* src/itdb_sha1.c: (generate_key): move cryptic calculations

into the precomputed tables. Patch by Simon Schulz.


git-svn-id: https://gtkpod.svn.sf.net/svnroot/gtkpod/libgpod/trunk@1720 f01d2545-417e-4e96-918e-98f8d0dbbcb6

2 files changed, 73 insertions, 108 deletions

diff --git a/ChangeLog b/ChangeLog
index 06c648a..9a53a46 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
 2007-10-05  Christophe Fergeau  <teuf@gnome.org>
 
+	* src/itdb_sha1.c: (generate_key): move cryptic calculations 
+	into the precomputed tables. Patch by Simon Schulz.
+
+2007-10-05  Christophe Fergeau  <teuf@gnome.org>
+
 	* src/itdb_device.c:
           Remove duplicate reference to ithmb file
 
diff --git a/src/itdb_sha1.c b/src/itdb_sha1.c
index 0ec6c54..7e6d3b1 100644
--- a/src/itdb_sha1.c
+++ b/src/itdb_sha1.c
@@ -38,109 +38,74 @@
 #include "itdb_sha1.h"
 #include "sha1.h"
 
-static const unsigned char invTable[256] = {
-    0x74, 0x85, 0x96, 0xA7, 0xB8, 0xC9, 0xDA, 0xEB,
-    0xFC, 0x0D, 0x1E, 0x2F, 0x40, 0x51, 0x62, 0x73,
-    0x84, 0x95, 0xA6, 0xB7, 0xC8, 0xD9, 0xEA, 0xFB,
-    0x0C, 0x1D, 0x2E, 0x3F, 0x50, 0x61, 0x72, 0x83,
-    0x94, 0xA5, 0xB6, 0xC7, 0xD8, 0xE9, 0xFA, 0x0B,
-    0x1C, 0x2D, 0x3E, 0x4F, 0x60, 0x71, 0x82, 0x93,
-    0xA4, 0xB5, 0xC6, 0xD7, 0xE8, 0xF9, 0x0A, 0x1B,
-    0x2C, 0x3D, 0x4E, 0x5F, 0x70, 0x81, 0x92, 0xA3,
-    0xB4, 0xC5, 0xD6, 0xE7, 0xF8, 0x09, 0x1A, 0x2B,
-    0x3C, 0x4D, 0x5E, 0x6F, 0x80, 0x91, 0xA2, 0xB3,
-    0xC4, 0xD5, 0xE6, 0xF7, 0x08, 0x19, 0x2A, 0x3B,
-    0x4C, 0x5D, 0x6E, 0x7F, 0x90, 0xA1, 0xB2, 0xC3,
-    0xD4, 0xE5, 0xF6, 0x07, 0x18, 0x29, 0x3A, 0x4B,
-    0x5C, 0x6D, 0x7E, 0x8F, 0xA0, 0xB1, 0xC2, 0xD3,
-    0xE4, 0xF5, 0x06, 0x17, 0x28, 0x39, 0x4A, 0x5B,
-    0x6C, 0x7D, 0x8E, 0x9F, 0xB0, 0xC1, 0xD2, 0xE3,
-    0xF4, 0x05, 0x16, 0x27, 0x38, 0x49, 0x5A, 0x6B,
-    0x7C, 0x8D, 0x9E, 0xAF, 0xC0, 0xD1, 0xE2, 0xF3,
-    0x04, 0x15, 0x26, 0x37, 0x48, 0x59, 0x6A, 0x7B,
-    0x8C, 0x9D, 0xAE, 0xBF, 0xD0, 0xE1, 0xF2, 0x03,
-    0x14, 0x25, 0x36, 0x47, 0x58, 0x69, 0x7A, 0x8B,
-    0x9C, 0xAD, 0xBE, 0xCF, 0xE0, 0xF1, 0x02, 0x13,
-    0x24, 0x35, 0x46, 0x57, 0x68, 0x79, 0x8A, 0x9B,
-    0xAC, 0xBD, 0xCE, 0xDF, 0xF0, 0x01, 0x12, 0x23,
-    0x34, 0x45, 0x56, 0x67, 0x78, 0x89, 0x9A, 0xAB,
-    0xBC, 0xCD, 0xDE, 0xEF, 0x00, 0x11, 0x22, 0x33,
-    0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0xAA, 0xBB,
-    0xCC, 0xDD, 0xEE, 0xFF, 0x10, 0x21, 0x32, 0x43,
-    0x54, 0x65, 0x76, 0x87, 0x98, 0xA9, 0xBA, 0xCB,
-    0xDC, 0xED, 0xFE, 0x0F, 0x20, 0x31, 0x42, 0x53,
-    0x64, 0x75, 0x86, 0x97, 0xA8, 0xB9, 0xCA, 0xDB,
-    0xEC, 0xFD, 0x0E, 0x1F, 0x30, 0x41, 0x52, 0x63
-};
-
 static const unsigned char table1[256] = {
-    0x3A, 0x3F, 0x3E, 0x72, 0xBD, 0xA2, 0xD6, 0xB4,
-    0x63, 0xC0, 0x6E, 0x62, 0x59, 0x1E, 0xE2, 0x71,
-    0xB5, 0x0D, 0xE8, 0x0C, 0x25, 0x38, 0xCE, 0x23,
-    0x7C, 0xB7, 0xAD, 0x16, 0xDF, 0x47, 0x3D, 0xB3,
-    0x7E, 0x8C, 0xAA, 0x61, 0x31, 0x66, 0xBE, 0x4F,
-    0x97, 0x14, 0x54, 0xF0, 0x70, 0xEB, 0x30, 0xC4,
-    0x27, 0x4E, 0xFA, 0x1A, 0x2B, 0x11, 0xF4, 0x45,
-    0x8E, 0x5D, 0x73, 0xED, 0x22, 0x2E, 0x7D, 0xA4,
-    0x28, 0xDA, 0x2F, 0xC5, 0x92, 0x09, 0x05, 0x13,
-    0x9D, 0x32, 0x51, 0x4A, 0xC8, 0xBA, 0x96, 0xA7,
-    0x6A, 0x50, 0xF3, 0xBC, 0x93, 0xBF, 0xB0, 0xD2,
-    0xD5, 0x82, 0x19, 0x98, 0x35, 0xCF, 0x6B, 0xB6,
-    0x83, 0x56, 0x15, 0xF2, 0x9A, 0x9C, 0xCA, 0x74,
-    0x34, 0x58, 0x8D, 0xA6, 0x03, 0xFF, 0x46, 0x7B,
-    0xD0, 0x7A, 0x33, 0x76, 0xDD, 0xAC, 0xCB, 0x24,
-    0x7F, 0xB1, 0x85, 0x60, 0xC3, 0x26, 0x8A, 0x1D,
-    0x1C, 0x8F, 0x2A, 0xEF, 0x06, 0xDE, 0x67, 0x5E,
-    0xE7, 0xAE, 0xD9, 0xCC, 0x07, 0x6C, 0xF8, 0x0A,
-    0xD3, 0x40, 0x36, 0x1F, 0x2D, 0x95, 0x43, 0xDB,
-    0x01, 0x89, 0x4B, 0xF7, 0xB9, 0x39, 0xC2, 0x52,
-    0x53, 0xFD, 0x65, 0xF5, 0x68, 0xC1, 0xC7, 0x9F,
-    0x4D, 0xEA, 0xAF, 0x6D, 0x10, 0x44, 0x87, 0xD8,
-    0xEE, 0x1B, 0xFE, 0x3C, 0xDC, 0x84, 0x69, 0x48,
-    0x6F, 0xD1, 0x57, 0x55, 0xD4, 0xA5, 0x49, 0x5B,
-    0xE5, 0x0B, 0x94, 0xC9, 0x5F, 0xE1, 0x17, 0x81,
-    0xBB, 0xEC, 0xD7, 0xC6, 0x02, 0x4C, 0x42, 0x75,
-    0xA3, 0x99, 0xE4, 0xA1, 0x9B, 0x5A, 0xF1, 0x29,
-    0xA0, 0x64, 0x9E, 0x18, 0x41, 0x80, 0x2C, 0x79,
-    0x20, 0x8B, 0xAB, 0x90, 0x08, 0xB8, 0xA9, 0x77,
-    0x12, 0xF9, 0x0E, 0x88, 0xE9, 0x04, 0xFB, 0x86,
-    0x0F, 0xE0, 0xA8, 0x5C, 0xE6, 0x21, 0xCD, 0x3B,
-    0x00, 0x78, 0xFC, 0xF6, 0xE3, 0x37, 0xB2, 0x91
+	0x63, 0x7C, 0x77, 0x7B, 0xF2, 0x6B, 0x6F, 0xC5, 
+	0x30, 0x01, 0x67, 0x2B, 0xFE, 0xD7, 0xAB, 0x76,
+	0xCA, 0x82, 0xC9, 0x7D, 0xFA, 0x59, 0x47, 0xF0, 
+	0xAD, 0xD4, 0xA2, 0xAF, 0x9C, 0xA4, 0x72, 0xC0,
+	0xB7, 0xFD, 0x93, 0x26, 0x36, 0x3F, 0xF7, 0xCC, 
+	0x34, 0xA5, 0xE5, 0xF1, 0x71, 0xD8, 0x31, 0x15,
+	0x04, 0xC7, 0x23, 0xC3, 0x18, 0x96, 0x05, 0x9A, 
+	0x07, 0x12, 0x80, 0xE2, 0xEB, 0x27, 0xB2, 0x75,
+	0x09, 0x83, 0x2C, 0x1A, 0x1B, 0x6E, 0x5A, 0xA0, 
+	0x52, 0x3B, 0xD6, 0xB3, 0x29, 0xE3, 0x2F, 0x84,
+	0x53, 0xD1, 0x00, 0xED, 0x20, 0xFC, 0xB1, 0x5B, 
+	0x6A, 0xCB, 0xBE, 0x39, 0x4A, 0x4C, 0x58, 0xCF,
+	0xD0, 0xEF, 0xAA, 0xFB, 0x43, 0x4D, 0x33, 0x85, 
+	0x45, 0xF9, 0x02, 0x7F, 0x50, 0x3C, 0x9F, 0xA8,
+	0x51, 0xA3, 0x40, 0x8F, 0x92, 0x9D, 0x38, 0xF5, 
+	0xBC, 0xB6, 0xDA, 0x21, 0x10, 0xFF, 0xF3, 0xD2,
+	0xCD, 0x0C, 0x13, 0xEC, 0x5F, 0x97, 0x44, 0x17, 
+	0xC4, 0xA7, 0x7E, 0x3D, 0x64, 0x5D, 0x19, 0x73,
+	0x60, 0x81, 0x4F, 0xDC, 0x22, 0x2A, 0x90, 0x88, 
+	0x46, 0xEE, 0xB8, 0x14, 0xDE, 0x5E, 0x0B, 0xDB,
+	0xE0, 0x32, 0x3A, 0x0A, 0x49, 0x06, 0x24, 0x5C, 
+	0xC2, 0xD3, 0xAC, 0x62, 0x91, 0x95, 0xE4, 0x79,
+	0xE7, 0xC8, 0x37, 0x6D, 0x8D, 0xD5, 0x4E, 0xA9, 
+	0x6C, 0x56, 0xF4, 0xEA, 0x65, 0x7A, 0xAE, 0x08,
+	0xBA, 0x78, 0x25, 0x2E, 0x1C, 0xA6, 0xB4, 0xC6, 
+	0xE8, 0xDD, 0x74, 0x1F, 0x4B, 0xBD, 0x8B, 0x8A,
+	0x70, 0x3E, 0xB5, 0x66, 0x48, 0x03, 0xF6, 0x0E, 
+	0x61, 0x35, 0x57, 0xB9, 0x86, 0xC1, 0x1D, 0x9E,
+	0xE1, 0xF8, 0x98, 0x11, 0x69, 0xD9, 0x8E, 0x94, 
+	0x9B, 0x1E, 0x87, 0xE9, 0xCE, 0x55, 0x28, 0xDF,
+	0x8C, 0xA1, 0x89, 0x0D, 0xBF, 0xE6, 0x42, 0x68, 
+	0x41, 0x99, 0x2D, 0x0F, 0xB0, 0x54, 0xBB, 0x16
 };
 
 static const unsigned char table2[256] = {
-    0xF3, 0xE4, 0x1B, 0x38, 0xE5, 0x6F, 0xE8, 0x9D,
-    0x3E, 0x55, 0xBA, 0xC7, 0xAC, 0xEA, 0x66, 0xA2,
-    0xB9, 0x7A, 0x34, 0x43, 0x02, 0x4E, 0xFE, 0x36,
-    0x41, 0x57, 0x1A, 0xB1, 0x31, 0x87, 0x04, 0x52,
-    0x21, 0x22, 0xE1, 0x13, 0x7F, 0x03, 0x3A, 0x90,
-    0xF7, 0x69, 0x78, 0x12, 0x83, 0x0B, 0x9A, 0x97,
-    0x4D, 0xB7, 0x8C, 0xBF, 0x2D, 0x94, 0xD1, 0x93,
-    0x2F, 0x42, 0x23, 0xA4, 0xE0, 0x92, 0xDC, 0x68,
-    0xD3, 0xDD, 0xAF, 0x91, 0x9F, 0xED, 0x3D, 0x8F,
-    0xA1, 0x51, 0xD9, 0xE9, 0x70, 0x28, 0xEF, 0xB3,
-    0x49, 0xA5, 0x0D, 0xC5, 0xD0, 0x60, 0xB4, 0x2B,
-    0x07, 0xF8, 0xDF, 0xE6, 0x16, 0xC0, 0x30, 0x71,
-    0x85, 0xFD, 0x72, 0x95, 0x29, 0x79, 0x0A, 0x7B,
-    0x46, 0x11, 0x7D, 0x88, 0x1D, 0x2A, 0x48, 0x1F,
-    0x45, 0x89, 0x47, 0xEE, 0xBB, 0xBE, 0x6E, 0xC3,
-    0x6C, 0xCE, 0x10, 0x5A, 0x2C, 0xCA, 0xFB, 0xB2,
-    0xCB, 0x1C, 0x9C, 0xEC, 0x2E, 0x56, 0x59, 0x9B,
-    0xA6, 0x53, 0xAE, 0x17, 0x25, 0xC1, 0x3F, 0x6A,
-    0x0F, 0x09, 0x01, 0xA3, 0xD6, 0xA0, 0xD8, 0x08,
-    0xE3, 0x74, 0x06, 0x6D, 0x19, 0x98, 0x1E, 0x77,
-    0x76, 0xBC, 0xEB, 0x3C, 0xB0, 0xC4, 0xC8, 0x64,
-    0x0E, 0x86, 0x63, 0xD7, 0xDB, 0xBD, 0xA7, 0x82,
-    0x39, 0x4F, 0x27, 0xD2, 0x5F, 0x73, 0xF4, 0x75,
-    0x6B, 0xC2, 0xD5, 0x67, 0x5D, 0x80, 0xAB, 0x81,
-    0xDE, 0xF0, 0xAD, 0xAA, 0xCD, 0xB6, 0xF6, 0x7C,
-    0xFC, 0x33, 0x05, 0x14, 0x96, 0x15, 0xC9, 0x9E,
-    0x35, 0x5C, 0x7E, 0x44, 0x54, 0x58, 0x3B, 0x40,
-    0x20, 0xA8, 0x8B, 0x5E, 0x4A, 0x24, 0x99, 0x8E,
-    0xF5, 0xB5, 0x62, 0x00, 0x37, 0x5B, 0x18, 0x65,
-    0x8D, 0x32, 0xE2, 0xF9, 0xDA, 0x8A, 0xD4, 0xCC,
-    0x26, 0xF2, 0xF1, 0xE7, 0x4B, 0xC6, 0xCF, 0xFF,
-    0x4C, 0x84, 0x61, 0xFA, 0xB8, 0x0C, 0xA9, 0x50
+	0x52, 0x09, 0x6A, 0xD5, 0x30, 0x36, 0xA5, 0x38, 
+	0xBF, 0x40, 0xA3, 0x9E, 0x81, 0xF3, 0xD7, 0xFB,
+	0x7C, 0xE3, 0x39, 0x82, 0x9B, 0x2F, 0xFF, 0x87, 
+	0x34, 0x8E, 0x43, 0x44, 0xC4, 0xDE, 0xE9, 0xCB,
+	0x54, 0x7B, 0x94, 0x32, 0xA6, 0xC2, 0x23, 0x3D, 
+	0xEE, 0x4C, 0x95, 0x0B, 0x42, 0xFA, 0xC3, 0x4E,
+	0x08, 0x2E, 0xA1, 0x66, 0x28, 0xD9, 0x24, 0xB2, 
+	0x76, 0x5B, 0xA2, 0x49, 0x6D, 0x8B, 0xD1, 0x25,
+	0x72, 0xF8, 0xF6, 0x64, 0x86, 0x68, 0x98, 0x16, 
+	0xD4, 0xA4, 0x5C, 0xCC, 0x5D, 0x65, 0xB6, 0x92,
+	0x6C, 0x70, 0x48, 0x50, 0xFD, 0xED, 0xB9, 0xDA, 
+	0x5E, 0x15, 0x46, 0x57, 0xA7, 0x8D, 0x9D, 0x84,
+	0x90, 0xD8, 0xAB, 0x00, 0x8C, 0xBC, 0xD3, 0x0A, 
+	0xF7, 0xE4, 0x58, 0x05, 0xB8, 0xB3, 0x45, 0x06,
+	0xD0, 0x2C, 0x1E, 0x8F, 0xCA, 0x3F, 0x0F, 0x02, 
+	0xC1, 0xAF, 0xBD, 0x03, 0x01, 0x13, 0x8A, 0x6B,
+	0x3A, 0x91, 0x11, 0x41, 0x4F, 0x67, 0xDC, 0xEA, 
+	0x97, 0xF2, 0xCF, 0xCE, 0xF0, 0xB4, 0xE6, 0x73,
+	0x96, 0xAC, 0x74, 0x22, 0xE7, 0xAD, 0x35, 0x85, 
+	0xE2, 0xF9, 0x37, 0xE8, 0x1C, 0x75, 0xDF, 0x6E,
+	0x47, 0xF1, 0x1A, 0x71, 0x1D, 0x29, 0xC5, 0x89, 
+	0x6F, 0xB7, 0x62, 0x0E, 0xAA, 0x18, 0xBE, 0x1B,
+	0xFC, 0x56, 0x3E, 0x4B, 0xC6, 0xD2, 0x79, 0x20, 
+	0x9A, 0xDB, 0xC0, 0xFE, 0x78, 0xCD, 0x5A, 0xF4,
+	0x1F, 0xDD, 0xA8, 0x33, 0x88, 0x07, 0xC7, 0x31, 
+	0xB1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xEC, 0x5F,
+	0x60, 0x51, 0x7F, 0xA9, 0x19, 0xB5, 0x4A, 0x0D, 
+	0x2D, 0xE5, 0x7A, 0x9F, 0x93, 0xC9, 0x9C, 0xEF,
+	0xA0, 0xE0, 0x3B, 0x4D, 0xAE, 0x2A, 0xF5, 0xB0, 
+	0xC8, 0xEB, 0xBB, 0x3C, 0x83, 0x53, 0x99, 0x61,
+	0x17, 0x2B, 0x04, 0x7E, 0xBA, 0x77, 0xD6, 0x26, 
+	0xE1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0C, 0x7D
 };
 
 static const unsigned char fixed[18] = {
@@ -187,15 +152,10 @@ static unsigned char *generate_key (guint64 fwid)
         unsigned char hi = (cur_lcm & 0xFF00) >> 8;
         unsigned char lo = cur_lcm & 0xFF;
 
-        y[i*4] = ((table1[hi] * 0xB5) - 3);
-        y[i*4 + 1] = ((table2[hi] * 0xB7) + 0x49);
-        y[i*4 + 2] = ((table1[lo] * 0xB5) - 3);
-        y[i*4 + 3] = ((table2[lo] * 0xB7) + 0x49);
-    }
-
-    /* convert y */
-    for(i=0;i<16;i++){
-        y[i] = invTable[y[i]];
+        y[i*4    ] = table1[hi];
+        y[i*4 + 1] = table2[hi];
+        y[i*4 + 2] = table1[lo];
+        y[i*4 + 3] = table2[lo];
     }
 
     /* hash */