| /* |
| * Decoder of socket filter programs. |
| * |
| * Copyright (c) 2017 Dmitry V. Levin <ldv@altlinux.org> |
| * Copyright (c) 2017-2018 The strace developers. |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. The name of the author may not be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #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); |
| } |