HTTP::Request, added remote ip and peer_addr

spec/std/http/request_spec.cr

@@ -1,5 +1,6 @@
 require "spec"
 require "http/request"
+require "socket"
 
 module HTTP
   describe Request do
@@ -203,5 +204,69 @@ module HTTP
         io.to_s.should eq("GET /api/v3/some/resource?q=isearchforsomething&locale=de HTTP/1.1\r\n\r\n")
       end
     end
+
+    describe "#peer_addr=" do
+      it "sets the peer_addr" do
+        request = Request.from_io(StringIO.new("GET / HTTP/1.1\r\nHost: host.example.org\r\n\r\n")).not_nil!
+        addr = Socket::Addr.new("AF_INET", "12345", "127.0.0.1")
+        request.peer_addr = addr
+        request.peer_addr.should eq addr
+      end
+    end
+
+    describe "#peer_addr" do
+      it "returns the peer_addr" do
+        request = Request.from_io(StringIO.new("GET / HTTP/1.1\r\nHost: host.example.org\r\n\r\n")).not_nil!
+        addr = Socket::Addr.new("AF_INET", "12345", "127.0.0.1")
+        request.peer_addr = addr
+        request.peer_addr.should eq addr
+      end
+
+      it "raises if peer_addr is nil" do
+        request = Request.from_io(StringIO.new("GET / HTTP/1.1\r\nHost: host.example.org\r\n\r\n")).not_nil!
+
+        expect_raises do
+          request.peer_addr
+        end
+      end
+    end
+
+    describe "#remote_ip" do
+      context "trusting headers" do
+        it "returns the remote ip from the Client-Ip" do
+          request = Request.from_io(StringIO.new("GET / HTTP/1.1\r\nHost: host.example.org\r\nClient-Ip: 8.8.8.8\r\n\r\n")).not_nil!
+          addr    = Socket::Addr.new("AF_INET", "12345", "127.0.0.1")
+          request.peer_addr = addr
+
+          request.remote_ip.should eq "8.8.8.8"
+        end
+
+        it "returns the remote ip from the X-Forwarded-For header" do
+          request = Request.from_io(StringIO.new("GET / HTTP/1.1\r\nHost: host.example.org\r\nX-Forwarded-For: 4.4.4.4, 10.0.0.1\r\n\r\n")).not_nil!
+          addr    = Socket::Addr.new("AF_INET", "12345", "127.0.0.1")
+          request.peer_addr = addr
+
+          request.remote_ip.should eq "4.4.4.4"
+        end
+
+        it "returns the peer addr if headers are not set" do
+          request = Request.from_io(StringIO.new("GET / HTTP/1.1\r\nHost: host.example.org\r\n\r\n")).not_nil!
+          addr    = Socket::Addr.new("AF_INET", "12345", "127.0.0.1")
+          request.peer_addr = addr
+
+          request.remote_ip.should eq "127.0.0.1"
+        end
+      end
+
+      context "without trusting headers" do
+        it "returns the peer_addr ip address" do
+          request = Request.from_io(StringIO.new("GET / HTTP/1.1\r\nHost: host.example.org\r\n\r\n")).not_nil!
+          addr = Socket::Addr.new("AF_INET", "12345", "127.0.0.1")
+          request.peer_addr = addr
+
+          request.remote_ip(false).should eq "127.0.0.1"
+        end
+      end
+    end
   end
 end

src/http/request.cr

@@ -33,6 +33,27 @@ class HTTP::Request
     @method == "HEAD"
   end
 
+  def peer_addr=(addr)
+    @peer_addr = addr
+  end
+
+  def peer_addr
+    @peer_addr.not_nil!
+  end
+
+  def remote_ip(trust_headers=true)
+    if trust_headers
+      client_ips = ips_from("Client-Ip").reverse
+      forwarded_ips = ips_from("X-Forwarded-For").reverse
+
+      ips = [forwarded_ips, client_ips, peer_addr.ip_address].flatten.compact
+
+      first_remote_ip_address(ips) || peer_addr.ip_address
+    else
+      peer_addr.ip_address
+    end
+  end
+
   def to_io(io)
     io << @method << " " << resource << " " << @version << "\r\n"
     cookies = @cookies
@@ -68,4 +89,21 @@ class HTTP::Request
   private def uri
     (@uri ||= URI.parse(@resource)).not_nil!
   end
+
+  private def ips_from(header)
+    if ips = headers[header]? || headers["Http-#{header.tr("_", "-")}"]?
+      ips.strip.split(/[,\s]+/)
+    else
+      [] of String
+    end
+  end
+
+  private def first_remote_ip_address(ip_addresses)
+    ip_addresses.find { |ip| !trusted_proxy?(ip) }
+  end
+
+  private def trusted_proxy?(ip)
+    ip =~ /\A127\.0\.0\.1\Z|\A(10|172\.(1[6-9]|2[0-9]|30|31)|192\.168)\.|\A::1\Z|\Afd[0-9a-f]{2}:.+|\Alocalhost\Z|\Aunix\Z|\Aunix:/i
+  end
+
 end

src/http/server/server.cr

@@ -139,6 +139,8 @@ class HTTP::Server
           return
         end
         break unless request
+        request.peer_addr = sock.peeraddr
+
         response = @handler.call(request)
         response.headers["Connection"] = "keep-alive" if request.keep_alive?
         response.to_io io