我想将 [密钥对] 分开并单独使用它们来加密/解密

I want to split [the keypair] apart and use them individually to encrypt/decrypt

...关于如何分离密钥的任何想法，然后可能将它们重新放在密钥对"中，或者如何单独使用它们来加密/解密某些字符串变量?

... Any ideas on how to separate the keys, then maybe put them back together in a "keypair" or maybe how to use them separately to encrypt/decrypt some string variables?

您可以使用 RSAPublicKey_dup 和 RSAPrivateKey_dup，而无需通过 ASN.1/DER 或 PEM 编码对它们进行往返.在这里，往返包括使用PEM_write_bio_RSAPublicKey 和PEM_read_bio_RSAPublicKey 之类的函数.

You can use RSAPublicKey_dup and RSAPrivateKey_dup, without the need to round trip them by ASN.1/DER or PEM encoding them. Here, round tripping consist of using a functions like PEM_write_bio_RSAPublicKey and PEM_read_bio_RSAPublicKey.

下面是使用它们的示例程序.它是用 C++ 编写的(感谢您添加该标签).

Below is a sample program that uses them. Its written in C++ (thanks for adding that tag).

虽然您可以将它们分开，但它们都使用 RSA 结构.公钥有一些成员设置为 NULL，比如私有指数.

While you can separate them, they both use the RSA structure. The public key has some members set to NULL, like the private exponent.

您还可以使用 RSA_print、RSA_print_fp 和朋友打印密钥.请参阅下面的 RSA_print (3) 或其用法.

You can also print the keys with RSA_print, RSA_print_fp and friends. See RSA_print (3) or its use below.

// g++ -Wall -Wextra -std=c++11 -stdlib=libc++ -I/usr/local/ssl/macosx-x64/include 
//     t.cpp -o t.exe /usr/local/ssl/macosx-x64/lib/libcrypto.a

#include <memory>
using std::unique_ptr;

#include <openssl/bn.h>
#include <openssl/rsa.h>

#include <cassert>
#define ASSERT assert

using BN_ptr = std::unique_ptr<BIGNUM, decltype(&::BN_free)>;
using RSA_ptr = std::unique_ptr<RSA, decltype(&::RSA_free)>;

int main(int argc, char* argv[])
{
    int rc;

    RSA_ptr rsa(RSA_new(), ::RSA_free);
    BN_ptr bn(BN_new(), ::BN_free);

    rc = BN_set_word(bn.get(), RSA_F4);
    ASSERT(rc == 1);

    rc = RSA_generate_key_ex(rsa.get(), 2048, bn.get(), NULL);
    ASSERT(rc == 1);

    RSA_ptr rsa_pub(RSAPublicKey_dup(rsa.get()), ::RSA_free);
    RSA_ptr rsa_priv(RSAPrivateKey_dup(rsa.get()), ::RSA_free);

    fprintf(stdout, "
");
    RSA_print_fp(stdout, rsa_pub.get(), 0);

    fprintf(stdout, "
");
    RSA_print_fp(stdout, rsa_priv.get(), 0);

    return 0;
}

这是输出:

$ ./t.exe 

Public-Key: (2048 bit)
Modulus:
    00:aa:5a:cc:30:52:f1:e9:49:3d:a6:25:00:33:29:
    a6:fa:f7:53:e0:3c:73:4c:91:41:66:20:ec:62:1f:
    27:2a:2a:6c:0f:90:f8:d9:7e:d5:ec:72:7b:38:8c:
    ca:12:60:f8:d1:fb:f2:65:7c:b1:3a:b6:4e:26:ba:
    5b:86:cc:30:f2:fc:be:c3:a2:00:b9:ea:81:fa:1c:
    22:4e:f7:be:a1:1a:66:90:13:b6:12:66:26:23:6d:
    22:15:7d:3b:a4:99:44:38:fa:1c:70:63:4e:50:6f:
    66:38:6c:f6:1a:13:e1:c7:dc:a6:a1:eb:6f:f9:c9:
    59:c8:30:dc:c2:1b:dc:6c:9d:ea:0c:3d:52:5a:00:
    ea:c9:c9:85:51:21:9f:ec:95:b3:dc:c2:50:21:29:
    c2:64:6c:1e:34:36:d8:61:59:ab:3c:a2:cc:e8:ef:
    57:c3:7f:49:86:be:e3:42:88:1b:39:10:b8:2f:fa:
    81:ef:a0:94:99:0c:71:ae:1e:82:7f:e3:6e:00:6e:
    02:13:66:bb:a9:31:58:ec:90:39:9c:bc:9c:8c:90:
    e9:20:f7:20:8e:d6:a3:a3:df:a2:4a:0f:0f:39:b5:
    57:b9:ef:6a:27:e0:1a:ed:f6:ce:0d:87:cd:43:03:
    bf:67:ef:ff:fd:da:98:cc:22:ab:5e:8d:7b:43:d3:
    90:4d
Exponent: 65537 (0x10001)

Private-Key: (2048 bit)
modulus:
    00:aa:5a:cc:30:52:f1:e9:49:3d:a6:25:00:33:29:
    a6:fa:f7:53:e0:3c:73:4c:91:41:66:20:ec:62:1f:
    27:2a:2a:6c:0f:90:f8:d9:7e:d5:ec:72:7b:38:8c:
    ca:12:60:f8:d1:fb:f2:65:7c:b1:3a:b6:4e:26:ba:
    5b:86:cc:30:f2:fc:be:c3:a2:00:b9:ea:81:fa:1c:
    22:4e:f7:be:a1:1a:66:90:13:b6:12:66:26:23:6d:
    22:15:7d:3b:a4:99:44:38:fa:1c:70:63:4e:50:6f:
    66:38:6c:f6:1a:13:e1:c7:dc:a6:a1:eb:6f:f9:c9:
    59:c8:30:dc:c2:1b:dc:6c:9d:ea:0c:3d:52:5a:00:
    ea:c9:c9:85:51:21:9f:ec:95:b3:dc:c2:50:21:29:
    c2:64:6c:1e:34:36:d8:61:59:ab:3c:a2:cc:e8:ef:
    57:c3:7f:49:86:be:e3:42:88:1b:39:10:b8:2f:fa:
    81:ef:a0:94:99:0c:71:ae:1e:82:7f:e3:6e:00:6e:
    02:13:66:bb:a9:31:58:ec:90:39:9c:bc:9c:8c:90:
    e9:20:f7:20:8e:d6:a3:a3:df:a2:4a:0f:0f:39:b5:
    57:b9:ef:6a:27:e0:1a:ed:f6:ce:0d:87:cd:43:03:
    bf:67:ef:ff:fd:da:98:cc:22:ab:5e:8d:7b:43:d3:
    90:4d
publicExponent: 65537 (0x10001)
privateExponent:
    66:a4:ce:e3:4f:16:f3:b9:6d:ab:ee:1f:70:b4:68:
    28:4f:5d:fa:7e:71:fa:70:8b:37:3e:1f:30:00:15:
    59:12:b6:89:aa:90:46:7c:65:e9:52:11:6c:c1:68:
    00:2a:ed:c1:98:4d:35:59:2c:70:73:e8:22:ed:a6:
    b8:51:d0:2c:98:9d:58:c3:04:2d:01:5f:cf:93:a4:
    18:70:ae:2b:e3:fc:68:53:78:21:1d:eb:5c:ed:24:
    dc:4d:d8:e2:14:77:46:dd:6c:c5:4b:10:a4:e6:7a:
    71:05:36:44:00:36:ca:75:e8:f1:27:2b:11:16:81:
    42:5e:2e:a5:c6:a3:c9:cd:60:59:ce:72:71:76:c8:
    ca:ba:f0:45:c3:86:07:7b:22:20:c4:74:c6:a8:ab:
    7c:2c:f8:de:ea:25:95:81:79:33:54:67:7b:61:91:
    80:a8:1f:4c:38:32:d4:4d:2e:a8:7d:9b:d4:1a:3e:
    6b:ca:50:3c:a0:61:0e:00:ad:f4:5c:0f:26:1a:59:
    00:3c:bd:ee:c3:e8:d0:b8:9b:0e:44:89:49:d1:24:
    a4:39:15:dc:0e:c5:d5:41:a2:4a:f4:e5:e3:23:c7:
    98:8a:87:f7:18:a6:e2:7b:27:83:f6:fb:62:42:46:
    ae:de:ba:48:ad:07:39:40:da:65:17:d1:d2:ed:df:
    01
prime1:
    00:dd:dc:70:b5:70:ea:10:20:28:40:a0:c3:b8:70:
    6d:3d:84:c0:57:2d:69:fc:e9:d4:55:ed:4f:ac:3d:
    c2:e9:19:49:f0:ab:c6:bd:99:9e:0f:e5:a4:61:d4:
    b3:c5:c2:b1:e4:3a:10:ff:e6:cd:ce:6e:2d:93:bc:
    87:12:92:87:7c:d3:dd:bc:32:54:9e:fa:67:b1:9d:
    e2:27:53:e6:03:a7:22:17:45:63:0d:42:f3:96:5d:
    a3:e0:9c:93:f0:42:8b:bb:95:34:e6:f6:0b:f7:b6:
    c5:59:a0:b5:2a:71:59:c0:f2:7e:bf:95:2d:dd:6d:
    94:23:2a:95:4a:4f:f1:d0:93
prime2:
    00:c4:91:6a:33:1b:db:24:eb:fd:d3:69:e9:3c:e2:
    a2:2d:23:7a:92:65:a8:a0:50:1d:0a:2b:b4:f0:64:
    e4:40:57:f3:dc:f7:65:18:7d:51:75:73:b9:d6:67:
    9b:0e:94:5f:37:02:6c:7f:eb:b9:13:4b:bf:8e:65:
    22:0b:2c:c6:8d:2a:a2:88:ec:21:e3:f9:0b:78:b4:
    1d:d0:44:e6:36:0d:ec:3c:8f:0a:c7:3b:0d:91:65:
    b7:de:a3:c9:a3:2a:8c:7f:1f:a1:d2:6e:9b:ee:23:
    78:c1:30:76:87:af:a8:11:a4:15:b4:54:16:d8:94:
    71:5c:64:30:43:58:b5:07:9f
exponent1:
    2f:91:e8:88:be:e1:30:fb:f4:25:87:52:ef:e5:0b:
    47:39:83:94:2d:a4:a0:19:f2:f1:49:a4:df:a5:8e:
    79:34:76:ea:27:aa:c1:54:82:d3:9d:c5:95:44:6a:
    17:69:1b:83:77:ff:d5:1e:c3:da:13:3d:aa:83:ad:
    e2:89:90:8b:6f:52:07:dc:32:d0:b3:98:30:39:4e:
    18:68:a0:d4:ff:ad:0b:98:51:18:b2:d6:4f:d3:5c:
    23:f8:ee:af:81:55:3c:af:4d:5c:88:3d:20:ac:0b:
    bc:9f:fc:b8:50:fd:91:a5:6d:0f:df:08:aa:85:a8:
    51:b1:fb:b8:a7:53:8e:09
exponent2:
    7d:46:0b:7f:ad:06:19:de:c8:b2:7e:f2:25:5a:6e:
    6f:04:08:6e:da:99:00:2a:6e:87:77:d9:65:c7:76:
    ec:46:e1:64:f6:ca:18:34:6d:c0:c3:d3:31:00:70:
    82:77:2e:c3:59:29:1a:d1:78:ef:02:3c:7f:9c:96:
    78:b6:bd:87:64:1f:97:d1:9d:bb:b3:91:8b:08:87:
    63:9f:35:74:47:a5:41:e7:0b:c0:73:33:2f:71:bb:
    20:0a:14:4c:87:a6:68:b2:19:28:8a:53:98:0e:45:
    3c:22:0d:b8:65:cb:60:0a:c9:c6:56:3d:05:24:7d:
    a6:9b:37:63:04:5a:c3:13
coefficient:
    00:cc:d7:5c:e6:0e:7b:79:d4:cb:4f:6d:82:a7:45:
    90:67:90:dc:d3:83:62:f1:4b:17:43:5c:4a:ea:bf:
    38:25:c3:6f:34:e2:05:91:5e:60:d6:de:6d:07:1a:
    73:71:b3:1d:73:f2:3c:60:ed:ec:42:d4:39:f8:a4:
    ae:d5:aa:40:1e:90:b1:eb:b1:05:a3:2f:03:5f:c6:
    b7:07:4c:df:0f:c4:a9:80:8c:31:f5:e2:01:00:73:
    8a:25:03:84:4e:48:7a:31:8e:e6:b8:04:4c:44:61:
    7d:e4:87:1c:57:4f:45:44:33:bb:f3:ae:1c:d2:e1:
    99:ed:78:29:76:4d:8c:6d:91

与此相关，您从不询问如何使用 RSA 密钥进行加密或解密，但您声称加密和解密问题的答案已显示在您答案中的代码中.

Related, you never ask how to encrypt or decrypt with a RSA key, yet you claim the answer to the encryption and decryption problems is shown in the code in your answer.

你似乎已经把这个问题变成了一个移动目标:) 你应该在 Stack Overflow 上避免这种情况(我认为在那些用户线程论坛中这样做是可以的).在 Stack Overflow 上，你应该问一个单独的问题.

You seem to have made the question a moving target :) You should probably avoid that on Stack Overflow (I think its OK to do in those user thread forums). On Stack Overflow, you should ask a separate question.