From cd2cd312b70e53b2095827d84c675b85cef4d2f6 Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Thu, 12 Mar 2009 15:40:27 +0000 Subject: shrink sha hashing a bit more (remove wbuflen field from ctx), remove the requirement for aligned buffer function old new delta sha512_hash 262 297 +35 sha1_end 136 143 +7 passwd_main 1019 1023 +4 sha256_end 135 137 +2 count_lines 72 74 +2 sha256_hash 259 260 +1 popstring 164 158 -6 sha512_begin 88 81 -7 sha256_begin 44 37 -7 parse_expr 832 824 -8 bbunpack 446 438 -8 sha256_process_block64 529 520 -9 md5_end 166 151 -15 evaltreenr 817 802 -15 evaltree 817 802 -15 sha512_end 204 182 -22 sha512_process_block128 1444 1405 -39 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 6/11 up/down: 51/-151) Total: -100 bytes --- libbb/md5.c | 19 +++-- libbb/sha1.c | 224 +++++++++++++++++++++++++++-------------------------------- 2 files changed, 111 insertions(+), 132 deletions(-) (limited to 'libbb') diff --git a/libbb/md5.c b/libbb/md5.c index eb15d75..768dfbc 100644 --- a/libbb/md5.c +++ b/libbb/md5.c @@ -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); } diff --git a/libbb/sha1.c b/libbb/sha1.c index 38be575..1584e98 100644 --- a/libbb/sha1.c +++ b/libbb/sha1.c @@ -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)); } -- cgit v1.1