From 9f921135f7d99b2dbf38115dee8fa76212772e0e Mon Sep 17 00:00:00 2001
From: stephen mcquay <stephen@mcquay.me>
Date: Sun, 25 Feb 2018 03:11:40 -0800
Subject: [PATCH] Adds pm key create

---
 keyring/keyring.go | 106 +++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 97 insertions(+), 9 deletions(-)

diff --git a/keyring/keyring.go b/keyring/keyring.go
index 24b8634..591845b 100644
--- a/keyring/keyring.go
+++ b/keyring/keyring.go
@@ -1,7 +1,6 @@
 package keyring
 
 import (
-	"log"
 	"os"
 	"path/filepath"
 
@@ -11,18 +10,107 @@ import (
 	"mcquay.me/fs"
 )
 
+// NewKeyPair creates and adds a new OpenPGP keypair to an existing keyring.
 func NewKeyPair(root, name, email string) error {
-	pgpDir := filepath.Join(root, "var", "lib", "pm", "pgp")
-	if !fs.Exists(pgpDir) {
-		if err := os.MkdirAll(pgpDir, 0755); err != nil {
-			return errors.Wrap(err, "mk pgp dir")
-		}
+	if err := ensureDir(root); err != nil {
+		return errors.Wrap(err, "can't find or create pgp dir")
+	}
+	srn, prn := getNames(root)
+	secs, pubs, err := getELs(srn, prn)
+	if err != nil {
+		return errors.Wrap(err, "getting existing keyrings")
 	}
 
-	e, err := openpgp.NewEntity(name, "pm", email, nil)
+	fresh, err := openpgp.NewEntity(name, "pm", email, nil)
 	if err != nil {
 		errors.Wrap(err, "new entity")
 	}
-	log.Printf("%+v", e)
-	return errors.New("NYI")
+
+	pr, err := os.Create(prn)
+	if err != nil {
+		return errors.Wrap(err, "opening pubring")
+	}
+	sr, err := os.Create(srn)
+	if err != nil {
+		return errors.Wrap(err, "opening secring")
+	}
+
+	for _, e := range secs {
+		if err := e.SerializePrivate(sr, nil); err != nil {
+			return errors.Wrapf(err, "serializing old private key: %v", e.PrimaryKey.KeyIdString())
+		}
+	}
+	// order is critical here; if we don't serialize the private key of fresh
+	// first, the later steps fail.
+	if err := fresh.SerializePrivate(sr, nil); err != nil {
+		return errors.Wrapf(err, "serializing fresh private %v", fresh.PrimaryKey.KeyIdString())
+	}
+	if err := sr.Close(); err != nil {
+		return errors.Wrap(err, "closing secring")
+	}
+
+	for _, e := range pubs {
+		if err := e.Serialize(pr); err != nil {
+			return errors.Wrapf(err, "serializing %v", e.PrimaryKey.KeyIdString())
+		}
+	}
+	if err := fresh.Serialize(pr); err != nil {
+		return errors.Wrapf(err, "serializing %v", fresh.PrimaryKey.KeyIdString())
+	}
+	if err := pr.Close(); err != nil {
+		return errors.Wrap(err, "closing pubring")
+	}
+	return nil
+}
+
+func pGPDir(root string) string {
+	return filepath.Join(root, "var", "lib", "pm", "pgp")
+}
+
+func ensureDir(root string) error {
+	d := pGPDir(root)
+	if !fs.Exists(d) {
+		if err := os.MkdirAll(d, 0700); err != nil {
+			return errors.Wrap(err, "mk pgp dir")
+		}
+	}
+	return nil
+}
+
+func getNames(root string) (string, string) {
+	srn := filepath.Join(pGPDir(root), "secring.gpg")
+	prn := filepath.Join(pGPDir(root), "pubring.gpg")
+	return srn, prn
+}
+
+func getELs(secring, pubring string) (openpgp.EntityList, openpgp.EntityList, error) {
+	var sr, pr openpgp.EntityList
+	if fs.Exists(secring) {
+		f, err := os.Open(secring)
+		if err != nil {
+			return nil, nil, errors.Wrap(err, "opening secring")
+		}
+		sr, err = openpgp.ReadKeyRing(f)
+		if err != nil {
+			return nil, nil, errors.Wrap(err, "read sec key ring")
+		}
+		if err := f.Close(); err != nil {
+			return nil, nil, errors.Wrap(err, "closing keyring")
+		}
+	}
+
+	if fs.Exists(pubring) {
+		f, err := os.Open(pubring)
+		if err != nil {
+			return nil, nil, errors.Wrap(err, "opening pubring")
+		}
+		pr, err = openpgp.ReadKeyRing(f)
+		if err != nil {
+			return nil, nil, errors.Wrap(err, "read pub key ring")
+		}
+		if err := f.Close(); err != nil {
+			return nil, nil, errors.Wrap(err, "closing keyring")
+		}
+	}
+	return sr, pr, nil
 }