> For the complete documentation index, see [llms.txt](https://docs.4everland.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.4everland.org/rpc/json-web-token-jwt.md).

# JSON Web Token (JWT)

## What is JSON Web Token?

JSON Web Token (JWT) is an open, industry standard [RFC 7519](https://tools.ietf.org/html/rfc7519) method for representing claims securely between two parties. You can enable JWT in your API Key and send requests with JWT to ensure only authorized requests are available.

## How to use it?

It's easy to enable JWT and send requests with JWT. You just need to follow the below instructions:

### Generate RSA-256 keys

Generate your own RSA-256 public and private key with 2048 length. Below is the example using [OpenSSL](https://www.openssl.org/).

```Plaintext
# generate rsa key
openssl genrsa -out jwtRSA256-private.pem 2048
openssl rsa -in jwtRSA256-private.pem -pubout -outform PEM -out jwtRSA256-public.pem

```

### Enable JWT in 4EVERLAND RPC

* Login > Dashboard > RPC > API Key > Setting
* Enable the JTW and input the public key generated in previous step.
* You will get the public key ID （uuid) after clicking "Add"

<figure><img src="/files/Gvzh8mTKf1aisNzGgpoT" alt=""><figcaption></figcaption></figure>

Copy ID (uuid) for JWT generation

<figure><img src="/files/uNHhIYRmCn3cBoaDi7YQ" alt=""><figcaption></figcaption></figure>

### Generate the JWT

Once you've enabled the JWT, it's required to add the JWT in all the requests header. Below is the example of generating JWT using <https://jwt.io/>You need HEADER, PAYLOAD, & SIGNATURE to generate a JWT.

### **Header**

| Field | Description                      | Example |
| ----- | -------------------------------- | ------- |
| alg   | The signing algorithm being used | RS256   |
| typ   | The type of the token            | JWT     |

You can use your terminal to encode the header.

```Plaintext
# To encode a header
header=`echo -n '{"alg": "RS256","typ": "JWT","kid": "c6a5278e-ce1d-4f54-b7fa-f8d90f8b5756"}' | base64 | sed s/\+/-/ | sed -E s/=+$//`
```

### **Payload**

| Field | Required | Description                                                                                 | Example                              |
| ----- | -------- | ------------------------------------------------------------------------------------------- | ------------------------------------ |
| uuid  | TRUE     | The ID generated in the previous step in the dashboard.                                     | 00000000-0000-0000-0000-000000000000 |
| exp   | FALSE    | The expiry time. It should be no later than current time + 24 hours. Unix timestamp format. | 1656907527                           |

You can convert a human-readable timestamp to epoch by command below.

```JSON
date -j -f "%Y-%m-%d %H:%M:%S" "2022-07-10 15:58:50" "+%s"
```

Make sure your expiration time is no longer than current time + 24 hours.You can encode your payload by command below.

```Plaintext
#To encode a payload
payload=`echo -n '{"uuid": "00000000-0000-0000-0000-000000000000","exp": "1656907527"}' | base64 | sed s/\+/-/ | sed -E s/=+$//`
```

### **Signature**

To create the signature part you have to take the encoded header, the encoded payload, a secret, the algorithm specified in the header, and sign that.

```Plaintext
# To encode a signature
sig=`echo -n "$header.$payload" | openssl dgst -sha256 -binary -sign jwtRSA256-private.pem  | openssl enc -base64 | tr -d '\n=' | tr -- '+/' '-_'`
```

### **JWT**

Your JWT is the combination of your encoded header.payload.signature.

```Plaintext
# JWT = header.payload.signature
jwt=`echo $header.$payload.$sig`
echo $jwt
```

Verify your jwt by the debugger.

### Send request with JWT

After generating the JWT, you would need to add the JWT as a part of your request header `-H "Authorization: Bearer` entry.

```Plaintext
curl -X POST \
-H "Content-Type: application/json" \
-H "Authorization: Bearer $jwt" \
--data '{"jsonrpc": "2.0", "id": 1, "method": "eth_blockNumber", "params": []}' \
"https://bsc-mainnet.4everland.org/v1/<YOUR-API-KEY>"
```

## What if the JWT is incorrect ?

If you have enabled the JWT but sending requests without JWT or with incorrect JWT, you will receive a http 401 error status code and also the response below.

```Plaintext
{
    "jsonrpc": "2.0",
    "id": 1,
    "error": {
        "code": -40302,
        "message": "Json Web Token parsing failed."
    }
}
```

You should either disable the JWT setting or send requests with correct JWT.

<figure><img src="/files/FSWldc40H3jH4opAgGon" alt=""><figcaption></figcaption></figure>