sha: merge sha1/sha256 handling (they are similar enough for this),

 shrink sha215 code

function                                             old     new   delta
sha1_end                                             129     142     +13
sha1_process_block64                                 486     494      +8
sha256_begin                                          37      44      +7
sha1_begin                                            49      56      +7
sha1_hash                                            108     112      +4
...
sha512_end                                           204     184     -20
sha512_process_block128                             1405    1334     -71
sha256_process_block64                               520     446     -74
sha256_end                                           147       -    -147
sha512_hash                                          297     130    -167
sha256_hash                                          260       -    -260
------------------------------------------------------------------------------
(add/remove: 0/2 grow/shrink: 11/9 up/down: 59/-752)         Total: -693 bytes

2 files changed, 94 insertions, 211 deletions

diff --git a/include/libbb.h b/include/libbb.h
index b04488a54..b6eab6f24 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -1321,24 +1321,21 @@ extern const char bb_uuenc_tbl_std[];
 void bb_uuencode(char *store, const void *s, int length, const char *tbl) FAST_FUNC;
 
 typedef struct sha1_ctx_t {
+        uint32_t hash[8];    /* 5, +3 elements for sha256 */
         uint64_t total64;
         uint8_t wbuffer[64]; /* NB: always correctly aligned for uint64_t */
-        uint32_t hash[5];
+        void (*process_block)(struct sha1_ctx_t*);
 } sha1_ctx_t;
 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 {
-        uint64_t total64;
-        uint32_t hash[8];
-        uint8_t wbuffer[64]; /* NB: always correctly aligned for uint64_t */
-} sha256_ctx_t;
+typedef struct sha1_ctx_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;
+#define sha256_hash sha1_hash
+#define sha256_end sha1_end
 typedef struct sha512_ctx_t {
-        uint64_t total64[2];
         uint64_t hash[8];
+        uint64_t total64[2];
         uint8_t wbuffer[128]; /* NB: always correctly aligned for uint64_t */
 } sha512_ctx_t;
 void sha512_begin(sha512_ctx_t *ctx) FAST_FUNC;
diff --git a/libbb/sha1.c b/libbb/sha1.c
index efdb0f58e..8ecf71a9d 100644
--- a/libbb/sha1.c
+++ b/libbb/sha1.c
@@ -203,9 +203,10 @@ static const uint32_t K512_lo[80] = {
 
 /* 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)
+static void sha256_process_block64(sha256_ctx_t *ctx)
 {
-        const uint32_t *words = buffer;
+        unsigned t;
+        uint32_t W[64];
         uint32_t a = ctx->hash[0];
         uint32_t b = ctx->hash[1];
         uint32_t c = ctx->hash[2];
@@ -214,15 +215,9 @@ static void sha256_process_block64(const void *buffer, size_t len, sha256_ctx_t
         uint32_t f = ctx->hash[5];
         uint32_t g = ctx->hash[6];
         uint32_t h = ctx->hash[7];
+        const uint32_t *words = (uint32_t*) ctx->wbuffer;
 
-        /* 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.  */
+        /* 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))
@@ -230,54 +225,51 @@ static void sha256_process_block64(const void *buffer, size_t len, sha256_ctx_t
 #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++;
-                }
+        /* 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;
-                }
+        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--;
-        }
+        /* Add the starting values of the context according to FIPS 180-2:6.2.2
+           step 4.  */
+        ctx->hash[0] += a;
+        ctx->hash[1] += b;
+        ctx->hash[2] += c;
+        ctx->hash[3] += d;
+        ctx->hash[4] += e;
+        ctx->hash[5] += f;
+        ctx->hash[6] += g;
+        ctx->hash[7] += h;
 }
 /* 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)
+static void sha512_process_block128(sha512_ctx_t *ctx)
 {
-        const uint64_t *words = buffer;
+        unsigned t;
+        uint64_t W[80];
         uint64_t a = ctx->hash[0];
         uint64_t b = ctx->hash[1];
         uint64_t c = ctx->hash[2];
@@ -286,13 +278,9 @@ static void sha512_process_block128(const void *buffer, size_t len, sha512_ctx_t
         uint64_t f = ctx->hash[5];
         uint64_t g = ctx->hash[6];
         uint64_t h = ctx->hash[7];
+        const uint32_t *words = (uint32_t*) ctx->wbuffer;
 
-        len /= (sizeof(uint64_t) * 16);
-        while (len) {
-                unsigned t;
-                uint64_t W[80];
-
-                /* Operators defined in FIPS 180-2:4.1.2.  */
+        /* 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))
@@ -300,58 +288,56 @@ static void sha512_process_block128(const void *buffer, size_t len, sha512_ctx_t
 #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;
-                }
+        /* 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--;
-        }
+        /* Add the starting values of the context according to FIPS 180-2:6.3.2
+           step 4.  */
+        ctx->hash[0] += a;
+        ctx->hash[1] += b;
+        ctx->hash[2] += c;
+        ctx->hash[3] += d;
+        ctx->hash[4] += e;
+        ctx->hash[5] += f;
+        ctx->hash[6] += g;
+        ctx->hash[7] += h;
 }
 
 
 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;
+        ctx->total64 = 0;
+        ctx->process_block = sha1_process_block64;
 }
 
 static const uint32_t init256[] = {
@@ -380,6 +366,7 @@ void FAST_FUNC sha256_begin(sha256_ctx_t *ctx)
 {
         memcpy(ctx->hash, init256, sizeof(init256));
         ctx->total64 = 0;
+        ctx->process_block = sha256_process_block64;
 }
 /* Initialize structure containing state of computation.
    (FIPS 180-2:5.3.3)  */
@@ -405,64 +392,16 @@ void FAST_FUNC sha1_hash(const void *buffer, size_t len, sha1_ctx_t *ctx)
                 len -= add;
                 add = SHA1_BLOCK_SIZE;
                 in_buf = 0;
-                sha1_process_block64(ctx);
+                ctx->process_block(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;
+        unsigned add = 128 - in_buf;
 
         /* First increment the byte count.  FIPS 180-2 specifies the possible
            length of the file up to 2^128 _bits_.
@@ -471,39 +410,16 @@ void FAST_FUNC sha512_hash(const void *buffer, size_t len, sha512_ctx_t *ctx)
         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;
+        while (len >= add) {    /* transfer whole blocks while possible  */
                 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;
+                add = 128;
+                in_buf = 0;
+                sha512_process_block128(ctx);
         }
 
-        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);
+        memcpy(ctx->wbuffer + in_buf, buffer, len);
 }
 
 
@@ -528,48 +444,18 @@ void FAST_FUNC sha1_end(void *resbuf, sha1_ctx_t *ctx)
                         /* wbuffer is suitably aligned for this */
                         *(uint64_t *) (&ctx->wbuffer[SHA1_BLOCK_SIZE - 8]) = t;
                 }
-                sha1_process_block64(ctx);
+                ctx->process_block(ctx);
                 if (pad >= 8)
                         break;
         }
 
+        in_buf = (ctx->process_block == sha1_process_block64) ? 5 : 8;
         /* 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)
+        for (i = 0; i < in_buf; ++i)
                 ctx->hash[i] = htonl(ctx->hash[i]);
 #endif
-        memcpy(resbuf, ctx->hash, sizeof(ctx->hash));
+        memcpy(resbuf, ctx->hash, sizeof(ctx->hash[0]) * in_buf);
 }
 
 void FAST_FUNC sha512_end(void *resbuf, sha512_ctx_t *ctx)
@@ -596,7 +482,7 @@ void FAST_FUNC sha512_end(void *resbuf, sha512_ctx_t *ctx)
                         t = hton64(t);
                         *(uint64_t *) (&ctx->wbuffer[128 - 16]) = t;
                 }
-                sha512_process_block128(ctx->wbuffer, 128, ctx);
+                sha512_process_block128(ctx);
                 if (pad >= 16)
                         break;
         }