Merge pull request #178 from christianlouis/codex/m11-parser-compatibility

feat: add DMARC aggregate parser compatibility
This commit is contained in:
Christian Krakau-Louis
2026-05-23 14:04:04 +02:00
committed by GitHub
3 changed files with 368 additions and 55 deletions
+207 -53
View File
@@ -3,7 +3,7 @@ import io
import logging
import zipfile
from datetime import datetime
from typing import Any, Dict, Optional
from typing import Any, Dict, List, Optional
import defusedxml.ElementTree as ET
@@ -136,76 +136,231 @@ class DMARCParser:
for child in el:
DMARCParser._strip_namespace(child)
@staticmethod
def _namespace(tag: str) -> str:
"""Return the XML namespace from an ElementTree tag."""
return tag[1:].split("}", 1)[0] if tag.startswith("{") and "}" in tag else ""
@staticmethod
def _safe_int(value: Any, default: int = 0) -> int:
"""Parse integer fields without failing the entire report on bad optional data."""
try:
return int(value)
except (TypeError, ValueError):
return default
@staticmethod
def _text(parent, name: str, default: str = "") -> str:
"""Return stripped child text for a parsed XML element."""
return (parent.findtext(name, default) or default).strip()
@staticmethod
def _parse_text_list(parent, name: str) -> List[str]:
"""Return all non-empty child text values for repeated simple elements."""
return [
text
for text in (DMARCParser._text(child, ".") for child in parent.findall(name))
if text
]
@staticmethod
def _collect_extension_values(parent) -> Dict[str, Any]:
"""Capture namespaced extension values without coupling to vendor-specific schemas."""
values: Dict[str, Any] = {}
for child in list(parent):
key = child.tag
if len(child):
values[key] = DMARCParser._collect_extension_values(child)
else:
values[key] = (child.text or "").strip()
return values
@staticmethod
def _extension_value(element) -> Any:
"""Return a scalar or nested mapping for a vendor extension element."""
if len(element):
return DMARCParser._collect_extension_values(element)
return (element.text or "").strip()
@staticmethod
def _detect_variant(root, xml_namespace: str) -> dict:
"""Identify the aggregate report format variant for debugging/import history."""
version = DMARCParser._text(root, "version", "1.0")
has_rfc9990_fields = any(
root.find(path) is not None
for path in (
"report_metadata/generator",
"policy_published/discovery_method",
"policy_published/np",
"policy_published/testing",
"record/identifiers/envelope_to",
)
)
if xml_namespace or has_rfc9990_fields:
variant = "rfc9990"
else:
variant = "rfc7489-compatible"
return {
"variant": variant,
"schema_version": version,
"xml_namespace": xml_namespace,
}
@staticmethod
def _parse_metadata(root) -> dict:
"""Parse the report_metadata section of a DMARC XML report."""
report: dict = {}
metadata = root.find("report_metadata")
if metadata is not None:
report["report_id"] = metadata.findtext("report_id", "")
report["org_name"] = metadata.findtext("org_name", "")
report["email"] = metadata.findtext("email", "")
report["report_id"] = DMARCParser._text(metadata, "report_id")
report["org_name"] = DMARCParser._text(metadata, "org_name")
report["email"] = DMARCParser._text(metadata, "email")
report["extra_contact_info"] = DMARCParser._text(metadata, "extra_contact_info")
report["generator"] = DMARCParser._text(metadata, "generator")
errors = DMARCParser._parse_text_list(metadata, "error")
if errors:
report["errors"] = errors
date_range = metadata.find("date_range")
if date_range is not None:
begin_ts = int(date_range.findtext("begin", 0))
end_ts = int(date_range.findtext("end", 0))
begin_ts = DMARCParser._safe_int(date_range.findtext("begin", 0))
end_ts = DMARCParser._safe_int(date_range.findtext("end", 0))
report["begin_date"] = datetime.fromtimestamp(begin_ts).isoformat()
report["end_date"] = datetime.fromtimestamp(end_ts).isoformat()
report["begin_timestamp"] = begin_ts
report["end_timestamp"] = end_ts
return report
@staticmethod
def _parse_policy(root) -> dict:
"""Parse policy_published, including RFC 9990 optional fields."""
policy = root.find("policy_published")
if policy is None:
return {}
parsed = {
"domain": DMARCParser._text(policy, "domain"),
"policy": {
"p": DMARCParser._text(policy, "p", "none"),
"sp": DMARCParser._text(policy, "sp"),
"pct": DMARCParser._text(policy, "pct", "100"),
"np": DMARCParser._text(policy, "np"),
"fo": DMARCParser._text(policy, "fo"),
"adkim": DMARCParser._text(policy, "adkim"),
"aspf": DMARCParser._text(policy, "aspf"),
"testing": DMARCParser._text(policy, "testing"),
"discovery_method": DMARCParser._text(policy, "discovery_method"),
},
}
parsed["policy"] = {key: value for key, value in parsed["policy"].items() if value}
parsed["policy"].setdefault("pct", "100")
return parsed
@staticmethod
def _parse_policy_reasons(policy_evaluated) -> List[dict]:
"""Parse policy_evaluated/reason override data."""
reasons = []
for reason in policy_evaluated.findall("reason"):
parsed = {
"type": DMARCParser._text(reason, "type"),
"comment": DMARCParser._text(reason, "comment"),
}
if parsed["type"] or parsed["comment"]:
reasons.append(parsed)
return reasons
@staticmethod
def _parse_row(record_elem) -> dict:
"""Parse the record row and policy_evaluated section."""
parsed: dict = {}
row = record_elem.find("row")
if row is None:
return parsed
parsed["source_ip"] = DMARCParser._text(row, "source_ip")
parsed["count"] = DMARCParser._safe_int(row.findtext("count", 0))
policy_evaluated = row.find("policy_evaluated")
if policy_evaluated is None:
return parsed
parsed["disposition"] = DMARCParser._text(policy_evaluated, "disposition", "none")
parsed["dkim_result"] = DMARCParser._text(policy_evaluated, "dkim").lower()
parsed["spf_result"] = DMARCParser._text(policy_evaluated, "spf").lower()
reasons = DMARCParser._parse_policy_reasons(policy_evaluated)
if reasons:
parsed["policy_override_reasons"] = reasons
return parsed
@staticmethod
def _parse_identifiers(record_elem) -> dict:
"""Parse identifier fields used for aggregate policy evaluation."""
parsed: dict = {}
identifiers = record_elem.find("identifiers")
if identifiers is None:
return parsed
parsed["header_from"] = DMARCParser._text(identifiers, "header_from")
parsed["envelope_from"] = DMARCParser._text(identifiers, "envelope_from")
parsed["envelope_to"] = DMARCParser._text(identifiers, "envelope_to")
return parsed
@staticmethod
def _parse_auth_results(record_elem) -> dict:
"""Parse uninterpreted DKIM/SPF authentication results."""
parsed: dict = {}
auth_results = record_elem.find("auth_results")
if auth_results is None:
return parsed
spf_entries = [
{
"domain": DMARCParser._text(spf, "domain"),
"scope": DMARCParser._text(spf, "scope"),
"result": DMARCParser._text(spf, "result").lower(),
"human_result": DMARCParser._text(spf, "human_result"),
}
for spf in auth_results.findall("spf")
]
if spf_entries:
parsed["spf"] = spf_entries
dkim_entries = [
{
"domain": DMARCParser._text(dkim, "domain"),
"result": DMARCParser._text(dkim, "result").lower(),
"selector": DMARCParser._text(dkim, "selector"),
"human_result": DMARCParser._text(dkim, "human_result"),
}
for dkim in auth_results.findall("dkim")
]
if dkim_entries:
parsed["dkim"] = dkim_entries
return parsed
@staticmethod
def _parse_record_extensions(record_elem) -> dict:
"""Parse record-level extension elements."""
extension_values = {}
for child in record_elem:
if child.tag not in {"row", "identifiers", "auth_results"}:
extension_values[child.tag] = DMARCParser._extension_value(child)
return {"extensions": extension_values} if extension_values else {}
@staticmethod
def _parse_record(record_elem) -> dict:
"""Parse a single <record> element into a dictionary."""
record: dict = {}
row = record_elem.find("row")
if row is not None:
record["source_ip"] = row.findtext("source_ip", "")
record["count"] = int(row.findtext("count", 0))
policy_evaluated = row.find("policy_evaluated")
if policy_evaluated is not None:
record["disposition"] = policy_evaluated.findtext("disposition", "none")
record["dkim_result"] = policy_evaluated.findtext("dkim", "").lower()
record["spf_result"] = policy_evaluated.findtext("spf", "").lower()
identifiers = record_elem.find("identifiers")
if identifiers is not None:
record["header_from"] = identifiers.findtext("header_from", "")
auth_results = record_elem.find("auth_results")
if auth_results is not None:
spf_entries = [
{
"domain": spf.findtext("domain", ""),
"result": spf.findtext("result", "").lower(),
}
for spf in auth_results.findall("spf")
]
if spf_entries:
record["spf"] = spf_entries
dkim_entries = [
{
"domain": dkim.findtext("domain", ""),
"result": dkim.findtext("result", "").lower(),
"selector": dkim.findtext("selector", ""),
}
for dkim in auth_results.findall("dkim")
]
if dkim_entries:
record["dkim"] = dkim_entries
record.update(DMARCParser._parse_row(record_elem))
record.update(DMARCParser._parse_identifiers(record_elem))
record.update(DMARCParser._parse_auth_results(record_elem))
record.update(DMARCParser._parse_record_extensions(record_elem))
return record
@staticmethod
def _compute_summary(records: list) -> dict:
"""Compute aggregate pass/fail statistics for a list of records."""
total_count = sum(r["count"] for r in records)
total_count = sum(r.get("count", 0) for r in records)
passed_count = sum(
r["count"]
r.get("count", 0)
for r in records
if r.get("spf_result") == "pass" or r.get("dkim_result") == "pass"
)
@@ -224,19 +379,18 @@ class DMARCParser:
"""
try:
root = ET.fromstring(xml_content)
xml_namespace = DMARCParser._namespace(root.tag)
DMARCParser._strip_namespace(root)
report = DMARCParser._parse_metadata(root)
report.update(DMARCParser._detect_variant(root, xml_namespace))
# Parse policy published
policy = root.find("policy_published")
if policy is not None:
report["domain"] = policy.findtext("domain", "")
report["policy"] = {
"p": policy.findtext("p", "none"),
"sp": policy.findtext("sp", ""),
"pct": policy.findtext("pct", "100"),
}
report.update(DMARCParser._parse_policy(root))
extension = root.find("extension")
if extension is not None:
report["extensions"] = DMARCParser._collect_extension_values(extension)
# Parse records
records = [DMARCParser._parse_record(elem) for elem in root.findall("record")]
+156
View File
@@ -129,3 +129,159 @@ class TestDMARCParser:
assert result["domain"] == "example.com"
assert result["records"] == []
assert result["summary"]["total_count"] == 0
def test_parse_rfc9990_style_report_variant(self):
"""RFC 9990-era namespaces and optional fields should parse without breaking legacy shape."""
xml = b"""
<feedback xmlns="urn:ietf:params:xml:ns:dmarc-2.0"
xmlns:vendor="https://reports.example.test/dmarc">
<version>1.0</version>
<report_metadata>
<org_name>Example Receiver</org_name>
<email>dmarc@example.test</email>
<extra_contact_info>https://example.test/dmarc</extra_contact_info>
<report_id>2026-05-23-example.org</report_id>
<date_range>
<begin>1779494400</begin>
<end>1779580799</end>
</date_range>
<error>Multiple DMARC records were ignored before treewalk.</error>
<generator>ExampleRUA 2.0</generator>
</report_metadata>
<policy_published>
<domain>example.org</domain>
<discovery_method>treewalk</discovery_method>
<p>quarantine</p>
<sp>reject</sp>
<np>none</np>
<fo>1</fo>
<adkim>s</adkim>
<aspf>r</aspf>
<testing>y</testing>
</policy_published>
<extension>
<vendor:receiver>mx1.example.test</vendor:receiver>
</extension>
<record>
<row>
<source_ip>2001:db8::1</source_ip>
<count>5</count>
<policy_evaluated>
<disposition>quarantine</disposition>
<dkim>fail</dkim>
<spf>pass</spf>
<reason>
<type>local_policy</type>
<comment>trusted relay</comment>
</reason>
</policy_evaluated>
</row>
<identifiers>
<header_from>news.example.org</header_from>
<envelope_from>bounce.example.org</envelope_from>
<envelope_to>customer.example.net</envelope_to>
</identifiers>
<auth_results>
<dkim>
<domain>example.net</domain>
<selector>selector1</selector>
<result>fail</result>
<human_result>body hash did not verify</human_result>
</dkim>
<spf>
<domain>bounce.example.org</domain>
<scope>mfrom</scope>
<result>pass</result>
<human_result>sender authorized</human_result>
</spf>
</auth_results>
<vendor:source>mail-platform</vendor:source>
</record>
</feedback>
"""
result = DMARCParser.parse_file(xml, "report.xml")
assert result["variant"] == "rfc9990"
assert result["schema_version"] == "1.0"
assert result["xml_namespace"] == "urn:ietf:params:xml:ns:dmarc-2.0"
assert result["report_id"] == "2026-05-23-example.org"
assert result["generator"] == "ExampleRUA 2.0"
assert result["errors"] == ["Multiple DMARC records were ignored before treewalk."]
assert result["extensions"] == {"receiver": "mx1.example.test"}
assert result["policy"] == {
"p": "quarantine",
"sp": "reject",
"pct": "100",
"np": "none",
"fo": "1",
"adkim": "s",
"aspf": "r",
"testing": "y",
"discovery_method": "treewalk",
}
record = result["records"][0]
assert record["source_ip"] == "2001:db8::1"
assert record["count"] == 5
assert record["envelope_from"] == "bounce.example.org"
assert record["envelope_to"] == "customer.example.net"
assert record["policy_override_reasons"] == [
{"type": "local_policy", "comment": "trusted relay"}
]
assert record["dkim"] == [
{
"domain": "example.net",
"result": "fail",
"selector": "selector1",
"human_result": "body hash did not verify",
}
]
assert record["spf"] == [
{
"domain": "bounce.example.org",
"scope": "mfrom",
"result": "pass",
"human_result": "sender authorized",
}
]
assert record["extensions"] == {"source": "mail-platform"}
assert result["summary"]["total_count"] == 5
assert result["summary"]["passed_count"] == 5
def test_parse_report_with_bad_optional_numbers_uses_safe_defaults(self):
"""Real reports with malformed counts or timestamps should not crash parsing."""
xml = b"""
<feedback>
<report_metadata>
<org_name>Example Receiver</org_name>
<email>dmarc@example.test</email>
<report_id>bad-numbers</report_id>
<date_range>
<begin>not-a-timestamp</begin>
<end>also-bad</end>
</date_range>
</report_metadata>
<policy_published>
<domain>example.com</domain>
<p>none</p>
</policy_published>
<record>
<row>
<source_ip>203.0.113.10</source_ip>
<count>not-a-count</count>
<policy_evaluated>
<disposition>none</disposition>
<dkim>pass</dkim>
<spf>pass</spf>
</policy_evaluated>
</row>
</record>
</feedback>
"""
result = DMARCParser.parse_file(xml, "report.xml")
assert result["begin_timestamp"] == 0
assert result["end_timestamp"] == 0
assert result["records"][0]["count"] == 0
assert result["summary"]["total_count"] == 0
+5 -2
View File
@@ -182,12 +182,15 @@ Exit criteria:
## Milestone 11: DMARC Format Compatibility (DMARCbis) and Standards Alignment
Status: Planned
Status: In Progress
Goal: keep DMARQ compatible with evolving DMARC report formats and nomenclature without breaking existing imports.
Delivered:
- Add parser compatibility for RFC 9990-style aggregate report namespaces, version detection, policy metadata, identifiers, override reasons, auth-result details, and namespaced extensions.
- Keep legacy RFC 7489-style reports backward compatible through fixture coverage.
Planned:
- Add parser compatibility for newer aggregate report schemas/namespaces.
- Store newly introduced fields with safe defaults.
- Update CSV export and domain/source reporting to include new metadata where it improves operator actionability.
- Add fixture-driven tests for representative real-world DMARCbis-style reports.