nitter/src/tid.nim
2025-12-06 17:12:26 -07:00

63 lines
1.7 KiB
Nim

import std/[asyncdispatch, base64, httpclient, random, strutils, sequtils, times]
import nimcrypto
import experimental/parser/tid
randomize()
const defaultKeyword = "obfiowerehiring";
const pairsUrl =
"https://raw.githubusercontent.com/fa0311/x-client-transaction-id-pair-dict/refs/heads/main/pair.json";
var
cachedPairs: seq[TidPair] = @[]
lastCached = 0
# refresh every hour
ttlSec = 60 * 60
proc getPair(): Future[TidPair] {.async.} =
if cachedPairs.len == 0 or int(epochTime()) - lastCached > ttlSec:
lastCached = int(epochTime())
let client = newAsyncHttpClient()
defer: client.close()
let resp = await client.get(pairsUrl)
if resp.status == $Http200:
cachedPairs = parseTidPairs(await resp.body)
return sample(cachedPairs)
proc encodeSha256(text: string): array[32, byte] =
let
data = cast[ptr byte](addr text[0])
dataLen = uint(len(text))
digest = sha256.digest(data, dataLen)
return digest.data
proc encodeBase64[T](data: T): string =
return encode(data).replace("=", "")
proc decodeBase64(data: string): seq[byte] =
return cast[seq[byte]](decode(data))
proc genTid*(path: string): Future[string] {.async.} =
let
pair = await getPair()
timeNow = int(epochTime() - 1682924400)
timeNowBytes = @[
byte(timeNow and 0xff),
byte((timeNow shr 8) and 0xff),
byte((timeNow shr 16) and 0xff),
byte((timeNow shr 24) and 0xff)
]
data = "GET!" & path & "!" & $timeNow & defaultKeyword & pair.animationKey
hashBytes = encodeSha256(data)
keyBytes = decodeBase64(pair.verification)
bytesArr = keyBytes & timeNowBytes & hashBytes[0 ..< 16] & @[3'u8]
randomNum = byte(rand(256))
tid = @[randomNum] & bytesArr.mapIt(it xor randomNum)
return encodeBase64(tid)