← Commit list

cd2cd312b

Denis Vlasenko

2009-03-12

FAILED Duration: 36s

Subject

shrink sha hashing a bit more (remove wbuflen field from ctx), remove the requirement for aligned buffer

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

include/libbb.h +2 -4 libbb/md5.c +9 -10 libbb/sha1.c +102 -122

include/libbb.h+2 -4

@@ -1329,18 +1329,16 @@ void sha1_begin(sha1_ctx_t *ctx) FAST_FUNC;
	void sha1_hash(const void data, size_t length, sha1_ctx_t ctx) FAST_FUNC;
	void sha1_end(void resbuf, sha1_ctx_t ctx) FAST_FUNC;
	typedef struct sha256_ctx_t {
-	unsigned wbuflen;
-	uint32_t H[8];
	uint64_t total64;
+	uint32_t hash[8];
	char wbuffer[642]; / NB: always correctly aligned for uint64_t */
	} sha256_ctx_t;
	void sha256_begin(sha256_ctx_t *ctx) FAST_FUNC;
	void sha256_hash(const void buffer, size_t len, sha256_ctx_t ctx) FAST_FUNC;
	void sha256_end(void resbuf, sha256_ctx_t ctx) FAST_FUNC;
	typedef struct sha512_ctx_t {
-	unsigned wbuflen;
-	uint64_t H[8];
	uint64_t total64[2];
+	uint64_t hash[8];
	char wbuffer[1282]; / NB: always correctly aligned for uint64_t */
	} sha512_ctx_t;
	void sha512_begin(sha512_ctx_t *ctx) FAST_FUNC;

libbb/md5.c+9 -10

@@ -416,15 +416,14 @@ void FAST_FUNC md5_end(void resbuf, md5_ctx_t ctx)
	md5_hash_block(ctx->buffer, ctx);
	md5_hash_block(buf, ctx);

-	/* Put result from CTX in first 16 bytes following RESBUF. The result is
-	* always in little endian byte order, so that a byte-wise output yields
-	* to the wanted ASCII representation of the message digest.
-	*
-	* IMPORTANT: On some systems it is required that RESBUF is correctly
-	* aligned for a 32 bits value.
+	/* The MD5 result is in little endian byte order.
+	* We (ab)use the fact that A-D are consecutive in memory.
	*/
-	((uint32_t *) resbuf)[0] = SWAP_LE32(ctx->A);
-	((uint32_t *) resbuf)[1] = SWAP_LE32(ctx->B);
-	((uint32_t *) resbuf)[2] = SWAP_LE32(ctx->C);
-	((uint32_t *) resbuf)[3] = SWAP_LE32(ctx->D);
+	#if BB_BIG_ENDIAN
+	ctx->A = SWAP_LE32(ctx->A);
+	ctx->B = SWAP_LE32(ctx->B);
+	ctx->C = SWAP_LE32(ctx->C);
+	ctx->D = SWAP_LE32(ctx->D);
+	#endif
+	memcpy(resbuf, &ctx->A, sizeof(ctx->A) * 4);
	}

libbb/sha1.c+102 -122

@@ -200,20 +200,14 @@ static const uint32_t K512_lo[80] = {
	static void sha256_process_block64(const void buffer, size_t len, sha256_ctx_t ctx)
	{
	const uint32_t *words = buffer;
-	uint32_t a = ctx->H[0];
-	uint32_t b = ctx->H[1];
-	uint32_t c = ctx->H[2];
-	uint32_t d = ctx->H[3];
-	uint32_t e = ctx->H[4];
-	uint32_t f = ctx->H[5];
-	uint32_t g = ctx->H[6];
-	uint32_t h = ctx->H[7];
-
-	/* 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. */
-	len &= ~(size_t)(sizeof(uint32_t) * 16 - 1);
-	ctx->total64 += len;
+	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. */
@@ -260,14 +254,14 @@ static void sha256_process_block64(const void *buffer, size_t len, sha256_ctx_t
	#undef R1
	/* Add the starting values of the context according to FIPS 180-2:6.2.2
	step 4. */
-	ctx->H[0] = a += ctx->H[0];
-	ctx->H[1] = b += ctx->H[1];
-	ctx->H[2] = c += ctx->H[2];
-	ctx->H[3] = d += ctx->H[3];
-	ctx->H[4] = e += ctx->H[4];
-	ctx->H[5] = f += ctx->H[5];
-	ctx->H[6] = g += ctx->H[6];
-	ctx->H[7] = h += ctx->H[7];
+	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--;
@@ -278,22 +272,14 @@ static void sha256_process_block64(const void *buffer, size_t len, sha256_ctx_t
	static void sha512_process_block128(const void buffer, size_t len, sha512_ctx_t ctx)
	{
	const uint64_t *words = buffer;
-	uint64_t a = ctx->H[0];
-	uint64_t b = ctx->H[1];
-	uint64_t c = ctx->H[2];
-	uint64_t d = ctx->H[3];
-	uint64_t e = ctx->H[4];
-	uint64_t f = ctx->H[5];
-	uint64_t g = ctx->H[6];
-	uint64_t h = ctx->H[7];
-
-	/* 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. */
-	len &= ~(size_t)(sizeof(uint64_t) * 16 - 1);
-	ctx->total64[0] += len;
-	if (ctx->total64[0] < len)
-	ctx->total64[1]++;
+	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) {
@@ -338,14 +324,14 @@ static void sha512_process_block128(const void *buffer, size_t len, sha512_ctx_t
	#undef R1
	/* Add the starting values of the context according to FIPS 180-2:6.3.2
	step 4. */
-	ctx->H[0] = a += ctx->H[0];
-	ctx->H[1] = b += ctx->H[1];
-	ctx->H[2] = c += ctx->H[2];
-	ctx->H[3] = d += ctx->H[3];
-	ctx->H[4] = e += ctx->H[4];
-	ctx->H[5] = f += ctx->H[5];
-	ctx->H[6] = g += ctx->H[6];
-	ctx->H[7] = h += ctx->H[7];
+	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--;
	}
@@ -386,9 +372,8 @@ static const uint32_t init512_lo[] = {
	(FIPS 180-2:5.3.2) */
	void FAST_FUNC sha256_begin(sha256_ctx_t *ctx)
	{
-	memcpy(ctx->H, init256, sizeof(init256));
+	memcpy(ctx->hash, init256, sizeof(init256));
	ctx->total64 = 0;
-	ctx->wbuflen = 0;
	}
	/* Initialize structure containing state of computation.
	(FIPS 180-2:5.3.3) */
@@ -396,9 +381,8 @@ void FAST_FUNC sha512_begin(sha512_ctx_t *ctx)
	{
	int i;
	for (i = 0; i < 8; i++)
-	ctx->H[i] = ((uint64_t)(init256[i]) << 32) + init512_lo[i];
+	ctx->hash[i] = ((uint64_t)(init256[i]) << 32) + init512_lo[i];
	ctx->total64[0] = ctx->total64[1] = 0;
-	ctx->wbuflen = 0;
	}


@@ -406,28 +390,35 @@ void FAST_FUNC sha512_begin(sha512_ctx_t *ctx)
	/* hash_compile function as required. */
	void FAST_FUNC sha1_hash(const void buffer, size_t len, sha1_ctx_t ctx)
	{
-	unsigned wbuflen = ctx->total64 & SHA1_MASK;
-	unsigned add = SHA1_BLOCK_SIZE - wbuflen;
+	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(((unsigned char *) ctx->wbuffer) + wbuflen, buffer, add);
+	memcpy(((unsigned char *) ctx->wbuffer) + in_buf, buffer, add);
	buffer = (const char *)buffer + add;
	len -= add;
	add = SHA1_BLOCK_SIZE;
-	wbuflen = 0;
+	in_buf = 0;
	sha1_process_block64(ctx);
	}

-	memcpy(((unsigned char *) ctx->wbuffer) + wbuflen, buffer, len);
+	memcpy(((unsigned char *) 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 (ctx->wbuflen != 0) {
+	if (in_buf != 0) {
	unsigned add;

	/* NB: 1/2 of wbuffer is used only in sha256_end
@@ -435,18 +426,17 @@ void FAST_FUNC sha256_hash(const void buffer, size_t len, sha256_ctx_t ctx)
	* With buffer twice as small, it may happen that
	* we have it almost full and can't add length field. */

-	add = sizeof(ctx->wbuffer)/2 - ctx->wbuflen;
+	add = sizeof(ctx->wbuffer)/2 - in_buf;
	if (add > len)
	add = len;
-	memcpy(&ctx->wbuffer[ctx->wbuflen], buffer, add);
-	ctx->wbuflen += add;
+	memcpy(&ctx->wbuffer[in_buf], buffer, add);
+	in_buf += add;

	/* If we still didn't collect full wbuffer, bail out */
-	if (ctx->wbuflen < sizeof(ctx->wbuffer)/2)
+	if (in_buf < sizeof(ctx->wbuffer)/2)
	return;

	sha256_process_block64(ctx->wbuffer, 64, ctx);
-	ctx->wbuflen = 0;
	buffer = (const char *)buffer + add;
	len -= add;
	}
@@ -454,7 +444,7 @@ void FAST_FUNC sha256_hash(const void buffer, size_t len, sha256_ctx_t ctx)
	/* Process available complete blocks. */
	if (len >= 64) {
	if (UNALIGNED_P(buffer, uint32_t)) {
-	while (len > 64) {
+	while (len >= 64) {
	sha256_process_block64(memcpy(ctx->wbuffer, buffer, 64), 64, ctx);
	buffer = (const char *)buffer + 64;
	len -= 64;
@@ -469,33 +459,40 @@ void FAST_FUNC sha256_hash(const void buffer, size_t len, sha256_ctx_t ctx)
	/* Move remaining bytes into internal buffer. */
	if (len > 0) {
	memcpy(ctx->wbuffer, buffer, len);
-	ctx->wbuflen = len;
	}
	}

	void FAST_FUNC sha512_hash(const void buffer, size_t len, sha512_ctx_t ctx)
	{
-	if (ctx->wbuflen != 0) {
+	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)/2 - ctx->wbuflen;
+	add = sizeof(ctx->wbuffer)/2 - in_buf;
	if (add > len)
	add = len;
-	memcpy(&ctx->wbuffer[ctx->wbuflen], buffer, add);
-	ctx->wbuflen += add;
+	memcpy(&ctx->wbuffer[in_buf], buffer, add);
+	in_buf += add;

-	if (ctx->wbuflen < sizeof(ctx->wbuffer)/2)
+	if (in_buf < sizeof(ctx->wbuffer)/2)
	return;

	sha512_process_block128(ctx->wbuffer, 128, ctx);
-	ctx->wbuflen = 0;
	buffer = (const char *)buffer + add;
	len -= add;
	}

	if (len >= 128) {
	if (UNALIGNED_P(buffer, uint64_t)) {
-	while (len > 128) {
+	while (len >= 128) {
	sha512_process_block128(memcpy(ctx->wbuffer, buffer, 128), 128, ctx);
	buffer = (const char *)buffer + 128;
	len -= 128;
@@ -509,20 +506,19 @@ void FAST_FUNC sha512_hash(const void buffer, size_t len, sha512_ctx_t ctx)

	if (len > 0) {
	memcpy(ctx->wbuffer, buffer, len);
-	ctx->wbuflen = len;
	}
	}


	void FAST_FUNC sha1_end(void resbuf, sha1_ctx_t ctx)
	{
-	unsigned i, wbuflen, pad;
+	unsigned i, pad, in_buf;

	/* Pad the buffer to the next 64-byte boundary with 0x80,0,0,0... */
-	wbuflen = ctx->total64 & SHA1_MASK;
-	((uint8_t *)ctx->wbuffer)[wbuflen++] = 0x80;
-	pad = SHA1_BLOCK_SIZE - wbuflen;
-	memset(((uint8_t *)ctx->wbuffer) + wbuflen, 0, pad);
+	in_buf = ctx->total64 & SHA1_MASK;
+	((uint8_t *)ctx->wbuffer)[in_buf++] = 0x80;
+	pad = SHA1_BLOCK_SIZE - in_buf;
+	memset(((uint8_t *)ctx->wbuffer) + in_buf, 0, pad);

	/* We need 1+8 or more empty positions, one for the padding byte
	* (above) and eight for the length count.
@@ -543,77 +539,61 @@ void FAST_FUNC sha1_end(void resbuf, sha1_ctx_t ctx)

	sha1_process_block64(ctx);

-	/* Extract the hash value as bytes in case resbuf is
-	* misaligned for 32-bit words */
-	for (i = 0; i < ARRAY_SIZE(ctx->hash); ++i) {
-	uint32_t t = ctx->hash[i];
-	t = ntohl(t); /* paranoia. this can be a macro */
-	move_to_unaligned32(resbuf, t); /* ditto */
-	resbuf = (char*)resbuf + 4;
-	}
+	#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));
	}

-
-	/* Process the remaining bytes in the internal buffer and the usual
-	prolog according to the standard and write the result to RESBUF.
-
-	IMPORTANT: On some systems it is required that RESBUF is correctly
-	aligned for a 32 bits value. */
	void FAST_FUNC sha256_end(void resbuf, sha256_ctx_t ctx)
	{
-	/* Take yet unprocessed bytes into account. */
-	unsigned bytes = ctx->wbuflen;
-	unsigned pad;
-
-	/* Now count remaining bytes. */
-	ctx->total64 += bytes;
+	unsigned i, pad, in_buf;

	/* Pad the buffer to the next 64-byte boundary with 0x80,0,0,0...
	(FIPS 180-2:5.1.1) */
-	pad = (bytes >= 56 ? 64 + 56 - bytes : 56 - bytes);
-	memset(&ctx->wbuffer[bytes], 0, pad);
-	ctx->wbuffer[bytes] = 0x80;
+	in_buf = ctx->total64 & 63;
+	pad = (in_buf >= 56 ? 64 + 56 - in_buf : 56 - in_buf);
+	memset(&ctx->wbuffer[in_buf], 0, pad);
+	ctx->wbuffer[in_buf] = 0x80;

	/* Put the 64-bit file length in bits at the end of the buffer. */
	{
	uint64_t t = ctx->total64 << 3;
	t = hton64(t);
	/* wbuffer is suitably aligned for this */
-	(uint64_t ) &ctx->wbuffer[bytes + pad] = t;
+	(uint64_t ) &ctx->wbuffer[in_buf + pad] = t;
	}

	/* Process last bytes. */
-	sha256_process_block64(ctx->wbuffer, bytes + pad + 8, ctx);
+	sha256_process_block64(ctx->wbuffer, in_buf + pad + 8, ctx);

-	for (unsigned i = 0; i < 8; ++i)
-	((uint32_t *) resbuf)[i] = ntohl(ctx->H[i]);
+	#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));
	}

-	/* Process the remaining bytes in the internal buffer and the usual
-	prolog according to the standard and write the result to RESBUF.
-
-	IMPORTANT: On some systems it is required that RESBUF is correctly
-	aligned for a 64 bits value. */
	void FAST_FUNC sha512_end(void resbuf, sha512_ctx_t ctx)
	{
-	unsigned bytes = ctx->wbuflen;
-	unsigned pad;
-
-	ctx->total64[0] += bytes;
-	if (ctx->total64[0] < bytes)
-	ctx->total64[1]++;
+	unsigned i, pad, in_buf;

	/* Pad the buffer to the next 128-byte boundary with 0x80,0,0,0...
	(FIPS 180-2:5.1.2) */
-	pad = bytes >= 112 ? 128 + 112 - bytes : 112 - bytes;
-	memset(&ctx->wbuffer[bytes], 0, pad);
-	ctx->wbuffer[bytes] = 0x80;
+	in_buf = ctx->total64[0] & 127;
+	pad = in_buf >= 112 ? 128 + 112 - in_buf : 112 - in_buf;
+	memset(&ctx->wbuffer[in_buf], 0, pad);
+	ctx->wbuffer[in_buf] = 0x80;

-	(uint64_t ) &ctx->wbuffer[bytes + pad + 8] = hton64(ctx->total64[0] << 3);
-	(uint64_t ) &ctx->wbuffer[bytes + pad] = hton64((ctx->total64[1] << 3) \| (ctx->total64[0] >> 61));
+	(uint64_t ) &ctx->wbuffer[in_buf + pad + 8] = hton64(ctx->total64[0] << 3);
+	(uint64_t ) &ctx->wbuffer[in_buf + pad] = hton64((ctx->total64[1] << 3) \| (ctx->total64[0] >> 61));

-	sha512_process_block128(ctx->wbuffer, bytes + pad + 16, ctx);
+	sha512_process_block128(ctx->wbuffer, in_buf + pad + 16, ctx);

-	for (unsigned i = 0; i < 8; ++i)
-	((uint64_t *) resbuf)[i] = hton64(ctx->H[i]);
+	#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));
	}