busybox/libbb/sha1.c
Denis Vlasenko c8329c9568 sha: reduce sha256/512 context size. Make sha1/sha256 code more similar
function                                             old     new   delta
sha512_end                                           182     204     +22
sha256_end                                           137     147     +10
sha1_hash                                            113     108      -5
sha1_end                                             143     129     -14
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/2 up/down: 32/-19)             Total: 13 bytes
2009-03-12 19:06:18 +00:00

610 lines
16 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Based on shasum from http://www.netsw.org/crypto/hash/
* Majorly hacked up to use Dr Brian Gladman's sha1 code
*
* Copyright (C) 2002 Dr Brian Gladman <brg@gladman.me.uk>, Worcester, UK.
* Copyright (C) 2003 Glenn L. McGrath
* Copyright (C) 2003 Erik Andersen
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*
* ---------------------------------------------------------------------------
* Issue Date: 10/11/2002
*
* This is a byte oriented version of SHA1 that operates on arrays of bytes
* stored in memory. It runs at 22 cycles per byte on a Pentium P4 processor
*
* ---------------------------------------------------------------------------
*
* SHA256 and SHA512 parts are:
* Released into the Public Domain by Ulrich Drepper <drepper@redhat.com>.
* Shrank by Denys Vlasenko.
*
* ---------------------------------------------------------------------------
*
* The best way to test random blocksizes is to go to coreutils/md5_sha1_sum.c
* and replace "4096" with something like "2000 + time(NULL) % 2097",
* then rebuild and compare "shaNNNsum bigfile" results.
*/
#include "libbb.h"
#define rotl32(x,n) (((x) << (n)) | ((x) >> (32 - (n))))
#define rotr32(x,n) (((x) >> (n)) | ((x) << (32 - (n))))
/* for sha512: */
#define rotr64(x,n) (((x) >> (n)) | ((x) << (64 - (n))))
#if BB_LITTLE_ENDIAN
static inline uint64_t hton64(uint64_t v)
{
return (((uint64_t)htonl(v)) << 32) | htonl(v >> 32);
}
#else
#define hton64(v) (v)
#endif
#define ntoh64(v) hton64(v)
/* To check alignment gcc has an appropriate operator. Other
compilers don't. */
#if defined(__GNUC__) && __GNUC__ >= 2
# define UNALIGNED_P(p,type) (((uintptr_t) p) % __alignof__(type) != 0)
#else
# define UNALIGNED_P(p,type) (((uintptr_t) p) % sizeof(type) != 0)
#endif
#define SHA1_BLOCK_SIZE 64
#define SHA1_MASK (SHA1_BLOCK_SIZE - 1)
static void sha1_process_block64(sha1_ctx_t *ctx)
{
unsigned i;
uint32_t w[80], a, b, c, d, e, t;
uint32_t *words;
words = (uint32_t*) ctx->wbuffer;
for (i = 0; i < SHA1_BLOCK_SIZE / 4; ++i) {
w[i] = ntohl(*words);
words++;
}
for (/*i = SHA1_BLOCK_SIZE / 4*/; i < 80; ++i) {
t = w[i - 3] ^ w[i - 8] ^ w[i - 14] ^ w[i - 16];
w[i] = rotl32(t, 1);
}
a = ctx->hash[0];
b = ctx->hash[1];
c = ctx->hash[2];
d = ctx->hash[3];
e = ctx->hash[4];
/* Reverse byte order in 32-bit words */
#define ch(x,y,z) ((z) ^ ((x) & ((y) ^ (z))))
#define parity(x,y,z) ((x) ^ (y) ^ (z))
#define maj(x,y,z) (((x) & (y)) | ((z) & ((x) | (y))))
/* A normal version as set out in the FIPS. This version uses */
/* partial loop unrolling and is optimised for the Pentium 4 */
#define rnd(f,k) \
do { \
t = a; a = rotl32(a,5) + f(b,c,d) + e + k + w[i]; \
e = d; d = c; c = rotl32(b, 30); b = t; \
} while (0)
for (i = 0; i < 20; ++i)
rnd(ch, 0x5a827999);
for (/*i = 20*/; i < 40; ++i)
rnd(parity, 0x6ed9eba1);
for (/*i = 40*/; i < 60; ++i)
rnd(maj, 0x8f1bbcdc);
for (/*i = 60*/; i < 80; ++i)
rnd(parity, 0xca62c1d6);
#undef ch
#undef parity
#undef maj
#undef rnd
ctx->hash[0] += a;
ctx->hash[1] += b;
ctx->hash[2] += c;
ctx->hash[3] += d;
ctx->hash[4] += e;
}
/* Constants for SHA256 from FIPS 180-2:4.2.2. */
static const uint32_t K256[80] = {
0x428a2f98, 0x71374491,
0xb5c0fbcf, 0xe9b5dba5,
0x3956c25b, 0x59f111f1,
0x923f82a4, 0xab1c5ed5,
0xd807aa98, 0x12835b01,
0x243185be, 0x550c7dc3,
0x72be5d74, 0x80deb1fe,
0x9bdc06a7, 0xc19bf174,
0xe49b69c1, 0xefbe4786,
0x0fc19dc6, 0x240ca1cc,
0x2de92c6f, 0x4a7484aa,
0x5cb0a9dc, 0x76f988da,
0x983e5152, 0xa831c66d,
0xb00327c8, 0xbf597fc7,
0xc6e00bf3, 0xd5a79147,
0x06ca6351, 0x14292967,
0x27b70a85, 0x2e1b2138,
0x4d2c6dfc, 0x53380d13,
0x650a7354, 0x766a0abb,
0x81c2c92e, 0x92722c85,
0xa2bfe8a1, 0xa81a664b,
0xc24b8b70, 0xc76c51a3,
0xd192e819, 0xd6990624,
0xf40e3585, 0x106aa070,
0x19a4c116, 0x1e376c08,
0x2748774c, 0x34b0bcb5,
0x391c0cb3, 0x4ed8aa4a,
0x5b9cca4f, 0x682e6ff3,
0x748f82ee, 0x78a5636f,
0x84c87814, 0x8cc70208,
0x90befffa, 0xa4506ceb,
0xbef9a3f7, 0xc67178f2,
0xca273ece, 0xd186b8c7, /* [64]+ are used for sha512 only */
0xeada7dd6, 0xf57d4f7f,
0x06f067aa, 0x0a637dc5,
0x113f9804, 0x1b710b35,
0x28db77f5, 0x32caab7b,
0x3c9ebe0a, 0x431d67c4,
0x4cc5d4be, 0x597f299c,
0x5fcb6fab, 0x6c44198c
};
/* Constants for SHA512 from FIPS 180-2:4.2.3. */
static const uint32_t K512_lo[80] = {
0xd728ae22, 0x23ef65cd,
0xec4d3b2f, 0x8189dbbc,
0xf348b538, 0xb605d019,
0xaf194f9b, 0xda6d8118,
0xa3030242, 0x45706fbe,
0x4ee4b28c, 0xd5ffb4e2,
0xf27b896f, 0x3b1696b1,
0x25c71235, 0xcf692694,
0x9ef14ad2, 0x384f25e3,
0x8b8cd5b5, 0x77ac9c65,
0x592b0275, 0x6ea6e483,
0xbd41fbd4, 0x831153b5,
0xee66dfab, 0x2db43210,
0x98fb213f, 0xbeef0ee4,
0x3da88fc2, 0x930aa725,
0xe003826f, 0x0a0e6e70,
0x46d22ffc, 0x5c26c926,
0x5ac42aed, 0x9d95b3df,
0x8baf63de, 0x3c77b2a8,
0x47edaee6, 0x1482353b,
0x4cf10364, 0xbc423001,
0xd0f89791, 0x0654be30,
0xd6ef5218, 0x5565a910,
0x5771202a, 0x32bbd1b8,
0xb8d2d0c8, 0x5141ab53,
0xdf8eeb99, 0xe19b48a8,
0xc5c95a63, 0xe3418acb,
0x7763e373, 0xd6b2b8a3,
0x5defb2fc, 0x43172f60,
0xa1f0ab72, 0x1a6439ec,
0x23631e28, 0xde82bde9,
0xb2c67915, 0xe372532b,
0xea26619c, 0x21c0c207,
0xcde0eb1e, 0xee6ed178,
0x72176fba, 0xa2c898a6,
0xbef90dae, 0x131c471b,
0x23047d84, 0x40c72493,
0x15c9bebc, 0x9c100d4c,
0xcb3e42b6, 0xfc657e2a,
0x3ad6faec, 0x4a475817
};
/* Process LEN bytes of BUFFER, accumulating context into CTX.
LEN is rounded _down_ to 64. */
static void sha256_process_block64(const void *buffer, size_t len, sha256_ctx_t *ctx)
{
const uint32_t *words = buffer;
uint32_t a = ctx->hash[0];
uint32_t b = ctx->hash[1];
uint32_t c = ctx->hash[2];
uint32_t d = ctx->hash[3];
uint32_t e = ctx->hash[4];
uint32_t f = ctx->hash[5];
uint32_t g = ctx->hash[6];
uint32_t h = ctx->hash[7];
/* Process all bytes in the buffer with 64 bytes in each round of
the loop. */
len /= (sizeof(uint32_t) * 16);
while (len) {
unsigned t;
uint32_t W[64];
/* Operators defined in FIPS 180-2:4.1.2. */
#define Ch(x, y, z) ((x & y) ^ (~x & z))
#define Maj(x, y, z) ((x & y) ^ (x & z) ^ (y & z))
#define S0(x) (rotr32(x, 2) ^ rotr32(x, 13) ^ rotr32(x, 22))
#define S1(x) (rotr32(x, 6) ^ rotr32(x, 11) ^ rotr32(x, 25))
#define R0(x) (rotr32(x, 7) ^ rotr32(x, 18) ^ (x >> 3))
#define R1(x) (rotr32(x, 17) ^ rotr32(x, 19) ^ (x >> 10))
/* Compute the message schedule according to FIPS 180-2:6.2.2 step 2. */
for (t = 0; t < 16; ++t) {
W[t] = ntohl(*words);
words++;
}
for (/*t = 16*/; t < 64; ++t)
W[t] = R1(W[t - 2]) + W[t - 7] + R0(W[t - 15]) + W[t - 16];
/* The actual computation according to FIPS 180-2:6.2.2 step 3. */
for (t = 0; t < 64; ++t) {
uint32_t T1 = h + S1(e) + Ch(e, f, g) + K256[t] + W[t];
uint32_t T2 = S0(a) + Maj(a, b, c);
h = g;
g = f;
f = e;
e = d + T1;
d = c;
c = b;
b = a;
a = T1 + T2;
}
#undef Ch
#undef Maj
#undef S0
#undef S1
#undef R0
#undef R1
/* Add the starting values of the context according to FIPS 180-2:6.2.2
step 4. */
ctx->hash[0] = a += ctx->hash[0];
ctx->hash[1] = b += ctx->hash[1];
ctx->hash[2] = c += ctx->hash[2];
ctx->hash[3] = d += ctx->hash[3];
ctx->hash[4] = e += ctx->hash[4];
ctx->hash[5] = f += ctx->hash[5];
ctx->hash[6] = g += ctx->hash[6];
ctx->hash[7] = h += ctx->hash[7];
/* Prepare for the next round. */
len--;
}
}
/* Process LEN bytes of BUFFER, accumulating context into CTX.
LEN is rounded _down_ to 128. */
static void sha512_process_block128(const void *buffer, size_t len, sha512_ctx_t *ctx)
{
const uint64_t *words = buffer;
uint64_t a = ctx->hash[0];
uint64_t b = ctx->hash[1];
uint64_t c = ctx->hash[2];
uint64_t d = ctx->hash[3];
uint64_t e = ctx->hash[4];
uint64_t f = ctx->hash[5];
uint64_t g = ctx->hash[6];
uint64_t h = ctx->hash[7];
len /= (sizeof(uint64_t) * 16);
while (len) {
unsigned t;
uint64_t W[80];
/* Operators defined in FIPS 180-2:4.1.2. */
#define Ch(x, y, z) ((x & y) ^ (~x & z))
#define Maj(x, y, z) ((x & y) ^ (x & z) ^ (y & z))
#define S0(x) (rotr64(x, 28) ^ rotr64(x, 34) ^ rotr64(x, 39))
#define S1(x) (rotr64(x, 14) ^ rotr64(x, 18) ^ rotr64(x, 41))
#define R0(x) (rotr64(x, 1) ^ rotr64(x, 8) ^ (x >> 7))
#define R1(x) (rotr64(x, 19) ^ rotr64(x, 61) ^ (x >> 6))
/* Compute the message schedule according to FIPS 180-2:6.3.2 step 2. */
for (t = 0; t < 16; ++t) {
W[t] = ntoh64(*words);
words++;
}
for (/*t = 16*/; t < 80; ++t)
W[t] = R1(W[t - 2]) + W[t - 7] + R0(W[t - 15]) + W[t - 16];
/* The actual computation according to FIPS 180-2:6.3.2 step 3. */
for (t = 0; t < 80; ++t) {
uint64_t K512_t = ((uint64_t)(K256[t]) << 32) + K512_lo[t];
uint64_t T1 = h + S1(e) + Ch(e, f, g) + K512_t + W[t];
uint64_t T2 = S0(a) + Maj(a, b, c);
h = g;
g = f;
f = e;
e = d + T1;
d = c;
c = b;
b = a;
a = T1 + T2;
}
#undef Ch
#undef Maj
#undef S0
#undef S1
#undef R0
#undef R1
/* Add the starting values of the context according to FIPS 180-2:6.3.2
step 4. */
ctx->hash[0] = a += ctx->hash[0];
ctx->hash[1] = b += ctx->hash[1];
ctx->hash[2] = c += ctx->hash[2];
ctx->hash[3] = d += ctx->hash[3];
ctx->hash[4] = e += ctx->hash[4];
ctx->hash[5] = f += ctx->hash[5];
ctx->hash[6] = g += ctx->hash[6];
ctx->hash[7] = h += ctx->hash[7];
len--;
}
}
void FAST_FUNC sha1_begin(sha1_ctx_t *ctx)
{
ctx->total64 = 0;
ctx->hash[0] = 0x67452301;
ctx->hash[1] = 0xefcdab89;
ctx->hash[2] = 0x98badcfe;
ctx->hash[3] = 0x10325476;
ctx->hash[4] = 0xc3d2e1f0;
}
static const uint32_t init256[] = {
0x6a09e667,
0xbb67ae85,
0x3c6ef372,
0xa54ff53a,
0x510e527f,
0x9b05688c,
0x1f83d9ab,
0x5be0cd19
};
static const uint32_t init512_lo[] = {
0xf3bcc908,
0x84caa73b,
0xfe94f82b,
0x5f1d36f1,
0xade682d1,
0x2b3e6c1f,
0xfb41bd6b,
0x137e2179
};
/* Initialize structure containing state of computation.
(FIPS 180-2:5.3.2) */
void FAST_FUNC sha256_begin(sha256_ctx_t *ctx)
{
memcpy(ctx->hash, init256, sizeof(init256));
ctx->total64 = 0;
}
/* Initialize structure containing state of computation.
(FIPS 180-2:5.3.3) */
void FAST_FUNC sha512_begin(sha512_ctx_t *ctx)
{
int i;
for (i = 0; i < 8; i++)
ctx->hash[i] = ((uint64_t)(init256[i]) << 32) + init512_lo[i];
ctx->total64[0] = ctx->total64[1] = 0;
}
void FAST_FUNC sha1_hash(const void *buffer, size_t len, sha1_ctx_t *ctx)
{
unsigned in_buf = ctx->total64 & SHA1_MASK;
unsigned add = SHA1_BLOCK_SIZE - in_buf;
ctx->total64 += len;
while (len >= add) { /* transfer whole blocks while possible */
memcpy(ctx->wbuffer + in_buf, buffer, add);
buffer = (const char *)buffer + add;
len -= add;
add = SHA1_BLOCK_SIZE;
in_buf = 0;
sha1_process_block64(ctx);
}
memcpy(ctx->wbuffer + in_buf, buffer, len);
}
void FAST_FUNC sha256_hash(const void *buffer, size_t len, sha256_ctx_t *ctx)
{
unsigned in_buf = ctx->total64 & 63;
/* First increment the byte count. FIPS 180-2 specifies the possible
length of the file up to 2^64 _bits_.
We compute the number of _bytes_ and convert to bits later. */
ctx->total64 += len;
/* When we already have some bits in our internal buffer concatenate
both inputs first. */
if (in_buf != 0) {
unsigned add;
add = sizeof(ctx->wbuffer) - in_buf;
if (add > len)
add = len;
memcpy(ctx->wbuffer + in_buf, buffer, add);
in_buf += add;
/* If we still didn't collect full wbuffer, bail out */
if (in_buf < sizeof(ctx->wbuffer))
return;
sha256_process_block64(ctx->wbuffer, 64, ctx);
buffer = (const char *)buffer + add;
len -= add;
}
/* Process available complete blocks. */
if (len >= 64) {
if (UNALIGNED_P(buffer, uint32_t)) {
while (len >= 64) {
sha256_process_block64(memcpy(ctx->wbuffer, buffer, 64), 64, ctx);
buffer = (const char *)buffer + 64;
len -= 64;
}
} else {
sha256_process_block64(buffer, len /*& ~63*/, ctx);
buffer = (const char *)buffer + (len & ~63);
len &= 63;
}
}
/* Move remaining bytes into internal buffer. */
if (len > 0)
memcpy(ctx->wbuffer, buffer, len);
}
void FAST_FUNC sha512_hash(const void *buffer, size_t len, sha512_ctx_t *ctx)
{
unsigned in_buf = ctx->total64[0] & 127;
/* First increment the byte count. FIPS 180-2 specifies the possible
length of the file up to 2^128 _bits_.
We compute the number of _bytes_ and convert to bits later. */
ctx->total64[0] += len;
if (ctx->total64[0] < len)
ctx->total64[1]++;
if (in_buf != 0) {
unsigned add;
add = sizeof(ctx->wbuffer) - in_buf;
if (add > len)
add = len;
memcpy(ctx->wbuffer + in_buf, buffer, add);
in_buf += add;
if (in_buf < sizeof(ctx->wbuffer))
return;
sha512_process_block128(ctx->wbuffer, 128, ctx);
buffer = (const char *)buffer + add;
len -= add;
}
if (len >= 128) {
if (UNALIGNED_P(buffer, uint64_t)) {
while (len >= 128) {
sha512_process_block128(memcpy(ctx->wbuffer, buffer, 128), 128, ctx);
buffer = (const char *)buffer + 128;
len -= 128;
}
} else {
sha512_process_block128(buffer, len /*& ~127*/, ctx);
buffer = (const char *)buffer + (len & ~127);
len &= 127;
}
}
if (len > 0)
memcpy(ctx->wbuffer, buffer, len);
}
void FAST_FUNC sha1_end(void *resbuf, sha1_ctx_t *ctx)
{
unsigned i, pad, in_buf;
in_buf = ctx->total64 & SHA1_MASK;
/* Pad the buffer to the next 64-byte boundary with 0x80,0,0,0... */
ctx->wbuffer[in_buf++] = 0x80;
/* This loop iterates either once or twice, no more, no less */
while (1) {
pad = SHA1_BLOCK_SIZE - in_buf;
memset(ctx->wbuffer + in_buf, 0, pad);
in_buf = 0;
/* Do we have enough space for the length count? */
if (pad >= 8) {
/* Store the 64-bit counter of bits in the buffer in BE format */
uint64_t t = ctx->total64 << 3;
t = hton64(t);
/* wbuffer is suitably aligned for this */
*(uint64_t *) (&ctx->wbuffer[SHA1_BLOCK_SIZE - 8]) = t;
}
sha1_process_block64(ctx);
if (pad >= 8)
break;
}
/* This way we do not impose alignment constraints on resbuf: */
#if BB_LITTLE_ENDIAN
for (i = 0; i < ARRAY_SIZE(ctx->hash); ++i)
ctx->hash[i] = htonl(ctx->hash[i]);
#endif
memcpy(resbuf, ctx->hash, sizeof(ctx->hash));
}
void FAST_FUNC sha256_end(void *resbuf, sha256_ctx_t *ctx)
{
unsigned i, pad, in_buf;
in_buf = ctx->total64 & 63;
/* Pad the buffer to the next 64-byte boundary with 0x80,0,0,0...
* (FIPS 180-2:5.1.1)
*/
ctx->wbuffer[in_buf++] = 0x80;
while (1) {
pad = 64 - in_buf;
memset(ctx->wbuffer + in_buf, 0, pad);
in_buf = 0;
if (pad >= 8) {
uint64_t t = ctx->total64 << 3;
t = hton64(t);
*(uint64_t *) (&ctx->wbuffer[64 - 8]) = t;
}
sha256_process_block64(ctx->wbuffer, 64, ctx);
if (pad >= 8)
break;
}
#if BB_LITTLE_ENDIAN
for (i = 0; i < ARRAY_SIZE(ctx->hash); ++i)
ctx->hash[i] = htonl(ctx->hash[i]);
#endif
memcpy(resbuf, ctx->hash, sizeof(ctx->hash));
}
void FAST_FUNC sha512_end(void *resbuf, sha512_ctx_t *ctx)
{
unsigned i, pad, in_buf;
in_buf = ctx->total64[0] & 127;
/* Pad the buffer to the next 128-byte boundary with 0x80,0,0,0...
* (FIPS 180-2:5.1.2)
*/
ctx->wbuffer[in_buf++] = 0x80;
while (1) {
pad = 128 - in_buf;
memset(ctx->wbuffer + in_buf, 0, pad);
in_buf = 0;
if (pad >= 16) {
/* Store the 128-bit counter of bits in the buffer in BE format */
uint64_t t;
t = ctx->total64[0] << 3;
t = hton64(t);
*(uint64_t *) (&ctx->wbuffer[128 - 8]) = t;
t = (ctx->total64[1] << 3) | (ctx->total64[0] >> 61);
t = hton64(t);
*(uint64_t *) (&ctx->wbuffer[128 - 16]) = t;
}
sha512_process_block128(ctx->wbuffer, 128, ctx);
if (pad >= 16)
break;
}
#if BB_LITTLE_ENDIAN
for (i = 0; i < ARRAY_SIZE(ctx->hash); ++i)
ctx->hash[i] = hton64(ctx->hash[i]);
#endif
memcpy(resbuf, ctx->hash, sizeof(ctx->hash));
}