From 3e3ba6d98e979bb8610a7cfa907e6fac2ce27cd3 Mon Sep 17 00:00:00 2001
From: Skot Croshere <skot@geocene.com>
Date: Fri, 19 May 2023 22:47:10 -0400
Subject: [PATCH] flip the byte order of the midstate

---
 components/stratum/mining.c | 25 ++++++++++---------------
 components/stratum/utils.c  | 36 +++++++++++++++++++++++++++++++++++-
 2 files changed, 45 insertions(+), 16 deletions(-)

diff --git a/components/stratum/mining.c b/components/stratum/mining.c
index 3ab5449a..730c7a05 100644
--- a/components/stratum/mining.c
+++ b/components/stratum/mining.c
@@ -60,23 +60,18 @@ bm_job construct_bm_job(uint32_t version, const char * prev_block_hash, const ch
     uint8_t midstate_data[64];
 
     //print the header
-    printf("header: %08x%s%s%08x%08x000000000000008000000000000000000000000000000000000000000000000000000000\n", version, prev_block_hash, merkle_root, ntime, target);
+    //printf("header: %08x%s%s%08x%08x000000000000008000000000000000000000000000000000000000000000000000000000\n", version, prev_block_hash, merkle_root, ntime, target);
 
     memcpy(midstate_data, &version, 4); //copy version
-    // midstate_data[3] = version & 0xff;
-    // midstate_data[2] = (version >> 8) & 0xff;
-    // midstate_data[1] = (version >> 16) & 0xff;
-    // midstate_data[0] = (version >> 24) & 0xff;
-    swap_endian_words(prev_block_hash, midstate_data + 4);
-    //memcpy(midstate_data + 4, prev_block_bin, 32);
-    swap_endian_words(merkle_root, midstate_data + 36);
-    //memcpy(midstate_data + 36, merkle_root_bin, 28);
-    printf("midstate_data: ");
-    prettyHex(midstate_data, 64);
-    printf("\n");   
-    //single_sha256_bin(midstate_data, 64, new_job.midstate);
-    midstate_sha256_bin(midstate_data, 64, new_job.midstate);
-    reverse_bytes(new_job.midstate, 32);
+    swap_endian_words(prev_block_hash, midstate_data + 4); //copy prev_block_hash
+    swap_endian_words(merkle_root, midstate_data + 36); //copy merkle_root
+    // printf("midstate_data: ");
+    // prettyHex(midstate_data, 64);
+    // printf("\n");   
+
+    midstate_sha256_bin(midstate_data, 64, new_job.midstate); //make the midstate hash
+    reverse_bytes(new_job.midstate, 32); //reverse the midstate bytes for the BM job packet
+    
     memcpy(&new_job.merkle_root_end, merkle_root_bin + 28, 4);
 
     return new_job;
diff --git a/components/stratum/utils.c b/components/stratum/utils.c
index 2fd8e0ad..c4b516d1 100644
--- a/components/stratum/utils.c
+++ b/components/stratum/utils.c
@@ -5,6 +5,39 @@
 
 #include "mbedtls/sha256.h"
 
+#ifndef bswap_16
+#define bswap_16(a) ((((uint16_t) (a) << 8) & 0xff00) | (((uint16_t) (a) >> 8) & 0xff))
+#endif
+
+#ifndef bswap_32
+#define bswap_32(a) ((((uint32_t) (a) << 24) & 0xff000000) | \
+		     (((uint32_t) (a) << 8) & 0xff0000) | \
+     		     (((uint32_t) (a) >> 8) & 0xff00) | \
+     		     (((uint32_t) (a) >> 24) & 0xff))
+#endif
+
+uint32_t swab32(uint32_t v) {
+    return bswap_32(v);
+}
+
+void flip64bytes(void *dest_p, const void *src_p) {
+    uint32_t *dest = dest_p;
+    const uint32_t *src = src_p;
+    int i;
+
+    for (i = 0; i < 16; i++)
+        dest[i] = swab32(src[i]);
+}
+
+void flip32bytes(void *dest_p, const void *src_p) {
+    uint32_t *dest = dest_p;
+    const uint32_t *src = src_p;
+    int i;
+
+    for (i = 0; i < 8; i++)
+        dest[i] = swab32(src[i]);
+}
+
 
 int hex2char(uint8_t x, char *c)
 {
@@ -151,7 +184,8 @@ void midstate_sha256_bin( const uint8_t * data, const size_t data_len, uint8_t *
     mbedtls_sha256_starts_ret(&midstate, 0);
     mbedtls_sha256_update_ret(&midstate, data, 64);
 
-    memcpy(dest, midstate.state, 32);
+    //memcpy(dest, midstate.state, 32);
+    flip32bytes(dest, midstate.state);
 
 }