/*-
 * Copyright (c) 2001, 2003, 2004 Lev Walkin <vlm@lionet.info>.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $Id: psrc.c,v 1.12 2005/07/07 05:54:53 vlm Exp $
 */

#include "ipcad.h"
#include "sf_lite.h"
#include "opt.h"

static int ifIndexes;	/* Ever-increasing interface name */

packet_source_t *
create_packet_source(char *ifname, int iflags, char *filter) {
	packet_source_t *ps;

	/*
	 * Create a new interface structure.
	 */
	ps = calloc(1, sizeof *ps);
	if(ps == NULL) return NULL;

	ps->fd = -1;	/* Packet source file descriptor */

	/*
	 * Fill-up the common parameters.
	 */
	strncpy( ps->ifName, ifname, sizeof(ps->ifName) );
	ps->ifName[sizeof(ps->ifName) - 1] = 0;
	ps->iflags = iflags;
	ps->custom_filter = filter;

	ps->avg_period = 300;   /* 5 minutes */
	ps->bytes_lp = -1;	/* Initial value */
	ps->packets_lp = -1;	/* Initial value */

	ps->state = PST_EMBRYONIC;


	/*
	 * Initialize packet source descriptors.
	 */
	if(strchr(ifname, '*')) {
		/*
		 * The interface does not exist, so it might be dynamic.
		 */
		fprintf(stderr, "[DYNAMIC] ");
		ps->process_ptr = process_dynamic;
		ps->print_stats = print_stats_dynamic;
		ps->iface_type = IFACE_DYNAMIC;
		ps->iface.dynamic.already_got = genhash_new(cmpf_string,
			hashf_string,
			NULL, (void (*)(void *))destroy_packet_source);
		if(ps->iface.dynamic.already_got == NULL)
			goto failure;
	} else if(strncasecmp(ifname, "ulog", 5) == 0) {
#ifdef	PSRC_ulog
		u_int32_t m = 0x80000000;
		char *p;
		int i;
		ps->process_ptr = process_ulog;
		ps->print_stats = print_stats_ulog;

		ps->iface_type = IFACE_ULOG;
		ps->iface.ulog.groupmask = strtoul(ps->custom_filter, NULL, 10);
		ps->iface.ulog.uName = p = calloc(1, 1 + 32 * (2 + 1) + 1);
		if(!p) goto failure;
		*p++ = 'u';	/* "u"log */
		for(i = 32; m; m >>= 1, i--) {
			assert(i >= 1);
			if(ps->iface.ulog.groupmask & m) {
				int ret = snprintf(p, 3, "%d,", i);
				assert(ret >= 1 && ret <= 3);
				p += ret;
			}
		}
		*(--p) = '\0';
		if(p == ps->iface.ulog.uName) {
			ps->iface.ulog.uName = NULL;
			free(p);
		}
#else	/* !PSRC_ulog */
		fprintf(stderr, "Linux ULOG is not supported\n");
		errno = EINVAL;
		goto failure;
#endif	/* PSRC_ulog */
	} else if(strncasecmp(ifname, "ipq", 4) == 0) {
#ifdef	PSRC_ipq
		ps->process_ptr = process_ipq;
		ps->print_stats = print_stats_ipq;

		ps->iface_type = IFACE_IPQ;
		ps->iface.ipq.peer.nl_family = AF_NETLINK;
#else	/* !PSRC_ipq */
		fprintf(stderr,
			"Linux IPQ interface is not supported\n");
		errno = EINVAL;
		goto failure;
#endif	/* PSRC_ipq */
	} else if(strncasecmp(ifname, "divert", 7) == 0
		|| strncasecmp(ifname, "tee", 4) == 0) {
#ifdef	IPPROTO_DIVERT
		ps->process_ptr = process_divert;
		ps->print_stats = print_stats_divert;

		if(strncasecmp(ifname, "d", 1) == 0)
			ps->iface_type = IFACE_DIVERT;
		else
			ps->iface_type = IFACE_TEE;
		ps->iface.divert.port = atoi(ps->custom_filter);
		ps->bufsize = 65536 + 4096;
		ps->buf = malloc(ps->bufsize);
		if(ps->buf == NULL) {
			ps->bufsize = 0;
			goto failure;
		}
#else	/* !IPPROTO_DIVERT */
		fprintf(stderr,
			"BSD divert(4)/tee interface is not supported\n");
		errno = EINVAL;
		goto failure;
#endif	/* IPPROTO_DIVERT */
	} else if(strcmp(ifname, "file") == 0) {
		ps->iface_type = IFACE_FILE;
		ps->process_ptr = process_file;
		ps->print_stats = print_stats_file;
		ps->iface.file.name = filter;
		ps->iface.file.dev = NULL;
	} else {
#ifdef	PSRC_bpf
		ps->process_ptr = process_bpf;
		ps->print_stats = print_stats_bpf;

		ps->iface_type = IFACE_BPF;
#endif	/* PSRC_bpf */
#ifdef	PSRC_pcap
		ps->process_ptr = process_pcap;
		ps->print_stats = print_stats_pcap;
		
    		ps->iface_type = IFACE_PCAP;
		ps->iface.pcap.dev = NULL;
		if(pthread_mutex_init(&ps->iface.pcap.dev_mutex, NULL) == -1)
			goto failure;
#endif	/* PSRC_pcap */
	}

	switch(ps->iface_type) {
	case IFACE_DYNAMIC:
		break;
#ifdef	IPPROTO_DIVERT
	case IFACE_DIVERT:
		/* Special interface index */
		ps->ifIndex = IFINDEX_DIVERT_MASK | ps->iface.divert.port;
		break;
	case IFACE_TEE:
		/* Special interface index */
		ps->ifIndex = IFINDEX_TEE_MASK | ps->iface.divert.port;
		break;
#endif	/* IPPROTO_DIVERT */
	default:
		ps->ifIndex = ++ifIndexes;
	}

	return ps;

failure:
	free(ps);
	return NULL;
}


int
init_packet_source(packet_source_t *ps, int retry_mode) {

	switch(ps->iface_type) {
	case IFACE_FILE:
		return init_packet_source_file(ps);
	case IFACE_DYNAMIC:
		return init_packet_source_dynamic(ps);
	case IFACE_ULOG:
		return init_packet_source_ulog(ps, retry_mode);
	case IFACE_IPQ:
		return init_packet_source_ipq(ps, retry_mode);
	case IFACE_DIVERT:
	case IFACE_TEE:
		return init_packet_source_divert(ps);
	default:
#ifdef  PSRC_bpf
		return init_packet_source_bpf(ps, retry_mode);
#elif   PSRC_pcap
		return init_packet_source_pcap(ps);
#else
#error  unknown packet source
#endif
	}
}

void
destroy_packet_source(packet_source_t *ps) {
	if(ps == NULL) return;

	if(ps->buf)
		free(ps->buf);

	if(ps->fd != -1)
		close(ps->fd);

	switch(ps->iface_type) {
	case IFACE_DYNAMIC:
		genhash_destroy(ps->iface.dynamic.already_got);
		break;
#ifdef	PSRC_pcap
	case IFACE_PCAP:
		if(ps->iface.pcap.dev)
			pcap_close(ps->iface.pcap.dev);
		pthread_mutex_destroy(&ps->iface.pcap.dev_mutex);
		break;
#endif
	default:
		break;
	}

	free(ps);
}

const char *
IFNameBySource(void *psrc) {
	packet_source_t *ps = psrc;
	if(ps) {
		switch(ps->iface_type) {
		case IFACE_FILE:
			return ps->iface.file.name;
#ifdef	PSRC_ulog
		case IFACE_ULOG:
			if(ps->iface.ulog.uName)
				return ps->iface.ulog.uName;
			/* Fall through */
#endif
		case IFACE_DIVERT:
		case IFACE_TEE:
			return ps->custom_filter;
		default:
			return ps->ifName;
		}
	} else {
		return "<?>";
	}
}