Custom IPC Authorization

Custom IPC Authorization may be configured to allow you to integrate your own authorization provider. This can be used to link out to other authentication providers or to write your own. The custom authentication scheme allows the authorizer to limit user actions using role based access control.

The authorize function will be invoked on each HTTP request that comes into the Service Gateway, and on each connection opened by IPC clients. By default, the authorize function is simply a global q function in an IPC sidecar called authorize. You can set the environment variable KXI_SG_AUTH_IPC_AUTH_API on the Service Gateway to override the name of this function. The provider should implement an authorize function named in KXI_SG_AUTH_IPC_AUTH_API (default authorize) which accepts a single parameter. The authorize function is responsible for returning a list of roles on success, or an error reason.

External port

Authorization is only applied on the GATEWAY_EXT_QIPC_PORT configured for the Service Gateway.

Environment Variables

The following environmental variables are used to configure the Service Gateway.

name	description	default
KXI_SG_AUTH_IPC_HOST	Controls if custom IPC authorization will be used. Set this to the host of your sidecar	N/A
KXI_SG_AUTH_IPC_PORT	The port number of the sidecar process.	"1234"
KXI_SG_AUTH_IPC_USE_TLS	Instructs if the IPC connection should use TLS.	"false"
KXI_SG_AUTH_IPC_AUTH_API	The symbolic name of the API that will be triggered on the sidecar to authorize requests	"authorize"

localhost

We recommend configuring the authorizer as a process or container side by side with the Service Gateway. This will allow for the fastest transport.

For authorization, a one-shot connection is made to the your provider. If validate user (.z.pw) checks pass, then the authorize function is invoked with dictionary.

.z.pw user validation check

For the validate user check .z.pw, the username and password are set to the basic credentials the client has provided:

h:hopen `:localhost:1234:myuser:pass

# Provide curl a username with --user, or -u to prompt. This gets transformed to the HTTP Header: Authorization Basic and the username and password are base64 encoded and
# [authorization: Basic bXl1c2VyOnBhc3M=]
curl -X POST --user "myuser:pass" "http://localhost:8080/data"

If the Authorization scheme is non-basic, then the username is set to the Authorization scheme, and the password is set to the entire value.

For example, given the header Authorization: Bearer eyJleGFtcGxlIjogImhlbGxvd29ybGQifQ==", the username will be Bearer, and the password will be set to eyJleGFtcGxlIjogImhlbGxvd29ybGQifQ==.

Authorize function

The authorize function is set with KXI_SG_AUTH_IPC_AUTH_API and defaults to authorize.

The following dictionary is provided to the function:

key	description	type
user	The basic username, or the Authorization schema for non-basic HTTP Authorization	symbol
pass	The basic password, or the Authorization headers value for non-basic HTTP Authorization	symbol
uri	The URI for the HTTP request	string
method	The HTTP request method	symbol
headers	All HTTP headers for the request	dict (string values)
body	Optional body for the HTTP request	string

The response may contain the following output keys:

key	description	type
roles	Symbolic list of authorized roles	symbol[]
code	Suggested HTTP response code	integer
error	Error message reason	string

On success, the authorize function is expected to return a dictionary of roles that the request or connection is entitled to:

enlist[`roles]!enlist`insights.query.sql`insights.query.data

The Service Gateway will then handle denying the request if the path requested is not permitted by those roles.

On denial, the authorize function is expected to return an error reason, and suggested HTTP code. If no code is provided, it will default to 401.

`code`error!(404i;"The requested user was not found")

If the authorize function throws an exception, it will be treated as 401 Unauthorized and the reason set to the thrown error.

If some I/O error occurs, the request will be responded to with 500 Internal Server Error and the reason set to the Service Gateway's underlying OS reason.

Sample implementation

To allow access to all administrative APIs, SQL, qSQL, get data, and custom APIs for any request made by an example user bob:

// @param d {dict} Dictionary of user, pass, and HTTP uri, method, headers, body (if relevant)
authorize:{[d]
    :$[`bob ~ d`user;
        enlist[`roles]!enlist `$"insights.query.",/:("admin";"sql";"qsql";"custom";"data");
        `code`error!(403i;"Everyone except bob is forbidden")];
    }

IPC client authorization flow

For an IPC connection, the authorization function is called once upon establishing the client connection, and the roles are checked for each API call made.

The Service Gateway remembers the roles on per connection basis, and will not re-fetch them for the lifetime of that connection.

• Client connects to the service gateway with `:host:port:user:pass
• If validate user check passes, authorize is called on the custom provider
• authorize returns a dictionary of roles that the Service Gateway will cache for the lifetime of the client connection
• The Service Gateway now closes the connection made to the custom provider

Now for the lifetime of the persistent connection:

• Client makes a request for some API
  • For example, getData: h (`.kxi.getData;`startTS`endTS`table!(-0wp;0pw;`trade);()!())
• Roles are checked
  • In this example, .kxi.getData which maps to insights.query.data
• The request is now permitted or denied
• Repeat for the next request

HTTP client authorization flow

For an HTTP Request, the authorization function will be triggered on each request.

• Client makes a request for some path
  • For example: /data
• If validate user check passes, authorize is called on the custom provider
• The service-gateway closes the connection
• Roles are checked
  • For /data which maps to insights.query.data
• The request is now permitted or denied

Sample Kubernetes Deployment

The following sample configuration shows salient configuration for a custom IPC provider as a container beside the Service Gateway in a deployment. Information such as image pull secrets, and other Service Gateway required environmental variables have been omitted for brevity.

Assuming the name of your custom image is custom-ipc-image and the tag is 0.0.0:

---
apiVersion: apps/v1
kind: Deployment
metadata: {}
spec:
  template:
    spec:
     containers:
        - name: sg-gateway
          image: registry/kxi-sg-gw:0.0.0
          env:
            - name: KXI_SG_AUTH_IPC_HOST
              value: "localhost"
            - name: KXI_SG_AUTH_IPC_PORT
              value: "5000"
       - name: auth-provider
         image: registry/custom-ipc-image:0.0.0
         args: ["-p", "5000"]
         ports:
           - name: ipc-port
             containerPort: 5000