src/libhydra/kernel/kernel_net.h

   1 /*
   2  * Copyright (C) 2008 Tobias Brunner
   3  * Copyright (C) 2007 Martin Willi
   4  * Hochschule fuer Technik Rapperswil
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the
   8  * Free Software Foundation; either version 2 of the License, or (at your
   9  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  13  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * for more details.
  15  */
  16
  17 /**
  18  * @defgroup kernel_net kernel_net
  19  * @{ @ingroup hkernel
  20  */
  21
  22 #ifndef KERNEL_NET_H_
  23 #define KERNEL_NET_H_
  24
  25 typedef struct kernel_net_t kernel_net_t;
  26
  27 #include <utils/enumerator.h>
  28 #include <utils/host.h>
  29 #include <plugins/plugin.h>
  30
  31 /**
  32  * Interface to the network subsystem of the kernel.
  33  *
  34  * The kernel network interface handles the communication with the kernel
  35  * for interface and IP address management.
  36  */
  37 struct kernel_net_t {
  38
  39         /**
  40          * Get our outgoing source address for a destination.
  41          *
  42          * Does a route lookup to get the source address used to reach dest.
  43          * The returned host is allocated and must be destroyed.
  44          * An optional src address can be used to check if a route is available
  45          * for given source to dest.
  46          *
  47          * @param dest                  target destination address
  48          * @param src                   source address to check, or NULL
  49          * @return                              outgoing source address, NULL if unreachable
  50          */
  51         host_t* (*get_source_addr)(kernel_net_t *this, host_t *dest, host_t *src);
  52
  53         /**
  54          * Get the next hop for a destination.
  55          *
  56          * Does a route lookup to get the next hop used to reach dest.
  57          * The returned host is allocated and must be destroyed.
  58          *
  59          * @param dest                  target destination address
  60          * @return                              next hop address, NULL if unreachable
  61          */
  62         host_t* (*get_nexthop)(kernel_net_t *this, host_t *dest);
  63
  64         /**
  65          * Get the interface name of a local address.
  66          *
  67          * @param host                  address to get interface name from
  68          * @return                              allocated interface name, or NULL if not found
  69          */
  70         char* (*get_interface) (kernel_net_t *this, host_t *host);
  71
  72         /**
  73          * Creates an enumerator over all local addresses.
  74          *
  75          * This function blocks an internal cached address list until the
  76          * enumerator gets destroyed.
  77          * The hosts are read-only, do not modify of free.
  78          *
  79          * @param include_down_ifaces   TRUE to enumerate addresses from down interfaces
  80          * @param include_virtual_ips   TRUE to enumerate virtual ip addresses
  81          * @return                                              enumerator over host_t's
  82          */
  83         enumerator_t *(*create_address_enumerator) (kernel_net_t *this,
  84                                                 bool include_down_ifaces, bool include_virtual_ips);
  85
  86         /**
  87          * Add a virtual IP to an interface.
  88          *
  89          * Virtual IPs are attached to an interface. If an IP is added multiple
  90          * times, the IP is refcounted and not removed until del_ip() was called
  91          * as many times as add_ip().
  92          * The virtual IP is attached to the interface where the iface_ip is found.
  93          *
  94          * @param virtual_ip    virtual ip address to assign
  95          * @param iface_ip              IP of an interface to attach virtual IP
  96          * @return                              SUCCESS if operation completed
  97          */
  98         status_t (*add_ip) (kernel_net_t *this, host_t *virtual_ip,
  99                                                 host_t *iface_ip);
 100
 101         /**
 102          * Remove a virtual IP from an interface.
 103          *
 104          * The kernel interface uses refcounting, see add_ip().
 105          *
 106          * @param virtual_ip    virtual ip address to assign
 107          * @return                              SUCCESS if operation completed
 108          */
 109         status_t (*del_ip) (kernel_net_t *this, host_t *virtual_ip);
 110
 111         /**
 112          * Add a route.
 113          *
 114          * @param dst_net               destination net
 115          * @param prefixlen             destination net prefix length
 116          * @param gateway               gateway for this route
 117          * @param src_ip                sourc ip of the route
 118          * @param if_name               name of the interface the route is bound to
 119          * @return                              SUCCESS if operation completed
 120          *                                              ALREADY_DONE if the route already exists
 121          */
 122         status_t (*add_route) (kernel_net_t *this, chunk_t dst_net,
 123                                                    u_int8_t prefixlen, host_t *gateway, host_t *src_ip,
 124                                                    char *if_name);
 125
 126         /**
 127          * Delete a route.
 128          *
 129          * @param dst_net               destination net
 130          * @param prefixlen             destination net prefix length
 131          * @param gateway               gateway for this route
 132          * @param src_ip                sourc ip of the route
 133          * @param if_name               name of the interface the route is bound to
 134          * @return                              SUCCESS if operation completed
 135          */
 136         status_t (*del_route) (kernel_net_t *this, chunk_t dst_net,
 137                                                    u_int8_t prefixlen, host_t *gateway, host_t *src_ip,
 138                                                    char *if_name);
 139
 140         /**
 141          * Destroy the implementation.
 142          */
 143         void (*destroy) (kernel_net_t *this);
 144 };
 145
 146 /**
 147  * Helper function to (un-)register net kernel interfaces from plugin features.
 148  *
 149  * This function is a plugin_feature_callback_t and can be used with the
 150  * PLUGIN_CALLBACK macro to register an net kernel interface constructor.
 151  *
 152  * @param plugin                plugin registering the kernel interface
 153  * @param feature               associated plugin feature
 154  * @param reg                   TRUE to register, FALSE to unregister
 155  * @param data                  data passed to callback, an kernel_net_constructor_t
 156  */
 157 bool kernel_net_register(plugin_t *plugin, plugin_feature_t *feature,
 158                                                  bool reg, void *data);
 159
 160 #endif /** KERNEL_NET_H_ @}*/