strace/bpf_sock_filter.c
Dmitry V. Levin b93d52fe3d Change the license of strace to LGPL-2.1-or-later
strace is now provided under the terms of the GNU Lesser General
Public License version 2.1 or later, see COPYING for more details.

strace test suite is now provided under the terms of the GNU General
Public License version 2 or later, see tests/COPYING for more details.
2018-12-10 00:00:00 +00:00

55 lines
1.3 KiB
C

/*
* Decoder of socket filter programs.
*
* Copyright (c) 2017 Dmitry V. Levin <ldv@altlinux.org>
* Copyright (c) 2017-2018 The strace developers.
* All rights reserved.
*
* SPDX-License-Identifier: LGPL-2.1-or-later
*/
#include "defs.h"
#include "bpf_filter.h"
#include <linux/filter.h>
#include "xlat/skf_ad.h"
#include "xlat/skf_off.h"
static bool
print_sock_filter_k(const struct bpf_filter_block *const fp)
{
if (BPF_CLASS(fp->code) == BPF_LD && BPF_MODE(fp->code) == BPF_ABS) {
if (fp->k >= (unsigned int) SKF_AD_OFF) {
print_xlat32(SKF_AD_OFF);
tprints("+");
printxval(skf_ad, fp->k - (unsigned int) SKF_AD_OFF,
"SKF_AD_???");
return true;
} else if (fp->k >= (unsigned int) SKF_NET_OFF) {
print_xlat32(SKF_NET_OFF);
tprintf("+%u", fp->k - (unsigned int) SKF_NET_OFF);
return true;
} else if (fp->k >= (unsigned int) SKF_LL_OFF) {
print_xlat32(SKF_LL_OFF);
tprintf("+%u", fp->k - (unsigned int) SKF_LL_OFF);
return true;
}
}
return false;
}
void
print_sock_fprog(struct tcb *const tcp, const kernel_ulong_t addr,
const unsigned short len)
{
print_bpf_fprog(tcp, addr, len, print_sock_filter_k);
}
void
decode_sock_fprog(struct tcb *const tcp, const kernel_ulong_t addr)
{
decode_bpf_fprog(tcp, addr, print_sock_filter_k);
}