Add new sockopt to reserve some headroom in the mmaped ring frames in
front of the packet payload. This can be used f.i. when the VLAN header
needs to be (re)constructed to avoid moving the entire payload.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Store the VLAN tag in the auxillary data/tpacket2_hdr so userspace can
properly deal with hardware VLAN tagging/stripping.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The tpacket_hdr is not 64 bit clean due to use of an unsigned long
and can't be extended because the following struct sockaddr_ll needs
to be at a fixed offset.
Add support for a version 2 tpacket protocol that removes these
limitations.
Userspace can query the header size through a new getsockopt option
and change the protocol version through a setsockopt option. The
changes needed to switch to the new protocol version are:
1. replace struct tpacket_hdr by struct tpacket2_hdr
2. query header len and save
3. set protocol version to 2
- set up ring as usual
4. for getting the sockaddr_ll, use (void *)hdr + TPACKET_ALIGN(hdrlen)
instead of (void *)hdr + TPACKET_ALIGN(sizeof(struct tpacket_hdr))
Steps 2 and 4 can be omitted if the struct sockaddr_ll isn't needed.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a packet socket option to allow the orig_dev index to be returned
to userspace when passing traffic through a decapsulated device, such
as the bonding driver.
This is very useful for layer 2 traffic being able to report which
physical device actually received the traffic, instead of having the
encapsulating device hide that information.
The new option is called PACKET_ORIGDEV.
Signed-off-by: Peter P. Waskiewicz Jr. <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is needed to make ISC's DHCP server (and probably other
DHCP servers/clients using AF_PACKET) to be able to serve another
client on the same Xen host.
The problem is that packets between different domains on the same
Xen host only have partial checksums. Unfortunately this piece of
information is not passed along in AF_PACKET unless you're using
the mmap interface. Since dhcpd doesn't support packet-mmap, UDP
packets from the same host come out with apparently bogus checksums.
This patch adds a mechanism for AF_PACKET recvmsg(2) to return the
status along with the packet. It does so by adding a new cmsg that
contains this information along with some other relevant data such
as the original packet length.
I didn't include the time stamp information since there is already
a cmsg for that.
This patch also changes the mmap code to set the CSUMNOTREADY flag
on all packets instead of just outoing packets on cooked sockets.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Weirdness: the third argument of socket() is net-endian
here. Oh, well - it's documented in packet(7).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Patrick McHardy