Date: 27 Sep 2005 11:33:52 -0000 From: "PRAMENDRA SINGH" <parma_it@rediffmail.com> Subject: [users:00128] Change in Script in Tunnel Conformace Testing To: contact@tahi.org Cc: users@tahi.org Message-Id: <20050927113352.9973.qmail@webmail53.rediffmail.com> X-Mail-Count: 00128Hi, I am Pramendra Singh. I am working on IPv6 implementation for MVL_=3.1, which is a RTOS by SAMSUNG with Linux kernel 2.4.20. I am worki=ng on TUNNEL module. For testing (conformance testing for ipv6-over-ipv4 =tunnel, RFC 2893),I am using FREE-BSD 5.4 as Tester Node and TAHI tool (v6e=val 3.0) as testing tool. While testing I face some problem and I felt= that this is due to the problems in script. So, I modified accordingly.= Here are the datils of changes made by me: 1.In fragment.seq = %ret=vRecv($IF1,5,0,0,v6overv4_echo_request_LINK1_nut2tn_1300, v6overv=4_echo_request_LINK1_nut2tn_1300_DF); /* I CHANGED UPPER LINE TO THE N=EXT LINE */ %ret=vRecv($IF1,5,0,0,v6overv4_echo_request_LINK1_nut2tn=_1300_DF, v6overv4_echo_request_LINK1_nut2tn_1300); CLARIFICATION: whe=n TN is sending a packet to NUT on link0 with packet length 1280,NUT is rep=lying on Link1 with a packet of length 1300 with DF bit SET. But origional =script was recognizing it as a packet with length 1300 with DF bit NOTSET. =After changing the script, script is getting the packet correctally. 2=.In fragment.def // // ICMPv4 Packet Too Big message // FEM_i=cmp4_destination_unreachable ( icmp4_packet_too_big_LINK1_tn2nut_MTU_142=0, _HETHER_tn2nut, { DF=1; _SRC(V4_OFFLINK_ADDRESS); _=DST(NUT_LINK1_V4_ADDRESS); }, { Code=4; Unused=1420; = payload=v4_orignal_packet_1450;/* I CHANGED HERE*/ = /* I CHANGED UPPER LINE TO THE THIS LINE */ pa=yload=v6overv4_orignal_packet_1500; } ) = CLARIFICATION: In the origional script when TN is sending a "Too Big"= message with MTU 1420 to NUT on Link1, it sending it with the wrong Source= Address and NUT was not able to change its MTU. But, further in the test =TN is again sending a "Too Big" message with MTU 1300 to NUT on Link1, and =this time NUT MTU was being changed successfully.The only difference in bot=h packets was the payload and value of the variable "unused" in the packet =definition. So, I just changed the payload to same one like it was in the "=Too Big" message with MTU 1300 and kept the variable's value unchanged. A=fter making the change NUT MTU was being changed successfully and my test g=ot passed. [ I gave prink statment in net/ipv4/route.c file in ip_rt_f=rag_needed() function and tried to find the reason for why NUT MTU was not =being changed when TN is sending a "Too Big" message with MTU 1420 to NUT o=n Link1. I find that the condition "rth->rt_src == iph->saddr" (line= no 1071) was not being met and so it was not getting in the code and NUT M=TU was not being changed. But when TN is sending a "Too Big" message with M=TU 1300 to NUT on Link1. I find that the condition "rth->rt_src == =iph->saddr" was being met and so it was getting in the code and NUT MTU was= being changed successfully.] please check it whether changes made by =me are correct or not and at the same time wheter they are fulfilling th=e test conditions correctally or not?? Thanks Pramendra Singh S=oftware Engineer, Larson & Toubro Infotech Church Street -2, Bangalore-=2 India - 560001128_2.html (attatchment)(tag is disabled)