Cleanup

src/descrambler/libaesdec/libaesdec.c

@@ -2,7 +2,7 @@
  * libaesdec.c
  *
  *  Created on: Jun 22, 2014
- *      Author: root
+ *      Author: spdfrk1
  */
 
 #include <sys/types.h>
@@ -14,16 +14,18 @@
 
 #include "libaesdec.h"
 
+//-----allocate key structure
 struct aes_keys_t {
 	AES_KEY even;
 	AES_KEY odd;
 };
 
-// Even and Odd cw represent one full 128-bit AES key
+//-----even cw represents one full 128-bit AES key
 void aes_set_even_control_word(void *keys, const unsigned char *pk) {
 	AES_set_decrypt_key(pk, 128, &((struct aes_keys_t *) keys)->even);
 }
 
+//-----odd cw represents one full 128-bit AES key
 void aes_set_odd_control_word(void *keys, const unsigned char *pk) {
 	AES_set_decrypt_key(pk, 128, &((struct aes_keys_t *) keys)->odd);
 }
@@ -35,8 +37,8 @@ void aes_set_control_words(void *keys, const unsigned char *ev,
 	AES_set_decrypt_key(od, 128, &((struct aes_keys_t *) keys)->odd);
 }
 
-//-----key structure
-void *aes_get_key_struct(void) {
+//-----allocate key structure
+void * aes_get_key_struct(void) {
 	struct aes_keys_t *keys = (struct aes_keys_t *) malloc(
 			sizeof(struct aes_keys_t));
 	if (keys) {
@@ -46,9 +48,10 @@ void *aes_get_key_struct(void) {
 	return keys;
 }
 
+//-----free key structure
 void aes_free_key_struct(void *keys) {
-	free(keybuffer);
-	return free(keys);
+	if (keys)
+		free(keys);
 }
 
 //----- decrypt
@@ -57,35 +60,32 @@ void aes_decrypt_packet(void *keys, unsigned char *packet) {
 	unsigned char ev_od = 0;
 	int xc0, offset, n;
 	int len;
-	//int residue;
 	pkt = packet;
 	AES_KEY k;
 
-	// TODO check all flags
 	xc0 = pkt[3] & 0xc0;
-	if (xc0 == 0x00) {//skip clear pkt
+	//skip clear pkt
+	if (xc0 == 0x00) {
 		return;
 	}
-	if (xc0 == 0x40) { //skip reserved pkt
+	//skip reserved pkt
+	if (xc0 == 0x40) { 
 		return;
 	}	
 	if (xc0 == 0x80 || xc0 == 0xc0) { // encrypted 
 		ev_od = (xc0 & 0x40) >> 6; // 0 even, 1 odd
 		pkt[3] &= 0x3f;  // consider it decrypted now
-		if (pkt[3] & 0x20) { // incomplete packet  TODO Check this
+		if (pkt[3] & 0x20) { // incomplete packet
 			offset = 4 + pkt[4] + 1;
 			len = 188 - offset;
 			n = len >> 3;
-			//residue = len - (n << 3);
 			if (n == 0) { // decrypted==encrypted!
-				//DBG(fprintf(stderr,"DECRYPTED MINI!\n"));
 				return;  // this doesn't need more processing
 			}                	
 		} 
 		else {
 			len = 184;
 			offset = 4;
-			//residue = 0;
 		}
 	}
 	else {
@@ -103,5 +103,4 @@ void aes_decrypt_packet(void *keys, unsigned char *packet) {
 	for (i = offset; i <= (len - 16); i += 16) {
 		AES_ecb_encrypt(pkt + i, pkt + i, &k, AES_DECRYPT);
 	}
-	return;
 }