1 files changed, 55 insertions, 0 deletions
diff --git a/modules/ssh/init.go b/modules/ssh/init.go
new file mode 100644
index 00000000..21d4f899
--- /dev/null
+++ b/modules/ssh/init.go
@@ -0,0 +1,55 @@
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package ssh
+
+import (
+	"fmt"
+	"net"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/setting"
+)
+
+func Init() error {
+	if setting.SSH.Disabled {
+		builtinUnused()
+		return nil
+	}
+
+	if setting.SSH.StartBuiltinServer {
+		Listen(setting.SSH.ListenHost, setting.SSH.ListenPort, setting.SSH.ServerCiphers, setting.SSH.ServerKeyExchanges, setting.SSH.ServerMACs)
+		log.Info("SSH server started on %s. Cipher list (%v), key exchange algorithms (%v), MACs (%v)",
+			net.JoinHostPort(setting.SSH.ListenHost, strconv.Itoa(setting.SSH.ListenPort)),
+			setting.SSH.ServerCiphers, setting.SSH.ServerKeyExchanges, setting.SSH.ServerMACs,
+		)
+		return nil
+	}
+
+	builtinUnused()
+
+	// FIXME: why 0o644 for a directory .....
+	if err := os.MkdirAll(setting.SSH.KeyTestPath, 0o644); err != nil {
+		return fmt.Errorf("failed to create directory %q for ssh key test: %w", setting.SSH.KeyTestPath, err)
+	}
+
+	if len(setting.SSH.TrustedUserCAKeys) > 0 && setting.SSH.AuthorizedPrincipalsEnabled {
+		caKeysFileName := setting.SSH.TrustedUserCAKeysFile
+		caKeysFileDir := filepath.Dir(caKeysFileName)
+
+		err := os.MkdirAll(caKeysFileDir, 0o700) // SSH.RootPath by default (That is `~/.ssh` in most cases)
+		if err != nil {
+			return fmt.Errorf("failed to create directory %q for ssh trusted ca keys: %w", caKeysFileDir, err)
+		}
+
+		if err := os.WriteFile(caKeysFileName, []byte(strings.Join(setting.SSH.TrustedUserCAKeys, "\n")), 0o600); err != nil {
+			return fmt.Errorf("failed to write ssh trusted ca keys to %q: %w", caKeysFileName, err)
+		}
+	}
+
+	return nil
+}