Question

我正在使用Apple的TCPServer类来打开来自传入连接的套接字。以下是有人在侦听套接字上连接时调用的回调：

static void TCPServerAcceptCallBack(CFSocketRef socket, CFSocketCallBackType type, CFDataRef address, const void *data, void *info) {
TCPServer *server = (TCPServer *)info;
if (kCFSocketAcceptCallBack == type) { 
    // for an AcceptCallBack, the data parameter is a pointer to a CFSocketNativeHandle
    CFSocketNativeHandle nativeSocketHandle = *(CFSocketNativeHandle *)data;
    uint8_t name[SOCK_MAXADDRLEN];
    socklen_t namelen = sizeof(name);
    NSData *peer = nil;
    if (0 == getpeername(nativeSocketHandle, (struct sockaddr *)name, &namelen)) {
        peer = [NSData dataWithBytes:name length:namelen];
    }

    CFReadStreamRef readStream = NULL;
    CFWriteStreamRef writeStream = NULL;
    CFStreamCreatePairWithSocket(kCFAllocatorDefault, nativeSocketHandle, &readStream, &writeStream);
    if (readStream && writeStream) {
        CFReadStreamSetProperty(readStream, kCFStreamPropertyShouldCloseNativeSocket, kCFBooleanTrue);
        CFWriteStreamSetProperty(writeStream, kCFStreamPropertyShouldCloseNativeSocket, kCFBooleanTrue);
        [server handleNewConnectionFromAddress:peer inputStream:(NSInputStream *)readStream outputStream:(NSOutputStream *)writeStream];
    } else {
        // on any failure, need to destroy the CFSocketNativeHandle 
        // since we are not going to use it any more
        close(nativeSocketHandle);
    }
    if (readStream) CFRelease(readStream);
    if (writeStream) CFRelease(writeStream);
}
}

有没有办法获取正在连接的设备的主机名？问候，佐

[编辑] 我试过这样的东西来提取ip：

struct sockaddr_in *s = (struct sockaddr_in*)name;
char *ipstr = malloc(INET_ADDRSTRLEN);         
ipstr = inet_ntoa(s->sin_addr);

NSLog(@"ip = %s", ipstr);

但它给了我0.0.0.0。

[编辑] 仍在努力，仍然没有成功。根据apple的doc，地址参数是：

保存结构sockaddr内容的CFData对象，适用于s的协议族（例如struct sockaddr_in或struct sockaddr_in6），标识s所连接的远程地址。除了kCFSocketAcceptCallBack和kCFSocketDataCallBack回调之外，此值为NULL。

但是我无法提取除132.20.0.1之外的任何其他IP（这显然不是我期望的IP）我真的很困惑，如果有人可以帮助我的话会很棒！

Answer 1

在尝试按照您的方式获取地址后，我想出了一个适合我的代码的轻微变体。如果您正在处理IPv6地址，则此代码正常工作，但很容易更改为使用IPv4。无论如何，我将不得不更改代码。

- (void)getPublicClientAddress {
    // Get public IP from stream

    // Get hands on appropriate data structures via the socket number
    CFSocketNativeHandle nativeSocketHandle = _socketnumber;
    uint8_t name[SOCK_MAXADDRLEN];
    socklen_t namelen = sizeof(name);
    NSData *peer = nil;
    if (0 == getpeername(nativeSocketHandle, (struct sockaddr *)name, &namelen)) {
        peer = [NSData dataWithBytes:name length:namelen];
    }

    // TODO distiguish between ipv4 and ipv6
    struct sockaddr_in6 *s = (struct sockaddr_in6*)name;

    // convert ip to string
    char *ipstr = malloc(INET6_ADDRSTRLEN);
    struct in6_addr *ipv6addr = &s->sin6_addr;  // used pointer here, but that really should make no difference
    inet_ntop(AF_INET6, ipv6addr, ipstr, sizeof(ipstr)); // used a different function here

    // convert port to int
    int portnumber = s->sin6_port;

    // Save in properties
    _publicIP   = [NSString stringWithFormat:@"%s", ipstr];
    _publicPort = [NSString stringWithFormat:@"%d", portnumber];
}

所以这段代码对我有用，我希望它可以帮助那些在搜索答案时偶然发现这篇文章的人。

获取连接到套接字的主机的主机名

1 个答案: