1 files changed, 130 insertions, 115 deletions

diff --git a/libbb/md5.c b/libbb/md5.c
index d8655ba91..051c8ede4 100644
--- a/libbb/md5.c
+++ b/libbb/md5.c
@@ -1,7 +1,7 @@
 /* vi: set sw=4 ts=4: */
 /*
- * md5.c - Compute MD5 checksum of strings according to the
- *         definition of MD5 in RFC 1321 from April 1992.
+ * Compute MD5 checksum of strings according to the
+ * definition of MD5 in RFC 1321 from April 1992.
  *
  * Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995.
  *
@@ -33,8 +33,7 @@ void FAST_FUNC md5_begin(md5_ctx_t *ctx)
         ctx->B = 0xefcdab89;
         ctx->C = 0x98badcfe;
         ctx->D = 0x10325476;
-        ctx->total = 0;
-        ctx->buflen = 0;
+        ctx->total64 = 0;
 }
 
 /* These are the four functions used in the four steps of the MD5 algorithm
@@ -49,13 +48,14 @@ void FAST_FUNC md5_begin(md5_ctx_t *ctx)
 
 #define rotl32(w, s) (((w) << (s)) | ((w) >> (32 - (s))))
 
-/* Hash a single block, 64 bytes long and 4-byte aligned. */
-static void md5_hash_block(const void *buffer, md5_ctx_t *ctx)
+/* Hash a single block, 64 bytes long and 4-byte aligned */
+static void md5_process_block64(md5_ctx_t *ctx)
 {
-        uint32_t correct_words[16];
-        const uint32_t *words = buffer;
-
 #if MD5_SIZE_VS_SPEED > 0
+        /* Before we start, one word to the strange constants.
+           They are defined in RFC 1321 as
+           T[i] = (int)(4294967296.0 * fabs(sin(i))), i=1..64
+         */
         static const uint32_t C_array[] = {
                 /* round 1 */
                 0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee,
@@ -64,7 +64,7 @@ static void md5_hash_block(const void *buffer, md5_ctx_t *ctx)
                 0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,
                 /* round 2 */
                 0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa,
-                0xd62f105d, 0x2441453, 0xd8a1e681, 0xe7d3fbc8,
+                0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8,
                 0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed,
                 0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,
                 /* round 3 */
@@ -86,40 +86,33 @@ static void md5_hash_block(const void *buffer, md5_ctx_t *ctx)
                 5, 8, 11, 14, 1, 4, 7, 10, 13, 0, 3, 6, 9, 12, 15, 2,   /* 3 */
                 0, 7, 14, 5, 12, 3, 10, 1, 8, 15, 6, 13, 4, 11, 2, 9    /* 4 */
         };
-# if MD5_SIZE_VS_SPEED > 1
-        static const char S_array[] ALIGN1 = {
-                7, 12, 17, 22,
-                5, 9, 14, 20,
-                4, 11, 16, 23,
-                6, 10, 15, 21
-        };
-# endif /* MD5_SIZE_VS_SPEED > 1 */
 #endif
+        uint32_t *words = (void*) ctx->wbuffer;
         uint32_t A = ctx->A;
         uint32_t B = ctx->B;
         uint32_t C = ctx->C;
         uint32_t D = ctx->D;
 
-        /* Process all bytes in the buffer with 64 bytes in each round of
-           the loop.  */
-        uint32_t *cwp = correct_words;
-        uint32_t A_save = A;
-        uint32_t B_save = B;
-        uint32_t C_save = C;
-        uint32_t D_save = D;
+#if MD5_SIZE_VS_SPEED >= 2  /* 2 or 3 */
 
-#if MD5_SIZE_VS_SPEED > 1
+        static const char S_array[] ALIGN1 = {
+                7, 12, 17, 22,
+                5, 9, 14, 20,
+                4, 11, 16, 23,
+                6, 10, 15, 21
+        };
         const uint32_t *pc;
         const char *pp;
         const char *ps;
         int i;
         uint32_t temp;
 
+# if BB_BIG_ENDIAN
         for (i = 0; i < 16; i++)
-                cwp[i] = SWAP_LE32(words[i]);
-        words += 16;
+                words[i] = SWAP_LE32(words[i]);
+# endif
 
-# if MD5_SIZE_VS_SPEED > 2
+# if MD5_SIZE_VS_SPEED == 3
         pc = C_array;
         pp = P_array;
         ps = S_array - 4;
@@ -141,7 +134,7 @@ static void md5_hash_block(const void *buffer, md5_ctx_t *ctx)
                 case 3:
                         temp += FI(B, C, D);
                 }
-                temp += cwp[(int) (*pp++)] + *pc++;
+                temp += words[(int) (*pp++)] + *pc++;
                 temp = rotl32(temp, ps[i & 3]);
                 temp += B;
                 A = D;
@@ -149,13 +142,13 @@ static void md5_hash_block(const void *buffer, md5_ctx_t *ctx)
                 C = B;
                 B = temp;
         }
-# else
+# else  /* MD5_SIZE_VS_SPEED == 2 */
         pc = C_array;
         pp = P_array;
         ps = S_array;
 
         for (i = 0; i < 16; i++) {
-                temp = A + FF(B, C, D) + cwp[(int) (*pp++)] + *pc++;
+                temp = A + FF(B, C, D) + words[(int) (*pp++)] + *pc++;
                 temp = rotl32(temp, ps[i & 3]);
                 temp += B;
                 A = D;
@@ -165,7 +158,7 @@ static void md5_hash_block(const void *buffer, md5_ctx_t *ctx)
         }
         ps += 4;
         for (i = 0; i < 16; i++) {
-                temp = A + FG(B, C, D) + cwp[(int) (*pp++)] + *pc++;
+                temp = A + FG(B, C, D) + words[(int) (*pp++)] + *pc++;
                 temp = rotl32(temp, ps[i & 3]);
                 temp += B;
                 A = D;
@@ -175,7 +168,7 @@ static void md5_hash_block(const void *buffer, md5_ctx_t *ctx)
         }
         ps += 4;
         for (i = 0; i < 16; i++) {
-                temp = A + FH(B, C, D) + cwp[(int) (*pp++)] + *pc++;
+                temp = A + FH(B, C, D) + words[(int) (*pp++)] + *pc++;
                 temp = rotl32(temp, ps[i & 3]);
                 temp += B;
                 A = D;
@@ -185,7 +178,7 @@ static void md5_hash_block(const void *buffer, md5_ctx_t *ctx)
         }
         ps += 4;
         for (i = 0; i < 16; i++) {
-                temp = A + FI(B, C, D) + cwp[(int) (*pp++)] + *pc++;
+                temp = A + FI(B, C, D) + words[(int) (*pp++)] + *pc++;
                 temp = rotl32(temp, ps[i & 3]);
                 temp += B;
                 A = D;
@@ -193,35 +186,41 @@ static void md5_hash_block(const void *buffer, md5_ctx_t *ctx)
                 C = B;
                 B = temp;
         }
+# endif
+        /* Add checksum to the starting values */
+        ctx->A += A;
+        ctx->B += B;
+        ctx->C += C;
+        ctx->D += D;
+
+#else  /* MD5_SIZE_VS_SPEED == 0 or 1 */
+
+        uint32_t A_save = A;
+        uint32_t B_save = B;
+        uint32_t C_save = C;
+        uint32_t D_save = D;
+# if MD5_SIZE_VS_SPEED == 1
+        const uint32_t *pc;
+        const char *pp;
+        int i;
+# endif
 
-# endif /* MD5_SIZE_VS_SPEED > 2 */
-#else
         /* First round: using the given function, the context and a constant
-           the next context is computed.  Because the algorithms processing
+           the next context is computed.  Because the algorithm's processing
            unit is a 32-bit word and it is determined to work on words in
            little endian byte order we perhaps have to change the byte order
            before the computation.  To reduce the work for the next steps
-           we store the swapped words in the array CORRECT_WORDS.  */
+           we save swapped words in WORDS array.  */
+# undef OP
 # define OP(a, b, c, d, s, T) \
         do { \
-                a += FF(b, c, d) + (*cwp++ = SWAP_LE32(*words)) + T; \
-                ++words; \
+                a += FF(b, c, d) + (*words IF_BIG_ENDIAN(= SWAP_LE32(*words))) + T; \
+                words++; \
                 a = rotl32(a, s); \
                 a += b; \
         } while (0)
 
-        /* Before we start, one word to the strange constants.
-           They are defined in RFC 1321 as
-           T[i] = (int)(4294967296.0 * fabs(sin(i))), i=1..64
-         */
-
-# if MD5_SIZE_VS_SPEED == 1
-        const uint32_t *pc;
-        const char *pp;
-        int i;
-# endif /* MD5_SIZE_VS_SPEED */
-
-        /* Round 1.  */
+        /* Round 1 */
 # if MD5_SIZE_VS_SPEED == 1
         pc = C_array;
         for (i = 0; i < 4; i++) {
@@ -247,20 +246,21 @@ static void md5_hash_block(const void *buffer, md5_ctx_t *ctx)
         OP(D, A, B, C, 12, 0xfd987193);
         OP(C, D, A, B, 17, 0xa679438e);
         OP(B, C, D, A, 22, 0x49b40821);
-# endif /* MD5_SIZE_VS_SPEED == 1 */
+# endif
+        words -= 16;
 
         /* For the second to fourth round we have the possibly swapped words
-           in CORRECT_WORDS.  Redefine the macro to take an additional first
+           in WORDS.  Redefine the macro to take an additional first
            argument specifying the function to use.  */
 # undef OP
 # define OP(f, a, b, c, d, k, s, T) \
         do { \
-                a += f(b, c, d) + correct_words[k] + T; \
+                a += f(b, c, d) + words[k] + T; \
                 a = rotl32(a, s); \
                 a += b; \
         } while (0)
 
-        /* Round 2.  */
+        /* Round 2 */
 # if MD5_SIZE_VS_SPEED == 1
         pp = P_array;
         for (i = 0; i < 4; i++) {
@@ -286,9 +286,9 @@ static void md5_hash_block(const void *buffer, md5_ctx_t *ctx)
         OP(FG, D, A, B, C, 2, 9, 0xfcefa3f8);
         OP(FG, C, D, A, B, 7, 14, 0x676f02d9);
         OP(FG, B, C, D, A, 12, 20, 0x8d2a4c8a);
-# endif /* MD5_SIZE_VS_SPEED == 1 */
+# endif
 
-        /* Round 3.  */
+        /* Round 3 */
 # if MD5_SIZE_VS_SPEED == 1
         for (i = 0; i < 4; i++) {
                 OP(FH, A, B, C, D, (int) (*pp++), 4, *pc++);
@@ -313,9 +313,9 @@ static void md5_hash_block(const void *buffer, md5_ctx_t *ctx)
         OP(FH, D, A, B, C, 12, 11, 0xe6db99e5);
         OP(FH, C, D, A, B, 15, 16, 0x1fa27cf8);
         OP(FH, B, C, D, A, 2, 23, 0xc4ac5665);
-# endif /* MD5_SIZE_VS_SPEED == 1 */
+# endif
 
-        /* Round 4.  */
+        /* Round 4 */
 # if MD5_SIZE_VS_SPEED == 1
         for (i = 0; i < 4; i++) {
                 OP(FI, A, B, C, D, (int) (*pp++), 6, *pc++);
@@ -340,52 +340,62 @@ static void md5_hash_block(const void *buffer, md5_ctx_t *ctx)
         OP(FI, D, A, B, C, 11, 10, 0xbd3af235);
         OP(FI, C, D, A, B, 2, 15, 0x2ad7d2bb);
         OP(FI, B, C, D, A, 9, 21, 0xeb86d391);
-# endif /* MD5_SIZE_VS_SPEED == 1 */
-#endif  /* MD5_SIZE_VS_SPEED > 1 */
-
-        /* Add the starting values of the context.  */
-        A += A_save;
-        B += B_save;
-        C += C_save;
-        D += D_save;
-
-        /* Put checksum in context given as argument.  */
-        ctx->A = A;
-        ctx->B = B;
-        ctx->C = C;
-        ctx->D = D;
+# endif
+        /* Add checksum to the starting values */
+        ctx->A = A_save + A;
+        ctx->B = B_save + B;
+        ctx->C = C_save + C;
+        ctx->D = D_save + D;
+#endif
 }
 
 /* Feed data through a temporary buffer to call md5_hash_aligned_block()
  * with chunks of data that are 4-byte aligned and a multiple of 64 bytes.
  * This function's internal buffer remembers previous data until it has 64
  * bytes worth to pass on.  Call md5_end() to flush this buffer. */
-void FAST_FUNC md5_hash(const void *buffer, size_t len, md5_ctx_t *ctx)
+void FAST_FUNC md5_hash(md5_ctx_t *ctx, const void *buffer, size_t len)
 {
-        char *buf = (char *)buffer;
+        unsigned bufpos = ctx->total64 & 63;
+        unsigned remaining;
 
-        /* RFC 1321 specifies the possible length of the file up to 2^64 bits,
+        /* RFC 1321 specifies the possible length of the file up to 2^64 bits.
          * Here we only track the number of bytes.  */
-        ctx->total += len;
-
-        /* Process all input. */
-        while (len) {
-                unsigned i = 64 - ctx->buflen;
-
-                /* Copy data into aligned buffer. */
-                if (i > len)
-                        i = len;
-                memcpy(ctx->buffer + ctx->buflen, buf, i);
-                len -= i;
-                ctx->buflen += i;
-                buf += i;
+        ctx->total64 += len;
+#if 0
+        remaining = 64 - bufpos;
+
+        /* Hash whole blocks */
+        while (len >= remaining) {
+                memcpy(ctx->wbuffer + bufpos, buffer, remaining);
+                buffer = (const char *)buffer + remaining;
+                len -= remaining;
+                remaining = 64;
+                bufpos = 0;
+                md5_process_block64(ctx);
+        }
 
-                /* When buffer fills up, process it. */
-                if (ctx->buflen == 64) {
-                        md5_hash_block(ctx->buffer, ctx);
-                        ctx->buflen = 0;
-                }
+        /* Save last, partial blosk */
+        memcpy(ctx->wbuffer + bufpos, buffer, len);
+#else
+        /* Tiny bit smaller code */
+        while (1) {
+                remaining = 64 - bufpos;
+                if (remaining > len)
+                        remaining = len;
+                /* Copy data into aligned buffer */
+                memcpy(ctx->wbuffer + bufpos, buffer, remaining);
+                len -= remaining;
+                buffer = (const char *)buffer + remaining;
+                bufpos += remaining;
+                /* clever way to do "if (bufpos != 64) break; ... ; bufpos = 0;" */
+                bufpos -= 64;
+                if (bufpos != 0)
+                        break;
+                /* Buffer is filled up, process it */
+                md5_process_block64(ctx);
+                /*bufpos = 0; - already is */
         }
+#endif
 }
 
 /* Process the remaining bytes in the buffer and put result from CTX
@@ -393,26 +403,31 @@ void FAST_FUNC md5_hash(const void *buffer, size_t len, md5_ctx_t *ctx)
  * endian byte order, so that a byte-wise output yields to the wanted
  * ASCII representation of the message digest.
  */
-void FAST_FUNC md5_end(void *resbuf, md5_ctx_t *ctx)
+void FAST_FUNC md5_end(md5_ctx_t *ctx, void *resbuf)
 {
-        char *buf = ctx->buffer;
-        int i;
-
-        /* Pad data to block size.  */
-        buf[ctx->buflen++] = 0x80;
-        memset(buf + ctx->buflen, 0, 128 - ctx->buflen);
-
-        /* Put the 64-bit file length in *bits* at the end of the buffer.  */
-        ctx->total <<= 3;
-        if (ctx->buflen > 56)
-                buf += 64;
-        for (i = 0; i < 8; i++)
-                buf[56 + i] = ctx->total >> (i*8);
-
-        /* Process last bytes.  */
-        if (buf != ctx->buffer)
-                md5_hash_block(ctx->buffer, ctx);
-        md5_hash_block(buf, ctx);
+        unsigned bufpos = ctx->total64 & 63;
+        /* Pad the buffer to the next 64-byte boundary with 0x80,0,0,0... */
+        ctx->wbuffer[bufpos++] = 0x80;
+
+        /* This loop iterates either once or twice, no more, no less */
+        while (1) {
+                unsigned remaining = 64 - bufpos;
+                memset(ctx->wbuffer + bufpos, 0, remaining);
+                /* Do we have enough space for the length count? */
+                if (remaining >= 8) {
+                        /* Store the 64-bit counter of bits in the buffer in BE format */
+                        uint64_t t = ctx->total64 << 3;
+                        unsigned i;
+                        for (i = 0; i < 8; i++) {
+                                ctx->wbuffer[56 + i] = t;
+                                t >>= 8;
+                        }
+                }
+                md5_process_block64(ctx);
+                if (remaining >= 8)
+                        break;
+                bufpos = 0;
+        }
 
         /* The MD5 result is in little endian byte order.
          * We (ab)use the fact that A-D are consecutive in memory.