OPENSSL PKCS#7(信封&解信封)

  1 // TestOpensslP7Envelope.cpp : 定义控制台应用程序的入口点。
  2 //
  3 
  4 #include "stdio.h"
  5 #include "string.h"
  6 #include "stdlib.h"
  7 
  8 #include <openssl/pem.h>
  9 #include <openssl/pkcs7.h>
 10 #include <openssl/objects.h>
 11 #include <openssl/x509.h>
 12 
 13 
 14 
 15 int main()
 16 {
 17 
 18 
 19     EVP_PKEY *priKey;
 20 
 21     //读取公钥证书
 22 
 23     char buf[4096];
 24     unsigned char *p;
 25     char *DerPathCharp = "/Users/ipc/Desktop/openssl/rsa_encode_decode/CryptoDemo/yaclifecert.der";
 26 
 27     FILE* fp=fopen(DerPathCharp,"rb");
 28 
 29     if(!fp) 
 30         return NULL;
 31 
 32     int len=fread(buf,1,4096,fp);
 33 
 34     fclose(fp);
 35 
 36 
 37     p=(unsigned char *)buf;
 38 
 39     X509 *x509_Cert=X509_new();
 40 
 41     d2i_X509(&x509_Cert,(const unsigned char **)&p,len);    
 42 
 43 
 44     //调用openssl的代码如下：
 45 
 46     PKCS7* p7 = PKCS7_new();
 47 
 48 
 49     //设置类型为NID_pkcs7_enveloped
 50 
 51     PKCS7_set_type(p7, NID_pkcs7_enveloped);
 52 
 53     //DES算法，用于加密内容“How are you!”
 54 
 55     const EVP_CIPHER *evp_cipher = EVP_des_cbc();
 56 
 57     PKCS7_set_cipher(p7,evp_cipher);
 58 
 59 
 60 
 61     //设置接收者证书，获取公钥用于加密对称密钥
 62 
 63     PKCS7_RECIP_INFO *p7recipinfo = PKCS7_add_recipient(p7,x509_Cert);
 64 
 65     BIO *p7bio = PKCS7_dataInit(p7, NULL);
 66     char *instr = "How Are You!";
 67     BIO_write(p7bio,instr,strlen(instr));
 68 
 69 
 70     printf("instr = %s",instr);
 71     //完成数字信封的运算
 72     BIO_flush(p7bio);
 73 
 74     PKCS7_dataFinal(p7, p7bio);
 75 
 76     //转换PKCS7结构体为DER编码
 77     //X509* derTmp,*der;
 78     int derLen = i2d_PKCS7(p7,NULL);
 79     const unsigned char * der  = (unsigned char*)malloc(derLen);
 80     
 81     unsigned char * derTmp =(unsigned char*)der;
 82     //转换为der编码输出
 83     derLen = i2d_PKCS7(p7,&derTmp);
 84 
 85 
 86     BIO_free(p7bio);
 87 
 88     PKCS7_free(p7);     
 89 
 90 
 91 
 92 
 93 
 94 
 95 
 96 
 97     //解P7数字信封的代码：
 98 
 99     //der编码转换为PKCS7结构体
100     int derP7EnvelopedDataLen = derLen;
101     PKCS7* v_p7 = NULL;
102 
103     PKCS7* v_p7_tmp = d2i_PKCS7(&v_p7,&der,derP7EnvelopedDataLen);
104 
105 
106 
107     //解析出原始数据, evp_key:接收者私钥，x509_cert:接收者证书
108     BIO * v_p7bio_tmp = BIO_new(BIO_s_file());
109     BIO * v_p7bio = PKCS7_dataDecode(v_p7,priKey,NULL,x509_Cert);
110 
111     //从BIO中读取原始数据,将得到"How are you!"
112     char src[4096];
113     int srcLen = BIO_read(v_p7bio,src,4096);
114 
115     printf("\nsrc = %s",src);
116     if (!strcmp(instr,src))
117     {
118         printf(" \n ssl_PKCS7_get_Enveloped_data ok !!\n");
119     }
120 
121     BIO_free(v_p7bio);
122 
123     PKCS7_free(v_p7);
124     return NULL;
125 }