diff --git a/lib/CMTD/Main.pm b/lib/CMTD/Main.pm
index 0577d31..09488de 100644
--- a/lib/CMTD/Main.pm
+++ b/lib/CMTD/Main.pm
@@ -6,6 +6,8 @@ use utf8;
 
 use Mojo::Base 'Mojolicious::Controller';
 
+use Mojo::Util qw(trim);
+
 sub index {
   my ($self) = @_;
 
@@ -75,15 +77,52 @@ sub c_add {
     return;
   }
 
-  my $site = $self->app->sites->{ $ref->{site} };
-  unless ($site and ref($site) eq 'HASH') {
-    $self->res->code(400);
-    $self->render(text => "no such site\n");
-    return;
-  }
-
   eval {
-    1;
+    my (%msg, %cap);
+    $msg{addr} = $self->tx->remote_address;
+    foreach my $param (qw(name email text reply)) {
+      $msg{$param} = trim($self->req->param($param) || '');
+    }
+    foreach my $param (qw(cid code)) {
+      $cap{$param} = trim($self->req->param($param) || '');
+    }
+    do {{
+      unless ($msg{text}) {
+        $self->res->code(400);
+        $self->render(text => "empty message\n");
+        last;
+      }
+      my $sid = $self->app->sid_by_name($ref->{site});
+      unless ($sid) {
+        $self->res->code(400);
+        $self->render(text => "no such site\n");
+        last;
+      }
+      if ($cap{cid}) {
+        unless ($cap{code}) {
+          $self->res->code(400);
+          $self->render(text => "missing captcha code\n");
+          last;
+        }
+        my $cap = $self->captcha_by_id($cap{cid});
+        unless ($cap and $cap eq 'HASH') {
+          $self->res->code(400);
+          $self->render(text => "no captcha with this id\n");
+          last;
+        }
+        unless ($cap->{code} eq $cap{code}) {
+          $self->res->code(400);
+          $self->render(text => "captcha code mismatch\n");
+          last;
+        }
+      }
+      my $pid = $self->app->pid_by_hash($sid, $ref->{hash});
+      unless ($pid) {
+        $self->app->add_page($sid, $ref);
+        $pid = $self->app->pid_by_hash($sid, $ref->{hash});
+      }
+      $self->add_comment($pid, \%msg);
+    }} while (0); 1;
   } or do {
     chomp $@;
     my $msg = sprintf "Error when listing comments for %s/%s: %s",