showing login address in logs

Hi,

Can someone help me?
I have 2 IP addresses on ether1 (192.168.1.1 and 192.168.1.2 with masquerade), and I have to write out in the logs to which address logs in.
I’m using winbox and logstash to get logs from Mikrotik, but only I get host IP (192.168.1.1, which sending logs to logstash). It’s possible to do it with grok only, or I have to configure Mikrotik?

Grok:

input {
  udp {
    port => 514
    type => "syslog"
  }
}

filter {
  grok {
    match => {
      "message" => "%{DATA:topics} user %{WORD:user_name} logged %{WORD:action} from %{IP:src_ip} via %{WORD:protocol}"
    }
  }
}

output {
  stdout { codec => rubydebug }

  elasticsearch {
    hosts => ["http://localhost:9200"]
    index => "mikrotik-logs-%{+YYYY.MM.dd}"
  }

  file {
    path => "C:/logs/mikrotik_logs_%{+YYYY-MM-dd}.log"
    codec => line { format => "%{message} TO_IP: %{host}" }
  }
}

/ip fi ma add action=log chain=input dst-address=192.168.1.1 dst-port=8291 log-prefix=Winbox_x1 protocol=tcp
/ip fi ma add action=log chain=input dst-address=192.168.1.2 dst-port=8291 log-prefix=Winbox_x2 protocol=tcp