1 #include "os.h"
2 #include <libsec.h>
3
4 /*
5 * rfc1321 requires that I include this. The code is new. The constants
6 * all come from the rfc (hence the copyright). We trade a table for the
7 * macros in rfc. The total size is a lot less. -- presotto
8 *
9 * Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
10 * rights reserved.
11 *
12 * License to copy and use this software is granted provided that it
13 * is identified as the "RSA Data Security, Inc. MD5 Message-Digest
14 * Algorithm" in all material mentioning or referencing this software
15 * or this function.
16 *
17 * License is also granted to make and use derivative works provided
18 * that such works are identified as "derived from the RSA Data
19 * Security, Inc. MD5 Message-Digest Algorithm" in all material
20 * mentioning or referencing the derived work.
21 *
22 * RSA Data Security, Inc. makes no representations concerning either
23 * the merchantability of this software or the suitability of this
24 * software forany particular purpose. It is provided "as is"
25 * without express or implied warranty of any kind.
26 * These notices must be retained in any copies of any part of this
27 * documentation and/or software.
28 */
29
30 static void encode(uchar*, u32int*, ulong);
31
32 extern void _md5block(uchar*, ulong, u32int*);
33
34 MD5state*
md5(uchar * p,ulong len,uchar * digest,MD5state * s)35 md5(uchar *p, ulong len, uchar *digest, MD5state *s)
36 {
37 u32int x[16];
38 uchar buf[128];
39 int i;
40 uchar *e;
41
42 if(s == nil){
43 s = malloc(sizeof(*s));
44 if(s == nil)
45 return nil;
46 memset(s, 0, sizeof(*s));
47 s->malloced = 1;
48 }
49
50 if(s->seeded == 0){
51 /* seed the state, these constants would look nicer big-endian */
52 s->state[0] = 0x67452301;
53 s->state[1] = 0xefcdab89;
54 s->state[2] = 0x98badcfe;
55 s->state[3] = 0x10325476;
56 s->seeded = 1;
57 }
58
59 /* fill out the partial 64 byte block from previous calls */
60 if(s->blen){
61 i = 64 - s->blen;
62 if(len < i)
63 i = len;
64 memmove(s->buf + s->blen, p, i);
65 len -= i;
66 s->blen += i;
67 p += i;
68 if(s->blen == 64){
69 _md5block(s->buf, s->blen, s->state);
70 s->len += s->blen;
71 s->blen = 0;
72 }
73 }
74
75 /* do 64 byte blocks */
76 i = len & ~0x3f;
77 if(i){
78 _md5block(p, i, s->state);
79 s->len += i;
80 len -= i;
81 p += i;
82 }
83
84 /* save the left overs if not last call */
85 if(digest == 0){
86 if(len){
87 memmove(s->buf, p, len);
88 s->blen += len;
89 }
90 return s;
91 }
92
93 /*
94 * this is the last time through, pad what's left with 0x80,
95 * 0's, and the input count to create a multiple of 64 bytes
96 */
97 if(s->blen){
98 p = s->buf;
99 len = s->blen;
100 } else {
101 memmove(buf, p, len);
102 p = buf;
103 }
104 s->len += len;
105 e = p + len;
106 if(len < 56)
107 i = 56 - len;
108 else
109 i = 120 - len;
110 memset(e, 0, i);
111 *e = 0x80;
112 len += i;
113
114 /* append the count */
115 x[0] = s->len<<3;
116 x[1] = s->len>>29;
117 encode(p+len, x, 8);
118
119 /* digest the last part */
120 _md5block(p, len+8, s->state);
121 s->len += len;
122
123 /* return result and free state */
124 encode(digest, s->state, MD5dlen);
125 if(s->malloced == 1)
126 free(s);
127 return nil;
128 }
129
130 /*
131 * encodes input (u32int) into output (uchar). Assumes len is
132 * a multiple of 4.
133 */
134 static void
encode(uchar * output,u32int * input,ulong len)135 encode(uchar *output, u32int *input, ulong len)
136 {
137 u32int x;
138 uchar *e;
139
140 for(e = output + len; output < e;) {
141 x = *input++;
142 *output++ = x;
143 *output++ = x >> 8;
144 *output++ = x >> 16;
145 *output++ = x >> 24;
146 }
147 }
148