I implemented a Network Extension in the macOS, use NETransparentProxyProvider. After installing and enabling it, I implemented a UDP client to test its. I found that the UDP client failed to send the data successfully (via sendto, and it returned a success), and when using Wireshark to capture the network data packet, I still couldn't see this UDP data packet.
The code for Network Extension is like this:
@interface MyTransparentProxyProvider : NETransparentProxyProvider @end @implementation MyTransparentProxyProvider - (void)startProxyWithOptions:(NSDictionary *)options completionHandler:(void (^)(NSError *))completionHandler { NETransparentProxyNetworkSettings *objSettings = [[NETransparentProxyNetworkSettings alloc] initWithTunnelRemoteAddress:@"127.0.0.1"]; // included rules NENetworkRule *objIncludedNetworkRule = [[NENetworkRule alloc] initWithRemoteNetwork:nil remotePrefix:0 localNetwork:nil localPrefix:0 protocol:NENetworkRuleProtocolAny direction:NETrafficDirectionOutbound]; NSMutableArray<NENetworkRule *> *arrIncludedNetworkRules = [NSMutableArray array]; [arrIncludedNetworkRules addObject:objIncludedNetworkRule]; objSettings.includedNetworkRules = arrIncludedNetworkRules; // apply [self setTunnelNetworkSettings:objSettings completionHandler: ^(NSError * _Nullable error) { // TODO } ]; if (completionHandler != nil) completionHandler(nil); } - (BOOL)handleNewFlow:(NEAppProxyFlow *)flow { if (flow == nil) return NO; char szProcPath[PROC_PIDPATHINFO_MAXSIZE] = {0}; audit_token_t *lpAuditToken = (audit_token_t*)flow.metaData.sourceAppAuditToken.bytes; if (lpAuditToken != NULL) { proc_pidpath_audittoken(lpAuditToken, szProcPath, sizeof(szProcPath)); } if ([flow isKindOfClass:[NEAppProxyTCPFlow class]]) { NWHostEndpoint *objRemoteEndpoint = (NWHostEndpoint *)((NEAppProxyTCPFlow *)flow).remoteEndpoint; LOG("-MyTransparentProxyProvider handleNewFlow:] TCP flow! Process: (%d)%s, %s Remote: %s:%s, %s", lpAuditToken != NULL ? audit_token_to_pid(*lpAuditToken) : -1, flow.metaData.sourceAppSigningIdentifier != nil ? [flow.metaData.sourceAppSigningIdentifier UTF8String] : "", szProcPath, objRemoteEndpoint != nil ? (objRemoteEndpoint.hostname != nil ? [objRemoteEndpoint.hostname UTF8String] : "") : "", objRemoteEndpoint != nil ? (objRemoteEndpoint.port != nil ? [objRemoteEndpoint.port UTF8String] : "") : "", ((NEAppProxyTCPFlow *)flow).remoteHostname != nil ? [((NEAppProxyTCPFlow *)flow).remoteHostname UTF8String] : "" ); } else if ([flow isKindOfClass:[NEAppProxyUDPFlow class]]) { NSString *strLocalEndpoint = [NSString stringWithFormat:@"%@", ((NEAppProxyUDPFlow *)flow).localEndpoint]; LOG("-[MyTransparentProxyProvider handleNewFlow:] UDP flow! Process: (%d)%s, %s LocalEndpoint: %s", lpAuditToken != NULL ? audit_token_to_pid(*lpAuditToken) : -1, flow.metaData.sourceAppSigningIdentifier != nil ? [flow.metaData.sourceAppSigningIdentifier UTF8String] : "", szProcPath, strLocalEndpoint != nil ? [strLocalEndpoint UTF8String] : "" ); } else { LOG("-[MyTransparentProxyProvider handleNewFlow:] Unknown flow! Process: (%d)%s, %s", lpAuditToken != NULL ? audit_token_to_pid(*lpAuditToken) : -1, flow.metaData.sourceAppSigningIdentifier != nil ? [flow.metaData.sourceAppSigningIdentifier UTF8String] : "", szProcPath ); } return NO; } @end
The following methods can all enable UDP data packets to be successfully sent to the UDP server:
1.In -[MyTransparentProxyProvider startProxyWithOptions:completionHandler:], add the exclusion rule "The IP and port of the UDP server, the protocol is UDP";
2.In -[MyTransparentProxyProvider startProxyWithOptions:completionHandler:], add the exclusion rule "All IPs and ports, protocol is UDP";
3.In -[MyTransparentProxyProvider handleNewFlow:] or -[MyTransparentProxyProvider handleNewUDPFlow:initialRemoteEndpoint:], process the UDP Flow and return YES.
Did I do anything wrong?
OK. Then that’s definitely bugworthy. Not only should this work in theory — when you return false from handle-new-flow the system is supposed to deal with the flow as it would if your transparent proxy weren’t installed — but it’s also causing you grief in practice. I encourage you to file a bug about this.
Please post your bug number, just for the record.
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—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"