ipsec strongswan (linux <--> cisco )

 iptables -t nat -A POSTROUTING -s 192.168.1.0/24 ! -d 192.168.0.0/16 -j SNAT --to-source x.x.x.x

# ipsec.conf - strongSwan IPsec configuration file

# basic configuration

config setup
    # plutodebug=all
    # crlcheckinterval=600
    # strictcrlpolicy=yes
    # cachecrls=yes
    #nat_traversal=yes
    charonstart=yes
    plutostart=yes
       

conn %default
      left=x.x.x.x
      leftsubnet=192.168.1.0/24
      leftsourceip=192.168.1.1
      leftid=x.x.x.x
      auth=esp
      type=tunnel
      authby=secret
      esp=3des-sha1-modp1024
      ike=3des-sha1-modp1024
      keyexchange=ikev1
      keyingtries=0
      leftfirewall=yes

conn office
      right=y.y.y.y
      rightsubnet=192.168.190.0/24
      rightid=y.y.y.y
      auto=start


include /var/lib/strongswan/ipsec.conf.inc