feat: add gpg integration

This commit adds gpg system integration. This is done through two new
packages: gpgbin, which handles the system calls and parsing; and gpg
which is mostly a copy of emersion/go-pgpmail with modifications to
interface with package gpgbin. gpg includes tests for many cases, and
by it's nature also tests package gpgbin. I separated these in case an
external dependency is ever used for the gpg sys-calls/parsing (IE we
mirror how go-pgpmail+openpgp currently are dependencies)

Two new config options are introduced:
* pgp-provider. If it is not explicitly set to "gpg", aerc will default to
it's internal pgp provider
* pgp-key-id: (Optionally) specify a key by short or long keyId

Signed-off-by: Tim Culverhouse <tim@timculverhouse.com>
Acked-by: Koni Marti <koni.marti@gmail.com>
Acked-by: Robin Jarry <robin@jarry.cc>

1 files changed, 35 insertions, 0 deletions

diff --git a/lib/crypto/gpg/gpgbin/encrypt.go b/lib/crypto/gpg/gpgbin/encrypt.go
new file mode 100644
index 00000000..4cbac37b
--- /dev/null
+++ b/lib/crypto/gpg/gpgbin/encrypt.go
@@ -0,0 +1,35 @@
+package gpgbin
+
+import (
+	"bytes"
+	"io"
+
+	"git.sr.ht/~rjarry/aerc/models"
+)
+
+// Encrypt runs gpg --encrypt [--sign] -r [recipient]. The default is to have
+// --trust-model always set
+func Encrypt(r io.Reader, to []string, from string) ([]byte, error) {
+	//TODO probably shouldn't have --trust-model always a default
+	args := []string{
+		"--armor",
+		"--trust-model", "always",
+	}
+	if from != "" {
+		args = append(args, "--sign", "--default-key", from)
+	}
+	for _, rcpt := range to {
+		args = append(args, "--recipient", rcpt)
+	}
+	args = append(args, "--encrypt", "-")
+
+	g := newGpg(r, args)
+	g.cmd.Run()
+	outRdr := bytes.NewReader(g.stdout.Bytes())
+	var md models.MessageDetails
+	parse(outRdr, &md)
+	var buf bytes.Buffer
+	io.Copy(&buf, md.Body)
+
+	return buf.Bytes(), nil
+}