以编程方式在 OS X 钥匙串中存储对称密钥

Posted 2023-02-23

【中文标题】以编程方式在 OS X 钥匙串中存储对称密钥

【英文标题】：Storing a symmetric key in OS X keychain programmatically

【发布时间】：2014-02-27 09:56:50

【问题描述】：

我有一个对称密钥，我想将它存储在 OS X 钥匙串中。 存储密码和用户名工作正常，所以我改变了我的代码 存储我想稍后由我的应用程序使用的对称密钥。 我使用以下代码作为响应：

指定的属性不存在。

这是我的代码：

// Identifier for symmetric key
static const uint8_t keyIdentfier[] = "net.eurobertics.TestKey";
NSData *tag = [[NSData alloc] initWithBytes:keyIdentfier length:sizeof(keyIdentfier)];

// Simple keygen algo - JUST FOR EXAMPLE DO NOT USE!
NSMutableData *key = [NSMutableData dataWithLength:8];
SecRandomCopyBytes(kSecRandomDefault, 8, key.mutableBytes);
NSString *base64key = [key base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];

// Dictionary for keychain - insert a symmetric key with following attributes
NSMutableDictionary *dict = [[NSMutableDictionary alloc] init];
[dict setObject:(id)kSecClassKey forKey:(id)kSecClass];
[dict setObject:tag forKey:(id)kSecAttrApplicationTag];
[dict setObject:[NSNumber numberWithUnsignedInteger:CSSM_ALGID_AES] forKey:(id)kSecAttrKeyType];
[dict setObject:[NSNumber numberWithUnsignedInteger:(unsigned int)(kCCKeySizeAES128 << 3)] forKey:(id)kSecAttrKeySizeInBits];
[dict setObject:[NSNumber numberWithUnsignedInteger:(unsigned int)(kCCKeySizeAES128 << 3)] forKey:(id)kSecAttrEffectiveKeySize];
[dict setObject:(id)kCFBooleanTrue forKey:(id)kSecAttrCanEncrypt];
[dict setObject:(id)kCFBooleanTrue forKey:(id)kSecAttrCanDecrypt];
[dict setObject:(id)kCFBooleanFalse forKey:(id)kSecAttrCanSign];
[dict setObject:(id)kCFBooleanFalse forKey:(id)kSecAttrCanVerify];
[dict setObject:(id)kCFBooleanFalse forKey:(id)kSecAttrCanWrap];
[dict setObject:(id)kCFBooleanFalse forKey:(id)kSecAttrCanUnwrap];
[dict setObject:(id)kCFBooleanFalse forKey:(id)kSecAttrCanDerive];
[dict setObject:key forKey:(id)kSecValueData];

// Insert key into keychain based on dictionary attributes above
OSStatus osstatus = SecItemAdd((__bridge CFDictionaryRef)dict, NULL);

// Set responsefield
[[self responseField] setStringValue:[NSString stringWithFormat:@"Key: %@\n\nStatus: %@", base64key, SecCopyErrorMessageString(osstatus, NULL)]];

我知道 SecItemAdd 主要用于 ios，但我想稍后将我的应用程序移植到 iOS，所以 我想要更兼容。将密钥存储在默认（通常是登录）钥匙串中 对我来说绝对没问题，因为我会定期通过我的应用程序使用密钥。

【参考方案1】：

我通过我的另一个问题发现了为什么这不起作用：

Storing a symmetric key in OS X keychain programmatically

希望对某人有所帮助