From 7bc000b61f2d168b74b5f62344403b3667afbc84 Mon Sep 17 00:00:00 2001
From: Richard Ramos <info@richardramos.me>
Date: Mon, 20 Feb 2023 12:23:25 -0400
Subject: [PATCH] fix: use url-safe base64 encoding for noise

---
 waku/v2/protocol/noise/qr.go | 34 +++++++++++++++++++++++-----------
 1 file changed, 23 insertions(+), 11 deletions(-)

diff --git a/waku/v2/protocol/noise/qr.go b/waku/v2/protocol/noise/qr.go
index 7cb98822..1b9885c5 100644
--- a/waku/v2/protocol/noise/qr.go
+++ b/waku/v2/protocol/noise/qr.go
@@ -2,7 +2,7 @@ package noise
 
 import (
 	"crypto/ed25519"
-	b64 "encoding/base64"
+	"encoding/base64"
 	"errors"
 	"strings"
 )
@@ -27,17 +27,29 @@ func NewQR(applicationName, applicationVersion, shardId string, ephemeralKey ed2
 
 // Serializes input parameters to a base64 string for exposure through QR code (used by WakuPairing)
 func (qr QR) String() string {
-	return b64.StdEncoding.EncodeToString([]byte(qr.applicationName)) + ":" +
-		b64.StdEncoding.EncodeToString([]byte(qr.applicationVersion)) + ":" +
-		b64.StdEncoding.EncodeToString([]byte(qr.shardId)) + ":" +
-		b64.StdEncoding.EncodeToString(qr.ephemeralPublicKey) + ":" +
-		b64.StdEncoding.EncodeToString(qr.committedStaticKey[:])
+	return base64.URLEncoding.EncodeToString([]byte(qr.applicationName)) + ":" +
+		base64.URLEncoding.EncodeToString([]byte(qr.applicationVersion)) + ":" +
+		base64.URLEncoding.EncodeToString([]byte(qr.shardId)) + ":" +
+		base64.URLEncoding.EncodeToString(qr.ephemeralPublicKey) + ":" +
+		base64.URLEncoding.EncodeToString(qr.committedStaticKey[:])
 }
 
 func (qr QR) Bytes() []byte {
 	return []byte(qr.String())
 }
 
+func decodeBase64String(inputValue string) ([]byte, error) {
+	enc := base64.StdEncoding
+	if strings.ContainsAny(inputValue, "-_") {
+		enc = base64.URLEncoding
+	}
+	if len(inputValue)%4 != 0 {
+		enc = enc.WithPadding(base64.NoPadding)
+	}
+
+	return enc.DecodeString(inputValue)
+}
+
 // Deserializes input string in base64 to the corresponding (applicationName, applicationVersion, shardId, ephemeralKey, committedStaticKey)
 func StringToQR(qrString string) (QR, error) {
 	values := strings.Split(qrString, ":")
@@ -45,27 +57,27 @@ func StringToQR(qrString string) (QR, error) {
 		return QR{}, errors.New("invalid qr string")
 	}
 
-	applicationName, err := b64.StdEncoding.DecodeString(values[0])
+	applicationName, err := decodeBase64String(values[0])
 	if err != nil {
 		return QR{}, err
 	}
 
-	applicationVersion, err := b64.StdEncoding.DecodeString(values[1])
+	applicationVersion, err := decodeBase64String(values[1])
 	if err != nil {
 		return QR{}, err
 	}
 
-	shardId, err := b64.StdEncoding.DecodeString(values[2])
+	shardId, err := decodeBase64String(values[2])
 	if err != nil {
 		return QR{}, err
 	}
 
-	ephemeralKey, err := b64.StdEncoding.DecodeString(values[3])
+	ephemeralKey, err := decodeBase64String(values[3])
 	if err != nil {
 		return QR{}, err
 	}
 
-	committedStaticKey, err := b64.StdEncoding.DecodeString(values[4])
+	committedStaticKey, err := decodeBase64String(values[4])
 	if err != nil {
 		return QR{}, err
 	}