rxtools: lib/media/nand: Remove dependency on CTRDecryptor

rxtools: lib/media/nand: Remove dependency on CTRDecryptor rxtools: lib/media/crypto: Add aesCtr
roxas75 · Feb 29, 2016 · a762bc1 · a762bc1
1 parent 9ead299
commit a762bc1
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Showing 3 changed files with 52 additions and 23 deletions.
diff --git a/rxtools/source/include/lib/crypto.h b/rxtools/source/include/lib/crypto.h
@@ -59,3 +59,4 @@ void aesSelKey(uint32_t keyno);
 void aesSetCtr(void* iv);
 void aesAddCtr(void* ctr, uint32_t carry);
 void aesDecrypt(void *dst, const void *src, uint16_t blocks, uint32_t mode);
+void aesCtr(void *dst, const void *src, size_t n, void *ctr);
diff --git a/rxtools/source/lib/crypto.c b/rxtools/source/lib/crypto.c
@@ -74,6 +74,18 @@ static void fifo(const void* inbuf, void* outbuf, size_t blocks)
     }
 }
 
+static void start(uint32_t mode)
+{
+    *REG_AESCNT = mode |
+                  AES_CNT_START |
+                  AES_CNT_INPUT_ORDER |
+                  AES_CNT_OUTPUT_ORDER |
+                  AES_CNT_INPUT_ENDIAN |
+                  AES_CNT_OUTPUT_ENDIAN |
+                  AES_CNT_FLUSH_READ |
+                  AES_CNT_FLUSH_WRITE;
+}
+
 void aesSetKeyX(uint8_t keyslot, void* keyx)
 {
     uint32_t * _keyx = (uint32_t*)keyx;
@@ -178,13 +190,25 @@ void aesDecrypt(void *dst, const void *src, uint16_t blocks, uint32_t mode)
 {
     *REG_AESCNT = 0;
     *REG_AESBLKCNT = blocks << 16;
-    *REG_AESCNT = mode |
-                  AES_CNT_START |
-                  AES_CNT_INPUT_ORDER |
-                  AES_CNT_OUTPUT_ORDER |
-                  AES_CNT_INPUT_ENDIAN |
-                  AES_CNT_OUTPUT_ENDIAN |
-                  AES_CNT_FLUSH_READ |
-                  AES_CNT_FLUSH_WRITE;
+    start(mode);
     fifo(src, dst, blocks);
 }
+
+void aesCtr(void *dst, const void *src, size_t n, void *ctr)
+{
+    *REG_AESBLKCNT = UINT16_MAX << 16;
+    while (n >= UINT16_MAX) {
+        aesSetCtr(ctr);
+        start(AES_CTR_MODE);
+        fifo(src, dst, UINT16_MAX);
+        src = (void *)((uintptr_t)src + UINT16_MAX * AES_BLOCK_SIZE);
+        dst = (void *)((uintptr_t)dst + UINT16_MAX * AES_BLOCK_SIZE);
+        n -= UINT16_MAX;
+        aesAddCtr(ctr, UINT16_MAX);
+    }
+
+    *REG_AESBLKCNT = n << 16;
+    aesSetCtr(ctr);
+    start(AES_CTR_MODE);
+    fifo(src, dst, n);
+}
diff --git a/rxtools/source/lib/media/nand.c b/rxtools/source/lib/media/nand.c
@@ -16,7 +16,6 @@
  */
 
 #include <lib/mpcore.h>
-#include <features/decryption.h>
 #include <lib/crypto.h>
 #include <lib/media/tmio.h>
 #include <lib/media/nand.h>
@@ -95,42 +94,47 @@ void GetNANDCTR(uint8_t *ctr) {
 	for (int i = 0; i < 16; i++) { *(ctr + i) = NANDCTR[i]; }
 }
 
-static void cryptNand(enum nandPart part, uint32_t sector, void *p, uint32_t n)
+static int cryptNand(enum nandPart part, uint32_t sector, void *p, uint32_t n)
 {
-	PartitionInfo info;
+	const uint32_t sectorBlocks = 512 / AES_BLOCK_SIZE;
 	uint8_t ctr[AES_BLOCK_SIZE];
+	uint32_t key;
 
-	GetNANDCTR(ctr);
-	aesAddCtr(ctr, part / 16 + sector * 0x20);
-	info.ctr = ctr;
-	info.buffer = p;
-	info.size = n * 0x200;
-	info.keyY = NULL;
 	switch (part) {
 		case TWLN:
 		case TWLP:
-			info.keyslot = 0x3;
+			key = 0x3;
 			break;
 
 		case AGB_SAVE:
-			info.keyslot = 0x7;
+			key = 0x7;
 			break;
 
 		case FIRM0:
 		case FIRM1:
-			info.keyslot = 0x6;
+			key = 0x6;
 			break;
 
 		case CTRNAND:
-			info.keyslot = 0x4;
+			key = 0x4;
 			break;
 
 		case KTR_CTRNAND:
-			info.keyslot = 0x5;
+			key = 0x5;
 			break;
+
+		default:
+			return -1;
 	}
 
-	DecryptPartition(&info);
+	aesSelKey(key);
+
+	GetNANDCTR(ctr);
+	aesAddCtr(ctr, part / 16 + sector * sectorBlocks);
+
+	aesCtr(p, p, n * sectorBlocks, ctr);
+
+	return 0;
 }
 
 void nand_readsectors(uint32_t sector_no, uint32_t numsectors, uint8_t *out, unsigned int partition) {