JWT Authentication
This HTTP filter can be used to verify JSON Web Token (JWT). It will verify its signature, audiences and issuer. It will also check its time restrictions, such as expiration and nbf (not before) time. If the JWT verification fails, its request will be rejected. If the JWT verification succeeds, its payload can be forwarded to the upstream for further authorization if desired.
JWKS is needed to verify JWT signatures. They can be specified in the filter config or can be fetched remotely from a JWKS server.
Following are supported JWT alg:
ES256, ES384, ES512,
HS256, HS384, HS512,
RS256, RS384, RS512,
PS256, PS384, PS512,
EdDSA
Configuration
This filter should be configured with the type URL
type.googleapis.com/envoy.extensions.filters.http.jwt_authn.v3.JwtAuthentication
.
This HTTP filter config has two fields:
Field
providers
specifies how a JWT should be verified, such as where to extract the token, where to fetch the public key (JWKS) and where to output its payload.Field
rules
specifies matching rules and their requirements. If a request matches a rule, its requirement applies. The requirement specifies which JWT providers should be used.
JwtProvider
JwtProvider specifies how a JWT should be verified. It has the following fields:
issuer
: the principal that issued the JWT, usually a URL or an email address.audiences
: a list of JWT audiences allowed to access. A JWT containing any of these audiences will be accepted. If not specified, the audiences in JWT will not be checked.local_jwks
: fetch JWKS in local data source, either in a local file or embedded in the inline string.remote_jwks
: fetch JWKS from a remote HTTP server, also specify cache duration.forward
: if true, JWT will be forwarded to the upstream.from_headers
: extract JWT from HTTP headers.from_params
: extract JWT from query parameters.from_cookies
: extract JWT from HTTP request cookies.forward_payload_header
: forward the JWT payload in the specified HTTP header.claim_to_headers
: copy JWT claim to HTTP header.jwt_cache_config
: Enables JWT cache, its size can be specified byjwt_cache_size
. Only valid JWTs are cached.
Default Extract Location
If from_headers and from_params is empty, the default location to extract JWT is from HTTP header:
Authorization: Bearer <token>
and query parameter key access_token
as:
/path?access_token=<JWT>
If a request has two tokens, one from the header and the other from the query parameter, all of them must be valid.
The providers field is a map, to map provider_name
to a JwtProvider. The provider_name
must be unique, it is referred by the fields provider_name and provider_name.
Important
If remote_jwks is used, a jwks_cluster
cluster is required to be specified in the field
cluster.
Due to above requirement, OpenID Connect Discovery is not supported since the URL to fetch JWKS is in the response of the discovery. It is not easy to setup a cluster config for a dynamic URL.
Token Extraction from Custom HTTP Headers
If the JWT needs to be extracted in other HTTP header, use from_headers to specify the header name. In addition to the name field, which specifies the HTTP header name, the section can specify an optional value_prefix value, as in:
41 from_headers:
42 - name: x-jwt-header
43 value_prefix: jwt_value
The above will cause the jwt_authn filter to look for the JWT in the x-jwt-header
header, following the tag jwt_value
.
Any non-JWT characters (i.e., anything other than alphanumerics, _, -, and .) will be skipped,
and all following, contiguous, JWT-legal chars will be taken as the JWT.
This means all of the following will return a JWT of eyJFbnZveSI6ICJyb2NrcyJ9.e30.c2lnbmVk
:
x-jwt-header: jwt_value=eyJFbnZveSI6ICJyb2NrcyJ9.e30.c2lnbmVk
x-jwt-header: {"jwt_value": "eyJFbnZveSI6ICJyb2NrcyJ9.e30.c2lnbmVk"}
x-jwt-header: beta:true,jwt_value:"eyJFbnZveSI6ICJyb2NrcyJ9.e30.c2lnbmVk",trace=1234
The header name may be Authorization
.
The value_prefix must match exactly, i.e., case-sensitively. If the value_prefix is not found, the header is skipped, not considered as a source for a JWT.
If there are no JWT-legal characters after the value_prefix, the entire string after it is taken to be the JWT. This is unlikely to succeed; the error will reported by the JWT parser.
Remote JWKS config example
38 providers:
39 provider_name1:
40 issuer: https://example.com
41 audiences:
42 - bookstore_android.apps.googleusercontent.com
43 - bookstore_web.apps.googleusercontent.com
44 remote_jwks:
45 http_uri:
46 uri: https://example.com/jwks.json
47 cluster: example_jwks_cluster
48 timeout: 1s
49 cache_duration: 300s
Above example fetches JWKS from a remote server with URL https://example.com/jwks.json. The token will be extracted from the default extract locations. The token will not be forwarded to upstream. JWT payload will not be added to the request header.
Following cluster example_jwks_cluster is needed to fetch JWKS.
54 clusters:
55 - name: example_jwks_cluster
56 type: STRICT_DNS
57 lb_policy: ROUND_ROBIN
58 load_assignment:
59 cluster_name: example_jwks_cluster
60 endpoints:
61 - lb_endpoints:
62 - endpoint:
63 address:
64 socket_address:
65 address: example_jwks_cluster.example.com
66 port_value: 443
67 transport_socket:
68 name: envoy.transport_sockets.tls
69 typed_config:
70 "@type": type.googleapis.com/envoy.extensions.transport_sockets.tls.v3.UpstreamTlsContext
71 sni: example_jwks_cluster.example.com
Inline JWKS config example
Another config example using inline JWKS:
32 providers:
33 provider_name2:
34 issuer: https://example2.com
35 local_jwks:
36 inline_string: >-
37 {"keys": [
38 {"kty":"RSA",
39 "n": "0vx7agoebGcQSuuPiLJXZptN9nndrQmbXEps2aiAFbWhM78LhWx4cbbfAAtVT86z
40 wu1RK7aPFFxuhDR1L6tSoc_BJECPebWKRXjBZCiFV4n3oknjhMstn64tZ_2W-5JsGY4Hc
41 5n9yBXArwl93lqt7_RN5w6Cf0h4QyQ5v-65YGjQR0_FDW2QvzqY368QQMicAtaSqzs8K
42 JZgnYb9c7d0zgdAZHzu6qMQvRL5hajrn1n91CbOpbISD08qNLyrdkt-bFTWhAI4vMQFh
43 6WeZu0fM4lFd2NcRwr3XPksINHaQ-G_xBniIqbw0Ls1jF44-csFCur-kEgU8awapJzKn
44 qDKgw",
45 "e":"AQAB",
46 "alg":"RS256",
47 "kid":"2011-04-29"}]}
48 from_headers:
49 - name: jwt-assertion
50 forward: true
51 forward_payload_header: x-jwt-payload
Above example uses config inline string to specify JWKS. The JWT will be extracted from HTTP headers as:
jwt-assertion: <JWT>
JWT payload will be added to the request header as following format:
x-jwt-payload: base64url_encoded(jwt_payload_in_JSON)
RequirementRule
RequirementRule has two fields:
Field
match
specifies how a request can be matched; e.g. by HTTP headers, or by query parameters, or by path prefixes.Field
requires
specifies the JWT requirement, e.g. which provider is required.
Important
If a request matches multiple rules, the first matched rule will apply.
If the matched rule has empty
requires
field, JWT verification is not required.If a request doesn’t match any rules, JWT verification is not required.
Single requirement config example
32 providers:
33 jwt_provider1:
34 issuer: https://example.com
35 audiences:
36 - audience1
37 local_jwks:
38 inline_string: >-
39 {"keys": [
40 {"kty":"RSA",
41 "n": "0vx7agoebGcQSuuPiLJXZptN9nndrQmbXEps2aiAFbWhM78LhWx4cbbfAAtVT86z
42 wu1RK7aPFFxuhDR1L6tSoc_BJECPebWKRXjBZCiFV4n3oknjhMstn64tZ_2W-5JsGY4Hc
43 5n9yBXArwl93lqt7_RN5w6Cf0h4QyQ5v-65YGjQR0_FDW2QvzqY368QQMicAtaSqzs8K
44 JZgnYb9c7d0zgdAZHzu6qMQvRL5hajrn1n91CbOpbISD08qNLyrdkt-bFTWhAI4vMQFh
45 6WeZu0fM4lFd2NcRwr3XPksINHaQ-G_xBniIqbw0Ls1jF44-csFCur-kEgU8awapJzKn
46 qDKgw",
47 "e":"AQAB",
48 "alg":"RS256",
49 "kid":"2011-04-29"}]}
50 rules:
51 - match:
52 prefix: /health
53 - match:
54 prefix: /api
55 requires:
56 provider_and_audiences:
57 provider_name: jwt_provider1
58 audiences:
59 - api_audience
60 - match:
61 prefix: /
62 requires:
63 provider_name: jwt_provider1
Above config uses single requirement rule, each rule may have either an empty requirement or a single requirement with one provider name.
Group requirement config example
32 providers:
33 provider1:
34 issuer: https://provider1.com
35 local_jwks:
36 inline_string: >-
37 {"keys": [
38 {"kty":"RSA",
39 "n": "0vx7agoebGcQSuuPiLJXZptN9nndrQmbXEps2aiAFbWhM78LhWx4cbbfAAtVT86z
40 wu1RK7aPFFxuhDR1L6tSoc_BJECPebWKRXjBZCiFV4n3oknjhMstn64tZ_2W-5JsGY4Hc
41 5n9yBXArwl93lqt7_RN5w6Cf0h4QyQ5v-65YGjQR0_FDW2QvzqY368QQMicAtaSqzs8K
42 JZgnYb9c7d0zgdAZHzu6qMQvRL5hajrn1n91CbOpbISD08qNLyrdkt-bFTWhAI4vMQFh
43 6WeZu0fM4lFd2NcRwr3XPksINHaQ-G_xBniIqbw0Ls1jF44-csFCur-kEgU8awapJzKn
44 qDKgw",
45 "e":"AQAB",
46 "alg":"RS256",
47 "kid":"2011-04-29"}]}
48 provider2:
49 issuer: https://provider2.com
50 local_jwks:
51 inline_string: >-
52 {"keys": [
53 {"kty":"RSA",
54 "n": "0vx7agoebGcQSuuPiLJXZptN9nndrQmbXEps2aiAFbWhM78LhWx4cbbfAAtVT86z
55 wu1RK7aPFFxuhDR1L6tSoc_BJECPebWKRXjBZCiFV4n3oknjhMstn64tZ_2W-5JsGY4Hc
56 5n9yBXArwl93lqt7_RN5w6Cf0h4QyQ5v-65YGjQR0_FDW2QvzqY368QQMicAtaSqzs8K
57 JZgnYb9c7d0zgdAZHzu6qMQvRL5hajrn1n91CbOpbISD08qNLyrdkt-bFTWhAI4vMQFh
58 6WeZu0fM4lFd2NcRwr3XPksINHaQ-G_xBniIqbw0Ls1jF44-csFCur-kEgU8awapJzKn
59 qDKgw",
60 "e":"AQAB",
61 "alg":"RS256",
62 "kid":"2011-04-29"}]}
63 rules:
64 - match:
65 prefix: /any
66 requires:
67 requires_any:
68 requirements:
69 - provider_name: provider1
70 - provider_name: provider2
71 - match:
72 prefix: /all
73 requires:
74 requires_all:
75 requirements:
76 - provider_name: provider1
77 - provider_name: provider2
Above config uses more complex group requirements:
The first rule specifies
requires_any
; if any ofprovider1
orprovider2
requirement is satisfied, the request is OK to proceed.The second rule specifies
requires_all
; only if bothprovider1
andprovider2
requirements are satisfied, the request is OK to proceed.
Copy validated JWT claims to HTTP request headers example
If a JWT is valid, you can add some of its claims of type (string, integer, boolean) to a new HTTP header to pass to the upstream. You can specify claims and headers in claim_to_headers field. Nested claims are also supported.
The field claim_to_headers is a repeat of message JWTClaimToHeader which has two fields:
Field
header_name
specifies the name of new http header reserved for jwt claim. If this header is already present with some other value then it will be replaced with the claim value. If the claim value doesn’t exist then this header wouldn’t be available for any other value.Field
claim_name
specifies the claim from the verified JWT.
32 providers:
33 provider_name2:
34 issuer: https://example2.com
35 claim_to_headers:
36 - header_name: x-jwt-claim-sub
37 claim_name: sub
38 - header_name: x-jwt-claim-nested-key
39 claim_name: nested.claim.key
40 - header_name: x-jwt-tenants
41 claim_name: tenants
In this example the tenants claim is an object, therefore the JWT claim (“sub”, “nested.claim.key” and “tenants”) will be added to HTTP headers as following format:
x-jwt-claim-sub: <JWT Claim>
x-jwt-claim-nested-key: <JWT Claim>
x-jwt-tenants: <Base64 encoded JSON JWT Claim>