Merge pull request #668 from noproto/patch-1

xMasterX · web-flow · commit 09a66e2285d4 · 2023-12-14T01:06:03.000+03:00
Fix edge case -- 0.5% of UIDs got wrong result
diff --git a/applications/main/nfc/plugins/supported_cards/saflok.c b/applications/main/nfc/plugins/supported_cards/saflok.c
@@ -62,8 +62,8 @@ void generate_saflok_key(const uint8_t* uid, uint8_t* key) {
     uint8_t carry_sum = 0;
 
     for(int i = KEY_LENGTH - 1; i >= 0; i--, magickal_index--) {
-        uint16_t keysum = temp_key[i] + magic_table[magickal_index];
-        temp_key[i] = (keysum & 0xFF) + carry_sum;
+        uint16_t keysum = temp_key[i] + magic_table[magickal_index] + carry_sum;
+        temp_key[i] = (keysum & 0xFF);
         carry_sum = keysum >> 8;
     }
 

Original file line number	Diff line number	Diff line change
`@@ -62,8 +62,8 @@ void generate_saflok_key(const uint8_t* uid, uint8_t* key) {`
`62`	`62`	`uint8_t carry_sum = 0;`
`63`	`63`
`64`	`64`	`for(int i = KEY_LENGTH - 1; i >= 0; i--, magickal_index--) {`
`65`		`- uint16_t keysum = temp_key[i] + magic_table[magickal_index];`
`66`		`- temp_key[i] = (keysum & 0xFF) + carry_sum;`
	`65`	`+ uint16_t keysum = temp_key[i] + magic_table[magickal_index] + carry_sum;`
	`66`	`+ temp_key[i] = (keysum & 0xFF);`
`67`	`67`	`carry_sum = keysum >> 8;`
`68`	`68`	`}`
`69`	`69`