Color metadata embed orange when report has parse errors

README.md

@@ -0,0 +1,67 @@
+# dmarc-to-discord
+
+A tiny HTTP relay that turns [parsedmarc](https://github.com/domainaware/parsedmarc) aggregate-report webhooks into nicely formatted Discord embeds.
+
+parsedmarc parses DMARC aggregate reports from your inbox and POSTs each one as JSON to a webhook URL of your choosing. This service is that webhook: it listens for parsedmarc's POSTs, builds one metadata embed plus one embed per record (source IP, alignment, disposition, auth results, override reasons), and forwards them to a Discord channel.
+
+## How it looks
+
+Each report produces:
+
+- **1 metadata embed** — reporter, report ID, timespan, published policy (`p`, `sp`, `adkim`, `aspf`, `pct`, `fo`), and a pass/total summary.
+- **1 embed per record** — source IP/country/rDNS/ASN, message count, disposition, header-from, DMARC/SPF/DKIM alignment, policy-evaluated SPF/DKIM, raw auth results, and any policy override reasons.
+
+Embeds are colored green (DMARC aligned), red (quarantine/reject), or orange (anything else). Discord allows max 10 embeds per message, so larger reports are split across multiple messages.
+
+## Configuration
+
+Environment variables:
+
+| Variable | Default | Description |
+| --- | --- | --- |
+| `DISCORD_WEBHOOK_URL` | *(required)* | Discord channel webhook URL |
+| `LISTEN_HOST` | `127.0.0.1` | bind address |
+| `LISTEN_PORT` | `8080` | bind port |
+
+## Running
+
+Requires Python 3.9+ and `requests`.
+
+```sh
+pip install requests
+DISCORD_WEBHOOK_URL=https://discord.com/api/webhooks/... ./dmarc_to_discord.py
+```
+
+`GET /`, `/health`, and `/healthz` return `200 ok` for liveness checks.
+
+## Wiring up parsedmarc
+
+In `parsedmarc.ini`:
+
+```ini
+[webhook]
+aggregate_url = http://127.0.0.1:8080/
+```
+
+(parsedmarc also supports `forensic_url` and `smtp_tls_url`; this relay currently only handles the aggregate-report schema.)
+
+## Running as a systemd service
+
+A unit file is included. It expects the script at `/usr/local/bin/dmarc_to_discord.py` and the webhook URL in `/etc/dmarc-to-discord.env`:
+
+```sh
+sudo install -m 0755 dmarc_to_discord.py /usr/local/bin/
+sudo install -m 0644 dmarc-to-discord.service /etc/systemd/system/
+echo 'DISCORD_WEBHOOK_URL=https://discord.com/api/webhooks/...' | sudo tee /etc/dmarc-to-discord.env
+sudo chmod 0600 /etc/dmarc-to-discord.env
+sudo systemctl daemon-reload
+sudo systemctl enable --now dmarc-to-discord.service
+```
+
+The unit runs under `DynamicUser=` with the filesystem locked down (`ProtectSystem=strict`, `ProtectHome=true`, no kernel/cgroup access, network restricted to `AF_INET`/`AF_INET6`) and is ordered `Before=parsedmarc.service` so parsedmarc's first POSTs aren't refused.
+
+## Notes
+
+- The server speaks plain HTTP. Bind to `127.0.0.1` (the default) and run parsedmarc on the same host, or terminate TLS in front of it.
+- Discord 429s are honored via `retry_after`; there's a 0.5 s gap between messages to stay friendly to the rate limiter.
+- No persistence — if Discord is down when a report arrives, the report is dropped (parsedmarc will not retry).

dmarc_to_discord.py

@@ -38,19 +38,23 @@ def truncate(s: str, n: int = MAX_FIELD_VALUE_LEN) -> str:
     return s if len(s) <= n else s[: n - 3] + "..."
 
 
-def result_icon(r): return {"pass": "✅", "fail": "❌", "softfail": "⚠️",
-                            "neutral": "➖", "temperror": "⚠️", "permerror": "⚠️"}.get(r or "", "❓")
+def result_icon(r): return {"pass": "✅", "fail": "❌", "softfail": "⚠️", "neutral": "➖",
+                            "none": "➖", "temperror": "⚠️", "permerror": "⚠️"}.get(r or "", "❓")
 
 
-def bool_icon(b): return "✅" if b else "❌"
+def bool_icon(b): return "✅" if b is True else "❌" if b is False else "❔"
 
 
 def record_color(record):
-    if record.get("alignment", {}).get("dmarc"):
+    # Drive color by DMARC alignment, not by disposition: on a p=none policy every
+    # failure has disposition=none, and we don't want real spoofing to look the same
+    # as benign forwarder noise.
+    dmarc = (record.get("alignment") or {}).get("dmarc")
+    if dmarc is True:
         return COLOR_PASS
-    if record.get("policy_evaluated", {}).get("disposition") in ("quarantine", "reject"):
+    if dmarc is False:
         return COLOR_FAIL
-    return COLOR_PARTIAL
+    return COLOR_PARTIAL  # alignment missing → unknown
 
 
 def build_metadata_embed(report):
@@ -60,9 +64,13 @@ def build_metadata_embed(report):
     total = sum(r.get("count", 0) for r in records)
     passing = sum(r.get("count", 0) for r in records if r.get("alignment", {}).get("dmarc"))
 
+    reporter_lines = [meta.get("org_name", "unknown"), meta.get("org_email", "")]
+    if extra := meta.get("org_extra_contact_info"):
+        reporter_lines.append(extra)
+
     fields = [
         {"name": "Reporter",
-         "value": f"{meta.get('org_name', 'unknown')}\n{meta.get('org_email', '')}", "inline": True},
+         "value": "\n".join(filter(None, reporter_lines)), "inline": True},
         {"name": "Report ID", "value": f"`{meta.get('report_id', 'unknown')}`", "inline": True},
         {"name": "Timespan (UTC)",
          "value": f"{meta.get('begin_date', '?')} →\n{meta.get('end_date', '?')}", "inline": False},
@@ -70,33 +78,97 @@ def build_metadata_embed(report):
          "value": (f"**Domain:** `{policy.get('domain', '?')}`\n"
                    f"**p / sp:** `{policy.get('p', '?')}` / `{policy.get('sp', '?')}`\n"
                    f"**adkim / aspf:** `{policy.get('adkim', '?')}` / `{policy.get('aspf', '?')}`\n"
-                   f"**pct:** `{policy.get('pct', '?')}`  •  **fo:** `{policy.get('fo', '?')}`"),
+                   f"**pct:** `{policy.get('pct') or '100'}`  •  **fo:** `{policy.get('fo', '?')}`"),
          "inline": False},
         {"name": "Summary",
          "value": f"**Records:** {len(records)}\n**Messages:** {total}\n**DMARC pass:** {passing} / {total}",
          "inline": False},
     ]
-    if errors := (meta.get("errors") or []):
+    errors = meta.get("errors") or []
+    if errors:
         fields.append({"name": "Errors",
                        "value": truncate("\n".join(f"• {e}" for e in errors)), "inline": False})
     return {"title": f"DMARC Aggregate Report — {policy.get('domain', 'unknown')}",
-            "color": COLOR_INFO, "fields": fields}
+            "color": COLOR_PARTIAL if errors else COLOR_INFO, "fields": fields}
 
 
-def build_record_embed(record, idx, total):
+def diagnose_record(record):
+    """One-line explanation of why DMARC passed or failed for this record."""
+    align = record.get("alignment") or {}
+    auth = record.get("auth_results") or {}
+    ids = record.get("identifiers") or {}
+    header_from = ids.get("header_from") or "?"
+    spf_results = auth.get("spf") or []
+    dkim_results = auth.get("dkim") or []
+
+    dmarc = align.get("dmarc")
+    if dmarc is None:
+        return None  # parsedmarc didn't supply alignment; don't fabricate a verdict
+
+    if dmarc:
+        via = [name for name, ok in (("SPF", align.get("spf")), ("DKIM", align.get("dkim"))) if ok]
+        return "✅ **DMARC pass** — aligned via " + (" + ".join(via) if via else "?")
+
+    parts = []
+    spf_pass = next((r for r in spf_results if (r.get("result") or "").lower() == "pass"), None)
+    if not spf_results:
+        parts.append("SPF not evaluated")
+    elif spf_pass:
+        parts.append(f"SPF passed on `{spf_pass.get('domain', '?')}` (not aligned with `{header_from}`)")
+    else:
+        worst = spf_results[0]
+        parts.append(f"SPF `{worst.get('result', '?')}` on `{worst.get('domain', '?')}`")
+
+    dkim_pass = next((r for r in dkim_results if (r.get("result") or "").lower() == "pass"), None)
+    if not dkim_results:
+        parts.append("DKIM not signed")
+    elif dkim_pass:
+        parts.append(f"DKIM passed on `{dkim_pass.get('domain', '?')}` (not aligned with `{header_from}`)")
+    else:
+        failed = ", ".join(f"`{r.get('domain', '?')}`/`{r.get('selector', '?')}`→`{r.get('result', '?')}`"
+                           for r in dkim_results)
+        parts.append(f"DKIM failed ({failed})")
+
+    return "❌ **DMARC fail** — " + "; ".join(parts)
+
+
+def build_record_embed(record, idx, total, policy_domain=None):
     src, align = record.get("source", {}), record.get("alignment", {})
     pol, ids, auth = record.get("policy_evaluated", {}), record.get("identifiers", {}), record.get("auth_results", {})
     rdns = src.get("reverse_dns") or "—"
     asn = src.get("asn")
     as_str = f"AS{asn} ({src.get('as_name', '?')})" if asn else "—"
+    if asn and (as_domain := src.get("as_domain")):
+        as_str += f" — `{as_domain}`"
+
+    sender_bits = []
+    if name := src.get("name"):
+        sender_bits.append(f"**{name}**")
+    if base := src.get("base_domain"):
+        sender_bits.append(f"`{base}`")
+    sender_line = " ".join(sender_bits) + "\n" if sender_bits else ""
+
+    header_from = ids.get("header_from") or "?"
+    hf_note = ""
+    if policy_domain and header_from != "?" and header_from.lower() != policy_domain.lower():
+        hf_note = "  *(subdomain — `sp` applies)*"
+    from_lines = [f"**Header From:** `{header_from}`{hf_note}",
+                  f"**Envelope From:** `{ids.get('envelope_from') or '—'}`"]
+    if env_to := ids.get("envelope_to"):
+        from_lines.append(f"**Envelope To:** `{env_to}`")
 
     fields = [
         {"name": "Source",
-         "value": f"**IP:** `{src.get('ip_address', '?')}` ({src.get('country', '??')})\n"
+         "value": sender_line +
+                  f"**IP:** `{src.get('ip_address', '?')}` ({src.get('country', '??')})\n"
                   f"**rDNS:** `{rdns}`\n**ASN:** {as_str}", "inline": False},
+    ]
+    if verdict := diagnose_record(record):
+        fields.append({"name": "Verdict", "value": truncate(verdict), "inline": False})
+    fields += [
         {"name": "Messages", "value": f"**{record.get('count', 0)}**", "inline": True},
         {"name": "Disposition", "value": f"`{pol.get('disposition', '?')}`", "inline": True},
-        {"name": "Header From", "value": f"`{ids.get('header_from', '?')}`", "inline": True},
+        {"name": "Identifiers", "value": "\n".join(from_lines), "inline": False},
         {"name": "Alignment",
          "value": f"{bool_icon(align.get('dmarc'))} DMARC\n"
                   f"{bool_icon(align.get('spf'))} SPF\n"
@@ -124,8 +196,9 @@ def build_record_embed(record, idx, total):
 def send_to_discord(report):
     embeds = [build_metadata_embed(report)]
     records = report.get("records", [])
+    policy_domain = (report.get("policy_published") or {}).get("domain")
     for i, rec in enumerate(records, start=1):
-        embeds.append(build_record_embed(rec, i, len(records)))
+        embeds.append(build_record_embed(rec, i, len(records), policy_domain))
 
     for i in range(0, len(embeds), MAX_EMBEDS_PER_MESSAGE):
         payload = {"embeds": embeds[i: i + MAX_EMBEDS_PER_MESSAGE], "username": "parsedmarc"}