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<div style="font-size: 13.3333px;">Hi,</div>
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<div style="font-size: 13.3333px;">Please see the following article regarding the risks of using MD5.</div>
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<a href="http://searchsecurity.techtarget.com/news/4500270165/MD5-vulnerability-renews-calls-for-faster-SHA-256-transition" target="_blank" style="color: rgb(17, 85, 204);">http://searchsecurity.<wbr>techtarget.com/news/<wbr>4500270165/MD5-vulnerability-<wbr>renews-calls-for-faster-SHA-<wbr>256-transition</a></div>
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<div style="font-size: 13.3333px;">Thanks,</div>
<div style="font-size: 13.3333px;">Xing</div>
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<div id="divRpF748807" style="direction: ltr;"><font face="Tahoma" size="2" color="#000000"><b>From:</b> yuliyang@cmss.chinamobile.com [yuliyang@cmss.chinamobile.com]<br>
<b>Sent:</b> Tuesday, April 11, 2017 3:52 AM<br>
<b>To:</b> openstack<br>
<b>Subject:</b> [Openstack] [Cinder-backup]why use sha256 instead md5 in chunk based backup-driver<br>
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<div><span></span>hi,all</div>
<div> why we use sha256 instead md5 in chunk based backup-driver , in the current file chunkeddriver.py, we have <span style="font-size:10.5pt; line-height:1.5">object_sha256['sha256s'] list to store all the sha256 value of</span><span style="line-height:1.5"> </span><span style="orphans:2; widows:2; line-height:1.5">sha_block_size
data , why we do not use md5 ,md5 is faster compute than sha256,and we all use the md5 value in </span><span style="font-size:10.5pt; line-height:1.5">_backup_chunk too, so we just need to compute one time and used in two diffrent place,it save much time</span></div>
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<div>yuliyang@cmss.chinamobile.com</div>
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