Unable to locate function body: ip_nat_init()

Hi, I am going through the networking code for the stable release. In the file ip_input.c there is a call to a function ip_nat_init() in the function ip_init(). However I have been unable to locate the code for this function (ip_nat_init()). Could somebody please tell me in which file i

Unable to locate function body: ip_nat_init()

Hi,   I am going through the networking code for the stable release.   In the file ip_input.c  there is a call to a function ip_nat_init() in the function   ip_init(). However I have been unable to locate the code for this function (ip_nat_init()).     Could somebody please tell me in which