This patch extends {get|set}sockopt compatibility layer in order to
move protocol specific parts to their place and avoid huge universal
net/compat.c file in the future.
Signed-off-by: NDmitry Mishin <dim@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch implements an application of the LSM-IPSec networking
controls whereby an application can determine the label of the
security association its TCP or UDP sockets are currently connected to
via getsockopt and the auxiliary data mechanism of recvmsg.

Patch purpose:

This patch enables a security-aware application to retrieve the
security context of an IPSec security association a particular TCP or
UDP socket is using.  The application can then use this security
context to determine the security context for processing on behalf of
the peer at the other end of this connection.  In the case of UDP, the
security context is for each individual packet.  An example
application is the inetd daemon, which could be modified to start
daemons running at security contexts dependent on the remote client.

Patch design approach:

- Design for TCP
The patch enables the SELinux LSM to set the peer security context for
a socket based on the security context of the IPSec security
association.  The application may retrieve this context using
getsockopt.  When called, the kernel determines if the socket is a
connected (TCP_ESTABLISHED) TCP socket and, if so, uses the dst_entry
cache on the socket to retrieve the security associations.  If a
security association has a security context, the context string is
returned, as for UNIX domain sockets.

- Design for UDP
Unlike TCP, UDP is connectionless.  This requires a somewhat different
API to retrieve the peer security context.  With TCP, the peer
security context stays the same throughout the connection, thus it can
be retrieved at any time between when the connection is established
and when it is torn down.  With UDP, each read/write can have
different peer and thus the security context might change every time.
As a result the security context retrieval must be done TOGETHER with
the packet retrieval.

The solution is to build upon the existing Unix domain socket API for
retrieving user credentials.  Linux offers the API for obtaining user
credentials via ancillary messages (i.e., out of band/control messages
that are bundled together with a normal message).

Patch implementation details:

- Implementation for TCP
The security context can be retrieved by applications using getsockopt
with the existing SO_PEERSEC flag.  As an example (ignoring error
checking):

getsockopt(sockfd, SOL_SOCKET, SO_PEERSEC, optbuf, &optlen);
printf("Socket peer context is: %s\n", optbuf);

The SELinux function, selinux_socket_getpeersec, is extended to check
for labeled security associations for connected (TCP_ESTABLISHED ==
sk->sk_state) TCP sockets only.  If so, the socket has a dst_cache of
struct dst_entry values that may refer to security associations.  If
these have security associations with security contexts, the security
context is returned.

getsockopt returns a buffer that contains a security context string or
the buffer is unmodified.

- Implementation for UDP
To retrieve the security context, the application first indicates to
the kernel such desire by setting the IP_PASSSEC option via
getsockopt.  Then the application retrieves the security context using
the auxiliary data mechanism.

An example server application for UDP should look like this:

toggle = 1;
toggle_len = sizeof(toggle);

setsockopt(sockfd, SOL_IP, IP_PASSSEC, &toggle, &toggle_len);
recvmsg(sockfd, &msg_hdr, 0);
if (msg_hdr.msg_controllen > sizeof(struct cmsghdr)) {
    cmsg_hdr = CMSG_FIRSTHDR(&msg_hdr);
    if (cmsg_hdr->cmsg_len <= CMSG_LEN(sizeof(scontext)) &&
        cmsg_hdr->cmsg_level == SOL_IP &&
        cmsg_hdr->cmsg_type == SCM_SECURITY) {
        memcpy(&scontext, CMSG_DATA(cmsg_hdr), sizeof(scontext));
    }
}

ip_setsockopt is enhanced with a new socket option IP_PASSSEC to allow
a server socket to receive security context of the peer.  A new
ancillary message type SCM_SECURITY.

When the packet is received we get the security context from the
sec_path pointer which is contained in the sk_buff, and copy it to the
ancillary message space.  An additional LSM hook,
selinux_socket_getpeersec_udp, is defined to retrieve the security
context from the SELinux space.  The existing function,
selinux_socket_getpeersec does not suit our purpose, because the
security context is copied directly to user space, rather than to
kernel space.

Testing:

We have tested the patch by setting up TCP and UDP connections between
applications on two machines using the IPSec policies that result in
labeled security associations being built.  For TCP, we can then
extract the peer security context using getsockopt on either end.  For
UDP, the receiving end can retrieve the security context using the
auxiliary data mechanism of recvmsg.
Signed-off-by: NCatherine Zhang <cxzhang@watson.ibm.com>
Acked-by: NJames Morris <jmorris@namei.org>
Acked-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Back in the dark ages, we had to be conservative and only allow 15-bit
window fields if the window scale option was not negotiated.  Some
ancient stacks used a signed 16-bit quantity for the window field of
the TCP header and would get confused.

Those days are long gone, so we can use the full 16-bits by default
now.

There is a sysctl added so that we can still interact with such old
stacks
Signed-off-by: NRick Jones <rick.jones2@hp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/netfilter/ip_nat_snmp_basic.c: In function 'asn1_header_decode':
net/ipv4/netfilter/ip_nat_snmp_basic.c:248: warning: 'len' may be used uninitialized in this function
net/ipv4/netfilter/ip_nat_snmp_basic.c:248: warning: 'def' may be used uninitialized in this function
net/ipv4/netfilter/ip_nat_snmp_basic.c: In function 'snmp_translate':
net/ipv4/netfilter/ip_nat_snmp_basic.c:672: warning: 'l' may be used uninitialized in this function
net/ipv4/netfilter/ip_nat_snmp_basic.c:668: warning: 'type' may be used uninitialized in this function
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Semaphore to mutex conversion.

The conversion was generated via scripts, and the result was validated
automatically via a script as well.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Semaphore to mutex conversion.

The conversion was generated via scripts, and the result was validated
automatically via a script as well.
Signed-off-by: NArjan van de Ven <arjan@infradead.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Get rid of the old __dev_put macro that is just a hold over from pre 2.6
kernel.  And turn dev_hold into an inline instead of a macro.
Signed-off-by: NStephen Hemminger <shemminger@osdl.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch turns the RTNL from a semaphore to a new 2.6.16 mutex and
gets rid of some of the leftover legacy.
Signed-off-by: NStephen Hemminger <shemminger@osdl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Instead of estimating the time since the last congestion event, count
it directly.
Signed-off-by: NBaruch Even <baruch@ev-en.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Account for delayed-ACKs in H-TCP.

Delayed-ACKs cause H-TCP to be less aggressive than its design calls
for. It is especially true when the receiver is a Linux machine where
the average delayed ack is over 3 packets with values of 7 not unheard
of.
Signed-off-By: NBaruch Even <baruch@ev-en.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use functions to calculate jiffies from milliseconds and not the old,
crude method of dividing HZ by a value. Ensures more accurate values
even in the face of strange HZ values.
Signed-off-By: NBaruch Even <baruch@ev-en.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Consolidating open coded sequences in tcp and dccp, v4 and v6.
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

fib_triestats has been buggy and caused oopses some platforms as
openwrt.  The patch below should cure those problems.
Signed-off-by: NRobert Olsson <robert.olsson@its.uu.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In some kernel configs /proc functions seems to be accessed before the
trie is initialized. The patch below checks for this.
Signed-off-by: NRobert Olsson <robert.olsson@its.uu.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This moves some TCP-specific MTU probing state out of
inet_connection_sock back to tcp_sock.
Signed-off-by: NJohn Heffner <jheffner@psc.edu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The bridge netfilter code simulates the NF_IP_PRE_ROUTING hook and skips
the real hook by registering with high priority and returning NF_STOP if
skb->nf_bridge is present and the BRNF_NF_BRIDGE_PREROUTING flag is not
set. The flag is only set during the simulated hook.

Because skb->nf_bridge is only freed when the packet is destroyed, the
packet will not only skip the first invocation of NF_IP_PRE_ROUTING, but
in the case of tunnel devices on top of the bridge also all further ones.
Forwarded packets from a bridge encapsulated by a tunnel device and sent
as locally outgoing packet will also still have the incorrect bridge
information from the input path attached.

We already have nf_reset calls on all RX/TX paths of tunnel devices,
so simply reset the nf_bridge field there too. As an added bonus,
the bridge information for locally delivered packets is now also freed
when the packet is queued to a socket.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fast path sequence updates that will generate ipsec async
events
Signed-off-by: NJamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Avoid unneccessary event message generation by checking for netlink
listeners before building a message.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This allows to make decisions based on the revision (and address family
with a follow-up patch) at runtime.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The recent (kernel 2.6.15.1) fix for PPTP NAT helper introduced a
bug - which only appears if DEBUGP is enabled though.

The calculation of the CID offset into a PPTP request struct is
not correct, so that at least not the correct CID is displayed
if DEBUGP is enabled.

This patch corrects CID offset calculation and introduces a #define
for that.
Signed-off-by: NHolger Eitzenberger <heitzenberger@astaro.com>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch moves all helper related data fields of 'struct nf_conn'
into a separate structure 'struct nf_conn_help'.  This new structure
is only present in conntrack entries for which we actually have a
helper loaded.

Also, this patch cleans up the nf_conntrack 'features' mechanism to
resemble what the original idea was: Just glue the feature-specific
data structures at the end of 'struct nf_conn', and explicitly
re-calculate the pointer to it when needed rather than keeping
pointers around.

Saves 20 bytes per conntrack on my x86_64 box. A non-helped conntrack
is 276 bytes. We still need to save another 20 bytes in order to fit
into to target of 256bytes.
Signed-off-by: NHarald Welte <laforge@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Implementation of packetization layer path mtu discovery for TCP, based on
the internet-draft currently found at
<http://www.ietf.org/internet-drafts/draft-ietf-pmtud-method-05.txt>.
Signed-off-by: NJohn Heffner <jheffner@psc.edu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

struct fib_rules became global for no good reason.
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NRobert Olsson <robert.olsson@its.uu.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The check is wrong and lets NULL-ptrs slip through since !IS_ERR(NULL)
is true.

Coverity #190
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When ufo_append_data fails err is uninitialized, but returned back.
Strangely gcc doesn't notice it.

Coverity #901 and #902
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Covertiy #547
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

That's >= a full sized TSO frame, so we should always
return 0 in that case.

Based upon a report and initial patch from Lachlan
Andrew, final patch suggested by Herbert Xu.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The size of the skb carrying the netlink message is not
equivalent to the length of the actual netlink message
due to padding. ip_queue matches the length of the payload
against the original packet size to determine if packet
mangling is desired, due to the above wrong assumption
arbitary packets may not be mangled depening on their
original size.
Signed-off-by: NThomas Graf <tgraf@suug.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The nfnetlink_log infrastructure changes broke compatiblity of the LOG
targets. They currently use whatever log backend was registered first,
which means that if ipt_ULOG was loaded first, no messages will be printed
to the ring buffer anymore.

Restore compatiblity by using the old log functions by default and only use
the nf_log backend if the user explicitly said so.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The only reason post_input exists at all is that it gives us the
potential to adjust the checksums incrementally in future which
we ought to do.

However, after thinking about it for a bit we can adjust the
checksums without using this post_input stuff at all.  The crucial
point is that only the inner-most NAT-T SA needs to be considered
when adjusting checksums.  What's more, the checksum adjustment
comes down to a single u32 due to the linearity of IP checksums.

We just happen to have a spare u32 lying around in our skb structure :)
When ip_summed is set to CHECKSUM_NONE on input, the value of skb->csum
is currently unused.  All we have to do is to make that the checksum
adjustment and voila, there goes all the post_input and decap structures!

I've left in the decap data structures for now since it's intricately
woven into the sec_path stuff.  We can kill them later too.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We used to keep sg on the stack which is why the extra block was useful.
We've long since stopped doing that so let's kill the block and save
some indentation.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We should use the TOS because it's one of the routing keys.  It also
means that we update the correct routing cache entry when PMTU occurs.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When garbage collecting route cache entries of multipath routes
in rt_garbage_collect(), entries were deleted from the hash bucket
'i' while holding a spin lock on bucket 'k' resulting in a system
hang.  Delete entries, if any, from bucket 'k' instead.
Signed-off-by: NSuresh Bhogavilli <sbhogavilli@verisign.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>