{"id":4329,"date":"2022-12-20T17:48:59","date_gmt":"2022-12-20T20:48:59","guid":{"rendered":"http:\/\/lode.uno\/linux-man\/index.php\/2022\/12\/20\/dnssectrustanchors-d-man5\/"},"modified":"2022-12-20T17:48:59","modified_gmt":"2022-12-20T20:48:59","slug":"dnssectrustanchors-d-man5","status":"publish","type":"post","link":"https:\/\/lode.uno\/linux-man\/2022\/12\/20\/dnssectrustanchors-d-man5\/","title":{"rendered":"DNSSEC&minus;TRUST&minus;ANCHORS.D (man5)"},"content":{"rendered":"<h1 align=\"center\">DNSSEC\u2212TRUST\u2212ANCHORS.D<\/h1>\n<p> <a href=\"#NAME\">NAME<\/a><br \/> <a href=\"#SYNOPSIS\">SYNOPSIS<\/a><br \/> <a href=\"#DESCRIPTION\">DESCRIPTION<\/a><br \/> <a href=\"#POSITIVE TRUST ANCHORS\">POSITIVE TRUST ANCHORS<\/a><br \/> <a href=\"#NEGATIVE TRUST ANCHORS\">NEGATIVE TRUST ANCHORS<\/a><br \/> <a href=\"#SEE ALSO\">SEE ALSO<\/a><br \/> <a href=\"#NOTES\">NOTES<\/a> <\/p>\n<hr>\n<h2>NAME <a name=\"NAME\"><\/a> <\/h2>\n<p style=\"margin-left:11%; margin-top: 1em\">dnssec-trust-anchors.d, systemd.positive, systemd.negative \u2212 DNSSEC trust anchor configuration files<\/p>\n<h2>SYNOPSIS <a name=\"SYNOPSIS\"><\/a> <\/h2>\n<p style=\"margin-left:11%; margin-top: 1em\">\/etc\/dnssec\u2212trust\u2212anchors.d\/*.positive<\/p>\n<p style=\"margin-left:11%; margin-top: 1em\">\/run\/dnssec\u2212trust\u2212anchors.d\/*.positive<\/p>\n<p style=\"margin-left:11%; margin-top: 1em\">\/usr\/lib\/dnssec\u2212trust\u2212anchors.d\/*.positive<\/p>\n<p style=\"margin-left:11%; margin-top: 1em\">\/etc\/dnssec\u2212trust\u2212anchors.d\/*.negative<\/p>\n<p style=\"margin-left:11%; margin-top: 1em\">\/run\/dnssec\u2212trust\u2212anchors.d\/*.negative<\/p>\n<p style=\"margin-left:11%; margin-top: 1em\">\/usr\/lib\/dnssec\u2212trust\u2212anchors.d\/*.negative<\/p>\n<h2>DESCRIPTION <a name=\"DESCRIPTION\"><\/a> <\/h2>\n<p style=\"margin-left:11%; margin-top: 1em\">The DNSSEC trust anchor configuration files define positive and negative trust anchors <b>systemd-resolved.service<\/b>(8) bases DNSSEC integrity proofs on.<\/p>\n<h2>POSITIVE TRUST ANCHORS <a name=\"POSITIVE TRUST ANCHORS\"><\/a> <\/h2>\n<p style=\"margin-left:11%; margin-top: 1em\">Positive trust anchor configuration files contain DNSKEY and DS resource record definitions to use as base for DNSSEC integrity proofs. See <b><font color=\"#0000FF\">RFC 4035, Section 4.4<\/font><\/b> <small><font color=\"#000000\">[1]<\/font><\/small> <font color=\"#000000\">for more information about DNSSEC trust anchors.<\/font><\/p>\n<p style=\"margin-left:11%; margin-top: 1em\"><font color=\"#000000\">Positive trust anchors are read from files with the suffix .positive located in \/etc\/dnssec\u2212trust\u2212anchors.d\/, \/run\/dnssec\u2212trust\u2212anchors.d\/ and \/usr\/lib\/dnssec\u2212trust\u2212anchors.d\/. These directories are searched in the specified order, and a trust anchor file of the same name in an earlier path overrides a trust anchor files in a later path. To disable a trust anchor file shipped in \/usr\/lib\/dnssec\u2212trust\u2212anchors.d\/ it is sufficient to provide an identically\u2212named file in \/etc\/dnssec\u2212trust\u2212anchors.d\/ or \/run\/dnssec\u2212trust\u2212anchors.d\/ that is either empty or a symlink to \/dev\/null (&#8220;masked&#8221;).<\/font><\/p>\n<p style=\"margin-left:11%; margin-top: 1em\"><font color=\"#000000\">Positive trust anchor files are simple text files resembling DNS zone files, as documented in<\/font> <b><font color=\"#0000FF\">RFC 1035, Section 5<\/font><\/b> <small><font color=\"#000000\">[2]<\/font><\/small> <font color=\"#000000\">. One DS or DNSKEY resource record may be listed per line. Empty lines and lines starting with a semicolon (&#8220;;&#8221;) are ignored and considered comments. A DS resource record is specified like in the following example:<\/font><\/p>\n<p style=\"margin-left:17%; margin-top: 1em\"><font color=\"#000000\">. IN DS 19036 8 2 49aac11d7b6f6446702e54a1607371607a1a41855200fd2ce1cdde32f24e8fb5<\/font><\/p>\n<p style=\"margin-left:11%; margin-top: 1em\"><font color=\"#000000\">The first word specifies the domain, use &#8220;.&#8221; for the root domain. The domain may be specified with or without trailing dot, which is considered equivalent. The second word must be &#8220;IN&#8221; the third word &#8220;DS&#8221;. The following words specify the key tag, signature algorithm, digest algorithm, followed by the hex\u2212encoded key fingerprint. See<\/font> <b><font color=\"#0000FF\">RFC 4034, Section 5<\/font><\/b> <small><font color=\"#000000\">[3]<\/font><\/small> <font color=\"#000000\">for details about the precise syntax and meaning of these fields.<\/font><\/p>\n<p style=\"margin-left:11%; margin-top: 1em\"><font color=\"#000000\">Alternatively, DNSKEY resource records may be used to define trust anchors, like in the following example:<\/font><\/p>\n<p style=\"margin-left:17%; margin-top: 1em\"><font color=\"#000000\">. IN DNSKEY 257 3 8 AwEAAagAIKlVZrpC6Ia7gEzahOR+9W29euxhJhVVLOyQbSEW0O8gcCjFFVQUTf6v58fLjwBd0YI0EzrAcQqBGCzh\/RStIoO8g0NfnfL2MTJRkxoXbfDaUeVPQuYEhg37NZWAJQ9VnMVDxP\/VHL496M\/QZxkjf5\/Efucp2gaDX6RS6CXpoY68LsvPVjR0ZSwzz1apAzvN9dlzEheX7ICJBBtuA6G3LQpzW5hOA2hzCTMjJPJ8LbqF6dsV6DoBQzgul0sGIcGOYl7OyQdXfZ57relSQageu+ipAdTTJ25AsRTAoub8ONGcLmqrAmRLKBP1dfwhYB4N7knNnulqQxA+Uk1ihz0=<\/font><\/p>\n<p style=\"margin-left:11%; margin-top: 1em\"><font color=\"#000000\">The first word specifies the domain again, the second word must be &#8220;IN&#8221;, followed by &#8220;DNSKEY&#8221;. The subsequent words encode the DNSKEY flags, protocol and algorithm fields, followed by the key data encoded in Base64. See<\/font> <b><font color=\"#0000FF\">RFC 4034, Section 2<\/font><\/b> <small><font color=\"#000000\">[4]<\/font><\/small> <font color=\"#000000\">for details about the precise syntax and meaning of these fields.<\/font><\/p>\n<p style=\"margin-left:11%; margin-top: 1em\"><font color=\"#000000\">If multiple DS or DNSKEY records are defined for the same domain (possibly even in different trust anchor files), all keys are used and are considered equivalent as base for DNSSEC proofs.<\/font><\/p>\n<p style=\"margin-left:11%; margin-top: 1em\"><font color=\"#000000\">Note that systemd\u2212resolved will automatically use a built\u2212in trust anchor key for the Internet root domain if no positive trust anchors are defined for the root domain. In most cases it is hence unnecessary to define an explicit key with trust anchor files. The built\u2212in key is disabled as soon as at least one trust anchor key for the root domain is defined in trust anchor files.<\/font><\/p>\n<p style=\"margin-left:11%; margin-top: 1em\"><font color=\"#000000\">It is generally recommended to encode trust anchors in DS resource records, rather than DNSKEY resource records.<\/font><\/p>\n<p style=\"margin-left:11%; margin-top: 1em\"><font color=\"#000000\">If a trust anchor specified via a DS record is found revoked it is automatically removed from the trust anchor database for the runtime. See<\/font> <b><font color=\"#0000FF\">RFC 5011<\/font><\/b> <small><font color=\"#000000\">[5]<\/font><\/small> <font color=\"#000000\">for details about revoked trust anchors. Note that systemd\u2212resolved will not update its trust anchor database from DNS servers automatically. Instead, it is recommended to update the resolver software or update the new trust anchor via adding in new trust anchor files.<\/font><\/p>\n<p style=\"margin-left:11%; margin-top: 1em\"><font color=\"#000000\">The current DNSSEC trust anchor for the Internet&#8217;s root domain is available at the<\/font> <b><font color=\"#0000FF\">IANA Trust Anchor and Keys<\/font><\/b> <small><font color=\"#000000\">[6]<\/font><\/small> <font color=\"#000000\">page.<\/font><\/p>\n<h2>NEGATIVE TRUST ANCHORS <a name=\"NEGATIVE TRUST ANCHORS\"><\/a> <\/h2>\n<p style=\"margin-left:11%; margin-top: 1em\"><font color=\"#000000\">Negative trust anchors define domains where DNSSEC validation shall be turned off. Negative trust anchor files are found at the same location as positive trust anchor files, and follow the same overriding rules. They are text files with the .negative suffix. Empty lines and lines whose first character is &#8220;;&#8221; are ignored. Each line specifies one domain name which is the root of a DNS subtree where validation shall be disabled. For example:<\/font><\/p>\n<p style=\"margin-left:17%; margin-top: 1em\"><font color=\"#000000\"># Reverse IPv4 mappings <br \/> 10.in\u2212addr.arpa <br \/> 16.172.in\u2212addr.arpa <br \/> 168.192.in\u2212addr.arpa <br \/> &#8230; <br \/> # Some custom domains <br \/> prod <br \/> stag<\/font><\/p>\n<p style=\"margin-left:11%; margin-top: 1em\"><font color=\"#000000\">Negative trust anchors are useful to support private DNS subtrees that are not referenced from the Internet DNS hierarchy, and not signed.<\/font><\/p>\n<p style=\"margin-left:11%; margin-top: 1em\"><b><font color=\"#0000FF\">RFC 7646<\/font><\/b> <small><font color=\"#000000\">[7]<\/font><\/small> <font color=\"#000000\">for details on negative trust anchors.<\/font><\/p>\n<p style=\"margin-left:11%; margin-top: 1em\"><font color=\"#000000\">If no negative trust anchor files are configured a built\u2212in set of well\u2212known private DNS zone domains is used as negative trust anchors.<\/font><\/p>\n<p style=\"margin-left:11%; margin-top: 1em\"><font color=\"#000000\">It is also possibly to define per\u2212interface negative trust anchors using the <i>DNSSECNegativeTrustAnchors=<\/i> setting in <b>systemd.network<\/b>(5) files.<\/font><\/p>\n<h2>SEE ALSO <a name=\"SEE ALSO\"><\/a> <\/h2>\n<p style=\"margin-left:11%; margin-top: 1em\"><font color=\"#000000\"><b>systemd<\/b>(1), <b>systemd-resolved.service<\/b>(8), <b>resolved.conf<\/b>(5), <b>systemd.network<\/b>(5)<\/font><\/p>\n<h2>NOTES <a name=\"NOTES\"><\/a> <\/h2>\n<table width=\"100%\" border=\"0\" rules=\"none\" frame=\"void\" cellspacing=\"0\" cellpadding=\"0\">\n<tr valign=\"top\" align=\"left\">\n<td width=\"12%\"><\/td>\n<td width=\"3%\">\n<p style=\"margin-top: 1em\"><font color=\"#000000\">1.<\/font><\/p>\n<\/td>\n<td width=\"2%\"><\/td>\n<td width=\"32%\">\n<p style=\"margin-top: 1em\"><font color=\"#000000\">RFC 4035, Section 4.4<\/font><\/p>\n<\/td>\n<td width=\"51%\"> <\/td>\n<\/tr>\n<\/table>\n<p style=\"margin-left:17%;\"><font color=\"#000000\">https:\/\/tools.ietf.org\/html\/rfc4035#section-4.4<\/font><\/p>\n<table width=\"100%\" border=\"0\" rules=\"none\" frame=\"void\" cellspacing=\"0\" cellpadding=\"0\">\n<tr valign=\"top\" align=\"left\">\n<td width=\"12%\"><\/td>\n<td width=\"3%\">\n<p style=\"margin-top: 1em\"><font color=\"#000000\">2.<\/font><\/p>\n<\/td>\n<td width=\"2%\"><\/td>\n<td width=\"29%\">\n<p style=\"margin-top: 1em\"><font color=\"#000000\">RFC 1035, Section 5<\/font><\/p>\n<\/td>\n<td width=\"54%\"> <\/td>\n<\/tr>\n<\/table>\n<p style=\"margin-left:17%;\"><font color=\"#000000\">https:\/\/tools.ietf.org\/html\/rfc1035#section-5<\/font><\/p>\n<table width=\"100%\" border=\"0\" rules=\"none\" frame=\"void\" cellspacing=\"0\" cellpadding=\"0\">\n<tr valign=\"top\" align=\"left\">\n<td width=\"12%\"><\/td>\n<td width=\"3%\">\n<p style=\"margin-top: 1em\"><font color=\"#000000\">3.<\/font><\/p>\n<\/td>\n<td width=\"2%\"><\/td>\n<td width=\"29%\">\n<p style=\"margin-top: 1em\"><font color=\"#000000\">RFC 4034, Section 5<\/font><\/p>\n<\/td>\n<td width=\"54%\"> <\/td>\n<\/tr>\n<\/table>\n<p style=\"margin-left:17%;\"><font color=\"#000000\">https:\/\/tools.ietf.org\/html\/rfc4034#section-5<\/font><\/p>\n<table width=\"100%\" border=\"0\" rules=\"none\" frame=\"void\" cellspacing=\"0\" cellpadding=\"0\">\n<tr valign=\"top\" align=\"left\">\n<td width=\"12%\"><\/td>\n<td width=\"3%\">\n<p style=\"margin-top: 1em\"><font color=\"#000000\">4.<\/font><\/p>\n<\/td>\n<td width=\"2%\"><\/td>\n<td width=\"29%\">\n<p style=\"margin-top: 1em\"><font color=\"#000000\">RFC 4034, Section 2<\/font><\/p>\n<\/td>\n<td width=\"54%\"> <\/td>\n<\/tr>\n<\/table>\n<p style=\"margin-left:17%;\"><font color=\"#000000\">https:\/\/tools.ietf.org\/html\/rfc4034#section-2<\/font><\/p>\n<table width=\"100%\" border=\"0\" rules=\"none\" frame=\"void\" cellspacing=\"0\" cellpadding=\"0\">\n<tr valign=\"top\" align=\"left\">\n<td width=\"12%\"><\/td>\n<td width=\"3%\">\n<p style=\"margin-top: 1em\"><font color=\"#000000\">5.<\/font><\/p>\n<\/td>\n<td width=\"2%\"><\/td>\n<td width=\"12%\">\n<p style=\"margin-top: 1em\"><font color=\"#000000\">RFC 5011<\/font><\/p>\n<\/td>\n<td width=\"71%\"> <\/td>\n<\/tr>\n<\/table>\n<p style=\"margin-left:17%;\"><font color=\"#000000\">https:\/\/tools.ietf.org\/html\/rfc5011<\/font><\/p>\n<table width=\"100%\" border=\"0\" rules=\"none\" frame=\"void\" cellspacing=\"0\" cellpadding=\"0\">\n<tr valign=\"top\" align=\"left\">\n<td width=\"12%\"><\/td>\n<td width=\"3%\">\n<p style=\"margin-top: 1em\"><font color=\"#000000\">6.<\/font><\/p>\n<\/td>\n<td width=\"2%\"><\/td>\n<td width=\"40%\">\n<p style=\"margin-top: 1em\"><font color=\"#000000\">IANA Trust Anchor and Keys<\/font><\/p>\n<\/td>\n<td width=\"43%\"> <\/td>\n<\/tr>\n<\/table>\n<p style=\"margin-left:17%;\"><font color=\"#000000\">https:\/\/data.iana.org\/root-anchors\/root-anchors.xml<\/font><\/p>\n<table width=\"100%\" border=\"0\" rules=\"none\" frame=\"void\" cellspacing=\"0\" cellpadding=\"0\">\n<tr valign=\"top\" align=\"left\">\n<td width=\"12%\"><\/td>\n<td width=\"3%\">\n<p style=\"margin-top: 1em\"><font color=\"#000000\">7.<\/font><\/p>\n<\/td>\n<td width=\"2%\"><\/td>\n<td width=\"12%\">\n<p style=\"margin-top: 1em\"><font color=\"#000000\">RFC 7646<\/font><\/p>\n<\/td>\n<td width=\"71%\"> <\/td>\n<\/tr>\n<\/table>\n<p style=\"margin-left:17%;\"><font color=\"#000000\">https:\/\/tools.ietf.org\/html\/rfc7646<\/font><\/p>\n<hr>\n","protected":false},"excerpt":{"rendered":"<p>  dnssec-trust-anchors.d, systemd.positive, systemd.negative \u2212 DNSSEC trust anchor configuration files <\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[959],"tags":[961,1343,1291],"class_list":["post-4329","post","type-post","status-publish","format-standard","hentry","category-5-formatos-de-ficheros","tag-961","tag-dnssec-trust-anchors","tag-man5"],"gutentor_comment":0,"_links":{"self":[{"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/posts\/4329","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/comments?post=4329"}],"version-history":[{"count":0,"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/posts\/4329\/revisions"}],"wp:attachment":[{"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/media?parent=4329"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/categories?post=4329"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lode.uno\/linux-man\/wp-json\/wp\/v2\/tags?post=4329"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}