The tunnel's real bottleneck queue - the UDP receive buffer feeding the
decrypt loop - is invisible to every kernel AQM, so under overload it
regulates ECN-capable flows with tail-drop loss like it's 1993. Sample
SK_MEMINFO once per recvmmsg batch (tunnels.ecn_mark_threshold, fraction
of rcvbuf, 0=off) and treat depth beyond the threshold as an outer CE:
the existing RFC 6040 fold then CE-marks ECT inner packets and senders
back off without loss.
The TX arena (128 x 9033B per routine) and GRO receive scratch
(listen.batch x 64KiB per socket) stay at their worst-case bounds by
design: the arena never grows past real demand and the GRO slots cannot
be smaller without truncating coalesced superpackets. Document the
listen.batch knob's memory implication so constrained hosts know what
to tune.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Thread pinning trades scheduler freedom for TX-ring ordering; that's the
right trade on dedicated forwarders but not as a surprise default on
hosts sharing cores with other workloads. Make it opt-in and document
the default in the example config.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* add IPv6 reject packet generation (ICMPv6 Destination Unreachable and TCP RST)
* use ICMPv6 code 1 (administratively prohibited) and cap body at 1000 bytes
* cleanup, use ICMP error code 13 for ipv4
* better docs
* cleanup
* add sshd.sandbox_dir config option
Sanitize SSH profile paths (ssh.go:514,683,719) — restrict os.Create(a[0]) to a safe directory.
Add a config option in the config file to specify the sandbox directory. For backwards compatibility, if the config is not specified, keep the current behavior.
* update default and example
* use os.TempDir() for sshd.sandbox_dir default
* split sandbox path validation into separate conditionals
Separate the combined && check in sshSanitizeFilePath into two distinct
conditionals with specific error messages: one for paths resolving to the
sandbox directory itself, and one for paths outside the sandbox.
Co-Authored-By: Claude <svc-devxp-claude@slack-corp.com>
* fix: trim leading zeros from p256 signature swap result
bigmod.Nat.Bytes() returns fixed-size 32-byte slices, but ASN.1 INTEGER
parsing strips leading zeros. This caused a flaky test failure (~1/256
chance) when the S value's high byte was zero.
Co-Authored-By: Claude <svc-devxp-claude@slack-corp.com>
---------
Co-authored-by: Claude <svc-devxp-claude@slack-corp.com>
- Accept certs signed by trusted CAs
- Username must match the cert principal if set
- Any username can be used if cert principal is empty
- Don't allow removed pubkeys/CAs to be used after reload
* add calculated_remotes
This setting allows us to "guess" what the remote might be for a host
while we wait for the lighthouse response. For networks that hard
designed with in mind, it can help speed up handshake performance, as well as
improve resiliency in the case that all lighthouses are down.
Example:
lighthouse:
# ...
calculated_remotes:
# For any Nebula IPs in 10.0.10.0/24, this will apply the mask and add
# the calculated IP as an initial remote (while we wait for the response
# from the lighthouse). Both CIDRs must have the same mask size.
# For example, Nebula IP 10.0.10.123 will have a calculated remote of
# 192.168.1.123
10.0.10.0/24:
- mask: 192.168.1.0/24
port: 4242
* figure out what is up with this test
* add test
* better logic for sending handshakes
Keep track of the last light of hosts we sent handshakes to. Only log
handshake sent messages if the list has changed.
Remove the test Test_NewHandshakeManagerTrigger because it is faulty and
makes no sense. It relys on the fact that no handshake packets actually
get sent, but with these changes we would send packets now (which it
should!)
* use atomic.Pointer
* cleanup to make it clearer
* fix typo in example
JackDoan