<Network/Network.h>庫是iOS12以后蘋果才公開的，部分接口iOS13才可用。下面的代碼是DTLS連接，基于純PSK建立的。具體的算法集可以根據需要切換。
- DTLSNetworkManager.h文件
//
// DTLSNetworkManager.h
// SSDPDemo
//
// Created by yuchern on 2019/11/15.
// Copyright ? 2019 yuchern. All rights reserved.
//
#import <Foundation/Foundation.h>
#import <Network/Network.h>
NS_ASSUME_NONNULL_BEGIN
#ifdef __IPHONE_13_0
typedef void (^DTLSMessageHandle)(NSData *_Nullable data, NSError *_Nullable error);
typedef void (^DTLSSessionCompletedHandle)(NSError *_Nullable error);
/*
nw_connection_state_invalid = 0,
@const nw_connection_state_waiting The connection is waiting for a usable network before re-attempting
nw_connection_state_waiting = 1,
@const nw_connection_state_preparing The connection is in the process of establishing
nw_connection_state_preparing = 2,
@const nw_connection_state_ready The connection is established and ready to send and receive data upon
nw_connection_state_ready = 3,
@const nw_connection_state_failed The connection has irrecoverably closed or failed
nw_connection_state_failed = 4,
@const nw_connection_state_cancelled The connection has been cancelled by the caller
nw_connection_state_cancelled = 5,
*/
typedef void (^DTLSConnectStateHandle)(nw_connection_state_t state, NSError *_Nullable error);
@interface DTLSNetworkManager : NSObject
/// Config nw_parameters which include pskId, psk, ciphersuite
/// @param pskId pskId
/// @param psk psk
/// @param ciphersuite ciphersuite
- (void)setDTLSParamWithPskId:(NSString *)pskId
psk:(NSString *)psk
ciphersuite:(tls_ciphersuite_t)ciphersuite;
/// Connect to host
/// @param host IP
/// @param port port
/// @param queue queue
/// @param stateHandle callback
- (void)connectDTLSToHost:(NSString *)host
port:(NSString *)port
queue:(dispatch_queue_t)queue
stateHandle:(DTLSConnectStateHandle)stateHandle;
/// Cancel nw_connection and set nil
- (void)closeDTLSConnect;
/// Send message
/// @param message message
/// @param complete complete
- (void)sendDTLSMessage:(NSData *)message
complete:(DTLSSessionCompletedHandle)complete;
/// Receive message
/// @param receiveMessageHandle callback
- (void)receiveDTLSMessage:(DTLSMessageHandle)receiveMessageHandle;
@end
#endif
NS_ASSUME_NONNULL_END
- DTLSNetworkManager.m文件。
代碼中包含了組包，如果你所做的項目數據頭不一樣，需要根據具體修改。
//
// DTLSNetworkManager.m
// SSDPDemo
//
// Created by yuchern on 2019/11/15.
// Copyright ? 2019 yuchern. All rights reserved.
//
#import "DTLSNetworkManager.h"
#ifdef __IPHONE_13_0
NSErrorDomain const DTLSConnectErrorDomain = @"com.home.DTLS.Network.connectHost.error";
NSErrorDomain const DTLSReceiveMessageErrorDomain = @"com..home.DTLS.Network.receiveMessage.error";
NSErrorDomain const DTLSSendMessageErrorDomain = @"com.home.DTLS.Network.sendMessage.error";
@interface DTLSNetworkManager()
@property (nonatomic, strong) nw_parameters_t params;
@property (nonatomic, strong) nw_connection_t connection;
@property (nonatomic, strong) dispatch_queue_t connectQueue;
@property (nonatomic, copy) DTLSMessageHandle receiveMessage;
@property (nonatomic, strong) NSMutableData *readBuf;
@end
@implementation DTLSNetworkManager
#pragma mark - Public
/// Config nw_parameters which include pskId, psk, ciphersuite
/// @param pskId pskId
/// @param psk psk
/// @param ciphersuite ciphersuite
- (void)setDTLSParamWithPskId:(NSString *)pskId
psk:(NSString *)psk
ciphersuite:(tls_ciphersuite_t)ciphersuite API_AVAILABLE(ios(13.0)){
if (pskId == nil || [pskId isEqualToString:@""]) {
return;
}
if (psk == nil || [psk isEqualToString:@""]) {
return;
}
self.params = nw_parameters_create_secure_udp(^(nw_protocol_options_t _Nonnull options) {
sec_protocol_options_t option = nw_tls_copy_sec_protocol_options(options);
dispatch_data_t pskIdData = [self dispatchDataFromNsdata:[pskId dataUsingEncoding:NSUTF8StringEncoding]];
dispatch_data_t pskData = [self dispatchDataFromNsdata:[psk dataUsingEncoding:NSUTF8StringEncoding]];
if (pskIdData == nil || pskData == nil) {
return;
}
sec_protocol_options_add_pre_shared_key(option, pskData, pskIdData);
sec_protocol_options_append_tls_ciphersuite(option, ciphersuite);
sec_protocol_options_set_min_tls_protocol_version(option, tls_protocol_version_DTLSv12);
}, ^(nw_protocol_options_t _Nonnull options) {
NW_PARAMETERS_DEFAULT_CONFIGURATION;
});
}
/// Connect to host
/// @param host IP
/// @param port port
/// @param queue queue
/// @param stateHandle callback
- (void)connectDTLSToHost:(NSString *)host
port:(NSString *)port
queue:(dispatch_queue_t)queue
stateHandle:(DTLSConnectStateHandle)stateHandle API_AVAILABLE(ios(13.0)) {
if (host == nil || [host isEqualToString:@""]) {
return;
}
if (port == nil || [port isEqualToString:@""]) {
return;
}
nw_endpoint_t endpoint = nw_endpoint_create_host([host UTF8String], [port UTF8String]);
self.connection = nw_connection_create(endpoint, self.params);
nw_connection_set_queue(self.connection, queue);
nw_connection_start(self.connection);
nw_connection_set_state_changed_handler(self.connection, ^(nw_connection_state_t state, nw_error_t _Nullable error) {
NSError *nserror;
if (error != nil) {
nserror = [[NSError alloc] initWithDomain:DTLSConnectErrorDomain code:nw_error_get_error_code(error) userInfo:@{@"nw_connection_set_state_changed_handler: nw_error_get_error_domain": @(nw_error_get_error_domain(error))}];
}
if (stateHandle) {
stateHandle(state, nserror);
}
});
[self receiveMsg];
}
/// Cancel nw_connection and set nil
- (void)closeDTLSConnect API_AVAILABLE(ios(13.0)){
nw_connection_cancel(self.connection);
// self.connection = nil;//置nil會報錯
// self.params = nil;
}
/// Send message
/// @param message message
/// @param complete complete
- (void)sendDTLSMessage:(NSData *)message
complete:(DTLSSessionCompletedHandle)complete API_AVAILABLE(ios(13.0)) {
NSData *sendMessage = [self sendMessagePack:message];
dispatch_data_t data = [self dispatchDataFromNsdata:sendMessage];
nw_connection_send(self.connection, data, NW_CONNECTION_FINAL_MESSAGE_CONTEXT, true, ^(nw_error_t _Nullable error) {
NSError *nserror;
if (error != nil) {
nserror = [[NSError alloc] initWithDomain:DTLSSendMessageErrorDomain code:nw_error_get_error_code(error) userInfo:@{@"nw_connection_send: nw_error_get_error_domain": @(nw_error_get_error_domain(error))}];
}
DEVELOPER_LOG_FORMAT(@"DTLS發送數據：%@",sendMessage);
DDLogDebug(@"DTLS發送數據：%@",sendMessage);
if (complete) {
complete(nserror);
}
});
}
- (void)receiveDTLSMessage:(DTLSMessageHandle)receiveMessageHandle {
self.receiveMessage = receiveMessageHandle;
}
#pragma mark - Private
/// Receive message
- (void)receiveMsg API_AVAILABLE(ios(13.0)) {
__weak typeof (self)weakSelf = self;
nw_connection_receive_message(self.connection, ^(dispatch_data_t _Nullable content, nw_content_context_t _Nullable context, bool is_complete, nw_error_t _Nullable error) {
DEVELOPER_LOG_FORMAT(@"DTLS接收數據：content=%@, context=%@, is_complete=%d, error=%@",content, context, is_complete, error);
DDLogDebug(@"DTLS接收數據：content=%@, context=%@, is_complete=%d, error=%@",content, context, is_complete, error);
__strong typeof (weakSelf)strongSelf = weakSelf;
if (error == nil && content != nil) {
NSData *data = [strongSelf nsdataFromDispatchData:content];
if (data != nil) {
[self receiveMessagePack:data];
} else {
NSError *nserror = [[NSError alloc] initWithDomain:DTLSReceiveMessageErrorDomain code:nw_error_get_error_code(error) userInfo:@{@"nw_connection_receive_message: nw_error_get_error_domain": @(nw_error_get_error_domain(error))}];
if (strongSelf.receiveMessage) {
strongSelf.receiveMessage(nil, nserror);
}
}
//nw_connection_receive_message函數只讀取一次消息，讀取完需要再次調用繼續讀取
}else{
NSError *nserror = [[NSError alloc] initWithDomain:DTLSReceiveMessageErrorDomain code:nw_error_get_error_code(error) userInfo:@{@"nw_connection_receive_message: nw_error_get_error_domain": @(nw_error_get_error_domain(error))}];
if (strongSelf.receiveMessage) {
strongSelf.receiveMessage(nil, nserror);
}
}
});
}
/// 發送消息前進行組包，拼接包頭，0xfefe + 包長2字節。4個字節
/// @param data 數據
- (NSData *)sendMessagePack:(NSData *)data {
NSInteger length = data.length;
Byte byte[4] = {0xfe, 0xfe, length >> 8, length & 0x00ff};
NSMutableData *mulData = [[NSMutableData alloc] init];
[mulData appendData:[NSData dataWithBytes:byte length:sizeof(byte)]];
[mulData appendData:data];
return mulData;
}
/// 接收數據的拼包，解決粘包問題
/// @param data 數據
- (void)receiveMessagePack:(NSData *)data API_AVAILABLE(ios(13.0)) {
//將數據存入緩存區
[self.readBuf appendData:data];
//包頭4個字節，2個字節fefe，2個字節包總長度
while (self.readBuf.length > 4) {
//將消息轉化成byte，計算總長度 = 數據的內容長度 + 前面4個字節的頭長度
Byte *bytes = (Byte *)[self.readBuf bytes];
if ((bytes[0]<<8) + bytes[1] == 0xfefe) {
NSUInteger allLength = (bytes[2]<<8) + bytes[3] + 4;
//緩存區的長度大于總長度，證明有完整的數據包在緩存區，然后進行處理
if (self.readBuf.length >= allLength) {
//提取出前面4個字節的頭內容，之所以提取出來，是因為在處理數據問題的時候，比如data轉json的時候，
//頭內容里面包含非法字符，會導致轉化出來的json內容為空，所以要先去掉再處理數據問題
NSMutableData *msgData = [[self.readBuf subdataWithRange:NSMakeRange(0, allLength)] mutableCopy];
[msgData replaceBytesInRange:NSMakeRange(0, 4) withBytes:NULL length:0];
if (self.receiveMessage) {
self.receiveMessage(msgData, nil);
}
//處理完數據后將處理過的數據移出緩存區
self.readBuf = [NSMutableData dataWithData:[self.readBuf subdataWithRange:NSMakeRange(allLength, self.readBuf.length - allLength)]];
}else{
//緩存區內數據包不是完整的，再次從服務器獲取數據，中斷while循環
[self receiveMsg];
break;
}
} else {
//如果包頭不符合要求則丟棄
self.readBuf = nil;
DDLogDebug(@"DTLS拼包數據錯誤:%@",self.readBuf);
break;
}
}
//讀取到服務端數據值后,能再次讀取
[self receiveMsg];
}
#pragma mark - 轉換方法
/// Convert NSData to dispatch_data_t
/// @param nsdata NSData
- (dispatch_data_t)dispatchDataFromNsdata:(NSData *)nsdata API_AVAILABLE(ios(13.0)) {
if (nsdata == nil) {
return nil;
}
Byte byte[nsdata.length];
[nsdata getBytes:byte length:nsdata.length];
dispatch_data_t data = dispatch_data_create(byte, nsdata.length, nil, DISPATCH_DATA_DESTRUCTOR_DEFAULT);
return data;
}
/// Convert dispatch_data_t to NSData
/// @param dispatchData dispatch_data_t
- (NSData *)nsdataFromDispatchData:(dispatch_data_t)dispatchData API_AVAILABLE(ios(13.0)) {
if (dispatchData == nil) {
return nil;
}
const void *buffer = NULL;
size_t size = 0;
dispatch_data_t new_data_file = dispatch_data_create_map(dispatchData, &buffer, &size);
if(new_data_file) {/* to avoid warning really - since dispatch_data_create_map demands we
care about the return arg */}
NSData *nsdata = [[NSData alloc] initWithBytes:buffer length:size];
return nsdata;
}
#pragma mark - 懶加載
- (NSMutableData *)readBuf {
if (_readBuf == nil) {
_readBuf = [[NSMutableData alloc] init];
}
return _readBuf;
}
@end
#endif
