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2020-07-28mptcp: Skip unnecessary skb extension allocation for bare acksMat Martineau
Bare TCP ack skbs are freed right after MPTCP sees them, so the work to allocate, zero, and populate the MPTCP skb extension is wasted. Detect these skbs and do not add skb extensions to them. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-28mptcp: Use full MPTCP-level disconnect state machineMat Martineau
RFC 8684 appendix D describes the connection state machine for MPTCP. This patch implements the DATA_FIN / DATA_ACK exchanges and MPTCP-level socket state changes described in that appendix, rather than simply sending DATA_FIN along with TCP FIN when disconnecting subflows. DATA_FIN is now sent and acknowledged before shutting down the subflows. Received DATA_FIN information (if not part of a data packet) is written to the MPTCP socket when the incoming DSS option is parsed by the subflow, and the MPTCP worker is scheduled to process the flag. DATA_FIN received as part of a full DSS mapping will be handled when the mapping is processed. The DATA_FIN is acknowledged by the worker if the reader is caught up. If there is still data to be moved to the MPTCP-level queue, ack_seq will be incremented to account for the DATA_FIN when it reaches the end of the stream and a DATA_ACK will be sent to the peer. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-28mptcp: Track received DATA_FIN sequence number and add related helpersMat Martineau
Incoming DATA_FIN headers need to propagate the presence of the DATA_FIN bit and the associated sequence number to the MPTCP layer, even when arriving on a bare ACK that does not get added to the receive queue. Add structure members to store the DATA_FIN information and helpers to set and check those values. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-28mptcp: Use MPTCP-level flag for sending DATA_FINMat Martineau
Since DATA_FIN information is the same for every subflow, store it only in the mptcp_sock. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-28mptcp: Allow DATA_FIN in headers without TCP FINMat Martineau
RFC 8684-compliant DATA_FIN needs to be sent and ack'd before subflows are closed with TCP FIN, so write DATA_FIN DSS headers whenever their transmission has been enabled by the MPTCP connection-level socket. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-23mptcp: explicitly track the fully established statusPaolo Abeni
Currently accepted msk sockets become established only after accept() returns the new sk to user-space. As MP_JOIN request are refused as per RFC spec on non fully established socket, the above causes mp_join self-tests instabilities. This change lets the msk entering the established status as soon as it receives the 3rd ack and propagates the first subflow fully established status on the msk socket. Finally we can change the subflow acceptance condition to take in account both the sock state and the msk fully established flag. 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>
2020-07-11Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
All conflicts seemed rather trivial, with some guidance from Saeed Mameed on the tc_ct.c one. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-07mptcp: fix DSS map generation on fin retransmissionPaolo Abeni
The RFC 8684 mandates that no-data DATA FIN packets should carry a DSS with 0 sequence number and data len equal to 1. Currently, on FIN retransmission we re-use the existing mapping; if the previous fin transmission was part of a partially acked data packet, we could end-up writing in the egress packet a non-compliant DSS. The above will be detected by a "Bad mapping" warning on the receiver side. This change addresses the issue explicitly checking for 0 len packet when adding the DATA_FIN option. Fixes: 6d0060f600ad ("mptcp: Write MPTCP DSS headers to outgoing data packets") Reported-by: syzbot+42a07faa5923cfaeb9c9@syzkaller.appspotmail.com Tested-by: Christoph Paasch <cpaasch@apple.com> Reviewed-by: Christoph Paasch <cpaasch@apple.com> 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>
2020-06-29net: mptcp: improve fallback to TCPDavide Caratti
Keep using MPTCP sockets and a use "dummy mapping" in case of fallback to regular TCP. When fallback is triggered, skip addition of the MPTCP option on send. Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/11 Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/22 Co-developed-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-22mptcp: drop sndr_key in mptcp_syn_optionsGeliang Tang
In RFC 8684, we don't need to send sndr_key in SYN package anymore, so drop it. Fixes: cc7972ea1932 ("mptcp: parse and emit MP_CAPABLE option according to v1 spec") Signed-off-by: Geliang Tang <geliangtang@gmail.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-08mptcp: bugfix for RM_ADDR option parsingGeliang Tang
In MPTCPOPT_RM_ADDR option parsing, the pointer "ptr" pointed to the "Subtype" octet, the pointer "ptr+1" pointed to the "Address ID" octet: +-------+-------+---------------+ |Subtype|(resvd)| Address ID | +-------+-------+---------------+ | | ptr ptr+1 We should set mp_opt->rm_id to the value of "ptr+1", not "ptr". This patch will fix this bug. Fixes: 3df523ab582c ("mptcp: Add ADD_ADDR handling") Signed-off-by: Geliang Tang <geliangtang@gmail.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
The MSCC bug fix in 'net' had to be slightly adjusted because the register accesses are done slightly differently in net-next. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-22mptcp: use untruncated hash in ADD_ADDR HMACTodd Malsbary
There is some ambiguity in the RFC as to whether the ADD_ADDR HMAC is the rightmost 64 bits of the entire hash or of the leftmost 160 bits of the hash. The intention, as clarified with the author of the RFC, is the entire hash. This change returns the entire hash from mptcp_crypto_hmac_sha (instead of only the first 160 bits), and moves any truncation/selection operation on the hash to the caller. Fixes: 12555a2d97e5 ("mptcp: use rightmost 64 bits in ADD_ADDR HMAC") Reviewed-by: Christoph Paasch <cpaasch@apple.com> Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Todd Malsbary <todd.malsbary@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-19mptcp: use rightmost 64 bits in ADD_ADDR HMACTodd Malsbary
This changes the HMAC used in the ADD_ADDR option from the leftmost 64 bits to the rightmost 64 bits as described in RFC 8684, section 3.4.1. This issue was discovered while adding support to packetdrill for the ADD_ADDR v1 option. Fixes: 3df523ab582c ("mptcp: Add ADD_ADDR handling") Signed-off-by: Todd Malsbary <todd.malsbary@linux.intel.com> Acked-by: Christoph Paasch <cpaasch@apple.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-16mptcp: Use 32-bit DATA_ACK when possibleChristoph Paasch
RFC8684 allows to send 32-bit DATA_ACKs as long as the peer is not sending 64-bit data-sequence numbers. The 64-bit DSN is only there for extreme scenarios when a very high throughput subflow is combined with a long-RTT subflow such that the high-throughput subflow wraps around the 32-bit sequence number space within an RTT of the high-RTT subflow. It is thus a rare scenario and we should try to use the 32-bit DATA_ACK instead as long as possible. It allows to reduce the TCP-option overhead by 4 bytes, thus makes space for an additional SACK-block. It also makes tcpdumps much easier to read when the DSN and DATA_ACK are both either 32 or 64-bit. Signed-off-by: Christoph Paasch <cpaasch@apple.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-30mptcp: initialize the data_fin field for mpc packetsPaolo Abeni
When parsing MPC+data packets we set the dss field, so we must also initialize the data_fin, or we can find stray value there. Fixes: 9a19371bf029 ("mptcp: fix data_fin handing in RX path") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-30mptcp: fix 'use_ack' option access.Paolo Abeni
The mentioned RX option field is initialized only for DSS packet, we must access it only if 'dss' is set too, or the subflow will end-up in a bad status, leading to RFC violations. Fixes: d22f4988ffec ("mptcp: process MP_CAPABLE data option") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-30mptcp: avoid a WARN on bad input.Paolo Abeni
Syzcaller has found a way to trigger the WARN_ON_ONCE condition in check_fully_established(). The root cause is a legit fallback to TCP scenario, so replace the WARN with a plain message on a more strict condition. Fixes: f296234c98a8 ("mptcp: Add handling of incoming MP_JOIN requests") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-30mptcp: move option parsing into mptcp_incoming_options()Paolo Abeni
The mptcp_options_received structure carries several per packet flags (mp_capable, mp_join, etc.). Such fields must be cleared on each packet, even on dropped ones or packet not carrying any MPTCP options, but the current mptcp code clears them only on TCP option reset. On several races/corner cases we end-up with stray bits in incoming options, leading to WARN_ON splats. e.g.: [ 171.164906] Bad mapping: ssn=32714 map_seq=1 map_data_len=32713 [ 171.165006] WARNING: CPU: 1 PID: 5026 at net/mptcp/subflow.c:533 warn_bad_map (linux-mptcp/net/mptcp/subflow.c:533 linux-mptcp/net/mptcp/subflow.c:531) [ 171.167632] Modules linked in: ip6_vti ip_vti ip_gre ipip sit tunnel4 ip_tunnel geneve ip6_udp_tunnel udp_tunnel macsec macvtap tap ipvlan macvlan 8021q garp mrp xfrm_interface veth netdevsim nlmon dummy team bonding vcan bridge stp llc ip6_gre gre ip6_tunnel tunnel6 tun binfmt_misc intel_rapl_msr intel_rapl_common rfkill kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel joydev virtio_balloon pcspkr i2c_piix4 sunrpc ip_tables xfs libcrc32c crc32c_intel serio_raw virtio_console ata_generic virtio_blk virtio_net net_failover failover ata_piix libata [ 171.199464] CPU: 1 PID: 5026 Comm: repro Not tainted 5.7.0-rc1.mptcp_f227fdf5d388+ #95 [ 171.200886] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-2.fc30 04/01/2014 [ 171.202546] RIP: 0010:warn_bad_map (linux-mptcp/net/mptcp/subflow.c:533 linux-mptcp/net/mptcp/subflow.c:531) [ 171.206537] Code: c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 1d 8b 55 3c 44 89 e6 48 c7 c7 20 51 13 95 e8 37 8b 22 fe <0f> 0b 48 83 c4 08 5b 5d 41 5c c3 89 4c 24 04 e8 db d6 94 fe 8b 4c [ 171.220473] RSP: 0018:ffffc90000150560 EFLAGS: 00010282 [ 171.221639] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 171.223108] RDX: 0000000000000000 RSI: 0000000000000008 RDI: fffff5200002a09e [ 171.224388] RBP: ffff8880aa6e3c00 R08: 0000000000000001 R09: fffffbfff2ec9955 [ 171.225706] R10: ffffffff9764caa7 R11: fffffbfff2ec9954 R12: 0000000000007fca [ 171.227211] R13: ffff8881066f4a7f R14: ffff8880aa6e3c00 R15: 0000000000000020 [ 171.228460] FS: 00007f8623719740(0000) GS:ffff88810be00000(0000) knlGS:0000000000000000 [ 171.230065] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 171.231303] CR2: 00007ffdab190a50 CR3: 00000001038ea006 CR4: 0000000000160ee0 [ 171.232586] Call Trace: [ 171.233109] <IRQ> [ 171.233531] get_mapping_status (linux-mptcp/net/mptcp/subflow.c:691) [ 171.234371] mptcp_subflow_data_available (linux-mptcp/net/mptcp/subflow.c:736 linux-mptcp/net/mptcp/subflow.c:832) [ 171.238181] subflow_state_change (linux-mptcp/net/mptcp/subflow.c:1085 (discriminator 1)) [ 171.239066] tcp_fin (linux-mptcp/net/ipv4/tcp_input.c:4217) [ 171.240123] tcp_data_queue (linux-mptcp/./include/linux/compiler.h:199 linux-mptcp/net/ipv4/tcp_input.c:4822) [ 171.245083] tcp_rcv_established (linux-mptcp/./include/linux/skbuff.h:1785 linux-mptcp/./include/net/tcp.h:1774 linux-mptcp/./include/net/tcp.h:1847 linux-mptcp/net/ipv4/tcp_input.c:5238 linux-mptcp/net/ipv4/tcp_input.c:5730) [ 171.254089] tcp_v4_rcv (linux-mptcp/./include/linux/spinlock.h:393 linux-mptcp/net/ipv4/tcp_ipv4.c:2009) [ 171.258969] ip_protocol_deliver_rcu (linux-mptcp/net/ipv4/ip_input.c:204 (discriminator 1)) [ 171.260214] ip_local_deliver_finish (linux-mptcp/./include/linux/rcupdate.h:651 linux-mptcp/net/ipv4/ip_input.c:232) [ 171.261389] ip_local_deliver (linux-mptcp/./include/linux/netfilter.h:307 linux-mptcp/./include/linux/netfilter.h:301 linux-mptcp/net/ipv4/ip_input.c:252) [ 171.265884] ip_rcv (linux-mptcp/./include/linux/netfilter.h:307 linux-mptcp/./include/linux/netfilter.h:301 linux-mptcp/net/ipv4/ip_input.c:539) [ 171.273666] process_backlog (linux-mptcp/./include/linux/rcupdate.h:651 linux-mptcp/net/core/dev.c:6135) [ 171.275328] net_rx_action (linux-mptcp/net/core/dev.c:6572 linux-mptcp/net/core/dev.c:6640) [ 171.280472] __do_softirq (linux-mptcp/./arch/x86/include/asm/jump_label.h:25 linux-mptcp/./include/linux/jump_label.h:200 linux-mptcp/./include/trace/events/irq.h:142 linux-mptcp/kernel/softirq.c:293) [ 171.281379] do_softirq_own_stack (linux-mptcp/arch/x86/entry/entry_64.S:1083) [ 171.282358] </IRQ> We could address the issue clearing explicitly the relevant fields in several places - tcp_parse_option, tcp_fast_parse_options, possibly others. Instead we move the MPTCP option parsing into the already existing mptcp ingress hook, so that we need to clear the fields in a single place. This allows us dropping an MPTCP hook from the TCP code and removing the quite large mptcp_options_received from the tcp_sock struct. On the flip side, the MPTCP sockets will traverse the option space twice (in tcp_parse_option() and in mptcp_incoming_options(). That looks acceptable: we already do that for syn and 3rd ack packets, plain TCP socket will benefit from it, and even MPTCP sockets will experience better code locality, reducing the jumps between TCP and MPTCP code. v1 -> v2: - rebased on current '-net' tree Fixes: 648ef4b88673 ("mptcp: Implement MPTCP receive path") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-30mptcp: consolidate synack processing.Paolo Abeni
Currently the MPTCP code uses 2 hooks to process syn-ack packets, mptcp_rcv_synsent() and the sk_rx_dst_set() callback. We can drop the first, moving the relevant code into the latter, reducing the hooking into the TCP code. This is also needed by the next patch. v1 -> v2: - use local tcp sock ptr instead of casting the sk variable several times - DaveM Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-22mptcp: fix data_fin handing in RX pathPaolo Abeni
The data fin flag is set only via a DSS option, but mptcp_incoming_options() copies it unconditionally from the provided RX options. Since we do not clear all the mptcp sock RX options in a socket free/alloc cycle, we can end-up with a stray data_fin value while parsing e.g. MPC packets. That would lead to mapping data corruption and will trigger a few WARN_ON() in the RX path. Instead of adding a costly memset(), fetch the data_fin flag only for DSS packets - when we always explicitly initialize such bit at option parsing time. Fixes: 648ef4b88673 ("mptcp: Implement MPTCP receive path") 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>
2020-04-03mptcp: add some missing pr_fmt definesGeliang Tang
Some of the mptcp logs didn't print out the format string: [ 185.651493] DSS [ 185.651494] data_fin=0 dsn64=0 use_map=0 ack64=1 use_ack=1 [ 185.651494] data_ack=13792750332298763796 [ 185.651495] MPTCP: msk=00000000c4b81cfc ssk=000000009743af53 data_avail=0 skb=0000000063dc595d [ 185.651495] MPTCP: msk=00000000c4b81cfc ssk=000000009743af53 status=0 [ 185.651495] MPTCP: msk ack_seq=9bbc894565aa2f9a subflow ack_seq=9bbc894565aa2f9a [ 185.651496] MPTCP: msk=00000000c4b81cfc ssk=000000009743af53 data_avail=1 skb=0000000012e809e1 So this patch added these missing pr_fmt defines. Then we can get the same format string "MPTCP" in all mptcp logs like this: [ 142.795829] MPTCP: DSS [ 142.795829] MPTCP: data_fin=0 dsn64=0 use_map=0 ack64=1 use_ack=1 [ 142.795829] MPTCP: data_ack=8089704603109242421 [ 142.795830] MPTCP: msk=00000000133a24e0 ssk=000000002e508c64 data_avail=0 skb=00000000d5f230df [ 142.795830] MPTCP: msk=00000000133a24e0 ssk=000000002e508c64 status=0 [ 142.795831] MPTCP: msk ack_seq=66790290f1199d9b subflow ack_seq=66790290f1199d9b [ 142.795831] MPTCP: msk=00000000133a24e0 ssk=000000002e508c64 data_avail=1 skb=00000000de5aca2e Signed-off-by: Geliang Tang <geliangtang@gmail.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-29mptcp: introduce MPTCP retransmission timerPaolo Abeni
The timer will be used to schedule retransmission. It's frequency is based on the current subflow RTO estimation and is reset on every una_seq update The timer is clearer for good by __mptcp_clear_xmit() Also clean MPTCP rtx queue before each transmission. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-29mptcp: update per unacked sequence on pkt receptionPaolo Abeni
So that we keep per unacked sequence number consistent; since we update per msk data, use an atomic64 cmpxchg() to protect against concurrent updates from multiple subflows. Initialize the snd_una at connect()/accept() time. Co-developed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-29mptcp: Add handling of outgoing MP_JOIN requestsPeter Krystad
Subflow creation may be initiated by the path manager when the primary connection is fully established and a remote address has been received via ADD_ADDR. Create an in-kernel sock and use kernel_connect() to initiate connection. Passive sockets can't acquire the mptcp socket lock at subflow creation time, so an additional list protected by a new spinlock is used to track the MPJ subflows. Such list is spliced into conn_list tail every time the msk socket lock is acquired, so that it will not interfere with data flow on the original connection. Data flow and connection failover not addressed by this commit. 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> Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> 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>
2020-03-29mptcp: Add handling of incoming MP_JOIN requestsPeter Krystad
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>
2020-03-29mptcp: Add path manager interfacePeter Krystad
Add enough of a path manager interface to allow sending of ADD_ADDR when an incoming MPTCP connection is created. Capable of sending only a single IPv4 ADD_ADDR option. The 'pm_data' element of the connection sock will need to be expanded to handle multiple interfaces and IPv6. Partial processing of the incoming ADD_ADDR is included so the path manager notification of that event happens at the proper time, which involves validating the incoming address information. This is a skeleton interface definition for events generated by MPTCP. Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> 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> Co-developed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Peter Krystad <peter.krystad@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-29mptcp: Add ADD_ADDR handlingPeter Krystad
Add handling for sending and receiving the ADD_ADDR, ADD_ADDR6, and RM_ADDR suboptions. Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> 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>
2020-03-21mptcp: Remove set but not used variable 'can_ack'YueHaibing
Fixes gcc '-Wunused-but-set-variable' warning: net/mptcp/options.c: In function 'mptcp_established_options_dss': net/mptcp/options.c:338:7: warning: variable 'can_ack' set but not used [-Wunused-but-set-variable] commit dc093db5cc05 ("mptcp: drop unneeded checks") leave behind this unused, remove it. Signed-off-by: YueHaibing <yuehaibing@huawei.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-19mptcp: rename fourth ack fieldPaolo Abeni
The name is misleading, it actually tracks the 'fully established' status. 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>
2020-03-15mptcp: drop unneeded checksPaolo Abeni
After the previous patch subflow->conn is always != NULL and is never changed. We can drop a bunch of now unneeded checks. v1 -> v2: - rebased on top of commit 2398e3991bda ("mptcp: always include dack if possible.") 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>
2020-03-12Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Minor overlapping changes, nothing serious. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-05mptcp: always include dack if possible.Paolo Abeni
Currently passive MPTCP socket can skip including the DACK option - if the peer sends data before accept() completes. The above happens because the msk 'can_ack' flag is set only after the accept() call. Such missing DACK option may cause - as per RFC spec - unwanted fallback to TCP. This change addresses the issue using the key material available in the current subflow, if any, to create a suitable dack option when msk ack seq is not yet available. v1 -> v2: - adavance the generated ack after the initial MPC packet Fixes: d22f4988ffec ("mptcp: process MP_CAPABLE data option") 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>
2020-03-03mptcp: Only send DATA_FIN with final mappingMat Martineau
When a DATA_FIN is sent in a MPTCP DSS option that contains a data mapping, the DATA_FIN consumes one byte of space in the mapping. In this case, the DATA_FIN should only be included in the DSS option if its sequence number aligns with the end of the mapped data. Otherwise the subflow can send an incorrect implicit sequence number for the DATA_FIN, and the DATA_ACK for that sequence number would not close the MPTCP-level connection correctly. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-03mptcp: Use per-subflow storage for DATA_FIN sequence numberMat Martineau
Instead of reading the MPTCP-level sequence number when sending DATA_FIN, store the data in the subflow so it can be safely accessed when the subflow TCP headers are written to the packet without the MPTCP-level lock held. This also allows the MPTCP-level socket to close individual subflows without closing the MPTCP connection. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-24mptcp: process MP_CAPABLE data optionChristoph Paasch
This patch implements the handling of MP_CAPABLE + data option, as per RFC 6824 bis / RFC 8684: MPTCP v1. On the server side we can receive the remote key after that the connection is established. We need to explicitly track the 'missing remote key' status and avoid emitting a mptcp ack until we get such info. When a late/retransmitted/OoO pkt carrying MP_CAPABLE[+data] option is received, we have to propagate the mptcp seq number info to the msk socket. To avoid ABBA locking issue, explicitly check for that in recvmsg(), where we own msk and subflow sock locks. The above also means that an established mp_capable subflow - still waiting for the remote key - can be 'downgraded' to plain TCP. Such change could potentially block a reader waiting for new data forever - as they hook to msk, while later wake-up after the downgrade will be on subflow only. The above issue is not handled here, we likely have to get rid of msk->fallback to handle that cleanly. Signed-off-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-24mptcp: parse and emit MP_CAPABLE option according to v1 specChristoph Paasch
This implements MP_CAPABLE options parsing and writing according to RFC 6824 bis / RFC 8684: MPTCP v1. Local key is sent on syn/ack, and both keys are sent on 3rd ack. MP_CAPABLE messages len are updated accordingly. We need the skbuff to correctly emit the above, so we push the skbuff struct as an argument all the way from tcp code to the relevant mptcp callbacks. When processing incoming MP_CAPABLE + data, build a full blown DSS-like map info, to simplify later processing. On child socket creation, we need to record the remote key, if available. Signed-off-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-24mptcp: move from sha1 (v0) to sha256 (v1)Paolo Abeni
For simplicity's sake use directly sha256 primitives (and pull them as a required build dep). Add optional, boot-time self-tests for the hmac function. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-24mptcp: Implement MPTCP receive pathMat Martineau
Parses incoming DSS options and populates outgoing MPTCP ACK fields. MPTCP fields are parsed from the TCP option header and placed in an skb extension, allowing the upper MPTCP layer to access MPTCP options after the skb has gone through the TCP stack. The subflow implements its own data_ready() ops, which ensures that the pending data is in sequence - according to MPTCP seq number - dropping out-of-seq skbs. The DATA_READY bit flag is set if this is the case. This allows the MPTCP socket layer to determine if more data is available without having to consult the individual subflows. It additionally validates the current mapping and propagates EoF events to the connection socket. Co-developed-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Co-developed-by: Peter Krystad <peter.krystad@linux.intel.com> Signed-off-by: Peter Krystad <peter.krystad@linux.intel.com> Co-developed-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Co-developed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-24mptcp: Write MPTCP DSS headers to outgoing data packetsMat Martineau
Per-packet metadata required to write the MPTCP DSS option is written to the skb_ext area. One write to the socket may contain more than one packet of data, which is copied to page fragments and mapped in to MPTCP DSS segments with size determined by the available page fragments and the maximum mapping length allowed by the MPTCP specification. If do_tcp_sendpages() splits a DSS segment in to multiple skbs, that's ok - the later skbs can either have duplicated DSS mapping information or none at all, and the receiver can handle that. The current implementation uses the subflow frag cache and tcp sendpages to avoid excessive code duplication. More work is required to ensure that it works correctly under memory pressure and to support MPTCP-level retransmissions. The MPTCP DSS checksum is not yet implemented. Co-developed-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Co-developed-by: Peter Krystad <peter.krystad@linux.intel.com> Signed-off-by: Peter Krystad <peter.krystad@linux.intel.com> Co-developed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-24mptcp: Handle MP_CAPABLE options for outgoing connectionsPeter Krystad
Add hooks to tcp_output.c to add MP_CAPABLE to an outgoing SYN request, to capture the MP_CAPABLE in the received SYN-ACK, to add MP_CAPABLE to the final ACK of the three-way handshake. Use the .sk_rx_dst_set() handler in the subflow proto to capture when the responding SYN-ACK is received and notify the MPTCP connection layer. Co-developed-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Co-developed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Florian Westphal <fw@strlen.de> 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>
2020-01-24mptcp: Handle MPTCP TCP optionsPeter Krystad
Add hooks to parse and format the MP_CAPABLE option. This option is handled according to MPTCP version 0 (RFC6824). MPTCP version 1 MP_CAPABLE (RFC6824bis/RFC8684) will be added later in coordination with related code changes. Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Co-developed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Florian Westphal <fw@strlen.de> Co-developed-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: Davide Caratti <dcaratti@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>