feat(Reddit is Fun - Spoof client): Spoof the user agent

2023-08-03 00:58:11 +02:00
parent 9426b28dcc
commit 9ac0ed477a
11 changed files with 167 additions and 102 deletions
@@ -0,0 +1,88 @@
+package app.revanced.patches.reddit.customclients
+
+import android.os.Environment
+import app.revanced.extensions.toErrorResult
+import app.revanced.patcher.data.BytecodeContext
+import app.revanced.patcher.fingerprint.method.impl.MethodFingerprint
+import app.revanced.patcher.fingerprint.method.impl.MethodFingerprintResult
+import app.revanced.patcher.patch.*
+import java.io.File
+
+abstract class AbstractSpoofClientPatch(
+    private val redirectUri: String,
+    private val options: SpoofClientOptionsContainer,
+    private val clientIdFingerprints: List<MethodFingerprint>,
+    private val userAgentFingerprints: List<MethodFingerprint>? = null,
+) : BytecodePatch(buildList {
+    addAll(clientIdFingerprints)
+    userAgentFingerprints?.let(::addAll)
+}) {
+    override fun execute(context: BytecodeContext): PatchResult {
+        if (options.clientId == null) {
+            // Ensure device runs Android.
+            try {
+                Class.forName("android.os.Environment")
+            } catch (e: ClassNotFoundException) {
+                return PatchResultError("No client ID provided")
+            }
+
+            File(Environment.getExternalStorageDirectory(), "reddit_client_id_revanced.txt").also {
+                if (it.exists()) return@also
+
+                val error = """
+                    In order to use this patch, you need to provide a client ID.
+                    You can do this by creating a file at ${it.absolutePath} with the client ID as its content.
+                    Alternatively, you can provide the client ID using patch options.
+                    
+                    You can get your client ID from https://www.reddit.com/prefs/apps.
+                    The application type has to be "Installed app" and the redirect URI has to be set to "$redirectUri".
+                """.trimIndent()
+
+                return PatchResultError(error)
+            }.let { options.clientId = it.readText().trim() }
+        }
+
+        fun List<MethodFingerprint>?.executePatch(
+            patch: List<MethodFingerprintResult>.(BytecodeContext) -> PatchResult
+        ) {
+            when (val result = this?.map { it.result ?: throw it.toErrorResult() }?.patch(context)) {
+                is PatchResultError -> throw result
+            }
+        }
+
+        clientIdFingerprints.executePatch { patchClientId(context) }
+        userAgentFingerprints.executePatch { patchUserAgent(context) }
+
+        return PatchResultSuccess()
+    }
+
+    /**
+     * Patch the client ID. The fingerprints are guaranteed to be in the same order as in [clientIdFingerprints].
+     *
+     * @param context The current [BytecodeContext].
+     *
+     */
+    abstract fun List<MethodFingerprintResult>.patchClientId(context: BytecodeContext): PatchResult
+
+    /**
+     * Patch the user agent. The fingerprints are guaranteed to be in the same order as in [userAgentFingerprints].
+     *
+     * @param context The current [BytecodeContext].
+     */
+    // Not every client needs to patch the user agent.
+    open fun List<MethodFingerprintResult>.patchUserAgent(context: BytecodeContext): PatchResult =
+        PatchResultSuccess()
+
+    companion object Options {
+        open class SpoofClientOptionsContainer : OptionsContainer() {
+            var clientId by option(
+                PatchOption.StringOption(
+                    "client-id",
+                    null,
+                    "OAuth client ID",
+                    "The Reddit OAuth client ID."
+                )
+            )
+        }
+    }
+}