在C++中將PEM轉換爲DER

Question

我有一個PEM格式的證書，我想使用C++中的OpenSLL函數將其轉換爲DER格式。

我該怎麼辦？

謝謝。

Answer 1

你可以不喜歡它 -

#include <stdio.h> 
#include <openssl/x509.h> 
#include <openssl/pem.h> 
#include <openssl/err.h> 

void convert(char* cert_filestr,char* certificateFile) 
{ 
    X509* x509 = NULL; 
    FILE* fd = NULL,*fl = NULL; 

    fl = fopen(cert_filestr,"rb"); 
    if(fl) 
    { 
     fd = fopen(certificateFile,"w+"); 
     if(fd) 
     { 
      x509 = PEM_read_X509(fl,&x509,NULL,NULL); 
      if(x509) 
      { 
       i2d_X509_fp(fd, x509); 
      } 
      else 
      { 
       printf("failed to parse to X509 from fl"); 
      } 
      fclose(fd); 
     } 
     else 
     { 
      printf("can't open fd"); 
     } 
     fclose(fl); 
    } 
    else 
    { 
     printf("can't open f"); 
    } 
} 


int main() 
{ 
    convert("abc.pem","axc.der"); 
    return 0; 
} 

Answer 2

試試這個 -

void convert(const unsigned char * pem_string_cert,char* certificateFile) 
{ 
    X509* x509 = NULL; 
    FILE* fd = NULL; 

    BIO *bio; 

    bio = BIO_new(BIO_s_mem()); 
    BIO_puts(bio, pem_string_cert); 
    x509 = PEM_read_bio_X509(bio, NULL, NULL, NULL); 

    fd = fopen(certificateFile,"w+"); 
    if(fd) 
    { 
      i2d_X509_fp(fd, x509); 
    } 
    else 
    { 
     printf("can't open fd"); 
    } 
    fclose(fd); 
}