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/*
 * netsniff-ng - the packet sniffing beast
 * Copyright 2013 Daniel Borkmann.
 * Subject to the GPL, version 2.
 */

#include <pcap.h>
#include <linux/filter.h>

#include "xmalloc.h"
#include "config.h"
#include "bpf.h"
#include "die.h"

void bpf_try_compile(const char *rulefile, struct sock_fprog *bpf, uint32_t link_type)
{
	int i, ret;
	const struct bpf_insn *ins;
	struct sock_filter *out;
	struct bpf_program _bpf;

	ret = pcap_compile_nopcap(65535, link_type, &_bpf, rulefile, 1, 0xffffffff);
	if (ret < 0)
		panic("Cannot compile filter %s\n", rulefile);

	bpf->len = _bpf.bf_len;
	bpf->filter = xrealloc(bpf->filter, bpf->len * sizeof(*out));

	for (i = 0, ins = _bpf.bf_insns, out = bpf->filter; i < bpf->len;
	     ++i, ++ins, ++out) {
		out->code = ins->code;
		out->jt = ins->jt;
		out->jf = ins->jf;
		out->k = ins->k;

		if (out->code == 0x06 && out->k > 0)
			out->k = 0xFFFFFFFF;
	}

	pcap_freecode(&_bpf);

	if (__bpf_validate(bpf) == 0)
		panic("This is not a valid BPF program!\n");
}
69a1942b2b9b709bf66b944ff09f561484'>diff)
net: introduce device min_header_len
The stack must not pass packets to device drivers that are shorter than the minimum link layer header length. Previously, packet sockets would drop packets smaller than or equal to dev->hard_header_len, but this has false positives. Zero length payload is used over Ethernet. Other link layer protocols support variable length headers. Support for validation of these protocols removed the min length check for all protocols. Introduce an explicit dev->min_header_len parameter and drop all packets below this value. Initially, set it to non-zero only for Ethernet and loopback. Other protocols can follow in a patch to net-next. Fixes: 9ed988cd5915 ("packet: validate variable length ll headers") Reported-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Acked-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
-rw-r--r--include/linux/netdevice.h4
1 files changed, 4 insertions, 0 deletions
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h