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: NDaniel Borkmann <daniel@iogearbox.net>
Suggested-by: NDavid Beckett <david.beckett@netronome.com>
Signed-off-by: NQuentin Monnet <quentin.monnet@netronome.com>
Acked-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

JSON does not accept hex numbers with 0x prefix.  Simply print
as decimal numbers, JSON should be primarily machine-readable.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NQuentin Monnet <quentin.monnet@netronome.com>
Fixes: 831a0aaf ("tools: bpftool: add JSON output for `bpftool map *` commands")
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Add BPF_MAP_TYPE_CPUMAP map type to the list
of map type recognized by bpftool and define
corresponding text representation.
Signed-off-by: NRoman 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: NQuentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Print the information about device on which map is created.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDaniel 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: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NQuentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: NDaniel 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: 71bb428f ("tools: bpf: add bpftool")
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: NQuentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: NDaniel 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: 831a0aaf ("tools: bpftool: add JSON output for `bpftool map *` commands")
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: NQuentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: NDaniel 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: NPrashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Added support to show filenames of pinned objects.

For example:

root@test# ./bpftool prog
3: tracepoint  name tracepoint__irq  tag f677a7dd722299a3
    loaded_at Oct 26/11:39  uid 0
    xlated 160B  not jited  memlock 4096B  map_ids 4
    pinned /sys/fs/bpf/softirq_prog

4: tracepoint  name tracepoint__irq  tag ea5dc530d00b92b6
    loaded_at Oct 26/11:39  uid 0
    xlated 392B  not jited  memlock 4096B  map_ids 4,6

root@test# ./bpftool --json --pretty prog
[{
        "id": 3,
        "type": "tracepoint",
        "name": "tracepoint__irq",
        "tag": "f677a7dd722299a3",
        "loaded_at": "Oct 26/11:39",
        "uid": 0,
        "bytes_xlated": 160,
        "jited": false,
        "bytes_memlock": 4096,
        "map_ids": [4
        ],
        "pinned": ["/sys/fs/bpf/softirq_prog"
        ]
    },{
        "id": 4,
        "type": "tracepoint",
        "name": "tracepoint__irq",
        "tag": "ea5dc530d00b92b6",
        "loaded_at": "Oct 26/11:39",
        "uid": 0,
        "bytes_xlated": 392,
        "jited": false,
        "bytes_memlock": 4096,
        "map_ids": [4,6
        ],
        "pinned": []
    }
]

root@test# ./bpftool map
4: hash  name start  flags 0x0
    key 4B  value 16B  max_entries 10240  memlock 1003520B
    pinned /sys/fs/bpf/softirq_map1
5: hash  name iptr  flags 0x0
    key 4B  value 8B  max_entries 10240  memlock 921600B

root@test# ./bpftool --json --pretty map
[{
        "id": 4,
        "type": "hash",
        "name": "start",
        "flags": 0,
        "bytes_key": 4,
        "bytes_value": 16,
        "max_entries": 10240,
        "bytes_memlock": 1003520,
        "pinned": ["/sys/fs/bpf/softirq_map1"
        ]
    },{
        "id": 5,
        "type": "hash",
        "name": "iptr",
        "flags": 0,
        "bytes_key": 4,
        "bytes_value": 8,
        "max_entries": 10240,
        "bytes_memlock": 921600,
        "pinned": []
    }
]
Signed-off-by: NPrashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Signed-off-by: NDavid 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: NQuentin Monnet <quentin.monnet@netronome.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid 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: NQuentin Monnet <quentin.monnet@netronome.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid 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: NQuentin Monnet <quentin.monnet@netronome.com>
Acked-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid 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: NQuentin Monnet <quentin.monnet@netronome.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid 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: NQuentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid 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: NQuentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a simple tool for querying and updating BPF objects on the system.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>