diff options
Diffstat (limited to 'tools/bpf/bpftool/net.c')
| -rw-r--r-- | tools/bpf/bpftool/net.c | 275 |
1 files changed, 275 insertions, 0 deletions
diff --git a/tools/bpf/bpftool/net.c b/tools/bpf/bpftool/net.c new file mode 100644 index 000000000000..d441bb7035ca --- /dev/null +++ b/tools/bpf/bpftool/net.c @@ -0,0 +1,275 @@ +// SPDX-License-Identifier: GPL-2.0+ +// Copyright (C) 2018 Facebook + +#define _GNU_SOURCE +#include <errno.h> +#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 ip_devname_ifindex { + char devname[64]; + int ifindex; +}; + +struct bpf_netdev_t { + struct ip_devname_ifindex *devices; + 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; +}; + +struct bpf_filter_t { + const char *kind; + const char *devname; + int ifindex; +}; + +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->devices = realloc(netinfo->devices, + (netinfo->array_len + 16) * + sizeof(struct ip_devname_ifindex)); + if (!netinfo->devices) + return -ENOMEM; + + netinfo->array_len += 16; + } + netinfo->devices[netinfo->used_len].ifindex = ifinfo->ifi_index; + snprintf(netinfo->devices[netinfo->used_len].devname, + sizeof(netinfo->devices[netinfo->used_len].devname), + "%s", + tb[IFLA_IFNAME] + ? libbpf_nla_getattr_str(tb[IFLA_IFNAME]) + : ""); + netinfo->used_len++; + + 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(libbpf_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)); + if (!tcinfo->handle_array) + return -ENOMEM; + + 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", + tb[TCA_KIND] + ? libbpf_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 struct bpf_filter_t *filter_info = cookie; + + return do_filter_dump((struct tcmsg *)msg, tb, filter_info->kind, + filter_info->devname, filter_info->ifindex); +} + +static int show_dev_tc_bpf(int sock, unsigned int nl_pid, + struct ip_devname_ifindex *dev) +{ + struct bpf_filter_t filter_info; + struct bpf_tcinfo_t tcinfo; + int i, handle, ret = 0; + + tcinfo.handle_array = NULL; + tcinfo.used_len = 0; + tcinfo.array_len = 0; + + tcinfo.is_qdisc = false; + ret = libbpf_nl_get_class(sock, nl_pid, dev->ifindex, + dump_class_qdisc_nlmsg, &tcinfo); + if (ret) + goto out; + + tcinfo.is_qdisc = true; + ret = libbpf_nl_get_qdisc(sock, nl_pid, dev->ifindex, + dump_class_qdisc_nlmsg, &tcinfo); + if (ret) + goto out; + + filter_info.devname = dev->devname; + filter_info.ifindex = dev->ifindex; + for (i = 0; i < tcinfo.used_len; i++) { + filter_info.kind = tcinfo.handle_array[i].kind; + ret = libbpf_nl_get_filter(sock, nl_pid, dev->ifindex, + tcinfo.handle_array[i].handle, + dump_filter_nlmsg, &filter_info); + if (ret) + goto out; + } + + /* root, ingress and egress handle */ + handle = TC_H_ROOT; + filter_info.kind = "root"; + ret = libbpf_nl_get_filter(sock, nl_pid, dev->ifindex, handle, + dump_filter_nlmsg, &filter_info); + if (ret) + goto out; + + handle = TC_H_MAKE(TC_H_CLSACT, TC_H_MIN_INGRESS); + filter_info.kind = "clsact/ingress"; + ret = libbpf_nl_get_filter(sock, nl_pid, dev->ifindex, handle, + dump_filter_nlmsg, &filter_info); + if (ret) + goto out; + + handle = TC_H_MAKE(TC_H_CLSACT, TC_H_MIN_EGRESS); + filter_info.kind = "clsact/egress"; + ret = libbpf_nl_get_filter(sock, nl_pid, dev->ifindex, handle, + dump_filter_nlmsg, &filter_info); + if (ret) + goto out; + +out: + free(tcinfo.handle_array); + 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 = libbpf_netlink_open(&nl_pid); + if (sock < 0) { + fprintf(stderr, "failed to open netlink sock\n"); + return -1; + } + + dev_array.devices = 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", "%s:\n"); + ret = libbpf_nl_get_link(sock, nl_pid, dump_link_nlmsg, &dev_array); + NET_END_ARRAY("\n"); + + if (!ret) { + NET_START_ARRAY("tc", "%s:\n"); + for (i = 0; i < dev_array.used_len; i++) { + ret = show_dev_tc_bpf(sock, nl_pid, + &dev_array.devices[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.devices); + 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" + "Note: Only xdp and tc attachments are supported now.\n" + " For progs attached to cgroups, use \"bpftool cgroup\"\n" + " to dump program attachments. For program types\n" + " sk_{filter,skb,msg,reuseport} and lwt/seg6, please\n" + " consult iproute2.\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); +} |