feat: add guarded Dynadot DNS reconciliation

ampg/dns.py

@@ -14,7 +14,7 @@ from .addresses import effective_address_records
 
 
 DNS_MODES = ("static", "dynamic")
-DNS_PROVIDERS = ("namecheap",)
+DNS_PROVIDERS = ("namecheap", "dynadot")
 DNS_MAIL_POLICIES = ("preserve", "disabled")
 DEFAULT_TTL = 1800
 NAMECHEAP_SUPPORTED_RECORD_TYPES = {
@@ -91,6 +91,7 @@ class ProviderDNSRecord:
     value: str
     ttl: int = DEFAULT_TTL
     mx_pref: int | None = None
+    provider_value2: str | None = None
 
 
 @dataclass(frozen=True)
@@ -113,6 +114,7 @@ class DNSZoneSnapshot:
     records: tuple[ProviderDNSRecord, ...]
     status: str
     message: str
+    zone_ttl: int | None = None
 
 
 @dataclass(frozen=True)
@@ -776,7 +778,13 @@ def _default_backup_dir(config: GatewayConfig) -> Path:
 
 def _backup_domain(provider, domain: str, backup_dir: Path) -> DNSBackupResult:
     snapshot = provider.get_hosts(domain)
-    path = _write_dns_backup(provider.name, domain, snapshot.raw, backup_dir)
+    path = _write_dns_backup(
+        provider.name,
+        domain,
+        snapshot.raw,
+        backup_dir,
+        extension=getattr(provider, "backup_format", "txt"),
+    )
     return DNSBackupResult(
         provider=provider.name,
         domain=domain,
@@ -787,9 +795,16 @@ def _backup_domain(provider, domain: str, backup_dir: Path) -> DNSBackupResult:
     )
 
 
-def _write_dns_backup(provider: str, domain: str, raw: str, backup_dir: Path) -> Path:
+def _write_dns_backup(
+    provider: str,
+    domain: str,
+    raw: str,
+    backup_dir: Path,
+    *,
+    extension: str = "xml",
+) -> Path:
     stamp = _datetime.datetime.now(_datetime.UTC).strftime("%Y%m%d_%H%M%S")
-    path = backup_dir / provider / f"{domain}.{stamp}.xml"
+    path = backup_dir / provider / f"{domain}.{stamp}.{extension}"
     path.parent.mkdir(parents=True, exist_ok=True)
     path.write_text(raw, encoding="utf-8")
     return path
@@ -799,9 +814,15 @@ def _records_supported_by_provider(
     provider: str,
     records: tuple[ProviderDNSRecord, ...] | list[ProviderDNSRecord],
 ) -> tuple[ProviderDNSRecord, ...]:
-    if provider != "namecheap":
+    if provider == "namecheap":
+        supported = NAMECHEAP_SUPPORTED_RECORD_TYPES
+    elif provider == "dynadot":
+        from .dynadot_dns import DYNADOT_SUPPORTED_RECORD_TYPES
+
+        supported = DYNADOT_SUPPORTED_RECORD_TYPES
+    else:
         return tuple(records)
-    return tuple(record for record in records if record.type in NAMECHEAP_SUPPORTED_RECORD_TYPES)
+    return tuple(record for record in records if record.type in supported)
 
 
 def _unsupported_record_changes(
@@ -809,11 +830,17 @@ def _unsupported_record_changes(
     provider: str,
     desired: tuple[ProviderDNSRecord, ...],
 ) -> tuple[DNSApplyChange, ...]:
-    if provider != "namecheap":
+    if provider == "namecheap":
+        supported = NAMECHEAP_SUPPORTED_RECORD_TYPES
+    elif provider == "dynadot":
+        from .dynadot_dns import DYNADOT_SUPPORTED_RECORD_TYPES
+
+        supported = DYNADOT_SUPPORTED_RECORD_TYPES
+    else:
         return ()
     changes = []
     for record in desired:
-        if record.type in NAMECHEAP_SUPPORTED_RECORD_TYPES:
+        if record.type in supported:
             continue
         changes.append(
             DNSApplyChange(
@@ -915,6 +942,7 @@ def _normalize_provider_record(record: ProviderDNSRecord) -> ProviderDNSRecord:
         value=record.value.strip(),
         ttl=int(record.ttl or DEFAULT_TTL),
         mx_pref=record.mx_pref,
+        provider_value2=record.provider_value2,
     )
 
 
@@ -946,11 +974,16 @@ def _url_host(value: str) -> str:
 def _dns_provider(provider: str, *, credentials: Path, client_ip: str | None):
     if provider == "namecheap":
         return NamecheapDNSProvider(credentials=credentials, client_ip=client_ip)
+    if provider == "dynadot":
+        from .dynadot_dns import DynadotDNSProvider
+
+        return DynadotDNSProvider(credentials=credentials)
     raise ValueError(f"unsupported DNS provider {provider!r}")
 
 
 class NamecheapDNSProvider:
     name = "namecheap"
+    backup_format = "xml"
 
     def __init__(self, *, credentials: Path, client_ip: str | None = None):
         self.credentials = credentials
@@ -1015,6 +1048,8 @@ class NamecheapDNSProvider:
         *,
         mail_policy: str,
     ) -> None:
+        if any(record.provider_value2 is not None for record in records):
+            raise ValueError("Namecheap records cannot set provider_value2")
         params = self._domain_params(domain)
         if mail_policy == "disabled":
             params["EmailType"] = "MX"

ampg/dns_manifest.py

@@ -21,6 +21,16 @@ from .dns import (
     NamecheapDNSProvider,
     ProviderDNSRecord,
 )
+from .dynadot_dns import (
+    DYNADOT_SUPPORTED_RECORD_TYPES,
+    DynadotDNSProvider,
+)
+
+
+_PROVIDER_RECORD_TYPES = {
+    "namecheap": NAMECHEAP_SUPPORTED_RECORD_TYPES,
+    "dynadot": DYNADOT_SUPPORTED_RECORD_TYPES,
+}
 
 
 _HOSTNAME = re.compile(
@@ -77,6 +87,7 @@ def _record_identity(record: ProviderDNSRecord) -> tuple[Any, ...]:
         record.value.strip(),
         int(record.ttl),
         record.mx_pref,
+        record.provider_value2,
     )
 
 
@@ -89,13 +100,14 @@ def _record_sort_key(record: ProviderDNSRecord) -> tuple[str, str, str, int]:
     )
 
 
-def _load_record(raw: Any) -> ManagedDNSRecord:
+def _load_record(raw: Any, provider: str) -> ManagedDNSRecord:
     if not isinstance(raw, dict):
         raise ValueError("managed DNS records must be objects")
     name = _record_name(_required_string(raw, "name"))
     record_type = _required_string(raw, "type").upper()
-    if record_type not in NAMECHEAP_SUPPORTED_RECORD_TYPES:
+    supported_types = _PROVIDER_RECORD_TYPES[provider]
-        raise ValueError(f"unsupported Namecheap record type: {record_type}")
+    if record_type not in supported_types:
+        raise ValueError(f"unsupported {provider} record type: {record_type}")
     value = _required_string(raw, "value")
     if (
         "\n" in value
@@ -114,6 +126,16 @@ def _load_record(raw: Any) -> ManagedDNSRecord:
             raise ValueError(f"record {name}/MX requires mx_pref")
     elif mx_pref is not None:
         raise ValueError(f"record {name}/{record_type} cannot set mx_pref")
+    provider_value2 = raw.get("provider_value2")
+    if provider_value2 is not None:
+        if provider != "dynadot" or record_type == "MX":
+            raise ValueError(
+                f"record {name}/{record_type} cannot set provider_value2"
+            )
+        if not isinstance(provider_value2, str) or not provider_value2:
+            raise ValueError(
+                f"record {name}/{record_type} has invalid provider_value2"
+            )
 
     replace = raw.get("replace", "all")
     if replace not in {"all", "value_prefix"}:
@@ -136,11 +158,13 @@ def _load_record(raw: Any) -> ManagedDNSRecord:
     ):
         raise ValueError(f"record {name}/{record_type} has invalid conflicts")
     conflict_types = tuple(item.upper() for item in raw_conflicts)
-    if any(item not in NAMECHEAP_SUPPORTED_RECORD_TYPES for item in conflict_types):
+    if any(item not in supported_types for item in conflict_types):
         raise ValueError(f"record {name}/{record_type} has unsupported conflicts")
 
     return ManagedDNSRecord(
-        record=ProviderDNSRecord(name, record_type, value, ttl, mx_pref),
+        record=ProviderDNSRecord(
+            name, record_type, value, ttl, mx_pref, provider_value2
+        ),
         replace=replace,
         match_value_prefix=match_value_prefix,
         conflict_types=conflict_types,
@@ -163,8 +187,8 @@ def load_dns_manifest(path: Path) -> DNSManifest:
     if not _HOSTNAME.fullmatch(zone):
         raise ValueError("zone must be a DNS hostname")
     provider = _required_string(document, "provider")
-    if provider != "namecheap":
+    if provider not in _PROVIDER_RECORD_TYPES:
-        raise ValueError("contract version 1 supports only Namecheap")
+        raise ValueError("contract version 1 has an unsupported DNS provider")
     if document.get("preserve_unmanaged") is not True:
         raise ValueError("preserve_unmanaged must be true")
     raw_protected = document.get("protected_names", [])
@@ -179,7 +203,7 @@ def load_dns_manifest(path: Path) -> DNSManifest:
         raise ValueError("records must be a non-empty list")
     if len(raw_records) > 100:
         raise ValueError("DNS manifest has too many managed records")
-    records = tuple(_load_record(raw) for raw in raw_records)
+    records = tuple(_load_record(raw, provider) for raw in raw_records)
     for managed in records:
         if _record_name(managed.record.name) in protected_names:
             raise ValueError(
@@ -241,8 +265,8 @@ def _changes(
     before_set = {_record_identity(record) for record in before}
     after_set = {_record_identity(record) for record in after}
     changes: list[dict[str, Any]] = []
-    for identity in sorted(before_set - after_set):
+    for identity in sorted(before_set - after_set, key=repr):
-        name, record_type, value, ttl, mx_pref = identity
+        name, record_type, value, ttl, mx_pref, provider_value2 = identity
         changes.append(
             {
                 "action": "remove",
@@ -251,10 +275,11 @@ def _changes(
                 "value": value,
                 "ttl": ttl,
                 "mx_pref": mx_pref,
+                "provider_value2": provider_value2,
             }
         )
-    for identity in sorted(after_set - before_set):
+    for identity in sorted(after_set - before_set, key=repr):
-        name, record_type, value, ttl, mx_pref = identity
+        name, record_type, value, ttl, mx_pref, provider_value2 = identity
         changes.append(
             {
                 "action": "add",
@@ -263,6 +288,7 @@ def _changes(
                 "value": value,
                 "ttl": ttl,
                 "mx_pref": mx_pref,
+                "provider_value2": provider_value2,
             }
         )
     return changes
@@ -273,6 +299,7 @@ def offline_plan(manifest: DNSManifest) -> dict[str, Any]:
         "contract_version": 1,
         "app_id": manifest.app_id,
         "zone": manifest.zone,
+        "provider": manifest.provider,
         "mode": "offline-plan",
         "preserve_unmanaged": True,
         "protected_names": list(manifest.protected_names),
@@ -283,6 +310,7 @@ def offline_plan(manifest: DNSManifest) -> dict[str, Any]:
                 "value": entry.record.value,
                 "ttl": entry.record.ttl,
                 "mx_pref": entry.record.mx_pref,
+                "provider_value2": entry.record.provider_value2,
                 "replace": entry.replace,
             }
             for entry in manifest.records
@@ -290,9 +318,15 @@ def offline_plan(manifest: DNSManifest) -> dict[str, Any]:
     }
 
 
-def _write_backup(zone: str, raw: str, backup_dir: Path) -> Path:
+def _write_backup(
+    provider: str,
+    zone: str,
+    raw: str,
+    backup_dir: Path,
+    extension: str,
+) -> Path:
     stamp = datetime.datetime.now(datetime.UTC).strftime("%Y%m%d_%H%M%S_%f")
-    path = backup_dir / "namecheap" / f"{zone}.{stamp}.xml"
+    path = backup_dir / provider / f"{zone}.{stamp}.{extension}"
     path.parent.mkdir(mode=0o700, parents=True, exist_ok=True)
     with path.open("x", encoding="utf-8") as backup:
         backup.write(raw)
@@ -307,11 +341,21 @@ def reconcile_dns_manifest(
     apply: bool = False,
     backup_dir: Path | None = None,
 ) -> dict[str, Any]:
+    if getattr(provider, "name", None) != manifest.provider:
+        raise DNSManifestError("provider credentials do not match the manifest")
     snapshot = provider.get_hosts(manifest.zone)
     if snapshot.status != "ok":
         raise DNSManifestError(
             f"provider fetch failed for {manifest.zone}: {snapshot.message}"
         )
+    if manifest.provider == "dynadot":
+        if snapshot.zone_ttl is None:
+            raise DNSManifestError("Dynadot did not return the observed zone TTL")
+        desired_ttls = {entry.record.ttl for entry in manifest.records}
+        if desired_ttls != {snapshot.zone_ttl}:
+            raise DNSManifestError(
+                "Dynadot manifest TTL must equal the observed zone-wide TTL"
+            )
     next_records = merge_dns_manifest_records(
         snapshot.records, manifest.records
     )
@@ -320,7 +364,14 @@ def reconcile_dns_manifest(
     if apply and changes:
         if backup_dir is None or not backup_dir.is_absolute():
             raise DNSManifestError("live apply requires an absolute backup_dir")
-        backup_path = _write_backup(manifest.zone, snapshot.raw, backup_dir)
+        extension = getattr(provider, "backup_format", "txt")
+        backup_path = _write_backup(
+            manifest.provider,
+            manifest.zone,
+            snapshot.raw,
+            backup_dir,
+            extension,
+        )
         provider.set_hosts(
             manifest.zone, next_records, mail_policy="preserve"
         )
@@ -340,6 +391,7 @@ def reconcile_dns_manifest(
         "contract_version": 1,
         "app_id": manifest.app_id,
         "zone": manifest.zone,
+        "provider": manifest.provider,
         "mode": "apply" if apply else "connected-plan",
         "status": (
             "applied"
@@ -360,3 +412,17 @@ def namecheap_provider(
     return NamecheapDNSProvider(
         credentials=credentials, client_ip=client_ip
     )
+
+
+def provider_from_credentials(
+    provider: str,
+    credentials: Path,
+    client_ip: str | None,
+) -> NamecheapDNSProvider | DynadotDNSProvider:
+    if provider == "namecheap":
+        return namecheap_provider(credentials, client_ip)
+    if provider == "dynadot":
+        if client_ip is not None:
+            raise ValueError("--client-ip is only valid for Namecheap")
+        return DynadotDNSProvider(credentials=credentials)
+    raise ValueError("unsupported DNS provider")

ampg/dns_manifest_cli.py

@@ -10,8 +10,8 @@ import sys
 from .dns_manifest import (
     DNSManifestError,
     load_dns_manifest,
-    namecheap_provider,
     offline_plan,
+    provider_from_credentials,
     reconcile_dns_manifest,
 )
 
@@ -27,7 +27,7 @@ def _parser() -> argparse.ArgumentParser:
     parser.add_argument(
         "--credentials",
         type=Path,
-        help="Namecheap key-value credential file; required for provider access",
+        help="Provider key-value credential file; required for provider access",
     )
     parser.add_argument("--client-ip")
     parser.add_argument(
@@ -60,8 +60,8 @@ def main(arguments: list[str] | None = None) -> int:
                 raise ValueError("--apply-zone must exactly match manifest zone")
             if apply and options.backup_dir is None:
                 raise ValueError("--backup-dir is required for live apply")
-            provider = namecheap_provider(
+            provider = provider_from_credentials(
-                options.credentials, options.client_ip
+                manifest.provider, options.credentials, options.client_ip
             )
             result = reconcile_dns_manifest(
                 manifest,
@@ -72,7 +72,7 @@ def main(arguments: list[str] | None = None) -> int:
         json.dump(result, sys.stdout, indent=2, sort_keys=True)
         sys.stdout.write("\n")
         return 0
-    except (DNSManifestError, OSError, ValueError) as error:
+    except (DNSManifestError, OSError, RuntimeError, ValueError) as error:
         print(f"ampg-dns-manifest: {error}", file=sys.stderr)
         return 1
 

ampg/dynadot_dns.py

@@ -0,0 +1,316 @@
+"""Guarded Dynadot REST v2 DNS provider.
+
+Dynadot updates replace the full zone and use one zone-wide TTL.  The provider
+therefore models every documented record field and rejects lossy or mixed-TTL
+writes.  Credentials are sent only in signed headers, never in URLs or output.
+"""
+
+from __future__ import annotations
+
+import base64
+import hashlib
+import hmac
+import ipaddress
+import json
+from pathlib import Path
+import urllib.error
+import urllib.parse
+import urllib.request
+import uuid
+from typing import Any, Callable
+
+from .dns import (
+    DEFAULT_TTL,
+    DNSZoneSnapshot,
+    ProviderDNSRecord,
+    _read_key_value_credentials,
+)
+
+
+DYNADOT_SUPPORTED_RECORD_TYPES = {
+    "A",
+    "AAAA",
+    "ANAME",
+    "CAA",
+    "CNAME",
+    "EMAIL",
+    "FORWARD",
+    "MX",
+    "SRV",
+    "STEALTH",
+    "TXT",
+}
+DYNADOT_API_ORIGINS = {
+    "https://api.dynadot.com",
+    "https://api-sandbox.dynadot.com",
+}
+
+
+def dynadot_signature(
+    api_key: str,
+    api_secret: str,
+    path_and_query: str,
+    request_id: str,
+    request_body: str = "",
+) -> str:
+    message = "\n".join(
+        (api_key, path_and_query, request_id or "", request_body or "")
+    )
+    digest = hmac.new(
+        api_secret.encode("utf-8"),
+        message.encode("utf-8"),
+        hashlib.sha256,
+    ).digest()
+    return base64.b64encode(digest).decode("ascii")
+
+
+def _validated_origin(value: str) -> str:
+    parsed = urllib.parse.urlsplit(value.rstrip("/"))
+    origin = f"{parsed.scheme}://{parsed.netloc}"
+    if (
+        origin not in DYNADOT_API_ORIGINS
+        or parsed.path
+        or parsed.query
+        or parsed.fragment
+        or parsed.username
+    ):
+        raise ValueError("Dynadot api_base_url is not an approved HTTPS origin")
+    return origin
+
+
+def _validated_source_cidr(value: str) -> str:
+    try:
+        network = ipaddress.ip_network(value, strict=True)
+    except ValueError as error:
+        raise ValueError("Dynadot allowed_source_cidr must be a valid CIDR") from error
+    if network.version != 4 or network.prefixlen != 32:
+        raise ValueError("Dynadot allowed_source_cidr must be an IPv4 /32")
+    return str(network)
+
+
+def _required_mapping(value: Any, message: str) -> dict[str, Any]:
+    if not isinstance(value, dict):
+        raise RuntimeError(message)
+    return value
+
+
+def _record_value(record: dict[str, Any], name: str) -> str | None:
+    value = record.get(name)
+    if value is None:
+        return None
+    if not isinstance(value, (str, int)):
+        raise RuntimeError("Dynadot returned an unsupported DNS record shape")
+    return str(value)
+
+
+class DynadotDNSProvider:
+    name = "dynadot"
+    backup_format = "json"
+
+    def __init__(
+        self,
+        *,
+        credentials: Path,
+        opener: Callable[..., Any] | None = None,
+        request_id_factory: Callable[[], str] | None = None,
+    ):
+        config = _read_key_value_credentials(credentials)
+        self.api_base_url = _validated_origin(
+            config.get("api_base_url", "")
+        )
+        self.api_key = config.get("api_key")
+        self.api_secret = config.get("api_secret")
+        self.allowed_source_cidr = _validated_source_cidr(
+            config.get("allowed_source_cidr", "")
+        )
+        if not self.api_key:
+            raise ValueError(f"missing Dynadot api_key in {credentials}")
+        if not self.api_secret:
+            raise ValueError(f"missing Dynadot api_secret in {credentials}")
+        self._opener = opener or urllib.request.urlopen
+        self._request_id_factory = request_id_factory or (
+            lambda: str(uuid.uuid4())
+        )
+
+    def get_hosts(self, domain: str) -> DNSZoneSnapshot:
+        response = self._request("GET", self._records_path(domain))
+        data = _required_mapping(
+            response.get("data"), "Dynadot DNS response omitted data"
+        )
+        glue = _required_mapping(
+            data.get("glue_info"), "Dynadot DNS response omitted glue_info"
+        )
+        glue_type = str(glue.get("glue_type", "")).upper()
+        if glue_type and glue_type != "DNS":
+            raise RuntimeError("Dynadot zone is not using Dynadot DNS")
+        ttl = glue.get("ttl", DEFAULT_TTL)
+        if not isinstance(ttl, int) or ttl < 60 or ttl > 86400:
+            raise RuntimeError("Dynadot returned an invalid zone TTL")
+        records: list[ProviderDNSRecord] = []
+        for field, name_field in (
+            ("dns_main_list", None),
+            ("dns_sub_list", "sub_host"),
+        ):
+            raw_records = glue.get(field, [])
+            if not isinstance(raw_records, list):
+                raise RuntimeError("Dynadot returned an unsupported DNS record list")
+            for raw_record in raw_records:
+                item = _required_mapping(
+                    raw_record, "Dynadot returned an unsupported DNS record"
+                )
+                record_type = str(item.get("record_type", "")).upper()
+                if record_type not in DYNADOT_SUPPORTED_RECORD_TYPES:
+                    raise RuntimeError(
+                        "Dynadot returned an unsupported DNS record type"
+                    )
+                name = "@" if name_field is None else _record_value(item, name_field)
+                value1 = _record_value(item, "value1")
+                value2 = _record_value(item, "value2")
+                if not name or value1 is None:
+                    raise RuntimeError("Dynadot returned an incomplete DNS record")
+                mx_pref = None
+                provider_value2 = value2
+                if record_type == "MX":
+                    try:
+                        mx_pref = int(value2) if value2 is not None else None
+                    except ValueError as error:
+                        raise RuntimeError(
+                            "Dynadot returned an invalid MX preference"
+                        ) from error
+                    if mx_pref is None or not 0 <= mx_pref <= 65535:
+                        raise RuntimeError("Dynadot returned an invalid MX preference")
+                    provider_value2 = None
+                records.append(
+                    ProviderDNSRecord(
+                        name=name,
+                        type=record_type,
+                        value=value1,
+                        ttl=ttl,
+                        mx_pref=mx_pref,
+                        provider_value2=provider_value2,
+                    )
+                )
+        raw = json.dumps(response, indent=2, sort_keys=True) + "\n"
+        return DNSZoneSnapshot(
+            self.name,
+            domain,
+            raw,
+            tuple(records),
+            "ok",
+            "zone fetched from Dynadot",
+            ttl,
+        )
+
+    def set_hosts(
+        self,
+        domain: str,
+        records: tuple[ProviderDNSRecord, ...],
+        *,
+        mail_policy: str,
+    ) -> None:
+        if mail_policy != "preserve":
+            raise ValueError("Dynadot full-zone updates require mail_policy=preserve")
+        if not records:
+            raise ValueError("refusing to replace a Dynadot zone with no records")
+        ttls = {int(record.ttl) for record in records}
+        if len(ttls) != 1:
+            raise ValueError("Dynadot full-zone updates require one observed zone TTL")
+        ttl = next(iter(ttls))
+        if ttl < 60 or ttl > 86400:
+            raise ValueError("Dynadot zone TTL is invalid")
+        main: list[dict[str, str]] = []
+        sub: list[dict[str, str]] = []
+        for record in records:
+            record_type = record.type.upper()
+            if record_type not in DYNADOT_SUPPORTED_RECORD_TYPES:
+                raise ValueError("Dynadot record type is unsupported")
+            item = {
+                "record_type": record_type,
+                "value1": record.value,
+            }
+            value2 = (
+                str(record.mx_pref)
+                if record_type == "MX"
+                else record.provider_value2
+            )
+            if record_type == "MX" and record.mx_pref is None:
+                raise ValueError("Dynadot MX records require mx_pref")
+            if value2 is not None:
+                item["value2"] = value2
+            normalized_name = record.name.strip().rstrip(".").lower() or "@"
+            if normalized_name == "@":
+                main.append(item)
+            else:
+                item["sub_host"] = normalized_name
+                sub.append(item)
+        if len(main) > 20 or len(sub) > 100:
+            raise ValueError("Dynadot zone exceeds documented record limits")
+        body = {
+            "dns_main_list": main,
+            "dns_sub_list": sub,
+            "ttl": ttl,
+            "add_dns_to_current_setting": False,
+        }
+        self._request("POST", self._records_path(domain), body)
+
+    @staticmethod
+    def _records_path(domain: str) -> str:
+        normalized = domain.strip().rstrip(".").lower()
+        if not normalized or "/" in normalized:
+            raise ValueError("invalid Dynadot domain")
+        return "/restful/v2/domains/" + urllib.parse.quote(normalized) + "/records"
+
+    def _request(
+        self,
+        method: str,
+        path: str,
+        body: dict[str, Any] | None = None,
+    ) -> dict[str, Any]:
+        request_body = (
+            json.dumps(body, sort_keys=True, separators=(",", ":"))
+            if body is not None
+            else ""
+        )
+        request_id = self._request_id_factory()
+        headers = {
+            "Accept": "application/json",
+            "Authorization": f"Bearer {self.api_key}",
+            "Content-Type": "application/json",
+            "X-Request-ID": request_id,
+            "X-Signature": dynadot_signature(
+                self.api_key,
+                self.api_secret,
+                path,
+                request_id,
+                request_body,
+            ),
+        }
+        request = urllib.request.Request(
+            self.api_base_url + path,
+            data=request_body.encode("utf-8") if body is not None else None,
+            headers=headers,
+            method=method,
+        )
+        try:
+            with self._opener(request, timeout=30) as response:
+                raw = response.read().decode("utf-8")
+        except urllib.error.HTTPError as error:
+            raise RuntimeError(
+                f"Dynadot API rejected {method} {path} with HTTP {error.code}"
+            ) from error
+        except urllib.error.URLError as error:
+            raise RuntimeError(
+                f"Dynadot API connectivity failed for {method} {path}"
+            ) from error
+        try:
+            document = json.loads(raw)
+        except json.JSONDecodeError as error:
+            raise RuntimeError("Dynadot API returned non-JSON data") from error
+        if not isinstance(document, dict):
+            raise RuntimeError("Dynadot API returned an unsupported response")
+        code = document.get("code")
+        if code is not None and str(code) not in {"200", "201", "0"}:
+            raise RuntimeError(f"Dynadot API rejected {method} {path}")
+        if document.get("success") is False:
+            raise RuntimeError(f"Dynadot API rejected {method} {path}")
+        return document

docs/domain-onboarding.md

@@ -1,6 +1,6 @@
 # Domain Onboarding
 
-> Status: draft | Updated 2026-07-07 | Applies to: clearnet DNS setup
+> Status: reviewed adapter contract | Updated 2026-07-31 | Applies to: clearnet DNS setup
 
 AMPG treats clearnet naming as an operator choice. A site can use a normal owned domain,
 a community free subdomain, a Dynamic DNS name, or no clearnet name at all when only
@@ -42,6 +42,15 @@ whole zone before applying. The documented Namecheap API record types do not inc
 unsupported record types and relies on TXT discovery hints unless another provider path
 is configured.
 
+Dynadot REST v2 is also supported. Its DNS update replaces the complete zone and
+uses one zone-wide TTL, so AMPG preserves every documented `value1`, `value2`, and
+`sub_host` field and refuses a write if the merged records have mixed TTLs. The
+Dynadot credential input must contain `api_base_url`, `api_key`, `api_secret`, and
+an operator-observed IPv4 `/32` `allowed_source_cidr`. Keys and signatures travel
+only in request headers. Because Dynadot labels REST v2 beta, production use also
+requires a pinned adapter commit, a sandbox proof, a connected production plan,
+and a private raw backup before the exact-zone apply.
+
 Application and service onboarding can use a secretless JSON manifest without
 creating a synthetic `gateway.toml`:
 
@@ -59,6 +68,11 @@ ampg-dns-manifest \
   --apply-zone example.com
 ```
 
+For Dynadot, omit `--client-ip` and provide the ephemeral four-field Dynadot
+credential file. A connected plan first observes the existing zone-wide TTL.
+The secretless manifest must be rendered with that exact TTL before apply;
+AMPG fails closed instead of changing the TTL on unmanaged records.
+
 The generic writer is also read-only by default. The exact `--apply-zone`
 sentinel and an absolute backup directory are mandatory for a write.
 `protected_names` can forbid all changes at sensitive names such as `@`.

tests/test_dns_manifest.py

@@ -44,6 +44,7 @@ def manifest_document():
 
 class FakeProvider:
     name = "namecheap"
+    backup_format = "xml"
 
     def __init__(self, records):
         self.records = tuple(records)
@@ -134,6 +135,62 @@ class DNSManifestTests(unittest.TestCase):
         self.assertEqual("verified", second["status"])
         self.assertEqual(1, provider.writes)
 
+    def test_dynadot_requires_observed_zone_ttl(self):
+        document = manifest_document()
+        document["provider"] = "dynadot"
+        document["records"][0]["conflict_types"] = ["CNAME", "ANAME"]
+        self.path.write_text(json.dumps(document), encoding="utf-8")
+        manifest = load_dns_manifest(self.path)
+        provider = FakeProvider([])
+        provider.name = "dynadot"
+        with self.assertRaisesRegex(Exception, "observed zone TTL"):
+            reconcile_dns_manifest(manifest, provider)
+
+    def test_provider_credentials_must_match_manifest(self):
+        manifest = load_dns_manifest(self.path)
+        provider = FakeProvider([])
+        provider.name = "dynadot"
+        with self.assertRaisesRegex(Exception, "do not match"):
+            reconcile_dns_manifest(manifest, provider)
+
+    def test_dynadot_apply_uses_json_backup_and_is_idempotent(self):
+        document = manifest_document()
+        document["provider"] = "dynadot"
+        document["records"][0]["conflict_types"] = ["CNAME", "ANAME"]
+        self.path.write_text(json.dumps(document), encoding="utf-8")
+        manifest = load_dns_manifest(self.path)
+
+        class FakeDynadot(FakeProvider):
+            name = "dynadot"
+            backup_format = "json"
+
+            def get_hosts(self, zone):
+                return DNSZoneSnapshot(
+                    self.name,
+                    zone,
+                    '{"zone":"snapshot"}\n',
+                    self.records,
+                    "ok",
+                    "ok",
+                    300,
+                )
+
+        provider = FakeDynadot(
+            [ProviderDNSRecord("@", "A", "153.75.248.86", 300)]
+        )
+        backup_dir = Path(self.temporary.name) / "backups"
+        result = reconcile_dns_manifest(
+            manifest, provider, apply=True, backup_dir=backup_dir
+        )
+        self.assertEqual("applied", result["status"])
+        self.assertTrue(result["backup_path"].endswith(".json"))
+        self.assertEqual(1, provider.writes)
+        second = reconcile_dns_manifest(
+            manifest, provider, apply=True, backup_dir=backup_dir
+        )
+        self.assertEqual("verified", second["status"])
+        self.assertEqual(1, provider.writes)
+
 
 if __name__ == "__main__":
     unittest.main()

tests/test_dynadot_dns.py

@@ -0,0 +1,158 @@
+from __future__ import annotations
+
+import base64
+import hashlib
+import hmac
+import json
+from pathlib import Path
+import tempfile
+import unittest
+
+from ampg.dns import ProviderDNSRecord
+from ampg.dynadot_dns import DynadotDNSProvider, dynadot_signature
+
+
+class FakeResponse:
+    def __init__(self, document):
+        self.document = document
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, *_arguments):
+        return False
+
+    def read(self):
+        return json.dumps(self.document).encode("utf-8")
+
+
+class DynadotDNSTests(unittest.TestCase):
+    def setUp(self):
+        self.temporary = tempfile.TemporaryDirectory()
+        self.credentials = Path(self.temporary.name) / "dynadot.ini"
+        self.credentials.write_text(
+            "api_base_url=https://api-sandbox.dynadot.com\n"
+            "api_key=test-key\n"
+            "api_secret=test-secret\n"
+            "allowed_source_cidr=192.0.2.10/32\n",
+            encoding="utf-8",
+        )
+
+    def tearDown(self):
+        self.temporary.cleanup()
+
+    def test_signature_matches_documented_hmac_shape(self):
+        message = "test-key\n/restful/v2/domains/example.test/records\nrequest-id\n"
+        expected = base64.b64encode(
+            hmac.new(
+                b"test-secret", message.encode(), hashlib.sha256
+            ).digest()
+        ).decode()
+        self.assertEqual(
+            expected,
+            dynadot_signature(
+                "test-key",
+                "test-secret",
+                "/restful/v2/domains/example.test/records",
+                "request-id",
+            ),
+        )
+
+    def test_fetch_preserves_all_provider_fields_and_secrets_stay_out_of_url(self):
+        requests = []
+
+        def opener(request, timeout):
+            requests.append(request)
+            return FakeResponse(
+                {
+                    "code": 200,
+                    "data": {
+                        "glue_info": {
+                            "glue_type": "DNS",
+                            "ttl": 1800,
+                            "dns_main_list": [
+                                {
+                                    "record_type": "MX",
+                                    "value1": "mail.example.test.",
+                                    "value2": "10",
+                                }
+                            ],
+                            "dns_sub_list": [
+                                {
+                                    "sub_host": "old",
+                                    "record_type": "FORWARD",
+                                    "value1": "https://example.test/",
+                                    "value2": "301",
+                                }
+                            ],
+                        }
+                    },
+                }
+            )
+
+        provider = DynadotDNSProvider(
+            credentials=self.credentials,
+            opener=opener,
+            request_id_factory=lambda: "550e8400-e29b-41d4-a716-446655440000",
+        )
+        snapshot = provider.get_hosts("example.test")
+        self.assertEqual(1800, snapshot.zone_ttl)
+        self.assertEqual(10, snapshot.records[0].mx_pref)
+        self.assertEqual("301", snapshot.records[1].provider_value2)
+        self.assertNotIn("test-key", requests[0].full_url)
+        self.assertNotIn("test-secret", requests[0].full_url)
+        self.assertEqual("Bearer test-key", requests[0].headers["Authorization"])
+
+    def test_full_zone_write_is_canonical_and_lossless(self):
+        requests = []
+
+        def opener(request, timeout):
+            requests.append(request)
+            return FakeResponse({"code": 200, "data": {}})
+
+        provider = DynadotDNSProvider(
+            credentials=self.credentials,
+            opener=opener,
+            request_id_factory=lambda: "550e8400-e29b-41d4-a716-446655440000",
+        )
+        provider.set_hosts(
+            "example.test",
+            (
+                ProviderDNSRecord(
+                    "@", "MX", "mail.example.test.", 1800, 10
+                ),
+                ProviderDNSRecord(
+                    "old",
+                    "FORWARD",
+                    "https://example.test/",
+                    1800,
+                    provider_value2="301",
+                ),
+            ),
+            mail_policy="preserve",
+        )
+        body = json.loads(requests[0].data)
+        self.assertFalse(body["add_dns_to_current_setting"])
+        self.assertEqual("10", body["dns_main_list"][0]["value2"])
+        self.assertEqual("301", body["dns_sub_list"][0]["value2"])
+
+    def test_mixed_ttl_and_broad_source_allowlist_fail_closed(self):
+        provider = DynadotDNSProvider(credentials=self.credentials)
+        with self.assertRaisesRegex(ValueError, "one observed"):
+            provider.set_hosts(
+                "example.test",
+                (
+                    ProviderDNSRecord("@", "A", "192.0.2.1", 300),
+                    ProviderDNSRecord("www", "A", "192.0.2.1", 1800),
+                ),
+                mail_policy="preserve",
+            )
+        self.credentials.write_text(
+            self.credentials.read_text().replace("192.0.2.10/32", "192.0.2.0/24")
+        )
+        with self.assertRaisesRegex(ValueError, "IPv4 /32"):
+            DynadotDNSProvider(credentials=self.credentials)
+
+
+if __name__ == "__main__":
+    unittest.main()