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diff --git a/doc/src/sgml/html/auth-username-maps.html b/doc/src/sgml/html/auth-username-maps.html new file mode 100644 index 0000000..9e9d9c8 --- /dev/null +++ b/doc/src/sgml/html/auth-username-maps.html @@ -0,0 +1,102 @@ +<?xml version="1.0" encoding="UTF-8" standalone="no"?> +<!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/html; charset=UTF-8" /><title>21.2. User Name Maps</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="auth-pg-hba-conf.html" title="21.1. The pg_hba.conf File" /><link rel="next" href="auth-methods.html" title="21.3. Authentication Methods" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">21.2. User Name Maps</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="auth-pg-hba-conf.html" title="21.1. The pg_hba.conf File">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="client-authentication.html" title="Chapter 21. Client Authentication">Up</a></td><th width="60%" align="center">Chapter 21. Client Authentication</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 15.5 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="auth-methods.html" title="21.3. Authentication Methods">Next</a></td></tr></table><hr /></div><div class="sect1" id="AUTH-USERNAME-MAPS"><div class="titlepage"><div><div><h2 class="title" style="clear: both">21.2. User Name Maps</h2></div></div></div><a id="id-1.6.8.9.2" class="indexterm"></a><p> + When using an external authentication system such as Ident or GSSAPI, + the name of the operating system user that initiated the connection + might not be the same as the database user (role) that is to be used. + In this case, a user name map can be applied to map the operating system + user name to a database user. To use user name mapping, specify + <code class="literal">map</code>=<em class="replaceable"><code>map-name</code></em> + in the options field in <code class="filename">pg_hba.conf</code>. This option is + supported for all authentication methods that receive external user names. + Since different mappings might be needed for different connections, + the name of the map to be used is specified in the + <em class="replaceable"><code>map-name</code></em> parameter in <code class="filename">pg_hba.conf</code> + to indicate which map to use for each individual connection. + </p><p> + User name maps are defined in the ident map file, which by default is named + <code class="filename">pg_ident.conf</code><a id="id-1.6.8.9.4.2" class="indexterm"></a> + and is stored in the + cluster's data directory. (It is possible to place the map file + elsewhere, however; see the <a class="xref" href="runtime-config-file-locations.html#GUC-IDENT-FILE">ident_file</a> + configuration parameter.) + The ident map file contains lines of the general form: +</p><pre class="synopsis"> +<em class="replaceable"><code>map-name</code></em> <em class="replaceable"><code>system-username</code></em> <em class="replaceable"><code>database-username</code></em> +</pre><p> + Comments, whitespace and line continuations are handled in the same way as in + <code class="filename">pg_hba.conf</code>. The + <em class="replaceable"><code>map-name</code></em> is an arbitrary name that will be used to + refer to this mapping in <code class="filename">pg_hba.conf</code>. The other + two fields specify an operating system user name and a matching + database user name. The same <em class="replaceable"><code>map-name</code></em> can be + used repeatedly to specify multiple user-mappings within a single map. + </p><p> + There is no restriction regarding how many database users a given + operating system user can correspond to, nor vice versa. Thus, entries + in a map should be thought of as meaning <span class="quote">“<span class="quote">this operating system + user is allowed to connect as this database user</span>”</span>, rather than + implying that they are equivalent. The connection will be allowed if + there is any map entry that pairs the user name obtained from the + external authentication system with the database user name that the + user has requested to connect as. + </p><p> + If the <em class="replaceable"><code>system-username</code></em> field starts with a slash (<code class="literal">/</code>), + the remainder of the field is treated as a regular expression. + (See <a class="xref" href="functions-matching.html#POSIX-SYNTAX-DETAILS" title="9.7.3.1. Regular Expression Details">Section 9.7.3.1</a> for details of + <span class="productname">PostgreSQL</span>'s regular expression syntax.) The regular + expression can include a single capture, or parenthesized subexpression, + which can then be referenced in the <em class="replaceable"><code>database-username</code></em> + field as <code class="literal">\1</code> (backslash-one). This allows the mapping of + multiple user names in a single line, which is particularly useful for + simple syntax substitutions. For example, these entries +</p><pre class="programlisting"> +mymap /^(.*)@mydomain\.com$ \1 +mymap /^(.*)@otherdomain\.com$ guest +</pre><p> + will remove the domain part for users with system user names that end with + <code class="literal">@mydomain.com</code>, and allow any user whose system name ends with + <code class="literal">@otherdomain.com</code> to log in as <code class="literal">guest</code>. + </p><div class="tip"><h3 class="title">Tip</h3><p> + Keep in mind that by default, a regular expression can match just part of + a string. It's usually wise to use <code class="literal">^</code> and <code class="literal">$</code>, as + shown in the above example, to force the match to be to the entire + system user name. + </p></div><p> + The <code class="filename">pg_ident.conf</code> file is read on start-up and + when the main server process receives a + <span class="systemitem">SIGHUP</span><a id="id-1.6.8.9.8.3" class="indexterm"></a> + signal. If you edit the file on an + active system, you will need to signal the postmaster + (using <code class="literal">pg_ctl reload</code>, calling the SQL function + <code class="function">pg_reload_conf()</code>, or using <code class="literal">kill + -HUP</code>) to make it re-read the file. + </p><p> + The system view + <a class="link" href="view-pg-ident-file-mappings.html" title="54.10. pg_ident_file_mappings"><code class="structname">pg_ident_file_mappings</code></a> + can be helpful for pre-testing changes to the + <code class="filename">pg_ident.conf</code> file, or for diagnosing problems if + loading of the file did not have the desired effects. Rows in the view with + non-null <code class="structfield">error</code> fields indicate problems in the + corresponding lines of the file. + </p><p> + A <code class="filename">pg_ident.conf</code> file that could be used in + conjunction with the <code class="filename">pg_hba.conf</code> file in <a class="xref" href="auth-pg-hba-conf.html#EXAMPLE-PG-HBA.CONF" title="Example 21.1. Example pg_hba.conf Entries">Example 21.1</a> is shown in <a class="xref" href="auth-username-maps.html#EXAMPLE-PG-IDENT.CONF" title="Example 21.2. An Example pg_ident.conf File">Example 21.2</a>. In this example, anyone + logged in to a machine on the 192.168 network that does not have the + operating system user name <code class="literal">bryanh</code>, <code class="literal">ann</code>, or + <code class="literal">robert</code> would not be granted access. Unix user + <code class="literal">robert</code> would only be allowed access when he tries to + connect as <span class="productname">PostgreSQL</span> user <code class="literal">bob</code>, not + as <code class="literal">robert</code> or anyone else. <code class="literal">ann</code> would + only be allowed to connect as <code class="literal">ann</code>. User + <code class="literal">bryanh</code> would be allowed to connect as either + <code class="literal">bryanh</code> or as <code class="literal">guest1</code>. + </p><div class="example" id="EXAMPLE-PG-IDENT.CONF"><p class="title"><strong>Example 21.2. An Example <code class="filename">pg_ident.conf</code> File</strong></p><div class="example-contents"><pre class="programlisting"> +# MAPNAME SYSTEM-USERNAME PG-USERNAME + +omicron bryanh bryanh +omicron ann ann +# bob has user name robert on these machines +omicron robert bob +# bryanh can also connect as guest1 +omicron bryanh guest1 +</pre></div></div><br class="example-break" /></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="auth-pg-hba-conf.html" title="21.1. The pg_hba.conf File">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="client-authentication.html" title="Chapter 21. Client Authentication">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="auth-methods.html" title="21.3. Authentication Methods">Next</a></td></tr><tr><td width="40%" align="left" valign="top">21.1. 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