diff options
Diffstat (limited to 'zlib/contrib/minizip/crypt.h')
-rw-r--r-- | zlib/contrib/minizip/crypt.h | 131 |
1 files changed, 0 insertions, 131 deletions
diff --git a/zlib/contrib/minizip/crypt.h b/zlib/contrib/minizip/crypt.h deleted file mode 100644 index 1e9e820..0000000 --- a/zlib/contrib/minizip/crypt.h +++ /dev/null @@ -1,131 +0,0 @@ -/* 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 z_crc_t* 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 z_crc_t* 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 z_crc_t* 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(const char* passwd, /* password string */ - unsigned char* buf, /* where to write header */ - int bufSize, - unsigned long* pkeys, - const z_crc_t* 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++] = (unsigned char)zencode(pkeys, pcrc_32_tab, (int)(crcForCrypting >> 16) & 0xff, t); - buf[n++] = (unsigned char)zencode(pkeys, pcrc_32_tab, (int)(crcForCrypting >> 24) & 0xff, t); - return n; -} - -#endif |