diff options
Diffstat (limited to 'actionpack/lib/action_dispatch/middleware/remote_ip.rb')
| -rw-r--r-- | actionpack/lib/action_dispatch/middleware/remote_ip.rb | 148 |
1 files changed, 113 insertions, 35 deletions
diff --git a/actionpack/lib/action_dispatch/middleware/remote_ip.rb b/actionpack/lib/action_dispatch/middleware/remote_ip.rb index c7d710b98e..ec15a2a715 100644 --- a/actionpack/lib/action_dispatch/middleware/remote_ip.rb +++ b/actionpack/lib/action_dispatch/middleware/remote_ip.rb @@ -2,50 +2,128 @@ module ActionDispatch class RemoteIp class IpSpoofAttackError < StandardError ; end - class RemoteIpGetter - def initialize(env, check_ip_spoofing, trusted_proxies) - @env = env - @check_ip_spoofing = check_ip_spoofing - @trusted_proxies = trusted_proxies + # IP addresses that are "trusted proxies" that can be stripped from + # the comma-delimited list in the X-Forwarded-For header. See also: + # http://en.wikipedia.org/wiki/Private_network#Private_IPv4_address_spaces + # http://en.wikipedia.org/wiki/Private_network#Private_IPv6_addresses. + TRUSTED_PROXIES = %r{ + ^127\.0\.0\.1$ | # localhost + ^::1$ | + ^(10 | # private IP 10.x.x.x + 172\.(1[6-9]|2[0-9]|3[0-1]) | # private IP in the range 172.16.0.0 .. 172.31.255.255 + 192\.168 | # private IP 192.168.x.x + fc00:: # private IP fc00 + )\. + }x + + attr_reader :check_ip, :proxies + + def initialize(app, check_ip_spoofing = true, custom_proxies = nil) + @app = app + @check_ip = check_ip_spoofing + @proxies = case custom_proxies + when Regexp + custom_proxies + when nil + TRUSTED_PROXIES + else + Regexp.union(TRUSTED_PROXIES, custom_proxies) + end + end + + def call(env) + env["action_dispatch.remote_ip"] = GetIp.new(env, self) + @app.call(env) + end + + class GetIp + + # IP v4 and v6 (with compression) validation regexp + # https://gist.github.com/1289635 + VALID_IP = %r{ + (^(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[0-9]{1,2})(\.(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[0-9]{1,2})){3}$) | # ip v4 + (^( + (([0-9A-Fa-f]{1,4}:){7}[0-9A-Fa-f]{1,4}) | # ip v6 not abbreviated + (([0-9A-Fa-f]{1,4}:){6}:[0-9A-Fa-f]{1,4}) | # ip v6 with double colon in the end + (([0-9A-Fa-f]{1,4}:){5}:([0-9A-Fa-f]{1,4}:)?[0-9A-Fa-f]{1,4}) | # - ip addresses v6 + (([0-9A-Fa-f]{1,4}:){4}:([0-9A-Fa-f]{1,4}:){0,2}[0-9A-Fa-f]{1,4}) | # - with + (([0-9A-Fa-f]{1,4}:){3}:([0-9A-Fa-f]{1,4}:){0,3}[0-9A-Fa-f]{1,4}) | # - double colon + (([0-9A-Fa-f]{1,4}:){2}:([0-9A-Fa-f]{1,4}:){0,4}[0-9A-Fa-f]{1,4}) | # - in the middle + (([0-9A-Fa-f]{1,4}:){6} ((\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)\.){3} (\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)) | # ip v6 with compatible to v4 + (([0-9A-Fa-f]{1,4}:){1,5}:((\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)\.){3}(\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)) | # ip v6 with compatible to v4 + (([0-9A-Fa-f]{1,4}:){1}:([0-9A-Fa-f]{1,4}:){0,4}((\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)\.){3}(\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)) | # ip v6 with compatible to v4 + (([0-9A-Fa-f]{1,4}:){0,2}:([0-9A-Fa-f]{1,4}:){0,3}((\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)\.){3}(\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)) | # ip v6 with compatible to v4 + (([0-9A-Fa-f]{1,4}:){0,3}:([0-9A-Fa-f]{1,4}:){0,2}((\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)\.){3}(\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)) | # ip v6 with compatible to v4 + (([0-9A-Fa-f]{1,4}:){0,4}:([0-9A-Fa-f]{1,4}:){1}((\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)\.){3}(\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)) | # ip v6 with compatible to v4 + (::([0-9A-Fa-f]{1,4}:){0,5}((\b((25[0-5])|(1\d{2})|(2[0-4]\d) |(\d{1,2}))\b)\.){3}(\b((25[0-5])|(1\d{2})|(2[0-4]\d)|(\d{1,2}))\b)) | # ip v6 with compatible to v4 + ([0-9A-Fa-f]{1,4}::([0-9A-Fa-f]{1,4}:){0,5}[0-9A-Fa-f]{1,4}) | # ip v6 with compatible to v4 + (::([0-9A-Fa-f]{1,4}:){0,6}[0-9A-Fa-f]{1,4}) | # ip v6 with double colon at the begining + (([0-9A-Fa-f]{1,4}:){1,7}:) # ip v6 without ending + )$) + }x + + def initialize(env, middleware) + @env = env + @middleware = middleware + @calculated_ip = false end - def remote_addrs - @remote_addrs ||= begin - list = @env['REMOTE_ADDR'] ? @env['REMOTE_ADDR'].split(/[,\s]+/) : [] - list.reject { |addr| addr =~ @trusted_proxies } + # 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 first address which is in this list + # if it's not a known proxy will be the originating IP. + # Format of HTTP_X_FORWARDED_FOR: + # client_ip, proxy_ip1, proxy_ip2... + # http://en.wikipedia.org/wiki/X-Forwarded-For + def calculate_ip + client_ip = @env['HTTP_CLIENT_IP'] + forwarded_ip = ips_from('HTTP_X_FORWARDED_FOR').first + remote_addrs = ips_from('REMOTE_ADDR') + + check_ip = client_ip && @middleware.check_ip + if check_ip && forwarded_ip != 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 + + client_ips = remove_proxies [client_ip, forwarded_ip, remote_addrs].flatten + if client_ips.present? + client_ips.first + else + # If there is no client ip we can return first valid proxy ip from REMOTE_ADDR + remote_addrs.find { |ip| valid_ip? ip } end end def to_s - return remote_addrs.first if remote_addrs.any? - - forwarded_ips = @env['HTTP_X_FORWARDED_FOR'] ? @env['HTTP_X_FORWARDED_FOR'].strip.split(/[,\s]+/) : [] - - if client_ip = @env['HTTP_CLIENT_IP'] - if @check_ip_spoofing && !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 - return client_ip - end + return @ip if @calculated_ip + @calculated_ip = true + @ip = calculate_ip + end - return forwarded_ips.reject { |ip| ip =~ @trusted_proxies }.last || @env["REMOTE_ADDR"] + private + + def ips_from(header) + @env[header] ? @env[header].strip.split(/[,\s]+/) : [] end - end - def initialize(app, check_ip_spoofing = true, trusted_proxies = nil) - @app = app - @check_ip_spoofing = check_ip_spoofing - regex = '(^127\.0\.0\.1$|^(10|172\.(1[6-9]|2[0-9]|30|31)|192\.168)\.)' - regex << "|(#{trusted_proxies})" if trusted_proxies - @trusted_proxies = Regexp.new(regex, "i") - end + def valid_ip?(ip) + ip =~ VALID_IP + end + + def not_a_proxy?(ip) + ip !~ @middleware.proxies + end + + def remove_proxies(ips) + ips.select { |ip| valid_ip?(ip) && not_a_proxy?(ip) } + end - def call(env) - env["action_dispatch.remote_ip"] = RemoteIpGetter.new(env, @check_ip_spoofing, @trusted_proxies) - @app.call(env) end + end -end
\ No newline at end of file +end |