Move data preparation to the implementation of OpenVPNPacket

2026-04-24 00:00:05 +08:00 · 2018-01-15 17:13:04 +03:00
parent c19bd1df76
commit f840b4a046
3 changed files with 110 additions and 22 deletions
@@ -0,0 +1,95 @@
+//
+//  OpenVPNPacket.m
+//  OpenVPN Adapter
+//
+//  Created by Sergey Abramchuk on 15.01.2018.
+//
+
+#import "OpenVPNPacket.h"
+
+#include <arpa/inet.h>
+
+#include <openvpn/ip/ip.hpp>
+
+@interface OpenVPNPacket () {
+    NSData *_data;
+    NSNumber *_protocolFamily;
+}
+
+@end
+
+@implementation OpenVPNPacket
+
+- (instancetype)initWithVPNData:(NSData *)data {
+    if ((self = [super init])) {
+#if TARGET_OS_IPHONE
+        // Get network protocol family from data prefix
+        NSUInteger prefix_size = sizeof(uint32_t);
+        
+        uint32_t protocol = PF_UNSPEC;
+        [data getBytes:&protocol length:prefix_size];
+        protocol = CFSwapInt32BigToHost(protocol);
+        
+        NSRange range = NSMakeRange(prefix_size, data.length - prefix_size);
+        NSData *packetData = [data subdataWithRange:range];
+#else
+        // Get network protocol family from packet header
+        uint8_t header = 0;
+        [data getBytes:&header length:1];
+        
+        uint32_t protocol = PF_UNSPEC;
+        
+        uint32_t version = openvpn::IPHeader::version(header);
+        switch (version) {
+            case 4:
+                protocol = PF_INET;
+                break;
+            case 6:
+                protocol = PF_INET6;
+                break;
+        }
+
+        NSData *packetData = data;
+#endif
+        
+        _data = packetData;
+        _protocolFamily = @(protocol);
+    }
+    return self;
+}
+
+- (instancetype)initWithPacketFlowData:(NSData *)data protocolFamily:(NSNumber *)protocolFamily {
+    if ((self = [super init])) {
+        _data = data;
+        _protocolFamily = protocolFamily;
+    }
+    return self;
+}
+
+- (NSData *)vpnData {
+#if TARGET_OS_IPHONE
+    // Prepend data with network protocol. It should be done because OpenVPN on iOS uses uint32_t prefixes containing network
+    // protocol.
+    uint32_t prefix = CFSwapInt32HostToBig(_protocolFamily.unsignedIntegerValue);
+    NSUInteger prefix_size = sizeof(uint32_t);
+    
+    NSMutableData *data = [NSMutableData dataWithCapacity:prefix_size + _data.length];
+    
+    [data appendBytes:&prefix length:prefix_size];
+    [data appendData:_data];
+    
+    return data;
+#else
+    return _data;
+#endif
+}
+
+- (NSData *)packetFlowData {
+    return _data;
+}
+
+- (NSNumber *)protocolFamily {
+    return _protocolFamily;
+}
+
+@end