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
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
|
/*
* Stanford Enetfilter subroutines for tcpdump
*
* Based on the MERIT NNstat etherifrt.c and the Ultrix pcap-pf.c
* subroutines.
*
* Rayan Zachariassen, CA*Net
*/
#include <sys/types.h>
#include <sys/time.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <net/if.h>
#include <net/bpf.h>
#include <net/enet.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <stdio.h>
#include <errno.h>
#include "interface.h"
struct packet_header {
#ifdef IBMRTPC
struct LengthWords length;
struct tap_header tap;
#endif /* IBMRTPC */
u_char packet[8]
};
extern int errno;
#define BUFSPACE (4*1024)
/* Forwards */
static void efReadError(int, char *);
void
readloop(int cnt, int if_fd, struct bpf_program *fp, printfunc printit)
{
#ifdef IBMRTPC
register struct packet_header *ph;
register u_char *bp;
register int inc;
#else /* !IBMRTPC */
static struct timeval tv = { 0 };
#endif /* IBMRTPC */
register int cc, caplen;
register struct bpf_insn *fcode = fp->bf_insns;
union {
struct packet_header hdr;
u_char p[BUFSPACE];
u_short s;
} buf;
while (1) {
if ((cc = read(if_fd, (char *)buf.p, sizeof(buf))) < 0)
efReadError(if_fd, "reader");
#ifdef IBMRTPC
/*
* Loop through each packet.
*/
bp = buf.p;
while (cc > 0) {
ph = (struct packet_header *)bp;
caplen = ph->tap.th_wirelen > snaplen ? snaplen : ph->tap
.th_wirelen ;
if (bpf_filter(fcode, (char *)ph->packet,
ph->tap.th_wirelen, caplen)) {
if (cnt >= 0 && --cnt < 0)
goto out;
(*printit)((char *)ph->packet,
(struct timeval *)ph->tap.th_timestamp,
ph->tap.th_wirelen, caplen);
}
inc = ph->length.PacketOffset;
cc -= inc;
bp += inc;
}
#else /* !IBMRTPC */
caplen = cc > snaplen ? snaplen : cc ;
if (bpf_filter(fcode, buf.hdr.packet, cc, caplen)) {
if (cnt >= 0 && --cnt < 0)
goto out;
(*printit)(buf.hdr.packet, &tv, cc, caplen);
}
#endif /* IBMRTPC */
}
out:
wrapup(if_fd);
}
/* Call ONLY if read() has returned an error on packet filter */
static void
efReadError(int fid, char *msg)
{
if (errno == EINVAL) { /* read MAXINT bytes already! */
if (lseek(fid, 0, 0) < 0) {
perror("tcpdump: efReadError/lseek");
exit(-1);
}
else
return;
}
else {
(void) fprintf(stderr, "tcpdump: ");
perror(msg);
exit(-1);
}
}
void
wrapup(int fd)
{
#ifdef IBMRTPC
struct enstats es;
if (ioctl(fd, EIOSTATS, &es) == -1) {
perror("tcpdump: enet ioctl EIOSTATS error");
exit(-1);
}
fprintf(stderr, "%d packets queued", es.enStat_Rcnt);
if (es.enStat_Rdrops > 0)
fprintf(stderr, ", %d dropped", es.enStat_Rdrops);
if (es.enStat_Reads > 0)
fprintf(stderr, ", %d tcpdump %s", es.enStat_Reads,
es.enStat_Reads > 1 ? "reads" : "read");
if (es.enStat_MaxRead > 1)
fprintf(stderr, ", %d packets in largest read",
es.enStat_MaxRead);
putc('\n', stderr);
#endif /* IBMRTPC */
close(fd);
}
int
initdevice(char *device, int pflag, int *linktype)
{
struct eniocb ctl;
struct enfilter filter;
u_int maxwaiting;
int if_fd;
#ifdef IBMRTPC
GETENETDEVICE(0, O_RDONLY, &if_fd);
#else /* !IBMRTPC */
if_fd = open("/dev/enet", O_RDONLY, 0);
#endif /* IBMRTPC */
if (if_fd == -1) {
perror("tcpdump: enet open error");
error(
"your system may not be properly configured; see \"man enet(4)\"");
exit(-1);
}
/* Get operating parameters. */
if (ioctl(if_fd, EIOCGETP, (char *)&ctl) == -1) {
perror("tcpdump: enet ioctl EIOCGETP error");
exit(-1);
}
/* Set operating parameters. */
#ifdef IBMRTPC
ctl.en_rtout = 1 * ctl.en_hz;
ctl.en_tr_etherhead = 1;
ctl.en_tap_network = 1;
ctl.en_multi_packet = 1;
ctl.en_maxlen = BUFSPACE;
#else /* !IBMRTPC */
ctl.en_rtout = 64; /* randomly picked value for HZ */
#endif /* IBMRTPC */
if (ioctl(if_fd, EIOCSETP, &ctl) == -1) {
perror("tcpdump: enet ioctl EIOCSETP error");
exit(-1);
}
/* Flush the receive queue, since we've changed
the operating parameters and we otherwise might
receive data without headers. */
if (ioctl(if_fd, EIOCFLUSH) == -1) {
perror("tcpdump: enet ioctl EIOCFLUSH error");
exit(-1);
}
/* Set the receive queue depth to its maximum. */
maxwaiting = ctl.en_maxwaiting;
if (ioctl(if_fd, EIOCSETW, &maxwaiting) == -1) {
perror("tcpdump: enet ioctl EIOCSETW error");
exit(-1);
}
#ifdef IBMRTPC
/* Clear statistics. */
if (ioctl(if_fd, EIOCLRSTAT, 0) == -1) {
perror("tcpdump: enet ioctl EIOCLRSTAT error");
exit(-1);
}
#endif /* IBMRTPC */
/* Set the filter (accept all packets). */
filter.enf_Priority = 3;
filter.enf_FilterLen = 0;
if (ioctl(if_fd, EIOCSETF, &filter) == -1) {
perror("tcpdump: enet ioctl EIOCSETF error");
exit(-1);
}
/*
* "enetfilter" supports only ethernets.
*/
*linktype = DLT_EN10MB;
return(if_fd);
}
|
