openssl pem 生成公钥和私钥及文件

openssl pem.h 中提供了关于pem格式密钥对的操作接口

通常使用.pem的格式文件来保存openssl 生成的密钥对；

在终端下 cat xxx.pem 可以看到 

-----BEGIN RSA PRIVATE KEY-----

XXXX

-----END RSA PRIVATE KEY-----

密钥数据进行了BASE64编码

1. 示例：将生成的密钥对保存成pem文件

按 Ctrl+C 复制代码

按 Ctrl+C 复制代码

 在目标路径保存了生成的公钥opub.pem和私钥oprov.pem

 输出日志

Private-Key: (512 bit)
modulus: 00:e6:96:f5:6f:4d:5e:c2:ad:0d:f5:13:45:99:55:
    ca:6f:84:4f:3a:56:52:e2:ee:a2:cc:73:77:07:e2:
    3d:0d:e3:0d:c0:6a:92:52:b6:c7:de:e2:d6:88:56:
    9e:92:99:91:dd:2d:06:c5:a8:f2:c1:79:8b:20:f9: 73:0a:7a:28:93 publicExponent: 65537 (0x10001)
privateExponent: 00:ca:1b:92:6f:c5:de:c2:bf:2f:b6:98:f7:ad:d8: 16:20:fc:54:fd:0a:e0:87:6b:26:62:10:ea:49:8c:
    b0:7a:d3:d8:28:b7:fb:15:f1:4e:95:9d:bf:31:3a:
    e0:f3:fa:24:d3:71:fd:b0:f5:cd:5c:25:d1:81:8c: 01:e3:fb:c7:21 prime1: 00:f6:d7:91:c4:1a:2f:eb:0b:c4:18:14:3b:fe:f6:
    0d:c1:11:94:ca:6c:06:fc:de:d7:19:ac:58:9d:36: 16:fe:9b
prime2: 00:ef:25:07:75:76:4d:ac:19:aa:ed:e9:a7:1d:5d:
    b1:7d:1c:1a:ef:95:8f:2d:bc:8a:e7:93:f5:f8:15: 69:61:69 exponent1: 00:f4:d2:c0:6f:b8:ed:77:fa:16:87:2f:62:86:31:
    b3:58:9f:c0:6c:b8:92:81:b1:df:b4:45:fd:2a:08: 60:ec:2b
exponent2: 00:b5:88:c1:69:bc:3d:67:f8:30:15:db:f9:5c:c4: 63:d8:59:fe:64:82:7e:a6:b4:6a:29:32:db:53:d0: 45:27:89 coefficient:
    0a:97:26:2f:e9:ca:b6:32:86:86:3b:5a:13:ea:5e:
    8d:79:77:b9:7a:30:41:c4:31:cb:02:0e:96:6b:1b:
    e5:c4
writepri:1 writepub:1 Program ended with exit code: 0

 

2. 示例：从pem文件中获取公钥私钥方式一（利用了BIO）

按 Ctrl+C 复制代码

按 Ctrl+C 复制代码

 从目标路径读取公钥opub.pem和私钥opriv.pem

 输出日志

View Code

 

3. 示例：从pem文件中读取公钥私钥方式二(利用FILE)

void testPEMReadRSA()
{
    RSA *pubkey = RSA_new();
    RSA *prikey = RSA_new();
    
    FILE *pubf = fopen("/Users/cocoajin/Desktop/opub.pem", "rb");
    pubkey = PEM_read_RSAPublicKey(pubf, &pubkey, NULL, NULL);
    
    FILE *prif = fopen("/Users/cocoajin/Desktop/opriv.pem", "rb");
    prikey = PEM_read_RSAPrivateKey(prif, &prikey, NULL, NULL);
    
    RSA_print_fp(stdout, pubkey, 0);
    RSA_print_fp(stdout, prikey, 0);

    fclose(pubf);
    fclose(prif);
    RSA_free(pubkey);
    RSA_free(prikey);


}

 输出日志 

View Code

 

4. 在终端下使用openssl命令生成公钥私钥

//生成1024位的RSA私钥 openssl genrsa -out private.pem 1024 //再由私钥生成公钥 openssl rsa -in private.pem -pubout -out public.pem //私钥文件private.pem //公钥文件public.pem //上面私钥是没加密的，可选加密，指定一个加密算法生成时输入密码

 

以上测试使用openssl 1.1.0c

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