Backends Service

The backends service provides a means to manage backends which is where computations run. The service allows the creation, update, viewing and deletion of a backend. The service also manages connections to different backends and monitors them as well as securing the connection with mutual TLS. The service also enables the termination of the manager service running on the backend.

A backend can be described as consisting on manager running on the host, along with agent in a virtual machine in a Trusted Execution Environment.

Creating a Backend

This can be done on the user interface as below:

or by running:

curl -sSiX POST https://prism.ultraviolet.rs/backends -H "Content-Type: application/json" -H "Authorization: Bearer <user_token>" -d @- << EOF
{
  "name": "my dell server",
  "description": "",
  "address": "192.168.100.4"
}
EOF

response:

HTTP/1.1 201 Created
Content-Type: application/json
Location: /backends/fde3263e-70b8-4ce9-9f3c-4a203a0dcdf5
Date: Thu, 02 May 2024 10:15:35 GMT
Content-Length: 0

Updating backend

This can be done on the user interface:

or on curl:

curl -sSiX PUT https://prism.ultraviolet.rs/backends/<backend_id> -H "Content-Type: application/json" -H "Authorization: Bearer <user_token>" -d @- << EOF
{
  "name": "my dell server",
  "description": "new description",
  "address": "192.168.100.4"
}
EOF

response:

HTTP/1.1 200 OK
Content-Type: application/json
Date: Fri, 03 May 2024 20:14:22 GMT
Content-Length: 0

Listing Backends

List of backends is viewable on the ui:

This can be done on curl as shown below:

curl -sSiX GET https://prism.ultraviolet.rs/backends -H "Authorization: Bearer <user_token>"

response:

HTTP/1.1 200 OK
Content-Type: application/json
Date: Fri, 03 May 2024 20:17:03 GMT
Content-Length: 165

{"total":1,"limit":10,"backends":[{"id":"ca219243-0dd4-4e6e-94ad-54fbf3dd8b32","name":"my dell server","description":"some description","address":"192.168.100.4"}]}

View Backend

An individual backend can be viewed on ui where it's details such as address, status, ID, certs and information can be acquired. Certs management is also carried out on this page.

This can be done on curl as below:

curl -sSiX GET https://prism.ultraviolet.rs/backends/<backend_id> -H "Authorization: Bearer <user_token>"

response:

HTTP/1.1 200 OK
Content-Type: application/json
Date: Fri, 03 May 2024 20:19:14 GMT
Content-Length: 129

{"id":"ca219243-0dd4-4e6e-94ad-54fbf3dd8b32","name":"my dell server","description":"some description","address":"192.168.100.4"}

View Backend Information

For a SEV enabled backend, the backend information can be viewed using prism. This information is measured by a Rust script found here. Once compiled and the binary is stored in /build, the backend information can be measured by Prism as shown below.

On the backend page, click the Backend Information button:

If the measurement binary is absent and no measurement is found, an empty measurement file is displayed:

If the measurement is present or measurement is found in the db, the measurement file will be available for download.

The backend_info.json file is useful in cocos for attested TLS, and can be used to verify attestation report. The file is provided to cocos-cli which can add measurement data or host data. The file contains the SnpPolicy and RootOfTrust as shown:

{
  "snp_policy": {
    "policy": 1966081,
    "family_id": "AA==",
    "image_id": "AA==",
    "vmpl": {
      "value": 0
    },
    "minimum_tcb": 1506397780360888800,
    "minimum_launch_tcb": 1506397780360888800,
    "require_author_key": false,
    "measurement": "AA==",
    "host_data": "AA==",
    "report_id_ma": "AA==",
    "chip_id": "GrFqQtRklrsjBslu9pcQ6X4rkftFW1Ar1oT+I4guQ1sVC6qakgSvEtE4P/SLSJ6mHNp0kY0mHnGpvz1Ov+k/w==",
    "minimum_build": 7,
    "minimum_version": "1.55",
    "permit_provisional_firmware": false,
    "require_id_block": false
  },
  "root_of_trust": {
    "product": "Milan",
    "check_crl": true,
    "disallow_network": false
  }
}

Terminate Backend

This is used to disconnect and close the associated backend connection. This is usually triggered when a certificate is revoked while the backend is connected using this certificate or user initiated for any reason. Please note that this action will stop all ongoing computations and stop manager and any running agent.

Manual backend termination can not be done directly on ui, but can be done using the HTTP API:

curl -sSiX GET https://prism.ultraviolet.rs/backends/terminate/<backend_id>/<termination_type> -H "Authorization: Bearer <user_token>"

Termination trype is an integer:

• 0 - Certificate revokation
• 1 - User initiated termination

response:

HTTP/1.1 204 No Content
Content-Type: application/json
Date: Fri, 03 May 2024 20:41:29 GMT

On manager the logs will be as follows:

{"time":"2024-05-03T23:41:29.664410497+03:00","level":"ERROR","msg":"manager service terminated: server requested client termination\nBackend Closed"}
{"time":"2024-05-03T23:41:29.671347637+03:00","level":"ERROR","msg":"Error shutting down tracer provider: context canceled"}

Delete Backend

This removes the backend from the database. This can be done by clicking the delete button on the backend's page as shown:

Alternatively, the backend can be deleted on the backends list page by clicking the trash icon:

This can be done on curl as shown below:

curl -sSiX DELETE https://prism.ultraviolet.rs/backends/<backend_id> -H "Authorization: Bearer <user_token>"

Response:

HTTP/1.1 204 No Content
Content-Type: application/json
Date: Fri, 03 May 2024 20:46:09 GMT