<?xml version="1.0"?>

<!--
  Copyright (C) Nginx, Inc.
  -->

<!DOCTYPE module SYSTEM "../../../../dtd/module.dtd">

<module name="Module ngx_http_auth_jwt_module"
        link="/en/docs/http/ngx_http_auth_jwt_module.html"
        lang="en"
        rev="11">

<section id="summary">

<para>
The <literal>ngx_http_auth_jwt_module</literal> module (1.11.3)
implements client authorization by validating the provided
<link url="https://tools.ietf.org/html/rfc7519">JSON Web Token</link> (JWT)
using the specified keys.
JWT claims can be encoded in a
<link url="https://tools.ietf.org/html/rfc7515">JSON Web Signature</link> (JWS)
or
<link url="https://tools.ietf.org/html/rfc7516">JSON Web Encryption</link> (JWE)
(1.19.7) structure.
The module can be used for
<link url="http://openid.net/specs/openid-connect-core-1_0.html">OpenID Connect</link>
authentication.
</para>

<para>
The module may be combined with
other access modules, such as
<link doc="ngx_http_access_module.xml">ngx_http_access_module</link>,
<link doc="ngx_http_auth_basic_module.xml">ngx_http_auth_basic_module</link>,
and
<link doc="ngx_http_auth_request_module.xml">ngx_http_auth_request_module</link>,
via the <link doc="ngx_http_core_module.xml" id="satisfy"/> directive.
</para>

<para>
<note>
This module is available as part of our
<commercial_version>commercial subscription</commercial_version>.
</note>
</para>

</section>


<section id="algorithms" name="Supported Algorithms">

<para>
The module supports the following JSON Web
<link url="https://www.iana.org/assignments/jose/jose.xhtml#web-signature-encryption-algorithms">Algorithms</link>.
</para>

<para>
JWS algorithms:
<list type="bullet">

<listitem>
HS256, HS384, HS512
</listitem>

<listitem>
RS256, RS384, RS512
</listitem>

<listitem>
ES256, ES384, ES512
</listitem>

<listitem>
EdDSA (Ed25519 and Ed448 signatures) (1.15.7)
</listitem>

</list>

<note>
Prior to version 1.13.7,
only HS256, RS256, ES256 algorithms were supported.
</note>
</para>

<para>
JWE content encryption algorithms (1.19.7):
<list type="bullet">

<listitem>
A128CBC-HS256, A192CBC-HS384, A256CBC-HS512
</listitem>

<listitem>
A128GCM, A192GCM, A256GCM
</listitem>

</list>
</para>

<para>
JWE key management algorithms (1.19.9):
<list type="bullet">

<listitem>
A128KW, A192KW, A256KW
</listitem>

<listitem>
A128GCMKW, A192GCMKW, A256GCMKW
</listitem>

<listitem>
dir&mdash;direct use of a shared symmetric key as the content encryption key
</listitem>

</list>
</para>

</section>


<section id="example" name="Example Configuration">

<para>
<example>
location / {
    auth_jwt          "closed site";
    auth_jwt_key_file conf/keys.json;
}
</example>
</para>

</section>


<section id="directives" name="Directives">

<directive name="auth_jwt">
<syntax>
    <value>string</value>
    [<literal>token=</literal><value>$variable</value>] |
    <literal>off</literal></syntax>
<default>off</default>
<context>http</context>
<context>server</context>
<context>location</context>
<context>limit_except</context>

<para>
Enables validation of JSON Web Token.
The specified <value>string</value> is used as a <literal>realm</literal>.
Parameter value can contain variables.
</para>

<para>
The optional <literal>token</literal> parameter specifies a variable
that contains JSON Web Token.
By default, JWT is passed in the <header>Authorization</header> header
as a
<link url="https://tools.ietf.org/html/rfc6750">Bearer Token</link>.
JWT may be also passed as a cookie or a part of a query string:
<example>
auth_jwt "closed site" token=$cookie_auth_token;
</example>
</para>

<para>
The special value <literal>off</literal> cancels the effect
of the <literal>auth_jwt</literal> directive
inherited from the previous configuration level.
</para>

</directive>


<directive name="auth_jwt_claim_set">
<syntax><value>$variable</value> <value>name</value> ...</syntax>
<default/>
<context>http</context>
<appeared-in>1.11.10</appeared-in>

<para>
Sets the <value>variable</value> to a JWT claim parameter
identified by key names.
Name matching starts from the top level of the JSON tree.
For arrays, the variable keeps a list of array elements separated by commas.
<example>
auth_jwt_claim_set $email info e-mail;
auth_jwt_claim_set $job info "job title";
</example>
<note>
Prior to version 1.13.7, only one key name could be specified,
and the result was undefined for arrays.
</note>
</para>

<para>
<note>
Variable values for tokens encrypted with JWE
are available only after decryption which occurs during the
<link doc="../dev/development_guide.xml" id="http_phases">Access</link> phase.
</note>
</para>

</directive>


<directive name="auth_jwt_header_set">
<syntax><value>$variable</value> <value>name</value> ...</syntax>
<default/>
<context>http</context>
<appeared-in>1.11.10</appeared-in>

<para>
Sets the <value>variable</value> to a JOSE header parameter
identified by key names.
Name matching starts from the top level of the JSON tree.
For arrays, the variable keeps a list of array elements separated by commas.
<note>
Prior to version 1.13.7, only one key name could be specified,
and the result was undefined for arrays.
</note>
</para>

</directive>


<directive name="auth_jwt_key_file">
<syntax><value>file</value></syntax>
<default/>
<context>http</context>
<context>server</context>
<context>location</context>
<context>limit_except</context>

<para>
Specifies a <value>file</value> in
<link url="https://tools.ietf.org/html/rfc7517#section-5">JSON Web Key Set</link>
format for validating JWT signature.
Parameter value can contain variables.
</para>

</directive>


<directive name="auth_jwt_key_request">
<syntax><value>uri</value></syntax>
<default/>
<context>http</context>
<context>server</context>
<context>location</context>
<context>limit_except</context>
<appeared-in>1.15.6</appeared-in>

<para>
Allows retrieving a
<link url="https://tools.ietf.org/html/rfc7517#section-5">JSON Web Key Set</link>
file from a subrequest for validating JWT signature and
sets the URI where the subrequest will be sent to.
Parameter value can contain variables.
To avoid validation overhead,
it is recommended to cache the key file:
<example>
proxy_cache_path /data/nginx/cache levels=1 keys_zone=foo:10m;

server {
    ...

    location / {
        auth_jwt             "closed site";
        auth_jwt_key_request /jwks_uri;
    }

    location = /jwks_uri {
        internal;
        proxy_cache foo;
        proxy_pass  http://idp.example.com/keys;
    }
}
</example>
</para>

</directive>


<directive name="auth_jwt_leeway">
<syntax><value>time</value></syntax>
<default>0s</default>
<context>http</context>
<context>server</context>
<context>location</context>
<appeared-in>1.13.10</appeared-in>

<para>
Sets the maximum allowable leeway to compensate
clock skew when verifying the
<link url="https://tools.ietf.org/html/rfc7519#section-4.1.4">exp</link>
and
<link url="https://tools.ietf.org/html/rfc7519#section-4.1.5">nbf</link>
JWT claims.
</para>

</directive>


<directive name="auth_jwt_type">
<syntax><value>signed</value> | <value>encrypted</value></syntax>
<default>signed</default>
<context>http</context>
<context>server</context>
<context>location</context>
<context>limit_except</context>
<appeared-in>1.19.7</appeared-in>

<para>
Specifies which type of JSON Web Token to expect:
JWS (<literal>signed</literal>) or
JWE (<literal>encrypted</literal>).
</para>

</directive>

</section>


<section id="variables" name="Embedded Variables">

<para>
The <literal>ngx_http_auth_jwt_module</literal> module
supports embedded variables:
</para>

<para>
<list type="tag" compact="yes">
<tag-name id="var_jwt_header_"><var>$jwt_header_</var><value>name</value></tag-name>
<tag-desc>
returns the value of a specified
<link url="https://tools.ietf.org/html/rfc7515#section-4">JOSE header</link>
</tag-desc>

<tag-name id="var_jwt_claim_"><var>$jwt_claim_</var><value>name</value></tag-name>
<tag-desc>
returns the value of a specified
<link url="https://tools.ietf.org/html/rfc7519#section-4">JWT claim</link>

<para>
For nested claims and claims including a dot (“.”),
the value of the variable cannot be evaluated;
the <link id="auth_jwt_claim_set"/> directive should be used instead.
</para>

<para>
Variable values for tokens encrypted with JWE
are available only after decryption which occurs during the
<link doc="../dev/development_guide.xml" id="http_phases">Access</link> phase.
</para>
</tag-desc>

</list>
</para>

</section>

</module>