tools: bpftool: add "prog run" subcommand to test-run programs

Add a new "bpftool prog run" subcommand to run a loaded program on input
data (and possibly with input context) passed by the user.

Print output data (and output context if relevant) into a file or into
the console. Print return value and duration for the test run into the
console.

A "repeat" argument can be passed to run the program several times in a
row.

The command does not perform any kind of verification based on program
type (Is this program type allowed to use an input context?) or on data
consistency (Can I work with empty input data?), this is left to the
kernel.

Example invocation:

    # perl -e 'print "\x0" x 14' | ./bpftool prog run \
            pinned /sys/fs/bpf/sample_ret0 \
            data_in - data_out - repeat 5
    0000000 0000 0000 0000 0000 0000 0000 0000      | ........ ......
    Return value: 0, duration (average): 260ns

When one of data_in or ctx_in is "-", bpftool reads from standard input,
in binary format. Other formats (JSON, hexdump) might be supported (via
an optional command line keyword like "data_fmt_in") in the future if
relevant, but this would require doing more parsing in bpftool.

v2:
- Fix argument names for function check_single_stdin(). (Yonghong)

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit is contained in:
Quentin Monnet 2019-07-05 18:54:33 +01:00 committed by Daniel Borkmann
parent e232cb6ff7
commit ba95c74524
6 changed files with 485 additions and 3 deletions

View File

@ -29,6 +29,7 @@ PROG COMMANDS
| **bpftool** **prog attach** *PROG* *ATTACH_TYPE* [*MAP*]
| **bpftool** **prog detach** *PROG* *ATTACH_TYPE* [*MAP*]
| **bpftool** **prog tracelog**
| **bpftool** **prog run** *PROG* **data_in** *FILE* [**data_out** *FILE* [**data_size_out** *L*]] [**ctx_in** *FILE* [**ctx_out** *FILE* [**ctx_size_out** *M*]]] [**repeat** *N*]
| **bpftool** **prog help**
|
| *MAP* := { **id** *MAP_ID* | **pinned** *FILE* }
@ -146,6 +147,39 @@ DESCRIPTION
streaming data from BPF programs to user space, one can use
perf events (see also **bpftool-map**\ (8)).
**bpftool prog run** *PROG* **data_in** *FILE* [**data_out** *FILE* [**data_size_out** *L*]] [**ctx_in** *FILE* [**ctx_out** *FILE* [**ctx_size_out** *M*]]] [**repeat** *N*]
Run BPF program *PROG* in the kernel testing infrastructure
for BPF, meaning that the program works on the data and
context provided by the user, and not on actual packets or
monitored functions etc. Return value and duration for the
test run are printed out to the console.
Input data is read from the *FILE* passed with **data_in**.
If this *FILE* is "**-**", input data is read from standard
input. Input context, if any, is read from *FILE* passed with
**ctx_in**. Again, "**-**" can be used to read from standard
input, but only if standard input is not already in use for
input data. If a *FILE* is passed with **data_out**, output
data is written to that file. Similarly, output context is
written to the *FILE* passed with **ctx_out**. For both
output flows, "**-**" can be used to print to the standard
output (as plain text, or JSON if relevant option was
passed). If output keywords are omitted, output data and
context are discarded. Keywords **data_size_out** and
**ctx_size_out** are used to pass the size (in bytes) for the
output buffers to the kernel, although the default of 32 kB
should be more than enough for most cases.
Keyword **repeat** is used to indicate the number of
consecutive runs to perform. Note that output data and
context printed to files correspond to the last of those
runs. The duration printed out at the end of the runs is an
average over all runs performed by the command.
Not all program types support test run. Among those which do,
not all of them can take the **ctx_in**/**ctx_out**
arguments. bpftool does not perform checks on program types.
**bpftool prog help**
Print short help message.

View File

@ -408,10 +408,34 @@ _bpftool()
tracelog)
return 0
;;
run)
if [[ ${#words[@]} -lt 5 ]]; then
_filedir
return 0
fi
case $prev in
id)
_bpftool_get_prog_ids
return 0
;;
data_in|data_out|ctx_in|ctx_out)
_filedir
return 0
;;
repeat|data_size_out|ctx_size_out)
return 0
;;
*)
_bpftool_once_attr 'data_in data_out data_size_out \
ctx_in ctx_out ctx_size_out repeat'
return 0
;;
esac
;;
*)
[[ $prev == $object ]] && \
COMPREPLY=( $( compgen -W 'dump help pin attach detach load \
show list tracelog' -- "$cur" ) )
COMPREPLY=( $( compgen -W 'dump help pin attach detach \
load show list tracelog run' -- "$cur" ) )
;;
esac
;;

View File

@ -117,6 +117,35 @@ bool is_prefix(const char *pfx, const char *str)
return !memcmp(str, pfx, strlen(pfx));
}
/* Last argument MUST be NULL pointer */
int detect_common_prefix(const char *arg, ...)
{
unsigned int count = 0;
const char *ref;
char msg[256];
va_list ap;
snprintf(msg, sizeof(msg), "ambiguous prefix: '%s' could be '", arg);
va_start(ap, arg);
while ((ref = va_arg(ap, const char *))) {
if (!is_prefix(arg, ref))
continue;
count++;
if (count > 1)
strncat(msg, "' or '", sizeof(msg) - strlen(msg) - 1);
strncat(msg, ref, sizeof(msg) - strlen(msg) - 1);
}
va_end(ap);
strncat(msg, "'", sizeof(msg) - strlen(msg) - 1);
if (count >= 2) {
p_err(msg);
return -1;
}
return 0;
}
void fprint_hex(FILE *f, void *arg, unsigned int n, const char *sep)
{
unsigned char *data = arg;

View File

@ -101,6 +101,7 @@ void p_err(const char *fmt, ...);
void p_info(const char *fmt, ...);
bool is_prefix(const char *pfx, const char *str);
int detect_common_prefix(const char *arg, ...);
void fprint_hex(FILE *f, void *arg, unsigned int n, const char *sep);
void usage(void) __noreturn;

View File

@ -15,6 +15,7 @@
#include <sys/stat.h>
#include <linux/err.h>
#include <linux/sizes.h>
#include <bpf.h>
#include <btf.h>
@ -748,6 +749,344 @@ static int do_detach(int argc, char **argv)
return 0;
}
static int check_single_stdin(char *file_data_in, char *file_ctx_in)
{
if (file_data_in && file_ctx_in &&
!strcmp(file_data_in, "-") && !strcmp(file_ctx_in, "-")) {
p_err("cannot use standard input for both data_in and ctx_in");
return -1;
}
return 0;
}
static int get_run_data(const char *fname, void **data_ptr, unsigned int *size)
{
size_t block_size = 256;
size_t buf_size = block_size;
size_t nb_read = 0;
void *tmp;
FILE *f;
if (!fname) {
*data_ptr = NULL;
*size = 0;
return 0;
}
if (!strcmp(fname, "-"))
f = stdin;
else
f = fopen(fname, "r");
if (!f) {
p_err("failed to open %s: %s", fname, strerror(errno));
return -1;
}
*data_ptr = malloc(block_size);
if (!*data_ptr) {
p_err("failed to allocate memory for data_in/ctx_in: %s",
strerror(errno));
goto err_fclose;
}
while ((nb_read += fread(*data_ptr + nb_read, 1, block_size, f))) {
if (feof(f))
break;
if (ferror(f)) {
p_err("failed to read data_in/ctx_in from %s: %s",
fname, strerror(errno));
goto err_free;
}
if (nb_read > buf_size - block_size) {
if (buf_size == UINT32_MAX) {
p_err("data_in/ctx_in is too long (max: %d)",
UINT32_MAX);
goto err_free;
}
/* No space for fread()-ing next chunk; realloc() */
buf_size *= 2;
tmp = realloc(*data_ptr, buf_size);
if (!tmp) {
p_err("failed to reallocate data_in/ctx_in: %s",
strerror(errno));
goto err_free;
}
*data_ptr = tmp;
}
}
if (f != stdin)
fclose(f);
*size = nb_read;
return 0;
err_free:
free(*data_ptr);
*data_ptr = NULL;
err_fclose:
if (f != stdin)
fclose(f);
return -1;
}
static void hex_print(void *data, unsigned int size, FILE *f)
{
size_t i, j;
char c;
for (i = 0; i < size; i += 16) {
/* Row offset */
fprintf(f, "%07zx\t", i);
/* Hexadecimal values */
for (j = i; j < i + 16 && j < size; j++)
fprintf(f, "%02x%s", *(uint8_t *)(data + j),
j % 2 ? " " : "");
for (; j < i + 16; j++)
fprintf(f, " %s", j % 2 ? " " : "");
/* ASCII values (if relevant), '.' otherwise */
fprintf(f, "| ");
for (j = i; j < i + 16 && j < size; j++) {
c = *(char *)(data + j);
if (c < ' ' || c > '~')
c = '.';
fprintf(f, "%c%s", c, j == i + 7 ? " " : "");
}
fprintf(f, "\n");
}
}
static int
print_run_output(void *data, unsigned int size, const char *fname,
const char *json_key)
{
size_t nb_written;
FILE *f;
if (!fname)
return 0;
if (!strcmp(fname, "-")) {
f = stdout;
if (json_output) {
jsonw_name(json_wtr, json_key);
print_data_json(data, size);
} else {
hex_print(data, size, f);
}
return 0;
}
f = fopen(fname, "w");
if (!f) {
p_err("failed to open %s: %s", fname, strerror(errno));
return -1;
}
nb_written = fwrite(data, 1, size, f);
fclose(f);
if (nb_written != size) {
p_err("failed to write output data/ctx: %s", strerror(errno));
return -1;
}
return 0;
}
static int alloc_run_data(void **data_ptr, unsigned int size_out)
{
*data_ptr = calloc(size_out, 1);
if (!*data_ptr) {
p_err("failed to allocate memory for output data/ctx: %s",
strerror(errno));
return -1;
}
return 0;
}
static int do_run(int argc, char **argv)
{
char *data_fname_in = NULL, *data_fname_out = NULL;
char *ctx_fname_in = NULL, *ctx_fname_out = NULL;
struct bpf_prog_test_run_attr test_attr = {0};
const unsigned int default_size = SZ_32K;
void *data_in = NULL, *data_out = NULL;
void *ctx_in = NULL, *ctx_out = NULL;
unsigned int repeat = 1;
int fd, err;
if (!REQ_ARGS(4))
return -1;
fd = prog_parse_fd(&argc, &argv);
if (fd < 0)
return -1;
while (argc) {
if (detect_common_prefix(*argv, "data_in", "data_out",
"data_size_out", NULL))
return -1;
if (detect_common_prefix(*argv, "ctx_in", "ctx_out",
"ctx_size_out", NULL))
return -1;
if (is_prefix(*argv, "data_in")) {
NEXT_ARG();
if (!REQ_ARGS(1))
return -1;
data_fname_in = GET_ARG();
if (check_single_stdin(data_fname_in, ctx_fname_in))
return -1;
} else if (is_prefix(*argv, "data_out")) {
NEXT_ARG();
if (!REQ_ARGS(1))
return -1;
data_fname_out = GET_ARG();
} else if (is_prefix(*argv, "data_size_out")) {
char *endptr;
NEXT_ARG();
if (!REQ_ARGS(1))
return -1;
test_attr.data_size_out = strtoul(*argv, &endptr, 0);
if (*endptr) {
p_err("can't parse %s as output data size",
*argv);
return -1;
}
NEXT_ARG();
} else if (is_prefix(*argv, "ctx_in")) {
NEXT_ARG();
if (!REQ_ARGS(1))
return -1;
ctx_fname_in = GET_ARG();
if (check_single_stdin(data_fname_in, ctx_fname_in))
return -1;
} else if (is_prefix(*argv, "ctx_out")) {
NEXT_ARG();
if (!REQ_ARGS(1))
return -1;
ctx_fname_out = GET_ARG();
} else if (is_prefix(*argv, "ctx_size_out")) {
char *endptr;
NEXT_ARG();
if (!REQ_ARGS(1))
return -1;
test_attr.ctx_size_out = strtoul(*argv, &endptr, 0);
if (*endptr) {
p_err("can't parse %s as output context size",
*argv);
return -1;
}
NEXT_ARG();
} else if (is_prefix(*argv, "repeat")) {
char *endptr;
NEXT_ARG();
if (!REQ_ARGS(1))
return -1;
repeat = strtoul(*argv, &endptr, 0);
if (*endptr) {
p_err("can't parse %s as repeat number",
*argv);
return -1;
}
NEXT_ARG();
} else {
p_err("expected no more arguments, 'data_in', 'data_out', 'data_size_out', 'ctx_in', 'ctx_out', 'ctx_size_out' or 'repeat', got: '%s'?",
*argv);
return -1;
}
}
err = get_run_data(data_fname_in, &data_in, &test_attr.data_size_in);
if (err)
return -1;
if (data_in) {
if (!test_attr.data_size_out)
test_attr.data_size_out = default_size;
err = alloc_run_data(&data_out, test_attr.data_size_out);
if (err)
goto free_data_in;
}
err = get_run_data(ctx_fname_in, &ctx_in, &test_attr.ctx_size_in);
if (err)
goto free_data_out;
if (ctx_in) {
if (!test_attr.ctx_size_out)
test_attr.ctx_size_out = default_size;
err = alloc_run_data(&ctx_out, test_attr.ctx_size_out);
if (err)
goto free_ctx_in;
}
test_attr.prog_fd = fd;
test_attr.repeat = repeat;
test_attr.data_in = data_in;
test_attr.data_out = data_out;
test_attr.ctx_in = ctx_in;
test_attr.ctx_out = ctx_out;
err = bpf_prog_test_run_xattr(&test_attr);
if (err) {
p_err("failed to run program: %s", strerror(errno));
goto free_ctx_out;
}
err = 0;
if (json_output)
jsonw_start_object(json_wtr); /* root */
/* Do not exit on errors occurring when printing output data/context,
* we still want to print return value and duration for program run.
*/
if (test_attr.data_size_out)
err += print_run_output(test_attr.data_out,
test_attr.data_size_out,
data_fname_out, "data_out");
if (test_attr.ctx_size_out)
err += print_run_output(test_attr.ctx_out,
test_attr.ctx_size_out,
ctx_fname_out, "ctx_out");
if (json_output) {
jsonw_uint_field(json_wtr, "retval", test_attr.retval);
jsonw_uint_field(json_wtr, "duration", test_attr.duration);
jsonw_end_object(json_wtr); /* root */
} else {
fprintf(stdout, "Return value: %u, duration%s: %uns\n",
test_attr.retval,
repeat > 1 ? " (average)" : "", test_attr.duration);
}
free_ctx_out:
free(ctx_out);
free_ctx_in:
free(ctx_in);
free_data_out:
free(data_out);
free_data_in:
free(data_in);
return err;
}
static int load_with_options(int argc, char **argv, bool first_prog_only)
{
struct bpf_object_load_attr load_attr = { 0 };
@ -1058,6 +1397,11 @@ static int do_help(int argc, char **argv)
" [pinmaps MAP_DIR]\n"
" %s %s attach PROG ATTACH_TYPE [MAP]\n"
" %s %s detach PROG ATTACH_TYPE [MAP]\n"
" %s %s run PROG \\\n"
" data_in FILE \\\n"
" [data_out FILE [data_size_out L]] \\\n"
" [ctx_in FILE [ctx_out FILE [ctx_size_out M]]] \\\n"
" [repeat N]\n"
" %s %s tracelog\n"
" %s %s help\n"
"\n"
@ -1079,7 +1423,8 @@ static int do_help(int argc, char **argv)
"",
bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2],
bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2],
bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2]);
bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2],
bin_name, argv[-2]);
return 0;
}
@ -1095,6 +1440,7 @@ static const struct cmd cmds[] = {
{ "attach", do_attach },
{ "detach", do_detach },
{ "tracelog", do_tracelog },
{ "run", do_run },
{ 0 }
};

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@ -0,0 +1,48 @@
/* SPDX-License-Identifier: GPL-2.0-only */
/*
* include/linux/sizes.h
*/
#ifndef __LINUX_SIZES_H__
#define __LINUX_SIZES_H__
#include <linux/const.h>
#define SZ_1 0x00000001
#define SZ_2 0x00000002
#define SZ_4 0x00000004
#define SZ_8 0x00000008
#define SZ_16 0x00000010
#define SZ_32 0x00000020
#define SZ_64 0x00000040
#define SZ_128 0x00000080
#define SZ_256 0x00000100
#define SZ_512 0x00000200
#define SZ_1K 0x00000400
#define SZ_2K 0x00000800
#define SZ_4K 0x00001000
#define SZ_8K 0x00002000
#define SZ_16K 0x00004000
#define SZ_32K 0x00008000
#define SZ_64K 0x00010000
#define SZ_128K 0x00020000
#define SZ_256K 0x00040000
#define SZ_512K 0x00080000
#define SZ_1M 0x00100000
#define SZ_2M 0x00200000
#define SZ_4M 0x00400000
#define SZ_8M 0x00800000
#define SZ_16M 0x01000000
#define SZ_32M 0x02000000
#define SZ_64M 0x04000000
#define SZ_128M 0x08000000
#define SZ_256M 0x10000000
#define SZ_512M 0x20000000
#define SZ_1G 0x40000000
#define SZ_2G 0x80000000
#define SZ_4G _AC(0x100000000, ULL)
#endif /* __LINUX_SIZES_H__ */