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authorMark Adler <madler@alumni.caltech.edu>2011-09-09 23:25:17 -0700
committerMark Adler <madler@alumni.caltech.edu>2011-09-09 23:25:17 -0700
commitabf180a067223611620dd97dd5681df7c7fa7c9b (patch)
tree48ce6022aa1670380c098bd0abed2ac4aa1d9ca0 /contrib/minizip/crypt.h
parent9c3a5830218c4e7fff23b8fc4386269db77a03a9 (diff)
downloadzlib-1.2.3.tar.gz
zlib-1.2.3.tar.bz2
zlib-1.2.3.zip
zlib 1.2.3v1.2.3
Diffstat (limited to 'contrib/minizip/crypt.h')
-rw-r--r--contrib/minizip/crypt.h264
1 files changed, 132 insertions, 132 deletions
diff --git a/contrib/minizip/crypt.h b/contrib/minizip/crypt.h
index f14a628..622f4bc 100644
--- a/contrib/minizip/crypt.h
+++ b/contrib/minizip/crypt.h
@@ -1,132 +1,132 @@
1/* crypt.h -- base code for crypt/uncrypt ZIPfile 1/* crypt.h -- base code for crypt/uncrypt ZIPfile
2 2
3 3
4 Version 1.01e, February 12th, 2005 4 Version 1.01e, February 12th, 2005
5 5
6 Copyright (C) 1998-2005 Gilles Vollant 6 Copyright (C) 1998-2005 Gilles Vollant
7 7
8 This code is a modified version of crypting code in Infozip distribution 8 This code is a modified version of crypting code in Infozip distribution
9 9
10 The encryption/decryption parts of this source code (as opposed to the 10 The encryption/decryption parts of this source code (as opposed to the
11 non-echoing password parts) were originally written in Europe. The 11 non-echoing password parts) were originally written in Europe. The
12 whole source package can be freely distributed, including from the USA. 12 whole source package can be freely distributed, including from the USA.
13 (Prior to January 2000, re-export from the US was a violation of US law.) 13 (Prior to January 2000, re-export from the US was a violation of US law.)
14 14
15 This encryption code is a direct transcription of the algorithm from 15 This encryption code is a direct transcription of the algorithm from
16 Roger Schlafly, described by Phil Katz in the file appnote.txt. This 16 Roger Schlafly, described by Phil Katz in the file appnote.txt. This
17 file (appnote.txt) is distributed with the PKZIP program (even in the 17 file (appnote.txt) is distributed with the PKZIP program (even in the
18 version without encryption capabilities). 18 version without encryption capabilities).
19 19
20 If you don't need crypting in your application, just define symbols 20 If you don't need crypting in your application, just define symbols
21 NOCRYPT and NOUNCRYPT. 21 NOCRYPT and NOUNCRYPT.
22 22
23 This code support the "Traditional PKWARE Encryption". 23 This code support the "Traditional PKWARE Encryption".
24 24
25 The new AES encryption added on Zip format by Winzip (see the page 25 The new AES encryption added on Zip format by Winzip (see the page
26 http://www.winzip.com/aes_info.htm ) and PKWare PKZip 5.x Strong 26 http://www.winzip.com/aes_info.htm ) and PKWare PKZip 5.x Strong
27 Encryption is not supported. 27 Encryption is not supported.
28*/ 28*/
29 29
30#define CRC32(c, b) ((*(pcrc_32_tab+(((int)(c) ^ (b)) & 0xff))) ^ ((c) >> 8)) 30#define CRC32(c, b) ((*(pcrc_32_tab+(((int)(c) ^ (b)) & 0xff))) ^ ((c) >> 8))
31 31
32/*********************************************************************** 32/***********************************************************************
33 * Return the next byte in the pseudo-random sequence 33 * Return the next byte in the pseudo-random sequence
34 */ 34 */
35static int decrypt_byte(unsigned long* pkeys, const unsigned long* pcrc_32_tab) 35static int decrypt_byte(unsigned long* pkeys, const unsigned long* pcrc_32_tab)
36{ 36{
37 unsigned temp; /* POTENTIAL BUG: temp*(temp^1) may overflow in an 37 unsigned temp; /* POTENTIAL BUG: temp*(temp^1) may overflow in an
38 * unpredictable manner on 16-bit systems; not a problem 38 * unpredictable manner on 16-bit systems; not a problem
39 * with any known compiler so far, though */ 39 * with any known compiler so far, though */
40 40
41 temp = ((unsigned)(*(pkeys+2)) & 0xffff) | 2; 41 temp = ((unsigned)(*(pkeys+2)) & 0xffff) | 2;
42 return (int)(((temp * (temp ^ 1)) >> 8) & 0xff); 42 return (int)(((temp * (temp ^ 1)) >> 8) & 0xff);
43} 43}
44 44
45/*********************************************************************** 45/***********************************************************************
46 * Update the encryption keys with the next byte of plain text 46 * Update the encryption keys with the next byte of plain text
47 */ 47 */
48static int update_keys(unsigned long* pkeys,const unsigned long* pcrc_32_tab,int c) 48static int update_keys(unsigned long* pkeys,const unsigned long* pcrc_32_tab,int c)
49{ 49{
50 (*(pkeys+0)) = CRC32((*(pkeys+0)), c); 50 (*(pkeys+0)) = CRC32((*(pkeys+0)), c);
51 (*(pkeys+1)) += (*(pkeys+0)) & 0xff; 51 (*(pkeys+1)) += (*(pkeys+0)) & 0xff;
52 (*(pkeys+1)) = (*(pkeys+1)) * 134775813L + 1; 52 (*(pkeys+1)) = (*(pkeys+1)) * 134775813L + 1;
53 { 53 {
54 register int keyshift = (int)((*(pkeys+1)) >> 24); 54 register int keyshift = (int)((*(pkeys+1)) >> 24);
55 (*(pkeys+2)) = CRC32((*(pkeys+2)), keyshift); 55 (*(pkeys+2)) = CRC32((*(pkeys+2)), keyshift);
56 } 56 }
57 return c; 57 return c;
58} 58}
59 59
60 60
61/*********************************************************************** 61/***********************************************************************
62 * Initialize the encryption keys and the random header according to 62 * Initialize the encryption keys and the random header according to
63 * the given password. 63 * the given password.
64 */ 64 */
65static void init_keys(const char* passwd,unsigned long* pkeys,const unsigned long* pcrc_32_tab) 65static void init_keys(const char* passwd,unsigned long* pkeys,const unsigned long* pcrc_32_tab)
66{ 66{
67 *(pkeys+0) = 305419896L; 67 *(pkeys+0) = 305419896L;
68 *(pkeys+1) = 591751049L; 68 *(pkeys+1) = 591751049L;
69 *(pkeys+2) = 878082192L; 69 *(pkeys+2) = 878082192L;
70 while (*passwd != '\0') { 70 while (*passwd != '\0') {
71 update_keys(pkeys,pcrc_32_tab,(int)*passwd); 71 update_keys(pkeys,pcrc_32_tab,(int)*passwd);
72 passwd++; 72 passwd++;
73 } 73 }
74} 74}
75 75
76#define zdecode(pkeys,pcrc_32_tab,c) \ 76#define zdecode(pkeys,pcrc_32_tab,c) \
77 (update_keys(pkeys,pcrc_32_tab,c ^= decrypt_byte(pkeys,pcrc_32_tab))) 77 (update_keys(pkeys,pcrc_32_tab,c ^= decrypt_byte(pkeys,pcrc_32_tab)))
78 78
79#define zencode(pkeys,pcrc_32_tab,c,t) \ 79#define zencode(pkeys,pcrc_32_tab,c,t) \
80 (t=decrypt_byte(pkeys,pcrc_32_tab), update_keys(pkeys,pcrc_32_tab,c), t^(c)) 80 (t=decrypt_byte(pkeys,pcrc_32_tab), update_keys(pkeys,pcrc_32_tab,c), t^(c))
81 81
82#ifdef INCLUDECRYPTINGCODE_IFCRYPTALLOWED 82#ifdef INCLUDECRYPTINGCODE_IFCRYPTALLOWED
83 83
84#define RAND_HEAD_LEN 12 84#define RAND_HEAD_LEN 12
85 /* "last resort" source for second part of crypt seed pattern */ 85 /* "last resort" source for second part of crypt seed pattern */
86# ifndef ZCR_SEED2 86# ifndef ZCR_SEED2
87# define ZCR_SEED2 3141592654UL /* use PI as default pattern */ 87# define ZCR_SEED2 3141592654UL /* use PI as default pattern */
88# endif 88# endif
89 89
90static int crypthead(passwd, buf, bufSize, pkeys, pcrc_32_tab, crcForCrypting) 90static int crypthead(passwd, buf, bufSize, pkeys, pcrc_32_tab, crcForCrypting)
91 const char *passwd; /* password string */ 91 const char *passwd; /* password string */
92 unsigned char *buf; /* where to write header */ 92 unsigned char *buf; /* where to write header */
93 int bufSize; 93 int bufSize;
94 unsigned long* pkeys; 94 unsigned long* pkeys;
95 const unsigned long* pcrc_32_tab; 95 const unsigned long* pcrc_32_tab;
96 unsigned long crcForCrypting; 96 unsigned long crcForCrypting;
97{ 97{
98 int n; /* index in random header */ 98 int n; /* index in random header */
99 int t; /* temporary */ 99 int t; /* temporary */
100 int c; /* random byte */ 100 int c; /* random byte */
101 unsigned char header[RAND_HEAD_LEN-2]; /* random header */ 101 unsigned char header[RAND_HEAD_LEN-2]; /* random header */
102 static unsigned calls = 0; /* ensure different random header each time */ 102 static unsigned calls = 0; /* ensure different random header each time */
103 103
104 if (bufSize<RAND_HEAD_LEN) 104 if (bufSize<RAND_HEAD_LEN)
105 return 0; 105 return 0;
106 106
107 /* First generate RAND_HEAD_LEN-2 random bytes. We encrypt the 107 /* First generate RAND_HEAD_LEN-2 random bytes. We encrypt the
108 * output of rand() to get less predictability, since rand() is 108 * output of rand() to get less predictability, since rand() is
109 * often poorly implemented. 109 * often poorly implemented.
110 */ 110 */
111 if (++calls == 1) 111 if (++calls == 1)
112 { 112 {
113 srand((unsigned)(time(NULL) ^ ZCR_SEED2)); 113 srand((unsigned)(time(NULL) ^ ZCR_SEED2));
114 } 114 }
115 init_keys(passwd, pkeys, pcrc_32_tab); 115 init_keys(passwd, pkeys, pcrc_32_tab);
116 for (n = 0; n < RAND_HEAD_LEN-2; n++) 116 for (n = 0; n < RAND_HEAD_LEN-2; n++)
117 { 117 {
118 c = (rand() >> 7) & 0xff; 118 c = (rand() >> 7) & 0xff;
119 header[n] = (unsigned char)zencode(pkeys, pcrc_32_tab, c, t); 119 header[n] = (unsigned char)zencode(pkeys, pcrc_32_tab, c, t);
120 } 120 }
121 /* Encrypt random header (last two bytes is high word of crc) */ 121 /* Encrypt random header (last two bytes is high word of crc) */
122 init_keys(passwd, pkeys, pcrc_32_tab); 122 init_keys(passwd, pkeys, pcrc_32_tab);
123 for (n = 0; n < RAND_HEAD_LEN-2; n++) 123 for (n = 0; n < RAND_HEAD_LEN-2; n++)
124 { 124 {
125 buf[n] = (unsigned char)zencode(pkeys, pcrc_32_tab, header[n], t); 125 buf[n] = (unsigned char)zencode(pkeys, pcrc_32_tab, header[n], t);
126 } 126 }
127 buf[n++] = zencode(pkeys, pcrc_32_tab, (int)(crcForCrypting >> 16) & 0xff, t); 127 buf[n++] = zencode(pkeys, pcrc_32_tab, (int)(crcForCrypting >> 16) & 0xff, t);
128 buf[n++] = zencode(pkeys, pcrc_32_tab, (int)(crcForCrypting >> 24) & 0xff, t); 128 buf[n++] = zencode(pkeys, pcrc_32_tab, (int)(crcForCrypting >> 24) & 0xff, t);
129 return n; 129 return n;
130} 130}
131 131
132#endif 132#endif