1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
|
/*
* Copyright (c) 1995 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the Network Research
* Group at Lawrence Berkeley National Laboratory.
* 4. Neither the name of the University nor of the Laboratory may be used
* to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
static const char rcsid[] =
"@(#) $Header: /cs/research/mice/starship/src/local/CVS_repository/vic/crypt-dull.cc,v 1.1.1.1 1998/02/18 18:03:22 ucacsva Exp $ (LBL)";
#include "crypt.h"
#include "inet.h"
#include "rtp.h"
/*
* A simple XOR data scrambler. This is module is provided for test
* purposes and to illustrate the extensibility of the encryption interface.
*
* This algorithm is trivial to crack using an obvious plaintext
* attack. It will only protect against accidental eavesdropping.
*/
class CryptDull : public Crypt {
public:
CryptDull();
~CryptDull();
virtual int install_key(const u_int8_t* key);
virtual u_char* Encrypt(const u_char* in, int& len);
virtual int Decrypt(const u_char* in, int len, u_char* out);
protected:
void crypt(const u_int32_t* in, u_int32_t* out, int nw);
u_int32_t key_;
u_char* wrkbuf_;
};
static class CryptDullMatcher : public Matcher {
public:
CryptDullMatcher() : Matcher("crypt") {}
TclObject* match(const char* id) {
if (strcmp(id, "DULL/data") == 0 ||
strcmp(id, "DULL/ctrl") == 0)
return (new CryptDull);
else
return (0);
}
} crypt_dull_matcher;
CryptDull::CryptDull()
{
/* enough extra space for padding and RTCP 4-byte random header */
wrkbuf_ = new u_char[RTP_MTU + 8 + 4];
}
CryptDull::~CryptDull()
{
delete wrkbuf_;
}
int CryptDull::install_key(const u_int8_t* key)
{
/* net order */
key_ = *(u_int32_t*)key;
return (0);
}
void CryptDull::crypt(const u_int32_t* in, u_int32_t* out, int nw)
{
u_int32_t k = key_;
for (int i = 0; i < nw; ++i)
out[i] = in[i] ^ k;
}
u_char* CryptDull::Encrypt(const u_char* in, int& len)
{
/*
* assume input is word-aligned and we can read
* past end to next longword boundary
*/
crypt((const u_int32_t*)in, (u_int32_t*)wrkbuf_, (len + 3) >> 2);
return (wrkbuf_);
}
int CryptDull::Decrypt(const u_char* in, int len, u_char* out)
{
/*
* assume input/output is word-aligned and we can read/write
* past end to next longword boundary
*/
crypt((const u_int32_t*)in, (u_int32_t*)out, (len + 3) >> 2);
return (len);
}
|
