> For the complete documentation index, see [llms.txt](https://docs.enclaive.cloud/nitride/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.enclaive.cloud/nitride/documentation/getting-started/hello-attestation-world.md).

# Hello "attestation" world

Learn to make your first "local" attestation from within the enclaved workload.

**Local attestation** is when a workload inside an enclave retrieves its own security report directly from the hardware. Conversely, **remote attestation** occurs when you direct Nitride to manage the entire attestation and verification process.

## Prerequisites

* Log in as root user to the VM. 
* Install [vHSM CLI](/nitride/documentation/setup/install-nitride.md#installing-the-vhsm-cli).
* Login to the vHSM instance with the [root token](/nitride/documentation/setup/install-nitride.md#installing-vhsm) or any other authentication credential. 

## Step-by-step Guide

### Creating an attestation report

Run the following command in the enclave VM

```bash
vhsm nitride attestation -provider=<provider> generate dump
```

where the attestation `provider` denotes the structure of the attestation report. For details, see [attestation](/nitride/documentation/concepts/attestation.md) concept.

**Example output:**

```json5
{"Version":1,
 "Provider":"aws-sev-snp-raw",
 "Attestation":
 {"Version":1,
  "Product":"Milan",
  "Report":"BAAAAAAAAAAAAAMAAA...",
  "Vlek":"MIIFIzCCAtegAwIBAgIB...",
  "Data":"eyJOb25jZSI6ImR1bXAiLCJEYXRhIjpudWxsfQ=="
}}
```

The report is attested using a Versioned Loaded Endorsement Key (VLEK), an attestation key that AWS loads directly into the Platform Security Processor.

#### Understanding the AWS SEV-SNP Attestation Document

This section explains the structure of an attestation report from an AWS instance using AMD SEV-SNP (Secure Encrypted Virtualization - Secure Nested Paging). The JSON response confirms the integrity and identity of the confidential virtual machine.

#### Key Components

The JSON response is organized into several key-value pairs at the top level.

* `Version`: `1`
  * Indicates the version of the overall attestation format.
* `Provider`: `aws-sev-snp-raw`
  * Identifies the provider as **AWS** and the technology as **SEV-SNP**. The `raw` suffix means the response includes the complete, unmodified AMD hardware report and the VLEK certificate.
* `Data` (Base64 Encoded)
  * This is user-provided data that gets embedded directly into the hardware attestation report to prevent replay attacks.
  * **Decoded:** `{"Nonce":"dump", "Data":null}`
    * **`Nonce`**: A "number used once" provided by the client during the attestation request. Verifying that this nonce is present in the final report confirms the report is fresh and not a replay of a previous one.
    * **`Data`**: An optional field for passing additional user data.
* `Attestation`
  * This contains the core evidence generated by the AMD processor. For more information, see, [Attestation object](#the-attestation-object).
* `Vlek` (Base64 Encoded)
  * A certificate from AWS that endorses the virtual machine's launch environment. For more information, see [Vlek certificate](#vlek-vm-launch-endorsement-key-certificate).

#### Attestation object

This object contains the evidence generated and signed by the AMD CPU's Secure Processor.

* `Version`: `1`
  * The version of the hardware report format itself.
* `Product`: `Milan`
  * Specifies the AMD EPYC processor generation (3rd Gen "Milan").
* `Report` (Base64 Encoded)
  * The cryptographic report from the SEV-SNP hardware. It is signed by the processor and contains crucial integrity measurements:
    * **`MEASUREMENT`**: A cryptographic hash of the initial memory contents of the VM, proving the code has not been tampered with.
    * **`REPORT_DATA`**: Contains the user-provided `Nonce` and `Data` from the top-level field. This binds the hardware report to a specific attestation request.
    * **`POLICY`**: Defines the security policies enforced for the VM (e.g., whether debugging is disabled).
    * **`SIGNATURE`**: The cryptographic signature over the report, created by a key that chains back to AMD's hardware root of trust.

#### &#x20;Vlek (VM Launch Endorsement Key) certificate

The VLEK is a certificate from AWS that adds a layer of trust. Instead of validating the report directly against AMD's public keys, you validate it against this AWS-provided certificate.

* **Purpose**: The VLEK serves as AWS's guarantee that the SEV-SNP environment is legitimate and configured correctly within their infrastructure. It links the hardware-level trust from AMD to the infrastructure-level trust from AWS. The public key in this certificate is used to verify the `Signature` on the `Attestation Report`.
* **Certificate Details (Decoded)**:
  * **`Subject`**: `CN=SEV-VLEK, O=Advanced Micro Devices, Inc., ...`
    * Identifies the certificate as a VLEK for an AMD SEV platform.
  * **`Issuer`**: `CN=SEV-VLEK-Milan, O=Advanced Micro Devices, Inc., ...`
    * Identifies the certificate authority that signed this VLEK, specific to the Milan processor generation.
  * **`Validity`**: `Jun 10 02:30:15 2025 GMT` to `Jun 10 02:30:15 2026 GMT`
    * The time window during which this VLEK is considered valid.
  * **`Extensions`**: These custom fields contain critical metadata.
    * `1.3.6.1.4.1.33136.2.2.1`: Product name (`Milan`).
    * `1.3.6.1.4.1.33136.2.2.2`: AWS endpoint (`cc-eu-west-1.amazonaws.com`), confirming the report originated from the `eu-west-1` region.