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libbb/pw_encrypt_sha: -28 bytes

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Denis Vlasenko 2008-11-13 12:55:11 +00:00
parent 6b1e3d7e73
commit 6bd54d48f4
1 changed files with 9 additions and 11 deletions
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20
libbb/pw_encrypt_sha.c
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@ -196,25 +196,23 @@ do { \
resptr = to64(resptr, w, N); \ resptr = to64(resptr, w, N); \
} while (0) } while (0)
if (is_sha512 == '5') { if (is_sha512 == '5') {
unsigned i = 0; int i = 0;
unsigned j = 10; int j = 10;
unsigned k = 20; int 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) { while (1) {
b64_from_24bit(alt_result[i], alt_result[j], alt_result[k], 4); b64_from_24bit(alt_result[i], alt_result[j], alt_result[k], 4);
if (i == 9) if (i == 9)
break; break;
i += 21; i = (((i >> 4) & 2) + i) & 0x1f; /* if x - 9 produces < 0, subtract 2 more:
j += 21; j = (((j >> 4) & 2) + j) & 0x1f; * ((i >> 8) << 1) is either 0 or binary 111111...1110 */
k += 21; k = (((k >> 4) & 2) + k) & 0x1f; i -= 9; i = (i & 0x1f) + ((i >> 8) << 1);
j -= 9; j = (j & 0x1f) + ((j >> 8) << 1);
k -= 9; k = (k & 0x1f) + ((k >> 8) << 1);
} }
b64_from_24bit(0, alt_result_31, alt_result[30], 3); b64_from_24bit(0, alt_result[31], alt_result[30], 3);
/* was: /* was:
b64_from_24bit(alt_result[0], alt_result[10], alt_result[20], 4); 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); 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[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[3], alt_result[13], alt_result[23], 4);
b64_from_24bit(alt_result[24], alt_result[4], alt_result[14], 4); b64_from_24bit(alt_result[24], alt_result[4], alt_result[14], 4);