Module ngx_http_auth_jwt_module

Supported Algorithms
Example Configuration
Directives
     auth_jwt
     auth_jwt_claim_set
     auth_jwt_header_set
     auth_jwt_key_file
     auth_jwt_key_request
     auth_jwt_leeway
     auth_jwt_type
     auth_jwt_require
Embedded Variables

The ngx_http_auth_jwt_module module (1.11.3) implements client authorization by validating the provided JSON Web Token (JWT) using the specified keys. The module supports JSON Web Signature (JWS), JSON Web Encryption (JWE) (1.19.7), and Nested JWT (1.21.0). The module can be used for OpenID Connect authentication.

The module may be combined with other access modules, such as ngx_http_access_module, ngx_http_auth_basic_module, and ngx_http_auth_request_module, via the satisfy directive.

This module is available as part of our commercial subscription.

Supported Algorithms

The module supports the following JSON Web Algorithms.

JWS algorithms:

Prior to version 1.13.7, only HS256, RS256, ES256 algorithms were supported.

JWE content encryption algorithms (1.19.7):

JWE key management algorithms (1.19.9):

Example Configuration

location / {
    auth_jwt          "closed site";
    auth_jwt_key_file conf/keys.json;
}

Directives

Syntax: auth_jwt string [token=$variable] | off;
Default:
auth_jwt off;
Context: http, server, location, limit_except

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

The optional token parameter specifies a variable that contains JSON Web Token. By default, JWT is passed in the “Authorization” header as a Bearer Token. JWT may be also passed as a cookie or a part of a query string:

auth_jwt "closed site" token=$cookie_auth_token;

The special value off cancels the effect of the auth_jwt directive inherited from the previous configuration level.

Syntax: auth_jwt_claim_set $variable name ...;
Default:
Context: http

This directive appeared in version 1.11.10.

Sets the variable 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.

auth_jwt_claim_set $email info e-mail;
auth_jwt_claim_set $job info "job title";

Prior to version 1.13.7, only one key name could be specified, and the result was undefined for arrays.

Variable values for tokens encrypted with JWE are available only after decryption which occurs during the Access phase.

Syntax: auth_jwt_header_set $variable name ...;
Default:
Context: http

This directive appeared in version 1.11.10.

Sets the variable 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.

Prior to version 1.13.7, only one key name could be specified, and the result was undefined for arrays.

Syntax: auth_jwt_key_file file;
Default:
Context: http, server, location, limit_except

Specifies a file in JSON Web Key Set format for validating JWT signature. Parameter value can contain variables.

Several auth_jwt_key_file directives can be specified on the same level (1.21.1):

auth_jwt_key_file conf/keys.json;
auth_jwt_key_file conf/key.jwk;

If at least one of the specified keys cannot be loaded or processed, nginx will return the 500 (Internal Server Error) error.

Syntax: auth_jwt_key_request uri;
Default:
Context: http, server, location, limit_except

This directive appeared in version 1.15.6.

Allows retrieving a JSON Web Key Set 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:

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;
    }
}

Several auth_jwt_key_request directives can be specified on the same level (1.21.1):

auth_jwt_key_request /jwks_uri;
auth_jwt_key_request /jwks2_uri;

If at least one of the specified keys cannot be loaded or processed, nginx will return the 500 (Internal Server Error) error.

Syntax: auth_jwt_leeway time;
Default:
auth_jwt_leeway 0s;
Context: http, server, location

This directive appeared in version 1.13.10.

Sets the maximum allowable leeway to compensate clock skew when verifying the exp and nbf JWT claims.

Syntax: auth_jwt_type signed | encrypted | nested;
Default:
auth_jwt_type signed;
Context: http, server, location, limit_except

This directive appeared in version 1.19.7.

Specifies which type of JSON Web Token to expect: JWS (signed), JWE (encrypted), or signed and then encrypted Nested JWT (nested) (1.21.0).

Syntax: auth_jwt_require value ...;
Default:
Context: http, server, location, limit_except

This directive appeared in version 1.21.2.

Defines additional conditions for JWT validation. The value can contain text, variables, and their combination. The authentication will succeed only if all the values are not empty and are not equal to “0”.

map $jwt_claim_iss $valid_jwt_iss {
    "good" 1;
}
...

auth_jwt_require $valid_jwt_iss;

Embedded Variables

The ngx_http_auth_jwt_module module supports embedded variables:

$jwt_header_name
returns the value of a specified JOSE header
$jwt_claim_name
returns the value of a specified JWT claim

For nested claims and claims including a dot (“.”), the value of the variable cannot be evaluated; the auth_jwt_claim_set directive should be used instead.

Variable values for tokens encrypted with JWE are available only after decryption which occurs during the Access phase.

$jwt_payload
returns the decrypted top-level payload of nested or encrypted tokens (1.21.2). For nested tokens returns the enclosed JWS token. For encrypted tokens returns JSON with claims.