include/net/xfrm.h

   1 #ifndef _NET_XFRM_H
   2 #define _NET_XFRM_H
   3
   4 #include <linux/compiler.h>
   5 #include <linux/xfrm.h>
   6 #include <linux/spinlock.h>
   7 #include <linux/list.h>
   8 #include <linux/skbuff.h>
   9 #include <linux/socket.h>
  10 #include <linux/pfkeyv2.h>
  11 #include <linux/ipsec.h>
  12 #include <linux/in6.h>
  13 #include <linux/mutex.h>
  14 #include <linux/audit.h>
  15 #include <linux/slab.h>
  16
  17 #include <net/sock.h>
  18 #include <net/dst.h>
  19 #include <net/ip.h>
  20 #include <net/route.h>
  21 #include <net/ipv6.h>
  22 #include <net/ip6_fib.h>
  23 #include <net/flow.h>
  24
  25 #include <linux/interrupt.h>
  26
  27 #ifdef CONFIG_XFRM_STATISTICS
  28 #include <net/snmp.h>
  29 #endif
  30
  31 #define XFRM_PROTO_ESP          50
  32 #define XFRM_PROTO_AH           51
  33 #define XFRM_PROTO_COMP         108
  34 #define XFRM_PROTO_IPIP         4
  35 #define XFRM_PROTO_IPV6         41
  36 #define XFRM_PROTO_ROUTING      IPPROTO_ROUTING
  37 #define XFRM_PROTO_DSTOPTS      IPPROTO_DSTOPTS
  38
  39 #define XFRM_ALIGN4(len)        (((len) + 3) & ~3)
  40 #define XFRM_ALIGN8(len)        (((len) + 7) & ~7)
  41 #define MODULE_ALIAS_XFRM_MODE(family, encap) \
  42         MODULE_ALIAS("xfrm-mode-" __stringify(family) "-" __stringify(encap))
  43 #define MODULE_ALIAS_XFRM_TYPE(family, proto) \
  44         MODULE_ALIAS("xfrm-type-" __stringify(family) "-" __stringify(proto))
  45
  46 #ifdef CONFIG_XFRM_STATISTICS
  47 #define XFRM_INC_STATS(net, field)      SNMP_INC_STATS((net)->mib.xfrm_statistics, field)
  48 #define XFRM_INC_STATS_BH(net, field)   SNMP_INC_STATS_BH((net)->mib.xfrm_statistics, field)
  49 #define XFRM_INC_STATS_USER(net, field) SNMP_INC_STATS_USER((net)-mib.xfrm_statistics, field)
  50 #else
  51 #define XFRM_INC_STATS(net, field)      ((void)(net))
  52 #define XFRM_INC_STATS_BH(net, field)   ((void)(net))
  53 #define XFRM_INC_STATS_USER(net, field) ((void)(net))
  54 #endif
  55
  56 extern struct mutex xfrm_cfg_mutex;
  57
  58 /* Organization of SPD aka "XFRM rules"
  59    ------------------------------------
  60
  61    Basic objects:
  62    - policy rule, struct xfrm_policy (=SPD entry)
  63    - bundle of transformations, struct dst_entry == struct xfrm_dst (=SA bundle)
  64    - instance of a transformer, struct xfrm_state (=SA)
  65    - template to clone xfrm_state, struct xfrm_tmpl
  66
  67    SPD is plain linear list of xfrm_policy rules, ordered by priority.
  68    (To be compatible with existing pfkeyv2 implementations,
  69    many rules with priority of 0x7fffffff are allowed to exist and
  70    such rules are ordered in an unpredictable way, thanks to bsd folks.)
  71
  72    Lookup is plain linear search until the first match with selector.
  73
  74    If "action" is "block", then we prohibit the flow, otherwise:
  75    if "xfrms_nr" is zero, the flow passes untransformed. Otherwise,
  76    policy entry has list of up to XFRM_MAX_DEPTH transformations,
  77    described by templates xfrm_tmpl. Each template is resolved
  78    to a complete xfrm_state (see below) and we pack bundle of transformations
  79    to a dst_entry returned to requestor.
  80
  81    dst -. xfrm  .-> xfrm_state #1
  82     |---. child .-> dst -. xfrm .-> xfrm_state #2
  83                      |---. child .-> dst -. xfrm .-> xfrm_state #3
  84                                       |---. child .-> NULL
  85
  86    Bundles are cached at xrfm_policy struct (field ->bundles).
  87
  88
  89    Resolution of xrfm_tmpl
  90    -----------------------
  91    Template contains:
  92    1. ->mode            Mode: transport or tunnel
  93    2. ->id.proto        Protocol: AH/ESP/IPCOMP
  94    3. ->id.daddr        Remote tunnel endpoint, ignored for transport mode.
  95       Q: allow to resolve security gateway?
  96    4. ->id.spi          If not zero, static SPI.
  97    5. ->saddr           Local tunnel endpoint, ignored for transport mode.
  98    6. ->algos           List of allowed algos. Plain bitmask now.
  99       Q: ealgos, aalgos, calgos. What a mess...
 100    7. ->share           Sharing mode.
 101       Q: how to implement private sharing mode? To add struct sock* to
 102       flow id?
 103
 104    Having this template we search through SAD searching for entries
 105    with appropriate mode/proto/algo, permitted by selector.
 106    If no appropriate entry found, it is requested from key manager.
 107
 108    PROBLEMS:
 109    Q: How to find all the bundles referring to a physical path for
 110       PMTU discovery? Seems, dst should contain list of all parents...
 111       and enter to infinite locking hierarchy disaster.
 112       No! It is easier, we will not search for them, let them find us.
 113       We add genid to each dst plus pointer to genid of raw IP route,
 114       pmtu disc will update pmtu on raw IP route and increase its genid.
 115       dst_check() will see this for top level and trigger resyncing
 116       metrics. Plus, it will be made via sk->sk_dst_cache. Solved.
 117  */
 118
 119 struct xfrm_state_walk {
 120         struct list_head        all;
 121         u8                      state;
 122         union {
 123                 u8              dying;
 124                 u8              proto;
 125         };
 126         u32                     seq;
 127 };
 128
 129 /* Full description of state of transformer. */
 130 struct xfrm_state {
 131 #ifdef CONFIG_NET_NS
 132         struct net              *xs_net;
 133 #endif
 134         union {
 135                 struct hlist_node       gclist;
 136                 struct hlist_node       bydst;
 137         };
 138         struct hlist_node       bysrc;
 139         struct hlist_node       byspi;
 140
 141         atomic_t                refcnt;
 142         spinlock_t              lock;
 143
 144         struct xfrm_id          id;
 145         struct xfrm_selector    sel;
 146         struct xfrm_mark        mark;
 147         u32                     tfcpad;
 148
 149         u32                     genid;
 150
 151         /* Key manager bits */
 152         struct xfrm_state_walk  km;
 153
 154         /* Parameters of this state. */
 155         struct {
 156                 u32             reqid;
 157                 u8              mode;
 158                 u8              replay_window;
 159                 u8              aalgo, ealgo, calgo;
 160                 u8              flags;
 161                 u16             family;
 162                 xfrm_address_t  saddr;
 163                 int             header_len;
 164                 int             trailer_len;
 165                 u32             extra_flags;
 166         } props;
 167
 168         struct xfrm_lifetime_cfg lft;
 169
 170         /* Data for transformer */
 171         struct xfrm_algo_auth   *aalg;
 172         struct xfrm_algo        *ealg;
 173         struct xfrm_algo        *calg;
 174         struct xfrm_algo_aead   *aead;
 175
 176         /* Data for encapsulator */
 177         struct xfrm_encap_tmpl  *encap;
 178
 179         /* Data for care-of address */
 180         xfrm_address_t  *coaddr;
 181
 182         /* IPComp needs an IPIP tunnel for handling uncompressed packets */
 183         struct xfrm_state       *tunnel;
 184
 185         /* If a tunnel, number of users + 1 */
 186         atomic_t                tunnel_users;
 187
 188         /* State for replay detection */
 189         struct xfrm_replay_state replay;
 190         struct xfrm_replay_state_esn *replay_esn;
 191
 192         /* Replay detection state at the time we sent the last notification */
 193         struct xfrm_replay_state preplay;
 194         struct xfrm_replay_state_esn *preplay_esn;
 195
 196         /* The functions for replay detection. */
 197         struct xfrm_replay      *repl;
 198
 199         /* internal flag that only holds state for delayed aevent at the
 200          * moment
 201         */
 202         u32                     xflags;
 203
 204         /* Replay detection notification settings */
 205         u32                     replay_maxage;
 206         u32                     replay_maxdiff;
 207
 208         /* Replay detection notification timer */
 209         struct timer_list       rtimer;
 210
 211         /* Statistics */
 212         struct xfrm_stats       stats;
 213
 214         struct xfrm_lifetime_cur curlft;
 215         struct tasklet_hrtimer  mtimer;
 216
 217         /* used to fix curlft->add_time when changing date */
 218         long            saved_tmo;
 219
 220         /* Last used time */
 221         unsigned long           lastused;
 222
 223         /* Reference to data common to all the instances of this
 224          * transformer. */
 225         const struct xfrm_type  *type;
 226         struct xfrm_mode        *inner_mode;
 227         struct xfrm_mode        *inner_mode_iaf;
 228         struct xfrm_mode        *outer_mode;
 229
 230         /* Security context */
 231         struct xfrm_sec_ctx     *security;
 232
 233         /* Private data of this transformer, format is opaque,
 234          * interpreted by xfrm_type methods. */
 235         void                    *data;
 236 };
 237
 238 static inline struct net *xs_net(struct xfrm_state *x)
 239 {
 240         return read_pnet(&x->xs_net);
 241 }
 242
 243 /* xflags - make enum if more show up */
 244 #define XFRM_TIME_DEFER 1
 245 #define XFRM_SOFT_EXPIRE 2
 246
 247 enum {
 248         XFRM_STATE_VOID,
 249         XFRM_STATE_ACQ,
 250         XFRM_STATE_VALID,
 251         XFRM_STATE_ERROR,
 252         XFRM_STATE_EXPIRED,
 253         XFRM_STATE_DEAD
 254 };
 255
 256 /* callback structure passed from either netlink or pfkey */
 257 struct km_event {
 258         union {
 259                 u32 hard;
 260                 u32 proto;
 261                 u32 byid;
 262                 u32 aevent;
 263                 u32 type;
 264         } data;
 265
 266         u32     seq;
 267         u32     portid;
 268         u32     event;
 269         struct net *net;
 270 };
 271
 272 struct xfrm_replay {
 273         void    (*advance)(struct xfrm_state *x, __be32 net_seq);
 274         int     (*check)(struct xfrm_state *x,
 275                          struct sk_buff *skb,
 276                          __be32 net_seq);
 277         int     (*recheck)(struct xfrm_state *x,
 278                            struct sk_buff *skb,
 279                            __be32 net_seq);
 280         void    (*notify)(struct xfrm_state *x, int event);
 281         int     (*overflow)(struct xfrm_state *x, struct sk_buff *skb);
 282 };
 283
 284 struct net_device;
 285 struct xfrm_type;
 286 struct xfrm_dst;
 287 struct xfrm_policy_afinfo {
 288         unsigned short          family;
 289         struct dst_ops          *dst_ops;
 290         void                    (*garbage_collect)(struct net *net);
 291         struct dst_entry        *(*dst_lookup)(struct net *net, int tos,
 292                                                const xfrm_address_t *saddr,
 293                                                const xfrm_address_t *daddr);
 294         int                     (*get_saddr)(struct net *net, xfrm_address_t *saddr, xfrm_address_t *daddr);
 295         void                    (*decode_session)(struct sk_buff *skb,
 296                                                   struct flowi *fl,
 297                                                   int reverse);
 298         int                     (*get_tos)(const struct flowi *fl);
 299         void                    (*init_dst)(struct net *net,
 300                                             struct xfrm_dst *dst);
 301         int                     (*init_path)(struct xfrm_dst *path,
 302                                              struct dst_entry *dst,
 303                                              int nfheader_len);
 304         int                     (*fill_dst)(struct xfrm_dst *xdst,
 305                                             struct net_device *dev,
 306                                             const struct flowi *fl);
 307         struct dst_entry        *(*blackhole_route)(struct net *net, struct dst_entry *orig);
 308 };
 309
 310 extern int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo);
 311 extern int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo);
 312 extern void km_policy_notify(struct xfrm_policy *xp, int dir, const struct km_event *c);
 313 extern void km_state_notify(struct xfrm_state *x, const struct km_event *c);
 314
 315 struct xfrm_tmpl;
 316 extern int km_query(struct xfrm_state *x, struct xfrm_tmpl *t, struct xfrm_policy *pol);
 317 extern void km_state_expired(struct xfrm_state *x, int hard, u32 portid);
 318 extern int __xfrm_state_delete(struct xfrm_state *x);
 319
 320 struct xfrm_state_afinfo {
 321         unsigned int            family;
 322         unsigned int            proto;
 323         __be16                  eth_proto;
 324         struct module           *owner;
 325         const struct xfrm_type  *type_map[IPPROTO_MAX];
 326         struct xfrm_mode        *mode_map[XFRM_MODE_MAX];
 327         int                     (*init_flags)(struct xfrm_state *x);
 328         void                    (*init_tempsel)(struct xfrm_selector *sel,
 329                                                 const struct flowi *fl);
 330         void                    (*init_temprop)(struct xfrm_state *x,
 331                                                 const struct xfrm_tmpl *tmpl,
 332                                                 const xfrm_address_t *daddr,
 333                                                 const xfrm_address_t *saddr);
 334         int                     (*tmpl_sort)(struct xfrm_tmpl **dst, struct xfrm_tmpl **src, int n);
 335         int                     (*state_sort)(struct xfrm_state **dst, struct xfrm_state **src, int n);
 336         int                     (*output)(struct sk_buff *skb);
 337         int                     (*output_finish)(struct sk_buff *skb);
 338         int                     (*extract_input)(struct xfrm_state *x,
 339                                                  struct sk_buff *skb);
 340         int                     (*extract_output)(struct xfrm_state *x,
 341                                                   struct sk_buff *skb);
 342         int                     (*transport_finish)(struct sk_buff *skb,
 343                                                     int async);
 344 };
 345
 346 extern int xfrm_state_register_afinfo(struct xfrm_state_afinfo *afinfo);
 347 extern int xfrm_state_unregister_afinfo(struct xfrm_state_afinfo *afinfo);
 348
 349 extern void xfrm_state_delete_tunnel(struct xfrm_state *x);
 350
 351 struct xfrm_type {
 352         char                    *description;
 353         struct module           *owner;
 354         u8                      proto;
 355         u8                      flags;
 356 #define XFRM_TYPE_NON_FRAGMENT  1
 357 #define XFRM_TYPE_REPLAY_PROT   2
 358 #define XFRM_TYPE_LOCAL_COADDR  4
 359 #define XFRM_TYPE_REMOTE_COADDR 8
 360
 361         int                     (*init_state)(struct xfrm_state *x);
 362         void                    (*destructor)(struct xfrm_state *);
 363         int                     (*input)(struct xfrm_state *, struct sk_buff *skb);
 364         int                     (*output)(struct xfrm_state *, struct sk_buff *pskb);
 365         int                     (*reject)(struct xfrm_state *, struct sk_buff *,
 366                                           const struct flowi *);
 367         int                     (*hdr_offset)(struct xfrm_state *, struct sk_buff *, u8 **);
 368         /* Estimate maximal size of result of transformation of a dgram */
 369         u32                     (*get_mtu)(struct xfrm_state *, int size);
 370 };
 371
 372 extern int xfrm_register_type(const struct xfrm_type *type, unsigned short family);
 373 extern int xfrm_unregister_type(const struct xfrm_type *type, unsigned short family);
 374
 375 struct xfrm_mode {
 376         /*
 377          * Remove encapsulation header.
 378          *
 379          * The IP header will be moved over the top of the encapsulation
 380          * header.
 381          *
 382          * On entry, the transport header shall point to where the IP header
 383          * should be and the network header shall be set to where the IP
 384          * header currently is.  skb->data shall point to the start of the
 385          * payload.
 386          */
 387         int (*input2)(struct xfrm_state *x, struct sk_buff *skb);
 388
 389         /*
 390          * This is the actual input entry point.
 391          *
 392          * For transport mode and equivalent this would be identical to
 393          * input2 (which does not need to be set).  While tunnel mode
 394          * and equivalent would set this to the tunnel encapsulation function
 395          * xfrm4_prepare_input that would in turn call input2.
 396          */
 397         int (*input)(struct xfrm_state *x, struct sk_buff *skb);
 398
 399         /*
 400          * Add encapsulation header.
 401          *
 402          * On exit, the transport header will be set to the start of the
 403          * encapsulation header to be filled in by x->type->output and
 404          * the mac header will be set to the nextheader (protocol for
 405          * IPv4) field of the extension header directly preceding the
 406          * encapsulation header, or in its absence, that of the top IP
 407          * header.  The value of the network header will always point
 408          * to the top IP header while skb->data will point to the payload.
 409          */
 410         int (*output2)(struct xfrm_state *x,struct sk_buff *skb);
 411
 412         /*
 413          * This is the actual output entry point.
 414          *
 415          * For transport mode and equivalent this would be identical to
 416          * output2 (which does not need to be set).  While tunnel mode
 417          * and equivalent would set this to a tunnel encapsulation function
 418          * (xfrm4_prepare_output or xfrm6_prepare_output) that would in turn
 419          * call output2.
 420          */
 421         int (*output)(struct xfrm_state *x, struct sk_buff *skb);
 422
 423         struct xfrm_state_afinfo *afinfo;
 424         struct module *owner;
 425         unsigned int encap;
 426         int flags;
 427 };
 428
 429 /* Flags for xfrm_mode. */
 430 enum {
 431         XFRM_MODE_FLAG_TUNNEL = 1,
 432 };
 433
 434 extern int xfrm_register_mode(struct xfrm_mode *mode, int family);
 435 extern int xfrm_unregister_mode(struct xfrm_mode *mode, int family);
 436
 437 static inline int xfrm_af2proto(unsigned int family)
 438 {
 439         switch(family) {
 440         case AF_INET:
 441                 return IPPROTO_IPIP;
 442         case AF_INET6:
 443                 return IPPROTO_IPV6;
 444         default:
 445                 return 0;
 446         }
 447 }
 448
 449 static inline struct xfrm_mode *xfrm_ip2inner_mode(struct xfrm_state *x, int ipproto)
 450 {
 451         if ((ipproto == IPPROTO_IPIP && x->props.family == AF_INET) ||
 452             (ipproto == IPPROTO_IPV6 && x->props.family == AF_INET6))
 453                 return x->inner_mode;
 454         else
 455                 return x->inner_mode_iaf;
 456 }
 457
 458 struct xfrm_tmpl {
 459 /* id in template is interpreted as:
 460  * daddr - destination of tunnel, may be zero for transport mode.
 461  * spi   - zero to acquire spi. Not zero if spi is static, then
 462  *         daddr must be fixed too.
 463  * proto - AH/ESP/IPCOMP
 464  */
 465         struct xfrm_id          id;
 466
 467 /* Source address of tunnel. Ignored, if it is not a tunnel. */
 468         xfrm_address_t          saddr;
 469
 470         unsigned short          encap_family;
 471
 472         u32                     reqid;
 473
 474 /* Mode: transport, tunnel etc. */
 475         u8                      mode;
 476
 477 /* Sharing mode: unique, this session only, this user only etc. */
 478         u8                      share;
 479
 480 /* May skip this transfomration if no SA is found */
 481         u8                      optional;
 482
 483 /* Skip aalgos/ealgos/calgos checks. */
 484         u8                      allalgs;
 485
 486 /* Bit mask of algos allowed for acquisition */
 487         u32                     aalgos;
 488         u32                     ealgos;
 489         u32                     calgos;
 490 };
 491
 492 #define XFRM_MAX_DEPTH          6
 493
 494 struct xfrm_policy_walk_entry {
 495         struct list_head        all;
 496         u8                      dead;
 497 };
 498
 499 struct xfrm_policy_walk {
 500         struct xfrm_policy_walk_entry walk;
 501         u8 type;
 502         u32 seq;
 503 };
 504
 505 struct xfrm_policy_queue {
 506         struct sk_buff_head     hold_queue;
 507         struct timer_list       hold_timer;
 508         unsigned long           timeout;
 509 };
 510
 511 struct xfrm_policy {
 512 #ifdef CONFIG_NET_NS
 513         struct net              *xp_net;
 514 #endif
 515         struct hlist_node       bydst;
 516         struct hlist_node       byidx;
 517
 518         /* This lock only affects elements except for entry. */
 519         rwlock_t                lock;
 520         atomic_t                refcnt;
 521         struct timer_list       timer;
 522
 523         struct flow_cache_object flo;
 524         atomic_t                genid;
 525         u32                     priority;
 526         u32                     index;
 527         struct xfrm_mark        mark;
 528         struct xfrm_selector    selector;
 529         struct xfrm_lifetime_cfg lft;
 530         struct xfrm_lifetime_cur curlft;
 531         struct xfrm_policy_walk_entry walk;
 532         struct xfrm_policy_queue polq;
 533         u8                      type;
 534         u8                      action;
 535         u8                      flags;
 536         u8                      xfrm_nr;
 537         u16                     family;
 538         struct xfrm_sec_ctx     *security;
 539         struct xfrm_tmpl        xfrm_vec[XFRM_MAX_DEPTH];
 540 };
 541
 542 static inline struct net *xp_net(const struct xfrm_policy *xp)
 543 {
 544         return read_pnet(&xp->xp_net);
 545 }
 546
 547 struct xfrm_kmaddress {
 548         xfrm_address_t          local;
 549         xfrm_address_t          remote;
 550         u32                     reserved;
 551         u16                     family;
 552 };
 553
 554 struct xfrm_migrate {
 555         xfrm_address_t          old_daddr;
 556         xfrm_address_t          old_saddr;
 557         xfrm_address_t          new_daddr;
 558         xfrm_address_t          new_saddr;
 559         u8                      proto;
 560         u8                      mode;
 561         u16                     reserved;
 562         u32                     reqid;
 563         u16                     old_family;
 564         u16                     new_family;
 565 };
 566
 567 #define XFRM_KM_TIMEOUT                30
 568 /* what happened */
 569 #define XFRM_REPLAY_UPDATE      XFRM_AE_CR
 570 #define XFRM_REPLAY_TIMEOUT     XFRM_AE_CE
 571
 572 /* default aevent timeout in units of 100ms */
 573 #define XFRM_AE_ETIME                   10
 574 /* Async Event timer multiplier */
 575 #define XFRM_AE_ETH_M                   10
 576 /* default seq threshold size */
 577 #define XFRM_AE_SEQT_SIZE               2
 578
 579 struct xfrm_mgr {
 580         struct list_head        list;
 581         char                    *id;
 582         int                     (*notify)(struct xfrm_state *x, const struct km_event *c);
 583         int                     (*acquire)(struct xfrm_state *x, struct xfrm_tmpl *, struct xfrm_policy *xp);
 584         struct xfrm_policy      *(*compile_policy)(struct sock *sk, int opt, u8 *data, int len, int *dir);
 585         int                     (*new_mapping)(struct xfrm_state *x, xfrm_address_t *ipaddr, __be16 sport);
 586         int                     (*notify_policy)(struct xfrm_policy *x, int dir, const struct km_event *c);
 587         int                     (*report)(struct net *net, u8 proto, struct xfrm_selector *sel, xfrm_address_t *addr);
 588         int                     (*migrate)(const struct xfrm_selector *sel,
 589                                            u8 dir, u8 type,
 590                                            const struct xfrm_migrate *m,
 591                                            int num_bundles,
 592                                            const struct xfrm_kmaddress *k);
 593 };
 594
 595 extern int xfrm_register_km(struct xfrm_mgr *km);
 596 extern int xfrm_unregister_km(struct xfrm_mgr *km);
 597
 598 /*
 599  * This structure is used for the duration where packets are being
 600  * transformed by IPsec.  As soon as the packet leaves IPsec the
 601  * area beyond the generic IP part may be overwritten.
 602  */
 603 struct xfrm_skb_cb {
 604         union {
 605                 struct inet_skb_parm h4;
 606                 struct inet6_skb_parm h6;
 607         } header;
 608
 609         /* Sequence number for replay protection. */
 610         union {
 611                 struct {
 612                         __u32 low;
 613                         __u32 hi;
 614                 } output;
 615                 struct {
 616                         __be32 low;
 617                         __be32 hi;
 618                 } input;
 619         } seq;
 620 };
 621
 622 #define XFRM_SKB_CB(__skb) ((struct xfrm_skb_cb *)&((__skb)->cb[0]))
 623
 624 /*
 625  * This structure is used by the afinfo prepare_input/prepare_output functions
 626  * to transmit header information to the mode input/output functions.
 627  */
 628 struct xfrm_mode_skb_cb {
 629         union {
 630                 struct inet_skb_parm h4;
 631                 struct inet6_skb_parm h6;
 632         } header;
 633
 634         /* Copied from header for IPv4, always set to zero and DF for IPv6. */
 635         __be16 id;
 636         __be16 frag_off;
 637
 638         /* IP header length (excluding options or extension headers). */
 639         u8 ihl;
 640
 641         /* TOS for IPv4, class for IPv6. */
 642         u8 tos;
 643
 644         /* TTL for IPv4, hop limitfor IPv6. */
 645         u8 ttl;
 646
 647         /* Protocol for IPv4, NH for IPv6. */
 648         u8 protocol;
 649
 650         /* Option length for IPv4, zero for IPv6. */
 651         u8 optlen;
 652
 653         /* Used by IPv6 only, zero for IPv4. */
 654         u8 flow_lbl[3];
 655 };
 656
 657 #define XFRM_MODE_SKB_CB(__skb) ((struct xfrm_mode_skb_cb *)&((__skb)->cb[0]))
 658
 659 /*
 660  * This structure is used by the input processing to locate the SPI and
 661  * related information.
 662  */
 663 struct xfrm_spi_skb_cb {
 664         union {
 665                 struct inet_skb_parm h4;
 666                 struct inet6_skb_parm h6;
 667         } header;
 668
 669         unsigned int daddroff;
 670         unsigned int family;
 671 };
 672
 673 #define XFRM_SPI_SKB_CB(__skb) ((struct xfrm_spi_skb_cb *)&((__skb)->cb[0]))
 674
 675 /* Audit Information */
 676 struct xfrm_audit {
 677         u32     secid;
 678         kuid_t  loginuid;
 679         u32     sessionid;
 680 };
 681
 682 #ifdef CONFIG_AUDITSYSCALL
 683 static inline struct audit_buffer *xfrm_audit_start(const char *op)
 684 {
 685         struct audit_buffer *audit_buf = NULL;
 686
 687         if (audit_enabled == 0)
 688                 return NULL;
 689         audit_buf = audit_log_start(current->audit_context, GFP_ATOMIC,
 690                                     AUDIT_MAC_IPSEC_EVENT);
 691         if (audit_buf == NULL)
 692                 return NULL;
 693         audit_log_format(audit_buf, "op=%s", op);
 694         return audit_buf;
 695 }
 696
 697 static inline void xfrm_audit_helper_usrinfo(kuid_t auid, u32 ses, u32 secid,
 698                                              struct audit_buffer *audit_buf)
 699 {
 700         char *secctx;
 701         u32 secctx_len;
 702
 703         audit_log_format(audit_buf, " auid=%u ses=%u",
 704                          from_kuid(&init_user_ns, auid), ses);
 705         if (secid != 0 &&
 706             security_secid_to_secctx(secid, &secctx, &secctx_len) == 0) {
 707                 audit_log_format(audit_buf, " subj=%s", secctx);
 708                 security_release_secctx(secctx, secctx_len);
 709         } else
 710                 audit_log_task_context(audit_buf);
 711 }
 712
 713 extern void xfrm_audit_policy_add(struct xfrm_policy *xp, int result,
 714                                   kuid_t auid, u32 ses, u32 secid);
 715 extern void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
 716                                   kuid_t auid, u32 ses, u32 secid);
 717 extern void xfrm_audit_state_add(struct xfrm_state *x, int result,
 718                                  kuid_t auid, u32 ses, u32 secid);
 719 extern void xfrm_audit_state_delete(struct xfrm_state *x, int result,
 720                                     kuid_t auid, u32 ses, u32 secid);
 721 extern void xfrm_audit_state_replay_overflow(struct xfrm_state *x,
 722                                              struct sk_buff *skb);
 723 extern void xfrm_audit_state_replay(struct xfrm_state *x,
 724                                     struct sk_buff *skb, __be32 net_seq);
 725 extern void xfrm_audit_state_notfound_simple(struct sk_buff *skb, u16 family);
 726 extern void xfrm_audit_state_notfound(struct sk_buff *skb, u16 family,
 727                                       __be32 net_spi, __be32 net_seq);
 728 extern void xfrm_audit_state_icvfail(struct xfrm_state *x,
 729                                      struct sk_buff *skb, u8 proto);
 730 #else
 731
 732 static inline void xfrm_audit_policy_add(struct xfrm_policy *xp, int result,
 733                                   kuid_t auid, u32 ses, u32 secid)
 734 {
 735 }
 736
 737 static inline void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
 738                                   kuid_t auid, u32 ses, u32 secid)
 739 {
 740 }
 741
 742 static inline void xfrm_audit_state_add(struct xfrm_state *x, int result,
 743                                  kuid_t auid, u32 ses, u32 secid)
 744 {
 745 }
 746
 747 static inline void xfrm_audit_state_delete(struct xfrm_state *x, int result,
 748                                     kuid_t auid, u32 ses, u32 secid)
 749 {
 750 }
 751
 752 static inline void xfrm_audit_state_replay_overflow(struct xfrm_state *x,
 753                                              struct sk_buff *skb)
 754 {
 755 }
 756
 757 static inline void xfrm_audit_state_replay(struct xfrm_state *x,
 758                                            struct sk_buff *skb, __be32 net_seq)
 759 {
 760 }
 761
 762 static inline void xfrm_audit_state_notfound_simple(struct sk_buff *skb,
 763                                       u16 family)
 764 {
 765 }
 766
 767 static inline void xfrm_audit_state_notfound(struct sk_buff *skb, u16 family,
 768                                       __be32 net_spi, __be32 net_seq)
 769 {
 770 }
 771
 772 static inline void xfrm_audit_state_icvfail(struct xfrm_state *x,
 773                                      struct sk_buff *skb, u8 proto)
 774 {
 775 }
 776 #endif /* CONFIG_AUDITSYSCALL */
 777
 778 static inline void xfrm_pol_hold(struct xfrm_policy *policy)
 779 {
 780         if (likely(policy != NULL))
 781                 atomic_inc(&policy->refcnt);
 782 }
 783
 784 extern void xfrm_policy_destroy(struct xfrm_policy *policy);
 785
 786 static inline void xfrm_pol_put(struct xfrm_policy *policy)
 787 {
 788         if (atomic_dec_and_test(&policy->refcnt))
 789                 xfrm_policy_destroy(policy);
 790 }
 791
 792 static inline void xfrm_pols_put(struct xfrm_policy **pols, int npols)
 793 {
 794         int i;
 795         for (i = npols - 1; i >= 0; --i)
 796                 xfrm_pol_put(pols[i]);
 797 }
 798
 799 extern void __xfrm_state_destroy(struct xfrm_state *);
 800
 801 static inline void __xfrm_state_put(struct xfrm_state *x)
 802 {
 803         atomic_dec(&x->refcnt);
 804 }
 805
 806 static inline void xfrm_state_put(struct xfrm_state *x)
 807 {
 808         if (atomic_dec_and_test(&x->refcnt))
 809                 __xfrm_state_destroy(x);
 810 }
 811
 812 static inline void xfrm_state_hold(struct xfrm_state *x)
 813 {
 814         atomic_inc(&x->refcnt);
 815 }
 816
 817 static inline bool addr_match(const void *token1, const void *token2,
 818                               int prefixlen)
 819 {
 820         const __be32 *a1 = token1;
 821         const __be32 *a2 = token2;
 822         int pdw;
 823         int pbi;
 824
 825         pdw = prefixlen >> 5;     /* num of whole u32 in prefix */
 826         pbi = prefixlen &  0x1f;  /* num of bits in incomplete u32 in prefix */
 827
 828         if (pdw)
 829                 if (memcmp(a1, a2, pdw << 2))
 830                         return false;
 831
 832         if (pbi) {
 833                 __be32 mask;
 834
 835                 mask = htonl((0xffffffff) << (32 - pbi));
 836
 837                 if ((a1[pdw] ^ a2[pdw]) & mask)
 838                         return false;
 839         }
 840
 841         return true;
 842 }
 843
 844 static inline bool addr4_match(__be32 a1, __be32 a2, u8 prefixlen)
 845 {
 846         /* C99 6.5.7 (3): u32 << 32 is undefined behaviour */
 847         if (prefixlen == 0)
 848                 return true;
 849         return !((a1 ^ a2) & htonl(0xFFFFFFFFu << (32 - prefixlen)));
 850 }
 851
 852 static __inline__
 853 __be16 xfrm_flowi_sport(const struct flowi *fl, const union flowi_uli *uli)
 854 {
 855         __be16 port;
 856         switch(fl->flowi_proto) {
 857         case IPPROTO_TCP:
 858         case IPPROTO_UDP:
 859         case IPPROTO_UDPLITE:
 860         case IPPROTO_SCTP:
 861                 port = uli->ports.sport;
 862                 break;
 863         case IPPROTO_ICMP:
 864         case IPPROTO_ICMPV6:
 865                 port = htons(uli->icmpt.type);
 866                 break;
 867         case IPPROTO_MH:
 868                 port = htons(uli->mht.type);
 869                 break;
 870         case IPPROTO_GRE:
 871                 port = htons(ntohl(uli->gre_key) >> 16);
 872                 break;
 873         default:
 874                 port = 0;       /*XXX*/
 875         }
 876         return port;
 877 }
 878
 879 static __inline__
 880 __be16 xfrm_flowi_dport(const struct flowi *fl, const union flowi_uli *uli)
 881 {
 882         __be16 port;
 883         switch(fl->flowi_proto) {
 884         case IPPROTO_TCP:
 885         case IPPROTO_UDP:
 886         case IPPROTO_UDPLITE:
 887         case IPPROTO_SCTP:
 888                 port = uli->ports.dport;
 889                 break;
 890         case IPPROTO_ICMP:
 891         case IPPROTO_ICMPV6:
 892                 port = htons(uli->icmpt.code);
 893                 break;
 894         case IPPROTO_GRE:
 895                 port = htons(ntohl(uli->gre_key) & 0xffff);
 896                 break;
 897         default:
 898                 port = 0;       /*XXX*/
 899         }
 900         return port;
 901 }
 902
 903 extern bool xfrm_selector_match(const struct xfrm_selector *sel,
 904                                 const struct flowi *fl,
 905                                 unsigned short family);
 906
 907 #ifdef CONFIG_SECURITY_NETWORK_XFRM
 908 /*      If neither has a context --> match
 909  *      Otherwise, both must have a context and the sids, doi, alg must match
 910  */
 911 static inline bool xfrm_sec_ctx_match(struct xfrm_sec_ctx *s1, struct xfrm_sec_ctx *s2)
 912 {
 913         return ((!s1 && !s2) ||
 914                 (s1 && s2 &&
 915                  (s1->ctx_sid == s2->ctx_sid) &&
 916                  (s1->ctx_doi == s2->ctx_doi) &&
 917                  (s1->ctx_alg == s2->ctx_alg)));
 918 }
 919 #else
 920 static inline bool xfrm_sec_ctx_match(struct xfrm_sec_ctx *s1, struct xfrm_sec_ctx *s2)
 921 {
 922         return true;
 923 }
 924 #endif
 925
 926 /* A struct encoding bundle of transformations to apply to some set of flow.
 927  *
 928  * dst->child points to the next element of bundle.
 929  * dst->xfrm  points to an instanse of transformer.
 930  *
 931  * Due to unfortunate limitations of current routing cache, which we
 932  * have no time to fix, it mirrors struct rtable and bound to the same
 933  * routing key, including saddr,daddr. However, we can have many of
 934  * bundles differing by session id. All the bundles grow from a parent
 935  * policy rule.
 936  */
 937 struct xfrm_dst {
 938         union {
 939                 struct dst_entry        dst;
 940                 struct rtable           rt;
 941                 struct rt6_info         rt6;
 942         } u;
 943         struct dst_entry *route;
 944         struct flow_cache_object flo;
 945         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
 946         int num_pols, num_xfrms;
 947 #ifdef CONFIG_XFRM_SUB_POLICY
 948         struct flowi *origin;
 949         struct xfrm_selector *partner;
 950 #endif
 951         u32 xfrm_genid;
 952         u32 policy_genid;
 953         u32 route_mtu_cached;
 954         u32 child_mtu_cached;
 955         u32 route_cookie;
 956         u32 path_cookie;
 957 };
 958
 959 #ifdef CONFIG_XFRM
 960 static inline void xfrm_dst_destroy(struct xfrm_dst *xdst)
 961 {
 962         xfrm_pols_put(xdst->pols, xdst->num_pols);
 963         dst_release(xdst->route);
 964         if (likely(xdst->u.dst.xfrm))
 965                 xfrm_state_put(xdst->u.dst.xfrm);
 966 #ifdef CONFIG_XFRM_SUB_POLICY
 967         kfree(xdst->origin);
 968         xdst->origin = NULL;
 969         kfree(xdst->partner);
 970         xdst->partner = NULL;
 971 #endif
 972 }
 973 #endif
 974
 975 extern void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev);
 976
 977 struct sec_path {
 978         atomic_t                refcnt;
 979         int                     len;
 980         struct xfrm_state       *xvec[XFRM_MAX_DEPTH];
 981 };
 982
 983 static inline int secpath_exists(struct sk_buff *skb)
 984 {
 985 #ifdef CONFIG_XFRM
 986         return skb->sp != NULL;
 987 #else
 988         return 0;
 989 #endif
 990 }
 991
 992 static inline struct sec_path *
 993 secpath_get(struct sec_path *sp)
 994 {
 995         if (sp)
 996                 atomic_inc(&sp->refcnt);
 997         return sp;
 998 }
 999
1000 extern void __secpath_destroy(struct sec_path *sp);
1001
1002 static inline void
1003 secpath_put(struct sec_path *sp)
1004 {
1005         if (sp && atomic_dec_and_test(&sp->refcnt))
1006                 __secpath_destroy(sp);
1007 }
1008
1009 extern struct sec_path *secpath_dup(struct sec_path *src);
1010
1011 static inline void
1012 secpath_reset(struct sk_buff *skb)
1013 {
1014 #ifdef CONFIG_XFRM
1015         secpath_put(skb->sp);
1016         skb->sp = NULL;
1017 #endif
1018 }
1019
1020 static inline int
1021 xfrm_addr_any(const xfrm_address_t *addr, unsigned short family)
1022 {
1023         switch (family) {
1024         case AF_INET:
1025                 return addr->a4 == 0;
1026         case AF_INET6:
1027                 return ipv6_addr_any((struct in6_addr *)&addr->a6);
1028         }
1029         return 0;
1030 }
1031
1032 static inline int
1033 __xfrm4_state_addr_cmp(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x)
1034 {
1035         return  (tmpl->saddr.a4 &&
1036                  tmpl->saddr.a4 != x->props.saddr.a4);
1037 }
1038
1039 static inline int
1040 __xfrm6_state_addr_cmp(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x)
1041 {
1042         return  (!ipv6_addr_any((struct in6_addr*)&tmpl->saddr) &&
1043                  !ipv6_addr_equal((struct in6_addr *)&tmpl->saddr, (struct in6_addr*)&x->props.saddr));
1044 }
1045
1046 static inline int
1047 xfrm_state_addr_cmp(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, unsigned short family)
1048 {
1049         switch (family) {
1050         case AF_INET:
1051                 return __xfrm4_state_addr_cmp(tmpl, x);
1052         case AF_INET6:
1053                 return __xfrm6_state_addr_cmp(tmpl, x);
1054         }
1055         return !0;
1056 }
1057
1058 #ifdef CONFIG_XFRM
1059 extern int __xfrm_policy_check(struct sock *, int dir, struct sk_buff *skb, unsigned short family);
1060
1061 static inline int __xfrm_policy_check2(struct sock *sk, int dir,
1062                                        struct sk_buff *skb,
1063                                        unsigned int family, int reverse)
1064 {
1065         struct net *net = dev_net(skb->dev);
1066         int ndir = dir | (reverse ? XFRM_POLICY_MASK + 1 : 0);
1067
1068         if (sk && sk->sk_policy[XFRM_POLICY_IN])
1069                 return __xfrm_policy_check(sk, ndir, skb, family);
1070
1071         return  (!net->xfrm.policy_count[dir] && !skb->sp) ||
1072                 (skb_dst(skb)->flags & DST_NOPOLICY) ||
1073                 __xfrm_policy_check(sk, ndir, skb, family);
1074 }
1075
1076 static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
1077 {
1078         return __xfrm_policy_check2(sk, dir, skb, family, 0);
1079 }
1080
1081 static inline int xfrm4_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
1082 {
1083         return xfrm_policy_check(sk, dir, skb, AF_INET);
1084 }
1085
1086 static inline int xfrm6_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
1087 {
1088         return xfrm_policy_check(sk, dir, skb, AF_INET6);
1089 }
1090
1091 static inline int xfrm4_policy_check_reverse(struct sock *sk, int dir,
1092                                              struct sk_buff *skb)
1093 {
1094         return __xfrm_policy_check2(sk, dir, skb, AF_INET, 1);
1095 }
1096
1097 static inline int xfrm6_policy_check_reverse(struct sock *sk, int dir,
1098                                              struct sk_buff *skb)
1099 {
1100         return __xfrm_policy_check2(sk, dir, skb, AF_INET6, 1);
1101 }
1102
1103 extern int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
1104                                  unsigned int family, int reverse);
1105
1106 static inline int xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
1107                                       unsigned int family)
1108 {
1109         return __xfrm_decode_session(skb, fl, family, 0);
1110 }
1111
1112 static inline int xfrm_decode_session_reverse(struct sk_buff *skb,
1113                                               struct flowi *fl,
1114                                               unsigned int family)
1115 {
1116         return __xfrm_decode_session(skb, fl, family, 1);
1117 }
1118
1119 extern int __xfrm_route_forward(struct sk_buff *skb, unsigned short family);
1120
1121 static inline int xfrm_route_forward(struct sk_buff *skb, unsigned short family)
1122 {
1123         struct net *net = dev_net(skb->dev);
1124
1125         return  !net->xfrm.policy_count[XFRM_POLICY_OUT] ||
1126                 (skb_dst(skb)->flags & DST_NOXFRM) ||
1127                 __xfrm_route_forward(skb, family);
1128 }
1129
1130 static inline int xfrm4_route_forward(struct sk_buff *skb)
1131 {
1132         return xfrm_route_forward(skb, AF_INET);
1133 }
1134
1135 static inline int xfrm6_route_forward(struct sk_buff *skb)
1136 {
1137         return xfrm_route_forward(skb, AF_INET6);
1138 }
1139
1140 extern int __xfrm_sk_clone_policy(struct sock *sk);
1141
1142 static inline int xfrm_sk_clone_policy(struct sock *sk)
1143 {
1144         if (unlikely(sk->sk_policy[0] || sk->sk_policy[1]))
1145                 return __xfrm_sk_clone_policy(sk);
1146         return 0;
1147 }
1148
1149 extern int xfrm_policy_delete(struct xfrm_policy *pol, int dir);
1150
1151 static inline void xfrm_sk_free_policy(struct sock *sk)
1152 {
1153         if (unlikely(sk->sk_policy[0] != NULL)) {
1154                 xfrm_policy_delete(sk->sk_policy[0], XFRM_POLICY_MAX);
1155                 sk->sk_policy[0] = NULL;
1156         }
1157         if (unlikely(sk->sk_policy[1] != NULL)) {
1158                 xfrm_policy_delete(sk->sk_policy[1], XFRM_POLICY_MAX+1);
1159                 sk->sk_policy[1] = NULL;
1160         }
1161 }
1162
1163 #else
1164
1165 static inline void xfrm_sk_free_policy(struct sock *sk) {}
1166 static inline int xfrm_sk_clone_policy(struct sock *sk) { return 0; }
1167 static inline int xfrm6_route_forward(struct sk_buff *skb) { return 1; }
1168 static inline int xfrm4_route_forward(struct sk_buff *skb) { return 1; }
1169 static inline int xfrm6_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
1170 {
1171         return 1;
1172 }
1173 static inline int xfrm4_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
1174 {
1175         return 1;
1176 }
1177 static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
1178 {
1179         return 1;
1180 }
1181 static inline int xfrm_decode_session_reverse(struct sk_buff *skb,
1182                                               struct flowi *fl,
1183                                               unsigned int family)
1184 {
1185         return -ENOSYS;
1186 }
1187 static inline int xfrm4_policy_check_reverse(struct sock *sk, int dir,
1188                                              struct sk_buff *skb)
1189 {
1190         return 1;
1191 }
1192 static inline int xfrm6_policy_check_reverse(struct sock *sk, int dir,
1193                                              struct sk_buff *skb)
1194 {
1195         return 1;
1196 }
1197 #endif
1198
1199 static __inline__
1200 xfrm_address_t *xfrm_flowi_daddr(const struct flowi *fl, unsigned short family)
1201 {
1202         switch (family){
1203         case AF_INET:
1204                 return (xfrm_address_t *)&fl->u.ip4.daddr;
1205         case AF_INET6:
1206                 return (xfrm_address_t *)&fl->u.ip6.daddr;
1207         }
1208         return NULL;
1209 }
1210
1211 static __inline__
1212 xfrm_address_t *xfrm_flowi_saddr(const struct flowi *fl, unsigned short family)
1213 {
1214         switch (family){
1215         case AF_INET:
1216                 return (xfrm_address_t *)&fl->u.ip4.saddr;
1217         case AF_INET6:
1218                 return (xfrm_address_t *)&fl->u.ip6.saddr;
1219         }
1220         return NULL;
1221 }
1222
1223 static __inline__
1224 void xfrm_flowi_addr_get(const struct flowi *fl,
1225                          xfrm_address_t *saddr, xfrm_address_t *daddr,
1226                          unsigned short family)
1227 {
1228         switch(family) {
1229         case AF_INET:
1230                 memcpy(&saddr->a4, &fl->u.ip4.saddr, sizeof(saddr->a4));
1231                 memcpy(&daddr->a4, &fl->u.ip4.daddr, sizeof(daddr->a4));
1232                 break;
1233         case AF_INET6:
1234                 *(struct in6_addr *)saddr->a6 = fl->u.ip6.saddr;
1235                 *(struct in6_addr *)daddr->a6 = fl->u.ip6.daddr;
1236                 break;
1237         }
1238 }
1239
1240 static __inline__ int
1241 __xfrm4_state_addr_check(const struct xfrm_state *x,
1242                          const xfrm_address_t *daddr, const xfrm_address_t *saddr)
1243 {
1244         if (daddr->a4 == x->id.daddr.a4 &&
1245             (saddr->a4 == x->props.saddr.a4 || !saddr->a4 || !x->props.saddr.a4))
1246                 return 1;
1247         return 0;
1248 }
1249
1250 static __inline__ int
1251 __xfrm6_state_addr_check(const struct xfrm_state *x,
1252                          const xfrm_address_t *daddr, const xfrm_address_t *saddr)
1253 {
1254         if (ipv6_addr_equal((struct in6_addr *)daddr, (struct in6_addr *)&x->id.daddr) &&
1255             (ipv6_addr_equal((struct in6_addr *)saddr, (struct in6_addr *)&x->props.saddr) ||
1256              ipv6_addr_any((struct in6_addr *)saddr) ||
1257              ipv6_addr_any((struct in6_addr *)&x->props.saddr)))
1258                 return 1;
1259         return 0;
1260 }
1261
1262 static __inline__ int
1263 xfrm_state_addr_check(const struct xfrm_state *x,
1264                       const xfrm_address_t *daddr, const xfrm_address_t *saddr,
1265                       unsigned short family)
1266 {
1267         switch (family) {
1268         case AF_INET:
1269                 return __xfrm4_state_addr_check(x, daddr, saddr);
1270         case AF_INET6:
1271                 return __xfrm6_state_addr_check(x, daddr, saddr);
1272         }
1273         return 0;
1274 }
1275
1276 static __inline__ int
1277 xfrm_state_addr_flow_check(const struct xfrm_state *x, const struct flowi *fl,
1278                            unsigned short family)
1279 {
1280         switch (family) {
1281         case AF_INET:
1282                 return __xfrm4_state_addr_check(x,
1283                                                 (const xfrm_address_t *)&fl->u.ip4.daddr,
1284                                                 (const xfrm_address_t *)&fl->u.ip4.saddr);
1285         case AF_INET6:
1286                 return __xfrm6_state_addr_check(x,
1287                                                 (const xfrm_address_t *)&fl->u.ip6.daddr,
1288                                                 (const xfrm_address_t *)&fl->u.ip6.saddr);
1289         }
1290         return 0;
1291 }
1292
1293 static inline int xfrm_state_kern(const struct xfrm_state *x)
1294 {
1295         return atomic_read(&x->tunnel_users);
1296 }
1297
1298 static inline int xfrm_id_proto_match(u8 proto, u8 userproto)
1299 {
1300         return (!userproto || proto == userproto ||
1301                 (userproto == IPSEC_PROTO_ANY && (proto == IPPROTO_AH ||
1302                                                   proto == IPPROTO_ESP ||
1303                                                   proto == IPPROTO_COMP)));
1304 }
1305
1306 /*
1307  * xfrm algorithm information
1308  */
1309 struct xfrm_algo_aead_info {
1310         u16 icv_truncbits;
1311 };
1312
1313 struct xfrm_algo_auth_info {
1314         u16 icv_truncbits;
1315         u16 icv_fullbits;
1316 };
1317
1318 struct xfrm_algo_encr_info {
1319         u16 blockbits;
1320         u16 defkeybits;
1321 };
1322
1323 struct xfrm_algo_comp_info {
1324         u16 threshold;
1325 };
1326
1327 struct xfrm_algo_desc {
1328         char *name;
1329         char *compat;
1330         u8 available:1;
1331         u8 pfkey_supported:1;
1332         union {
1333                 struct xfrm_algo_aead_info aead;
1334                 struct xfrm_algo_auth_info auth;
1335                 struct xfrm_algo_encr_info encr;
1336                 struct xfrm_algo_comp_info comp;
1337         } uinfo;
1338         struct sadb_alg desc;
1339 };
1340
1341 /* XFRM tunnel handlers.  */
1342 struct xfrm_tunnel {
1343         int (*handler)(struct sk_buff *skb);
1344         int (*err_handler)(struct sk_buff *skb, u32 info);
1345
1346         struct xfrm_tunnel __rcu *next;
1347         int priority;
1348 };
1349
1350 struct xfrm6_tunnel {
1351         int (*handler)(struct sk_buff *skb);
1352         int (*err_handler)(struct sk_buff *skb, struct inet6_skb_parm *opt,
1353                            u8 type, u8 code, int offset, __be32 info);
1354         struct xfrm6_tunnel __rcu *next;
1355         int priority;
1356 };
1357
1358 extern void xfrm_init(void);
1359 extern void xfrm4_init(void);
1360 extern int xfrm_state_init(struct net *net);
1361 extern void xfrm_state_fini(struct net *net);
1362 extern void xfrm4_state_init(void);
1363 #ifdef CONFIG_XFRM
1364 extern int xfrm6_init(void);
1365 extern void xfrm6_fini(void);
1366 extern int xfrm6_state_init(void);
1367 extern void xfrm6_state_fini(void);
1368 #else
1369 static inline int xfrm6_init(void)
1370 {
1371         return 0;
1372 }
1373 static inline void xfrm6_fini(void)
1374 {
1375         ;
1376 }
1377 #endif
1378
1379 #ifdef CONFIG_XFRM_STATISTICS
1380 extern int xfrm_proc_init(struct net *net);
1381 extern void xfrm_proc_fini(struct net *net);
1382 #endif
1383
1384 extern int xfrm_sysctl_init(struct net *net);
1385 #ifdef CONFIG_SYSCTL
1386 extern void xfrm_sysctl_fini(struct net *net);
1387 #else
1388 static inline void xfrm_sysctl_fini(struct net *net)
1389 {
1390 }
1391 #endif
1392
1393 extern void xfrm_state_walk_init(struct xfrm_state_walk *walk, u8 proto);
1394 extern int xfrm_state_walk(struct net *net, struct xfrm_state_walk *walk,
1395                            int (*func)(struct xfrm_state *, int, void*), void *);
1396 extern void xfrm_state_walk_done(struct xfrm_state_walk *walk);
1397 extern struct xfrm_state *xfrm_state_alloc(struct net *net);
1398 extern struct xfrm_state *xfrm_state_find(const xfrm_address_t *daddr,
1399                                           const xfrm_address_t *saddr,
1400                                           const struct flowi *fl,
1401                                           struct xfrm_tmpl *tmpl,
1402                                           struct xfrm_policy *pol, int *err,
1403                                           unsigned short family);
1404 extern struct xfrm_state *xfrm_stateonly_find(struct net *net, u32 mark,
1405                                                xfrm_address_t *daddr,
1406                                                xfrm_address_t *saddr,
1407                                                unsigned short family,
1408                                                u8 mode, u8 proto, u32 reqid);
1409 extern int xfrm_state_check_expire(struct xfrm_state *x);
1410 extern void xfrm_state_insert(struct xfrm_state *x);
1411 extern int xfrm_state_add(struct xfrm_state *x);
1412 extern int xfrm_state_update(struct xfrm_state *x);
1413 extern struct xfrm_state *xfrm_state_lookup(struct net *net, u32 mark,
1414                                             const xfrm_address_t *daddr, __be32 spi,
1415                                             u8 proto, unsigned short family);
1416 extern struct xfrm_state *xfrm_state_lookup_byaddr(struct net *net, u32 mark,
1417                                                    const xfrm_address_t *daddr,
1418                                                    const xfrm_address_t *saddr,
1419                                                    u8 proto,
1420                                                    unsigned short family);
1421 #ifdef CONFIG_XFRM_SUB_POLICY
1422 extern int xfrm_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src,
1423                           int n, unsigned short family);
1424 extern int xfrm_state_sort(struct xfrm_state **dst, struct xfrm_state **src,
1425                            int n, unsigned short family);
1426 #else
1427 static inline int xfrm_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src,
1428                                  int n, unsigned short family)
1429 {
1430         return -ENOSYS;
1431 }
1432
1433 static inline int xfrm_state_sort(struct xfrm_state **dst, struct xfrm_state **src,
1434                                   int n, unsigned short family)
1435 {
1436         return -ENOSYS;
1437 }
1438 #endif
1439
1440 struct xfrmk_sadinfo {
1441         u32 sadhcnt; /* current hash bkts */
1442         u32 sadhmcnt; /* max allowed hash bkts */
1443         u32 sadcnt; /* current running count */
1444 };
1445
1446 struct xfrmk_spdinfo {
1447         u32 incnt;
1448         u32 outcnt;
1449         u32 fwdcnt;
1450         u32 inscnt;
1451         u32 outscnt;
1452         u32 fwdscnt;
1453         u32 spdhcnt;
1454         u32 spdhmcnt;
1455 };
1456
1457 extern struct xfrm_state *xfrm_find_acq_byseq(struct net *net, u32 mark,
1458                                               u32 seq);
1459 extern int xfrm_state_delete(struct xfrm_state *x);
1460 extern int xfrm_state_flush(struct net *net, u8 proto, struct xfrm_audit *audit_info);
1461 extern void xfrm_sad_getinfo(struct net *net, struct xfrmk_sadinfo *si);
1462 extern void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si);
1463 extern u32 xfrm_replay_seqhi(struct xfrm_state *x, __be32 net_seq);
1464 extern int xfrm_init_replay(struct xfrm_state *x);
1465 extern int xfrm_state_mtu(struct xfrm_state *x, int mtu);
1466 extern int __xfrm_init_state(struct xfrm_state *x, bool init_replay);
1467 extern int xfrm_init_state(struct xfrm_state *x);
1468 extern int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb);
1469 extern int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi,
1470                       int encap_type);
1471 extern int xfrm_input_resume(struct sk_buff *skb, int nexthdr);
1472 extern int xfrm_output_resume(struct sk_buff *skb, int err);
1473 extern int xfrm_output(struct sk_buff *skb);
1474 extern int xfrm_inner_extract_output(struct xfrm_state *x, struct sk_buff *skb);
1475 extern int xfrm4_extract_header(struct sk_buff *skb);
1476 extern int xfrm4_extract_input(struct xfrm_state *x, struct sk_buff *skb);
1477 extern int xfrm4_rcv_encap(struct sk_buff *skb, int nexthdr, __be32 spi,
1478                            int encap_type);
1479 extern int xfrm4_transport_finish(struct sk_buff *skb, int async);
1480 extern int xfrm4_rcv(struct sk_buff *skb);
1481
1482 static inline int xfrm4_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi)
1483 {
1484         return xfrm4_rcv_encap(skb, nexthdr, spi, 0);
1485 }
1486
1487 extern int xfrm4_extract_output(struct xfrm_state *x, struct sk_buff *skb);
1488 extern int xfrm4_prepare_output(struct xfrm_state *x, struct sk_buff *skb);
1489 extern int xfrm4_output(struct sk_buff *skb);
1490 extern int xfrm4_output_finish(struct sk_buff *skb);
1491 extern int xfrm4_tunnel_register(struct xfrm_tunnel *handler, unsigned short family);
1492 extern int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler, unsigned short family);
1493 extern int xfrm4_mode_tunnel_input_register(struct xfrm_tunnel *handler);
1494 extern int xfrm4_mode_tunnel_input_deregister(struct xfrm_tunnel *handler);
1495 extern int xfrm6_extract_header(struct sk_buff *skb);
1496 extern int xfrm6_extract_input(struct xfrm_state *x, struct sk_buff *skb);
1497 extern int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi);
1498 extern int xfrm6_transport_finish(struct sk_buff *skb, int async);
1499 extern int xfrm6_rcv(struct sk_buff *skb);
1500 extern int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
1501                             xfrm_address_t *saddr, u8 proto);
1502 extern int xfrm6_tunnel_register(struct xfrm6_tunnel *handler, unsigned short family);
1503 extern int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler, unsigned short family);
1504 extern __be32 xfrm6_tunnel_alloc_spi(struct net *net, xfrm_address_t *saddr);
1505 extern __be32 xfrm6_tunnel_spi_lookup(struct net *net, const xfrm_address_t *saddr);
1506 extern int xfrm6_extract_output(struct xfrm_state *x, struct sk_buff *skb);
1507 extern int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb);
1508 extern int xfrm6_output(struct sk_buff *skb);
1509 extern int xfrm6_output_finish(struct sk_buff *skb);
1510 extern int xfrm6_find_1stfragopt(struct xfrm_state *x, struct sk_buff *skb,
1511                                  u8 **prevhdr);
1512
1513 #ifdef CONFIG_XFRM
1514 extern int xfrm4_udp_encap_rcv(struct sock *sk, struct sk_buff *skb);
1515 extern int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen);
1516 #else
1517 static inline int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen)
1518 {
1519         return -ENOPROTOOPT;
1520 }
1521
1522 static inline int xfrm4_udp_encap_rcv(struct sock *sk, struct sk_buff *skb)
1523 {
1524         /* should not happen */
1525         kfree_skb(skb);
1526         return 0;
1527 }
1528 #endif
1529
1530 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp);
1531
1532 extern void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type);
1533 extern int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
1534         int (*func)(struct xfrm_policy *, int, int, void*), void *);
1535 extern void xfrm_policy_walk_done(struct xfrm_policy_walk *walk);
1536 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl);
1537 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark,
1538                                           u8 type, int dir,
1539                                           struct xfrm_selector *sel,
1540                                           struct xfrm_sec_ctx *ctx, int delete,
1541                                           int *err);
1542 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8, int dir, u32 id, int delete, int *err);
1543 int xfrm_policy_flush(struct net *net, u8 type, struct xfrm_audit *audit_info);
1544 u32 xfrm_get_acqseq(void);
1545 extern int xfrm_alloc_spi(struct xfrm_state *x, u32 minspi, u32 maxspi);
1546 struct xfrm_state *xfrm_find_acq(struct net *net, struct xfrm_mark *mark,
1547                                  u8 mode, u32 reqid, u8 proto,
1548                                  const xfrm_address_t *daddr,
1549                                  const xfrm_address_t *saddr, int create,
1550                                  unsigned short family);
1551 extern int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol);
1552
1553 #ifdef CONFIG_XFRM_MIGRATE
1554 extern int km_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
1555                       const struct xfrm_migrate *m, int num_bundles,
1556                       const struct xfrm_kmaddress *k);
1557 extern struct xfrm_state * xfrm_migrate_state_find(struct xfrm_migrate *m);
1558 extern struct xfrm_state * xfrm_state_migrate(struct xfrm_state *x,
1559                                               struct xfrm_migrate *m);
1560 extern int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
1561                         struct xfrm_migrate *m, int num_bundles,
1562                         struct xfrm_kmaddress *k);
1563 #endif
1564
1565 extern int km_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr, __be16 sport);
1566 extern void km_policy_expired(struct xfrm_policy *pol, int dir, int hard, u32 portid);
1567 extern int km_report(struct net *net, u8 proto, struct xfrm_selector *sel, xfrm_address_t *addr);
1568
1569 extern void xfrm_input_init(void);
1570 extern int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq);
1571
1572 extern void xfrm_probe_algs(void);
1573 extern int xfrm_count_pfkey_auth_supported(void);
1574 extern int xfrm_count_pfkey_enc_supported(void);
1575 extern struct xfrm_algo_desc *xfrm_aalg_get_byidx(unsigned int idx);
1576 extern struct xfrm_algo_desc *xfrm_ealg_get_byidx(unsigned int idx);
1577 extern struct xfrm_algo_desc *xfrm_aalg_get_byid(int alg_id);
1578 extern struct xfrm_algo_desc *xfrm_ealg_get_byid(int alg_id);
1579 extern struct xfrm_algo_desc *xfrm_calg_get_byid(int alg_id);
1580 extern struct xfrm_algo_desc *xfrm_aalg_get_byname(const char *name, int probe);
1581 extern struct xfrm_algo_desc *xfrm_ealg_get_byname(const char *name, int probe);
1582 extern struct xfrm_algo_desc *xfrm_calg_get_byname(const char *name, int probe);
1583 extern struct xfrm_algo_desc *xfrm_aead_get_byname(const char *name, int icv_len,
1584                                                    int probe);
1585
1586 static inline bool xfrm6_addr_equal(const xfrm_address_t *a,
1587                                     const xfrm_address_t *b)
1588 {
1589         return ipv6_addr_equal((const struct in6_addr *)a,
1590                                (const struct in6_addr *)b);
1591 }
1592
1593 static inline bool xfrm_addr_equal(const xfrm_address_t *a,
1594                                    const xfrm_address_t *b,
1595                                    sa_family_t family)
1596 {
1597         switch (family) {
1598         default:
1599         case AF_INET:
1600                 return ((__force u32)a->a4 ^ (__force u32)b->a4) == 0;
1601         case AF_INET6:
1602                 return xfrm6_addr_equal(a, b);
1603         }
1604 }
1605
1606 static inline int xfrm_policy_id2dir(u32 index)
1607 {
1608         return index & 7;
1609 }
1610
1611 #ifdef CONFIG_XFRM
1612 static inline int xfrm_aevent_is_on(struct net *net)
1613 {
1614         struct sock *nlsk;
1615         int ret = 0;
1616
1617         rcu_read_lock();
1618         nlsk = rcu_dereference(net->xfrm.nlsk);
1619         if (nlsk)
1620                 ret = netlink_has_listeners(nlsk, XFRMNLGRP_AEVENTS);
1621         rcu_read_unlock();
1622         return ret;
1623 }
1624 #endif
1625
1626 static inline int xfrm_alg_len(const struct xfrm_algo *alg)
1627 {
1628         return sizeof(*alg) + ((alg->alg_key_len + 7) / 8);
1629 }
1630
1631 static inline int xfrm_alg_auth_len(const struct xfrm_algo_auth *alg)
1632 {
1633         return sizeof(*alg) + ((alg->alg_key_len + 7) / 8);
1634 }
1635
1636 static inline int xfrm_replay_state_esn_len(struct xfrm_replay_state_esn *replay_esn)
1637 {
1638         return sizeof(*replay_esn) + replay_esn->bmp_len * sizeof(__u32);
1639 }
1640
1641 #ifdef CONFIG_XFRM_MIGRATE
1642 static inline int xfrm_replay_clone(struct xfrm_state *x,
1643                                      struct xfrm_state *orig)
1644 {
1645         x->replay_esn = kzalloc(xfrm_replay_state_esn_len(orig->replay_esn),
1646                                 GFP_KERNEL);
1647         if (!x->replay_esn)
1648                 return -ENOMEM;
1649
1650         x->replay_esn->bmp_len = orig->replay_esn->bmp_len;
1651         x->replay_esn->replay_window = orig->replay_esn->replay_window;
1652
1653         x->preplay_esn = kmemdup(x->replay_esn,
1654                                  xfrm_replay_state_esn_len(x->replay_esn),
1655                                  GFP_KERNEL);
1656         if (!x->preplay_esn) {
1657                 kfree(x->replay_esn);
1658                 return -ENOMEM;
1659         }
1660
1661         return 0;
1662 }
1663
1664 static inline struct xfrm_algo *xfrm_algo_clone(struct xfrm_algo *orig)
1665 {
1666         return kmemdup(orig, xfrm_alg_len(orig), GFP_KERNEL);
1667 }
1668
1669 static inline struct xfrm_algo_auth *xfrm_algo_auth_clone(struct xfrm_algo_auth *orig)
1670 {
1671         return kmemdup(orig, xfrm_alg_auth_len(orig), GFP_KERNEL);
1672 }
1673
1674 static inline void xfrm_states_put(struct xfrm_state **states, int n)
1675 {
1676         int i;
1677         for (i = 0; i < n; i++)
1678                 xfrm_state_put(*(states + i));
1679 }
1680
1681 static inline void xfrm_states_delete(struct xfrm_state **states, int n)
1682 {
1683         int i;
1684         for (i = 0; i < n; i++)
1685                 xfrm_state_delete(*(states + i));
1686 }
1687 #endif
1688
1689 #ifdef CONFIG_XFRM
1690 static inline struct xfrm_state *xfrm_input_state(struct sk_buff *skb)
1691 {
1692         return skb->sp->xvec[skb->sp->len - 1];
1693 }
1694 #endif
1695
1696 static inline int xfrm_mark_get(struct nlattr **attrs, struct xfrm_mark *m)
1697 {
1698         if (attrs[XFRMA_MARK])
1699                 memcpy(m, nla_data(attrs[XFRMA_MARK]), sizeof(struct xfrm_mark));
1700         else
1701                 m->v = m->m = 0;
1702
1703         return m->v & m->m;
1704 }
1705
1706 static inline int xfrm_mark_put(struct sk_buff *skb, const struct xfrm_mark *m)
1707 {
1708         int ret = 0;
1709
1710         if (m->m | m->v)
1711                 ret = nla_put(skb, XFRMA_MARK, sizeof(struct xfrm_mark), m);
1712         return ret;
1713 }
1714
1715 #endif  /* _NET_XFRM_H */