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s/k/shares_required/
[shamirs]
/
shamirssecret.c
diff --git
a/shamirssecret.c
b/shamirssecret.c
index 617f959cd1f846ecd2b42934b2b7b9bb9fd8b1d2..80f835c46318bb2ab825a40135af853d51b96821 100644
(file)
--- a/
shamirssecret.c
+++ b/
shamirssecret.c
@@
-102,6
+102,11
@@
static uint8_t field_pow_ret(uint8_t calc, uint8_t a, uint8_t e) {
return ret;
}
static uint8_t field_pow(uint8_t a, uint8_t e) {
return ret;
}
static uint8_t field_pow(uint8_t a, uint8_t e) {
+#ifndef TEST
+ // Although this function works for a==0, its not trivially obvious why,
+ // and since we never call with a==0, we just assert a != 0 (except when testing)
+ assert(a != 0);
+#endif
return field_pow_ret(exp[(log[a] * e) % 255], a, e);
}
return field_pow_ret(exp[(log[a] * e) % 255], a, e);
}
@@
-125,7
+130,7
@@
static uint8_t field_mul_calc(uint8_t a, uint8_t b) {
static uint8_t field_pow_calc(uint8_t a, uint8_t e) {
uint8_t ret = 1;
for (uint8_t i = 0; i < e; i++)
static uint8_t field_pow_calc(uint8_t a, uint8_t e) {
uint8_t ret = 1;
for (uint8_t i = 0; i < e; i++)
- ret = field_mul(ret, a);
+ ret = field_mul
_calc
(ret, a);
return ret;
}
int main() {
return ret;
}
int main() {
@@
-134,7
+139,7
@@
int main() {
assert(field_mul_calc(i, field_invert(i)) == 1);
// Test multiplication with the logarithm tables
assert(field_mul_calc(i, field_invert(i)) == 1);
// Test multiplication with the logarithm tables
- for (uint16_t i = 0; i <
2
; i++) {
+ for (uint16_t i = 0; i <
P
; i++) {
for (uint16_t j = 0; j < P; j++)
assert(field_mul(i, j) == field_mul_calc(i, j));
}
for (uint16_t j = 0; j < P; j++)
assert(field_mul(i, j) == field_mul_calc(i, j));
}
@@
-185,7
+190,7
@@
int main(int argc, char* argv[]) {
assert(mlockall(MCL_CURRENT | MCL_FUTURE) == 0);
char split = 0;
assert(mlockall(MCL_CURRENT | MCL_FUTURE) == 0);
char split = 0;
- uint8_t
n = 0, k
= 0;
+ uint8_t
total_shares = 0, shares_required
= 0;
char* files[P]; uint8_t files_count = 0;
char *in_file = (void*)0, *out_file_param = (void*)0;
char* files[P]; uint8_t files_count = 0;
char *in_file = (void*)0, *out_file_param = (void*)0;
@@
-209,7
+214,7
@@
int main(int argc, char* argv[]) {
if (t <= 0 || t >= P)
ERROREXIT("n must be > 0 and < %u\n", P)
else
if (t <= 0 || t >= P)
ERROREXIT("n must be > 0 and < %u\n", P)
else
-
n
= t;
+
total_shares
= t;
break;
}
case 'k': {
break;
}
case 'k': {
@@
-217,7
+222,7
@@
int main(int argc, char* argv[]) {
if (t <= 0 || t >= P)
ERROREXIT("n must be > 0 and < %u\n", P)
else
if (t <= 0 || t >= P)
ERROREXIT("n must be > 0 and < %u\n", P)
else
-
k
= t;
+
shares_required
= t;
break;
}
case 'i':
break;
}
case 'i':
@@
-241,17
+246,17
@@
int main(int argc, char* argv[]) {
ERROREXIT("getopt failed?\n")
}
if (!(split & 0x2))
ERROREXIT("getopt failed?\n")
}
if (!(split & 0x2))
- ERROREXIT("Must specify
either -c or -s
\n")
+ ERROREXIT("Must specify
one of -c, -s or -?
\n")
split &= 0x1;
if (argc != optind)
ERROREXIT("Invalid argument\n")
if (split) {
split &= 0x1;
if (argc != optind)
ERROREXIT("Invalid argument\n")
if (split) {
- if (!
n || !k
)
+ if (!
total_shares || !shares_required
)
ERROREXIT("n and k must be set.\n")
ERROREXIT("n and k must be set.\n")
- if (
k > n
)
+ if (
shares_required > total_shares
)
ERROREXIT("k must be <= n\n")
if (files_count != 0 || !in_file || !out_file_param)
ERROREXIT("k must be <= n\n")
if (files_count != 0 || !in_file || !out_file_param)
@@
-273,15
+278,15
@@
int main(int argc, char* argv[]) {
fclose(secret_file);
printf("Using secret of length %lu\n", secret_length);
fclose(secret_file);
printf("Using secret of length %lu\n", secret_length);
- uint8_t a[
k], D[n
][secret_length];
+ uint8_t a[
shares_required], D[total_shares
][secret_length];
for (uint32_t i = 0; i < secret_length; i++) {
a[0] = secret[i];
for (uint32_t i = 0; i < secret_length; i++) {
a[0] = secret[i];
- for (uint8_t j = 1; j <
k
; j++)
+ for (uint8_t j = 1; j <
shares_required
; j++)
assert(fread(&a[j], sizeof(uint8_t), 1, random) == 1);
assert(fread(&a[j], sizeof(uint8_t), 1, random) == 1);
- for (uint8_t j = 0; j <
n
; j++)
- D[j][i] = calculateQ(a,
k
, j+1);
+ for (uint8_t j = 0; j <
total_shares
; j++)
+ D[j][i] = calculateQ(a,
shares_required
, j+1);
if (i % 32 == 0 && i != 0)
printf("Finished processing %u bytes.\n", i);
if (i % 32 == 0 && i != 0)
printf("Finished processing %u bytes.\n", i);
@@
-289,7
+294,7
@@
int main(int argc, char* argv[]) {
char out_file_name_buf[strlen(out_file_param) + 4];
strcpy(out_file_name_buf, out_file_param);
char out_file_name_buf[strlen(out_file_param) + 4];
strcpy(out_file_name_buf, out_file_param);
- for (uint8_t i = 0; i <
n
; i++) {
+ for (uint8_t i = 0; i <
total_shares
; i++) {
/*printf("%u-", i);
for (uint8_t j = 0; j < secret_length; j++)
printf("%02x", D[i][j]);
/*printf("%u-", i);
for (uint8_t j = 0; j < secret_length; j++)
printf("%02x", D[i][j]);
@@
-316,21
+321,21
@@
int main(int argc, char* argv[]) {
// Clear sensitive data (No, GCC 4.7.2 is currently not optimizing this out)
memset(secret, 0, sizeof(uint8_t)*secret_length);
// Clear sensitive data (No, GCC 4.7.2 is currently not optimizing this out)
memset(secret, 0, sizeof(uint8_t)*secret_length);
- memset(a, 0, sizeof(uint8_t)*
k
);
+ memset(a, 0, sizeof(uint8_t)*
shares_required
);
memset(in_file, 0, strlen(in_file));
fclose(random);
} else {
memset(in_file, 0, strlen(in_file));
fclose(random);
} else {
- if (!
k
)
+ if (!
shares_required
)
ERROREXIT("k must be set.\n")
ERROREXIT("k must be set.\n")
- if (files_count !=
k
|| in_file || !out_file_param)
+ if (files_count !=
shares_required
|| in_file || !out_file_param)
ERROREXIT("Must not specify -i and must specify -o and exactly k -f <input file>s in combine mode.\n")
ERROREXIT("Must not specify -i and must specify -o and exactly k -f <input file>s in combine mode.\n")
- uint8_t x[
k], q[k
];
- FILE* files_fps[
k
];
+ uint8_t x[
shares_required], q[shares_required
];
+ FILE* files_fps[
shares_required
];
- for (uint8_t i = 0; i <
k
; i++) {
+ for (uint8_t i = 0; i <
shares_required
; i++) {
files_fps[i] = fopen(files[i], "r");
if (!files_fps[i])
ERROREXIT("Couldn't open file %s for reading.\n", files[i])
files_fps[i] = fopen(files[i], "r");
if (!files_fps[i])
ERROREXIT("Couldn't open file %s for reading.\n", files[i])
@@
-342,11
+347,11
@@
int main(int argc, char* argv[]) {
uint32_t i = 0;
while (fread(&q[0], sizeof(uint8_t), 1, files_fps[0]) == 1) {
uint32_t i = 0;
while (fread(&q[0], sizeof(uint8_t), 1, files_fps[0]) == 1) {
- for (uint8_t j = 1; j <
k
; j++) {
+ for (uint8_t j = 1; j <
shares_required
; j++) {
if (fread(&q[j], sizeof(uint8_t), 1, files_fps[j]) != 1)
ERROREXIT("Couldn't read next byte from %s\n", files[j])
}
if (fread(&q[j], sizeof(uint8_t), 1, files_fps[j]) != 1)
ERROREXIT("Couldn't read next byte from %s\n", files[j])
}
- secret[i++] = calculateSecret(x, q,
k
);
+ secret[i++] = calculateSecret(x, q,
shares_required
);
}
printf("Got secret of length %u\n", i);
}
printf("Got secret of length %u\n", i);
@@
-354,16
+359,16
@@
int main(int argc, char* argv[]) {
fwrite(secret, sizeof(uint8_t), i, out_file);
fclose(out_file);
fwrite(secret, sizeof(uint8_t), i, out_file);
fclose(out_file);
- for (uint8_t i = 0; i <
k
; i++)
+ for (uint8_t i = 0; i <
shares_required
; i++)
fclose(files_fps[i]);
// Clear sensitive data (No, GCC 4.7.2 is currently not optimizing this out)
memset(secret, 0, sizeof(uint8_t)*i);
fclose(files_fps[i]);
// Clear sensitive data (No, GCC 4.7.2 is currently not optimizing this out)
memset(secret, 0, sizeof(uint8_t)*i);
- memset(q, 0, sizeof(uint8_t)*
k
);
+ memset(q, 0, sizeof(uint8_t)*
shares_required
);
memset(out_file_param, 0, strlen(out_file_param));
memset(out_file_param, 0, strlen(out_file_param));
- for (uint8_t i = 0; i <
k
; i++)
+ for (uint8_t i = 0; i <
shares_required
; i++)
memset(files[i], 0, strlen(files[i]));
memset(files[i], 0, strlen(files[i]));
- memset(x, 0, sizeof(uint8_t)*
k
);
+ memset(x, 0, sizeof(uint8_t)*
shares_required
);
}
return 0;
}
return 0;