n2n/include/n2n_typedefs.h

/**
 * (C) 2007-20 - ntop.org and contributors
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not see see <http://www.gnu.org/licenses/>
 *
 */

#ifndef _N2N_TYPEDEFS_H_
#define _N2N_TYPEDEFS_H_



typedef uint8_t n2n_community_t[N2N_COMMUNITY_SIZE];
typedef uint8_t n2n_mac_t[N2N_MAC_SIZE];
typedef uint8_t n2n_cookie_t[N2N_COOKIE_SIZE];
typedef uint8_t n2n_desc_t[N2N_DESC_SIZE];
typedef char    n2n_sock_str_t[N2N_SOCKBUF_SIZE];       /* tracing string buffer */

#if defined(_MSC_VER) || defined(__MINGW32__)
#include "getopt.h"

 /* Other Win environments are expected to support stdint.h */

 /* stdint.h typedefs (C99) (not present in Visual Studio) */
typedef unsigned int uint32_t;
typedef unsigned short uint16_t;
typedef unsigned char uint8_t;

/* sys/types.h typedefs (not present in Visual Studio) */
typedef unsigned int u_int32_t;
typedef unsigned short u_int16_t;
typedef unsigned char u_int8_t;

#ifndef __MINGW32__
typedef int ssize_t;
#endif

typedef unsigned long in_addr_t;

#include "n2n_win32.h"

#endif /* #if defined(_MSC_VER) || defined(__MINGW32__) */



#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__)
#include <machine/endian.h>
#endif

#ifdef __OpenBSD__
#include <endian.h>
#define __BYTE_ORDER BYTE_ORDER
#if BYTE_ORDER == LITTLE_ENDIAN
#ifndef __LITTLE_ENDIAN__
#define __LITTLE_ENDIAN__
#endif /* __LITTLE_ENDIAN__ */
#else
#define __BIG_ENDIAN__
#endif/* BYTE_ORDER */
#endif/* __OPENBSD__ */


#if __BYTE_ORDER == __LITTLE_ENDIAN
#ifndef __LITTLE_ENDIAN__
#define __LITTLE_ENDIAN__
#endif
#else
#ifndef __BIG_ENDIAN__
#define __BIG_ENDIAN__
#endif
#endif

#ifdef WIN32
#ifndef __LITTLE_ENDIAN__
#define __LITTLE_ENDIAN__ 1
#endif
#endif

#if !(defined(__LITTLE_ENDIAN__) || defined(__BIG_ENDIAN__))
#if defined(__mips__)
#undef __LITTLE_ENDIAN__
#undef __LITTLE_ENDIAN
#define __BIG_ENDIAN__
#endif

/* Everything else */
#if (defined(__BYTE_ORDER__) && defined(__ORDER_LITTLE_ENDIAN__))
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
#define __LITTLE_ENDIAN__
#else
#define __BIG_ENDIAN__
#endif
#endif

#endif

/* *************************************** */

#ifdef __GNUC__
#define PACK_STRUCT __attribute__((__packed__))
#else
#define PACK_STRUCT
#endif

#if defined(_MSC_VER) || defined(__MINGW32__)
#pragma pack(push,1)
#endif

#define ETH_ADDR_LEN 6

struct ether_hdr {
  uint8_t  dhost[ETH_ADDR_LEN];
  uint8_t  shost[ETH_ADDR_LEN];
  uint16_t type;                /* higher layer protocol encapsulated */
} PACK_STRUCT;

typedef struct ether_hdr ether_hdr_t;


struct n2n_iphdr {
#if defined(__LITTLE_ENDIAN__)
    u_int8_t ihl:4, version:4;
#elif defined(__BIG_ENDIAN__)
    u_int8_t version:4, ihl:4;
#else
# error "Byte order must be defined"
#endif
    u_int8_t tos;
    u_int16_t tot_len;
    u_int16_t id;
    u_int16_t frag_off;
    u_int8_t ttl;
    u_int8_t protocol;
    u_int16_t check;
    u_int32_t saddr;
    u_int32_t daddr;
} PACK_STRUCT;

struct n2n_tcphdr {
  u_int16_t source;
  u_int16_t dest;
  u_int32_t seq;
  u_int32_t ack_seq;
#if defined(__LITTLE_ENDIAN__)
  u_int16_t res1:4, doff:4, fin:1, syn:1, rst:1, psh:1, ack:1, urg:1, ece:1, cwr:1;
#elif defined(__BIG_ENDIAN__)
  u_int16_t doff:4, res1:4, cwr:1, ece:1, urg:1, ack:1, psh:1, rst:1, syn:1, fin:1;
#else
# error "Byte order must be defined"
#endif
  u_int16_t window;
  u_int16_t check;
  u_int16_t urg_ptr;
} PACK_STRUCT;

struct n2n_udphdr {
  u_int16_t source;
  u_int16_t dest;
  u_int16_t len;
  u_int16_t check;
} PACK_STRUCT;

#if defined(_MSC_VER) || defined(__MINGW32__)
#pragma pack(pop)
#endif


typedef struct port_range {
  uint16_t start_port; // range contain 'start_port' self
  uint16_t end_port;   // range contain 'end_port' self
} port_range_t;

typedef struct filter_rule_key {
  in_addr_t        src_net_cidr;
  uint8_t          src_net_bit_len;
  port_range_t     src_port_range;
  in_addr_t        dst_net_cidr;
  uint8_t          dst_net_bit_len;
  port_range_t     dst_port_range;
  uint8_t          bool_tcp_configured;
  uint8_t          bool_udp_configured;
  uint8_t          bool_icmp_configured;
} filter_rule_key_t;

typedef struct filter_rule {
  filter_rule_key_t key;

  uint8_t             bool_accept_icmp;
  uint8_t             bool_accept_udp;
  uint8_t             bool_accept_tcp;

  UT_hash_handle hh;         /* makes this structure hashable */
} filter_rule_t;


#ifndef WIN32
typedef struct tuntap_dev {
  int             fd;
  int             if_idx;
  n2n_mac_t       mac_addr;
  uint32_t        ip_addr;
  uint32_t        device_mask;
  uint16_t        mtu;
  char            dev_name[N2N_IFNAMSIZ];
} tuntap_dev;

#define SOCKET int
#endif /* #ifndef WIN32 */

/** Uncomment this to enable the MTU check, then try to ssh to generate a fragmented packet. */
/** NOTE: see doc/MTU.md for an explanation on the 1400 value */
//#define MTU_ASSERT_VALUE 1400

/** Common type used to hold stringified IP addresses. */
typedef char ipstr_t[32];

/** Common type used to hold stringified MAC addresses. */
#define N2N_MACSTR_SIZE 32
typedef char macstr_t[N2N_MACSTR_SIZE];
typedef char dec_ip_str_t[N2N_NETMASK_STR_SIZE];
typedef char dec_ip_bit_str_t[N2N_NETMASK_STR_SIZE + 4];

typedef struct speck_context_t he_context_t;
typedef char n2n_sn_name_t[N2N_EDGE_SN_HOST_SIZE];

typedef enum n2n_pc {
  n2n_ping =               0,   /* Not used */
  n2n_register =           1,   /* Register edge to edge */
  n2n_deregister =         2,   /* Deregister this edge */
  n2n_packet =             3,   /* PACKET data content */
  n2n_register_ack =       4,   /* ACK of a registration from edge to edge */
  n2n_register_super =     5,   /* Register edge to supernode */
  n2n_unregister_super =   6,   /* Deregister edge from supernode */
  n2n_register_super_ack = 7,   /* ACK from supernode to edge */
  n2n_register_super_nak = 8,   /* NAK from supernode to edge - registration refused */
  n2n_federation =         9,   /* Not used by edge */
  n2n_peer_info =          10,  /* Send info on a peer from sn to edge */
  n2n_query_peer =         11   /* ask supernode for info on a peer */
} n2n_pc_t;

#define N2N_FLAGS_OPTIONS               0x0080
#define N2N_FLAGS_SOCKET                0x0040
#define N2N_FLAGS_FROM_SUPERNODE        0x0020

/* The bits in flag that are the packet type */
#define N2N_FLAGS_TYPE_MASK             0x001f  /* 0 - 31 */
#define N2N_FLAGS_BITS_MASK             0xffe0

#define IPV4_SIZE                       4
#define IPV6_SIZE                       16


#define N2N_AUTH_TOKEN_SIZE             32      /* bytes */


#define N2N_EUNKNOWN                    -1
#define N2N_ENOTIMPL                    -2
#define N2N_EINVAL                      -3
#define N2N_ENOSPACE                    -4

typedef struct n2n_ip_subnet {
  uint32_t            net_addr;       /* Host order IP address. */
  uint8_t             net_bitlen;     /* Subnet prefix. */
} n2n_ip_subnet_t;


typedef struct n2n_sock {
  uint8_t     family;         /* AF_INET or AF_INET6; or 0 if invalid */
  uint16_t    port;           /* host order */
  union {
    uint8_t     v6[IPV6_SIZE];  /* byte sequence */
    uint8_t     v4[IPV4_SIZE];  /* byte sequence */
  } addr;
} n2n_sock_t;

typedef enum {
  n2n_auth_none =      0,
  n2n_auth_simple_id = 1
} n2n_auth_scheme_t;

typedef enum {
  update_edge_no_change =   0,
  update_edge_sock_change = 1,
  update_edge_new_sn =      2,
  update_edge_auth_fail =  -1
} update_edge_ret_value_t;

typedef struct n2n_auth {
  uint16_t    scheme;                         /* What kind of auth */
  uint16_t    toksize;                        /* Size of auth token */
  uint8_t     token[N2N_AUTH_TOKEN_SIZE];     /* Auth data interpreted based on scheme */
} n2n_auth_t;

typedef struct n2n_common {
  /* NOTE: wire representation is different! */
  /* int                 version; */

  uint8_t             ttl;
  uint8_t             pc;
  uint16_t            flags;
  n2n_community_t     community;
} n2n_common_t;

typedef struct n2n_REGISTER {
  n2n_cookie_t         cookie;         /**< Link REGISTER and REGISTER_ACK */
  n2n_mac_t            srcMac;         /**< MAC of registering party */
  n2n_mac_t            dstMac;         /**< MAC of target edge */
  n2n_sock_t           sock;           /**< REVISIT: unused? */
  n2n_ip_subnet_t      dev_addr;       /**< IP address of the tuntap adapter. */
  n2n_desc_t           dev_desc;       /**< Hint description correlated with the edge */
} n2n_REGISTER_t;

typedef struct n2n_REGISTER_ACK {
  n2n_cookie_t         cookie;         /**< Return cookie from REGISTER */
  n2n_mac_t            srcMac;         /**< MAC of acknowledging party (supernode or edge) */
  n2n_mac_t            dstMac;         /**< Reflected MAC of registering edge from REGISTER */
  n2n_sock_t           sock;           /**< Supernode's view of edge socket (IP Addr, port) */
} n2n_REGISTER_ACK_t;

typedef struct n2n_PACKET {
  n2n_mac_t           srcMac;
  n2n_mac_t           dstMac;
  n2n_sock_t          sock;
  uint8_t             transform;
  uint8_t             compression;
} n2n_PACKET_t;

/* Linked with n2n_register_super in n2n_pc_t. Only from edge to supernode. */
typedef struct n2n_REGISTER_SUPER {
  n2n_cookie_t        cookie;         /**< Link REGISTER_SUPER and REGISTER_SUPER_ACK */
  n2n_mac_t           edgeMac;        /**< MAC to register with edge sending socket */
  n2n_sock_t          sock;           /**< Sending socket associated with srcMac */
  n2n_ip_subnet_t     dev_addr;       /**< IP address of the tuntap adapter. */
  n2n_desc_t          dev_desc;       /**< Hint description correlated with the edge */
  n2n_auth_t          auth;           /**< Authentication scheme and tokens */
} n2n_REGISTER_SUPER_t;


/* Linked with n2n_register_super_ack in n2n_pc_t. Only from supernode to edge. */
typedef struct n2n_REGISTER_SUPER_ACK {
  n2n_cookie_t         cookie;        /**< Return cookie from REGISTER_SUPER */
  n2n_mac_t            edgeMac;       /**< MAC registered to edge sending socket */
  n2n_ip_subnet_t      dev_addr;      /**< Assign an IP address to the tuntap adapter of edge. */
  uint16_t             lifetime;      /**< How long the registration will live */
  n2n_sock_t           sock;          /**< Sending sockets associated with edgeMac */

  /** The packet format provides additional supernode definitions here.
   * uint8_t count, then for each count there is one
   * n2n_sock_t.
   */
  uint8_t              num_sn;         /**< Number of supernodes that were send
                                        * even if we cannot store them all. If
                                        * non-zero then sn_bak is valid. */
} n2n_REGISTER_SUPER_ACK_t;


/* Linked with n2n_register_super_ack in n2n_pc_t. Only from supernode to edge. */
typedef struct n2n_REGISTER_SUPER_NAK {
  n2n_cookie_t        cookie;         /* Return cookie from REGISTER_SUPER */
  n2n_mac_t           srcMac;
} n2n_REGISTER_SUPER_NAK_t;


/* REGISTER_SUPER_ACK may contain extra payload (their number given by num_sn)
 * of following type describing a(nother) supernode */
typedef struct n2n_REGISTER_SUPER_ACK_payload {
  n2n_sock_t           sock;          /**< socket of supernode */
  n2n_mac_t            mac;           /**< MAC of supernode */
} n2n_REGISTER_SUPER_ACK_payload_t;


/* Linked with n2n_unregister_super in n2n_pc_t. */
typedef struct n2n_UNREGISTER_SUPER {
  n2n_auth_t auth;
  n2n_mac_t srcMac;
} n2n_UNREGISTER_SUPER_t;


typedef struct n2n_PEER_INFO {
  uint16_t                         aflags;
  n2n_mac_t                        srcMac;
  n2n_mac_t                        mac;
  n2n_sock_t                       sock;
  SN_SELECTION_CRITERION_DATA_TYPE data;
} n2n_PEER_INFO_t;


typedef struct n2n_QUERY_PEER {
  n2n_mac_t           srcMac;
  n2n_sock_t          sock;
  n2n_mac_t           targetMac;
} n2n_QUERY_PEER_t;

typedef struct n2n_buf n2n_buf_t;

struct peer_info {
  n2n_mac_t        mac_addr;
  n2n_ip_subnet_t  dev_addr;
  n2n_desc_t       dev_desc;
  n2n_sock_t       sock;
  n2n_cookie_t     last_cookie;
  n2n_auth_t       auth;
  int              timeout;
  uint8_t          purgeable;
  time_t           last_seen;
  time_t           last_p2p;
  time_t           last_sent_query;
  SN_SELECTION_CRITERION_DATA_TYPE selection_criterion;
  uint64_t         last_valid_time_stamp;
  char             *ip_addr;

  UT_hash_handle   hh; /* makes this structure hashable */
};

typedef struct peer_info peer_info_t;

typedef struct n2n_route {
  in_addr_t        net_addr;
  uint8_t          net_bitlen;
  in_addr_t        gateway;
} n2n_route_t;

typedef struct n2n_edge n2n_edge_t;

/* *************************************************** */

typedef enum {
  N2N_ACCEPT = 0,
  N2N_DROP =   1
} n2n_verdict;

/* *************************************************** */

typedef enum {
  FPP_UNKNOWN = 0,
  FPP_ARP =     1,
  FPP_TCP =     2,
  FPP_UDP =     3,
  FPP_ICMP =    4,
  FPP_IGMP =    5
} filter_packet_proto;


typedef struct packet_address_proto_info {
  in_addr_t           src_ip;
  uint16_t            src_port;
  in_addr_t           dst_ip;
  uint16_t            dst_port;
  filter_packet_proto proto;
}packet_address_proto_info_t;

typedef struct filter_rule_pair_cache {
  packet_address_proto_info_t key;

  uint8_t                     bool_allow_traffic;
  uint32_t                    active_count;

  UT_hash_handle hh;         /* makes this structure hashable */
} filter_rule_pair_cache_t;

struct network_traffic_filter;
typedef struct network_traffic_filter network_traffic_filter_t;

struct network_traffic_filter {
  n2n_verdict (*filter_packet_from_peer)(network_traffic_filter_t* filter, n2n_edge_t *eee,
                                         const n2n_sock_t *peer, uint8_t *payload, uint16_t payload_size);

  n2n_verdict (*filter_packet_from_tap)(network_traffic_filter_t* filter, n2n_edge_t *eee, uint8_t *payload, uint16_t payload_size);

  filter_rule_t *rules;

  filter_rule_pair_cache_t *connections_rule_cache;

  uint32_t work_count_scene_last_clear;

};

/* *************************************************** */

/* Callbacks allow external programs to attach functions in response to
 * N2N events. */
typedef struct n2n_edge_callbacks {
  /* The supernode registration has been updated */
  void (*sn_registration_updated)(n2n_edge_t *eee, time_t now, const n2n_sock_t *sn);

  /* A packet has been received from a peer. N2N_DROP can be returned to
   * drop the packet. The packet payload can be modified. This only allows
   * the packet size to be reduced */
  n2n_verdict (*packet_from_peer)(n2n_edge_t *eee, const n2n_sock_t *peer, uint8_t *payload, uint16_t *payload_size);

  /* A packet has been received from the TAP interface. N2N_DROP can be
   * returned to drop the packet. The packet payload can be modified.
   * This only allows the packet size to be reduced */
  n2n_verdict (*packet_from_tap)(n2n_edge_t *eee, uint8_t *payload, uint16_t *payload_size);

  /* Called whenever the IP address of the TAP interface changes. */
  void (*ip_address_changed)(n2n_edge_t *eee, uint32_t old_ip, uint32_t new_ip);

  /* Called periodically in the main loop. */
  void (*main_loop_period)(n2n_edge_t *eee, time_t now);
} n2n_edge_callbacks_t;

typedef struct n2n_tuntap_priv_config {
  char                tuntap_dev_name[N2N_IFNAMSIZ];
  char                ip_mode[N2N_IF_MODE_SIZE];
  dec_ip_str_t        ip_addr;
  dec_ip_str_t        netmask;
  char                device_mac[N2N_MACNAMSIZ];
  int                 mtu;
  uint8_t             daemon;
#ifndef WIN32
  uid_t               userid;
  gid_t               groupid;
#endif
} n2n_tuntap_priv_config_t;

/* *************************************************** */

typedef enum n2n_transform {
  N2N_TRANSFORM_ID_INVAL =    0,
  N2N_TRANSFORM_ID_NULL =     1,
  N2N_TRANSFORM_ID_TWOFISH =  2,
  N2N_TRANSFORM_ID_AES =      3,
  N2N_TRANSFORM_ID_CHACHA20 = 4,
  N2N_TRANSFORM_ID_SPECK =    5,
} n2n_transform_t;

struct n2n_trans_op; /* Circular definition */

typedef int             (*n2n_transdeinit_f)(struct n2n_trans_op * arg);
typedef void            (*n2n_transtick_f)(struct n2n_trans_op * arg, time_t now);
typedef int             (*n2n_transform_f)(struct n2n_trans_op * arg,
                                           uint8_t * outbuf,
                                           size_t out_len,
                                           const uint8_t * inbuf,
                                           size_t in_len,
                                           const n2n_mac_t peer_mac);
/** Holds the info associated with a data transform plugin.
 *
 *  When a packet arrives the transform ID is extracted. This defines the code
 *  to use to decode the packet content. The transform code then decodes the
 *  packet and consults its internal key lookup.
 */
typedef struct n2n_trans_op {
  void *              priv;   /* opaque data. Key schedule goes here. */
  uint8_t             no_encryption; /* 1 if this transop does not perform encryption */
  n2n_transform_t     transform_id;
  size_t              tx_cnt;
  size_t              rx_cnt;

  n2n_transdeinit_f   deinit; /* destructor function */
  n2n_transtick_f     tick;   /* periodic maintenance */
  n2n_transform_f     fwd;    /* encode a payload */
  n2n_transform_f     rev;    /* decode a payload */
} n2n_trans_op_t;


/* *************************************************** */

typedef struct n2n_edge_conf {
  struct peer_info    *supernodes;            /**< List of supernodes */
  n2n_route_t         *routes;                /**< Networks to route through n2n */
  n2n_community_t     community_name;         /**< The community. 16 full octets. */
  n2n_desc_t          dev_desc;               /**< The device description (hint) */
  uint8_t             header_encryption;      /**< Header encryption indicator. */
  he_context_t        *header_encryption_ctx; /**< Header encryption cipher context. */
  he_context_t        *header_iv_ctx;         /**< Header IV ecnryption cipher context, REMOVE as soon as seperte fileds for checksum and replay protection available */
  n2n_transform_t     transop_id;             /**< The transop to use. */
  uint8_t             compression;            /**< Compress outgoing data packets before encryption */
  uint16_t            num_routes;                   /**< Number of routes in routes */
  uint8_t             tuntap_ip_mode;         /**< Interface IP address allocated mode, eg. DHCP. */
  uint8_t             allow_routing;          /**< Accept packet no to interface address. */
  uint8_t             drop_multicast;         /**< Multicast ethernet addresses. */
  uint8_t             disable_pmtu_discovery; /**< Disable the Path MTU discovery. */
  uint8_t             allow_p2p;              /**< Allow P2P connection */
  uint8_t             sn_num;                 /**< Number of supernode addresses defined. */
  uint8_t             tos;                    /** TOS for sent packets */
  char                *encrypt_key;
  int                 register_interval;      /**< Interval for supernode registration, also used for UDP NAT hole punching. */
  int                 register_ttl;           /**< TTL for registration packet when UDP NAT hole punching through supernode. */
  int                 local_port;
  int                 mgmt_port;
  n2n_auth_t          auth;
  filter_rule_t       *network_traffic_filter_rules;
} n2n_edge_conf_t;


struct n2n_edge_stats {
  uint32_t tx_p2p;
  uint32_t rx_p2p;
  uint32_t tx_sup;
  uint32_t rx_sup;
  uint32_t tx_sup_broadcast;
  uint32_t rx_sup_broadcast;
};

struct n2n_edge {
  n2n_edge_conf_t     conf;

  /* Status */
  struct peer_info    *curr_sn;                /**< Currently active supernode. */
  uint8_t             sn_wait;                 /**< Whether we are waiting for a supernode response. */
  size_t              sup_attempts;            /**< Number of remaining attempts to this supernode. */
  tuntap_dev          device;                  /**< All about the TUNTAP device */
  n2n_trans_op_t      transop;                 /**< The transop to use when encoding */
  n2n_route_t         *sn_route_to_clean;      /**< Supernode route to clean */
  n2n_edge_callbacks_t cb;                     /**< API callbacks */
  void                *user_data;              /**< Can hold user data */
  uint64_t            sn_last_valid_time_stamp;/**< last valid time stamp from supernode */
  SN_SELECTION_CRITERION_DATA_TYPE sn_selection_criterion_common_data;

  /* Sockets */
  n2n_sock_t          supernode;
  int                 udp_sock;
  int                 udp_mgmt_sock;           /**< socket for status info. */

#ifndef SKIP_MULTICAST_PEERS_DISCOVERY
  n2n_sock_t          multicast_peer;          /**< Multicast peer group (for local edges) */
  int                 udp_multicast_sock;      /**< socket for local multicast registrations. */
  int                 multicast_joined;        /**< 1 if the group has been joined.*/
#endif

  /* Peers */
  struct peer_info *  known_peers;             /**< Edges we are connected to. */
  struct peer_info *  pending_peers;           /**< Edges we have tried to register with. */

  /* Timers */
  time_t              last_register_req;       /**< Check if time to re-register with super*/
  time_t              last_p2p;                /**< Last time p2p traffic was received. */
  time_t              last_sup;                /**< Last time a packet arrived from supernode. */
  time_t              last_sweep;              /**< Last time a sweep was performed. */
  time_t              start_time;              /**< For calculating uptime */


  struct n2n_edge_stats stats;                 /**< Statistics */

  n2n_tuntap_priv_config_t tuntap_priv_conf;   /**< Tuntap config */

  network_traffic_filter_t *network_traffic_filter;
};

typedef struct sn_stats {
  size_t errors;         /* Number of errors encountered. */
  size_t reg_super;      /* Number of REGISTER_SUPER requests received. */
  size_t reg_super_nak;  /* Number of REGISTER_SUPER requests declined. */
  size_t fwd;            /* Number of messages forwarded. */
  size_t broadcast;      /* Number of messages broadcast to a community. */
  time_t last_fwd;       /* Time when last message was forwarded. */
  time_t last_reg_super; /* Time when last REGISTER_SUPER was received. */
} sn_stats_t;

struct sn_community {
  char                community[N2N_COMMUNITY_SIZE];
  uint8_t             is_federation;          /* if not-zero, then the current community is the federation of supernodes */
  uint8_t             purgeable;              /* indicates purgeable community (fixed-name, predetermined (-c parameter) communties usually are unpurgeable) */
  uint8_t             header_encryption;      /* Header encryption indicator. */
  he_context_t        *header_encryption_ctx; /* Header encryption cipher context. */
  he_context_t        *header_iv_ctx;         /* Header IV ecnryption cipher context, REMOVE as soon as seperate fields for checksum and replay protection available */
  struct              peer_info *edges;       /* Link list of registered edges. */
  int64_t             number_enc_packets;     /* Number of encrypted packets handled so far, required for sorting from time to time */
  n2n_ip_subnet_t     auto_ip_net;            /* Address range of auto ip address service. */

  UT_hash_handle hh; /* makes this structure hashable */
};

/* Typedef'd pointer to get abstract datatype. */
typedef struct regex_t* re_t;

struct sn_community_regular_expression {
  re_t rule;         // compiles regular expression

  UT_hash_handle hh; /* makes this structure hashable */
};

typedef struct n2n_sn {
  time_t start_time; /* Used to measure uptime. */
  sn_stats_t stats;
  int daemon;           /* If non-zero then daemonise. */
  n2n_mac_t mac_addr;
  uint16_t lport;       /* Local UDP port to bind to. */
  uint16_t mport;       /* Management UDP port to bind to. */
  int sock;             /* Main socket for UDP traffic with edges. */
  int mgmt_sock;        /* management socket. */
  n2n_ip_subnet_t min_auto_ip_net; /* Address range of auto_ip service. */
  n2n_ip_subnet_t max_auto_ip_net; /* Address range of auto_ip service. */
#ifndef WIN32
  uid_t userid;
  gid_t groupid;
#endif
  int lock_communities; /* If true, only loaded and matching communities can be used. */
  struct sn_community *communities;
  struct sn_community_regular_expression *rules;
  struct sn_community *federation;
  n2n_auth_t auth;
} n2n_sn_t;




#endif /* _N2N_TYPEDEFS_H_ */