Commit Graph

186 Commits (b1248442c3e40371c34fdf5bd90138b3ece615a7)

Author SHA1 Message Date
Joe Tsai 531ccca648
util/deephash: delete slow path (#5423)
Every implementation of typeHasherFunc always returns true,
which implies that the slow path is no longer executed.
Delete it.

h.hashValueWithType(v, ti, ...) is deleted as it is equivalent to:
	ti.hasher()(h, v)

h.hashValue(v, ...) is deleted as it is equivalent to:
	ti := getTypeInfo(v.Type())
	ti.hasher()(h, v)

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai 3fc8683585
util/deephash: expand fast-path capabilities (#5404)
Add support for maps and interfaces to the fast path.
Add cycle-detection to the pointer handling logic.
This logic is mostly copied from the slow path.

A future commit will delete the slow path once
the fast path never falls back to the slow path.

Performance:

	name                 old time/op    new time/op    delta
	Hash-24                18.5µs ± 1%    14.9µs ± 2%  -19.52%  (p=0.000 n=10+10)
	HashPacketFilter-24    2.54µs ± 1%    2.60µs ± 1%   +2.19%  (p=0.000 n=10+10)
	HashMapAcyclic-24      31.6µs ± 1%    30.5µs ± 1%   -3.42%  (p=0.000 n=9+8)
	TailcfgNode-24         1.44µs ± 2%    1.43µs ± 1%     ~     (p=0.171 n=10+10)
	HashArray-24            324ns ± 1%     324ns ± 2%     ~     (p=0.425 n=9+9)

The additional cycle detection logic doesn't incur much slow down
since it only activates if a type is recursive, which does not apply
for any of the types that we care about.

There is a notable performance boost since we switch from the fath path
to the slow path less often. Most notably, a struct with a field that
could not be handled by the fast path would previously cause
the entire struct to go through the slow path.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Tom DNetto 18edd79421 control/controlclient,tailcfg: [capver 40] create KeySignature field in tailcfg.Node
We calve out a space to put the node-key signature (used on tailnets where network lock is enabled).

Signed-off-by: Tom DNetto <tom@tailscale.com>
2 years ago
Joe Tsai d32700c7b2
util/deephash: specialize for netip.Addr and drop AppendTo support (#5402)
There are 5 types that we care about that implement AppendTo:

	key.DiscoPublic
	key.NodePublic
	netip.Prefix
	netipx.IPRange
	netip.Addr

The key types are thin wrappers around [32]byte and are memory hashable.
The netip.Prefix and netipx.IPRange types are thin wrappers over netip.Addr
and are hashable by default if netip.Addr is hashable.
The netip.Addr type is the only one with a complex structure where
the default behavior of deephash does not hash it correctly due to the presence
of the intern.Value type.

Drop support for AppendTo and instead add specialized hashing for netip.Addr
that would be semantically equivalent to == on the netip.Addr values.

The AppendTo support was already broken prior to this change.
It was fully removed (intentionally or not) in #4870.
It was partially restored in #4858 for the fast path,
but still broken in the slow path.
Just drop support for it altogether.

This does mean we lack any ability for types to self-hash themselves.
In the future we can add support for types that implement:

	interface { DeepHash() Sum }

Test and fuzz cases were added for the relevant types that
used to rely on the AppendTo method.
FuzzAddr has been executed on 1 billion samples without issues.

Signed-off-by: Joe Tsai joetsai@digital-static.net
2 years ago
Joe Tsai 03f7e4e577
util/hashx: move from sha256x (#5388) 2 years ago
Joe Tsai f061d20c9d
util/sha256x: rename Hash as Block512 (#5351)
Rename Hash as Block512 to indicate that this is a general-purpose
hash.Hash for any algorithm that operates on 512-bit block sizes.

While we rename the package as hashx in this commit,
a subsequent commit will move the sha256x package to hashx.
This is done separately to avoid confusing git.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai 44d62b65d0
util/deephash: move typeIsRecursive and canMemHash to types.go (#5386)
Also, rename canMemHash to typeIsMemHashable to be consistent.
There are zero changes to the semantics.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai d53eb6fa11
util/deephash: simplify typeIsRecursive (#5385)
Any type that is memory hashable must not be recursive since
there are definitely no pointers involved to make a cycle.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai 23ec3c104a
util/deephash: remove unused stack slice in typeIsRecursive (#5363)
No operation ever reads from this variable.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai c200229f9e
util/deephash: simplify canMemHash (#5384)
Put the t.Size() == 0 check first since this is applicable in all cases.
Drop the last struct field conditional since this is covered by the
sumFieldSize check at the end.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai 32a1a3d1c0
util/deephash: avoid variadic argument for Update (#5372)
Hashing []any is slow since hashing of interfaces is slow.
Hashing of interfaces is slow since we pessimistically assume
that cycles can occur through them and start cycle tracking.

Drop the variadic signature of Update and fix callers to pass in
an anonymous struct so that we are hashing concrete types
near the root of the value tree.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Maisem Ali 545639ee44 util/winutil: consolidate interface specific registry keys
Code movement to allow reuse in a follow up PR.

Updates #1659

Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Joe Tsai 548fa63e49
util/deephash: use binary encoding of time.Time (#5352)
Formatting a time.Time as RFC3339 is slow.
See https://go.dev/issue/54093

Now that we have efficient hashing of fixed-width integers,
just hash the time.Time as a binary value.

Performance:

	Hash-24                19.0µs ± 1%    18.6µs ± 1%   -2.03%  (p=0.000 n=10+9)
	TailcfgNode-24         1.79µs ± 1%    1.40µs ± 1%  -21.74%  (p=0.000 n=10+9)

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai 1f7479466e
util/deephash: use sha256x (#5339)
Switch deephash to use sha256x.Hash.

We add sha256x.HashString to efficiently hash a string.
It uses unsafe under the hood to convert a string to a []byte.
We also modify sha256x.Hash to export the underlying hash.Hash
for testing purposes so that we can intercept all hash.Hash calls.

Performance:

	name                 old time/op    new time/op    delta
	Hash-24                19.8µs ± 1%    19.2µs ± 1%  -3.01%  (p=0.000 n=10+10)
	HashPacketFilter-24    2.61µs ± 0%    2.53µs ± 1%  -3.01%  (p=0.000 n=8+10)
	HashMapAcyclic-24      31.3µs ± 1%    29.8µs ± 0%  -4.80%  (p=0.000 n=10+9)
	TailcfgNode-24         1.83µs ± 1%    1.82µs ± 2%    ~     (p=0.305 n=10+10)
	HashArray-24            344ns ± 2%     323ns ± 1%  -6.02%  (p=0.000 n=9+10)

The performance gains is not as dramatic as sha256x over sha256 due to:
1. most of the hashing already occurring through the direct memory hashing logic, and
2. what does not go through direct memory hashing is slowed down by reflect.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai 77a92f326d
util/deephash: avoid using sync.Pool for reflect.MapIter (#5333)
In Go 1.19, the reflect.Value.MapRange method uses "function outlining"
so that the allocation of reflect.MapIter is inlinable by the caller.
If the iterator doesn't escape the caller, it can be stack allocated.
See https://go.dev/cl/400675

Performance:

	name               old time/op    new time/op    delta
	HashMapAcyclic-24    31.9µs ± 2%    32.1µs ± 1%   ~     (p=0.075 n=10+10)

	name               old alloc/op   new alloc/op   delta
	HashMapAcyclic-24     0.00B          0.00B        ~     (all equal)

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai 1c3c6b5382
util/sha256x: make Hash.Sum non-escaping (#5338)
Since Hash is a concrete type, we can make it such that
Sum never escapes the input.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai 76b0e578c5
util/sha256x: new package (#5337)
The hash.Hash provided by sha256.New is much more efficient
if we always provide it with data a multiple of the block size.
This avoids double-copying of data into the internal block
of sha256.digest.x. Effectively, we are managing a block ourselves
to ensure we only ever call hash.Hash.Write with full blocks.

Performance:

	name    old time/op    new time/op    delta
	Hash    33.5µs ± 1%    20.6µs ± 1%  -38.40%  (p=0.000 n=10+9)

The logic has gone through CPU-hours of fuzzing.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Joe Tsai 539c5e44c5
util/deephash: always keep values addressable (#5328)
The logic of deephash is both simpler and easier to reason about
if values are always addressable.

In Go, the composite kinds are slices, arrays, maps, structs,
interfaces, pointers, channels, and functions,
where we define "composite" as a Go value that encapsulates
some other Go value (e.g., a map is a collection of key-value entries).

In the cases of pointers and slices, the sub-values are always addressable.

In the cases of arrays and structs, the sub-values are always addressable
if and only if the parent value is addressable.

In the case of maps and interfaces, the sub-values are never addressable.
To make them addressable, we need to copy them onto the heap.

For the purposes of deephash, we do not care about channels and functions.

For all non-composite kinds (e.g., strings and ints), they are only addressable
if obtained from one of the composite kinds that produce addressable values
(i.e., pointers, slices, addressable arrays, and addressable structs).
A non-addressible, non-composite kind can be made addressable by
allocating it on the heap, obtaining a pointer to it, and dereferencing it.

Thus, if we can ensure that values are addressable at the entry points,
and shallow copy sub-values whenever we encounter an interface or map,
then we can ensure that all values are always addressable and
assume such property throughout all the logic.

Performance:

	name                 old time/op    new time/op    delta
	Hash-24                21.5µs ± 1%    19.7µs ± 1%  -8.29%  (p=0.000 n=9+9)
	HashPacketFilter-24    2.61µs ± 1%    2.62µs ± 0%  +0.29%  (p=0.037 n=10+9)
	HashMapAcyclic-24      30.8µs ± 1%    30.9µs ± 1%    ~     (p=0.400 n=9+10)
	TailcfgNode-24         1.84µs ± 1%    1.84µs ± 2%    ~     (p=0.928 n=10+10)
	HashArray-24            324ns ± 2%     332ns ± 2%  +2.45%  (p=0.000 n=10+10)

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Maisem Ali 40ec8617ac util/must: rename Do->Get, add Do
Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Brad Fitzpatrick 01e8ef7293 util/strs: add new package for string utility funcs
Updates #5309

Change-Id: I677cc6e01050b6e10d8d6907d961b11c7a787a05
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Joe Tsai 622d80c007
util/must: new package (#5307)
The Do function assists in calling functions that must succeed.
It only interacts well with functions that return (T, err).
Signatures with more return arguments are not supported.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
2 years ago
Maisem Ali a9f6cd41fd all: use syncs.AtomicValue
Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Mihai Parparita 4aa88bc2c0 cmd/tsconnect,util/precompress: move precompression to its own package
We have very similar code in corp, moving it to util/precompress allows
it to be reused.

Updates #5133

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Brad Fitzpatrick 8725b14056 all: migrate more code code to net/netip directly
Instead of going through the tailscale.com/net/netaddr transitional
wrappers.

Updates #5162

Change-Id: I3dafd1c2effa1a6caa9b7151ecf6edd1a3fda3dd
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 116f55ff66 all: gofmt for Go 1.19
Updates #5210

Change-Id: Ib02cd5e43d0a8db60c1f09755a8ac7b140b670be
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 04cf46a762 util/deephash: fix unexported time.Time hashing
Updates tailscale/corp#6311

Change-Id: I33cd7e4040966261c2f2eb3d32f29936aeb7f632
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick a12aad6b47 all: convert more code to use net/netip directly
perl -i -npe 's,netaddr.IPPrefixFrom,netip.PrefixFrom,' $(git grep -l -F netaddr.)
    perl -i -npe 's,netaddr.IPPortFrom,netip.AddrPortFrom,' $(git grep -l -F netaddr. )
    perl -i -npe 's,netaddr.IPPrefix,netip.Prefix,g' $(git grep -l -F netaddr. )
    perl -i -npe 's,netaddr.IPPort,netip.AddrPort,g' $(git grep -l -F netaddr. )
    perl -i -npe 's,netaddr.IP\b,netip.Addr,g' $(git grep -l -F netaddr. )
    perl -i -npe 's,netaddr.IPv6Raw\b,netip.AddrFrom16,g' $(git grep -l -F netaddr. )
    goimports -w .

Then delete some stuff from the net/netaddr shim package which is no
longer neeed.

Updates #5162

Change-Id: Ia7a86893fe21c7e3ee1ec823e8aba288d4566cd8
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 6a396731eb all: use various net/netip parse funcs directly
Mechanical change with perl+goimports.

Changed {Must,}Parse{IP,IPPrefix,IPPort} to their netip variants, then
goimports -d .

Finally, removed the net/netaddr wrappers, to prevent future use.

Updates #5162

Change-Id: I59c0e38b5fbca5a935d701645789cddf3d7863ad
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 7eaf5e509f net/netaddr: start migrating to net/netip via new netaddr adapter package
Updates #5162

Change-Id: Id7bdec303b25471f69d542f8ce43805328d56c12
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 2a22ea3e83 util/deephash: generate type-specific hasher funcs
name                old time/op    new time/op    delta
Hash-8                71.1µs ± 2%    71.5µs ± 1%     ~     (p=0.114 n=9+8)
HashPacketFilter-8    8.39µs ± 1%    4.83µs ± 2%  -42.38%  (p=0.000 n=8+9)
HashMapAcyclic-8      56.2µs ± 1%    56.9µs ± 2%   +1.17%  (p=0.035 n=10+9)
TailcfgNode-8         6.49µs ± 2%    3.54µs ± 1%  -45.37%  (p=0.000 n=9+9)
HashArray-8            729ns ± 2%     566ns ± 3%  -22.30%  (p=0.000 n=10+10)

name                old alloc/op   new alloc/op   delta
Hash-8                 24.0B ± 0%     24.0B ± 0%     ~     (all equal)
HashPacketFilter-8     24.0B ± 0%     24.0B ± 0%     ~     (all equal)
HashMapAcyclic-8       0.00B          0.00B          ~     (all equal)
TailcfgNode-8          0.00B          0.00B          ~     (all equal)
HashArray-8            0.00B          0.00B          ~     (all equal)

name                old allocs/op  new allocs/op  delta
Hash-8                  1.00 ± 0%      1.00 ± 0%     ~     (all equal)
HashPacketFilter-8      1.00 ± 0%      1.00 ± 0%     ~     (all equal)
HashMapAcyclic-8        0.00           0.00          ~     (all equal)
TailcfgNode-8           0.00           0.00          ~     (all equal)
HashArray-8             0.00           0.00          ~     (all equal)

Change-Id: I34c4e786e748fe60280646d40cc63a2adb2ea6fe
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Mihai Parparita e37167b3ef ipn/localapi: add API for uploading client metrics
Clients may have platform-specific metrics they would like uploaded
(e.g. extracted from MetricKit on iOS). Add a new local API endpoint
that allows metrics to be updated by a simple name/value JSON-encoded
struct.

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Brad Fitzpatrick 6b71568eb7 util/cloudenv: add Azure support & DNS IPs
And rewrite cloud detection to try to do only zero or one metadata
discovery request for all clouds, only doing a first (or second) as
confidence increases. Work remains for Windows, but a start.

And add Cloud to tailcfg.Hostinfo, which helped with testing using
"tailcfg debug hostinfo".

Updates #4983 (Linux only)
Updates #4984

Change-Id: Ib03337089122ce0cb38c34f724ba4b4812bc614e
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick aa37aece9c ipn/ipnlocal, net/dns*, util/cloudenv: add AWS DNS support
And remove the GCP special-casing from ipn/ipnlocal; do it only in the
forwarder for *.internal.

Fixes #4980
Fixes #4981

Change-Id: I5c481e96d91f3d51d274a80fbd37c38f16dfa5cb
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 88c2afd1e3 ipn/ipnlocal, net/dns*, util/cloudenv: specialize DNS config on Google Cloud
This does three things:

* If you're on GCP, it adds a *.internal DNS split route to the
  metadata server, so we never break GCP DNS names. This lets people
  have some Tailscale nodes on GCP and some not (e.g. laptops at home)
  without having to add a Tailnet-wide *.internal DNS route.
  If you already have such a route, though, it won't overwrite it.

* If the 100.100.100.100 DNS forwarder has nowhere to forward to,
  it forwards it to the GCP metadata IP, which forwards to 8.8.8.8.
  This means there are never errNoUpstreams ("upstream nameservers not set")
  errors on GCP due to e.g. mangled /etc/resolv.conf (GCP default VMs
  don't have systemd-resolved, so it's likely a DNS supremacy fight)

* makes the DNS fallback mechanism use the GCP metadata IP as a
  fallback before our hosted HTTP-based fallbacks

I created a default GCP VM from their web wizard. It has no
systemd-resolved.

I then made its /etc/resolv.conf be empty and deleted its GCP
hostnames in /etc/hosts.

I then logged in to a tailnet with no global DNS settings.

With this, tailscaled writes /etc/resolv.conf (direct mode, as no
systemd-resolved) and sets it to 100.100.100.100, which then has
regular DNS via the metadata IP and *.internal DNS via the metadata IP
as well. If the tailnet configures explicit DNS servers, those are used
instead, except for *.internal.

This also adds a new util/cloudenv package based on version/distro
where the cloud type is only detected once. We'll likely expand it in
the future for other clouds, doing variants of this change for other
popular cloud environments.

Fixes #4911

RELNOTES=Google Cloud DNS improvements

Change-Id: I19f3c2075983669b2b2c0f29a548da8de373c7cf
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 35782f891d util/deephash: add canMemHash func + typeInfo property
Currently unused. (breaking up a bigger change)

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 7b9a901489 util/deephash: add packet filter benchmark
(breaking up parts of another change)

This adds a PacketFilter hashing benchmark with an input that both
contains every possible field, but also is somewhat representative in
the shape of what real packet filters contain.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 8c5c87be26 util/deephash: fix collisions between different types
Updates #4883

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 59ed846277 util/singleflight: add fork of singleflight with generics
Forked from golang.org/x/sync/singleflight at
the x/sync repo's commit 67f06af15bc961c363a7260195bcd53487529a21

Updates golang/go#53427

Change-Id: Iec2b47b7777940017bb9b3db9bd7d93ba4a2e394
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 757ecf7e80 util/deephash: fix map hashing when key & element have the same type
Regression from 09afb8e35b, in which the
same reflect.Value scratch value was being used as the map iterator
copy destination.

Also: make nil and empty maps hash differently, add test.

Fixes #4871

Co-authored-by: Josh Bleecher Snyder <josharian@gmail.com>
Change-Id: I67f42524bc81f694c1b7259d6682200125ea4a66
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick f31588786f util/deephash: don't track cycles on non-recursive types
name              old time/op    new time/op    delta
Hash-8              67.3µs ±20%    76.5µs ±16%     ~     (p=0.143 n=10+10)
HashMapAcyclic-8    63.0µs ± 2%    56.3µs ± 1%  -10.65%  (p=0.000 n=10+8)
TailcfgNode-8       9.18µs ± 2%    6.52µs ± 3%  -28.96%  (p=0.000 n=9+10)
HashArray-8          732ns ± 3%     709ns ± 1%   -3.21%  (p=0.000 n=10+10)

name              old alloc/op   new alloc/op   delta
Hash-8               24.0B ± 0%     24.0B ± 0%     ~     (all equal)
HashMapAcyclic-8     0.00B          0.00B          ~     (all equal)
TailcfgNode-8        0.00B          0.00B          ~     (all equal)
HashArray-8          0.00B          0.00B          ~     (all equal)

name              old allocs/op  new allocs/op  delta
Hash-8                1.00 ± 0%      1.00 ± 0%     ~     (all equal)
HashMapAcyclic-8      0.00           0.00          ~     (all equal)
TailcfgNode-8         0.00           0.00          ~     (all equal)
HashArray-8           0.00           0.00          ~     (all equal)

Change-Id: I28642050d837dff66b2db54b2b0e6d272a930be8
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 36ea837736 util/deephash: fix map hashing to actually hash elements
Fixes #4868

Change-Id: I574fd139cb7f7033dd93527344e6aa0e625477c7
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Aaron Klotz b005b79236 net/dns, paths, util/winutil: change net/dns/windowsManager NRPT management to support more than 50 domains.
AFAICT this isn't documented on MSDN, but based on the issue referenced below,
NRPT rules are not working when a rule specifies > 50 domains.

This patch modifies our NRPT rule generator to split the list of domains
into chunks as necessary, and write a separate rule for each chunk.

For compatibility reasons, we continue to use the hard-coded rule ID, but
as additional rules are required, we generate new GUIDs. Those GUIDs are
stored under the Tailscale registry path so that we know which rules are ours.

I made some changes to winutils to add additional helper functions in support
of both the code and its test: I added additional registry accessors, and also
moved some token accessors from paths to util/winutil.

Fixes https://github.com/tailscale/coral/issues/63

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2 years ago
Aaron Klotz c163b2a3f1 util/winutil, util/winutil/vss: remove winrestore and vss as they are unnecessary.
I wrote this code way back at the beginning of my tenure at Tailscale when we
had concerns about needing to restore deleted machine keys from backups.

We never ended up using this functionality, and the code is now getting in the
way, so we might as well remove it.

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2 years ago
Mihai Parparita dd5548771e util/clientmetric: add gauge_ name prefix when uploading names
The prefix is a signal to tsweb to treat this as a gauge metric when
generating the Prometheus version.

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Maisem Ali fd99c54e10 tailcfg,all: change structs to []*dnstype.Resolver
Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Maisem Ali e409e59a54 cmd/cloner,util/codegen: refactor cloner internals to allow reuse
Also run go generate again for Copyright updates.

Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Mihai Parparita 025867fd07
util/clientmetric: switch to TestHooks struct for test-only functions (#4632)
Followup to 7966aed1e0 to pick up
review feedback that was accidentally left out.

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Mihai Parparita 7966aed1e0
util/clientmetric: add test hooks and ResetLastDelta function
Necessary to force flushing of client metrics more aggressively in
dev/test mode.

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Brad Fitzpatrick 373176ea54 util/codegen: format generated code with goimports, not gofmt
goimports is a superset of gofmt that also groups imports.
(the goimports tool also adds/removes imports as needed, but that
part is disabled here)

Change-Id: Iacf0408dfd9497f4ed3da4fa50e165359ce38498
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 910ae68e0b util/mak: move tailssh's mapSet into a new package for reuse elsewhere
Change-Id: Idfe95db82275fd2be6ca88f245830731a0d5aecf
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 53588f632d Revert "wgengine/router,util/kmod: load & log xt_mark"
This reverts commit 8d6793fd70.

Reason: breaks Android build (cgo/pthreads addition)

We can try again next cycle.

Change-Id: I5e7e1730a8bf399a8acfce546a6d22e11fb835d5
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
James Tucker 8d6793fd70 wgengine/router,util/kmod: load & log xt_mark
Attempt to load the xt_mark kernel module when it is not present. If the
load fails, log error information.

It may be tempting to promote this failure to an error once it has been
in use for some time, so as to avoid reaching an error with the iptables
invocation, however, there are conditions under which the two stages may
disagree - this change adds more useful breadcrumbs.

Example new output from tailscaled running under my WSL2:

```
router: ensure module xt_mark: "/usr/sbin/modprobe xt_mark" failed: exit status 1; modprobe: FATAL: Module xt_mark not found in directory /lib/modules/5.10.43.3-microsoft-standard-WSL2
```

Background:

There are two places to lookup modules, one is `/proc/modules` "old",
the other is `/sys/module/` "new".

There was query_modules(2) in linux <2.6, alas, it is gone.

In a docker container in the default configuration, you would get
/proc/modules and /sys/module/ both populated. lsmod may work file,
modprobe will fail with EPERM at `finit_module()` for an unpriviliged
container.

In a priviliged container the load may *succeed*, if some conditions are
met. This condition should be avoided, but the code landing in this
change does not attempt to avoid this scenario as it is both difficult
to detect, and has a very uncertain impact.

In an nspawn container `/proc/modules` is populated, but `/sys/module`
does not exist. Modern `lsmod` versions will fail to gather most module
information, without sysfs being populated with module information.

In WSL2 modules are likely missing, as the in-use kernel typically is
not provided by the distribution filesystem, and WSL does not mount in a
module filesystem of its own. Notably the WSL2 kernel supports iptables
marks without listing the xt_mark module in /sys/module, and
/proc/modules is empty.

On a recent kernel, we can ask the capabilities system about SYS_MODULE,
that will help to disambiguate between the non-privileged container case
and just being root. On older kernels these calls may fail.

Update #4329

Signed-off-by: James Tucker <james@tailscale.com>
2 years ago
Maisem Ali 909f40da84
util/groupmember: remove redundant code (#4298)
Now that we have 30faf968b1
this is no longer needed.

Fixes #3001

Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Josh Bleecher Snyder 32fd42430b all: use cibuild.On
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
2 years ago
Josh Bleecher Snyder 0868329936 all: use any instead of interface{}
My favorite part of generics.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
2 years ago
Brad Fitzpatrick 61ee72940c all: use Go 1.18's strings.Cut
More remain.

Change-Id: I6ec562cc1f687600758deae1c9d7dbd0d04004cb
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Josh Bleecher Snyder 97a01b7b17 util/deephash: remove Tailscale toolchain compatibility shim
The future is now.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
2 years ago
Josh Bleecher Snyder 463728a885 util/netconv: add package to convert between netip and netaddr types
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
2 years ago
Aaron Klotz 82cd98609f util/winutil: migrate corp's winutil into OSS.
It makes the most sense to have all our utility functions reside in one place.
There was nothing in corp that could not reasonably live in OSS.

I also updated `StartProcessAsChild` to no longer depend on `futureexec`,
thus reducing the amount of code that needed migration. I tested this change
with `tswin` and it is working correctly.

I have a follow-up PR to remove the corresponding code from corp.

The migrated code was mostly written by @alexbrainman.
Sourced from corp revision 03e90cfcc4dd7b8bc9b25eb13a26ec3a24ae0ef9

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2 years ago
Aaron Klotz 3a74f2d2d7 cmd/tailscaled, util/winutil: add accessor functions for Windows system policies.
This patch adds new functions to be used when accessing system policies,
and revises callers to use the new functions. They first attempt the new
registry path for policies, and if that fails, attempt to fall back to the
legacy path.

We keep non-policy variants of these functions because we should be able to
retain the ability to read settings from locations that are not exposed to
sysadmins for group policy edits.

The remaining changes will be done in corp.

Updates https://github.com/tailscale/tailscale/issues/3584

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2 years ago
Brad Fitzpatrick 0626cf4183 util/winutil: fix build
It was broken on Windows:

Error: util\winutil\winutil_windows.go:15:7: regBase redeclared in this block
Error:                                       D:\a\tailscale\tailscale\util\winutil\winutil_notwindows.go:7:17: previous declaration
Error: util\winutil\winutil_windows.go:29:6: getRegString redeclared in this block
Error:                                       D:\a\tailscale\tailscale\util\winutil\winutil_notwindows.go:9:40: previous declaration
Error: util\winutil\winutil_windows.go:47:6: getRegInteger redeclared in this block
Error:                                       D:\a\tailscale\tailscale\util\winutil\winutil_notwindows.go:11:48: previous declaration
Error: util\winutil\winutil_windows.go:77:6: isSIDValidPrincipal redeclared in this block
Error:                                       D:\a\tailscale\tailscale\util\winutil\winutil_notwindows.go:13:38: previous declaration

Change-Id: Ib1ce4b647f5711547840c736b933a6c42bf09583
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Aaron Klotz d7962e3bcf ipn/ipnserver, util/winutil: update workaround for os/user.LookupId failures on Windows to reject SIDs from deleted/invalid security principals.
Our current workaround made the user check too lax, thus allowing deleted
users. This patch adds a helper function to winutil that checks that the
uid's SID represents a valid Windows security principal.

Now if `lookupUserFromID` determines that the SID is invalid, we simply
propagate the error.

Updates https://github.com/tailscale/tailscale/issues/869

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2 years ago
Brad Fitzpatrick 486059589b all: gofmt -w -s (simplify) tests
And it updates the build tag style on a couple files.

Change-Id: I84478d822c8de3f84b56fa1176c99d2ea5083237
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 0de1b74fbb util/clientmetric: add tests omitted from earlier commit
These were supposed to be part of
3b541c833e but I guess I forgot to "git
add" them. Whoops.

Updates #3307

Change-Id: I8c768a61ec7102a01799e81dc502a22399b9e9f0
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 5b5f032c9a util/clientmetric: optimize memory layout for finding updates
Updates #3307

Change-Id: I2840b190583467cc3f00688b96ce3d170df46a46
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 3b541c833e util/clientmetric, logtail: log metric changes
Updates #3307

Change-Id: I1399ebd786f6ff7defe6e11c0eb651144c071574
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 57b039c51d util/clientmetrics: add new package to add metrics to the client
And annotate magicsock as a start.

And add localapi and debug handlers with the Prometheus-format
exporter.

Updates #3307

Change-Id: I47c5d535fe54424741df143d052760387248f8d3
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
David Anderson 0532eb30db all: replace tailcfg.DiscoKey with key.DiscoPublic.
Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
Josh Bleecher Snyder 3fd5f4380f util/multierr: new package
github.com/go-multierror/multierror served us well.
But we need a few feature from it (implement Is),
and it's not worth maintaining a fork of such a small module.

Instead, I did a clean room implementation inspired by its API.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
David Anderson a9c78910bd wgengine/wgcfg: convert to use new node key type.
Updates #3206

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
Aaron Klotz c6ea282b3f utils/winutil utils/winutil/vss: add utility function for extracting data from Windows System Restore Point backups.
utils/winutil/vss contains just enough COM wrapping to query the Volume Shadow Copy service for snapshots.
WalkSnapshotsForLegacyStateDir is the friendlier interface that adds awareness of our actual use case,
mapping the snapshots and locating our legacy state directory.

Updates #3011

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
3 years ago
Brad Fitzpatrick 0410f1a35a util/groupmember: adjust build tags for osusergo
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 2a0d3f72c5 util/groupmember: fix typo of package's name in its package doc
And canonicalize a func comment while I'm here.

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Aaron Klotz 3386a86fe5 util/winutil: add GetRegInteger
This helper allows us to retrieve `DWORD` and `QWORD` values from the Tailscale key in the Windows registry.

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
3 years ago
Josh Bleecher Snyder b14db5d943 util/codegen: reorder AssertStructUnchanged args
The fully qualified name of the type is thisPkg.tname,
so write the args like that too.

Suggested-by: Joe Tsai <joetsai@digital-static.net>
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder 3cd85c0ca6 util/codegen: add ContainsPointers
And use it in cmd/cloner.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder d8a8f70000 util/codegen: add NamedTypes
And use it in cmd/cloner.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder 618376dbc0 util/codegen: add AssertStructUnchanged
Refactored out from cmd/cloner.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder fb66ff7c78 util/codegen: add package
This is a package for shared utilities used in doing codegen programs.
The inaugural API is for writing gofmt'd code to a file.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
David Anderson bb10443edf wgengine/wgcfg: use just the hexlified node key as the WireGuard endpoint.
The node key is all magicsock needs to find the endpoint that WireGuard
needs.

Updates #2752

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
David Anderson 54bc3b7d97 util/deephash: remove soon to be deleted field from wgcfg.
Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
Joe Tsai 3f1317e3e5
util/deephash: fix TestArrayAllocs
Unfortunately this test fails on certain architectures.
The problem comes down to inconsistencies in the Go escape analysis
where specific variables are marked as escaping on certain architectures.
The variables escaping to the heap are unfortunately in crypto/sha256,
which makes it impossible to fixthis locally in deephash.

For now, fix the test by compensating for the allocations that
occur from calling sha256.digest.Sum.

See golang/go#48055

Fixes #2727

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
3 years ago
slowy07 ac0353e982 fix: typo spelling grammar
Signed-off-by: slowy07 <slowy.arfy@gmail.com>
3 years ago
David Crawshaw 360223fccb types/dnstype: introduce new package for Resolver
So the type can be used in net/dns without introducing a tailcfg
dependency.

For #2596

Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
3 years ago
Josh Bleecher Snyder a5da4ed981 all: gofmt with Go 1.17
This adds "//go:build" lines and tidies up existing "// +build" lines.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Joe Tsai 9d0c86b6ec
util/deephash: remove unnecessary formatting for structs and slices (#2571)
The index for every struct field or slice element and
the number of fields for the struct is unncessary.

The hashing of Go values is unambiguous because every type (except maps)
encodes in a parsable manner. So long as we know the type information,
we could theoretically decode every value (except for maps).

At a high level:
* numbers are encoded as fixed-width records according to precision.
* strings (and AppendTo output) are encoded with a fixed-width length,
followed by the contents of the buffer.
* slices are prefixed by a fixed-width length, followed by the encoding
of each value. So long as we know the type of each element, we could
theoretically decode each element.
* arrays are encoded just like slices, but elide the length
since it is determined from the Go type.
* maps are encoded first with a byte indicating whether it is a cycle.
If a cycle, it is followed by a fixed-width index for the pointer,
otherwise followed by the SHA-256 hash of its contents. The encoding of maps
is not decodeable, but a SHA-256 hash is sufficient to avoid ambiguities.
* interfaces are encoded first with a byte indicating whether it is nil.
If not nil, it is followed by a fixed-width index for the type,
and then the encoding for the underlying value. Having the type be encoded
first ensures that the value could theoretically be decoded next.
* pointers are encoded first with a byte indicating whether it is
1) nil, 2) a cycle, or 3) newly seen. If a cycle, it is followed by
a fixed-width index for the pointer. If newly seen, it is followed by
the encoding for the pointed-at value.

Removing unnecessary details speeds up hashing:

	name              old time/op    new time/op    delta
	Hash-8              76.0µs ± 1%    55.8µs ± 2%  -26.62%        (p=0.000 n=10+10)
	HashMapAcyclic-8    61.9µs ± 0%    62.0µs ± 0%     ~             (p=0.666 n=9+9)
	TailcfgNode-8       10.2µs ± 1%     7.5µs ± 1%  -26.90%         (p=0.000 n=10+9)
	HashArray-8         1.07µs ± 1%    0.70µs ± 1%  -34.67%         (p=0.000 n=10+9)

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
3 years ago
Joe Tsai d8fbce7eef
util/deephash: hash uint{8,16,32,64} explicitly (#2502)
Instead of hashing the humanly formatted forms of a number,
hash the native machine bits of the integers themselves.

There is a small performance gain for this:
	name              old time/op    new time/op    delta
	Hash-8              75.7µs ± 1%    76.0µs ± 2%    ~            (p=0.315 n=10+9)
	HashMapAcyclic-8    63.1µs ± 3%    61.3µs ± 1%  -2.77%        (p=0.000 n=10+10)
	TailcfgNode-8       10.3µs ± 1%    10.2µs ± 1%  -1.48%        (p=0.000 n=10+10)
	HashArray-8         1.07µs ± 1%    1.05µs ± 1%  -1.79%        (p=0.000 n=10+10)

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
3 years ago
Joe Tsai 01d4dd331d
util/deephash: simplify hasher.hashMap (#2503)
The swapping of bufio.Writer between hasher and mapHasher is subtle.
Just embed a hasher in mapHasher to avoid complexity here.

No notable change in performance:
	name              old time/op    new time/op    delta
	Hash-8              76.7µs ± 1%    77.0µs ± 1%    ~            (p=0.182 n=9+10)
	HashMapAcyclic-8    62.4µs ± 1%    62.5µs ± 1%    ~            (p=0.315 n=10+9)
	TailcfgNode-8       10.3µs ± 1%    10.3µs ± 1%  -0.62%         (p=0.004 n=10+9)
	HashArray-8         1.07µs ± 1%    1.06µs ± 1%  -0.98%          (p=0.001 n=8+9)

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
3 years ago
Joe Tsai d145c594ad
util/deephash: improve cycle detection (#2470)
The previous algorithm used a map of all visited pointers.
The strength of this approach is that it quickly prunes any nodes
that we have ever visited before. The detriment of the approach
is that pruning is heavily dependent on the order that pointers
were visited. This is especially relevant for hashing a map
where map entries are visited in a non-deterministic manner,
which would cause the map hash to be non-deterministic
(which defeats the point of a hash).

This new algorithm uses a stack of all visited pointers,
similar to how github.com/google/go-cmp performs cycle detection.
When we visit a pointer, we push it onto the stack, and when
we leave a pointer, we pop it from the stack.
Before visiting a pointer, we first check whether the pointer exists
anywhere in the stack. If yes, then we prune the node.
The detriment of this approach is that we may hash a node more often
than before since we do not prune as aggressively.

The set of visited pointers up until any node is only the
path of nodes up to that node and not any other pointers
that may have been visited elsewhere. This provides us
deterministic hashing regardless of visit order.
We can now delete hashMapFallback and associated complexity,
which only exists because the previous approach was non-deterministic
in the presence of cycles.

This fixes a failure of the old algorithm where obviously different
values are treated as equal because the pruning was too aggresive.
See https://github.com/tailscale/tailscale/issues/2443#issuecomment-883653534

The new algorithm is slightly slower since it prunes less aggresively:
	name              old time/op    new time/op    delta
	Hash-8              66.1µs ± 1%    68.8µs ± 1%   +4.09%        (p=0.000 n=19+19)
	HashMapAcyclic-8    63.0µs ± 1%    62.5µs ± 1%   -0.76%        (p=0.000 n=18+19)
	TailcfgNode-8       9.79µs ± 2%    9.88µs ± 1%   +0.95%        (p=0.000 n=19+17)
	HashArray-8          643ns ± 1%     653ns ± 1%   +1.64%        (p=0.000 n=19+19)
However, a slower but more correct algorithm seems
more favorable than a faster but incorrect algorithm.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
3 years ago
Joe Tsai d666bd8533
util/deephash: disambiguate hashing of AppendTo (#2483)
Prepend size to AppendTo output.

Fixes #2443

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
3 years ago
Joe Tsai 23ad028414
util/deephash: include type as part of hash for interfaces (#2476)
A Go interface may hold any number of different concrete types.
Just because two underlying values hash to the same thing
does not mean the two values are identical if they have different
concrete types. As such, include the type in the hash.
3 years ago
Joe Tsai a5fb8e0731
util/deephash: introduce deliberate instability (#2477)
Seed the hash upon first use with the current time.
This ensures that the stability of the hash is bounded within
the lifetime of one program execution.
Hopefully, this prevents future bugs where someone assumes that
this hash is stable.

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
3 years ago
Joe Tsai 9a0c8bdd20 util/deephash: make hash type opaque
The fact that Hash returns a [sha256.Size]byte leaks details about
the underlying hash implementation. This could very well be any other
hashing algorithm with a possible different block size.

Abstract this implementation detail away by declaring an opaque type
that is comparable. While we are changing the signature of UpdateHash,
rename it to just Update to reduce stutter (e.g., deephash.Update).

Signed-off-by: Joe Tsai <joetsai@digital-static.net>
3 years ago
Brad Fitzpatrick ddb8726c98 util/deephash: don't reflect.Copy if element type is a defined uint8
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick df176c82f5 util/deephash: skip alloc test under race detector
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 6dc38ff25c util/deephash: optimize hashing of byte arrays, reduce allocs in Hash
name              old time/op    new time/op    delta
Hash-6               173µs ± 4%     101µs ± 3%   -41.69%  (p=0.000 n=10+9)
HashMapAcyclic-6     101µs ± 5%     105µs ± 3%    +3.52%  (p=0.001 n=9+10)
TailcfgNode-6       29.4µs ± 2%    16.4µs ± 3%   -44.25%  (p=0.000 n=8+10)

name              old alloc/op   new alloc/op   delta
Hash-6              3.60kB ± 0%    1.13kB ± 0%   -68.70%  (p=0.000 n=10+10)
HashMapAcyclic-6    2.53kB ± 0%    2.53kB ± 0%      ~     (p=0.137 n=10+8)
TailcfgNode-6         528B ± 0%        0B       -100.00%  (p=0.000 n=10+10)

name              old allocs/op  new allocs/op  delta
Hash-6                84.0 ± 0%      40.0 ± 0%   -52.38%  (p=0.000 n=10+10)
HashMapAcyclic-6       202 ± 0%       202 ± 0%      ~     (all equal)
TailcfgNode-6         11.0 ± 0%       0.0       -100.00%  (p=0.000 n=10+10)

Updates tailscale/corp#2130

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 3962744450 util/deephash: prevent infinite loop on map cycle
Fixes #2340

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick aceaa70b16 util/deephash: move funcs to methods
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 14f901da6d util/deephash: fix sync.Pool usage
Whoops.

From yesterday's 9ae3bd0939 (not yet
used by anything, fortunately)

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick e0258ffd92 util/deephash: use keyed struct literal, fix vet
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago