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authorChris Zankel <chris@zankel.net>2014-02-24 00:34:36 -0800
committerChris Zankel <chris@zankel.net>2014-02-24 00:34:36 -0800
commitb3fdfc1b4b641d372e35ced98814289bc60bc5d1 (patch)
tree5f11d5ba885031dde45690745646519fb887f447 /tools/net/bpf_asm.c
parentc0e50d41126e4786d9cf1105bdf783e55c99f915 (diff)
parentf63b6d7555cd4064554b39da4d44c4cbbc9d6a4a (diff)
Merge tag 'xtensa-for-next-20140221-1' into for_next
Xtensa fixes for 3.14: - allow booting xtfpga on boards with new uBoot and >128MBytes memory; - drop nonexistent GPIO32 support from fsf variant; - don't select USE_GENERIC_SMP_HELPERS; - enable common clock framework support, set up ethoc clock on xtfpga; - wire up sched_setattr and sched_getattr syscalls. Signed-off-by: Chris Zankel <chris@zankel.net>
Diffstat (limited to 'tools/net/bpf_asm.c')
-rw-r--r--tools/net/bpf_asm.c52
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diff --git a/tools/net/bpf_asm.c b/tools/net/bpf_asm.c
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+/*
+ * Minimal BPF assembler
+ *
+ * Instead of libpcap high-level filter expressions, it can be quite
+ * useful to define filters in low-level BPF assembler (that is kept
+ * close to Steven McCanne and Van Jacobson's original BPF paper).
+ * In particular for BPF JIT implementors, JIT security auditors, or
+ * just for defining BPF expressions that contain extensions which are
+ * not supported by compilers.
+ *
+ * How to get into it:
+ *
+ * 1) read Documentation/networking/filter.txt
+ * 2) Run `bpf_asm [-c] <filter-prog file>` to translate into binary
+ * blob that is loadable with xt_bpf, cls_bpf et al. Note: -c will
+ * pretty print a C-like construct.
+ *
+ * Copyright 2013 Daniel Borkmann <borkmann@redhat.com>
+ * Licensed under the GNU General Public License, version 2.0 (GPLv2)
+ */
+
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+
+extern void bpf_asm_compile(FILE *fp, bool cstyle);
+
+int main(int argc, char **argv)
+{
+ FILE *fp = stdin;
+ bool cstyle = false;
+ int i;
+
+ for (i = 1; i < argc; i++) {
+ if (!strncmp("-c", argv[i], 2)) {
+ cstyle = true;
+ continue;
+ }
+
+ fp = fopen(argv[i], "r");
+ if (!fp) {
+ fp = stdin;
+ continue;
+ }
+
+ break;
+ }
+
+ bpf_asm_compile(fp, cstyle);
+
+ return 0;
+}