Fix verification of signature for PGP/MIME messages

We fix the verification of embedded and PGM/MIME signatures
when decrypting PGP/MIME messages.

crypto/mime.go

@@ -10,6 +10,7 @@ import (
 	"github.com/ProtonMail/go-crypto/openpgp"
 	"github.com/ProtonMail/go-crypto/openpgp/packet"
 	gomime "github.com/ProtonMail/go-mime"
+	"github.com/ProtonMail/gopenpgp/v2/constants"
 	"github.com/pkg/errors"
 )
 
@@ -28,16 +29,26 @@ func (keyRing *KeyRing) DecryptMIMEMessage(
 	message *PGPMessage, verifyKey *KeyRing, callbacks MIMECallbacks, verifyTime int64,
 ) {
 	decryptedMessage, err := keyRing.Decrypt(message, verifyKey, verifyTime)
+	embeddedSigError, err := separateSigError(err)
 	if err != nil {
 		callbacks.OnError(err)
 		return
 	}
-
 	body, attachments, attachmentHeaders, err := parseMIME(string(decryptedMessage.GetBinary()), verifyKey)
+	mimeSigError, err := separateSigError(err)
 	if err != nil {
 		callbacks.OnError(err)
 		return
 	}
+	// We only consider the signature to be failed if both embedded and mime verification failed
+	if embeddedSigError != nil && mimeSigError != nil {
+		callbacks.OnError(embeddedSigError)
+		callbacks.OnError(mimeSigError)
+		callbacks.OnVerified(prioritizeSignatureErrors(embeddedSigError, mimeSigError))
+		return
+	} else if verifyKey != nil {
+		callbacks.OnVerified(constants.SIGNATURE_OK)
+	}
 	bodyContent, bodyMimeType := body.GetBody()
 	callbacks.OnBody(bodyContent, bodyMimeType)
 	for i := 0; i < len(attachments); i++ {
@@ -48,6 +59,27 @@ func (keyRing *KeyRing) DecryptMIMEMessage(
 
 // ----- INTERNAL FUNCTIONS -----
 
+func prioritizeSignatureErrors(signatureErrs ...*SignatureVerificationError) (maxError int) {
+	// select error with the highest value, if any
+	// FAILED > NO VERIFIER > NOT SIGNED > SIGNATURE OK
+	maxError = constants.SIGNATURE_OK
+	for _, err := range signatureErrs {
+		if err.Status > maxError {
+			maxError = err.Status
+		}
+	}
+	return
+}
+
+func separateSigError(err error) (*SignatureVerificationError, error) {
+	sigErr := &SignatureVerificationError{}
+	isSigError := errors.As(err, sigErr)
+	if isSigError {
+		return sigErr, nil
+	}
+	return nil, err
+}
+
 func parseMIME(
 	mimeBody string, verifierKey *KeyRing,
 ) (*gomime.BodyCollector, []string, []string, error) {
@@ -68,12 +100,12 @@ func parseMIME(
 	attachmentsCollector := gomime.NewAttachmentsCollector(bodyCollector)
 	mimeVisitor := gomime.NewMimeVisitor(attachmentsCollector)
 
-	var pgpKering openpgp.KeyRing
+	var verifierEntities openpgp.KeyRing
 	if verifierKey != nil {
-		pgpKering = verifierKey.entities
+		verifierEntities = verifierKey.entities
 	}
 
-	signatureCollector := newSignatureCollector(mimeVisitor, pgpKering, config)
+	signatureCollector := newSignatureCollector(mimeVisitor, verifierEntities, config)
 
 	err = gomime.VisitAll(bytes.NewReader(mmBodyData), h, signatureCollector)
 	if err == nil && verifierKey != nil {

crypto/mime_test.go

@@ -1,6 +1,9 @@
 package crypto
 
 import (
+	"errors"
+	"io/ioutil"
+	"path/filepath"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -79,3 +82,261 @@ func TestParse(t *testing.T) {
 	assert.Exactly(t, readTestFile("mime_decodedBodyHeaders", false), body.GetHeaders())
 	assert.Exactly(t, 2, len(atts))
 }
+
+type testMIMECallbacks struct {
+	onBody       []struct{ body, mimetype string }
+	onAttachment []struct {
+		headers string
+		data    []byte
+	}
+	onEncryptedHeaders []string
+	onVerified         []int
+	onError            []error
+}
+
+func (tc *testMIMECallbacks) OnBody(body string, mimetype string) {
+	tc.onBody = append(tc.onBody, struct {
+		body     string
+		mimetype string
+	}{body, mimetype})
+}
+
+func (tc *testMIMECallbacks) OnAttachment(headers string, data []byte) {
+	tc.onAttachment = append(tc.onAttachment, struct {
+		headers string
+		data    []byte
+	}{headers, data})
+}
+
+func (tc *testMIMECallbacks) OnEncryptedHeaders(headers string) {
+	tc.onEncryptedHeaders = append(tc.onEncryptedHeaders, headers)
+}
+
+func (tc *testMIMECallbacks) OnVerified(status int) {
+	tc.onVerified = append(tc.onVerified, status)
+}
+
+func (tc *testMIMECallbacks) OnError(err error) {
+	tc.onError = append(tc.onError, err)
+}
+
+func loadPrivateKeyRing(file string, passphrase string) (*KeyRing, error) {
+	armored, err := ioutil.ReadFile(filepath.Clean(file))
+	if err != nil {
+		return nil, err
+	}
+	key, err := NewKeyFromArmored(string(armored))
+	if err != nil {
+		return nil, err
+	}
+	unlockedKey, err := key.Unlock([]byte(passphrase))
+	if err != nil {
+		return nil, err
+	}
+	keyRing, err := NewKeyRing(unlockedKey)
+	if err != nil {
+		return nil, err
+	}
+	return keyRing, nil
+}
+
+func loadPublicKeyRing(file string) (*KeyRing, error) {
+	armored, err := ioutil.ReadFile(filepath.Clean(file))
+	if err != nil {
+		return nil, err
+	}
+	key, err := NewKeyFromArmored(string(armored))
+	if err != nil {
+		return nil, err
+	}
+	if key.IsPrivate() {
+		publicKey, err := key.GetPublicKey()
+		if err != nil {
+			return nil, err
+		}
+		key, err = NewKey(publicKey)
+		if err != nil {
+			return nil, err
+		}
+	}
+	keyRing, err := NewKeyRing(key)
+	if err != nil {
+		return nil, err
+	}
+	return keyRing, nil
+}
+
+func loadMessage(file string) (*PGPMessage, error) {
+	armored, err := ioutil.ReadFile(filepath.Clean(file))
+	if err != nil {
+		return nil, err
+	}
+	message, err := NewPGPMessageFromArmored(string(armored))
+	if err != nil {
+		return nil, err
+	}
+	return message, nil
+}
+
+func runScenario(t *testing.T, messageFile string) *testMIMECallbacks {
+	decryptionKeyRing, err := loadPrivateKeyRing("testdata/mime/decryption-key.asc", "test_passphrase")
+	if err != nil {
+		t.Errorf("Failed to load decryption key %v", err)
+	}
+	verificationKeyRing, err := loadPublicKeyRing("testdata/mime/verification-key.asc")
+	if err != nil {
+		t.Errorf("Failed to load verification key %v", err)
+	}
+	message, err := loadMessage(messageFile)
+	if err != nil {
+		t.Errorf("Failed to load message %v", err)
+	}
+	callbacks := &testMIMECallbacks{}
+	decryptionKeyRing.DecryptMIMEMessage(message, verificationKeyRing, callbacks, 0)
+	return callbacks
+}
+
+func compareStatus(expected []int, actual []int, t *testing.T) {
+	if len(actual) != len(expected) {
+		t.Errorf("Expected %v, got %v", expected, actual)
+	} else {
+		for i, actualStatus := range actual {
+			if actualStatus != expected[i] {
+				t.Errorf("Expected status %v, got %v", expected[i], actualStatus)
+			}
+		}
+	}
+}
+
+func TestMessageVerificationOkOk(t *testing.T) {
+	callbackResults := runScenario(t, "testdata/mime/scenario_00.asc")
+	if len(callbackResults.onError) != 0 {
+		for _, err := range callbackResults.onError {
+			t.Errorf("Expected no errors got %v", err)
+		}
+	}
+	expectedStatus := []int{0}
+	compareStatus(expectedStatus, callbackResults.onVerified, t)
+}
+
+func TestMessageVerificationOkNotSigned(t *testing.T) {
+	callbackResults := runScenario(t, "testdata/mime/scenario_01.asc")
+	if len(callbackResults.onError) != 0 {
+		for _, err := range callbackResults.onError {
+			t.Errorf("Expected no errors got %v", err)
+		}
+	}
+	expectedStatus := []int{0}
+	compareStatus(expectedStatus, callbackResults.onVerified, t)
+}
+
+func TestMessageVerificationOkNoVerifier(t *testing.T) {
+	callbackResults := runScenario(t, "testdata/mime/scenario_02.asc")
+	if len(callbackResults.onError) != 0 {
+		for _, err := range callbackResults.onError {
+			t.Errorf("Expected no errors got %v", err)
+		}
+	}
+	expectedStatus := []int{0}
+	compareStatus(expectedStatus, callbackResults.onVerified, t)
+}
+
+func TestMessageVerificationOkFailed(t *testing.T) {
+	callbackResults := runScenario(t, "testdata/mime/scenario_03.asc")
+	if len(callbackResults.onError) != 0 {
+		for _, err := range callbackResults.onError {
+			t.Errorf("Expected no errors got %v", err)
+		}
+	}
+	expectedStatus := []int{0}
+	compareStatus(expectedStatus, callbackResults.onVerified, t)
+}
+
+func TestMessageVerificationNotSignedOk(t *testing.T) {
+	callbackResults := runScenario(t, "testdata/mime/scenario_10.asc")
+	if len(callbackResults.onError) != 0 {
+		for _, err := range callbackResults.onError {
+			t.Errorf("Expected no errors got %v", err)
+		}
+	}
+	expectedStatus := []int{0}
+	compareStatus(expectedStatus, callbackResults.onVerified, t)
+}
+
+func checkIsSigErr(t *testing.T, err error) int {
+	sigErr := &SignatureVerificationError{}
+	if errors.As(err, &sigErr) {
+		return sigErr.Status
+	}
+	t.Errorf("Expected a signature verification error, got %v", err)
+	return -1
+}
+
+func compareErrors(expected []SignatureVerificationError, actual []error, t *testing.T) {
+	if len(actual) != len(expected) {
+		t.Errorf("Expected %v, got %v", expected, actual)
+	} else {
+		for i, err := range actual {
+			actualStatus := checkIsSigErr(t, err)
+			if actualStatus != expected[i].Status {
+				t.Errorf("Expected sig error with status %v, got %v", expected[i].Status, actualStatus)
+			}
+		}
+	}
+}
+
+func TestMessageVerificationNotSignedNotSigned(t *testing.T) {
+	callbackResults := runScenario(t, "testdata/mime/scenario_11.asc")
+	var expectedErrors = []SignatureVerificationError{newSignatureNotSigned(), newSignatureNotSigned()}
+	compareErrors(expectedErrors, callbackResults.onError, t)
+	expectedStatus := []int{1}
+	compareStatus(expectedStatus, callbackResults.onVerified, t)
+}
+
+func TestMessageVerificationNotSignedNoVerifier(t *testing.T) {
+	callbackResults := runScenario(t, "testdata/mime/scenario_12.asc")
+	var expectedErrors = []SignatureVerificationError{newSignatureNotSigned(), newSignatureNoVerifier()}
+	compareErrors(expectedErrors, callbackResults.onError, t)
+	expectedStatus := []int{2}
+	compareStatus(expectedStatus, callbackResults.onVerified, t)
+}
+
+func TestMessageVerificationNotSignedFailed(t *testing.T) {
+	callbackResults := runScenario(t, "testdata/mime/scenario_13.asc")
+	var expectedErrors = []SignatureVerificationError{newSignatureNotSigned(), newSignatureFailed()}
+	compareErrors(expectedErrors, callbackResults.onError, t)
+	expectedStatus := []int{3}
+	compareStatus(expectedStatus, callbackResults.onVerified, t)
+}
+
+func TestMessageVerificationNoVerifierOk(t *testing.T) {
+	callbackResults := runScenario(t, "testdata/mime/scenario_20.asc")
+	var expectedErrors = []SignatureVerificationError{}
+	compareErrors(expectedErrors, callbackResults.onError, t)
+	expectedStatus := []int{0}
+	compareStatus(expectedStatus, callbackResults.onVerified, t)
+}
+
+func TestMessageVerificationNoVerifierNotSigned(t *testing.T) {
+	callbackResults := runScenario(t, "testdata/mime/scenario_21.asc")
+	var expectedErrors = []SignatureVerificationError{newSignatureNoVerifier(), newSignatureNotSigned()}
+	compareErrors(expectedErrors, callbackResults.onError, t)
+	expectedStatus := []int{2}
+	compareStatus(expectedStatus, callbackResults.onVerified, t)
+}
+
+func TestMessageVerificationNoVerifierNoVerifier(t *testing.T) {
+	callbackResults := runScenario(t, "testdata/mime/scenario_22.asc")
+	var expectedErrors = []SignatureVerificationError{newSignatureNoVerifier(), newSignatureNoVerifier()}
+	compareErrors(expectedErrors, callbackResults.onError, t)
+	expectedStatus := []int{2}
+	compareStatus(expectedStatus, callbackResults.onVerified, t)
+}
+
+func TestMessageVerificationNoVerifierFailed(t *testing.T) {
+	callbackResults := runScenario(t, "testdata/mime/scenario_23.asc")
+	var expectedErrors = []SignatureVerificationError{newSignatureNoVerifier(), newSignatureFailed()}
+	compareErrors(expectedErrors, callbackResults.onError, t)
+	expectedStatus := []int{3}
+	compareStatus(expectedStatus, callbackResults.onVerified, t)
+}

crypto/signature_collector.go

@@ -7,6 +7,8 @@ import (
 	"mime"
 	"net/textproto"
 
+	pgpErrors "github.com/ProtonMail/go-crypto/openpgp/errors"
+
 	"github.com/ProtonMail/go-crypto/openpgp"
 	"github.com/ProtonMail/go-crypto/openpgp/packet"
 	gomime "github.com/ProtonMail/go-mime"
@@ -40,6 +42,7 @@ func (sc *SignatureCollector) Accept(
 	parentMediaType, params, _ := mime.ParseMediaType(header.Get("Content-Type"))
 
 	if parentMediaType != "multipart/signed" {
+		sc.verified = newSignatureNotSigned()
 		return sc.target.Accept(part, header, hasPlainSibling, isFirst, isLast)
 	}
 
@@ -97,12 +100,15 @@ func (sc *SignatureCollector) Accept(
 	str, _ := ioutil.ReadAll(rawBody)
 	rawBody = bytes.NewReader(str)
 	if sc.keyring != nil {
-		_, err = openpgp.CheckArmoredDetachedSignature(sc.keyring, rawBody, bytes.NewReader(buffer), sc.config)
+		_, err := openpgp.CheckArmoredDetachedSignature(sc.keyring, rawBody, bytes.NewReader(buffer), sc.config)
 
-		if err != nil {
+		switch {
-			sc.verified = newSignatureFailed()
+		case err == nil:
-		} else {
 			sc.verified = nil
+		case errors.Is(err, pgpErrors.ErrUnknownIssuer):
+			sc.verified = newSignatureNoVerifier()
+		default:
+			sc.verified = newSignatureFailed()
 		}
 	} else {
 		sc.verified = newSignatureNoVerifier()

crypto/testdata/mime/decryption-key.asc

@@ -0,0 +1,19 @@
+-----BEGIN PGP PRIVATE KEY BLOCK-----
+Comment: https://gopenpgp.org
+Version: GopenPGP 2.3.0
+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+=36V+
+-----END PGP PRIVATE KEY BLOCK-----

crypto/testdata/mime/scenario_00.asc

@@ -0,0 +1,39 @@
+-----BEGIN PGP MESSAGE-----
+Comment: https://gopenpgp.org
+Version: GopenPGP 2.3.0
+
+wV4DJ5XBV9zAEI0SAQdAbYuSz3T/ImbvCxy27lmThFtUM6N2ptgm0vDKVqlwUj8w
+mfvEZjgyj09JdEDP1rKTJxQAogpq1P6z9kcREgc+qR39yW+H32IQF4O8ezAJnlNK
+0uoBq8vMnuyqk0BOloOvDJAATKdXX9DVb7tbv5fmVeKEkvXfONl+2jASsKnjEdmf
+U4bIaPjpT89X6hOLPLsWcVoHgQQlN9M2R3Euff/0K6Pv1/20aLtXaAdIEajo4gdZ
+qWXGGhn+3qQ4PJvCuWwcwZ51oyTVlek/BVuCx+MazB159JQAPo5P2+f6Dp1Vv9K7
+XS0uJ7e9ThakqoFvWYigbdFoCzqCmVfQjF3VOYgJ2Gp1Q0Bd+cFbtoyTpaRCwAq+
+7TsIUqt5ZTKoMUI7Hx5NwoaWimiavfof4Ay/K/sH7jSYOGfQHhwIHxM5Cb3tfnSw
+CkHg+As0nIJxUWyHW2IhoHhpBwv11Kv2hJrFgzUpv7E4cuVT/LWNMjM7KAOsLMjP
+Cn3uD4tqn7AcXeOxHP438VAF34eAkaJkFA+zsW15Pj3eHQNlmtMc+U/XYBKh6few
+gyyO0lAqoDy25/cp16fFoz2orp6gTNyZj6gAeUy1AYlUdQ9mrUUCwizS6FiK+tIE
+u+VHA7OoslaNx/bL12/X8tk/3jMP5gxcItptW6XVa9w0HjHFKO1JGv+vUEHg7zAI
+Ojp7Azqlmi3Xs33FNqV7M4bPZZ/lKlvsgiPoDYQURPLQI6mrhgqaDOF8g++Xf0DE
+8Qo941m71PKgIL5oc3I1VgnXcY+sxLepJOWyB0Z9iv4/OLUDKpXuP0wAg1dYP/6k
+fG6L6mqIAcwkSSw5oSwGeua6aJDESrZIU3I7MZ4ctfmJutnEnxVTl3seRh7Dw0yF
+AIrPuiIfyTxSaEGUJYOjkNApHPS/CdQEdYmKhyxNbkUcTsdxRLmG8oF+fGUyXNn3
+YNfRkVVKhGTOv8yQBgC6qeA6Yf/2PR+Ejf+gtvPuVUIUN6TB1vwD7jmx6VuGSrdA
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+kWgU3J7YRrgky/FDv8NWEmRSdjnUG8CRXD56m91soDDJpHJ/2a7S8k/yBcDWxJs7
+WJORuovcykJsFcgMRY5t1TZL/p85ivDauwON688D8CXZHJqPrCckV1cvAI4SC5O6
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+ovxyHybQkMLi081/KlagA3+XpUa31PftWuhTtIdexSSLHQXI9NcbAdmORclKJAEM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+=WgDf
+-----END PGP MESSAGE-----

crypto/testdata/mime/scenario_01.asc

@@ -0,0 +1,23 @@
+-----BEGIN PGP MESSAGE-----
+Version: GopenPGP 2.3.0
+Comment: https://gopenpgp.org
+
+wV4DJ5XBV9zAEI0SAQdAZX1wJ562piYWaoZTb5faVaKchbb4yhyMc7ONPQJofgMw
+p9oSNLM8OYK7SwmSbLL5zYO4FMhYPAVyY1ENYKYT6yiu2WOaWIAtLpqWkj/2d0tX
+0ukB/U4jflL9Dn5i4ZVtiShsoEIpL0Q3zb5rPnqIRoaociOEDP/+g2BMv/sPk14x
++uyhM4fzNr1Sjbc39FppRv2ffkg4rc8s6mE7M51aiExfvhUddccSNPIUiSMAiz4q
+4ICTONeV7iD/cXg0vp23AcVxhz4tpMyyEY/k1yykukGkwHA3IgozKwn6cypAq1pQ
+H6hil/BPErQT/NcA1HNO9KJtKTeGsku2InCeuxP3LKPomf2lqR1FCRYfrC1Jh5mO
+oPvOrtWVF4oJSaF6u/xMOiThkKRiVUbw4vI95VrvFep7rGAJIQHcvzwX4mDYI5rh
+CsmpTSILtdbAs/DH5bI8bn+aO53GaCto9NDDRmVr7GqJ87kHSzW2Z9zQPlBTP3VR
+pLWsLDqz9DTprGgfSB9TdwenxaezXbc5mky9TMRrTqIdUxCEvUjd9n1RKRrzn6bY
+JLC4s/iNgXkopig21IQvD1FfBcnix3xtDAMT9pjDY6AYLgIhSOhJoH8+DX3qBPsF
+lQVbRHe7ExRLCJon8RgXReSquG/vQDcWFX8/SJJEbqtAO8XSbdFB+3pAWoYH+B4d
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+-----END PGP MESSAGE-----

crypto/testdata/mime/scenario_02.asc

@@ -0,0 +1,39 @@
+-----BEGIN PGP MESSAGE-----
+Version: GopenPGP 2.3.0
+Comment: https://gopenpgp.org
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+-----END PGP MESSAGE-----

crypto/testdata/mime/scenario_03.asc

@@ -0,0 +1,39 @@
+-----BEGIN PGP MESSAGE-----
+Version: GopenPGP 2.3.0
+Comment: https://gopenpgp.org
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crypto/testdata/mime/scenario_10.asc

@@ -0,0 +1,36 @@
+-----BEGIN PGP MESSAGE-----
+Version: GopenPGP 2.3.0
+Comment: https://gopenpgp.org
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crypto/testdata/mime/scenario_11.asc

@@ -0,0 +1,20 @@
+-----BEGIN PGP MESSAGE-----
+Version: GopenPGP 2.3.0
+Comment: https://gopenpgp.org
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crypto/testdata/mime/scenario_12.asc

@@ -0,0 +1,36 @@
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+Version: GopenPGP 2.3.0
+Comment: https://gopenpgp.org
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+-----END PGP MESSAGE-----

crypto/testdata/mime/scenario_13.asc

@@ -0,0 +1,36 @@
+-----BEGIN PGP MESSAGE-----
+Version: GopenPGP 2.3.0
+Comment: https://gopenpgp.org
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+-----END PGP MESSAGE-----

crypto/testdata/mime/scenario_20.asc

@@ -0,0 +1,39 @@
+-----BEGIN PGP MESSAGE-----
+Version: GopenPGP 2.3.0
+Comment: https://gopenpgp.org
+
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+-----END PGP MESSAGE-----

crypto/testdata/mime/scenario_21.asc

@@ -0,0 +1,23 @@
+-----BEGIN PGP MESSAGE-----
+Version: GopenPGP 2.3.0
+Comment: https://gopenpgp.org
+
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+-----END PGP MESSAGE-----

crypto/testdata/mime/scenario_22.asc

@@ -0,0 +1,39 @@
+-----BEGIN PGP MESSAGE-----
+Version: GopenPGP 2.3.0
+Comment: https://gopenpgp.org
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+-----END PGP MESSAGE-----

crypto/testdata/mime/scenario_23.asc

@@ -0,0 +1,39 @@
+-----BEGIN PGP MESSAGE-----
+Version: GopenPGP 2.3.0
+Comment: https://gopenpgp.org
+
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+-----END PGP MESSAGE-----

crypto/testdata/mime/verification-key.asc

@@ -0,0 +1,15 @@
+-----BEGIN PGP PUBLIC KEY BLOCK-----
+Version: GopenPGP 2.3.0
+Comment: https://gopenpgp.org
+
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+-----END PGP PUBLIC KEY BLOCK-----