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Diffstat (limited to 'net/netfilter/xt_bpf.c')
-rw-r--r--net/netfilter/xt_bpf.c73
1 files changed, 73 insertions, 0 deletions
diff --git a/net/netfilter/xt_bpf.c b/net/netfilter/xt_bpf.c
new file mode 100644
index 00000000000..12d4da8e6c7
--- /dev/null
+++ b/net/netfilter/xt_bpf.c
@@ -0,0 +1,73 @@
+/* Xtables module to match packets using a BPF filter.
+ * Copyright 2013 Google Inc.
+ * Written by Willem de Bruijn <willemb@google.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/filter.h>
+
+#include <linux/netfilter/xt_bpf.h>
+#include <linux/netfilter/x_tables.h>
+
+MODULE_AUTHOR("Willem de Bruijn <willemb@google.com>");
+MODULE_DESCRIPTION("Xtables: BPF filter match");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("ipt_bpf");
+MODULE_ALIAS("ip6t_bpf");
+
+static int bpf_mt_check(const struct xt_mtchk_param *par)
+{
+ struct xt_bpf_info *info = par->matchinfo;
+ struct sock_fprog program;
+
+ program.len = info->bpf_program_num_elem;
+ program.filter = (struct sock_filter __user *) info->bpf_program;
+ if (sk_unattached_filter_create(&info->filter, &program)) {
+ pr_info("bpf: check failed: parse error\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static bool bpf_mt(const struct sk_buff *skb, struct xt_action_param *par)
+{
+ const struct xt_bpf_info *info = par->matchinfo;
+
+ return SK_RUN_FILTER(info->filter, skb);
+}
+
+static void bpf_mt_destroy(const struct xt_mtdtor_param *par)
+{
+ const struct xt_bpf_info *info = par->matchinfo;
+ sk_unattached_filter_destroy(info->filter);
+}
+
+static struct xt_match bpf_mt_reg __read_mostly = {
+ .name = "bpf",
+ .revision = 0,
+ .family = NFPROTO_UNSPEC,
+ .checkentry = bpf_mt_check,
+ .match = bpf_mt,
+ .destroy = bpf_mt_destroy,
+ .matchsize = sizeof(struct xt_bpf_info),
+ .me = THIS_MODULE,
+};
+
+static int __init bpf_mt_init(void)
+{
+ return xt_register_match(&bpf_mt_reg);
+}
+
+static void __exit bpf_mt_exit(void)
+{
+ xt_unregister_match(&bpf_mt_reg);
+}
+
+module_init(bpf_mt_init);
+module_exit(bpf_mt_exit);