1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * Copyright (C) 1993-2001 by Darren Reed.
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * See the IPFILTER.LICENCE file for details on licencing.
5*0Sstevel@tonic-gate  *
6*0Sstevel@tonic-gate  * $Id: ipft_pc.c,v 1.9 2003/02/16 02:32:36 darrenr Exp $
7*0Sstevel@tonic-gate  */
8*0Sstevel@tonic-gate #include "ipf.h"
9*0Sstevel@tonic-gate #include "pcap-ipf.h"
10*0Sstevel@tonic-gate #include "bpf-ipf.h"
11*0Sstevel@tonic-gate #include "ipt.h"
12*0Sstevel@tonic-gate 
13*0Sstevel@tonic-gate #if !defined(lint)
14*0Sstevel@tonic-gate static const char rcsid[] = "@(#)$Id: ipft_pc.c,v 1.9 2003/02/16 02:32:36 darrenr Exp $";
15*0Sstevel@tonic-gate #endif
16*0Sstevel@tonic-gate 
17*0Sstevel@tonic-gate struct	llc	{
18*0Sstevel@tonic-gate 	int	lc_type;
19*0Sstevel@tonic-gate 	int	lc_sz;	/* LLC header length */
20*0Sstevel@tonic-gate 	int	lc_to;	/* LLC Type offset */
21*0Sstevel@tonic-gate 	int	lc_tl;	/* LLC Type length */
22*0Sstevel@tonic-gate };
23*0Sstevel@tonic-gate 
24*0Sstevel@tonic-gate /*
25*0Sstevel@tonic-gate  * While many of these maybe the same, some do have different header formats
26*0Sstevel@tonic-gate  * which make this useful.
27*0Sstevel@tonic-gate  */
28*0Sstevel@tonic-gate 
29*0Sstevel@tonic-gate static	struct	llc	llcs[] = {
30*0Sstevel@tonic-gate 	{ DLT_NULL, 0, 0, 0 },
31*0Sstevel@tonic-gate 	{ DLT_EN10MB, 14, 12, 2 },
32*0Sstevel@tonic-gate 	{ DLT_EN3MB, 0, 0, 0 },
33*0Sstevel@tonic-gate 	{ DLT_AX25, 0, 0, 0 },
34*0Sstevel@tonic-gate 	{ DLT_PRONET, 0, 0, 0 },
35*0Sstevel@tonic-gate 	{ DLT_CHAOS, 0, 0, 0 },
36*0Sstevel@tonic-gate 	{ DLT_IEEE802, 0, 0, 0 },
37*0Sstevel@tonic-gate 	{ DLT_ARCNET, 0, 0, 0 },
38*0Sstevel@tonic-gate 	{ DLT_SLIP, 0, 0, 0 },
39*0Sstevel@tonic-gate 	{ DLT_PPP, 0, 0, 0 },
40*0Sstevel@tonic-gate 	{ DLT_FDDI, 0, 0, 0 },
41*0Sstevel@tonic-gate #ifdef DLT_ATMRFC1483
42*0Sstevel@tonic-gate 	{ DLT_ATMRFC1483, 0, 0, 0 },
43*0Sstevel@tonic-gate #endif
44*0Sstevel@tonic-gate 	{ DLT_RAW, 0, 0, 0 },
45*0Sstevel@tonic-gate #ifdef	DLT_ENC
46*0Sstevel@tonic-gate 	{ DLT_ENC, 0, 0, 0 },
47*0Sstevel@tonic-gate #endif
48*0Sstevel@tonic-gate #ifdef	DLT_SLIP_BSDOS
49*0Sstevel@tonic-gate 	{ DLT_SLIP_BSDOS, 0, 0, 0 },
50*0Sstevel@tonic-gate #endif
51*0Sstevel@tonic-gate #ifdef	DLT_PPP_BSDOS
52*0Sstevel@tonic-gate 	{ DLT_PPP_BSDOS, 0, 0, 0 },
53*0Sstevel@tonic-gate #endif
54*0Sstevel@tonic-gate #ifdef	DLT_HIPPI
55*0Sstevel@tonic-gate 	{ DLT_HIPPI, 0, 0, 0 },
56*0Sstevel@tonic-gate #endif
57*0Sstevel@tonic-gate #ifdef	DLT_HDLC
58*0Sstevel@tonic-gate 	{ DLT_HDLC, 0, 0, 0 },
59*0Sstevel@tonic-gate #endif
60*0Sstevel@tonic-gate #ifdef	DLT_PPP_SERIAL
61*0Sstevel@tonic-gate 	{ DLT_PPP_SERIAL, 4, 4, 0 },
62*0Sstevel@tonic-gate #endif
63*0Sstevel@tonic-gate #ifdef	DLT_PPP_ETHER
64*0Sstevel@tonic-gate 	{ DLT_PPP_ETHER, 8, 8, 0 },
65*0Sstevel@tonic-gate #endif
66*0Sstevel@tonic-gate #ifdef	DLT_ECONET
67*0Sstevel@tonic-gate 	{ DLT_ECONET, 0, 0, 0 },
68*0Sstevel@tonic-gate #endif
69*0Sstevel@tonic-gate 	{ -1, -1, -1, -1 }
70*0Sstevel@tonic-gate };
71*0Sstevel@tonic-gate 
72*0Sstevel@tonic-gate static	int	pcap_open __P((char *));
73*0Sstevel@tonic-gate static	int	pcap_close __P((void));
74*0Sstevel@tonic-gate static	int	pcap_readip __P((char *, int, char **, int *));
75*0Sstevel@tonic-gate static	void	swap_hdr __P((pcaphdr_t *));
76*0Sstevel@tonic-gate static	int	pcap_read_rec __P((struct pcap_pkthdr *));
77*0Sstevel@tonic-gate 
78*0Sstevel@tonic-gate static	int	pfd = -1, s_type = -1, swapped = 0;
79*0Sstevel@tonic-gate static	struct llc	*llcp = NULL;
80*0Sstevel@tonic-gate 
81*0Sstevel@tonic-gate struct	ipread	pcap = { pcap_open, pcap_close, pcap_readip, 0 };
82*0Sstevel@tonic-gate 
83*0Sstevel@tonic-gate #define	SWAPLONG(y)	\
84*0Sstevel@tonic-gate 	((((y)&0xff)<<24) | (((y)&0xff00)<<8) | (((y)&0xff0000)>>8) | (((y)>>24)&0xff))
85*0Sstevel@tonic-gate #define	SWAPSHORT(y)	\
86*0Sstevel@tonic-gate 	( (((y)&0xff)<<8) | (((y)&0xff00)>>8) )
87*0Sstevel@tonic-gate 
88*0Sstevel@tonic-gate static	void	swap_hdr(p)
89*0Sstevel@tonic-gate pcaphdr_t	*p;
90*0Sstevel@tonic-gate {
91*0Sstevel@tonic-gate 	p->pc_v_maj = SWAPSHORT(p->pc_v_maj);
92*0Sstevel@tonic-gate 	p->pc_v_min = SWAPSHORT(p->pc_v_min);
93*0Sstevel@tonic-gate 	p->pc_zone = SWAPLONG(p->pc_zone);
94*0Sstevel@tonic-gate 	p->pc_sigfigs = SWAPLONG(p->pc_sigfigs);
95*0Sstevel@tonic-gate 	p->pc_slen = SWAPLONG(p->pc_slen);
96*0Sstevel@tonic-gate 	p->pc_type = SWAPLONG(p->pc_type);
97*0Sstevel@tonic-gate }
98*0Sstevel@tonic-gate 
99*0Sstevel@tonic-gate static	int	pcap_open(fname)
100*0Sstevel@tonic-gate char	*fname;
101*0Sstevel@tonic-gate {
102*0Sstevel@tonic-gate 	pcaphdr_t ph;
103*0Sstevel@tonic-gate 	int fd, i;
104*0Sstevel@tonic-gate 
105*0Sstevel@tonic-gate 	if (pfd != -1)
106*0Sstevel@tonic-gate 		return pfd;
107*0Sstevel@tonic-gate 
108*0Sstevel@tonic-gate 	if (!strcmp(fname, "-"))
109*0Sstevel@tonic-gate 		fd = 0;
110*0Sstevel@tonic-gate 	else if ((fd = open(fname, O_RDONLY)) == -1)
111*0Sstevel@tonic-gate 		return -1;
112*0Sstevel@tonic-gate 
113*0Sstevel@tonic-gate 	if (read(fd, (char *)&ph, sizeof(ph)) != sizeof(ph))
114*0Sstevel@tonic-gate 		return -2;
115*0Sstevel@tonic-gate 
116*0Sstevel@tonic-gate 	if (ph.pc_id != TCPDUMP_MAGIC) {
117*0Sstevel@tonic-gate 		if (SWAPLONG(ph.pc_id) != TCPDUMP_MAGIC) {
118*0Sstevel@tonic-gate 			(void) close(fd);
119*0Sstevel@tonic-gate 			return -2;
120*0Sstevel@tonic-gate 		}
121*0Sstevel@tonic-gate 		swapped = 1;
122*0Sstevel@tonic-gate 		swap_hdr(&ph);
123*0Sstevel@tonic-gate 	}
124*0Sstevel@tonic-gate 
125*0Sstevel@tonic-gate 	if (ph.pc_v_maj != PCAP_VERSION_MAJ) {
126*0Sstevel@tonic-gate 		(void) close(fd);
127*0Sstevel@tonic-gate 		return -2;
128*0Sstevel@tonic-gate 	}
129*0Sstevel@tonic-gate 
130*0Sstevel@tonic-gate 	for (i = 0; llcs[i].lc_type != -1; i++)
131*0Sstevel@tonic-gate 		if (llcs[i].lc_type == ph.pc_type) {
132*0Sstevel@tonic-gate 			llcp = llcs + i;
133*0Sstevel@tonic-gate 			break;
134*0Sstevel@tonic-gate 		}
135*0Sstevel@tonic-gate 
136*0Sstevel@tonic-gate 	if (llcp == NULL) {
137*0Sstevel@tonic-gate 		(void) close(fd);
138*0Sstevel@tonic-gate 		return -2;
139*0Sstevel@tonic-gate 	}
140*0Sstevel@tonic-gate 
141*0Sstevel@tonic-gate 	pfd = fd;
142*0Sstevel@tonic-gate 	s_type = ph.pc_type;
143*0Sstevel@tonic-gate 	printf("opened pcap file %s:\n", fname);
144*0Sstevel@tonic-gate 	printf("\tid: %08x version: %d.%d type: %d snap %d\n",
145*0Sstevel@tonic-gate 		ph.pc_id, ph.pc_v_maj, ph.pc_v_min, ph.pc_type, ph.pc_slen);
146*0Sstevel@tonic-gate 
147*0Sstevel@tonic-gate 	return fd;
148*0Sstevel@tonic-gate }
149*0Sstevel@tonic-gate 
150*0Sstevel@tonic-gate 
151*0Sstevel@tonic-gate static	int	pcap_close()
152*0Sstevel@tonic-gate {
153*0Sstevel@tonic-gate 	return close(pfd);
154*0Sstevel@tonic-gate }
155*0Sstevel@tonic-gate 
156*0Sstevel@tonic-gate 
157*0Sstevel@tonic-gate /*
158*0Sstevel@tonic-gate  * read in the header (and validate) which should be the first record
159*0Sstevel@tonic-gate  * in a pcap file.
160*0Sstevel@tonic-gate  */
161*0Sstevel@tonic-gate static	int	pcap_read_rec(rec)
162*0Sstevel@tonic-gate struct	pcap_pkthdr *rec;
163*0Sstevel@tonic-gate {
164*0Sstevel@tonic-gate 	int	n, p;
165*0Sstevel@tonic-gate 
166*0Sstevel@tonic-gate 	if (read(pfd, (char *)rec, sizeof(*rec)) != sizeof(*rec))
167*0Sstevel@tonic-gate 		return -2;
168*0Sstevel@tonic-gate 
169*0Sstevel@tonic-gate 	if (swapped) {
170*0Sstevel@tonic-gate 		rec->ph_clen = SWAPLONG(rec->ph_clen);
171*0Sstevel@tonic-gate 		rec->ph_len = SWAPLONG(rec->ph_len);
172*0Sstevel@tonic-gate 		rec->ph_ts.tv_sec = SWAPLONG(rec->ph_ts.tv_sec);
173*0Sstevel@tonic-gate 		rec->ph_ts.tv_usec = SWAPLONG(rec->ph_ts.tv_usec);
174*0Sstevel@tonic-gate 	}
175*0Sstevel@tonic-gate 	p = rec->ph_clen;
176*0Sstevel@tonic-gate 	n = MIN(p, rec->ph_len);
177*0Sstevel@tonic-gate 	if (!n || n < 0)
178*0Sstevel@tonic-gate 		return -3;
179*0Sstevel@tonic-gate 
180*0Sstevel@tonic-gate 	return p;
181*0Sstevel@tonic-gate }
182*0Sstevel@tonic-gate 
183*0Sstevel@tonic-gate 
184*0Sstevel@tonic-gate #ifdef	notyet
185*0Sstevel@tonic-gate /*
186*0Sstevel@tonic-gate  * read an entire pcap packet record.  only the data part is copied into
187*0Sstevel@tonic-gate  * the available buffer, with the number of bytes copied returned.
188*0Sstevel@tonic-gate  */
189*0Sstevel@tonic-gate static	int	pcap_read(buf, cnt)
190*0Sstevel@tonic-gate char	*buf;
191*0Sstevel@tonic-gate int	cnt;
192*0Sstevel@tonic-gate {
193*0Sstevel@tonic-gate 	struct	pcap_pkthdr rec;
194*0Sstevel@tonic-gate 	static	char	*bufp = NULL;
195*0Sstevel@tonic-gate 	int	i, n;
196*0Sstevel@tonic-gate 
197*0Sstevel@tonic-gate 	if ((i = pcap_read_rec(&rec)) <= 0)
198*0Sstevel@tonic-gate 		return i;
199*0Sstevel@tonic-gate 
200*0Sstevel@tonic-gate 	if (!bufp)
201*0Sstevel@tonic-gate 		bufp = malloc(i);
202*0Sstevel@tonic-gate 	else
203*0Sstevel@tonic-gate 		bufp = realloc(bufp, i);
204*0Sstevel@tonic-gate 
205*0Sstevel@tonic-gate 	if (read(pfd, bufp, i) != i)
206*0Sstevel@tonic-gate 		return -2;
207*0Sstevel@tonic-gate 
208*0Sstevel@tonic-gate 	n = MIN(i, cnt);
209*0Sstevel@tonic-gate 	bcopy(bufp, buf, n);
210*0Sstevel@tonic-gate 	return n;
211*0Sstevel@tonic-gate }
212*0Sstevel@tonic-gate #endif
213*0Sstevel@tonic-gate 
214*0Sstevel@tonic-gate 
215*0Sstevel@tonic-gate /*
216*0Sstevel@tonic-gate  * return only an IP packet read into buf
217*0Sstevel@tonic-gate  */
218*0Sstevel@tonic-gate static	int	pcap_readip(buf, cnt, ifn, dir)
219*0Sstevel@tonic-gate char	*buf, **ifn;
220*0Sstevel@tonic-gate int	cnt, *dir;
221*0Sstevel@tonic-gate {
222*0Sstevel@tonic-gate 	static	char	*bufp = NULL;
223*0Sstevel@tonic-gate 	struct	pcap_pkthdr rec;
224*0Sstevel@tonic-gate 	struct	llc	*l;
225*0Sstevel@tonic-gate 	char	*s, ty[4];
226*0Sstevel@tonic-gate 	int	i, n;
227*0Sstevel@tonic-gate 
228*0Sstevel@tonic-gate 	l = llcp;
229*0Sstevel@tonic-gate 
230*0Sstevel@tonic-gate 	/* do { */
231*0Sstevel@tonic-gate 		if ((i = pcap_read_rec(&rec)) <= 0)
232*0Sstevel@tonic-gate 			return i;
233*0Sstevel@tonic-gate 
234*0Sstevel@tonic-gate 		if (!bufp)
235*0Sstevel@tonic-gate 			bufp = malloc(i);
236*0Sstevel@tonic-gate 		else
237*0Sstevel@tonic-gate 			bufp = realloc(bufp, i);
238*0Sstevel@tonic-gate 		s = bufp;
239*0Sstevel@tonic-gate 
240*0Sstevel@tonic-gate 		if (read(pfd, s, i) != i)
241*0Sstevel@tonic-gate 			return -2;
242*0Sstevel@tonic-gate 
243*0Sstevel@tonic-gate 		i -= l->lc_sz;
244*0Sstevel@tonic-gate 		s += l->lc_to;
245*0Sstevel@tonic-gate 		bcopy(s, ty, l->lc_tl);
246*0Sstevel@tonic-gate 		s += l->lc_tl;
247*0Sstevel@tonic-gate 	/* } while (ty[0] != 0x8 && ty[1] != 0); */
248*0Sstevel@tonic-gate 	n = MIN(i, cnt);
249*0Sstevel@tonic-gate 	bcopy(s, buf, n);
250*0Sstevel@tonic-gate 	return n;
251*0Sstevel@tonic-gate }
252