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11<H1 align="left">SVC_CalcSHA1 <IMG src="../image/BPT.gif" align="middle"><IMG src="../image/TWL.gif" align="middle"></H1>
12<H2>Syntax</H2>
13<DL>
14  <DD>
15  <PRE><CODE>#include &lt;twl/os/common/systemCall.h&gt;</CODE></PRE>
16  <PRE><CODE>void SVC_CalcSHA1( void* md,
17                    const void* data,
18                    unsigned int len );</CODE></PRE>
19</DL>
20<H2>Arguments</H2>
21<TABLE border="1">
22  <TBODY>
23    <TR>
24      <TD><B><I>md</I></B></TD>
25      <TD>Pointer to the memory location that holds the calculated SHA-1 value.</TD>
26    </TR>
27    <TR>
28      <TD><B><I>data</I></B></TD>
29      <TD>Pointer to the input data.</TD>
30    </TR>
31    <TR>
32      <TD><B><I>len</I></B></TD>
33      <TD>Size of the input data.</TD>
34    </TR>
35  </TBODY>
36</TABLE>
37<H2>Return Values</H2>
38<P>None.</P>
39<H2>Description</H2>
40<P>Performs the SHA-1 calculations.</P>
41<P>This is a utility function that successively calls the <CODE><A href="SVC_SHA1Init.html">SVC_SHA1Init()</A></CODE>, <CODE><A href="SVC_SHA1Update.html">SVC_SHA1Update()</A></CODE>, and <CODE><A href="SVC_SHA1GetHash.html">SVC_SHA1GetHash()</A></CODE> functions. Internally, the <CODE><A href="SVC_SHA1Init.html">SVCSHA1Context</A></CODE> structure is allocated to the stack, so make sure you have sufficient stack space when calling the function.</P>
42<P>The length of the generated SHA-1 value is 160 bits, or <CODE>SVC_SHA1_DIGEST_SIZE</CODE> (= 20) bytes. Use the <B><I>md</I></B> argument to pass an area that can store a value of this size.</P>
43<P>Specify the input data using <B><I>data</I></B> and <B><I>len</I></B>. Any size and alignment position can be used.</P>
44<P>SHA-1 is an algorithm to find the message digest value. For details, see RFC (Request For Comments) 3174, which is published by IETF (the Internet Engineering Task Force).</P>
45<H2>See Also</H2>
46<P><A href="SVC_SHA1Init.html"><CODE>SVC_SHA1Init</CODE></A><CODE>, <A href="SVC_SHA1Update.html">SVC_SHA1Update</A>, <A href="SVC_SHA1GetHash.html">SVC_SHA1GetHash</A></CODE></P>
47<H2>Revision History</H2>
48<P>2007/10/19 Initial version.</P>
49<hr><p>CONFIDENTIAL</p></body>
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