1019 lines · c
1// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)2// Copyright (C) 2018 Facebook3 4#ifndef _GNU_SOURCE5#define _GNU_SOURCE6#endif7#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_NETLINK28#define SOL_NETLINK 27029#endif30 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[4096];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 ret = 0;206done:207 return ret;208}209 210static int __dump_class_nlmsg(struct nlmsghdr *nlh,211 dump_nlmsg_t dump_class_nlmsg,212 void *cookie)213{214 struct nlattr *tb[TCA_MAX + 1], *attr;215 struct tcmsg *t = NLMSG_DATA(nlh);216 int len;217 218 len = nlh->nlmsg_len - NLMSG_LENGTH(sizeof(*t));219 attr = (struct nlattr *) ((void *) t + NLMSG_ALIGN(sizeof(*t)));220 if (libbpf_nla_parse(tb, TCA_MAX, attr, len, NULL) != 0)221 return -LIBBPF_ERRNO__NLPARSE;222 223 return dump_class_nlmsg(cookie, t, tb);224}225 226static int netlink_get_class(int sock, unsigned int nl_pid, int ifindex,227 dump_nlmsg_t dump_class_nlmsg, void *cookie)228{229 struct {230 struct nlmsghdr nlh;231 struct tcmsg t;232 } req = {233 .nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg)),234 .nlh.nlmsg_type = RTM_GETTCLASS,235 .nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,236 .t.tcm_family = AF_UNSPEC,237 .t.tcm_ifindex = ifindex,238 };239 int seq = time(NULL);240 241 req.nlh.nlmsg_seq = seq;242 if (send(sock, &req, req.nlh.nlmsg_len, 0) < 0)243 return -errno;244 245 return netlink_recv(sock, nl_pid, seq, __dump_class_nlmsg,246 dump_class_nlmsg, cookie);247}248 249static int __dump_qdisc_nlmsg(struct nlmsghdr *nlh,250 dump_nlmsg_t dump_qdisc_nlmsg,251 void *cookie)252{253 struct nlattr *tb[TCA_MAX + 1], *attr;254 struct tcmsg *t = NLMSG_DATA(nlh);255 int len;256 257 len = nlh->nlmsg_len - NLMSG_LENGTH(sizeof(*t));258 attr = (struct nlattr *) ((void *) t + NLMSG_ALIGN(sizeof(*t)));259 if (libbpf_nla_parse(tb, TCA_MAX, attr, len, NULL) != 0)260 return -LIBBPF_ERRNO__NLPARSE;261 262 return dump_qdisc_nlmsg(cookie, t, tb);263}264 265static int netlink_get_qdisc(int sock, unsigned int nl_pid, int ifindex,266 dump_nlmsg_t dump_qdisc_nlmsg, void *cookie)267{268 struct {269 struct nlmsghdr nlh;270 struct tcmsg t;271 } req = {272 .nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg)),273 .nlh.nlmsg_type = RTM_GETQDISC,274 .nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,275 .t.tcm_family = AF_UNSPEC,276 .t.tcm_ifindex = ifindex,277 };278 int seq = time(NULL);279 280 req.nlh.nlmsg_seq = seq;281 if (send(sock, &req, req.nlh.nlmsg_len, 0) < 0)282 return -errno;283 284 return netlink_recv(sock, nl_pid, seq, __dump_qdisc_nlmsg,285 dump_qdisc_nlmsg, cookie);286}287 288static int __dump_filter_nlmsg(struct nlmsghdr *nlh,289 dump_nlmsg_t dump_filter_nlmsg,290 void *cookie)291{292 struct nlattr *tb[TCA_MAX + 1], *attr;293 struct tcmsg *t = NLMSG_DATA(nlh);294 int len;295 296 len = nlh->nlmsg_len - NLMSG_LENGTH(sizeof(*t));297 attr = (struct nlattr *) ((void *) t + NLMSG_ALIGN(sizeof(*t)));298 if (libbpf_nla_parse(tb, TCA_MAX, attr, len, NULL) != 0)299 return -LIBBPF_ERRNO__NLPARSE;300 301 return dump_filter_nlmsg(cookie, t, tb);302}303 304static int netlink_get_filter(int sock, unsigned int nl_pid, int ifindex, int handle,305 dump_nlmsg_t dump_filter_nlmsg, void *cookie)306{307 struct {308 struct nlmsghdr nlh;309 struct tcmsg t;310 } req = {311 .nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct tcmsg)),312 .nlh.nlmsg_type = RTM_GETTFILTER,313 .nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,314 .t.tcm_family = AF_UNSPEC,315 .t.tcm_ifindex = ifindex,316 .t.tcm_parent = handle,317 };318 int seq = time(NULL);319 320 req.nlh.nlmsg_seq = seq;321 if (send(sock, &req, req.nlh.nlmsg_len, 0) < 0)322 return -errno;323 324 return netlink_recv(sock, nl_pid, seq, __dump_filter_nlmsg,325 dump_filter_nlmsg, cookie);326}327 328static int __dump_link_nlmsg(struct nlmsghdr *nlh,329 dump_nlmsg_t dump_link_nlmsg, void *cookie)330{331 struct nlattr *tb[IFLA_MAX + 1], *attr;332 struct ifinfomsg *ifi = NLMSG_DATA(nlh);333 int len;334 335 len = nlh->nlmsg_len - NLMSG_LENGTH(sizeof(*ifi));336 attr = (struct nlattr *) ((void *) ifi + NLMSG_ALIGN(sizeof(*ifi)));337 if (libbpf_nla_parse(tb, IFLA_MAX, attr, len, NULL) != 0)338 return -LIBBPF_ERRNO__NLPARSE;339 340 return dump_link_nlmsg(cookie, ifi, tb);341}342 343static int netlink_get_link(int sock, unsigned int nl_pid,344 dump_nlmsg_t dump_link_nlmsg, void *cookie)345{346 struct {347 struct nlmsghdr nlh;348 struct ifinfomsg ifm;349 } req = {350 .nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)),351 .nlh.nlmsg_type = RTM_GETLINK,352 .nlh.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST,353 .ifm.ifi_family = AF_PACKET,354 };355 int seq = time(NULL);356 357 req.nlh.nlmsg_seq = seq;358 if (send(sock, &req, req.nlh.nlmsg_len, 0) < 0)359 return -errno;360 361 return netlink_recv(sock, nl_pid, seq, __dump_link_nlmsg,362 dump_link_nlmsg, cookie);363}364 365static int dump_link_nlmsg(void *cookie, void *msg, struct nlattr **tb)366{367 struct bpf_netdev_t *netinfo = cookie;368 struct ifinfomsg *ifinfo = msg;369 370 if (netinfo->filter_idx > 0 && netinfo->filter_idx != ifinfo->ifi_index)371 return 0;372 373 if (netinfo->used_len == netinfo->array_len) {374 netinfo->devices = realloc(netinfo->devices,375 (netinfo->array_len + 16) *376 sizeof(struct ip_devname_ifindex));377 if (!netinfo->devices)378 return -ENOMEM;379 380 netinfo->array_len += 16;381 }382 netinfo->devices[netinfo->used_len].ifindex = ifinfo->ifi_index;383 snprintf(netinfo->devices[netinfo->used_len].devname,384 sizeof(netinfo->devices[netinfo->used_len].devname),385 "%s",386 tb[IFLA_IFNAME]387 ? libbpf_nla_getattr_str(tb[IFLA_IFNAME])388 : "");389 netinfo->used_len++;390 391 return do_xdp_dump(ifinfo, tb);392}393 394static int dump_class_qdisc_nlmsg(void *cookie, void *msg, struct nlattr **tb)395{396 struct bpf_tcinfo_t *tcinfo = cookie;397 struct tcmsg *info = msg;398 399 if (tcinfo->is_qdisc) {400 /* skip clsact qdisc */401 if (tb[TCA_KIND] &&402 strcmp(libbpf_nla_data(tb[TCA_KIND]), "clsact") == 0)403 return 0;404 if (info->tcm_handle == 0)405 return 0;406 }407 408 if (tcinfo->used_len == tcinfo->array_len) {409 tcinfo->handle_array = realloc(tcinfo->handle_array,410 (tcinfo->array_len + 16) * sizeof(struct tc_kind_handle));411 if (!tcinfo->handle_array)412 return -ENOMEM;413 414 tcinfo->array_len += 16;415 }416 tcinfo->handle_array[tcinfo->used_len].handle = info->tcm_handle;417 snprintf(tcinfo->handle_array[tcinfo->used_len].kind,418 sizeof(tcinfo->handle_array[tcinfo->used_len].kind),419 "%s",420 tb[TCA_KIND]421 ? libbpf_nla_getattr_str(tb[TCA_KIND])422 : "unknown");423 tcinfo->used_len++;424 425 return 0;426}427 428static int dump_filter_nlmsg(void *cookie, void *msg, struct nlattr **tb)429{430 const struct bpf_filter_t *filter_info = cookie;431 432 return do_filter_dump((struct tcmsg *)msg, tb, filter_info->kind,433 filter_info->devname, filter_info->ifindex);434}435 436static int __show_dev_tc_bpf_name(__u32 id, char *name, size_t len)437{438 struct bpf_prog_info info = {};439 __u32 ilen = sizeof(info);440 int fd, ret;441 442 fd = bpf_prog_get_fd_by_id(id);443 if (fd < 0)444 return fd;445 ret = bpf_obj_get_info_by_fd(fd, &info, &ilen);446 if (ret < 0)447 goto out;448 ret = -ENOENT;449 if (info.name[0]) {450 get_prog_full_name(&info, fd, name, len);451 ret = 0;452 }453out:454 close(fd);455 return ret;456}457 458static void __show_dev_tc_bpf(const struct ip_devname_ifindex *dev,459 const enum bpf_attach_type loc)460{461 __u32 prog_flags[64] = {}, link_flags[64] = {}, i, j;462 __u32 prog_ids[64] = {}, link_ids[64] = {};463 LIBBPF_OPTS(bpf_prog_query_opts, optq);464 char prog_name[MAX_PROG_FULL_NAME];465 int ret;466 467 optq.prog_ids = prog_ids;468 optq.prog_attach_flags = prog_flags;469 optq.link_ids = link_ids;470 optq.link_attach_flags = link_flags;471 optq.count = ARRAY_SIZE(prog_ids);472 473 ret = bpf_prog_query_opts(dev->ifindex, loc, &optq);474 if (ret)475 return;476 for (i = 0; i < optq.count; i++) {477 NET_START_OBJECT;478 NET_DUMP_STR("devname", "%s", dev->devname);479 NET_DUMP_UINT("ifindex", "(%u)", dev->ifindex);480 NET_DUMP_STR("kind", " %s", attach_loc_strings[loc]);481 ret = __show_dev_tc_bpf_name(prog_ids[i], prog_name,482 sizeof(prog_name));483 if (!ret)484 NET_DUMP_STR("name", " %s", prog_name);485 NET_DUMP_UINT("prog_id", " prog_id %u ", prog_ids[i]);486 if (prog_flags[i] || json_output) {487 NET_START_ARRAY("prog_flags", "%s ");488 for (j = 0; prog_flags[i] && j < 32; j++) {489 if (!(prog_flags[i] & (1U << j)))490 continue;491 NET_DUMP_UINT_ONLY(1U << j);492 }493 NET_END_ARRAY("");494 }495 if (link_ids[i] || json_output) {496 NET_DUMP_UINT("link_id", "link_id %u ", link_ids[i]);497 if (link_flags[i] || json_output) {498 NET_START_ARRAY("link_flags", "%s ");499 for (j = 0; link_flags[i] && j < 32; j++) {500 if (!(link_flags[i] & (1U << j)))501 continue;502 NET_DUMP_UINT_ONLY(1U << j);503 }504 NET_END_ARRAY("");505 }506 }507 NET_END_OBJECT_FINAL;508 }509}510 511static void show_dev_tc_bpf(struct ip_devname_ifindex *dev)512{513 __show_dev_tc_bpf(dev, BPF_TCX_INGRESS);514 __show_dev_tc_bpf(dev, BPF_TCX_EGRESS);515 516 __show_dev_tc_bpf(dev, BPF_NETKIT_PRIMARY);517 __show_dev_tc_bpf(dev, BPF_NETKIT_PEER);518}519 520static int show_dev_tc_bpf_classic(int sock, unsigned int nl_pid,521 struct ip_devname_ifindex *dev)522{523 struct bpf_filter_t filter_info;524 struct bpf_tcinfo_t tcinfo;525 int i, handle, ret = 0;526 527 tcinfo.handle_array = NULL;528 tcinfo.used_len = 0;529 tcinfo.array_len = 0;530 531 tcinfo.is_qdisc = false;532 ret = netlink_get_class(sock, nl_pid, dev->ifindex,533 dump_class_qdisc_nlmsg, &tcinfo);534 if (ret)535 goto out;536 537 tcinfo.is_qdisc = true;538 ret = netlink_get_qdisc(sock, nl_pid, dev->ifindex,539 dump_class_qdisc_nlmsg, &tcinfo);540 if (ret)541 goto out;542 543 filter_info.devname = dev->devname;544 filter_info.ifindex = dev->ifindex;545 for (i = 0; i < tcinfo.used_len; i++) {546 filter_info.kind = tcinfo.handle_array[i].kind;547 ret = netlink_get_filter(sock, nl_pid, dev->ifindex,548 tcinfo.handle_array[i].handle,549 dump_filter_nlmsg, &filter_info);550 if (ret)551 goto out;552 }553 554 /* root, ingress and egress handle */555 handle = TC_H_ROOT;556 filter_info.kind = "root";557 ret = netlink_get_filter(sock, nl_pid, dev->ifindex, handle,558 dump_filter_nlmsg, &filter_info);559 if (ret)560 goto out;561 562 handle = TC_H_MAKE(TC_H_CLSACT, TC_H_MIN_INGRESS);563 filter_info.kind = "clsact/ingress";564 ret = netlink_get_filter(sock, nl_pid, dev->ifindex, handle,565 dump_filter_nlmsg, &filter_info);566 if (ret)567 goto out;568 569 handle = TC_H_MAKE(TC_H_CLSACT, TC_H_MIN_EGRESS);570 filter_info.kind = "clsact/egress";571 ret = netlink_get_filter(sock, nl_pid, dev->ifindex, handle,572 dump_filter_nlmsg, &filter_info);573 if (ret)574 goto out;575 576out:577 free(tcinfo.handle_array);578 return 0;579}580 581static int query_flow_dissector(struct bpf_attach_info *attach_info)582{583 __u32 attach_flags;584 __u32 prog_ids[1];585 __u32 prog_cnt;586 int err;587 int fd;588 589 fd = open("/proc/self/ns/net", O_RDONLY);590 if (fd < 0) {591 p_err("can't open /proc/self/ns/net: %s",592 strerror(errno));593 return -1;594 }595 prog_cnt = ARRAY_SIZE(prog_ids);596 err = bpf_prog_query(fd, BPF_FLOW_DISSECTOR, 0,597 &attach_flags, prog_ids, &prog_cnt);598 close(fd);599 if (err) {600 if (errno == EINVAL) {601 /* Older kernel's don't support querying602 * flow dissector programs.603 */604 errno = 0;605 return 0;606 }607 p_err("can't query prog: %s", strerror(errno));608 return -1;609 }610 611 if (prog_cnt == 1)612 attach_info->flow_dissector_id = prog_ids[0];613 614 return 0;615}616 617static int net_parse_dev(int *argc, char ***argv)618{619 int ifindex;620 621 if (is_prefix(**argv, "dev")) {622 NEXT_ARGP();623 624 ifindex = if_nametoindex(**argv);625 if (!ifindex)626 p_err("invalid devname %s", **argv);627 628 NEXT_ARGP();629 } else {630 p_err("expected 'dev', got: '%s'?", **argv);631 return -1;632 }633 634 return ifindex;635}636 637static int do_attach_detach_xdp(int progfd, enum net_attach_type attach_type,638 int ifindex, bool overwrite)639{640 __u32 flags = 0;641 642 if (!overwrite)643 flags = XDP_FLAGS_UPDATE_IF_NOEXIST;644 if (attach_type == NET_ATTACH_TYPE_XDP_GENERIC)645 flags |= XDP_FLAGS_SKB_MODE;646 if (attach_type == NET_ATTACH_TYPE_XDP_DRIVER)647 flags |= XDP_FLAGS_DRV_MODE;648 if (attach_type == NET_ATTACH_TYPE_XDP_OFFLOAD)649 flags |= XDP_FLAGS_HW_MODE;650 651 return bpf_xdp_attach(ifindex, progfd, flags, NULL);652}653 654static int get_tcx_type(enum net_attach_type attach_type)655{656 switch (attach_type) {657 case NET_ATTACH_TYPE_TCX_INGRESS:658 return BPF_TCX_INGRESS;659 case NET_ATTACH_TYPE_TCX_EGRESS:660 return BPF_TCX_EGRESS;661 default:662 return -1;663 }664}665 666static int do_attach_tcx(int progfd, enum net_attach_type attach_type, int ifindex)667{668 int type = get_tcx_type(attach_type);669 670 return bpf_prog_attach(progfd, ifindex, type, 0);671}672 673static int do_detach_tcx(int targetfd, enum net_attach_type attach_type)674{675 int type = get_tcx_type(attach_type);676 677 return bpf_prog_detach(targetfd, type);678}679 680static int do_attach(int argc, char **argv)681{682 enum net_attach_type attach_type;683 int progfd, ifindex, err = 0;684 bool overwrite = false;685 686 /* parse attach args */687 if (!REQ_ARGS(5))688 return -EINVAL;689 690 attach_type = parse_attach_type(*argv);691 if (attach_type == net_attach_type_size) {692 p_err("invalid net attach/detach type: %s", *argv);693 return -EINVAL;694 }695 NEXT_ARG();696 697 progfd = prog_parse_fd(&argc, &argv);698 if (progfd < 0)699 return -EINVAL;700 701 ifindex = net_parse_dev(&argc, &argv);702 if (ifindex < 1) {703 err = -EINVAL;704 goto cleanup;705 }706 707 if (argc) {708 if (is_prefix(*argv, "overwrite")) {709 overwrite = true;710 } else {711 p_err("expected 'overwrite', got: '%s'?", *argv);712 err = -EINVAL;713 goto cleanup;714 }715 }716 717 switch (attach_type) {718 /* attach xdp prog */719 case NET_ATTACH_TYPE_XDP:720 case NET_ATTACH_TYPE_XDP_GENERIC:721 case NET_ATTACH_TYPE_XDP_DRIVER:722 case NET_ATTACH_TYPE_XDP_OFFLOAD:723 err = do_attach_detach_xdp(progfd, attach_type, ifindex, overwrite);724 break;725 /* attach tcx prog */726 case NET_ATTACH_TYPE_TCX_INGRESS:727 case NET_ATTACH_TYPE_TCX_EGRESS:728 err = do_attach_tcx(progfd, attach_type, ifindex);729 break;730 default:731 break;732 }733 734 if (err) {735 p_err("interface %s attach failed: %s",736 attach_type_strings[attach_type], strerror(-err));737 goto cleanup;738 }739 740 if (json_output)741 jsonw_null(json_wtr);742cleanup:743 close(progfd);744 return err;745}746 747static int do_detach(int argc, char **argv)748{749 enum net_attach_type attach_type;750 int progfd, ifindex, err = 0;751 752 /* parse detach args */753 if (!REQ_ARGS(3))754 return -EINVAL;755 756 attach_type = parse_attach_type(*argv);757 if (attach_type == net_attach_type_size) {758 p_err("invalid net attach/detach type: %s", *argv);759 return -EINVAL;760 }761 NEXT_ARG();762 763 ifindex = net_parse_dev(&argc, &argv);764 if (ifindex < 1)765 return -EINVAL;766 767 switch (attach_type) {768 /* detach xdp prog */769 case NET_ATTACH_TYPE_XDP:770 case NET_ATTACH_TYPE_XDP_GENERIC:771 case NET_ATTACH_TYPE_XDP_DRIVER:772 case NET_ATTACH_TYPE_XDP_OFFLOAD:773 progfd = -1;774 err = do_attach_detach_xdp(progfd, attach_type, ifindex, NULL);775 break;776 /* detach tcx prog */777 case NET_ATTACH_TYPE_TCX_INGRESS:778 case NET_ATTACH_TYPE_TCX_EGRESS:779 err = do_detach_tcx(ifindex, attach_type);780 break;781 default:782 break;783 }784 785 if (err < 0) {786 p_err("interface %s detach failed: %s",787 attach_type_strings[attach_type], strerror(-err));788 return err;789 }790 791 if (json_output)792 jsonw_null(json_wtr);793 794 return 0;795}796 797static int netfilter_link_compar(const void *a, const void *b)798{799 const struct bpf_link_info *nfa = a;800 const struct bpf_link_info *nfb = b;801 int delta;802 803 delta = nfa->netfilter.pf - nfb->netfilter.pf;804 if (delta)805 return delta;806 807 delta = nfa->netfilter.hooknum - nfb->netfilter.hooknum;808 if (delta)809 return delta;810 811 if (nfa->netfilter.priority < nfb->netfilter.priority)812 return -1;813 if (nfa->netfilter.priority > nfb->netfilter.priority)814 return 1;815 816 return nfa->netfilter.flags - nfb->netfilter.flags;817}818 819static void show_link_netfilter(void)820{821 unsigned int nf_link_len = 0, nf_link_count = 0;822 struct bpf_link_info *nf_link_info = NULL;823 __u32 id = 0;824 825 while (true) {826 struct bpf_link_info info;827 int fd, err;828 __u32 len;829 830 err = bpf_link_get_next_id(id, &id);831 if (err) {832 if (errno == ENOENT)833 break;834 p_err("can't get next link: %s (id %d)", strerror(errno), id);835 break;836 }837 838 fd = bpf_link_get_fd_by_id(id);839 if (fd < 0) {840 p_err("can't get link by id (%u): %s", id, strerror(errno));841 continue;842 }843 844 memset(&info, 0, sizeof(info));845 len = sizeof(info);846 847 err = bpf_link_get_info_by_fd(fd, &info, &len);848 849 close(fd);850 851 if (err) {852 p_err("can't get link info for fd %d: %s", fd, strerror(errno));853 continue;854 }855 856 if (info.type != BPF_LINK_TYPE_NETFILTER)857 continue;858 859 if (nf_link_count >= nf_link_len) {860 static const unsigned int max_link_count = INT_MAX / sizeof(info);861 struct bpf_link_info *expand;862 863 if (nf_link_count > max_link_count) {864 p_err("cannot handle more than %u links\n", max_link_count);865 break;866 }867 868 nf_link_len += 16;869 870 expand = realloc(nf_link_info, nf_link_len * sizeof(info));871 if (!expand) {872 p_err("realloc: %s", strerror(errno));873 break;874 }875 876 nf_link_info = expand;877 }878 879 nf_link_info[nf_link_count] = info;880 nf_link_count++;881 }882 883 if (!nf_link_info)884 return;885 886 qsort(nf_link_info, nf_link_count, sizeof(*nf_link_info), netfilter_link_compar);887 888 for (id = 0; id < nf_link_count; id++) {889 NET_START_OBJECT;890 if (json_output)891 netfilter_dump_json(&nf_link_info[id], json_wtr);892 else893 netfilter_dump_plain(&nf_link_info[id]);894 895 NET_DUMP_UINT("id", " prog_id %u", nf_link_info[id].prog_id);896 NET_END_OBJECT;897 }898 899 free(nf_link_info);900}901 902static int do_show(int argc, char **argv)903{904 struct bpf_attach_info attach_info = {};905 int i, sock, ret, filter_idx = -1;906 struct bpf_netdev_t dev_array;907 unsigned int nl_pid = 0;908 char err_buf[256];909 910 if (argc == 2) {911 filter_idx = net_parse_dev(&argc, &argv);912 if (filter_idx < 1)913 return -1;914 } else if (argc != 0) {915 usage();916 }917 918 ret = query_flow_dissector(&attach_info);919 if (ret)920 return -1;921 922 sock = netlink_open(&nl_pid);923 if (sock < 0) {924 fprintf(stderr, "failed to open netlink sock\n");925 return -1;926 }927 928 dev_array.devices = NULL;929 dev_array.used_len = 0;930 dev_array.array_len = 0;931 dev_array.filter_idx = filter_idx;932 933 if (json_output)934 jsonw_start_array(json_wtr);935 NET_START_OBJECT;936 NET_START_ARRAY("xdp", "%s:\n");937 ret = netlink_get_link(sock, nl_pid, dump_link_nlmsg, &dev_array);938 NET_END_ARRAY("\n");939 940 if (!ret) {941 NET_START_ARRAY("tc", "%s:\n");942 for (i = 0; i < dev_array.used_len; i++) {943 show_dev_tc_bpf(&dev_array.devices[i]);944 ret = show_dev_tc_bpf_classic(sock, nl_pid,945 &dev_array.devices[i]);946 if (ret)947 break;948 }949 NET_END_ARRAY("\n");950 }951 952 NET_START_ARRAY("flow_dissector", "%s:\n");953 if (attach_info.flow_dissector_id > 0)954 NET_DUMP_UINT("id", "id %u", attach_info.flow_dissector_id);955 NET_END_ARRAY("\n");956 957 NET_START_ARRAY("netfilter", "%s:\n");958 show_link_netfilter();959 NET_END_ARRAY("\n");960 961 NET_END_OBJECT;962 if (json_output)963 jsonw_end_array(json_wtr);964 965 if (ret) {966 if (json_output)967 jsonw_null(json_wtr);968 libbpf_strerror(ret, err_buf, sizeof(err_buf));969 fprintf(stderr, "Error: %s\n", err_buf);970 }971 free(dev_array.devices);972 close(sock);973 return ret;974}975 976static int do_help(int argc, char **argv)977{978 if (json_output) {979 jsonw_null(json_wtr);980 return 0;981 }982 983 fprintf(stderr,984 "Usage: %1$s %2$s { show | list } [dev <devname>]\n"985 " %1$s %2$s attach ATTACH_TYPE PROG dev <devname> [ overwrite ]\n"986 " %1$s %2$s detach ATTACH_TYPE dev <devname>\n"987 " %1$s %2$s help\n"988 "\n"989 " " HELP_SPEC_PROGRAM "\n"990 " ATTACH_TYPE := { xdp | xdpgeneric | xdpdrv | xdpoffload | tcx_ingress\n"991 " | tcx_egress }\n"992 " " HELP_SPEC_OPTIONS " }\n"993 "\n"994 "Note: Only xdp, tcx, tc, netkit, flow_dissector and netfilter attachments\n"995 " are currently supported.\n"996 " For progs attached to cgroups, use \"bpftool cgroup\"\n"997 " to dump program attachments. For program types\n"998 " sk_{filter,skb,msg,reuseport} and lwt/seg6, please\n"999 " consult iproute2.\n"1000 "",1001 bin_name, argv[-2]);1002 1003 return 0;1004}1005 1006static const struct cmd cmds[] = {1007 { "show", do_show },1008 { "list", do_show },1009 { "attach", do_attach },1010 { "detach", do_detach },1011 { "help", do_help },1012 { 0 }1013};1014 1015int do_net(int argc, char **argv)1016{1017 return cmd_select(cmds, argc, argv, do_help);1018}1019