From mboxrd@z Thu Jan 1 00:00:00 1970 From: Willem de Bruijn Subject: [PATCH] [rfc] a bpf compilation tool for xt_bpf Date: Sun, 9 Dec 2012 17:52:38 -0500 Message-ID: <1355093558-27931-1-git-send-email-willemb@google.com> References: <1355082854-31853-1-git-send-email-willemb@google.com> Cc: Willem de Bruijn To: netfilter-devel@vger.kernel.org, pablo@netfilter.org Return-path: Received: from mail-bk0-f74.google.com ([209.85.214.74]:35489 "EHLO mail-bk0-f74.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934578Ab2LIWwr (ORCPT ); Sun, 9 Dec 2012 17:52:47 -0500 Received: by mail-bk0-f74.google.com with SMTP id je9so133988bkc.1 for ; Sun, 09 Dec 2012 14:52:45 -0800 (PST) In-Reply-To: <1355082854-31853-1-git-send-email-willemb@google.com> Sender: netfilter-devel-owner@vger.kernel.org List-ID: An example tool to convert textual BPF into the instructions acceptable by xt_bpf. This is mostly boilerplate around existing pcap calls. I do not intend this for submission as is. It adds a dependency on pcap, which would at the least have to be optional and detected by autoconf. --- utils/Makefile.am | 3 ++- utils/bpf_compile.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 49 insertions(+), 1 deletions(-) create mode 100644 utils/bpf_compile.c diff --git a/utils/Makefile.am b/utils/Makefile.am index f1bbfc5..4c67292 100644 --- a/utils/Makefile.am +++ b/utils/Makefile.am @@ -4,7 +4,8 @@ AM_CFLAGS = ${regular_CFLAGS} AM_CPPFLAGS = ${regular_CPPFLAGS} -I${top_builddir}/include \ -I${top_srcdir}/include ${libnfnetlink_CFLAGS} -sbin_PROGRAMS = nfnl_osf +sbin_PROGRAMS = nfnl_osf bpf_compile pkgdata_DATA = pf.os nfnl_osf_LDADD = -lnfnetlink +bpf_compile_LDADD = -lpcap diff --git a/utils/bpf_compile.c b/utils/bpf_compile.c new file mode 100644 index 0000000..62f7bc8 --- /dev/null +++ b/utils/bpf_compile.c @@ -0,0 +1,47 @@ +/* + * BPF program compilation tool + * + * Written by Willem de Bruijn (willemb@google.com) + * Copyright Google, Inc. 2012 + * Licensed under the GNU General Public License version 2 (GPLv2) +*/ + +#include +#include + +int main(int argc, char **argv) +{ + struct bpf_program program; + struct bpf_insn *ins; + int i, dlt = DLT_RAW; + + if (argc < 2 || argc > 3) { + fprintf(stderr, "Usage: %s [linktype] \n" + " linktype is one of EN10MB, RAW, ...\n" + " program must be one parameter\n", + argv[0]); + return 1; + } + + if (argc == 3) { + dlt = pcap_datalink_name_to_val(argv[1]); + if (dlt == -1) { + fprintf(stderr, "Unknown datalinktype: %s\n", argv[1]); + return 1; + } + } + + printf("Using datalinktype %s\n", pcap_datalink_val_to_name(dlt)); + if (pcap_compile_nopcap(65535, dlt, &program, argv[argc - 1], 1, 0)) { + fprintf(stderr, "Compilation error\n"); + return 1; + } + + printf("%d\n", program.bf_len); + ins = program.bf_insns; + for (i = 0; i < program.bf_len; ++ins, ++i) + printf("%u %u %u %u\n", ins->code, ins->jt, ins->jf, ins->k); + + return 0; +} + -- 1.7.7.3