如何从 iOS 下钥匙串中存在的证书中解码序列号、发行者信息等？

Question

我正在创建一个 iOS 应用程序，它可以检索钥匙串中存在的证书（.cer）信息。

参考链接： Link1, Link2

下面是代码：

const char *certLabelString = "Certificates";
    CFStringRef certLabel = CFStringCreateWithCString(
                                                      NULL, certLabelString,
                                                      kCFStringEncodingUTF8);

const void *keys[] =   { kSecClass, kSecAttrLabel, kSecReturnAttributes };
    const void *values[] = { kSecClassCertificate, certLabel, kCFBooleanTrue };

CFDictionaryRef dict = CFDictionaryCreate(NULL, keys,
                                              values, 3,
                                              NULL, NULL)
 if ((SecItemCopyMatching(dict, &myCertData)) == errSecSuccess){
            NSLog(@"Certificate found");

            CFDictionaryRef dictCertificateRef = (CFDictionaryRef)myCertData;

            NSDictionary *dictCertificate = (__bridge NSDictionary *)dictCertificateRef;
            NSLog(@"%@",dictCertificate);

        }

输出：

我获得了证书数据，但我可以看到编码形式的序列号或颁发者名称。

像这样： ISSR = ; P>

谁能告诉我如何解码这些信息？

Answer 1

我也有兴趣知道这一点。到目前为止，浏览证书，我做了以下事情：

id 数据 = [keychainDictionary objectForKey:@"issr"];

然后你可以在这一行设置一个断点，当你越过它时，在调试窗口左侧面板中选择“数据”变量。选择“watch memory of *data”，你会看到一堆垃圾，里面有来自该数据的真实字符串。我不知道如何从那里开始。

获取所有钥匙串项并将其加载到表格视图中的完整方法：

-(void)loadDataSource
{

    //enumerate all items in keychain http://stackoverflow.com/questions/10966969/enumerate-all-keychain-items-in-my-ios-application
    NSMutableDictionary *query = [NSMutableDictionary dictionaryWithObjectsAndKeys:
                                  (__bridge id)kCFBooleanTrue, (__bridge id)kSecReturnAttributes,
                                  (__bridge id)kSecMatchLimitAll, (__bridge id)kSecMatchLimit,
                                  nil];

    NSArray *secItemClasses = [NSArray arrayWithObjects:
                               (__bridge id)kSecClassGenericPassword,
                               (__bridge id)kSecClassInternetPassword,
                               (__bridge id)kSecClassCertificate,
                               (__bridge id)kSecClassKey,
                               (__bridge id)kSecClassIdentity,
                               nil];


    NSMutableArray* results = [NSMutableArray array];

    for(int i = 0; i < (int)secItemClasses.count;i++)
    {
        [results addObject:[NSMutableArray array]];
    }



    for (id secItemClass in secItemClasses) {
        [query setObject:secItemClass forKey:(__bridge id)kSecClass];

        CFTypeRef result = NULL;
        SecItemCopyMatching((__bridge CFDictionaryRef)query, &result);
//        NSLog(@"%@", (__bridge id)result);
        if (result != NULL)
        {
            NSMutableArray* thisSection = results[[secItemClasses indexOfObject:secItemClass]];
            [thisSection addObject:(__bridge id)result];


//            [results addObject:(__bridge id)result];
            CFRelease(result);
        }

        for(NSArray* object in results[[secItemClasses indexOfObject:secItemClass]])
        {
            DLog(@"object is of class: %@",[[object class] description]);

            for (NSDictionary* innerObject in object)
            {
                DLog(@"object is of class: %@",[[innerObject class] description]);


            }




            }

        }

    self.datasource = results;

    [self.tableView reloadData];
}

//这是描述，您可以将其分配给表格视图单元格中的文本标签

-(NSMutableString*)descriptionForObject:(NSDictionary*)object
{
    NSMutableString* string = [[NSMutableString alloc] initWithCapacity:1024];

//    https://developer.apple.com/library/mac/documentation/security/Reference/keychainservices/Reference/reference.html
    //search for kSecAlias for a list of codes

    if(object[@"labl"] != nil)
    {
    [string appendString:[NSString stringWithFormat:@"Label: %@\n",object[@"labl"]]];
    }

    [string appendString:[NSString stringWithFormat:@"Created at: %@\n",object[@"cdat"]]];
    if(object[@"agrp"] != nil)
    {
        [string appendString:[NSString stringWithFormat:@"Belongs to application: %@\n",object[@"agrp"]]];
    }



    for(NSString* key in @[@"issr",@"subj"])
    {
        id data = [object objectForKey:key];


        @try {


            if([data isKindOfClass:[NSData class]]==NO)
            {
                continue;
            }
            NSString* stringAscii = [[NSString alloc] initWithData:data encoding:NSASCIIStringEncoding];


            NSCharacterSet* alphaNumeric = [NSCharacterSet characterSetWithCharactersInString:@"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.@"];


            NSCharacterSet *doNotWant = [alphaNumeric invertedSet];
            NSString* cleanedUpString = [[stringAscii componentsSeparatedByCharactersInSet: doNotWant] componentsJoinedByString: @" "];

            if(cleanedUpString.length>0)
            {
                DLog(@" %@ Cleaned up: %@",key,cleanedUpString);

                [string appendString:[NSString stringWithFormat:@" %@ Cleaned up: %@",key,cleanedUpString]];
            }
        }
        @catch (NSException *exception) {

        }
        @finally {

        }
    }


//    [string appendString:[NSString stringWithFormat:@"Complete description:(%@)\n", [object description]]];



    return string;
}