From 1afc95fe8b20254c7b9e6eac8d3eb09aab1109b6 Mon Sep 17 00:00:00 2001
From: "Adrian A. Baumann" <ade@adebaumann.com>
Date: Sat, 28 Feb 2026 20:02:48 +0100
Subject: [PATCH] feat: add ShorewallGenerator (zones, interfaces, policy,
 rules, masq, json, zip)

---
 backend/app/shorewall_generator.py | 74 ++++++++++++++++++++++++++++++
 1 file changed, 74 insertions(+)
 create mode 100644 backend/app/shorewall_generator.py

diff --git a/backend/app/shorewall_generator.py b/backend/app/shorewall_generator.py
new file mode 100644
index 0000000..5c1a81c
--- /dev/null
+++ b/backend/app/shorewall_generator.py
@@ -0,0 +1,74 @@
+import io
+import zipfile
+from datetime import datetime, timezone
+from app import models
+
+
+class ShorewallGenerator:
+    def __init__(self, config: models.Config) -> None:
+        self._config = config
+        self._ts = datetime.now(timezone.utc).strftime("%Y-%m-%dT%H:%M:%SZ")
+
+    def _header(self, filename: str) -> str:
+        return (
+            f"# {filename} — generated by shorefront "
+            f"| config: {self._config.name} "
+            f"| {self._ts}\n"
+        )
+
+    def _col(self, *values: str, width: int = 16) -> str:
+        return "".join(v.ljust(width) for v in values).rstrip() + "\n"
+
+    def zones(self) -> str:
+        lines = [self._header("zones"), "#ZONE".ljust(16) + "TYPE".ljust(16) + "OPTIONS\n"]
+        for z in self._config.zones:
+            lines.append(self._col(z.name, z.type, z.options or "-"))
+        return "".join(lines)
+
+    def interfaces(self) -> str:
+        lines = [self._header("interfaces"), "#ZONE".ljust(16) + "INTERFACE".ljust(16) + "OPTIONS\n"]
+        for iface in self._config.interfaces:
+            lines.append(self._col(iface.zone.name, iface.name, iface.options or "-"))
+        return "".join(lines)
+
+    def policy(self) -> str:
+        lines = [self._header("policy"), "#SOURCE".ljust(16) + "DEST".ljust(16) + "POLICY".ljust(16) + "LOG LEVEL\n"]
+        for p in sorted(self._config.policies, key=lambda x: x.position):
+            lines.append(self._col(p.src_zone.name, p.dst_zone.name, p.policy, p.log_level or "-"))
+        return "".join(lines)
+
+    def rules(self) -> str:
+        lines = [
+            self._header("rules"),
+            "#ACTION".ljust(16) + "SOURCE".ljust(24) + "DEST".ljust(24) + "PROTO".ljust(10) + "DPORT".ljust(10) + "SPORT\n",
+        ]
+        for r in sorted(self._config.rules, key=lambda x: x.position):
+            src = (r.src_zone.name if r.src_zone else "all") + (f":{r.src_ip}" if r.src_ip else "")
+            dst = (r.dst_zone.name if r.dst_zone else "all") + (f":{r.dst_ip}" if r.dst_ip else "")
+            lines.append(self._col(r.action, src, dst, r.proto or "-", r.dport or "-", r.sport or "-", width=16))
+        return "".join(lines)
+
+    def masq(self) -> str:
+        lines = [self._header("masq"), "#INTERFACE".ljust(24) + "SOURCE".ljust(24) + "ADDRESS\n"]
+        for m in self._config.masq_entries:
+            lines.append(self._col(m.out_interface, m.source_network, m.to_address or "-", width=24))
+        return "".join(lines)
+
+    def as_json(self) -> dict:
+        return {
+            "zones": self.zones(),
+            "interfaces": self.interfaces(),
+            "policy": self.policy(),
+            "rules": self.rules(),
+            "masq": self.masq(),
+        }
+
+    def as_zip(self) -> bytes:
+        buf = io.BytesIO()
+        with zipfile.ZipFile(buf, "w", zipfile.ZIP_DEFLATED) as zf:
+            zf.writestr("zones", self.zones())
+            zf.writestr("interfaces", self.interfaces())
+            zf.writestr("policy", self.policy())
+            zf.writestr("rules", self.rules())
+            zf.writestr("masq", self.masq())
+        return buf.getvalue()