there and in the right amounts. */
1214 if (fprog
->filter
== NULL
)
1215 return ERR_PTR(-EINVAL
);
1217 prog
= bpf_prog_alloc(bpf_fsize
, 0);
1219 return ERR_PTR(-ENOMEM
);
1221 if (copy_from_user(prog
->insns
, fprog
->filter
, fsize
)) {
1222 __bpf_prog_free(prog
);
1223 return ERR_PTR(-EFAULT
);
1226 prog
->len
= fprog
->len
;
1228 err
= bpf_prog_store_orig_filter(prog
, fprog
);
1230 __bpf_prog_free(prog
);
1231 return ERR_PTR(-ENOMEM
);
1234 /* bpf_prepare_filter() already takes care of freeing
1235 * memory in case something goes wrong.
1237 return bpf_prepare_filter(prog
, NULL
);
1241 * sk_attach_filter - attach a socket filter
1242 * @fprog: the filter program
1243 * @sk: the socket to use
1245 * Attach the user's filter code. We first run some sanity checks on
1246 * it to make sure it does not explode on us later. If an error
1247 * occurs or there is insufficient memory for the filter a negative
1248 * errno code is returned. On success the return is zero.
1250 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
);
1260 __bpf_prog_release(prog
);
1266 EXPORT_SYMBOL_GPL(sk_attach_filter
);
1268 int sk_reuseport_attach_filter(struct sock_fprog
*fprog
, struct sock
*sk
)
1270 struct bpf_prog
*prog
= __get_filter(fprog
, sk
);
1274 return PTR_ERR(prog
);
1276 err
= __reuseport_attach_prog(prog
, sk
);
1278 __bpf_prog_release(prog
);
1285 static struct bpf_prog
*__get_bpf(u32 ufd
, struct sock
*sk
)
1287 struct bpf_prog
*prog
;
1289 if (sock_flag(sk
, SOCK_FILTER_LOCKED
))
1290 return ERR_PTR(-EPERM
);
1292 prog
= bpf_prog_get(ufd
);
1296 if (prog
->type
!= BPF_PROG_TYPE_SOCKET_FILTER
) {
1298 return ERR_PTR(-EINVAL
);
1304 int sk_attach_bpf(u32 ufd
, struct sock
*sk
)
1306 struct bpf_prog
*prog
= __get_bpf(ufd
, sk
);
1310 return PTR_ERR(prog
);
1312 err
= __sk_attach_prog(prog
, sk
);
1321 int sk_reuseport_attach_bpf(u32 ufd
, struct sock
*sk
)
1323 struct bpf_prog
*prog
= __get_bpf(ufd
, sk
);
1327 return PTR_ERR(prog
);
1329 err
= __reuseport_attach_prog(prog
, sk
);
1338 struct bpf_scratchpad
{
1340 __be32 diff
[MAX_BPF_STACK
/ sizeof(__be32
)];
1341 u8 buff
[MAX_BPF_STACK
];
1345 static DEFINE_PER_CPU(struct bpf_scratchpad
, bpf_sp
);
1347 static u64
bpf_skb_store_bytes(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 flags
)
1349 struct bpf_scratchpad
*sp
= this_cpu_ptr(&bpf_sp
);
1350 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1351 int offset
= (int) r2
;
1352 void *from
= (void *) (long) r3
;
1353 unsigned int len
= (unsigned int) r4
;
1356 if (unlikely(flags
& ~(BPF_F_RECOMPUTE_CSUM
| BPF_F_INVALIDATE_HASH
)))
1359 /* bpf verifier guarantees that:
1360 * 'from' pointer points to bpf program stack
1361 * 'len' bytes of it were initialized
1363 * 'skb' is a valid pointer to 'struct sk_buff'
1365 * so check for invalid 'offset' and too large 'len'
1367 if (unlikely((u32
) offset
> 0xffff || len
> sizeof(sp
->buff
)))
1369 if (unlikely(skb_try_make_writable(skb
, offset
+ len
)))
1372 ptr
= skb_header_pointer(skb
, offset
, len
, sp
->buff
);
1376 if (flags
& BPF_F_RECOMPUTE_CSUM
)
1377 skb_postpull_rcsum(skb
, ptr
, len
);
1379 memcpy(ptr
, from
, len
);
1381 if (ptr
== sp
->buff
)
1382 /* skb_store_bits cannot return -EFAULT here */
1383 skb_store_bits(skb
, offset
, ptr
, len
);
1385 if (flags
& BPF_F_RECOMPUTE_CSUM
)
1386 skb_postpush_rcsum(skb
, ptr
, len
);
1387 if (flags
& BPF_F_INVALIDATE_HASH
)
1388 skb_clear_hash(skb
);
1393 static const struct bpf_func_proto bpf_skb_store_bytes_proto
= {
1394 .func
= bpf_skb_store_bytes
,
1396 .ret_type
= RET_INTEGER
,
1397 .arg1_type
= ARG_PTR_TO_CTX
,
1398 .arg2_type
= ARG_ANYTHING
,
1399 .arg3_type
= ARG_PTR_TO_STACK
,
1400 .arg4_type
= ARG_CONST_STACK_SIZE
,
1401 .arg5_type
= ARG_ANYTHING
,
1404 static u64
bpf_skb_load_bytes(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
1406 const struct sk_buff
*skb
= (const struct sk_buff
*)(unsigned long) r1
;
1407 int offset
= (int) r2
;
1408 void *to
= (void *)(unsigned long) r3
;
1409 unsigned int len
= (unsigned int) r4
;
1412 if (unlikely((u32
) offset
> 0xffff || len
> MAX_BPF_STACK
))
1415 ptr
= skb_header_pointer(skb
, offset
, len
, to
);
1419 memcpy(to
, ptr
, len
);
1424 static const struct bpf_func_proto bpf_skb_load_bytes_proto
= {
1425 .func
= bpf_skb_load_bytes
,
1427 .ret_type
= RET_INTEGER
,
1428 .arg1_type
= ARG_PTR_TO_CTX
,
1429 .arg2_type
= ARG_ANYTHING
,
1430 .arg3_type
= ARG_PTR_TO_STACK
,
1431 .arg4_type
= ARG_CONST_STACK_SIZE
,
1434 static u64
bpf_l3_csum_replace(u64 r1
, u64 r2
, u64 from
, u64 to
, u64 flags
)
1436 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1437 int offset
= (int) r2
;
1440 if (unlikely(flags
& ~(BPF_F_HDR_FIELD_MASK
)))
1442 if (unlikely((u32
) offset
> 0xffff))
1444 if (unlikely(skb_try_make_writable(skb
, offset
+ sizeof(sum
))))
1447 ptr
= skb_header_pointer(skb
, offset
, sizeof(sum
), &sum
);
1451 switch (flags
& BPF_F_HDR_FIELD_MASK
) {
1453 if (unlikely(from
!= 0))
1456 csum_replace_by_diff(ptr
, to
);
1459 csum_replace2(ptr
, from
, to
);
1462 csum_replace4(ptr
, from
, to
);
1469 /* skb_store_bits guaranteed to not return -EFAULT here */
1470 skb_store_bits(skb
, offset
, ptr
, sizeof(sum
));
1475 static const struct bpf_func_proto bpf_l3_csum_replace_proto
= {
1476 .func
= bpf_l3_csum_replace
,
1478 .ret_type
= RET_INTEGER
,
1479 .arg1_type
= ARG_PTR_TO_CTX
,
1480 .arg2_type
= ARG_ANYTHING
,
1481 .arg3_type
= ARG_ANYTHING
,
1482 .arg4_type
= ARG_ANYTHING
,
1483 .arg5_type
= ARG_ANYTHING
,
1486 static u64
bpf_l4_csum_replace(u64 r1
, u64 r2
, u64 from
, u64 to
, u64 flags
)
1488 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1489 bool is_pseudo
= flags
& BPF_F_PSEUDO_HDR
;
1490 bool is_mmzero
= flags
& BPF_F_MARK_MANGLED_0
;
1491 int offset
= (int) r2
;
1494 if (unlikely(flags
& ~(BPF_F_MARK_MANGLED_0
| BPF_F_PSEUDO_HDR
|
1495 BPF_F_HDR_FIELD_MASK
)))
1497 if (unlikely((u32
) offset
> 0xffff))
1499 if (unlikely(skb_try_make_writable(skb
, offset
+ sizeof(sum
))))
1502 ptr
= skb_header_pointer(skb
, offset
, sizeof(sum
), &sum
);
1505 if (is_mmzero
&& !*ptr
)
1508 switch (flags
& BPF_F_HDR_FIELD_MASK
) {
1510 if (unlikely(from
!= 0))
1513 inet_proto_csum_replace_by_diff(ptr
, skb
, to
, is_pseudo
);
1516 inet_proto_csum_replace2(ptr
, skb
, from
, to
, is_pseudo
);
1519 inet_proto_csum_replace4(ptr
, skb
, from
, to
, is_pseudo
);
1525 if (is_mmzero
&& !*ptr
)
1526 *ptr
= CSUM_MANGLED_0
;
1528 /* skb_store_bits guaranteed to not return -EFAULT here */
1529 skb_store_bits(skb
, offset
, ptr
, sizeof(sum
));
1534 static const struct bpf_func_proto bpf_l4_csum_replace_proto
= {
1535 .func
= bpf_l4_csum_replace
,
1537 .ret_type
= RET_INTEGER
,
1538 .arg1_type
= ARG_PTR_TO_CTX
,
1539 .arg2_type
= ARG_ANYTHING
,
1540 .arg3_type
= ARG_ANYTHING
,
1541 .arg4_type
= ARG_ANYTHING
,
1542 .arg5_type
= ARG_ANYTHING
,
1545 static u64
bpf_csum_diff(u64 r1
, u64 from_size
, u64 r3
, u64 to_size
, u64 seed
)
1547 struct bpf_scratchpad
*sp
= this_cpu_ptr(&bpf_sp
);
1548 u64 diff_size
= from_size
+ to_size
;
1549 __be32
*from
= (__be32
*) (long) r1
;
1550 __be32
*to
= (__be32
*) (long) r3
;
1553 /* This is quite flexible, some examples:
1555 * from_size == 0, to_size > 0, seed := csum --> pushing data
1556 * from_size > 0, to_size == 0, seed := csum --> pulling data
1557 * from_size > 0, to_size > 0, seed := 0 --> diffing data
1559 * Even for diffing, from_size and to_size don't need to be equal.
1561 if (unlikely(((from_size
| to_size
) & (sizeof(__be32
) - 1)) ||
1562 diff_size
> sizeof(sp
->diff
)))
1565 for (i
= 0; i
< from_size
/ sizeof(__be32
); i
++, j
++)
1566 sp
->diff
[j
] = ~from
[i
];
1567 for (i
= 0; i
< to_size
/ sizeof(__be32
); i
++, j
++)
1568 sp
->diff
[j
] = to
[i
];
1570 return csum_partial(sp
->diff
, diff_size
, seed
);
1573 static const struct bpf_func_proto bpf_csum_diff_proto
= {
1574 .func
= bpf_csum_diff
,
1576 .ret_type
= RET_INTEGER
,
1577 .arg1_type
= ARG_PTR_TO_STACK
,
1578 .arg2_type
= ARG_CONST_STACK_SIZE_OR_ZERO
,
1579 .arg3_type
= ARG_PTR_TO_STACK
,
1580 .arg4_type
= ARG_CONST_STACK_SIZE_OR_ZERO
,
1581 .arg5_type
= ARG_ANYTHING
,
1584 static u64
bpf_clone_redirect(u64 r1
, u64 ifindex
, u64 flags
, u64 r4
, u64 r5
)
1586 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
, *skb2
;
1587 struct net_device
*dev
;
1589 if (unlikely(flags
& ~(BPF_F_INGRESS
)))
1592 dev
= dev_get_by_index_rcu(dev_net(skb
->dev
), ifindex
);
1596 skb2
= skb_clone(skb
, GFP_ATOMIC
);
1597 if (unlikely(!skb2
))
1600 if (flags
& BPF_F_INGRESS
) {
1601 if (skb_at_tc_ingress(skb2
))
1602 skb_postpush_rcsum(skb2
, skb_mac_header(skb2
),
1604 return dev_forward_skb(dev
, skb2
);
1608 return dev_queue_xmit(skb2
);
1611 static const struct bpf_func_proto bpf_clone_redirect_proto
= {
1612 .func
= bpf_clone_redirect
,
1614 .ret_type
= RET_INTEGER
,
1615 .arg1_type
= ARG_PTR_TO_CTX
,
1616 .arg2_type
= ARG_ANYTHING
,
1617 .arg3_type
= ARG_ANYTHING
,
1620 struct redirect_info
{
1625 static DEFINE_PER_CPU(struct redirect_info
, redirect_info
);
1627 static u64
bpf_redirect(u64 ifindex
, u64 flags
, u64 r3
, u64 r4
, u64 r5
)
1629 struct redirect_info
*ri
= this_cpu_ptr(&redirect_info
);
1631 if (unlikely(flags
& ~(BPF_F_INGRESS
)))
1634 ri
->ifindex
= ifindex
;
1637 return TC_ACT_REDIRECT
;
1640 int skb_do_redirect(struct sk_buff
*skb
)
1642 struct redirect_info
*ri
= this_cpu_ptr(&redirect_info
);
1643 struct net_device
*dev
;
1645 dev
= dev_get_by_index_rcu(dev_net(skb
->dev
), ri
->ifindex
);
1647 if (unlikely(!dev
)) {
1652 if (ri
->flags
& BPF_F_INGRESS
) {
1653 if (skb_at_tc_ingress(skb
))
1654 skb_postpush_rcsum(skb
, skb_mac_header(skb
),
1656 return dev_forward_skb(dev
, skb
);
1660 return dev_queue_xmit(skb
);
1663 static const struct bpf_func_proto bpf_redirect_proto
= {
1664 .func
= bpf_redirect
,
1666 .ret_type
= RET_INTEGER
,
1667 .arg1_type
= ARG_ANYTHING
,
1668 .arg2_type
= ARG_ANYTHING
,
1671 static u64
bpf_get_cgroup_classid(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
1673 return task_get_classid((struct sk_buff
*) (unsigned long) r1
);
1676 static const struct bpf_func_proto bpf_get_cgroup_classid_proto
= {
1677 .func
= bpf_get_cgroup_classid
,
1679 .ret_type
= RET_INTEGER
,
1680 .arg1_type
= ARG_PTR_TO_CTX
,
1683 static u64
bpf_get_route_realm(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
1685 return dst_tclassid((struct sk_buff
*) (unsigned long) r1
);
1688 static const struct bpf_func_proto bpf_get_route_realm_proto
= {
1689 .func
= bpf_get_route_realm
,
1691 .ret_type
= RET_INTEGER
,
1692 .arg1_type
= ARG_PTR_TO_CTX
,
1695 static u64
bpf_skb_vlan_push(u64 r1
, u64 r2
, u64 vlan_tci
, u64 r4
, u64 r5
)
1697 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1698 __be16 vlan_proto
= (__force __be16
) r2
;
1700 if (unlikely(vlan_proto
!= htons(ETH_P_8021Q
) &&
1701 vlan_proto
!= htons(ETH_P_8021AD
)))
1702 vlan_proto
= htons(ETH_P_8021Q
);
1704 return skb_vlan_push(skb
, vlan_proto
, vlan_tci
);
1707 const struct bpf_func_proto bpf_skb_vlan_push_proto
= {
1708 .func
= bpf_skb_vlan_push
,
1710 .ret_type
= RET_INTEGER
,
1711 .arg1_type
= ARG_PTR_TO_CTX
,
1712 .arg2_type
= ARG_ANYTHING
,
1713 .arg3_type
= ARG_ANYTHING
,
1715 EXPORT_SYMBOL_GPL(bpf_skb_vlan_push_proto
);
1717 static u64
bpf_skb_vlan_pop(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
)
1719 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1721 return skb_vlan_pop(skb
);
1724 const struct bpf_func_proto bpf_skb_vlan_pop_proto
= {
1725 .func
= bpf_skb_vlan_pop
,
1727 .ret_type
= RET_INTEGER
,
1728 .arg1_type
= ARG_PTR_TO_CTX
,
1730 EXPORT_SYMBOL_GPL(bpf_skb_vlan_pop_proto
);
1732 bool bpf_helper_changes_skb_data(void *func
)
1734 if (func
== bpf_skb_vlan_push
)
1736 if (func
== bpf_skb_vlan_pop
)
1738 if (func
== bpf_skb_store_bytes
)
1740 if (func
== bpf_l3_csum_replace
)
1742 if (func
== bpf_l4_csum_replace
)
1748 static unsigned short bpf_tunnel_key_af(u64 flags
)
1750 return flags
& BPF_F_TUNINFO_IPV6
? AF_INET6
: AF_INET
;
1753 static u64
bpf_skb_get_tunnel_key(u64 r1
, u64 r2
, u64 size
, u64 flags
, u64 r5
)
1755 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1756 struct bpf_tunnel_key
*to
= (struct bpf_tunnel_key
*) (long) r2
;
1757 const struct ip_tunnel_info
*info
= skb_tunnel_info(skb
);
1758 u8 compat
[sizeof(struct bpf_tunnel_key
)];
1760 if (unlikely(!info
|| (flags
& ~(BPF_F_TUNINFO_IPV6
))))
1762 if (ip_tunnel_info_af(info
) != bpf_tunnel_key_af(flags
))
1764 if (unlikely(size
!= sizeof(struct bpf_tunnel_key
))) {
1766 case offsetof(struct bpf_tunnel_key
, tunnel_label
):
1768 case offsetof(struct bpf_tunnel_key
, remote_ipv6
[1]):
1769 /* Fixup deprecated structure layouts here, so we have
1770 * a common path later on.
1772 if (ip_tunnel_info_af(info
) != AF_INET
)
1775 to
= (struct bpf_tunnel_key
*)compat
;
1782 to
->tunnel_id
= be64_to_cpu(info
->key
.tun_id
);
1783 to
->tunnel_tos
= info
->key
.tos
;
1784 to
->tunnel_ttl
= info
->key
.ttl
;
1786 if (flags
& BPF_F_TUNINFO_IPV6
) {
1787 memcpy(to
->remote_ipv6
, &info
->key
.u
.ipv6
.src
,
1788 sizeof(to
->remote_ipv6
));
1789 to
->tunnel_label
= be32_to_cpu(info
->key
.label
);
1791 to
->remote_ipv4
= be32_to_cpu(info
->key
.u
.ipv4
.src
);
1794 if (unlikely(size
!= sizeof(struct bpf_tunnel_key
)))
1795 memcpy((void *)(long) r2
, to
, size
);
1800 static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto
= {
1801 .func
= bpf_skb_get_tunnel_key
,
1803 .ret_type
= RET_INTEGER
,
1804 .arg1_type
= ARG_PTR_TO_CTX
,
1805 .arg2_type
= ARG_PTR_TO_STACK
,
1806 .arg3_type
= ARG_CONST_STACK_SIZE
,
1807 .arg4_type
= ARG_ANYTHING
,
1810 static u64
bpf_skb_get_tunnel_opt(u64 r1
, u64 r2
, u64 size
, u64 r4
, u64 r5
)
1812 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1813 u8
*to
= (u8
*) (long) r2
;
1814 const struct ip_tunnel_info
*info
= skb_tunnel_info(skb
);
1816 if (unlikely(!info
||
1817 !(info
->key
.tun_flags
& TUNNEL_OPTIONS_PRESENT
)))
1819 if (unlikely(size
< info
->options_len
))
1822 ip_tunnel_info_opts_get(to
, info
);
1824 return info
->options_len
;
1827 static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto
= {
1828 .func
= bpf_skb_get_tunnel_opt
,
1830 .ret_type
= RET_INTEGER
,
1831 .arg1_type
= ARG_PTR_TO_CTX
,
1832 .arg2_type
= ARG_PTR_TO_STACK
,
1833 .arg3_type
= ARG_CONST_STACK_SIZE
,
1836 static struct metadata_dst __percpu
*md_dst
;
1838 static u64
bpf_skb_set_tunnel_key(u64 r1
, u64 r2
, u64 size
, u64 flags
, u64 r5
)
1840 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1841 struct bpf_tunnel_key
*from
= (struct bpf_tunnel_key
*) (long) r2
;
1842 struct metadata_dst
*md
= this_cpu_ptr(md_dst
);
1843 u8 compat
[sizeof(struct bpf_tunnel_key
)];
1844 struct ip_tunnel_info
*info
;
1846 if (unlikely(flags
& ~(BPF_F_TUNINFO_IPV6
| BPF_F_ZERO_CSUM_TX
|
1847 BPF_F_DONT_FRAGMENT
)))
1849 if (unlikely(size
!= sizeof(struct bpf_tunnel_key
))) {
1851 case offsetof(struct bpf_tunnel_key
, tunnel_label
):
1852 case offsetof(struct bpf_tunnel_key
, remote_ipv6
[1]):
1853 /* Fixup deprecated structure layouts here, so we have
1854 * a common path later on.
1856 memcpy(compat
, from
, size
);
1857 memset(compat
+ size
, 0, sizeof(compat
) - size
);
1858 from
= (struct bpf_tunnel_key
*)compat
;
1864 if (unlikely(!(flags
& BPF_F_TUNINFO_IPV6
) && from
->tunnel_label
))
1868 dst_hold((struct dst_entry
*) md
);
1869 skb_dst_set(skb
, (struct dst_entry
*) md
);
1871 info
= &md
->u
.tun_info
;
1872 info
->mode
= IP_TUNNEL_INFO_TX
;
1874 info
->key
.tun_flags
= TUNNEL_KEY
| TUNNEL_CSUM
| TUNNEL_NOCACHE
;
1875 if (flags
& BPF_F_DONT_FRAGMENT
)
1876 info
->key
.tun_flags
|= TUNNEL_DONT_FRAGMENT
;
1878 info
->key
.tun_id
= cpu_to_be64(from
->tunnel_id
);
1879 info
->key
.tos
= from
->tunnel_tos
;
1880 info
->key
.ttl
= from
->tunnel_ttl
;
1882 if (flags
& BPF_F_TUNINFO_IPV6
) {
1883 info
->mode
|= IP_TUNNEL_INFO_IPV6
;
1884 memcpy(&info
->key
.u
.ipv6
.dst
, from
->remote_ipv6
,
1885 sizeof(from
->remote_ipv6
));
1886 info
->key
.label
= cpu_to_be32(from
->tunnel_label
) &
1887 IPV6_FLOWLABEL_MASK
;
1889 info
->key
.u
.ipv4
.dst
= cpu_to_be32(from
->remote_ipv4
);
1890 if (flags
& BPF_F_ZERO_CSUM_TX
)
1891 info
->key
.tun_flags
&= ~TUNNEL_CSUM
;
1897 static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto
= {
1898 .func
= bpf_skb_set_tunnel_key
,
1900 .ret_type
= RET_INTEGER
,
1901 .arg1_type
= ARG_PTR_TO_CTX
,
1902 .arg2_type
= ARG_PTR_TO_STACK
,
1903 .arg3_type
= ARG_CONST_STACK_SIZE
,
1904 .arg4_type
= ARG_ANYTHING
,
1907 static u64
bpf_skb_set_tunnel_opt(u64 r1
, u64 r2
, u64 size
, u64 r4
, u64 r5
)
1909 struct sk_buff
*skb
= (struct sk_buff
*) (long) r1
;
1910 u8
*from
= (u8
*) (long) r2
;
1911 struct ip_tunnel_info
*info
= skb_tunnel_info(skb
);
1912 const struct metadata_dst
*md
= this_cpu_ptr(md_dst
);
1914 if (unlikely(info
!= &md
->u
.tun_info
|| (size
& (sizeof(u32
) - 1))))
1916 if (unlikely(size
> IP_TUNNEL_OPTS_MAX
))
1919 ip_tunnel_info_opts_set(info
, from
, size
);
1924 static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto
= {
1925 .func
= bpf_skb_set_tunnel_opt
,
1927 .ret_type
= RET_INTEGER
,
1928 .arg1_type
= ARG_PTR_TO_CTX
,
1929 .arg2_type
= ARG_PTR_TO_STACK
,
1930 .arg3_type
= ARG_CONST_STACK_SIZE
,
1933 static const struct bpf_func_proto
*
1934 bpf_get_skb_set_tunnel_proto(enum bpf_func_id which
)
1937 /* Race is not possible, since it's called from verifier
1938 * that is holding verifier mutex.
1940 md_dst
= metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX
,
1947 case BPF_FUNC_skb_set_tunnel_key
:
1948 return &bpf_skb_set_tunnel_key_proto
;
1949 case BPF_FUNC_skb_set_tunnel_opt
:
1950 return &bpf_skb_set_tunnel_opt_proto
;
1956 static const struct bpf_func_proto
*
1957 sk_filter_func_proto(enum bpf_func_id func_id
)
1960 case BPF_FUNC_map_lookup_elem
:
1961 return &bpf_map_lookup_elem_proto
;
1962 case BPF_FUNC_map_update_elem
:
1963 return &bpf_map_update_elem_proto
;
1964 case BPF_FUNC_map_delete_elem
:
1965 return &bpf_map_delete_elem_proto
;
1966 case BPF_FUNC_get_prandom_u32
:
1967 return &bpf_get_prandom_u32_proto
;
1968 case BPF_FUNC_get_smp_processor_id
:
1969 return &bpf_get_smp_processor_id_proto
;
1970 case BPF_FUNC_tail_call
:
1971 return &bpf_tail_call_proto
;
1972 case BPF_FUNC_ktime_get_ns
:
1973 return &bpf_ktime_get_ns_proto
;
1974 case BPF_FUNC_trace_printk
:
1975 if (capable(CAP_SYS_ADMIN
))
1976 return bpf_get_trace_printk_proto();
1982 static const struct bpf_func_proto
*
1983 tc_cls_act_func_proto(enum bpf_func_id func_id
)
1986 case BPF_FUNC_skb_store_bytes
:
1987 return &bpf_skb_store_bytes_proto
;
1988 case BPF_FUNC_skb_load_bytes
:
1989 return &bpf_skb_load_bytes_proto
;
1990 case BPF_FUNC_csum_diff
:
1991 return &bpf_csum_diff_proto
;
1992 case BPF_FUNC_l3_csum_replace
:
1993 return &bpf_l3_csum_replace_proto
;
1994 case BPF_FUNC_l4_csum_replace
:
1995 return &bpf_l4_csum_replace_proto
;
1996 case BPF_FUNC_clone_redirect
:
1997 return &bpf_clone_redirect_proto
;
1998 case BPF_FUNC_get_cgroup_classid
:
1999 return &bpf_get_cgroup_classid_proto
;
2000 case BPF_FUNC_skb_vlan_push
:
2001 return &bpf_skb_vlan_push_proto
;
2002 case BPF_FUNC_skb_vlan_pop
:
2003 return &bpf_skb_vlan_pop_proto
;
2004 case BPF_FUNC_skb_get_tunnel_key
:
2005 return &bpf_skb_get_tunnel_key_proto
;
2006 case BPF_FUNC_skb_set_tunnel_key
:
2007 return bpf_get_skb_set_tunnel_proto(func_id
);
2008 case BPF_FUNC_skb_get_tunnel_opt
:
2009 return &bpf_skb_get_tunnel_opt_proto
;
2010 case BPF_FUNC_skb_set_tunnel_opt
:
2011 return bpf_get_skb_set_tunnel_proto(func_id
);
2012 case BPF_FUNC_redirect
:
2013 return &bpf_redirect_proto
;
2014 case BPF_FUNC_get_route_realm
:
2015 return &bpf_get_route_realm_proto
;
2017 return sk_filter_func_proto(func_id
);
2021 static bool __is_valid_access(int off
, int size
, enum bpf_access_type type
)
2024 if (off
< 0 || off
>= sizeof(struct __sk_buff
))
2027 /* disallow misaligned access */
2028 if (off
% size
!= 0)
2031 /* all __sk_buff fields are __u32 */
2038 static bool sk_filter_is_valid_access(int off
, int size
,
2039 enum bpf_access_type type
)
2041 if (off
== offsetof(struct __sk_buff
, tc_classid
))
2044 if (type
== BPF_WRITE
) {
2046 case offsetof(struct __sk_buff
, cb
[0]) ...
2047 offsetof(struct __sk_buff
, cb
[4]):
2054 return __is_valid_access(off
, size
, type
);
2057 static bool tc_cls_act_is_valid_access(int off
, int size
,
2058 enum bpf_access_type type
)
2060 if (type
== BPF_WRITE
) {
2062 case offsetof(struct __sk_buff
, mark
):
2063 case offsetof(struct __sk_buff
, tc_index
):
2064 case offsetof(struct __sk_buff
, priority
):
2065 case offsetof(struct __sk_buff
, cb
[0]) ...
2066 offsetof(struct __sk_buff
, cb
[4]):
2067 case offsetof(struct __sk_buff
, tc_classid
):
2073 return __is_valid_access(off
, size
, type
);
2076 static u32
bpf_net_convert_ctx_access(enum bpf_access_type type
, int dst_reg
,
2077 int src_reg
, int ctx_off
,
2078 struct bpf_insn
*insn_buf
,
2079 struct bpf_prog
*prog
)
2081 struct bpf_insn
*insn
= insn_buf
;
2084 case offsetof(struct __sk_buff
, len
):
2085 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, len
) != 4);
2087 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2088 offsetof(struct sk_buff
, len
));
2091 case offsetof(struct __sk_buff
, protocol
):
2092 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, protocol
) != 2);
2094 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
2095 offsetof(struct sk_buff
, protocol
));
2098 case offsetof(struct __sk_buff
, vlan_proto
):
2099 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, vlan_proto
) != 2);
2101 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
2102 offsetof(struct sk_buff
, vlan_proto
));
2105 case offsetof(struct __sk_buff
, priority
):
2106 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, priority
) != 4);
2108 if (type
== BPF_WRITE
)
2109 *insn
++ = BPF_STX_MEM(BPF_W
, dst_reg
, src_reg
,
2110 offsetof(struct sk_buff
, priority
));
2112 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2113 offsetof(struct sk_buff
, priority
));
2116 case offsetof(struct __sk_buff
, ingress_ifindex
):
2117 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, skb_iif
) != 4);
2119 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2120 offsetof(struct sk_buff
, skb_iif
));
2123 case offsetof(struct __sk_buff
, ifindex
):
2124 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device
, ifindex
) != 4);
2126 *insn
++ = BPF_LDX_MEM(bytes_to_bpf_size(FIELD_SIZEOF(struct sk_buff
, dev
)),
2128 offsetof(struct sk_buff
, dev
));
2129 *insn
++ = BPF_JMP_IMM(BPF_JEQ
, dst_reg
, 0, 1);
2130 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, dst_reg
,
2131 offsetof(struct net_device
, ifindex
));
2134 case offsetof(struct __sk_buff
, hash
):
2135 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, hash
) != 4);
2137 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2138 offsetof(struct sk_buff
, hash
));
2141 case offsetof(struct __sk_buff
, mark
):
2142 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, mark
) != 4);
2144 if (type
== BPF_WRITE
)
2145 *insn
++ = BPF_STX_MEM(BPF_W
, dst_reg
, src_reg
,
2146 offsetof(struct sk_buff
, mark
));
2148 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
,
2149 offsetof(struct sk_buff
, mark
));
2152 case offsetof(struct __sk_buff
, pkt_type
):
2153 return convert_skb_access(SKF_AD_PKTTYPE
, dst_reg
, src_reg
, insn
);
2155 case offsetof(struct __sk_buff
, queue_mapping
):
2156 return convert_skb_access(SKF_AD_QUEUE
, dst_reg
, src_reg
, insn
);
2158 case offsetof(struct __sk_buff
, vlan_present
):
2159 return convert_skb_access(SKF_AD_VLAN_TAG_PRESENT
,
2160 dst_reg
, src_reg
, insn
);
2162 case offsetof(struct __sk_buff
, vlan_tci
):
2163 return convert_skb_access(SKF_AD_VLAN_TAG
,
2164 dst_reg
, src_reg
, insn
);
2166 case offsetof(struct __sk_buff
, cb
[0]) ...
2167 offsetof(struct __sk_buff
, cb
[4]):
2168 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb
, data
) < 20);
2170 prog
->cb_access
= 1;
2171 ctx_off
-= offsetof(struct __sk_buff
, cb
[0]);
2172 ctx_off
+= offsetof(struct sk_buff
, cb
);
2173 ctx_off
+= offsetof(struct qdisc_skb_cb
, data
);
2174 if (type
== BPF_WRITE
)
2175 *insn
++ = BPF_STX_MEM(BPF_W
, dst_reg
, src_reg
, ctx_off
);
2177 *insn
++ = BPF_LDX_MEM(BPF_W
, dst_reg
, src_reg
, ctx_off
);
2180 case offsetof(struct __sk_buff
, tc_classid
):
2181 ctx_off
-= offsetof(struct __sk_buff
, tc_classid
);
2182 ctx_off
+= offsetof(struct sk_buff
, cb
);
2183 ctx_off
+= offsetof(struct qdisc_skb_cb
, tc_classid
);
2184 if (type
== BPF_WRITE
)
2185 *insn
++ = BPF_STX_MEM(BPF_H
, dst_reg
, src_reg
, ctx_off
);
2187 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
, ctx_off
);
2190 case offsetof(struct __sk_buff
, tc_index
):
2191 #ifdef CONFIG_NET_SCHED
2192 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff
, tc_index
) != 2);
2194 if (type
== BPF_WRITE
)
2195 *insn
++ = BPF_STX_MEM(BPF_H
, dst_reg
, src_reg
,
2196 offsetof(struct sk_buff
, tc_index
));
2198 *insn
++ = BPF_LDX_MEM(BPF_H
, dst_reg
, src_reg
,
2199 offsetof(struct sk_buff
, tc_index
));
2202 if (type
== BPF_WRITE
)
2203 *insn
++ = BPF_MOV64_REG(dst_reg
, dst_reg
);
2205 *insn
++ = BPF_MOV64_IMM(dst_reg
, 0);
2210 return insn
- insn_buf
;
2213 static const struct bpf_verifier_ops sk_filter_ops
= {
2214 .get_func_proto
= sk_filter_func_proto
,
2215 .is_valid_access
= sk_filter_is_valid_access
,
2216 .convert_ctx_access
= bpf_net_convert_ctx_access
,
2219 static const struct bpf_verifier_ops tc_cls_act_ops
= {
2220 .get_func_proto
= tc_cls_act_func_proto
,
2221 .is_valid_access
= tc_cls_act_is_valid_access
,
2222 .convert_ctx_access
= bpf_net_convert_ctx_access
,
2225 static struct bpf_prog_type_list sk_filter_type __read_mostly
= {
2226 .ops
= &sk_filter_ops
,
2227 .type
= BPF_PROG_TYPE_SOCKET_FILTER
,
2230 static struct bpf_prog_type_list sched_cls_type __read_mostly
= {
2231 .ops
= &tc_cls_act_ops
,
2232 .type
= BPF_PROG_TYPE_SCHED_CLS
,
2235 static struct bpf_prog_type_list sched_act_type __read_mostly
= {
2236 .ops
= &tc_cls_act_ops
,
2237 .type
= BPF_PROG_TYPE_SCHED_ACT
,
2240 static int __init
register_sk_filter_ops(void)
2242 bpf_register_prog_type(&sk_filter_type
);
2243 bpf_register_prog_type(&sched_cls_type
);
2244 bpf_register_prog_type(&sched_act_type
);
2248 late_initcall(register_sk_filter_ops
);
2250 int sk_detach_filter(struct sock
*sk
)
2253 struct sk_filter
*filter
;
2255 if (sock_flag(sk
, SOCK_FILTER_LOCKED
))
2258 filter
= rcu_dereference_protected(sk
->sk_filter
,
2259 sock_owned_by_user(sk
));
2261 RCU_INIT_POINTER(sk
->sk_filter
, NULL
);
2262 sk_filter_uncharge(sk
, filter
);
2268 EXPORT_SYMBOL_GPL(sk_detach_filter
);
2270 int sk_get_filter(struct sock
*sk
, struct sock_filter __user
*ubuf
,
2273 struct sock_fprog_kern
*fprog
;
2274 struct sk_filter
*filter
;
2278 filter
= rcu_dereference_protected(sk
->sk_filter
,
2279 sock_owned_by_user(sk
));
2283 /* We're copying the filter that has been originally attached,
2284 * so no conversion/decode needed anymore. eBPF programs that
2285 * have no original program cannot be dumped through this.
2288 fprog
= filter
->prog
->orig_prog
;
2294 /* User space only enquires number of filter blocks. */
2298 if (len
< fprog
->len
)
2302 if (copy_to_user(ubuf
, fprog
->filter
, bpf_classic_proglen(fprog
)))
2305 /* Instead of bytes, the API requests to return the number