Before this patch, IPv4-compatible addresses (::ffff:aaa.bbb.ccc.ddd)
may be used if a quic6://some.domain:port is specified and both IPv4 and
IPv6 addresses exist for that domain name.
* Trigger connection loop on config device addition (fixes#7600)
* Also check for device address equality
* Move EqualStrings from api_test to utils, and use in connections/service.go
* Make sure CommitConfiguration cannot block due on the deviceAddressesChanged channel
* Update lib/connections/service.go
Co-authored-by: Jakob Borg <jakob@kastelo.net>
This truncates times meant for API consumption to second precision,
where fractions won't typically matter or add any value. Exception to
this is timestamps on logs and events, and of course I'm not touching
things like file metadata.
I'm not 100% certain this is an exhaustive change, but it's the things I
found by grepping and following the breadcrumbs from lib/api...
I also considered general-but-ugly solutions, like having the API
serializer itself do reflection magic or even regexps on returned
objects, but decided against it because aurgh...
This adds two new configuration options:
// The number of connections at which we stop trying to connect to more
// devices, zero meaning no limit. Does not affect incoming connections.
ConnectionLimitEnough int
// The maximum number of connections which we will allow in total, zero
// meaning no limit. Affects incoming connections and prevents
// attempting outgoing connections.
ConnectionLimitMax int
These can be used to limit the number of concurrent connections in
various ways.
This adds a statistic to track the last connection duration per device.
It isn't used for much in this PR, but it's available for #7223 to use
in deciding how to order device connection attempts (deprioritizing
devices that just dropped our connection the last time).
This breaks out some methods from the connection loop to make it simpler
to manage and understand.
Some slight simplifications to remove the `seen` variable (we can filter
`nextDial` based on times are in the future or not, so we don't need to
track `seen`) and adding a minimum loop interval (5s) in case some
dialer goes haywire and requests a 0s redial interval or such.
Otherwise no significant behavioral changes.
This does two things:
- Exclude QUIC from go1.16 builds, automatically, for now, since it
doesn't work and just panics.
- Provide some fake listeners and dialers when QUIC is disabled.
These fake listeners and dialers indicate that they are disabled and
unsupported, which silences "Dialing $address: unknown address scheme:
quic" type of stuff which is not super helpful to the user.
Our authentication is based on device ID (certificate fingerprint) but
we also check the certificate name for ... historical extra security
reasons. (I don't think this adds anything but it is what it is.) Since
that check breaks in Go 1.15 this change does two things:
- Adds a manual check for the peer certificate CommonName, and if they
are equal we are happy and don't call the more advanced
VerifyHostname() function. This allows our old style certificates to
still pass the check.
- Adds the cert name "syncthing" as a DNS SAN when generating the
certificate. This is the correct way nowadays and makes VerifyHostname()
happy in Go 1.15 as well, even without the above patch.
The QUIC package is notorious for being incompatible with either too
old or too new Go releases. Currently it doesn't build with Go 1.15 RC
and I want to test the rest with Go 1.15. With this I can do `go run
build.go --tags noquic` to do that.
- In the few places where we wrap errors, use the new Go 1.13 "%w"
construction instead of %s or %v.
- Where we create errors with constant strings, consistently use
errors.New and not fmt.Errorf.
- Remove capitalization from errors in the few places where we had that.
This splits large writes into smaller ones when using a rate limit,
making them into a legitimate trickle rather than large bursts with a
long time in between.
* lib/api, lib/connections, gui: Show connection error for disconnected devices (fixes#3345)
This adds functionality in the connetions service to track the last
error per address. That is in turn exposed in the /rest/system/status
API method, as that is also where we already show the listener status
from the connection service.
The GUI uses this info where it lists addresses, showing errors (if any)
in red underneath each address.
I also slightly refactored the existing status method on the connection
service to have a better name and return typed information.
* ok
* review
* formatting
* review
* lib/tlsutil: Enable TLS 1.3 when available, on test builds (fixes#5065)
This enables TLS 1.3 negotiation on Go 1.12 by setting the GODEBUG
variable. For now, this just gets enabled on test versions (those with a
dash in the version number).
Users wishing to enable this on production builds can set GODEBUG
manually.
The string representation of connections now includes the TLS version
and cipher suite. This becomes part of the log output on connections.
That is, when talking to an old client:
Established secure connection .../TLS1.2-TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
and now potentially:
Established secure connection .../TLS1.3-TLS_AES_128_GCM_SHA256
(The cipher suite was there previously in the log output, but not the
TLS version.)
I also added this info as a new Crypto() method on the connection, and
propagate this out to the API and GUI, where it can be seen in the
connection address hover (although with bad word wrapping sometimes).
* wip
* wip
This avoids waiting until next ping and timeout until the connection is actually
closed both by notifying the peer of the disconnect and by immediately closing
the local end of the connection after that. As a nice side effect, info level
logging about dropped connections now have the actual reason in it, not a generic
timeout error which looks like a real problem with the connection.
Two small behavior changes: don't "charge" the data to the global rate
limit until it's been accepted by the device specific limiter, and fix
the send/recv direction in the log print on per device rate limits.