bolt-relay

bolt-relay

A simple and light-weight secure tunneling application (over SSL) for performing HTTP transactions between systems.

bolt-relay operates via a configuration file and can act as a server, a client to one or more server endpoints, or both at the same time.

Every bolt-relay instance can be configured to run a web server port which effectively enables any application (local or remote) to communicate to the bolt-relay web service and transmit a HTTP request via the bolt instance to any other bolt instances that have secure tunnel established as well as any web applications locally running on the remote bolt instances.

A simple example below:

[application A] -> [bolt 1] -> (SSL tunnel) -> [bolt 2] -> [application B]

All HTTP transaction request is forwarded/relayed to the appropriate destination based on a simple HTTP Header included in every reqeust and is resolved based on CNAME field of the SSL certificate on a given bolt instance:

cloudflash-bolt-target: "some_cname_of_bolt:port"

Going back to the simple example above, in order for application A to communicate with application B, the application A would send a HTTP request which appends an extra HTTP Header to denote the cloudflash-bolt-target to be the cname of bolt 2 along with the port number that application B is listening on.

And that's it. If application B wanted to talk to application A, then it would do the same except it would have the cname of bolt 1 along with port number that application A is listening on as the appropriate target header.

Unlike many other SSL proxy/tunneling applications out there, whether bolt 1 instance was a client to bolt 2 or the other way around does not make any difference to the actual applications that wants to communicate with each other, who is the initiator of the request or acting to respond to requests.

communication establishment sequence

Bolt server functionality: 1.tls/ssl server will be listening for cloudflash-bolt connections on port configured (bolt.json) port. 2.After receiving connection request from bolt client, cert check happens and a new socket has been created for secure channel communication. 3.Bolt Server Maintains list of all connected clients in db. 4.Bolt Server receives requests from controller and based on header data, Cloudflash_Bolt_Target it propagets request to corresponding bolt client.

Bolt client functionality: 1.Initiates ssl connection request with bolt server. 2.Establish secure channel over socket with controller on configured port. 3.Send CNAME and localforwardingports data to bolt server for persistence. 4.Forwards HTTP requests coming on to the configured webservices (cloudflash,salt etc) and send response back to bolt server.

List of Bolt Server APIs*

url = any request path to bolt client like /modules in case of cloudflash.

Verb	URI	Description
POST	/{url}	To configure cloudflash/salt bolt client from bolt server.
GET	/{url}	get list config cloudflash/salt bolt client from bolt server.
PUT	/{url}	To update config cloudflash/salt bolt client from bolt server.
DELETE	/{url}	To delete config cloudflash/salt bolt client from bolt server.

Configure VCG

Verb          URI                     Description
POST        /modules             To configure cloudflash with config requests

Request JSON For all config posts on VCG (cloudflash)

Request
{
    "name": "cloudflash-openvpn",
    "version": "0.1.6"
}

Request JSON - To configure /modules endpoint on VCG

{
"id": "b2cc1a38-4beb-4792-8b01-afd622d056e6",
"description": {
    "name": "cloudflash-openvpn",
    "version": "0.1.6"
},
"status": {
    "installed": true
}
}