1 files changed, 157 insertions, 0 deletions

diff --git a/utils/nwztools/upgtools/keysig_search.c b/utils/nwztools/upgtools/keysig_search.c
new file mode 100644
index 0000000000..6054ea43ba
--- /dev/null
+++ b/utils/nwztools/upgtools/keysig_search.c
@@ -0,0 +1,157 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2012 Amaury Pouly
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+#include "keysig_search.h"
+#include "misc.h"
+#include "mg.h"
+#include <string.h>
+
+#define HEX_MAJ
+
+static uint8_t g_cipher[8];
+static keysig_notify_fn_t g_notify;
+static uint8_t g_key[8];
+static void *g_user;
+static bool is_hex[256];
+static bool is_init = false;
+#ifdef HEX_MAJ
+static char hex_digits[] = "02468ABEF";
+#else
+static char hex_digits[] = "02468abef";
+#endif
+
+static void keysig_search_init()
+{
+    if(is_init) return;
+    is_init = true;
+    memset(is_hex, 0, sizeof(is_hex));
+    for(int i = '0'; i <= '9'; i++)
+        is_hex[i] = true;
+#ifdef HEX_MAJ
+    for(int i = 'A'; i <= 'F'; i++)
+#else
+    for(int i = 'a'; i <= 'f'; i++)
+#endif
+        is_hex[i] = true;
+}
+
+static inline bool is_full_ascii(uint8_t *arr)
+{
+    for(int i = 0; i < 8; i++)
+        if(!is_hex[arr[i]])
+            return false;
+    return true;
+}
+
+static inline bool check_stupid()
+{
+    uint8_t res[8];
+    mg_decrypt_fw(g_cipher, 8, res, g_key);
+    if(is_full_ascii(res))
+        return g_notify(g_user, g_key, res);
+    return false;
+}
+
+static bool search_stupid_rec(int rem_digit, int rem_letter, int pos)
+{
+    if(pos == 8)
+        return check_stupid();
+    if(rem_digit > 0)
+    {
+        for(int i = '0'; i <= '9'; i += 2)
+        {
+            g_key[pos] = i;
+            if(search_stupid_rec(rem_digit - 1, rem_letter, pos + 1))
+                return true;
+        }
+    }
+    if(rem_letter > 0)
+    {
+#ifdef HEX_MAJ
+        for(int i = 'a' - 1; i <= 'f'; i += 2)
+#else
+        for(int i = 'A' - 1; i <= 'F'; i += 2)
+#endif
+        {
+            g_key[pos] = i;
+            if(search_stupid_rec(rem_digit, rem_letter - 1, pos + 1))
+                return true;
+        }
+    }
+    return false;
+}
+
+static bool search_stupid(int rem_digit, int rem_letter)
+{
+    return search_stupid_rec(rem_digit, rem_letter, 0);
+}
+
+bool keysig_search_ascii_stupid(uint8_t *cipher, keysig_notify_fn_t notify, void *user)
+{
+    keysig_search_init();
+    memcpy(g_cipher, cipher, 8);
+    g_notify = notify;
+    g_user = user;
+#if 1
+    return search_stupid(4, 4) ||
+        search_stupid(3, 5) || search_stupid(5, 3) ||
+        search_stupid(2, 6) || search_stupid(6, 2) ||
+        search_stupid(1, 7) || search_stupid(7, 1) ||
+        search_stupid(0, 8) || search_stupid(8, 0);
+#else
+#define do(i) for(int a##i = 0; a##i < sizeof(hex_digits); a##i++) { g_key[i] = hex_digits[a##i];
+#define od() }
+
+    do(0)do(1)do(2)do(3)do(4)do(5)do(6)do(7)
+        if(check_stupid()) return true;
+    od()od()od()od()od()od()od()od()
+#undef do
+#undef od
+    return false;
+#endif
+}
+
+bool keysig_search_ascii_brute(uint8_t *cipher, keysig_notify_fn_t notify, void *user)
+{
+    keysig_search_init();
+    return false;
+}
+
+struct keysig_search_desc_t keysig_search_desc[KEYSIG_SEARCH_LAST] =
+{
+    [KEYSIG_SEARCH_NONE] =
+    {
+        .name = "none",
+        .fn = NULL,
+        .comment = "don't use",
+    },
+    [KEYSIG_SEARCH_ASCII_STUPID] =
+    {
+        .name = "ascii-stupid",
+        .fn = keysig_search_ascii_stupid,
+        .comment = "Try to find a balance ascii key ignoring lsb"
+    },
+    [KEYSIG_SEARCH_ASCII_BRUTE] =
+    {
+        .name = "ascii-brute",
+        .fn = keysig_search_ascii_brute,
+        .comment = "Brute force all ASCII keys"
+    },
+};