src/libcharon/kernel/kernel_ipsec.h

   1 /*
   2  * Copyright (C) 2016 Andreas Steffen
   3  * Copyright (C) 2006-2016 Tobias Brunner
   4  * Copyright (C) 2006 Daniel Roethlisberger
   5  * Copyright (C) 2005-2006 Martin Willi
   6  * Copyright (C) 2005 Jan Hutter
   7  * HSR Hochschule fuer Technik Rapperswil
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU General Public License as published by the
  11  * Free Software Foundation; either version 2 of the License, or (at your
  12  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  13  *
  14  * This program is distributed in the hope that it will be useful, but
  15  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  16  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  17  * for more details.
  18  */
  19
  20 /**
  21  * @defgroup kernel_ipsec kernel_ipsec
  22  * @{ @ingroup kernel
  23  */
  24
  25 #ifndef KERNEL_IPSEC_H_
  26 #define KERNEL_IPSEC_H_
  27
  28 typedef struct kernel_ipsec_t kernel_ipsec_t;
  29 typedef struct kernel_ipsec_sa_id_t kernel_ipsec_sa_id_t;
  30 typedef struct kernel_ipsec_add_sa_t kernel_ipsec_add_sa_t;
  31 typedef struct kernel_ipsec_update_sa_t kernel_ipsec_update_sa_t;
  32 typedef struct kernel_ipsec_query_sa_t kernel_ipsec_query_sa_t;
  33 typedef struct kernel_ipsec_del_sa_t kernel_ipsec_del_sa_t;
  34 typedef struct kernel_ipsec_policy_id_t kernel_ipsec_policy_id_t;
  35 typedef struct kernel_ipsec_manage_policy_t kernel_ipsec_manage_policy_t;
  36 typedef struct kernel_ipsec_query_policy_t kernel_ipsec_query_policy_t;
  37
  38 #include <networking/host.h>
  39 #include <ipsec/ipsec_types.h>
  40 #include <selectors/traffic_selector.h>
  41 #include <plugins/plugin.h>
  42 #include <kernel/kernel_interface.h>
  43
  44 /**
  45  * Data required to identify an SA in the kernel
  46  */
  47 struct kernel_ipsec_sa_id_t {
  48         /** Source address */
  49         host_t *src;
  50         /** Destination address */
  51         host_t *dst;
  52         /** SPI */
  53         uint32_t spi;
  54         /** Protocol (ESP/AH) */
  55         uint8_t proto;
  56         /** Optional mark */
  57         mark_t mark;
  58 };
  59
  60 /**
  61  * Data required to add an SA to the kernel
  62  */
  63 struct kernel_ipsec_add_sa_t {
  64         /** Reqid */
  65         uint32_t reqid;
  66         /** Mode (tunnel, transport...) */
  67         ipsec_mode_t mode;
  68         /** List of source traffic selectors */
  69         linked_list_t *src_ts;
  70         /** List of destination traffic selectors */
  71         linked_list_t *dst_ts;
  72         /** Lifetime configuration */
  73         lifetime_cfg_t *lifetime;
  74         /** Encryption algorithm */
  75         uint16_t enc_alg;
  76         /** Encryption key */
  77         chunk_t enc_key;
  78         /** Integrity protection algorithm */
  79         uint16_t int_alg;
  80         /** Integrity protection key */
  81         chunk_t int_key;
  82         /** Anti-replay window size */
  83         uint32_t replay_window;
  84         /** Traffic Flow Confidentiality padding */
  85         uint32_t tfc;
  86         /** IPComp transform */
  87         uint16_t ipcomp;
  88         /** CPI for IPComp */
  89         uint16_t cpi;
  90         /** TRUE to enable UDP encapsulation for NAT traversal */
  91         bool encap;
  92         /** TRUE to use Extended Sequence Numbers */
  93         bool esn;
  94         /** TRUE if initiator of the exchange creating the SA */
  95         bool initiator;
  96         /** TRUE if this is an inbound SA */
  97         bool inbound;
  98         /** TRUE if an SPI has already been allocated for this SA */
  99         bool update;
 100 };
 101
 102 /**
 103  * Data required to update the hosts of an SA in the kernel
 104  */
 105 struct kernel_ipsec_update_sa_t {
 106         /** CPI in case IPComp is used */
 107         uint16_t cpi;
 108         /** New source address */
 109         host_t *new_src;
 110         /** New destination address */
 111         host_t *new_dst;
 112         /** TRUE if UDP encapsulation is currently enabled */
 113         bool encap;
 114         /** TRUE to enable UDP encapsulation */
 115         bool new_encap;
 116 };
 117
 118 /**
 119  * Data required to query an SA in the kernel
 120  */
 121 struct kernel_ipsec_query_sa_t {
 122         uint16_t cpi;
 123 };
 124
 125 /**
 126  * Data required to delete an SA in the kernel
 127  */
 128 struct kernel_ipsec_del_sa_t {
 129         /** CPI in case IPComp is used */
 130         uint16_t cpi;
 131 };
 132
 133 /**
 134  * Data identifying a policy in the kernel
 135  */
 136 struct kernel_ipsec_policy_id_t {
 137         /** Direction of traffic */
 138         policy_dir_t dir;
 139         /** Source traffic selector */
 140         traffic_selector_t *src_ts;
 141         /** Destination traffic selector */
 142         traffic_selector_t *dst_ts;
 143         /** Optional mark */
 144         mark_t mark;
 145 };
 146
 147 /**
 148  * Data required to add/delete a policy to/from the kernel
 149  */
 150 struct kernel_ipsec_manage_policy_t {
 151         /** Type of policy */
 152         policy_type_t type;
 153         /** Priority class */
 154         policy_priority_t prio;
 155         /** Manually-set priority (automatic if set to 0) */
 156         uint32_t manual_prio;
 157         /** Source address of the SA(s) tied to this policy */
 158         host_t *src;
 159         /** Destination address of the SA(s) tied to this policy */
 160         host_t *dst;
 161         /** Details about the SA(s) tied to this policy */
 162         ipsec_sa_cfg_t *sa;
 163 };
 164
 165 /**
 166  * Data required to query a policy in the kernel
 167  */
 168 struct kernel_ipsec_query_policy_t {
 169 };
 170
 171 /**
 172  * Interface to the ipsec subsystem of the kernel.
 173  *
 174  * The kernel ipsec interface handles the communication with the kernel
 175  * for SA and policy management. It allows setup of these, and provides
 176  * further the handling of kernel events.
 177  * Policy information are cached in the interface. This is necessary to do
 178  * reference counting. The Linux kernel does not allow the same policy
 179  * installed twice, but we need this as CHILD_SA exist multiple times
 180  * when rekeying. Thats why we do reference counting of policies.
 181  */
 182 struct kernel_ipsec_t {
 183
 184         /**
 185          * Get the feature set supported by this kernel backend.
 186          *
 187          * @return                              ORed feature-set of backend
 188          */
 189         kernel_feature_t (*get_features)(kernel_ipsec_t *this);
 190
 191         /**
 192          * Get a SPI from the kernel.
 193          *
 194          * @param src           source address of SA
 195          * @param dst           destination address of SA
 196          * @param protocol      protocol for SA (ESP/AH)
 197          * @param spi           allocated spi
 198          * @return                      SUCCESS if operation completed
 199          */
 200         status_t (*get_spi)(kernel_ipsec_t *this, host_t *src, host_t *dst,
 201                                                 uint8_t protocol, uint32_t *spi);
 202
 203         /**
 204          * Get a Compression Parameter Index (CPI) from the kernel.
 205          *
 206          * @param src           source address of SA
 207          * @param dst           destination address of SA
 208          * @param cpi           allocated cpi
 209          * @return                      SUCCESS if operation completed
 210          */
 211         status_t (*get_cpi)(kernel_ipsec_t *this, host_t *src, host_t *dst,
 212                                                 uint16_t *cpi);
 213
 214         /**
 215          * Add an SA to the SAD.
 216          *
 217          * This function does install a single SA for a single protocol in one
 218          * direction.
 219          *
 220          * @param id                    data identifying this SA
 221          * @param data                  data for this SA
 222          * @return                              SUCCESS if operation completed
 223          */
 224         status_t (*add_sa)(kernel_ipsec_t *this, kernel_ipsec_sa_id_t *id,
 225                                            kernel_ipsec_add_sa_t *data);
 226
 227         /**
 228          * Update the hosts on an installed SA.
 229          *
 230          * We cannot directly update the destination address as the kernel
 231          * requires the spi, the protocol AND the destination address (and family)
 232          * to identify SAs. Therefore if the destination address changed we
 233          * create a new SA and delete the old one.
 234          *
 235          * @param id                    data identifying this SA
 236          * @param data                  updated data for this SA
 237          * @return                              SUCCESS if operation completed, NOT_SUPPORTED if
 238          *                                              the kernel interface can't update the SA
 239          */
 240         status_t (*update_sa)(kernel_ipsec_t *this, kernel_ipsec_sa_id_t *id,
 241                                                   kernel_ipsec_update_sa_t *data);
 242
 243         /**
 244          * Query the number of bytes processed by an SA from the SAD.
 245          *
 246          * @param id                    data identifying this SA
 247          * @param data                  data to query the SA
 248          * @param[out] bytes    the number of bytes processed by SA
 249          * @param[out] packets  number of packets processed by SA
 250          * @param[out] time             last (monotonic) time of SA use
 251          * @return                              SUCCESS if operation completed
 252          */
 253         status_t (*query_sa)(kernel_ipsec_t *this, kernel_ipsec_sa_id_t *id,
 254                                                  kernel_ipsec_query_sa_t *data, uint64_t *bytes,
 255                                                  uint64_t *packets, time_t *time);
 256
 257         /**
 258          * Delete a previously installed SA from the SAD.
 259          *
 260          * @param id                    data identifying this SA
 261          * @param data                  data to delete the SA
 262          * @return                              SUCCESS if operation completed
 263          */
 264         status_t (*del_sa)(kernel_ipsec_t *this, kernel_ipsec_sa_id_t *id,
 265                                            kernel_ipsec_del_sa_t *data);
 266
 267         /**
 268          * Flush all SAs from the SAD.
 269          *
 270          * @return                              SUCCESS if operation completed
 271          */
 272         status_t (*flush_sas)(kernel_ipsec_t *this);
 273
 274         /**
 275          * Add a policy to the SPD.
 276          *
 277          * @param id                    data identifying this policy
 278          * @param data                  data for this policy
 279          * @return                              SUCCESS if operation completed
 280          */
 281         status_t (*add_policy)(kernel_ipsec_t *this,
 282                                                    kernel_ipsec_policy_id_t *id,
 283                                                    kernel_ipsec_manage_policy_t *data);
 284
 285         /**
 286          * Query the use time of a policy.
 287          *
 288          * The use time of a policy is the time the policy was used for the last
 289          * time. It is not the system time, but a monotonic timestamp as returned
 290          * by time_monotonic.
 291          *
 292          * @param id                    data identifying this policy
 293          * @param data                  data to query the policy
 294          * @param[out] use_time the monotonic timestamp of this SA's last use
 295          * @return                              SUCCESS if operation completed
 296          */
 297         status_t (*query_policy)(kernel_ipsec_t *this,
 298                                                          kernel_ipsec_policy_id_t *id,
 299                                                          kernel_ipsec_query_policy_t *data,
 300                                                          time_t *use_time);
 301
 302         /**
 303          * Remove a policy from the SPD.
 304          *
 305          * @param id                    data identifying this policy
 306          * @param data                  data for this policy
 307          * @return                              SUCCESS if operation completed
 308          */
 309         status_t (*del_policy)(kernel_ipsec_t *this,
 310                                                    kernel_ipsec_policy_id_t *id,
 311                                                    kernel_ipsec_manage_policy_t *data);
 312
 313         /**
 314          * Flush all policies from the SPD.
 315          *
 316          * @return                              SUCCESS if operation completed
 317          */
 318         status_t (*flush_policies)(kernel_ipsec_t *this);
 319
 320         /**
 321          * Install a bypass policy for the given socket.
 322          *
 323          * @param fd                    socket file descriptor to setup policy for
 324          * @param family                protocol family of the socket
 325          * @return                              TRUE of policy set up successfully
 326          */
 327         bool (*bypass_socket)(kernel_ipsec_t *this, int fd, int family);
 328
 329         /**
 330          * Enable decapsulation of ESP-in-UDP packets for the given port/socket.
 331          *
 332          * @param fd                    socket file descriptor
 333          * @param family                protocol family of the socket
 334          * @param port                  the UDP port
 335          * @return                              TRUE if UDP decapsulation was enabled successfully
 336          */
 337         bool (*enable_udp_decap)(kernel_ipsec_t *this, int fd, int family,
 338                                                          uint16_t port);
 339
 340         /**
 341          * Destroy the implementation.
 342          */
 343         void (*destroy)(kernel_ipsec_t *this);
 344 };
 345
 346 /**
 347  * Helper function to (un-)register IPsec kernel interfaces from plugin features.
 348  *
 349  * This function is a plugin_feature_callback_t and can be used with the
 350  * PLUGIN_CALLBACK macro to register an IPsec kernel interface constructor.
 351  *
 352  * @param plugin                plugin registering the kernel interface
 353  * @param feature               associated plugin feature
 354  * @param reg                   TRUE to register, FALSE to unregister
 355  * @param data                  data passed to callback, an kernel_ipsec_constructor_t
 356  */
 357 bool kernel_ipsec_register(plugin_t *plugin, plugin_feature_t *feature,
 358                                                    bool reg, void *data);
 359
 360 #endif /** KERNEL_IPSEC_H_ @}*/