Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site bu-cs.UUCP Path: utzoo!linus!philabs!cmcl2!seismo!harvard!bu-cs!root From: root@bu-cs.UUCP (Barry Shein) Newsgroups: net.lan Subject: Re: TFTP between IBM-PC, 4.2, Wollongong.. Message-ID: <214@bu-cs.UUCP> Date: Wed, 6-Mar-85 14:25:25 EST Article-I.D.: bu-cs.214 Posted: Wed Mar 6 14:25:25 1985 Date-Received: Sat, 9-Mar-85 20:02:56 EST References: <136@cernvax.UUCP> Organization: Boston Univ Comp. Sci. Lines: 27 There was in fact a fix to udp_usrreq.c checksum in 4.2, if you have a recent release of TWG TCP/IP it should incorporate this fix and hence your TWG<->4.2 UDP *should* be broken. Here is a diff file: (cd /usr/sys/netinet;diff udp_usrreq.c udp_usrreq.orig.c) 2d1 < /* modified 11/13/84 Boston University bug in checksum */ 35c34 < int udpcksum = 0; /* 11/13/84 */ --- > int udpcksum; 189c188 < ui->ui_len = htons((u_short)(len+sizeof(struct udphdr)));/* 11/13/84 */ --- > ui->ui_len = len + sizeof (struct udphdr); 194c193 < ui->ui_ulen = (u_short)ui->ui_len; /* 11/13/84 */ --- > ui->ui_ulen = htons((u_short)ui->ui_len); pretty simple, check with TWG about getting a release of their fix if you don't have it already. -Barry Shein, Boston University