[THREESCALE-10708] JWT Parser Policy

[tkan145]

What

Fix https://issues.redhat.com/browse/THREESCALE-10708

This is mostly a rename of oidc_authentication policy with an extra bit a logic on top to handle potential conflict with existing service configured with OIDC.

See #904 (comment)

Verification steps

1. Check out this branch and build a new runtime-image

make runtime-image IMAGE_NAME=apicast-test

2. Move into dev-environments

cd dev-environments/keycloak-env

3. Modify apicast-config.json as follow

diff --git a/dev-environments/keycloak-env/apicast-config.json b/dev-environments/keycloak-env/apicast-config.json 
index 071296cd..d5ca17ca 100644                                                                                    
--- a/dev-environments/keycloak-env/apicast-config.json                                                            
+++ b/dev-environments/keycloak-env/apicast-config.json                                                            
@@ -84,10 +84,10 @@                                                                                                
         },                                                                                                        
         "policy_chain": [                                                                                         
           {                                                                                                       
-            "name": "token_introspection",                                                                        
-            "version": "builtin",                                                                                 
+            "name": "apicast.policy.jwt_parser",                                                                  
             "configuration": {                                                                                    
-              "auth_type": "use_3scale_oidc_issuer_endpoint"                                                      
+              "issuer_endpoint": "http://keycloak:8080/realms/basic",                                             
+              "required": true                                                                                    
             }                                                                                                     
           },                                                                                                      
           {                                                                                                       

4. Start gateway

make gateway IMAGE_NAME=apicast-test

5. In another terminal seed keycloak-data

make keycloak-data

6. Send request

export ACCESS_TOKEN=$(make token)

curl -v --resolve stg.example.com:8080:127.0.0.1 -H "Authorization: Bearer ${ACCESS_TOKEN}" "http://stg.example.com:8080"

7. Check APIcast log for the following message

[warn] 19#19: *2 jwt_parser.lua:49: check_compatible(): jwt_parser is incompatible with OIDC authentication mode, requestID=10c3fa9952859b03221ee7085fcaa6b3, client: 172.18.0.1, server: _, request: "GET / HTTP/1.1", host: "stg.example.com:8080"                                                                                                                                                         

8. Stop the gateway

CTRL-C

9. Edit apicast-config.json

diff --git a/dev-environments/keycloak-env/apicast-config.json b/dev-environments/keycloak-env/apicast-config.json                          
index 071296cd..ec3d6532 100644                                                                                                             
--- a/dev-environments/keycloak-env/apicast-config.json                                                                                     
+++ b/dev-environments/keycloak-env/apicast-config.json                                                                                     
@@ -2,7 +2,7 @@                                                                                                                             
   "services": [                                                                                                                            
     {                                                                                                                                      
       "id": 2,                                                                                                                             
-      "backend_version": "oauth",                                                                                                          
+      "backend_version": "1",                                                                                                              
       "account_id": 2,                                                                                                                     
       "name": "API",                                                                                                                       
       "description": null,                                                                                                                 
@@ -63,7 +63,7 @@                                                                                                                           
         "apicast_configuration_driven": true,                                                                                              
         "oidc_issuer_endpoint": "http://oidc-issuer-for-3scale:oidc-issuer-for-3scale-secret@keycloak:8080/realms/basic",                  
         "lock_version": 4,                                                                                                                 
-        "authentication_method": "oidc",                                                                                                   
+        "authentication_method": "1",                                                                                                      
         "oidc_issuer_type": "keycloak",                                                                                                    
         "error_headers_limits_exceeded": "text/plain; charset=us-ascii",                                                                   
         "error_status_limits_exceeded": 429,                                                                                               
@@ -84,10 +84,23 @@                                                                                                                         
         },                                                                                                                                 
         "policy_chain": [                                                                                                                  
           {                                                                                                                                
-            "name": "token_introspection",                                                                                                 
-            "version": "builtin",                                                                                                          
+            "name": "apicast.policy.jwt_parser",                                                                                           
+            "configuration": {                                                                                                             
+              "issuer_endpoint": "http://keycloak:8080/realms/basic",                                                                      
+              "required": true                                                                                                             
+            }                                                                                                                              
+          },                                                                                                                               
+          {                                                                                                                                
+            "name": "apicast.policy.jwt_claim_check",                                                                                      
             "configuration": {                                                                                                             
-              "auth_type": "use_3scale_oidc_issuer_endpoint"                                                                               
+              "rules" : [{                                                                                                                 
+                  "operations": [                                                                                                          
+                    {"op": "==", "jwt_claim": "{{realm_access.roles| first}}", "jwt_claim_type": "liquid", "value": "default-roles-basic"} 
+                  ],                                                                                                                       
+                  "combine_op": "and",                                                                                                     
+                  "methods": ["GET"],                                                                                                      
+                  "resource": "/"                                                                                                          
+              }]                                                                                                                           
             }                                                                                                                              
           },                                                                                                                               
           {                                                                                                                                

10. Send a request without Authorization header. You should see 403 Forbidden

curl -v --resolve stg.example.com:8080:127.0.0.1  "http://stg.example.com:8080/?user_key=foo" 

11. Retrieve access token and send another request

export ACCESS_TOKEN=$(make token)

curl -v --resolve stg.example.com:8080:127.0.0.1 -H "Authorization: Bearer ${ACCESS_TOKEN}" "http://stg.example.com:8080/?user_key=foo"

You should now see HTTP/1.1 200 OK