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

diff --git a/include/libbb.h b/include/libbb.h
index 4c99010..3f566f8 100644 (file)
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -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[64*2]; /* 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[128*2]; /* NB: always correctly aligned for uint64_t */
 } sha512_ctx_t;
 void sha512_begin(sha512_ctx_t *ctx) FAST_FUNC;

diff --git a/libbb/md5.c b/libbb/md5.c
index eb15d75..768dfbc 100644 (file)
--- 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 (file)
--- 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));
 }