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<p>The Elliptic Curve Diffie-Hellman (ECDH) protocol APIs.
<a href="#details">More...</a></p>
<div class="textblock"><code>#include "<a class="el" href="ecp_8h_source.html">ecp.h</a>"</code><br />
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<p><a href="ecdh_8h_source.html">Go to the source code of this file.</a></p>
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Data Structures</h2></td></tr>
<tr class="memitem:"><td class="memItemLeft" align="right" valign="top">struct  </td><td class="memItemRight" valign="bottom"><a class="el" href="structmbedtls__ecdh__context.html">mbedtls_ecdh_context</a></td></tr>
<tr class="memdesc:"><td class="mdescLeft"> </td><td class="mdescRight">The ECDH context structure. <a href="structmbedtls__ecdh__context.html#details">More...</a><br /></td></tr>
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Enumerations</h2></td></tr>
<tr class="memitem:ae5df12f2068df09a102e05e02fb1e39c"><td class="memItemLeft" align="right" valign="top">enum  </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdh_8h.html#ae5df12f2068df09a102e05e02fb1e39c">mbedtls_ecdh_side</a> { <a class="el" href="ecdh_8h.html#ae5df12f2068df09a102e05e02fb1e39ca28e1b43484f53d02de24809228780703">MBEDTLS_ECDH_OURS</a>,
<a class="el" href="ecdh_8h.html#ae5df12f2068df09a102e05e02fb1e39caee83a43a270657fc7dc2f26c91d2addb">MBEDTLS_ECDH_THEIRS</a>
}</td></tr>
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Functions</h2></td></tr>
<tr class="memitem:a403a5d7363b6219a2017b837b665c354"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdh_8h.html#a403a5d7363b6219a2017b837b665c354">mbedtls_ecdh_gen_public</a> (<a class="el" href="structmbedtls__ecp__group.html">mbedtls_ecp_group</a> *grp, <a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> *d, <a class="el" href="structmbedtls__ecp__point.html">mbedtls_ecp_point</a> *Q, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)</td></tr>
<tr class="memdesc:a403a5d7363b6219a2017b837b665c354"><td class="mdescLeft"> </td><td class="mdescRight">This function generates an ECDH keypair on an elliptic curve. <a href="#a403a5d7363b6219a2017b837b665c354">More...</a><br /></td></tr>
<tr class="separator:a403a5d7363b6219a2017b837b665c354"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:aca0670e79f3002a218d6da8c8dee61e1"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdh_8h.html#aca0670e79f3002a218d6da8c8dee61e1">mbedtls_ecdh_compute_shared</a> (<a class="el" href="structmbedtls__ecp__group.html">mbedtls_ecp_group</a> *grp, <a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> *z, const <a class="el" href="structmbedtls__ecp__point.html">mbedtls_ecp_point</a> *Q, const <a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> *d, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)</td></tr>
<tr class="memdesc:aca0670e79f3002a218d6da8c8dee61e1"><td class="mdescLeft"> </td><td class="mdescRight">This function computes the shared secret. <a href="#aca0670e79f3002a218d6da8c8dee61e1">More...</a><br /></td></tr>
<tr class="separator:aca0670e79f3002a218d6da8c8dee61e1"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a97e787a12f7aae180ab9828303199dca"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdh_8h.html#a97e787a12f7aae180ab9828303199dca">mbedtls_ecdh_init</a> (<a class="el" href="structmbedtls__ecdh__context.html">mbedtls_ecdh_context</a> *ctx)</td></tr>
<tr class="memdesc:a97e787a12f7aae180ab9828303199dca"><td class="mdescLeft"> </td><td class="mdescRight">This function initializes an ECDH context. <a href="#a97e787a12f7aae180ab9828303199dca">More...</a><br /></td></tr>
<tr class="separator:a97e787a12f7aae180ab9828303199dca"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a89cc40dc92fbbaf0275ea9a6184a5e71"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdh_8h.html#a89cc40dc92fbbaf0275ea9a6184a5e71">mbedtls_ecdh_free</a> (<a class="el" href="structmbedtls__ecdh__context.html">mbedtls_ecdh_context</a> *ctx)</td></tr>
<tr class="memdesc:a89cc40dc92fbbaf0275ea9a6184a5e71"><td class="mdescLeft"> </td><td class="mdescRight">This function frees a context. <a href="#a89cc40dc92fbbaf0275ea9a6184a5e71">More...</a><br /></td></tr>
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<tr class="memitem:a784e56d5eea12e38374e9ce028692940"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdh_8h.html#a784e56d5eea12e38374e9ce028692940">mbedtls_ecdh_make_params</a> (<a class="el" href="structmbedtls__ecdh__context.html">mbedtls_ecdh_context</a> *ctx, size_t *olen, unsigned char *buf, size_t blen, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)</td></tr>
<tr class="memdesc:a784e56d5eea12e38374e9ce028692940"><td class="mdescLeft"> </td><td class="mdescRight">This function generates a public key and a TLS ServerKeyExchange payload. <a href="#a784e56d5eea12e38374e9ce028692940">More...</a><br /></td></tr>
<tr class="separator:a784e56d5eea12e38374e9ce028692940"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:af07326ad0017bf6fcfb9f93e43641254"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdh_8h.html#af07326ad0017bf6fcfb9f93e43641254">mbedtls_ecdh_read_params</a> (<a class="el" href="structmbedtls__ecdh__context.html">mbedtls_ecdh_context</a> *ctx, const unsigned char **buf, const unsigned char *end)</td></tr>
<tr class="memdesc:af07326ad0017bf6fcfb9f93e43641254"><td class="mdescLeft"> </td><td class="mdescRight">This function parses and processes a TLS ServerKeyExhange payload. <a href="#af07326ad0017bf6fcfb9f93e43641254">More...</a><br /></td></tr>
<tr class="separator:af07326ad0017bf6fcfb9f93e43641254"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a3c03b82213c39abd90a5bd4b1646441d"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdh_8h.html#a3c03b82213c39abd90a5bd4b1646441d">mbedtls_ecdh_get_params</a> (<a class="el" href="structmbedtls__ecdh__context.html">mbedtls_ecdh_context</a> *ctx, const <a class="el" href="structmbedtls__ecp__keypair.html">mbedtls_ecp_keypair</a> *key, <a class="el" href="ecdh_8h.html#ae5df12f2068df09a102e05e02fb1e39c">mbedtls_ecdh_side</a> side)</td></tr>
<tr class="memdesc:a3c03b82213c39abd90a5bd4b1646441d"><td class="mdescLeft"> </td><td class="mdescRight">This function sets up an ECDH context from an EC key. <a href="#a3c03b82213c39abd90a5bd4b1646441d">More...</a><br /></td></tr>
<tr class="separator:a3c03b82213c39abd90a5bd4b1646441d"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a417fd45ce78adb1b52027f995fa5ee57"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdh_8h.html#a417fd45ce78adb1b52027f995fa5ee57">mbedtls_ecdh_make_public</a> (<a class="el" href="structmbedtls__ecdh__context.html">mbedtls_ecdh_context</a> *ctx, size_t *olen, unsigned char *buf, size_t blen, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)</td></tr>
<tr class="memdesc:a417fd45ce78adb1b52027f995fa5ee57"><td class="mdescLeft"> </td><td class="mdescRight">This function generates a public key and a TLS ClientKeyExchange payload. <a href="#a417fd45ce78adb1b52027f995fa5ee57">More...</a><br /></td></tr>
<tr class="separator:a417fd45ce78adb1b52027f995fa5ee57"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a9f417d90797b109d3036feb288e33207"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdh_8h.html#a9f417d90797b109d3036feb288e33207">mbedtls_ecdh_read_public</a> (<a class="el" href="structmbedtls__ecdh__context.html">mbedtls_ecdh_context</a> *ctx, const unsigned char *buf, size_t blen)</td></tr>
<tr class="memdesc:a9f417d90797b109d3036feb288e33207"><td class="mdescLeft"> </td><td class="mdescRight">This function parses and processes a TLS ClientKeyExchange payload. <a href="#a9f417d90797b109d3036feb288e33207">More...</a><br /></td></tr>
<tr class="separator:a9f417d90797b109d3036feb288e33207"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a423fee27a0c8603bba336cbfe6dadcaa"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdh_8h.html#a423fee27a0c8603bba336cbfe6dadcaa">mbedtls_ecdh_calc_secret</a> (<a class="el" href="structmbedtls__ecdh__context.html">mbedtls_ecdh_context</a> *ctx, size_t *olen, unsigned char *buf, size_t blen, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)</td></tr>
<tr class="memdesc:a423fee27a0c8603bba336cbfe6dadcaa"><td class="mdescLeft"> </td><td class="mdescRight">This function derives and exports the shared secret. <a href="#a423fee27a0c8603bba336cbfe6dadcaa">More...</a><br /></td></tr>
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<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<div class="textblock"><p>The Elliptic Curve Diffie-Hellman (ECDH) protocol APIs. </p>
<p>ECDH is an anonymous key agreement protocol allowing two parties to establish a shared secret over an insecure channel. Each party must have an elliptic-curve public–private key pair.</p>
<p>For more information, see <em>NIST SP 800-56A Rev. 2: Recommendation for Pair-Wise Key Establishment Schemes Using Discrete Logarithm Cryptography</em>. </p>
<p class="definition">Definition in file <a class="el" href="ecdh_8h_source.html">ecdh.h</a>.</p>
</div><h2 class="groupheader">Enumeration Type Documentation</h2>
<a id="ae5df12f2068df09a102e05e02fb1e39c"></a>
<h2 class="memtitle"><span class="permalink"><a href="#ae5df12f2068df09a102e05e02fb1e39c">◆ </a></span>mbedtls_ecdh_side</h2>
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<div class="memproto">
<table class="memname">
<tr>
<td class="memname">enum <a class="el" href="ecdh_8h.html#ae5df12f2068df09a102e05e02fb1e39c">mbedtls_ecdh_side</a></td>
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<p>Defines the source of the imported EC key: </p><ul>
<li>
Our key. </li>
<li>
The key of the peer.</li>
</ul>
<table class="fieldtable">
<tr><th colspan="2">Enumerator</th></tr><tr><td class="fieldname"><a id="ae5df12f2068df09a102e05e02fb1e39ca28e1b43484f53d02de24809228780703"></a>MBEDTLS_ECDH_OURS </td><td class="fielddoc"></td></tr>
<tr><td class="fieldname"><a id="ae5df12f2068df09a102e05e02fb1e39caee83a43a270657fc7dc2f26c91d2addb"></a>MBEDTLS_ECDH_THEIRS </td><td class="fielddoc"></td></tr>
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<p class="definition">Definition at line <a class="el" href="ecdh_8h_source.html#l00047">47</a> of file <a class="el" href="ecdh_8h_source.html">ecdh.h</a>.</p>
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<h2 class="groupheader">Function Documentation</h2>
<a id="a423fee27a0c8603bba336cbfe6dadcaa"></a>
<h2 class="memtitle"><span class="permalink"><a href="#a423fee27a0c8603bba336cbfe6dadcaa">◆ </a></span>mbedtls_ecdh_calc_secret()</h2>
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<td class="memname">int mbedtls_ecdh_calc_secret </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structmbedtls__ecdh__context.html">mbedtls_ecdh_context</a> * </td>
<td class="paramname"><em>ctx</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">size_t * </td>
<td class="paramname"><em>olen</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">unsigned char * </td>
<td class="paramname"><em>buf</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">size_t </td>
<td class="paramname"><em>blen</em>, </td>
</tr>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">int(*)(void *, unsigned char *, size_t) </td>
<td class="paramname"><em>f_rng</em>, </td>
</tr>
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<td class="paramkey"></td>
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<td class="paramtype">void * </td>
<td class="paramname"><em>p_rng</em> </td>
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<p>This function derives and exports the shared secret. </p>
<p>This is the last function used by both TLS client and servers.</p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">ctx</td><td>The ECDH context. </td></tr>
<tr><td class="paramname">olen</td><td>The number of Bytes written. </td></tr>
<tr><td class="paramname">buf</td><td>The destination buffer. </td></tr>
<tr><td class="paramname">blen</td><td>The length of the destination buffer. </td></tr>
<tr><td class="paramname">f_rng</td><td>The RNG function. </td></tr>
<tr><td class="paramname">p_rng</td><td>The RNG parameter.</td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd><code>0</code> on success, or an <code>MBEDTLS_ERR_ECP_XXX</code> error code on failure.</dd></dl>
<dl class="section see"><dt>See also</dt><dd><a class="el" href="ecp_8h.html" title="Elliptic curves over GF(p) ">ecp.h</a></dd></dl>
<dl class="section note"><dt>Note</dt><dd>If <code>f_rng</code> is not NULL, it is used to implement countermeasures against potential elaborate timing attacks. For more information, see <a class="el" href="ecp_8h.html#a4d005045c302e100c78bdc587e8f0e6a" title="Multiplication by an integer: R = m * P (Not thread-safe to use same group in multiple threads) ...">mbedtls_ecp_mul()</a>. </dd></dl>
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<h2 class="memtitle"><span class="permalink"><a href="#aca0670e79f3002a218d6da8c8dee61e1">◆ </a></span>mbedtls_ecdh_compute_shared()</h2>
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<td class="memname">int mbedtls_ecdh_compute_shared </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structmbedtls__ecp__group.html">mbedtls_ecp_group</a> * </td>
<td class="paramname"><em>grp</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> * </td>
<td class="paramname"><em>z</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">const <a class="el" href="structmbedtls__ecp__point.html">mbedtls_ecp_point</a> * </td>
<td class="paramname"><em>Q</em>, </td>
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<td class="paramkey"></td>
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<td class="paramtype">const <a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> * </td>
<td class="paramname"><em>d</em>, </td>
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<td class="paramtype">int(*)(void *, unsigned char *, size_t) </td>
<td class="paramname"><em>f_rng</em>, </td>
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<td class="paramtype">void * </td>
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<p>This function computes the shared secret. </p>
<p>This function performs the second of two core computations implemented during the ECDH key exchange. The first core computation is performed by <a class="el" href="ecdh_8h.html#a403a5d7363b6219a2017b837b665c354" title="This function generates an ECDH keypair on an elliptic curve. ">mbedtls_ecdh_gen_public()</a>.</p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">grp</td><td>The ECP group. </td></tr>
<tr><td class="paramname">z</td><td>The destination MPI (shared secret). </td></tr>
<tr><td class="paramname">Q</td><td>The public key from another party. </td></tr>
<tr><td class="paramname">d</td><td>Our secret exponent (private key). </td></tr>
<tr><td class="paramname">f_rng</td><td>The RNG function. </td></tr>
<tr><td class="paramname">p_rng</td><td>The RNG parameter.</td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd><code>0</code> on success, or an <code>MBEDTLS_ERR_ECP_XXX</code> or <code>MBEDTLS_MPI_XXX</code> error code on failure.</dd></dl>
<dl class="section see"><dt>See also</dt><dd><a class="el" href="ecp_8h.html" title="Elliptic curves over GF(p) ">ecp.h</a></dd></dl>
<dl class="section note"><dt>Note</dt><dd>If <code>f_rng</code> is not NULL, it is used to implement countermeasures against potential elaborate timing attacks. For more information, see <a class="el" href="ecp_8h.html#a4d005045c302e100c78bdc587e8f0e6a" title="Multiplication by an integer: R = m * P (Not thread-safe to use same group in multiple threads) ...">mbedtls_ecp_mul()</a>. </dd></dl>
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<h2 class="memtitle"><span class="permalink"><a href="#a89cc40dc92fbbaf0275ea9a6184a5e71">◆ </a></span>mbedtls_ecdh_free()</h2>
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<td class="memname">void mbedtls_ecdh_free </td>
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<td class="paramtype"><a class="el" href="structmbedtls__ecdh__context.html">mbedtls_ecdh_context</a> * </td>
<td class="paramname"><em>ctx</em></td><td>)</td>
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<p>This function frees a context. </p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">ctx</td><td>The context to free. </td></tr>
</table>
</dd>
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<a id="a403a5d7363b6219a2017b837b665c354"></a>
<h2 class="memtitle"><span class="permalink"><a href="#a403a5d7363b6219a2017b837b665c354">◆ </a></span>mbedtls_ecdh_gen_public()</h2>
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<td class="memname">int mbedtls_ecdh_gen_public </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structmbedtls__ecp__group.html">mbedtls_ecp_group</a> * </td>
<td class="paramname"><em>grp</em>, </td>
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<td class="paramtype"><a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> * </td>
<td class="paramname"><em>d</em>, </td>
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<td class="paramkey"></td>
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<td class="paramtype"><a class="el" href="structmbedtls__ecp__point.html">mbedtls_ecp_point</a> * </td>
<td class="paramname"><em>Q</em>, </td>
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<td class="paramtype">int(*)(void *, unsigned char *, size_t) </td>
<td class="paramname"><em>f_rng</em>, </td>
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<tr>
<td class="paramkey"></td>
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<td class="paramtype">void * </td>
<td class="paramname"><em>p_rng</em> </td>
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<p>This function generates an ECDH keypair on an elliptic curve. </p>
<p>This function performs the first of two core computations implemented during the ECDH key exchange. The second core computation is performed by <a class="el" href="ecdh_8h.html#aca0670e79f3002a218d6da8c8dee61e1" title="This function computes the shared secret. ">mbedtls_ecdh_compute_shared()</a>.</p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">grp</td><td>The ECP group. </td></tr>
<tr><td class="paramname">d</td><td>The destination MPI (private key). </td></tr>
<tr><td class="paramname">Q</td><td>The destination point (public key). </td></tr>
<tr><td class="paramname">f_rng</td><td>The RNG function. </td></tr>
<tr><td class="paramname">p_rng</td><td>The RNG parameter.</td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd><code>0</code> on success, or an <code>MBEDTLS_ERR_ECP_XXX</code> or <code>MBEDTLS_MPI_XXX</code> error code on failure.</dd></dl>
<dl class="section see"><dt>See also</dt><dd><a class="el" href="ecp_8h.html" title="Elliptic curves over GF(p) ">ecp.h</a> </dd></dl>
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<h2 class="memtitle"><span class="permalink"><a href="#a3c03b82213c39abd90a5bd4b1646441d">◆ </a></span>mbedtls_ecdh_get_params()</h2>
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<td class="memname">int mbedtls_ecdh_get_params </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structmbedtls__ecdh__context.html">mbedtls_ecdh_context</a> * </td>
<td class="paramname"><em>ctx</em>, </td>
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<td class="paramkey"></td>
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<td class="paramtype">const <a class="el" href="structmbedtls__ecp__keypair.html">mbedtls_ecp_keypair</a> * </td>
<td class="paramname"><em>key</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="ecdh_8h.html#ae5df12f2068df09a102e05e02fb1e39c">mbedtls_ecdh_side</a> </td>
<td class="paramname"><em>side</em> </td>
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<p>This function sets up an ECDH context from an EC key. </p>
<p>It is used by clients and servers in place of the ServerKeyEchange for static ECDH, and imports ECDH parameters from the EC key information of a certificate.</p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">ctx</td><td>The ECDH context to set up. </td></tr>
<tr><td class="paramname">key</td><td>The EC key to use. </td></tr>
<tr><td class="paramname">side</td><td>Defines the source of the key: <ul>
<li>
1: Our key. </li>
<li>
0: The key of the peer.</li>
</ul>
</td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd><code>0</code> on success, or an <code>MBEDTLS_ERR_ECP_XXX</code> error code on failure.</dd></dl>
<dl class="section see"><dt>See also</dt><dd><a class="el" href="ecp_8h.html" title="Elliptic curves over GF(p) ">ecp.h</a> </dd></dl>
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<h2 class="memtitle"><span class="permalink"><a href="#a97e787a12f7aae180ab9828303199dca">◆ </a></span>mbedtls_ecdh_init()</h2>
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<td class="memname">void mbedtls_ecdh_init </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structmbedtls__ecdh__context.html">mbedtls_ecdh_context</a> * </td>
<td class="paramname"><em>ctx</em></td><td>)</td>
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<p>This function initializes an ECDH context. </p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">ctx</td><td>The ECDH context to initialize. </td></tr>
</table>
</dd>
</dl>
</div>
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<h2 class="memtitle"><span class="permalink"><a href="#a784e56d5eea12e38374e9ce028692940">◆ </a></span>mbedtls_ecdh_make_params()</h2>
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<td class="memname">int mbedtls_ecdh_make_params </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structmbedtls__ecdh__context.html">mbedtls_ecdh_context</a> * </td>
<td class="paramname"><em>ctx</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">size_t * </td>
<td class="paramname"><em>olen</em>, </td>
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<td class="paramkey"></td>
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<td class="paramtype">unsigned char * </td>
<td class="paramname"><em>buf</em>, </td>
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<td class="paramkey"></td>
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<td class="paramtype">size_t </td>
<td class="paramname"><em>blen</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">int(*)(void *, unsigned char *, size_t) </td>
<td class="paramname"><em>f_rng</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">void * </td>
<td class="paramname"><em>p_rng</em> </td>
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<p>This function generates a public key and a TLS ServerKeyExchange payload. </p>
<p>This is the first function used by a TLS server for ECDHE ciphersuites.</p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">ctx</td><td>The ECDH context. </td></tr>
<tr><td class="paramname">olen</td><td>The number of characters written. </td></tr>
<tr><td class="paramname">buf</td><td>The destination buffer. </td></tr>
<tr><td class="paramname">blen</td><td>The length of the destination buffer. </td></tr>
<tr><td class="paramname">f_rng</td><td>The RNG function. </td></tr>
<tr><td class="paramname">p_rng</td><td>The RNG parameter.</td></tr>
</table>
</dd>
</dl>
<dl class="section note"><dt>Note</dt><dd>This function assumes that the ECP group (grp) of the <code>ctx</code> context has already been properly set, for example, using <a class="el" href="ecp_8h.html#a64439a12deff8bd1ef92eeab7ebbcf93" title="Set a group using well-known domain parameters. ">mbedtls_ecp_group_load()</a>.</dd></dl>
<dl class="section return"><dt>Returns</dt><dd><code>0</code> on success, or an <code>MBEDTLS_ERR_ECP_XXX</code> error code on failure.</dd></dl>
<dl class="section see"><dt>See also</dt><dd><a class="el" href="ecp_8h.html" title="Elliptic curves over GF(p) ">ecp.h</a> </dd></dl>
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<h2 class="memtitle"><span class="permalink"><a href="#a417fd45ce78adb1b52027f995fa5ee57">◆ </a></span>mbedtls_ecdh_make_public()</h2>
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<td class="memname">int mbedtls_ecdh_make_public </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structmbedtls__ecdh__context.html">mbedtls_ecdh_context</a> * </td>
<td class="paramname"><em>ctx</em>, </td>
</tr>
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<td class="paramkey"></td>
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<td class="paramtype">size_t * </td>
<td class="paramname"><em>olen</em>, </td>
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<td class="paramkey"></td>
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<td class="paramtype">unsigned char * </td>
<td class="paramname"><em>buf</em>, </td>
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<td class="paramkey"></td>
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<td class="paramtype">size_t </td>
<td class="paramname"><em>blen</em>, </td>
</tr>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">int(*)(void *, unsigned char *, size_t) </td>
<td class="paramname"><em>f_rng</em>, </td>
</tr>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">void * </td>
<td class="paramname"><em>p_rng</em> </td>
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<p>This function generates a public key and a TLS ClientKeyExchange payload. </p>
<p>This is the second function used by a TLS client for ECDH(E) ciphersuites.</p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">ctx</td><td>The ECDH context. </td></tr>
<tr><td class="paramname">olen</td><td>The number of Bytes written. </td></tr>
<tr><td class="paramname">buf</td><td>The destination buffer. </td></tr>
<tr><td class="paramname">blen</td><td>The size of the destination buffer. </td></tr>
<tr><td class="paramname">f_rng</td><td>The RNG function. </td></tr>
<tr><td class="paramname">p_rng</td><td>The RNG parameter.</td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd><code>0</code> on success, or an <code>MBEDTLS_ERR_ECP_XXX</code> error code on failure.</dd></dl>
<dl class="section see"><dt>See also</dt><dd><a class="el" href="ecp_8h.html" title="Elliptic curves over GF(p) ">ecp.h</a> </dd></dl>
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<h2 class="memtitle"><span class="permalink"><a href="#af07326ad0017bf6fcfb9f93e43641254">◆ </a></span>mbedtls_ecdh_read_params()</h2>
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<td class="memname">int mbedtls_ecdh_read_params </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structmbedtls__ecdh__context.html">mbedtls_ecdh_context</a> * </td>
<td class="paramname"><em>ctx</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">const unsigned char ** </td>
<td class="paramname"><em>buf</em>, </td>
</tr>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">const unsigned char * </td>
<td class="paramname"><em>end</em> </td>
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<td></td>
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<p>This function parses and processes a TLS ServerKeyExhange payload. </p>
<p>This is the first function used by a TLS client for ECDHE ciphersuites.</p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">ctx</td><td>The ECDH context. </td></tr>
<tr><td class="paramname">buf</td><td>The pointer to the start of the input buffer. </td></tr>
<tr><td class="paramname">end</td><td>The address for one Byte past the end of the buffer.</td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd><code>0</code> on success, or an <code>MBEDTLS_ERR_ECP_XXX</code> error code on failure.</dd></dl>
<dl class="section see"><dt>See also</dt><dd><a class="el" href="ecp_8h.html" title="Elliptic curves over GF(p) ">ecp.h</a> </dd></dl>
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<h2 class="memtitle"><span class="permalink"><a href="#a9f417d90797b109d3036feb288e33207">◆ </a></span>mbedtls_ecdh_read_public()</h2>
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<td class="memname">int mbedtls_ecdh_read_public </td>
<td>(</td>
<td class="paramtype"><a class="el" href="structmbedtls__ecdh__context.html">mbedtls_ecdh_context</a> * </td>
<td class="paramname"><em>ctx</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">const unsigned char * </td>
<td class="paramname"><em>buf</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">size_t </td>
<td class="paramname"><em>blen</em> </td>
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<td></td>
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<p>This function parses and processes a TLS ClientKeyExchange payload. </p>
<p>This is the second function used by a TLS server for ECDH(E) ciphersuites.</p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">ctx</td><td>The ECDH context. </td></tr>
<tr><td class="paramname">buf</td><td>The start of the input buffer. </td></tr>
<tr><td class="paramname">blen</td><td>The length of the input buffer.</td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd><code>0</code> on success, or an <code>MBEDTLS_ERR_ECP_XXX</code> error code on failure.</dd></dl>
<dl class="section see"><dt>See also</dt><dd><a class="el" href="ecp_8h.html" title="Elliptic curves over GF(p) ">ecp.h</a> </dd></dl>
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