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;
}
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;
}
