linux_dsm_epyc7002/tools/bpf/bpftool/net.c
Yonghong Song f6f3bac08f tools/bpf: bpftool: add net support
Add "bpftool net" support. Networking devices are enumerated
to dump device index/name associated with xdp progs.

For each networking device, tc classes and qdiscs are enumerated
in order to check their bpf filters.
In addition, root handle and clsact ingress/egress are also checked for
bpf filters.  Not all filter information is printed out. Only ifindex,
kind, filter name, prog_id and tag are printed out, which are good
enough to show attachment information. If the filter action
is a bpf action, its bpf program id, bpf name and tag will be
printed out as well.

For example,
  $ ./bpftool net
  xdp [
  ifindex 2 devname eth0 prog_id 198
  ]
  tc_filters [
  ifindex 2 kind qdisc_htb name prefix_matcher.o:[cls_prefix_matcher_htb]
            prog_id 111727 tag d08fe3b4319bc2fd act []
  ifindex 2 kind qdisc_clsact_ingress name fbflow_icmp
            prog_id 130246 tag 3f265c7f26db62c9 act []
  ifindex 2 kind qdisc_clsact_egress name prefix_matcher.o:[cls_prefix_matcher_clsact]
            prog_id 111726 tag 99a197826974c876
  ifindex 2 kind qdisc_clsact_egress name cls_fg_dscp
            prog_id 108619 tag dc4630674fd72dcc act []
  ifindex 2 kind qdisc_clsact_egress name fbflow_egress
            prog_id 130245 tag 72d2d830d6888d2c
  ]
  $ ./bpftool -jp net
  [{
        "xdp": [{
                "ifindex": 2,
                "devname": "eth0",
                "prog_id": 198
            }
        ],
        "tc_filters": [{
                "ifindex": 2,
                "kind": "qdisc_htb",
                "name": "prefix_matcher.o:[cls_prefix_matcher_htb]",
                "prog_id": 111727,
                "tag": "d08fe3b4319bc2fd",
                "act": []
            },{
                "ifindex": 2,
                "kind": "qdisc_clsact_ingress",
                "name": "fbflow_icmp",
                "prog_id": 130246,
                "tag": "3f265c7f26db62c9",
                "act": []
            },{
                "ifindex": 2,
                "kind": "qdisc_clsact_egress",
                "name": "prefix_matcher.o:[cls_prefix_matcher_clsact]",
                "prog_id": 111726,
                "tag": "99a197826974c876"
            },{
                "ifindex": 2,
                "kind": "qdisc_clsact_egress",
                "name": "cls_fg_dscp",
                "prog_id": 108619,
                "tag": "dc4630674fd72dcc",
                "act": []
            },{
                "ifindex": 2,
                "kind": "qdisc_clsact_egress",
                "name": "fbflow_egress",
                "prog_id": 130245,
                "tag": "72d2d830d6888d2c"
            }
        ]
    }
  ]

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-09-06 22:34:08 -07:00

234 lines
5.1 KiB
C

// SPDX-License-Identifier: GPL-2.0+
// Copyright (C) 2018 Facebook
#define _GNU_SOURCE
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <libbpf.h>
#include <net/if.h>
#include <linux/if.h>
#include <linux/rtnetlink.h>
#include <linux/tc_act/tc_bpf.h>
#include <sys/socket.h>
#include <bpf.h>
#include <nlattr.h>
#include "main.h"
#include "netlink_dumper.h"
struct bpf_netdev_t {
int *ifindex_array;
int used_len;
int array_len;
int filter_idx;
};
struct tc_kind_handle {
char kind[64];
int handle;
};
struct bpf_tcinfo_t {
struct tc_kind_handle *handle_array;
int used_len;
int array_len;
bool is_qdisc;
};
static int dump_link_nlmsg(void *cookie, void *msg, struct nlattr **tb)
{
struct bpf_netdev_t *netinfo = cookie;
struct ifinfomsg *ifinfo = msg;
if (netinfo->filter_idx > 0 && netinfo->filter_idx != ifinfo->ifi_index)
return 0;
if (netinfo->used_len == netinfo->array_len) {
netinfo->ifindex_array = realloc(netinfo->ifindex_array,
(netinfo->array_len + 16) * sizeof(int));
netinfo->array_len += 16;
}
netinfo->ifindex_array[netinfo->used_len++] = ifinfo->ifi_index;
return do_xdp_dump(ifinfo, tb);
}
static int dump_class_qdisc_nlmsg(void *cookie, void *msg, struct nlattr **tb)
{
struct bpf_tcinfo_t *tcinfo = cookie;
struct tcmsg *info = msg;
if (tcinfo->is_qdisc) {
/* skip clsact qdisc */
if (tb[TCA_KIND] &&
strcmp(nla_data(tb[TCA_KIND]), "clsact") == 0)
return 0;
if (info->tcm_handle == 0)
return 0;
}
if (tcinfo->used_len == tcinfo->array_len) {
tcinfo->handle_array = realloc(tcinfo->handle_array,
(tcinfo->array_len + 16) * sizeof(struct tc_kind_handle));
tcinfo->array_len += 16;
}
tcinfo->handle_array[tcinfo->used_len].handle = info->tcm_handle;
snprintf(tcinfo->handle_array[tcinfo->used_len].kind,
sizeof(tcinfo->handle_array[tcinfo->used_len].kind),
"%s_%s",
tcinfo->is_qdisc ? "qdisc" : "class",
tb[TCA_KIND] ? nla_getattr_str(tb[TCA_KIND]) : "unknown");
tcinfo->used_len++;
return 0;
}
static int dump_filter_nlmsg(void *cookie, void *msg, struct nlattr **tb)
{
const char *kind = cookie;
return do_filter_dump((struct tcmsg *)msg, tb, kind);
}
static int show_dev_tc_bpf(int sock, unsigned int nl_pid, int ifindex)
{
struct bpf_tcinfo_t tcinfo;
int i, handle, ret;
tcinfo.handle_array = NULL;
tcinfo.used_len = 0;
tcinfo.array_len = 0;
tcinfo.is_qdisc = false;
ret = nl_get_class(sock, nl_pid, ifindex, dump_class_qdisc_nlmsg,
&tcinfo);
if (ret)
return ret;
tcinfo.is_qdisc = true;
ret = nl_get_qdisc(sock, nl_pid, ifindex, dump_class_qdisc_nlmsg,
&tcinfo);
if (ret)
return ret;
for (i = 0; i < tcinfo.used_len; i++) {
ret = nl_get_filter(sock, nl_pid, ifindex,
tcinfo.handle_array[i].handle,
dump_filter_nlmsg,
tcinfo.handle_array[i].kind);
if (ret)
return ret;
}
/* root, ingress and egress handle */
handle = TC_H_ROOT;
ret = nl_get_filter(sock, nl_pid, ifindex, handle, dump_filter_nlmsg,
"root");
if (ret)
return ret;
handle = TC_H_MAKE(TC_H_CLSACT, TC_H_MIN_INGRESS);
ret = nl_get_filter(sock, nl_pid, ifindex, handle, dump_filter_nlmsg,
"qdisc_clsact_ingress");
if (ret)
return ret;
handle = TC_H_MAKE(TC_H_CLSACT, TC_H_MIN_EGRESS);
ret = nl_get_filter(sock, nl_pid, ifindex, handle, dump_filter_nlmsg,
"qdisc_clsact_egress");
if (ret)
return ret;
return 0;
}
static int do_show(int argc, char **argv)
{
int i, sock, ret, filter_idx = -1;
struct bpf_netdev_t dev_array;
unsigned int nl_pid;
char err_buf[256];
if (argc == 2) {
if (strcmp(argv[0], "dev") != 0)
usage();
filter_idx = if_nametoindex(argv[1]);
if (filter_idx == 0) {
fprintf(stderr, "invalid dev name %s\n", argv[1]);
return -1;
}
} else if (argc != 0) {
usage();
}
sock = bpf_netlink_open(&nl_pid);
if (sock < 0) {
fprintf(stderr, "failed to open netlink sock\n");
return -1;
}
dev_array.ifindex_array = NULL;
dev_array.used_len = 0;
dev_array.array_len = 0;
dev_array.filter_idx = filter_idx;
if (json_output)
jsonw_start_array(json_wtr);
NET_START_OBJECT;
NET_START_ARRAY("xdp", "\n");
ret = nl_get_link(sock, nl_pid, dump_link_nlmsg, &dev_array);
NET_END_ARRAY("\n");
if (!ret) {
NET_START_ARRAY("tc_filters", "\n");
for (i = 0; i < dev_array.used_len; i++) {
ret = show_dev_tc_bpf(sock, nl_pid,
dev_array.ifindex_array[i]);
if (ret)
break;
}
NET_END_ARRAY("\n");
}
NET_END_OBJECT;
if (json_output)
jsonw_end_array(json_wtr);
if (ret) {
if (json_output)
jsonw_null(json_wtr);
libbpf_strerror(ret, err_buf, sizeof(err_buf));
fprintf(stderr, "Error: %s\n", err_buf);
}
free(dev_array.ifindex_array);
close(sock);
return ret;
}
static int do_help(int argc, char **argv)
{
if (json_output) {
jsonw_null(json_wtr);
return 0;
}
fprintf(stderr,
"Usage: %s %s { show | list } [dev <devname>]\n"
" %s %s help\n",
bin_name, argv[-2], bin_name, argv[-2]);
return 0;
}
static const struct cmd cmds[] = {
{ "show", do_show },
{ "list", do_show },
{ "help", do_help },
{ 0 }
};
int do_net(int argc, char **argv)
{
return cmd_select(cmds, argc, argv, do_help);
}