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
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
|
/*
* The author of this code is John Ioannidis, ji@tla.org,
* (except when noted otherwise).
*
* This code was written for BSD/OS in Athens, Greece, in November 1995.
*
* Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
* by Angelos D. Keromytis, kermit@forthnet.gr.
*
* Copyright (C) 1995, 1996, 1997 by John Ioannidis and Angelos D. Keromytis.
*
* Permission to use, copy, and modify this software without fee
* is hereby granted, provided that this entire notice is included in
* all copies of any software which is or includes a copy or
* modification of this software.
*
* THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTY. IN PARTICULAR, NEITHER AUTHOR MAKES ANY
* REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
* MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
* PURPOSE.
*/
/*
* Authentication Header Processing
* Per RFC1826 (Atkinson, 1995)
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <machine/cpu.h>
#include <net/if.h>
#include <net/route.h>
#include <net/netisr.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/in_pcb.h>
#include <netinet/in_var.h>
#include <netinet/ip_var.h>
#include <netinet/ip_icmp.h>
#include <sys/socketvar.h>
#include <net/raw_cb.h>
#include <net/encap.h>
#include <netinet/ip_ipsp.h>
#include <netinet/ip_ah.h>
/*
* ah_input gets called when we receive an packet with an AH.
*/
void
ah_input(register struct mbuf *m, int iphlen)
{
struct ip *ipo;
struct ah *ahp;
struct tdb *tdbp;
struct ifqueue *ifq = NULL;
int s;
/*
* Strip IP options, if any.
*/
if (iphlen > sizeof (struct ip))
{
ip_stripoptions(m, (struct mbuf *)0);
iphlen = sizeof (struct ip);
}
/*
* Make sure that at least the fixed part of the AH header is
* in the first mbuf.
*/
ipo = mtod(m, struct ip *);
if (m->m_len < iphlen + AH_FLENGTH)
{
if ((m = m_pullup(m, iphlen + AH_FLENGTH)) == 0)
{
ahstat.ahs_hdrops++;
return;
}
ipo = mtod(m, struct ip *);
}
ahp = (struct ah *)((caddr_t)ipo + iphlen);
/*
* Find tunnel control block and (indirectly) call the appropriate
* tranform routine. The resulting mbuf chain is a valid
* IP packet ready to go through input processing.
*/
tdbp = gettdb(ahp->ah_spi, ipo->ip_dst);
if (tdbp == NULL)
{
#ifdef ENCDEBUG
if (encdebug)
printf("ah_input: no tdb for spi=%x\n", ahp->ah_spi);
#endif ENCDEBUG
m_freem(m);
ahstat.ahs_notdb++;
return;
}
if (tdbp->tdb_xform == NULL)
{
#ifdef ENCDEBUG
if (encdebug)
printf("ah_input: no xform for spi=%x\n", ahp->ah_spi);
#endif ENCDEBUG
m_freem(m);
ahstat.ahs_noxform++;
return;
}
m->m_pkthdr.rcvif = tdbp->tdb_rcvif;
m = (*(tdbp->tdb_xform->xf_input))(m, tdbp);
if (m == NULL)
{
ahstat.ahs_badkcr++;
return;
}
/*
* Interface pointer is already in first mbuf; chop off the
* `outer' header and reschedule.
*/
ifq = &ipintrq;
s = splimp(); /* isn't it already? */
if (IF_QFULL(ifq))
{
IF_DROP(ifq);
m_freem(m);
ahstat.ahs_qfull++;
splx(s);
return;
}
IF_ENQUEUE(ifq, m);
schednetisr(NETISR_IP);
splx(s);
return;
}
|
