more fixes and tweaks to keyer, 17, 44 and 59.

keyer/plain.go

@@ -18,9 +18,10 @@ type KeySigner struct {
 func (ks KeySigner) SignEvent(ctx context.Context, evt *nostr.Event) error { return evt.Sign(ks.sk) }
 func (ks KeySigner) GetPublicKey(ctx context.Context) string               { return ks.pk }
 
-func (ks KeySigner) Encrypt(ctx context.Context, plaintext string, recipient string) (c64 string, err error) {
+func (ks KeySigner) Encrypt(ctx context.Context, plaintext string, recipient string) (string, error) {
 	ck, ok := ks.conversationKeys[recipient]
 	if !ok {
+		var err error
 		ck, err = nip44.GenerateConversationKey(recipient, ks.sk)
 		if err != nil {
 			return "", err
@@ -30,7 +31,7 @@ func (ks KeySigner) Encrypt(ctx context.Context, plaintext string, recipient str
 	return nip44.Encrypt(plaintext, ck)
 }
 
-func (ks KeySigner) Decrypt(ctx context.Context, base64ciphertext string, sender string) (plaintext string, err error) {
+func (ks KeySigner) Decrypt(ctx context.Context, base64ciphertext string, sender string) (string, error) {
 	ck, ok := ks.conversationKeys[sender]
 	if !ok {
 		var err error
@@ -40,5 +41,5 @@ func (ks KeySigner) Decrypt(ctx context.Context, base64ciphertext string, sender
 		}
 		ks.conversationKeys[sender] = ck
 	}
-	return nip44.Encrypt(plaintext, ck)
+	return nip44.Decrypt(base64ciphertext, ck)
 }

nip17/nip17.go

@@ -37,23 +37,30 @@ func PrepareMessage(
 	kr keyer.Keyer,
 	recipientPubKey string,
 	modify func(*nostr.Event),
-) (nostr.Event, error) {
+) (toUs nostr.Event, toThem nostr.Event, err error) {
+	ourPubkey := kr.GetPublicKey(ctx)
+
 	rumor := nostr.Event{
 		Kind:      14,
 		Content:   content,
 		Tags:      tags,
 		CreatedAt: nostr.Now(),
-		PubKey:    kr.GetPublicKey(ctx),
+		PubKey:    ourPubkey,
 	}
 	rumor.ID = rumor.GetID()
 
-	return nip59.GiftWrap(
+	wraps, err := nip59.GiftWrap(
 		rumor,
-		recipientPubKey,
+		[]string{ourPubkey, recipientPubKey},
 		func(s string) (string, error) { return kr.Encrypt(ctx, s, recipientPubKey) },
 		func(e *nostr.Event) error { return kr.SignEvent(ctx, e) },
 		modify,
 	)
+	if err != nil {
+		return nostr.Event{}, nostr.Event{}, err
+	}
+
+	return wraps[0], wraps[1], nil
 }
 
 // ListenForMessages returns a channel with the rumors already decrypted and checked

nip44/nip44_test.go

@@ -5,189 +5,108 @@ import (
 	"crypto/sha256"
 	"encoding/hex"
 	"fmt"
-	"hash"
 	"strings"
 	"testing"
 
 	"github.com/nbd-wtf/go-nostr"
-	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 func assertCryptPriv(t *testing.T, sk1 string, sk2 string, conversationKey string, salt string, plaintext string, expected string) {
-	var (
-		k1        [32]byte
-		s         []byte
-		actual    string
-		decrypted string
-		ok        bool
-		err       error
-	)
-	k1, err = hexDecode32Array(conversationKey)
-	if ok = assert.NoErrorf(t, err, "hex decode failed for conversation key: %v", err); !ok {
-		return
-	}
-	if ok = assertConversationKeyGenerationSec(t, sk1, sk2, conversationKey); !ok {
-		return
-	}
-	s, err = hex.DecodeString(salt)
-	if ok = assert.NoErrorf(t, err, "hex decode failed for salt: %v", err); !ok {
-		return
-	}
-	actual, err = Encrypt(plaintext, k1, WithCustomNonce(s))
-	if ok = assert.NoError(t, err, "encryption failed: %v", err); !ok {
-		return
-	}
-	if ok = assert.Equalf(t, expected, actual, "wrong encryption"); !ok {
-		return
-	}
-	decrypted, err = Decrypt(expected, k1)
-	if ok = assert.NoErrorf(t, err, "decryption failed: %v", err); !ok {
-		return
-	}
-	assert.Equal(t, decrypted, plaintext, "wrong decryption")
+	k1, err := hexDecode32Array(conversationKey)
+	require.NoErrorf(t, err, "hex decode failed for conversation key: %v", err)
+	assertConversationKeyGenerationSec(t, sk1, sk2, conversationKey)
+
+	customNonce, err := hex.DecodeString(salt)
+	require.NoErrorf(t, err, "hex decode failed for salt: %v", err)
+
+	actual, err := Encrypt(plaintext, k1, WithCustomNonce(customNonce))
+	require.NoError(t, err, "encryption failed: %v", err)
+	require.Equalf(t, expected, actual, "wrong encryption")
+
+	decrypted, err := Decrypt(expected, k1)
+	require.NoErrorf(t, err, "decryption failed: %v", err)
+
+	require.Equal(t, decrypted, plaintext, "wrong decryption")
 }
 
 func assertDecryptFail(t *testing.T, conversationKey string, _ string, ciphertext string, msg string) {
-	var (
-		k1  [32]byte
-		ok  bool
-		err error
-	)
-	k1, err = hexDecode32Array(conversationKey)
-	if ok = assert.NoErrorf(t, err, "hex decode failed for conversation key: %v", err); !ok {
-		return
-	}
+	k1, err := hexDecode32Array(conversationKey)
+	require.NoErrorf(t, err, "hex decode failed for conversation key: %v", err)
+
 	_, err = Decrypt(ciphertext, k1)
-	assert.ErrorContains(t, err, msg)
+	require.ErrorContains(t, err, msg)
 }
 
 func assertConversationKeyFail(t *testing.T, priv string, pub string, msg string) {
 	_, err := GenerateConversationKey(pub, priv)
-	assert.ErrorContains(t, err, msg)
+	require.ErrorContains(t, err, msg)
 }
 
-func assertConversationKeyGeneration(t *testing.T, priv string, pub string, conversationKey string) bool {
-	var (
-		actualConversationKey   [32]byte
-		expectedConversationKey [32]byte
-		ok                      bool
-		err                     error
-	)
-	expectedConversationKey, err = hexDecode32Array(conversationKey)
-	if ok = assert.NoErrorf(t, err, "hex decode failed for conversation key: %v", err); !ok {
-		return false
-	}
-	actualConversationKey, err = GenerateConversationKey(pub, priv)
-	if ok = assert.NoErrorf(t, err, "conversation key generation failed: %v", err); !ok {
-		return false
-	}
-	if ok = assert.Equalf(t, expectedConversationKey, actualConversationKey, "wrong conversation key"); !ok {
-		return false
-	}
-	return true
+func assertConversationKeyGenerationPub(t *testing.T, priv string, pub string, conversationKey string) {
+	expectedConversationKey, err := hexDecode32Array(conversationKey)
+	require.NoErrorf(t, err, "hex decode failed for conversation key: %v", err)
+
+	actualConversationKey, err := GenerateConversationKey(pub, priv)
+	require.NoErrorf(t, err, "conversation key generation failed: %v", err)
+
+	require.Equalf(t, expectedConversationKey, actualConversationKey, "wrong conversation key")
 }
 
-func assertConversationKeyGenerationSec(t *testing.T, sk1 string, sk2 string, conversationKey string) bool {
+func assertConversationKeyGenerationSec(t *testing.T, sk1 string, sk2 string, conversationKey string) {
 	pub2, err := nostr.GetPublicKey(sk2)
-	if ok := assert.NoErrorf(t, err, "failed to derive pubkey from sk2: %v", err); !ok {
-		return false
-	}
-	return assertConversationKeyGeneration(t, sk1, pub2, conversationKey)
-}
-
-func assertConversationKeyGenerationPub(t *testing.T, sk string, pub string, conversationKey string) bool {
-	return assertConversationKeyGeneration(t, sk, pub, conversationKey)
+	require.NoErrorf(t, err, "failed to derive pubkey from sk2: %v", err)
+	assertConversationKeyGenerationPub(t, sk1, pub2, conversationKey)
 }
 
 func assertMessageKeyGeneration(t *testing.T, conversationKey string, salt string, chachaKey string, chachaSalt string, hmacKey string) bool {
-	var (
-		convKey             [32]byte
-		convSalt            []byte
-		actualChaChaKey     []byte
-		expectedChaChaKey   []byte
-		actualChaChaNonce   []byte
-		expectedChaChaNonce []byte
-		actualHmacKey       []byte
-		expectedHmacKey     []byte
-		ok                  bool
-		err                 error
-	)
-	convKey, err = hexDecode32Array(conversationKey)
-	if ok = assert.NoErrorf(t, err, "hex decode failed for convKey: %v", err); !ok {
-		return false
-	}
-	convSalt, err = hex.DecodeString(salt)
-	if ok = assert.NoErrorf(t, err, "hex decode failed for salt: %v", err); !ok {
-		return false
-	}
-	expectedChaChaKey, err = hex.DecodeString(chachaKey)
-	if ok = assert.NoErrorf(t, err, "hex decode failed for chacha key: %v", err); !ok {
-		return false
-	}
-	expectedChaChaNonce, err = hex.DecodeString(chachaSalt)
-	if ok = assert.NoErrorf(t, err, "hex decode failed for chacha nonce: %v", err); !ok {
-		return false
-	}
-	expectedHmacKey, err = hex.DecodeString(hmacKey)
-	if ok = assert.NoErrorf(t, err, "hex decode failed for hmac key: %v", err); !ok {
-		return false
-	}
-	actualChaChaKey, actualChaChaNonce, actualHmacKey, err = messageKeys(convKey, convSalt)
-	if ok = assert.NoErrorf(t, err, "message key generation failed: %v", err); !ok {
-		return false
-	}
-	if ok = assert.Equalf(t, expectedChaChaKey, actualChaChaKey, "wrong chacha key"); !ok {
-		return false
-	}
-	if ok = assert.Equalf(t, expectedChaChaNonce, actualChaChaNonce, "wrong chacha nonce"); !ok {
-		return false
-	}
-	if ok = assert.Equalf(t, expectedHmacKey, actualHmacKey, "wrong hmac key"); !ok {
-		return false
-	}
+	convKey, err := hexDecode32Array(conversationKey)
+	require.NoErrorf(t, err, "hex decode failed for convKey: %v", err)
+
+	convNonce, err := hexDecode32Array(salt)
+	require.NoErrorf(t, err, "hex decode failed for nonce: %v", err)
+
+	expectedChaChaKey, err := hex.DecodeString(chachaKey)
+	require.NoErrorf(t, err, "hex decode failed for chacha key: %v", err)
+
+	expectedChaChaNonce, err := hex.DecodeString(chachaSalt)
+	require.NoErrorf(t, err, "hex decode failed for chacha nonce: %v", err)
+
+	expectedHmacKey, err := hex.DecodeString(hmacKey)
+	require.NoErrorf(t, err, "hex decode failed for hmac key: %v", err)
+
+	actualChaChaKey, actualChaChaNonce, actualHmacKey, err := messageKeys(convKey, convNonce)
+	require.NoErrorf(t, err, "message key generation failed: %v", err)
+
+	require.Equalf(t, expectedChaChaKey, actualChaChaKey, "wrong chacha key")
+	require.Equalf(t, expectedChaChaNonce, actualChaChaNonce, "wrong chacha nonce")
+	require.Equalf(t, expectedHmacKey, actualHmacKey, "wrong hmac key")
 	return true
 }
 
 func assertCryptLong(t *testing.T, conversationKey string, salt string, pattern string, repeat int, plaintextSha256 string, payloadSha256 string) {
-	var (
-		convKey               [32]byte
-		convSalt              []byte
-		plaintext             string
-		actualPlaintextSha256 string
-		actualPayload         string
-		actualPayloadSha256   string
-		h                     hash.Hash
-		ok                    bool
-		err                   error
-	)
-	convKey, err = hexDecode32Array(conversationKey)
-	if ok = assert.NoErrorf(t, err, "hex decode failed for convKey: %v", err); !ok {
-		return
-	}
-	convSalt, err = hex.DecodeString(salt)
-	if ok = assert.NoErrorf(t, err, "hex decode failed for salt: %v", err); !ok {
-		return
-	}
-	plaintext = ""
+	convKey, err := hexDecode32Array(conversationKey)
+	require.NoErrorf(t, err, "hex decode failed for convKey: %v", err)
+
+	customNonce, err := hex.DecodeString(salt)
+	require.NoErrorf(t, err, "hex decode failed for salt: %v", err)
+
+	plaintext := ""
 	for i := 0; i < repeat; i++ {
 		plaintext += pattern
 	}
-	h = sha256.New()
+	h := sha256.New()
 	h.Write([]byte(plaintext))
-	actualPlaintextSha256 = hex.EncodeToString(h.Sum(nil))
-	if ok = assert.Equalf(t, plaintextSha256, actualPlaintextSha256, "invalid plaintext sha256 hash: %v", err); !ok {
-		return
-	}
-	actualPayload, err = Encrypt(plaintext, convKey, WithCustomNonce(convSalt))
-	if ok = assert.NoErrorf(t, err, "encryption failed: %v", err); !ok {
-		return
-	}
+	actualPlaintextSha256 := hex.EncodeToString(h.Sum(nil))
+	require.Equalf(t, plaintextSha256, actualPlaintextSha256, "invalid plaintext sha256 hash: %v", err)
+
+	actualPayload, err := Encrypt(plaintext, convKey, WithCustomNonce(customNonce))
+	require.NoErrorf(t, err, "encryption failed: %v", err)
+
 	h.Reset()
 	h.Write([]byte(actualPayload))
-	actualPayloadSha256 = hex.EncodeToString(h.Sum(nil))
-	if ok = assert.Equalf(t, payloadSha256, actualPayloadSha256, "invalid payload sha256 hash: %v", err); !ok {
-		return
-	}
+	actualPayloadSha256 := hex.EncodeToString(h.Sum(nil))
+	require.Equalf(t, payloadSha256, actualPayloadSha256, "invalid payload sha256 hash: %v", err)
 }
 
 func TestCryptPriv001(t *testing.T) {
@@ -1162,38 +1081,23 @@ func TestMaxLength(t *testing.T) {
 	)
 }
 
-func assertCryptPub(t *testing.T, sk1 string, pub2 string, conversationKey string, salt string, plaintext string, expected string) {
-	var (
-		k1        [32]byte
-		s         []byte
-		actual    string
-		decrypted string
-		ok        bool
-		err       error
-	)
-	k1, err = hexDecode32Array(conversationKey)
-	if ok = assert.NoErrorf(t, err, "hex decode failed for conversation key: %v", err); !ok {
-		return
-	}
-	if ok = assertConversationKeyGenerationPub(t, sk1, pub2, conversationKey); !ok {
-		return
-	}
-	s, err = hex.DecodeString(salt)
-	if ok = assert.NoErrorf(t, err, "hex decode failed for salt: %v", err); !ok {
-		return
-	}
-	actual, err = Encrypt(plaintext, k1, WithCustomNonce(s))
-	if ok = assert.NoError(t, err, "encryption failed: %v", err); !ok {
-		return
-	}
-	if ok = assert.Equalf(t, expected, actual, "wrong encryption"); !ok {
-		return
-	}
-	decrypted, err = Decrypt(expected, k1)
-	if ok = assert.NoErrorf(t, err, "decryption failed: %v", err); !ok {
-		return
-	}
-	assert.Equal(t, decrypted, plaintext, "wrong decryption")
+func assertCryptPub(t *testing.T, sk1 string, pub2 string, conversationKey string, customNonce string, plaintext string, expected string) {
+	k1, err := hexDecode32Array(conversationKey)
+	require.NoErrorf(t, err, "hex decode failed for conversation key: %v", err)
+
+	assertConversationKeyGenerationPub(t, sk1, pub2, conversationKey)
+
+	s, err := hex.DecodeString(customNonce)
+	require.NoErrorf(t, err, "hex decode failed for salt: %v", err)
+
+	actual, err := Encrypt(plaintext, k1, WithCustomNonce(s))
+	require.NoError(t, err, "encryption failed: %v", err)
+	require.Equalf(t, expected, actual, "wrong encryption")
+
+	decrypted, err := Decrypt(expected, k1)
+	require.NoErrorf(t, err, "decryption failed: %v", err)
+
+	require.Equal(t, decrypted, plaintext, "wrong decryption")
 }
 
 func hexDecode32Array(hexString string) (res [32]byte, err error) {

nip59/nip59.go

@@ -13,15 +13,15 @@ import (
 // signs that (after potentially applying a modify function, which can be nil otherwise), yielding a 'gift-wrap'.
 func GiftWrap(
 	rumor nostr.Event,
-	recipientPublicKey string,
+	recipients []string, // return one giftwrap addressed to each of these
 	encrypt func(plaintext string) (string, error),
 	sign func(*nostr.Event) error,
 	modify func(*nostr.Event),
-) (nostr.Event, error) {
+) ([]nostr.Event, error) {
 	rumor.Sig = ""
 	rumorCiphertext, err := encrypt(rumor.String())
 	if err != nil {
-		return nostr.Event{}, err
+		return nil, err
 	}
 
 	seal := nostr.Event{
@@ -31,37 +31,39 @@ func GiftWrap(
 		Tags:      make(nostr.Tags, 0),
 	}
 	if err := sign(&seal); err != nil {
-		return nostr.Event{}, err
+		return nil, err
 	}
 
-	nonceKey := nostr.GeneratePrivateKey()
-	temporaryConversationKey, err := nip44.GenerateConversationKey(recipientPublicKey, nonceKey)
-	if err != nil {
-		return nostr.Event{}, err
-	}
-	sealCiphertext, err := nip44.Encrypt(seal.String(), temporaryConversationKey)
-	if err != nil {
-		return nostr.Event{}, err
+	results := make([]nostr.Event, len(recipients))
+	for i, recipient := range recipients {
+		nonceKey := nostr.GeneratePrivateKey()
+		temporaryConversationKey, err := nip44.GenerateConversationKey(recipient, nonceKey)
+		if err != nil {
+			return nil, err
+		}
+		sealCiphertext, err := nip44.Encrypt(seal.String(), temporaryConversationKey)
+		if err != nil {
+			return nil, err
+		}
+
+		gw := nostr.Event{
+			Kind:      1059,
+			Content:   sealCiphertext,
+			CreatedAt: nostr.Now() - nostr.Timestamp(60*rand.Int63n(600) /* up to 6 hours in the past */),
+			Tags: nostr.Tags{
+				nostr.Tag{"p", recipient},
+			},
+		}
+		if modify != nil {
+			modify(&gw)
+		}
+		if err := gw.Sign(nonceKey); err != nil {
+			return nil, err
+		}
+		results[i] = gw
 	}
 
-	gw := nostr.Event{
-		Kind:      1059,
-		Content:   sealCiphertext,
-		CreatedAt: nostr.Now() - nostr.Timestamp(60*rand.Int63n(600) /* up to 6 hours in the past */),
-		Tags: nostr.Tags{
-			nostr.Tag{"p", recipientPublicKey},
-		},
-	}
-
-	if modify != nil {
-		modify(&gw)
-	}
-
-	if err := gw.Sign(nonceKey); err != nil {
-		return gw, err
-	}
-
-	return gw, nil
+	return results, nil
 }
 
 func GiftUnwrap(
@@ -70,13 +72,13 @@ func GiftUnwrap(
 ) (rumor nostr.Event, err error) {
 	jseal, err := decrypt(gw.PubKey, gw.Content)
 	if err != nil {
-		return rumor, err
+		return rumor, fmt.Errorf("failed to decrypt seal: %w", err)
 	}
 
 	var seal nostr.Event
 	err = easyjson.Unmarshal([]byte(jseal), &seal)
 	if err != nil {
-		return rumor, err
+		return rumor, fmt.Errorf("seal is invalid json: %w", err)
 	}
 
 	if ok, _ := seal.CheckSignature(); !ok {
@@ -85,12 +87,12 @@ func GiftUnwrap(
 
 	jrumor, err := decrypt(seal.PubKey, seal.Content)
 	if err != nil {
-		return rumor, err
+		return rumor, fmt.Errorf("failed to decrypt rumor: %w", err)
 	}
 
 	err = easyjson.Unmarshal([]byte(jrumor), &rumor)
 	if err != nil {
-		return rumor, err
+		return rumor, fmt.Errorf("rumor is invalid json: %w", err)
 	}
 
 	rumor.PubKey = seal.PubKey