crypto/openssl/demos/eay/loadrsa.c

   1 #include <stdio.h>
   2 #include <openssl/rsa.h>
   3
   4 /* This is a simple program to generate an RSA private key.  It then
   5  * saves both the public and private key into a char array, then
   6  * re-reads them.  It saves them as DER encoded binary data.
   7  */
   8
   9 void callback(stage,count,arg)
  10 int stage,count;
  11 char *arg;
  12         {
  13         FILE *out;
  14
  15         out=(FILE *)arg;
  16         fprintf(out,"%d",stage);
  17         if (stage == 3)
  18                 fprintf(out,"\n");
  19         fflush(out);
  20         }
  21
  22 main()
  23         {
  24         RSA *rsa,*pub_rsa,*priv_rsa;
  25         int len;
  26         unsigned char buf[1024],*p;
  27
  28         rsa=RSA_generate_key(512,RSA_F4,callback,(char *)stdout);
  29
  30         p=buf;
  31
  32         /* Save the public key into buffer, we know it will be big enough
  33          * but we should really check how much space we need by calling the
  34          * i2d functions with a NULL second parameter */
  35         len=i2d_RSAPublicKey(rsa,&p);
  36         len+=i2d_RSAPrivateKey(rsa,&p);
  37
  38         printf("The public and private key are now both in a char array\n");
  39         printf("and are taking up %d bytes\n",len);
  40
  41         RSA_free(rsa);
  42
  43         p=buf;
  44         pub_rsa=d2i_RSAPublicKey(NULL,&p,(long)len);
  45         len-=(p-buf);
  46         priv_rsa=d2i_RSAPrivateKey(NULL,&p,(long)len);
  47
  48         if ((pub_rsa == NULL) || (priv_rsa == NULL))
  49                 ERR_print_errors_fp(stderr);
  50
  51         RSA_free(pub_rsa);
  52         RSA_free(priv_rsa);
  53         }