This patch adds a new socket option, TCP_FASTOPEN_CONNECT, as an
alternative way to perform Fast Open on the active side (client). Prior
to this patch, a client needs to replace the connect() call with
sendto(MSG_FASTOPEN). This can be cumbersome for applications who want
to use Fast Open: these socket operations are often done in lower layer
libraries used by many other applications. Changing these libraries
and/or the socket call sequences are not trivial. A more convenient
approach is to perform Fast Open by simply enabling a socket option when
the socket is created w/o changing other socket calls sequence:
  s = socket()
    create a new socket
  setsockopt(s, IPPROTO_TCP, TCP_FASTOPEN_CONNECT …);
    newly introduced sockopt
    If set, new functionality described below will be used.
    Return ENOTSUPP if TFO is not supported or not enabled in the
    kernel.

  connect()
    With cookie present, return 0 immediately.
    With no cookie, initiate 3WHS with TFO cookie-request option and
    return -1 with errno = EINPROGRESS.

  write()/sendmsg()
    With cookie present, send out SYN with data and return the number of
    bytes buffered.
    With no cookie, and 3WHS not yet completed, return -1 with errno =
    EINPROGRESS.
    No MSG_FASTOPEN flag is needed.

  read()
    Return -1 with errno = EWOULDBLOCK/EAGAIN if connect() is called but
    write() is not called yet.
    Return -1 with errno = EWOULDBLOCK/EAGAIN if connection is
    established but no msg is received yet.
    Return number of bytes read if socket is established and there is
    msg received.

The new API simplifies life for applications that always perform a write()
immediately after a successful connect(). Such applications can now take
advantage of Fast Open by merely making one new setsockopt() call at the time
of creating the socket. Nothing else about the application's socket call
sequence needs to change.
Signed-off-by: NWei Wang <weiwan@google.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Acked-by: NYuchung Cheng <ycheng@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Refactor the cookie check logic in tcp_send_syn_data() into a function.
This function will be called else where in later changes.
Signed-off-by: NWei Wang <weiwan@google.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Acked-by: NYuchung Cheng <ycheng@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This work adds a number of tracepoints to paths that are either
considered slow-path or exception-like states, where monitoring or
inspecting them would be desirable.

For bpf(2) syscall, tracepoints have been placed for main commands
when they succeed. In XDP case, tracepoint is for exceptions, that
is, f.e. on abnormal BPF program exit such as unknown or XDP_ABORTED
return code, or when error occurs during XDP_TX action and the packet
could not be forwarded.

Both have been split into separate event headers, and can be further
extended. Worst case, if they unexpectedly should get into our way in
future, they can also removed [1]. Of course, these tracepoints (like
any other) can be analyzed by eBPF itself, etc. Example output:

  # ./perf record -a -e bpf:* sleep 10
  # ./perf script
  sock_example  6197 [005]   283.980322:      bpf:bpf_map_create: map type=ARRAY ufd=4 key=4 val=8 max=256 flags=0
  sock_example  6197 [005]   283.980721:       bpf:bpf_prog_load: prog=a5ea8fa30ea6849c type=SOCKET_FILTER ufd=5
  sock_example  6197 [005]   283.988423:   bpf:bpf_prog_get_type: prog=a5ea8fa30ea6849c type=SOCKET_FILTER
  sock_example  6197 [005]   283.988443: bpf:bpf_map_lookup_elem: map type=ARRAY ufd=4 key=[06 00 00 00] val=[00 00 00 00 00 00 00 00]
  [...]
  sock_example  6197 [005]   288.990868: bpf:bpf_map_lookup_elem: map type=ARRAY ufd=4 key=[01 00 00 00] val=[14 00 00 00 00 00 00 00]
       swapper     0 [005]   289.338243:    bpf:bpf_prog_put_rcu: prog=a5ea8fa30ea6849c type=SOCKET_FILTER

  [1] https://lwn.net/Articles/705270/Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For upcoming tracepoint support for BPF, we want to dump the program's
tag. Format should be similar to __print_hex(), but without spacing.
Add a __print_hex_str() variant for exactly that purpose that reuses
trace_print_hex_seq().
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Introduce optional 128-bit action cookie.
Like all other cookie schemes in the networking world (eg in protocols
like http or existing kernel fib protocol field, etc) the idea is to save
user state that when retrieved serves as a correlator. The kernel
_should not_ intepret it.  The user can store whatever they wish in the
128 bits.

Sample exercise(showing variable length use of cookie)

.. create an accept action with cookie a1b2c3d4
sudo $TC actions add action ok index 1 cookie a1b2c3d4

.. dump all gact actions..
sudo $TC -s actions ls action gact

    action order 0: gact action pass
     random type none pass val 0
     index 1 ref 1 bind 0 installed 5 sec used 5 sec
    Action statistics:
    Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
    backlog 0b 0p requeues 0
    cookie a1b2c3d4

.. bind the accept action to a filter..
sudo $TC filter add dev lo parent ffff: protocol ip prio 1 \
u32 match ip dst 127.0.0.1/32 flowid 1:1 action gact index 1

... send some traffic..
$ ping 127.0.0.1 -c 3
PING 127.0.0.1 (127.0.0.1) 56(84) bytes of data.
64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.020 ms
64 bytes from 127.0.0.1: icmp_seq=2 ttl=64 time=0.027 ms
64 bytes from 127.0.0.1: icmp_seq=3 ttl=64 time=0.038 ms
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When programs need to calculate the csum from scratch for small UDP
packets and use bpf_l4_csum_replace() to feed the result from helpers
like bpf_csum_diff(), then we need a flag besides BPF_F_MARK_MANGLED_0
that would ignore the case of current csum being 0, and which would
still allow for the helper to set the csum and transform when needed
to CSUM_MANGLED_0.
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For some mlx5 HW models (CX4, CX4Lx), the VF driver needs to put part
of the packet headers on the TX descriptor so the e-switch can do proper
matching and steering. This is called "min-inline", it's advertized to
the VF by the FW and also enforced on them by the HW, such that if they
don't obey, their packets are dropped.

SRIOV VF libmlx5 instances should take into account the min-inline
value of their vports. For that end, we provide this value through
the vendor response part of init_ucontext command.

The min inline value is reported in a way which will let newer libmlx5
instances realize that they are running over an older kernel and act
accordingly (e.g apply some educated guess).
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: NMatan Barak <matanb@mellanox.com>
Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>

So we can use that from the IB driver too in downstream patches.

This patch doesn't change any functionality.
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>

Add support for SRIOV VF min rate guarantee by using the TSAR BW share
weights mechanism.

The TSAR BW share vport attribute represents the weight of that vport
among the other vports weights which means that the actual vport BW
percentage is the same vport weight percentage among the total vports
weights sum.
Signed-off-by: NMohamad Haj Yahia <mohamad@mellanox.com>
Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>

This action allows the user to sample traffic matched by tc classifier.
The sampling consists of choosing packets randomly and sampling them using
the psample module. The user can configure the psample group number, the
sampling rate and the packet's truncation (to save kernel-user traffic).

Example:
To sample ingress traffic from interface eth1, one may use the commands:

tc qdisc add dev eth1 handle ffff: ingress

tc filter add dev eth1 parent ffff: \
	   matchall action sample rate 12 group 4

Where the first command adds an ingress qdisc and the second starts
sampling randomly with an average of one sampled packet per 12 packets on
dev eth1 to psample group 4.
Signed-off-by: NYotam Gigi <yotamg@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a general way for kernel modules to sample packets, without being tied
to any specific subsystem. This netlink channel can be used by tc,
iptables, etc. and allow to standardize packet sampling in the kernel.

For every sampled packet, the psample module adds the following metadata
fields:

PSAMPLE_ATTR_IIFINDEX - the packets input ifindex, if applicable

PSAMPLE_ATTR_OIFINDEX - the packet output ifindex, if applicable

PSAMPLE_ATTR_ORIGSIZE - the packet's original size, in case it has been
   truncated during sampling

PSAMPLE_ATTR_SAMPLE_GROUP - the packet's sample group, which is set by the
   user who initiated the sampling. This field allows the user to
   differentiate between several samplers working simultaneously and
   filter packets relevant to him

PSAMPLE_ATTR_GROUP_SEQ - sequence counter of last sent packet. The
   sequence is kept for each group

PSAMPLE_ATTR_SAMPLE_RATE - the sampling rate used for sampling the packets

PSAMPLE_ATTR_DATA - the actual packet bits

The sampled packets are sent to the PSAMPLE_NL_MCGRP_SAMPLE multicast
group. In addition, add the GET_GROUPS netlink command which allows the
user to see the current sample groups, their refcount and sequence number.
This command currently supports only netlink dump mode.
Signed-off-by: NYotam Gigi <yotamg@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Reviewed-by: NJamal Hadi Salim <jhs@mojatatu.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The module boilerplate macro is named mdio_module_driver and not
module_mdio_driver, fix that.

Fixes: a9049e0c ("mdio: Add support for mdio drivers.")
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Implements an optional, per bridge port flag and feature to deliver
multicast packets to any host on the according port via unicast
individually. This is done by copying the packet per host and
changing the multicast destination MAC to a unicast one accordingly.

multicast-to-unicast works on top of the multicast snooping feature of
the bridge. Which means unicast copies are only delivered to hosts which
are interested in it and signalized this via IGMP/MLD reports
previously.

This feature is intended for interface types which have a more reliable
and/or efficient way to deliver unicast packets than broadcast ones
(e.g. wifi).

However, it should only be enabled on interfaces where no IGMPv2/MLDv1
report suppression takes place. This feature is disabled by default.

The initial patch and idea is from Felix Fietkau.
Signed-off-by: NFelix Fietkau <nbd@nbd.name>
[linus.luessing@c0d3.blue: various bug + style fixes, commit message]
Signed-off-by: NLinus Lüssing <linus.luessing@c0d3.blue>
Reviewed-by: NNikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add net.ipv4.ip_unprivileged_port_start, which is a per namespace sysctl
that denotes the first unprivileged inet port in the namespace.  To
disable all privileged ports set this to zero.  It also checks for
overlap with the local port range.  The privileged and local range may
not overlap.

The use case for this change is to allow containerized processes to bind
to priviliged ports, but prevent them from ever being allowed to modify
their container's network configuration.  The latter is accomplished by
ensuring that the network namespace is not a child of the user
namespace.  This modification was needed to allow the container manager
to disable a namespace's priviliged port restrictions without exposing
control of the network namespace to processes in the user namespace.
Signed-off-by: NKrister Johansen <kjlx@templeofstupid.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This trie implements a longest prefix match algorithm that can be used
to match IP addresses to a stored set of ranges.

Internally, data is stored in an unbalanced trie of nodes that has a
maximum height of n, where n is the prefixlen the trie was created
with.

Tries may be created with prefix lengths that are multiples of 8, in
the range from 8 to 2048. The key used for lookup and update operations
is a struct bpf_lpm_trie_key, and the value is a uint64_t.

The code carries more information about the internal implementation.
Signed-off-by: NDaniel Mack <daniel@zonque.org>
Reviewed-by: NDavid Herrmann <dh.herrmann@gmail.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support for the BCM7278 28nm process Gigabit Ethernet PHY.
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Only the Marvell mv88e6xxx DSA driver made use of the HWMON support in
DSA. The temperature sensor registers are actually in the embedded
PHYs, and the PHY driver now supports it. So remove all HWMON support
from DSA and drivers.
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Cast second parameter of csum_sub() from __sum16 to __wsum.
Signed-off-by: NLance Richardson <lrichard@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If the bearer carrying multicast messages supports broadcast, those
messages will be sent to all cluster nodes, irrespective of whether
these nodes host any actual destinations socket or not. This is clearly
wasteful if the cluster is large and there are only a few real
destinations for the message being sent.

In this commit we extend the eligibility of the newly introduced
"replicast" transmit option. We now make it possible for a user to
select which method he wants to be used, either as a mandatory setting
via setsockopt(), or as a relative setting where we let the broadcast
layer decide which method to use based on the ratio between cluster
size and the message's actual number of destination nodes.

In the latter case, a sending socket must stick to a previously
selected method until it enters an idle period of at least 5 seconds.
This eliminates the risk of message reordering caused by method change,
i.e., when changes to cluster size or number of destinations would
otherwise mandate a new method to be used.
Reviewed-by: NParthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Provide a simple helper with the same semantics of strncpy_from_unsafe():

int bpf_probe_read_str(void *dst, int size, const void *unsafe_addr)

This gives more flexibility to a bpf program. A typical use case is
intercepting a file name during sys_open(). The current approach is:

SEC("kprobe/sys_open")
void bpf_sys_open(struct pt_regs *ctx)
{
	char buf[PATHLEN]; // PATHLEN is defined to 256
	bpf_probe_read(buf, sizeof(buf), ctx->di);

	/* consume buf */
}

This is suboptimal because the size of the string needs to be estimated
at compile time, causing more memory to be copied than often necessary,
and can become more problematic if further processing on buf is done,
for example by pushing it to userspace via bpf_perf_event_output(),
since the real length of the string is unknown and the entire buffer
must be copied (and defining an unrolled strnlen() inside the bpf
program is a very inefficient and unfeasible approach).

With the new helper, the code can easily operate on the actual string
length rather than the buffer size:

SEC("kprobe/sys_open")
void bpf_sys_open(struct pt_regs *ctx)
{
	char buf[PATHLEN]; // PATHLEN is defined to 256
	int res = bpf_probe_read_str(buf, sizeof(buf), ctx->di);

	/* consume buf, for example push it to userspace via
	 * bpf_perf_event_output(), but this time we can use
	 * res (the string length) as event size, after checking
	 * its boundaries.
	 */
}

Another useful use case is when parsing individual process arguments or
individual environment variables navigating current->mm->arg_start and
current->mm->env_start: using this helper and the return value, one can
quickly iterate at the right offset of the memory area.

The code changes simply leverage the already existent
strncpy_from_unsafe() kernel function, which is safe to be called from a
bpf program as it is used in bpf_trace_printk().
Signed-off-by: NGianluca Borello <g.borello@gmail.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that pci_bus_type has num_vf callback set, dev_num_vf can be
implemented in a bus type independent way and the check for whether a
PCI device is being handled in rtnetlink can be dropped.
Signed-off-by: NPhil Sutter <phil@nwl.cc>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This allows for bus types to implement their own method of retrieving
the number of virtual functions a NIC on that type of bus supports.
Signed-off-by: NPhil Sutter <phil@nwl.cc>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use hlist_entry_safe() instead of open-coding it.
Signed-off-by: NGeliang Tang <geliangtang@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Shaohua Li made percpu_counter irq safe in commit 098faf58
("percpu_counter: make APIs irq safe")

We can safely remove BH disable/enable sections around various
percpu_counter manipulations.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The caps structure consists of hca caps and port/management caps,
all under one roof.
Signed-off-by: NGal Pressman <galp@mellanox.com>
Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>

Add the needed infrastructure for future use of MPCNT register.
Signed-off-by: NGal Pressman <galp@mellanox.com>
Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>

Add the needed infrastructure for future use of PPCNT physical layer
statistical group.
Signed-off-by: NGal Pressman <galp@mellanox.com>
Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>
Signed-off-by: NLeon Romanovsky <leon@kernel.org>

On load_one, we now cache our capabilities registers internally, similar
to QUERY_HCA_CAP. Capabilities can later be queried using macros
introduced in this patch.
Signed-off-by: NGal Pressman <galp@mellanox.com>
Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>

PCAM: Ports capabilities mask register.
MCAM: Management capabilities mask register.

PCAM and MCAM registers will provide information regarding firmware
support for different features, in order to avoid cases where new driver
combined with old firmware results in syndromes (for ex. PCIe counters
before this patchset).
Signed-off-by: NGal Pressman <galp@mellanox.com>
Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>

Add svlan_tag and rename vlan_tag to cvlan_tag in flow table entry
match param.
Signed-off-by: NMohamad Haj Yahia <mohamad@mellanox.com>
Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>

Implement query and set functionality for MTPPS and MTPPSE registers.
MTPPS (Management Pulse Per Second) provides the device PPS capabilities,
configures the PPS in and out modules and holds the PPS in time stamp.
Query MTPPS is supported only when HCA_CAP.pps is set and modify is supported
when HCA_CAP.pps_modify is set.

MTPPSE (Management Pulse Per Second Event) configures the different event
generation modes for PPS. Supported when HCA_CAP.pps is set.
Signed-off-by: NEugenia Emantayev <eugenia@mellanox.com>
Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>

Some bus names are pretty long and do not fit into
17 chars. Increase therefore MII_BUS_ID_SIZE and
phy_fixup.bus_id to larger number. Now mii_bus.id
can host larger name.
Signed-off-by: NVolodymyr Bendiuga <volodymyr.bendiuga@gmail.com>
Signed-off-by: NMagnus Öberg <magnus.oberg@westermo.se>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The network stack no longer uses the last_rx member of struct net_device
since the bonding driver switched to use its own private last_rx in
commit 9f242738 ("bonding: use last_arp_rx in slave_last_rx()").

However, some drivers still (ab)use the field for their own purposes and
some driver just update it without actually using it.

Previously, there was an accompanying comment for the last_rx member
added in commit 4dc89133 ("net: add a comment on netdev->last_rx")
which asked drivers not to update is, unless really needed. However,
this commend was removed in commit f8ff080d ("bonding: remove
useless updating of slave->dev->last_rx"), so some drivers added later
on still did update last_rx.

Remove all usage of last_rx and switch three drivers (sky2, atp and
smc91c92_cs) which actually read and write it to use their own private
copy in netdev_priv.

Compile-tested with allyesconfig and allmodconfig on x86 and arm.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Jay Vosburgh <j.vosburgh@gmail.com>
Cc: Veaceslav Falico <vfalico@gmail.com>
Cc: Andy Gospodarek <andy@greyhouse.net>
Cc: Mirko Lindner <mlindner@marvell.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Acked-by: NEric Dumazet <edumazet@google.com>
Reviewed-by: NJay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Store a dsa_switch pointer to the CPU switch in the tree instead of only
its index. This avoids the need to initialize it to -1.
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

All callers of rt6_fill_node pass 0 for nowait arg. Remove the arg and
simplify rt6_fill_node accordingly.

rt6_fill_node passes the nowait of 0 to ip6mr_get_route. Remove the
nowait arg from it as well.
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch is to implement sender-side procedures for the Outgoing
and Incoming SSN Reset Request Parameter described in rfc6525 section
5.1.2 and 5.1.3.

It is also add sockopt SCTP_RESET_STREAMS in rfc6525 section 6.3.2
for users.

Note that the new asoc member strreset_outstanding is to make sure
only one reconf request chunk on the fly as rfc6525 section 5.1.1
demands.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch is to add sockopt SCTP_ENABLE_STREAM_RESET to get/set
strreset_enable to indicate which reconf request type it supports,
which is described in rfc6525 section 6.3.1.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch is to add reconf_enable field in all of asoc ep and netns
to indicate if they support stream reset.

When initializing, asoc reconf_enable get the default value from ep
reconf_enable which is from netns netns reconf_enable by default.

It is also to add reconf_capable in asoc peer part to know if peer
supports reconf_enable, the value is set if ext params have reconf
chunk support when processing init chunk, just as rfc6525 section
5.1.1 demands.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch is to add a primitive based on sctp primitive frame for
sending stream reconf request. It works as the other primitives,
and create a SCTP_CMD_REPLY command to send the request chunk out.

sctp_primitive_RECONF would be the api to send a reconf request
chunk.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch is to add a per transport timer based on sctp timer frame
for stream reconf chunk retransmission. It would start after sending
a reconf request chunk, and stop after receiving the response chunk.

If the timer expires, besides retransmitting the reconf request chunk,
it would also do the same thing with data RTO timer. like to increase
the appropriate error counts, and perform threshold management, possibly
destroying the asoc if sctp retransmission thresholds are exceeded, just
as section 5.1.1 describes.

This patch is also to add asoc strreset_chunk, it is used to save the
reconf request chunk, so that it can be retransmitted, and to check if
the response is really for this request by comparing the information
inside with the response chunk as well.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>