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Merge branch 'akpm' (patches from Andrew)
[mirror_ubuntu-bionic-kernel.git] / net / core / filter.c
1 /*
2 * Linux Socket Filter - Kernel level socket filtering
3 *
4 * Based on the design of the Berkeley Packet Filter. The new
5 * internal format has been designed by PLUMgrid:
6 *
7 * Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com
8 *
9 * Authors:
10 *
11 * Jay Schulist <jschlst@samba.org>
12 * Alexei Starovoitov <ast@plumgrid.com>
13 * Daniel Borkmann <dborkman@redhat.com>
14 *
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.
19 *
20 * Andi Kleen - Fix a few bad bugs and races.
21 * Kris Katterjohn - Added many additional checks in bpf_check_classic()
22 */
23
24 #include <linux/module.h>
25 #include <linux/types.h>
26 #include <linux/mm.h>
27 #include <linux/fcntl.h>
28 #include <linux/socket.h>
29 #include <linux/sock_diag.h>
30 #include <linux/in.h>
31 #include <linux/inet.h>
32 #include <linux/netdevice.h>
33 #include <linux/if_packet.h>
34 #include <linux/if_arp.h>
35 #include <linux/gfp.h>
36 #include <net/ip.h>
37 #include <net/protocol.h>
38 #include <net/netlink.h>
39 #include <linux/skbuff.h>
40 #include <net/sock.h>
41 #include <net/flow_dissector.h>
42 #include <linux/errno.h>
43 #include <linux/timer.h>
44 #include <linux/uaccess.h>
45 #include <asm/unaligned.h>
46 #include <asm/cmpxchg.h>
47 #include <linux/filter.h>
48 #include <linux/ratelimit.h>
49 #include <linux/seccomp.h>
50 #include <linux/if_vlan.h>
51 #include <linux/bpf.h>
52 #include <net/sch_generic.h>
53 #include <net/cls_cgroup.h>
54 #include <net/dst_metadata.h>
55 #include <net/dst.h>
56 #include <net/sock_reuseport.h>
57 #include <net/busy_poll.h>
58 #include <net/tcp.h>
59 #include <linux/bpf_trace.h>
60
61 /**
62 * sk_filter_trim_cap - run a packet through a socket filter
63 * @sk: sock associated with &sk_buff
64 * @skb: buffer to filter
65 * @cap: limit on how short the eBPF program may trim the packet
66 *
67 * Run the eBPF program and then cut skb->data to correct size returned by
68 * the program. If pkt_len is 0 we toss packet. If skb->len is smaller
69 * than pkt_len we keep whole skb->data. This is the socket level
70 * wrapper to BPF_PROG_RUN. It returns 0 if the packet should
71 * be accepted or -EPERM if the packet should be tossed.
72 *
73 */
74 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap)
75 {
76 int err;
77 struct sk_filter *filter;
78
79 /*
80 * If the skb was allocated from pfmemalloc reserves, only
81 * allow SOCK_MEMALLOC sockets to use it as this socket is
82 * helping free memory
83 */
84 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) {
85 NET_INC_STATS(sock_net(sk), LINUX_MIB_PFMEMALLOCDROP);
86 return -ENOMEM;
87 }
88 err = BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb);
89 if (err)
90 return err;
91
92 err = security_sock_rcv_skb(sk, skb);
93 if (err)
94 return err;
95
96 rcu_read_lock();
97 filter = rcu_dereference(sk->sk_filter);
98 if (filter) {
99 struct sock *save_sk = skb->sk;
100 unsigned int pkt_len;
101
102 skb->sk = sk;
103 pkt_len = bpf_prog_run_save_cb(filter->prog, skb);
104 skb->sk = save_sk;
105 err = pkt_len ? pskb_trim(skb, max(cap, pkt_len)) : -EPERM;
106 }
107 rcu_read_unlock();
108
109 return err;
110 }
111 EXPORT_SYMBOL(sk_filter_trim_cap);
112
113 BPF_CALL_1(__skb_get_pay_offset, struct sk_buff *, skb)
114 {
115 return skb_get_poff(skb);
116 }
117
118 BPF_CALL_3(__skb_get_nlattr, struct sk_buff *, skb, u32, a, u32, x)
119 {
120 struct nlattr *nla;
121
122 if (skb_is_nonlinear(skb))
123 return 0;
124
125 if (skb->len < sizeof(struct nlattr))
126 return 0;
127
128 if (a > skb->len - sizeof(struct nlattr))
129 return 0;
130
131 nla = nla_find((struct nlattr *) &skb->data[a], skb->len - a, x);
132 if (nla)
133 return (void *) nla - (void *) skb->data;
134
135 return 0;
136 }
137
138 BPF_CALL_3(__skb_get_nlattr_nest, struct sk_buff *, skb, u32, a, u32, x)
139 {
140 struct nlattr *nla;
141
142 if (skb_is_nonlinear(skb))
143 return 0;
144
145 if (skb->len < sizeof(struct nlattr))
146 return 0;
147
148 if (a > skb->len - sizeof(struct nlattr))
149 return 0;
150
151 nla = (struct nlattr *) &skb->data[a];
152 if (nla->nla_len > skb->len - a)
153 return 0;
154
155 nla = nla_find_nested(nla, x);
156 if (nla)
157 return (void *) nla - (void *) skb->data;
158
159 return 0;
160 }
161
162 BPF_CALL_0(__get_raw_cpu_id)
163 {
164 return raw_smp_processor_id();
165 }
166
167 static const struct bpf_func_proto bpf_get_raw_smp_processor_id_proto = {
168 .func = __get_raw_cpu_id,
169 .gpl_only = false,
170 .ret_type = RET_INTEGER,
171 };
172
173 static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg,
174 struct bpf_insn *insn_buf)
175 {
176 struct bpf_insn *insn = insn_buf;
177
178 switch (skb_field) {
179 case SKF_AD_MARK:
180 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, mark) != 4);
181
182 *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
183 offsetof(struct sk_buff, mark));
184 break;
185
186 case SKF_AD_PKTTYPE:
187 *insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_TYPE_OFFSET());
188 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, PKT_TYPE_MAX);
189 #ifdef __BIG_ENDIAN_BITFIELD
190 *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 5);
191 #endif
192 break;
193
194 case SKF_AD_QUEUE:
195 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, queue_mapping) != 2);
196
197 *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
198 offsetof(struct sk_buff, queue_mapping));
199 break;
200
201 case SKF_AD_VLAN_TAG:
202 case SKF_AD_VLAN_TAG_PRESENT:
203 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2);
204 BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
205
206 /* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
207 *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
208 offsetof(struct sk_buff, vlan_tci));
209 if (skb_field == SKF_AD_VLAN_TAG) {
210 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg,
211 ~VLAN_TAG_PRESENT);
212 } else {
213 /* dst_reg >>= 12 */
214 *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 12);
215 /* dst_reg &= 1 */
216 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 1);
217 }
218 break;
219 }
220
221 return insn - insn_buf;
222 }
223
224 static bool convert_bpf_extensions(struct sock_filter *fp,
225 struct bpf_insn **insnp)
226 {
227 struct bpf_insn *insn = *insnp;
228 u32 cnt;
229
230 switch (fp->k) {
231 case SKF_AD_OFF + SKF_AD_PROTOCOL:
232 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, protocol) != 2);
233
234 /* A = *(u16 *) (CTX + offsetof(protocol)) */
235 *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
236 offsetof(struct sk_buff, protocol));
237 /* A = ntohs(A) [emitting a nop or swap16] */
238 *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
239 break;
240
241 case SKF_AD_OFF + SKF_AD_PKTTYPE:
242 cnt = convert_skb_access(SKF_AD_PKTTYPE, BPF_REG_A, BPF_REG_CTX, insn);
243 insn += cnt - 1;
244 break;
245
246 case SKF_AD_OFF + SKF_AD_IFINDEX:
247 case SKF_AD_OFF + SKF_AD_HATYPE:
248 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, ifindex) != 4);
249 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, type) != 2);
250
251 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
252 BPF_REG_TMP, BPF_REG_CTX,
253 offsetof(struct sk_buff, dev));
254 /* if (tmp != 0) goto pc + 1 */
255 *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_TMP, 0, 1);
256 *insn++ = BPF_EXIT_INSN();
257 if (fp->k == SKF_AD_OFF + SKF_AD_IFINDEX)
258 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_TMP,
259 offsetof(struct net_device, ifindex));
260 else
261 *insn = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_TMP,
262 offsetof(struct net_device, type));
263 break;
264
265 case SKF_AD_OFF + SKF_AD_MARK:
266 cnt = convert_skb_access(SKF_AD_MARK, BPF_REG_A, BPF_REG_CTX, insn);
267 insn += cnt - 1;
268 break;
269
270 case SKF_AD_OFF + SKF_AD_RXHASH:
271 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, hash) != 4);
272
273 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX,
274 offsetof(struct sk_buff, hash));
275 break;
276
277 case SKF_AD_OFF + SKF_AD_QUEUE:
278 cnt = convert_skb_access(SKF_AD_QUEUE, BPF_REG_A, BPF_REG_CTX, insn);
279 insn += cnt - 1;
280 break;
281
282 case SKF_AD_OFF + SKF_AD_VLAN_TAG:
283 cnt = convert_skb_access(SKF_AD_VLAN_TAG,
284 BPF_REG_A, BPF_REG_CTX, insn);
285 insn += cnt - 1;
286 break;
287
288 case SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT:
289 cnt = convert_skb_access(SKF_AD_VLAN_TAG_PRESENT,
290 BPF_REG_A, BPF_REG_CTX, insn);
291 insn += cnt - 1;
292 break;
293
294 case SKF_AD_OFF + SKF_AD_VLAN_TPID:
295 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_proto) != 2);
296
297 /* A = *(u16 *) (CTX + offsetof(vlan_proto)) */
298 *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
299 offsetof(struct sk_buff, vlan_proto));
300 /* A = ntohs(A) [emitting a nop or swap16] */
301 *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
302 break;
303
304 case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
305 case SKF_AD_OFF + SKF_AD_NLATTR:
306 case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
307 case SKF_AD_OFF + SKF_AD_CPU:
308 case SKF_AD_OFF + SKF_AD_RANDOM:
309 /* arg1 = CTX */
310 *insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
311 /* arg2 = A */
312 *insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_A);
313 /* arg3 = X */
314 *insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_X);
315 /* Emit call(arg1=CTX, arg2=A, arg3=X) */
316 switch (fp->k) {
317 case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
318 *insn = BPF_EMIT_CALL(__skb_get_pay_offset);
319 break;
320 case SKF_AD_OFF + SKF_AD_NLATTR:
321 *insn = BPF_EMIT_CALL(__skb_get_nlattr);
322 break;
323 case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
324 *insn = BPF_EMIT_CALL(__skb_get_nlattr_nest);
325 break;
326 case SKF_AD_OFF + SKF_AD_CPU:
327 *insn = BPF_EMIT_CALL(__get_raw_cpu_id);
328 break;
329 case SKF_AD_OFF + SKF_AD_RANDOM:
330 *insn = BPF_EMIT_CALL(bpf_user_rnd_u32);
331 bpf_user_rnd_init_once();
332 break;
333 }
334 break;
335
336 case SKF_AD_OFF + SKF_AD_ALU_XOR_X:
337 /* A ^= X */
338 *insn = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_X);
339 break;
340
341 default:
342 /* This is just a dummy call to avoid letting the compiler
343 * evict __bpf_call_base() as an optimization. Placed here
344 * where no-one bothers.
345 */
346 BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0);
347 return false;
348 }
349
350 *insnp = insn;
351 return true;
352 }
353
354 /**
355 * bpf_convert_filter - convert filter program
356 * @prog: the user passed filter program
357 * @len: the length of the user passed filter program
358 * @new_prog: allocated 'struct bpf_prog' or NULL
359 * @new_len: pointer to store length of converted program
360 *
361 * Remap 'sock_filter' style classic BPF (cBPF) instruction set to 'bpf_insn'
362 * style extended BPF (eBPF).
363 * Conversion workflow:
364 *
365 * 1) First pass for calculating the new program length:
366 * bpf_convert_filter(old_prog, old_len, NULL, &new_len)
367 *
368 * 2) 2nd pass to remap in two passes: 1st pass finds new
369 * jump offsets, 2nd pass remapping:
370 * bpf_convert_filter(old_prog, old_len, new_prog, &new_len);
371 */
372 static int bpf_convert_filter(struct sock_filter *prog, int len,
373 struct bpf_prog *new_prog, int *new_len)
374 {
375 int new_flen = 0, pass = 0, target, i, stack_off;
376 struct bpf_insn *new_insn, *first_insn = NULL;
377 struct sock_filter *fp;
378 int *addrs = NULL;
379 u8 bpf_src;
380
381 BUILD_BUG_ON(BPF_MEMWORDS * sizeof(u32) > MAX_BPF_STACK);
382 BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG);
383
384 if (len <= 0 || len > BPF_MAXINSNS)
385 return -EINVAL;
386
387 if (new_prog) {
388 first_insn = new_prog->insnsi;
389 addrs = kcalloc(len, sizeof(*addrs),
390 GFP_KERNEL | __GFP_NOWARN);
391 if (!addrs)
392 return -ENOMEM;
393 }
394
395 do_pass:
396 new_insn = first_insn;
397 fp = prog;
398
399 /* Classic BPF related prologue emission. */
400 if (new_prog) {
401 /* Classic BPF expects A and X to be reset first. These need
402 * to be guaranteed to be the first two instructions.
403 */
404 *new_insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
405 *new_insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_X, BPF_REG_X);
406
407 /* All programs must keep CTX in callee saved BPF_REG_CTX.
408 * In eBPF case it's done by the compiler, here we need to
409 * do this ourself. Initial CTX is present in BPF_REG_ARG1.
410 */
411 *new_insn++ = BPF_MOV64_REG(BPF_REG_CTX, BPF_REG_ARG1);
412 } else {
413 new_insn += 3;
414 }
415
416 for (i = 0; i < len; fp++, i++) {
417 struct bpf_insn tmp_insns[6] = { };
418 struct bpf_insn *insn = tmp_insns;
419
420 if (addrs)
421 addrs[i] = new_insn - first_insn;
422
423 switch (fp->code) {
424 /* All arithmetic insns and skb loads map as-is. */
425 case BPF_ALU | BPF_ADD | BPF_X:
426 case BPF_ALU | BPF_ADD | BPF_K:
427 case BPF_ALU | BPF_SUB | BPF_X:
428 case BPF_ALU | BPF_SUB | BPF_K:
429 case BPF_ALU | BPF_AND | BPF_X:
430 case BPF_ALU | BPF_AND | BPF_K:
431 case BPF_ALU | BPF_OR | BPF_X:
432 case BPF_ALU | BPF_OR | BPF_K:
433 case BPF_ALU | BPF_LSH | BPF_X:
434 case BPF_ALU | BPF_LSH | BPF_K:
435 case BPF_ALU | BPF_RSH | BPF_X:
436 case BPF_ALU | BPF_RSH | BPF_K:
437 case BPF_ALU | BPF_XOR | BPF_X:
438 case BPF_ALU | BPF_XOR | BPF_K:
439 case BPF_ALU | BPF_MUL | BPF_X:
440 case BPF_ALU | BPF_MUL | BPF_K:
441 case BPF_ALU | BPF_DIV | BPF_X:
442 case BPF_ALU | BPF_DIV | BPF_K:
443 case BPF_ALU | BPF_MOD | BPF_X:
444 case BPF_ALU | BPF_MOD | BPF_K:
445 case BPF_ALU | BPF_NEG:
446 case BPF_LD | BPF_ABS | BPF_W:
447 case BPF_LD | BPF_ABS | BPF_H:
448 case BPF_LD | BPF_ABS | BPF_B:
449 case BPF_LD | BPF_IND | BPF_W:
450 case BPF_LD | BPF_IND | BPF_H:
451 case BPF_LD | BPF_IND | BPF_B:
452 /* Check for overloaded BPF extension and
453 * directly convert it if found, otherwise
454 * just move on with mapping.
455 */
456 if (BPF_CLASS(fp->code) == BPF_LD &&
457 BPF_MODE(fp->code) == BPF_ABS &&
458 convert_bpf_extensions(fp, &insn))
459 break;
460
461 if (fp->code == (BPF_ALU | BPF_DIV | BPF_X) ||
462 fp->code == (BPF_ALU | BPF_MOD | BPF_X))
463 *insn++ = BPF_MOV32_REG(BPF_REG_X, BPF_REG_X);
464
465 *insn = BPF_RAW_INSN(fp->code, BPF_REG_A, BPF_REG_X, 0, fp->k);
466 break;
467
468 /* Jump transformation cannot use BPF block macros
469 * everywhere as offset calculation and target updates
470 * require a bit more work than the rest, i.e. jump
471 * opcodes map as-is, but offsets need adjustment.
472 */
473
474 #define BPF_EMIT_JMP \
475 do { \
476 if (target >= len || target < 0) \
477 goto err; \
478 insn->off = addrs ? addrs[target] - addrs[i] - 1 : 0; \
479 /* Adjust pc relative offset for 2nd or 3rd insn. */ \
480 insn->off -= insn - tmp_insns; \
481 } while (0)
482
483 case BPF_JMP | BPF_JA:
484 target = i + fp->k + 1;
485 insn->code = fp->code;
486 BPF_EMIT_JMP;
487 break;
488
489 case BPF_JMP | BPF_JEQ | BPF_K:
490 case BPF_JMP | BPF_JEQ | BPF_X:
491 case BPF_JMP | BPF_JSET | BPF_K:
492 case BPF_JMP | BPF_JSET | BPF_X:
493 case BPF_JMP | BPF_JGT | BPF_K:
494 case BPF_JMP | BPF_JGT | BPF_X:
495 case BPF_JMP | BPF_JGE | BPF_K:
496 case BPF_JMP | BPF_JGE | BPF_X:
497 if (BPF_SRC(fp->code) == BPF_K && (int) fp->k < 0) {
498 /* BPF immediates are signed, zero extend
499 * immediate into tmp register and use it
500 * in compare insn.
501 */
502 *insn++ = BPF_MOV32_IMM(BPF_REG_TMP, fp->k);
503
504 insn->dst_reg = BPF_REG_A;
505 insn->src_reg = BPF_REG_TMP;
506 bpf_src = BPF_X;
507 } else {
508 insn->dst_reg = BPF_REG_A;
509 insn->imm = fp->k;
510 bpf_src = BPF_SRC(fp->code);
511 insn->src_reg = bpf_src == BPF_X ? BPF_REG_X : 0;
512 }
513
514 /* Common case where 'jump_false' is next insn. */
515 if (fp->jf == 0) {
516 insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
517 target = i + fp->jt + 1;
518 BPF_EMIT_JMP;
519 break;
520 }
521
522 /* Convert some jumps when 'jump_true' is next insn. */
523 if (fp->jt == 0) {
524 switch (BPF_OP(fp->code)) {
525 case BPF_JEQ:
526 insn->code = BPF_JMP | BPF_JNE | bpf_src;
527 break;
528 case BPF_JGT:
529 insn->code = BPF_JMP | BPF_JLE | bpf_src;
530 break;
531 case BPF_JGE:
532 insn->code = BPF_JMP | BPF_JLT | bpf_src;
533 break;
534 default:
535 goto jmp_rest;
536 }
537
538 target = i + fp->jf + 1;
539 BPF_EMIT_JMP;
540 break;
541 }
542 jmp_rest:
543 /* Other jumps are mapped into two insns: Jxx and JA. */
544 target = i + fp->jt + 1;
545 insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
546 BPF_EMIT_JMP;
547 insn++;
548
549 insn->code = BPF_JMP | BPF_JA;
550 target = i + fp->jf + 1;
551 BPF_EMIT_JMP;
552 break;
553
554 /* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */
555 case BPF_LDX | BPF_MSH | BPF_B:
556 /* tmp = A */
557 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_A);
558 /* A = BPF_R0 = *(u8 *) (skb->data + K) */
559 *insn++ = BPF_LD_ABS(BPF_B, fp->k);
560 /* A &= 0xf */
561 *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, 0xf);
562 /* A <<= 2 */
563 *insn++ = BPF_ALU32_IMM(BPF_LSH, BPF_REG_A, 2);
564 /* X = A */
565 *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
566 /* A = tmp */
567 *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_TMP);
568 break;
569
570 /* RET_K is remaped into 2 insns. RET_A case doesn't need an
571 * extra mov as BPF_REG_0 is already mapped into BPF_REG_A.
572 */
573 case BPF_RET | BPF_A:
574 case BPF_RET | BPF_K:
575 if (BPF_RVAL(fp->code) == BPF_K)
576 *insn++ = BPF_MOV32_RAW(BPF_K, BPF_REG_0,
577 0, fp->k);
578 *insn = BPF_EXIT_INSN();
579 break;
580
581 /* Store to stack. */
582 case BPF_ST:
583 case BPF_STX:
584 stack_off = fp->k * 4 + 4;
585 *insn = BPF_STX_MEM(BPF_W, BPF_REG_FP, BPF_CLASS(fp->code) ==
586 BPF_ST ? BPF_REG_A : BPF_REG_X,
587 -stack_off);
588 /* check_load_and_stores() verifies that classic BPF can
589 * load from stack only after write, so tracking
590 * stack_depth for ST|STX insns is enough
591 */
592 if (new_prog && new_prog->aux->stack_depth < stack_off)
593 new_prog->aux->stack_depth = stack_off;
594 break;
595
596 /* Load from stack. */
597 case BPF_LD | BPF_MEM:
598 case BPF_LDX | BPF_MEM:
599 stack_off = fp->k * 4 + 4;
600 *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
601 BPF_REG_A : BPF_REG_X, BPF_REG_FP,
602 -stack_off);
603 break;
604
605 /* A = K or X = K */
606 case BPF_LD | BPF_IMM:
607 case BPF_LDX | BPF_IMM:
608 *insn = BPF_MOV32_IMM(BPF_CLASS(fp->code) == BPF_LD ?
609 BPF_REG_A : BPF_REG_X, fp->k);
610 break;
611
612 /* X = A */
613 case BPF_MISC | BPF_TAX:
614 *insn = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
615 break;
616
617 /* A = X */
618 case BPF_MISC | BPF_TXA:
619 *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_X);
620 break;
621
622 /* A = skb->len or X = skb->len */
623 case BPF_LD | BPF_W | BPF_LEN:
624 case BPF_LDX | BPF_W | BPF_LEN:
625 *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
626 BPF_REG_A : BPF_REG_X, BPF_REG_CTX,
627 offsetof(struct sk_buff, len));
628 break;
629
630 /* Access seccomp_data fields. */
631 case BPF_LDX | BPF_ABS | BPF_W:
632 /* A = *(u32 *) (ctx + K) */
633 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, fp->k);
634 break;
635
636 /* Unknown instruction. */
637 default:
638 goto err;
639 }
640
641 insn++;
642 if (new_prog)
643 memcpy(new_insn, tmp_insns,
644 sizeof(*insn) * (insn - tmp_insns));
645 new_insn += insn - tmp_insns;
646 }
647
648 if (!new_prog) {
649 /* Only calculating new length. */
650 *new_len = new_insn - first_insn;
651 return 0;
652 }
653
654 pass++;
655 if (new_flen != new_insn - first_insn) {
656 new_flen = new_insn - first_insn;
657 if (pass > 2)
658 goto err;
659 goto do_pass;
660 }
661
662 kfree(addrs);
663 BUG_ON(*new_len != new_flen);
664 return 0;
665 err:
666 kfree(addrs);
667 return -EINVAL;
668 }
669
670 /* Security:
671 *
672 * As we dont want to clear mem[] array for each packet going through
673 * __bpf_prog_run(), we check that filter loaded by user never try to read
674 * a cell if not previously written, and we check all branches to be sure
675 * a malicious user doesn't try to abuse us.
676 */
677 static int check_load_and_stores(const struct sock_filter *filter, int flen)
678 {
679 u16 *masks, memvalid = 0; /* One bit per cell, 16 cells */
680 int pc, ret = 0;
681
682 BUILD_BUG_ON(BPF_MEMWORDS > 16);
683
684 masks = kmalloc_array(flen, sizeof(*masks), GFP_KERNEL);
685 if (!masks)
686 return -ENOMEM;
687
688 memset(masks, 0xff, flen * sizeof(*masks));
689
690 for (pc = 0; pc < flen; pc++) {
691 memvalid &= masks[pc];
692
693 switch (filter[pc].code) {
694 case BPF_ST:
695 case BPF_STX:
696 memvalid |= (1 << filter[pc].k);
697 break;
698 case BPF_LD | BPF_MEM:
699 case BPF_LDX | BPF_MEM:
700 if (!(memvalid & (1 << filter[pc].k))) {
701 ret = -EINVAL;
702 goto error;
703 }
704 break;
705 case BPF_JMP | BPF_JA:
706 /* A jump must set masks on target */
707 masks[pc + 1 + filter[pc].k] &= memvalid;
708 memvalid = ~0;
709 break;
710 case BPF_JMP | BPF_JEQ | BPF_K:
711 case BPF_JMP | BPF_JEQ | BPF_X:
712 case BPF_JMP | BPF_JGE | BPF_K:
713 case BPF_JMP | BPF_JGE | BPF_X:
714 case BPF_JMP | BPF_JGT | BPF_K:
715 case BPF_JMP | BPF_JGT | BPF_X:
716 case BPF_JMP | BPF_JSET | BPF_K:
717 case BPF_JMP | BPF_JSET | BPF_X:
718 /* A jump must set masks on targets */
719 masks[pc + 1 + filter[pc].jt] &= memvalid;
720 masks[pc + 1 + filter[pc].jf] &= memvalid;
721 memvalid = ~0;
722 break;
723 }
724 }
725 error:
726 kfree(masks);
727 return ret;
728 }
729
730 static bool chk_code_allowed(u16 code_to_probe)
731 {
732 static const bool codes[] = {
733 /* 32 bit ALU operations */
734 [BPF_ALU | BPF_ADD | BPF_K] = true,
735 [BPF_ALU | BPF_ADD | BPF_X] = true,
736 [BPF_ALU | BPF_SUB | BPF_K] = true,
737 [BPF_ALU | BPF_SUB | BPF_X] = true,
738 [BPF_ALU | BPF_MUL | BPF_K] = true,
739 [BPF_ALU | BPF_MUL | BPF_X] = true,
740 [BPF_ALU | BPF_DIV | BPF_K] = true,
741 [BPF_ALU | BPF_DIV | BPF_X] = true,
742 [BPF_ALU | BPF_MOD | BPF_K] = true,
743 [BPF_ALU | BPF_MOD | BPF_X] = true,
744 [BPF_ALU | BPF_AND | BPF_K] = true,
745 [BPF_ALU | BPF_AND | BPF_X] = true,
746 [BPF_ALU | BPF_OR | BPF_K] = true,
747 [BPF_ALU | BPF_OR | BPF_X] = true,
748 [BPF_ALU | BPF_XOR | BPF_K] = true,
749 [BPF_ALU | BPF_XOR | BPF_X] = true,
750 [BPF_ALU | BPF_LSH | BPF_K] = true,
751 [BPF_ALU | BPF_LSH | BPF_X] = true,
752 [BPF_ALU | BPF_RSH | BPF_K] = true,
753 [BPF_ALU | BPF_RSH | BPF_X] = true,
754 [BPF_ALU | BPF_NEG] = true,
755 /* Load instructions */
756 [BPF_LD | BPF_W | BPF_ABS] = true,
757 [BPF_LD | BPF_H | BPF_ABS] = true,
758 [BPF_LD | BPF_B | BPF_ABS] = true,
759 [BPF_LD | BPF_W | BPF_LEN] = true,
760 [BPF_LD | BPF_W | BPF_IND] = true,
761 [BPF_LD | BPF_H | BPF_IND] = true,
762 [BPF_LD | BPF_B | BPF_IND] = true,
763 [BPF_LD | BPF_IMM] = true,
764 [BPF_LD | BPF_MEM] = true,
765 [BPF_LDX | BPF_W | BPF_LEN] = true,
766 [BPF_LDX | BPF_B | BPF_MSH] = true,
767 [BPF_LDX | BPF_IMM] = true,
768 [BPF_LDX | BPF_MEM] = true,
769 /* Store instructions */
770 [BPF_ST] = true,
771 [BPF_STX] = true,
772 /* Misc instructions */
773 [BPF_MISC | BPF_TAX] = true,
774 [BPF_MISC | BPF_TXA] = true,
775 /* Return instructions */
776 [BPF_RET | BPF_K] = true,
777 [BPF_RET | BPF_A] = true,
778 /* Jump instructions */
779 [BPF_JMP | BPF_JA] = true,
780 [BPF_JMP | BPF_JEQ | BPF_K] = true,
781 [BPF_JMP | BPF_JEQ | BPF_X] = true,
782 [BPF_JMP | BPF_JGE | BPF_K] = true,
783 [BPF_JMP | BPF_JGE | BPF_X] = true,
784 [BPF_JMP | BPF_JGT | BPF_K] = true,
785 [BPF_JMP | BPF_JGT | BPF_X] = true,
786 [BPF_JMP | BPF_JSET | BPF_K] = true,
787 [BPF_JMP | BPF_JSET | BPF_X] = true,
788 };
789
790 if (code_to_probe >= ARRAY_SIZE(codes))
791 return false;
792
793 return codes[code_to_probe];
794 }
795
796 static bool bpf_check_basics_ok(const struct sock_filter *filter,
797 unsigned int flen)
798 {
799 if (filter == NULL)
800 return false;
801 if (flen == 0 || flen > BPF_MAXINSNS)
802 return false;
803
804 return true;
805 }
806
807 /**
808 * bpf_check_classic - verify socket filter code
809 * @filter: filter to verify
810 * @flen: length of filter
811 *
812 * Check the user's filter code. If we let some ugly
813 * filter code slip through kaboom! The filter must contain
814 * no references or jumps that are out of range, no illegal
815 * instructions, and must end with a RET instruction.
816 *
817 * All jumps are forward as they are not signed.
818 *
819 * Returns 0 if the rule set is legal or -EINVAL if not.
820 */
821 static int bpf_check_classic(const struct sock_filter *filter,
822 unsigned int flen)
823 {
824 bool anc_found;
825 int pc;
826
827 /* Check the filter code now */
828 for (pc = 0; pc < flen; pc++) {
829 const struct sock_filter *ftest = &filter[pc];
830
831 /* May we actually operate on this code? */
832 if (!chk_code_allowed(ftest->code))
833 return -EINVAL;
834
835 /* Some instructions need special checks */
836 switch (ftest->code) {
837 case BPF_ALU | BPF_DIV | BPF_K:
838 case BPF_ALU | BPF_MOD | BPF_K:
839 /* Check for division by zero */
840 if (ftest->k == 0)
841 return -EINVAL;
842 break;
843 case BPF_ALU | BPF_LSH | BPF_K:
844 case BPF_ALU | BPF_RSH | BPF_K:
845 if (ftest->k >= 32)
846 return -EINVAL;
847 break;
848 case BPF_LD | BPF_MEM:
849 case BPF_LDX | BPF_MEM:
850 case BPF_ST:
851 case BPF_STX:
852 /* Check for invalid memory addresses */
853 if (ftest->k >= BPF_MEMWORDS)
854 return -EINVAL;
855 break;
856 case BPF_JMP | BPF_JA:
857 /* Note, the large ftest->k might cause loops.
858 * Compare this with conditional jumps below,
859 * where offsets are limited. --ANK (981016)
860 */
861 if (ftest->k >= (unsigned int)(flen - pc - 1))
862 return -EINVAL;
863 break;
864 case BPF_JMP | BPF_JEQ | BPF_K:
865 case BPF_JMP | BPF_JEQ | BPF_X:
866 case BPF_JMP | BPF_JGE | BPF_K:
867 case BPF_JMP | BPF_JGE | BPF_X:
868 case BPF_JMP | BPF_JGT | BPF_K:
869 case BPF_JMP | BPF_JGT | BPF_X:
870 case BPF_JMP | BPF_JSET | BPF_K:
871 case BPF_JMP | BPF_JSET | BPF_X:
872 /* Both conditionals must be safe */
873 if (pc + ftest->jt + 1 >= flen ||
874 pc + ftest->jf + 1 >= flen)
875 return -EINVAL;
876 break;
877 case BPF_LD | BPF_W | BPF_ABS:
878 case BPF_LD | BPF_H | BPF_ABS:
879 case BPF_LD | BPF_B | BPF_ABS:
880 anc_found = false;
881 if (bpf_anc_helper(ftest) & BPF_ANC)
882 anc_found = true;
883 /* Ancillary operation unknown or unsupported */
884 if (anc_found == false && ftest->k >= SKF_AD_OFF)
885 return -EINVAL;
886 }
887 }
888
889 /* Last instruction must be a RET code */
890 switch (filter[flen - 1].code) {
891 case BPF_RET | BPF_K:
892 case BPF_RET | BPF_A:
893 return check_load_and_stores(filter, flen);
894 }
895
896 return -EINVAL;
897 }
898
899 static int bpf_prog_store_orig_filter(struct bpf_prog *fp,
900 const struct sock_fprog *fprog)
901 {
902 unsigned int fsize = bpf_classic_proglen(fprog);
903 struct sock_fprog_kern *fkprog;
904
905 fp->orig_prog = kmalloc(sizeof(*fkprog), GFP_KERNEL);
906 if (!fp->orig_prog)
907 return -ENOMEM;
908
909 fkprog = fp->orig_prog;
910 fkprog->len = fprog->len;
911
912 fkprog->filter = kmemdup(fp->insns, fsize,
913 GFP_KERNEL | __GFP_NOWARN);
914 if (!fkprog->filter) {
915 kfree(fp->orig_prog);
916 return -ENOMEM;
917 }
918
919 return 0;
920 }
921
922 static void bpf_release_orig_filter(struct bpf_prog *fp)
923 {
924 struct sock_fprog_kern *fprog = fp->orig_prog;
925
926 if (fprog) {
927 kfree(fprog->filter);
928 kfree(fprog);
929 }
930 }
931
932 static void __bpf_prog_release(struct bpf_prog *prog)
933 {
934 if (prog->type == BPF_PROG_TYPE_SOCKET_FILTER) {
935 bpf_prog_put(prog);
936 } else {
937 bpf_release_orig_filter(prog);
938 bpf_prog_free(prog);
939 }
940 }
941
942 static void __sk_filter_release(struct sk_filter *fp)
943 {
944 __bpf_prog_release(fp->prog);
945 kfree(fp);
946 }
947
948 /**
949 * sk_filter_release_rcu - Release a socket filter by rcu_head
950 * @rcu: rcu_head that contains the sk_filter to free
951 */
952 static void sk_filter_release_rcu(struct rcu_head *rcu)
953 {
954 struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu);
955
956 __sk_filter_release(fp);
957 }
958
959 /**
960 * sk_filter_release - release a socket filter
961 * @fp: filter to remove
962 *
963 * Remove a filter from a socket and release its resources.
964 */
965 static void sk_filter_release(struct sk_filter *fp)
966 {
967 if (refcount_dec_and_test(&fp->refcnt))
968 call_rcu(&fp->rcu, sk_filter_release_rcu);
969 }
970
971 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
972 {
973 u32 filter_size = bpf_prog_size(fp->prog->len);
974
975 atomic_sub(filter_size, &sk->sk_omem_alloc);
976 sk_filter_release(fp);
977 }
978
979 /* try to charge the socket memory if there is space available
980 * return true on success
981 */
982 static bool __sk_filter_charge(struct sock *sk, struct sk_filter *fp)
983 {
984 u32 filter_size = bpf_prog_size(fp->prog->len);
985
986 /* same check as in sock_kmalloc() */
987 if (filter_size <= sysctl_optmem_max &&
988 atomic_read(&sk->sk_omem_alloc) + filter_size < sysctl_optmem_max) {
989 atomic_add(filter_size, &sk->sk_omem_alloc);
990 return true;
991 }
992 return false;
993 }
994
995 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp)
996 {
997 if (!refcount_inc_not_zero(&fp->refcnt))
998 return false;
999
1000 if (!__sk_filter_charge(sk, fp)) {
1001 sk_filter_release(fp);
1002 return false;
1003 }
1004 return true;
1005 }
1006
1007 static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp)
1008 {
1009 struct sock_filter *old_prog;
1010 struct bpf_prog *old_fp;
1011 int err, new_len, old_len = fp->len;
1012
1013 /* We are free to overwrite insns et al right here as it
1014 * won't be used at this point in time anymore internally
1015 * after the migration to the internal BPF instruction
1016 * representation.
1017 */
1018 BUILD_BUG_ON(sizeof(struct sock_filter) !=
1019 sizeof(struct bpf_insn));
1020
1021 /* Conversion cannot happen on overlapping memory areas,
1022 * so we need to keep the user BPF around until the 2nd
1023 * pass. At this time, the user BPF is stored in fp->insns.
1024 */
1025 old_prog = kmemdup(fp->insns, old_len * sizeof(struct sock_filter),
1026 GFP_KERNEL | __GFP_NOWARN);
1027 if (!old_prog) {
1028 err = -ENOMEM;
1029 goto out_err;
1030 }
1031
1032 /* 1st pass: calculate the new program length. */
1033 err = bpf_convert_filter(old_prog, old_len, NULL, &new_len);
1034 if (err)
1035 goto out_err_free;
1036
1037 /* Expand fp for appending the new filter representation. */
1038 old_fp = fp;
1039 fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0);
1040 if (!fp) {
1041 /* The old_fp is still around in case we couldn't
1042 * allocate new memory, so uncharge on that one.
1043 */
1044 fp = old_fp;
1045 err = -ENOMEM;
1046 goto out_err_free;
1047 }
1048
1049 fp->len = new_len;
1050
1051 /* 2nd pass: remap sock_filter insns into bpf_insn insns. */
1052 err = bpf_convert_filter(old_prog, old_len, fp, &new_len);
1053 if (err)
1054 /* 2nd bpf_convert_filter() can fail only if it fails
1055 * to allocate memory, remapping must succeed. Note,
1056 * that at this time old_fp has already been released
1057 * by krealloc().
1058 */
1059 goto out_err_free;
1060
1061 fp = bpf_prog_select_runtime(fp, &err);
1062 if (err)
1063 goto out_err_free;
1064
1065 kfree(old_prog);
1066 return fp;
1067
1068 out_err_free:
1069 kfree(old_prog);
1070 out_err:
1071 __bpf_prog_release(fp);
1072 return ERR_PTR(err);
1073 }
1074
1075 static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp,
1076 bpf_aux_classic_check_t trans)
1077 {
1078 int err;
1079
1080 fp->bpf_func = NULL;
1081 fp->jited = 0;
1082
1083 err = bpf_check_classic(fp->insns, fp->len);
1084 if (err) {
1085 __bpf_prog_release(fp);
1086 return ERR_PTR(err);
1087 }
1088
1089 /* There might be additional checks and transformations
1090 * needed on classic filters, f.e. in case of seccomp.
1091 */
1092 if (trans) {
1093 err = trans(fp->insns, fp->len);
1094 if (err) {
1095 __bpf_prog_release(fp);
1096 return ERR_PTR(err);
1097 }
1098 }
1099
1100 /* Probe if we can JIT compile the filter and if so, do
1101 * the compilation of the filter.
1102 */
1103 bpf_jit_compile(fp);
1104
1105 /* JIT compiler couldn't process this filter, so do the
1106 * internal BPF translation for the optimized interpreter.
1107 */
1108 if (!fp->jited)
1109 fp = bpf_migrate_filter(fp);
1110
1111 return fp;
1112 }
1113
1114 /**
1115 * bpf_prog_create - create an unattached filter
1116 * @pfp: the unattached filter that is created
1117 * @fprog: the filter program
1118 *
1119 * Create a filter independent of any socket. We first run some
1120 * sanity checks on it to make sure it does not explode on us later.
1121 * If an error occurs or there is insufficient memory for the filter
1122 * a negative errno code is returned. On success the return is zero.
1123 */
1124 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog)
1125 {
1126 unsigned int fsize = bpf_classic_proglen(fprog);
1127 struct bpf_prog *fp;
1128
1129 /* Make sure new filter is there and in the right amounts. */
1130 if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1131 return -EINVAL;
1132
1133 fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1134 if (!fp)
1135 return -ENOMEM;
1136
1137 memcpy(fp->insns, fprog->filter, fsize);
1138
1139 fp->len = fprog->len;
1140 /* Since unattached filters are not copied back to user
1141 * space through sk_get_filter(), we do not need to hold
1142 * a copy here, and can spare us the work.
1143 */
1144 fp->orig_prog = NULL;
1145
1146 /* bpf_prepare_filter() already takes care of freeing
1147 * memory in case something goes wrong.
1148 */
1149 fp = bpf_prepare_filter(fp, NULL);
1150 if (IS_ERR(fp))
1151 return PTR_ERR(fp);
1152
1153 *pfp = fp;
1154 return 0;
1155 }
1156 EXPORT_SYMBOL_GPL(bpf_prog_create);
1157
1158 /**
1159 * bpf_prog_create_from_user - create an unattached filter from user buffer
1160 * @pfp: the unattached filter that is created
1161 * @fprog: the filter program
1162 * @trans: post-classic verifier transformation handler
1163 * @save_orig: save classic BPF program
1164 *
1165 * This function effectively does the same as bpf_prog_create(), only
1166 * that it builds up its insns buffer from user space provided buffer.
1167 * It also allows for passing a bpf_aux_classic_check_t handler.
1168 */
1169 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
1170 bpf_aux_classic_check_t trans, bool save_orig)
1171 {
1172 unsigned int fsize = bpf_classic_proglen(fprog);
1173 struct bpf_prog *fp;
1174 int err;
1175
1176 /* Make sure new filter is there and in the right amounts. */
1177 if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1178 return -EINVAL;
1179
1180 fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1181 if (!fp)
1182 return -ENOMEM;
1183
1184 if (copy_from_user(fp->insns, fprog->filter, fsize)) {
1185 __bpf_prog_free(fp);
1186 return -EFAULT;
1187 }
1188
1189 fp->len = fprog->len;
1190 fp->orig_prog = NULL;
1191
1192 if (save_orig) {
1193 err = bpf_prog_store_orig_filter(fp, fprog);
1194 if (err) {
1195 __bpf_prog_free(fp);
1196 return -ENOMEM;
1197 }
1198 }
1199
1200 /* bpf_prepare_filter() already takes care of freeing
1201 * memory in case something goes wrong.
1202 */
1203 fp = bpf_prepare_filter(fp, trans);
1204 if (IS_ERR(fp))
1205 return PTR_ERR(fp);
1206
1207 *pfp = fp;
1208 return 0;
1209 }
1210 EXPORT_SYMBOL_GPL(bpf_prog_create_from_user);
1211
1212 void bpf_prog_destroy(struct bpf_prog *fp)
1213 {
1214 __bpf_prog_release(fp);
1215 }
1216 EXPORT_SYMBOL_GPL(bpf_prog_destroy);
1217
1218 static int __sk_attach_prog(struct bpf_prog *prog, struct sock *sk)
1219 {
1220 struct sk_filter *fp, *old_fp;
1221
1222 fp = kmalloc(sizeof(*fp), GFP_KERNEL);
1223 if (!fp)
1224 return -ENOMEM;
1225
1226 fp->prog = prog;
1227
1228 if (!__sk_filter_charge(sk, fp)) {
1229 kfree(fp);
1230 return -ENOMEM;
1231 }
1232 refcount_set(&fp->refcnt, 1);
1233
1234 old_fp = rcu_dereference_protected(sk->sk_filter,
1235 lockdep_sock_is_held(sk));
1236 rcu_assign_pointer(sk->sk_filter, fp);
1237
1238 if (old_fp)
1239 sk_filter_uncharge(sk, old_fp);
1240
1241 return 0;
1242 }
1243
1244 static int __reuseport_attach_prog(struct bpf_prog *prog, struct sock *sk)
1245 {
1246 struct bpf_prog *old_prog;
1247 int err;
1248
1249 if (bpf_prog_size(prog->len) > sysctl_optmem_max)
1250 return -ENOMEM;
1251
1252 if (sk_unhashed(sk) && sk->sk_reuseport) {
1253 err = reuseport_alloc(sk);
1254 if (err)
1255 return err;
1256 } else if (!rcu_access_pointer(sk->sk_reuseport_cb)) {
1257 /* The socket wasn't bound with SO_REUSEPORT */
1258 return -EINVAL;
1259 }
1260
1261 old_prog = reuseport_attach_prog(sk, prog);
1262 if (old_prog)
1263 bpf_prog_destroy(old_prog);
1264
1265 return 0;
1266 }
1267
1268 static
1269 struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk)
1270 {
1271 unsigned int fsize = bpf_classic_proglen(fprog);
1272 struct bpf_prog *prog;
1273 int err;
1274
1275 if (sock_flag(sk, SOCK_FILTER_LOCKED))
1276 return ERR_PTR(-EPERM);
1277
1278 /* Make sure new filter is there and in the right amounts. */
1279 if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1280 return ERR_PTR(-EINVAL);
1281
1282 prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1283 if (!prog)
1284 return ERR_PTR(-ENOMEM);
1285
1286 if (copy_from_user(prog->insns, fprog->filter, fsize)) {
1287 __bpf_prog_free(prog);
1288 return ERR_PTR(-EFAULT);
1289 }
1290
1291 prog->len = fprog->len;
1292
1293 err = bpf_prog_store_orig_filter(prog, fprog);
1294 if (err) {
1295 __bpf_prog_free(prog);
1296 return ERR_PTR(-ENOMEM);
1297 }
1298
1299 /* bpf_prepare_filter() already takes care of freeing
1300 * memory in case something goes wrong.
1301 */
1302 return bpf_prepare_filter(prog, NULL);
1303 }
1304
1305 /**
1306 * sk_attach_filter - attach a socket filter
1307 * @fprog: the filter program
1308 * @sk: the socket to use
1309 *
1310 * Attach the user's filter code. We first run some sanity checks on
1311 * it to make sure it does not explode on us later. If an error
1312 * occurs or there is insufficient memory for the filter a negative
1313 * errno code is returned. On success the return is zero.
1314 */
1315 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1316 {
1317 struct bpf_prog *prog = __get_filter(fprog, sk);
1318 int err;
1319
1320 if (IS_ERR(prog))
1321 return PTR_ERR(prog);
1322
1323 err = __sk_attach_prog(prog, sk);
1324 if (err < 0) {
1325 __bpf_prog_release(prog);
1326 return err;
1327 }
1328
1329 return 0;
1330 }
1331 EXPORT_SYMBOL_GPL(sk_attach_filter);
1332
1333 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1334 {
1335 struct bpf_prog *prog = __get_filter(fprog, sk);
1336 int err;
1337
1338 if (IS_ERR(prog))
1339 return PTR_ERR(prog);
1340
1341 err = __reuseport_attach_prog(prog, sk);
1342 if (err < 0) {
1343 __bpf_prog_release(prog);
1344 return err;
1345 }
1346
1347 return 0;
1348 }
1349
1350 static struct bpf_prog *__get_bpf(u32 ufd, struct sock *sk)
1351 {
1352 if (sock_flag(sk, SOCK_FILTER_LOCKED))
1353 return ERR_PTR(-EPERM);
1354
1355 return bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
1356 }
1357
1358 int sk_attach_bpf(u32 ufd, struct sock *sk)
1359 {
1360 struct bpf_prog *prog = __get_bpf(ufd, sk);
1361 int err;
1362
1363 if (IS_ERR(prog))
1364 return PTR_ERR(prog);
1365
1366 err = __sk_attach_prog(prog, sk);
1367 if (err < 0) {
1368 bpf_prog_put(prog);
1369 return err;
1370 }
1371
1372 return 0;
1373 }
1374
1375 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk)
1376 {
1377 struct bpf_prog *prog = __get_bpf(ufd, sk);
1378 int err;
1379
1380 if (IS_ERR(prog))
1381 return PTR_ERR(prog);
1382
1383 err = __reuseport_attach_prog(prog, sk);
1384 if (err < 0) {
1385 bpf_prog_put(prog);
1386 return err;
1387 }
1388
1389 return 0;
1390 }
1391
1392 struct bpf_scratchpad {
1393 union {
1394 __be32 diff[MAX_BPF_STACK / sizeof(__be32)];
1395 u8 buff[MAX_BPF_STACK];
1396 };
1397 };
1398
1399 static DEFINE_PER_CPU(struct bpf_scratchpad, bpf_sp);
1400
1401 static inline int __bpf_try_make_writable(struct sk_buff *skb,
1402 unsigned int write_len)
1403 {
1404 return skb_ensure_writable(skb, write_len);
1405 }
1406
1407 static inline int bpf_try_make_writable(struct sk_buff *skb,
1408 unsigned int write_len)
1409 {
1410 int err = __bpf_try_make_writable(skb, write_len);
1411
1412 bpf_compute_data_pointers(skb);
1413 return err;
1414 }
1415
1416 static int bpf_try_make_head_writable(struct sk_buff *skb)
1417 {
1418 return bpf_try_make_writable(skb, skb_headlen(skb));
1419 }
1420
1421 static inline void bpf_push_mac_rcsum(struct sk_buff *skb)
1422 {
1423 if (skb_at_tc_ingress(skb))
1424 skb_postpush_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1425 }
1426
1427 static inline void bpf_pull_mac_rcsum(struct sk_buff *skb)
1428 {
1429 if (skb_at_tc_ingress(skb))
1430 skb_postpull_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1431 }
1432
1433 BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset,
1434 const void *, from, u32, len, u64, flags)
1435 {
1436 void *ptr;
1437
1438 if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH)))
1439 return -EINVAL;
1440 if (unlikely(offset > 0xffff))
1441 return -EFAULT;
1442 if (unlikely(bpf_try_make_writable(skb, offset + len)))
1443 return -EFAULT;
1444
1445 ptr = skb->data + offset;
1446 if (flags & BPF_F_RECOMPUTE_CSUM)
1447 __skb_postpull_rcsum(skb, ptr, len, offset);
1448
1449 memcpy(ptr, from, len);
1450
1451 if (flags & BPF_F_RECOMPUTE_CSUM)
1452 __skb_postpush_rcsum(skb, ptr, len, offset);
1453 if (flags & BPF_F_INVALIDATE_HASH)
1454 skb_clear_hash(skb);
1455
1456 return 0;
1457 }
1458
1459 static const struct bpf_func_proto bpf_skb_store_bytes_proto = {
1460 .func = bpf_skb_store_bytes,
1461 .gpl_only = false,
1462 .ret_type = RET_INTEGER,
1463 .arg1_type = ARG_PTR_TO_CTX,
1464 .arg2_type = ARG_ANYTHING,
1465 .arg3_type = ARG_PTR_TO_MEM,
1466 .arg4_type = ARG_CONST_SIZE,
1467 .arg5_type = ARG_ANYTHING,
1468 };
1469
1470 BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset,
1471 void *, to, u32, len)
1472 {
1473 void *ptr;
1474
1475 if (unlikely(offset > 0xffff))
1476 goto err_clear;
1477
1478 ptr = skb_header_pointer(skb, offset, len, to);
1479 if (unlikely(!ptr))
1480 goto err_clear;
1481 if (ptr != to)
1482 memcpy(to, ptr, len);
1483
1484 return 0;
1485 err_clear:
1486 memset(to, 0, len);
1487 return -EFAULT;
1488 }
1489
1490 static const struct bpf_func_proto bpf_skb_load_bytes_proto = {
1491 .func = bpf_skb_load_bytes,
1492 .gpl_only = false,
1493 .ret_type = RET_INTEGER,
1494 .arg1_type = ARG_PTR_TO_CTX,
1495 .arg2_type = ARG_ANYTHING,
1496 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
1497 .arg4_type = ARG_CONST_SIZE,
1498 };
1499
1500 BPF_CALL_2(bpf_skb_pull_data, struct sk_buff *, skb, u32, len)
1501 {
1502 /* Idea is the following: should the needed direct read/write
1503 * test fail during runtime, we can pull in more data and redo
1504 * again, since implicitly, we invalidate previous checks here.
1505 *
1506 * Or, since we know how much we need to make read/writeable,
1507 * this can be done once at the program beginning for direct
1508 * access case. By this we overcome limitations of only current
1509 * headroom being accessible.
1510 */
1511 return bpf_try_make_writable(skb, len ? : skb_headlen(skb));
1512 }
1513
1514 static const struct bpf_func_proto bpf_skb_pull_data_proto = {
1515 .func = bpf_skb_pull_data,
1516 .gpl_only = false,
1517 .ret_type = RET_INTEGER,
1518 .arg1_type = ARG_PTR_TO_CTX,
1519 .arg2_type = ARG_ANYTHING,
1520 };
1521
1522 BPF_CALL_5(bpf_l3_csum_replace, struct sk_buff *, skb, u32, offset,
1523 u64, from, u64, to, u64, flags)
1524 {
1525 __sum16 *ptr;
1526
1527 if (unlikely(flags & ~(BPF_F_HDR_FIELD_MASK)))
1528 return -EINVAL;
1529 if (unlikely(offset > 0xffff || offset & 1))
1530 return -EFAULT;
1531 if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1532 return -EFAULT;
1533
1534 ptr = (__sum16 *)(skb->data + offset);
1535 switch (flags & BPF_F_HDR_FIELD_MASK) {
1536 case 0:
1537 if (unlikely(from != 0))
1538 return -EINVAL;
1539
1540 csum_replace_by_diff(ptr, to);
1541 break;
1542 case 2:
1543 csum_replace2(ptr, from, to);
1544 break;
1545 case 4:
1546 csum_replace4(ptr, from, to);
1547 break;
1548 default:
1549 return -EINVAL;
1550 }
1551
1552 return 0;
1553 }
1554
1555 static const struct bpf_func_proto bpf_l3_csum_replace_proto = {
1556 .func = bpf_l3_csum_replace,
1557 .gpl_only = false,
1558 .ret_type = RET_INTEGER,
1559 .arg1_type = ARG_PTR_TO_CTX,
1560 .arg2_type = ARG_ANYTHING,
1561 .arg3_type = ARG_ANYTHING,
1562 .arg4_type = ARG_ANYTHING,
1563 .arg5_type = ARG_ANYTHING,
1564 };
1565
1566 BPF_CALL_5(bpf_l4_csum_replace, struct sk_buff *, skb, u32, offset,
1567 u64, from, u64, to, u64, flags)
1568 {
1569 bool is_pseudo = flags & BPF_F_PSEUDO_HDR;
1570 bool is_mmzero = flags & BPF_F_MARK_MANGLED_0;
1571 bool do_mforce = flags & BPF_F_MARK_ENFORCE;
1572 __sum16 *ptr;
1573
1574 if (unlikely(flags & ~(BPF_F_MARK_MANGLED_0 | BPF_F_MARK_ENFORCE |
1575 BPF_F_PSEUDO_HDR | BPF_F_HDR_FIELD_MASK)))
1576 return -EINVAL;
1577 if (unlikely(offset > 0xffff || offset & 1))
1578 return -EFAULT;
1579 if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1580 return -EFAULT;
1581
1582 ptr = (__sum16 *)(skb->data + offset);
1583 if (is_mmzero && !do_mforce && !*ptr)
1584 return 0;
1585
1586 switch (flags & BPF_F_HDR_FIELD_MASK) {
1587 case 0:
1588 if (unlikely(from != 0))
1589 return -EINVAL;
1590
1591 inet_proto_csum_replace_by_diff(ptr, skb, to, is_pseudo);
1592 break;
1593 case 2:
1594 inet_proto_csum_replace2(ptr, skb, from, to, is_pseudo);
1595 break;
1596 case 4:
1597 inet_proto_csum_replace4(ptr, skb, from, to, is_pseudo);
1598 break;
1599 default:
1600 return -EINVAL;
1601 }
1602
1603 if (is_mmzero && !*ptr)
1604 *ptr = CSUM_MANGLED_0;
1605 return 0;
1606 }
1607
1608 static const struct bpf_func_proto bpf_l4_csum_replace_proto = {
1609 .func = bpf_l4_csum_replace,
1610 .gpl_only = false,
1611 .ret_type = RET_INTEGER,
1612 .arg1_type = ARG_PTR_TO_CTX,
1613 .arg2_type = ARG_ANYTHING,
1614 .arg3_type = ARG_ANYTHING,
1615 .arg4_type = ARG_ANYTHING,
1616 .arg5_type = ARG_ANYTHING,
1617 };
1618
1619 BPF_CALL_5(bpf_csum_diff, __be32 *, from, u32, from_size,
1620 __be32 *, to, u32, to_size, __wsum, seed)
1621 {
1622 struct bpf_scratchpad *sp = this_cpu_ptr(&bpf_sp);
1623 u32 diff_size = from_size + to_size;
1624 int i, j = 0;
1625
1626 /* This is quite flexible, some examples:
1627 *
1628 * from_size == 0, to_size > 0, seed := csum --> pushing data
1629 * from_size > 0, to_size == 0, seed := csum --> pulling data
1630 * from_size > 0, to_size > 0, seed := 0 --> diffing data
1631 *
1632 * Even for diffing, from_size and to_size don't need to be equal.
1633 */
1634 if (unlikely(((from_size | to_size) & (sizeof(__be32) - 1)) ||
1635 diff_size > sizeof(sp->diff)))
1636 return -EINVAL;
1637
1638 for (i = 0; i < from_size / sizeof(__be32); i++, j++)
1639 sp->diff[j] = ~from[i];
1640 for (i = 0; i < to_size / sizeof(__be32); i++, j++)
1641 sp->diff[j] = to[i];
1642
1643 return csum_partial(sp->diff, diff_size, seed);
1644 }
1645
1646 static const struct bpf_func_proto bpf_csum_diff_proto = {
1647 .func = bpf_csum_diff,
1648 .gpl_only = false,
1649 .pkt_access = true,
1650 .ret_type = RET_INTEGER,
1651 .arg1_type = ARG_PTR_TO_MEM_OR_NULL,
1652 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
1653 .arg3_type = ARG_PTR_TO_MEM_OR_NULL,
1654 .arg4_type = ARG_CONST_SIZE_OR_ZERO,
1655 .arg5_type = ARG_ANYTHING,
1656 };
1657
1658 BPF_CALL_2(bpf_csum_update, struct sk_buff *, skb, __wsum, csum)
1659 {
1660 /* The interface is to be used in combination with bpf_csum_diff()
1661 * for direct packet writes. csum rotation for alignment as well
1662 * as emulating csum_sub() can be done from the eBPF program.
1663 */
1664 if (skb->ip_summed == CHECKSUM_COMPLETE)
1665 return (skb->csum = csum_add(skb->csum, csum));
1666
1667 return -ENOTSUPP;
1668 }
1669
1670 static const struct bpf_func_proto bpf_csum_update_proto = {
1671 .func = bpf_csum_update,
1672 .gpl_only = false,
1673 .ret_type = RET_INTEGER,
1674 .arg1_type = ARG_PTR_TO_CTX,
1675 .arg2_type = ARG_ANYTHING,
1676 };
1677
1678 static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb)
1679 {
1680 return dev_forward_skb(dev, skb);
1681 }
1682
1683 static inline int __bpf_rx_skb_no_mac(struct net_device *dev,
1684 struct sk_buff *skb)
1685 {
1686 int ret = ____dev_forward_skb(dev, skb);
1687
1688 if (likely(!ret)) {
1689 skb->dev = dev;
1690 ret = netif_rx(skb);
1691 }
1692
1693 return ret;
1694 }
1695
1696 static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb)
1697 {
1698 int ret;
1699
1700 if (unlikely(__this_cpu_read(xmit_recursion) > XMIT_RECURSION_LIMIT)) {
1701 net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
1702 kfree_skb(skb);
1703 return -ENETDOWN;
1704 }
1705
1706 skb->dev = dev;
1707
1708 __this_cpu_inc(xmit_recursion);
1709 ret = dev_queue_xmit(skb);
1710 __this_cpu_dec(xmit_recursion);
1711
1712 return ret;
1713 }
1714
1715 static int __bpf_redirect_no_mac(struct sk_buff *skb, struct net_device *dev,
1716 u32 flags)
1717 {
1718 /* skb->mac_len is not set on normal egress */
1719 unsigned int mlen = skb->network_header - skb->mac_header;
1720
1721 __skb_pull(skb, mlen);
1722
1723 /* At ingress, the mac header has already been pulled once.
1724 * At egress, skb_pospull_rcsum has to be done in case that
1725 * the skb is originated from ingress (i.e. a forwarded skb)
1726 * to ensure that rcsum starts at net header.
1727 */
1728 if (!skb_at_tc_ingress(skb))
1729 skb_postpull_rcsum(skb, skb_mac_header(skb), mlen);
1730 skb_pop_mac_header(skb);
1731 skb_reset_mac_len(skb);
1732 return flags & BPF_F_INGRESS ?
1733 __bpf_rx_skb_no_mac(dev, skb) : __bpf_tx_skb(dev, skb);
1734 }
1735
1736 static int __bpf_redirect_common(struct sk_buff *skb, struct net_device *dev,
1737 u32 flags)
1738 {
1739 /* Verify that a link layer header is carried */
1740 if (unlikely(skb->mac_header >= skb->network_header)) {
1741 kfree_skb(skb);
1742 return -ERANGE;
1743 }
1744
1745 bpf_push_mac_rcsum(skb);
1746 return flags & BPF_F_INGRESS ?
1747 __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb);
1748 }
1749
1750 static int __bpf_redirect(struct sk_buff *skb, struct net_device *dev,
1751 u32 flags)
1752 {
1753 if (dev_is_mac_header_xmit(dev))
1754 return __bpf_redirect_common(skb, dev, flags);
1755 else
1756 return __bpf_redirect_no_mac(skb, dev, flags);
1757 }
1758
1759 BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags)
1760 {
1761 struct net_device *dev;
1762 struct sk_buff *clone;
1763 int ret;
1764
1765 if (unlikely(flags & ~(BPF_F_INGRESS)))
1766 return -EINVAL;
1767
1768 dev = dev_get_by_index_rcu(dev_net(skb->dev), ifindex);
1769 if (unlikely(!dev))
1770 return -EINVAL;
1771
1772 clone = skb_clone(skb, GFP_ATOMIC);
1773 if (unlikely(!clone))
1774 return -ENOMEM;
1775
1776 /* For direct write, we need to keep the invariant that the skbs
1777 * we're dealing with need to be uncloned. Should uncloning fail
1778 * here, we need to free the just generated clone to unclone once
1779 * again.
1780 */
1781 ret = bpf_try_make_head_writable(skb);
1782 if (unlikely(ret)) {
1783 kfree_skb(clone);
1784 return -ENOMEM;
1785 }
1786
1787 return __bpf_redirect(clone, dev, flags);
1788 }
1789
1790 static const struct bpf_func_proto bpf_clone_redirect_proto = {
1791 .func = bpf_clone_redirect,
1792 .gpl_only = false,
1793 .ret_type = RET_INTEGER,
1794 .arg1_type = ARG_PTR_TO_CTX,
1795 .arg2_type = ARG_ANYTHING,
1796 .arg3_type = ARG_ANYTHING,
1797 };
1798
1799 struct redirect_info {
1800 u32 ifindex;
1801 u32 flags;
1802 struct bpf_map *map;
1803 struct bpf_map *map_to_flush;
1804 unsigned long map_owner;
1805 };
1806
1807 static DEFINE_PER_CPU(struct redirect_info, redirect_info);
1808
1809 BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags)
1810 {
1811 struct redirect_info *ri = this_cpu_ptr(&redirect_info);
1812
1813 if (unlikely(flags & ~(BPF_F_INGRESS)))
1814 return TC_ACT_SHOT;
1815
1816 ri->ifindex = ifindex;
1817 ri->flags = flags;
1818
1819 return TC_ACT_REDIRECT;
1820 }
1821
1822 int skb_do_redirect(struct sk_buff *skb)
1823 {
1824 struct redirect_info *ri = this_cpu_ptr(&redirect_info);
1825 struct net_device *dev;
1826
1827 dev = dev_get_by_index_rcu(dev_net(skb->dev), ri->ifindex);
1828 ri->ifindex = 0;
1829 if (unlikely(!dev)) {
1830 kfree_skb(skb);
1831 return -EINVAL;
1832 }
1833
1834 return __bpf_redirect(skb, dev, ri->flags);
1835 }
1836
1837 static const struct bpf_func_proto bpf_redirect_proto = {
1838 .func = bpf_redirect,
1839 .gpl_only = false,
1840 .ret_type = RET_INTEGER,
1841 .arg1_type = ARG_ANYTHING,
1842 .arg2_type = ARG_ANYTHING,
1843 };
1844
1845 BPF_CALL_4(bpf_sk_redirect_map, struct sk_buff *, skb,
1846 struct bpf_map *, map, u32, key, u64, flags)
1847 {
1848 struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
1849
1850 /* If user passes invalid input drop the packet. */
1851 if (unlikely(flags))
1852 return SK_DROP;
1853
1854 tcb->bpf.key = key;
1855 tcb->bpf.flags = flags;
1856 tcb->bpf.map = map;
1857
1858 return SK_PASS;
1859 }
1860
1861 struct sock *do_sk_redirect_map(struct sk_buff *skb)
1862 {
1863 struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
1864 struct sock *sk = NULL;
1865
1866 if (tcb->bpf.map) {
1867 sk = __sock_map_lookup_elem(tcb->bpf.map, tcb->bpf.key);
1868
1869 tcb->bpf.key = 0;
1870 tcb->bpf.map = NULL;
1871 }
1872
1873 return sk;
1874 }
1875
1876 static const struct bpf_func_proto bpf_sk_redirect_map_proto = {
1877 .func = bpf_sk_redirect_map,
1878 .gpl_only = false,
1879 .ret_type = RET_INTEGER,
1880 .arg1_type = ARG_PTR_TO_CTX,
1881 .arg2_type = ARG_CONST_MAP_PTR,
1882 .arg3_type = ARG_ANYTHING,
1883 .arg4_type = ARG_ANYTHING,
1884 };
1885
1886 BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb)
1887 {
1888 return task_get_classid(skb);
1889 }
1890
1891 static const struct bpf_func_proto bpf_get_cgroup_classid_proto = {
1892 .func = bpf_get_cgroup_classid,
1893 .gpl_only = false,
1894 .ret_type = RET_INTEGER,
1895 .arg1_type = ARG_PTR_TO_CTX,
1896 };
1897
1898 BPF_CALL_1(bpf_get_route_realm, const struct sk_buff *, skb)
1899 {
1900 return dst_tclassid(skb);
1901 }
1902
1903 static const struct bpf_func_proto bpf_get_route_realm_proto = {
1904 .func = bpf_get_route_realm,
1905 .gpl_only = false,
1906 .ret_type = RET_INTEGER,
1907 .arg1_type = ARG_PTR_TO_CTX,
1908 };
1909
1910 BPF_CALL_1(bpf_get_hash_recalc, struct sk_buff *, skb)
1911 {
1912 /* If skb_clear_hash() was called due to mangling, we can
1913 * trigger SW recalculation here. Later access to hash
1914 * can then use the inline skb->hash via context directly
1915 * instead of calling this helper again.
1916 */
1917 return skb_get_hash(skb);
1918 }
1919
1920 static const struct bpf_func_proto bpf_get_hash_recalc_proto = {
1921 .func = bpf_get_hash_recalc,
1922 .gpl_only = false,
1923 .ret_type = RET_INTEGER,
1924 .arg1_type = ARG_PTR_TO_CTX,
1925 };
1926
1927 BPF_CALL_1(bpf_set_hash_invalid, struct sk_buff *, skb)
1928 {
1929 /* After all direct packet write, this can be used once for
1930 * triggering a lazy recalc on next skb_get_hash() invocation.
1931 */
1932 skb_clear_hash(skb);
1933 return 0;
1934 }
1935
1936 static const struct bpf_func_proto bpf_set_hash_invalid_proto = {
1937 .func = bpf_set_hash_invalid,
1938 .gpl_only = false,
1939 .ret_type = RET_INTEGER,
1940 .arg1_type = ARG_PTR_TO_CTX,
1941 };
1942
1943 BPF_CALL_2(bpf_set_hash, struct sk_buff *, skb, u32, hash)
1944 {
1945 /* Set user specified hash as L4(+), so that it gets returned
1946 * on skb_get_hash() call unless BPF prog later on triggers a
1947 * skb_clear_hash().
1948 */
1949 __skb_set_sw_hash(skb, hash, true);
1950 return 0;
1951 }
1952
1953 static const struct bpf_func_proto bpf_set_hash_proto = {
1954 .func = bpf_set_hash,
1955 .gpl_only = false,
1956 .ret_type = RET_INTEGER,
1957 .arg1_type = ARG_PTR_TO_CTX,
1958 .arg2_type = ARG_ANYTHING,
1959 };
1960
1961 BPF_CALL_3(bpf_skb_vlan_push, struct sk_buff *, skb, __be16, vlan_proto,
1962 u16, vlan_tci)
1963 {
1964 int ret;
1965
1966 if (unlikely(vlan_proto != htons(ETH_P_8021Q) &&
1967 vlan_proto != htons(ETH_P_8021AD)))
1968 vlan_proto = htons(ETH_P_8021Q);
1969
1970 bpf_push_mac_rcsum(skb);
1971 ret = skb_vlan_push(skb, vlan_proto, vlan_tci);
1972 bpf_pull_mac_rcsum(skb);
1973
1974 bpf_compute_data_pointers(skb);
1975 return ret;
1976 }
1977
1978 const struct bpf_func_proto bpf_skb_vlan_push_proto = {
1979 .func = bpf_skb_vlan_push,
1980 .gpl_only = false,
1981 .ret_type = RET_INTEGER,
1982 .arg1_type = ARG_PTR_TO_CTX,
1983 .arg2_type = ARG_ANYTHING,
1984 .arg3_type = ARG_ANYTHING,
1985 };
1986 EXPORT_SYMBOL_GPL(bpf_skb_vlan_push_proto);
1987
1988 BPF_CALL_1(bpf_skb_vlan_pop, struct sk_buff *, skb)
1989 {
1990 int ret;
1991
1992 bpf_push_mac_rcsum(skb);
1993 ret = skb_vlan_pop(skb);
1994 bpf_pull_mac_rcsum(skb);
1995
1996 bpf_compute_data_pointers(skb);
1997 return ret;
1998 }
1999
2000 const struct bpf_func_proto bpf_skb_vlan_pop_proto = {
2001 .func = bpf_skb_vlan_pop,
2002 .gpl_only = false,
2003 .ret_type = RET_INTEGER,
2004 .arg1_type = ARG_PTR_TO_CTX,
2005 };
2006 EXPORT_SYMBOL_GPL(bpf_skb_vlan_pop_proto);
2007
2008 static int bpf_skb_generic_push(struct sk_buff *skb, u32 off, u32 len)
2009 {
2010 /* Caller already did skb_cow() with len as headroom,
2011 * so no need to do it here.
2012 */
2013 skb_push(skb, len);
2014 memmove(skb->data, skb->data + len, off);
2015 memset(skb->data + off, 0, len);
2016
2017 /* No skb_postpush_rcsum(skb, skb->data + off, len)
2018 * needed here as it does not change the skb->csum
2019 * result for checksum complete when summing over
2020 * zeroed blocks.
2021 */
2022 return 0;
2023 }
2024
2025 static int bpf_skb_generic_pop(struct sk_buff *skb, u32 off, u32 len)
2026 {
2027 /* skb_ensure_writable() is not needed here, as we're
2028 * already working on an uncloned skb.
2029 */
2030 if (unlikely(!pskb_may_pull(skb, off + len)))
2031 return -ENOMEM;
2032
2033 skb_postpull_rcsum(skb, skb->data + off, len);
2034 memmove(skb->data + len, skb->data, off);
2035 __skb_pull(skb, len);
2036
2037 return 0;
2038 }
2039
2040 static int bpf_skb_net_hdr_push(struct sk_buff *skb, u32 off, u32 len)
2041 {
2042 bool trans_same = skb->transport_header == skb->network_header;
2043 int ret;
2044
2045 /* There's no need for __skb_push()/__skb_pull() pair to
2046 * get to the start of the mac header as we're guaranteed
2047 * to always start from here under eBPF.
2048 */
2049 ret = bpf_skb_generic_push(skb, off, len);
2050 if (likely(!ret)) {
2051 skb->mac_header -= len;
2052 skb->network_header -= len;
2053 if (trans_same)
2054 skb->transport_header = skb->network_header;
2055 }
2056
2057 return ret;
2058 }
2059
2060 static int bpf_skb_net_hdr_pop(struct sk_buff *skb, u32 off, u32 len)
2061 {
2062 bool trans_same = skb->transport_header == skb->network_header;
2063 int ret;
2064
2065 /* Same here, __skb_push()/__skb_pull() pair not needed. */
2066 ret = bpf_skb_generic_pop(skb, off, len);
2067 if (likely(!ret)) {
2068 skb->mac_header += len;
2069 skb->network_header += len;
2070 if (trans_same)
2071 skb->transport_header = skb->network_header;
2072 }
2073
2074 return ret;
2075 }
2076
2077 static int bpf_skb_proto_4_to_6(struct sk_buff *skb)
2078 {
2079 const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
2080 u32 off = skb_mac_header_len(skb);
2081 int ret;
2082
2083 ret = skb_cow(skb, len_diff);
2084 if (unlikely(ret < 0))
2085 return ret;
2086
2087 ret = bpf_skb_net_hdr_push(skb, off, len_diff);
2088 if (unlikely(ret < 0))
2089 return ret;
2090
2091 if (skb_is_gso(skb)) {
2092 /* SKB_GSO_TCPV4 needs to be changed into
2093 * SKB_GSO_TCPV6.
2094 */
2095 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) {
2096 skb_shinfo(skb)->gso_type &= ~SKB_GSO_TCPV4;
2097 skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV6;
2098 }
2099
2100 /* Due to IPv6 header, MSS needs to be downgraded. */
2101 skb_shinfo(skb)->gso_size -= len_diff;
2102 /* Header must be checked, and gso_segs recomputed. */
2103 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2104 skb_shinfo(skb)->gso_segs = 0;
2105 }
2106
2107 skb->protocol = htons(ETH_P_IPV6);
2108 skb_clear_hash(skb);
2109
2110 return 0;
2111 }
2112
2113 static int bpf_skb_proto_6_to_4(struct sk_buff *skb)
2114 {
2115 const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
2116 u32 off = skb_mac_header_len(skb);
2117 int ret;
2118
2119 ret = skb_unclone(skb, GFP_ATOMIC);
2120 if (unlikely(ret < 0))
2121 return ret;
2122
2123 ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
2124 if (unlikely(ret < 0))
2125 return ret;
2126
2127 if (skb_is_gso(skb)) {
2128 /* SKB_GSO_TCPV6 needs to be changed into
2129 * SKB_GSO_TCPV4.
2130 */
2131 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6) {
2132 skb_shinfo(skb)->gso_type &= ~SKB_GSO_TCPV6;
2133 skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV4;
2134 }
2135
2136 /* Due to IPv4 header, MSS can be upgraded. */
2137 skb_shinfo(skb)->gso_size += len_diff;
2138 /* Header must be checked, and gso_segs recomputed. */
2139 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2140 skb_shinfo(skb)->gso_segs = 0;
2141 }
2142
2143 skb->protocol = htons(ETH_P_IP);
2144 skb_clear_hash(skb);
2145
2146 return 0;
2147 }
2148
2149 static int bpf_skb_proto_xlat(struct sk_buff *skb, __be16 to_proto)
2150 {
2151 __be16 from_proto = skb->protocol;
2152
2153 if (from_proto == htons(ETH_P_IP) &&
2154 to_proto == htons(ETH_P_IPV6))
2155 return bpf_skb_proto_4_to_6(skb);
2156
2157 if (from_proto == htons(ETH_P_IPV6) &&
2158 to_proto == htons(ETH_P_IP))
2159 return bpf_skb_proto_6_to_4(skb);
2160
2161 return -ENOTSUPP;
2162 }
2163
2164 BPF_CALL_3(bpf_skb_change_proto, struct sk_buff *, skb, __be16, proto,
2165 u64, flags)
2166 {
2167 int ret;
2168
2169 if (unlikely(flags))
2170 return -EINVAL;
2171
2172 /* General idea is that this helper does the basic groundwork
2173 * needed for changing the protocol, and eBPF program fills the
2174 * rest through bpf_skb_store_bytes(), bpf_lX_csum_replace()
2175 * and other helpers, rather than passing a raw buffer here.
2176 *
2177 * The rationale is to keep this minimal and without a need to
2178 * deal with raw packet data. F.e. even if we would pass buffers
2179 * here, the program still needs to call the bpf_lX_csum_replace()
2180 * helpers anyway. Plus, this way we keep also separation of
2181 * concerns, since f.e. bpf_skb_store_bytes() should only take
2182 * care of stores.
2183 *
2184 * Currently, additional options and extension header space are
2185 * not supported, but flags register is reserved so we can adapt
2186 * that. For offloads, we mark packet as dodgy, so that headers
2187 * need to be verified first.
2188 */
2189 ret = bpf_skb_proto_xlat(skb, proto);
2190 bpf_compute_data_pointers(skb);
2191 return ret;
2192 }
2193
2194 static const struct bpf_func_proto bpf_skb_change_proto_proto = {
2195 .func = bpf_skb_change_proto,
2196 .gpl_only = false,
2197 .ret_type = RET_INTEGER,
2198 .arg1_type = ARG_PTR_TO_CTX,
2199 .arg2_type = ARG_ANYTHING,
2200 .arg3_type = ARG_ANYTHING,
2201 };
2202
2203 BPF_CALL_2(bpf_skb_change_type, struct sk_buff *, skb, u32, pkt_type)
2204 {
2205 /* We only allow a restricted subset to be changed for now. */
2206 if (unlikely(!skb_pkt_type_ok(skb->pkt_type) ||
2207 !skb_pkt_type_ok(pkt_type)))
2208 return -EINVAL;
2209
2210 skb->pkt_type = pkt_type;
2211 return 0;
2212 }
2213
2214 static const struct bpf_func_proto bpf_skb_change_type_proto = {
2215 .func = bpf_skb_change_type,
2216 .gpl_only = false,
2217 .ret_type = RET_INTEGER,
2218 .arg1_type = ARG_PTR_TO_CTX,
2219 .arg2_type = ARG_ANYTHING,
2220 };
2221
2222 static u32 bpf_skb_net_base_len(const struct sk_buff *skb)
2223 {
2224 switch (skb->protocol) {
2225 case htons(ETH_P_IP):
2226 return sizeof(struct iphdr);
2227 case htons(ETH_P_IPV6):
2228 return sizeof(struct ipv6hdr);
2229 default:
2230 return ~0U;
2231 }
2232 }
2233
2234 static int bpf_skb_net_grow(struct sk_buff *skb, u32 len_diff)
2235 {
2236 u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb);
2237 int ret;
2238
2239 ret = skb_cow(skb, len_diff);
2240 if (unlikely(ret < 0))
2241 return ret;
2242
2243 ret = bpf_skb_net_hdr_push(skb, off, len_diff);
2244 if (unlikely(ret < 0))
2245 return ret;
2246
2247 if (skb_is_gso(skb)) {
2248 /* Due to header grow, MSS needs to be downgraded. */
2249 skb_shinfo(skb)->gso_size -= len_diff;
2250 /* Header must be checked, and gso_segs recomputed. */
2251 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2252 skb_shinfo(skb)->gso_segs = 0;
2253 }
2254
2255 return 0;
2256 }
2257
2258 static int bpf_skb_net_shrink(struct sk_buff *skb, u32 len_diff)
2259 {
2260 u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb);
2261 int ret;
2262
2263 ret = skb_unclone(skb, GFP_ATOMIC);
2264 if (unlikely(ret < 0))
2265 return ret;
2266
2267 ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
2268 if (unlikely(ret < 0))
2269 return ret;
2270
2271 if (skb_is_gso(skb)) {
2272 /* Due to header shrink, MSS can be upgraded. */
2273 skb_shinfo(skb)->gso_size += len_diff;
2274 /* Header must be checked, and gso_segs recomputed. */
2275 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2276 skb_shinfo(skb)->gso_segs = 0;
2277 }
2278
2279 return 0;
2280 }
2281
2282 static u32 __bpf_skb_max_len(const struct sk_buff *skb)
2283 {
2284 return skb->dev->mtu + skb->dev->hard_header_len;
2285 }
2286
2287 static int bpf_skb_adjust_net(struct sk_buff *skb, s32 len_diff)
2288 {
2289 bool trans_same = skb->transport_header == skb->network_header;
2290 u32 len_cur, len_diff_abs = abs(len_diff);
2291 u32 len_min = bpf_skb_net_base_len(skb);
2292 u32 len_max = __bpf_skb_max_len(skb);
2293 __be16 proto = skb->protocol;
2294 bool shrink = len_diff < 0;
2295 int ret;
2296
2297 if (unlikely(len_diff_abs > 0xfffU))
2298 return -EFAULT;
2299 if (unlikely(proto != htons(ETH_P_IP) &&
2300 proto != htons(ETH_P_IPV6)))
2301 return -ENOTSUPP;
2302
2303 len_cur = skb->len - skb_network_offset(skb);
2304 if (skb_transport_header_was_set(skb) && !trans_same)
2305 len_cur = skb_network_header_len(skb);
2306 if ((shrink && (len_diff_abs >= len_cur ||
2307 len_cur - len_diff_abs < len_min)) ||
2308 (!shrink && (skb->len + len_diff_abs > len_max &&
2309 !skb_is_gso(skb))))
2310 return -ENOTSUPP;
2311
2312 ret = shrink ? bpf_skb_net_shrink(skb, len_diff_abs) :
2313 bpf_skb_net_grow(skb, len_diff_abs);
2314
2315 bpf_compute_data_pointers(skb);
2316 return ret;
2317 }
2318
2319 BPF_CALL_4(bpf_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
2320 u32, mode, u64, flags)
2321 {
2322 if (unlikely(flags))
2323 return -EINVAL;
2324 if (likely(mode == BPF_ADJ_ROOM_NET))
2325 return bpf_skb_adjust_net(skb, len_diff);
2326
2327 return -ENOTSUPP;
2328 }
2329
2330 static const struct bpf_func_proto bpf_skb_adjust_room_proto = {
2331 .func = bpf_skb_adjust_room,
2332 .gpl_only = false,
2333 .ret_type = RET_INTEGER,
2334 .arg1_type = ARG_PTR_TO_CTX,
2335 .arg2_type = ARG_ANYTHING,
2336 .arg3_type = ARG_ANYTHING,
2337 .arg4_type = ARG_ANYTHING,
2338 };
2339
2340 static u32 __bpf_skb_min_len(const struct sk_buff *skb)
2341 {
2342 u32 min_len = skb_network_offset(skb);
2343
2344 if (skb_transport_header_was_set(skb))
2345 min_len = skb_transport_offset(skb);
2346 if (skb->ip_summed == CHECKSUM_PARTIAL)
2347 min_len = skb_checksum_start_offset(skb) +
2348 skb->csum_offset + sizeof(__sum16);
2349 return min_len;
2350 }
2351
2352 static int bpf_skb_grow_rcsum(struct sk_buff *skb, unsigned int new_len)
2353 {
2354 unsigned int old_len = skb->len;
2355 int ret;
2356
2357 ret = __skb_grow_rcsum(skb, new_len);
2358 if (!ret)
2359 memset(skb->data + old_len, 0, new_len - old_len);
2360 return ret;
2361 }
2362
2363 static int bpf_skb_trim_rcsum(struct sk_buff *skb, unsigned int new_len)
2364 {
2365 return __skb_trim_rcsum(skb, new_len);
2366 }
2367
2368 BPF_CALL_3(bpf_skb_change_tail, struct sk_buff *, skb, u32, new_len,
2369 u64, flags)
2370 {
2371 u32 max_len = __bpf_skb_max_len(skb);
2372 u32 min_len = __bpf_skb_min_len(skb);
2373 int ret;
2374
2375 if (unlikely(flags || new_len > max_len || new_len < min_len))
2376 return -EINVAL;
2377 if (skb->encapsulation)
2378 return -ENOTSUPP;
2379
2380 /* The basic idea of this helper is that it's performing the
2381 * needed work to either grow or trim an skb, and eBPF program
2382 * rewrites the rest via helpers like bpf_skb_store_bytes(),
2383 * bpf_lX_csum_replace() and others rather than passing a raw
2384 * buffer here. This one is a slow path helper and intended
2385 * for replies with control messages.
2386 *
2387 * Like in bpf_skb_change_proto(), we want to keep this rather
2388 * minimal and without protocol specifics so that we are able
2389 * to separate concerns as in bpf_skb_store_bytes() should only
2390 * be the one responsible for writing buffers.
2391 *
2392 * It's really expected to be a slow path operation here for
2393 * control message replies, so we're implicitly linearizing,
2394 * uncloning and drop offloads from the skb by this.
2395 */
2396 ret = __bpf_try_make_writable(skb, skb->len);
2397 if (!ret) {
2398 if (new_len > skb->len)
2399 ret = bpf_skb_grow_rcsum(skb, new_len);
2400 else if (new_len < skb->len)
2401 ret = bpf_skb_trim_rcsum(skb, new_len);
2402 if (!ret && skb_is_gso(skb))
2403 skb_gso_reset(skb);
2404 }
2405
2406 bpf_compute_data_pointers(skb);
2407 return ret;
2408 }
2409
2410 static const struct bpf_func_proto bpf_skb_change_tail_proto = {
2411 .func = bpf_skb_change_tail,
2412 .gpl_only = false,
2413 .ret_type = RET_INTEGER,
2414 .arg1_type = ARG_PTR_TO_CTX,
2415 .arg2_type = ARG_ANYTHING,
2416 .arg3_type = ARG_ANYTHING,
2417 };
2418
2419 BPF_CALL_3(bpf_skb_change_head, struct sk_buff *, skb, u32, head_room,
2420 u64, flags)
2421 {
2422 u32 max_len = __bpf_skb_max_len(skb);
2423 u32 new_len = skb->len + head_room;
2424 int ret;
2425
2426 if (unlikely(flags || (!skb_is_gso(skb) && new_len > max_len) ||
2427 new_len < skb->len))
2428 return -EINVAL;
2429
2430 ret = skb_cow(skb, head_room);
2431 if (likely(!ret)) {
2432 /* Idea for this helper is that we currently only
2433 * allow to expand on mac header. This means that
2434 * skb->protocol network header, etc, stay as is.
2435 * Compared to bpf_skb_change_tail(), we're more
2436 * flexible due to not needing to linearize or
2437 * reset GSO. Intention for this helper is to be
2438 * used by an L3 skb that needs to push mac header
2439 * for redirection into L2 device.
2440 */
2441 __skb_push(skb, head_room);
2442 memset(skb->data, 0, head_room);
2443 skb_reset_mac_header(skb);
2444 }
2445
2446 bpf_compute_data_pointers(skb);
2447 return 0;
2448 }
2449
2450 static const struct bpf_func_proto bpf_skb_change_head_proto = {
2451 .func = bpf_skb_change_head,
2452 .gpl_only = false,
2453 .ret_type = RET_INTEGER,
2454 .arg1_type = ARG_PTR_TO_CTX,
2455 .arg2_type = ARG_ANYTHING,
2456 .arg3_type = ARG_ANYTHING,
2457 };
2458
2459 static unsigned long xdp_get_metalen(const struct xdp_buff *xdp)
2460 {
2461 return xdp_data_meta_unsupported(xdp) ? 0 :
2462 xdp->data - xdp->data_meta;
2463 }
2464
2465 BPF_CALL_2(bpf_xdp_adjust_head, struct xdp_buff *, xdp, int, offset)
2466 {
2467 unsigned long metalen = xdp_get_metalen(xdp);
2468 void *data_start = xdp->data_hard_start + metalen;
2469 void *data = xdp->data + offset;
2470
2471 if (unlikely(data < data_start ||
2472 data > xdp->data_end - ETH_HLEN))
2473 return -EINVAL;
2474
2475 if (metalen)
2476 memmove(xdp->data_meta + offset,
2477 xdp->data_meta, metalen);
2478 xdp->data_meta += offset;
2479 xdp->data = data;
2480
2481 return 0;
2482 }
2483
2484 static const struct bpf_func_proto bpf_xdp_adjust_head_proto = {
2485 .func = bpf_xdp_adjust_head,
2486 .gpl_only = false,
2487 .ret_type = RET_INTEGER,
2488 .arg1_type = ARG_PTR_TO_CTX,
2489 .arg2_type = ARG_ANYTHING,
2490 };
2491
2492 BPF_CALL_2(bpf_xdp_adjust_meta, struct xdp_buff *, xdp, int, offset)
2493 {
2494 void *meta = xdp->data_meta + offset;
2495 unsigned long metalen = xdp->data - meta;
2496
2497 if (xdp_data_meta_unsupported(xdp))
2498 return -ENOTSUPP;
2499 if (unlikely(meta < xdp->data_hard_start ||
2500 meta > xdp->data))
2501 return -EINVAL;
2502 if (unlikely((metalen & (sizeof(__u32) - 1)) ||
2503 (metalen > 32)))
2504 return -EACCES;
2505
2506 xdp->data_meta = meta;
2507
2508 return 0;
2509 }
2510
2511 static const struct bpf_func_proto bpf_xdp_adjust_meta_proto = {
2512 .func = bpf_xdp_adjust_meta,
2513 .gpl_only = false,
2514 .ret_type = RET_INTEGER,
2515 .arg1_type = ARG_PTR_TO_CTX,
2516 .arg2_type = ARG_ANYTHING,
2517 };
2518
2519 static int __bpf_tx_xdp(struct net_device *dev,
2520 struct bpf_map *map,
2521 struct xdp_buff *xdp,
2522 u32 index)
2523 {
2524 int err;
2525
2526 if (!dev->netdev_ops->ndo_xdp_xmit) {
2527 return -EOPNOTSUPP;
2528 }
2529
2530 err = dev->netdev_ops->ndo_xdp_xmit(dev, xdp);
2531 if (err)
2532 return err;
2533 dev->netdev_ops->ndo_xdp_flush(dev);
2534 return 0;
2535 }
2536
2537 static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd,
2538 struct bpf_map *map,
2539 struct xdp_buff *xdp,
2540 u32 index)
2541 {
2542 int err;
2543
2544 if (map->map_type == BPF_MAP_TYPE_DEVMAP) {
2545 struct net_device *dev = fwd;
2546
2547 if (!dev->netdev_ops->ndo_xdp_xmit)
2548 return -EOPNOTSUPP;
2549
2550 err = dev->netdev_ops->ndo_xdp_xmit(dev, xdp);
2551 if (err)
2552 return err;
2553 __dev_map_insert_ctx(map, index);
2554
2555 } else if (map->map_type == BPF_MAP_TYPE_CPUMAP) {
2556 struct bpf_cpu_map_entry *rcpu = fwd;
2557
2558 err = cpu_map_enqueue(rcpu, xdp, dev_rx);
2559 if (err)
2560 return err;
2561 __cpu_map_insert_ctx(map, index);
2562 }
2563 return 0;
2564 }
2565
2566 void xdp_do_flush_map(void)
2567 {
2568 struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2569 struct bpf_map *map = ri->map_to_flush;
2570
2571 ri->map_to_flush = NULL;
2572 if (map) {
2573 switch (map->map_type) {
2574 case BPF_MAP_TYPE_DEVMAP:
2575 __dev_map_flush(map);
2576 break;
2577 case BPF_MAP_TYPE_CPUMAP:
2578 __cpu_map_flush(map);
2579 break;
2580 default:
2581 break;
2582 }
2583 }
2584 }
2585 EXPORT_SYMBOL_GPL(xdp_do_flush_map);
2586
2587 static void *__xdp_map_lookup_elem(struct bpf_map *map, u32 index)
2588 {
2589 switch (map->map_type) {
2590 case BPF_MAP_TYPE_DEVMAP:
2591 return __dev_map_lookup_elem(map, index);
2592 case BPF_MAP_TYPE_CPUMAP:
2593 return __cpu_map_lookup_elem(map, index);
2594 default:
2595 return NULL;
2596 }
2597 }
2598
2599 static inline bool xdp_map_invalid(const struct bpf_prog *xdp_prog,
2600 unsigned long aux)
2601 {
2602 return (unsigned long)xdp_prog->aux != aux;
2603 }
2604
2605 static int xdp_do_redirect_map(struct net_device *dev, struct xdp_buff *xdp,
2606 struct bpf_prog *xdp_prog)
2607 {
2608 struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2609 unsigned long map_owner = ri->map_owner;
2610 struct bpf_map *map = ri->map;
2611 u32 index = ri->ifindex;
2612 void *fwd = NULL;
2613 int err;
2614
2615 ri->ifindex = 0;
2616 ri->map = NULL;
2617 ri->map_owner = 0;
2618
2619 if (unlikely(xdp_map_invalid(xdp_prog, map_owner))) {
2620 err = -EFAULT;
2621 map = NULL;
2622 goto err;
2623 }
2624
2625 fwd = __xdp_map_lookup_elem(map, index);
2626 if (!fwd) {
2627 err = -EINVAL;
2628 goto err;
2629 }
2630 if (ri->map_to_flush && ri->map_to_flush != map)
2631 xdp_do_flush_map();
2632
2633 err = __bpf_tx_xdp_map(dev, fwd, map, xdp, index);
2634 if (unlikely(err))
2635 goto err;
2636
2637 ri->map_to_flush = map;
2638 _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index);
2639 return 0;
2640 err:
2641 _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err);
2642 return err;
2643 }
2644
2645 int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp,
2646 struct bpf_prog *xdp_prog)
2647 {
2648 struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2649 struct net_device *fwd;
2650 u32 index = ri->ifindex;
2651 int err;
2652
2653 if (ri->map)
2654 return xdp_do_redirect_map(dev, xdp, xdp_prog);
2655
2656 fwd = dev_get_by_index_rcu(dev_net(dev), index);
2657 ri->ifindex = 0;
2658 if (unlikely(!fwd)) {
2659 err = -EINVAL;
2660 goto err;
2661 }
2662
2663 err = __bpf_tx_xdp(fwd, NULL, xdp, 0);
2664 if (unlikely(err))
2665 goto err;
2666
2667 _trace_xdp_redirect(dev, xdp_prog, index);
2668 return 0;
2669 err:
2670 _trace_xdp_redirect_err(dev, xdp_prog, index, err);
2671 return err;
2672 }
2673 EXPORT_SYMBOL_GPL(xdp_do_redirect);
2674
2675 static int __xdp_generic_ok_fwd_dev(struct sk_buff *skb, struct net_device *fwd)
2676 {
2677 unsigned int len;
2678
2679 if (unlikely(!(fwd->flags & IFF_UP)))
2680 return -ENETDOWN;
2681
2682 len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN;
2683 if (skb->len > len)
2684 return -EMSGSIZE;
2685
2686 return 0;
2687 }
2688
2689 int xdp_do_generic_redirect_map(struct net_device *dev, struct sk_buff *skb,
2690 struct bpf_prog *xdp_prog)
2691 {
2692 struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2693 unsigned long map_owner = ri->map_owner;
2694 struct bpf_map *map = ri->map;
2695 struct net_device *fwd = NULL;
2696 u32 index = ri->ifindex;
2697 int err = 0;
2698
2699 ri->ifindex = 0;
2700 ri->map = NULL;
2701 ri->map_owner = 0;
2702
2703 if (unlikely(xdp_map_invalid(xdp_prog, map_owner))) {
2704 err = -EFAULT;
2705 map = NULL;
2706 goto err;
2707 }
2708 fwd = __xdp_map_lookup_elem(map, index);
2709 if (unlikely(!fwd)) {
2710 err = -EINVAL;
2711 goto err;
2712 }
2713
2714 if (map->map_type == BPF_MAP_TYPE_DEVMAP) {
2715 if (unlikely((err = __xdp_generic_ok_fwd_dev(skb, fwd))))
2716 goto err;
2717 skb->dev = fwd;
2718 } else {
2719 /* TODO: Handle BPF_MAP_TYPE_CPUMAP */
2720 err = -EBADRQC;
2721 goto err;
2722 }
2723
2724 _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index);
2725 return 0;
2726 err:
2727 _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err);
2728 return err;
2729 }
2730
2731 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
2732 struct bpf_prog *xdp_prog)
2733 {
2734 struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2735 u32 index = ri->ifindex;
2736 struct net_device *fwd;
2737 int err = 0;
2738
2739 if (ri->map)
2740 return xdp_do_generic_redirect_map(dev, skb, xdp_prog);
2741
2742 ri->ifindex = 0;
2743 fwd = dev_get_by_index_rcu(dev_net(dev), index);
2744 if (unlikely(!fwd)) {
2745 err = -EINVAL;
2746 goto err;
2747 }
2748
2749 if (unlikely((err = __xdp_generic_ok_fwd_dev(skb, fwd))))
2750 goto err;
2751
2752 skb->dev = fwd;
2753 _trace_xdp_redirect(dev, xdp_prog, index);
2754 return 0;
2755 err:
2756 _trace_xdp_redirect_err(dev, xdp_prog, index, err);
2757 return err;
2758 }
2759 EXPORT_SYMBOL_GPL(xdp_do_generic_redirect);
2760
2761 BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags)
2762 {
2763 struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2764
2765 if (unlikely(flags))
2766 return XDP_ABORTED;
2767
2768 ri->ifindex = ifindex;
2769 ri->flags = flags;
2770 ri->map = NULL;
2771 ri->map_owner = 0;
2772
2773 return XDP_REDIRECT;
2774 }
2775
2776 static const struct bpf_func_proto bpf_xdp_redirect_proto = {
2777 .func = bpf_xdp_redirect,
2778 .gpl_only = false,
2779 .ret_type = RET_INTEGER,
2780 .arg1_type = ARG_ANYTHING,
2781 .arg2_type = ARG_ANYTHING,
2782 };
2783
2784 BPF_CALL_4(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex, u64, flags,
2785 unsigned long, map_owner)
2786 {
2787 struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2788
2789 if (unlikely(flags))
2790 return XDP_ABORTED;
2791
2792 ri->ifindex = ifindex;
2793 ri->flags = flags;
2794 ri->map = map;
2795 ri->map_owner = map_owner;
2796
2797 return XDP_REDIRECT;
2798 }
2799
2800 /* Note, arg4 is hidden from users and populated by the verifier
2801 * with the right pointer.
2802 */
2803 static const struct bpf_func_proto bpf_xdp_redirect_map_proto = {
2804 .func = bpf_xdp_redirect_map,
2805 .gpl_only = false,
2806 .ret_type = RET_INTEGER,
2807 .arg1_type = ARG_CONST_MAP_PTR,
2808 .arg2_type = ARG_ANYTHING,
2809 .arg3_type = ARG_ANYTHING,
2810 };
2811
2812 bool bpf_helper_changes_pkt_data(void *func)
2813 {
2814 if (func == bpf_skb_vlan_push ||
2815 func == bpf_skb_vlan_pop ||
2816 func == bpf_skb_store_bytes ||
2817 func == bpf_skb_change_proto ||
2818 func == bpf_skb_change_head ||
2819 func == bpf_skb_change_tail ||
2820 func == bpf_skb_adjust_room ||
2821 func == bpf_skb_pull_data ||
2822 func == bpf_clone_redirect ||
2823 func == bpf_l3_csum_replace ||
2824 func == bpf_l4_csum_replace ||
2825 func == bpf_xdp_adjust_head ||
2826 func == bpf_xdp_adjust_meta)
2827 return true;
2828
2829 return false;
2830 }
2831
2832 static unsigned long bpf_skb_copy(void *dst_buff, const void *skb,
2833 unsigned long off, unsigned long len)
2834 {
2835 void *ptr = skb_header_pointer(skb, off, len, dst_buff);
2836
2837 if (unlikely(!ptr))
2838 return len;
2839 if (ptr != dst_buff)
2840 memcpy(dst_buff, ptr, len);
2841
2842 return 0;
2843 }
2844
2845 BPF_CALL_5(bpf_skb_event_output, struct sk_buff *, skb, struct bpf_map *, map,
2846 u64, flags, void *, meta, u64, meta_size)
2847 {
2848 u64 skb_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
2849
2850 if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
2851 return -EINVAL;
2852 if (unlikely(skb_size > skb->len))
2853 return -EFAULT;
2854
2855 return bpf_event_output(map, flags, meta, meta_size, skb, skb_size,
2856 bpf_skb_copy);
2857 }
2858
2859 static const struct bpf_func_proto bpf_skb_event_output_proto = {
2860 .func = bpf_skb_event_output,
2861 .gpl_only = true,
2862 .ret_type = RET_INTEGER,
2863 .arg1_type = ARG_PTR_TO_CTX,
2864 .arg2_type = ARG_CONST_MAP_PTR,
2865 .arg3_type = ARG_ANYTHING,
2866 .arg4_type = ARG_PTR_TO_MEM,
2867 .arg5_type = ARG_CONST_SIZE,
2868 };
2869
2870 static unsigned short bpf_tunnel_key_af(u64 flags)
2871 {
2872 return flags & BPF_F_TUNINFO_IPV6 ? AF_INET6 : AF_INET;
2873 }
2874
2875 BPF_CALL_4(bpf_skb_get_tunnel_key, struct sk_buff *, skb, struct bpf_tunnel_key *, to,
2876 u32, size, u64, flags)
2877 {
2878 const struct ip_tunnel_info *info = skb_tunnel_info(skb);
2879 u8 compat[sizeof(struct bpf_tunnel_key)];
2880 void *to_orig = to;
2881 int err;
2882
2883 if (unlikely(!info || (flags & ~(BPF_F_TUNINFO_IPV6)))) {
2884 err = -EINVAL;
2885 goto err_clear;
2886 }
2887 if (ip_tunnel_info_af(info) != bpf_tunnel_key_af(flags)) {
2888 err = -EPROTO;
2889 goto err_clear;
2890 }
2891 if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
2892 err = -EINVAL;
2893 switch (size) {
2894 case offsetof(struct bpf_tunnel_key, tunnel_label):
2895 case offsetof(struct bpf_tunnel_key, tunnel_ext):
2896 goto set_compat;
2897 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
2898 /* Fixup deprecated structure layouts here, so we have
2899 * a common path later on.
2900 */
2901 if (ip_tunnel_info_af(info) != AF_INET)
2902 goto err_clear;
2903 set_compat:
2904 to = (struct bpf_tunnel_key *)compat;
2905 break;
2906 default:
2907 goto err_clear;
2908 }
2909 }
2910
2911 to->tunnel_id = be64_to_cpu(info->key.tun_id);
2912 to->tunnel_tos = info->key.tos;
2913 to->tunnel_ttl = info->key.ttl;
2914
2915 if (flags & BPF_F_TUNINFO_IPV6) {
2916 memcpy(to->remote_ipv6, &info->key.u.ipv6.src,
2917 sizeof(to->remote_ipv6));
2918 to->tunnel_label = be32_to_cpu(info->key.label);
2919 } else {
2920 to->remote_ipv4 = be32_to_cpu(info->key.u.ipv4.src);
2921 }
2922
2923 if (unlikely(size != sizeof(struct bpf_tunnel_key)))
2924 memcpy(to_orig, to, size);
2925
2926 return 0;
2927 err_clear:
2928 memset(to_orig, 0, size);
2929 return err;
2930 }
2931
2932 static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto = {
2933 .func = bpf_skb_get_tunnel_key,
2934 .gpl_only = false,
2935 .ret_type = RET_INTEGER,
2936 .arg1_type = ARG_PTR_TO_CTX,
2937 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
2938 .arg3_type = ARG_CONST_SIZE,
2939 .arg4_type = ARG_ANYTHING,
2940 };
2941
2942 BPF_CALL_3(bpf_skb_get_tunnel_opt, struct sk_buff *, skb, u8 *, to, u32, size)
2943 {
2944 const struct ip_tunnel_info *info = skb_tunnel_info(skb);
2945 int err;
2946
2947 if (unlikely(!info ||
2948 !(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT))) {
2949 err = -ENOENT;
2950 goto err_clear;
2951 }
2952 if (unlikely(size < info->options_len)) {
2953 err = -ENOMEM;
2954 goto err_clear;
2955 }
2956
2957 ip_tunnel_info_opts_get(to, info);
2958 if (size > info->options_len)
2959 memset(to + info->options_len, 0, size - info->options_len);
2960
2961 return info->options_len;
2962 err_clear:
2963 memset(to, 0, size);
2964 return err;
2965 }
2966
2967 static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto = {
2968 .func = bpf_skb_get_tunnel_opt,
2969 .gpl_only = false,
2970 .ret_type = RET_INTEGER,
2971 .arg1_type = ARG_PTR_TO_CTX,
2972 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
2973 .arg3_type = ARG_CONST_SIZE,
2974 };
2975
2976 static struct metadata_dst __percpu *md_dst;
2977
2978 BPF_CALL_4(bpf_skb_set_tunnel_key, struct sk_buff *, skb,
2979 const struct bpf_tunnel_key *, from, u32, size, u64, flags)
2980 {
2981 struct metadata_dst *md = this_cpu_ptr(md_dst);
2982 u8 compat[sizeof(struct bpf_tunnel_key)];
2983 struct ip_tunnel_info *info;
2984
2985 if (unlikely(flags & ~(BPF_F_TUNINFO_IPV6 | BPF_F_ZERO_CSUM_TX |
2986 BPF_F_DONT_FRAGMENT)))
2987 return -EINVAL;
2988 if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
2989 switch (size) {
2990 case offsetof(struct bpf_tunnel_key, tunnel_label):
2991 case offsetof(struct bpf_tunnel_key, tunnel_ext):
2992 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
2993 /* Fixup deprecated structure layouts here, so we have
2994 * a common path later on.
2995 */
2996 memcpy(compat, from, size);
2997 memset(compat + size, 0, sizeof(compat) - size);
2998 from = (const struct bpf_tunnel_key *) compat;
2999 break;
3000 default:
3001 return -EINVAL;
3002 }
3003 }
3004 if (unlikely((!(flags & BPF_F_TUNINFO_IPV6) && from->tunnel_label) ||
3005 from->tunnel_ext))
3006 return -EINVAL;
3007
3008 skb_dst_drop(skb);
3009 dst_hold((struct dst_entry *) md);
3010 skb_dst_set(skb, (struct dst_entry *) md);
3011
3012 info = &md->u.tun_info;
3013 info->mode = IP_TUNNEL_INFO_TX;
3014
3015 info->key.tun_flags = TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_NOCACHE;
3016 if (flags & BPF_F_DONT_FRAGMENT)
3017 info->key.tun_flags |= TUNNEL_DONT_FRAGMENT;
3018
3019 info->key.tun_id = cpu_to_be64(from->tunnel_id);
3020 info->key.tos = from->tunnel_tos;
3021 info->key.ttl = from->tunnel_ttl;
3022
3023 if (flags & BPF_F_TUNINFO_IPV6) {
3024 info->mode |= IP_TUNNEL_INFO_IPV6;
3025 memcpy(&info->key.u.ipv6.dst, from->remote_ipv6,
3026 sizeof(from->remote_ipv6));
3027 info->key.label = cpu_to_be32(from->tunnel_label) &
3028 IPV6_FLOWLABEL_MASK;
3029 } else {
3030 info->key.u.ipv4.dst = cpu_to_be32(from->remote_ipv4);
3031 if (flags & BPF_F_ZERO_CSUM_TX)
3032 info->key.tun_flags &= ~TUNNEL_CSUM;
3033 }
3034
3035 return 0;
3036 }
3037
3038 static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto = {
3039 .func = bpf_skb_set_tunnel_key,
3040 .gpl_only = false,
3041 .ret_type = RET_INTEGER,
3042 .arg1_type = ARG_PTR_TO_CTX,
3043 .arg2_type = ARG_PTR_TO_MEM,
3044 .arg3_type = ARG_CONST_SIZE,
3045 .arg4_type = ARG_ANYTHING,
3046 };
3047
3048 BPF_CALL_3(bpf_skb_set_tunnel_opt, struct sk_buff *, skb,
3049 const u8 *, from, u32, size)
3050 {
3051 struct ip_tunnel_info *info = skb_tunnel_info(skb);
3052 const struct metadata_dst *md = this_cpu_ptr(md_dst);
3053
3054 if (unlikely(info != &md->u.tun_info || (size & (sizeof(u32) - 1))))
3055 return -EINVAL;
3056 if (unlikely(size > IP_TUNNEL_OPTS_MAX))
3057 return -ENOMEM;
3058
3059 ip_tunnel_info_opts_set(info, from, size);
3060
3061 return 0;
3062 }
3063
3064 static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto = {
3065 .func = bpf_skb_set_tunnel_opt,
3066 .gpl_only = false,
3067 .ret_type = RET_INTEGER,
3068 .arg1_type = ARG_PTR_TO_CTX,
3069 .arg2_type = ARG_PTR_TO_MEM,
3070 .arg3_type = ARG_CONST_SIZE,
3071 };
3072
3073 static const struct bpf_func_proto *
3074 bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)
3075 {
3076 if (!md_dst) {
3077 struct metadata_dst __percpu *tmp;
3078
3079 tmp = metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX,
3080 METADATA_IP_TUNNEL,
3081 GFP_KERNEL);
3082 if (!tmp)
3083 return NULL;
3084 if (cmpxchg(&md_dst, NULL, tmp))
3085 metadata_dst_free_percpu(tmp);
3086 }
3087
3088 switch (which) {
3089 case BPF_FUNC_skb_set_tunnel_key:
3090 return &bpf_skb_set_tunnel_key_proto;
3091 case BPF_FUNC_skb_set_tunnel_opt:
3092 return &bpf_skb_set_tunnel_opt_proto;
3093 default:
3094 return NULL;
3095 }
3096 }
3097
3098 BPF_CALL_3(bpf_skb_under_cgroup, struct sk_buff *, skb, struct bpf_map *, map,
3099 u32, idx)
3100 {
3101 struct bpf_array *array = container_of(map, struct bpf_array, map);
3102 struct cgroup *cgrp;
3103 struct sock *sk;
3104
3105 sk = skb_to_full_sk(skb);
3106 if (!sk || !sk_fullsock(sk))
3107 return -ENOENT;
3108 if (unlikely(idx >= array->map.max_entries))
3109 return -E2BIG;
3110
3111 cgrp = READ_ONCE(array->ptrs[idx]);
3112 if (unlikely(!cgrp))
3113 return -EAGAIN;
3114
3115 return sk_under_cgroup_hierarchy(sk, cgrp);
3116 }
3117
3118 static const struct bpf_func_proto bpf_skb_under_cgroup_proto = {
3119 .func = bpf_skb_under_cgroup,
3120 .gpl_only = false,
3121 .ret_type = RET_INTEGER,
3122 .arg1_type = ARG_PTR_TO_CTX,
3123 .arg2_type = ARG_CONST_MAP_PTR,
3124 .arg3_type = ARG_ANYTHING,
3125 };
3126
3127 static unsigned long bpf_xdp_copy(void *dst_buff, const void *src_buff,
3128 unsigned long off, unsigned long len)
3129 {
3130 memcpy(dst_buff, src_buff + off, len);
3131 return 0;
3132 }
3133
3134 BPF_CALL_5(bpf_xdp_event_output, struct xdp_buff *, xdp, struct bpf_map *, map,
3135 u64, flags, void *, meta, u64, meta_size)
3136 {
3137 u64 xdp_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
3138
3139 if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
3140 return -EINVAL;
3141 if (unlikely(xdp_size > (unsigned long)(xdp->data_end - xdp->data)))
3142 return -EFAULT;
3143
3144 return bpf_event_output(map, flags, meta, meta_size, xdp->data,
3145 xdp_size, bpf_xdp_copy);
3146 }
3147
3148 static const struct bpf_func_proto bpf_xdp_event_output_proto = {
3149 .func = bpf_xdp_event_output,
3150 .gpl_only = true,
3151 .ret_type = RET_INTEGER,
3152 .arg1_type = ARG_PTR_TO_CTX,
3153 .arg2_type = ARG_CONST_MAP_PTR,
3154 .arg3_type = ARG_ANYTHING,
3155 .arg4_type = ARG_PTR_TO_MEM,
3156 .arg5_type = ARG_CONST_SIZE,
3157 };
3158
3159 BPF_CALL_1(bpf_get_socket_cookie, struct sk_buff *, skb)
3160 {
3161 return skb->sk ? sock_gen_cookie(skb->sk) : 0;
3162 }
3163
3164 static const struct bpf_func_proto bpf_get_socket_cookie_proto = {
3165 .func = bpf_get_socket_cookie,
3166 .gpl_only = false,
3167 .ret_type = RET_INTEGER,
3168 .arg1_type = ARG_PTR_TO_CTX,
3169 };
3170
3171 BPF_CALL_1(bpf_get_socket_uid, struct sk_buff *, skb)
3172 {
3173 struct sock *sk = sk_to_full_sk(skb->sk);
3174 kuid_t kuid;
3175
3176 if (!sk || !sk_fullsock(sk))
3177 return overflowuid;
3178 kuid = sock_net_uid(sock_net(sk), sk);
3179 return from_kuid_munged(sock_net(sk)->user_ns, kuid);
3180 }
3181
3182 static const struct bpf_func_proto bpf_get_socket_uid_proto = {
3183 .func = bpf_get_socket_uid,
3184 .gpl_only = false,
3185 .ret_type = RET_INTEGER,
3186 .arg1_type = ARG_PTR_TO_CTX,
3187 };
3188
3189 BPF_CALL_5(bpf_setsockopt, struct bpf_sock_ops_kern *, bpf_sock,
3190 int, level, int, optname, char *, optval, int, optlen)
3191 {
3192 struct sock *sk = bpf_sock->sk;
3193 int ret = 0;
3194 int val;
3195
3196 if (!sk_fullsock(sk))
3197 return -EINVAL;
3198
3199 if (level == SOL_SOCKET) {
3200 if (optlen != sizeof(int))
3201 return -EINVAL;
3202 val = *((int *)optval);
3203
3204 /* Only some socketops are supported */
3205 switch (optname) {
3206 case SO_RCVBUF:
3207 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
3208 sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
3209 break;
3210 case SO_SNDBUF:
3211 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
3212 sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF);
3213 break;
3214 case SO_MAX_PACING_RATE:
3215 sk->sk_max_pacing_rate = val;
3216 sk->sk_pacing_rate = min(sk->sk_pacing_rate,
3217 sk->sk_max_pacing_rate);
3218 break;
3219 case SO_PRIORITY:
3220 sk->sk_priority = val;
3221 break;
3222 case SO_RCVLOWAT:
3223 if (val < 0)
3224 val = INT_MAX;
3225 sk->sk_rcvlowat = val ? : 1;
3226 break;
3227 case SO_MARK:
3228 sk->sk_mark = val;
3229 break;
3230 default:
3231 ret = -EINVAL;
3232 }
3233 #ifdef CONFIG_INET
3234 } else if (level == SOL_TCP &&
3235 sk->sk_prot->setsockopt == tcp_setsockopt) {
3236 if (optname == TCP_CONGESTION) {
3237 char name[TCP_CA_NAME_MAX];
3238 bool reinit = bpf_sock->op > BPF_SOCK_OPS_NEEDS_ECN;
3239
3240 strncpy(name, optval, min_t(long, optlen,
3241 TCP_CA_NAME_MAX-1));
3242 name[TCP_CA_NAME_MAX-1] = 0;
3243 ret = tcp_set_congestion_control(sk, name, false, reinit);
3244 } else {
3245 struct tcp_sock *tp = tcp_sk(sk);
3246
3247 if (optlen != sizeof(int))
3248 return -EINVAL;
3249
3250 val = *((int *)optval);
3251 /* Only some options are supported */
3252 switch (optname) {
3253 case TCP_BPF_IW:
3254 if (val <= 0 || tp->data_segs_out > 0)
3255 ret = -EINVAL;
3256 else
3257 tp->snd_cwnd = val;
3258 break;
3259 case TCP_BPF_SNDCWND_CLAMP:
3260 if (val <= 0) {
3261 ret = -EINVAL;
3262 } else {
3263 tp->snd_cwnd_clamp = val;
3264 tp->snd_ssthresh = val;
3265 }
3266 break;
3267 default:
3268 ret = -EINVAL;
3269 }
3270 }
3271 #endif
3272 } else {
3273 ret = -EINVAL;
3274 }
3275 return ret;
3276 }
3277
3278 static const struct bpf_func_proto bpf_setsockopt_proto = {
3279 .func = bpf_setsockopt,
3280 .gpl_only = false,
3281 .ret_type = RET_INTEGER,
3282 .arg1_type = ARG_PTR_TO_CTX,
3283 .arg2_type = ARG_ANYTHING,
3284 .arg3_type = ARG_ANYTHING,
3285 .arg4_type = ARG_PTR_TO_MEM,
3286 .arg5_type = ARG_CONST_SIZE,
3287 };
3288
3289 BPF_CALL_5(bpf_getsockopt, struct bpf_sock_ops_kern *, bpf_sock,
3290 int, level, int, optname, char *, optval, int, optlen)
3291 {
3292 struct sock *sk = bpf_sock->sk;
3293
3294 if (!sk_fullsock(sk))
3295 goto err_clear;
3296
3297 #ifdef CONFIG_INET
3298 if (level == SOL_TCP && sk->sk_prot->getsockopt == tcp_getsockopt) {
3299 if (optname == TCP_CONGESTION) {
3300 struct inet_connection_sock *icsk = inet_csk(sk);
3301
3302 if (!icsk->icsk_ca_ops || optlen <= 1)
3303 goto err_clear;
3304 strncpy(optval, icsk->icsk_ca_ops->name, optlen);
3305 optval[optlen - 1] = 0;
3306 } else {
3307 goto err_clear;
3308 }
3309 } else {
3310 goto err_clear;
3311 }
3312 return 0;
3313 #endif
3314 err_clear:
3315 memset(optval, 0, optlen);
3316 return -EINVAL;
3317 }
3318
3319 static const struct bpf_func_proto bpf_getsockopt_proto = {
3320 .func = bpf_getsockopt,
3321 .gpl_only = false,
3322 .ret_type = RET_INTEGER,
3323 .arg1_type = ARG_PTR_TO_CTX,
3324 .arg2_type = ARG_ANYTHING,
3325 .arg3_type = ARG_ANYTHING,
3326 .arg4_type = ARG_PTR_TO_UNINIT_MEM,
3327 .arg5_type = ARG_CONST_SIZE,
3328 };
3329
3330 static const struct bpf_func_proto *
3331 bpf_base_func_proto(enum bpf_func_id func_id)
3332 {
3333 switch (func_id) {
3334 case BPF_FUNC_map_lookup_elem:
3335 return &bpf_map_lookup_elem_proto;
3336 case BPF_FUNC_map_update_elem:
3337 return &bpf_map_update_elem_proto;
3338 case BPF_FUNC_map_delete_elem:
3339 return &bpf_map_delete_elem_proto;
3340 case BPF_FUNC_get_prandom_u32:
3341 return &bpf_get_prandom_u32_proto;
3342 case BPF_FUNC_get_smp_processor_id:
3343 return &bpf_get_raw_smp_processor_id_proto;
3344 case BPF_FUNC_get_numa_node_id:
3345 return &bpf_get_numa_node_id_proto;
3346 case BPF_FUNC_tail_call:
3347 return &bpf_tail_call_proto;
3348 case BPF_FUNC_ktime_get_ns:
3349 return &bpf_ktime_get_ns_proto;
3350 case BPF_FUNC_trace_printk:
3351 if (capable(CAP_SYS_ADMIN))
3352 return bpf_get_trace_printk_proto();
3353 default:
3354 return NULL;
3355 }
3356 }
3357
3358 static const struct bpf_func_proto *
3359 sock_filter_func_proto(enum bpf_func_id func_id)
3360 {
3361 switch (func_id) {
3362 /* inet and inet6 sockets are created in a process
3363 * context so there is always a valid uid/gid
3364 */
3365 case BPF_FUNC_get_current_uid_gid:
3366 return &bpf_get_current_uid_gid_proto;
3367 default:
3368 return bpf_base_func_proto(func_id);
3369 }
3370 }
3371
3372 static const struct bpf_func_proto *
3373 sk_filter_func_proto(enum bpf_func_id func_id)
3374 {
3375 switch (func_id) {
3376 case BPF_FUNC_skb_load_bytes:
3377 return &bpf_skb_load_bytes_proto;
3378 case BPF_FUNC_get_socket_cookie:
3379 return &bpf_get_socket_cookie_proto;
3380 case BPF_FUNC_get_socket_uid:
3381 return &bpf_get_socket_uid_proto;
3382 default:
3383 return bpf_base_func_proto(func_id);
3384 }
3385 }
3386
3387 static const struct bpf_func_proto *
3388 tc_cls_act_func_proto(enum bpf_func_id func_id)
3389 {
3390 switch (func_id) {
3391 case BPF_FUNC_skb_store_bytes:
3392 return &bpf_skb_store_bytes_proto;
3393 case BPF_FUNC_skb_load_bytes:
3394 return &bpf_skb_load_bytes_proto;
3395 case BPF_FUNC_skb_pull_data:
3396 return &bpf_skb_pull_data_proto;
3397 case BPF_FUNC_csum_diff:
3398 return &bpf_csum_diff_proto;
3399 case BPF_FUNC_csum_update:
3400 return &bpf_csum_update_proto;
3401 case BPF_FUNC_l3_csum_replace:
3402 return &bpf_l3_csum_replace_proto;
3403 case BPF_FUNC_l4_csum_replace:
3404 return &bpf_l4_csum_replace_proto;
3405 case BPF_FUNC_clone_redirect:
3406 return &bpf_clone_redirect_proto;
3407 case BPF_FUNC_get_cgroup_classid:
3408 return &bpf_get_cgroup_classid_proto;
3409 case BPF_FUNC_skb_vlan_push:
3410 return &bpf_skb_vlan_push_proto;
3411 case BPF_FUNC_skb_vlan_pop:
3412 return &bpf_skb_vlan_pop_proto;
3413 case BPF_FUNC_skb_change_proto:
3414 return &bpf_skb_change_proto_proto;
3415 case BPF_FUNC_skb_change_type:
3416 return &bpf_skb_change_type_proto;
3417 case BPF_FUNC_skb_adjust_room:
3418 return &bpf_skb_adjust_room_proto;
3419 case BPF_FUNC_skb_change_tail:
3420 return &bpf_skb_change_tail_proto;
3421 case BPF_FUNC_skb_get_tunnel_key:
3422 return &bpf_skb_get_tunnel_key_proto;
3423 case BPF_FUNC_skb_set_tunnel_key:
3424 return bpf_get_skb_set_tunnel_proto(func_id);
3425 case BPF_FUNC_skb_get_tunnel_opt:
3426 return &bpf_skb_get_tunnel_opt_proto;
3427 case BPF_FUNC_skb_set_tunnel_opt:
3428 return bpf_get_skb_set_tunnel_proto(func_id);
3429 case BPF_FUNC_redirect:
3430 return &bpf_redirect_proto;
3431 case BPF_FUNC_get_route_realm:
3432 return &bpf_get_route_realm_proto;
3433 case BPF_FUNC_get_hash_recalc:
3434 return &bpf_get_hash_recalc_proto;
3435 case BPF_FUNC_set_hash_invalid:
3436 return &bpf_set_hash_invalid_proto;
3437 case BPF_FUNC_set_hash:
3438 return &bpf_set_hash_proto;
3439 case BPF_FUNC_perf_event_output:
3440 return &bpf_skb_event_output_proto;
3441 case BPF_FUNC_get_smp_processor_id:
3442 return &bpf_get_smp_processor_id_proto;
3443 case BPF_FUNC_skb_under_cgroup:
3444 return &bpf_skb_under_cgroup_proto;
3445 case BPF_FUNC_get_socket_cookie:
3446 return &bpf_get_socket_cookie_proto;
3447 case BPF_FUNC_get_socket_uid:
3448 return &bpf_get_socket_uid_proto;
3449 default:
3450 return bpf_base_func_proto(func_id);
3451 }
3452 }
3453
3454 static const struct bpf_func_proto *
3455 xdp_func_proto(enum bpf_func_id func_id)
3456 {
3457 switch (func_id) {
3458 case BPF_FUNC_perf_event_output:
3459 return &bpf_xdp_event_output_proto;
3460 case BPF_FUNC_get_smp_processor_id:
3461 return &bpf_get_smp_processor_id_proto;
3462 case BPF_FUNC_xdp_adjust_head:
3463 return &bpf_xdp_adjust_head_proto;
3464 case BPF_FUNC_xdp_adjust_meta:
3465 return &bpf_xdp_adjust_meta_proto;
3466 case BPF_FUNC_redirect:
3467 return &bpf_xdp_redirect_proto;
3468 case BPF_FUNC_redirect_map:
3469 return &bpf_xdp_redirect_map_proto;
3470 default:
3471 return bpf_base_func_proto(func_id);
3472 }
3473 }
3474
3475 static const struct bpf_func_proto *
3476 lwt_inout_func_proto(enum bpf_func_id func_id)
3477 {
3478 switch (func_id) {
3479 case BPF_FUNC_skb_load_bytes:
3480 return &bpf_skb_load_bytes_proto;
3481 case BPF_FUNC_skb_pull_data:
3482 return &bpf_skb_pull_data_proto;
3483 case BPF_FUNC_csum_diff:
3484 return &bpf_csum_diff_proto;
3485 case BPF_FUNC_get_cgroup_classid:
3486 return &bpf_get_cgroup_classid_proto;
3487 case BPF_FUNC_get_route_realm:
3488 return &bpf_get_route_realm_proto;
3489 case BPF_FUNC_get_hash_recalc:
3490 return &bpf_get_hash_recalc_proto;
3491 case BPF_FUNC_perf_event_output:
3492 return &bpf_skb_event_output_proto;
3493 case BPF_FUNC_get_smp_processor_id:
3494 return &bpf_get_smp_processor_id_proto;
3495 case BPF_FUNC_skb_under_cgroup:
3496 return &bpf_skb_under_cgroup_proto;
3497 default:
3498 return bpf_base_func_proto(func_id);
3499 }
3500 }
3501
3502 static const struct bpf_func_proto *
3503 sock_ops_func_proto(enum bpf_func_id func_id)
3504 {
3505 switch (func_id) {
3506 case BPF_FUNC_setsockopt:
3507 return &bpf_setsockopt_proto;
3508 case BPF_FUNC_getsockopt:
3509 return &bpf_getsockopt_proto;
3510 case BPF_FUNC_sock_map_update:
3511 return &bpf_sock_map_update_proto;
3512 default:
3513 return bpf_base_func_proto(func_id);
3514 }
3515 }
3516
3517 static const struct bpf_func_proto *sk_skb_func_proto(enum bpf_func_id func_id)
3518 {
3519 switch (func_id) {
3520 case BPF_FUNC_skb_store_bytes:
3521 return &bpf_skb_store_bytes_proto;
3522 case BPF_FUNC_skb_load_bytes:
3523 return &bpf_skb_load_bytes_proto;
3524 case BPF_FUNC_skb_pull_data:
3525 return &bpf_skb_pull_data_proto;
3526 case BPF_FUNC_skb_change_tail:
3527 return &bpf_skb_change_tail_proto;
3528 case BPF_FUNC_skb_change_head:
3529 return &bpf_skb_change_head_proto;
3530 case BPF_FUNC_get_socket_cookie:
3531 return &bpf_get_socket_cookie_proto;
3532 case BPF_FUNC_get_socket_uid:
3533 return &bpf_get_socket_uid_proto;
3534 case BPF_FUNC_sk_redirect_map:
3535 return &bpf_sk_redirect_map_proto;
3536 default:
3537 return bpf_base_func_proto(func_id);
3538 }
3539 }
3540
3541 static const struct bpf_func_proto *
3542 lwt_xmit_func_proto(enum bpf_func_id func_id)
3543 {
3544 switch (func_id) {
3545 case BPF_FUNC_skb_get_tunnel_key:
3546 return &bpf_skb_get_tunnel_key_proto;
3547 case BPF_FUNC_skb_set_tunnel_key:
3548 return bpf_get_skb_set_tunnel_proto(func_id);
3549 case BPF_FUNC_skb_get_tunnel_opt:
3550 return &bpf_skb_get_tunnel_opt_proto;
3551 case BPF_FUNC_skb_set_tunnel_opt:
3552 return bpf_get_skb_set_tunnel_proto(func_id);
3553 case BPF_FUNC_redirect:
3554 return &bpf_redirect_proto;
3555 case BPF_FUNC_clone_redirect:
3556 return &bpf_clone_redirect_proto;
3557 case BPF_FUNC_skb_change_tail:
3558 return &bpf_skb_change_tail_proto;
3559 case BPF_FUNC_skb_change_head:
3560 return &bpf_skb_change_head_proto;
3561 case BPF_FUNC_skb_store_bytes:
3562 return &bpf_skb_store_bytes_proto;
3563 case BPF_FUNC_csum_update:
3564 return &bpf_csum_update_proto;
3565 case BPF_FUNC_l3_csum_replace:
3566 return &bpf_l3_csum_replace_proto;
3567 case BPF_FUNC_l4_csum_replace:
3568 return &bpf_l4_csum_replace_proto;
3569 case BPF_FUNC_set_hash_invalid:
3570 return &bpf_set_hash_invalid_proto;
3571 default:
3572 return lwt_inout_func_proto(func_id);
3573 }
3574 }
3575
3576 static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type,
3577 struct bpf_insn_access_aux *info)
3578 {
3579 const int size_default = sizeof(__u32);
3580
3581 if (off < 0 || off >= sizeof(struct __sk_buff))
3582 return false;
3583
3584 /* The verifier guarantees that size > 0. */
3585 if (off % size != 0)
3586 return false;
3587
3588 switch (off) {
3589 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
3590 if (off + size > offsetofend(struct __sk_buff, cb[4]))
3591 return false;
3592 break;
3593 case bpf_ctx_range_till(struct __sk_buff, remote_ip6[0], remote_ip6[3]):
3594 case bpf_ctx_range_till(struct __sk_buff, local_ip6[0], local_ip6[3]):
3595 case bpf_ctx_range_till(struct __sk_buff, remote_ip4, remote_ip4):
3596 case bpf_ctx_range_till(struct __sk_buff, local_ip4, local_ip4):
3597 case bpf_ctx_range(struct __sk_buff, data):
3598 case bpf_ctx_range(struct __sk_buff, data_meta):
3599 case bpf_ctx_range(struct __sk_buff, data_end):
3600 if (size != size_default)
3601 return false;
3602 break;
3603 default:
3604 /* Only narrow read access allowed for now. */
3605 if (type == BPF_WRITE) {
3606 if (size != size_default)
3607 return false;
3608 } else {
3609 bpf_ctx_record_field_size(info, size_default);
3610 if (!bpf_ctx_narrow_access_ok(off, size, size_default))
3611 return false;
3612 }
3613 }
3614
3615 return true;
3616 }
3617
3618 static bool sk_filter_is_valid_access(int off, int size,
3619 enum bpf_access_type type,
3620 struct bpf_insn_access_aux *info)
3621 {
3622 switch (off) {
3623 case bpf_ctx_range(struct __sk_buff, tc_classid):
3624 case bpf_ctx_range(struct __sk_buff, data):
3625 case bpf_ctx_range(struct __sk_buff, data_meta):
3626 case bpf_ctx_range(struct __sk_buff, data_end):
3627 case bpf_ctx_range_till(struct __sk_buff, family, local_port):
3628 return false;
3629 }
3630
3631 if (type == BPF_WRITE) {
3632 switch (off) {
3633 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
3634 break;
3635 default:
3636 return false;
3637 }
3638 }
3639
3640 return bpf_skb_is_valid_access(off, size, type, info);
3641 }
3642
3643 static bool lwt_is_valid_access(int off, int size,
3644 enum bpf_access_type type,
3645 struct bpf_insn_access_aux *info)
3646 {
3647 switch (off) {
3648 case bpf_ctx_range(struct __sk_buff, tc_classid):
3649 case bpf_ctx_range_till(struct __sk_buff, family, local_port):
3650 case bpf_ctx_range(struct __sk_buff, data_meta):
3651 return false;
3652 }
3653
3654 if (type == BPF_WRITE) {
3655 switch (off) {
3656 case bpf_ctx_range(struct __sk_buff, mark):
3657 case bpf_ctx_range(struct __sk_buff, priority):
3658 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
3659 break;
3660 default:
3661 return false;
3662 }
3663 }
3664
3665 switch (off) {
3666 case bpf_ctx_range(struct __sk_buff, data):
3667 info->reg_type = PTR_TO_PACKET;
3668 break;
3669 case bpf_ctx_range(struct __sk_buff, data_end):
3670 info->reg_type = PTR_TO_PACKET_END;
3671 break;
3672 }
3673
3674 return bpf_skb_is_valid_access(off, size, type, info);
3675 }
3676
3677 static bool sock_filter_is_valid_access(int off, int size,
3678 enum bpf_access_type type,
3679 struct bpf_insn_access_aux *info)
3680 {
3681 if (type == BPF_WRITE) {
3682 switch (off) {
3683 case offsetof(struct bpf_sock, bound_dev_if):
3684 case offsetof(struct bpf_sock, mark):
3685 case offsetof(struct bpf_sock, priority):
3686 break;
3687 default:
3688 return false;
3689 }
3690 }
3691
3692 if (off < 0 || off + size > sizeof(struct bpf_sock))
3693 return false;
3694 /* The verifier guarantees that size > 0. */
3695 if (off % size != 0)
3696 return false;
3697 if (size != sizeof(__u32))
3698 return false;
3699
3700 return true;
3701 }
3702
3703 static int bpf_unclone_prologue(struct bpf_insn *insn_buf, bool direct_write,
3704 const struct bpf_prog *prog, int drop_verdict)
3705 {
3706 struct bpf_insn *insn = insn_buf;
3707
3708 if (!direct_write)
3709 return 0;
3710
3711 /* if (!skb->cloned)
3712 * goto start;
3713 *
3714 * (Fast-path, otherwise approximation that we might be
3715 * a clone, do the rest in helper.)
3716 */
3717 *insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_6, BPF_REG_1, CLONED_OFFSET());
3718 *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_6, CLONED_MASK);
3719 *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 7);
3720
3721 /* ret = bpf_skb_pull_data(skb, 0); */
3722 *insn++ = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
3723 *insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_2, BPF_REG_2);
3724 *insn++ = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
3725 BPF_FUNC_skb_pull_data);
3726 /* if (!ret)
3727 * goto restore;
3728 * return TC_ACT_SHOT;
3729 */
3730 *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2);
3731 *insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, drop_verdict);
3732 *insn++ = BPF_EXIT_INSN();
3733
3734 /* restore: */
3735 *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6);
3736 /* start: */
3737 *insn++ = prog->insnsi[0];
3738
3739 return insn - insn_buf;
3740 }
3741
3742 static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write,
3743 const struct bpf_prog *prog)
3744 {
3745 return bpf_unclone_prologue(insn_buf, direct_write, prog, TC_ACT_SHOT);
3746 }
3747
3748 static bool tc_cls_act_is_valid_access(int off, int size,
3749 enum bpf_access_type type,
3750 struct bpf_insn_access_aux *info)
3751 {
3752 if (type == BPF_WRITE) {
3753 switch (off) {
3754 case bpf_ctx_range(struct __sk_buff, mark):
3755 case bpf_ctx_range(struct __sk_buff, tc_index):
3756 case bpf_ctx_range(struct __sk_buff, priority):
3757 case bpf_ctx_range(struct __sk_buff, tc_classid):
3758 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
3759 break;
3760 default:
3761 return false;
3762 }
3763 }
3764
3765 switch (off) {
3766 case bpf_ctx_range(struct __sk_buff, data):
3767 info->reg_type = PTR_TO_PACKET;
3768 break;
3769 case bpf_ctx_range(struct __sk_buff, data_meta):
3770 info->reg_type = PTR_TO_PACKET_META;
3771 break;
3772 case bpf_ctx_range(struct __sk_buff, data_end):
3773 info->reg_type = PTR_TO_PACKET_END;
3774 break;
3775 case bpf_ctx_range_till(struct __sk_buff, family, local_port):
3776 return false;
3777 }
3778
3779 return bpf_skb_is_valid_access(off, size, type, info);
3780 }
3781
3782 static bool __is_valid_xdp_access(int off, int size)
3783 {
3784 if (off < 0 || off >= sizeof(struct xdp_md))
3785 return false;
3786 if (off % size != 0)
3787 return false;
3788 if (size != sizeof(__u32))
3789 return false;
3790
3791 return true;
3792 }
3793
3794 static bool xdp_is_valid_access(int off, int size,
3795 enum bpf_access_type type,
3796 struct bpf_insn_access_aux *info)
3797 {
3798 if (type == BPF_WRITE)
3799 return false;
3800
3801 switch (off) {
3802 case offsetof(struct xdp_md, data):
3803 info->reg_type = PTR_TO_PACKET;
3804 break;
3805 case offsetof(struct xdp_md, data_meta):
3806 info->reg_type = PTR_TO_PACKET_META;
3807 break;
3808 case offsetof(struct xdp_md, data_end):
3809 info->reg_type = PTR_TO_PACKET_END;
3810 break;
3811 }
3812
3813 return __is_valid_xdp_access(off, size);
3814 }
3815
3816 void bpf_warn_invalid_xdp_action(u32 act)
3817 {
3818 const u32 act_max = XDP_REDIRECT;
3819
3820 WARN_ONCE(1, "%s XDP return value %u, expect packet loss!\n",
3821 act > act_max ? "Illegal" : "Driver unsupported",
3822 act);
3823 }
3824 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);
3825
3826 static bool __is_valid_sock_ops_access(int off, int size)
3827 {
3828 if (off < 0 || off >= sizeof(struct bpf_sock_ops))
3829 return false;
3830 /* The verifier guarantees that size > 0. */
3831 if (off % size != 0)
3832 return false;
3833 if (size != sizeof(__u32))
3834 return false;
3835
3836 return true;
3837 }
3838
3839 static bool sock_ops_is_valid_access(int off, int size,
3840 enum bpf_access_type type,
3841 struct bpf_insn_access_aux *info)
3842 {
3843 if (type == BPF_WRITE) {
3844 switch (off) {
3845 case offsetof(struct bpf_sock_ops, op) ...
3846 offsetof(struct bpf_sock_ops, replylong[3]):
3847 break;
3848 default:
3849 return false;
3850 }
3851 }
3852
3853 return __is_valid_sock_ops_access(off, size);
3854 }
3855
3856 static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write,
3857 const struct bpf_prog *prog)
3858 {
3859 return bpf_unclone_prologue(insn_buf, direct_write, prog, SK_DROP);
3860 }
3861
3862 static bool sk_skb_is_valid_access(int off, int size,
3863 enum bpf_access_type type,
3864 struct bpf_insn_access_aux *info)
3865 {
3866 switch (off) {
3867 case bpf_ctx_range(struct __sk_buff, tc_classid):
3868 case bpf_ctx_range(struct __sk_buff, data_meta):
3869 return false;
3870 }
3871
3872 if (type == BPF_WRITE) {
3873 switch (off) {
3874 case bpf_ctx_range(struct __sk_buff, tc_index):
3875 case bpf_ctx_range(struct __sk_buff, priority):
3876 break;
3877 default:
3878 return false;
3879 }
3880 }
3881
3882 switch (off) {
3883 case bpf_ctx_range(struct __sk_buff, mark):
3884 return false;
3885 case bpf_ctx_range(struct __sk_buff, data):
3886 info->reg_type = PTR_TO_PACKET;
3887 break;
3888 case bpf_ctx_range(struct __sk_buff, data_end):
3889 info->reg_type = PTR_TO_PACKET_END;
3890 break;
3891 }
3892
3893 return bpf_skb_is_valid_access(off, size, type, info);
3894 }
3895
3896 static u32 bpf_convert_ctx_access(enum bpf_access_type type,
3897 const struct bpf_insn *si,
3898 struct bpf_insn *insn_buf,
3899 struct bpf_prog *prog, u32 *target_size)
3900 {
3901 struct bpf_insn *insn = insn_buf;
3902 int off;
3903
3904 switch (si->off) {
3905 case offsetof(struct __sk_buff, len):
3906 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
3907 bpf_target_off(struct sk_buff, len, 4,
3908 target_size));
3909 break;
3910
3911 case offsetof(struct __sk_buff, protocol):
3912 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
3913 bpf_target_off(struct sk_buff, protocol, 2,
3914 target_size));
3915 break;
3916
3917 case offsetof(struct __sk_buff, vlan_proto):
3918 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
3919 bpf_target_off(struct sk_buff, vlan_proto, 2,
3920 target_size));
3921 break;
3922
3923 case offsetof(struct __sk_buff, priority):
3924 if (type == BPF_WRITE)
3925 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
3926 bpf_target_off(struct sk_buff, priority, 4,
3927 target_size));
3928 else
3929 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
3930 bpf_target_off(struct sk_buff, priority, 4,
3931 target_size));
3932 break;
3933
3934 case offsetof(struct __sk_buff, ingress_ifindex):
3935 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
3936 bpf_target_off(struct sk_buff, skb_iif, 4,
3937 target_size));
3938 break;
3939
3940 case offsetof(struct __sk_buff, ifindex):
3941 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
3942 si->dst_reg, si->src_reg,
3943 offsetof(struct sk_buff, dev));
3944 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
3945 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
3946 bpf_target_off(struct net_device, ifindex, 4,
3947 target_size));
3948 break;
3949
3950 case offsetof(struct __sk_buff, hash):
3951 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
3952 bpf_target_off(struct sk_buff, hash, 4,
3953 target_size));
3954 break;
3955
3956 case offsetof(struct __sk_buff, mark):
3957 if (type == BPF_WRITE)
3958 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
3959 bpf_target_off(struct sk_buff, mark, 4,
3960 target_size));
3961 else
3962 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
3963 bpf_target_off(struct sk_buff, mark, 4,
3964 target_size));
3965 break;
3966
3967 case offsetof(struct __sk_buff, pkt_type):
3968 *target_size = 1;
3969 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
3970 PKT_TYPE_OFFSET());
3971 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, PKT_TYPE_MAX);
3972 #ifdef __BIG_ENDIAN_BITFIELD
3973 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 5);
3974 #endif
3975 break;
3976
3977 case offsetof(struct __sk_buff, queue_mapping):
3978 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
3979 bpf_target_off(struct sk_buff, queue_mapping, 2,
3980 target_size));
3981 break;
3982
3983 case offsetof(struct __sk_buff, vlan_present):
3984 case offsetof(struct __sk_buff, vlan_tci):
3985 BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
3986
3987 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
3988 bpf_target_off(struct sk_buff, vlan_tci, 2,
3989 target_size));
3990 if (si->off == offsetof(struct __sk_buff, vlan_tci)) {
3991 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg,
3992 ~VLAN_TAG_PRESENT);
3993 } else {
3994 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 12);
3995 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 1);
3996 }
3997 break;
3998
3999 case offsetof(struct __sk_buff, cb[0]) ...
4000 offsetofend(struct __sk_buff, cb[4]) - 1:
4001 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, data) < 20);
4002 BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
4003 offsetof(struct qdisc_skb_cb, data)) %
4004 sizeof(__u64));
4005
4006 prog->cb_access = 1;
4007 off = si->off;
4008 off -= offsetof(struct __sk_buff, cb[0]);
4009 off += offsetof(struct sk_buff, cb);
4010 off += offsetof(struct qdisc_skb_cb, data);
4011 if (type == BPF_WRITE)
4012 *insn++ = BPF_STX_MEM(BPF_SIZE(si->code), si->dst_reg,
4013 si->src_reg, off);
4014 else
4015 *insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
4016 si->src_reg, off);
4017 break;
4018
4019 case offsetof(struct __sk_buff, tc_classid):
4020 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, tc_classid) != 2);
4021
4022 off = si->off;
4023 off -= offsetof(struct __sk_buff, tc_classid);
4024 off += offsetof(struct sk_buff, cb);
4025 off += offsetof(struct qdisc_skb_cb, tc_classid);
4026 *target_size = 2;
4027 if (type == BPF_WRITE)
4028 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg,
4029 si->src_reg, off);
4030 else
4031 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg,
4032 si->src_reg, off);
4033 break;
4034
4035 case offsetof(struct __sk_buff, data):
4036 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
4037 si->dst_reg, si->src_reg,
4038 offsetof(struct sk_buff, data));
4039 break;
4040
4041 case offsetof(struct __sk_buff, data_meta):
4042 off = si->off;
4043 off -= offsetof(struct __sk_buff, data_meta);
4044 off += offsetof(struct sk_buff, cb);
4045 off += offsetof(struct bpf_skb_data_end, data_meta);
4046 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
4047 si->src_reg, off);
4048 break;
4049
4050 case offsetof(struct __sk_buff, data_end):
4051 off = si->off;
4052 off -= offsetof(struct __sk_buff, data_end);
4053 off += offsetof(struct sk_buff, cb);
4054 off += offsetof(struct bpf_skb_data_end, data_end);
4055 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
4056 si->src_reg, off);
4057 break;
4058
4059 case offsetof(struct __sk_buff, tc_index):
4060 #ifdef CONFIG_NET_SCHED
4061 if (type == BPF_WRITE)
4062 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, si->src_reg,
4063 bpf_target_off(struct sk_buff, tc_index, 2,
4064 target_size));
4065 else
4066 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
4067 bpf_target_off(struct sk_buff, tc_index, 2,
4068 target_size));
4069 #else
4070 *target_size = 2;
4071 if (type == BPF_WRITE)
4072 *insn++ = BPF_MOV64_REG(si->dst_reg, si->dst_reg);
4073 else
4074 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
4075 #endif
4076 break;
4077
4078 case offsetof(struct __sk_buff, napi_id):
4079 #if defined(CONFIG_NET_RX_BUSY_POLL)
4080 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4081 bpf_target_off(struct sk_buff, napi_id, 4,
4082 target_size));
4083 *insn++ = BPF_JMP_IMM(BPF_JGE, si->dst_reg, MIN_NAPI_ID, 1);
4084 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
4085 #else
4086 *target_size = 4;
4087 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
4088 #endif
4089 break;
4090 case offsetof(struct __sk_buff, family):
4091 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2);
4092
4093 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4094 si->dst_reg, si->src_reg,
4095 offsetof(struct sk_buff, sk));
4096 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
4097 bpf_target_off(struct sock_common,
4098 skc_family,
4099 2, target_size));
4100 break;
4101 case offsetof(struct __sk_buff, remote_ip4):
4102 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4);
4103
4104 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4105 si->dst_reg, si->src_reg,
4106 offsetof(struct sk_buff, sk));
4107 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4108 bpf_target_off(struct sock_common,
4109 skc_daddr,
4110 4, target_size));
4111 break;
4112 case offsetof(struct __sk_buff, local_ip4):
4113 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
4114 skc_rcv_saddr) != 4);
4115
4116 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4117 si->dst_reg, si->src_reg,
4118 offsetof(struct sk_buff, sk));
4119 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4120 bpf_target_off(struct sock_common,
4121 skc_rcv_saddr,
4122 4, target_size));
4123 break;
4124 case offsetof(struct __sk_buff, remote_ip6[0]) ...
4125 offsetof(struct __sk_buff, remote_ip6[3]):
4126 #if IS_ENABLED(CONFIG_IPV6)
4127 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
4128 skc_v6_daddr.s6_addr32[0]) != 4);
4129
4130 off = si->off;
4131 off -= offsetof(struct __sk_buff, remote_ip6[0]);
4132
4133 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4134 si->dst_reg, si->src_reg,
4135 offsetof(struct sk_buff, sk));
4136 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4137 offsetof(struct sock_common,
4138 skc_v6_daddr.s6_addr32[0]) +
4139 off);
4140 #else
4141 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
4142 #endif
4143 break;
4144 case offsetof(struct __sk_buff, local_ip6[0]) ...
4145 offsetof(struct __sk_buff, local_ip6[3]):
4146 #if IS_ENABLED(CONFIG_IPV6)
4147 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
4148 skc_v6_rcv_saddr.s6_addr32[0]) != 4);
4149
4150 off = si->off;
4151 off -= offsetof(struct __sk_buff, local_ip6[0]);
4152
4153 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4154 si->dst_reg, si->src_reg,
4155 offsetof(struct sk_buff, sk));
4156 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4157 offsetof(struct sock_common,
4158 skc_v6_rcv_saddr.s6_addr32[0]) +
4159 off);
4160 #else
4161 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
4162 #endif
4163 break;
4164
4165 case offsetof(struct __sk_buff, remote_port):
4166 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2);
4167
4168 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4169 si->dst_reg, si->src_reg,
4170 offsetof(struct sk_buff, sk));
4171 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
4172 bpf_target_off(struct sock_common,
4173 skc_dport,
4174 2, target_size));
4175 #ifndef __BIG_ENDIAN_BITFIELD
4176 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
4177 #endif
4178 break;
4179
4180 case offsetof(struct __sk_buff, local_port):
4181 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2);
4182
4183 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4184 si->dst_reg, si->src_reg,
4185 offsetof(struct sk_buff, sk));
4186 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
4187 bpf_target_off(struct sock_common,
4188 skc_num, 2, target_size));
4189 break;
4190 }
4191
4192 return insn - insn_buf;
4193 }
4194
4195 static u32 sock_filter_convert_ctx_access(enum bpf_access_type type,
4196 const struct bpf_insn *si,
4197 struct bpf_insn *insn_buf,
4198 struct bpf_prog *prog, u32 *target_size)
4199 {
4200 struct bpf_insn *insn = insn_buf;
4201
4202 switch (si->off) {
4203 case offsetof(struct bpf_sock, bound_dev_if):
4204 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_bound_dev_if) != 4);
4205
4206 if (type == BPF_WRITE)
4207 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
4208 offsetof(struct sock, sk_bound_dev_if));
4209 else
4210 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4211 offsetof(struct sock, sk_bound_dev_if));
4212 break;
4213
4214 case offsetof(struct bpf_sock, mark):
4215 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_mark) != 4);
4216
4217 if (type == BPF_WRITE)
4218 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
4219 offsetof(struct sock, sk_mark));
4220 else
4221 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4222 offsetof(struct sock, sk_mark));
4223 break;
4224
4225 case offsetof(struct bpf_sock, priority):
4226 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_priority) != 4);
4227
4228 if (type == BPF_WRITE)
4229 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
4230 offsetof(struct sock, sk_priority));
4231 else
4232 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4233 offsetof(struct sock, sk_priority));
4234 break;
4235
4236 case offsetof(struct bpf_sock, family):
4237 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_family) != 2);
4238
4239 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
4240 offsetof(struct sock, sk_family));
4241 break;
4242
4243 case offsetof(struct bpf_sock, type):
4244 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4245 offsetof(struct sock, __sk_flags_offset));
4246 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_TYPE_MASK);
4247 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_TYPE_SHIFT);
4248 break;
4249
4250 case offsetof(struct bpf_sock, protocol):
4251 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4252 offsetof(struct sock, __sk_flags_offset));
4253 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK);
4254 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_PROTO_SHIFT);
4255 break;
4256 }
4257
4258 return insn - insn_buf;
4259 }
4260
4261 static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type,
4262 const struct bpf_insn *si,
4263 struct bpf_insn *insn_buf,
4264 struct bpf_prog *prog, u32 *target_size)
4265 {
4266 struct bpf_insn *insn = insn_buf;
4267
4268 switch (si->off) {
4269 case offsetof(struct __sk_buff, ifindex):
4270 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
4271 si->dst_reg, si->src_reg,
4272 offsetof(struct sk_buff, dev));
4273 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4274 bpf_target_off(struct net_device, ifindex, 4,
4275 target_size));
4276 break;
4277 default:
4278 return bpf_convert_ctx_access(type, si, insn_buf, prog,
4279 target_size);
4280 }
4281
4282 return insn - insn_buf;
4283 }
4284
4285 static u32 xdp_convert_ctx_access(enum bpf_access_type type,
4286 const struct bpf_insn *si,
4287 struct bpf_insn *insn_buf,
4288 struct bpf_prog *prog, u32 *target_size)
4289 {
4290 struct bpf_insn *insn = insn_buf;
4291
4292 switch (si->off) {
4293 case offsetof(struct xdp_md, data):
4294 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data),
4295 si->dst_reg, si->src_reg,
4296 offsetof(struct xdp_buff, data));
4297 break;
4298 case offsetof(struct xdp_md, data_meta):
4299 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_meta),
4300 si->dst_reg, si->src_reg,
4301 offsetof(struct xdp_buff, data_meta));
4302 break;
4303 case offsetof(struct xdp_md, data_end):
4304 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_end),
4305 si->dst_reg, si->src_reg,
4306 offsetof(struct xdp_buff, data_end));
4307 break;
4308 }
4309
4310 return insn - insn_buf;
4311 }
4312
4313 static u32 sock_ops_convert_ctx_access(enum bpf_access_type type,
4314 const struct bpf_insn *si,
4315 struct bpf_insn *insn_buf,
4316 struct bpf_prog *prog,
4317 u32 *target_size)
4318 {
4319 struct bpf_insn *insn = insn_buf;
4320 int off;
4321
4322 switch (si->off) {
4323 case offsetof(struct bpf_sock_ops, op) ...
4324 offsetof(struct bpf_sock_ops, replylong[3]):
4325 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, op) !=
4326 FIELD_SIZEOF(struct bpf_sock_ops_kern, op));
4327 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, reply) !=
4328 FIELD_SIZEOF(struct bpf_sock_ops_kern, reply));
4329 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, replylong) !=
4330 FIELD_SIZEOF(struct bpf_sock_ops_kern, replylong));
4331 off = si->off;
4332 off -= offsetof(struct bpf_sock_ops, op);
4333 off += offsetof(struct bpf_sock_ops_kern, op);
4334 if (type == BPF_WRITE)
4335 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
4336 off);
4337 else
4338 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4339 off);
4340 break;
4341
4342 case offsetof(struct bpf_sock_ops, family):
4343 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2);
4344
4345 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4346 struct bpf_sock_ops_kern, sk),
4347 si->dst_reg, si->src_reg,
4348 offsetof(struct bpf_sock_ops_kern, sk));
4349 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
4350 offsetof(struct sock_common, skc_family));
4351 break;
4352
4353 case offsetof(struct bpf_sock_ops, remote_ip4):
4354 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4);
4355
4356 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4357 struct bpf_sock_ops_kern, sk),
4358 si->dst_reg, si->src_reg,
4359 offsetof(struct bpf_sock_ops_kern, sk));
4360 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4361 offsetof(struct sock_common, skc_daddr));
4362 break;
4363
4364 case offsetof(struct bpf_sock_ops, local_ip4):
4365 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_rcv_saddr) != 4);
4366
4367 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4368 struct bpf_sock_ops_kern, sk),
4369 si->dst_reg, si->src_reg,
4370 offsetof(struct bpf_sock_ops_kern, sk));
4371 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4372 offsetof(struct sock_common,
4373 skc_rcv_saddr));
4374 break;
4375
4376 case offsetof(struct bpf_sock_ops, remote_ip6[0]) ...
4377 offsetof(struct bpf_sock_ops, remote_ip6[3]):
4378 #if IS_ENABLED(CONFIG_IPV6)
4379 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
4380 skc_v6_daddr.s6_addr32[0]) != 4);
4381
4382 off = si->off;
4383 off -= offsetof(struct bpf_sock_ops, remote_ip6[0]);
4384 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4385 struct bpf_sock_ops_kern, sk),
4386 si->dst_reg, si->src_reg,
4387 offsetof(struct bpf_sock_ops_kern, sk));
4388 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4389 offsetof(struct sock_common,
4390 skc_v6_daddr.s6_addr32[0]) +
4391 off);
4392 #else
4393 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
4394 #endif
4395 break;
4396
4397 case offsetof(struct bpf_sock_ops, local_ip6[0]) ...
4398 offsetof(struct bpf_sock_ops, local_ip6[3]):
4399 #if IS_ENABLED(CONFIG_IPV6)
4400 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
4401 skc_v6_rcv_saddr.s6_addr32[0]) != 4);
4402
4403 off = si->off;
4404 off -= offsetof(struct bpf_sock_ops, local_ip6[0]);
4405 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4406 struct bpf_sock_ops_kern, sk),
4407 si->dst_reg, si->src_reg,
4408 offsetof(struct bpf_sock_ops_kern, sk));
4409 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4410 offsetof(struct sock_common,
4411 skc_v6_rcv_saddr.s6_addr32[0]) +
4412 off);
4413 #else
4414 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
4415 #endif
4416 break;
4417
4418 case offsetof(struct bpf_sock_ops, remote_port):
4419 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2);
4420
4421 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4422 struct bpf_sock_ops_kern, sk),
4423 si->dst_reg, si->src_reg,
4424 offsetof(struct bpf_sock_ops_kern, sk));
4425 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
4426 offsetof(struct sock_common, skc_dport));
4427 #ifndef __BIG_ENDIAN_BITFIELD
4428 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
4429 #endif
4430 break;
4431
4432 case offsetof(struct bpf_sock_ops, local_port):
4433 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2);
4434
4435 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4436 struct bpf_sock_ops_kern, sk),
4437 si->dst_reg, si->src_reg,
4438 offsetof(struct bpf_sock_ops_kern, sk));
4439 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
4440 offsetof(struct sock_common, skc_num));
4441 break;
4442 }
4443 return insn - insn_buf;
4444 }
4445
4446 static u32 sk_skb_convert_ctx_access(enum bpf_access_type type,
4447 const struct bpf_insn *si,
4448 struct bpf_insn *insn_buf,
4449 struct bpf_prog *prog, u32 *target_size)
4450 {
4451 struct bpf_insn *insn = insn_buf;
4452 int off;
4453
4454 switch (si->off) {
4455 case offsetof(struct __sk_buff, data_end):
4456 off = si->off;
4457 off -= offsetof(struct __sk_buff, data_end);
4458 off += offsetof(struct sk_buff, cb);
4459 off += offsetof(struct tcp_skb_cb, bpf.data_end);
4460 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
4461 si->src_reg, off);
4462 break;
4463 default:
4464 return bpf_convert_ctx_access(type, si, insn_buf, prog,
4465 target_size);
4466 }
4467
4468 return insn - insn_buf;
4469 }
4470
4471 const struct bpf_verifier_ops sk_filter_verifier_ops = {
4472 .get_func_proto = sk_filter_func_proto,
4473 .is_valid_access = sk_filter_is_valid_access,
4474 .convert_ctx_access = bpf_convert_ctx_access,
4475 };
4476
4477 const struct bpf_prog_ops sk_filter_prog_ops = {
4478 };
4479
4480 const struct bpf_verifier_ops tc_cls_act_verifier_ops = {
4481 .get_func_proto = tc_cls_act_func_proto,
4482 .is_valid_access = tc_cls_act_is_valid_access,
4483 .convert_ctx_access = tc_cls_act_convert_ctx_access,
4484 .gen_prologue = tc_cls_act_prologue,
4485 };
4486
4487 const struct bpf_prog_ops tc_cls_act_prog_ops = {
4488 .test_run = bpf_prog_test_run_skb,
4489 };
4490
4491 const struct bpf_verifier_ops xdp_verifier_ops = {
4492 .get_func_proto = xdp_func_proto,
4493 .is_valid_access = xdp_is_valid_access,
4494 .convert_ctx_access = xdp_convert_ctx_access,
4495 };
4496
4497 const struct bpf_prog_ops xdp_prog_ops = {
4498 .test_run = bpf_prog_test_run_xdp,
4499 };
4500
4501 const struct bpf_verifier_ops cg_skb_verifier_ops = {
4502 .get_func_proto = sk_filter_func_proto,
4503 .is_valid_access = sk_filter_is_valid_access,
4504 .convert_ctx_access = bpf_convert_ctx_access,
4505 };
4506
4507 const struct bpf_prog_ops cg_skb_prog_ops = {
4508 .test_run = bpf_prog_test_run_skb,
4509 };
4510
4511 const struct bpf_verifier_ops lwt_inout_verifier_ops = {
4512 .get_func_proto = lwt_inout_func_proto,
4513 .is_valid_access = lwt_is_valid_access,
4514 .convert_ctx_access = bpf_convert_ctx_access,
4515 };
4516
4517 const struct bpf_prog_ops lwt_inout_prog_ops = {
4518 .test_run = bpf_prog_test_run_skb,
4519 };
4520
4521 const struct bpf_verifier_ops lwt_xmit_verifier_ops = {
4522 .get_func_proto = lwt_xmit_func_proto,
4523 .is_valid_access = lwt_is_valid_access,
4524 .convert_ctx_access = bpf_convert_ctx_access,
4525 .gen_prologue = tc_cls_act_prologue,
4526 };
4527
4528 const struct bpf_prog_ops lwt_xmit_prog_ops = {
4529 .test_run = bpf_prog_test_run_skb,
4530 };
4531
4532 const struct bpf_verifier_ops cg_sock_verifier_ops = {
4533 .get_func_proto = sock_filter_func_proto,
4534 .is_valid_access = sock_filter_is_valid_access,
4535 .convert_ctx_access = sock_filter_convert_ctx_access,
4536 };
4537
4538 const struct bpf_prog_ops cg_sock_prog_ops = {
4539 };
4540
4541 const struct bpf_verifier_ops sock_ops_verifier_ops = {
4542 .get_func_proto = sock_ops_func_proto,
4543 .is_valid_access = sock_ops_is_valid_access,
4544 .convert_ctx_access = sock_ops_convert_ctx_access,
4545 };
4546
4547 const struct bpf_prog_ops sock_ops_prog_ops = {
4548 };
4549
4550 const struct bpf_verifier_ops sk_skb_verifier_ops = {
4551 .get_func_proto = sk_skb_func_proto,
4552 .is_valid_access = sk_skb_is_valid_access,
4553 .convert_ctx_access = sk_skb_convert_ctx_access,
4554 .gen_prologue = sk_skb_prologue,
4555 };
4556
4557 const struct bpf_prog_ops sk_skb_prog_ops = {
4558 };
4559
4560 int sk_detach_filter(struct sock *sk)
4561 {
4562 int ret = -ENOENT;
4563 struct sk_filter *filter;
4564
4565 if (sock_flag(sk, SOCK_FILTER_LOCKED))
4566 return -EPERM;
4567
4568 filter = rcu_dereference_protected(sk->sk_filter,
4569 lockdep_sock_is_held(sk));
4570 if (filter) {
4571 RCU_INIT_POINTER(sk->sk_filter, NULL);
4572 sk_filter_uncharge(sk, filter);
4573 ret = 0;
4574 }
4575
4576 return ret;
4577 }
4578 EXPORT_SYMBOL_GPL(sk_detach_filter);
4579
4580 int sk_get_filter(struct sock *sk, struct sock_filter __user *ubuf,
4581 unsigned int len)
4582 {
4583 struct sock_fprog_kern *fprog;
4584 struct sk_filter *filter;
4585 int ret = 0;
4586
4587 lock_sock(sk);
4588 filter = rcu_dereference_protected(sk->sk_filter,
4589 lockdep_sock_is_held(sk));
4590 if (!filter)
4591 goto out;
4592
4593 /* We're copying the filter that has been originally attached,
4594 * so no conversion/decode needed anymore. eBPF programs that
4595 * have no original program cannot be dumped through this.
4596 */
4597 ret = -EACCES;
4598 fprog = filter->prog->orig_prog;
4599 if (!fprog)
4600 goto out;
4601
4602 ret = fprog->len;
4603 if (!len)
4604 /* User space only enquires number of filter blocks. */
4605 goto out;
4606
4607 ret = -EINVAL;
4608 if (len < fprog->len)
4609 goto out;
4610
4611 ret = -EFAULT;
4612 if (copy_to_user(ubuf, fprog->filter, bpf_classic_proglen(fprog)))
4613 goto out;
4614
4615 /* Instead of bytes, the API requests to return the number
4616 * of filter blocks.
4617 */
4618 ret = fprog->len;
4619 out:
4620 release_sock(sk);
4621 return ret;
4622 }
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