Adding upstream version 9.0.3.

Signed-off-by: Daniel Baumann <daniel@debian.org>

1 files changed, 220 insertions, 0 deletions

diff --git a/models/asymkey/ssh_key_authorized_keys.go b/models/asymkey/ssh_key_authorized_keys.go
new file mode 100644
index 0000000..d3f9f3f
--- /dev/null
+++ b/models/asymkey/ssh_key_authorized_keys.go
@@ -0,0 +1,220 @@
+// Copyright 2021 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package asymkey
+
+import (
+	"bufio"
+	"context"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+	"sync"
+	"time"
+
+	"code.gitea.io/gitea/models/db"
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/util"
+)
+
+//  _____          __  .__                 .__                  .___
+// /  _  \  __ ___/  |_|  |__   ___________|__|_______ ____   __| _/
+// /  /_\  \|  |  \   __\  |  \ /  _ \_  __ \  \___   // __ \ / __ |
+// /    |    \  |  /|  | |   Y  (  <_> )  | \/  |/    /\  ___// /_/ |
+// \____|__  /____/ |__| |___|  /\____/|__|  |__/_____ \\___  >____ |
+//         \/                 \/                      \/    \/     \/
+// ____  __.
+// |    |/ _|____ ___.__. ______
+// |      <_/ __ <   |  |/  ___/
+// |    |  \  ___/\___  |\___ \
+// |____|__ \___  > ____/____  >
+//         \/   \/\/         \/
+//
+// This file contains functions for creating authorized_keys files
+//
+// There is a dependence on the database within RegeneratePublicKeys however most of these functions probably belong in a module
+
+const (
+	tplCommentPrefix = `# gitea public key`
+	tplPublicKey     = tplCommentPrefix + "\n" + `command=%s,no-port-forwarding,no-X11-forwarding,no-agent-forwarding,no-pty,no-user-rc,restrict %s` + "\n"
+)
+
+var sshOpLocker sync.Mutex
+
+// AuthorizedStringForKey creates the authorized keys string appropriate for the provided key
+func AuthorizedStringForKey(key *PublicKey) string {
+	sb := &strings.Builder{}
+	_ = setting.SSH.AuthorizedKeysCommandTemplateTemplate.Execute(sb, map[string]any{
+		"AppPath":     util.ShellEscape(setting.AppPath),
+		"AppWorkPath": util.ShellEscape(setting.AppWorkPath),
+		"CustomConf":  util.ShellEscape(setting.CustomConf),
+		"CustomPath":  util.ShellEscape(setting.CustomPath),
+		"Key":         key,
+	})
+
+	return fmt.Sprintf(tplPublicKey, util.ShellEscape(sb.String()), key.Content)
+}
+
+// appendAuthorizedKeysToFile appends new SSH keys' content to authorized_keys file.
+func appendAuthorizedKeysToFile(keys ...*PublicKey) error {
+	// Don't need to rewrite this file if builtin SSH server is enabled.
+	if setting.SSH.StartBuiltinServer || !setting.SSH.CreateAuthorizedKeysFile {
+		return nil
+	}
+
+	sshOpLocker.Lock()
+	defer sshOpLocker.Unlock()
+
+	if setting.SSH.RootPath != "" {
+		// First of ensure that the RootPath is present, and if not make it with 0700 permissions
+		// This of course doesn't guarantee that this is the right directory for authorized_keys
+		// but at least if it's supposed to be this directory and it doesn't exist and we're the
+		// right user it will at least be created properly.
+		err := os.MkdirAll(setting.SSH.RootPath, 0o700)
+		if err != nil {
+			log.Error("Unable to MkdirAll(%s): %v", setting.SSH.RootPath, err)
+			return err
+		}
+	}
+
+	fPath := filepath.Join(setting.SSH.RootPath, "authorized_keys")
+	f, err := os.OpenFile(fPath, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0o600)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	// Note: chmod command does not support in Windows.
+	if !setting.IsWindows {
+		fi, err := f.Stat()
+		if err != nil {
+			return err
+		}
+
+		// .ssh directory should have mode 700, and authorized_keys file should have mode 600.
+		if fi.Mode().Perm() > 0o600 {
+			log.Error("authorized_keys file has unusual permission flags: %s - setting to -rw-------", fi.Mode().Perm().String())
+			if err = f.Chmod(0o600); err != nil {
+				return err
+			}
+		}
+	}
+
+	for _, key := range keys {
+		if key.Type == KeyTypePrincipal {
+			continue
+		}
+		if _, err = f.WriteString(key.AuthorizedString()); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// RewriteAllPublicKeys removes any authorized key and rewrite all keys from database again.
+// Note: db.GetEngine(ctx).Iterate does not get latest data after insert/delete, so we have to call this function
+// outside any session scope independently.
+func RewriteAllPublicKeys(ctx context.Context) error {
+	// Don't rewrite key if internal server
+	if setting.SSH.StartBuiltinServer || !setting.SSH.CreateAuthorizedKeysFile {
+		return nil
+	}
+
+	sshOpLocker.Lock()
+	defer sshOpLocker.Unlock()
+
+	if setting.SSH.RootPath != "" {
+		// First of ensure that the RootPath is present, and if not make it with 0700 permissions
+		// This of course doesn't guarantee that this is the right directory for authorized_keys
+		// but at least if it's supposed to be this directory and it doesn't exist and we're the
+		// right user it will at least be created properly.
+		err := os.MkdirAll(setting.SSH.RootPath, 0o700)
+		if err != nil {
+			log.Error("Unable to MkdirAll(%s): %v", setting.SSH.RootPath, err)
+			return err
+		}
+	}
+
+	fPath := filepath.Join(setting.SSH.RootPath, "authorized_keys")
+	tmpPath := fPath + ".tmp"
+	t, err := os.OpenFile(tmpPath, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0o600)
+	if err != nil {
+		return err
+	}
+	defer func() {
+		t.Close()
+		if err := util.Remove(tmpPath); err != nil {
+			log.Warn("Unable to remove temporary authorized keys file: %s: Error: %v", tmpPath, err)
+		}
+	}()
+
+	if setting.SSH.AuthorizedKeysBackup {
+		isExist, err := util.IsExist(fPath)
+		if err != nil {
+			log.Error("Unable to check if %s exists. Error: %v", fPath, err)
+			return err
+		}
+		if isExist {
+			bakPath := fmt.Sprintf("%s_%d.gitea_bak", fPath, time.Now().Unix())
+			if err = util.CopyFile(fPath, bakPath); err != nil {
+				return err
+			}
+		}
+	}
+
+	if err := RegeneratePublicKeys(ctx, t); err != nil {
+		return err
+	}
+
+	if err := t.Sync(); err != nil {
+		return err
+	}
+	if err := t.Close(); err != nil {
+		return err
+	}
+	return util.Rename(tmpPath, fPath)
+}
+
+// RegeneratePublicKeys regenerates the authorized_keys file
+func RegeneratePublicKeys(ctx context.Context, t io.StringWriter) error {
+	if err := db.GetEngine(ctx).Where("type != ?", KeyTypePrincipal).Iterate(new(PublicKey), func(idx int, bean any) (err error) {
+		_, err = t.WriteString((bean.(*PublicKey)).AuthorizedString())
+		return err
+	}); err != nil {
+		return err
+	}
+
+	fPath := filepath.Join(setting.SSH.RootPath, "authorized_keys")
+	isExist, err := util.IsExist(fPath)
+	if err != nil {
+		log.Error("Unable to check if %s exists. Error: %v", fPath, err)
+		return err
+	}
+	if isExist {
+		f, err := os.Open(fPath)
+		if err != nil {
+			return err
+		}
+		defer f.Close()
+
+		scanner := bufio.NewScanner(f)
+		for scanner.Scan() {
+			line := scanner.Text()
+			if strings.HasPrefix(line, tplCommentPrefix) {
+				scanner.Scan()
+				continue
+			}
+			_, err = t.WriteString(line + "\n")
+			if err != nil {
+				return err
+			}
+		}
+		if err = scanner.Err(); err != nil {
+			return fmt.Errorf("RegeneratePublicKeys scan: %w", err)
+		}
+	}
+	return nil
+}