refactor: yeet util/ subdirs

sshkey/ssh_key.go

@@ -0,0 +1,47 @@
+package sshkey
+
+import (
+	"crypto/ed25519"
+	"encoding/pem"
+
+	"golang.org/x/crypto/ssh"
+)
+
+// From https://gitlab.com/hetznercloud/fleeting-plugin-hetzner/-/blob/0f60204582289c243599f8ca0f5be4822789131d/internal/utils/ssh_key.go
+
+func GenerateKeyPair() ([]byte, []byte, error) {
+	pub, priv, err := ed25519.GenerateKey(nil)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	pubBytes, err := encodePublicKey(pub)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	privBytes, err := encodePrivateKey(priv)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	return pubBytes, privBytes, nil
+}
+
+func encodePublicKey(pub ed25519.PublicKey) ([]byte, error) {
+	sshPub, err := ssh.NewPublicKey(pub)
+	if err != nil {
+		return nil, err
+	}
+
+	return ssh.MarshalAuthorizedKey(sshPub), nil
+}
+
+func encodePrivateKey(priv ed25519.PrivateKey) ([]byte, error) {
+	privPem, err := ssh.MarshalPrivateKey(priv, "")
+	if err != nil {
+		return nil, err
+	}
+
+	return pem.EncodeToMemory(privPem), nil
+}

sshkey/ssh_key_test.go

@@ -0,0 +1,25 @@
+package sshkey
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestGenerateSSHKeyPair(t *testing.T) {
+	pubBytes, privBytes, err := GenerateKeyPair()
+	assert.Nil(t, err)
+
+	pub := string(pubBytes)
+	priv := string(privBytes)
+
+	if !(strings.HasPrefix(priv, "-----BEGIN OPENSSH PRIVATE KEY-----\n") &&
+		strings.HasSuffix(priv, "-----END OPENSSH PRIVATE KEY-----\n")) {
+		assert.Fail(t, "private key is invalid", priv)
+	}
+
+	if !strings.HasPrefix(pub, "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAA") {
+		assert.Fail(t, "public key is invalid", pub)
+	}
+}