netdev - [iproute2] tc pedit modify ethhdr ?

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 24 Mar 2010 05:31:47 -0700 (PDT)
From:	Xiaofei Wu <xiaofei_wu08@...oo.com>
To:	stephen.hemminger@...tta.com
Cc:	hadi <hadi@...erus.ca>, linux netdev <netdev@...r.kernel.org>
Subject: [iproute2]  tc pedit   modify  ethhdr ?

Hi all,

I want to modify  a packet's   h_dest and h_source in  structethhdr { } .

in   tc / m_pedit.c
------

36 explain(void)
37 {
38         fprintf(stderr, "Usage: ... pedit munge <MUNGE>\n");
39         fprintf(stderr,
40                 "Where: MUNGE := <RAW>|<LAYERED>\n"
41                 "\t<RAW>:= <OFFSETC>[ATC]<CMD>\n "
42                 "\t\tOFFSETC:= offset <offval> <u8|u16|u32>\n "
43                 "\t\tATC:= at <atval> offmask <maskval> shift <shiftval>\n "
44                 "\t\tNOTE: offval is byte offset, must be multiple of 4\n "
45                 "\t\tNOTE: maskval is a 32 bit hex number\n "
46                 "\t\tNOTE: shiftval is a is a shift value\n "
47                 "\t\tCMD:= clear | invert | set <setval>| retain\n "
48                 "\t<LAYERED>:= ip <ipdata> | ip6 <ip6data> \n "
49                 " \t\t| udp <udpdata> | tcp <tcpdata> | icmp <icmpdata> \n"
50                 "For Example usage look at the examples directory\n");
51 
52 }
------

OFFSETC:= offset <offval> <u8|u16|u32>
NOTE: offval is byte offset, must be multiple of 4

but the size of ethhdr is 14 bytes, 14 is not multiple of 4 .
How to use 'tc ... pedit ...'  modify  a packet's   h_dest and h_source 
of ethhdr ?
Use ' ... pedit munge offset -14 u16 set 0x0090 munge offset -12 u32 set 0x9600030a ... '   or 
use ' ... pedit munge offset -16 u32 ... munge offset -12  ... '  ?


--
Wu


      

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html