Refactor SSH configuration and key management

- Restrict to specific key exchanges / MACs / ciphers.
- Refactored GetSSHKey method to return an ssh.Signer instead of byte array.
- Added common package.

Co-authored-by: nhas <jordanatararimu@gmail.com>
This commit is contained in:
henrygd
2025-05-07 20:03:21 -04:00
parent c0a6153a43
commit 63af81666b
4 changed files with 74 additions and 64 deletions

View File

@@ -10,11 +10,13 @@ import (
"beszel/site"
"crypto/ed25519"
"encoding/pem"
"fmt"
"io/fs"
"net/http"
"net/http/httputil"
"net/url"
"os"
"path"
"strings"
"github.com/pocketbase/pocketbase"
@@ -239,73 +241,47 @@ func (h *Hub) registerApiRoutes(se *core.ServeEvent) error {
return nil
}
// generates key pair if it doesn't exist and returns private key bytes
func (h *Hub) GetSSHKey() ([]byte, error) {
dataDir := h.DataDir()
// generates key pair if it doesn't exist and returns signer
func (h *Hub) GetSSHKey() (ssh.Signer, error) {
privateKeyPath := path.Join(h.DataDir(), "id_ed25519")
// check if the key pair already exists
existingKey, err := os.ReadFile(dataDir + "/id_ed25519")
existingKey, err := os.ReadFile(privateKeyPath)
if err == nil {
if pubKey, err := os.ReadFile(h.DataDir() + "/id_ed25519.pub"); err == nil {
h.pubKey = strings.TrimSuffix(string(pubKey), "\n")
private, err := ssh.ParsePrivateKey(existingKey)
if err != nil {
return nil, fmt.Errorf("failed to parse private key: %s", err)
}
// return existing private key
return existingKey, nil
pubKeyBytes := ssh.MarshalAuthorizedKey(private.PublicKey())
h.pubKey = strings.TrimSuffix(string(pubKeyBytes), "\n")
return private, nil
}
// Generate the Ed25519 key pair
pubKey, privKey, err := ed25519.GenerateKey(nil)
if err != nil {
// h.Logger().Error("Error generating key pair:", "err", err.Error())
return nil, err
}
// Get the private key in OpenSSH format
privKeyBytes, err := ssh.MarshalPrivateKey(privKey, "")
if err != nil {
// h.Logger().Error("Error marshaling private key:", "err", err.Error())
return nil, err
}
// Save the private key to a file
privateFile, err := os.Create(dataDir + "/id_ed25519")
if err != nil {
// h.Logger().Error("Error creating private key file:", "err", err.Error())
return nil, err
}
defer privateFile.Close()
if err := pem.Encode(privateFile, privKeyBytes); err != nil {
// h.Logger().Error("Error writing private key to file:", "err", err.Error())
return nil, err
}
// Generate the public key in OpenSSH format
publicKey, err := ssh.NewPublicKey(pubKey)
privKeyPem, err := ssh.MarshalPrivateKey(privKey, "")
if err != nil {
return nil, err
}
pubKeyBytes := ssh.MarshalAuthorizedKey(publicKey)
if err := os.WriteFile(privateKeyPath, pem.EncodeToMemory(privKeyPem), 0600); err != nil {
return nil, fmt.Errorf("failed to write private key to %q: err: %w", privateKeyPath, err)
}
// These are fine to ignore the errors on, as we've literally just created a crypto.PublicKey | crypto.Signer
sshPubKey, _ := ssh.NewPublicKey(pubKey)
sshPrivate, _ := ssh.NewSignerFromSigner(privKey)
pubKeyBytes := ssh.MarshalAuthorizedKey(sshPubKey)
h.pubKey = strings.TrimSuffix(string(pubKeyBytes), "\n")
// Save the public key to a file
publicFile, err := os.Create(dataDir + "/id_ed25519.pub")
if err != nil {
return nil, err
}
defer publicFile.Close()
if _, err := publicFile.Write(pubKeyBytes); err != nil {
return nil, err
}
h.Logger().Info("ed25519 SSH key pair generated successfully.")
h.Logger().Info("Private key saved to: " + dataDir + "/id_ed25519")
h.Logger().Info("Public key saved to: " + dataDir + "/id_ed25519.pub")
h.Logger().Info("Saved to: " + privateKeyPath)
existingKey, err = os.ReadFile(dataDir + "/id_ed25519")
if err == nil {
return existingKey, nil
}
return nil, err
return sshPrivate, err
}