Subversion Repositories planix.SVN

Rev

Rev 33 | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
26 7u83 1 
#include "os.h"
2 
#include <libsec.h>
3 
 
4 
/*
5 
 * Define by analogy with desCBCencrypt;  AES modes are not standardized yet.
6 
 * Because of the way that non-multiple-of-16 buffers are handled,
7 
 * the decryptor must be fed buffers of the same size as the encryptor.
8 
 */
9 
void
10 
aesCBCencrypt(uchar *p, int len, AESstate *s)
11 
{
12 
	uchar *ip, *eip;
13 
 
14 
	if(((p-(uchar*)0) & 3) == 0){
15 
		for(; len >= AESbsize; len -= AESbsize){
16 
			ip = s->ivec;
17 
			((u32int*)ip)[0] ^= ((u32int*)p)[0];
18 
			((u32int*)ip)[1] ^= ((u32int*)p)[1];
19 
			((u32int*)ip)[2] ^= ((u32int*)p)[2];
20 
			((u32int*)ip)[3] ^= ((u32int*)p)[3];
21 
 
22 
			aes_encrypt(s->ekey, s->rounds, ip, ip);
23 
 
24 
			((u32int*)p)[0] = ((u32int*)ip)[0];
25 
			((u32int*)p)[1] = ((u32int*)ip)[1];
26 
			((u32int*)p)[2] = ((u32int*)ip)[2];
27 
			((u32int*)p)[3] = ((u32int*)ip)[3];
28 
			p += AESbsize;
29 
		}
30 
	} else {
31 
		for(; len >= AESbsize; len -= AESbsize){
32 
			ip = s->ivec;
33 
			for(eip = ip+AESbsize; ip < eip; )
34 
				*ip++ ^= *p++;
35 
			aes_encrypt(s->ekey, s->rounds, s->ivec, s->ivec);
36 
			memmove(p - AESbsize, s->ivec, AESbsize);
37 
		}
38 
	}
39 
 
40 
	if(len > 0){
41 
		ip = s->ivec;
42 
		aes_encrypt(s->ekey, s->rounds, ip, ip);
43 
		for(eip = ip+len; ip < eip; )
44 
			*p++ ^= *ip++;
45 
	}
46 
}
47 
 
48 
void
49 
aesCBCdecrypt(uchar *p, int len, AESstate *s)
50 
{
51 
	uchar *ip, *eip, *tp;
52 
	u32int t[4];
53 
 
54 
	if(((p-(uchar*)0) & 3) == 0){
55 
		for(; len >= AESbsize; len -= AESbsize){
56 
			t[0] = ((u32int*)p)[0];
57 
			t[1] = ((u32int*)p)[1];
58 
			t[2] = ((u32int*)p)[2];
59 
			t[3] = ((u32int*)p)[3];
60 
 
61 
			aes_decrypt(s->dkey, s->rounds, p, p);
62 
 
63 
			ip = s->ivec;
64 
			((u32int*)p)[0] ^= ((u32int*)ip)[0];
65 
			((u32int*)p)[1] ^= ((u32int*)ip)[1];
66 
			((u32int*)p)[2] ^= ((u32int*)ip)[2];
67 
			((u32int*)p)[3] ^= ((u32int*)ip)[3];
68 
			p += AESbsize;
69 
 
70 
			((u32int*)ip)[0] = t[0];
71 
			((u32int*)ip)[1] = t[1];
72 
			((u32int*)ip)[2] = t[2];
73 
			((u32int*)ip)[3] = t[3];
74 
		}
75 
	} else {
76 
		for(; len >= AESbsize; len -= AESbsize){
77 
			tp = (uchar*)t;
78 
			memmove(tp, p, AESbsize);
79 
			aes_decrypt(s->dkey, s->rounds, p, p);
80 
			ip = s->ivec;
81 
			for(eip = ip+AESbsize; ip < eip; ){
82 
				*p++ ^= *ip;
83 
				*ip++ = *tp++;
84 
			}
85 
		}
86 
	}
87 
 
88 
	if(len > 0){
89 
		ip = s->ivec;
90 
		aes_encrypt(s->ekey, s->rounds, ip, ip);
91 
		for(eip = ip+len; ip < eip; )
92 
			*p++ ^= *ip++;
93 
	}
94 
}