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1// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2// Copyright (C) 2018 Facebook
3
4#ifndef _GNU_SOURCE
5#define _GNU_SOURCE
6#endif
7#include <errno.h>
8#include <fcntl.h>
9#include <stdlib.h>
10#include <string.h>
11#include <time.h>
12#include <unistd.h>
13#include <bpf/bpf.h>
14#include <bpf/libbpf.h>
15#include <net/if.h>
16#include <linux/rtnetlink.h>
17#include <linux/socket.h>
18#include <linux/tc_act/tc_bpf.h>
19#include <sys/socket.h>
20#include <sys/stat.h>
21#include <sys/types.h>
22
23#include "bpf/nlattr.h"
24#include "main.h"
25#include "netlink_dumper.h"
26
27#ifndef SOL_NETLINK
28#define SOL_NETLINK 270
29#endif
30
31struct ip_devname_ifindex {
32 char devname[64];
33 int ifindex;
34};
35
36struct bpf_netdev_t {
37 struct ip_devname_ifindex *devices;
38 int used_len;
39 int array_len;
40 int filter_idx;
41};
42
43struct tc_kind_handle {
44 char kind[64];
45 int handle;
46};
47
48struct bpf_tcinfo_t {
49 struct tc_kind_handle *handle_array;
50 int used_len;
51 int array_len;
52 bool is_qdisc;
53};
54
55struct bpf_filter_t {
56 const char *kind;
57 const char *devname;
58 int ifindex;
59};
60
61struct bpf_attach_info {
62 __u32 flow_dissector_id;
63};
64
65enum net_attach_type {
66 NET_ATTACH_TYPE_XDP,
67 NET_ATTACH_TYPE_XDP_GENERIC,
68 NET_ATTACH_TYPE_XDP_DRIVER,
69 NET_ATTACH_TYPE_XDP_OFFLOAD,
70 NET_ATTACH_TYPE_TCX_INGRESS,
71 NET_ATTACH_TYPE_TCX_EGRESS,
72};
73
74static const char * const attach_type_strings[] = {
75 [NET_ATTACH_TYPE_XDP] = "xdp",
76 [NET_ATTACH_TYPE_XDP_GENERIC] = "xdpgeneric",
77 [NET_ATTACH_TYPE_XDP_DRIVER] = "xdpdrv",
78 [NET_ATTACH_TYPE_XDP_OFFLOAD] = "xdpoffload",
79 [NET_ATTACH_TYPE_TCX_INGRESS] = "tcx_ingress",
80 [NET_ATTACH_TYPE_TCX_EGRESS] = "tcx_egress",
81};
82
83static const char * const attach_loc_strings[] = {
84 [BPF_TCX_INGRESS] = "tcx/ingress",
85 [BPF_TCX_EGRESS] = "tcx/egress",
86 [BPF_NETKIT_PRIMARY] = "netkit/primary",
87 [BPF_NETKIT_PEER] = "netkit/peer",
88};
89
90const size_t net_attach_type_size = ARRAY_SIZE(attach_type_strings);
91
92static enum net_attach_type parse_attach_type(const char *str)
93{
94 enum net_attach_type type;
95
96 for (type = 0; type < net_attach_type_size; type++) {
97 if (attach_type_strings[type] &&
98 is_prefix(str, attach_type_strings[type]))
99 return type;
100 }
101
102 return net_attach_type_size;
103}
104
105typedef int (*dump_nlmsg_t)(void *cookie, void *msg, struct nlattr **tb);
106
107typedef int (*__dump_nlmsg_t)(struct nlmsghdr *nlmsg, dump_nlmsg_t, void *cookie);
108
109static int netlink_open(__u32 *nl_pid)
110{
111 struct sockaddr_nl sa;
112 socklen_t addrlen;
113 int one = 1, ret;
114 int sock;
115
116 memset(&sa, 0, sizeof(sa));
117 sa.nl_family = AF_NETLINK;
118
119 sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
120 if (sock < 0)
121 return -errno;
122
123 if (setsockopt(sock, SOL_NETLINK, NETLINK_EXT_ACK,
124 &one, sizeof(one)) < 0) {
125 p_err("Netlink error reporting not supported");
126 }
127
128 if (bind(sock, (struct sockaddr *)&sa, sizeof(sa)) < 0) {
129 ret = -errno;
130 goto cleanup;
131 }
132
133 addrlen = sizeof(sa);
134 if (getsockname(sock, (struct sockaddr *)&sa, &addrlen) < 0) {
135 ret = -errno;
136 goto cleanup;
137 }
138
139 if (addrlen != sizeof(sa)) {
140 ret = -LIBBPF_ERRNO__INTERNAL;
141 goto cleanup;
142 }
143
144 *nl_pid = sa.nl_pid;
145 return sock;
146
147cleanup:
148 close(sock);
149 return ret;
150}
151
152static int netlink_recv(int sock, __u32 nl_pid, __u32 seq,
153 __dump_nlmsg_t _fn, dump_nlmsg_t fn,
154 void *cookie)
155{
156 bool multipart = true;
157 struct nlmsgerr *err;
158 struct nlmsghdr *nh;
159 char buf[8192];
160 int len, ret;
161
162 while (multipart) {
163 multipart = false;
164 len = recv(sock, buf, sizeof(buf), 0);
165 if (len < 0) {
166 ret = -errno;
167 goto done;
168 }
169
170 if (len == 0)
171 break;
172
173 for (nh = (struct nlmsghdr *)buf; NLMSG_OK(nh, (unsigned int)len);
174 nh = NLMSG_NEXT(nh, len)) {
175 if (nh->nlmsg_pid != nl_pid) {
176 ret = -LIBBPF_ERRNO__WRNGPID;
177 goto done;
178 }
179 if (nh->nlmsg_seq != seq) {
180 ret = -LIBBPF_ERRNO__INVSEQ;
181 goto done;
182 }
183 if (nh->nlmsg_flags & NLM_F_MULTI)
184 multipart = true;
185 switch (nh->nlmsg_type) {
186 case NLMSG_ERROR:
187 err = (struct nlmsgerr *)NLMSG_DATA(nh);
188 if (!err->error)
189 continue;
190 ret = err->error;
191 libbpf_nla_dump_errormsg(nh);
192 goto done;
193 case NLMSG_DONE:
194 return 0;
195 default:
196 break;
197 }
198 if (_fn) {
199 ret = _fn(nh, fn, cookie);
200 if (ret)
201 return ret;
202 }
203 }
204
205 if (len)
206 p_err("Invalid message or trailing data in Netlink response: %d bytes left", len);
207 }
208 ret = 0;
209done:
210 return ret;
211}
212
213static int __dump_class_nlmsg(struct nlmsghdr *nlh,
214 dump_nlmsg_t dump_class_nlmsg,
215 void *cookie)
216{
217 struct nlattr *tb[TCA_MAX + 1], *attr;
218 struct tcmsg *t = NLMSG_DATA(nlh);
219 int len;
220
221 len = nlh->nlmsg_len - NLMSG_LENGTH(sizeof(*t));
222 attr = (struct nlattr *) ((void *) t + NLMSG_ALIGN(sizeof(*t)));
223 if (libbpf_nla_parse(tb, TCA_MAX, attr, len, NULL) != 0)
224 return -LIBBPF_ERRNO__NLPARSE;
225
226 return dump_class_nlmsg(cookie, t, tb);
227}
228
229static int netlink_get_class(int sock, unsigned int nl_pid, int ifindex,
230 dump_nlmsg_t dump_class_nlmsg, void *cookie)
231{
232 struct {
233 struct nlmsghdr nlh;
234 struct tcmsg t;
235 } req = {
236 .nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg)),
237 .nlh.nlmsg_type = RTM_GETTCLASS,
238 .nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
239 .t.tcm_family = AF_UNSPEC,
240 .t.tcm_ifindex = ifindex,
241 };
242 int seq = time(NULL);
243
244 req.nlh.nlmsg_seq = seq;
245 if (send(sock, &req, req.nlh.nlmsg_len, 0) < 0)
246 return -errno;
247
248 return netlink_recv(sock, nl_pid, seq, __dump_class_nlmsg,
249 dump_class_nlmsg, cookie);
250}
251
252static int __dump_qdisc_nlmsg(struct nlmsghdr *nlh,
253 dump_nlmsg_t dump_qdisc_nlmsg,
254 void *cookie)
255{
256 struct nlattr *tb[TCA_MAX + 1], *attr;
257 struct tcmsg *t = NLMSG_DATA(nlh);
258 int len;
259
260 len = nlh->nlmsg_len - NLMSG_LENGTH(sizeof(*t));
261 attr = (struct nlattr *) ((void *) t + NLMSG_ALIGN(sizeof(*t)));
262 if (libbpf_nla_parse(tb, TCA_MAX, attr, len, NULL) != 0)
263 return -LIBBPF_ERRNO__NLPARSE;
264
265 return dump_qdisc_nlmsg(cookie, t, tb);
266}
267
268static int netlink_get_qdisc(int sock, unsigned int nl_pid, int ifindex,
269 dump_nlmsg_t dump_qdisc_nlmsg, void *cookie)
270{
271 struct {
272 struct nlmsghdr nlh;
273 struct tcmsg t;
274 } req = {
275 .nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg)),
276 .nlh.nlmsg_type = RTM_GETQDISC,
277 .nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
278 .t.tcm_family = AF_UNSPEC,
279 .t.tcm_ifindex = ifindex,
280 };
281 int seq = time(NULL);
282
283 req.nlh.nlmsg_seq = seq;
284 if (send(sock, &req, req.nlh.nlmsg_len, 0) < 0)
285 return -errno;
286
287 return netlink_recv(sock, nl_pid, seq, __dump_qdisc_nlmsg,
288 dump_qdisc_nlmsg, cookie);
289}
290
291static int __dump_filter_nlmsg(struct nlmsghdr *nlh,
292 dump_nlmsg_t dump_filter_nlmsg,
293 void *cookie)
294{
295 struct nlattr *tb[TCA_MAX + 1], *attr;
296 struct tcmsg *t = NLMSG_DATA(nlh);
297 int len;
298
299 len = nlh->nlmsg_len - NLMSG_LENGTH(sizeof(*t));
300 attr = (struct nlattr *) ((void *) t + NLMSG_ALIGN(sizeof(*t)));
301 if (libbpf_nla_parse(tb, TCA_MAX, attr, len, NULL) != 0)
302 return -LIBBPF_ERRNO__NLPARSE;
303
304 return dump_filter_nlmsg(cookie, t, tb);
305}
306
307static int netlink_get_filter(int sock, unsigned int nl_pid, int ifindex, int handle,
308 dump_nlmsg_t dump_filter_nlmsg, void *cookie)
309{
310 struct {
311 struct nlmsghdr nlh;
312 struct tcmsg t;
313 } req = {
314 .nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg)),
315 .nlh.nlmsg_type = RTM_GETTFILTER,
316 .nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
317 .t.tcm_family = AF_UNSPEC,
318 .t.tcm_ifindex = ifindex,
319 .t.tcm_parent = handle,
320 };
321 int seq = time(NULL);
322
323 req.nlh.nlmsg_seq = seq;
324 if (send(sock, &req, req.nlh.nlmsg_len, 0) < 0)
325 return -errno;
326
327 return netlink_recv(sock, nl_pid, seq, __dump_filter_nlmsg,
328 dump_filter_nlmsg, cookie);
329}
330
331static int __dump_link_nlmsg(struct nlmsghdr *nlh,
332 dump_nlmsg_t dump_link_nlmsg, void *cookie)
333{
334 struct nlattr *tb[IFLA_MAX + 1], *attr;
335 struct ifinfomsg *ifi = NLMSG_DATA(nlh);
336 int len;
337
338 len = nlh->nlmsg_len - NLMSG_LENGTH(sizeof(*ifi));
339 attr = (struct nlattr *) ((void *) ifi + NLMSG_ALIGN(sizeof(*ifi)));
340 if (libbpf_nla_parse(tb, IFLA_MAX, attr, len, NULL) != 0)
341 return -LIBBPF_ERRNO__NLPARSE;
342
343 return dump_link_nlmsg(cookie, ifi, tb);
344}
345
346static int netlink_get_link(int sock, unsigned int nl_pid,
347 dump_nlmsg_t dump_link_nlmsg, void *cookie)
348{
349 struct {
350 struct nlmsghdr nlh;
351 struct ifinfomsg ifm;
352 } req = {
353 .nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
354 .nlh.nlmsg_type = RTM_GETLINK,
355 .nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,
356 .ifm.ifi_family = AF_PACKET,
357 };
358 int seq = time(NULL);
359
360 req.nlh.nlmsg_seq = seq;
361 if (send(sock, &req, req.nlh.nlmsg_len, 0) < 0)
362 return -errno;
363
364 return netlink_recv(sock, nl_pid, seq, __dump_link_nlmsg,
365 dump_link_nlmsg, cookie);
366}
367
368static int dump_link_nlmsg(void *cookie, void *msg, struct nlattr **tb)
369{
370 struct bpf_netdev_t *netinfo = cookie;
371 struct ifinfomsg *ifinfo = msg;
372 struct ip_devname_ifindex *tmp;
373
374 if (netinfo->filter_idx > 0 && netinfo->filter_idx != ifinfo->ifi_index)
375 return 0;
376
377 if (netinfo->used_len == netinfo->array_len) {
378 tmp = realloc(netinfo->devices,
379 (netinfo->array_len + 16) * sizeof(struct ip_devname_ifindex));
380 if (!tmp)
381 return -ENOMEM;
382
383 netinfo->devices = tmp;
384 netinfo->array_len += 16;
385 }
386 netinfo->devices[netinfo->used_len].ifindex = ifinfo->ifi_index;
387 snprintf(netinfo->devices[netinfo->used_len].devname,
388 sizeof(netinfo->devices[netinfo->used_len].devname),
389 "%s",
390 tb[IFLA_IFNAME]
391 ? libbpf_nla_getattr_str(tb[IFLA_IFNAME])
392 : "");
393 netinfo->used_len++;
394
395 return do_xdp_dump(ifinfo, tb);
396}
397
398static int dump_class_qdisc_nlmsg(void *cookie, void *msg, struct nlattr **tb)
399{
400 struct bpf_tcinfo_t *tcinfo = cookie;
401 struct tcmsg *info = msg;
402 struct tc_kind_handle *tmp;
403
404 if (tcinfo->is_qdisc) {
405 /* skip clsact qdisc */
406 if (tb[TCA_KIND] &&
407 strcmp(libbpf_nla_data(tb[TCA_KIND]), "clsact") == 0)
408 return 0;
409 if (info->tcm_handle == 0)
410 return 0;
411 }
412
413 if (tcinfo->used_len == tcinfo->array_len) {
414 tmp = realloc(tcinfo->handle_array,
415 (tcinfo->array_len + 16) * sizeof(struct tc_kind_handle));
416 if (!tmp)
417 return -ENOMEM;
418
419 tcinfo->handle_array = tmp;
420 tcinfo->array_len += 16;
421 }
422 tcinfo->handle_array[tcinfo->used_len].handle = info->tcm_handle;
423 snprintf(tcinfo->handle_array[tcinfo->used_len].kind,
424 sizeof(tcinfo->handle_array[tcinfo->used_len].kind),
425 "%s",
426 tb[TCA_KIND]
427 ? libbpf_nla_getattr_str(tb[TCA_KIND])
428 : "unknown");
429 tcinfo->used_len++;
430
431 return 0;
432}
433
434static int dump_filter_nlmsg(void *cookie, void *msg, struct nlattr **tb)
435{
436 const struct bpf_filter_t *filter_info = cookie;
437
438 return do_filter_dump((struct tcmsg *)msg, tb, filter_info->kind,
439 filter_info->devname, filter_info->ifindex);
440}
441
442static int __show_dev_tc_bpf_name(__u32 id, char *name, size_t len)
443{
444 struct bpf_prog_info info = {};
445 __u32 ilen = sizeof(info);
446 int fd, ret;
447
448 fd = bpf_prog_get_fd_by_id(id);
449 if (fd < 0)
450 return fd;
451 ret = bpf_obj_get_info_by_fd(fd, &info, &ilen);
452 if (ret < 0)
453 goto out;
454 ret = -ENOENT;
455 if (info.name[0]) {
456 get_prog_full_name(&info, fd, name, len);
457 ret = 0;
458 }
459out:
460 close(fd);
461 return ret;
462}
463
464static void __show_dev_tc_bpf(const struct ip_devname_ifindex *dev,
465 const enum bpf_attach_type loc)
466{
467 __u32 prog_flags[64] = {}, link_flags[64] = {}, i, j;
468 __u32 prog_ids[64] = {}, link_ids[64] = {};
469 LIBBPF_OPTS(bpf_prog_query_opts, optq);
470 char prog_name[MAX_PROG_FULL_NAME];
471 int ret;
472
473 optq.prog_ids = prog_ids;
474 optq.prog_attach_flags = prog_flags;
475 optq.link_ids = link_ids;
476 optq.link_attach_flags = link_flags;
477 optq.count = ARRAY_SIZE(prog_ids);
478
479 ret = bpf_prog_query_opts(dev->ifindex, loc, &optq);
480 if (ret)
481 return;
482 for (i = 0; i < optq.count; i++) {
483 NET_START_OBJECT;
484 NET_DUMP_STR("devname", "%s", dev->devname);
485 NET_DUMP_UINT("ifindex", "(%u)", (unsigned int)dev->ifindex);
486 NET_DUMP_STR("kind", " %s", attach_loc_strings[loc]);
487 ret = __show_dev_tc_bpf_name(prog_ids[i], prog_name,
488 sizeof(prog_name));
489 if (!ret)
490 NET_DUMP_STR("name", " %s", prog_name);
491 NET_DUMP_UINT("prog_id", " prog_id %u ", prog_ids[i]);
492 if (prog_flags[i] || json_output) {
493 NET_START_ARRAY("prog_flags", "%s ");
494 for (j = 0; prog_flags[i] && j < 32; j++) {
495 if (!(prog_flags[i] & (1U << j)))
496 continue;
497 NET_DUMP_UINT_ONLY(1U << j);
498 }
499 NET_END_ARRAY("");
500 }
501 if (link_ids[i] || json_output) {
502 NET_DUMP_UINT("link_id", "link_id %u ", link_ids[i]);
503 if (link_flags[i] || json_output) {
504 NET_START_ARRAY("link_flags", "%s ");
505 for (j = 0; link_flags[i] && j < 32; j++) {
506 if (!(link_flags[i] & (1U << j)))
507 continue;
508 NET_DUMP_UINT_ONLY(1U << j);
509 }
510 NET_END_ARRAY("");
511 }
512 }
513 NET_END_OBJECT_FINAL;
514 }
515}
516
517static void show_dev_tc_bpf(struct ip_devname_ifindex *dev)
518{
519 __show_dev_tc_bpf(dev, BPF_TCX_INGRESS);
520 __show_dev_tc_bpf(dev, BPF_TCX_EGRESS);
521
522 __show_dev_tc_bpf(dev, BPF_NETKIT_PRIMARY);
523 __show_dev_tc_bpf(dev, BPF_NETKIT_PEER);
524}
525
526static int show_dev_tc_bpf_classic(int sock, unsigned int nl_pid,
527 struct ip_devname_ifindex *dev)
528{
529 struct bpf_filter_t filter_info;
530 struct bpf_tcinfo_t tcinfo;
531 int i, handle, ret = 0;
532
533 tcinfo.handle_array = NULL;
534 tcinfo.used_len = 0;
535 tcinfo.array_len = 0;
536
537 tcinfo.is_qdisc = false;
538 ret = netlink_get_class(sock, nl_pid, dev->ifindex,
539 dump_class_qdisc_nlmsg, &tcinfo);
540 if (ret)
541 goto out;
542
543 tcinfo.is_qdisc = true;
544 ret = netlink_get_qdisc(sock, nl_pid, dev->ifindex,
545 dump_class_qdisc_nlmsg, &tcinfo);
546 if (ret)
547 goto out;
548
549 filter_info.devname = dev->devname;
550 filter_info.ifindex = dev->ifindex;
551 for (i = 0; i < tcinfo.used_len; i++) {
552 filter_info.kind = tcinfo.handle_array[i].kind;
553 ret = netlink_get_filter(sock, nl_pid, dev->ifindex,
554 tcinfo.handle_array[i].handle,
555 dump_filter_nlmsg, &filter_info);
556 if (ret)
557 goto out;
558 }
559
560 /* root, ingress and egress handle */
561 handle = TC_H_ROOT;
562 filter_info.kind = "root";
563 ret = netlink_get_filter(sock, nl_pid, dev->ifindex, handle,
564 dump_filter_nlmsg, &filter_info);
565 if (ret)
566 goto out;
567
568 handle = TC_H_MAKE(TC_H_CLSACT, TC_H_MIN_INGRESS);
569 filter_info.kind = "clsact/ingress";
570 ret = netlink_get_filter(sock, nl_pid, dev->ifindex, handle,
571 dump_filter_nlmsg, &filter_info);
572 if (ret)
573 goto out;
574
575 handle = TC_H_MAKE(TC_H_CLSACT, TC_H_MIN_EGRESS);
576 filter_info.kind = "clsact/egress";
577 ret = netlink_get_filter(sock, nl_pid, dev->ifindex, handle,
578 dump_filter_nlmsg, &filter_info);
579 if (ret)
580 goto out;
581
582out:
583 free(tcinfo.handle_array);
584 return 0;
585}
586
587static int query_flow_dissector(struct bpf_attach_info *attach_info)
588{
589 __u32 attach_flags;
590 __u32 prog_ids[1];
591 __u32 prog_cnt;
592 int err;
593 int fd;
594
595 fd = open("/proc/self/ns/net", O_RDONLY);
596 if (fd < 0) {
597 p_err("can't open /proc/self/ns/net: %s",
598 strerror(errno));
599 return -1;
600 }
601 prog_cnt = ARRAY_SIZE(prog_ids);
602 err = bpf_prog_query(fd, BPF_FLOW_DISSECTOR, 0,
603 &attach_flags, prog_ids, &prog_cnt);
604 close(fd);
605 if (err) {
606 if (err == -EINVAL) {
607 /* Older kernel's don't support querying
608 * flow dissector programs.
609 */
610 errno = 0;
611 return 0;
612 }
613 p_err("can't query prog: %s", strerror(-err));
614 return -1;
615 }
616
617 if (prog_cnt == 1)
618 attach_info->flow_dissector_id = prog_ids[0];
619
620 return 0;
621}
622
623static int net_parse_dev(int *argc, char ***argv)
624{
625 int ifindex;
626
627 if (is_prefix(**argv, "dev")) {
628 NEXT_ARGP();
629
630 ifindex = if_nametoindex(**argv);
631 if (!ifindex)
632 p_err("invalid devname %s", **argv);
633
634 NEXT_ARGP();
635 } else {
636 p_err("expected 'dev', got: '%s'?", **argv);
637 return -1;
638 }
639
640 return ifindex;
641}
642
643static int do_attach_detach_xdp(int progfd, enum net_attach_type attach_type,
644 int ifindex, bool overwrite)
645{
646 __u32 flags = 0;
647
648 if (!overwrite)
649 flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
650 if (attach_type == NET_ATTACH_TYPE_XDP_GENERIC)
651 flags |= XDP_FLAGS_SKB_MODE;
652 if (attach_type == NET_ATTACH_TYPE_XDP_DRIVER)
653 flags |= XDP_FLAGS_DRV_MODE;
654 if (attach_type == NET_ATTACH_TYPE_XDP_OFFLOAD)
655 flags |= XDP_FLAGS_HW_MODE;
656
657 return bpf_xdp_attach(ifindex, progfd, flags, NULL);
658}
659
660static int get_tcx_type(enum net_attach_type attach_type)
661{
662 switch (attach_type) {
663 case NET_ATTACH_TYPE_TCX_INGRESS:
664 return BPF_TCX_INGRESS;
665 case NET_ATTACH_TYPE_TCX_EGRESS:
666 return BPF_TCX_EGRESS;
667 default:
668 return -1;
669 }
670}
671
672static int do_attach_tcx(int progfd, enum net_attach_type attach_type, int ifindex, bool prepend)
673{
674 int type = get_tcx_type(attach_type);
675
676 if (prepend) {
677 LIBBPF_OPTS(bpf_prog_attach_opts, opts,
678 .flags = BPF_F_BEFORE
679 );
680 return bpf_prog_attach_opts(progfd, ifindex, type, &opts);
681 }
682 return bpf_prog_attach(progfd, ifindex, type, 0);
683}
684
685static int do_detach_tcx(int targetfd, enum net_attach_type attach_type)
686{
687 int type = get_tcx_type(attach_type);
688
689 return bpf_prog_detach(targetfd, type);
690}
691
692static int do_attach(int argc, char **argv)
693{
694 enum net_attach_type attach_type;
695 int progfd, ifindex, err = 0;
696 bool overwrite = false;
697 bool prepend = false;
698
699 /* parse attach args */
700 if (!REQ_ARGS(5))
701 return -EINVAL;
702
703 attach_type = parse_attach_type(*argv);
704 if (attach_type == net_attach_type_size) {
705 p_err("invalid net attach/detach type: %s", *argv);
706 return -EINVAL;
707 }
708 NEXT_ARG();
709
710 progfd = prog_parse_fd(&argc, &argv);
711 if (progfd < 0)
712 return -EINVAL;
713
714 ifindex = net_parse_dev(&argc, &argv);
715 if (ifindex < 1) {
716 err = -EINVAL;
717 goto cleanup;
718 }
719
720 if (argc) {
721 if (is_prefix(*argv, "overwrite")) {
722 if (attach_type != NET_ATTACH_TYPE_XDP &&
723 attach_type != NET_ATTACH_TYPE_XDP_GENERIC &&
724 attach_type != NET_ATTACH_TYPE_XDP_DRIVER &&
725 attach_type != NET_ATTACH_TYPE_XDP_OFFLOAD) {
726 p_err("'overwrite' is only supported for xdp types");
727 err = -EINVAL;
728 goto cleanup;
729 }
730 overwrite = true;
731 } else if (is_prefix(*argv, "prepend")) {
732 if (attach_type != NET_ATTACH_TYPE_TCX_INGRESS &&
733 attach_type != NET_ATTACH_TYPE_TCX_EGRESS) {
734 p_err("'prepend' is only supported for tcx_ingress/tcx_egress");
735 err = -EINVAL;
736 goto cleanup;
737 }
738 prepend = true;
739 } else {
740 p_err("expected 'overwrite' or 'prepend', got: '%s'?", *argv);
741 err = -EINVAL;
742 goto cleanup;
743 }
744 }
745
746 switch (attach_type) {
747 /* attach xdp prog */
748 case NET_ATTACH_TYPE_XDP:
749 case NET_ATTACH_TYPE_XDP_GENERIC:
750 case NET_ATTACH_TYPE_XDP_DRIVER:
751 case NET_ATTACH_TYPE_XDP_OFFLOAD:
752 err = do_attach_detach_xdp(progfd, attach_type, ifindex, overwrite);
753 break;
754 /* attach tcx prog */
755 case NET_ATTACH_TYPE_TCX_INGRESS:
756 case NET_ATTACH_TYPE_TCX_EGRESS:
757 err = do_attach_tcx(progfd, attach_type, ifindex, prepend);
758 break;
759 default:
760 break;
761 }
762
763 if (err) {
764 p_err("interface %s attach failed: %s",
765 attach_type_strings[attach_type], strerror(-err));
766 goto cleanup;
767 }
768
769 if (json_output)
770 jsonw_null(json_wtr);
771cleanup:
772 close(progfd);
773 return err;
774}
775
776static int do_detach(int argc, char **argv)
777{
778 enum net_attach_type attach_type;
779 int progfd, ifindex, err = 0;
780
781 /* parse detach args */
782 if (!REQ_ARGS(3))
783 return -EINVAL;
784
785 attach_type = parse_attach_type(*argv);
786 if (attach_type == net_attach_type_size) {
787 p_err("invalid net attach/detach type: %s", *argv);
788 return -EINVAL;
789 }
790 NEXT_ARG();
791
792 ifindex = net_parse_dev(&argc, &argv);
793 if (ifindex < 1)
794 return -EINVAL;
795
796 switch (attach_type) {
797 /* detach xdp prog */
798 case NET_ATTACH_TYPE_XDP:
799 case NET_ATTACH_TYPE_XDP_GENERIC:
800 case NET_ATTACH_TYPE_XDP_DRIVER:
801 case NET_ATTACH_TYPE_XDP_OFFLOAD:
802 progfd = -1;
803 err = do_attach_detach_xdp(progfd, attach_type, ifindex, NULL);
804 break;
805 /* detach tcx prog */
806 case NET_ATTACH_TYPE_TCX_INGRESS:
807 case NET_ATTACH_TYPE_TCX_EGRESS:
808 err = do_detach_tcx(ifindex, attach_type);
809 break;
810 default:
811 break;
812 }
813
814 if (err < 0) {
815 p_err("interface %s detach failed: %s",
816 attach_type_strings[attach_type], strerror(-err));
817 return err;
818 }
819
820 if (json_output)
821 jsonw_null(json_wtr);
822
823 return 0;
824}
825
826static int netfilter_link_compar(const void *a, const void *b)
827{
828 const struct bpf_link_info *nfa = a;
829 const struct bpf_link_info *nfb = b;
830 int delta;
831
832 delta = nfa->netfilter.pf - nfb->netfilter.pf;
833 if (delta)
834 return delta;
835
836 delta = nfa->netfilter.hooknum - nfb->netfilter.hooknum;
837 if (delta)
838 return delta;
839
840 if (nfa->netfilter.priority < nfb->netfilter.priority)
841 return -1;
842 if (nfa->netfilter.priority > nfb->netfilter.priority)
843 return 1;
844
845 return nfa->netfilter.flags - nfb->netfilter.flags;
846}
847
848static void show_link_netfilter(void)
849{
850 unsigned int nf_link_len = 0, nf_link_count = 0;
851 struct bpf_link_info *nf_link_info = NULL;
852 __u32 id = 0;
853
854 while (true) {
855 struct bpf_link_info info;
856 int fd, err;
857 __u32 len;
858
859 err = bpf_link_get_next_id(id, &id);
860 if (err) {
861 if (errno == ENOENT)
862 break;
863 p_err("can't get next link: %s (id %u)", strerror(errno), id);
864 break;
865 }
866
867 fd = bpf_link_get_fd_by_id(id);
868 if (fd < 0) {
869 p_err("can't get link by id (%u): %s", id, strerror(errno));
870 continue;
871 }
872
873 memset(&info, 0, sizeof(info));
874 len = sizeof(info);
875
876 err = bpf_link_get_info_by_fd(fd, &info, &len);
877
878 close(fd);
879
880 if (err) {
881 p_err("can't get link info for fd %d: %s", fd, strerror(errno));
882 continue;
883 }
884
885 if (info.type != BPF_LINK_TYPE_NETFILTER)
886 continue;
887
888 if (nf_link_count >= nf_link_len) {
889 static const unsigned int max_link_count = INT_MAX / sizeof(info);
890 struct bpf_link_info *expand;
891
892 if (nf_link_count > max_link_count) {
893 p_err("cannot handle more than %u links\n", max_link_count);
894 break;
895 }
896
897 nf_link_len += 16;
898
899 expand = realloc(nf_link_info, nf_link_len * sizeof(info));
900 if (!expand) {
901 p_err("realloc: %s", strerror(errno));
902 break;
903 }
904
905 nf_link_info = expand;
906 }
907
908 nf_link_info[nf_link_count] = info;
909 nf_link_count++;
910 }
911
912 if (!nf_link_info)
913 return;
914
915 qsort(nf_link_info, nf_link_count, sizeof(*nf_link_info), netfilter_link_compar);
916
917 for (id = 0; id < nf_link_count; id++) {
918 NET_START_OBJECT;
919 if (json_output)
920 netfilter_dump_json(&nf_link_info[id], json_wtr);
921 else
922 netfilter_dump_plain(&nf_link_info[id]);
923
924 NET_DUMP_UINT("id", " prog_id %u", nf_link_info[id].prog_id);
925 NET_END_OBJECT;
926 }
927
928 free(nf_link_info);
929}
930
931static int do_show(int argc, char **argv)
932{
933 struct bpf_attach_info attach_info = {};
934 int i, sock, ret, filter_idx = -1;
935 struct bpf_netdev_t dev_array;
936 unsigned int nl_pid = 0;
937 char err_buf[256];
938
939 if (argc == 2) {
940 filter_idx = net_parse_dev(&argc, &argv);
941 if (filter_idx < 1)
942 return -1;
943 } else if (argc != 0) {
944 usage();
945 }
946
947 ret = query_flow_dissector(&attach_info);
948 if (ret)
949 return -1;
950
951 sock = netlink_open(&nl_pid);
952 if (sock < 0) {
953 fprintf(stderr, "failed to open netlink sock\n");
954 return -1;
955 }
956
957 dev_array.devices = NULL;
958 dev_array.used_len = 0;
959 dev_array.array_len = 0;
960 dev_array.filter_idx = filter_idx;
961
962 if (json_output)
963 jsonw_start_array(json_wtr);
964 NET_START_OBJECT;
965 NET_START_ARRAY("xdp", "%s:\n");
966 ret = netlink_get_link(sock, nl_pid, dump_link_nlmsg, &dev_array);
967 NET_END_ARRAY("\n");
968
969 if (!ret) {
970 NET_START_ARRAY("tc", "%s:\n");
971 for (i = 0; i < dev_array.used_len; i++) {
972 show_dev_tc_bpf(&dev_array.devices[i]);
973 ret = show_dev_tc_bpf_classic(sock, nl_pid,
974 &dev_array.devices[i]);
975 if (ret)
976 break;
977 }
978 NET_END_ARRAY("\n");
979 }
980
981 NET_START_ARRAY("flow_dissector", "%s:\n");
982 if (attach_info.flow_dissector_id > 0)
983 NET_DUMP_UINT("id", "id %u", attach_info.flow_dissector_id);
984 NET_END_ARRAY("\n");
985
986 NET_START_ARRAY("netfilter", "%s:\n");
987 show_link_netfilter();
988 NET_END_ARRAY("\n");
989
990 NET_END_OBJECT;
991 if (json_output)
992 jsonw_end_array(json_wtr);
993
994 if (ret) {
995 if (json_output)
996 jsonw_null(json_wtr);
997 libbpf_strerror(ret, err_buf, sizeof(err_buf));
998 fprintf(stderr, "Error: %s\n", err_buf);
999 }
1000 free(dev_array.devices);
1001 close(sock);
1002 return ret;
1003}
1004
1005static int do_help(int argc, char **argv)
1006{
1007 if (json_output) {
1008 jsonw_null(json_wtr);
1009 return 0;
1010 }
1011
1012 fprintf(stderr,
1013 "Usage: %1$s %2$s { show | list } [dev <devname>]\n"
1014 " %1$s %2$s attach ATTACH_TYPE PROG dev <devname> [ overwrite | prepend ]\n"
1015 " %1$s %2$s detach ATTACH_TYPE dev <devname>\n"
1016 " %1$s %2$s help\n"
1017 "\n"
1018 " " HELP_SPEC_PROGRAM "\n"
1019 " ATTACH_TYPE := { xdp | xdpgeneric | xdpdrv | xdpoffload | tcx_ingress\n"
1020 " | tcx_egress }\n"
1021 " " HELP_SPEC_OPTIONS " }\n"
1022 "\n"
1023 "Note: Only xdp, tcx, tc, netkit, flow_dissector and netfilter attachments\n"
1024 " are currently supported.\n"
1025 " For progs attached to cgroups, use \"bpftool cgroup\"\n"
1026 " to dump program attachments. For program types\n"
1027 " sk_{filter,skb,msg,reuseport} and lwt/seg6, please\n"
1028 " consult iproute2.\n"
1029 "",
1030 bin_name, argv[-2]);
1031
1032 return 0;
1033}
1034
1035static const struct cmd cmds[] = {
1036 { "show", do_show },
1037 { "list", do_show },
1038 { "attach", do_attach },
1039 { "detach", do_detach },
1040 { "help", do_help },
1041 { 0 }
1042};
1043
1044int do_net(int argc, char **argv)
1045{
1046 return cmd_select(cmds, argc, argv, do_help);
1047}