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
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
|
/*
* Rest in pieces - RIP protocol
*
* Copyright (c) 1999 Pavel Machek <pavel@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#define LOCAL_DEBUG
#include <string.h>
#include <stdlib.h>
#include "nest/bird.h"
#include "nest/iface.h"
#include "nest/protocol.h"
#include "nest/route.h"
#include "lib/socket.h"
#include "lib/resource.h"
#include "lib/lists.h"
#include "lib/timer.h"
#include "lib/md5.h"
#include "rip.h"
#define P ((struct rip_proto *) p)
#define P_CF ((struct rip_proto_config *)p->cf)
#define PACKETLEN(num) (num * sizeof(struct rip_block) + sizeof(struct rip_packet_heading))
/* 1 == failed, 0 == ok */
int
rip_incoming_authentication( struct proto *p, struct rip_block_auth *block, struct rip_packet *packet, int num )
{
DBG( "Incoming authentication: " );
switch (block->authtype) { /* Authentication type */
case AT_PLAINTEXT:
DBG( "Plaintext passwd" );
if (!P_CF->passwords) {
log( L_AUTH "no passwords set and password authentication came\n" );
return 1;
}
if (strncmp( (char *) (&block->packetlen), P_CF->passwords->password, 16)) {
log( L_AUTH "Passwd authentication failed!\n" );
return 1;
}
return 0;
case AT_MD5:
DBG( "md5 password" );
{
struct password_item *head;
struct rip_md5_tail *tail;
if (block->packetlen != PACKETLEN(num)) {
log( L_ERR "packetlen in md5 does not match computed value\n" );
return 1;
}
tail = (struct rip_md5_tail *) ((char *) packet + (block->packetlen - sizeof(struct rip_block_auth)));
head = P_CF->passwords;
while (head) {
/* FIXME: should check serial numbers, somehow */
DBG( "time, " );
if ((head->from > now) || (head->to < now))
goto skip;
DBG( "check, " );
if (head->id == block->keyid) {
struct MD5Context ctxt;
char md5sum_packet[16];
char md5sum_computed[16];
memcpy(md5sum_packet, tail->md5, 16);
password_strncpy(tail->md5, head->password, 16);
MD5Init(&ctxt);
MD5Update(&ctxt, (char *) packet, block->packetlen );
MD5Final(md5sum_computed, &ctxt);
if (memcmp(md5sum_packet, md5sum_computed, 16))
return 1;
return 0;
}
skip:
head = head->next;
}
return 1;
}
}
return 0;
}
void
rip_outgoing_authentication( struct proto *p, struct rip_block_auth *block, struct rip_packet *packet, int num )
{
struct password_item *passwd = get_best_password( P_CF->passwords, 0 );
DBG( "Outgoing authentication: " );
if (!passwd) {
log( L_ERR "no suitable password found for authentication\n" );
return;
}
block->authtype = P_CF->authtype;
block->mustbeFFFF = 0xffff;
switch (P_CF->authtype) {
case AT_PLAINTEXT:
password_strncpy( (char *) (&block->packetlen), passwd->password, 16);
return;
case AT_MD5:
{
struct rip_md5_tail *tail;
struct MD5Context ctxt;
static int sequence = 0;
if (num > PACKET_MD5_MAX)
bug( "we can not add MD5 authentication to this long packet\n" );
block->keyid = passwd->id;
block->authlen = 20;
block->seq = sequence++;
block->zero0 = 0;
block->zero1 = 1;
block->packetlen = PACKETLEN(num);
tail = (struct rip_md5_tail *) ((char *) packet + (block->packetlen - sizeof(struct rip_block_auth)));
tail->mustbeFFFF = 0xffff;
tail->mustbe0001 = 0x0001;
password_strncpy( (char *) (&tail->md5), passwd->password, 16 );
MD5Init(&ctxt);
MD5Update(&ctxt, (char *) packet, block->packetlen );
MD5Final((char *) (&tail->md5), &ctxt);
return;
}
}
}
|
