bpftool output is not user friendly when dumping a map with only a few
populated entries:
$ bpftool map
1: devmap name tx_devmap flags 0x0
key 4B value 4B max_entries 64 memlock 4096B
2: array name tx_idxmap flags 0x0
key 4B value 4B max_entries 64 memlock 4096B
$ bpftool map dump id 1
key:
00 00 00 00
value:
No such file or directory
key:
01 00 00 00
value:
No such file or directory
key:
02 00 00 00
value:
No such file or directory
key: 03 00 00 00 value: 03 00 00 00
Handle ENOENT by keeping the line format sane and dumping
"<no entry>" for the value
$ bpftool map dump id 1
key: 00 00 00 00 value: <no entry>
key: 01 00 00 00 value: <no entry>
key: 02 00 00 00 value: <no entry>
key: 03 00 00 00 value: 03 00 00 00
...
Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The limit for memory locked in the kernel by a process is usually set to
64 kbytes by default. This can be an issue when creating large BPF maps
and/or loading many programs. A workaround is to raise this limit for
the current process before trying to create a new BPF map. Changing the
hard limit requires the CAP_SYS_RESOURCE and can usually only be done by
root user (for non-root users, a call to setrlimit fails (and sets
errno) and the program simply goes on with its rlimit unchanged).
There is no API to get the current amount of memory locked for a user,
therefore we cannot raise the limit only when required. One solution,
used by bcc, is to try to create the map, and on getting a EPERM error,
raising the limit to infinity before giving another try. Another
approach, used in iproute2, is to raise the limit in all cases, before
trying to create the map.
Here we do the same as in iproute2: the rlimit is raised to infinity
before trying to load programs or to create maps with bpftool.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Add a way of creating maps from user space. The command takes
as parameters most of the attributes of the map creation system
call command. After map is created its pinned to bpffs. This makes
it possible to easily and dynamically (without rebuilding programs)
test various corner cases related to map creation.
Map type names are taken from bpftool's array used for printing.
In general these days we try to make use of libbpf type names, but
there are no map type names in libbpf as of today.
As with most features I add the motivation is testing (offloads) :)
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Since map lookup error can be ENOENT or EOPNOTSUPP, let's print
strerror() as error message in normal and JSON output.
This patch adds helper function print_entry_error() to print
entry from lookup error occurs
Example: Following example dumps a map which does not support lookup.
Output before:
root# bpftool map -jp dump id 40
[
"key": ["0x0a","0x00","0x00","0x00"
],
"value": {
"error": "can\'t lookup element"
},
"key": ["0x0b","0x00","0x00","0x00"
],
"value": {
"error": "can\'t lookup element"
}
]
root# bpftool map dump id 40
can't lookup element with key:
0a 00 00 00
can't lookup element with key:
0b 00 00 00
Found 0 elements
Output after changes:
root# bpftool map dump -jp id 45
[
"key": ["0x0a","0x00","0x00","0x00"
],
"value": {
"error": "Operation not supported"
},
"key": ["0x0b","0x00","0x00","0x00"
],
"value": {
"error": "Operation not supported"
}
]
root# bpftool map dump id 45
key:
0a 00 00 00
value:
Operation not supported
key:
0b 00 00 00
value:
Operation not supported
Found 0 elements
Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
do_dump() function in bpftool/map.c has deep indentations. In order
to reduce deep indent, let's move element printing code out of
do_dump() into dump_map_elem() function.
Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit adds support for BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE
map type.
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Add BPF_MAP_TYPE_REUSEPORT_SOCKARRAY map type to the list
of maps types which bpftool recognizes.
Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: Yonghong Song <yhs@fb.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Currently, prog array map and map of maps are not supported
in bpftool. This patch added the support.
Different from other map types, for prog array map and
map of maps, the key returned bpf_get_next_key() may not
point to a valid value. So for these two map types,
no error will be printed out when such a scenario happens.
The following is the plain and json dump if btf is not available:
$ ./bpftool map dump id 10
key: 08 00 00 00 value: 5c 01 00 00
Found 1 element
$ ./bpftool -jp map dump id 10
[{
"key": ["0x08","0x00","0x00","0x00"
],
"value": ["0x5c","0x01","0x00","0x00"
]
}]
If the BTF is available, the dump looks below:
$ ./bpftool map dump id 2
[{
"key": 0,
"value": 7
}
]
$ ./bpftool -jp map dump id 2
[{
"key": ["0x00","0x00","0x00","0x00"
],
"value": ["0x07","0x00","0x00","0x00"
],
"formatted": {
"key": 0,
"value": 7
}
}]
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
When listed all maps, bpftool currently shows (null) for xskmap.
Added xskmap type in map_type_name[] to show correct type.
Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Daniel Borkmann says:
====================
pull-request: bpf-next 2018-08-07
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Add cgroup local storage for BPF programs, which provides a fast
accessible memory for storing various per-cgroup data like number
of transmitted packets, etc, from Roman.
2) Support bpf_get_socket_cookie() BPF helper in several more program
types that have a full socket available, from Andrey.
3) Significantly improve the performance of perf events which are
reported from BPF offload. Also convert a couple of BPF AF_XDP
samples overto use libbpf, both from Jakub.
4) seg6local LWT provides the End.DT6 action, which allows to
decapsulate an outer IPv6 header containing a Segment Routing Header.
Adds this action now to the seg6local BPF interface, from Mathieu.
5) Do not mark dst register as unbounded in MOV64 instruction when
both src and dst register are the same, from Arthur.
6) Define u_smp_rmb() and u_smp_wmb() to their respective barrier
instructions on arm64 for the AF_XDP sample code, from Brian.
7) Convert the tcp_client.py and tcp_server.py BPF selftest scripts
over from Python 2 to Python 3, from Jeremy.
8) Enable BTF build flags to the BPF sample code Makefile, from Taeung.
9) Remove an unnecessary rcu_read_lock() in run_lwt_bpf(), from Taehee.
10) Several improvements to the README.rst from the BPF documentation
to make it more consistent with RST format, from Tobin.
11) Replace all occurrences of strerror() by calls to strerror_r()
in libbpf and fix a FORTIFY_SOURCE build error along with it,
from Thomas.
12) Fix a bug in bpftool's get_btf() function to correctly propagate
an error via PTR_ERR(), from Yue.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Add BPF_MAP_TYPE_CGROUP_STORAGE maps to the list
of maps types which bpftool recognizes.
Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
I hit the following problem when I tried to use bpftool
to dump a percpu array.
$ sudo ./bpftool map show
61: percpu_array name stub flags 0x0
key 4B value 4B max_entries 1 memlock 4096B
...
$ sudo ./bpftool map dump id 61
bpftool: malloc.c:2406: sysmalloc: Assertion
`(old_top == initial_top (av) && old_size == 0) || \
((unsigned long) (old_size) >= MINSIZE && \
prev_inuse (old_top) && \
((unsigned long) old_end & (pagesize - 1)) == 0)'
failed.
Aborted
Further debugging revealed that this is due to
miscommunication between bpftool and kernel.
For example, for the above percpu_array with value size of 4B.
The map info returned to user space has value size of 4B.
In bpftool, the values array for lookup is allocated like:
info->value_size * get_possible_cpus() = 4 * get_possible_cpus()
In kernel (kernel/bpf/syscall.c), the values array size is
rounded up to multiple of 8.
round_up(map->value_size, 8) * num_possible_cpus()
= 8 * num_possible_cpus()
So when kernel copies the values to user buffer, the kernel will
overwrite beyond user buffer boundary.
This patch fixed the issue by allocating and stepping through
percpu map value array properly in bpftool.
Fixes: 71bb428fe2 ("tools: bpf: add bpftool")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Fix inconsistent IS_ERR and PTR_ERR in get_btf,
the proper pointer to be passed as argument is '*btf'
This issue was detected with the help of Coccinelle.
Fixes: 2d3feca8c4 ("bpf: btf: print map dump and lookup with btf info")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This patch augments the output of bpftool's map dump and map lookup
commands to print data along side btf info, if the correspondin btf
info is available. The outputs for each of map dump and map lookup
commands are augmented in two ways:
1. when neither of -j and -p are supplied, btf-ful map data is printed
whose aim is human readability. This means no commitments for json- or
backward- compatibility.
2. when either -j or -p are supplied, a new json object named
"formatted" is added for each key-value pair. This object contains the
same data as the key-value pair, but with btf info. "formatted" object
promises json- and backward- compatibility. Below is a sample output.
$ bpftool map dump -p id 8
[{
"key": ["0x0f","0x00","0x00","0x00"
],
"value": ["0x03", "0x00", "0x00", "0x00", ...
],
"formatted": {
"key": 15,
"value": {
"int_field": 3,
...
}
}
}
]
This patch calls btf_dumper introduced in previous patch to accomplish
the above. Indeed, btf-ful info is only displayed if btf data for the
given map is available. Otherwise existing output is displayed as-is.
Signed-off-by: Okash Khawaja <osk@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Add map parameter to prog load which will allow reuse of existing
maps instead of creating new ones.
We need feature detection and compat code for reallocarray, since
it's not available in many libc versions.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Drop my author comments, those are from the early days of
bpftool and make little sense in tree, where we have quite
a few people contributing and git to attribute the work.
While at it bump some copyrights.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This adds the SOCKHASH map type to bpftools so that we get correct
pretty printing.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Users of BPF sooner or later discover perf_event_output() helpers
and BPF_MAP_TYPE_PERF_EVENT_ARRAY. Dumping this array type is
not possible, however, we can add simple reading of perf events.
Create a new event_pipe subcommand for maps, this sub command
will only work with BPF_MAP_TYPE_PERF_EVENT_ARRAY maps.
Parts of the code from samples/bpf/trace_output_user.c.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Move the get_possible_cpus() function to shared code. No functional
changes.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Instead of spelling [hex] BYTES everywhere use DATA as keyword
for generalized value. This will help us keep the messages
concise when longer command are added in the future. It will
also be useful once BTF support comes. We will only have to
change the definition of DATA.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
bpftool uses hexadecimal values when it dumps map contents:
# bpftool map dump id 1337
key: ff 13 37 ff value: a1 b2 c3 d4 ff ff ff ff
Found 1 element
In order to lookup or update values with bpftool, the natural reflex is
then to copy and paste the values to the command line, and to try to run
something like:
# bpftool map update id 1337 key ff 13 37 ff \
value 00 00 00 00 00 00 1a 2b
Error: error parsing byte: ff
bpftool complains, because it uses strtoul() with a 0 base to parse the
bytes, and that without a "0x" prefix, the bytes are considered as
decimal values (or even octal if they start with "0").
To feed hexadecimal values instead, one needs to add "0x" prefixes
everywhere necessary:
# bpftool map update id 1337 key 0xff 0x13 0x37 0xff \
value 0 0 0 0 0 0 0x1a 0x2b
To make it easier to use hexadecimal values, add an optional "hex"
keyword to put after "key" or "value" to tell bpftool to consider the
digits as hexadecimal. We can now do:
# bpftool map update id 1337 key hex ff 13 37 ff \
value hex 0 0 0 0 0 0 1a 2b
Without the "hex" keyword, the bytes are still parsed according to
normal integer notation (decimal if no prefix, or hexadecimal or octal
if "0x" or "0" prefix is used, respectively).
The patch also add related documentation and bash completion for the
"hex" keyword.
Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Suggested-by: David Beckett <david.beckett@netronome.com>
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Add BPF_MAP_TYPE_CPUMAP map type to the list
of map type recognized by bpftool and define
corresponding text representation.
Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Quentin Monnet <quentin.monnet@netronome.com>
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Acked-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Print the information about device on which map is created.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
iproute2 seems to accept show and list as aliases.
Let's do the same thing, and by allowing both bring
cgroup syntax back in line with maps and progs.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
On program/map show we may get an ID of an object from GETNEXT,
but the object may disappear before we call GET_FD_BY_ID. If
that happens, ignore the object and continue.
Fixes: 71bb428fe2 ("tools: bpf: add bpftool")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
We can't return from the middle of do_show(), because
json_array will not be closed. Break out of the loop.
Note that the error handling after the loop depends on
errno, so no need to set err.
Fixes: 831a0aafe5 ("tools: bpftool: add JSON output for `bpftool map *` commands")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Making it optional to show file names of pinned objects because
it scans complete bpf-fs filesystem which is costly.
Added option -f|--bpffs. Documentation updated.
Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
Update the documentation to provide help about JSON output generation,
and add an example in bpftool-prog manual page.
Also reintroduce an example that was left aside when the tool was moved
from GitHub to the kernel sources, in order to show how to mount the
bpffs file system (to pin programs) inside the bpftool-prog manual page.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
As all commands can now return JSON output (possibly just a "null"
value), output of `bpftool --json batch file FILE` should also be fully
JSON compliant.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Turn err() and info() macros into functions.
In order to avoid naming conflicts with variables in the code, rename
them as p_err() and p_info() respectively.
The behavior of these functions is similar to the one of the macros for
plain output. However, when JSON output is requested, these macros
return a JSON-formatted "error" object instead of printing a message to
stderr.
To handle error messages correctly with JSON, a modification was brought
to their behavior nonetheless: the functions now append a end-of-line
character at the end of the message. This way, we can remove end-of-line
characters at the end of the argument strings, and not have them in the
JSON output.
All error messages are formatted to hold in a single call to p_err(), in
order to produce a single JSON field.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reuse the json_writer API introduced in an earlier commit to make
bpftool able to generate JSON output on
`bpftool map { show | dump | lookup | getnext }` commands. Remaining
commands produce no output.
Some functions have been spit into plain-output and JSON versions in
order to remain readable.
Outputs for sample maps have been successfully tested against a JSON
validator.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make error messages more consistent. Specifically, when bpftool fails at
parsing map key bytes, make it print a single error message to stderr
and return from the function, instead of (always) printing a second
error message afterwards.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make print_hex() able to print to any file instead of standard output
only, and rename it to fprint_hex(). The function can now be called with
the info() macro, for example, without splitting the output between
standard and error outputs.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a simple tool for querying and updating BPF objects on the system.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
David Ahern