implemented pledge and unveil on openbsd

vendor/git.giftfish.de/ston1th/godrop/v2/.gitignore

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+port80
+port80fg
+port80and443

vendor/git.giftfish.de/ston1th/godrop/v2/LICENSE

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+Copyright (C) 2022 Marius Schellenberger
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+    * 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.
+    * The names of the authors and/or contributors may not 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 ston1th 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/git.giftfish.de/ston1th/godrop/v2/README.md

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+# godrop - drop privileges
+
+Godrop is a simple library to drop privileges on Linux and OpenBSD.
+
+See the examples directory on how to use the `Drop` and `MultiDrop` functions.

vendor/git.giftfish.de/ston1th/godrop/v2/godrop.go

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+// Copyright (C) 2022 Marius Schellenberger
+
+//go:build go1.11
+// +build go1.11
+
+// Package godrop provides a simple library to drop privileges on Linux and OpenBSD.
+package godrop
+
+import (
+	"errors"
+	"fmt"
+	"net"
+	"os"
+	"os/exec"
+	"os/signal"
+	"syscall"
+)
+
+// Config represents the drop config
+type Config struct {
+	// User is the user to drop privileges to.
+	User string
+	// Group is the group to drop privileges to.
+	Group string
+	// Chroot is the directory to chroot into. Leave this emptry for no chroot.
+	// When compiling without cgo, make sure the chroot directory contains the /etc/passwd and /etc/group files.
+	Chroot string
+	// Set to true, to run the process in the foreground.
+	Foreground bool
+}
+
+// Drop will spawn a new process and hand over the listening socket file descriptor
+func Drop(c Config, f func() (net.Listener, error)) error {
+	return MultiDrop(c, func() ([]net.Listener, error) {
+		l, err := f()
+		return []net.Listener{l}, err
+	})
+}
+
+// MultiDrop will spawn a new process and hand over the all listening sockets
+func MultiDrop(c Config, f func() ([]net.Listener, error)) error {
+	uid, err := userID(c.User)
+	if err != nil {
+		return errors.New("godrop: " + err.Error())
+	}
+	if uid == 0 {
+		return fmt.Errorf("godrop: you can't drop privileges to uid 0 (%s)", c.User)
+	}
+	gid, err := groupID(c.Group)
+	if err != nil {
+		return errors.New("godrop: " + err.Error())
+	}
+	switch os.Getuid() {
+	case 0:
+		cmd := exec.Command(os.Args[0], os.Args[1:]...)
+		ln, err := f()
+		if err != nil {
+			return errors.New("godrop: " + err.Error())
+		}
+		for i, v := range ln {
+			var f *os.File
+			switch l := v.(type) {
+			case *net.TCPListener:
+				f, err = l.File()
+				l.Close()
+			case *net.UnixListener:
+				f, err = l.File()
+				l.Close()
+			default:
+				return fmt.Errorf("godrop: index %d listener is not type of either *net.TCPListener or *net.UnixListener", i)
+			}
+			if err != nil {
+				return fmt.Errorf("godrop: index %d %s", i, err)
+			}
+			cmd.ExtraFiles = append(cmd.ExtraFiles, f)
+		}
+
+		cmd.SysProcAttr = &syscall.SysProcAttr{
+			Chroot: c.Chroot,
+			Credential: &syscall.Credential{
+				Uid: uint32(uid),
+				Gid: uint32(gid),
+			},
+			Setsid: true,
+		}
+
+		if c.Foreground {
+			cmd.Stdin = os.Stdin
+			cmd.Stdout = os.Stdout
+			cmd.Stderr = os.Stderr
+		}
+
+		if err := cmd.Start(); err != nil {
+			return errors.New("godrop: " + err.Error())
+		}
+
+		if c.Foreground {
+			go func() {
+				term := make(chan os.Signal)
+				signal.Notify(term, syscall.SIGHUP, syscall.SIGINT, syscall.SIGTERM, syscall.SIGQUIT)
+				sigs := make(chan os.Signal)
+				signal.Notify(sigs, syscall.SIGSTOP, syscall.SIGCONT, syscall.SIGUSR1, syscall.SIGUSR2)
+				for {
+					select {
+					case sig := <-term:
+						cmd.Process.Signal(sig)
+						return
+					case sig := <-sigs:
+						cmd.Process.Signal(sig)
+					}
+				}
+			}()
+			_ = cmd.Wait()
+			os.Exit(int(cmd.ProcessState.Sys().(syscall.WaitStatus)))
+		}
+		cmd.Process.Release()
+		os.Exit(0)
+	case uid:
+		return nil
+	}
+	return errors.New("godrop: dropping priviledges failed")
+}
+
+// GetListener returns the listener socket of file descriptor 3
+func GetListener() (net.Listener, error) {
+	return GetListenerFd(3)
+}
+
+// GetListenerFd returns the listener socket of the given file descriptor
+func GetListenerFd(fd int) (net.Listener, error) {
+	if fd < 3 {
+		return nil, errors.New("godrop: fd is less than 3")
+	}
+	f := os.NewFile(uintptr(fd), "")
+	defer f.Close()
+	return net.FileListener(f)
+}

vendor/git.giftfish.de/ston1th/godrop/v2/lookup.go

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+// Copyright (C) 2022 Marius Schellenberger
+
+//go:build go1.11
+// +build go1.11
+
+package godrop
+
+import (
+	"os/user"
+	"strconv"
+)
+
+func atoi(a string) (int, error) {
+	i, err := strconv.Atoi(a)
+	if err != nil {
+		return -1, err
+	}
+	return i, nil
+}
+
+func userID(username string) (int, error) {
+	u, err := user.Lookup(username)
+	if err != nil {
+		return -1, err
+	}
+	return atoi(u.Uid)
+}
+
+func groupID(name string) (int, error) {
+	g, err := user.LookupGroup(name)
+	if err != nil {
+		return -1, err
+	}
+	return atoi(g.Gid)
+}

vendor/git.giftfish.de/ston1th/godrop/v2/pledge.go

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+// Copyright (C) 2022 Marius Schellenberger
+
+//go:build !openbsd
+// +build !openbsd
+
+package godrop
+
+// Pledge is currently only supported on OpenBSD.
+func Pledge(promises, execpromises string) error { return nil }
+
+// PledgePromises is currently only supported on OpenBSD.
+func PledgePromises(promises string) error { return nil }
+
+// PledgeExecPromises is currently only supported on OpenBSD.
+func PledgeExecpromises(execpromises string) error { return nil }

vendor/git.giftfish.de/ston1th/godrop/v2/pledge_openbsd.go

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+// Copyright (C) 2022 Marius Schellenberger
+
+//go:build openbsd
+// +build openbsd
+
+package godrop
+
+import (
+	"errors"
+	"golang.org/x/sys/unix"
+)
+
+// Pledge is a wrapper for x/sys/unix Pledge.
+//
+// See https://go.googlesource.com/sys/+/master/unix/openbsd_pledge.go for usage.
+func Pledge(promises, execpromises string) (err error) {
+	err = unix.Pledge(promises, execpromises)
+	if err != nil {
+		err = errors.New("pledge: " + err.Error())
+	}
+	return
+}
+
+// PledgePromises is a wrapper for x/sys/unix PledgePromises.
+//
+// See https://go.googlesource.com/sys/+/master/unix/openbsd_pledge.go for usage.
+func PledgePromises(promises string) (err error) {
+	err = unix.PledgePromises(promises)
+	if err != nil {
+		err = errors.New("pledge: " + err.Error())
+	}
+	return
+}
+
+// PledgeExecpromises is a wrapper for x/sys/unix PledgeExecpromises.
+//
+// See https://go.googlesource.com/sys/+/master/unix/openbsd_pledge.go for usage.
+func PledgeExecpromises(execpromises string) (err error) {
+	err = unix.PledgeExecpromises(execpromises)
+	if err != nil {
+		err = errors.New("pledge: " + err.Error())
+	}
+	return
+}

vendor/git.giftfish.de/ston1th/godrop/v2/unveil.go

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+// Copyright (C) 2022 Marius Schellenberger
+
+//go:build !openbsd
+// +build !openbsd
+
+package godrop
+
+// Unveil is currently only supported on OpenBSD.
+func Unveil(path, flags string) error { return nil }
+
+// UnveilBlock is currently only supported on OpenBSD.
+func UnveilBlock() error { return nil }

vendor/git.giftfish.de/ston1th/godrop/v2/unveil_openbsd.go

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+// Copyright (C) 2022 Marius Schellenberger
+
+//go:build openbsd
+// +build openbsd
+
+package godrop
+
+import (
+	"errors"
+	"golang.org/x/sys/unix"
+)
+
+// Unveil is a wrapper for x/sys/unix Unveil.
+//
+// See https://go.googlesource.com/sys/+/master/unix/openbsd_unveil.go for usage.
+func Unveil(path, flags string) (err error) {
+	err = unix.Unveil(path, flags)
+	if err != nil {
+		err = errors.New("unveil: " + err.Error())
+	}
+	return
+}
+
+// UnveilBlock is a wrapper for x/sys/unix UnveilBlock.
+//
+// See https://go.googlesource.com/sys/+/master/unix/openbsd_unveil.go for usage.
+func UnveilBlock() (err error) {
+	err = unix.UnveilBlock()
+	if err != nil {
+		err = errors.New("unveil: " + err.Error())
+	}
+	return
+}