Commit 62b64660 authored by Daniel Borkmann's avatar Daniel Borkmann Committed by David S. Miller

bpf: add prog tag test case to bpf selftests

Add the test case used to compare the results from fdinfo with
af_alg's output on the tag. Tests are from min to max sized
programs, with and without maps included.

  # ./test_tag
  test_tag: OK (40945 tests)

Tested on x86_64 and s390x.
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Acked-by: default avatarAlexei Starovoitov <ast@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent d1b662ad
CFLAGS += -Wall -O2 -I../../../../usr/include
test_objs = test_verifier test_maps test_lru_map test_lpm_map
test_objs = test_verifier test_tag test_maps test_lru_map test_lpm_map
TEST_PROGS := test_verifier test_maps test_lru_map test_lpm_map test_kmod.sh
TEST_PROGS := $(test_objs) test_kmod.sh
TEST_FILES := $(test_objs)
all: $(test_objs)
......
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <time.h>
#include <errno.h>
#include <unistd.h>
#include <string.h>
#include <sched.h>
#include <limits.h>
#include <assert.h>
#include <sys/socket.h>
#include <sys/resource.h>
#include <linux/filter.h>
#include <linux/bpf.h>
#include <linux/if_alg.h>
#include "../../../include/linux/filter.h"
#include "bpf_sys.h"
static struct bpf_insn prog[BPF_MAXINSNS];
static void bpf_gen_imm_prog(unsigned int insns, int fd_map)
{
int i;
srand(time(NULL));
for (i = 0; i < insns; i++)
prog[i] = BPF_ALU64_IMM(BPF_MOV, i % BPF_REG_10, rand());
prog[i - 1] = BPF_EXIT_INSN();
}
static void bpf_gen_map_prog(unsigned int insns, int fd_map)
{
int i, j = 0;
for (i = 0; i + 1 < insns; i += 2) {
struct bpf_insn tmp[] = {
BPF_LD_MAP_FD(j++ % BPF_REG_10, fd_map)
};
memcpy(&prog[i], tmp, sizeof(tmp));
}
if (insns % 2 == 0)
prog[insns - 2] = BPF_ALU64_IMM(BPF_MOV, i % BPF_REG_10, 42);
prog[insns - 1] = BPF_EXIT_INSN();
}
static int bpf_try_load_prog(int insns, int fd_map,
void (*bpf_filler)(unsigned int insns,
int fd_map))
{
int fd_prog;
bpf_filler(insns, fd_map);
fd_prog = bpf_prog_load(BPF_PROG_TYPE_SCHED_CLS, prog, insns *
sizeof(struct bpf_insn), "", NULL, 0);
assert(fd_prog > 0);
if (fd_map > 0)
bpf_filler(insns, 0);
return fd_prog;
}
static int __hex2bin(char ch)
{
if ((ch >= '0') && (ch <= '9'))
return ch - '0';
ch = tolower(ch);
if ((ch >= 'a') && (ch <= 'f'))
return ch - 'a' + 10;
return -1;
}
static int hex2bin(uint8_t *dst, const char *src, size_t count)
{
while (count--) {
int hi = __hex2bin(*src++);
int lo = __hex2bin(*src++);
if ((hi < 0) || (lo < 0))
return -1;
*dst++ = (hi << 4) | lo;
}
return 0;
}
static void tag_from_fdinfo(int fd_prog, uint8_t *tag, uint32_t len)
{
const int prefix_len = sizeof("prog_tag:\t") - 1;
char buff[256];
int ret = -1;
FILE *fp;
snprintf(buff, sizeof(buff), "/proc/%d/fdinfo/%d", getpid(),
fd_prog);
fp = fopen(buff, "r");
assert(fp);
while (fgets(buff, sizeof(buff), fp)) {
if (strncmp(buff, "prog_tag:\t", len))
continue;
ret = hex2bin(tag, buff + prefix_len, len);
break;
}
fclose(fp);
assert(!ret);
}
static void tag_from_alg(int insns, uint8_t *tag, uint32_t len)
{
static const struct sockaddr_alg alg = {
.salg_family = AF_ALG,
.salg_type = "hash",
.salg_name = "sha1",
};
int fd_base, fd_alg, ret;
ssize_t size;
fd_base = socket(AF_ALG, SOCK_SEQPACKET, 0);
assert(fd_base > 0);
ret = bind(fd_base, (struct sockaddr *)&alg, sizeof(alg));
assert(!ret);
fd_alg = accept(fd_base, NULL, 0);
assert(fd_alg > 0);
insns *= sizeof(struct bpf_insn);
size = write(fd_alg, prog, insns);
assert(size == insns);
size = read(fd_alg, tag, len);
assert(size == len);
close(fd_alg);
close(fd_base);
}
static void tag_dump(const char *prefix, uint8_t *tag, uint32_t len)
{
int i;
printf("%s", prefix);
for (i = 0; i < len; i++)
printf("%02x", tag[i]);
printf("\n");
}
static void tag_exit_report(int insns, int fd_map, uint8_t *ftag,
uint8_t *atag, uint32_t len)
{
printf("Program tag mismatch for %d insns%s!\n", insns,
fd_map < 0 ? "" : " with map");
tag_dump(" fdinfo result: ", ftag, len);
tag_dump(" af_alg result: ", atag, len);
exit(1);
}
static void do_test(uint32_t *tests, int start_insns, int fd_map,
void (*bpf_filler)(unsigned int insns, int fd))
{
int i, fd_prog;
for (i = start_insns; i <= BPF_MAXINSNS; i++) {
uint8_t ftag[8], atag[sizeof(ftag)];
fd_prog = bpf_try_load_prog(i, fd_map, bpf_filler);
tag_from_fdinfo(fd_prog, ftag, sizeof(ftag));
tag_from_alg(i, atag, sizeof(atag));
if (memcmp(ftag, atag, sizeof(ftag)))
tag_exit_report(i, fd_map, ftag, atag, sizeof(ftag));
close(fd_prog);
sched_yield();
(*tests)++;
}
}
int main(void)
{
struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY };
uint32_t tests = 0;
int i, fd_map;
setrlimit(RLIMIT_MEMLOCK, &rinf);
fd_map = bpf_map_create(BPF_MAP_TYPE_HASH, sizeof(int),
sizeof(int), 1, BPF_F_NO_PREALLOC);
assert(fd_map > 0);
for (i = 0; i < 5; i++) {
do_test(&tests, 2, -1, bpf_gen_imm_prog);
do_test(&tests, 3, fd_map, bpf_gen_map_prog);
}
printf("test_tag: OK (%u tests)\n", tests);
close(fd_map);
return 0;
}
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment