Add a new component and command for bpftool, in order to probe the
system to dump a set of eBPF-related parameters so that users can know
what features are available on the system.
Parameters are dumped in plain or JSON output (with -j/-p options).
The current patch introduces probing of one simple parameter:
availability of the bpf() system call. Later commits
will add other probes.
Sample output:
# bpftool feature probe kernel
Scanning system call availability...
bpf() syscall is available
# bpftool --json --pretty feature probe kernel
{
"syscall_config": {
"have_bpf_syscall": true
}
}
The optional "kernel" keyword enforces probing of the current system,
which is the only possible behaviour at this stage. It can be safely
omitted.
The feature comes with the relevant man page, but bash completion will
come in a dedicated commit.
v3:
- Do not probe kernel version. Contrarily to what is written below for
v2, we can have the kernel version retrieved in libbpf instead of
bpftool (in the patch adding probing for program types).
v2:
- Remove C-style macros output from this patch.
- Even though kernel version is no longer needed for testing kprobes
availability, note that we still collect it in this patch so that
bpftool gets able to probe (in next patches) older kernels as well.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Update references to other bpftool man pages at the bottom of each
manual page. Also reference the "bpf(2)" and "bpf-helpers(7)" man pages.
References are sorted by number of man section, then by
"prog-and-map-go-first", the other pages in alphabetical order.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This is a followup patch for Commit f6f3bac08f
("tools/bpf: bpftool: add net support").
Some improvements are made for the bpftool net output.
Specially, plain output is more concise such that
per attachment should nicely fit in one line.
Compared to previous output, the prog tag is removed
since it can be easily obtained with program id.
Similar to xdp attachments, the device name is added
to tc attachments.
The bpf program attached through shared block
mechanism is supported as well.
$ ip link add dev v1 type veth peer name v2
$ tc qdisc add dev v1 ingress_block 10 egress_block 20 clsact
$ tc qdisc add dev v2 ingress_block 10 egress_block 20 clsact
$ tc filter add block 10 protocol ip prio 25 bpf obj bpf_shared.o sec ingress flowid 1:1
$ tc filter add block 20 protocol ip prio 30 bpf obj bpf_cyclic.o sec classifier flowid 1:1
$ bpftool net
xdp:
tc:
v2(7) clsact/ingress bpf_shared.o:[ingress] id 23
v2(7) clsact/egress bpf_cyclic.o:[classifier] id 24
v1(8) clsact/ingress bpf_shared.o:[ingress] id 23
v1(8) clsact/egress bpf_cyclic.o:[classifier] id 24
The documentation and "bpftool net help" are updated
to make it clear that current implementation only
supports xdp and tc attachments. For programs
attached to cgroups, "bpftool cgroup" can be used
to dump attachments. For other programs e.g.
sk_{filter,skb,msg,reuseport} and lwt/seg6,
iproute2 tools should be used.
The new output:
$ bpftool net
xdp:
eth0(2) driver id 198
tc:
eth0(2) clsact/ingress fbflow_icmp id 335 act [{icmp_action id 336}]
eth0(2) clsact/egress fbflow_egress id 334
$ bpftool -jp net
[{
"xdp": [{
"devname": "eth0",
"ifindex": 2,
"mode": "driver",
"id": 198
}
],
"tc": [{
"devname": "eth0",
"ifindex": 2,
"kind": "clsact/ingress",
"name": "fbflow_icmp",
"id": 335,
"act": [{
"name": "icmp_action",
"id": 336
}
]
},{
"devname": "eth0",
"ifindex": 2,
"kind": "clsact/egress",
"name": "fbflow_egress",
"id": 334
}
]
}
]
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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>