libbb: sha_crypt -123 bytes

This commit is contained in:
Denis Vlasenko 2008-11-13 13:25:18 +00:00
parent 6bd54d48f4
commit 3470f9297e

View File

@ -26,16 +26,22 @@ sha_crypt(/*const*/ char *key_data, /*const*/ char *salt_data)
char *result, *resptr;
/* btw, sha256 needs [32] and uint32_t only */
unsigned char alt_result[64] __attribute__((__aligned__(__alignof__(uint64_t))));
unsigned char temp_result[64] __attribute__((__aligned__(__alignof__(uint64_t))));
union {
sha256_ctx_t x;
sha512_ctx_t y;
} ctx;
union {
sha256_ctx_t x;
sha512_ctx_t y;
} alt_ctx;
struct {
unsigned char alt_result[64];
unsigned char temp_result[64];
union {
sha256_ctx_t x;
sha512_ctx_t y;
} ctx;
union {
sha256_ctx_t x;
sha512_ctx_t y;
} alt_ctx;
} L __attribute__((__aligned__(__alignof__(uint64_t))));
#define alt_result (L.alt_result )
#define temp_result (L.temp_result)
#define ctx (L.ctx )
#define alt_ctx (L.alt_ctx )
unsigned salt_len;
unsigned key_len;
unsigned cnt;
@ -186,7 +192,6 @@ sha_crypt(/*const*/ char *key_data, /*const*/ char *salt_data)
sha_end(alt_result, &ctx);
}
/* Append encrypted password to result buffer */
//TODO: replace with something like
// bb_uuencode(cp, src, length, bb_uuenc_tbl_XXXbase64);
@ -196,18 +201,16 @@ do { \
resptr = to64(resptr, w, N); \
} while (0)
if (is_sha512 == '5') {
int i = 0;
int j = 10;
int k = 20;
unsigned i = 0;
while (1) {
unsigned j = i + 10;
unsigned k = i + 20;
if (j >= 30) j -= 30;
if (k >= 30) k -= 30;
b64_from_24bit(alt_result[i], alt_result[j], alt_result[k], 4);
if (i == 9)
if (k == 29)
break;
/* if x - 9 produces < 0, subtract 2 more:
* ((i >> 8) << 1) is either 0 or binary 111111...1110 */
i -= 9; i = (i & 0x1f) + ((i >> 8) << 1);
j -= 9; j = (j & 0x1f) + ((j >> 8) << 1);
k -= 9; k = (k & 0x1f) + ((k >> 8) << 1);
i = k + 1;
}
b64_from_24bit(0, alt_result[31], alt_result[30], 3);
/* was:
@ -225,15 +228,15 @@ do { \
*/
} else {
unsigned i = 0;
unsigned j = 21;
unsigned k = 42;
while (1) {
unsigned j = i + 21;
unsigned k = i + 42;
if (j >= 63) j -= 63;
if (k >= 63) k -= 63;
b64_from_24bit(alt_result[i], alt_result[j], alt_result[k], 4);
if (i == 62)
if (j == 20)
break;
i += 22; i = ((i >> 6) + i) & 0x3f;
j += 22; j = ((j >> 6) + j) & 0x3f;
k += 22; k = ((k >> 6) + k) & 0x3f;
i = j + 1;
}
b64_from_24bit(0, 0, alt_result[63], 2);
/* was:
@ -267,10 +270,7 @@ do { \
/* Clear the buffer for the intermediate result so that people
attaching to processes or reading core dumps cannot get any
information. */
memset(temp_result, 0, sizeof(temp_result));
memset(alt_result, 0, sizeof(alt_result));
memset(&ctx, 0, sizeof(ctx));
memset(&alt_ctx, 0, sizeof(alt_ctx));
memset(&L, 0, sizeof(L)); /* [alt]_ctx and XXX_result buffers */
memset(key_data, 0, key_len); /* also p_bytes */
memset(salt_data, 0, salt_len); /* also s_bytes */
free(key_data);
@ -279,4 +279,8 @@ do { \
#undef s_bytes
return result;
#undef alt_result
#undef temp_result
#undef ctx
#undef alt_ctx
}