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#include "../lib/lib.h"
#include "../lib/lib2.h"
#include "../lib/lib3.h"
#include "../lib/lib4.h"
#include "../lib/lib5.h"
#include "../lib/lib6.h"
int main()
{
struct rsa_key_bignum public, private;
unsigned char *mess = "Love of my live you hurt me. You stolen my heart";
BIGNUM *bn_mess = BN_bin2bn(mess, strlen(mess), NULL);
BIGNUM *encrypted = BN_new();
BIGNUM *decrypted = BN_new();
out = BIO_new(BIO_s_file());
BIO_set_fp(out, stdout, BIO_NOCLOSE);
ctx = BN_CTX_new();
printf("plaintext is: %s\n", mess);
BN_print(out, bn_mess);
rsa_generate_key_bignum(&public, &private);
rsa_encrypt_bignum(bn_mess, encrypted, &public);
printf("\nencrpyted message is:\n");
BN_print(out, encrypted);
BIGNUM *S = BN_new();
// genrate random value mod N
BN_pseudo_rand(S, 256, -1, -1);
BN_nnmod(S, S, public.modulo, ctx);
BIGNUM *C_ = BN_new();
BIGNUM *tmp = BN_new();
BN_mod_exp(tmp, S, public.exponent, public.modulo, ctx);
BN_mod_mul(C_, tmp, encrypted, public.modulo, ctx);
printf("\nmodified ciphertext for decryption is:\n");
BN_print(out, C_);
// ok submit this totally differen ciphertext for decryption
rsa_decrypt_bignum(C_, decrypted, &private);
// multiply by modinv of s
modular_multiplicative_inverse_bignum_my(tmp, S, public.modulo);
BN_mod_mul(tmp, decrypted, tmp, public.modulo, ctx);
printf("\nrecovered plaintext is:\n");
BN_print(out, tmp);
printf("\n");
unsigned char *__dec = malloc(strlen(mess));
memset(__dec, 0, strlen(mess));
BN_bn2bin(tmp, __dec);
printf("recovered plaintext: %s\n", __dec);
}
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