feat: Utilities for key generation and marshalling.

pkg/pki/key.go

@@ -0,0 +1,34 @@
+package pki
+
+import (
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	"crypto/rand"
+	"crypto/x509"
+	"encoding/pem"
+	"fmt"
+)
+
+// GenerateKey generates a secure ecdsa private key,
+// or panics if it can't.
+func GenerateKey() *ecdsa.PrivateKey {
+	key, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
+	if err != nil {
+		panic(fmt.Errorf("Generating key: %w", err))
+	}
+	return key
+}
+
+// MarshalKeyToPEM returns the bytes of a single encoded PEM block containing
+// the given private key. Panics if it can't encode the key.
+func MarshalKeyToPEM(key *ecdsa.PrivateKey) []byte {
+	der, err := x509.MarshalPKCS8PrivateKey(key)
+	if err != nil {
+		panic(fmt.Errorf("Encoding key: %w", err))
+	}
+
+	return pem.EncodeToMemory(&pem.Block{
+		Type:  PEMTypePrivateKey,
+		Bytes: der,
+	})
+}