From 441589fa43b4af606dc3e36ee24624e9bc17fb09 Mon Sep 17 00:00:00 2001
From: Matthias Kruk <m@m10k.eu>
Date: Sat, 19 Nov 2022 19:44:16 +0900
Subject: [PATCH] include/queue: Base64-encoded data in queues

Queues are line-oriented, but the queue functions do not make sure
that user data does not contain newlines, causing data corruption
if the user inserts data that contains newlines.

This commit modifies the queue to store data in base64 format,
avoiding data-dependent behavior.
---
 include/queue.sh | 24 ++++++++++++++++++++----
 1 file changed, 20 insertions(+), 4 deletions(-)

diff --git a/include/queue.sh b/include/queue.sh
index dd592db..0aed18d 100644
--- a/include/queue.sh
+++ b/include/queue.sh
@@ -186,6 +186,7 @@ queue_put() {
 	local mutex
 	local sem
 	local data
+	local encoded_item
 	local err
 
 	mutex=$(_queue_get_mutex "$queue")
@@ -193,9 +194,13 @@ queue_put() {
 	data=$(_queue_get_data "$queue")
 	err=0
 
+	if ! encoded_item=$(base64 -w 0 <<< "$item"); then
+		return 1
+	fi
+
 	mutex_lock "$mutex"
 
-	if ! echo "$item" >> "$data"; then
+	if ! echo "$encoded_item" >> "$data"; then
 		err=1
 	fi
 
@@ -217,6 +222,7 @@ queue_get() {
 	local sem
 	local mutex
 	local data
+	local encoded_item
 	local item
 	local err
 
@@ -236,7 +242,7 @@ queue_get() {
 
 	mutex_lock "$mutex"
 
-	if ! item=$(head -n 1 "$data" 2>/dev/null); then
+	if ! encoded_item=$(head -n 1 "$data" 2>/dev/null); then
 		err=true
 	else
 		if ! sed -i '1d' "$data" &>/dev/null; then
@@ -250,6 +256,10 @@ queue_get() {
 		return 1
 	fi
 
+	if ! item=$(base64 -d <<< "$encoded_item"); then
+		return 1
+	fi
+
 	echo "$item"
 	return 0
 }
@@ -261,7 +271,7 @@ queue_foreach() {
 
 	local data
 	local mutex
-	local item
+	local encoded_item
 	local err
 
 	data=$(_queue_get_data "$name")
@@ -273,7 +283,13 @@ queue_foreach() {
 	fi
 
 	if [ -f "$data" ]; then
-		while read -r item; do
+		while read -r encoded_item; do
+			local item
+
+			if ! item=$(base64 -d <<< "$encoded_item"); then
+				continue
+			fi
+
 			if ! "$func" "$item" "${args[@]}"; then
 				err=1
 				break
-- 
2.47.3