Exemple #1
0
static int recreate_password_from_shares(char **pwd, int *pwdlen, int num_of_password_shares) {

	int r, i;
	BIGNUM prime;
	BIGNUM secret;
	BIGNUM *p;
	char inbuf[64];
	char bin[64];
	int binlen = 0;
	char *ip;
	secret_share_t *shares = NULL;
	secret_share_t *sp;

	/*
	 * Initialize prime and secret
	 */
	BN_init(&prime);
	BN_init(&secret);

	// Allocate data buffer for the shares
	shares = malloc(num_of_password_shares * sizeof(secret_share_t));

	printf("\nDeciphering the DKEK for import into the SmartCard-HSM requires %i key custodians", num_of_password_shares);
	printf("\nto present their share. Only the first key custodian needs to enter the public prime.");
	printf("\nPlease remember to present the share id as well as the share value.");
	printf("\n\nPlease enter prime: ");
	memset(inbuf, 0, sizeof(inbuf));
	fgets(inbuf, sizeof(inbuf), stdin);
	binlen = 64;
	sc_hex_to_bin(inbuf, bin, &binlen);
	BN_bin2bn(bin, binlen, &prime);

	sp = shares;
	for (i = 0; i < num_of_password_shares; i++) {
		clearScreen();

		printf("Press <enter> to enter share %i of %i\n\n", i + 1, num_of_password_shares);
		waitForEnterKeyPressed();

		clearScreen();

		BN_init(&(sp->x));
		BN_init(&(sp->y));

		printf("Share %i of %i\n\n", i + 1, num_of_password_shares);

		printf("Please enter share ID: ");
		memset(inbuf, 0, sizeof(inbuf));
		fgets(inbuf, sizeof(inbuf), stdin);
		p = &(sp->x);
		BN_hex2bn(&p, inbuf);

		printf("Please enter share value: ");
		memset(inbuf, 0, sizeof(inbuf));
		fgets(inbuf, sizeof(inbuf), stdin);
		binlen = 64;
		sc_hex_to_bin(inbuf, bin, &binlen);
		BN_bin2bn(bin, binlen, &(sp->y));

		sp++;
	}

	clearScreen();

	r = reconstructSecret(shares, num_of_password_shares, prime, &secret);

	if (r < 0) {
		printf("\nError during reconstruction of secret. Wrong shares?\n");
		return r;
	}

	/*
	 * Encode the secret value
	 */
	ip = inbuf;
	*pwdlen = BN_bn2bin(&secret, ip);
	*pwd = calloc(1, *pwdlen);
	memcpy(*pwd, ip, *pwdlen);

	cleanUpShares(shares, num_of_password_shares);

	BN_clear_free(&prime);
	BN_clear_free(&secret);

	return 0;
}
Exemple #2
0
static int recreate_password_from_shares(char **pwd, int *pwdlen, int num_of_password_shares)
{
	int r, i;
	BIGNUM *prime;
	BIGNUM *secret;
	BIGNUM *p;
	char inbuf[64];
	unsigned char bin[64];
	size_t binlen = 0;
	unsigned char *ip;
	secret_share_t *shares = NULL;
	secret_share_t *sp;

	if (num_of_password_shares < 2) {
		fprintf(stderr, "--pwd-shares-total must 2 or larger\n");
		return -1;
	}

	// Allocate data buffer for the shares
	shares = malloc(num_of_password_shares * sizeof(secret_share_t));
	if (!shares)
		return -1;

	/*
	 * Initialize prime and secret
	 */
	prime = BN_new();
	secret = BN_new();

	printf("\nDeciphering the DKEK for import into the SmartCard-HSM requires %i key custodians", num_of_password_shares);
	printf("\nto present their share. Only the first key custodian needs to enter the public prime.");
	printf("\nPlease remember to present the share id as well as the share value.");
	printf("\n\nPlease enter prime: ");
	memset(inbuf, 0, sizeof(inbuf));
	if (fgets(inbuf, sizeof(inbuf), stdin) == NULL) {
		fprintf(stderr, "Input aborted\n");
		free(shares);
		return -1;
	}
	binlen = 64;
	sc_hex_to_bin(inbuf, bin, &binlen);
	BN_bin2bn(bin, binlen, prime);

	sp = shares;
	for (i = 0; i < num_of_password_shares; i++) {
		clearScreen();

		printf("Press <enter> to enter share %i of %i\n\n", i + 1, num_of_password_shares);
		waitForEnterKeyPressed();

		clearScreen();

		sp->x = BN_new();
		sp->y = BN_new();

		printf("Share %i of %i\n\n", i + 1, num_of_password_shares);

		printf("Please enter share ID: ");
		memset(inbuf, 0, sizeof(inbuf));
		if (fgets(inbuf, sizeof(inbuf), stdin) == NULL) {
			fprintf(stderr, "Input aborted\n");
			free(shares);
			return -1;
		}
		p = (sp->x);
		BN_hex2bn(&p, inbuf);

		printf("Please enter share value: ");
		memset(inbuf, 0, sizeof(inbuf));
		if (fgets(inbuf, sizeof(inbuf), stdin) == NULL) {
			fprintf(stderr, "Input aborted\n");
			free(shares);
			return -1;
		}
		binlen = 64;
		sc_hex_to_bin(inbuf, bin, &binlen);
		BN_bin2bn(bin, binlen, (sp->y));

		sp++;
	}

	clearScreen();

	r = reconstructSecret(shares, num_of_password_shares, prime, secret);

	if (r < 0) {
		printf("\nError during reconstruction of secret. Wrong shares?\n");
		cleanUpShares(shares, num_of_password_shares);
		return r;
	}

	/*
	 * Encode the secret value
	 */
	ip = (unsigned char *) inbuf;
	*pwdlen = BN_bn2bin(secret, ip);
	*pwd = calloc(1, *pwdlen);
	if (*pwd) {
		memcpy(*pwd, ip, *pwdlen);
	}

	cleanUpShares(shares, num_of_password_shares);

	BN_clear_free(prime);
	BN_clear_free(secret);

	return *pwd ? 0 : -1;
}