MangaFire: fix mobile useragent requirment & trust all certs (#11065)

* MangaFire: load webResource via okhttp

removes mobile chrome ua dependency

* trust all certs

* convert vrf script to kotlin

taken from: KotatsuApp/kotatsu-parsers

* bump

src/all/mangafire/assets/vrf.js

@@ -1,294 +0,0 @@
-/**
-  Copyright © 2019 W3C and Jeff Carpenter <jeffcarp@chromium.org>
-
-  atob and btoa source code is released under the 3-Clause BSD license.
-*/
- function atob(data) {
-     if (arguments.length === 0) {
-         throw new TypeError("1 argument required, but only 0 present.");
-     }
-
-     const keystr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
-
-     function atobLookup(chr) {
-         const index = keystr.indexOf(chr);
-         // Throw exception if character is not in the lookup string; should not be hit in tests
-         return index < 0 ? undefined : index;
-     }
-
-     data = `${data}`;
-     data = data.replace(/[ \t\n\f\r]/g, "");
-     if (data.length % 4 === 0) {
-         data = data.replace(/==?$/, "");
-     }
-     if (data.length % 4 === 1 || /[^+/0-9A-Za-z]/.test(data)) {
-         return null;
-     }
-     let output = "";
-     let buffer = 0;
-     let accumulatedBits = 0;
-     for (let i = 0; i < data.length; i++) {
-         buffer <<= 6;
-         buffer |= atobLookup(data[i]);
-         accumulatedBits += 6;
-         if (accumulatedBits === 24) {
-         output += String.fromCharCode((buffer & 0xff0000) >> 16);
-         output += String.fromCharCode((buffer & 0xff00) >> 8);
-         output += String.fromCharCode(buffer & 0xff);
-         buffer = accumulatedBits = 0;
-         }
-     }
-     if (accumulatedBits === 12) {
-         buffer >>= 4;
-         output += String.fromCharCode(buffer);
-     } else if (accumulatedBits === 18) {
-         buffer >>= 2;
-         output += String.fromCharCode((buffer & 0xff00) >> 8);
-         output += String.fromCharCode(buffer & 0xff);
-     }
-     return output;
- }
-
- function btoa(s) {
-     if (arguments.length === 0) {
-       throw new TypeError("1 argument required, but only 0 present.");
-     }
-
-     const keystr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
-
-     function btoaLookup(index) {
-         if (index >= 0 && index < 64) {
-         return keystr[index];
-         }
-
-         return undefined;
-     }
-
-     let i;
-     s = `${s}`;
-     for (i = 0; i < s.length; i++) {
-       if (s.charCodeAt(i) > 255) {
-         return null;
-       }
-     }
-     let out = "";
-     for (i = 0; i < s.length; i += 3) {
-       const groupsOfSix = [undefined, undefined, undefined, undefined];
-       groupsOfSix[0] = s.charCodeAt(i) >> 2;
-       groupsOfSix[1] = (s.charCodeAt(i) & 0x03) << 4;
-       if (s.length > i + 1) {
-         groupsOfSix[1] |= s.charCodeAt(i + 1) >> 4;
-         groupsOfSix[2] = (s.charCodeAt(i + 1) & 0x0f) << 2;
-       }
-       if (s.length > i + 2) {
-         groupsOfSix[2] |= s.charCodeAt(i + 2) >> 6;
-         groupsOfSix[3] = s.charCodeAt(i + 2) & 0x3f;
-       }
-       for (let j = 0; j < groupsOfSix.length; j++) {
-         if (typeof groupsOfSix[j] === "undefined") {
-           out += "=";
-         } else {
-           out += btoaLookup(groupsOfSix[j]);
-         }
-       }
-     }
-     return out;
- }
-
-// provided by: @Trung0246 on Github
-
-/**
- * Readable refactor of crc_vrf() with identical output to the original.
- * - Uses byte arrays throughout.
- * - Consolidates repeated transform logic.
- * - Adds clear naming and comments.
- *
- * Example check (must be true):
- * console.log(
- *   crc_vrf("67890@ The quick brown fox jumps over the lazy dog @12345")
- *   === "ZBYeRCjYBk0tkZnKW4kTuWBYw-81e-csvu6v17UY4zchviixt67VJ_tjpFEsOXB-a8X4ZFpDoDbPq8ms-7IyN95vmLVdP5vWSoTAl4ZbIBE8xijci8emrkdEYmArOPMUq5KAc3KEabUzHkNwjBtwvs0fQR7nDpI"
- * );
- */
-
-// Node/browser-friendly base64 helpers
-const atob_ = typeof atob === "function"
-	? atob
-	: (b64) => Buffer.from(b64, "base64").toString("binary");
-
-const btoa_ = typeof btoa === "function"
-	? btoa
-	: (bin) => Buffer.from(bin, "binary").toString("base64");
-
-// Byte helpers
-const toBytes = (str) => Array.from(str, (c) => c.charCodeAt(0) & 0xff);
-const fromBytes = (bytes) => bytes.map((b) => String.fromCharCode(b & 0xff)).join("");
-
-// RC4 over byte arrays (key is a binary string)
-function rc4Bytes(key, input) {
-	const s = Array.from({ length: 256 }, (_, i) => i);
-	let j = 0;
-
-	// KSA
-	for (let i = 0; i < 256; i++) {
-		j = (j + s[i] + key.charCodeAt(i % key.length)) & 0xff;
-		[s[i], s[j]] = [s[j], s[i]];
-	}
-
-	// PRGA
-	const out = new Array(input.length);
-	let i = 0;
-	j = 0;
-	for (let y = 0; y < input.length; y++) {
-		i = (i + 1) & 0xff;
-		j = (j + s[i]) & 0xff;
-		[s[i], s[j]] = [s[j], s[i]];
-		const k = s[(s[i] + s[j]) & 0xff];
-		out[y] = (input[y] ^ k) & 0xff;
-	}
-	return out;
-}
-
-// One generic “step” to remove repeated boilerplate.
-function transform(input, initSeedBytes, prefixKeyString, prefixLen, schedule) {
-	const out = [];
-	for (let i = 0; i < input.length; i++) {
-		if (i < prefixLen) out.push(prefixKeyString.charCodeAt(i) & 0xff);
-
-		out.push(schedule[i % 10]((input[i] ^ initSeedBytes[i % 32]) & 0xff) & 0xff);
-	}
-	return out;
-}
-
-// 8-bit ops
-const add8 = (n) => (c) => (c + n) & 0xff;
-const sub8 = (n) => (c) => (c - n + 256) & 0xff;
-const xor8 = (n) => (c) => (c ^ n) & 0xff;
-const rotl8 = (n) => (c) => ((c << n) | (c >>> (8 - n))) & 0xff;
-
-// Schedules for each step (10 ops each, indexed by i % 10)
-const scheduleC = [
-	sub8(48), sub8(19), xor8(241), sub8(19), add8(223),
-	sub8(19), sub8(170), sub8(19), sub8(48), xor8(8),
-];
-
-const scheduleY = [
-	rotl8(4), add8(223), rotl8(4), xor8(163), sub8(48),
-	add8(82), add8(223), sub8(48), xor8(83), rotl8(4),
-];
-
-const scheduleB = [
-	sub8(19), add8(82), sub8(48), sub8(170), rotl8(4),
-	sub8(48), sub8(170), xor8(8), add8(82), xor8(163),
-];
-
-const scheduleJ = [
-	add8(223), rotl8(4), add8(223), xor8(83), sub8(19),
-	add8(223), sub8(170), add8(223), sub8(170), xor8(83),
-];
-
-const scheduleE = [
-	add8(82), xor8(83), xor8(163), add8(82), sub8(170),
-	xor8(8), xor8(241), add8(82), add8(176), rotl8(4),
-];
-
-function base64UrlEncodeBytes(bytes) {
-	const std = btoa_(fromBytes(bytes));
-	return std.replace(/\+/g, "-").replace(/\//g, "_").replace(/=+$/, "");
-}
-
-function bytesFromBase64(b64) {
-	return toBytes(atob_(b64));
-}
-
-// Constants — grouped logically and left as-is (base64) for clarity.
-const CONST = {
-	rc4Keys: {
-		l: "u8cBwTi1CM4XE3BkwG5Ble3AxWgnhKiXD9Cr279yNW0=",
-		g: "t00NOJ/Fl3wZtez1xU6/YvcWDoXzjrDHJLL2r/IWgcY=",
-		B: "S7I+968ZY4Fo3sLVNH/ExCNq7gjuOHjSRgSqh6SsPJc=",
-		m: "7D4Q8i8dApRj6UWxXbIBEa1UqvjI+8W0UvPH9talJK8=",
-		F: "0JsmfWZA1kwZeWLk5gfV5g41lwLL72wHbam5ZPfnOVE=",
-	},
-	seeds32: {
-		A: "pGjzSCtS4izckNAOhrY5unJnO2E1VbrU+tXRYG24vTo=",
-		V: "dFcKX9Qpu7mt/AD6mb1QF4w+KqHTKmdiqp7penubAKI=",
-		N: "owp1QIY/kBiRWrRn9TLN2CdZsLeejzHhfJwdiQMjg3w=",
-		P: "H1XbRvXOvZAhyyPaO68vgIUgdAHn68Y6mrwkpIpEue8=",
-		k: "2Nmobf/mpQ7+Dxq1/olPSDj3xV8PZkPbKaucJvVckL0=",
-	},
-	prefixKeys: {
-		O: "Rowe+rg/0g==",
-		v: "8cULcnOMJVY8AA==",
-		L: "n2+Og2Gth8Hh",
-		p: "aRpvzH+yoA==",
-		W: "ZB4oBi0=",
-	},
-};
-
-function crc_vrf(input) {
-	// Stage 0: normalize to URI-encoded bytes
-	let bytes = toBytes(encodeURIComponent(input));
-
-	// RC4 1
-	bytes = rc4Bytes(atob_(CONST.rc4Keys.l), bytes);
-
-	// Step C1
-	bytes = transform(
-		bytes,
-		bytesFromBase64(CONST.seeds32.A),
-		atob_(CONST.prefixKeys.O),
-		7,
-		scheduleC
-	);
-
-	// RC4 2
-	bytes = rc4Bytes(atob_(CONST.rc4Keys.g), bytes);
-
-	// Step Y
-	bytes = transform(
-		bytes,
-		bytesFromBase64(CONST.seeds32.V),
-		atob_(CONST.prefixKeys.v),
-		10,
-		scheduleY
-	);
-
-	// RC4 3
-	bytes = rc4Bytes(atob_(CONST.rc4Keys.B), bytes);
-
-	// Step B
-	bytes = transform(
-		bytes,
-		bytesFromBase64(CONST.seeds32.N),
-		atob_(CONST.prefixKeys.L),
-		9,
-		scheduleB
-	);
-
-	// RC4 4
-	bytes = rc4Bytes(atob_(CONST.rc4Keys.m), bytes);
-
-	// Step J
-	bytes = transform(
-		bytes,
-		bytesFromBase64(CONST.seeds32.P),
-		atob_(CONST.prefixKeys.p),
-		7,
-		scheduleJ
-	);
-
-	// RC4 5
-	bytes = rc4Bytes(atob_(CONST.rc4Keys.F), bytes);
-
-	// Step E
-	bytes = transform(
-		bytes,
-		bytesFromBase64(CONST.seeds32.k),
-		atob_(CONST.prefixKeys.W),
-		5,
-		scheduleE
-	);
-
-	// Base64URL
-	return base64UrlEncodeBytes(bytes);
-}

src/all/mangafire/build.gradle

@@ -1,7 +1,7 @@
 ext {
     extName = 'MangaFire'
     extClass = '.MangaFireFactory'
-    extVersionCode = 13
+    extVersionCode = 14
     isNsfw = true
 }
 

src/all/mangafire/src/eu/kanade/tachiyomi/extension/all/mangafire/MangaFire.kt

@@ -11,8 +11,8 @@ import android.webkit.WebView
 import android.webkit.WebViewClient
 import androidx.preference.PreferenceScreen
 import androidx.preference.SwitchPreferenceCompat
-import app.cash.quickjs.QuickJs
 import eu.kanade.tachiyomi.network.GET
+import eu.kanade.tachiyomi.network.await
 import eu.kanade.tachiyomi.source.ConfigurableSource
 import eu.kanade.tachiyomi.source.model.FilterList
 import eu.kanade.tachiyomi.source.model.MangasPage
@@ -24,22 +24,30 @@ import eu.kanade.tachiyomi.util.asJsoup
 import keiyoushi.utils.getPreferencesLazy
 import keiyoushi.utils.parseAs
 import keiyoushi.utils.tryParse
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.runBlocking
 import kotlinx.serialization.Serializable
 import kotlinx.serialization.json.JsonPrimitive
 import kotlinx.serialization.json.int
 import okhttp3.HttpUrl.Companion.toHttpUrl
 import okhttp3.Request
 import okhttp3.Response
+import okhttp3.internal.charset
+import okio.Buffer
 import org.jsoup.Jsoup
 import org.jsoup.nodes.Document
 import org.jsoup.nodes.Element
 import uy.kohesive.injekt.Injekt
 import uy.kohesive.injekt.api.get
-import java.io.ByteArrayInputStream
+import java.security.SecureRandom
+import java.security.cert.X509Certificate
 import java.text.SimpleDateFormat
 import java.util.Locale
 import java.util.concurrent.CountDownLatch
 import java.util.concurrent.TimeUnit
+import javax.net.ssl.SSLContext
+import javax.net.ssl.TrustManager
+import javax.net.ssl.X509TrustManager
 
 class MangaFire(
     override val lang: String,
@@ -52,7 +60,25 @@ class MangaFire(
     override val supportsLatest = true
     private val preferences by getPreferencesLazy()
 
-    override val client = network.cloudflareClient.newBuilder().addInterceptor(ImageInterceptor).build()
+    override val client = network.cloudflareClient.newBuilder()
+        .addInterceptor(ImageInterceptor)
+        .apply {
+            val naiveTrustManager = @SuppressLint("CustomX509TrustManager")
+            object : X509TrustManager {
+                override fun getAcceptedIssuers(): Array<X509Certificate> = emptyArray()
+                override fun checkClientTrusted(certs: Array<X509Certificate>, authType: String) = Unit
+                override fun checkServerTrusted(certs: Array<X509Certificate>, authType: String) = Unit
+            }
+
+            val insecureSocketFactory = SSLContext.getInstance("SSL").apply {
+                val trustAllCerts = arrayOf<TrustManager>(naiveTrustManager)
+                init(null, trustAllCerts, SecureRandom())
+            }.socketFactory
+
+            sslSocketFactory(insecureSocketFactory, naiveTrustManager)
+            hostnameVerifier { _, _ -> true }
+        }
+        .build()
 
     override fun headersBuilder() = super.headersBuilder()
         .add("Referer", "$baseUrl/")
@@ -82,15 +108,6 @@ class MangaFire(
     override fun latestUpdatesParse(response: Response) = searchMangaParse(response)
 
     // =============================== Search ===============================
-    private val vrfScript by lazy {
-        val vrf = this::class.java.getResourceAsStream("/assets/vrf.js")!!
-            .bufferedReader()
-            .readText()
-
-        QuickJs.create().use {
-            it.compile(vrf, "vrf")
-        }
-    }
 
     override fun searchMangaRequest(page: Int, query: String, filters: FilterList): Request {
         val url = baseUrl.toHttpUrl().newBuilder().apply {
@@ -109,10 +126,7 @@ class MangaFire(
             addQueryParameter("page", page.toString())
 
             if (query.isNotBlank()) {
-                val vrf = QuickJs.create().use {
+                val vrf = VrfGenerator.generate(query.trim())
-                    it.execute(vrfScript)
-                    it.evaluate("crc_vrf(\"${query.trim()}\")") as String
-                }
                 addQueryParameter("vrf", vrf)
             }
         }.build()
@@ -255,11 +269,11 @@ class MangaFire(
     override fun pageListParse(response: Response): List<Page> {
         val document = response.asJsoup()
         var ajaxUrl: String? = null
-        var errorMessage: String? = null
 
         val context = Injekt.get<Application>()
         val handler = Handler(Looper.getMainLooper())
         val latch = CountDownLatch(1)
+        val emptyWebViewResponse = WebResourceResponse("text/html", "utf-8", Buffer().inputStream())
         var webView: WebView? = null
 
         handler.post {
@@ -270,12 +284,10 @@ class MangaFire(
                 domStorageEnabled = true
                 databaseEnabled = true
                 blockNetworkImage = true
-                userAgentString = headers["User-Agent"]
             }
 
             webview.webViewClient = object : WebViewClient() {
                 private val ajaxCalls = setOf("ajax/read/chapter", "ajax/read/volume")
-                private val emptyWebViewResponse = WebResourceResponse("text/html", "utf-8", ByteArrayInputStream(" ".toByteArray()))
 
                 override fun shouldInterceptRequest(
                     view: WebView,
@@ -287,14 +299,14 @@ class MangaFire(
                     if (url.host.orEmpty().contains("mfcdn.cc") && url.pathSegments.lastOrNull().orEmpty().contains("js")) {
                         Log.d(name, "allowed: $url")
 
-                        return super.shouldInterceptRequest(view, request)
+                        return fetchWebResource(request)
                     }
 
                     // allow jquery script
                     if (url.host.orEmpty().contains("cloudflare.com") && url.encodedPath.orEmpty().contains("jquery")) {
                         Log.d(name, "allowed: $url")
 
-                        return super.shouldInterceptRequest(view, request)
+                        return fetchWebResource(request)
                     }
 
                     // allow ajax/read calls and intercept ajax/read/chapter or ajax/read/volume
@@ -304,15 +316,13 @@ class MangaFire(
 
                             if (url.getQueryParameter("vrf") != null) {
                                 ajaxUrl = url.toString()
-                            } else {
-                                errorMessage = "vrf not found"
                             }
 
                             latch.countDown()
                         } else {
                             // need to allow other call to ajax/read
                             Log.d(name, "allowed: $url")
-                            return super.shouldInterceptRequest(view, request)
+                            return fetchWebResource(request)
                         }
                     }
 
@@ -333,7 +343,7 @@ class MangaFire(
         if (latch.count == 1L) {
             throw Exception("Timeout getting vrf token")
         } else if (ajaxUrl == null) {
-            throw Exception(errorMessage ?: "Unknown Error")
+            throw Exception("Unable to find vrf token")
         }
 
         return client.newCall(GET(ajaxUrl!!, headers)).execute()
@@ -347,6 +357,31 @@ class MangaFire(
             }
     }
 
+    private fun fetchWebResource(request: WebResourceRequest): WebResourceResponse = runBlocking(Dispatchers.IO) {
+        val okhttpRequest = Request.Builder().apply {
+            url(request.url.toString())
+            headers(headers)
+
+            val skipHeaders = setOf("referer", "user-agent", "sec-ch-ua", "sec-ch-ua-mobile", "sec-ch-ua-platform", "x-requested-with")
+            for ((name, value) in request.requestHeaders) {
+                if (skipHeaders.contains(name.lowercase())) continue
+                addHeader(name, value)
+            }
+        }.build()
+
+        client.newCall(okhttpRequest).await().use { response ->
+            val mediaType = response.body.contentType()
+
+            WebResourceResponse(
+                mediaType?.let { "${it.type}/${it.subtype}" },
+                mediaType?.charset()?.name(),
+                Buffer().readFrom(
+                    response.body.byteStream(),
+                ).inputStream(),
+            )
+        }
+    }
+
     @Serializable
     class PageListDto(private val images: List<List<JsonPrimitive>>) {
         val pages

src/all/mangafire/src/eu/kanade/tachiyomi/extension/all/mangafire/VrfGenerator.kt

@@ -0,0 +1,186 @@
+package eu.kanade.tachiyomi.extension.all.mangafire
+import android.util.Base64
+
+/**
+ * Original script by @Trung0246 on Github
+ */
+object VrfGenerator {
+    private fun atob(data: String): ByteArray = Base64.decode(data, Base64.DEFAULT)
+    private fun btoa(data: ByteArray): String = Base64.encodeToString(data, Base64.DEFAULT)
+
+    private fun rc4(key: ByteArray, input: ByteArray): ByteArray {
+        val s = IntArray(256) { it }
+        var j = 0
+
+        // KSA
+        for (i in 0..255) {
+            j = (j + s[i] + key[i % key.size].toInt().and(0xFF)) and 0xFF
+            val temp = s[i]
+            s[i] = s[j]
+            s[j] = temp
+        }
+
+        // PRGA
+        val output = ByteArray(input.size)
+        var i = 0
+        j = 0
+        for (y in input.indices) {
+            i = (i + 1) and 0xFF
+            j = (j + s[i]) and 0xFF
+            val temp = s[i]
+            s[i] = s[j]
+            s[j] = temp
+            val k = s[(s[i] + s[j]) and 0xFF]
+            output[y] = (input[y].toInt() xor k).toByte()
+        }
+        return output
+    }
+
+    private fun transform(
+        input: ByteArray,
+        initSeedBytes: ByteArray,
+        prefixKeyBytes: ByteArray,
+        prefixLen: Int,
+        schedule: List<(Int) -> Int>,
+    ): ByteArray {
+        val out = mutableListOf<Byte>()
+        for (i in input.indices) {
+            if (i < prefixLen) {
+                out.add(prefixKeyBytes[i])
+            }
+            val transformed = schedule[i % 10](
+                (input[i].toInt() xor initSeedBytes[i % 32].toInt()) and 0xFF,
+            ) and 0xFF
+            out.add(transformed.toByte())
+        }
+        return out.toByteArray()
+    }
+
+    private val scheduleC = listOf<(Int) -> Int>(
+        { c -> (c - 48 + 256) and 0xFF },
+        { c -> (c - 19 + 256) and 0xFF },
+        { c -> (c xor 241) and 0xFF },
+        { c -> (c - 19 + 256) and 0xFF },
+        { c -> (c + 223) and 0xFF },
+        { c -> (c - 19 + 256) and 0xFF },
+        { c -> (c - 170 + 256) and 0xFF },
+        { c -> (c - 19 + 256) and 0xFF },
+        { c -> (c - 48 + 256) and 0xFF },
+        { c -> (c xor 8) and 0xFF },
+    )
+
+    private val scheduleY = listOf<(Int) -> Int>(
+        { c -> ((c shl 4) or (c ushr 4)) and 0xFF },
+        { c -> (c + 223) and 0xFF },
+        { c -> ((c shl 4) or (c ushr 4)) and 0xFF },
+        { c -> (c xor 163) and 0xFF },
+        { c -> (c - 48 + 256) and 0xFF },
+        { c -> (c + 82) and 0xFF },
+        { c -> (c + 223) and 0xFF },
+        { c -> (c - 48 + 256) and 0xFF },
+        { c -> (c xor 83) and 0xFF },
+        { c -> ((c shl 4) or (c ushr 4)) and 0xFF },
+    )
+
+    private val scheduleB = listOf<(Int) -> Int>(
+        { c -> (c - 19 + 256) and 0xFF },
+        { c -> (c + 82) and 0xFF },
+        { c -> (c - 48 + 256) and 0xFF },
+        { c -> (c - 170 + 256) and 0xFF },
+        { c -> ((c shl 4) or (c ushr 4)) and 0xFF },
+        { c -> (c - 48 + 256) and 0xFF },
+        { c -> (c - 170 + 256) and 0xFF },
+        { c -> (c xor 8) and 0xFF },
+        { c -> (c + 82) and 0xFF },
+        { c -> (c xor 163) and 0xFF },
+    )
+
+    private val scheduleJ = listOf<(Int) -> Int>(
+        { c -> (c + 223) and 0xFF },
+        { c -> ((c shl 4) or (c ushr 4)) and 0xFF },
+        { c -> (c + 223) and 0xFF },
+        { c -> (c xor 83) and 0xFF },
+        { c -> (c - 19 + 256) and 0xFF },
+        { c -> (c + 223) and 0xFF },
+        { c -> (c - 170 + 256) and 0xFF },
+        { c -> (c + 223) and 0xFF },
+        { c -> (c - 170 + 256) and 0xFF },
+        { c -> (c xor 83) and 0xFF },
+    )
+
+    private val scheduleE = listOf<(Int) -> Int>(
+        { c -> (c + 82) and 0xFF },
+        { c -> (c xor 83) and 0xFF },
+        { c -> (c xor 163) and 0xFF },
+        { c -> (c + 82) and 0xFF },
+        { c -> (c - 170 + 256) and 0xFF },
+        { c -> (c xor 8) and 0xFF },
+        { c -> (c xor 241) and 0xFF },
+        { c -> (c + 82) and 0xFF },
+        { c -> (c + 176) and 0xFF },
+        { c -> ((c shl 4) or (c ushr 4)) and 0xFF },
+    )
+
+    private val rc4Keys = mapOf(
+        "l" to "u8cBwTi1CM4XE3BkwG5Ble3AxWgnhKiXD9Cr279yNW0=",
+        "g" to "t00NOJ/Fl3wZtez1xU6/YvcWDoXzjrDHJLL2r/IWgcY=",
+        "B" to "S7I+968ZY4Fo3sLVNH/ExCNq7gjuOHjSRgSqh6SsPJc=",
+        "m" to "7D4Q8i8dApRj6UWxXbIBEa1UqvjI+8W0UvPH9talJK8=",
+        "F" to "0JsmfWZA1kwZeWLk5gfV5g41lwLL72wHbam5ZPfnOVE=",
+    )
+
+    private val seeds32 = mapOf(
+        "A" to "pGjzSCtS4izckNAOhrY5unJnO2E1VbrU+tXRYG24vTo=",
+        "V" to "dFcKX9Qpu7mt/AD6mb1QF4w+KqHTKmdiqp7penubAKI=",
+        "N" to "owp1QIY/kBiRWrRn9TLN2CdZsLeejzHhfJwdiQMjg3w=",
+        "P" to "H1XbRvXOvZAhyyPaO68vgIUgdAHn68Y6mrwkpIpEue8=",
+        "k" to "2Nmobf/mpQ7+Dxq1/olPSDj3xV8PZkPbKaucJvVckL0=",
+    )
+
+    private val prefixKeys = mapOf(
+        "O" to "Rowe+rg/0g==",
+        "v" to "8cULcnOMJVY8AA==",
+        "L" to "n2+Og2Gth8Hh",
+        "p" to "aRpvzH+yoA==",
+        "W" to "ZB4oBi0=",
+    )
+
+    fun generate(input: String): String {
+        var bytes = input.toByteArray()
+        // RC4 1
+        bytes = rc4(atob(rc4Keys["l"]!!), bytes)
+
+        // Step C1
+        bytes = transform(bytes, atob(seeds32["A"]!!), atob(prefixKeys["O"]!!), 7, scheduleC)
+
+        // RC4 2
+        bytes = rc4(atob(rc4Keys["g"]!!), bytes)
+
+        // Step Y
+        bytes = transform(bytes, atob(seeds32["V"]!!), atob(prefixKeys["v"]!!), 10, scheduleY)
+
+        // RC4 3
+        bytes = rc4(atob(rc4Keys["B"]!!), bytes)
+
+        // Step B
+        bytes = transform(bytes, atob(seeds32["N"]!!), atob(prefixKeys["L"]!!), 9, scheduleB)
+
+        // RC4 4
+        bytes = rc4(atob(rc4Keys["m"]!!), bytes)
+
+        // Step J
+        bytes = transform(bytes, atob(seeds32["P"]!!), atob(prefixKeys["p"]!!), 7, scheduleJ)
+
+        // RC4 5
+        bytes = rc4(atob(rc4Keys["F"]!!), bytes)
+
+        // Step E
+        bytes = transform(bytes, atob(seeds32["k"]!!), atob(prefixKeys["W"]!!), 5, scheduleE)
+
+        // Base64URL encode
+        return btoa(bytes)
+            .replace("+", "-")
+            .replace("/", "_")
+            .replace("=", "")
+    }
+}