From 0a20fedfda988c5a8d422974ca6d21a9b4f42f2c Mon Sep 17 00:00:00 2001
From: rdanbrook <1869094+rdanbrook@users.noreply.github.com>
Date: Sun, 28 Apr 2019 21:06:43 -0400
Subject: [PATCH] Fixed hashing and added ability to load a ROM directly from
 memory

---
 core/hash.c     | 15 ++-----------
 core/hash.h     |  2 +-
 core/loadrom.c  | 56 ++++++++++++++++++++++++++++++++++++++++++++++---
 core/loadrom.h  |  1 +
 core/system.h   |  2 +-
 shell/smsplus.c |  7 ++++++-
 6 files changed, 64 insertions(+), 19 deletions(-)

diff --git a/core/hash.c b/core/hash.c
index 6fe60c8..03813f4 100644
--- a/core/hash.c
+++ b/core/hash.c
@@ -109,23 +109,12 @@ void sha1_final(sha1_context_t* context, uint8_t digest[SHA1_DIGEST_SIZE]) {
 	memset(finalcount, 0, 8);
 }
 
-const char* sha1(const void *buf, size_t size) {
-
+void sha1(uint8_t *digest, const void *buf, size_t size) {
+	// Do the SHA1 hash operation
 	sha1_context_t context;
-	uint8_t digest[SHA1_DIGEST_SIZE];
-	
 	sha1_init(&context);
 	sha1_update(&context, buf, size);
 	sha1_final(&context, digest);
-	
-	char strbuf[SHA1_DIGEST_SIZE * 2 + 1];
-	static char checksum[SHA1_DIGEST_SIZE * 2 + 1];
-	for (int i = 0; i < SHA1_DIGEST_SIZE; i++) {
-		snprintf(strbuf, sizeof(strbuf), "%s", checksum);
-		snprintf(checksum, sizeof(checksum), "%s%02X", strbuf, digest[i]);
-	}
-
-	return checksum;
 }
 
 static uint32_t crc32_tab[] = {
diff --git a/core/hash.h b/core/hash.h
index c538b14..db0499a 100644
--- a/core/hash.h
+++ b/core/hash.h
@@ -26,7 +26,7 @@ typedef struct {
 	uint8_t  buffer[64];
 } sha1_context_t;
 
-const char* sha1(const void *buf, size_t size);
+void sha1(uint8_t *digest, const void *buf, size_t size);
 void sha1_init(sha1_context_t* context);
 void sha1_transform(uint32_t state[5], const uint8_t buffer[64]);
 void sha1_update(sha1_context_t* context, const uint8_t* data, const size_t len);
diff --git a/core/loadrom.c b/core/loadrom.c
index d067b26..e53d55f 100644
--- a/core/loadrom.c
+++ b/core/loadrom.c
@@ -67,9 +67,11 @@ int load_rom(char *filename)
 
     cart.pages = (size / 0x4000);
     cart.crc = crc32(0L, cart.rom, size);
-    
-    const char *shabuf = sha1(cart.rom, sizeof(cart.rom));
-    snprintf(cart.sha1, sizeof(cart.sha1), "%s", shabuf);
+
+    uint8_t *temprom = malloc(size * sizeof(uint8_t));
+    memcpy(temprom, cart.rom, size);
+    sha1(cart.sha1, temprom, size);
+    free(temprom);
 
     /* Assign default settings (US NTSC machine) */
     cart.mapper     = MAPPER_SEGA;
@@ -93,3 +95,51 @@ int load_rom(char *filename)
     return 1;
 }
 
+int load_rom_mem(uint8_t *rom, size_t size)
+{
+    int i;
+
+    if(cart.rom) { free(cart.rom); }
+
+    cart.rom = (uint8_t*)malloc(size * sizeof(uint8_t));
+    memcpy(cart.rom, rom, size);
+    
+    /* Don't load games smaller than 16K */
+    if(size < 0x4000) return 0;
+
+    /* Take care of image header, if present */
+    if((size / 512) & 1)
+    {
+        size -= 512;
+        memmove(cart.rom, cart.rom + 512, size);
+    }
+
+    cart.pages = (size / 0x4000);
+    cart.crc = crc32(0L, cart.rom, size);
+
+    uint8_t *temprom = malloc(size * sizeof(uint8_t));
+    memcpy(temprom, cart.rom, size);
+    sha1(cart.sha1, temprom, size);
+    free(temprom);
+
+    /* Assign default settings (US NTSC machine) */
+    cart.mapper     = MAPPER_SEGA;
+    sms.display     = DISPLAY_NTSC;
+    sms.territory   = TERRITORY_EXPORT;
+
+    /* Look up mapper in game list */
+    for(i = 0; game_list[i].name != NULL; i++)
+    {
+        if(cart.crc == game_list[i].crc)
+        {
+            cart.mapper     = game_list[i].mapper;
+            sms.display     = game_list[i].display;
+            sms.territory   = game_list[i].territory;
+        }
+    }
+
+    system_assign_device(PORT_A, DEVICE_PAD2B);
+    system_assign_device(PORT_B, DEVICE_PAD2B);
+
+    return 1;
+}
diff --git a/core/loadrom.h b/core/loadrom.h
index b6b925a..565768d 100644
--- a/core/loadrom.h
+++ b/core/loadrom.h
@@ -3,6 +3,7 @@
 
 /* Function prototypes */
 int load_rom(char *filename);
+int load_rom_mem(uint8_t *rom, size_t size);
 
 #endif /* _LOADROM_H_ */
 
diff --git a/core/system.h b/core/system.h
index 1495216..abbee63 100644
--- a/core/system.h
+++ b/core/system.h
@@ -43,7 +43,7 @@ typedef struct
     uint8_t *rom;
     uint8_t pages;
     uint32_t crc;
-    char sha1[41];
+    uint8_t sha1[20];
     uint32_t sram_crc;
     int mapper;
     uint8_t sram[0x8000];
diff --git a/shell/smsplus.c b/shell/smsplus.c
index 7c078ff..d5e4fdb 100644
--- a/shell/smsplus.c
+++ b/shell/smsplus.c
@@ -386,7 +386,12 @@ int main (int argc, char *argv[]) {
 	}
 	
 	fprintf(stdout, "CRC : %08X\n", cart.crc);
-	fprintf(stdout, "SHA1: %s\n", cart.sha1);
+	//fprintf(stdout, "SHA1: %s\n", cart.sha1);
+	fprintf(stdout, "SHA1: ");
+	for (int i = 0; i < SHA1_DIGEST_SIZE; i++) {
+		fprintf(stdout, "%02X", cart.sha1[i]);
+	}
+	fprintf(stdout, "\n");
 	
 	// Set defaults
 	settings.video_scale = 2;