disable the PGP section if the mailbox is proton and not has PGP enabled (#1841)

* disable the PGP section if the mailbox is proton and not has PGP enabled

* fix format

---------

Co-authored-by: Son NK <son@simplelogin.io>

app/dashboard/views/mailbox_detail.py

@@ -30,7 +30,7 @@ class ChangeEmailForm(FlaskForm):
 @dashboard_bp.route("/mailbox/<int:mailbox_id>/", methods=["GET", "POST"])
 @login_required
 def mailbox_detail_route(mailbox_id):
-    mailbox = Mailbox.get(mailbox_id)
+    mailbox: Mailbox = Mailbox.get(mailbox_id)
     if not mailbox or mailbox.user_id != current_user.id:
         flash("You cannot see this page", "warning")
         return redirect(url_for("dashboard.index"))
@@ -144,6 +144,15 @@ def mailbox_detail_route(mailbox_id):
                         url_for("dashboard.mailbox_detail_route", mailbox_id=mailbox_id)
                     )
 
+                if mailbox.is_proton():
+                    flash(
+                        "Enabling PGP for a Proton Mail mailbox is redundant and does not add any security benefit",
+                        "info",
+                    )
+                    return redirect(
+                        url_for("dashboard.mailbox_detail_route", mailbox_id=mailbox_id)
+                    )
+
                 mailbox.pgp_public_key = request.form.get("pgp")
                 try:
                     mailbox.pgp_finger_print = load_public_key_and_check(

app/dns_utils.py

@@ -34,7 +34,7 @@ def get_cname_record(hostname) -> Optional[str]:
 
 
 def get_mx_domains(hostname) -> [(int, str)]:
-    """return list of (priority, domain name).
+    """return list of (priority, domain name) sorted by priority (lowest priority first)
     domain name ends with a "." at the end.
     """
     try:
@@ -50,7 +50,7 @@ def get_mx_domains(hostname) -> [(int, str)]:
 
         ret.append((int(parts[0]), parts[1]))
 
-    return ret
+    return sorted(ret, key=lambda prio_domain: prio_domain[0])
 
 
 _include_spf = "include:"

app/models.py

@@ -30,6 +30,8 @@ from sqlalchemy_utils import ArrowType
 from app import config
 from app import s3
 from app.db import Session
+from app.dns_utils import get_mx_domains
+
 from app.errors import (
     AliasInTrashError,
     DirectoryInTrashError,
@@ -2569,6 +2571,27 @@ class Mailbox(Base, ModelMixin):
             + Alias.filter_by(mailbox_id=self.id).count()
         )
 
+    def is_proton(self) -> bool:
+        if (
+            self.email.endswith("@proton.me")
+            or self.email.endswith("@protonmail.com")
+            or self.email.endswith("@protonmail.ch")
+            or self.email.endswith("@pm.me")
+        ):
+            return True
+
+        from app.email_utils import get_email_local_part
+
+        mx_domains: [(int, str)] = get_mx_domains(get_email_local_part(self.email))
+        # Proton is the first domain
+        if mx_domains and mx_domains[0][1] in (
+            "mail.protonmail.ch.",
+            "mailsec.protonmail.ch.",
+        ):
+            return True
+
+        return False
+
     @classmethod
     def delete(cls, obj_id):
         mailbox: Mailbox = cls.get(obj_id)

templates/dashboard/mailbox_detail.html

@@ -71,98 +71,110 @@
         </form>
       </div>
       <!-- END Change email -->
-      {% if mailbox.pgp_finger_print and not mailbox.disable_pgp and current_user.include_sender_in_reverse_alias %}
+      <!-- Not show PGP option for Proton mailbox -->
+      {% if mailbox.is_proton() and not mailbox.pgp_enabled() %}
 
         <div class="alert alert-info">
-          Email headers like <span class="italic">From, To, Subject</span> aren't encrypted by PGP.
+          As an email is always encrypted at rest in Proton Mail, having SimpleLogin also encrypt your email is redundant and does not add any security benefit.
-          Currently, your reverse alias includes the sender address.
+          <br>
-          You can disable this on <a href="/dashboard/setting#sender-in-ra">Settings</a>.
+          The PGP option on SimpleLogin is instead useful for when your mailbox provider isn't encrypted by default like Gmail, Outlook, etc.
         </div>
       {% endif %}
-      <div class="card">
+      <div class="{% if mailbox.is_proton() and not mailbox.pgp_enabled() %}
-        <div class="card-body">
+         disabled-content{% endif %}">
-          <div class="card-title">
+        {% if mailbox.pgp_finger_print and not mailbox.disable_pgp and current_user.include_sender_in_reverse_alias and not mailbox.is_proton() %}
-            <div class="d-flex">
-              Pretty Good Privacy (PGP)
-              {% if mailbox.pgp_finger_print %}
 
-                <form method="post">
+          <div class="alert alert-info">
-                  {{ csrf_form.csrf_token }}
+            Email headers like <span class="italic">From, To, Subject</span> aren't encrypted by PGP.
-                  <input type="hidden" name="form-name" value="toggle-pgp">
+            Currently, your reverse alias includes the sender address.
-                  <label class="custom-switch cursor" style="padding-left: 1rem" data-toggle="tooltip" {% if mailbox.disable_pgp %}
+            You can disable this on <a href="/dashboard/setting#sender-in-ra">Settings</a>.
-                     title="Enable PGP" {% else %} title="Disable PGP" {% endif %}>
-                    <input type="checkbox" class="custom-switch-input" name="pgp-enabled" {{ "" if mailbox.disable_pgp else "checked" }}>
-                    <span class="custom-switch-indicator"></span>
-                  </label>
-                </form>
-              {% endif %}
-            </div>
-            <div class="small-text mt-1">
-              By importing your PGP Public Key into SimpleLogin, all emails sent to {{ mailbox.email }} are
-              <b>encrypted</b> with your key.
-              <br />
-              {% if PGP_SIGNER %}All forwarded emails will be signed with <b>{{ PGP_SIGNER }}</b>.{% endif %}
-            </div>
           </div>
-          {% if not current_user.is_premium() %}
+        {% endif %}
-
+        <div class="card">
-            <div class="alert alert-danger" role="alert">This feature is only available in premium plan.</div>
-          {% endif %}
-          <form method="post">
-            {{ csrf_form.csrf_token }}
-            <div class="form-group">
-              <label class="form-label">PGP Public Key</label>
-              <textarea name="pgp" {% if not current_user.is_premium() %} disabled {% endif %} class="form-control" rows=10 id="pgp-public-key" placeholder="(Drag and drop or paste your pgp public key here)&#10;-----BEGIN PGP PUBLIC KEY BLOCK-----">{{ mailbox.pgp_public_key or "" }}</textarea>
-            </div>
-            <input type="hidden" name="form-name" value="pgp">
-            <button class="btn btn-primary" name="action" {% if not current_user.is_premium() %}
-               disabled {% endif %} value="save">
-              Save
-            </button>
-            {% if mailbox.pgp_finger_print %}
-
-              <button class="btn btn-danger float-right" name="action" value="remove">Remove</button>
-            {% endif %}
-          </form>
-        </div>
-      </div>
-      <div class="card" {% if not mailbox.pgp_enabled() %}
-         disabled {% endif %}>
-        <form method="post">
-          {{ csrf_form.csrf_token }}
-          <input type="hidden" name="form-name" value="generic-subject">
           <div class="card-body">
             <div class="card-title">
-              Hide email subject when PGP is enabled
+              <div class="d-flex">
+                Pretty Good Privacy (PGP)
+                {% if mailbox.pgp_finger_print %}
+
+                  <form method="post">
+                    {{ csrf_form.csrf_token }}
+                    <input type="hidden" name="form-name" value="toggle-pgp">
+                    <label class="custom-switch cursor" style="padding-left: 1rem" data-toggle="tooltip" {% if mailbox.disable_pgp %}
+                       title="Enable PGP" {% else %} title="Disable PGP" {% endif %}>
+                      <input type="checkbox" class="custom-switch-input" name="pgp-enabled" {{ "" if mailbox.disable_pgp else "checked" }}>
+                      <span class="custom-switch-indicator"></span>
+                    </label>
+                  </form>
+                {% endif %}
+              </div>
               <div class="small-text mt-1">
-                When PGP is enabled, you can choose to use a <b>generic</b> subject for the forwarded emails.
+                By importing your PGP Public Key into SimpleLogin, all emails sent to {{ mailbox.email }} are
-                The original subject is then added into the email body.
+                <b>encrypted</b> with your key.
                 <br />
-                As PGP does not encrypt the email subject and the email subject might contain sensitive information,
+                {% if PGP_SIGNER %}All forwarded emails will be signed with <b>{{ PGP_SIGNER }}</b>.{% endif %}
-                this option will allow a further protection of your email content.
               </div>
             </div>
-            <div class="alert alert-info">
+            {% if not current_user.is_premium() %}
-              As the email is encrypted, a subject like "Email for you"
+
-              will probably be rejected by your mailbox since it sounds like a spam.
+              <div class="alert alert-danger" role="alert">This feature is only available in premium plan.</div>
-              <br />
+            {% endif %}
-              Something like "Encrypted Email" would work much better :).
+            <form method="post">
-            </div>
+              {{ csrf_form.csrf_token }}
-            <div class="form-group">
+              <div class="form-group">
-              <label class="form-label">Generic Subject</label>
+                <label class="form-label">PGP Public Key</label>
-              <input name="generic-subject" {% if not mailbox.pgp_enabled() %}
+                <textarea name="pgp" {% if not current_user.is_premium() %} disabled {% endif %} class="form-control" rows=10 id="pgp-public-key" placeholder="(Drag and drop or paste your pgp public key here)&#10;-----BEGIN PGP PUBLIC KEY BLOCK-----">{{ mailbox.pgp_public_key or "" }}</textarea>
-                 disabled {% endif %} class="form-control" maxlength="78" placeholder="Generic Subject" value="{{ mailbox.generic_subject or "" }}">
               </div>
-              <button class="btn btn-primary" name="action" {% if not mailbox.pgp_enabled() %}
+              <input type="hidden" name="form-name" value="pgp">
+              <button class="btn btn-primary" name="action" {% if not current_user.is_premium() %}
                  disabled {% endif %} value="save">
                 Save
               </button>
-              {% if mailbox.generic_subject %}
+              {% if mailbox.pgp_finger_print %}
 
                 <button class="btn btn-danger float-right" name="action" value="remove">Remove</button>
               {% endif %}
-            </div>
+            </form>
-          </form>
+          </div>
+        </div>
+        <div class="card" {% if not mailbox.pgp_enabled() %}
+           disabled {% endif %}>
+          <form method="post">
+            {{ csrf_form.csrf_token }}
+            <input type="hidden" name="form-name" value="generic-subject">
+            <div class="card-body">
+              <div class="card-title">
+                Hide email subject when PGP is enabled
+                <div class="small-text mt-1">
+                  When PGP is enabled, you can choose to use a <b>generic</b> subject for the forwarded emails.
+                  The original subject is then added into the email body.
+                  <br />
+                  As PGP does not encrypt the email subject and the email subject might contain sensitive information,
+                  this option will allow a further protection of your email content.
+                </div>
+              </div>
+              <div class="alert alert-info">
+                As the email is encrypted, a subject like "Email for you"
+                will probably be rejected by your mailbox since it sounds like a spam.
+                <br />
+                Something like "Encrypted Email" would work much better :).
+              </div>
+              <div class="form-group">
+                <label class="form-label">Generic Subject</label>
+                <input name="generic-subject" {% if not mailbox.pgp_enabled() %}
+                   disabled {% endif %} class="form-control" maxlength="78" placeholder="Generic Subject" value="{{ mailbox.generic_subject or "" }}">
+                </div>
+                <button class="btn btn-primary" name="action" {% if not mailbox.pgp_enabled() %}
+                   disabled {% endif %} value="save">
+                  Save
+                </button>
+                {% if mailbox.generic_subject %}
+
+                  <button class="btn btn-danger float-right" name="action" value="remove">Remove</button>
+                {% endif %}
+              </div>
+            </form>
+          </div>
         </div>
         <hr />
         <h2 class="h4">Advanced Options</h2>