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<div id="projectname">Platform Security Architecture — cryptography and keystore interface
&#160;<span id="projectnumber">beta 2 — 2019-02-22</span>
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<a href="#define-members">Macros</a> &#124;
<a href="#typedef-members">Typedefs</a> &#124;
<a href="#func-members">Functions</a> </div>
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<div class="title">Message authentication codes</div> </div>
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Macros</h2></td></tr>
<tr class="memitem:ga441b6efc161a4573d06465bd22d9dc2d"><td class="memItemLeft" align="right" valign="top">#define&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__MAC.html#ga441b6efc161a4573d06465bd22d9dc2d">PSA_MAC_OPERATION_INIT</a>&#160;&#160;&#160;{0}</td></tr>
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Typedefs</h2></td></tr>
<tr class="memitem:ga78f0838b0c4e3db28b26355624d4bd37"><td class="memItemLeft" align="right" valign="top">typedef struct psa_mac_operation_s&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a></td></tr>
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Functions</h2></td></tr>
<tr class="memitem:gace78d9b51394f9d4f77952963665897a"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__error.html#ga05676e70ba5c6a7565aff3c36677c1f9">psa_status_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__MAC.html#gace78d9b51394f9d4f77952963665897a">psa_mac_compute</a> (<a class="el" href="group__platform.html#gabf6d5fd4e2ea89ecd425c88f057e7f75">psa_key_handle_t</a> handle, <a class="el" href="group__crypto__types.html#gac2e4d47f1300d73c2f829a6d99252d69">psa_algorithm_t</a> alg, const uint8_t *input, size_t input_length, uint8_t *mac, size_t mac_size, size_t *mac_length)</td></tr>
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<tr class="memitem:ga08e2e8c21bfe762a907266f3bdd1d07c"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__error.html#ga05676e70ba5c6a7565aff3c36677c1f9">psa_status_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__MAC.html#ga08e2e8c21bfe762a907266f3bdd1d07c">psa_mac_verify</a> (<a class="el" href="group__platform.html#gabf6d5fd4e2ea89ecd425c88f057e7f75">psa_key_handle_t</a> handle, <a class="el" href="group__crypto__types.html#gac2e4d47f1300d73c2f829a6d99252d69">psa_algorithm_t</a> alg, const uint8_t *input, size_t input_length, const uint8_t *mac, const size_t mac_length)</td></tr>
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<tr class="memitem:gad33f2b15119593571ca6b8e7c757ab0e"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__error.html#ga05676e70ba5c6a7565aff3c36677c1f9">psa_status_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__MAC.html#gad33f2b15119593571ca6b8e7c757ab0e">psa_mac_sign_setup</a> (<a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a> *operation, <a class="el" href="group__platform.html#gabf6d5fd4e2ea89ecd425c88f057e7f75">psa_key_handle_t</a> handle, <a class="el" href="group__crypto__types.html#gac2e4d47f1300d73c2f829a6d99252d69">psa_algorithm_t</a> alg)</td></tr>
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<tr class="memitem:gaa721a59ae6d085ec90c7dc918879a027"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__error.html#ga05676e70ba5c6a7565aff3c36677c1f9">psa_status_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__MAC.html#gaa721a59ae6d085ec90c7dc918879a027">psa_mac_verify_setup</a> (<a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a> *operation, <a class="el" href="group__platform.html#gabf6d5fd4e2ea89ecd425c88f057e7f75">psa_key_handle_t</a> handle, <a class="el" href="group__crypto__types.html#gac2e4d47f1300d73c2f829a6d99252d69">psa_algorithm_t</a> alg)</td></tr>
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<tr class="memitem:ga5560af371497babefe03c9da4e8a1c05"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__error.html#ga05676e70ba5c6a7565aff3c36677c1f9">psa_status_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__MAC.html#ga5560af371497babefe03c9da4e8a1c05">psa_mac_update</a> (<a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a> *operation, const uint8_t *input, size_t input_length)</td></tr>
<tr class="separator:ga5560af371497babefe03c9da4e8a1c05"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:gac22bc0125580c96724a09226cfbc97f2"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__error.html#ga05676e70ba5c6a7565aff3c36677c1f9">psa_status_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__MAC.html#gac22bc0125580c96724a09226cfbc97f2">psa_mac_sign_finish</a> (<a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a> *operation, uint8_t *mac, size_t mac_size, size_t *mac_length)</td></tr>
<tr class="separator:gac22bc0125580c96724a09226cfbc97f2"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:gac92b2930d6728e1be4d011c05d485822"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__error.html#ga05676e70ba5c6a7565aff3c36677c1f9">psa_status_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__MAC.html#gac92b2930d6728e1be4d011c05d485822">psa_mac_verify_finish</a> (<a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a> *operation, const uint8_t *mac, size_t mac_length)</td></tr>
<tr class="separator:gac92b2930d6728e1be4d011c05d485822"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:gacd8dd54855ba1bc0a03f104f252884fd"><td class="memItemLeft" align="right" valign="top"><a class="el" href="group__error.html#ga05676e70ba5c6a7565aff3c36677c1f9">psa_status_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group__MAC.html#gacd8dd54855ba1bc0a03f104f252884fd">psa_mac_abort</a> (<a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a> *operation)</td></tr>
<tr class="separator:gacd8dd54855ba1bc0a03f104f252884fd"><td class="memSeparator" colspan="2">&#160;</td></tr>
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<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<h2 class="groupheader">Macro Definition Documentation</h2>
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<td class="memname">#define PSA_MAC_OPERATION_INIT&#160;&#160;&#160;{0}</td>
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<p>This macro returns a suitable initializer for a MAC operation object of type <a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a>. </p>
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<h2 class="groupheader">Typedef Documentation</h2>
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<td class="memname">typedef struct psa_mac_operation_s <a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a></td>
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<p>The type of the state data structure for multipart MAC operations.</p>
<p>Before calling any function on a MAC operation object, the application must initialize it by any of the following means:</p><ul>
<li>Set the structure to all-bits-zero, for example: <div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span>&#160;psa_mac_operation_t operation;</div><div class="line"><a name="l00002"></a><span class="lineno"> 2</span>&#160;memset(&amp;operation, 0, sizeof(operation));</div></div><!-- fragment --></li>
<li>Initialize the structure to logical zero values, for example: <div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span>&#160;psa_mac_operation_t operation = {0};</div></div><!-- fragment --></li>
<li>Initialize the structure to the initializer <a class="el" href="group__MAC.html#ga441b6efc161a4573d06465bd22d9dc2d">PSA_MAC_OPERATION_INIT</a>, for example: <div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span>&#160;psa_mac_operation_t operation = PSA_MAC_OPERATION_INIT;</div></div><!-- fragment --></li>
<li>Assign the result of the function psa_mac_operation_init() to the structure, for example: <div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span>&#160;psa_mac_operation_t operation;</div><div class="line"><a name="l00002"></a><span class="lineno"> 2</span>&#160;operation = psa_mac_operation_init();</div></div><!-- fragment --></li>
</ul>
<p>This is an implementation-defined <code>struct</code>. Applications should not make any assumptions about the content of this structure except as directed by the documentation of a specific implementation. </p>
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<h2 class="groupheader">Function Documentation</h2>
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<td class="memname"><a class="el" href="group__error.html#ga05676e70ba5c6a7565aff3c36677c1f9">psa_status_t</a> psa_mac_abort </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a> *&#160;</td>
<td class="paramname"><em>operation</em></td><td>)</td>
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<p>Abort a MAC operation.</p>
<p>Aborting an operation frees all associated resources except for the <code>operation</code> structure itself. Once aborted, the operation object can be reused for another operation by calling <a class="el" href="group__MAC.html#gad33f2b15119593571ca6b8e7c757ab0e">psa_mac_sign_setup()</a> or <a class="el" href="group__MAC.html#gaa721a59ae6d085ec90c7dc918879a027">psa_mac_verify_setup()</a> again.</p>
<p>You may call this function any time after the operation object has been initialized by any of the following methods:</p><ul>
<li>A call to <a class="el" href="group__MAC.html#gad33f2b15119593571ca6b8e7c757ab0e">psa_mac_sign_setup()</a> or <a class="el" href="group__MAC.html#gaa721a59ae6d085ec90c7dc918879a027">psa_mac_verify_setup()</a>, whether it succeeds or not.</li>
<li>Initializing the <code>struct</code> to all-bits-zero.</li>
<li>Initializing the <code>struct</code> to logical zeros, e.g. <code>psa_mac_operation_t operation = {0}</code>.</li>
</ul>
<p>In particular, calling <a class="el" href="group__MAC.html#gacd8dd54855ba1bc0a03f104f252884fd">psa_mac_abort()</a> after the operation has been terminated by a call to <a class="el" href="group__MAC.html#gacd8dd54855ba1bc0a03f104f252884fd">psa_mac_abort()</a>, <a class="el" href="group__MAC.html#gac22bc0125580c96724a09226cfbc97f2">psa_mac_sign_finish()</a> or <a class="el" href="group__MAC.html#gac92b2930d6728e1be4d011c05d485822">psa_mac_verify_finish()</a> is safe and has no effect.</p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">operation</td><td>Initialized MAC operation.</td></tr>
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</dd>
</dl>
<dl class="retval"><dt>Return values</dt><dd>
<table class="retval">
<tr><td class="paramname"><a class="el" href="group__error.html#ga4cc859e2c66ca381c7418db3527a65e1">PSA_SUCCESS</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga933d40fa2a591004f2e93aa91e11db84">PSA_ERROR_BAD_STATE</a></td><td><code>operation</code> is not an active MAC operation. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga5cdb6948371d49e916106249020ea3f7">PSA_ERROR_COMMUNICATION_FAILURE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga08b10e70fa5ff0b05c631d9f8f6b2c6b">PSA_ERROR_HARDWARE_FAILURE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga2c5dda1485cb54f2385cb9c1279a7004">PSA_ERROR_TAMPERING_DETECTED</a></td><td></td></tr>
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</dd>
</dl>
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<td class="memname"><a class="el" href="group__error.html#ga05676e70ba5c6a7565aff3c36677c1f9">psa_status_t</a> psa_mac_compute </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group__platform.html#gabf6d5fd4e2ea89ecd425c88f057e7f75">psa_key_handle_t</a>&#160;</td>
<td class="paramname"><em>handle</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group__crypto__types.html#gac2e4d47f1300d73c2f829a6d99252d69">psa_algorithm_t</a>&#160;</td>
<td class="paramname"><em>alg</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">const uint8_t *&#160;</td>
<td class="paramname"><em>input</em>, </td>
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<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">size_t&#160;</td>
<td class="paramname"><em>input_length</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">uint8_t *&#160;</td>
<td class="paramname"><em>mac</em>, </td>
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<td class="paramkey"></td>
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<td class="paramtype">size_t&#160;</td>
<td class="paramname"><em>mac_size</em>, </td>
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<td class="paramkey"></td>
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<td class="paramtype">size_t *&#160;</td>
<td class="paramname"><em>mac_length</em>&#160;</td>
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<td>)</td>
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<p>Calculate the MAC (message authentication code) of a message.</p>
<dl class="section note"><dt>Note</dt><dd>To verify the MAC of a message against an expected value, use <a class="el" href="group__MAC.html#ga08e2e8c21bfe762a907266f3bdd1d07c">psa_mac_verify()</a> instead. Beware that comparing integrity or authenticity data such as MAC values with a function such as <code>memcmp</code> is risky because the time taken by the comparison may leak information about the MAC value which could allow an attacker to guess a valid MAC and thereby bypass security controls.</dd></dl>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir"></td><td class="paramname">handle</td><td>Handle to the key to use for the operation. </td></tr>
<tr><td class="paramdir"></td><td class="paramname">alg</td><td>The MAC algorithm to compute (<code>PSA_ALG_XXX</code> value such that <a class="el" href="group__crypto__types.html#gaca7aee4c9dde316b3b1a150a26eab776">PSA_ALG_IS_MAC</a>(<code>alg</code>) is true). </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">input</td><td>Buffer containing the input message. </td></tr>
<tr><td class="paramdir"></td><td class="paramname">input_length</td><td>Size of the <code>input</code> buffer in bytes. </td></tr>
<tr><td class="paramdir">[out]</td><td class="paramname">mac</td><td>Buffer where the MAC value is to be written. </td></tr>
<tr><td class="paramdir"></td><td class="paramname">mac_size</td><td>Size of the <code>mac</code> buffer in bytes. </td></tr>
<tr><td class="paramdir">[out]</td><td class="paramname">mac_length</td><td>On success, the number of bytes that make up the MAC value.</td></tr>
</table>
</dd>
</dl>
<dl class="retval"><dt>Return values</dt><dd>
<table class="retval">
<tr><td class="paramname"><a class="el" href="group__error.html#ga4cc859e2c66ca381c7418db3527a65e1">PSA_SUCCESS</a></td><td>Success. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#gadf22718935657c2c3168c228204085f9">PSA_ERROR_INVALID_HANDLE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#gaba00e3e6ceb2b12965a81e5ac02ae040">PSA_ERROR_EMPTY_SLOT</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga4d1b8dd8526177a15a210b7afc1accb1">PSA_ERROR_NOT_PERMITTED</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga798df25a505ebf931f7bec1f80f1f85f">PSA_ERROR_INVALID_ARGUMENT</a></td><td><code>key</code> is not compatible with <code>alg</code>. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga1dcc6d130633ed5db8942257581b55dd">PSA_ERROR_NOT_SUPPORTED</a></td><td><code>alg</code> is not supported or is not a MAC algorithm. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga91b2ad8a867517a2651f1b076c5216e5">PSA_ERROR_INSUFFICIENT_MEMORY</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga5cdb6948371d49e916106249020ea3f7">PSA_ERROR_COMMUNICATION_FAILURE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga08b10e70fa5ff0b05c631d9f8f6b2c6b">PSA_ERROR_HARDWARE_FAILURE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga2c5dda1485cb54f2385cb9c1279a7004">PSA_ERROR_TAMPERING_DETECTED</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga933d40fa2a591004f2e93aa91e11db84">PSA_ERROR_BAD_STATE</a></td><td>The library has not been previously initialized by <a class="el" href="group__initialization.html#ga2de150803fc2f7dc6101d5af7e921dd9" title="Library initialization. ">psa_crypto_init()</a>. It is implementation-dependent whether a failure to initialize results in this error code. </td></tr>
</table>
</dd>
</dl>
</div>
</div>
<a class="anchor" id="gac22bc0125580c96724a09226cfbc97f2"></a>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname"><a class="el" href="group__error.html#ga05676e70ba5c6a7565aff3c36677c1f9">psa_status_t</a> psa_mac_sign_finish </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a> *&#160;</td>
<td class="paramname"><em>operation</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">uint8_t *&#160;</td>
<td class="paramname"><em>mac</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">size_t&#160;</td>
<td class="paramname"><em>mac_size</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">size_t *&#160;</td>
<td class="paramname"><em>mac_length</em>&#160;</td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div><div class="memdoc">
<p>Finish the calculation of the MAC of a message.</p>
<p>The application must call <a class="el" href="group__MAC.html#gad33f2b15119593571ca6b8e7c757ab0e">psa_mac_sign_setup()</a> before calling this function. This function calculates the MAC of the message formed by concatenating the inputs passed to preceding calls to <a class="el" href="group__MAC.html#ga5560af371497babefe03c9da4e8a1c05">psa_mac_update()</a>.</p>
<p>When this function returns, the operation becomes inactive.</p>
<dl class="section warning"><dt>Warning</dt><dd>Applications should not call this function if they expect a specific value for the MAC. Call <a class="el" href="group__MAC.html#gac92b2930d6728e1be4d011c05d485822">psa_mac_verify_finish()</a> instead. Beware that comparing integrity or authenticity data such as MAC values with a function such as <code>memcmp</code> is risky because the time taken by the comparison may leak information about the MAC value which could allow an attacker to guess a valid MAC and thereby bypass security controls.</dd></dl>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">operation</td><td>Active MAC operation. </td></tr>
<tr><td class="paramdir">[out]</td><td class="paramname">mac</td><td>Buffer where the MAC value is to be written. </td></tr>
<tr><td class="paramdir"></td><td class="paramname">mac_size</td><td>Size of the <code>mac</code> buffer in bytes. </td></tr>
<tr><td class="paramdir">[out]</td><td class="paramname">mac_length</td><td>On success, the number of bytes that make up the MAC value. This is always <a class="el" href="crypto__sizes_8h.html#aa84c5fb384ac7cb1bfc52adde96588ee">PSA_MAC_FINAL_SIZE</a>(<code>key_type</code>, <code>key_bits</code>, <code>alg</code>) where <code>key_type</code> and <code>key_bits</code> are the type and bit-size respectively of the key and <code>alg</code> is the MAC algorithm that is calculated.</td></tr>
</table>
</dd>
</dl>
<dl class="retval"><dt>Return values</dt><dd>
<table class="retval">
<tr><td class="paramname"><a class="el" href="group__error.html#ga4cc859e2c66ca381c7418db3527a65e1">PSA_SUCCESS</a></td><td>Success. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga933d40fa2a591004f2e93aa91e11db84">PSA_ERROR_BAD_STATE</a></td><td>The operation state is not valid (not set up, or already completed). </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga695025f4ec11249aee7ea3d0f65e01c8">PSA_ERROR_BUFFER_TOO_SMALL</a></td><td>The size of the <code>mac</code> buffer is too small. You can determine a sufficient buffer size by calling <a class="el" href="crypto__sizes_8h.html#aa84c5fb384ac7cb1bfc52adde96588ee">PSA_MAC_FINAL_SIZE()</a>. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga91b2ad8a867517a2651f1b076c5216e5">PSA_ERROR_INSUFFICIENT_MEMORY</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga5cdb6948371d49e916106249020ea3f7">PSA_ERROR_COMMUNICATION_FAILURE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga08b10e70fa5ff0b05c631d9f8f6b2c6b">PSA_ERROR_HARDWARE_FAILURE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga2c5dda1485cb54f2385cb9c1279a7004">PSA_ERROR_TAMPERING_DETECTED</a></td><td></td></tr>
</table>
</dd>
</dl>
</div>
</div>
<a class="anchor" id="gad33f2b15119593571ca6b8e7c757ab0e"></a>
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<table class="memname">
<tr>
<td class="memname"><a class="el" href="group__error.html#ga05676e70ba5c6a7565aff3c36677c1f9">psa_status_t</a> psa_mac_sign_setup </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a> *&#160;</td>
<td class="paramname"><em>operation</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group__platform.html#gabf6d5fd4e2ea89ecd425c88f057e7f75">psa_key_handle_t</a>&#160;</td>
<td class="paramname"><em>handle</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group__crypto__types.html#gac2e4d47f1300d73c2f829a6d99252d69">psa_algorithm_t</a>&#160;</td>
<td class="paramname"><em>alg</em>&#160;</td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div><div class="memdoc">
<p>Set up a multipart MAC calculation operation.</p>
<p>This function sets up the calculation of the MAC (message authentication code) of a byte string. To verify the MAC of a message against an expected value, use <a class="el" href="group__MAC.html#gaa721a59ae6d085ec90c7dc918879a027">psa_mac_verify_setup()</a> instead.</p>
<p>The sequence of operations to calculate a MAC is as follows:</p><ol type="1">
<li>Allocate an operation object which will be passed to all the functions listed here.</li>
<li>Initialize the operation object with one of the methods described in the documentation for <a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a>, e.g. PSA_MAC_OPERATION_INIT.</li>
<li>Call <a class="el" href="group__MAC.html#gad33f2b15119593571ca6b8e7c757ab0e">psa_mac_sign_setup()</a> to specify the algorithm and key.</li>
<li>Call <a class="el" href="group__MAC.html#ga5560af371497babefe03c9da4e8a1c05">psa_mac_update()</a> zero, one or more times, passing a fragment of the message each time. The MAC that is calculated is the MAC of the concatenation of these messages in order.</li>
<li>At the end of the message, call <a class="el" href="group__MAC.html#gac22bc0125580c96724a09226cfbc97f2">psa_mac_sign_finish()</a> to finish calculating the MAC value and retrieve it.</li>
</ol>
<p>The application may call <a class="el" href="group__MAC.html#gacd8dd54855ba1bc0a03f104f252884fd">psa_mac_abort()</a> at any time after the operation has been initialized.</p>
<p>After a successful call to <a class="el" href="group__MAC.html#gad33f2b15119593571ca6b8e7c757ab0e">psa_mac_sign_setup()</a>, the application must eventually terminate the operation through one of the following methods:</p><ul>
<li>A failed call to <a class="el" href="group__MAC.html#ga5560af371497babefe03c9da4e8a1c05">psa_mac_update()</a>.</li>
<li>A call to <a class="el" href="group__MAC.html#gac22bc0125580c96724a09226cfbc97f2">psa_mac_sign_finish()</a> or <a class="el" href="group__MAC.html#gacd8dd54855ba1bc0a03f104f252884fd">psa_mac_abort()</a>.</li>
</ul>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">operation</td><td>The operation object to set up. It must have been initialized as per the documentation for <a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a> and not yet in use. </td></tr>
<tr><td class="paramdir"></td><td class="paramname">handle</td><td>Handle to the key to use for the operation. It must remain valid until the operation terminates. </td></tr>
<tr><td class="paramdir"></td><td class="paramname">alg</td><td>The MAC algorithm to compute (<code>PSA_ALG_XXX</code> value such that <a class="el" href="group__crypto__types.html#gaca7aee4c9dde316b3b1a150a26eab776">PSA_ALG_IS_MAC</a>(<code>alg</code>) is true).</td></tr>
</table>
</dd>
</dl>
<dl class="retval"><dt>Return values</dt><dd>
<table class="retval">
<tr><td class="paramname"><a class="el" href="group__error.html#ga4cc859e2c66ca381c7418db3527a65e1">PSA_SUCCESS</a></td><td>Success. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#gadf22718935657c2c3168c228204085f9">PSA_ERROR_INVALID_HANDLE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#gaba00e3e6ceb2b12965a81e5ac02ae040">PSA_ERROR_EMPTY_SLOT</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga4d1b8dd8526177a15a210b7afc1accb1">PSA_ERROR_NOT_PERMITTED</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga798df25a505ebf931f7bec1f80f1f85f">PSA_ERROR_INVALID_ARGUMENT</a></td><td><code>key</code> is not compatible with <code>alg</code>. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga1dcc6d130633ed5db8942257581b55dd">PSA_ERROR_NOT_SUPPORTED</a></td><td><code>alg</code> is not supported or is not a MAC algorithm. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga91b2ad8a867517a2651f1b076c5216e5">PSA_ERROR_INSUFFICIENT_MEMORY</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga5cdb6948371d49e916106249020ea3f7">PSA_ERROR_COMMUNICATION_FAILURE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga08b10e70fa5ff0b05c631d9f8f6b2c6b">PSA_ERROR_HARDWARE_FAILURE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga2c5dda1485cb54f2385cb9c1279a7004">PSA_ERROR_TAMPERING_DETECTED</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga933d40fa2a591004f2e93aa91e11db84">PSA_ERROR_BAD_STATE</a></td><td>The library has not been previously initialized by <a class="el" href="group__initialization.html#ga2de150803fc2f7dc6101d5af7e921dd9" title="Library initialization. ">psa_crypto_init()</a>. It is implementation-dependent whether a failure to initialize results in this error code. </td></tr>
</table>
</dd>
</dl>
</div>
</div>
<a class="anchor" id="ga5560af371497babefe03c9da4e8a1c05"></a>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname"><a class="el" href="group__error.html#ga05676e70ba5c6a7565aff3c36677c1f9">psa_status_t</a> psa_mac_update </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a> *&#160;</td>
<td class="paramname"><em>operation</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">const uint8_t *&#160;</td>
<td class="paramname"><em>input</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">size_t&#160;</td>
<td class="paramname"><em>input_length</em>&#160;</td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div><div class="memdoc">
<p>Add a message fragment to a multipart MAC operation.</p>
<p>The application must call <a class="el" href="group__MAC.html#gad33f2b15119593571ca6b8e7c757ab0e">psa_mac_sign_setup()</a> or <a class="el" href="group__MAC.html#gaa721a59ae6d085ec90c7dc918879a027">psa_mac_verify_setup()</a> before calling this function.</p>
<p>If this function returns an error status, the operation becomes inactive.</p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">operation</td><td>Active MAC operation. </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">input</td><td>Buffer containing the message fragment to add to the MAC calculation. </td></tr>
<tr><td class="paramdir"></td><td class="paramname">input_length</td><td>Size of the <code>input</code> buffer in bytes.</td></tr>
</table>
</dd>
</dl>
<dl class="retval"><dt>Return values</dt><dd>
<table class="retval">
<tr><td class="paramname"><a class="el" href="group__error.html#ga4cc859e2c66ca381c7418db3527a65e1">PSA_SUCCESS</a></td><td>Success. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga933d40fa2a591004f2e93aa91e11db84">PSA_ERROR_BAD_STATE</a></td><td>The operation state is not valid (not set up, or already completed). </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga91b2ad8a867517a2651f1b076c5216e5">PSA_ERROR_INSUFFICIENT_MEMORY</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga5cdb6948371d49e916106249020ea3f7">PSA_ERROR_COMMUNICATION_FAILURE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga08b10e70fa5ff0b05c631d9f8f6b2c6b">PSA_ERROR_HARDWARE_FAILURE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga2c5dda1485cb54f2385cb9c1279a7004">PSA_ERROR_TAMPERING_DETECTED</a></td><td></td></tr>
</table>
</dd>
</dl>
</div>
</div>
<a class="anchor" id="ga08e2e8c21bfe762a907266f3bdd1d07c"></a>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname"><a class="el" href="group__error.html#ga05676e70ba5c6a7565aff3c36677c1f9">psa_status_t</a> psa_mac_verify </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group__platform.html#gabf6d5fd4e2ea89ecd425c88f057e7f75">psa_key_handle_t</a>&#160;</td>
<td class="paramname"><em>handle</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group__crypto__types.html#gac2e4d47f1300d73c2f829a6d99252d69">psa_algorithm_t</a>&#160;</td>
<td class="paramname"><em>alg</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">const uint8_t *&#160;</td>
<td class="paramname"><em>input</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">size_t&#160;</td>
<td class="paramname"><em>input_length</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">const uint8_t *&#160;</td>
<td class="paramname"><em>mac</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">const size_t&#160;</td>
<td class="paramname"><em>mac_length</em>&#160;</td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div><div class="memdoc">
<p>Calculate the MAC of a message and compare it with a reference value.</p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir"></td><td class="paramname">handle</td><td>Handle to the key to use for the operation. </td></tr>
<tr><td class="paramdir"></td><td class="paramname">alg</td><td>The MAC algorithm to compute (<code>PSA_ALG_XXX</code> value such that <a class="el" href="group__crypto__types.html#gaca7aee4c9dde316b3b1a150a26eab776">PSA_ALG_IS_MAC</a>(<code>alg</code>) is true). </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">input</td><td>Buffer containing the input message. </td></tr>
<tr><td class="paramdir"></td><td class="paramname">input_length</td><td>Size of the <code>input</code> buffer in bytes. </td></tr>
<tr><td class="paramdir">[out]</td><td class="paramname">mac</td><td>Buffer containing the expected MAC value. </td></tr>
<tr><td class="paramdir"></td><td class="paramname">mac_length</td><td>Size of the <code>mac</code> buffer in bytes.</td></tr>
</table>
</dd>
</dl>
<dl class="retval"><dt>Return values</dt><dd>
<table class="retval">
<tr><td class="paramname"><a class="el" href="group__error.html#ga4cc859e2c66ca381c7418db3527a65e1">PSA_SUCCESS</a></td><td>The expected MAC is identical to the actual MAC of the input. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga35927f755d232c4766de600f2c49e9f2">PSA_ERROR_INVALID_SIGNATURE</a></td><td>The MAC of the message was calculated successfully, but it differs from the expected value. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#gadf22718935657c2c3168c228204085f9">PSA_ERROR_INVALID_HANDLE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#gaba00e3e6ceb2b12965a81e5ac02ae040">PSA_ERROR_EMPTY_SLOT</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga4d1b8dd8526177a15a210b7afc1accb1">PSA_ERROR_NOT_PERMITTED</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga798df25a505ebf931f7bec1f80f1f85f">PSA_ERROR_INVALID_ARGUMENT</a></td><td><code>key</code> is not compatible with <code>alg</code>. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga1dcc6d130633ed5db8942257581b55dd">PSA_ERROR_NOT_SUPPORTED</a></td><td><code>alg</code> is not supported or is not a MAC algorithm. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga91b2ad8a867517a2651f1b076c5216e5">PSA_ERROR_INSUFFICIENT_MEMORY</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga5cdb6948371d49e916106249020ea3f7">PSA_ERROR_COMMUNICATION_FAILURE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga08b10e70fa5ff0b05c631d9f8f6b2c6b">PSA_ERROR_HARDWARE_FAILURE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga2c5dda1485cb54f2385cb9c1279a7004">PSA_ERROR_TAMPERING_DETECTED</a></td><td></td></tr>
</table>
</dd>
</dl>
</div>
</div>
<a class="anchor" id="gac92b2930d6728e1be4d011c05d485822"></a>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname"><a class="el" href="group__error.html#ga05676e70ba5c6a7565aff3c36677c1f9">psa_status_t</a> psa_mac_verify_finish </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a> *&#160;</td>
<td class="paramname"><em>operation</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">const uint8_t *&#160;</td>
<td class="paramname"><em>mac</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">size_t&#160;</td>
<td class="paramname"><em>mac_length</em>&#160;</td>
</tr>
<tr>
<td></td>
<td>)</td>
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<p>Finish the calculation of the MAC of a message and compare it with an expected value.</p>
<p>The application must call <a class="el" href="group__MAC.html#gaa721a59ae6d085ec90c7dc918879a027">psa_mac_verify_setup()</a> before calling this function. This function calculates the MAC of the message formed by concatenating the inputs passed to preceding calls to <a class="el" href="group__MAC.html#ga5560af371497babefe03c9da4e8a1c05">psa_mac_update()</a>. It then compares the calculated MAC with the expected MAC passed as a parameter to this function.</p>
<p>When this function returns, the operation becomes inactive.</p>
<dl class="section note"><dt>Note</dt><dd>Implementations shall make the best effort to ensure that the comparison between the actual MAC and the expected MAC is performed in constant time.</dd></dl>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">operation</td><td>Active MAC operation. </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">mac</td><td>Buffer containing the expected MAC value. </td></tr>
<tr><td class="paramdir"></td><td class="paramname">mac_length</td><td>Size of the <code>mac</code> buffer in bytes.</td></tr>
</table>
</dd>
</dl>
<dl class="retval"><dt>Return values</dt><dd>
<table class="retval">
<tr><td class="paramname"><a class="el" href="group__error.html#ga4cc859e2c66ca381c7418db3527a65e1">PSA_SUCCESS</a></td><td>The expected MAC is identical to the actual MAC of the message. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga35927f755d232c4766de600f2c49e9f2">PSA_ERROR_INVALID_SIGNATURE</a></td><td>The MAC of the message was calculated successfully, but it differs from the expected MAC. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga933d40fa2a591004f2e93aa91e11db84">PSA_ERROR_BAD_STATE</a></td><td>The operation state is not valid (not set up, or already completed). </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga91b2ad8a867517a2651f1b076c5216e5">PSA_ERROR_INSUFFICIENT_MEMORY</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga5cdb6948371d49e916106249020ea3f7">PSA_ERROR_COMMUNICATION_FAILURE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga08b10e70fa5ff0b05c631d9f8f6b2c6b">PSA_ERROR_HARDWARE_FAILURE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga2c5dda1485cb54f2385cb9c1279a7004">PSA_ERROR_TAMPERING_DETECTED</a></td><td></td></tr>
</table>
</dd>
</dl>
</div>
</div>
<a class="anchor" id="gaa721a59ae6d085ec90c7dc918879a027"></a>
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<div class="memproto">
<table class="memname">
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<td class="memname"><a class="el" href="group__error.html#ga05676e70ba5c6a7565aff3c36677c1f9">psa_status_t</a> psa_mac_verify_setup </td>
<td>(</td>
<td class="paramtype"><a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a> *&#160;</td>
<td class="paramname"><em>operation</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group__platform.html#gabf6d5fd4e2ea89ecd425c88f057e7f75">psa_key_handle_t</a>&#160;</td>
<td class="paramname"><em>handle</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="group__crypto__types.html#gac2e4d47f1300d73c2f829a6d99252d69">psa_algorithm_t</a>&#160;</td>
<td class="paramname"><em>alg</em>&#160;</td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
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<p>Set up a multipart MAC verification operation.</p>
<p>This function sets up the verification of the MAC (message authentication code) of a byte string against an expected value.</p>
<p>The sequence of operations to verify a MAC is as follows:</p><ol type="1">
<li>Allocate an operation object which will be passed to all the functions listed here.</li>
<li>Initialize the operation object with one of the methods described in the documentation for <a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a>, e.g. PSA_MAC_OPERATION_INIT.</li>
<li>Call <a class="el" href="group__MAC.html#gaa721a59ae6d085ec90c7dc918879a027">psa_mac_verify_setup()</a> to specify the algorithm and key.</li>
<li>Call <a class="el" href="group__MAC.html#ga5560af371497babefe03c9da4e8a1c05">psa_mac_update()</a> zero, one or more times, passing a fragment of the message each time. The MAC that is calculated is the MAC of the concatenation of these messages in order.</li>
<li>At the end of the message, call <a class="el" href="group__MAC.html#gac92b2930d6728e1be4d011c05d485822">psa_mac_verify_finish()</a> to finish calculating the actual MAC of the message and verify it against the expected value.</li>
</ol>
<p>The application may call <a class="el" href="group__MAC.html#gacd8dd54855ba1bc0a03f104f252884fd">psa_mac_abort()</a> at any time after the operation has been initialized.</p>
<p>After a successful call to <a class="el" href="group__MAC.html#gaa721a59ae6d085ec90c7dc918879a027">psa_mac_verify_setup()</a>, the application must eventually terminate the operation through one of the following methods:</p><ul>
<li>A failed call to <a class="el" href="group__MAC.html#ga5560af371497babefe03c9da4e8a1c05">psa_mac_update()</a>.</li>
<li>A call to <a class="el" href="group__MAC.html#gac92b2930d6728e1be4d011c05d485822">psa_mac_verify_finish()</a> or <a class="el" href="group__MAC.html#gacd8dd54855ba1bc0a03f104f252884fd">psa_mac_abort()</a>.</li>
</ul>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in,out]</td><td class="paramname">operation</td><td>The operation object to set up. It must have been initialized as per the documentation for <a class="el" href="group__MAC.html#ga78f0838b0c4e3db28b26355624d4bd37">psa_mac_operation_t</a> and not yet in use. </td></tr>
<tr><td class="paramdir"></td><td class="paramname">handle</td><td>Handle to the key to use for the operation. It must remain valid until the operation terminates. </td></tr>
<tr><td class="paramdir"></td><td class="paramname">alg</td><td>The MAC algorithm to compute (<code>PSA_ALG_XXX</code> value such that <a class="el" href="group__crypto__types.html#gaca7aee4c9dde316b3b1a150a26eab776">PSA_ALG_IS_MAC</a>(<code>alg</code>) is true).</td></tr>
</table>
</dd>
</dl>
<dl class="retval"><dt>Return values</dt><dd>
<table class="retval">
<tr><td class="paramname"><a class="el" href="group__error.html#ga4cc859e2c66ca381c7418db3527a65e1">PSA_SUCCESS</a></td><td>Success. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#gadf22718935657c2c3168c228204085f9">PSA_ERROR_INVALID_HANDLE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#gaba00e3e6ceb2b12965a81e5ac02ae040">PSA_ERROR_EMPTY_SLOT</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga4d1b8dd8526177a15a210b7afc1accb1">PSA_ERROR_NOT_PERMITTED</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga798df25a505ebf931f7bec1f80f1f85f">PSA_ERROR_INVALID_ARGUMENT</a></td><td><code>key</code> is not compatible with <code>alg</code>. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga1dcc6d130633ed5db8942257581b55dd">PSA_ERROR_NOT_SUPPORTED</a></td><td><code>alg</code> is not supported or is not a MAC algorithm. </td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga91b2ad8a867517a2651f1b076c5216e5">PSA_ERROR_INSUFFICIENT_MEMORY</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga5cdb6948371d49e916106249020ea3f7">PSA_ERROR_COMMUNICATION_FAILURE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga08b10e70fa5ff0b05c631d9f8f6b2c6b">PSA_ERROR_HARDWARE_FAILURE</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga2c5dda1485cb54f2385cb9c1279a7004">PSA_ERROR_TAMPERING_DETECTED</a></td><td></td></tr>
<tr><td class="paramname"><a class="el" href="group__error.html#ga933d40fa2a591004f2e93aa91e11db84">PSA_ERROR_BAD_STATE</a></td><td>The library has not been previously initialized by <a class="el" href="group__initialization.html#ga2de150803fc2f7dc6101d5af7e921dd9" title="Library initialization. ">psa_crypto_init()</a>. It is implementation-dependent whether a failure to initialize results in this error code. </td></tr>
</table>
</dd>
</dl>
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