From c1c5fb1974203abf974d6ad359f22dd64b203e45 Mon Sep 17 00:00:00 2001
From: Matteo Brichese <matteo.brichese@wunderbar.com>
Date: Tue, 6 Jun 2017 13:33:36 -0700
Subject: added AES192 and 256

---
 aes.c | 30 +++++++++++++++---------------
 1 file changed, 15 insertions(+), 15 deletions(-)

(limited to 'aes.c')

diff --git a/aes.c b/aes.c
index 6a2a531..e58498f 100644
--- a/aes.c
+++ b/aes.c
@@ -42,6 +42,7 @@ NOTE:   String length must be evenly divisible by 16byte (str_len % 16 == 0)
 /*****************************************************************************/
 // The number of columns comprising a state in AES. This is a constant in AES. Value=4
 #define Nb 4
+#define BLOCKLEN 16 //Block length in bytes AES is 128b block only
 
 #ifdef AES256
     #define Nk 8
@@ -177,7 +178,7 @@ static void KeyExpansion(void)
 
   // All other round keys are found from the previous round keys.
   //i == Nk
-  for(i = Nk; i < Nb * (Nr + 1); ++i)
+  for(; i < Nb * (Nr + 1); ++i)
   {
     {
       tempa[0]=RoundKey[(i-1) * 4 + 0];
@@ -494,7 +495,7 @@ void AES_ECB_decrypt(const uint8_t* input, const uint8_t* key, uint8_t *output,
 static void XorWithIv(uint8_t* buf)
 {
   uint8_t i;
-  for(i = 0; i < 16; ++i) //WAS for(i = 0; i < KEYLEN; ++i) but the block in AES is always 128bit so 16 bytes!
+  for(i = 0; i < BLOCKLEN; ++i) //WAS for(i = 0; i < KEYLEN; ++i) but the block in AES is always 128bit so 16 bytes!
   {
     buf[i] ^= Iv[i];
   }
@@ -503,9 +504,9 @@ static void XorWithIv(uint8_t* buf)
 void AES_CBC_encrypt_buffer(uint8_t* output, uint8_t* input, uint32_t length, const uint8_t* key, const uint8_t* iv)
 {
   uintptr_t i;
-  uint8_t extra = length % 16; /* Remaining bytes in the last non-full block */
+  uint8_t extra = length % BLOCKLEN; /* Remaining bytes in the last non-full block */
 
-  memcpy(output, input, 16);
+  memcpy(output, input, BLOCKLEN);
   state = (state_t*)output;
 
   // Skip the key expansion if key is passed as 0
@@ -520,21 +521,20 @@ void AES_CBC_encrypt_buffer(uint8_t* output, uint8_t* input, uint32_t length, co
     Iv = (uint8_t*)iv;
   }
 
-  for(i = 0; i < length; i += 16)
+  for(i = 0; i < length; i += BLOCKLEN)
   {
     XorWithIv(input);
-    memcpy(output, input, 16);
+    memcpy(output, input, BLOCKLEN);
     state = (state_t*)output;
     Cipher();
     Iv = output;
-    input += 16;
-    output += 16;
+    input += BLOCKLEN;
+    output += BLOCKLEN;
     //printf("Step %d - %d", i/16, i);
   }
 
   if(extra)
   {
-    printf("NONO\n");
     memcpy(output, input, extra);
     state = (state_t*)output;
     Cipher();
@@ -544,9 +544,9 @@ void AES_CBC_encrypt_buffer(uint8_t* output, uint8_t* input, uint32_t length, co
 void AES_CBC_decrypt_buffer(uint8_t* output, uint8_t* input, uint32_t length, const uint8_t* key, const uint8_t* iv)
 {
   uintptr_t i;
-  uint8_t extra = length % 16; /* Remaining bytes in the last non-full block */
+  uint8_t extra = length % BLOCKLEN; /* Remaining bytes in the last non-full block */
 
-  memcpy(output, input, 16);
+  memcpy(output, input, BLOCKLEN);
   state = (state_t*)output;
   
   // Skip the key expansion if key is passed as 0
@@ -562,15 +562,15 @@ void AES_CBC_decrypt_buffer(uint8_t* output, uint8_t* input, uint32_t length, co
     Iv = (uint8_t*)iv;
   }
 
-  for(i = 0; i < length; i += 16)
+  for(i = 0; i < length; i += BLOCKLEN)
   {
-    memcpy(output, input, 16);
+    memcpy(output, input, BLOCKLEN);
     state = (state_t*)output;
     InvCipher();
     XorWithIv(output);
     Iv = input;
-    input += 16;
-    output += 16;
+    input += BLOCKLEN;
+    output += BLOCKLEN;
   }
 
   if(extra)
-- 
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