private_decrypt(p1, p2 = v2)
public
Decrypt string, which has been encrypted with the public key, with
the private key. padding defaults to PKCS1_PADDING.
static VALUE
ossl_rsa_private_decrypt(int argc, VALUE *argv, VALUE self)
{
RSA *rsa;
const BIGNUM *rsa_n;
int buf_len, pad;
VALUE str, buffer, padding;
GetRSA(self, rsa);
RSA_get0_key(rsa, &rsa_n, NULL, NULL);
if (!rsa_n)
ossl_raise(eRSAError, "incomplete RSA");
if (!RSA_PRIVATE(self, rsa))
ossl_raise(eRSAError, "private key needed.");
rb_scan_args(argc, argv, "11", &buffer, &padding);
pad = (argc == 1) ? RSA_PKCS1_PADDING : NUM2INT(padding);
StringValue(buffer);
str = rb_str_new(0, RSA_size(rsa));
buf_len = RSA_private_decrypt(RSTRING_LENINT(buffer), (unsigned char *)RSTRING_PTR(buffer),
(unsigned char *)RSTRING_PTR(str), rsa, pad);
if (buf_len < 0) ossl_raise(eRSAError, NULL);
rb_str_set_len(str, buf_len);
return str;
}