crypto: Add scrypt N=1024 PoW

Add scrypt pow hashing algorithm as a proof of work function.
Rebased from litecoin-project/litecoin@02961f0 minus strencodings.h macros.

5 files changed, 255 insertions, 12 deletions

diff --git a/src/crypto/scrypt-sse2.cpp b/src/crypto/scrypt-sse2.cpp
index 04b60e3ef..c4f26aa30 100644
--- a/src/crypto/scrypt-sse2.cpp
+++ b/src/crypto/scrypt-sse2.cpp
@@ -34,7 +34,6 @@
 #include <stdlib.h>
 #include <stdint.h>
 #include <string.h>
-#include <openssl/sha.h>
 
 #include <emmintrin.h>
 
diff --git a/src/crypto/scrypt.cpp b/src/crypto/scrypt.cpp
index b96ee038b..3bdd9d6cb 100644
--- a/src/crypto/scrypt.cpp
+++ b/src/crypto/scrypt.cpp
@@ -32,7 +32,6 @@
 #include <stdlib.h>
 #include <stdint.h>
 #include <string.h>
-#include <openssl/sha.h>
 
 #if defined(USE_SSE2) && !defined(USE_SSE2_ALWAYS)
 #ifdef _MSC_VER
@@ -61,6 +60,242 @@ static inline void be32enc(void *pp, uint32_t x)
 }
 
 #endif
+
+typedef struct SHA256_CTXContext {
+    uint32_t total[2];
+    uint32_t state[8];
+    uint8_t buffer[64];
+} SHA256_CTX;
+
+#define GET_UINT32(n, b, i)                  \
+    {                                        \
+        (n) = ((uint32_t)(b)[(i)] << 24)     \
+            | ((uint32_t)(b)[(i) + 1] << 16) \
+            | ((uint32_t)(b)[(i) + 2] << 8)  \
+            | ((uint32_t)(b)[(i) + 3]);      \
+    }
+
+#define PUT_UINT32(n, b, i)                  \
+    {                                        \
+        (b)[(i)] = (uint8_t)((n) >> 24);     \
+        (b)[(i) + 1] = (uint8_t)((n) >> 16); \
+        (b)[(i) + 2] = (uint8_t)((n) >> 8);  \
+        (b)[(i) + 3] = (uint8_t)((n));       \
+    }
+
+#define SHR(x, n) ((x & 0xFFFFFFFF) >> n)
+#define ROTR(x, n) (SHR(x, n) | (x << (32 - n)))
+#define S0(x) (ROTR(x, 7) ^ ROTR(x, 18) ^ SHR(x, 3))
+#define S1(x) (ROTR(x, 17) ^ ROTR(x, 19) ^ SHR(x, 10))
+#define S2(x) (ROTR(x, 2) ^ ROTR(x, 13) ^ ROTR(x, 22))
+#define S3(x) (ROTR(x, 6) ^ ROTR(x, 11) ^ ROTR(x, 25))
+#define F0(x, y, z) ((x & y) | (z & (x | y)))
+#define F1(x, y, z) (z ^ (x & (y ^ z)))
+#define R(t) (W[t] = S1(W[t - 2]) + W[t - 7] + S0(W[t - 15]) + W[t - 16])
+
+#define P(a, b, c, d, e, f, g, h, x, K)          \
+    {                                            \
+        temp1 = h + S3(e) + F1(e, f, g) + K + x; \
+        temp2 = S2(a) + F0(a, b, c);             \
+        d += temp1;                              \
+        h = temp1 + temp2;                       \
+    }
+
+static void
+SHA256_Init(SHA256_CTX* ctx)
+{
+    ctx->total[0] = 0;
+    ctx->total[1] = 0;
+
+    ctx->state[0] = 0x6A09E667;
+    ctx->state[1] = 0xBB67AE85;
+    ctx->state[2] = 0x3C6EF372;
+    ctx->state[3] = 0xA54FF53A;
+    ctx->state[4] = 0x510E527F;
+    ctx->state[5] = 0x9B05688C;
+    ctx->state[6] = 0x1F83D9AB;
+    ctx->state[7] = 0x5BE0CD19;
+}
+
+static void
+SHA256_Process(SHA256_CTX* ctx, uint8_t data[64])
+{
+    uint32_t temp1, temp2, W[64];
+    uint32_t A, B, C, D, E, F, G, H;
+
+    GET_UINT32(W[0], data, 0);
+    GET_UINT32(W[1], data, 4);
+    GET_UINT32(W[2], data, 8);
+    GET_UINT32(W[3], data, 12);
+    GET_UINT32(W[4], data, 16);
+    GET_UINT32(W[5], data, 20);
+    GET_UINT32(W[6], data, 24);
+    GET_UINT32(W[7], data, 28);
+    GET_UINT32(W[8], data, 32);
+    GET_UINT32(W[9], data, 36);
+    GET_UINT32(W[10], data, 40);
+    GET_UINT32(W[11], data, 44);
+    GET_UINT32(W[12], data, 48);
+    GET_UINT32(W[13], data, 52);
+    GET_UINT32(W[14], data, 56);
+    GET_UINT32(W[15], data, 60);
+
+    A = ctx->state[0];
+    B = ctx->state[1];
+    C = ctx->state[2];
+    D = ctx->state[3];
+    E = ctx->state[4];
+    F = ctx->state[5];
+    G = ctx->state[6];
+    H = ctx->state[7];
+
+    P(A, B, C, D, E, F, G, H, W[0], 0x428A2F98);
+    P(H, A, B, C, D, E, F, G, W[1], 0x71374491);
+    P(G, H, A, B, C, D, E, F, W[2], 0xB5C0FBCF);
+    P(F, G, H, A, B, C, D, E, W[3], 0xE9B5DBA5);
+    P(E, F, G, H, A, B, C, D, W[4], 0x3956C25B);
+    P(D, E, F, G, H, A, B, C, W[5], 0x59F111F1);
+    P(C, D, E, F, G, H, A, B, W[6], 0x923F82A4);
+    P(B, C, D, E, F, G, H, A, W[7], 0xAB1C5ED5);
+    P(A, B, C, D, E, F, G, H, W[8], 0xD807AA98);
+    P(H, A, B, C, D, E, F, G, W[9], 0x12835B01);
+    P(G, H, A, B, C, D, E, F, W[10], 0x243185BE);
+    P(F, G, H, A, B, C, D, E, W[11], 0x550C7DC3);
+    P(E, F, G, H, A, B, C, D, W[12], 0x72BE5D74);
+    P(D, E, F, G, H, A, B, C, W[13], 0x80DEB1FE);
+    P(C, D, E, F, G, H, A, B, W[14], 0x9BDC06A7);
+    P(B, C, D, E, F, G, H, A, W[15], 0xC19BF174);
+    P(A, B, C, D, E, F, G, H, R(16), 0xE49B69C1);
+    P(H, A, B, C, D, E, F, G, R(17), 0xEFBE4786);
+    P(G, H, A, B, C, D, E, F, R(18), 0x0FC19DC6);
+    P(F, G, H, A, B, C, D, E, R(19), 0x240CA1CC);
+    P(E, F, G, H, A, B, C, D, R(20), 0x2DE92C6F);
+    P(D, E, F, G, H, A, B, C, R(21), 0x4A7484AA);
+    P(C, D, E, F, G, H, A, B, R(22), 0x5CB0A9DC);
+    P(B, C, D, E, F, G, H, A, R(23), 0x76F988DA);
+    P(A, B, C, D, E, F, G, H, R(24), 0x983E5152);
+    P(H, A, B, C, D, E, F, G, R(25), 0xA831C66D);
+    P(G, H, A, B, C, D, E, F, R(26), 0xB00327C8);
+    P(F, G, H, A, B, C, D, E, R(27), 0xBF597FC7);
+    P(E, F, G, H, A, B, C, D, R(28), 0xC6E00BF3);
+    P(D, E, F, G, H, A, B, C, R(29), 0xD5A79147);
+    P(C, D, E, F, G, H, A, B, R(30), 0x06CA6351);
+    P(B, C, D, E, F, G, H, A, R(31), 0x14292967);
+    P(A, B, C, D, E, F, G, H, R(32), 0x27B70A85);
+    P(H, A, B, C, D, E, F, G, R(33), 0x2E1B2138);
+    P(G, H, A, B, C, D, E, F, R(34), 0x4D2C6DFC);
+    P(F, G, H, A, B, C, D, E, R(35), 0x53380D13);
+    P(E, F, G, H, A, B, C, D, R(36), 0x650A7354);
+    P(D, E, F, G, H, A, B, C, R(37), 0x766A0ABB);
+    P(C, D, E, F, G, H, A, B, R(38), 0x81C2C92E);
+    P(B, C, D, E, F, G, H, A, R(39), 0x92722C85);
+    P(A, B, C, D, E, F, G, H, R(40), 0xA2BFE8A1);
+    P(H, A, B, C, D, E, F, G, R(41), 0xA81A664B);
+    P(G, H, A, B, C, D, E, F, R(42), 0xC24B8B70);
+    P(F, G, H, A, B, C, D, E, R(43), 0xC76C51A3);
+    P(E, F, G, H, A, B, C, D, R(44), 0xD192E819);
+    P(D, E, F, G, H, A, B, C, R(45), 0xD6990624);
+    P(C, D, E, F, G, H, A, B, R(46), 0xF40E3585);
+    P(B, C, D, E, F, G, H, A, R(47), 0x106AA070);
+    P(A, B, C, D, E, F, G, H, R(48), 0x19A4C116);
+    P(H, A, B, C, D, E, F, G, R(49), 0x1E376C08);
+    P(G, H, A, B, C, D, E, F, R(50), 0x2748774C);
+    P(F, G, H, A, B, C, D, E, R(51), 0x34B0BCB5);
+    P(E, F, G, H, A, B, C, D, R(52), 0x391C0CB3);
+    P(D, E, F, G, H, A, B, C, R(53), 0x4ED8AA4A);
+    P(C, D, E, F, G, H, A, B, R(54), 0x5B9CCA4F);
+    P(B, C, D, E, F, G, H, A, R(55), 0x682E6FF3);
+    P(A, B, C, D, E, F, G, H, R(56), 0x748F82EE);
+    P(H, A, B, C, D, E, F, G, R(57), 0x78A5636F);
+    P(G, H, A, B, C, D, E, F, R(58), 0x84C87814);
+    P(F, G, H, A, B, C, D, E, R(59), 0x8CC70208);
+    P(E, F, G, H, A, B, C, D, R(60), 0x90BEFFFA);
+    P(D, E, F, G, H, A, B, C, R(61), 0xA4506CEB);
+    P(C, D, E, F, G, H, A, B, R(62), 0xBEF9A3F7);
+    P(B, C, D, E, F, G, H, A, R(63), 0xC67178F2);
+
+    ctx->state[0] += A;
+    ctx->state[1] += B;
+    ctx->state[2] += C;
+    ctx->state[3] += D;
+    ctx->state[4] += E;
+    ctx->state[5] += F;
+    ctx->state[6] += G;
+    ctx->state[7] += H;
+}
+
+static void
+SHA256_Update(SHA256_CTX* ctx, uint8_t* input, uint32_t length)
+{
+    uint32_t left, fill;
+
+    if (!length)
+        return;
+
+    left = ctx->total[0] & 0x3F;
+    fill = 64 - left;
+
+    ctx->total[0] += length;
+    ctx->total[0] &= 0xFFFFFFFF;
+
+    if (ctx->total[0] < length)
+        ctx->total[1]++;
+
+    if (left && length >= fill) {
+        memcpy((void*)(ctx->buffer + left),
+            (void*)input, fill);
+        SHA256_Process(ctx, ctx->buffer);
+        length -= fill;
+        input += fill;
+        left = 0;
+    }
+
+    while (length >= 64) {
+        SHA256_Process(ctx, input);
+        length -= 64;
+        input += 64;
+    }
+
+    if (length) {
+        memcpy((void*)(ctx->buffer + left),
+            (void*)input, length);
+    }
+}
+
+static void
+SHA256_Final(SHA256_CTX* ctx, uint8_t digest[32])
+{
+    uint32_t last, padn;
+    uint32_t high, low;
+    uint8_t msglen[8];
+
+    high = (ctx->total[0] >> 29)
+        | (ctx->total[1] << 3);
+    low = (ctx->total[0] << 3);
+
+    PUT_UINT32(high, msglen, 0);
+    PUT_UINT32(low, msglen, 4);
+
+    last = ctx->total[0] & 0x3F;
+    padn = (last < 56) ? (56 - last) : (120 - last);
+
+    uint8_t sha256_padding[64];
+    memset(sha256_padding, 0, 64);
+    memset(sha256_padding, 0x80, 1);
+
+    SHA256_Update(ctx, sha256_padding, padn);
+    SHA256_Update(ctx, msglen, 8);
+
+    PUT_UINT32(ctx->state[0], digest, 0);
+    PUT_UINT32(ctx->state[1], digest, 4);
+    PUT_UINT32(ctx->state[2], digest, 8);
+    PUT_UINT32(ctx->state[3], digest, 12);
+    PUT_UINT32(ctx->state[4], digest, 16);
+    PUT_UINT32(ctx->state[5], digest, 20);
+    PUT_UINT32(ctx->state[6], digest, 24);
+    PUT_UINT32(ctx->state[7], digest, 28);
+}
+
 typedef struct HMAC_SHA256Context {
 	SHA256_CTX ictx;
 	SHA256_CTX octx;
@@ -78,8 +313,8 @@ HMAC_SHA256_Init(HMAC_SHA256_CTX *ctx, const void *_K, size_t Klen)
 	/* If Klen > 64, the key is really SHA256(K). */
 	if (Klen > 64) {
 		SHA256_Init(&ctx->ictx);
-		SHA256_Update(&ctx->ictx, K, Klen);
-		SHA256_Final(khash, &ctx->ictx);
+		SHA256_Update(&ctx->ictx, (uint8_t*)K, Klen);
+		SHA256_Final(&ctx->ictx, (uint8_t*)khash);
 		K = khash;
 		Klen = 32;
 	}
@@ -107,7 +342,7 @@ static void
 HMAC_SHA256_Update(HMAC_SHA256_CTX *ctx, const void *in, size_t len)
 {
 	/* Feed data to the inner SHA256 operation. */
-	SHA256_Update(&ctx->ictx, in, len);
+	SHA256_Update(&ctx->ictx, (uint8_t*)in, len);
 }
 
 /* Finish an HMAC-SHA256 operation. */
@@ -117,13 +352,13 @@ HMAC_SHA256_Final(unsigned char digest[32], HMAC_SHA256_CTX *ctx)
 	unsigned char ihash[32];
 
 	/* Finish the inner SHA256 operation. */
-	SHA256_Final(ihash, &ctx->ictx);
+	SHA256_Final(&ctx->ictx, ihash);
 
 	/* Feed the inner hash to the outer SHA256 operation. */
 	SHA256_Update(&ctx->octx, ihash, 32);
 
 	/* Finish the outer SHA256 operation. */
-	SHA256_Final(digest, &ctx->octx);
+	SHA256_Final(&ctx->octx, digest);
 
 	/* Clean the stack. */
 	memset(ihash, 0, 32);
@@ -327,6 +562,15 @@ std::string scrypt_detect_sse2()
 
 void scrypt_1024_1_1_256(const char *input, char *output)
 {
-	char scratchpad[SCRYPT_SCRATCHPAD_SIZE];
+    char scratchpad[SCRYPT_SCRATCHPAD_SIZE];
     scrypt_1024_1_1_256_sp(input, output, scratchpad);
 }
+
+void SHA256(unsigned char* input, int len, unsigned char* output)
+{
+    SHA256_CTX ctx;
+    SHA256_Init(&ctx);
+    SHA256_Update(&ctx, (uint8_t*)input, len);
+    SHA256_Final(&ctx, (uint8_t*)output);
+}
+
diff --git a/src/primitives/block.cpp b/src/primitives/block.cpp
index 76f16079b..1aeabb3d5 100644
--- a/src/primitives/block.cpp
+++ b/src/primitives/block.cpp
@@ -18,7 +18,7 @@ uint256 CBlockHeader::GetHash() const
 uint256 CBlockHeader::GetPoWHash() const
 {
     uint256 thash;
-    scrypt_1024_1_1_256(BEGIN(nVersion), BEGIN(thash));
+    scrypt_1024_1_1_256((char*)&nVersion, (char*)&thash);
     return thash;
 }
 
diff --git a/src/test/blockencodings_tests.cpp b/src/test/blockencodings_tests.cpp
index 14cf1a4a7..fb3158b07 100644
--- a/src/test/blockencodings_tests.cpp
+++ b/src/test/blockencodings_tests.cpp
@@ -44,7 +44,7 @@ static CBlock BuildBlockTestCase() {
     bool mutated;
     block.hashMerkleRoot = BlockMerkleRoot(block, &mutated);
     assert(!mutated);
-    while (!CheckProofOfWork(block.GetHash(), block.nBits, Params().GetConsensus())) ++block.nNonce;
+    while (!CheckProofOfWork(block.GetPoWHash(), block.nBits, Params().GetConsensus())) ++block.nNonce;
     return block;
 }
 
@@ -275,7 +275,7 @@ BOOST_AUTO_TEST_CASE(EmptyBlockRoundTripTest)
     bool mutated;
     block.hashMerkleRoot = BlockMerkleRoot(block, &mutated);
     assert(!mutated);
-    while (!CheckProofOfWork(block.GetHash(), block.nBits, Params().GetConsensus())) ++block.nNonce;
+    while (!CheckProofOfWork(block.GetPoWHash(), block.nBits, Params().GetConsensus())) ++block.nNonce;
 
     // Test simple header round-trip with only coinbase
     {
diff --git a/src/test/blockfilter_index_tests.cpp b/src/test/blockfilter_index_tests.cpp
index 753c1bb5f..8b76d30ac 100644
--- a/src/test/blockfilter_index_tests.cpp
+++ b/src/test/blockfilter_index_tests.cpp
@@ -82,7 +82,7 @@ CBlock BuildChainTestingSetup::CreateBlock(const CBlockIndex* prev,
     unsigned int extraNonce = 0;
     IncrementExtraNonce(&block, prev, extraNonce);
 
-    while (!CheckProofOfWork(block.GetHash(), block.nBits, chainparams.GetConsensus())) ++block.nNonce;
+    while (!CheckProofOfWork(block.GetPoWHash(), block.nBits, chainparams.GetConsensus())) ++block.nNonce;
 
     return block;
 }