-/* crypt.h -- base code for crypt/uncrypt ZIPfile\r
-\r
-\r
- Version 1.01e, February 12th, 2005\r
-\r
- Copyright (C) 1998-2005 Gilles Vollant\r
-\r
- This code is a modified version of crypting code in Infozip distribution\r
-\r
- The encryption/decryption parts of this source code (as opposed to the\r
- non-echoing password parts) were originally written in Europe. The\r
- whole source package can be freely distributed, including from the USA.\r
- (Prior to January 2000, re-export from the US was a violation of US law.)\r
-\r
- This encryption code is a direct transcription of the algorithm from\r
- Roger Schlafly, described by Phil Katz in the file appnote.txt. This\r
- file (appnote.txt) is distributed with the PKZIP program (even in the\r
- version without encryption capabilities).\r
-\r
- If you don't need crypting in your application, just define symbols\r
- NOCRYPT and NOUNCRYPT.\r
-\r
- This code support the "Traditional PKWARE Encryption".\r
-\r
- The new AES encryption added on Zip format by Winzip (see the page\r
- http://www.winzip.com/aes_info.htm ) and PKWare PKZip 5.x Strong\r
- Encryption is not supported.\r
-*/\r
-\r
-#define CRC32(c, b) ((*(pcrc_32_tab+(((int)(c) ^ (b)) & 0xff))) ^ ((c) >> 8))\r
-\r
-/***********************************************************************\r
- * Return the next byte in the pseudo-random sequence\r
- */\r
-static int decrypt_byte(unsigned long* pkeys, const unsigned long* pcrc_32_tab)\r
-{\r
- unsigned temp; /* POTENTIAL BUG: temp*(temp^1) may overflow in an\r
- * unpredictable manner on 16-bit systems; not a problem\r
- * with any known compiler so far, though */\r
-\r
- temp = ((unsigned)(*(pkeys+2)) & 0xffff) | 2;\r
- return (int)(((temp * (temp ^ 1)) >> 8) & 0xff);\r
-}\r
-\r
-/***********************************************************************\r
- * Update the encryption keys with the next byte of plain text\r
- */\r
-static int update_keys(unsigned long* pkeys,const unsigned long* pcrc_32_tab,int c)\r
-{\r
- (*(pkeys+0)) = CRC32((*(pkeys+0)), c);\r
- (*(pkeys+1)) += (*(pkeys+0)) & 0xff;\r
- (*(pkeys+1)) = (*(pkeys+1)) * 134775813L + 1;\r
- {\r
- register int keyshift = (int)((*(pkeys+1)) >> 24);\r
- (*(pkeys+2)) = CRC32((*(pkeys+2)), keyshift);\r
- }\r
- return c;\r
-}\r
-\r
-\r
-/***********************************************************************\r
- * Initialize the encryption keys and the random header according to\r
- * the given password.\r
- */\r
-static void init_keys(const char* passwd,unsigned long* pkeys,const unsigned long* pcrc_32_tab)\r
-{\r
- *(pkeys+0) = 305419896L;\r
- *(pkeys+1) = 591751049L;\r
- *(pkeys+2) = 878082192L;\r
- while (*passwd != '\0') {\r
- update_keys(pkeys,pcrc_32_tab,(int)*passwd);\r
- passwd++;\r
- }\r
-}\r
-\r
-#define zdecode(pkeys,pcrc_32_tab,c) \\r
- (update_keys(pkeys,pcrc_32_tab,c ^= decrypt_byte(pkeys,pcrc_32_tab)))\r
-\r
-#define zencode(pkeys,pcrc_32_tab,c,t) \\r
- (t=decrypt_byte(pkeys,pcrc_32_tab), update_keys(pkeys,pcrc_32_tab,c), t^(c))\r
-\r
-#ifdef INCLUDECRYPTINGCODE_IFCRYPTALLOWED\r
-\r
-#define RAND_HEAD_LEN 12\r
- /* "last resort" source for second part of crypt seed pattern */\r
-# ifndef ZCR_SEED2\r
-# define ZCR_SEED2 3141592654UL /* use PI as default pattern */\r
-# endif\r
-\r
-static int crypthead(passwd, buf, bufSize, pkeys, pcrc_32_tab, crcForCrypting)\r
- const char *passwd; /* password string */\r
- unsigned char *buf; /* where to write header */\r
- int bufSize;\r
- unsigned long* pkeys;\r
- const unsigned long* pcrc_32_tab;\r
- unsigned long crcForCrypting;\r
-{\r
- int n; /* index in random header */\r
- int t; /* temporary */\r
- int c; /* random byte */\r
- unsigned char header[RAND_HEAD_LEN-2]; /* random header */\r
- static unsigned calls = 0; /* ensure different random header each time */\r
-\r
- if (bufSize<RAND_HEAD_LEN)\r
- return 0;\r
-\r
- /* First generate RAND_HEAD_LEN-2 random bytes. We encrypt the\r
- * output of rand() to get less predictability, since rand() is\r
- * often poorly implemented.\r
- */\r
- if (++calls == 1)\r
- {\r
- srand((unsigned)(time(NULL) ^ ZCR_SEED2));\r
- }\r
- init_keys(passwd, pkeys, pcrc_32_tab);\r
- for (n = 0; n < RAND_HEAD_LEN-2; n++)\r
- {\r
- c = (rand() >> 7) & 0xff;\r
- header[n] = (unsigned char)zencode(pkeys, pcrc_32_tab, c, t);\r
- }\r
- /* Encrypt random header (last two bytes is high word of crc) */\r
- init_keys(passwd, pkeys, pcrc_32_tab);\r
- for (n = 0; n < RAND_HEAD_LEN-2; n++)\r
- {\r
- buf[n] = (unsigned char)zencode(pkeys, pcrc_32_tab, header[n], t);\r
- }\r
- buf[n++] = zencode(pkeys, pcrc_32_tab, (int)(crcForCrypting >> 16) & 0xff, t);\r
- buf[n++] = zencode(pkeys, pcrc_32_tab, (int)(crcForCrypting >> 24) & 0xff, t);\r
- return n;\r
-}\r
-\r
-#endif\r
+/* crypt.h -- base code for crypt/uncrypt ZIPfile
+
+
+ Version 1.01e, February 12th, 2005
+
+ Copyright (C) 1998-2005 Gilles Vollant
+
+ This code is a modified version of crypting code in Infozip distribution
+
+ The encryption/decryption parts of this source code (as opposed to the
+ non-echoing password parts) were originally written in Europe. The
+ whole source package can be freely distributed, including from the USA.
+ (Prior to January 2000, re-export from the US was a violation of US law.)
+
+ This encryption code is a direct transcription of the algorithm from
+ Roger Schlafly, described by Phil Katz in the file appnote.txt. This
+ file (appnote.txt) is distributed with the PKZIP program (even in the
+ version without encryption capabilities).
+
+ If you don't need crypting in your application, just define symbols
+ NOCRYPT and NOUNCRYPT.
+
+ This code support the "Traditional PKWARE Encryption".
+
+ The new AES encryption added on Zip format by Winzip (see the page
+ http://www.winzip.com/aes_info.htm ) and PKWare PKZip 5.x Strong
+ Encryption is not supported.
+*/
+
+#define CRC32(c, b) ((*(pcrc_32_tab+(((int)(c) ^ (b)) & 0xff))) ^ ((c) >> 8))
+
+/***********************************************************************
+ * Return the next byte in the pseudo-random sequence
+ */
+static int decrypt_byte(unsigned long* pkeys, const unsigned long* pcrc_32_tab)
+{
+ unsigned temp; /* POTENTIAL BUG: temp*(temp^1) may overflow in an
+ * unpredictable manner on 16-bit systems; not a problem
+ * with any known compiler so far, though */
+
+ temp = ((unsigned)(*(pkeys+2)) & 0xffff) | 2;
+ return (int)(((temp * (temp ^ 1)) >> 8) & 0xff);
+}
+
+/***********************************************************************
+ * Update the encryption keys with the next byte of plain text
+ */
+static int update_keys(unsigned long* pkeys,const unsigned long* pcrc_32_tab,int c)
+{
+ (*(pkeys+0)) = CRC32((*(pkeys+0)), c);
+ (*(pkeys+1)) += (*(pkeys+0)) & 0xff;
+ (*(pkeys+1)) = (*(pkeys+1)) * 134775813L + 1;
+ {
+ register int keyshift = (int)((*(pkeys+1)) >> 24);
+ (*(pkeys+2)) = CRC32((*(pkeys+2)), keyshift);
+ }
+ return c;
+}
+
+
+/***********************************************************************
+ * Initialize the encryption keys and the random header according to
+ * the given password.
+ */
+static void init_keys(const char* passwd,unsigned long* pkeys,const unsigned long* pcrc_32_tab)
+{
+ *(pkeys+0) = 305419896L;
+ *(pkeys+1) = 591751049L;
+ *(pkeys+2) = 878082192L;
+ while (*passwd != '\0') {
+ update_keys(pkeys,pcrc_32_tab,(int)*passwd);
+ passwd++;
+ }
+}
+
+#define zdecode(pkeys,pcrc_32_tab,c) \
+ (update_keys(pkeys,pcrc_32_tab,c ^= decrypt_byte(pkeys,pcrc_32_tab)))
+
+#define zencode(pkeys,pcrc_32_tab,c,t) \
+ (t=decrypt_byte(pkeys,pcrc_32_tab), update_keys(pkeys,pcrc_32_tab,c), t^(c))
+
+#ifdef INCLUDECRYPTINGCODE_IFCRYPTALLOWED
+
+#define RAND_HEAD_LEN 12
+ /* "last resort" source for second part of crypt seed pattern */
+# ifndef ZCR_SEED2
+# define ZCR_SEED2 3141592654UL /* use PI as default pattern */
+# endif
+
+static int crypthead(passwd, buf, bufSize, pkeys, pcrc_32_tab, crcForCrypting)
+ const char *passwd; /* password string */
+ unsigned char *buf; /* where to write header */
+ int bufSize;
+ unsigned long* pkeys;
+ const unsigned long* pcrc_32_tab;
+ unsigned long crcForCrypting;
+{
+ int n; /* index in random header */
+ int t; /* temporary */
+ int c; /* random byte */
+ unsigned char header[RAND_HEAD_LEN-2]; /* random header */
+ static unsigned calls = 0; /* ensure different random header each time */
+
+ if (bufSize<RAND_HEAD_LEN)
+ return 0;
+
+ /* First generate RAND_HEAD_LEN-2 random bytes. We encrypt the
+ * output of rand() to get less predictability, since rand() is
+ * often poorly implemented.
+ */
+ if (++calls == 1)
+ {
+ srand((unsigned)(time(NULL) ^ ZCR_SEED2));
+ }
+ init_keys(passwd, pkeys, pcrc_32_tab);
+ for (n = 0; n < RAND_HEAD_LEN-2; n++)
+ {
+ c = (rand() >> 7) & 0xff;
+ header[n] = (unsigned char)zencode(pkeys, pcrc_32_tab, c, t);
+ }
+ /* Encrypt random header (last two bytes is high word of crc) */
+ init_keys(passwd, pkeys, pcrc_32_tab);
+ for (n = 0; n < RAND_HEAD_LEN-2; n++)
+ {
+ buf[n] = (unsigned char)zencode(pkeys, pcrc_32_tab, header[n], t);
+ }
+ buf[n++] = zencode(pkeys, pcrc_32_tab, (int)(crcForCrypting >> 16) & 0xff, t);
+ buf[n++] = zencode(pkeys, pcrc_32_tab, (int)(crcForCrypting >> 24) & 0xff, t);
+ return n;
+}
+
+#endif