1 files changed, 53 insertions, 0 deletions
diff --git a/load_private_key.go b/load_private_key.go
new file mode 100644
index 0000000..4678862
--- /dev/null
+++ b/load_private_key.go
@@ -0,0 +1,53 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/gibheer/pki"
+)
+
+func loadPrivateKey(path string) (pki.PrivateKey, error) {
+	if path == "" {
+		return nil, fmt.Errorf("no path given")
+	}
+	var err error
+	file, err := os.Open(path)
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+	info, err := file.Stat()
+	if err != nil {
+		return nil, err
+	}
+	if info.Mode().Perm().String()[4:] != "------" {
+		return nil, fmt.Errorf("private key must not be readable for group or world")
+	}
+
+	pems, err := parseFile(file)
+	if err != nil {
+		return nil, err
+	}
+	if len(pems) > 1 {
+		return nil, fmt.Errorf("more than one object in file")
+	}
+
+	var pk pki.PrivateKey
+	for key, parts := range pems {
+		if len(parts) > 1 {
+			return nil, fmt.Errorf("more than one object found")
+		}
+		switch key {
+		case pki.PemLabelRsa:
+			pk, err = pki.LoadPrivateKeyRsa(parts[0])
+		case pki.PemLabelEd25519:
+			pk, err = pki.LoadPrivateKeyEd25519(parts[0])
+		case pki.PemLabelEcdsa:
+			pk, err = pki.LoadPrivateKeyEcdsa(parts[0])
+		default:
+			return nil, fmt.Errorf("unknown private key format %s", key)
+		}
+	}
+	return pk, err
+}