我有同样的问题。与 一起使用，但不能与 Java 代码中的任何组合一起使用。kSecPaddingNonekSecPaddingPKCS1PKCS1

但是，在没有填充的情况下使用它不是一个好主意。

因此，在iOS上，替换并在Java代码中使用。这对我确实有效。kSecPaddingNonekSecPaddingOAEPRSA/NONE/OAEPWithSHA1AndMGF1Padding

解决方案RSA/None/NoPadding

好吧，所以我让它工作，但没有填充。这部分真的让我感到沮丧，我把它留给其他人来尝试帮助。也许我最终会在github上发布我作为库的东西，一个用于Obj-C，一个用于Java。以下是我迄今为止的发现。

TL;DR：使用最少的属性将密钥保存到钥匙串中，以使检索更简单。使用 进行加密，但使用 。使用BouncyCastle和算法在Java端解密。SecKeyEncryptkSecPaddingNoneRSA/None/NoPadding

将 RSA 公钥从 Java 发送到 iOS

使用 X.509 证书

我想验证直接发送公钥，剥离ASN.1标头并保存是否确实在做它应该做的事情。因此，我考虑将公钥作为证书发送过来。我想感谢David Benko提供了一个加密库（https://github.com/DavidBenko/DBTransitEncryption），帮助我进行了证书转换。我实际上并没有使用他的图书馆，因为1。我已经在使用/用于我的AES加密和2。他没有Java端组件，所以我需要在那里编写自己的AES解密，我不想这样做。对于那些有兴趣并希望采用这种方法的人，以下是我的代码，用于在Java端创建证书，然后将该证书转换为iOS上的公钥：RNCryptorJNCryptor

* 重要提示：请替换为真实的日志记录语句。我只用它来测试，而不是在生产中。e.printStackTrace()

爪哇：

public static X509Certificate generateCertificate (KeyPair newKeys) {
    Security.addProvider(new BouncyCastleProvider());
    Date startDate = new Date();
    Date expiryDate = new DateTime().plusYears(100).toDate();

    BigInteger serialNumber = new BigInteger(10, new Random());
    try {
        ContentSigner sigGen = new JcaContentSignerBuilder("SHA1withRSA").setProvider("BC").build(newKeys
                                                                                                          .getPrivate());
        SubjectPublicKeyInfo subjectPublicKeyInfo = new SubjectPublicKeyInfo(ASN1Sequence.getInstance(newKeys
                                                                                                              .getPublic().getEncoded()
                                                                                                              ));
        X500Name dnName = new X500Name("CN=FoodJudge API Certificate");
        X509v1CertificateBuilder builder = new X509v1CertificateBuilder(dnName,
                                                                        serialNumber,
                                                                        startDate, expiryDate,
                                                                        dnName,
                                                                        subjectPublicKeyInfo);
        X509CertificateHolder holder = builder.build(sigGen);
        return new JcaX509CertificateConverter().setProvider("BC").getCertificate(holder);
    }
    catch (OperatorCreationException e) {
        e.printStackTrace();
    }
    catch (CertificateException e) {
        e.printStackTrace();
    }
    return null;
}

Obj-C：

- (SecKeyRef)extractPublicKeyFromCertificate:(NSData *)certificateBytes {
    if (certificateBytes == nil) {
        return nil;
    }

    SecCertificateRef certificate = SecCertificateCreateWithData(kCFAllocatorDefault, ( __bridge CFDataRef) certificateBytes);
    if (certificate == nil) {
        NSLog(@"Can not read certificate from data");
        return false;
    }

    SecTrustRef trust;
    SecPolicyRef policy = SecPolicyCreateBasicX509();
    OSStatus returnCode = SecTrustCreateWithCertificates(certificate, policy, &trust);

    // release the certificate as we're done using it
    CFRelease(certificate);
    // release the policy
    CFRelease(policy);

    if (returnCode != errSecSuccess) {
        NSLog(@"SecTrustCreateWithCertificates fail. Error Code: %d", (int)returnCode);
        return nil;
    }

    SecTrustResultType trustResultType;
    returnCode = SecTrustEvaluate(trust, &trustResultType);
    if (returnCode != errSecSuccess) {
        // TODO log
        CFRelease(trust);
        return nil;
    }

    SecKeyRef publicKey = SecTrustCopyPublicKey(trust);
    CFRelease(trust);

    if (publicKey == nil) {
        NSLog(@"SecTrustCopyPublicKey fail");
        return nil;
    }

    return publicKey;
}

使用 RSA 公钥

请务必注意，您不需要将公钥作为证书发送。实际上，在发现公钥保存不正确（见下文）后，我还原了此代码并将公钥保存到我的设备中。您需要按照其中一篇博客文章中提到的条带去标题。该代码在此处重新发布（为清楚起见，已格式化）。ASN.1

+ (NSData *)stripPublicKeyHeader:(NSData *)keyBits {
    // Skip ASN.1 public key header
    if (keyBits == nil) {
        return nil;
    }

    unsigned int len = [keyBits length];
    if (!len) {
        return nil;
    }

    unsigned char *c_key = (unsigned char *)[keyBits bytes];
    unsigned int  idx    = 0;

    if (c_key[idx++] != 0x30) {
        return nil;
    }

    if (c_key[idx] > 0x80) {
        idx += c_key[idx] - 0x80 + 1;
    }
    else {
        idx++;
    }

    if (idx >= len) {
        return nil;
    }

    if (c_key[idx] != 0x30) {
        return nil;
    }

    idx += 15;

    if (idx >= len - 2) {
        return nil;
    }

    if (c_key[idx++] != 0x03) {
        return nil;
    }

    if (c_key[idx] > 0x80) {
        idx += c_key[idx] - 0x80 + 1;
    }
    else {
        idx++;
    }

    if (idx >= len) {
        return nil;
    }

    if (c_key[idx++] != 0x00) {
        return nil;
    }

    if (idx >= len) {
        return nil;
    }

    // Now make a new NSData from this buffer
    return([NSData dataWithBytes:&c_key[idx] length:len - idx]);
}

所以我会像这样简单地保存密钥：

- (void)storeServerPublicKey:(NSString *)serverPublicKey {
    if (!serverPublicKey) {
        return;
    }
    SecKeyWrapper *secKeyWrapper = [SecKeyWrapper sharedWrapper];
    NSData *decryptedServerPublicKey = [[NSData alloc] initWithBase64EncodedString:serverPublicKey options:0];

    NSData *strippedServerPublicKey = [SecKeyWrapper stripPublicKeyHeader:decryptedServerPublicKey];
    if (!strippedServerPublicKey) {
        return;
    }
    [secKeyWrapper savePublicKeyToKeychain:strippedServerPublicKey tag:@"com.sampleapp.publickey"];
}

将 RSA 公钥保存到钥匙串

这太疯狂了。事实证明，即使我保存了钥匙串的钥匙，我检索到的也不是我放入的！当我将保存的 base64 密钥与用于加密 AES 密钥的 base64 密钥进行比较时，我偶然发现了这一点。因此，我发现最好简化保存密钥时使用的NSDictionary。以下是我最终得到的结果：

- (void)savePublicKeyToKeychain:(NSData *)key tag:(NSString *)tagString {
    NSData *tag = [self getKeyTag:tagString];

    NSDictionary *saveDict = @{
            (__bridge id) kSecClass : (__bridge id) kSecClassKey,
            (__bridge id) kSecAttrKeyType : (__bridge id) kSecAttrKeyTypeRSA,
            (__bridge id) kSecAttrApplicationTag : tag,
            (__bridge id) kSecAttrKeyClass : (__bridge id) kSecAttrKeyClassPublic,
            (__bridge id) kSecValueData : key
    };
    [self saveKeyToKeychain:saveDict tag:tagString];
}

- (void)saveKeyToKeychain:(NSDictionary *)saveDict tag:(NSString *)tagString {
    OSStatus sanityCheck = SecItemAdd((__bridge CFDictionaryRef) saveDict, NULL);
    if (sanityCheck != errSecSuccess) {
        if (sanityCheck == errSecDuplicateItem) {
            // delete the duplicate and save again
            sanityCheck = SecItemDelete((__bridge CFDictionaryRef) saveDict);
            sanityCheck = SecItemAdd((__bridge CFDictionaryRef) saveDict, NULL);
        }
        if (sanityCheck != errSecSuccess) {
            NSLog(@"Problem saving the key to keychain, OSStatus == %d.", (int) sanityCheck);
        }
    }
    // remove from cache
    [keyCache removeObjectForKey:tagString];
}

要检索我的密钥，我使用以下方法：

 - (SecKeyRef)getKeyRef:(NSString *)tagString isPrivate:(BOOL)isPrivate {
     NSData *tag = [self getKeyTag:tagString];

     id keyClass = (__bridge id) kSecAttrKeyClassPublic;
     if (isPrivate) {
         keyClass = (__bridge id) kSecAttrKeyClassPrivate;
     }

     NSDictionary *queryDict = @{
             (__bridge id) kSecClass : (__bridge id) kSecClassKey,
             (__bridge id) kSecAttrKeyType : (__bridge id) kSecAttrKeyTypeRSA,
             (__bridge id) kSecAttrApplicationTag : tag,
             (__bridge id) kSecAttrKeyClass : keyClass,
             (__bridge id) kSecReturnRef : (__bridge id) kCFBooleanTrue
     };
     return [self getKeyRef:queryDict tag:tagString];
 }

- (SecKeyRef)getKeyRef:(NSDictionary *)query tag:(NSString *)tagString {
    SecKeyRef keyReference = NULL;
    OSStatus sanityCheck = SecItemCopyMatching((__bridge CFDictionaryRef) query, (CFTypeRef *) &keyReference);
    if (sanityCheck != errSecSuccess) {
        NSLog(@"Error trying to retrieve key from keychain. tag: %@. sanityCheck: %li", tagString, sanityCheck);
        return nil;
    }
    return keyReference;
}

在一天结束时，我只能让它工作而不填充。我不确定为什么不能删除填充，所以如果有人有任何见解，请告诉我。BouncyCastle

这是我的加密代码（从David Benko修改）：

- (NSData *)encryptData:(NSData *)content usingPublicKey:(NSString *)publicKeyTag {
    SecKeyRef publicKey = [self getKeyRef:publicKeyTag isPrivate:NO];
    NSData *keyBits = [self getKeyBitsFromKey:publicKey];
    NSString *keyString = [keyBits base64EncodedStringWithOptions:0];
    NSAssert(publicKey != nil,@"Public key can not be nil");

    size_t cipherLen = SecKeyGetBlockSize(publicKey); // convert to byte
    void *cipher = malloc(cipherLen);
    size_t maxPlainLen = cipherLen - 12;

    size_t plainLen = [content length];
    if (plainLen > maxPlainLen) {
        NSLog(@"content(%ld) is too long, must < %ld", plainLen, maxPlainLen);
        return nil;
    }

    void *plain = malloc(plainLen);
    [content getBytes:plain
               length:plainLen];

    OSStatus returnCode = SecKeyEncrypt(publicKey, kSecPaddingNone, plain,
            plainLen, cipher, &cipherLen);

    NSData *result = nil;
    if (returnCode != errSecSuccess) {
        NSLog(@"SecKeyEncrypt fail. Error Code: %d", (int)returnCode);
    }
    else {
        result = [NSData dataWithBytes:cipher
                                length:cipherLen];
    }

    free(plain);
    free(cipher);

    return result;
}

以下是我在Java端解密的方式：

private Response authenticate (String encryptedSymmetricString) {
    byte[] encryptedSymmetricKey = Base64.decodeBase64(encryptedSymmetricKeyString);
    String privateKey = Server.getServerPrivateKey();
    byte[] decryptedSymmetricKey = KeyHandler.decryptMessage(encryptedSymmetricKey, privateKey,
                                                             KeyHandler.ASYMMETRIC_CIPHER_ALGORITHM);
}

public static byte[] decryptMessage (byte[] message, String privateKeyString, String algorithm) {
    if (message == null || privateKeyString == null) {
        return null;
    }
    PrivateKey privateKey = getPrivateKey(privateKeyString);
    return decryptMessage(message, privateKey, algorithm);
}

public static byte[] decryptMessage (byte[] message, PrivateKey privateKey, String algorithm) {
    if (message == null || privateKey == null) {
        return null;
    }
    Cipher cipher = createCipher(Cipher.DECRYPT_MODE, privateKey, algorithm, true);
    if (cipher == null) {
        return null;
    }

    try {
        return cipher.doFinal(message);
    }
    catch (IllegalBlockSizeException e) {
        e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
        return null;
    }
    catch (BadPaddingException e) {
        e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
        return null;
    }
}