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libbb: remove glibc-style bloat from sha_crypt. -1130 bytes.

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cryptpw: add more difficult test vectors.
This commit is contained in:
Denis Vlasenko
2008-11-13 12:23:46 +00:00
parent 4d47692fb8
commit 6b1e3d7e73
2 changed files with 44 additions and 6 deletions
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41
libbb/pw_encrypt_sha.c
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@@ -57,14 +57,16 @@ sha_crypt(/*const*/ char *key_data, /*const*/ char *salt_data)
if (strncmp(salt_data, str_rounds, 7) == 0) {
/* 7 == strlen("rounds=") */
char *endp;
unsigned srounds = bb_strtou(salt_data + 7, &endp, 10);
cnt = bb_strtou(salt_data + 7, &endp, 10);
if (*endp == '$') {
salt_data = endp + 1;
rounds = srounds;
rounds = cnt;
if (rounds < ROUNDS_MIN)
rounds = ROUNDS_MIN;
if (rounds > ROUNDS_MAX)
rounds = ROUNDS_MAX;
/* add "rounds=NNNNN$" to result */
resptr += sprintf(resptr, str_rounds, rounds);
}
}
salt_len = strchrnul(salt_data, '$') - salt_data;
@@ -73,8 +75,7 @@ sha_crypt(/*const*/ char *key_data, /*const*/ char *salt_data)
/* xstrdup assures suitable alignment; also we will use it
as a scratch space later. */
salt_data = xstrndup(salt_data, salt_len);
if (rounds != ROUNDS_DEFAULT) /* add "rounds=NNNNN$" */
resptr += sprintf(resptr, str_rounds, rounds);
/* add "salt$" to result */
strcpy(resptr, salt_data);
resptr += salt_len;
*resptr++ = '$';
@@ -195,8 +196,25 @@ do { \
resptr = to64(resptr, w, N); \
} while (0)
if (is_sha512 == '5') {
unsigned i = 0;
unsigned j = 10;
unsigned k = 20;
/* strange swap of one byte (see below why) */
unsigned char alt_result_31 = alt_result[31];
alt_result[31] = alt_result[1];
while (1) {
b64_from_24bit(alt_result[i], alt_result[j], alt_result[k], 4);
if (i == 9)
break;
i += 21; i = (((i >> 4) & 2) + i) & 0x1f;
j += 21; j = (((j >> 4) & 2) + j) & 0x1f;
k += 21; k = (((k >> 4) & 2) + k) & 0x1f;
}
b64_from_24bit(0, alt_result_31, alt_result[30], 3);
/* was:
b64_from_24bit(alt_result[0], alt_result[10], alt_result[20], 4);
b64_from_24bit(alt_result[21], alt_result[1], alt_result[11], 4);
...............................^^^^^^^^^^^^^ why [1] and not [31]?
b64_from_24bit(alt_result[12], alt_result[22], alt_result[2], 4);
b64_from_24bit(alt_result[3], alt_result[13], alt_result[23], 4);
b64_from_24bit(alt_result[24], alt_result[4], alt_result[14], 4);
@@ -206,7 +224,21 @@ do { \
b64_from_24bit(alt_result[18], alt_result[28], alt_result[8], 4);
b64_from_24bit(alt_result[9], alt_result[19], alt_result[29], 4);
b64_from_24bit(0, alt_result[31], alt_result[30], 3);
*/
} else {
unsigned i = 0;
unsigned j = 21;
unsigned k = 42;
while (1) {
b64_from_24bit(alt_result[i], alt_result[j], alt_result[k], 4);
if (i == 62)
break;
i += 22; i = ((i >> 6) + i) & 0x3f;
j += 22; j = ((j >> 6) + j) & 0x3f;
k += 22; k = ((k >> 6) + k) & 0x3f;
}
b64_from_24bit(0, 0, alt_result[63], 2);
/* was:
b64_from_24bit(alt_result[0], alt_result[21], alt_result[42], 4);
b64_from_24bit(alt_result[22], alt_result[43], alt_result[1], 4);
b64_from_24bit(alt_result[44], alt_result[2], alt_result[23], 4);
@@ -229,6 +261,7 @@ do { \
b64_from_24bit(alt_result[40], alt_result[61], alt_result[19], 4);
b64_from_24bit(alt_result[62], alt_result[20], alt_result[41], 4);
b64_from_24bit(0, 0, alt_result[63], 2);
*/
}
/* *resptr = '\0'; - xzalloc did it */
#undef b64_from_24bit