Module authentication 

Sans-IO MTProto authorization key generation.

Flow

let (req, s1) = authentication::step1()?;
// send req, receive resp (ResPQ)
let (req, s2) = authentication::step2(s1, resp, dc_id)?;
// send req, receive resp (ServerDhParams)
let (req, s3) = authentication::step3(s2, resp)?;
// send req, receive resp (SetClientDhParamsAnswer)
let result = authentication::finish(s3, resp)?;
// on FinishResult::Done(d): d.auth_key is ready
// on FinishResult::Retry{..}: call retry_step3() + finish() up to 5 times

Structs

DhParamsForRetry

Pre-processed server DH parameters retained so that step 3 can be repeated on dh_gen_retry without having to re-decrypt the server response.

Finished

The final output of a successful auth key handshake.

Step1

State after step 1.

Step2

State after step 2.

Step3

State after step 3.

Enums

Error

Errors that can occur during auth key generation.

FinishResult

Result of finish either the handshake is done, or the server wants us to retry step 3 with the auth_key_aux_hash as retry_id.

Functions

finish

Finalise the handshake.

key_for_fingerprint

RSA key by server fingerprint. Includes both production and test DC keys.

retry_step3

Re-run the client DH params generation after a dh_gen_retry response. Feed the dh_params, nonce, server_nonce, new_nonce from FinishResult::Retry and the retry_id (= auth_key_aux_hash).

step1

Generate a req_pq_multi request. Returns the request + opaque state.

step2

Process ResPQ and generate req_DH_params.

step3

Process ServerDhParams into a reusable DhParamsForRetry + send the first set_client_DH_params request.