completed challenge 40, set 5

1 files changed, 72 insertions, 0 deletions

diff --git a/set5/task40.c b/set5/task40.c
new file mode 100644
index 0000000..42ce66e
--- /dev/null
+++ b/set5/task40.c
@@ -0,0 +1,72 @@
+#include "../lib/lib.h"
+#include "../lib/lib2.h"
+#include "../lib/lib3.h"
+#include "../lib/lib4.h"
+#include "../lib/lib5.h"
+
+int main()
+{
+	int i;
+	struct rsa_key_bignum private[3];
+	struct rsa_key_bignum public[3];
+	BIGNUM *res = BN_new();
+	BIGNUM *encrypted[3];
+	BIGNUM *decrypted = BN_new();
+	BIGNUM *ab[3];
+	BIGNUM *nb[3];
+	BIGNUM *solution_no_mod = BN_new();
+
+	out = BIO_new(BIO_s_file());
+	BIO_set_fp(out, stdout, BIO_NOCLOSE);
+
+	ctx = BN_CTX_new();
+
+	printf("encrypt the following message with three different keys:\n");
+	unsigned char *mess = "All you need is love! Love is all you need";
+	printf("%s\n", mess);
+
+	for(i=0;i<2;i++) {
+		rsa_generate_key_bignum(&public[i], &private[i]);
+		do {
+			rsa_generate_key_bignum(&public[i+1], &private[i+1]);
+		} while (!BN_cmp(private[i].exponent, private[i+1].exponent));
+	}
+
+	printf("private keys:\n");
+	for(i=0;i<3;i++) {
+		BN_print(out, private[i].exponent);
+		printf("\n");
+	}
+
+	BIGNUM *message = BN_bin2bn(mess, strlen(mess), NULL);
+	printf("message as BN:\n");
+	BN_print(out, message);
+	printf("\nencrypted rsa messages:\n");
+	for(i=0;i<3;i++) {
+		encrypted[i] = BN_new();
+		if(!rsa_encrypt_bignum(message, encrypted[i], &public[i]))
+			die("could not rsa encrypt message");
+
+		BN_print(out, encrypted[i]);
+		printf("\n");
+	}
+
+	for(i=0;i<3;i++) {
+		ab[i] = BN_new();
+		nb[i] = BN_new();
+		BN_copy(ab[i], encrypted[i]);
+		BN_copy(nb[i], public[i].modulo);
+	}
+
+	BIGNUM *n_3 = BN_new();
+	BN_set_word(n_3, 3);
+	
+	rsa_broadcast_cube(res, ab, nb);
+	printf("\nrsa broadcast cube is\n");
+	BN_print(out, res);
+	printf("\noriginal message is:\n");
+	BN_print(out, message);
+	unsigned char *__dec = malloc(1000);
+	BN_bn2bin(res, __dec);	
+	printf("\ndecrypted text with rsa broadcast attack: %s\n", __dec);
+}