Configure golangci-lint and fix warnings

signer/openpgpops/openpgpops.go

@@ -0,0 +1,127 @@
+package openpgpops
+
+import (
+	"bytes"
+	"crypto"
+	"errors"
+	"fmt"
+	"os"
+	"time"
+
+	log "github.com/sirupsen/logrus"
+	"golang.org/x/crypto/openpgp"
+	"golang.org/x/crypto/openpgp/armor"
+	"golang.org/x/crypto/openpgp/packet"
+)
+
+const hoursInADay = 24
+
+type OpenPGPRoot struct {
+	Name          string
+	SecretKeyRing string
+	Identifier    string
+}
+
+func (r *OpenPGPRoot) SignPublicKey(pubKey []byte, algorithm crypto.Hash, days uint16) ([]byte, error) {
+	signingKey, err := r.findSigningKey(r.Identifier)
+	if err != nil {
+		return nil, fmt.Errorf("could not find a signing key matching %s: %w", r.Identifier, err)
+	}
+
+	pubKeyRing, err := openpgp.ReadKeyRing(bytes.NewReader(pubKey))
+	if err != nil {
+		return nil, fmt.Errorf("could not read openpgpops keyring: %w", err)
+	}
+
+	output := bytes.NewBuffer([]byte{})
+
+	armorOutput, err := armor.Encode(output, "PGP PUBLIC KEY BLOCK", map[string]string{})
+	if err != nil {
+		return nil, fmt.Errorf("could not create ASCII armor wrapper for openpgpops output: %w", err)
+	}
+
+	for _, pe := range pubKeyRing {
+		log.Tracef("found %+v", pe.PrimaryKey.KeyIdString())
+
+		for _, i := range pe.Identities {
+			expiry := calculateExpiry(i, days)
+
+			if !i.SelfSignature.KeyExpired(time.Now()) {
+				sig := &packet.Signature{
+					SigType:         packet.SigTypeGenericCert,
+					PubKeyAlgo:      signingKey.PrivateKey.PubKeyAlgo,
+					Hash:            algorithm,
+					CreationTime:    time.Now(),
+					SigLifetimeSecs: expiry,
+					IssuerKeyId:     &signingKey.PrivateKey.KeyId,
+				}
+				if err := sig.SignUserId(i.Name, pe.PrimaryKey, signingKey.PrivateKey, &packet.Config{
+					DefaultHash: algorithm,
+				}); err != nil {
+					return nil, fmt.Errorf("could not sign identity %s: %w", i.Name, err)
+				}
+
+				i.Signatures = append(i.Signatures, sig)
+			}
+		}
+
+		if err = pe.Serialize(armorOutput); err != nil {
+			return nil, fmt.Errorf(
+				"could not write signed public key %s to output: %w",
+				pe.PrimaryKey.KeyIdString(),
+				err,
+			)
+		}
+	}
+
+	if err = armorOutput.Close(); err != nil {
+		return nil, fmt.Errorf("could not close output stream: %w", err)
+	}
+
+	log.Tracef("signed public key\n%s", output.String())
+
+	return output.Bytes(), nil
+}
+
+func calculateExpiry(i *openpgp.Identity, days uint16) *uint32 {
+	maxExpiry := time.Second * time.Duration(*i.SelfSignature.KeyLifetimeSecs)
+	calcExpiry := time.Hour * hoursInADay * time.Duration(days)
+
+	if calcExpiry > maxExpiry {
+		calcExpiry = maxExpiry
+	}
+
+	expirySeconds := uint32(calcExpiry.Seconds())
+
+	return &expirySeconds
+}
+
+func (r *OpenPGPRoot) findSigningKey(identifier string) (*openpgp.Entity, error) {
+	keyring, err := os.Open(r.SecretKeyRing)
+	if err != nil {
+		return nil, fmt.Errorf("could not open secret keyring: %w", err)
+	}
+
+	defer func() { _ = keyring.Close() }()
+
+	el, err := openpgp.ReadKeyRing(keyring)
+	if err != nil {
+		return nil, fmt.Errorf("could not read keyring: %w", err)
+	}
+
+	for _, e := range el {
+		log.Tracef("found %s", e.PrimaryKey.KeyIdString())
+
+		for _, i := range e.Identities {
+			if i.UserId.Email == identifier && len(e.Revocations) == 0 && !i.SelfSignature.KeyExpired(time.Now()) {
+				return e, nil
+			}
+		}
+	}
+
+	return nil, errors.New("no matching key found")
+}
+
+type OpenPGPProfile struct {
+	Name string
+}