/*
 * Copyright (c) 2002 Damien Miller.  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 ``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 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.
 */

#ifndef _SOFTFLOWD_H
#define _SOFTFLOWD_H
#include "common.h"
#include "sys-tree.h"
#include "freelist.h"
#include "treetype.h"
#include <pcap.h>
#ifdef ENABLE_PTHREAD
#include <pthread.h>
extern int use_thread;
#endif /* ENABLE_PTHREAD */
#ifdef ENABLE_NTOPNG
#include <zmq.h>
// The version field in NetFow and IPFIX headers is 16 bits unsiged int.
// If the version number is over 0x7fff0000, it is unique number in softflowd.
#define SOFTFLOWD_NF_VERSION_NTOPNG (0x7fff0001)
#define SOFTFLOWD_NF_VERSION_NTOPNG_STRING "ntopng"
struct ZMQ {
  void *context;
  void *socket;
};
#endif /* ENABLE_NTOPNG */

/* User to setuid to and directory to chroot to when we drop privs */
#ifndef PRIVDROP_USER
#define PRIVDROP_USER		"nobody"
#endif

#ifndef PRIVDROP_CHROOT_DIR
#define PRIVDROP_CHROOT_DIR	"/var/empty"
#endif
/*
 * Capture length for libpcap: Must fit the link layer header, plus 
 * a maximally sized ip/ipv6 header and most of a TCP header
 */
#define LIBPCAP_SNAPLEN_V4		96
#define LIBPCAP_SNAPLEN_V6		160

/*
 * Timeouts
 */
#define DEFAULT_TCP_TIMEOUT		3600
#define DEFAULT_TCP_RST_TIMEOUT		120
#define DEFAULT_TCP_FIN_TIMEOUT		300
#define DEFAULT_UDP_TIMEOUT		300
#define DEFAULT_ICMP_TIMEOUT		300
#define DEFAULT_GENERAL_TIMEOUT		3600
#define DEFAULT_MAXIMUM_LIFETIME	(3600*24*7)
#define DEFAULT_EXPIRY_INTERVAL		60

/*
 * Default maximum number of flow to track simultaneously 
 * 8192 corresponds to just under 1Mb of flow data
 */
#define DEFAULT_MAX_FLOWS	8192

#define NF_VERSION_IPFIX 10

/* Store a couple of statistics, maybe more in the future */
struct STATISTIC {
  double min, mean, max;
};

/* Flow tracking levels */
#define TRACK_FULL		1       /* src/dst/addr/port/proto/tos 6-tuple */
#define TRACK_IP_PROTO_PORT	2       /* src/dst/addr/port/proto 5-tuple */
#define TRACK_IP_PROTO		3       /* src/dst/proto 3-tuple */
#define TRACK_IP_ONLY		4       /* src/dst tuple */
#define TRACK_FULL_VLAN		5       /* src/dst/addr/port/proto/tos/vlanid 7-tuple */
#define TRACK_FULL_VLAN_ETHER	6       /* src/dst/addr/port/proto/tos/vlanid/src-mac/dst-mac 9-tuple */

#define SOFTFLOWD_MAX_DESTINATIONS 16

/*
 * This structure contains optional information carried by Option Data
 * Record.
 */
struct OPTION {
  uint32_t sample;
  pid_t meteringProcessId;
};

struct FLOWTRACKPARAMETERS {
  unsigned int num_flows;       /* # of active flows */
  unsigned int max_flows;       /* Max # of active flows */
  u_int64_t next_flow_seq;      /* Next flow ID */

  /* Stuff related to flow export */
  struct timeval system_boot_time;      /* SysUptime */
  int track_level;              /* See TRACK_* above */

  /* Flow timeouts */
  int tcp_timeout;              /* Open TCP connections */
  int tcp_rst_timeout;          /* TCP flows after RST */
  int tcp_fin_timeout;          /* TCP flows after bidi FIN */
  int udp_timeout;              /* UDP flows */
  int icmp_timeout;             /* ICMP flows */
  int general_timeout;          /* Everything else */
  int maximum_lifetime;         /* Maximum life for flows */
  int expiry_interval;          /* Interval between expiries */

  /* Statistics */
  u_int64_t total_packets;      /* # of good packets */
  u_int64_t non_sampled_packets;        /* # of not sampled packets */
  u_int64_t frag_packets;       /* # of fragmented packets */
  u_int64_t non_ip_packets;     /* # of not-IP packets */
  u_int64_t bad_packets;        /* # of bad packets */
  u_int64_t flows_expired;      /* # expired */
  u_int64_t flows_exported;     /* # of flows sent */
  u_int64_t flows_dropped;      /* # of flows dropped */
  u_int64_t flows_force_expired;        /* # of flows forced out */
  u_int64_t packets_sent;       /* # netflow packets sent */
  u_int64_t records_sent;       /* # netflow records sent */
  struct STATISTIC duration;    /* Flow duration */
  struct STATISTIC octets;      /* Bytes (bidir) */
  struct STATISTIC packets;     /* Packets (bidir) */

  /* Per protocol statistics */
  u_int64_t flows_pp[256];
  u_int64_t octets_pp[256];
  u_int64_t packets_pp[256];
  struct STATISTIC duration_pp[256];

  /* Timeout statistics */
  u_int64_t expired_general;
  u_int64_t expired_tcp;
  u_int64_t expired_tcp_rst;
  u_int64_t expired_tcp_fin;
  u_int64_t expired_udp;
  u_int64_t expired_icmp;
  u_int64_t expired_maxlife;
  u_int64_t expired_overbytes;
  u_int64_t expired_maxflows;
  u_int64_t expired_flush;

  /* Optional information */
  struct OPTION option;
  char time_format;
  u_int8_t bidirection;
  u_int8_t adjust_time;
  u_int8_t is_psamp;
  struct timeval last_packet_time;
};
/*
 * This structure is the root of the flow tracking system.
 * It holds the root of the tree of active flows and the head of the
 * tree of expiry events. It also collects miscellaneous statistics
 */
struct FLOWTRACK {
  /* The flows and their expiry events */
  FLOW_HEAD (FLOWS, FLOW) flows;        /* Top of flow tree */
  EXPIRY_HEAD (EXPIRIES, EXPIRY) expiries;      /* Top of expiries tree */

  struct freelist flow_freelist;        /* Freelist for flows */
  struct freelist expiry_freelist;      /* Freelist for expiry events */

  struct FLOWTRACKPARAMETERS param;
};

/*
 * This structure is an entry in the tree of flows that we are 
 * currently tracking. 
 *
 * Because flows are matched _bi-directionally_, they must be stored in
 * a canonical format: the numerically lowest address and port number must
 * be stored in the first address and port array slot respectively.
 */
struct FLOW {
  /* Housekeeping */
  struct EXPIRY *expiry;        /* Pointer to expiry record */
    FLOW_ENTRY (FLOW) trp;      /* Tree pointer */

  /* Per-flow statistics (all in _host_ byte order) */
  u_int64_t flow_seq;           /* Flow ID */
  struct timeval flow_start;    /* Time of creation */
  struct timeval flow_last;     /* Time of last traffic */

  /* Per-endpoint statistics (all in _host_ byte order) */
  u_int32_t octets[2];          /* Octets so far */
  u_int32_t packets[2];         /* Packets so far */

  /* Flow identity (all are in network byte order) */
  int af;                       /* Address family of flow */
  u_int32_t ip6_flowlabel[2];   /* IPv6 Flowlabel */
  union {
    struct in_addr v4;
    struct in6_addr v6;
  } addr[2];                    /* Endpoint addresses */
  u_int16_t port[2];            /* Endpoint ports */
  u_int8_t tcp_flags[2];        /* Cumulative OR of flags */
  u_int8_t tos[2];              /* Tos */
  u_int16_t vlanid[2];          /* vlanid */
  uint8_t ethermac[2][6];
  u_int8_t protocol;            /* Protocol */
};

/*
 * This is an entry in the tree of expiry events. The tree is used to 
 * avoid traversion the whole tree of active flows looking for ones to
 * expire. "expires_at" is the time at which the flow should be discarded,
 * or zero if it is scheduled for immediate disposal. 
 *
 * When a flow which hasn't been scheduled for immediate expiry registers 
 * traffic, it is deleted from its current position in the tree and 
 * re-inserted (subject to its updated timeout).
 *
 * Expiry scans operate by starting at the head of the tree and expiring
 * each entry with expires_at < now
 * 
 */
struct EXPIRY {
  EXPIRY_ENTRY (EXPIRY) trp;    /* Tree pointer */
  struct FLOW *flow;            /* pointer to flow */

  u_int32_t expires_at;         /* time_t */
  enum {
    R_GENERAL, R_TCP, R_TCP_RST, R_TCP_FIN, R_UDP, R_ICMP,
    R_MAXLIFE, R_OVERBYTES, R_OVERFLOWS, R_FLUSH
  } reason;
};

struct DESTINATION {
  char *arg;
  int sock;
  struct sockaddr_storage ss;
  socklen_t sslen;
  char hostname[NI_MAXHOST];
  char servname[NI_MAXSERV];
#ifdef ENABLE_NTOPNG
  struct ZMQ zmq;
#endif
};

/* Describes a location where we send NetFlow packets to */
struct NETFLOW_TARGET {
  int num_destinations;
  struct DESTINATION destinations[SOFTFLOWD_MAX_DESTINATIONS];
  const struct NETFLOW_SENDER *dialect;
  u_int8_t is_loadbalance;
};

struct SENDPARAMETER {
  struct FLOW **flows;
  int num_flows;
  struct NETFLOW_TARGET *target;
  u_int16_t ifidx;
  struct FLOWTRACKPARAMETERS *param;
  int verbose_flag;
};

/* Context for libpcap callback functions */
struct CB_CTXT {
  struct FLOWTRACK *ft;
  struct NETFLOW_TARGET *target;
  int linktype;
  int fatal;
  int want_v6;
};

/* Prototype for functions shared from softflowd.c */
u_int32_t timeval_sub_ms (const struct timeval *t1, const struct timeval *t2);
int send_multi_destinations (int num_destinations,
                             struct DESTINATION *destinations,
                             u_int8_t is_loadbalnce, u_int8_t * packet,
                             int size);
void flow_cb (u_char * user_data, const struct pcap_pkthdr *phdr,
              const u_char * pkt);

/* Prototypes for functions to send NetFlow packets, from netflow*.c */
int send_netflow_v1 (struct SENDPARAMETER sp);
int send_netflow_v5 (struct SENDPARAMETER sp);
#ifdef ENABLE_NTOPNG
/* Protypes for ntopng.c */
int connect_ntopng (const char *host, const char *port, struct ZMQ *zmq);
int send_ntopng (struct SENDPARAMETER sp);
#endif /* ENABLE_NTOPNG */

#endif /* _SOFTFLOWD_H */