Merge pull request #1350 from cyxc1124/fix/1344-preserve-crontab

fix(cron): 防止权限或读取失败清空 crontab

scripts/libs/set_cron.sh

@@ -1,41 +1,95 @@
-
 crondir="$(crond -h 2>&1 | grep -oE 'Default:.*' | awk -F ":" '{print $2}'| tr -d ' ')"
 [ ! -w "$crondir" ] && crondir="/etc/storage/cron/crontabs"
 [ ! -w "$crondir" ] && crondir="/var/spool/cron/crontabs"
 [ ! -w "$crondir" ] && crondir="/var/spool/cron"
-[ -z "$USER" ] && USER=$(whoami 2>/dev/null)
+[ -z "$USER" ] && USER=$(id -un)
 [ -z "$TASKCFGDIR" ] && TASKCFGDIR="$CRASHDIR"/configs/task
-tmpcron=/tmp/cron_tmp
-touch "$tmpcron"
 
-cronadd() { #定时任务工具
+# ShellCrash 使用的 ash/bash（以及 dash）均支持 test -O。
-    if crontab -h 2>&1 | grep -q '\-l'; then
+# shellcheck disable=SC3067
-        crontab "$1"
+croncheck() { #在任何写操作前检查实例管理权限，保留普通用户自己的安装
-    elif [ -w "$crondir" ];then
+    cron_uid=$(id -u) || return 1
-        cat "$1" >"$crondir"/"$USER" && cru a REFRESH "0 0 1 1 * /bin/true" 2>/dev/null
+    [ "$cron_uid" = 0 ] && return 0
-    else
+    if [ ! -O "$CRASHDIR/configs/ShellCrash.cfg" ] || [ ! -w "$CRASHDIR/configs/ShellCrash.cfg" ]; then
-        echo "找不到可用的crond或者crontab应用！No available crond or crontab application can be found!"
+        echo '无权管理此 ShellCrash 实例，请使用安装用户或 root。' >&2
-    fi
-}
-cronload() { #定时任务工具
-    if crontab -h 2>&1 | grep -q '\-l'; then
-        crontab -l
-    elif [ -f "$crondir/$USER" ];then
-        cat "$crondir"/"$USER" 2>/dev/null
-    else
         return 1
     fi
-}
+    for cron_pid in $(pidof CrashCore 2>/dev/null); do
-cronset() { #定时任务设置
+        if [ ! -O "/proc/$cron_pid" ]; then
-    # 参数1代表要移除的关键字,参数2代表要添加的任务语句
+            echo '无权管理其他用户启动的 CrashCore。' >&2
-    cronload | grep -v '^$' | grep -vF "$1" >"$tmpcron"
+            return 1
-    [ -n "$2" ] && echo "$2" >>"$tmpcron"
-    cronadd "$tmpcron"
-    #华硕/Padavan固件存档在本地,其他则删除
-    if [ -d /jffs ] || [ -d /etc/storage/ShellCrash ];then
-        mkdir -p "$TASKCFGDIR"
-        mv -f "$tmpcron" "$TASKCFGDIR"/cron
-    else
-        rm -f "$tmpcron"
         fi
+    done
 }
+
+cronadd() ( #定时任务工具；子 shell 隔离临时变量和清理 trap
+    croncheck || exit 1
+    [ -f "$1" ] && [ -r "$1" ] || exit 1
+    if crontab -h 2>&1 | grep -q '\-l'; then
+        crontab "$1"
+    elif [ -w "$crondir" ]; then
+        cron_user=$(id -un) || exit 1
+        cron_stage=$(mktemp "$crondir/.shellcrash.XXXXXX") || exit 1
+        trap 'rm -f "$cron_stage"' 0
+        trap 'exit 1' 1 2 3 15
+        [ ! -e "$crondir/$cron_user" ] || cp -p "$crondir/$cron_user" "$cron_stage" || exit 1
+        cat "$1" >"$cron_stage" && mv -f "$cron_stage" "$crondir/$cron_user" || exit 1
+        if command -v cru >/dev/null 2>&1; then
+            cru a REFRESH "0 0 1 1 * /bin/true"
+        fi
+    else
+        echo '找不到可用的 crond 或 crontab！No available crond or crontab!' >&2
+        exit 1
+    fi
+)
+
+cronload() (
+    cron_user=$(id -un) || exit 1
+    if crontab -h 2>&1 | grep -q '\-l'; then
+        cron_text=$(LC_ALL=C crontab -l 2>&1)
+        cron_status=$?
+        if [ "$cron_status" = 0 ]; then
+            [ -z "$cron_text" ] || printf '%s\n' "$cron_text"
+            exit 0
+        fi
+        #首次使用没有 crontab 是合法空表，其他错误必须传回调用者。
+        case "$cron_text" in
+            "no crontab for $cron_user" | "crontab: can't open '$cron_user': No such file or directory") exit 0 ;;
+        esac
+        printf '%s\n' "$cron_text" >&2
+        exit "$cron_status"
+    elif [ -d "$crondir" ] && [ -r "$crondir" ] && [ -x "$crondir" ]; then
+        [ -e "$crondir/$cron_user" ] || [ -L "$crondir/$cron_user" ] || exit 0
+        cat "$crondir/$cron_user"
+    else
+        echo '无法读取原有 crontab，已取消修改。' >&2
+        exit 1
+    fi
+)
+
+cronupdate() ( #成功读取、生成后才提交；参数是读取 stdin 的过滤命令
+    croncheck || exit 1
+    cron_tmp=$(mktemp -d /tmp/ShellCrash-cron.XXXXXX) || exit 1
+    cron_saved=
+    trap 'rm -rf "$cron_tmp"; [ -z "$cron_saved" ] || rm -f "$cron_saved"' 0
+    trap 'exit 1' 1 2 3 15
+    cronload >"$cron_tmp/old" || exit 1
+    "$@" <"$cron_tmp/old" >"$cron_tmp/new" || exit 1
+    #先准备华硕/Padavan 的持久化副本；任何提交前的写入失败都保留原表。
+    if [ "$cron_persist" = true ] && { [ -d /jffs ] || [ -d /etc/storage/ShellCrash ]; }; then
+        mkdir -p "$TASKCFGDIR" || exit 1
+        cron_saved=$(mktemp "$TASKCFGDIR/.cron.XXXXXX") || exit 1
+        cat "$cron_tmp/new" >"$cron_saved" || exit 1
+    fi
+    cronadd "$cron_tmp/new" || exit 1
+    [ -z "$cron_saved" ] || mv -f "$cron_saved" "$TASKCFGDIR/cron"
+)
+
+cronset() ( #参数1：移除的文字；参数2：新增任务。空结果也是合法 crontab。
+    cron_persist=true
+    # shellcheck disable=SC2016
+    CRON_KEY="$1" CRON_TASK="$2" cronupdate awk '
+        NF && !index($0, ENVIRON["CRON_KEY"]) { print }
+        END { if (ENVIRON["CRON_TASK"] != "") print ENVIRON["CRON_TASK"] }
+    '
+)

scripts/start.sh

@@ -6,10 +6,11 @@
     cd $(dirname $0)
     pwd
 )
+. "$CRASHDIR"/libs/set_cron.sh
+croncheck || exit 1
 . "$CRASHDIR"/libs/get_config.sh
 #加载工具
 . "$CRASHDIR"/libs/set_config.sh
-. "$CRASHDIR"/libs/set_cron.sh
 . "$CRASHDIR"/libs/check_cmd.sh
 . "$CRASHDIR"/libs/check_autostart.sh
 . "$CRASHDIR"/libs/compare.sh
@@ -36,7 +37,9 @@ start_l(){
 case "$1" in
 
 start)
-    [ -n "$(pidof CrashCore)" ] && $0 stop #禁止多实例
+    if [ -n "$(pidof CrashCore)" ]; then #禁止多实例
+        "$0" stop || exit 1
+    fi
     stop_firewall                          #清理路由策略
     rm -f "$CRASHDIR"/\.start_error #移除自启失败标记
     #使用不同方式启动服务
@@ -69,9 +72,7 @@ stop)
     logger ShellCrash服务即将关闭......
     [ -n "$(pidof CrashCore)" ] && web_save #保存面板配置
     #清理定时任务
-    cronload | grep -vE '^$|start_legacy_wd.sh|运行时每' > "$TMPDIR"/cron_tmp
+    cronupdate awk 'NF && !/start_legacy_wd.sh|运行时每/' || exit 1
-    cronadd "$TMPDIR"/cron_tmp
-    rm -f "$TMPDIR"/cron_tmp
     #停止tg_bot
     . "$CRASHDIR"/menus/bot_tg_service.sh && bot_tg_stop
     #多种方式结束进程
@@ -96,8 +97,7 @@ stop)
     rm -rf "$TMPDIR"/CrashCore
     ;;
 restart)
-    $0 stop
+    "$0" stop && "$0" start
-    $0 start
     ;;
 init)
     . "$CRASHDIR"/starts/general_init.sh
@@ -110,7 +110,9 @@ daemon)
     fi
     ;;
 debug)
-    [ -n "$(pidof CrashCore)" ] && $0 stop >/dev/null #禁止多实例
+    if [ -n "$(pidof CrashCore)" ]; then #禁止多实例
+        "$0" stop >/dev/null || exit 1
+    fi
     stop_firewall >/dev/null                          #清理路由策略
     bfstart
     if [ -n "$2" ]; then

scripts/starts/afstart.sh

@@ -7,11 +7,12 @@
 	cd ..
 	pwd
 )
+. "$CRASHDIR"/libs/set_cron.sh
+croncheck || exit 1
 . "$CRASHDIR"/libs/get_config.sh
 #加载工具
 . "$CRASHDIR"/libs/check_cmd.sh
 . "$CRASHDIR"/libs/logger.sh
-. "$CRASHDIR"/libs/set_cron.sh
 #缺省值
 [ -z "$firewall_area" ] && firewall_area=1
 #延迟启动
@@ -37,14 +38,24 @@ if [ -n "$test" -o -n "$(pidof CrashCore)" ]; then
 	} &
 	ckcmd mtd_storage.sh && mtd_storage.sh save >/dev/null 2>&1 #Padavan保存/etc/storage
 	#加载定时任务
-	cronload | grep -v '^$' >"$TMPDIR"/cron_tmp
+	set -- -
-	[ -s "$TASKCFGDIR"/cron ] && cat "$TASKCFGDIR"/cron >>"$TMPDIR"/cron_tmp
+	for cron_file in "$TASKCFGDIR/cron" "$TASKCFGDIR/running"; do
-	[ -s "$TASKCFGDIR"/running ] && cat "$TASKCFGDIR"/running >>"$TMPDIR"/cron_tmp
+		[ ! -e "$cron_file" ] || set -- "$@" "$cron_file"
-	[ "$bot_tg_service" = ON ] && echo "* * * * * /bin/sh $CRASHDIR/starts/start_legacy_wd.sh bot_tg #ShellCrash-TG_BOT守护进程" >>"$TMPDIR"/cron_tmp
+	done
-	[ "$start_old" = ON ] && echo "* * * * * /bin/sh $CRASHDIR/starts/start_legacy_wd.sh shellcrash #ShellCrash保守模式守护进程" >>"$TMPDIR"/cron_tmp
+	# shellcheck disable=SC2016
-	awk '!x[$0]++' "$TMPDIR"/cron_tmp >"$TMPDIR"/cron_tmp2 #删除重复行
+	CRON_BOT="$bot_tg_service" CRON_LEGACY="$start_old" CRON_DIR="$CRASHDIR" cronupdate awk '
-	cronadd "$TMPDIR"/cron_tmp2
+		NF && !seen[$0]++ { print }
-	rm -f "$TMPDIR"/cron_tmp "$TMPDIR"/cron_tmp2
+		END {
+			if (ENVIRON["CRON_BOT"] == "ON") {
+				line = "* * * * * /bin/sh " ENVIRON["CRON_DIR"] "/starts/start_legacy_wd.sh bot_tg #ShellCrash-TG_BOT守护进程"
+				if (!seen[line]++) print line
+			}
+			if (ENVIRON["CRON_LEGACY"] == "ON") {
+				line = "* * * * * /bin/sh " ENVIRON["CRON_DIR"] "/starts/start_legacy_wd.sh shellcrash #ShellCrash保守模式守护进程"
+				if (!seen[line]++) print line
+			}
+		}
+	' "$@" || exit 1
 	#加载条件任务
 	[ -s "$TASKCFGDIR"/afstart ] && { . "$TASKCFGDIR"/afstart; } &
 	[ -s "$TASKCFGDIR"/affirewall -a -s /etc/init.d/firewall -a ! -f /etc/init.d/firewall.bak ] && {

scripts/starts/snapshot_init.sh

@@ -4,7 +4,6 @@
 CRASHDIR="$(uci get firewall.ShellCrash.path | sed 's/\/starts.*//')"
 #防止提前自启
 /etc/init.d/shellcrash disable
-crontab -l | grep -v 'start_legacy_wd.sh shellcrash' | crontab -
 #防止usb未加载
 i=0
 while [ ! -f "$CRASHDIR/configs/ShellCrash.cfg" ]; do
@@ -13,6 +12,8 @@ while [ ! -f "$CRASHDIR/configs/ShellCrash.cfg" ]; do
     sleep 3
 done
 . "$CRASHDIR"/configs/ShellCrash.cfg
+. "$CRASHDIR"/libs/set_cron.sh
+cronset 'start_legacy_wd.sh shellcrash' || exit 1
 
 autoSSH() {
     #自动开启SSH