Create user setting for replacing reverse alias (default: false)

app/dashboard/templates/dashboard/setting.html

@@ -173,7 +173,6 @@
       </div>
     </div>
 
-
     <div class="card">
       <div class="card-body">
         <div class="card-title mb-3">Current Plan</div>
@@ -238,6 +237,26 @@
       </div>
     </div>
 
+    <div class="card">
+      <div class="card-body">
+        <div class="card-title">Replace reverse alias</div>
+        <div class="mb-3">
+          When replying to a reverse alias your email client will show the reverse alias ("ra+string@simplelogin.co")
+          as the original sender. This option will replace this string in the body of outgoing emails with the
+          original email address. This will break PGP signed emails, so only enable if you know what you're doing!
+        </div>
+        <form method="post">
+          <input type="hidden" name="form-name" value="replace-ra">
+          <div class="form-check">
+            <input type="checkbox" id="replace-ra" name="replace-ra"
+                   {% if current_user.replace_reverse_alias %} checked {% endif %} class="form-check-input">
+            <label for="replace-ra">Enable replacing reverse alias</label>
+          </div>
+          <button type="submit" class="btn btn-outline-primary">Submit</button>
+        </form>
+      </div>
+    </div>
+
     <div class="card">
       <div class="card-body">
         <div class="card-title">Quarantine</div>

app/dashboard/views/setting.py

@@ -160,6 +160,7 @@ def setting():
                 db.session.commit()
             flash("Your preference has been updated", "success")
             return redirect(url_for("dashboard.setting"))
+
         elif request.form.get("form-name") == "change-sender-format":
             sender_format = int(request.form.get("sender-format"))
             if SenderFormatEnum.has_value(sender_format):
@@ -169,6 +170,16 @@ def setting():
             db.session.commit()
             return redirect(url_for("dashboard.setting"))
 
+        elif request.form.get("form-name") == "replace-ra":
+            choose = request.form.get("replace-ra")
+            if choose == "on":
+                current_user.replace_reverse_alias = True
+            else:
+                current_user.replace_reverse_alias = False
+            db.session.commit()
+            flash("Your preference has been updated", "success")
+            return redirect(url_for("dashboard.setting"))
+
         elif request.form.get("form-name") == "export-data":
             data = {
                 "email": current_user.email,

app/models.py

@@ -194,6 +194,10 @@ class User(db.Model, ModelMixin, UserMixin):
         db.Integer, default="1", nullable=False, server_default="1"
     )
 
+    replace_reverse_alias = db.Column(
+        db.Boolean, default=False, nullable=False, server_default="0"
+    )
+
     referral_id = db.Column(
         db.ForeignKey("referral.id", ondelete="SET NULL"), nullable=True, default=None
     )

email_handler.py

@@ -563,14 +563,17 @@ def handle_reply(envelope, smtp: SMTP, msg: Message, rcpt_to: str) -> (bool, str
         if custom_domain.dkim_verified:
             add_dkim_signature(msg, alias_domain)
 
+    msg_raw = msg.as_string().encode()
+
     # replace the "ra+string@simplelogin.co" by the alias in the email body
     # as this is usually included in when replying
-    msg.replace(reply_email.encode(), alias.encode())
+    if user.replace_reverse_alias:
+        msg_raw = msg_raw.replace(reply_email.encode(), alias.email.encode())
 
     smtp.sendmail(
         alias.email,
         contact.website_email,
-        msg.as_bytes(),
+        msg_raw,
         envelope.mail_options,
         envelope.rcpt_options,
     )

migrations/versions/2020_051719_ce15cf3467b4_.py

@@ -0,0 +1,29 @@
+"""empty message
+
+Revision ID: ce15cf3467b4
+Revises: 659d979b64ce
+Create Date: 2020-05-17 19:38:30.255689
+
+"""
+import sqlalchemy_utils
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = 'ce15cf3467b4'
+down_revision = '659d979b64ce'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column('users', sa.Column('replace_reverse_alias', sa.Boolean(), server_default='0', nullable=False))
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_column('users', 'replace_reverse_alias')
+    # ### end Alembic commands ###