<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/> <meta http-equiv="X-UA-Compatible" content="IE=9"/> <meta name="generator" content="Doxygen 1.8.13"/> <meta name="viewport" content="width=device-width, initial-scale=1"/> <title>mbed TLS v2.7.8: ecdsa.h File Reference</title> <link href="tabs.css" rel="stylesheet" type="text/css"/> <script type="text/javascript" src="jquery.js"></script> <script type="text/javascript" src="dynsections.js"></script> <link href="doxygen.css" rel="stylesheet" type="text/css" /> </head> <body> <div id="top"><!-- do not remove this div, it is closed by doxygen! --> <div id="titlearea"> <table cellspacing="0" cellpadding="0"> <tbody> <tr style="height: 56px;"> <td id="projectalign" style="padding-left: 0.5em;"> <div id="projectname">mbed TLS v2.7.8 </div> </td> </tr> </tbody> </table> </div> <!-- end header part --> <!-- Generated by Doxygen 1.8.13 --> <script type="text/javascript" src="menudata.js"></script> <script type="text/javascript" src="menu.js"></script> <script type="text/javascript"> $(function() { initMenu('',false,false,'search.php','Search'); }); </script> <div id="main-nav"></div> <div id="nav-path" class="navpath"> <ul> <li class="navelem"><a class="el" href="dir_d44c64559bbebec7f509842c48db8b23.html">include</a></li><li class="navelem"><a class="el" href="dir_b4d146e9a6d8dd56ed4afb2480a97fd3.html">mbedtls</a></li> </ul> </div> </div><!-- top --> <div class="header"> <div class="summary"> <a href="#define-members">Macros</a> | <a href="#typedef-members">Typedefs</a> | <a href="#func-members">Functions</a> </div> <div class="headertitle"> <div class="title">ecdsa.h File Reference</div> </div> </div><!--header--> <div class="contents"> <p>The Elliptic Curve Digital Signature Algorithm (ECDSA). <a href="#details">More...</a></p> <div class="textblock"><code>#include "<a class="el" href="ecp_8h_source.html">ecp.h</a>"</code><br /> <code>#include "<a class="el" href="md_8h_source.html">md.h</a>"</code><br /> </div><div class="textblock"><div class="dynheader"> Include dependency graph for ecdsa.h:</div> <div class="dyncontent"> <div class="center"><img src="ecdsa_8h__incl.png" border="0" usemap="#ecdsa_8h" alt=""/></div> <map name="ecdsa_8h" id="ecdsa_8h"> <area shape="rect" id="node2" href="ecp_8h.html" title="Elliptic curves over GF(p) " alt="" coords="221,80,293,107"/> <area shape="rect" id="node10" href="md_8h.html" title="The generic message-digest wrapper. 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" alt="" coords="499,229,622,256"/> </map> </div> </div> <p><a href="ecdsa_8h_source.html">Go to the source code of this file.</a></p> <table class="memberdecls"> <tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="define-members"></a> Macros</h2></td></tr> <tr class="memitem:aeb07d11aef4d847c5cc5cfba49547136"><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdsa_8h.html#aeb07d11aef4d847c5cc5cfba49547136">MBEDTLS_ECDSA_MAX_LEN</a>   ( 3 + 2 * ( 3 + <a class="el" href="ecp_8h.html#aba9fdfc8a8dd423182616e5708abf607">MBEDTLS_ECP_MAX_BYTES</a> ) )</td></tr> <tr class="separator:aeb07d11aef4d847c5cc5cfba49547136"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:aa9f53b232ef244efb301233d111930dc"><td class="memItemLeft" align="right" valign="top">#define </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdsa_8h.html#aa9f53b232ef244efb301233d111930dc">MBEDTLS_DEPRECATED</a></td></tr> <tr class="separator:aa9f53b232ef244efb301233d111930dc"><td class="memSeparator" colspan="2"> </td></tr> </table><table class="memberdecls"> <tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="typedef-members"></a> Typedefs</h2></td></tr> <tr class="memitem:a86ad4c743272c83310c20585ec7a182f"><td class="memItemLeft" align="right" valign="top">typedef <a class="el" href="structmbedtls__ecp__keypair.html">mbedtls_ecp_keypair</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdsa_8h.html#a86ad4c743272c83310c20585ec7a182f">mbedtls_ecdsa_context</a></td></tr> <tr class="memdesc:a86ad4c743272c83310c20585ec7a182f"><td class="mdescLeft"> </td><td class="mdescRight">The ECDSA context structure. <a href="#a86ad4c743272c83310c20585ec7a182f">More...</a><br /></td></tr> <tr class="separator:a86ad4c743272c83310c20585ec7a182f"><td class="memSeparator" colspan="2"> </td></tr> </table><table class="memberdecls"> <tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="func-members"></a> Functions</h2></td></tr> <tr class="memitem:af10f6fda2169862871d0ac07555c8641"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdsa_8h.html#af10f6fda2169862871d0ac07555c8641">mbedtls_ecdsa_sign</a> (<a class="el" href="structmbedtls__ecp__group.html">mbedtls_ecp_group</a> *grp, <a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> *r, <a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> *s, const <a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> *d, const unsigned char *buf, size_t blen, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)</td></tr> <tr class="memdesc:af10f6fda2169862871d0ac07555c8641"><td class="mdescLeft"> </td><td class="mdescRight">This function computes the ECDSA signature of a previously-hashed message. <a href="#af10f6fda2169862871d0ac07555c8641">More...</a><br /></td></tr> <tr class="separator:af10f6fda2169862871d0ac07555c8641"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:a381af8cc9ab0146a4cf1ba5226c81a8f"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdsa_8h.html#a381af8cc9ab0146a4cf1ba5226c81a8f">mbedtls_ecdsa_sign_det</a> (<a class="el" href="structmbedtls__ecp__group.html">mbedtls_ecp_group</a> *grp, <a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> *r, <a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> *s, const <a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> *d, const unsigned char *buf, size_t blen, <a class="el" href="md_8h.html#a219313cb40503ec3e34a857ab98b2296">mbedtls_md_type_t</a> md_alg)</td></tr> <tr class="memdesc:a381af8cc9ab0146a4cf1ba5226c81a8f"><td class="mdescLeft"> </td><td class="mdescRight">This function computes the ECDSA signature of a previously-hashed message, deterministic version. For more information, see <em>RFC-6979: Deterministic Usage of the Digital Signature Algorithm (DSA) and Elliptic Curve Digital Signature Algorithm (ECDSA)</em>. <a href="#a381af8cc9ab0146a4cf1ba5226c81a8f">More...</a><br /></td></tr> <tr class="separator:a381af8cc9ab0146a4cf1ba5226c81a8f"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:a2292032f359fda59a7fd14911cc56f38"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdsa_8h.html#a2292032f359fda59a7fd14911cc56f38">mbedtls_ecdsa_verify</a> (<a class="el" href="structmbedtls__ecp__group.html">mbedtls_ecp_group</a> *grp, const unsigned char *buf, size_t blen, 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> *r, const <a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> *s)</td></tr> <tr class="memdesc:a2292032f359fda59a7fd14911cc56f38"><td class="mdescLeft"> </td><td class="mdescRight">This function verifies the ECDSA signature of a previously-hashed message. <a href="#a2292032f359fda59a7fd14911cc56f38">More...</a><br /></td></tr> <tr class="separator:a2292032f359fda59a7fd14911cc56f38"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:a76da70289de1f746ad9cce1eadf7b135"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdsa_8h.html#a76da70289de1f746ad9cce1eadf7b135">mbedtls_ecdsa_write_signature</a> (<a class="el" href="ecdsa_8h.html#a86ad4c743272c83310c20585ec7a182f">mbedtls_ecdsa_context</a> *ctx, <a class="el" href="md_8h.html#a219313cb40503ec3e34a857ab98b2296">mbedtls_md_type_t</a> md_alg, const unsigned char *hash, size_t hlen, unsigned char *sig, size_t *slen, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)</td></tr> <tr class="memdesc:a76da70289de1f746ad9cce1eadf7b135"><td class="mdescLeft"> </td><td class="mdescRight">This function computes the ECDSA signature and writes it to a buffer, serialized as defined in <em>RFC-4492: Elliptic Curve Cryptography (ECC) Cipher Suites for Transport Layer Security (TLS)</em>. <a href="#a76da70289de1f746ad9cce1eadf7b135">More...</a><br /></td></tr> <tr class="separator:a76da70289de1f746ad9cce1eadf7b135"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:a3827a7cf6502530e831e0bb1fcfdd5d8"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdsa_8h.html#a3827a7cf6502530e831e0bb1fcfdd5d8">mbedtls_ecdsa_write_signature_det</a> (<a class="el" href="ecdsa_8h.html#a86ad4c743272c83310c20585ec7a182f">mbedtls_ecdsa_context</a> *ctx, const unsigned char *hash, size_t hlen, unsigned char *sig, size_t *slen, <a class="el" href="md_8h.html#a219313cb40503ec3e34a857ab98b2296">mbedtls_md_type_t</a> md_alg) <a class="el" href="ssl_8h.html#aa9f53b232ef244efb301233d111930dc">MBEDTLS_DEPRECATED</a></td></tr> <tr class="memdesc:a3827a7cf6502530e831e0bb1fcfdd5d8"><td class="mdescLeft"> </td><td class="mdescRight">This function computes an ECDSA signature and writes it to a buffer, serialized as defined in <em>RFC-4492: Elliptic Curve Cryptography (ECC) Cipher Suites for Transport Layer Security (TLS)</em>. <a href="#a3827a7cf6502530e831e0bb1fcfdd5d8">More...</a><br /></td></tr> <tr class="separator:a3827a7cf6502530e831e0bb1fcfdd5d8"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:a8085ade3e127118aa615f65cb1d393d5"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdsa_8h.html#a8085ade3e127118aa615f65cb1d393d5">mbedtls_ecdsa_read_signature</a> (<a class="el" href="ecdsa_8h.html#a86ad4c743272c83310c20585ec7a182f">mbedtls_ecdsa_context</a> *ctx, const unsigned char *hash, size_t hlen, const unsigned char *sig, size_t slen)</td></tr> <tr class="memdesc:a8085ade3e127118aa615f65cb1d393d5"><td class="mdescLeft"> </td><td class="mdescRight">This function reads and verifies an ECDSA signature. <a href="#a8085ade3e127118aa615f65cb1d393d5">More...</a><br /></td></tr> <tr class="separator:a8085ade3e127118aa615f65cb1d393d5"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:ab909bd06650e761e9fd176a86bd1ce17"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdsa_8h.html#ab909bd06650e761e9fd176a86bd1ce17">mbedtls_ecdsa_genkey</a> (<a class="el" href="ecdsa_8h.html#a86ad4c743272c83310c20585ec7a182f">mbedtls_ecdsa_context</a> *ctx, <a class="el" href="ecp_8h.html#af79e530ea8f8416480f805baa20b1a2d">mbedtls_ecp_group_id</a> gid, int(*f_rng)(void *, unsigned char *, size_t), void *p_rng)</td></tr> <tr class="memdesc:ab909bd06650e761e9fd176a86bd1ce17"><td class="mdescLeft"> </td><td class="mdescRight">This function generates an ECDSA keypair on the given curve. <a href="#ab909bd06650e761e9fd176a86bd1ce17">More...</a><br /></td></tr> <tr class="separator:ab909bd06650e761e9fd176a86bd1ce17"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:a6de8efd872cfe1bc2ee93b4a5584226c"><td class="memItemLeft" align="right" valign="top">int </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdsa_8h.html#a6de8efd872cfe1bc2ee93b4a5584226c">mbedtls_ecdsa_from_keypair</a> (<a class="el" href="ecdsa_8h.html#a86ad4c743272c83310c20585ec7a182f">mbedtls_ecdsa_context</a> *ctx, const <a class="el" href="structmbedtls__ecp__keypair.html">mbedtls_ecp_keypair</a> *key)</td></tr> <tr class="memdesc:a6de8efd872cfe1bc2ee93b4a5584226c"><td class="mdescLeft"> </td><td class="mdescRight">This function sets an ECDSA context from an EC key pair. <a href="#a6de8efd872cfe1bc2ee93b4a5584226c">More...</a><br /></td></tr> <tr class="separator:a6de8efd872cfe1bc2ee93b4a5584226c"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:aca644ee02921388fdc42eb06377f4b62"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdsa_8h.html#aca644ee02921388fdc42eb06377f4b62">mbedtls_ecdsa_init</a> (<a class="el" href="ecdsa_8h.html#a86ad4c743272c83310c20585ec7a182f">mbedtls_ecdsa_context</a> *ctx)</td></tr> <tr class="memdesc:aca644ee02921388fdc42eb06377f4b62"><td class="mdescLeft"> </td><td class="mdescRight">This function initializes an ECDSA context. <a href="#aca644ee02921388fdc42eb06377f4b62">More...</a><br /></td></tr> <tr class="separator:aca644ee02921388fdc42eb06377f4b62"><td class="memSeparator" colspan="2"> </td></tr> <tr class="memitem:a28dd93cb376a51cce39f062858c1c186"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="ecdsa_8h.html#a28dd93cb376a51cce39f062858c1c186">mbedtls_ecdsa_free</a> (<a class="el" href="ecdsa_8h.html#a86ad4c743272c83310c20585ec7a182f">mbedtls_ecdsa_context</a> *ctx)</td></tr> <tr class="memdesc:a28dd93cb376a51cce39f062858c1c186"><td class="mdescLeft"> </td><td class="mdescRight">This function frees an ECDSA context. <a href="#a28dd93cb376a51cce39f062858c1c186">More...</a><br /></td></tr> <tr class="separator:a28dd93cb376a51cce39f062858c1c186"><td class="memSeparator" colspan="2"> </td></tr> </table> <a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2> <div class="textblock"><p>The Elliptic Curve Digital Signature Algorithm (ECDSA). </p> <p>ECDSA is defined in <em>Standards for Efficient Cryptography Group (SECG): SEC1 Elliptic Curve Cryptography</em>. The use of ECDSA for TLS is defined in <em>RFC-4492: Elliptic Curve Cryptography (ECC) Cipher Suites for Transport Layer Security (TLS)</em>. </p> <p class="definition">Definition in file <a class="el" href="ecdsa_8h_source.html">ecdsa.h</a>.</p> </div><h2 class="groupheader">Macro Definition Documentation</h2> <a id="aa9f53b232ef244efb301233d111930dc"></a> <h2 class="memtitle"><span class="permalink"><a href="#aa9f53b232ef244efb301233d111930dc">◆ </a></span>MBEDTLS_DEPRECATED</h2> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">#define MBEDTLS_DEPRECATED</td> </tr> </table> </div><div class="memdoc"> <p class="definition">Definition at line <a class="el" href="ecdsa_8h_source.html#l00209">209</a> of file <a class="el" href="ecdsa_8h_source.html">ecdsa.h</a>.</p> </div> </div> <a id="aeb07d11aef4d847c5cc5cfba49547136"></a> <h2 class="memtitle"><span class="permalink"><a href="#aeb07d11aef4d847c5cc5cfba49547136">◆ </a></span>MBEDTLS_ECDSA_MAX_LEN</h2> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">#define MBEDTLS_ECDSA_MAX_LEN   ( 3 + 2 * ( 3 + <a class="el" href="ecp_8h.html#aba9fdfc8a8dd423182616e5708abf607">MBEDTLS_ECP_MAX_BYTES</a> ) )</td> </tr> </table> </div><div class="memdoc"> <p>The maximal size of an ECDSA signature in Bytes. </p> <p class="definition">Definition at line <a class="el" href="ecdsa_8h_source.html#l00055">55</a> of file <a class="el" href="ecdsa_8h_source.html">ecdsa.h</a>.</p> </div> </div> <h2 class="groupheader">Typedef Documentation</h2> <a id="a86ad4c743272c83310c20585ec7a182f"></a> <h2 class="memtitle"><span class="permalink"><a href="#a86ad4c743272c83310c20585ec7a182f">◆ </a></span>mbedtls_ecdsa_context</h2> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">typedef <a class="el" href="structmbedtls__ecp__keypair.html">mbedtls_ecp_keypair</a> <a class="el" href="ecdsa_8h.html#a86ad4c743272c83310c20585ec7a182f">mbedtls_ecdsa_context</a></td> </tr> </table> </div><div class="memdoc"> <p>The ECDSA context structure. </p> <p class="definition">Definition at line <a class="el" href="ecdsa_8h_source.html#l00060">60</a> of file <a class="el" href="ecdsa_8h_source.html">ecdsa.h</a>.</p> </div> </div> <h2 class="groupheader">Function Documentation</h2> <a id="a28dd93cb376a51cce39f062858c1c186"></a> <h2 class="memtitle"><span class="permalink"><a href="#a28dd93cb376a51cce39f062858c1c186">◆ </a></span>mbedtls_ecdsa_free()</h2> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">void mbedtls_ecdsa_free </td> <td>(</td> <td class="paramtype"><a class="el" href="ecdsa_8h.html#a86ad4c743272c83310c20585ec7a182f">mbedtls_ecdsa_context</a> * </td> <td class="paramname"><em>ctx</em></td><td>)</td> <td></td> </tr> </table> </div><div class="memdoc"> <p>This function frees an ECDSA context. </p> <dl class="params"><dt>Parameters</dt><dd> <table class="params"> <tr><td class="paramname">ctx</td><td>The ECDSA context to free. </td></tr> </table> </dd> </dl> </div> </div> <a id="a6de8efd872cfe1bc2ee93b4a5584226c"></a> <h2 class="memtitle"><span class="permalink"><a href="#a6de8efd872cfe1bc2ee93b4a5584226c">◆ </a></span>mbedtls_ecdsa_from_keypair()</h2> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">int mbedtls_ecdsa_from_keypair </td> <td>(</td> <td class="paramtype"><a class="el" href="ecdsa_8h.html#a86ad4c743272c83310c20585ec7a182f">mbedtls_ecdsa_context</a> * </td> <td class="paramname"><em>ctx</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">const <a class="el" href="structmbedtls__ecp__keypair.html">mbedtls_ecp_keypair</a> * </td> <td class="paramname"><em>key</em> </td> </tr> <tr> <td></td> <td>)</td> <td></td><td></td> </tr> </table> </div><div class="memdoc"> <p>This function sets an ECDSA context from an EC key pair. </p> <dl class="params"><dt>Parameters</dt><dd> <table class="params"> <tr><td class="paramname">ctx</td><td>The ECDSA context to set. </td></tr> <tr><td class="paramname">key</td><td>The EC key to use.</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> 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> </div> </div> <a id="ab909bd06650e761e9fd176a86bd1ce17"></a> <h2 class="memtitle"><span class="permalink"><a href="#ab909bd06650e761e9fd176a86bd1ce17">◆ </a></span>mbedtls_ecdsa_genkey()</h2> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">int mbedtls_ecdsa_genkey </td> <td>(</td> <td class="paramtype"><a class="el" href="ecdsa_8h.html#a86ad4c743272c83310c20585ec7a182f">mbedtls_ecdsa_context</a> * </td> <td class="paramname"><em>ctx</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype"><a class="el" href="ecp_8h.html#af79e530ea8f8416480f805baa20b1a2d">mbedtls_ecp_group_id</a> </td> <td class="paramname"><em>gid</em>, </td> </tr> <tr> <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> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">void * </td> <td class="paramname"><em>p_rng</em> </td> </tr> <tr> <td></td> <td>)</td> <td></td><td></td> </tr> </table> </div><div class="memdoc"> <p>This function generates an ECDSA keypair on the given curve. </p> <dl class="params"><dt>Parameters</dt><dd> <table class="params"> <tr><td class="paramname">ctx</td><td>The ECDSA context to store the keypair in. </td></tr> <tr><td class="paramname">gid</td><td>The elliptic curve to use. One of the various <code>MBEDTLS_ECP_DP_XXX</code> macros depending on configuration. </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> 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> </div> </div> <a id="aca644ee02921388fdc42eb06377f4b62"></a> <h2 class="memtitle"><span class="permalink"><a href="#aca644ee02921388fdc42eb06377f4b62">◆ </a></span>mbedtls_ecdsa_init()</h2> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">void mbedtls_ecdsa_init </td> <td>(</td> <td class="paramtype"><a class="el" href="ecdsa_8h.html#a86ad4c743272c83310c20585ec7a182f">mbedtls_ecdsa_context</a> * </td> <td class="paramname"><em>ctx</em></td><td>)</td> <td></td> </tr> </table> </div><div class="memdoc"> <p>This function initializes an ECDSA context. </p> <dl class="params"><dt>Parameters</dt><dd> <table class="params"> <tr><td class="paramname">ctx</td><td>The ECDSA context to initialize. </td></tr> </table> </dd> </dl> </div> </div> <a id="a8085ade3e127118aa615f65cb1d393d5"></a> <h2 class="memtitle"><span class="permalink"><a href="#a8085ade3e127118aa615f65cb1d393d5">◆ </a></span>mbedtls_ecdsa_read_signature()</h2> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">int mbedtls_ecdsa_read_signature </td> <td>(</td> <td class="paramtype"><a class="el" href="ecdsa_8h.html#a86ad4c743272c83310c20585ec7a182f">mbedtls_ecdsa_context</a> * </td> <td class="paramname"><em>ctx</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">const unsigned char * </td> <td class="paramname"><em>hash</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">size_t </td> <td class="paramname"><em>hlen</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">const unsigned char * </td> <td class="paramname"><em>sig</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">size_t </td> <td class="paramname"><em>slen</em> </td> </tr> <tr> <td></td> <td>)</td> <td></td><td></td> </tr> </table> </div><div class="memdoc"> <p>This function reads and verifies an ECDSA signature. </p> <dl class="params"><dt>Parameters</dt><dd> <table class="params"> <tr><td class="paramname">ctx</td><td>The ECDSA context. </td></tr> <tr><td class="paramname">hash</td><td>The message hash. </td></tr> <tr><td class="paramname">hlen</td><td>The size of the hash. </td></tr> <tr><td class="paramname">sig</td><td>The signature to read and verify. </td></tr> <tr><td class="paramname">slen</td><td>The size of <code>sig</code>.</td></tr> </table> </dd> </dl> <dl class="section note"><dt>Note</dt><dd>If the bitlength of the message hash is larger than the bitlength of the group order, then the hash is truncated as defined in <em>Standards for Efficient Cryptography Group (SECG): SEC1 Elliptic Curve Cryptography</em>, section 4.1.4, step 3.</dd></dl> <dl class="section return"><dt>Returns</dt><dd><code>0</code> on success, <a class="el" href="ecp_8h.html#abcd6ff5c88f83a731383d344b56131f3">MBEDTLS_ERR_ECP_BAD_INPUT_DATA</a> if signature is invalid, <a class="el" href="ecp_8h.html#a49d1dece5c167d28f22702cfc11b9aa1">MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH</a> if there is a valid signature in sig but its length is less than <code>siglen</code>, or an <code>MBEDTLS_ERR_ECP_XXX</code> or <code>MBEDTLS_ERR_MPI_XXX</code> error code on failure for any other reason.</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> </div> </div> <a id="af10f6fda2169862871d0ac07555c8641"></a> <h2 class="memtitle"><span class="permalink"><a href="#af10f6fda2169862871d0ac07555c8641">◆ </a></span>mbedtls_ecdsa_sign()</h2> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">int mbedtls_ecdsa_sign </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> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype"><a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> * </td> <td class="paramname"><em>r</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype"><a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> * </td> <td class="paramname"><em>s</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">const <a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> * </td> <td class="paramname"><em>d</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">const unsigned char * </td> <td class="paramname"><em>buf</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">size_t </td> <td class="paramname"><em>blen</em>, </td> </tr> <tr> <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> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">void * </td> <td class="paramname"><em>p_rng</em> </td> </tr> <tr> <td></td> <td>)</td> <td></td><td></td> </tr> </table> </div><div class="memdoc"> <p>This function computes the ECDSA signature of a previously-hashed message. </p> <dl class="section note"><dt>Note</dt><dd>The deterministic version is usually preferred.</dd></dl> <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">r</td><td>The first output integer. </td></tr> <tr><td class="paramname">s</td><td>The second output integer. </td></tr> <tr><td class="paramname">d</td><td>The private signing key. </td></tr> <tr><td class="paramname">buf</td><td>The message hash. </td></tr> <tr><td class="paramname">blen</td><td>The length of <code>buf</code>. </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>If the bitlength of the message hash is larger than the bitlength of the group order, then the hash is truncated as defined in <em>Standards for Efficient Cryptography Group (SECG): SEC1 Elliptic Curve Cryptography</em>, section 4.1.3, step 5.</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> </div> </div> <a id="a381af8cc9ab0146a4cf1ba5226c81a8f"></a> <h2 class="memtitle"><span class="permalink"><a href="#a381af8cc9ab0146a4cf1ba5226c81a8f">◆ </a></span>mbedtls_ecdsa_sign_det()</h2> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">int mbedtls_ecdsa_sign_det </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> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype"><a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> * </td> <td class="paramname"><em>r</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype"><a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> * </td> <td class="paramname"><em>s</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">const <a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> * </td> <td class="paramname"><em>d</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">const unsigned char * </td> <td class="paramname"><em>buf</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">size_t </td> <td class="paramname"><em>blen</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype"><a class="el" href="md_8h.html#a219313cb40503ec3e34a857ab98b2296">mbedtls_md_type_t</a> </td> <td class="paramname"><em>md_alg</em> </td> </tr> <tr> <td></td> <td>)</td> <td></td><td></td> </tr> </table> </div><div class="memdoc"> <p>This function computes the ECDSA signature of a previously-hashed message, deterministic version. For more information, see <em>RFC-6979: Deterministic Usage of the Digital Signature Algorithm (DSA) and Elliptic Curve Digital Signature Algorithm (ECDSA)</em>. </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">r</td><td>The first output integer. </td></tr> <tr><td class="paramname">s</td><td>The second output integer. </td></tr> <tr><td class="paramname">d</td><td>The private signing key. </td></tr> <tr><td class="paramname">buf</td><td>The message hash. </td></tr> <tr><td class="paramname">blen</td><td>The length of <code>buf</code>. </td></tr> <tr><td class="paramname">md_alg</td><td>The MD algorithm used to hash the message.</td></tr> </table> </dd> </dl> <dl class="section note"><dt>Note</dt><dd>If the bitlength of the message hash is larger than the bitlength of the group order, then the hash is truncated as defined in <em>Standards for Efficient Cryptography Group (SECG): SEC1 Elliptic Curve Cryptography</em>, section 4.1.3, step 5.</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> </div> </div> <a id="a2292032f359fda59a7fd14911cc56f38"></a> <h2 class="memtitle"><span class="permalink"><a href="#a2292032f359fda59a7fd14911cc56f38">◆ </a></span>mbedtls_ecdsa_verify()</h2> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">int mbedtls_ecdsa_verify </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> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">const unsigned char * </td> <td class="paramname"><em>buf</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">size_t </td> <td class="paramname"><em>blen</em>, </td> </tr> <tr> <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> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">const <a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> * </td> <td class="paramname"><em>r</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">const <a class="el" href="structmbedtls__mpi.html">mbedtls_mpi</a> * </td> <td class="paramname"><em>s</em> </td> </tr> <tr> <td></td> <td>)</td> <td></td><td></td> </tr> </table> </div><div class="memdoc"> <p>This function verifies the ECDSA signature of a previously-hashed message. </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">buf</td><td>The message hash. </td></tr> <tr><td class="paramname">blen</td><td>The length of <code>buf</code>. </td></tr> <tr><td class="paramname">Q</td><td>The public key to use for verification. </td></tr> <tr><td class="paramname">r</td><td>The first integer of the signature. </td></tr> <tr><td class="paramname">s</td><td>The second integer of the signature.</td></tr> </table> </dd> </dl> <dl class="section note"><dt>Note</dt><dd>If the bitlength of the message hash is larger than the bitlength of the group order, then the hash is truncated as defined in <em>Standards for Efficient Cryptography Group (SECG): SEC1 Elliptic Curve Cryptography</em>, section 4.1.4, step 3.</dd></dl> <dl class="section return"><dt>Returns</dt><dd><code>0</code> on success, <a class="el" href="ecp_8h.html#abcd6ff5c88f83a731383d344b56131f3">MBEDTLS_ERR_ECP_BAD_INPUT_DATA</a> if signature is invalid, or an <code>MBEDTLS_ERR_ECP_XXX</code> or <code>MBEDTLS_MPI_XXX</code> error code on failure for any other reason.</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> </div> </div> <a id="a76da70289de1f746ad9cce1eadf7b135"></a> <h2 class="memtitle"><span class="permalink"><a href="#a76da70289de1f746ad9cce1eadf7b135">◆ </a></span>mbedtls_ecdsa_write_signature()</h2> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">int mbedtls_ecdsa_write_signature </td> <td>(</td> <td class="paramtype"><a class="el" href="ecdsa_8h.html#a86ad4c743272c83310c20585ec7a182f">mbedtls_ecdsa_context</a> * </td> <td class="paramname"><em>ctx</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype"><a class="el" href="md_8h.html#a219313cb40503ec3e34a857ab98b2296">mbedtls_md_type_t</a> </td> <td class="paramname"><em>md_alg</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">const unsigned char * </td> <td class="paramname"><em>hash</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">size_t </td> <td class="paramname"><em>hlen</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">unsigned char * </td> <td class="paramname"><em>sig</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">size_t * </td> <td class="paramname"><em>slen</em>, </td> </tr> <tr> <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> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">void * </td> <td class="paramname"><em>p_rng</em> </td> </tr> <tr> <td></td> <td>)</td> <td></td><td></td> </tr> </table> </div><div class="memdoc"> <p>This function computes the ECDSA signature and writes it to a buffer, serialized as defined in <em>RFC-4492: Elliptic Curve Cryptography (ECC) Cipher Suites for Transport Layer Security (TLS)</em>. </p> <dl class="section warning"><dt>Warning</dt><dd>It is not thread-safe to use the same context in multiple threads.</dd></dl> <dl class="section note"><dt>Note</dt><dd>The deterministic version is used if <a class="el" href="config_8h.html#adba50fdb786e1708b3360bd04bb77bd1">MBEDTLS_ECDSA_DETERMINISTIC</a> is defined. For more information, see <em>RFC-6979: Deterministic Usage of the Digital Signature Algorithm (DSA) and Elliptic Curve Digital Signature Algorithm (ECDSA)</em>.</dd></dl> <dl class="params"><dt>Parameters</dt><dd> <table class="params"> <tr><td class="paramname">ctx</td><td>The ECDSA context. </td></tr> <tr><td class="paramname">md_alg</td><td>The message digest that was used to hash the message. </td></tr> <tr><td class="paramname">hash</td><td>The message hash. </td></tr> <tr><td class="paramname">hlen</td><td>The length of the hash. </td></tr> <tr><td class="paramname">sig</td><td>The buffer that holds the signature. </td></tr> <tr><td class="paramname">slen</td><td>The length of the signature written. </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>The <code>sig</code> buffer must be at least twice as large as the size of the curve used, plus 9. For example, 73 Bytes if a 256-bit curve is used. A buffer length of <a class="el" href="ecdsa_8h.html#aeb07d11aef4d847c5cc5cfba49547136">MBEDTLS_ECDSA_MAX_LEN</a> is always safe.</dd> <dd> If the bitlength of the message hash is larger than the bitlength of the group order, then the hash is truncated as defined in <em>Standards for Efficient Cryptography Group (SECG): SEC1 Elliptic Curve Cryptography</em>, section 4.1.3, step 5.</dd></dl> <dl class="section return"><dt>Returns</dt><dd><code>0</code> on success, or an <code>MBEDTLS_ERR_ECP_XXX</code>, <code>MBEDTLS_ERR_MPI_XXX</code> or <code>MBEDTLS_ERR_ASN1_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> </div> </div> <a id="a3827a7cf6502530e831e0bb1fcfdd5d8"></a> <h2 class="memtitle"><span class="permalink"><a href="#a3827a7cf6502530e831e0bb1fcfdd5d8">◆ </a></span>mbedtls_ecdsa_write_signature_det()</h2> <div class="memitem"> <div class="memproto"> <table class="memname"> <tr> <td class="memname">int mbedtls_ecdsa_write_signature_det </td> <td>(</td> <td class="paramtype"><a class="el" href="ecdsa_8h.html#a86ad4c743272c83310c20585ec7a182f">mbedtls_ecdsa_context</a> * </td> <td class="paramname"><em>ctx</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">const unsigned char * </td> <td class="paramname"><em>hash</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">size_t </td> <td class="paramname"><em>hlen</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">unsigned char * </td> <td class="paramname"><em>sig</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype">size_t * </td> <td class="paramname"><em>slen</em>, </td> </tr> <tr> <td class="paramkey"></td> <td></td> <td class="paramtype"><a class="el" href="md_8h.html#a219313cb40503ec3e34a857ab98b2296">mbedtls_md_type_t</a> </td> <td class="paramname"><em>md_alg</em> </td> </tr> <tr> <td></td> <td>)</td> <td></td><td></td> </tr> </table> </div><div class="memdoc"> <p>This function computes an ECDSA signature and writes it to a buffer, serialized as defined in <em>RFC-4492: Elliptic Curve Cryptography (ECC) Cipher Suites for Transport Layer Security (TLS)</em>. </p> <p>The deterministic version is defined in <em>RFC-6979: Deterministic Usage of the Digital Signature Algorithm (DSA) and Elliptic Curve Digital Signature Algorithm (ECDSA)</em>.</p> <dl class="section warning"><dt>Warning</dt><dd>It is not thread-safe to use the same context in multiple threads.</dd></dl> <dl class="deprecated"><dt><b><a class="el" href="deprecated.html#_deprecated000007">Deprecated:</a></b></dt><dd>Superseded by <a class="el" href="ecdsa_8h.html#a76da70289de1f746ad9cce1eadf7b135" title="This function computes the ECDSA signature and writes it to a buffer, serialized as defined in RFC-44...">mbedtls_ecdsa_write_signature()</a> in 2.0.0</dd></dl> <dl class="params"><dt>Parameters</dt><dd> <table class="params"> <tr><td class="paramname">ctx</td><td>The ECDSA context. </td></tr> <tr><td class="paramname">hash</td><td>The Message hash. </td></tr> <tr><td class="paramname">hlen</td><td>The length of the hash. </td></tr> <tr><td class="paramname">sig</td><td>The buffer that holds the signature. </td></tr> <tr><td class="paramname">slen</td><td>The length of the signature written. </td></tr> <tr><td class="paramname">md_alg</td><td>The MD algorithm used to hash the message.</td></tr> </table> </dd> </dl> <dl class="section note"><dt>Note</dt><dd>The <code>sig</code> buffer must be at least twice as large as the size of the curve used, plus 9. For example, 73 Bytes if a 256-bit curve is used. A buffer length of <a class="el" href="ecdsa_8h.html#aeb07d11aef4d847c5cc5cfba49547136">MBEDTLS_ECDSA_MAX_LEN</a> is always safe.</dd> <dd> If the bitlength of the message hash is larger than the bitlength of the group order, then the hash is truncated as defined in <em>Standards for Efficient Cryptography Group (SECG): SEC1 Elliptic Curve Cryptography</em>, section 4.1.3, step 5.</dd></dl> <dl class="section return"><dt>Returns</dt><dd><code>0</code> on success, or an <code>MBEDTLS_ERR_ECP_XXX</code>, <code>MBEDTLS_ERR_MPI_XXX</code> or <code>MBEDTLS_ERR_ASN1_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> </div> </div> </div><!-- contents --> <!-- start footer part --> <hr class="footer"/><address class="footer"><small> Generated on Tue Jan 1 2019 18:27:17 for mbed TLS v2.7.8 by  <a href="http://www.doxygen.org/index.html"> <img class="footer" src="doxygen.png" alt="doxygen"/> </a> 1.8.13 </small></address> </body> </html>