diff options
Diffstat (limited to 'src/zlib/crypt.h')
-rw-r--r-- | src/zlib/crypt.h | 264 |
1 files changed, 132 insertions, 132 deletions
diff --git a/src/zlib/crypt.h b/src/zlib/crypt.h index f14a628b4..622f4bc2e 100644 --- a/src/zlib/crypt.h +++ b/src/zlib/crypt.h @@ -1,132 +1,132 @@ -/* 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
+/* 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 |