objective-c - 如何为 SSL 握手配置 CFStream（或 NSStream）？

Question

我正在使用 CFStream/NSStream 进行 http 连接。我希望能够检测到 SSL 握手在三种情况下失败：

• 案例A：服务器不受信任
• 案例 B：服务器受信任但要求客户端证书
• 案例 C：服务器不受信任，它要求客户端证书

今天没有对我的 CFStream 的 SSL 属性做任何事情，我得到：

• 案例A：错误-9807
• 案例B：没有错误但服务器拒绝连接（错误500）
• 案例 C：错误 9807

有没有办法配置 CFStream 以正确区分这三种情况？或者在 SSL 握手期间有一些回调？

谢谢你的帮助。

Answer 1

前段时间，我使用 SSL 与 CFSockets 进行了相同的操作。CFStream 处理所有握手的东西。我为 NSStream 写了一个小类添加（基本代码来自 Apple，不再有链接，如果找到我会添加它）。这对我有用。

界面

@interface NSStream (FSNetworkAdditions)

+ (void)qNetworkAdditions_getStreamsToHostNamed:(NSString *)hostName
                                           port:(NSInteger)port
                                    inputStream:(out NSInputStream **)inputStreamPtr
                                   outputStream:(out NSOutputStream **)outputStreamPtr;

@end

和实施

#import "FSNetworkAdditions.h"

@implementation NSStream (FSNetworkAdditions)

+ (void)qNetworkAdditions_getStreamsToHostNamed:(NSString *)hostName
                                           port:(NSInteger)port
                                    inputStream:(out NSInputStream **)inputStreamPtr
                                   outputStream:(out NSOutputStream **)outputStreamPtr
{
    CFReadStreamRef     readStream;
    CFWriteStreamRef    writeStream;

    assert(hostName != nil);
    assert( (port > 0) && (port < 65536) );
    assert( (inputStreamPtr != NULL) || (outputStreamPtr != NULL) );

    readStream = NULL;
    writeStream = NULL;

    CFStreamCreatePairWithSocketToHost(
                                       NULL,
                                       (CFStringRef) hostName,
                                       port,
                                       ((inputStreamPtr  != NULL) ? &readStream : NULL),
                                       ((outputStreamPtr != NULL) ? &writeStream : NULL)
                                       );

    NSDictionary *settings = [[NSDictionary alloc] initWithObjectsAndKeys:
                              [NSNumber numberWithBool:YES], kCFStreamSSLAllowsExpiredCertificates,
                              [NSNumber numberWithBool:YES], kCFStreamSSLAllowsAnyRoot,
                              [NSNumber numberWithBool:YES], kCFStreamSSLAllowsExpiredRoots,
                              [NSNumber numberWithBool:NO], kCFStreamSSLValidatesCertificateChain,
                              //kCFNull,kCFStreamSSLPeerName,
                              kCFStreamSocketSecurityLevelSSLv3, kCFStreamSSLLevel,
                              [NSNumber numberWithBool:YES], kCFStreamPropertyShouldCloseNativeSocket,
                              nil];

    if (readStream) {
        CFReadStreamSetProperty(readStream, kCFStreamPropertySSLSettings, (CFTypeRef)settings);
    }

    if (writeStream) {
        CFWriteStreamSetProperty(writeStream, kCFStreamPropertySSLSettings, (CFTypeRef)settings);
    }

    if (inputStreamPtr != NULL) {
        *inputStreamPtr  = CFBridgingRelease(readStream);
    }
    if (outputStreamPtr != NULL) {
        *outputStreamPtr = CFBridgingRelease(writeStream);
    }


}

@end

就是这样，您现在可以像这样连接到服务器：

NSInputStream   *inputStream;
NSOutputStream  *outputStream;
[NSStream qNetworkAdditions_getStreamsToHostNamed:host 
                                             port:port 
                                      inputStream:&inputStream 
                                     outputStream:&outputStream];

        inputStream.delegate  = self;
        outputStream.delegate = self;

其中“self”符合 NSStreamDelegate 协议。

我希望这些片段有帮助。