<html xmlns="http://www.w3.org/1999/xhtml"><head></head><body><p><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="1" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[1]</anchor-end> <dfn><anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">CA</anchor></dfn> は、<anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">証明書</anchor>の発行元です。</p><section><h1>仕様書</h1><refs xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:"><ul xmlns="http://www.w3.org/1999/xhtml"><li><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="18" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[18]</anchor-end> <cite xml:lang="en">RFC 5280 - Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile</cite>
(<time>2015-02-22 15:44:10 +09:00</time> 版)
<anchor-external xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resScheme="URI" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resParameter="http://tools.ietf.org/html/rfc5280#section-3.2">http://tools.ietf.org/html/rfc5280#section-3.2</anchor-external></li></ul></refs></section><section><h1>分類</h1><figure class="short list"><ul><li><anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">ルートCA</anchor></li><li><anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">下位CA</anchor></li></ul></figure></section><section><h1>Web 用 CA</h1><p><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="13" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[13]</anchor-end> <anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">Web</anchor> 用<anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">証明書</anchor>を発行する <anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">CA</anchor> は、 <anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">CA/Browser Forum</anchor>
の <anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">BR</anchor> に従うのが普通です。</p><p><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="14" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[14]</anchor-end> <anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">BR</anchor> に従わないらしき <anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">CA</anchor> には次のものがあります。<figure class="short list"><ul><li><anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">CAcert</anchor></li></ul></figure></p><p><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="8" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[8]</anchor-end> 他に<anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">オレオレ証明書</anchor>など個人や組織の内部に限定されて運用される <anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">CA</anchor>
があります。</p></section><section><h1>CA 証明書</h1><p><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="17" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[17]</anchor-end> <anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">CA</anchor> の<anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">証明書</anchor>を特に<dfn><rubyb xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">CA証明書<rt xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">CA certificate</rt></rubyb></dfn>といいます。</p><p><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="19" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[19]</anchor-end> <anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">PKIX</anchor> における<anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">CA証明書</anchor>は <anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">RFC 5280</anchor> で規定されています。
<anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">CA証明書</anchor>には、次の種別があります <src xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:10:"><anchor-internal xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="18" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">&gt;&gt;18</anchor-internal></src>。<figure class="short list"><ul><li><anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">相互証明書</anchor></li><li><anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">自己発行証明書</anchor></li><li><anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">自己署名証明書</anchor></li></ul></figure></p><p><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="20" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[20]</anchor-end> <anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">ルートCA</anchor>の<anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">証明書</anchor>を<anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">ルート証明書</anchor>といいます。</p><p><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="21" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[21]</anchor-end> 
<anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">中間証明書</anchor>は<anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">証明書鎖</anchor>に入れてやり取りされます。</p></section><section><h1>実例</h1><figure class="short list"><figcaption><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="16" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[16]</anchor-end> <anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">CA</anchor></figcaption><ul><li><anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">Let's Encrypt</anchor></li><li><anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">CAcert</anchor></li></ul></figure></section><section><h1>文脈</h1><p><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="64" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[64]</anchor-end> <anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">TLS</anchor> <code><anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">CertificateRequest</anchor></code> <anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">メッセージ</anchor>の
<code><anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">certificate_authorities</anchor></code> には、<anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">サーバー</anchor>が受け付ける<anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">CA</anchor>の<anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">DN</anchor>を指定できます。</p></section><section><h1>MIME 型</h1><p><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="7" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[7]</anchor-end> <anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">MIME型</anchor>として <code class="MIME" xml:lang="en"><anchor xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:">application/x-x509-ca-cert</anchor></code>
が使われることがあります。</p></section><section><h1>メモ</h1><p><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="2" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[2]</anchor-end> <cite xml:lang="en-US">Network Security - CAB Forum</cite>
(<time>2015-03-23 23:03:41 +09:00</time> 版)
<anchor-external xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resScheme="URI" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resParameter="https://cabforum.org/network-security/">https://cabforum.org/network-security/</anchor-external></p><figure class="quote"><figcaption><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="3" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[3]</anchor-end> <cite xml:lang="en-US">CA Practices - CAB Forum</cite>
(<time>2015-04-02 12:13:02 +09:00</time> 版)
<anchor-external xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resScheme="URI" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resParameter="https://cabforum.org/ca-practices/">https://cabforum.org/ca-practices/</anchor-external></figcaption><blockquote><p>In addition to the Extended Validation Guidelines and the Baseline Requirements, the CA / Browser Forum has developed statements about the practices of CAs</p></blockquote></figure><p><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="4" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[4]</anchor-end> <cite xml:lang="en">CA:Problematic Practices - MozillaWiki</cite>
(<time>2015-04-02 07:13:46 +09:00</time> 版)
<anchor-external xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resScheme="URI" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resParameter="https://wiki.mozilla.org/CA:Problematic_Practices">https://wiki.mozilla.org/CA:Problematic_Practices</anchor-external></p><p><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="5" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[5]</anchor-end> <cite xml:lang="en">CA:Recommended Practices - MozillaWiki</cite>
(<time>2015-04-02 07:13:29 +09:00</time> 版)
<anchor-external xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resScheme="URI" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resParameter="https://wiki.mozilla.org/CA:Recommended_Practices">https://wiki.mozilla.org/CA:Recommended_Practices</anchor-external></p><p><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="6" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[6]</anchor-end> <cite xml:lang="en">CA:Overview - MozillaWiki</cite>
(<time>2015-04-02 07:20:42 +09:00</time> 版)
<anchor-external xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resScheme="URI" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resParameter="https://wiki.mozilla.org/CA:Overview">https://wiki.mozilla.org/CA:Overview</anchor-external></p><figure class="quote"><figcaption><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="11" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[11]</anchor-end> (<time>2014-11-01 05:54:38 +09:00</time> 版)
<anchor-external xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resScheme="URI" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resParameter="https://cabforum.org/wp-content/uploads/BRv1.2.3.pdf#page=10">https://cabforum.org/wp-content/uploads/BRv1.2.3.pdf#page=10</anchor-external></figcaption><blockquote><p>Certification Authority: An organization that is responsible for the creation, issuance, revocation, and</p><p>management of Certificates. The term applies equally to both Roots CAs and Subordinate CAs. </p></blockquote></figure><figure class="quote"><figcaption><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="12" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[12]</anchor-end> (<time>2014-11-01 05:54:38 +09:00</time> 版)
<anchor-external xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resScheme="URI" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resParameter="https://cabforum.org/wp-content/uploads/BRv1.2.3.pdf#page=46">https://cabforum.org/wp-content/uploads/BRv1.2.3.pdf#page=46</anchor-external></figcaption><blockquote><p>The CA SHALL host test Web pages that allow Application Software Suppliers to test their software with</p><p>Subscriber Certificates that chain up to each publicly trusted Root Certificate. At a minimum, the CA SHALL host</p><p>separate Web pages using Subscriber Certificates that are (i) valid, (ii) revoked, and (iii) expired.</p></blockquote></figure><figure class="quote"><figcaption><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="15" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[15]</anchor-end> (<time>2014-11-01 05:09:16 +09:00</time> 版)
<anchor-external xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resScheme="URI" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resParameter="https://cabforum.org/wp-content/uploads/EV-V1_5_2Libre.pdf#page=41">https://cabforum.org/wp-content/uploads/EV-V1_5_2Libre.pdf#page=41</anchor-external></figcaption><blockquote><p>The CA MUST host test Web pages that allow Application Software Suppliers to test their software with EV</p><p>Certificates that chain up to each EV Root Certificate. At a minimum, the CA MUST host separate Web pages using</p><p>certificates that are (i) valid (ii) revoked and (iii) expired.</p></blockquote></figure><p><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="9" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[9]</anchor-end> <cite>Symantec: Draft Proposal - Google グループ</cite>
(<time>2017-05-08 11:44:05 +09:00</time>)
<anchor-external xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resScheme="URI" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resParameter="https://groups.google.com/forum/#!topic/mozilla.dev.security.policy/IZYmm8zsSKU">https://groups.google.com/forum/#!topic/mozilla.dev.security.policy/IZYmm8zsSKU</anchor-external></p><p><anchor-end xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:anchor="10" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:">[10]</anchor-end> <cite xml:lang="en">Mozilla CA Certificate Store — Mozilla</cite>
(<time>2020-03-27 18:37:57 +09:00</time>)
<anchor-external xmlns="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resScheme="URI" xmlns:a0="urn:x-suika-fam-cx:markup:suikawiki:0:9:" a0:resParameter="https://www.mozilla.org/en-US/about/governance/policies/security-group/certs/">https://www.mozilla.org/en-US/about/governance/policies/security-group/certs/</anchor-external></p></section></body></html>