2 * Decoder of socket filter programs.
4 * Copyright (c) 2017 Dmitry V. Levin <ldv@altlinux.org>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. The name of the author may not be used to endorse or promote products
16 * derived from this software without specific prior written permission.
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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32 #include "bpf_filter.h"
34 #include <linux/filter.h>
35 #include "xlat/skf_ad.h"
36 #include "xlat/skf_off.h"
39 print_sock_filter_k(const struct bpf_filter_block *const fp)
41 if (BPF_CLASS(fp->code) == BPF_LD && BPF_MODE(fp->code) == BPF_ABS) {
42 if (fp->k >= (unsigned int) SKF_AD_OFF) {
43 print_xlat32(SKF_AD_OFF);
45 printxval(skf_ad, fp->k - (unsigned int) SKF_AD_OFF,
48 } else if (fp->k >= (unsigned int) SKF_NET_OFF) {
49 print_xlat32(SKF_NET_OFF);
50 tprintf("+%u", fp->k - (unsigned int) SKF_NET_OFF);
52 } else if (fp->k >= (unsigned int) SKF_LL_OFF) {
53 print_xlat32(SKF_LL_OFF);
54 tprintf("+%u", fp->k - (unsigned int) SKF_LL_OFF);
63 print_sock_fprog(struct tcb *const tcp, const kernel_ulong_t addr,
64 const unsigned short len)
66 print_bpf_fprog(tcp, addr, len, print_sock_filter_k);
70 decode_sock_fprog(struct tcb *const tcp, const kernel_ulong_t addr)
72 decode_bpf_fprog(tcp, addr, print_sock_filter_k);