From owner-freebsd-bugs@freebsd.org Fri Jan 5 02:08:20 2018 Return-Path: Delivered-To: freebsd-bugs@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id B0A5EEA6892 for ; Fri, 5 Jan 2018 02:08:20 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2001:1900:2254:206a::16:76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 9C6876D906 for ; Fri, 5 Jan 2018 02:08:20 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id w0528KIQ060599 for ; Fri, 5 Jan 2018 02:08:20 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id w0528KKE060598 for freebsd-bugs@FreeBSD.org; Fri, 5 Jan 2018 02:08:20 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 224920] limited broadcast for Linux programs Date: Fri, 05 Jan 2018 02:08:20 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: 11.1-STABLE X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: henry.hu.sh@gmail.com X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: freebsd-bugs@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 05 Jan 2018 02:08:20 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D224920 Bug ID: 224920 Summary: limited broadcast for Linux programs Product: Base System Version: 11.1-STABLE Hardware: Any OS: Any Status: New Severity: Affects Only Me Priority: --- Component: kern Assignee: freebsd-bugs@FreeBSD.org Reporter: henry.hu.sh@gmail.com Limited broadcast, or sending to 255.255.255.255, is the behavior specified= in RFC 947, which is deprecated (https://wiki.freebsd.org/NetworkRFCCompliance= ). As a result, FreeBSD does not support it (sending to 255.255.255.255 result= s in an ether address of the default gw), unless IP_ONESBCAST is specified. However, for Linux programs, it seems to be still expected to work. Some programs send UDP packets to 255.255.255.255 to discover devices on local network. One such example is Canon's ScanGear MP program, which uses this w= ay to discover local scanners. Sample trace: 21:06:37.887917 b0:6e:bf:2a:e7:23 > 04:a1:51:15:5e:11, ethertype IPv4 (0x08= 00), length 166: 192.168.1.126.51201 > 255.255.255.255.161: C=3D"canon_admin" GetRequest(104) .1.3.6.1.4.1.1602.1.3.1.13.0 .1.3.6.1.4.1.1602.1.2.1.8.1.3= .1.1 .1.3.6.1.4.1.1602.1.1.1.1.0 .1.3.6.1.4.1.1602.1.1.1.10.0 .1.3.6.1.4.1.1602.1.3.1.12.0 Expected: 21:05:46.430205 b0:6e:bf:2a:e7:23 > ff:ff:ff:ff:ff:ff, ethertype IPv4 (0x08= 00), length 166: 192.168.1.126.44951 > 255.255.255.255.161: C=3D"canon_admin" GetRequest(104) .1.3.6.1.4.1.1602.1.3.1.13.0 .1.3.6.1.4.1.1602.1.2.1.8.1.3= .1.1 .1.3.6.1.4.1.1602.1.1.1.1.0 .1.3.6.1.4.1.1602.1.1.1.10.0 .1.3.6.1.4.1.1602.1.3.1.12.0 Since FreeBSD does not support this, this program cannot discover any devic= es. The discovery code is in some binary blob, which is unable to be changed. F= or a closer emulation of Linux behavior, I suggest that when running Linux progr= ams, we send a broadcast packet to the interface of the default route. A workaround is letting ipfw do a forward: fwd 192.168.1.255 udp from me to 255.255.255.255 --=20 You are receiving this mail because: You are the assignee for the bug.=