From 6a42673229dcf5a2299b945ab68dd312096f36e7 Mon Sep 17 00:00:00 2001
From: Son NK <>
Date: Sun, 3 May 2020 11:19:14 +0200
Subject: [PATCH] remove the copy button, use CNAME for DKIM

---
 .../dashboard/domain_detail/dns.html          | 51 ++++++++++---------
 app/dashboard/views/domain_detail.py          | 19 +++----
 app/dns_utils.py                              | 15 ++++++
 3 files changed, 53 insertions(+), 32 deletions(-)

diff --git a/app/dashboard/templates/dashboard/domain_detail/dns.html b/app/dashboard/templates/dashboard/domain_detail/dns.html
index 30657e51..4a6d9a24 100644
--- a/app/dashboard/templates/dashboard/domain_detail/dns.html
+++ b/app/dashboard/templates/dashboard/domain_detail/dns.html
@@ -28,19 +28,21 @@
       </div>
 
       <div class="mb-2">Add the following MX DNS record to your domain. <br>
-        Please note that there's a point (<em>.</em>) at the end target addresses. <br>
+        Please note that there's a point (<em>.</em>) at the end target addresses.
+        This is to make sure the <i>absolute</i> address is used.
+        <br>
         Also some domain registrars (Namecheap, CloudFlare, etc) might use <em>@</em> for the root domain.
       </div>
 
       {% for priority, email_server in EMAIL_SERVERS_WITH_PRIORITY %}
         <div class="mb-3 p-3" style="background-color: #eee">
-          Domain: <em>{{ custom_domain.domain }}</em> or <em>@</em> <br>
+          Record: MX <br>
+          Domain: {{ custom_domain.domain }} or @ <br>
           Priority: {{ priority }} <br>
-          Target: <em>{{ email_server }}</em>
-          <button class="ml-4 clipboard btn btn-sm btn-outline-success" data-clipboard-action="copy"
-                  data-clipboard-text="{{ email_server }}">
-            Copy <i class="fe fe-clipboard"></i>
-          </button>
+          Target: <em data-toggle="tooltip"
+                      title="Click to copy"
+                      class="clipboard"
+                      data-clipboard-text="{{ email_server }}">{{ email_server }}</em>
         </div>
       {% endfor %}
 
@@ -93,18 +95,18 @@
         Setting up SPF is highly recommended to reduce the chance your emails ending up in the recipient's Spam folder.
       </div>
 
-      <div class="mb-2">Add the following TXT DNS record to your domain</div>
+      <div class="mb-2">Add the following TXT DNS record to your domain.</div>
 
       <div class="mb-2 p-3" style="background-color: #eee">
-        Domain: <em>{{ custom_domain.domain }}</em> or <em>@</em> <br>
+        Record: TXT <br>
+        Domain: {{ custom_domain.domain }} or @ <br>
         Value:
-        <em>
+        <em data-toggle="tooltip"
+            title="Click to copy"
+            class="clipboard"
+            data-clipboard-text="{{ spf_record }}">
           {{ spf_record }}
         </em>
-        <button class="ml-4 clipboard btn btn-sm btn-outline-success" data-clipboard-action="copy"
-                data-clipboard-text="{{ spf_record }}">
-          Copy <i class="fe fe-clipboard"></i>
-        </button>
       </div>
 
       <form method="post" action="#spf-form">
@@ -158,18 +160,21 @@
         Setting up DKIM is highly recommended to reduce the chance your emails ending up in the recipient's Spam folder.
       </div>
 
-      <div class="mb-2">Add the following TXT DNS record to your domain</div>
+      <div class="mb-2">Add the following CNAME DNS record to your domain.</div>
 
       <div class="mb-2 p-3" style="background-color: #eee">
-        Domain: <em>dkim._domainkey.{{ custom_domain.domain }}</em> <br>
+        Record: CNAME <br>
+        Domain: <em data-toggle="tooltip"
+                    title="Click to copy"
+                    class="clipboard"
+                    data-clipboard-text="dkim._domainkey.">dkim._domainkey.</em>{{ custom_domain.domain }} <br>
         Value:
-        <em style="overflow-wrap: break-word">
-          {{ dkim_record }}
+        <em data-toggle="tooltip"
+            title="Click to copy"
+            class="clipboard"
+            data-clipboard-text="{{ dkim_cname }}" style="overflow-wrap: break-word">
+          {{ dkim_cname }}
         </em>
-        <button class="ml-4 clipboard btn btn-sm btn-outline-success" data-clipboard-action="copy"
-                data-clipboard-text="{{ dkim_record }}">
-          Copy <i class="fe fe-clipboard"></i>
-        </button>
       </div>
 
       <form method="post" action="#dkim-form">
@@ -189,7 +194,7 @@
         <div class="text-danger mt-4">
           Your DNS is not correctly set.
           {% if dkim_errors %}
-            The TXT record we obtain for
+            The CNAME record we obtain for
             <em>dkim._domainkey.{{ custom_domain.domain }}</em> is:
 
             <div class="mb-3 p-3" style="background-color: #eee">
diff --git a/app/dashboard/views/domain_detail.py b/app/dashboard/views/domain_detail.py
index b8cdbcad..544875e4 100644
--- a/app/dashboard/views/domain_detail.py
+++ b/app/dashboard/views/domain_detail.py
@@ -8,6 +8,7 @@ from app.dns_utils import (
     get_spf_domain,
     get_dkim_record,
     get_txt_record,
+    get_cname_record,
 )
 from app.extensions import db
 from app.models import CustomDomain, Alias
@@ -21,6 +22,11 @@ def domain_detail_dns(custom_domain_id):
         flash("You cannot see this page", "warning")
         return redirect(url_for("dashboard.index"))
 
+    spf_record = f"v=spf1 include:{EMAIL_DOMAIN} -all"
+
+    # hardcode the DKIM selector here
+    dkim_cname = f"dkim._domainkey.{EMAIL_DOMAIN}"
+
     mx_ok = spf_ok = dkim_ok = True
     mx_errors = spf_errors = dkim_errors = []
 
@@ -67,9 +73,8 @@ def domain_detail_dns(custom_domain_id):
                 spf_errors = get_txt_record(custom_domain.domain)
 
         elif request.form.get("form-name") == "check-dkim":
-            dkim_record = get_dkim_record(custom_domain.domain)
-            correct_dkim_record = f"v=DKIM1; k=rsa; p={DKIM_DNS_VALUE}"
-            if dkim_record == correct_dkim_record:
+            dkim_record = get_cname_record(custom_domain.domain)
+            if dkim_record == dkim_cname:
                 flash("The DKIM is setup correctly.", "success")
                 custom_domain.dkim_verified = True
                 db.session.commit()
@@ -80,13 +85,9 @@ def domain_detail_dns(custom_domain_id):
                     )
                 )
             else:
-                flash("DKIM: the TXT record is not correctly set", "warning")
+                flash("DKIM: the CNAME record is not correctly set", "warning")
                 dkim_ok = False
-                dkim_errors = get_txt_record(f"dkim._domainkey.{custom_domain.domain}")
-
-    spf_record = f"v=spf1 include:{EMAIL_DOMAIN} -all"
-
-    dkim_record = f"v=DKIM1; k=rsa; p={DKIM_DNS_VALUE}"
+                dkim_errors = [dkim_record or "[Empty]"]
 
     return render_template(
         "dashboard/domain_detail/dns.html",
diff --git a/app/dns_utils.py b/app/dns_utils.py
index 1dbae850..052c71d5 100644
--- a/app/dns_utils.py
+++ b/app/dns_utils.py
@@ -1,3 +1,5 @@
+from typing import Optional
+
 import dns.resolver
 
 
@@ -10,6 +12,19 @@ def _get_dns_resolver():
     return my_resolver
 
 
+def get_cname_record(hostname) -> Optional[str]:
+    """Return the CNAME record if exists for a domain"""
+    try:
+        answers = _get_dns_resolver().query(hostname, "CNAME")
+    except Exception:
+        return None
+
+    for a in answers:
+        return a
+
+    return None
+
+
 def get_mx_domains(hostname) -> [(int, str)]:
     """return list of (priority, domain name).
     domain name ends with a "." at the end.