Random User-Agent

Author: EthanArbuckle

RedditAPICredentialViewController.h

@@ -1,5 +1,8 @@
-#import <UIKit/UIKit.h>
 #import <WebKit/WebKit.h>
+#import <UIKit/UIKit.h>
+
+#define RANDSTRING  [[NSProcessInfo processInfo] globallyUniqueString]
+#define RANDINT (arc4random() % 9) + 1
 
 @interface RedditAPICredentialViewController : UIViewController <WKNavigationDelegate>
 

RedditAPICredentialViewController.m

@@ -132,7 +132,7 @@ - (void)pageDidUpdate:(WKWebView *)webView {
                                             Array.from(document.getElementsByName('description')).slice(-1)[0].value = \"i'm a fun reddit app\"; \
                                             Array.from(document.getElementsByName('about_url')).slice(-1)[0].value = \"https://google.com\"; \
                                             document.getElementById('redirect_uri').value = \"apollo://reddit-oauth\"; \
-                                            Array.from(document.getElementsByName('name')).slice(-1)[0].value = \"Some app %@\";", [[NSProcessInfo processInfo] globallyUniqueString]];
+                                            Array.from(document.getElementsByName('name')).slice(-1)[0].value = \"Some app %@\";", RANDSTRING];
                 [webView evaluateJavaScript:prefillFormJS completionHandler:nil];
             }];
 

Tweak.m

@@ -55,16 +55,37 @@ static OSStatus SecItemUpdate_replacement(CFDictionaryRef query, CFDictionaryRef
 		});
 	}
 
+	// Reddit API Credentials
 	Class _RDKOAuthCredential = objc_getClass("RDKOAuthCredential");
 	if (_RDKOAuthCredential) {
 
 		Method clientIdMethod = class_getInstanceMethod(_RDKOAuthCredential, sel_registerName("clientIdentifier"));
 		IMP replacementImp = imp_implementationWithBlock(^NSString *(id _self) {
 			return [[NSUserDefaults standardUserDefaults] valueForKey:@"ApolloRedditAPIClientID"];
 		});
+	
 		method_setImplementation(clientIdMethod, replacementImp);
 	}
 
+	// Randomize User-Agent
+	Class _RDKClient = objc_getClass("RDKClient");
+	if (_RDKClient) {
+
+		Method userAgentMethod = class_getInstanceMethod(_RDKClient, sel_registerName("userAgent"));
+		IMP userAgentReplacementImp = imp_implementationWithBlock(^NSString *(id _self) {
+			static dispatch_once_t once;
+			static NSString *newUserAgent;
+			dispatch_once(&once, ^{
+				newUserAgent = [NSString stringWithFormat:@"iOS: com.%@.%@ v%d.%d.%d (by /u/%@)", RANDSTRING, RANDSTRING, RANDINT, RANDINT, RANDINT, RANDSTRING];
+			});
+
+			return newUserAgent;
+		});
+	
+		method_setImplementation(userAgentMethod, userAgentReplacementImp);
+	}
+
+	// Imgur API credentials
 	Class _NSURLSessionConfiguration = objc_getClass("NSURLSessionConfiguration");
 	Method setHeadersMethod = class_getInstanceMethod(_NSURLSessionConfiguration, sel_registerName("setHTTPAdditionalHeaders:"));
 	IMP originalSetHeadersImp = method_getImplementation(setHeadersMethod);
@@ -84,7 +105,7 @@ static OSStatus SecItemUpdate_replacement(CFDictionaryRef query, CFDictionaryRef
 			headers = newHeaders;
 		}
 
-		((void (*)(id, SEL, id))originalSetHeadersImp)(_self, NSSelectorFromString(@"setHTTPAdditionalHeaders:"), headers);
+		((void (*)(id, SEL, id))originalSetHeadersImp)(_self, sel_registerName("setHTTPAdditionalHeaders:"), headers);
 	});
 
 	method_setImplementation(setHeadersMethod, replacementSetHeadersImp);