Method: ActionDispatch::RemoteIp::GetIp#calculate_ip
- Defined in:
- actionpack/lib/action_dispatch/middleware/remote_ip.rb
#calculate_ip ⇒ Object
Determines originating IP address. REMOTE_ADDR is the standard but will be wrong if the user is behind a proxy. Proxies will set HTTP_CLIENT_IP and/or HTTP_X_FORWARDED_FOR, so we prioritize those. HTTP_X_FORWARDED_FOR may be a comma-delimited list in the case of multiple chained proxies. The last address which is not a known proxy will be the originating IP.
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# File 'actionpack/lib/action_dispatch/middleware/remote_ip.rb', line 47 def calculate_ip client_ip = @env['HTTP_CLIENT_IP'] forwarded_ips = ips_from('HTTP_X_FORWARDED_FOR') remote_addrs = ips_from('REMOTE_ADDR') check_ip = client_ip && @middleware.check_ip if check_ip && !forwarded_ips.include?(client_ip) # We don't know which came from the proxy, and which from the user raise IpSpoofAttackError, "IP spoofing attack?!" \ "HTTP_CLIENT_IP=#{@env['HTTP_CLIENT_IP'].inspect}" \ "HTTP_X_FORWARDED_FOR=#{@env['HTTP_X_FORWARDED_FOR'].inspect}" end not_proxy = client_ip || forwarded_ips.last || remote_addrs.first # Return first REMOTE_ADDR if there are no other options not_proxy || ips_from('REMOTE_ADDR', :allow_proxies).first end |