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POCan two different BASE 64 encoded strings result into same string if decoded?
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  1. POCan two different BASE 64 encoded strings result into same string if decoded?
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    copied!<p>On client side I am doing an MD5 encryption of a string and then a BASE 64 encoding on the hash generated.</p> <p>This final encoded string is then used for comparison on server side.</p> <p>I was able to do this successfully for many test cases but it failed for the below one.</p> <p>String for MD5</p> <pre><code> 2679:07071960:09348448:3:08912206:3:EXPRESS:1:EU4NW31E7INEC1X </code></pre> <p>My MD5 hash string:</p> <pre><code> 291423A531148527A9524EA0924CDF68 </code></pre> <p>My Base64 encoded string:</p> <pre><code> KRQjpTEUhSepUk6gkkzfaA== </code></pre> <p>When I try to put the MD5 hash string for BASE64 encoding on <a href="http://www.opinionatedgeek.com/dotnet/tools/base64encode/" rel="noreferrer">http://www.opinionatedgeek.com/dotnet/tools/base64encode/</a> it generates following string:</p> <pre><code> MjkxNDIzQTUzMTE0ODUyN0E5NTI0RUEwOTI0Q0RGNjg= </code></pre> <p>But, when I try to decode my Base64 string, that is "KRQjpTEUhSepUk6gkkzfaA==", here <a href="http://www.opinionatedgeek.com/dotnet/tools/Base64Decode/Default.aspx" rel="noreferrer">http://www.opinionatedgeek.com/dotnet/tools/Base64Decode/Default.aspx</a> I am getting my Hash Code(opened the .bin file being generated in hex editor).</p> <p>So, is it possible that a single string may have multiple Base64 encoded value?</p> <p>I am using the below code for generating the encoded string:</p> <pre><code> public static String getHashCode(String text) { MessageDigest md; byte[] md5hash = new byte[32]; try{ md = MessageDigest.getInstance("MD5"); md.update(text.getBytes("iso-8859-1"), 0, text.length()); md5hash = md.digest(); } catch(Exception e) { return "-1"; } String encoded = Base64.encode(md5hash); String retValue = new String(encoded); return retValue; } </code></pre> <p>Kindly, suggest what is going wrong and how to make sure that we use same digest both on client and server side.</p>
 

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