Will be used to initialize the mptcp request socket when a MP_CAPABLE
request was handled in syncookie mode, i.e. when a TCP ACK containing a
MP_CAPABLE option is a valid syncookie value.
Normally (non-cookie case), MPTCP will generate a unique 32 bit connection
ID and stores it in the MPTCP token storage to be able to retrieve the
mptcp socket for subflow joining.
In syncookie case, we do not want to store any state, so just generate the
unique ID and use it in the reply.
This means there is a small window where another connection could generate
the same token.
When Cookie ACK comes back, we check that the token has not been registered
in the mean time. If it was, the connection needs to fall back to TCP.
Changes in v2:
- use req->syncookie instead of passing 'want_cookie' arg to ->init_req()
(Eric Dumazet)
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Once syncookie support is added, no state will be stored anymore when the
syn/ack is generated in syncookie mode.
When the ACK comes back, the generated key will be taken from the TCP ACK,
the token is re-generated and inserted into the token tree.
This means we can't retry with a new key when the token is already taken
in the syncookie case.
Therefore, move the retry logic to the caller to prepare for syncookie
support in mptcp.
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Otherwise the 'chain_len' filed will carry random values,
some token creation calls will fail due to excessive chain
length, causing unexpected fallback to TCP.
Fixes: 2c5ebd001d ("mptcp: refactor token container")
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Tested-by: Christoph Paasch <cpaasch@apple.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
mptcp_token_iter_next() allow traversing all the MPTCP
sockets inside the token container belonging to the given
network namespace with a quite standard iterator semantic.
That will be used by the next patch, but keep the API generic,
as we plan to use this later for PM's sake.
Additionally export mptcp_token_get_sock(), as it also
will be used by the diag module.
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Unit tests for the internal MPTCP token APIs, using KUNIT
v1 -> v2:
- use the correct RCU annotation when initializing icsk ulp
- fix a few checkpatch issues
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace the radix tree with a hash table allocated
at boot time. The radix tree has some shortcoming:
a single lock is contented by all the mptcp operation,
the lookup currently use such lock, and traversing
all the items would require a lock, too.
With hash table instead we trade a little memory to
address all the above - a per bucket lock is used.
To hash the MPTCP sockets, we re-use the msk' sk_node
entry: the MPTCP sockets are never hashed by the stack.
Replace the existing hash proto callbacks with a dummy
implementation, annotating the above constraint.
Additionally refactor the token creation to code to:
- limit the number of consecutive attempts to a fixed
maximum. Hitting a hash bucket with a long chain is
considered a failed attempt
- accept() no longer can fail to token management.
- if token creation fails at connect() time, we do
fallback to TCP (before the connection was closed)
v1 -> v2:
- fix "no newline at end of file" - Jakub
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Obtained with:
$ make W=1 net/mptcp/token.o
net/mptcp/token.c:53: warning: Function parameter or member 'req' not described in 'mptcp_token_new_request'
net/mptcp/token.c:98: warning: Function parameter or member 'sk' not described in 'mptcp_token_new_connect'
net/mptcp/token.c:133: warning: Function parameter or member 'conn' not described in 'mptcp_token_new_accept'
net/mptcp/token.c:178: warning: Function parameter or member 'token' not described in 'mptcp_token_destroy_request'
net/mptcp/token.c:191: warning: Function parameter or member 'token' not described in 'mptcp_token_destroy'
Fixes: 79c0949e9a (mptcp: Add key generation and token tree)
Fixes: 58b0991962 (mptcp: create msk early)
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Process the MP_JOIN option in a SYN packet with the same flow
as MP_CAPABLE but when the third ACK is received add the
subflow to the MPTCP socket subflow list instead of adding it to
the TCP socket accept queue.
The subflow is added at the end of the subflow list so it will not
interfere with the existing subflows operation and no data is
expected to be transmitted on it.
Co-developed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Peter Krystad <peter.krystad@linux.intel.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This change moves the mptcp socket allocation from mptcp_accept() to
subflow_syn_recv_sock(), so that subflow->conn is now always set
for the non fallback scenario.
It allows cleaning up a bit mptcp_accept() reducing the additional
locking and will allow fourther cleanup in the next patch.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Generate the local keys, IDSN, and token when creating a new socket.
Introduce the token tree to track all tokens in use using a radix tree
with the MPTCP token itself as the index.
Override the rebuild_header callback in inet_connection_sock_af_ops for
creating the local key on a new outgoing connection.
Override the init_req callback of tcp_request_sock_ops for creating the
local key on a new incoming connection.
Will be used to obtain the MPTCP parent socket to handle incoming joins.
Co-developed-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Co-developed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Peter Krystad <peter.krystad@linux.intel.com>
Signed-off-by: Christoph Paasch <cpaasch@apple.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Westphal