Implement iptables forward manager core

lib/storage.sh

@@ -0,0 +1,123 @@
+#!/usr/bin/env bash
+
+if [[ -n ${IPF_STORAGE_SH_LOADED:-} ]]; then
+  return 0
+fi
+IPF_STORAGE_SH_LOADED=1
+
+: "${IPF_STORAGE_DIR:=/var/lib/iptables-forward}"
+: "${IPF_STORAGE_DB:=${IPF_STORAGE_DIR}/rules.db}"
+: "${IPF_LOCK_FILE:=${IPF_STORAGE_DIR}/.lock}"
+
+storage_dir() {
+  printf '%s\n' "${IPF_STORAGE_DIR}"
+}
+
+storage_db_path() {
+  printf '%s\n' "${IPF_STORAGE_DB}"
+}
+
+storage_lock_path() {
+  printf '%s\n' "${IPF_LOCK_FILE}"
+}
+
+storage_init() {
+  local dir db lock
+  dir=$(storage_dir)
+  db=$(storage_db_path)
+  lock=$(storage_lock_path)
+
+  mkdir -p "${dir}"
+  touch "${db}" "${lock}"
+  chmod 750 "${dir}"
+  chmod 640 "${db}"
+  chmod 600 "${lock}"
+}
+
+storage_add() {
+  local line=${1-}
+  local db lock
+  [[ -n ${line} ]] || return 1
+  storage_init
+  db=$(storage_db_path)
+  lock=$(storage_lock_path)
+
+  (
+    flock -x 9
+    printf '%s\n' "${line}" >>"${db}"
+  ) 9>>"${lock}"
+}
+
+storage_list() {
+  local db
+  db=$(storage_db_path)
+  [[ -f ${db} ]] || return 0
+  cat "${db}"
+}
+
+storage_parse() {
+  local line=${1-}
+  local key=${2-}
+  local part
+  IFS='|' read -r -a parts <<<"${line}"
+  for part in "${parts[@]}"; do
+    if [[ ${part} == "${key}="* ]]; then
+      printf '%s\n' "${part#*=}"
+      return 0
+    fi
+  done
+  return 1
+}
+
+storage_get() {
+  local uuid=${1-}
+  local line current
+  [[ -n ${uuid} ]] || return 1
+  while IFS= read -r line || [[ -n ${line} ]]; do
+    current=$(storage_parse "${line}" uuid || true)
+    if [[ ${current} == "${uuid}" ]]; then
+      printf '%s\n' "${line}"
+      return 0
+    fi
+  done < <(storage_list)
+  return 1
+}
+
+storage_delete() {
+  local uuid=${1-}
+  local db lock tmp found=0 line current
+  [[ -n ${uuid} ]] || return 1
+  storage_init
+  db=$(storage_db_path)
+  lock=$(storage_lock_path)
+  tmp="${db}.tmp.$$"
+
+  (
+    flock -x 9
+    : >"${tmp}"
+    while IFS= read -r line || [[ -n ${line} ]]; do
+      current=$(storage_parse "${line}" uuid || true)
+      if [[ ${current} == "${uuid}" ]]; then
+        found=1
+        continue
+      fi
+      printf '%s\n' "${line}" >>"${tmp}"
+    done <"${db}"
+
+    if (( found == 0 )); then
+      rm -f "${tmp}"
+      exit 1
+    fi
+
+    mv "${tmp}" "${db}"
+  ) 9>>"${lock}"
+}
+
+storage_count() {
+  local count=0 line
+  while IFS= read -r line || [[ -n ${line} ]]; do
+    [[ -n ${line} ]] || continue
+    ((count++))
+  done < <(storage_list)
+  printf '%s\n' "${count}"
+}