Commit Graph
97 Commits
Author SHA1 Message Date
Aaron Klotz 84472167dd tool/gocross: fix environment variable clearing in gocross-wrapper.ps1
The -Environment argument to Start-Process is essentially being treated
as a delta; removing a particular variable from the argument's hash
table does not indicate to delete. Instead we must set the value of each
unwanted variable to $null.

Updates https://github.com/tailscale/corp/issues/29940

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2025-08-18 15:34:50 -06:00
Aaron Klotz d92789affa tool/gocross: don't set executable bits on PowerShell script
Updates https://github.com/tailscale/corp/issues/29940

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2025-08-18 14:40:21 -06:00
Aaron Klotz 02f6030dbd tool, tool/gocross: update gocross to support building natively on Windows and add a PowerShell Core wrapper script
gocross-wrapper.ps1 is a PowerShell core script that is essentially a
straight port of gocross-wrapper.sh. It requires PowerShell 7.4, which
is the latest LTS release of PSCore.

Why use PowerShell Core instead of Windows PowerShell? Essentially
because the former is much better to script with and is the edition
that is currently maintained.

Because we're using PowerShell Core, but many people will be running
scripts from a machine that only has Windows PowerShell, go.cmd has
been updated to prompt the user for PowerShell core installation if
necessary.

gocross-wrapper.sh has also been updated to utilize the PSCore script
when running under cygwin or msys.

gocross itself required a couple of updates:

We update gocross to output the PowerShell Core wrapper alongside the
bash wrapper, which will propagate the revised scripts to other repos
as necessary.

We also fix a couple of things in gocross that didn't work on Windows:
we change the toolchain resolution code to use os.UserHomeDir instead
of directly referencing the HOME environment variable, and we fix a
bug in the way arguments were being passed into exec.Command on
non-Unix systems.

Updates https://github.com/tailscale/corp/issues/29940

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2025-08-18 09:49:24 -06:00
Aaron Klotz bfebf870ae cmd/tailscaled: update installSystemDaemonWindows to set the correct system service depndencies
Fixes #16658

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2025-07-25 11:03:57 -06:00
Aaron Klotz 2a5d9c7269 VERSION.txt: this is v1.87.0
Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2025-07-24 12:25:57 -06:00
Aaron Klotz 13e91f4a2f docs/windows/policy: add OnboardingFlow policy to ADMX file
Fixes #15907

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2025-05-12 12:39:44 -06:00
Aaron Klotz 7d73a38b40 net/dns: only populate OSConfig.Hosts when MagicDNS is enabled
Previously we were doing this unconditionally.

Updates #14428

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2025-01-16 10:23:59 -05:00
Aaron Klotz fcf90260ce atomicfile: use ReplaceFile on Windows so that attributes and ACLs are preserved
I moved the actual rename into separate, GOOS-specific files. On
non-Windows, we do a simple os.Rename. On Windows, we first try
ReplaceFile with a fallback to os.Rename if the target file does
not exist.

ReplaceFile is the recommended way to rename the file in this use case,
as it preserves attributes and ACLs set on the target file.

Updates #14428

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2025-01-15 13:57:37 -05:00
Aaron Klotz d818a58a77 net/dns: ensure the Windows configurator does not touch the hosts file unless the configuration actually changed
We build up maps of both the existing MagicDNS configuration in hosts
and the desired MagicDNS configuration, compare the two, and only
write out a new one if there are changes. The comparison doesn't need
to be perfect, as the occasional false-positive is fine, but this
should greatly reduce rewrites of the hosts file.

I also changed the hosts updating code to remove the CRLF/LF conversion
stuff, and use Fprintf instead of Frintln to let us write those inline.

Updates #14428

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2025-01-14 16:37:35 -05:00
Aaron Klotz 48343ee673 util/winutil/s4u: fix token handle leak
Fixes #14156

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-11-19 14:11:50 -05:00
Aaron Klotz 84c8860472 util/syspolicy: add policy key for onboarding flow visibility
Updates https://github.com/tailscale/corp/issues/23789

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-10-31 15:46:40 -06:00
Aaron Klotz 8f6a2353d8 util/winutil: add GetRegUserString/SetRegUserString accessors for storage and retrieval of string values in HKEY_CURRENT_USER
Fixes #13187

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-08-20 08:07:57 -06:00
Aaron Klotz f95785f22b util/winutil: add constants from Win32 SDK for dll blocking mitigation policies
Fixes #13182

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-08-19 13:33:48 -06:00
Aaron Klotz 655b4f8fc5 net/netns: remove some logspam by avoiding logging parse errors due to unspecified addresses
I updated the address parsing stuff to return a specific error for
unspecified hosts passed as empty strings, and look for that
when logging errors. I explicitly did not make parseAddress return a
netip.Addr containing an unspecified address because at this layer,
in the absence of any host, we don't necessarily know the address
family we're dealing with.

For the purposes of this code I think this is fine, at least until
we implement #12588.

Fixes #12979

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-07-31 12:34:16 -06:00
Aaron Klotz 0def4f8e38 net/netns: on Windows, fall back to default interface index when unspecified address is passed to ControlC and bindToInterfaceByRoute is enabled
We were returning an error instead of binding to the default interface.

Updates #12979

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-07-31 10:58:45 -06:00
Aaron Klotz 4ff276cf52 VERSION.txt: this is v1.71.0
Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-07-17 11:27:05 -06:00
Aaron Klotz e181f12a7b util/winutil/s4u: fix some doc comments in the s4u package
This is #cleanup

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-07-05 13:19:47 -07:00
Aaron Klotz b292f7f9ac util/winutil/s4u: fix incorrect token type specified in s4u Login
This was correct before, I think I just made a copy/paste error when
updating that PR.

Updates #12383

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-06-26 14:28:56 -06:00
Aaron Klotz 5f177090e3 util/winutil: ensure domain controller address is used when retrieving remote profile information
We cannot directly pass a flat domain name into NetUserGetInfo; we must
resolve the address of a domain controller first.

This PR implements the appropriate resolution mechanisms to do that, and
also exposes a couple of new utility APIs for future needs.

Fixes #12627

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-06-26 13:10:10 -06:00
Aaron Klotz da078b4c09 util/winutil: add package for logging into Windows via Service-for-User (S4U)
This PR ties together pseudoconsoles, user profiles, s4u logons, and
process creation into what is (hopefully) a simple API for various
Tailscale services to obtain Windows access tokens without requiring
knowledge of any Windows passwords. It works both for domain-joined
machines (Kerberos) and non-domain-joined machines. The former case
is fairly straightforward as it is fully documented. OTOH, the latter
case is not documented, though it is fully defined in the C headers in
the Windows SDK. The documentation blanks were filled in by reading
the source code of Microsoft's Win32 port of OpenSSH.

We need to do a bit of acrobatics to make conpty work correctly while
creating a child process with an s4u token; see the doc comments above
startProcessInternal for details.

Updates #12383

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-06-25 22:05:52 -06:00
Aaron Klotz 7dd76c3411 net/netns: add Windows support for bind-to-interface-by-route
This is implemented via GetBestInterfaceEx. Should we encounter errors
or fail to resolve a valid, non-Tailscale interface, we fall back to
returning the index for the default interface instead.

Fixes #12551

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-06-24 10:43:34 -06:00
Aaron Klotz d7a4f9d31c net/dns: ensure multiple hosts with the same IP address are combined into a single HostEntry
This ensures that each line has a unique IP address.

Fixes #11939

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-06-21 13:16:49 -06:00
Aaron Klotz 2cb408f9b1 hostinfo: update Windows hostinfo to include MSIDist registry value
We need to expand our enviornment information to include info about
the Windows store. Thinking about future plans, it would be nice
to include both the packaging mechanism and the distribution mechanism.

In this PR we change packageTypeWindows to check a new registry value
named MSIDist, and concatenate that value to "msi/" when present.

We also remove vestigial NSIS detection.

Updates https://github.com/tailscale/corp/issues/2790

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-06-18 10:19:00 -06:00
Aaron Klotz 7354547bd8 util/winutil: update UserProfile to ensure any environment variables in the roaming profile path are expanded
Updates #12383

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-06-14 13:01:01 -06:00
Aaron Klotz bd2a6d5386 util/winutil: add UserProfile type for (un)loading user profiles
S4U logons do not automatically load the associated user profile. In this
PR we add UserProfile to handle that part. Windows docs indicate that
we should try to resolve a remote profile path when present, so we attempt
to do so when the local computer is joined to a domain.

Updates #12383

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-06-14 11:02:01 -06:00
Aaron Klotz 3511d1f8a2 cmd/tailscaled, net/dns, wgengine/router: start Windows child processes with DETACHED_PROCESS when I/O is being piped
When we're starting child processes on Windows that are CLI programs that
don't need to output to a console, we should pass in DETACHED_PROCESS as a
CreationFlag on SysProcAttr. This prevents the OS from even creating a console
for the child (and paying the associated time/space penalty for new conhost
processes). This is more efficient than letting the OS create the console
window and then subsequently trying to hide it, which we were doing at a few
callsites.

Fixes #12270

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-06-11 11:35:26 -06:00
Aaron Klotz df86576989 util/winutil: add AllocateContiguousBuffer and SetNTString helper funcs
AllocateContiguousBuffer is for allocating structs with trailing buffers
containing additional data. It is to be used for various Windows structures
containing pointers to data located immediately after the struct.

SetNTString performs in-place setting of windows.NTString and
windows.NTUnicodeString.

Updates #12383

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-06-10 09:39:37 -06:00
Aaron Klotz 34e8820301 util/winutil: add conpty package and helper for building windows.StartupInfoEx
StartupInfoBuilder is a helper for constructing StartupInfoEx structures
featuring proc/thread attribute lists. Calling its setters triggers the
appropriate setting of fields, adjusting flags as necessary, and populating
the proc/thread attribute list as necessary. Currently it supports four
features: setting std handles, setting pseudo-consoles, specifying handles
for inheritance, and specifying jobs.

The conpty package simplifies creation of pseudo-consoles, their associated
pipes, and assignment of the pty to StartupInfoEx proc/thread attributes.

Updates #12383

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-06-06 14:18:36 -06:00
Aaron Klotz 7132b782d4 hostinfo: use Distro field for distinguishing Windows Server builds
Some editions of Windows server share the same build number as their
client counterpart; we must use an additional field found in the OS
version information to distinguish between them.

Even though "Distro" has Linux connotations, it is the most appropriate
hostinfo field. What is Windows Server if not an alternate distribution
of Windows? This PR populates Distro with "Server" when applicable.

Fixes #11785

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-04-18 13:48:50 -06:00
Aaron Klotz 4d5d669cd5 net/dns: unconditionally write NRPT rules to local settings
We were being too aggressive when deciding whether to write our NRPT rules
to the local registry key or the group policy registry key.

After once again reviewing the document which calls itself a spec
(see issue), it is clear that the presence of the DnsPolicyConfig subkey
is the important part, not the presence of values set in the DNSClient
subkey. Furthermore, a footnote indicates that the presence of
DnsPolicyConfig in the GPO key will always override its counterpart in
the local key. The implication of this is important: we may unconditionally
write our NRPT rules to the local key. We copy our rules to the policy
key only when it contains NRPT rules belonging to somebody other than us.

Fixes https://github.com/tailscale/corp/issues/19071

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-04-12 11:56:26 -06:00
Aaron Klotz f7acbefbbb wgengine/router: make the Windows ifconfig implementation reuse existing MibIPforwardRow2 when possible
Looking at profiles, we spend a lot of time in winipcfg.LUID.DeleteRoute
looking up the routing table entry for the provided RouteData.

But we already have the row! We previously obtained that data via the full
table dump we did in getInterfaceRoutes. We can make this a lot faster by
hanging onto a reference to the wipipcfg.MibIPforwardRow2 and executing
the delete operation directly on that.

Fixes #11123

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-02-13 11:17:01 -07:00
Aaron Klotz aed2cfec4e util/winutil: add some missing docs to restartmgr errors
Just a quick #cleanup.

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-01-05 10:12:08 -08:00
Aaron Klotz e32a064659 cmd/tailscaled: don't create a network monitor in the parent tailscaled on Windows
The service is only used as a watchdog and for piping logs from the child
process. We shouldn't be creating a network monitor in that case.

Fixes #10732

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2024-01-03 11:57:34 -08:00
Aaron Klotz 5812093d31 util/winutil: publicize existing functions for opening read-only connections to the Windows Service Control Manager
We're going to need to access these from code outside winutil.

Updates #10215

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-12-22 10:52:50 -08:00
Aaron Klotz 0f646937e9 clientupdate: remove TS_NOLAUNCH and GUI restart hacks from autoupdate
We've fixed the underlying issue in github.com/tailscale/corp/issues/13998.

Fixes #10513

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-12-08 10:07:45 -08:00
Aaron Klotz 64a26b221b net/dns: use an additional registry setting to disable dynamic DNS updates for our interface on Windows
Fixes #9775

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-12-04 09:10:35 -08:00
Aaron Klotz db39a43f06 util/winutil: add support for restarting Windows processes in specific sessions
This PR is all about adding functionality that will enable the installer's
upgrade sequence to terminate processes belonging to the previous version,
and then subsequently restart instances belonging to the new version within
the session(s) corresponding to the processes that were killed.

There are multiple parts to this:

* We add support for the Restart Manager APIs, which allow us to query the
  OS for a list of processes locking specific files;
* We add the RestartableProcess and RestartableProcesses types that query
  additional information about the running processes that will allow us
  to correctly restart them in the future. These types also provide the
  ability to terminate the processes.
* We add the StartProcessInSession family of APIs that permit us to create
  new processes within specific sessions. This is needed in order to
  properly attach a new GUI process to the same RDP session and desktop that
  its previously-terminated counterpart would have been running in.
* I tweaked the winutil token APIs again.
* A lot of this stuff is pretty hard to test without a very elaborate
  harness, but I added a unit test for the most complicated part (though it
  requires LocalSystem to run).

Updates https://github.com/tailscale/corp/issues/13998

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-11-30 14:04:27 -08:00
Aaron Klotz 855f79fad7 cmd/tailscaled, util/winutil: changes to process and token APIs in winutil
This PR changes the internal getTokenInfo function to use generics.
I also removed our own implementations for obtaining a token's user
and primary group in favour of calling the ones now available in
x/sys/windows.

Furthermore, I added two new functions for working with tokens, logon
session IDs, and Terminal Services / RDP session IDs.

I modified our privilege enabling code to allow enabling of multiple
privileges via one single function call.

Finally, I added the ProcessImageName function and updated the code in
tailscaled_windows.go to use that instead of directly calling the
underlying API.

All of these changes will be utilized by subsequent PRs pertaining to
this issue.

Updates https://github.com/tailscale/corp/issues/13998

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-11-15 12:07:19 -07:00
Aaron Klotz fbc18410ad ipn/ipnauth: improve the Windows token administrator check
(*Token).IsAdministrator is supposed to return true even when the user is
running with a UAC limited token. The idea is that, for the purposes of
this check, we don't care whether the user is *currently* running with
full Admin rights, we just want to know whether the user can
*potentially* do so.

We accomplish this by querying for the token's "linked token," which
should be the fully-elevated variant, and checking its group memberships.

We also switch ipn/ipnserver/(*Server).connIsLocalAdmin to use the elevation
check to preserve those semantics for tailscale serve; I want the
IsAdministrator check to be used for less sensitive things like toggling
auto-update on and off.

Fixes #10036

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-11-03 14:37:04 -06:00
Aaron Klotz 47019ce1f1 cmd/tailscaled: pre-load wintun.dll using a fully-qualified path
In corp PR #14970 I updated the installer to set a security mitigation that
always forces system32 to the front of the Windows dynamic linker's search
path.

Unfortunately there are other products out there that, partying like it's
1995, drop their own, older version of wintun.dll into system32. Since we
look there first, we end up loading that old version.

We can fix this by preloading wintun using a fully-qualified path. When
wintun-go then loads wintun, the dynamic linker will hand it the module
that was previously loaded by us.

Fixes #10023, #10025, #10052

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-11-02 09:47:21 -06:00
Aaron Klotz 95671b71a6 ipn, safesocket: use Windows token in LocalAPI
On Windows, the idiomatic way to check access on a named pipe is for
the server to impersonate the client on its current OS thread, perform
access checks using the client's access token, and then revert the OS
thread's access token back to its true self.

The access token is a better representation of the client's rights than just
a username/userid check, as it represents the client's effective rights
at connection time, which might differ from their normal rights.

This patch updates safesocket to do the aforementioned impersonation,
extract the token handle, and then revert the impersonation. We retain
the token handle for the remaining duration of the connection (the token
continues to be valid even after we have reverted back to self).

Since the token is a property of the connection, I changed ipnauth to wrap
the concrete net.Conn to include the token. I then plumbed that change
through ipnlocal, ipnserver, and localapi as necessary.

I also added a PermitLocalAdmin flag to the localapi Handler which I intend
to use for controlling access to a few new localapi endpoints intended
for configuring auto-update.

Updates https://github.com/tailscale/tailscale/issues/755

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-10-26 09:43:19 -06:00
Aaron Klotz 098d110746 VERSION.txt: this is v1.51.0
Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-09-25 10:44:02 -06:00
Aaron Klotz ea6ca78963 release/dist, tool/gocross: add fake "windowsdll" GOOS to gocross
We're going to need to build a DLL containing custom actions for the installer.
This patch adds the foundations of that capability to dist and gocross.

Updates https://github.com/tailscale/corp/issues/13998

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-09-21 13:09:36 -06:00
Aaron KlotzandAndrew Lytvynov 7686ff6c46 Update clientupdate/distsign/distsign_test.go
Co-authored-by: Andrew Lytvynov <awly@tailscale.com>
Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-09-05 15:43:36 -06:00
Aaron Klotz 7d60c19d7d clientupdate/distsign: add ability to validate a binary that is already located on disk
Our build system caches files locally and only updates them when something
changes. Since I need to integrate some distsign stuff into the build system
to validate our Windows 7 MSIs, I want to be able to check the cached copy
of a package before downloading a fresh copy from pkgs.

If the signature changes, then obviously the local copy is outdated and we
return an error, at which point we call Download to refresh the package.

Updates https://github.com/tailscale/corp/issues/14334

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-09-05 15:43:36 -06:00
Aaron Klotz 6b6a8cf843 util/osdiag: add query for Windows page file configuration and status
It's very common for OOM crashes on Windows to be caused by lack of page
file space (the NT kernel does not overcommit). Since Windows automatically
manages page file space by default, unless the machine is out of disk space,
this is typically caused by manual page file configurations that are too
small.

This patch obtains the current page file size, the amount of free page file
space, and also determines whether the page file is automatically or manually
managed.

Fixes #9090

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-08-25 10:31:36 -06:00
Aaron Klotz 5fb1695bcb util/osdiag, util/osdiag/internal/wsc: add code to probe the Windows Security Center for installed software
The Windows Security Center is a component that manages the registration of
security products on a Windows system. Only products that have obtained a
special cert from Microsoft may register themselves using the WSC API.
Practically speaking, most vendors do in fact sign up for the program as it
enhances their legitimacy.

From our perspective, this is useful because it gives us a high-signal
source of information to query for the security products installed on the
system. I've tied this query into the osdiag package and is run during
bugreports.

It uses COM bindings that were automatically generated by my prototype
metadata processor, however that program still has a few bugs, so I had
to make a few manual tweaks. I dropped those binding into an internal
package because (for the moment, at least) they are effectively
purpose-built for the osdiag use case.

We also update the wingoes dependency to pick up BSTR.

Fixes #10646

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-08-24 11:51:18 -06:00
Aaron Klotz ea693eacb6 util/winutil: add RegisterForRestart, allowing programs to indicate their preferences to the Windows restart manager
In order for the installer to restart the GUI correctly post-upgrade, we
need the GUI to be able to register its restart preferences.

This PR adds API support for doing so. I'm adding it to OSS so that it
is available should we need to do any such registrations on OSS binaries
in the future.

Updates https://github.com/tailscale/corp/issues/13998

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-08-22 15:06:48 -06:00
Aaron Klotz c17a817769 util/osdiag: add logging for winsock layered service providers to Windows bugreports
The Layered Service Provider (LSP) is a deprecated (but still supported)
mechanism for inserting user-mode DLLs into a filter chain between the
Winsock API surface (ie, ws2_32.dll) and the internal user-mode interface
to the networking stack.

While their use is becoming more rare due to the aforementioned deprecation,
it is still possible for third-party software to install their DLLs into
this filter chain and interfere with Winsock API calls. Knowing whether
this is happening is useful for troubleshooting.

Fixes https://github.com/tailscale/tailscale/issues/8142

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-08-14 15:03:54 -06:00
Aaron Klotz b07347640c util/winutil/authenticode: add missing docs for CertSubjectError
A #cleanup PR.

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-08-14 11:07:12 -06:00
Aaron Klotz 3d2e35c053 util/winutil/authenticode: fix an inaccurate doc comment
A #cleanup PR

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-08-09 15:33:49 -06:00
Aaron Klotz 37925b3e7a go.mod, cmd/tailscaled, ipn/localapi, util/osdiag, util/winutil, util/winutil/authenticode: add Windows module list to OS-specific logs that are written upon bugreport
* We update wingoes to pick up new version information functionality
  (See pe/version.go in the https://github.com/dblohm7/wingoes repo);
* We move the existing LogSupportInfo code (including necessary syscall
  stubs) out of util/winutil into a new package, util/osdiag, and implement
  the public LogSupportInfo function may be implemented for other platforms
  as needed;
* We add a new reason argument to LogSupportInfo and wire that into
  localapi's bugreport implementation;
* We add module information to the Windows implementation of LogSupportInfo
  when reason indicates a bugreport. We enumerate all loaded modules in our
  process, and for each one we gather debug, authenticode signature, and
  version information.

Fixes #7802

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-08-03 11:33:14 -06:00
Aaron Klotz 7adf15f90e cmd/tailscale/cli, util/winutil/authenticode: flesh out authenticode support
Previously, tailscale upgrade was doing the bare minimum for checking
authenticode signatures via `WinVerifyTrustEx`. This is fine, but we can do
better:

* WinVerifyTrustEx verifies that the binary's signature is valid, but it doesn't
  determine *whose* signature is valid; tailscale upgrade should also ensure that
  the binary is actually signed *by us*.
* I added the ability to check the signatures of MSI files.
* In future PRs I will be adding diagnostic logging that lists details about
  every module (ie, DLL) loaded into our process. As part of that metadata, I
  want to be able to extract information about who signed the binaries.

This code is modelled on some C++ I wrote for Firefox back in the day. See
https://searchfox.org/mozilla-central/rev/27e4816536c891d85d63695025f2549fd7976392/toolkit/xre/dllservices/mozglue/Authenticode.cpp
for reference.

Fixes #8284

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-08-01 14:27:30 -06:00
Aaron Klotz fd8c8a3700 client/tailscale: add API for verifying network lock signing deeplink
Fixes #8539

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-07-06 09:59:24 -07:00
Aaron Klotz 2aa8299c37 cmd/tailscaled, util/winutil: log our registry keys during tailscaled startup
In order to improve our ability to understand the state of policies and
registry settings when troubleshooting, we enumerate all values in all subkeys.
x/sys/windows does not already offer this, so we need to call RegEnumValue
directly.

For now we're just logging this during startup, however in a future PR I plan to
also trigger this code during a bugreport. I also want to log more than just
registry.

Fixes #8141

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-06-01 13:39:17 -06:00
Aaron Klotz 90fd04cbde ipn/ipnlocal, util/winutil/policy: modify Windows profile migration to load legacy prefs from within tailscaled
I realized that a lot of the problems that we're seeing around migration and
LocalBackend state can be avoided if we drive Windows pref migration entirely
from within tailscaled. By doing it this way, tailscaled can automatically
perform the migration as soon as the connection with the client frontend is
established.

Since tailscaled is already running as LocalSystem, it already has access to
the user's local AppData directory. The profile manager already knows which
user is connected, so we simply need to resolve the user's prefs file and read
it from there.

Of course, to properly migrate this information we need to also check system
policies. I moved a bunch of policy resolution code out of the GUI and into
a new package in util/winutil/policy.

Updates #7626

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-04-03 14:41:46 -07:00
Aaron Klotz 9687f3700d net/dns: deal with Windows wsl.exe hangs
Despite the fact that WSL configuration is still disabled by default, we
continue to log the machine's list of WSL distros as a diagnostic measure.

Unfortunately I have seen the "wsl.exe -l" command hang indefinitely. This patch
adds a (more than reasonable) 10s timeout to ensure that tailscaled does not get
stuck while executing this operation.

I also modified the Windows implementation of NewOSConfigurator to do the
logging asynchronously, since that information is not required in order to
continue starting up.

Fixes #7476

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-03-06 16:08:13 -07:00
Aaron Klotz f18beaa1e4 cmd/mkmanifest, cmd/tailscale, cmd/tailscaled: remove Windows arm32 resources from OSS
Given recent changes in corp, I originally thought we could remove all of the
syso files, but then I realized that we still need them so that binaries built
purely from OSS (without going through corp) will still receive a manifest.

We can remove the arm32 one though, since we don't support 32-bit ARM on Windows.

Updates https://github.com/tailscale/corp/issues/9576

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-03-01 15:45:12 -07:00
Aaron Klotz 4a869048bf net/netstat: add nil checks to Windows OSMetadata implementation
The API documentation does claim to output empty strings under certain
conditions, but we're sometimes seeing nil pointers in the wild, not empty
strings.

Fixes https://github.com/tailscale/corp/issues/8878

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2023-01-27 09:41:48 -07:00
Aaron Klotz 296f53524c netstat, portlist: update Windows implementation to disambiguate svchost processes
We change our invocations of GetExtendedTcpTable to request additional
information about the "module" responsible for the port. In addition to pid,
this output also includes sufficient metadata to enable Windows to resolve
process names and disambiguate svchost processes.

We store the OS-specific output in an OSMetadata field in netstat.Entry, which
portlist may then use as necessary to actually resolve the process/module name.

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-12-19 15:38:49 -06:00
Aaron Klotz 3c452b9880 util/winutil: fix erroneous condition in implementation of getRegIntegerInternal
We only want to log when err != registry.ErrNotExist. The condition was backward.

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-12-19 15:12:53 -06:00
Aaron Klotz 53e2010b8a cmd/tailscaled: change Windows implementation to shut down subprocess via closing its stdin
We've been doing a hard kill of the subprocess, which is only safe as long as
both the cli and gui are not running and the subprocess has had the opportunity
to clean up DNS settings etc. If unattended mode is turned on, this is definitely
unsafe.

I changed babysitProc to close the subprocess's stdin to make it shut down, and
then I plumbed a cancel function into the stdin reader on the subprocess side.

Fixes https://github.com/tailscale/corp/issues/5621

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-12-12 12:02:26 -06:00
Aaron Klotz 98f21354c6 cmd/tailscaled: add a special command to tailscaled's Windows service for removing WinTun
WinTun is installed lazily by tailscaled while it is running as LocalSystem.
Based upon what we're seeing in bug reports and support requests, removing
WinTun as a lesser user may fail under certain Windows versions, even when that
user is an Administrator.

By adding a user-defined command code to tailscaled, we can ask the service to
do the removal on our behalf while it is still running as LocalSystem.

* The uninstall code is basically the same as it is in corp;
* The command code will be sent as a service control request and is protected by
  the SERVICE_USER_DEFINED_CONTROL access right, which requires Administrator.

I'll be adding follow-up patches in corp to engage this functionality.

Updates https://github.com/tailscale/tailscale/issues/6433

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-12-07 12:12:02 -06:00
Aaron Klotz 659e7837c6 health, ipn/ipnlocal: when -no-logs-no-support is enabled, deny access to tailnets that have network logging enabled
We want users to have the freedom to start tailscaled with `-no-logs-no-support`,
but that is obviously in direct conflict with tailnets that have network logging
enabled.

When we detect that condition, we record the issue in health, notify the client,
set WantRunning=false, and bail.

We clear the item in health when a profile switch occurs, since it is a
per-tailnet condition that should not propagate across profiles.

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-11-29 11:42:20 -06:00
Aaron Klotz 6e33d2da2b ipn/ipnauth, util/winutil: add temporary LookupPseudoUser workaround to address os/user.LookupId errors on Windows
I added util/winutil/LookupPseudoUser, which essentially consists of the bits
that I am in the process of adding to Go's standard library.

We check the provided SID for "S-1-5-x" where 17 <= x <= 20 (which are the
known pseudo-users) and then manually populate a os/user.User struct with
the correct information.

Fixes https://github.com/tailscale/tailscale/issues/869
Fixes https://github.com/tailscale/tailscale/issues/2894

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-11-28 15:53:34 -06:00
Aaron Klotz 033bd94d4c cmd/tailscaled, wgengine/router: use wingoes/com for COM initialization instead of go-ole
This patch removes the crappy, half-backed COM initialization used by `go-ole`
and replaces that with the `StartRuntime` function from `wingoes`, a library I
have started which, among other things, initializes COM properly.

In particular, we should always be initializing COM to use the multithreaded
apartment. Every single OS thread in the process becomes implicitly initialized
as part of the MTA, so we do not need to concern ourselves as to whether or not
any particular OS thread has initialized COM. Furthermore, we no longer need to
lock the OS thread when calling methods on COM interfaces.

Single-threaded apartments are designed solely for working with Win32 threads
that have a message pump; any other use of the STA is invalid.

Fixes https://github.com/tailscale/tailscale/issues/3137

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-11-24 14:52:23 -06:00
Aaron Klotz 41e1d336cc net/dns: change windows DNS manager to use pointer receiver
This is safer given that we need to close the NRPT database.

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-11-21 15:46:51 -06:00
Aaron Klotz 73b8968404 ipn/ipnlocal: ensure Persist information is saved to server mode start state
Numerous issues have been filed concerning an inability to install and run
Tailscale headlessly in unattended mode, particularly after rebooting. The
server mode `Prefs` stored in `server-state.conf` were not being updated with
`Persist` state once the node had been succesfully logged in.

Users have been working around this by finagling with the GUI to make it force
a state rewrite. This patch makes that unnecessary by ensuring the required
server mode state is updated when prefs are updated by the control client.

Fixes https://github.com/tailscale/tailscale/issues/3186

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-11-10 10:43:40 -06:00
Aaron Klotz a44687e71f wgengine/winnet: invoke some COM methods directly instead of through IDispatch.
Intermittently in the wild we are seeing failures when calling
`INetworkConnection::GetNetwork`. It is unclear what the root cause is, but what
is clear is that the error is happening inside the object's `IDispatch` invoker
(as opposed to the method implementation itself).

This patch replaces our wrapper for `INetworkConnection::GetNetwork` with an
alternate implementation that directly invokes the method, instead of using
`IDispatch`. I also replaced the implementations of `INetwork::SetCategory` and
`INetwork::GetCategory` while I was there.

This patch is speculative and tightly-scoped so that we could possibly add it
to a dot-release if necessary.

Updates https://github.com/tailscale/tailscale/issues/4134
Updates https://github.com/tailscale/tailscale/issues/6037

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-10-27 14:05:31 -05:00
Aaron Klotz 44f13d32d7 cmd/tailscaled, util/winutil: log Windows service diagnostics when the wintun device fails to install
I added new functions to winutil to obtain the state of a service and all
its depedencies, serialize them to JSON, and write them to a Logf.

When tstun.New returns a wrapped ERROR_DEVICE_NOT_AVAILABLE, we know that wintun
installation failed. We then log the service graph rooted at "NetSetupSvc".
We are interested in that specific service because network devices will not
install if that service is not running.

Updates https://github.com/tailscale/tailscale/issues/5531

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-09-28 16:09:10 -06:00
Aaron Klotz acc7baac6d tailcfg, util/deephash: add DataPlaneAuditLogID to Node and DomainDataPlaneAuditLogID to MapResponse
We're adding two log IDs to facilitate data-plane audit logging: a node-specific
log ID, and a domain-specific log ID.

Updated util/deephash/deephash_test.go with revised expectations for tailcfg.Node.

Updates https://github.com/tailscale/corp/issues/6991

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-09-22 17:18:28 -06:00
Aaron Klotz b997304bf6 tailcfg: add CapabilityDataPlaneAuditLogs.
We're going to want to enable audit logging on a per-Tailnet basis. When this
happens, we want control to inform the Tailnet's clients of this capability.

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-08-19 14:21:17 -06:00
Aaron Klotz 4dbdb19c26 net/tshttpproxy: fix incorrect type in Windows implementation, switch to mkwinsyscall, fix memory leak
The definition of winHTTPProxyInfo was using the wrong type (uint16 vs uint32)
for its first field. I fixed that type.

Furthermore, any UTF16 strings returned in that structure must be explicitly
freed. I added code to do this.

Finally, since this is the second time I've seen type safety errors in this code,
I switched the native API calls over to use wrappers generated by mkwinsyscall.
I know that would not have helped prevent the previous two problems, but every
bit helps IMHO.

Updates https://github.com/tailscale/tailscale/issues/4811

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-07-27 16:33:57 -06:00
Aaron Klotz 446d03e108 scripts: update check_license_headers.sh to skip zsyscall_windows.go
Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-07-27 16:19:39 -06:00
Aaron Klotz 1cae618b03 net/dns: add Windows group policy notifications to the NRPT rule manager
As discussed in previous PRs, we can register for notifications when group
policies are updated and act accordingly.

This patch changes nrptRuleDatabase to receive notifications that group policy
has changed and automatically move our NRPT rules between the local and
group policy subkeys as needed.

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-07-22 14:24:39 -06:00
Aaron Klotz 4baf34cf25 net/dns: set appropriate Windows registry values to prevent it from sending DNS changes concerning our interface to AD domain controllers.
We do this unconditionally inside SetDNS such that the values are always set
before we make any other changes to DNS configurations.

It should not be harmful for the settings to remain even when other DNS
settings are cleared out (since they only affect our network interface).

See https://docs.microsoft.com/en-us/troubleshoot/windows-server/networking/configure-dns-dynamic-updates-windows-server-2003 for details about the registry value.

Fixes https://github.com/tailscale/tailscale/issues/4829

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-06-24 11:41:33 -06:00
Aaron Klotz 8cdfd12977 net/dns: update Windows split DNS settings to work alongside other NRPT entries set by group policy.
When there are group policy entries for the NRPT that do not belong to Tailscale,
we recognize that we need to add ourselves to group policy and use that registry
key instead of the local one. We also refresh the group policy settings as
necessary to ensure that our changes take effect immediately.

Fixes https://github.com/tailscale/tailscale/issues/4607

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-06-23 15:42:22 -06:00
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>
2022-05-27 14:56:09 -06:00
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>
2022-05-26 12:13:36 -06:00
Aaron KlotzandBrad Fitzpatrick d915e0054c cmd/tailscaled: change Windows service shutdown and add optional event logging
Once a stop request is received and the service updates its status to `svc.StopPending`,
it should continue running *until the shutdown sequence is complete*, and then
return out of `(*ipnService).Execute`, which automatically sends a `svc.Stopped`
notification to Windows.

To make this happen, I changed the loop so that it runs until `doneCh` is
closed, and then returns. I also removed a spurious `svc.StopPending` notification
that the Windows Service Control Manager might be interpreting as a request for
more time to shut down.

Finally, I added some optional logging that sends a record of service notifications
to the Windows event log, allowing us to more easily correlate with any Service
Control Manager errors that are sent to the same log.

Change-Id: I5b596122e5e89c4c655fe747a612a52cb4e8f1e0
Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-04-29 15:13:11 -07:00
Aaron Klotz 6e91f872af net/tshttpproxy: ensure we pass the correct flags to WinHttpOpen on Win7 and Win8.0
The best flag to use on Win7 and Win8.0 is deprecated in Win8.1, so we resolve
the flag depending on OS version info.

Fixes https://github.com/tailscale/tailscale/issues/4201

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-03-18 11:05:02 -06:00
Aaron Klotz f8a4df66de cmd/tailscale/cli, ipn: move exit node IP parsing and validation from cli into prefs.
We need to be able to provide the ability for the GUI clients to resolve and set
the exit node IP from an untrusted string, thus enabling the ability to specify
that information via enterprise policy.

This patch moves the relevant code out of the handler for `tailscale up`,
into a method on `Prefs` that may then be called by GUI clients.

We also update tests accordingly.

Updates https://github.com/tailscale/corp/issues/4239

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-03-10 10:51:05 -07:00
Aaron Klotz e31d68d64e hostinfo: use the sentinel value set by the MSI installer to detect MSI package type
The MSI installer sets a special sentinel value that we can use to detect it.

I also removed the code that bails out when the installation path is not
`Program Files`, as both the NSIS and MSI installers permit the user to install
to a different path.

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2022-02-22 12:48:20 -07:00
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>
2022-02-10 15:22:55 -07:00
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>
2022-02-09 14:58:51 -07:00
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>
2022-02-02 15:01:28 -07:00
Aaron Klotz f93cf6fa03 net/dns: fix checking for wrapped error when attempting to read wsl.conf for Windows WSL2
Fixes https://github.com/tailscale/tailscale/issues/3437

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2021-11-30 15:36:39 -07:00
Aaron Klotz 7d8feb2784 hostinfo: change Windows implementation to directly query version information using API and registry
We replace the cmd.exe invocation with RtlGetNtVersionNumbers for the first
three fields. On Windows 10+, we query for the fourth field which is available
via the registry.

The fourth field is not really documented anywhere; Firefox has been querying
it successfully since Windows 10 was released, so we can be pretty confident in
its longevity at this point.

Fixes https://github.com/tailscale/tailscale/issues/1478

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2021-11-22 12:26:42 -07:00
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>
2021-10-18 15:48:42 -06:00
Aaron Klotz 6425f497b1 ipn/ipnserver paths: add paths.LegacyStateFilePath
Moving this information into a centralized place so that it is accessible to
code in subsequent commits.

Updates #3011

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2021-10-18 15:48:42 -06:00
Aaron Klotz 1991a1ac6a net/tstun: update tun_windows for wintun 0.14 API revisions, update wireguard-go dependency to 82d2aa87aa623cb5143a41c3345da4fb875ad85d
Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2021-10-12 16:07:46 -06:00
Aaron Klotz df7899759d cmd/tailscaled: set the correct flag for receiving Windows session change events
This feature wasn't working until I realized that we also need to opt into
the events. MSDN wasn't so generous as to make this easy to deduce.

Updates #2956

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2021-10-06 10:23:55 -06:00
Aaron Klotz e016eaf410 cmd/tailscaled: conditionally flush Windows DNS cache on SessionChange
For the service, all we need to do is handle the `svc.SessionChange` command.
Upon receipt of a `windows.WTS_SESSION_UNLOCK` event, we fire off a goroutine to flush the DNS cache.
(Windows expects responses to service requests to be quick, so we don't want to do that synchronously.)

This is gated on an integral registry value named `FlushDNSOnSessionUnlock`,
whose value we obtain during service initialization.

(See [this link](https://docs.microsoft.com/en-us/windows/win32/api/winsvc/nc-winsvc-lphandler_function_ex) for information re: handling `SERVICE_CONTROL_SESSIONCHANGE`.)

Fixes #2956

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2021-09-29 09:43:22 -06:00
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>
2021-09-29 09:43:22 -06:00
Aaron Klotz 21e9f98fc1 ipn, paths: unconditionally attempt to set state dir perms, but only if the state dir is ours
We unconditionally set appropriate perms on the statefile dir.

We look at the basename of the statefile dir, and if it is "tailscale", then
we set perms as appropriate.

Fixes #2925
Updates #2856

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2021-09-24 15:53:58 -06:00
Aaron KlotzandGitHub f0aa7f70a4 Merge pull request #2893 from tailscale/aaron/programdata-perms-2
ipn, paths: ensure that the state directory for Windows has the corre…
2021-09-22 14:58:16 -06:00
Aaron Klotz 9ebb5d4205 ipn, paths: ensure that the state directory for Windows has the correct perms
ProgramData has a permissive ACL. For us to safely store machine-wide
state information, we must set a more restrictive ACL on our state directory.
We set the ACL so that only talescaled's user (ie, LocalSystem) and the
Administrators group may access our directory.

We must include Administrators to ensure that logs continue to be easily
accessible; omitting that group would force users to use special tools to
log in interactively as LocalSystem, which is not ideal.

(Note that the ACL we apply matches the ACL that was used for LocalSystem's
AppData\Local).

There are two cases where we need to reset perms: One is during migration
from the old location to the new. The second case is for clean installations
where we are creating the file store for the first time.

Updates #2856

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2021-09-22 14:50:00 -06:00