Currently, historically, we look for the `X-API-Key` header to
authenticate with an API key. There's nothing wrong with this, but in
some scenarios it's easier to produce an `Authorization` header with a
`Bearer $token` content, which is nowadays more common. This change adds
support for both, so that we will accept an API key either in our custom
header or as a bearer token.
Currently, because of devices with unset RTC clock, the 100% percentile
for Uptime on [1] is calculated since the Unix epoch which is useless as
far as usage statistics are concerned. Thus, if the Syncthing start time
is set to a past date, assume that the clock is wrong and do not even
try to report the uptime.
[1] https://data.syncthing.net
Signed-off-by: Tomasz Wilczyński <twilczynski@naver.com>
Co-authored-by: Jakob Borg <jakob@kastelo.net>
refactor: replace empty slice literal with `var`
An empty slice can be represented by `nil` or an empty slice literal. They are
functionally equivalent — their `len` and `cap` are both zero — but the `nil`
slice is the preferred style. For more information about empty slices,
see [Declaring Empty Slices](https://github.com/golang/go/wiki/CodeReviewComments#declaring-empty-slices).
Co-authored-by: deepsource-autofix[bot] <62050782+deepsource-autofix[bot]@users.noreply.github.com>
refactor: fix unused method receiver
Methods with unused receivers can be a symptom of unfinished refactoring or a bug. To keep
the same method signature, omit the receiver name or '_' as it is unused.
Co-authored-by: deepsource-autofix[bot] <62050782+deepsource-autofix[bot]@users.noreply.github.com>
refactor: unused parameter should be replaced by underscore
Unused parameters in functions or methods should be replaced with `_`
(underscore) or removed.
Co-authored-by: deepsource-autofix[bot] <62050782+deepsource-autofix[bot]@users.noreply.github.com>
This adds an environment variable STVERSIONEXTRA that, when set, gets
added to the version information in the API and GUI.
The purpose of all this is to be able to communicate something about the
bundling or packaging, through the log & GUI and the end user, to the
potential person supporting it -- i.e., us. :) A wrapper can set this
variable to indicate that Syncthing is being run via `SyncTrayzor`,
`Syncthing-macOS`, etc., and thus indicate to the end user that the GUI
they are looking at is perhaps not the only source of truth and
management for this instance.
With this change, error messages include the offending characters or
name parts. Examples:
nul.txt: name is invalid, contains Windows reserved name: "nul"
foo>bar.txt: name is invalid, contains Windows reserved character: ">"
foo \bar.txt: name is invalid, must not end in space or period on Windows
This prevents combining untrusted with introducer and auto-accept, and
also verifies that folders shared with untrusted devices have passwords
at config loading time.
Co-authored-by: Simon Frei <freisim93@gmail.com>
We usually want to ensure that our own device is present. However if the
given device ID is the empty ID, we shouldn't do that. This is a
legimate (though way too non-obvious) use-case when opening the config
without knowing/caring about the device ID.
* Platform data (ownership, xattrs, etc.) is now set correctly for newly-received folders, even if the received folder has the NoPermissions flag.
* Call setPlatformData on receivers that have ignorePerms set to true.
This fixes various test issues with Go 1.20.
- Most tests rewritten to use fakefs where possible
- Some tests that were already skipped, or dubious (invasive,
unmaintainable, unclear what they even tested) have been removed
- Some actual code rewritten to better support testing in fakefs
Co-authored-by: Eric P <eric@kastelo.net>
In the sequence of loading ignores, the error File Does Not Exist is not being considered a fatal error, since the .stignore file is allowed to not exist. However, included ignore files also tossed that same error in case those do not exist while in those cases it's considered an error and it should lead to the folder stopping. Changing the error when opening an included ignore file to something other than the regular does fix this issue, as in it now works again as described in the Documentation.
This makes the various protocol priorities configurable among the other
options. With this, it's possible to prefer QUIC over TCP for WAN
connections, for example. Both sides need to be similarly configured for
this to work properly.
The default priority order remains the same as previously (TCP, QUIC,
Relay, with LAN better than WAN).
To make this happen I made each dialer & listener more priority aware,
and moved the check for whether a connection is LAN or not into the
dialer / listener -- this is the new "lanChecker" type that's passed
around.
In the original fix in #8563 I simply forgot this. Which meant #8556
wasn't actually fixed, as the trialer size would have been 0 (default),
and thus we would have still sent the inflated size to encrypted peers.
lib/model: Fix file size inconsisency due to enc. trailer
Fixes a regression due to PR #8563, while arguable the bug was actually
introduced in a much older PR #7155, but didn't have any bad effects so
far:
We account for the encryption trailer in the db updater routine,
calculating the file-info size there. However there's no guarantee that
the file-info at this point is still the exact same as when it was
written. It was before, but isn't anymore since introducing the new
EncryptedTrailerSize field.
Fix: Adjust the size in the info at the same place where the trailer is
written, i.e. we definitely have the actual size on disk.
The layout of the request differs based on whether it comes from an
untrusted device or a trusted device with encrypted enabled. Handle
both.
Closes#8819.
Allow the watcher delay to take fractional values, effectively allowing
for much shorter delays. The minimum value is limited at 0.01, which
effectively translates to 10ms. This is required in order to guarantee
that there is still enough time to aggregate multiple single change
events.
Signed-off-by: Tomasz Wilczyński <twilczynski@naver.com>
This adds a cache to the expensive key generation operations. It's fixes
size LRU/MRU stuff to keep memory usage bounded under absurd conditions.
Also closes#8600.
This adds the BlocksHash field from the FileInfo to our API output. It
can be useful for debugging, or for external tools. I'm intentionally
leaving it as an opaque base64 string because no meaning should be
derived from it: it's just a string.
This makes sure the service manager doesn't interpret timeout errors, or any other error, as a signal to stop the service instead of restarting it.
I added it directly to our service utility function, as it may help catch other instances of the same problem... We would typically want timeouts etc to be a retryable error, unless it is the top level context that has timed out and we check for that specifically.
This adds a word to the version string when running containerized. The
purpose is mostly to facilitate troubleshooting via screenshot by
"leaking" this rather important aspect of the setup. Additionally, the
version row gets "no-overflow-ellipsis" treatment so that the whole
thing is actually visible in the GUI and the (now useless) tooltip is
removed. In production releases this won't make a difference as the
whole thing will typically fit, but in odd setups it provides more info
up front.
* lib/connections: Cache isLAN decision for later external access.
The check whether a remote device's address is on a local network
currently happens when handling the Hello message, to configure the
limiters. Save the result to the ConnectionInfo and pass it out as
part of the model's ConnectionInfo struct in ConnectionStats().
* gui: Use provided connection attribute to distinguish LAN / WAN.
Replace the dumb IP address check which didn't catch common cases and
actually could contradict what the backend decided. That could have
been confusing if the GUI says WAN, but the limiter is not actually
applied because the backend thinks it's a LAN.
Add strings for QUIC and relay connections to also differentiate
between LAN and WAN.
* gui: Redefine reception level icons for all connection types.
Move the mapping to the JS code, as it is much easier to handle
multiple switch cases by fall-through there.
QUIC is regarded no less than TCP anymore. LAN and WAN make the
difference between levels 4 / 3 and 2 / 1:
{TCP,QUIC} LAN --> {TCP,QUIC} WAN --> Relay LAN --> Relay WAN -->
Disconnected.
Previous debug input didn't really give enough info to show what was
happening, while it also printed full block lists which are enormously
verbose. Now it consistently prints 1. what it sees on disk, 2. what it
got from CurrentFile (without blocks), 3. the action taken on that file.
There are some situations where an upgrade wouldn't be supported, even though the noUpgrade bool isn't set. So when handling the errors that are caused by this, when attempting an upgrade, it shouldn't lead to some sort of offline-message/restart/warning/etc...
I added some checks on specific errors related to this and return a 501 (Not Implemented) response instead, in case of an "UpgradeUnsupported"-error. Additionally, on the GUI-side, the 501-response is now not to be considered an error to act upon.
* implement authentication via token for relaysrv
Make replaysrv check for a token before allowing clients to
join. The token can be set via the replay-uri.
* fix formatting
* key composite literal
* do not error out if auth material is provided but not needed
* remove unused method receiver
* clean up unused parameter in functions
* cleaner token handling, disable joining the pool if token is set.
* Keep backwards compatibility with older clients.
In prior versions of the protocol JoinRelayRequest did not have a
token field. Trying to unmarshal such a request will result in
an error. Return an empty JoinRelayRequest, that is a request
without token, instead.
Co-authored-by: entity0xfe <entity0xfe@my.domain>
The restore function of Trash Can ran a rename at the end regardless of whether there was anything to rename. In this case, when the file-to-be-restored did not exist in the destination folder, this resulted in an error. I added a simple check, keeping track of whether the file existed prior to restoring it in the destination folder and depending on this value it will now return nil after the restoration to prevent the renaming function to kick off. Added a test for this specific edge-case as well.
This adds support for syncing extended attributes on supported
filesystem on Linux, macOS, FreeBSD and NetBSD. Windows is currently
excluded because the APIs seem onerous and annoying and frankly the uses
cases seem few and far between. On Unixes this also covers ACLs as those
are stored as extended attributes.
Similar to ownership syncing this will optional & opt-in, which two
settings controlling the main behavior: one to "sync" xattrs (read &
write) and another one to "scan" xattrs (only read them so other devices
can "sync" them, but not apply any locally).
Co-authored-by: Tomasz Wilczyński <twilczynski@naver.com>
The cleaning logic in util.go was used by Simple and Trashcan but only
really suited Trashcan since it works based on mtimes which Simple does
not use. The cleaning logic in util.go was moved to trashcan.go.
Staggered and Simple seemed to be able to benefit from the same base so
util.go now has the base for those two with an added parameter which
takes a function so it can still handle versioner-specific logic to
decide which files to clean up. Simple now also correctly cleans files
based on their time-stamp in the title together with a specific maximum
amount to keep. The Archive function in Simple.go was changed to get rid
of duplicated code.
Additionally the trashcan testcase which was used by Trashcan as well as
Simple was moved from versioner_test.go to trashcan_test.go to keep it
clean, there was no need to keep it in a separate test file
This replaces old style errors.Wrap with modern fmt.Errorf and removes
the (direct) dependency on github.com/pkg/errors. A couple of cases are
adjusted by hand as previously errors.Wrap(nil, ...) would return nil,
which is not what fmt.Errorf does.
Locally paused folders will fail on checkFolderRunningLocked() and
therefore abort the loop. Avoid this by skipping paused folders
directly.
Co-authored-by: Jakob Borg <jakob@kastelo.net>
* lib/locations: Fix enum values camelCase.
* lib/locations: Remove unused FailuresFile.
* cmd/syncthing: Turn around role of locations storage.
Previously the locations package was used to provide default paths,
possibly with an overridden home directory. Extra paths supplied on
the command line were handled and passed around in the options object.
To make the changed paths available to any other interested package,
override the location setting from the option if supplied, instead of
vice versa when not supplied. Adapt code using this to read from the
locations package instead of passing through the options object.
* lib/locations: Refactor showPaths to locations package.
Generate a reusable string in locations.PrettyPrintPaths().
Enumerating all possible locations in different packages is error
prone, so add a new public function to generate the listing as a
string in the locations package. Adapt cmd/syncthing --paths to use
that instead of its own console output.
* lib/locations: Include CSRF token in pretty printed paths.
* lib/api: New endpoint /rest/system/paths.
The paths should be available for troubleshooting from a running
instance. Using the --paths CLI option is not easy in some
environments, so expose the locations mapping to a JSON endpoint.
Add utility function ListExpandedPaths() that also filters out any
entries which still contain variable placeholders.
* gui: List runtime paths in separate log viewer tab.
* Wrap paths.
* lib/syncthing: Utilize locations.Get() instead of passing an arg.
* Include base directories, move label to table caption.
* gui: Switch to hard-coded paths instead of iterating over all.
* gui: Break aboutModalView into tabs.
Use tabs to separate authors from included third-party software.
* gui: Move paths from log viewer to about modal.
* lib/locations: Adjust pretty print output order to match GUI.
* gui, authors: Remove additional bot names and fix indent.
The indentation changed because of the tabbed about dialog, fix the
authors script to respect that.
Skip Syncthing*Automation in authors list as well.
* Update AUTHORS list to remove bot names.
* Revert AUTHORS email order change.
* Do not emphasize DB and log file locations.
* Review line wrapping.
* review part 1: strings.Builder, naming
* Rename and extend locations.Set() with error handling.
Remodel the Override() function along the existing SetBaseDir() and
rename it to simply Set(). Make sure to use absolute paths when given
log file or GUI assets override options. Add proper error reporting
if that goes wrong.
* Remove obsolete comment about empty logfile option.
* Don't filter out unexpanded baseDir placeholders, only ${timestamp}.
* Restore behavior regarding special "-" logfile argument.
If the option is given, but with empty value, assume the no log
file (same as "-"). Don't try to convert the special value to an
absolute path though and document this fact in a comment for the Set()
function.
* Use template to check for location key validity.
* Don't filter out timestamp placeholders.
* lib/api: Remove paths from /rest/system/status.
* lib/ur: Properly initialize map in failure data (fixes#8479)
Co-authored-by: Jakob Borg <jakob@kastelo.net>
Also adds idle time and keepalive parameters because how this is
configured has changed in the new package version. The values are those
that seems like might already be default, if keep-alives were enabled,
which is not obvious from the doc comments.
Also, Go 1.19 gofmt reformatting of comments.
all: Add package runtimeos for runtime.GOOS comparisons
I grew tired of hand written string comparisons. This adds generated
constants for the GOOS values, and predefined Is$OS constants that can
be iffed on. In a couple of places I rewrote trivial switch:es to if:s,
and added Illumos where we checked for Solaris (because they are
effectively the same, and if we're going to target one of them that
would be Illumos...).
This adds support for syncing ownership on Unixes and on Windows. The
scanner always picks up ownership information, but it is not applied
unless the new folder option "Sync Ownership" is set.
Ownership data is stored in a new FileInfo field called "platform data". This
is intended to hold further platform-specific data in the future
(specifically, extended attributes), which is why the whole design is a
bit overkill for just ownership.
* lib/model: Override scan config for auto-accepted encrypted folders.
Encrypted folders should not have the fs watcher enabled and rarely
benefit from a scheduled rescan. The GUI adjusts the suggested
settings (watcher disabled, one day rescan interval) when accepting a
receive-encrypted folder. Mirror that behavior to the auto-accept
case where the GUI is not involved.
Versioning also does not work well for encrypted folders, same
treatment.
An off-by-one error could cause tokens to be forgotten. Suppose
tokens := []string{"foo", "bar", "baz", "quux"}
i := 2
token := tokens[i] // token == "baz"
Then, after
copy(tokens[1:], tokens[:i+1])
tokens[0] = token
we have
tokens == []string{"baz", "foo", "bar", "baz"}
The short test actually relied on this bug.
This commit replaces `os.MkdirTemp` with `t.TempDir` in tests. The
directory created by `t.TempDir` is automatically removed when the test
and all its subtests complete.
Prior to this commit, temporary directory created using `os.MkdirTemp`
needs to be removed manually by calling `os.RemoveAll`, which is omitted
in some tests. The error handling boilerplate e.g.
defer func() {
if err := os.RemoveAll(dir); err != nil {
t.Fatal(err)
}
}
is also tedious, but `t.TempDir` handles this for us nicely.
Reference: https://pkg.go.dev/testing#T.TempDir
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
Showing all folders from disconnected or paused remote devices as
unaccepted would be a lot of false positives. As we cannot know
whether the remote has accepted while it doesn't have an active
connection, let's better report false negatives, as in assuming the
folders are accepted.
* lib/api: Note ItemStarted and ItemFinished for default filtering.
The reasoning why LocalChangeDetected and RemoteChangeDetected events
are not included in the event stream by default (without explicit
filter mask requested) also holds for the ItemStarted and ItemFinished
events. They should be excluded as well when we start to break the
API compatibility for some reason.
* gui: Enumerate unused event types in the eventService.
Define constants for the unused event types as well, for completeness'
sake. They are intentionally not handled in the GUI currently.
* cmd/syncthing: Harmonize uppercase CLI argument placeholders.
Use ALL-UPPERCASE and connecting dashes to distinguish argument
placeholders from literal argument options (e.g. "cpu" or "heap" for
profiling). The dash makes it clear which words form a single
argument and where a new argument starts.
This style is already used for the "syncthing cli debug file" command.
* lib/model: Simplify event data structure.
Using map[string]interface{} is not necessary when all values are
known to be strings.
Having a separate mutex for the three or four instructions needed to
fetch and increment nextID means the overhead exceeds the cost of this
operation. nextID is now handled inside the critical section for
awaiting instead, while the more expensive channel creation has been
moved outside it.
This is mostly a simplification, though it may have minor performance
benefits in some situations. The single-threaded sender benchmark shows
no significant difference:
name old speed new speed delta
RequestsRawTCP-8 55.3MB/s ± 7% 56.6MB/s ± 6% ~ (p=0.190 n=10+10)
RequestsTLSoTCP-8 20.5MB/s ±20% 20.8MB/s ± 8% ~ (p=0.604 n=10+9)
Staggered File Versioning used to have its own cleanInterval that
controlled how often file versions were cleaned. Nowadays, there is a
seperate setting called cleanupIntervalS responsible for the cleanup,
which applies to all File Versioning (except External). Thus, remove the
unneeded code and don't set the param up on new folders anymore.
Signed-off-by: Tomasz Wilczyński <twilczynski@naver.com>
* lib/protocol: Require at least 3.125% savings from compression
The new lz4 library doesn't need its output buffer to be the maximum
size, unlike the old one (which would allocate if it weren't). It can
take a buffer that is of a smaller size and will report if compressed
data can fit inside the buffer (with a small chance of reporting a false
negative). Use that property to our advantage by requiring compressed
data to be at most n-n/32 = .96875*n bytes long for n input bytes.
* lib/protocol: Remove unused receivers
To make DeepSource happy.
* lib/protocol: Micro-optimize lz4Compress
Only write the length if compression was successful. This is a memory
write, so the compiler can't reorder it.
Only check the return value of lz4.CompressBlock. Length-zero inputs
are always expanded by LZ4 compression (the library documents this),
so the check on len(src) isn't needed.
* lib/model: Remove bogus fields from connections API endpoint.
Switch the returned data type for the /rest/system/connections element
"total" to use only the Statistics struct. The other fields of the
ConnectionInfo struct are not populated and misleading.
* Lowercase JSON field names.
* lib/model: Get rid of ConnectionInfo.MarshalJSON().
It was missing the StartedAt field from the embedded Statistics
struct. Just lowercasing the JSON attribute names can be done just as
easily with annotations.
* lib/model: Remove bogus startedAt field from totals.
Instead of using the Statistics type with one field empty, just switch
to a free-form map with the three needed fields.
* cmd/syncthing: Remove unnecessary function arguments.
The openGUI() function does not need a device ID to work, and there is
only one caller anyway which uses EmptyDeviceID.
The loadOrDefaultConfig() function is always called with the same
dummy values.
* cmd/syncthing: Avoid misleading info messages from monitor process.
In order to check whether panic reporting is enabled, the monitor
process utilizes the loadOrDefaultConfig() function. In case there is
no config file yet, info messages may be logged during creation if the
config Wrapper, which is discarded immediately after.
Stop using the DefaultConfig() utility function from lib/syncthing and
directly generate a minimal config instead to avoid these.
Add comments to loadOrDefaultConfig() explaining its limited purpose.
* cmd/syncthing/generate: Always write updated config file.
Previously, an existing config file was left untouched unless either
of the --gui-user or --gui-password options was given. Remove that
condition and simplify the checking code.
* lib/config: Factor out ProbeFreePorts().
* cmd/syncthing: Add option --skip-port-probing.
Applies to both the "generate" and "serve" subcommands, as well as the
deprecated --generate option, just as the --no-default-folder flag.
When pathSep is a constant, the compiler precomputes pathSep+pathSep and
".."+pathSep instead of emitting function calls to compute "//" and
"../". Benchmark results in lib/osutil:
name old time/op new time/op delta
TraversesSymlink-8 8.86µs ± 3% 8.53µs ± 4% -3.79% (p=0.000 n=18+20)
name old alloc/op new alloc/op delta
TraversesSymlink-8 1.06kB ± 0% 1.06kB ± 0% ~ (all equal)
name old allocs/op new allocs/op delta
TraversesSymlink-8 15.0 ± 0% 15.0 ± 0% ~ (all equal)
The locking protocol in nat.Mapping was racy:
* Mapping.addressMap RLock'd, but then returned a map shared between
caller and Mapping, so the lock didn't do anything.
* Operations inside Service.{verifyExistingMappings,acquireNewMappings}
would lock the map for every update, but that means callers to
Mapping.ExternalAddresses can be looping over the map while the
Service methods are concurrently modifying it. When the Go runtime
detects that happening, it panics.
* Mapping.expires was read and updated without locking.
The Service methods now lock the map once and release the lock only when
done.
Also, subscribers no longer get the added and removed addresses, because
none of them were using the information. This was changed for a previous
attempt to retain the fine-grained locking and not reverted because it
simplifies the code.
Accept a subcommand as an alternative to the --generate option. It
accepts a custom config directory through either the --home or
--config options, using the default location if neither is given.
Add the options --gui-user and --gui-password to "generate", but not
the "serve --generate" option form. If either is given, an existing
config will not abort the command, but rather load, modify and save it
with the new credentials. The password can be read from standard
input by passing only a single dash as argument.
Config modification is skipped if the value matches what's already in
the config.
* cmd/syncthing: Utilize lib/locations package in generate().
Instead of manually joining paths with "magic" file names, get them
from the centralized locations helper lib.
* cmd/syncthing: Simplify logging for --generate option.
Visible change: No more timestamp prefixes.
What hash is used to store the password should ideally be an
implementation detail, so that every user of the GUIConfiguration
object automatically agrees on how to handle it. That is currently
distribututed over the confighandler.go and api_auth.go files, plus
tests.
Add the SetHasedPassword() / CompareHashedPassword() API to keep the
hashing method encapsulated. Add a separate test for it and adjust
other users and tests. Remove all deprecated imports of the bcrypt
package.
LoadOrGenerateCertificate() takes two file path arguments, but then
uses the locations package to determine the actual path. Fix that
with a minimally invasive change, by using the arguments instead.
Factor out GenerateCertificate().
The only caller of this function is cmd/syncthing, which passes the
same values, so this is technically a no-op.
* lib/tlsutil: Make storing generated certificate optional. Avoid
temporary cert and key files in tests, keep cert in memory.
Consistently use double dashes and fix typos -conf, -data-dir and
-verify.
Applies also to tests running the syncthing binary for consistency.
* Fix mismatched option name --conf in cli subcommand.
According to the source code comments, the cli option flags should
mirror those from the serve subcommand where applicable. That one is
actually called --config though.
* cli: Fix help text option placeholders.
The urfave/cli package uses the Value field of StringFlag to provide a
default value, not to name the placeholder. That is instead done with
backticks around some part of the Usage field.
* cli: Add missing --data flag in subcommand help text.
The urfave/cli based option parsing uses a fake flags collection to
generate help texts matching the used global options. But the --data
option was omitted from it, although it is definitely required when
using --config as well. Note that it cannot just be ignored, as some
debug stuff actually uses the DB:
syncthing cli --data=/bar --config=/foo debug index dump
By truncating time.Time to an int64 nanosecond count, we lose the
ability to precisely order timestamps before 1678 or after 2262, but we
gain (linux/amd64, Go 1.17.1):
name old time/op new time/op delta
JobQueuePushPopDone10k-8 2.85ms ± 5% 2.29ms ± 2% -19.80% (p=0.000 n=20+18)
JobQueueBump-8 34.0µs ± 1% 29.8µs ± 1% -12.35% (p=0.000 n=19+19)
name old alloc/op new alloc/op delta
JobQueuePushPopDone10k-8 2.56MB ± 0% 1.76MB ± 0% -31.31% (p=0.000 n=18+13)
name old allocs/op new allocs/op delta
JobQueuePushPopDone10k-8 23.0 ± 0% 23.0 ± 0% ~ (all equal)
Results for BenchmarkJobQueueBump are with the fixed version, which no
longer depends on b.N for the amount of work performed. rand.Rand.Intn
is cheap at ~10ns per iteration.
Like Windows and Mac, Android is also an interactive operating system.
On top of that, it usually runs on much slower hardware than the other
two. Because of that, it makes sense to limit the number of hashes used
by default there too.
Signed-off-by: Tomasz Wilczyński <twilczynski@naver.com>
Registry.Get used a full sort to get the minimum of a list, and the sort
was broken because util.AddressUnspecifiedLess assumed it could find out
whether an address is IPv4 or IPv6 from its Network method. However,
net.(TCP|UDP)Addr.Network always returns "tcp"/"udp".
The current detection is flawed, because it looks for a few specific
file systems like "msdos" or "fat" to set the mtime window, while in
reality Android seems to report names like "fuseblk", which can stand
for fat, ext4, or even f2fs.
At the moment, we set the mtime window only for a few known names used
for the fat filesystem. With this change, we take a safer approach of
always setting the time window unless we explicitly detect file systems
like ext2/ext3/ex4, which are known not to experience issues with moving
timestamps on Android.
Signed-off-by: Tomasz Wilczyński <twilczynski@naver.com>