Update dependencies

vendor/github.com/tailscale/peercred/AUTHORS

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+Tailscale Inc

vendor/github.com/tailscale/peercred/LICENSE

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+BSD 3-Clause License
+
+Copyright (c) 2021, Tailscale Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+
+3. Neither the name of the copyright holder nor the names of its
+   contributors may be used to endorse or promote products derived from
+   this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/tailscale/peercred/README.md

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+# peercred

vendor/github.com/tailscale/peercred/peercred.go

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+// Copyright (c) 2021 AUTHORS All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package peercred maps from a net.Conn to information about the
+// other side of the connection, using various OS-specific facilities.
+package peercred
+
+import (
+	"errors"
+	"net"
+	"runtime"
+)
+
+// Creds are the peer credentials.
+type Creds struct {
+	pid int
+	uid string
+}
+
+func (c *Creds) PID() (pid int, ok bool) {
+	return c.pid, c.pid != 0
+}
+
+// UserID returns the userid (or Windows SID) that owns the other side
+// of the connection, if known. (ok is false if not known)
+// The returned string is suitable to passing to os/user.LookupId.
+func (c *Creds) UserID() (uid string, ok bool) {
+	return c.uid, c.uid != ""
+}
+
+var osGet func(net.Conn) (*Creds, error)
+
+var (
+	ErrNotImplemented      = errors.New("not implemented on " + runtime.GOOS)
+	ErrUnsupportedConnType = errors.New("unsupported connection type")
+)
+
+// Get returns the peer credentials for c.
+//
+// For unsupported system, the error is ErrNotImplemented.
+func Get(c net.Conn) (*Creds, error) {
+	if osGet == nil {
+		return nil, ErrNotImplemented
+	}
+	return osGet(c)
+}

vendor/github.com/tailscale/peercred/peercred_darwin.go

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+// Copyright (c) 2021 AUTHORS All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package peercred
+
+import (
+	"fmt"
+	"net"
+	"strconv"
+
+	"golang.org/x/sys/unix"
+)
+
+func init() {
+	osGet = getDarwin
+}
+
+func getDarwin(c net.Conn) (*Creds, error) {
+	switch c := c.(type) {
+	case *net.UnixConn:
+		return getUnix(c)
+	case *net.TCPConn:
+		// TODO: use /proc tcp info for localhost connections like Windows?
+	}
+	return nil, ErrUnsupportedConnType
+}
+
+func getUnix(c *net.UnixConn) (*Creds, error) {
+	raw, err := c.SyscallConn()
+	if err != nil {
+		return nil, fmt.Errorf("SyscallConn: %w", err)
+	}
+
+	var cred *unix.Xucred
+	var pid int
+	cerr := raw.Control(func(fd uintptr) {
+		cred, err = unix.GetsockoptXucred(int(fd),
+			unix.SOL_LOCAL,
+			unix.LOCAL_PEERCRED)
+		if err != nil {
+			err = fmt.Errorf("unix.GetsockoptXucred: %w", err)
+			return
+		}
+		pid, err = unix.GetsockoptInt(int(fd),
+			unix.SOL_LOCAL,
+			unix.LOCAL_PEERPID)
+		if err != nil {
+			err = fmt.Errorf("unix.GetsockoptInt: %w", err)
+		}
+	})
+	if cerr != nil {
+		return nil, fmt.Errorf("raw.Control: %w", cerr)
+	}
+	if err != nil {
+		return nil, err
+	}
+	return &Creds{
+		pid: pid,
+		uid: strconv.FormatUint(uint64(cred.Uid), 10),
+	}, nil
+}

vendor/github.com/tailscale/peercred/peercred_freebsd.go

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+// Copyright (c) 2021 AUTHORS All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package peercred
+
+import (
+	"fmt"
+	"net"
+	"strconv"
+
+	"golang.org/x/sys/unix"
+)
+
+func init() {
+	osGet = getFreeBSD
+}
+
+func getFreeBSD(c net.Conn) (*Creds, error) {
+	switch c := c.(type) {
+	case *net.UnixConn:
+		return getUnix(c)
+	case *net.TCPConn:
+		// TODO: use sysctl net.inet.tcp.pcblist for localhost connections like Windows?
+	}
+	return nil, ErrUnsupportedConnType
+}
+
+func getUnix(c *net.UnixConn) (*Creds, error) {
+	raw, err := c.SyscallConn()
+	if err != nil {
+		return nil, fmt.Errorf("SyscallConn: %w", err)
+	}
+
+	var cred *unix.Xucred
+	cerr := raw.Control(func(fd uintptr) {
+		cred, err = unix.GetsockoptXucred(int(fd),
+			unix.SOL_LOCAL,
+			unix.LOCAL_PEERCRED)
+		if err != nil {
+			err = fmt.Errorf("unix.GetsockoptXucred: %w", err)
+			return
+		}
+	})
+	if cerr != nil {
+		return nil, fmt.Errorf("raw.Control: %w", cerr)
+	}
+	if err != nil {
+		return nil, err
+	}
+	return &Creds{
+		pid: 0, // FreeBSD 13 adds a cr_pid field, can be used here.
+		uid: strconv.FormatUint(uint64(cred.Uid), 10),
+	}, nil
+}

vendor/github.com/tailscale/peercred/peercred_linux.go

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+// Copyright (c) 2021 AUTHORS All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package peercred
+
+import (
+	"fmt"
+	"net"
+	"strconv"
+
+	"golang.org/x/sys/unix"
+)
+
+func init() {
+	osGet = getLinux
+}
+
+func getLinux(c net.Conn) (*Creds, error) {
+	switch c := c.(type) {
+	case *net.UnixConn:
+		return getUnix(c)
+	case *net.TCPConn:
+		// TODO: use /proc tcp info for localhost connections like Windows?
+	}
+	return nil, ErrUnsupportedConnType
+}
+
+func getUnix(c *net.UnixConn) (*Creds, error) {
+	raw, err := c.SyscallConn()
+	if err != nil {
+		return nil, fmt.Errorf("SyscallConn: %w", err)
+	}
+
+	var cred *unix.Ucred
+	cerr := raw.Control(func(fd uintptr) {
+		cred, err = unix.GetsockoptUcred(int(fd),
+			unix.SOL_SOCKET,
+			unix.SO_PEERCRED)
+	})
+	if cerr != nil {
+		return nil, fmt.Errorf("raw.Control: %w", cerr)
+	}
+	if err != nil {
+		return nil, fmt.Errorf("unix.GetsockoptUcred: %w", err)
+	}
+	return &Creds{
+		pid: int(cred.Pid),
+		uid: strconv.FormatUint(uint64(cred.Uid), 10),
+	}, nil
+}