/*

 * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996

 *	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: (1) source code distributions

 * retain the above copyright notice and this paragraph in its entirety, (2)

 * distributions including binary code include the above copyright notice and

 * this paragraph in its entirety in the documentation or other materials

 * provided with the distribution, and (3) all advertising materials mentioning

 * features or use of this software display the following acknowledgement:

 * ``This product includes software developed by the University of California,

 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of

 * the University nor the names of its contributors may be used to endorse

 * or promote products derived from this software without specific prior

 * written permission.

 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED

 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF

 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

 */

#ifdef HAVE_CONFIG_H

#include <config.h>

#endif

#include <sys/types.h>

#include <sys/time.h>

#include <sys/timeb.h>

#include <sys/file.h>

#include <sys/ioctl.h>

#include <sys/socket.h>

#include <net/if.h>

#include <net/nit.h>

#include <netinet/in.h>

#include <netinet/in_systm.h>

#include <netinet/ip.h>

#include <netinet/if_ether.h>

#include <netinet/ip_var.h>

#include <netinet/udp.h>

#include <netinet/udp_var.h>

#include <netinet/tcp.h>

#include <netinet/tcpip.h>

#include <ctype.h>

#include <errno.h>

#include <stdio.h>

#include "pcap-int.h"

#ifdef HAVE_OS_PROTO_H

#include "os-proto.h"

#endif

/*

 * The chunk size for NIT.  This is the amount of buffering

 * done for read calls.

 */

#define CHUNKSIZE (2*1024)

/*

 * The total buffer space used by NIT.

 */

#define BUFSPACE (4*CHUNKSIZE)

/* Forwards */

static int nit_setflags(int, int, int, char *);

/*

 * Private data for capturing on NIT devices.

 */

struct pcap_nit {

	struct pcap_stat stat;

};

static int

pcap_stats_nit(pcap_t *p, struct pcap_stat *ps)

{

	struct pcap_nit *pn = p->priv;

	/*

	 * "ps_recv" counts packets handed to the filter, not packets

	 * that passed the filter.  As filtering is done in userland,

	 * this does not include packets dropped because we ran out

	 * of buffer space.

	 *

	 * "ps_drop" presumably counts packets dropped by the socket

	 * because of flow control requirements or resource exhaustion;

	 * it doesn't count packets dropped by the interface driver.

	 * As filtering is done in userland, it counts packets regardless

	 * of whether they would've passed the filter.

	 *

	 * These statistics don't include packets not yet read from the

	 * kernel by libpcap or packets not yet read from libpcap by the

	 * application.

	 */

	*ps = pn->stat;

	return (0);

}

static int

pcap_read_nit(pcap_t *p, int cnt, pcap_handler callback, u_char *user)

{

	struct pcap_nit *pn = p->priv;

	register int cc, n;

	register u_char *bp, *cp, *ep;

	register struct nit_hdr *nh;

	register int caplen;

	cc = p->cc;

	if (cc == 0) {

		cc = read(p->fd, (char *)p->buffer, p->bufsize);

		if (cc < 0) {

			if (errno == EWOULDBLOCK)

				return (0);

			pcap_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),

			    errno, "pcap_read");

			return (-1);

		}

		bp = (u_char *)p->buffer;

	} else

		bp = p->bp;

	/*

	 * Loop through each packet.  The increment expression

	 * rounds up to the next int boundary past the end of

	 * the previous packet.

	 */

	n = 0;

	ep = bp + cc;

	while (bp < ep) {

		/*

		 * Has "pcap_breakloop()" been called?

		 * If so, return immediately - if we haven't read any

		 * packets, clear the flag and return -2 to indicate

		 * that we were told to break out of the loop, otherwise

		 * leave the flag set, so that the *next* call will break

		 * out of the loop without having read any packets, and

		 * return the number of packets we've processed so far.

		 */

		if (p->break_loop) {

			if (n == 0) {

				p->break_loop = 0;

				return (-2);

			} else {

				p->cc = ep - bp;

				p->bp = bp;

				return (n);

			}

		}

		nh = (struct nit_hdr *)bp;

		cp = bp + sizeof(*nh);

		switch (nh->nh_state) {

		case NIT_CATCH:

			break;

		case NIT_NOMBUF:

		case NIT_NOCLUSTER:

		case NIT_NOSPACE:

			pn->stat.ps_drop = nh->nh_dropped;

			continue;

		case NIT_SEQNO:

			continue;

		default:

			pcap_snprintf(p->errbuf, sizeof(p->errbuf),

			    "bad nit state %d", nh->nh_state);

			return (-1);

		}

		++pn->stat.ps_recv;

		bp += ((sizeof(struct nit_hdr) + nh->nh_datalen +

		    sizeof(int) - 1) & ~(sizeof(int) - 1));

		caplen = nh->nh_wirelen;

		if (caplen > p->snapshot)

			caplen = p->snapshot;

		if (bpf_filter(p->fcode.bf_insns, cp, nh->nh_wirelen, caplen)) {

			struct pcap_pkthdr h;

			h.ts = nh->nh_timestamp;

			h.len = nh->nh_wirelen;

			h.caplen = caplen;

			(*callback)(user, &h, cp);

			if (++n >= cnt && !PACKET_COUNT_IS_UNLIMITED(cnt)) {

				p->cc = ep - bp;

				p->bp = bp;

				return (n);

			}

		}

	}

	p->cc = 0;

	return (n);

}

static int

pcap_inject_nit(pcap_t *p, const void *buf, size_t size)

{

	struct sockaddr sa;

	int ret;

	memset(&sa, 0, sizeof(sa));

	strncpy(sa.sa_data, device, sizeof(sa.sa_data));

	ret = sendto(p->fd, buf, size, 0, &sa, sizeof(sa));

	if (ret == -1) {

		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,

		    errno, "send");

		return (-1);

	}

	return (ret);

}

static int

nit_setflags(pcap_t *p)

{

	struct nit_ioc nioc;

	memset(&nioc, 0, sizeof(nioc));

	nioc.nioc_typetomatch = NT_ALLTYPES;

	nioc.nioc_snaplen = p->snapshot;

	nioc.nioc_bufalign = sizeof(int);

	nioc.nioc_bufoffset = 0;

	if (p->opt.buffer_size != 0)

		nioc.nioc_bufspace = p->opt.buffer_size;

	else {

		/* Default buffer size */

		nioc.nioc_bufspace = BUFSPACE;

	}

	if (p->opt.immediate) {

		/*

		 * XXX - will this cause packets to be delivered immediately?

		 * XXX - given that this is for SunOS prior to 4.0, do

		 * we care?

		 */

		nioc.nioc_chunksize = 0;

	} else

		nioc.nioc_chunksize = CHUNKSIZE;

	if (p->opt.timeout != 0) {

		nioc.nioc_flags |= NF_TIMEOUT;

		nioc.nioc_timeout.tv_sec = p->opt.timeout / 1000;

		nioc.nioc_timeout.tv_usec = (p->opt.timeout * 1000) % 1000000;

	}

	if (p->opt.promisc)

		nioc.nioc_flags |= NF_PROMISC;

	if (ioctl(p->fd, SIOCSNIT, &nioc) < 0) {

		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,

		    errno, "SIOCSNIT");

		return (-1);

	}

	return (0);

}

static int

pcap_activate_nit(pcap_t *p)

{

	int fd;

	struct sockaddr_nit snit;

	if (p->opt.rfmon) {

		/*

		 * No monitor mode on SunOS 3.x or earlier (no

		 * Wi-Fi *devices* for the hardware that supported

		 * them!).

		 */

		return (PCAP_ERROR_RFMON_NOTSUP);

	}

	/*

	 * Turn a negative snapshot value (invalid), a snapshot value of

	 * 0 (unspecified), or a value bigger than the normal maximum

	 * value, into the maximum allowed value.

	 *

	 * If some application really *needs* a bigger snapshot

	 * length, we should just increase MAXIMUM_SNAPLEN.

	 */

	if (p->snapshot <= 0 || p->snapshot > MAXIMUM_SNAPLEN)

		p->snapshot = MAXIMUM_SNAPLEN;

	if (p->snapshot < 96)

		/*

		 * NIT requires a snapshot length of at least 96.

		 */

		p->snapshot = 96;

	memset(p, 0, sizeof(*p));

	p->fd = fd = socket(AF_NIT, SOCK_RAW, NITPROTO_RAW);

	if (fd < 0) {

		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,

		    errno, "socket");

		goto bad;

	}

	snit.snit_family = AF_NIT;

	(void)strncpy(snit.snit_ifname, p->opt.device, NITIFSIZ);

	if (bind(fd, (struct sockaddr *)&snit, sizeof(snit))) {

		/*

		 * XXX - there's probably a particular bind error that

		 * means "there's no such device" and a particular bind

		 * error that means "that device doesn't support NIT";

		 * they might be the same error, if they both end up

		 * meaning "NIT doesn't know about that device".

		 */

		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,

		    errno, "bind: %s", snit.snit_ifname);

		goto bad;

	}

	if (nit_setflags(p) < 0)

		goto bad;

	/*

	 * NIT supports only ethernets.

	 */

	p->linktype = DLT_EN10MB;

	p->bufsize = BUFSPACE;

	p->buffer = malloc(p->bufsize);

	if (p->buffer == NULL) {

		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,

		    errno, "malloc");

		goto bad;

	}

	/*

	 * "p->fd" is a socket, so "select()" should work on it.

	 */

	p->selectable_fd = p->fd;

	/*

	 * This is (presumably) a real Ethernet capture; give it a

	 * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so

	 * that an application can let you choose it, in case you're

	 * capturing DOCSIS traffic that a Cisco Cable Modem

	 * Termination System is putting out onto an Ethernet (it

	 * doesn't put an Ethernet header onto the wire, it puts raw

	 * DOCSIS frames out on the wire inside the low-level

	 * Ethernet framing).

	 */

	p->dlt_list = (u_int *) malloc(sizeof(u_int) * 2);

	/*

	 * If that fails, just leave the list empty.

	 */

	if (p->dlt_list != NULL) {

		p->dlt_list[0] = DLT_EN10MB;

		p->dlt_list[1] = DLT_DOCSIS;

		p->dlt_count = 2;

	}

	p->read_op = pcap_read_nit;

	p->inject_op = pcap_inject_nit;

	p->setfilter_op = install_bpf_program;	/* no kernel filtering */

	p->setdirection_op = NULL;	/* Not implemented. */

	p->set_datalink_op = NULL;	/* can't change data link type */

	p->getnonblock_op = pcap_getnonblock_fd;

	p->setnonblock_op = pcap_setnonblock_fd;

	p->stats_op = pcap_stats_nit;

	return (0);

 bad:

	pcap_cleanup_live_common(p);

	return (PCAP_ERROR);

}

pcap_t *

pcap_create_interface(const char *device _U_, char *ebuf)

{

	pcap_t *p;

	p = pcap_create_common(ebuf, sizeof (struct pcap_nit));

	if (p == NULL)

		return (NULL);

	p->activate_op = pcap_activate_nit;

	return (p);

}

/*

 * XXX - there's probably a particular bind error that means "that device

 * doesn't support NIT"; if so, we should try a bind and use that.

 */

static int

can_be_bound(const char *name _U_)

{

	return (1);

}

static int

get_if_flags(const char *name _U_, bpf_u_int32 *flags _U_, char *errbuf _U_)

{

	/*

	 * Nothing we can do.

	 * XXX - is there a way to find out whether an adapter has

	 * something plugged into it?

	 */

	return (0);

}

int

pcap_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf)

{

	return (pcap_findalldevs_interfaces(devlistp, errbuf, can_be_bound,

	    get_if_flags));

}

/*

 * Libpcap version string.

 */

const char *

pcap_lib_version(void)

{

	return (PCAP_VERSION_STRING);

}