Commit Graph

383 Commits

Author SHA1 Message Date
Jakub Kicinski b89fec54fd tls: rx: wrap decrypt params in a struct
The max size of iv + aad + tail is 22B. That's smaller
than a single sg entry (32B). Don't bother with the
memory packing, just create a struct which holds the
max size of those members.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-08 18:38:45 -07:00
Jakub Kicinski 50a07aa531 tls: rx: always allocate max possible aad size for decrypt
AAD size is either 5 or 13. Really no point complicating
the code for the 8B of difference. This will also let us
turn the chunked up buffer into a sane struct.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-08 18:38:45 -07:00
Jakub Kicinski 83ec88d81a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-07 12:07:37 -07:00
Gal Pressman a069a90554 Revert "tls: rx: move counting TlsDecryptErrors for sync"
This reverts commit 284b4d93da.
When using TLS device offload and coming from tls_device_reencrypt()
flow, -EBADMSG error in tls_do_decryption() should not be counted
towards the TLSTlsDecryptError counter.

Move the counter increase back to the decrypt_internal() call site in
decrypt_skb_update().
This also fixes an issue where:
	if (n_sgin < 1)
		return -EBADMSG;

Errors in decrypt_internal() were not counted after the cited patch.

Fixes: 284b4d93da ("tls: rx: move counting TlsDecryptErrors for sync")
Cc: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Gal Pressman <gal@nvidia.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-06 13:10:59 +01:00
Jakub Kicinski c46b01839f tls: rx: periodically flush socket backlog
We continuously hold the socket lock during large reads and writes.
This may inflate RTT and negatively impact TCP performance.
Flush the backlog periodically. I tried to pick a flush period (128kB)
which gives significant benefit but the max Bps rate is not yet visibly
impacted.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-06 12:56:35 +01:00
Jakub Kicinski 88527790c0 tls: rx: add sockopt for enabling optimistic decrypt with TLS 1.3
Since optimisitic decrypt may add extra load in case of retries
require socket owner to explicitly opt-in.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-06 12:56:35 +01:00
Jakub Kicinski ce61327ce9 tls: rx: support optimistic decrypt to user buffer with TLS 1.3
We currently don't support decrypt to user buffer with TLS 1.3
because we don't know the record type and how much padding
record contains before decryption. In practice data records
are by far most common and padding gets used rarely so
we can assume data record, no padding, and if we find out
that wasn't the case - retry the crypto in place (decrypt
to skb).

To safeguard from user overwriting content type and padding
before we can check it attach a 1B sg entry where last byte
of the record will land.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-06 12:56:35 +01:00
Jakub Kicinski 603380f54f tls: rx: don't include tail size in data_len
To make future patches easier to review make data_len
contain the length of the data, without the tail.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-06 12:56:35 +01:00
Eric Dumazet 504148fedb net: add skb_[inner_]tcp_all_headers helpers
Most drivers use "skb_transport_offset(skb) + tcp_hdrlen(skb)"
to compute headers length for a TCP packet, but others
use more convoluted (but equivalent) ways.

Add skb_tcp_all_headers() and skb_inner_tcp_all_headers()
helpers to harmonize this a bit.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-02 16:22:25 +01:00
Jakub Kicinski e34a07c0ae sock: redo the psock vs ULP protection check
Commit 8a59f9d1e3 ("sock: Introduce sk->sk_prot->psock_update_sk_prot()")
has moved the inet_csk_has_ulp(sk) check from sk_psock_init() to
the new tcp_bpf_update_proto() function. I'm guessing that this
was done to allow creating psocks for non-inet sockets.

Unfortunately the destruction path for psock includes the ULP
unwind, so we need to fail the sk_psock_init() itself.
Otherwise if ULP is already present we'll notice that later,
and call tcp_update_ulp() with the sk_proto of the ULP
itself, which will most likely result in the ULP looping
its callbacks.

Fixes: 8a59f9d1e3 ("sock: Introduce sk->sk_prot->psock_update_sk_prot()")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Tested-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/r/20220620191353.1184629-2-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-06-23 10:08:30 +02:00
Jakub Kicinski 1b205d948f Revert "net/tls: fix tls_sk_proto_close executed repeatedly"
This reverts commit 69135c572d.

This commit was just papering over the issue, ULP should not
get ->update() called with its own sk_prot. Each ULP would
need to add this check.

Fixes: 69135c572d ("net/tls: fix tls_sk_proto_close executed repeatedly")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20220620191353.1184629-1-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-06-23 10:08:30 +02:00
Ziyang Xuan 69135c572d net/tls: fix tls_sk_proto_close executed repeatedly
After setting the sock ktls, update ctx->sk_proto to sock->sk_prot by
tls_update(), so now ctx->sk_proto->close is tls_sk_proto_close(). When
close the sock, tls_sk_proto_close() is called for sock->sk_prot->close
is tls_sk_proto_close(). But ctx->sk_proto->close() will be executed later
in tls_sk_proto_close(). Thus tls_sk_proto_close() executed repeatedly
occurred. That will trigger the following bug.

=================================================================
KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
RIP: 0010:tls_sk_proto_close+0xd8/0xaf0 net/tls/tls_main.c:306
Call Trace:
 <TASK>
 tls_sk_proto_close+0x356/0xaf0 net/tls/tls_main.c:329
 inet_release+0x12e/0x280 net/ipv4/af_inet.c:428
 __sock_release+0xcd/0x280 net/socket.c:650
 sock_close+0x18/0x20 net/socket.c:1365

Updating a proto which is same with sock->sk_prot is incorrect. Add proto
and sock->sk_prot equality check at the head of tls_update() to fix it.

Fixes: 95fa145479 ("bpf: sockmap/tls, close can race with map free")
Reported-by: syzbot+29c3c12f3214b85ad081@syzkaller.appspotmail.com
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-06-20 10:01:52 +01:00
Maxim Mikityanskiy b489a6e587 tls: Rename TLS_INFO_ZC_SENDFILE to TLS_INFO_ZC_TX
To embrace possible future optimizations of TLS, rename zerocopy
sendfile definitions to more generic ones:

* setsockopt: TLS_TX_ZEROCOPY_SENDFILE- > TLS_TX_ZEROCOPY_RO
* sock_diag: TLS_INFO_ZC_SENDFILE -> TLS_INFO_ZC_RO_TX

RO stands for readonly and emphasizes that the application shouldn't
modify the data being transmitted with zerocopy to avoid potential
disconnection.

Fixes: c1318b39c7 ("tls: Add opt-in zerocopy mode of sendfile()")
Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Link: https://lore.kernel.org/r/20220608153425.3151146-1-maximmi@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-09 21:51:57 -07:00
Jakub Kicinski 1c2133114d net: tls: fix messing up lists when bpf enabled
Artem points out that skb may try to take over the skb and
queue it to its own list. Unlink the skb before calling out.

Fixes: b1a2c17863 ("tls: rx: clear ctx->recv_pkt earlier")
Reported-by: Artem Savkov <asavkov@redhat.com>
Tested-by: Artem Savkov <asavkov@redhat.com>
Link: https://lore.kernel.org/r/20220518205644.2059468-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-19 17:55:06 -07:00
Boris Pismenny c1318b39c7 tls: Add opt-in zerocopy mode of sendfile()
TLS device offload copies sendfile data to a bounce buffer before
transmitting. It allows to maintain the valid MAC on TLS records when
the file contents change and a part of TLS record has to be
retransmitted on TCP level.

In many common use cases (like serving static files over HTTPS) the file
contents are not changed on the fly. In many use cases breaking the
connection is totally acceptable if the file is changed during
transmission, because it would be received corrupted in any case.

This commit allows to optimize performance for such use cases to
providing a new optional mode of TLS sendfile(), in which the extra copy
is skipped. Removing this copy improves performance significantly, as
TLS and TCP sendfile perform the same operations, and the only overhead
is TLS header/trailer insertion.

The new mode can only be enabled with the new socket option named
TLS_TX_ZEROCOPY_SENDFILE on per-socket basis. It preserves backwards
compatibility with existing applications that rely on the copying
behavior.

The new mode is safe, meaning that unsolicited modifications of the file
being sent can't break integrity of the kernel. The worst thing that can
happen is sending a corrupted TLS record, which is in any case not
forbidden when using regular TCP sockets.

Sockets other than TLS device offload are not affected by the new socket
option. The actual status of zerocopy sendfile can be queried with
sock_diag.

Performance numbers in a single-core test with 24 HTTPS streams on
nginx, under 100% CPU load:

* non-zerocopy: 33.6 Gbit/s
* zerocopy: 79.92 Gbit/s

CPU: Intel(R) Xeon(R) Platinum 8380 CPU @ 2.30GHz

Signed-off-by: Boris Pismenny <borisp@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20220518092731.1243494-1-maximmi@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-05-19 12:14:11 +02:00
Jakub Kicinski 9b19e57a3c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Build issue in drivers/net/ethernet/sfc/ptp.c
  54fccfdd7c ("sfc: efx_default_channel_type APIs can be static")
  49e6123c65 ("net: sfc: fix memory leak due to ptp channel")
https://lore.kernel.org/all/20220510130556.52598fe2@canb.auug.org.au/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-12 16:15:30 -07:00
Maxim Mikityanskiy 3740651bf7 tls: Fix context leak on tls_device_down
The commit cited below claims to fix a use-after-free condition after
tls_device_down. Apparently, the description wasn't fully accurate. The
context stayed alive, but ctx->netdev became NULL, and the offload was
torn down without a proper fallback, so a bug was present, but a
different kind of bug.

Due to misunderstanding of the issue, the original patch dropped the
refcount_dec_and_test line for the context to avoid the alleged
premature deallocation. That line has to be restored, because it matches
the refcount_inc_not_zero from the same function, otherwise the contexts
that survived tls_device_down are leaked.

This patch fixes the described issue by restoring refcount_dec_and_test.
After this change, there is no leak anymore, and the fallback to
software kTLS still works.

Fixes: c55dcdd435 ("net/tls: Fix use-after-free after the TLS device goes down and up")
Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://lore.kernel.org/r/20220512091830.678684-1-maximmi@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-12 10:01:36 -07:00
Jakub Kicinski 0e55546b18 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
include/linux/netdevice.h
net/core/dev.c
  6510ea973d ("net: Use this_cpu_inc() to increment net->core_stats")
  794c24e992 ("net-core: rx_otherhost_dropped to core_stats")
https://lore.kernel.org/all/20220428111903.5f4304e0@canb.auug.org.au/

drivers/net/wan/cosa.c
  d48fea8401 ("net: cosa: fix error check return value of register_chrdev()")
  89fbca3307 ("net: wan: remove support for COSA and SRP synchronous serial boards")
https://lore.kernel.org/all/20220428112130.1f689e5e@canb.auug.org.au/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-04-28 13:02:01 -07:00
Maxim Mikityanskiy a0df71948e tls: Skip tls_append_frag on zero copy size
Calling tls_append_frag when max_open_record_len == record->len might
add an empty fragment to the TLS record if the call happens to be on the
page boundary. Normally tls_append_frag coalesces the zero-sized
fragment to the previous one, but not if it's on page boundary.

If a resync happens then, the mlx5 driver posts dump WQEs in
tx_post_resync_dump, and the empty fragment may become a data segment
with byte_count == 0, which will confuse the NIC and lead to a CQE
error.

This commit fixes the described issue by skipping tls_append_frag on
zero size to avoid adding empty fragments. The fix is not in the driver,
because an empty fragment is hardly the desired behavior.

Fixes: e8f6979981 ("net/tls: Add generic NIC offload infrastructure")
Signed-off-by: Maxim Mikityanskiy <maximmi@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://lore.kernel.org/r/20220426154949.159055-1-maximmi@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-04-27 15:25:20 -07:00
Jakub Kicinski c706b2b5ed net: tls: fix async vs NIC crypto offload
When NIC takes care of crypto (or the record has already
been decrypted) we forget to update darg->async. ->async
is supposed to mean whether record is async capable on
input and whether record has been queued for async crypto
on output.

Reported-by: Gal Pressman <gal@nvidia.com>
Fixes: 3547a1f9d9 ("tls: rx: use async as an in-out argument")
Tested-by: Gal Pressman <gal@nvidia.com>
Link: https://lore.kernel.org/r/20220425233309.344858-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-04-26 17:08:49 -07:00
Eric Dumazet 68822bdf76 net: generalize skb freeing deferral to per-cpu lists
Logic added in commit f35f821935 ("tcp: defer skb freeing after socket
lock is released") helped bulk TCP flows to move the cost of skbs
frees outside of critical section where socket lock was held.

But for RPC traffic, or hosts with RFS enabled, the solution is far from
being ideal.

For RPC traffic, recvmsg() has to return to user space right after
skb payload has been consumed, meaning that BH handler has no chance
to pick the skb before recvmsg() thread. This issue is more visible
with BIG TCP, as more RPC fit one skb.

For RFS, even if BH handler picks the skbs, they are still picked
from the cpu on which user thread is running.

Ideally, it is better to free the skbs (and associated page frags)
on the cpu that originally allocated them.

This patch removes the per socket anchor (sk->defer_list) and
instead uses a per-cpu list, which will hold more skbs per round.

This new per-cpu list is drained at the end of net_action_rx(),
after incoming packets have been processed, to lower latencies.

In normal conditions, skbs are added to the per-cpu list with
no further action. In the (unlikely) cases where the cpu does not
run net_action_rx() handler fast enough, we use an IPI to raise
NET_RX_SOFTIRQ on the remote cpu.

Also, we do not bother draining the per-cpu list from dev_cpu_dead()
This is because skbs in this list have no requirement on how fast
they should be freed.

Note that we can add in the future a small per-cpu cache
if we see any contention on sd->defer_lock.

Tested on a pair of hosts with 100Gbit NIC, RFS enabled,
and /proc/sys/net/ipv4/tcp_rmem[2] tuned to 16MB to work around
page recycling strategy used by NIC driver (its page pool capacity
being too small compared to number of skbs/pages held in sockets
receive queues)

Note that this tuning was only done to demonstrate worse
conditions for skb freeing for this particular test.
These conditions can happen in more general production workload.

10 runs of one TCP_STREAM flow

Before:
Average throughput: 49685 Mbit.

Kernel profiles on cpu running user thread recvmsg() show high cost for
skb freeing related functions (*)

    57.81%  [kernel]       [k] copy_user_enhanced_fast_string
(*) 12.87%  [kernel]       [k] skb_release_data
(*)  4.25%  [kernel]       [k] __free_one_page
(*)  3.57%  [kernel]       [k] __list_del_entry_valid
     1.85%  [kernel]       [k] __netif_receive_skb_core
     1.60%  [kernel]       [k] __skb_datagram_iter
(*)  1.59%  [kernel]       [k] free_unref_page_commit
(*)  1.16%  [kernel]       [k] __slab_free
     1.16%  [kernel]       [k] _copy_to_iter
(*)  1.01%  [kernel]       [k] kfree
(*)  0.88%  [kernel]       [k] free_unref_page
     0.57%  [kernel]       [k] ip6_rcv_core
     0.55%  [kernel]       [k] ip6t_do_table
     0.54%  [kernel]       [k] flush_smp_call_function_queue
(*)  0.54%  [kernel]       [k] free_pcppages_bulk
     0.51%  [kernel]       [k] llist_reverse_order
     0.38%  [kernel]       [k] process_backlog
(*)  0.38%  [kernel]       [k] free_pcp_prepare
     0.37%  [kernel]       [k] tcp_recvmsg_locked
(*)  0.37%  [kernel]       [k] __list_add_valid
     0.34%  [kernel]       [k] sock_rfree
     0.34%  [kernel]       [k] _raw_spin_lock_irq
(*)  0.33%  [kernel]       [k] __page_cache_release
     0.33%  [kernel]       [k] tcp_v6_rcv
(*)  0.33%  [kernel]       [k] __put_page
(*)  0.29%  [kernel]       [k] __mod_zone_page_state
     0.27%  [kernel]       [k] _raw_spin_lock

After patch:
Average throughput: 73076 Mbit.

Kernel profiles on cpu running user thread recvmsg() looks better:

    81.35%  [kernel]       [k] copy_user_enhanced_fast_string
     1.95%  [kernel]       [k] _copy_to_iter
     1.95%  [kernel]       [k] __skb_datagram_iter
     1.27%  [kernel]       [k] __netif_receive_skb_core
     1.03%  [kernel]       [k] ip6t_do_table
     0.60%  [kernel]       [k] sock_rfree
     0.50%  [kernel]       [k] tcp_v6_rcv
     0.47%  [kernel]       [k] ip6_rcv_core
     0.45%  [kernel]       [k] read_tsc
     0.44%  [kernel]       [k] _raw_spin_lock_irqsave
     0.37%  [kernel]       [k] _raw_spin_lock
     0.37%  [kernel]       [k] native_irq_return_iret
     0.33%  [kernel]       [k] __inet6_lookup_established
     0.31%  [kernel]       [k] ip6_protocol_deliver_rcu
     0.29%  [kernel]       [k] tcp_rcv_established
     0.29%  [kernel]       [k] llist_reverse_order

v2: kdoc issue (kernel bots)
    do not defer if (alloc_cpu == smp_processor_id()) (Paolo)
    replace the sk_buff_head with a single-linked list (Jakub)
    add a READ_ONCE()/WRITE_ONCE() for the lockless read of sd->defer_list

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20220422201237.416238-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-04-26 17:05:59 -07:00
Jakub Kicinski a4ae58cdb6 tls: rx: only copy IV from the packet for TLS 1.2
TLS 1.3 and ChaChaPoly don't carry IV in the packet.
The code before this change would copy out iv_size
worth of whatever followed the TLS header in the packet
and then for TLS 1.3 | ChaCha overwrite that with
the sequence number. Waste of cycles especially
with TLS 1.2 being close to dead and TLS 1.3 being
the common case.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-13 11:45:39 +01:00
Jakub Kicinski f7d45f4b52 tls: rx: use MAX_IV_SIZE for allocations
IVs are 8 or 16 bytes, no point reading out the exact value
for quantities this small.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-13 11:45:39 +01:00
Jakub Kicinski 3547a1f9d9 tls: rx: use async as an in-out argument
Propagating EINPROGRESS thru multiple layers of functions is
error prone. Use darg->async as an in/out argument, like we
use darg->zc today. On input it tells the code if async is
allowed, on output if it took place.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-13 11:45:39 +01:00
Jakub Kicinski f314bfee81 tls: rx: return the already-copied data on crypto error
async crypto handler will report the socket error no need
to report it again. We can, however, let the data we already
copied be reported to user space but we need to make sure
the error will be reported next time around.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-13 11:45:39 +01:00
Jakub Kicinski 4dcdd971b9 tls: rx: treat process_rx_list() errors as transient
process_rx_list() only fails if it can't copy data to user
space. There is no point recording the error onto sk->sk_err
or giving up on the data which was read partially. Treat
the return value like a normal socket partial read.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-13 11:45:39 +01:00
Jakub Kicinski 1c699ffa48 tls: rx: assume crypto always calls our callback
If crypto didn't always invoke our callback for async
we'd not be clearing skb->sk and would crash in the
skb core when freeing it. This if must be dead code.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-13 11:45:39 +01:00
Jakub Kicinski 72f3ad73bc tls: rx: don't handle TLS 1.3 in the async crypto callback
Async crypto never worked with TLS 1.3 and was explicitly disabled in
commit 8497ded2d1 ("net/tls: Disable async decrytion for tls1.3").
There's no need for us to handle TLS 1.3 padding in the async cb.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-13 11:45:39 +01:00
Jakub Kicinski 284b4d93da tls: rx: move counting TlsDecryptErrors for sync
Move counting TlsDecryptErrors to tls_do_decryption()
where differences between sync and async crypto are
reconciled.

No functional changes, this code just always gave
me a pause.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-13 11:45:39 +01:00
Jakub Kicinski 0775639ce1 tls: rx: reuse leave_on_list label for psock
The code is identical, we can save a few LoC.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-13 11:45:39 +01:00
Jakub Kicinski a30295c454 tls: rx: consistently use unlocked accessors for rx_list
rx_list is protected by the socket lock, no need to take
the built-in spin lock on accesses.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-13 11:45:39 +01:00
Oliver Hartkopp ec095263a9 net: remove noblock parameter from recvmsg() entities
The internal recvmsg() functions have two parameters 'flags' and 'noblock'
that were merged inside skb_recv_datagram(). As a follow up patch to commit
f4b41f062c ("net: remove noblock parameter from skb_recv_datagram()")
this patch removes the separate 'noblock' parameter for recvmsg().

Analogue to the referenced patch for skb_recv_datagram() the 'flags' and
'noblock' parameters are unnecessarily split up with e.g.

err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
                           flags & ~MSG_DONTWAIT, &addr_len);

or in

err = INDIRECT_CALL_2(sk->sk_prot->recvmsg, tcp_recvmsg, udp_recvmsg,
                      sk, msg, size, flags & MSG_DONTWAIT,
                      flags & ~MSG_DONTWAIT, &addr_len);

instead of simply using only flags all the time and check for MSG_DONTWAIT
where needed (to preserve for the formerly separated no(n)block condition).

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20220411124955.154876-1-socketcan@hartkopp.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-04-12 15:00:25 +02:00
Jakub Kicinski f940b6efb1 tls: rx: jump out for cases which need to leave skb on list
The current invese logic is harder to follow (and adds extra
tests to the fast path). We have to enumerate all cases which
need to keep the skb before consuming it. It's simpler to
jump out of the full record flow as we detect those cases.

This makes it clear that partial consumption and peek can
only reach end of the function thru the !zc case so move
the code up there.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-10 17:32:12 +01:00
Jakub Kicinski b1a2c17863 tls: rx: clear ctx->recv_pkt earlier
Whatever we do in the loop the skb should not remain on as
ctx->recv_pkt afterwards. We can clear that pointer and
restart strparser earlier.

This adds overhead of extra linking and unlinking to rx_list
but that's not large (upcoming change will switch to unlocked
skb list operations).

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-10 17:32:12 +01:00
Jakub Kicinski 465ea73535 tls: rx: inline consuming the skb at the end of the loop
tls_sw_advance_skb() always consumes the skb at the end of the loop.

To fall here the following must be true:

 !async && !is_peek && !retain_skb
   retain_skb => !zc && rxm->full_len > len
     # but non-full record implies !zc, so above can be simplified as
   retain_skb => rxm->full_len > len

 !async && !is_peek && !(rxm->full_len > len)
 !async && !is_peek && rxm->full_len <= len

tls_sw_advance_skb() returns false if len < rxm->full_len
which can't be true given conditions above.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-10 17:32:12 +01:00
Jakub Kicinski ba13609df1 tls: rx: pull most of zc check out of the loop
Most of the conditions deciding if zero-copy can be used
do not change throughout the iterations, so pre-calculate
them.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-10 17:32:11 +01:00
Jakub Kicinski 7da18bcc5e tls: rx: don't track the async count
We track both if the last record was handled by async crypto
and how many records were async. This is not necessary. We
implicitly assume once crypto goes async it will stay that
way, otherwise we'd reorder records. So just track if we're
in async mode, the exact number of records is not necessary.

This change also forces us into "async" mode more consistently
in case crypto ever decided to interleave async and sync.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-10 17:32:11 +01:00
Jakub Kicinski fc8da80f99 tls: rx: don't handle async in tls_sw_advance_skb()
tls_sw_advance_skb() caters to the async case when skb argument
is NULL. In that case it simply unpauses the strparser.

These are surprising semantics to a person reading the code,
and result in higher LoC, so inline the __strp_unpause and
only call tls_sw_advance_skb() when we actually move past
an skb.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-10 17:32:11 +01:00
Jakub Kicinski 06554f4ffc tls: rx: factor out writing ContentType to cmsg
cmsg can be filled in during rx_list processing or normal
receive. Consolidate the code.

We don't need to keep the boolean to track if the cmsg was
created. 0 is an invalid content type.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-10 17:32:11 +01:00
Jakub Kicinski 37943f047b tls: rx: simplify async wait
Since we are protected from async completions by decrypt_compl_lock
we can drop the async_notify and reinit the completion before we
start waiting.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-10 17:32:11 +01:00
Jakub Kicinski 4175eac371 tls: rx: wrap decryption arguments in a structure
We pass zc as a pointer to bool a few functions down as an in/out
argument. This is error prone since C will happily evalue a pointer
as a boolean (IOW forgetting *zc and writing zc leads to loss of
developer time..). Wrap the arguments into a structure.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-10 17:32:11 +01:00
Jakub Kicinski 9bdf75ccff tls: rx: don't report text length from the bowels of decrypt
We plumb pointer to chunk all the way to the decryption method.
It's set to the length of the text when decrypt_skb_update()
returns.

I think the code is written this way because original TLS
implementation passed &chunk to zerocopy_from_iter() and this
was carried forward as the code gotten more complex, without
any refactoring.

The fix for peek() introduced a new variable - to_decrypt
which for all practical purposes is what chunk is going to
get set to. Spare ourselves the pointer passing, use to_decrypt.

Use this opportunity to clean things up a little further.

Note that chunk / to_decrypt was mostly needed for the async
path, since the sync path would access rxm->full_len (decryption
transforms full_len from record size to text size). Use the
right source of truth more explicitly.

We have three cases:
 - async - it's TLS 1.2 only, so chunk == to_decrypt, but we
           need the min() because to_decrypt is a whole record
	   and we don't want to underflow len. Note that we can't
	   handle partial record by falling back to sync as it
	   would introduce reordering against records in flight.
 - zc - again, TLS 1.2 only for now, so chunk == to_decrypt,
        we don't do zc if len < to_decrypt, no need to check again.
 - normal - it already handles chunk > len, we can factor out the
            assignment to rxm->full_len and share it with zc.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-10 17:32:11 +01:00
Jakub Kicinski d4bd88e676 tls: rx: drop unnecessary arguments from tls_setup_from_iter()
sk is unused, remove it to make it clear the function
doesn't poke at the socket.

size_used is always 0 on input and @length on success.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-10 17:32:11 +01:00
Jakub Kicinski 71471ca325 tls: hw: rx: use return value of tls_device_decrypted() to carry status
Instead of tls_device poking into internals of the message
return 1 from tls_device_decrypted() if the device handled
the decryption.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-08 11:49:09 +01:00
Jakub Kicinski 3764ae5ba6 tls: rx: refactor decrypt_skb_update()
Use early return and a jump label to remove two indentation levels.
No functional changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-08 11:49:08 +01:00
Jakub Kicinski 5dbda02d32 tls: rx: don't issue wake ups when data is decrypted
We inform the applications that data is available when
the record is received. Decryption happens inline inside
recvmsg or splice call. Generating another wakeup inside
the decryption handler seems pointless as someone must
be actively reading the socket if we are executing this
code.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-08 11:49:08 +01:00
Jakub Kicinski 5deee41b19 tls: rx: replace 'back' with 'offset'
The padding length TLS 1.3 logic is searching for content_type from
the end of text. IMHO the code is easier to parse if we calculate
offset and decrement it rather than try to maintain positive offset
from the end of the record called "back".

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-08 11:49:08 +01:00
Jakub Kicinski a8340cc02b tls: rx: use a define for tag length
TLS 1.3 has to strip padding, and it starts out 16 bytes
from the end of the record. Make it clear this is because
of the auth tag.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-08 11:49:08 +01:00
Jakub Kicinski 863533e316 tls: rx: init decrypted status in tls_read_size()
We set the record type in tls_read_size(), can as well init
the tlm->decrypted field there.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-08 11:49:08 +01:00
Jakub Kicinski 7dc59c33d6 tls: rx: don't store the decryption status in socket context
Similar justification to previous change, the information
about decryption status belongs in the skb.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-08 11:49:08 +01:00