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Diffstat (limited to 'hge/ZLIB/crypt.h')
-rw-r--r-- | hge/ZLIB/crypt.h | 136 |
1 files changed, 0 insertions, 136 deletions
diff --git a/hge/ZLIB/crypt.h b/hge/ZLIB/crypt.h deleted file mode 100644 index c01e587..0000000 --- a/hge/ZLIB/crypt.h +++ /dev/null @@ -1,136 +0,0 @@ -/* crypt.h -- base code for crypt/uncrypt ZIPfile - - -Version 1.01, May 8th, 2004 - -Copyright (C) 1998-2004 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 |