keychain使用说明书

//通过Dictionary去查询、修改、新增
- (NSMutableDictionary *)newSearchDictionary:(NSString *)identifier {
    NSMutableDictionary *searchDictionary = [[NSMutableDictionary alloc] init];
    //指定item的类型为GenericPassword
    [searchDictionary setObject:(id)kSecClassGenericPassword forKey:(id)kSecClass];
    
    //类型为GenericPassword的信息必须提供以下两条属性作为unique identifier
    [searchDictionary setObject:encodedIdentifier forKey:(id)kSecAttrAccount]；
    [searchDictionary setObject:encodedIdentifier forKey:(id)kSecAttrService]；
    
    return searchDictionary;
}

//查询
- (NSData *)searchKeychainCopyMatching:(NSString *)identifier {
    NSMutableDictionary *searchDictionary = [self newSearchDictionary:identifier];
    
    //在搜索keychain item的时候必须提供下面的两条用于搜索的属性
    //只返回搜索到的第一条item
    [searchDictionary setObject:(id)kSecMatchLimitOne forKey:(id)kSecMatchLimit];
    //返回item的kSecValueData
    [searchDictionary setObject:(id)kCFBooleanTrue forKey:(id)kSecReturnData];
    
    NSData *result = nil;
    OSStatus status = SecItemCopyMatching((CFDictionaryRef)searchDictionary,
                                          (CFTypeRef *)&result);
    [searchDictionary release];
    return result;
}

//新增


//修改

iOS的Keychain由系统管理并且进行加密，Keychain内的信息会随着iPhone的数据一起备份。但是kSecAttrAccessible 属性被设置为后缀是ThisDeviceOnly的数据会被以硬件相关的密钥(key)加密。并且不会随着备份移动至其他设备。

kSecAttrAccessible变量用来指定这条信息的保护程度。我们需要对这个选项特别注意，并且使用最严格的选项。这个键（key）可以设置6种值。

CFTypeRef kSecAttrAccessible;//可访问性类型透明
kSecAttrAccessibleWhenUnlocked;//解锁可访问，备份
kSecAttrAccessibleAfterFirstUnlock;//第一次解锁后可访问，备份
kSecAttrAccessibleAlways;//一直可访问，备份
kSecAttrAccessibleWhenUnlockedThisDeviceOnly;//解锁可访问，不备份
kSecAttrAccessibleAfterFirstUnlockThisDeviceOnly;//第一次解锁后可访问，不备份
kSecAttrAccessibleAlwaysThisDeviceOnly;//一直可访问，不备份

Keychain从iOS7.0开始也支持iCloud备份。把kSecAttrSynchronizable属性设置为@YES，这样后Keychain就能被iCloud备份并且跨设备分享。

不过在添加kSecAttrSynchronizable属性后，这条属性会被作为每条Keychain Item的主要的Key之一，所以在搜索，更新，删除的时候如果查询字典内没有这一条属性，item就匹配不到。

- (NSString *)getUUID
{
    NSString * strUUID = [self searchKeychainCopyMatching:kUUIDKeychainIdentify];

    //首次执行该方法时，uuid为空
    if ([strUUID isEqualToString:@""] || !strUUID)
    {
        //生成一个uuid的方法
        CFUUIDRef uuidRef = CFUUIDCreate(kCFAllocatorDefault);
        
        strUUID = (NSString *)CFBridgingRelease(CFUUIDCreateString (kCFAllocatorDefault,uuidRef));
        
        //将该uuid保存到keychain
        NSMutableDictionary *dict = [self newSearchDictionary:kUUIDKeychainIdentify];
        NSData *Data = [strUUID dataUsingEncoding:NSUTF8StringEncoding];
        //这里要做一次加密，测试用就没有写
        [dict setObject:Data forKey:(id)kSecValueData];
        SecItemAdd((CFDictionaryRef)dict, NULL);
        
    }
    return strUUID;
}

//bundleSeedID 也就是我们需要的Team ID

- (NSString *)bundleSeedID {
    NSDictionary *query = [NSDictionary dictionaryWithObjectsAndKeys:
                           kSecClassGenericPassword, kSecClass,
                           @"bundleSeedID", kSecAttrAccount,
                           @"", kSecAttrService,
                           (id)kCFBooleanTrue, kSecReturnAttributes,
                           nil];
    CFDictionaryRef result = nil;
    OSStatus status = SecItemCopyMatching((CFDictionaryRef)query, (CFTypeRef *)&result);
    if (status == errSecItemNotFound)
        status = SecItemAdd((CFDictionaryRef)query, (CFTypeRef *)&result);
    if (status != errSecSuccess)
        return nil;
    NSString *accessGroup = [(__bridge NSDictionary *)result objectForKey:kSecAttrAccessGroup];
    NSArray *components = [accessGroup componentsSeparatedByString:@"."];
    NSString *bundleSeedID = [[components objectEnumerator] nextObject];
    CFRelease(result);
    return bundleSeedID;
}

 [self haveBundleIdentifier];//获取BundleIdentifier
    [self haveappidentifierprefix];//获取appidentifierprefix
   [self haveBundleExecutable];//获取项目名称
- (void)haveBundleExecutable{


- (void)haveappidentifierprefix{
    NSString * prefix = [self bundleSeedID];
    NSLog(@"prefix-->%@",prefix);
    
}

- (NSString *)bundleSeedID {
    NSDictionary *query = [NSDictionary dictionaryWithObjectsAndKeys:
                           kSecClassGenericPassword, kSecClass,
                           @"bundleSeedID", kSecAttrAccount,
                           @"", kSecAttrService,
                           (id)kCFBooleanTrue, kSecReturnAttributes,
                           nil];
    CFDictionaryRef result = nil;
    OSStatus status = SecItemCopyMatching((CFDictionaryRef)query, (CFTypeRef *)&result);
    if (status == errSecItemNotFound)
        status = SecItemAdd((CFDictionaryRef)query, (CFTypeRef *)&result);
    if (status != errSecSuccess)
        return nil;
    NSString *accessGroup = [(__bridge NSDictionary *)result objectForKey:kSecAttrAccessGroup];
    NSArray *components = [accessGroup componentsSeparatedByString:@"."];
    NSString *bundleSeedID = [[components objectEnumerator] nextObject];
    CFRelease(result);
    return bundleSeedID;
}


- (void)haveBundleIdentifier{
    NSString * identifier = [[NSBundle mainBundle]bundleIdentifier];
    NSLog(@"identifier--->%@",identifier);
}

- (void)haveBundleExecutable{

    NSString *executableFile = [[[NSBundle mainBundle] infoDictionary] objectForKey:(NSString *)kCFBundleExecutableKey];    //获取项目名称
    NSLog(@"executableFile-->%@",executableFile);
    
    NSString *version = [[[NSBundle mainBundle] infoDictionary] objectForKey:(NSString *)kCFBundleVersionKey];      //获取项目版本号
    
    
    
    NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];
    NSLog(@"infoDictionary-->%@",infoDictionary);
    // app名称
    NSString *app_Name = [infoDictionary objectForKey:@"CFBundleDisplayName"];
    // app版本
    NSString *app_Version = [infoDictionary objectForKey:@"CFBundleShortVersionString"];
    // app build版本
    NSString *app_build = [infoDictionary objectForKey:@"CFBundleVersion"];
}