Commit | Line | Data |
---|---|---|
0d7638ea | 1 | /* |
0f78b815 WD |
2 | * Routines to support checksumming of bytes. |
3 | * | |
4 | * Copyright (C) 1996 Andrew Tridgell | |
5 | * Copyright (C) 1996 Paul Mackerras | |
6 | * Copyright (C) 2004, 2005 Wayne Davison | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License as published by | |
10 | * the Free Software Foundation; either version 2 of the License, or | |
11 | * (at your option) any later version. | |
12 | * | |
13 | * This program is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | * GNU General Public License for more details. | |
17 | * | |
e7c67065 WD |
18 | * You should have received a copy of the GNU General Public License along |
19 | * with this program; if not, write to the Free Software Foundation, Inc., | |
20 | * 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. | |
0f78b815 | 21 | */ |
c627d613 AT |
22 | |
23 | #include "rsync.h" | |
24 | ||
ebb0a6f6 | 25 | int csum_length=2; /* initial value */ |
34ccb63e AT |
26 | |
27 | #define CSUM_CHUNK 64 | |
28 | ||
8ee6eb71 | 29 | extern int checksum_seed; |
d04e9c51 | 30 | extern int protocol_version; |
c627d613 AT |
31 | |
32 | /* | |
33 | a simple 32 bit checksum that can be upadted from either end | |
34 | (inspired by Mark Adler's Adler-32 checksum) | |
35 | */ | |
deb5bf1d | 36 | uint32 get_checksum1(char *buf1, int32 len) |
c627d613 | 37 | { |
deb5bf1d | 38 | int32 i; |
c627d613 | 39 | uint32 s1, s2; |
debb4505 | 40 | schar *buf = (schar *)buf1; |
c627d613 AT |
41 | |
42 | s1 = s2 = 0; | |
34ccb63e | 43 | for (i = 0; i < (len-4); i+=4) { |
0d7638ea | 44 | s2 += 4*(s1 + buf[i]) + 3*buf[i+1] + 2*buf[i+2] + buf[i+3] + |
1b01b295 | 45 | 10*CHAR_OFFSET; |
0d7638ea | 46 | s1 += (buf[i+0] + buf[i+1] + buf[i+2] + buf[i+3] + 4*CHAR_OFFSET); |
34ccb63e AT |
47 | } |
48 | for (; i < len; i++) { | |
1b01b295 | 49 | s1 += (buf[i]+CHAR_OFFSET); s2 += s1; |
c627d613 AT |
50 | } |
51 | return (s1 & 0xffff) + (s2 << 16); | |
52 | } | |
53 | ||
54 | ||
deb5bf1d | 55 | void get_checksum2(char *buf, int32 len, char *sum) |
c627d613 | 56 | { |
deb5bf1d | 57 | int32 i; |
8de330a3 | 58 | static char *buf1; |
deb5bf1d | 59 | static int32 len1; |
8de330a3 AT |
60 | struct mdfour m; |
61 | ||
62 | if (len > len1) { | |
deb5bf1d WD |
63 | if (buf1) |
64 | free(buf1); | |
58cadc86 | 65 | buf1 = new_array(char, len+4); |
8de330a3 | 66 | len1 = len; |
deb5bf1d WD |
67 | if (!buf1) |
68 | out_of_memory("get_checksum2"); | |
8de330a3 | 69 | } |
0d7638ea | 70 | |
8de330a3 | 71 | mdfour_begin(&m); |
0d7638ea | 72 | |
8de330a3 AT |
73 | memcpy(buf1,buf,len); |
74 | if (checksum_seed) { | |
75 | SIVAL(buf1,len,checksum_seed); | |
76 | len += 4; | |
77 | } | |
0d7638ea | 78 | |
8de330a3 | 79 | for(i = 0; i + CSUM_CHUNK <= len; i += CSUM_CHUNK) { |
7ae359c3 | 80 | mdfour_update(&m, (uchar *)(buf1+i), CSUM_CHUNK); |
8de330a3 | 81 | } |
fc1ae658 S |
82 | /* |
83 | * Prior to version 27 an incorrect MD4 checksum was computed | |
84 | * by failing to call mdfour_tail() for block sizes that | |
85 | * are multiples of 64. This is fixed by calling mdfour_update() | |
86 | * even when there are no more bytes. | |
87 | */ | |
d04e9c51 | 88 | if (len - i > 0 || protocol_version >= 27) { |
7ae359c3 | 89 | mdfour_update(&m, (uchar *)(buf1+i), (len-i)); |
8de330a3 | 90 | } |
0d7638ea | 91 | |
7ae359c3 | 92 | mdfour_result(&m, (uchar *)sum); |
c627d613 AT |
93 | } |
94 | ||
34ccb63e | 95 | |
bcacc18b | 96 | void file_checksum(char *fname,char *sum,OFF_T size) |
c627d613 | 97 | { |
8de330a3 AT |
98 | OFF_T i; |
99 | struct map_struct *buf; | |
100 | int fd; | |
101 | OFF_T len = size; | |
8de330a3 | 102 | struct mdfour m; |
0d7638ea | 103 | |
f855a7d0 | 104 | memset(sum,0,MD4_SUM_LENGTH); |
0d7638ea | 105 | |
8c9fd200 | 106 | fd = do_open(fname, O_RDONLY, 0); |
efa95a18 WD |
107 | if (fd == -1) |
108 | return; | |
0d7638ea | 109 | |
bd1a581b | 110 | buf = map_file(fd, size, MAX_MAP_SIZE, CSUM_CHUNK); |
0d7638ea | 111 | |
8de330a3 AT |
112 | mdfour_begin(&m); |
113 | ||
114 | for(i = 0; i + CSUM_CHUNK <= len; i += CSUM_CHUNK) { | |
afd8bdb9 WD |
115 | mdfour_update(&m, (uchar *)map_ptr(buf, i, CSUM_CHUNK), |
116 | CSUM_CHUNK); | |
8de330a3 AT |
117 | } |
118 | ||
afd8bdb9 | 119 | /* Prior to version 27 an incorrect MD4 checksum was computed |
fc1ae658 S |
120 | * by failing to call mdfour_tail() for block sizes that |
121 | * are multiples of 64. This is fixed by calling mdfour_update() | |
afd8bdb9 WD |
122 | * even when there are no more bytes. */ |
123 | if (len - i > 0 || protocol_version >= 27) | |
124 | mdfour_update(&m, (uchar *)map_ptr(buf, i, len-i), len-i); | |
8de330a3 | 125 | |
7ae359c3 | 126 | mdfour_result(&m, (uchar *)sum); |
8de330a3 AT |
127 | |
128 | close(fd); | |
129 | unmap_file(buf); | |
c627d613 | 130 | } |
34ccb63e AT |
131 | |
132 | ||
deb5bf1d | 133 | static int32 sumresidue; |
9e31c482 | 134 | static char sumrbuf[CSUM_CHUNK]; |
8de330a3 | 135 | static struct mdfour md; |
9e31c482 | 136 | |
ba582f75 | 137 | void sum_init(int seed) |
9e31c482 | 138 | { |
8de330a3 AT |
139 | char s[4]; |
140 | mdfour_begin(&md); | |
ba582f75 WD |
141 | sumresidue = 0; |
142 | SIVAL(s, 0, seed); | |
143 | sum_update(s, 4); | |
9e31c482 AT |
144 | } |
145 | ||
d37d8d7b MP |
146 | /** |
147 | * Feed data into an MD4 accumulator, md. The results may be | |
148 | * retrieved using sum_end(). md is used for different purposes at | |
149 | * different points during execution. | |
150 | * | |
151 | * @todo Perhaps get rid of md and just pass in the address each time. | |
152 | * Very slightly clearer and slower. | |
153 | **/ | |
deb5bf1d | 154 | void sum_update(char *p, int32 len) |
9e31c482 | 155 | { |
8de330a3 | 156 | if (len + sumresidue < CSUM_CHUNK) { |
deb5bf1d | 157 | memcpy(sumrbuf + sumresidue, p, len); |
8de330a3 AT |
158 | sumresidue += len; |
159 | return; | |
160 | } | |
161 | ||
162 | if (sumresidue) { | |
deb5bf1d WD |
163 | int32 i = CSUM_CHUNK - sumresidue; |
164 | memcpy(sumrbuf + sumresidue, p, i); | |
165 | mdfour_update(&md, (uchar *)sumrbuf, CSUM_CHUNK); | |
8de330a3 AT |
166 | len -= i; |
167 | p += i; | |
168 | } | |
169 | ||
deb5bf1d WD |
170 | while (len >= CSUM_CHUNK) { |
171 | mdfour_update(&md, (uchar *)p, CSUM_CHUNK); | |
172 | len -= CSUM_CHUNK; | |
173 | p += CSUM_CHUNK; | |
8de330a3 AT |
174 | } |
175 | ||
deb5bf1d WD |
176 | sumresidue = len; |
177 | if (sumresidue) | |
178 | memcpy(sumrbuf, p, sumresidue); | |
9e31c482 AT |
179 | } |
180 | ||
181 | void sum_end(char *sum) | |
182 | { | |
deb5bf1d | 183 | if (sumresidue || protocol_version >= 27) |
7ae359c3 | 184 | mdfour_update(&md, (uchar *)sumrbuf, sumresidue); |
9e31c482 | 185 | |
7ae359c3 | 186 | mdfour_result(&md, (uchar *)sum); |
9e31c482 | 187 | } |