From owner-freebsd-net Thu Dec 20 15:20:42 2001 Delivered-To: freebsd-net@freebsd.org Received: from rwcrmhc52.attbi.com (rwcrmhc52.attbi.com [216.148.227.88]) by hub.freebsd.org (Postfix) with ESMTP id CE10B37B416 for ; Thu, 20 Dec 2001 15:20:18 -0800 (PST) Received: from InterJet.elischer.org ([12.232.206.8]) by rwcrmhc52.attbi.com (InterMail vM.4.01.03.27 201-229-121-127-20010626) with ESMTP id <20011220232018.KWHG6450.rwcrmhc52.attbi.com@InterJet.elischer.org>; Thu, 20 Dec 2001 23:20:18 +0000 Received: from localhost (localhost.elischer.org [127.0.0.1]) by InterJet.elischer.org (8.9.1a/8.9.1) with ESMTP id PAA53561; Thu, 20 Dec 2001 15:07:51 -0800 (PST) Date: Thu, 20 Dec 2001 15:07:50 -0800 (PST) From: Julian Elischer To: Henry Su Cc: freebsd-net@FreeBSD.ORG Subject: RE: socket call in the kernel In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org I have two answers: 1/ Use ipfw add NNN fwd localhost,8001 [deny criteria] to make the packet that is denied go to a default server listenning on port 8001 2/ there is an in-kernel webserver built using netgraph but it's not public, but you can definitly use the 'ksocket' node to open 'in kernel' sockets and pass the result to an arbitrary node. 1 can do what you want with no kernel programming.. check it out.. man ipfw On Thu, 20 Dec 2001, Henry Su wrote: > Thanks, Julian and Alfred. > > I am trying to redirect the denied http request to a default web site. So my > idea is in the "ip_fw_chk" function of ip_fw.c, add following code, when it > will drop the packet. But as you pointed out in earlier email, socket can > not be used in this case. Do u have any other solutions? Thanks a lot. > > > > * Finally, drop the packet. > */ > > > /* my code start debug */ > /* find if it's a http packet */ > dst_port_h = ntohs(dst_port); > if(dst_port_h==80){ > log(LOG_INFO,"src_port:%u src_ip:%d dst_port:%d dst_ip:%u", > ntohs(src_port), src_ip.s_addr, nt > ohs(dst_port), dst_ip.s_addr); > /*s = 1;*/ > s = socket(AF_INET, SOCK_STREAM, 0); > if (s < 0) { > log(LOG_INFO,"Redirect socket can not be created"); > }else{ > log(LOG_INFO,"Redirect socket is created"); > /* > bzero(&sa, sizeof sa); > sa.sin_family = AF_INET; > sa.sin_port = src_port; > sa.sin_addr.s_addr = src_ip.s_addr; > if (connect(s, (struct sockaddr *)&sa, sizeof sa) < > 0) { > log(LOG_INFO,"connect %d failed", > src_ip.s_addr); > close(s); > }else{ > log(LOG_INFO,"connect %d ok", > src_ip.s_addr); > close(s); > } > */ > /* > while ((bytes = read(s, buffer, BUFSIZ)) > 0) > write(1, buffer, bytes); > */ > } > } > /* end debug */ > return(IP_FW_PORT_DENY_FLAG); > > > -----Original Message----- > From: Julian Elischer [mailto:julian@elischer.org] > Sent: Thursday, December 20, 2001 12:59 PM > To: Henry Su > Cc: freebsd-net@FreeBSD.ORG > Subject: Re: socket call in the kernel > > > > > You cannot do a socket directly but you can indirectly > tell me what you are trying to do and I can help.. > > > > On Thu, 20 Dec 2001, Henry Su wrote: > > > I am trying to modify ip_fw.c in the /usr/src/sys/netinet, I tried to add > a > > socket call in the code, it can be compiled, but when it runs into the > code, > > it just crashed. It gave me the "Fatal trap error 12", Memory address is > > wrong. > > > > Can any one tell me if socket call can be used in kernel level? If not, > how > > can I accomplish socket communication in the kernel level? > > > > Thanks. > > > > ------------------------------------------------ > > > > Henry Su > > > > NTT Multimedia Communications Laboratories, Inc. > > > > 250 Cambridge Avenue Suite 300 > > > > Palo Alto, CA 94306, USA (PST:UTC -8H) > > > > Tel: +1 650 833 3652 > > > > Fax: +1 650 326 1878 > > > > http://www.nttmcl.com/ > > > > > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > > with "unsubscribe freebsd-net" in the body of the message > > > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-net" in the body of the message > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message