NEW FEATURE: M365_BUILDER() (Microsoft 365 builder) (#2365)

Co-authored-by: Tom Limoncelli <tlimoncelli@stackoverflow.com>

commands/types/dnscontrol.d.ts

@@ -2408,6 +2408,55 @@ declare function LOC_BUILDER_DMS_STR(opts: { label?: string; str: string; alt?:
  */
 declare function LOC_BUILDER_STR(opts: { label?: string; str: string; alt?: number; ttl?: Duration }): RecordModifier;
 
+/**
+ * DNSControl offers a `M365_BUILDER` which can be used to simply set up Microsoft 365 for a domain in an opinionated way.
+ * 
+ * It defaults to a setup without support for legacy Skype for Business applications.
+ * It doesn't set up SPF or DMARC. See [`SPF_BUILDER`](/language-reference/record-modifiers/dmarc_builder) and [`DMARC_BUILDER`](/language-reference/record-modifiers/spf_builder).
+ * 
+ * ## Example
+ * 
+ * ### Simple example
+ * 
+ * ```javascript
+ * M365_BUILDER({
+ *     initialDomain: 'example.onmicrosoft.com',
+ * });
+ * ```
+ * 
+ * This sets up `MX` records, Autodiscover, and DKIM.
+ * 
+ * ### Advanced example
+ * 
+ * ```javascript
+ * M365_BUILDER({
+ *     label: 'test',
+ *     mx: false,
+ *     autodiscover: false,
+ *     dkim: false,
+ *     mdm: true,
+ *     domainGUID: 'test-example-com', // Can be automatically derived in this case, if example.com is the context.
+ *     initialDomain: 'example.onmicrosoft.com',
+ * });
+ * ```
+ * 
+ * This sets up Mobile Device Management only.
+ * 
+ * ### Parameters
+ * 
+ * * `label` The label of the Microsoft 365 domain, useful if it is a subdomain (default: `'@'`)
+ * * `mx` Set an `MX` record? (default: `true`)
+ * * `autodiscover` Set Autodiscover `CNAME` record? (default: `true`)
+ * * `dkim` Set DKIM `CNAME` records? (default: `true`)
+ * * `skypeForBusiness` Set Skype for Business/Microsoft Teams records? (default: `false`)
+ * * `mdm` Set Mobile Device Management records? (default: `false`)
+ * * `domainGUID` The GUID of _this_ Microsoft 365 domain (default: `<label>.<context>` with `.` replaced by `-`, no default if domain contains dashes)
+ * * `initialDomain` The initial domain of your Microsoft 365 tenant/account, ends in `onmicrosoft.com`
+ * 
+ * @see https://docs.dnscontrol.org/language-reference/record-modifiers/m365_builder
+ */
+declare function M365_BUILDER(opts: { label?: string; mx?: boolean; autodiscover?: boolean; dkim?: boolean; skypeForBusiness?: boolean; mdm?: boolean; domainGUID?: string; initialDomain?: string }): RecordModifier;
+
 /**
  * R53_ZONE lets you specify the AWS Zone ID for an entire domain (D()) or a specific R53_ALIAS() record.
  * 

documentation/functions/record/M365_BUILDER.md

@@ -0,0 +1,70 @@
+---
+name: M365_BUILDER
+parameters:
+  - label
+  - mx
+  - autodiscover
+  - dkim
+  - skypeForBusiness
+  - mdm
+  - domainGUID
+  - initialDomain
+parameters_object: true
+parameter_types:
+  label: string?
+  mx: boolean?
+  autodiscover: boolean?
+  dkim: boolean?
+  skypeForBusiness: boolean?
+  mdm: boolean?
+  domainGUID: string?
+  initialDomain: string?
+---
+
+DNSControl offers a `M365_BUILDER` which can be used to simply set up Microsoft 365 for a domain in an opinionated way.
+
+It defaults to a setup without support for legacy Skype for Business applications.
+It doesn't set up SPF or DMARC. See [`SPF_BUILDER`](/language-reference/record-modifiers/dmarc_builder) and [`DMARC_BUILDER`](/language-reference/record-modifiers/spf_builder).
+
+## Example
+
+### Simple example
+
+{% code title="dnsconfig.js" %}
+```javascript
+M365_BUILDER({
+    initialDomain: 'example.onmicrosoft.com',
+});
+```
+{% endcode %}
+
+This sets up `MX` records, Autodiscover, and DKIM.
+
+### Advanced example
+
+{% code title="dnsconfig.js" %}
+```javascript
+M365_BUILDER({
+    label: 'test',
+    mx: false,
+    autodiscover: false,
+    dkim: false,
+    mdm: true,
+    domainGUID: 'test-example-com', // Can be automatically derived in this case, if example.com is the context.
+    initialDomain: 'example.onmicrosoft.com',
+});
+```
+{% endcode %}
+
+This sets up Mobile Device Management only.
+
+### Parameters
+
+* `label` The label of the Microsoft 365 domain, useful if it is a subdomain (default: `'@'`)
+* `mx` Set an `MX` record? (default: `true`)
+* `autodiscover` Set Autodiscover `CNAME` record? (default: `true`)
+* `dkim` Set DKIM `CNAME` records? (default: `true`)
+* `skypeForBusiness` Set Skype for Business/Microsoft Teams records? (default: `false`)
+* `mdm` Set Mobile Device Management records? (default: `false`)
+* `domainGUID` The GUID of _this_ Microsoft 365 domain (default: `<label>.<context>` with `.` replaced by `-`, no default if domain contains dashes)
+* `initialDomain` The initial domain of your Microsoft 365 tenant/account, ends in `onmicrosoft.com`

pkg/js/helpers.js

@@ -1633,6 +1633,134 @@ function DMARC_BUILDER(value) {
     return TXT(label, record.join('; '));
 }
 
+// Documentation of the records: https://learn.microsoft.com/en-us/microsoft-365/enterprise/external-domain-name-system-records?view=o365-worldwide
+function M365_BUILDER(name, value) {
+    // value is optional
+    if (!value) {
+        value = {};
+    }
+
+    if (value.mx !== false) {
+        value.mx = true;
+    }
+    if (value.autodiscover !== false) {
+        value.autodiscover = true;
+    }
+    if (value.dkim !== false) {
+        value.dkim = true;
+    }
+
+    if (!value.label) {
+        value.label = '@';
+    }
+
+    if (!value.domainGUID) {
+        // Does not work with dashes in domain name.
+        // Microsoft uses its own, (probably) deterministic algorithm to transform these domains.
+        // Unfortunately, underlying algorithm is not known to us.
+        if (name.indexOf('-') !== -1) {
+            throw (
+                'M365_BUILDER requires domainGUID for domains with dashes: ' +
+                name
+            );
+        }
+
+        value.domainGUID = name.replace('.', '-');
+    }
+
+    if (value.dkim && !value.initialDomain) {
+        throw (
+            "M365_BUILDER requires your M365 account's initial domain to set up DKIM (default: enabled): " +
+            name
+        );
+    }
+
+    r = [];
+
+    // MX (default: true)
+    if (value.mx) {
+        r.push(
+            MX(
+                value.label,
+                0,
+                value.domainGUID + '.mail.protection.outlook.com.'
+            )
+        );
+    }
+
+    // Autodiscover (default: true)
+    if (value.autodiscover) {
+        if ((value.label = '@')) {
+            r.push(CNAME('autodiscover', 'autodiscover.outlook.com.'));
+        } else {
+            r.push(
+                CNAME(
+                    'autodiscover.' + value.label,
+                    'autodiscover.outlook.com.'
+                )
+            );
+        }
+    }
+
+    // DKIM (default: true)
+    if (value.dkim) {
+        r.push(
+            CNAME(
+                'selector1._domainkey',
+                'selector1-' +
+                    value.domainGUID +
+                    '._domainkey.' +
+                    value.initialDomain +
+                    '.'
+            )
+        );
+        r.push(
+            CNAME(
+                'selector2._domainkey',
+                'selector2-' +
+                    value.domainGUID +
+                    '._domainkey.' +
+                    value.initialDomain +
+                    '.'
+            )
+        );
+    }
+
+    // Skype for Business (default: false)
+    if (value.skypeForBusiness) {
+        r.push(CNAME('lyncdiscover', 'webdir.online.lync.com.'));
+        r.push(CNAME('sip', 'sipdir.online.lync.com.'));
+        r.push(SRV('_sip._tls', 100, 1, 443, 'sipdir.online.lync.com.'));
+        r.push(
+            SRV(
+                '_sipfederationtls._tcp',
+                100,
+                1,
+                5061,
+                'sipfed.online.lync.com.'
+            )
+        );
+    }
+
+    // Mobile Device Management (default: false)
+    if (value.mdm) {
+        r.push(
+            CNAME(
+                'enterpriseregistration',
+                'enterpriseregistration.windows.net.'
+            )
+        );
+        r.push(
+            CNAME(
+                'enterpriseenrollment',
+                'enterpriseenrollment.manage.microsoft.com.'
+            )
+        );
+    }
+
+    return r;
+}
+
 // This is a no-op.  Long TXT records are handled natively now.
 function DKIM(arr) {
     return arr;