[openssl-users] error making Private RSA

[Matt Caswell]

On 02/03/17 00:47, william estrada wrote:
> Hello group,
> I am attempting to create a Private RSA structure with the following code:
>  BIO*
>   PEM = BIO_new_mem_buf( Key, Key_Len );
> 
>   if( Type == 1 )
>      PEM_write_bio_RSAPrivateKey( PEM, RSA, NULL, NULL, 0, NULL, NULL );
>   else
>      PEM_write_bio_RSAPublicKey(  PEM, RSA );
> 
>   if( RSA_check_key( RSA ) != 1 )  {
>     printf( RED "Make %s RSA Failed\n" OFF, Type==1?"Private":"Public" );
>     int Error  = ERR_get_error();
>     char *MSG  = ERR_error_string( Error, NULL);
>     printf( "%s\n", MSG );  }
> 
> and I get this error:
> Make Private RSA Failed
> error:2007507E:lib(32):func(117):reason(126)
> Can anyone tell me what this error is and how to fix it?
> 
> 

$ openssl errstr 2007507E
error:2007507E:BIO routines:mem_write:write to read only BIO

BIO_new_mem_buf() gives you a read-only BIO. You probably want
BIO_new(BIO_s_mem()) instead.

See:

https://www.openssl.org/docs/man1.1.0/crypto/BIO_s_mem.html

Although, that error is coming from one of the PEM_write_bio_* calls
(which you are not checking the error return code of), so it doesn't
explain why RSA_check_key() fails. You don't show how you generate the
RSA structure to start with, so I guess you're not generating it properly.

Matt