/*
 * Mausezahn - A fast versatile traffic generator
 * Copyright (C) 2008-2010 Herbert Haas
 * 
 * This program is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License version 2 as published by the 
 * Free Software Foundation.
 * 
 * This program is distributed in the hope that it will be useful, but WITHOUT 
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more 
 * details.
 * 
 * You should have received a copy of the GNU General Public License along with 
 * this program; if not, see http://www.gnu.org/licenses/gpl-2.0.html
 * 
*/

#include "mz.h"
#include "mops.h"




// -- TOC: --
//
// u_int16_t      mops_sum16                  (u_int16_t len, u_int8_t buff[])
// int            mops_get_transport_sum      (struct mops *mp)


//////////////////////////////////////////////////////////////////////////////////
//
//  See also:
//  
//  RFC1071 - Computing the Internet checksum
//  
//////////////////////////////////////////////////////////////////////////////////



// Generic 16-bit checksum code as required for IP and other headers.
// The checksum is calculated over buff[] which is of length len. 
//
// RETURN VALUE: The checksum! (Validated - correct!!!)
// 
// Example:  t16 = mops_sum16 (20, &mp->frame[fp]);
// 
u_int16_t mops_sum16 (u_int16_t len, u_int8_t buff[])
{
   
   u_int16_t word16;
   u_int32_t sum=0;
   u_int16_t i;
       
   // make 16 bit words out of every two adjacent 8 bit words in the packet and add them up
   for (i=0; i<len; i=i+2)
     {
	word16 =((buff[i]<<8)&0xFF00)+buff[i+1];
	sum = sum + (u_int32_t) word16;
     }
   
   // take only 16 bits out of the 32 bit sum and add up the carries
   while (sum>>16)
     sum = (sum & 0xFFFF)+(sum >> 16);
   
   // one's complement the result
   sum = ~sum;
   
   return ((u_int16_t) sum);
}





// sets UDP or TCP checksum within mp[]->frame
//   TODO: copying the whole segment is ugly and slow;
//         make it more efficient and realize it in-place.
//         
int mops_get_transport_sum(struct mops *mp)
{
   u_int8_t buf[MAX_PAYLOAD_SIZE];
   u_int16_t len;
   int udp_used;
   
   u_int16_t sum;
   
   udp_used = mp->use_UDP; // 0 or 1, 0 means TCP
   
   // IP Pseudoheader (12 Bytes)
   mops_hton4(&mp->ip_src, &buf[0]);
   mops_hton4(&mp->ip_dst, &buf[4]);
   buf[9]=0x00;

   
   // Copy segment
   if (udp_used) 
     {
	buf[10]=0x11; // proto UDP (17 dec)
	len = mp->udp_len;
	mops_hton2(&len, &buf[11]);
	memcpy(&buf[13], &mp->frame[mp->begin_UDP], len);
	// reset checksum to zero
	buf[19] = 0x00;
	buf[20] = 0x00;
	sum = mops_sum16(len+12, buf); 
	// insert checksum in UDP header (in frame)
	mops_hton2 (&sum, &mp->frame[(mp->begin_UDP)+7]);

     }
   else
     {
	buf[10]=0x06; // proto TCP
	len = mp->ip_len - mp->ip_IHL;
	mops_hton2((u_int16_t*)&len, &buf[11]);
	memcpy(&buf[13], &mp->frame[mp->begin_TCP], len);
	// reset checksum to zero
	buf[29] = 0x00;
	buf[30] = 0x00;
	sum = mops_sum16(len+12, buf);
	// insert checksum in TCP header (in frame)
	mops_hton2 (&sum, &mp->frame[(mp->begin_TCP)+17]);
     }
   
   
   return 0;
}

0920b9279821db244d1ca69'>Documentation</a>/<a href='/cgit.cgi/linux/net-next.git/commit/Documentation/i2c?h=nds-private-remove&amp;id=9af07af948ff3a8e20920b9279821db244d1ca69'>i2c</a>/<a href='/cgit.cgi/linux/net-next.git/commit/Documentation/i2c/fault-codes?h=nds-private-remove&amp;id=9af07af948ff3a8e20920b9279821db244d1ca69'>fault-codes</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='h' value='nds-private-remove'/><input type='hidden' name='id' value='9af07af948ff3a8e20920b9279821db244d1ca69'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Dave Airlie &lt;airlied@redhat.com&gt;</td><td class='right'>2016-07-27 10:33:08 +1000</td></tr>
<tr><th>committer</th><td>Dave Airlie &lt;airlied@redhat.com&gt;</td><td class='right'>2016-07-27 10:33:08 +1000</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/Documentation/i2c/fault-codes?h=nds-private-remove&amp;id=9af07af948ff3a8e20920b9279821db244d1ca69'>9af07af948ff3a8e20920b9279821db244d1ca69</a> (<a href='/cgit.cgi/linux/net-next.git/patch/Documentation/i2c/fault-codes?id=9af07af948ff3a8e20920b9279821db244d1ca69'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?h=nds-private-remove&amp;id=9af07af948ff3a8e20920b9279821db244d1ca69'>b208a39aa6b33a24f46cf2bd5cbbd623f2f68bfb</a> /<a href='/cgit.cgi/linux/net-next.git/tree/Documentation/i2c/fault-codes?h=nds-private-remove&amp;id=9af07af948ff3a8e20920b9279821db244d1ca69'>Documentation/i2c/fault-codes</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/Documentation/i2c/fault-codes?h=nds-private-remove&amp;id=5e580523d9128a4d8364fe89d36c38fc7819c8dd'>5e580523d9128a4d8364fe89d36c38fc7819c8dd</a> (<a href='/cgit.cgi/linux/net-next.git/diff/Documentation/i2c/fault-codes?h=nds-private-remove&amp;id=9af07af948ff3a8e20920b9279821db244d1ca69&amp;id2=5e580523d9128a4d8364fe89d36c38fc7819c8dd'>diff</a>)</td></tr><tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/Documentation/i2c/fault-codes?h=nds-private-remove&amp;id=e8d3ef02787fc72996cfb423180dc79764c239fa'>e8d3ef02787fc72996cfb423180dc79764c239fa</a> (<a href='/cgit.cgi/linux/net-next.git/diff/Documentation/i2c/fault-codes?h=nds-private-remove&amp;id=9af07af948ff3a8e20920b9279821db244d1ca69&amp;id2=e8d3ef02787fc72996cfb423180dc79764c239fa'>diff</a>)</td></tr></table>
<div class='commit-subject'>Merge tag 'topic/drm-misc-2016-07-22' of git://anongit.freedesktop.org/drm-intel into drm-next</div><div class='commit-msg'>Suddenly everyone shows up with their trivial patch series!
- piles of if (!ptr) check removals from Markus Elfring
- more of_node_put fixes from Peter Chen
- make fbdev support really optional in all drivers (except vmwgfx),
  somehow this fell through the cracks when we did all the hard prep work
  a while ago. Patches from Tobias Jakobi.
- leftover patches for the connector reg/unreg cleanup (required that I
  backmerged drm-next) from Chris
- last vgem fence patch from Chris
- fix up warnings in the new sphinx gpu docs build
- misc other small bits

* tag 'topic/drm-misc-2016-07-22' of git://anongit.freedesktop.org/drm-intel: (57 commits)
  GPU-DRM-Exynos: Delete an unnecessary check before the function call "vunmap"
  GPU-DRM-sun4i: Delete an unnecessary check before drm_fbdev_cma_hotplug_event()
  drm/atomic: Delete an unnecessary check before drm_property_unreference_blob()
  drm/rockchip: analogix_dp: add missing clk_disable_unprepare() on error
  drm: drm_connector-&gt;s/connector_id/index/ for consistency
  drm/virtio: Fix non static symbol warning
  drm/arc: Remove redundant dev_err call in arcpgu_load()
  drm/arc: Fix some sparse warnings
  drm/vgem: Fix non static symbol warning
  drm/doc: Spinx leftovers
  drm/dp-mst: Missing kernel doc
  drm/dp-mst: Remove tx_down_in_progress
  drm/doc: Fix missing kerneldoc for drm_dp_helper.c
  drm: Extract&amp;Document drm_irq.h
  drm/doc: document all the properties in drm_mode_config
  drm/drm-kms.rst: Remove unused drm_fourcc.h include directive
  drm/doc: Add kerneldoc for @index
  drm: Unexport drm_connector_unregister_all()
  drm/sun4i: Remove redundant call to drm_connector_unregister_all()
  drm/ttm: Delete an unnecessary check before the function call "ttm_tt_destroy"
  ...
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=9af07af948ff3a8e20920b9279821db244d1ca69'>Diffstat</a> (limited to 'Documentation/i2c/fault-codes')</div><table summary='diffstat' class='diffstat'>