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         } props;
 166
 167         struct xfrm_lifetime_cfg lft;
 168
 169         /* Data for transformer */
 170         struct xfrm_algo_auth   *aalg;
 171         struct xfrm_algo        *ealg;
 172         struct xfrm_algo        *calg;
 173         struct xfrm_algo_aead   *aead;
 174
 175         /* Data for encapsulator */
 176         struct xfrm_encap_tmpl  *encap;
 177
 178         /* Data for care-of address */
 179         xfrm_address_t  *coaddr;
 180
 181         /* IPComp needs an IPIP tunnel for handling uncompressed packets */
 182         struct xfrm_state       *tunnel;
 183
 184         /* If a tunnel, number of users + 1 */
 185         atomic_t                tunnel_users;
 186
 187         /* State for replay detection */
 188         struct xfrm_replay_state replay;
 189         struct xfrm_replay_state_esn *replay_esn;
 190
 191         /* Replay detection state at the time we sent the last notification */
 192         struct xfrm_replay_state preplay;
 193         struct xfrm_replay_state_esn *preplay_esn;
 194
 195         /* The functions for replay detection. */
 196         struct xfrm_replay      *repl;
 197
 198         /* internal flag that only holds state for delayed aevent at the
 199          * moment
 200         */
 201         u32                     xflags;
 202
 203         /* Replay detection notification settings */
 204         u32                     replay_maxage;
 205         u32                     replay_maxdiff;
 206
 207         /* Replay detection notification timer */
 208         struct timer_list       rtimer;
 209
 210         /* Statistics */
 211         struct xfrm_stats       stats;
 212
 213         struct xfrm_lifetime_cur curlft;
 214         struct tasklet_hrtimer  mtimer;
 215
 216         /* Last used time */
 217         unsigned long           lastused;
 218
 219         /* Reference to data common to all the instances of this
 220          * transformer. */
 221         const struct xfrm_type  *type;
 222         struct xfrm_mode        *inner_mode;
 223         struct xfrm_mode        *inner_mode_iaf;
 224         struct xfrm_mode        *outer_mode;
 225
 226         /* Security context */
 227         struct xfrm_sec_ctx     *security;
 228
 229         /* Private data of this transformer, format is opaque,
 230          * interpreted by xfrm_type methods. */
 231         void                    *data;
 232 };
 233
 234 static inline struct net *xs_net(struct xfrm_state *x)
 235 {
 236         return read_pnet(&x->xs_net);
 237 }
 238
 239 /* xflags - make enum if more show up */
 240 #define XFRM_TIME_DEFER 1
 241
 242 enum {
 243         XFRM_STATE_VOID,
 244         XFRM_STATE_ACQ,
 245         XFRM_STATE_VALID,
 246         XFRM_STATE_ERROR,
 247         XFRM_STATE_EXPIRED,
 248         XFRM_STATE_DEAD
 249 };
 250
 251 /* callback structure passed from either netlink or pfkey */
 252 struct km_event {
 253         union {
 254                 u32 hard;
 255                 u32 proto;
 256                 u32 byid;
 257                 u32 aevent;
 258                 u32 type;
 259         } data;
 260
 261         u32     seq;
 262         u32     pid;
 263         u32     event;
 264         struct net *net;
 265 };
 266
 267 struct xfrm_replay {
 268         void    (*advance)(struct xfrm_state *x, __be32 net_seq);
 269         int     (*check)(struct xfrm_state *x,
 270                          struct sk_buff *skb,
 271                          __be32 net_seq);
 272         void    (*notify)(struct xfrm_state *x, int event);
 273         int     (*overflow)(struct xfrm_state *x, struct sk_buff *skb);
 274 };
 275
 276 struct net_device;
 277 struct xfrm_type;
 278 struct xfrm_dst;
 279 struct xfrm_policy_afinfo {
 280         unsigned short          family;
 281         struct dst_ops          *dst_ops;
 282         void                    (*garbage_collect)(struct net *net);
 283         struct dst_entry        *(*dst_lookup)(struct net *net, int tos,
 284                                                const xfrm_address_t *saddr,
 285                                                const xfrm_address_t *daddr);
 286         int                     (*get_saddr)(struct net *net, xfrm_address_t *saddr, xfrm_address_t *daddr);
 287         void                    (*decode_session)(struct sk_buff *skb,
 288                                                   struct flowi *fl,
 289                                                   int reverse);
 290         int                     (*get_tos)(const struct flowi *fl);
 291         int                     (*init_path)(struct xfrm_dst *path,
 292                                              struct dst_entry *dst,
 293                                              int nfheader_len);
 294         int                     (*fill_dst)(struct xfrm_dst *xdst,
 295                                             struct net_device *dev,
 296                                             const struct flowi *fl);
 297         struct dst_entry        *(*blackhole_route)(struct net *net, struct dst_entry *orig);
 298 };
 299
 300 extern int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo);
 301 extern int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo);
 302 extern void km_policy_notify(struct xfrm_policy *xp, int dir, const struct km_event *c);
 303 extern void km_state_notify(struct xfrm_state *x, const struct km_event *c);
 304
 305 struct xfrm_tmpl;
 306 extern int km_query(struct xfrm_state *x, struct xfrm_tmpl *t, struct xfrm_policy *pol);
 307 extern void km_state_expired(struct xfrm_state *x, int hard, u32 pid);
 308 extern int __xfrm_state_delete(struct xfrm_state *x);
 309
 310 struct xfrm_state_afinfo {
 311         unsigned int            family;
 312         unsigned int            proto;
 313         __be16                  eth_proto;
 314         struct module           *owner;
 315         const struct xfrm_type  *type_map[IPPROTO_MAX];
 316         struct xfrm_mode        *mode_map[XFRM_MODE_MAX];
 317         int                     (*init_flags)(struct xfrm_state *x);
 318         void                    (*init_tempsel)(struct xfrm_selector *sel,
 319                                                 const struct flowi *fl);
 320         void                    (*init_temprop)(struct xfrm_state *x,
 321                                                 const struct xfrm_tmpl *tmpl,
 322                                                 const xfrm_address_t *daddr,
 323                                                 const xfrm_address_t *saddr);
 324         int                     (*tmpl_sort)(struct xfrm_tmpl **dst, struct xfrm_tmpl **src, int n);
 325         int                     (*state_sort)(struct xfrm_state **dst, struct xfrm_state **src, int n);
 326         int                     (*output)(struct sk_buff *skb);
 327         int                     (*output_finish)(struct sk_buff *skb);
 328         int                     (*extract_input)(struct xfrm_state *x,
 329                                                  struct sk_buff *skb);
 330         int                     (*extract_output)(struct xfrm_state *x,
 331                                                   struct sk_buff *skb);
 332         int                     (*transport_finish)(struct sk_buff *skb,
 333                                                     int async);
 334 };
 335
 336 extern int xfrm_state_register_afinfo(struct xfrm_state_afinfo *afinfo);
 337 extern int xfrm_state_unregister_afinfo(struct xfrm_state_afinfo *afinfo);
 338
 339 extern void xfrm_state_delete_tunnel(struct xfrm_state *x);
 340
 341 struct xfrm_type {
 342         char                    *description;
 343         struct module           *owner;
 344         u8                      proto;
 345         u8                      flags;
 346 #define XFRM_TYPE_NON_FRAGMENT  1
 347 #define XFRM_TYPE_REPLAY_PROT   2
 348 #define XFRM_TYPE_LOCAL_COADDR  4
 349 #define XFRM_TYPE_REMOTE_COADDR 8
 350
 351         int                     (*init_state)(struct xfrm_state *x);
 352         void                    (*destructor)(struct xfrm_state *);
 353         int                     (*input)(struct xfrm_state *, struct sk_buff *skb);
 354         int                     (*output)(struct xfrm_state *, struct sk_buff *pskb);
 355         int                     (*reject)(struct xfrm_state *, struct sk_buff *,
 356                                           const struct flowi *);
 357         int                     (*hdr_offset)(struct xfrm_state *, struct sk_buff *, u8 **);
 358         /* Estimate maximal size of result of transformation of a dgram */
 359         u32                     (*get_mtu)(struct xfrm_state *, int size);
 360 };
 361
 362 extern int xfrm_register_type(const struct xfrm_type *type, unsigned short family);
 363 extern int xfrm_unregister_type(const struct xfrm_type *type, unsigned short family);
 364
 365 struct xfrm_mode {
 366         /*
 367          * Remove encapsulation header.
 368          *
 369          * The IP header will be moved over the top of the encapsulation
 370          * header.
 371          *
 372          * On entry, the transport header shall point to where the IP header
 373          * should be and the network header shall be set to where the IP
 374          * header currently is.  skb->data shall point to the start of the
 375          * payload.
 376          */
 377         int (*input2)(struct xfrm_state *x, struct sk_buff *skb);
 378
 379         /*
 380          * This is the actual input entry point.
 381          *
 382          * For transport mode and equivalent this would be identical to
 383          * input2 (which does not need to be set).  While tunnel mode
 384          * and equivalent would set this to the tunnel encapsulation function
 385          * xfrm4_prepare_input that would in turn call input2.
 386          */
 387         int (*input)(struct xfrm_state *x, struct sk_buff *skb);
 388
 389         /*
 390          * Add encapsulation header.
 391          *
 392          * On exit, the transport header will be set to the start of the
 393          * encapsulation header to be filled in by x->type->output and
 394          * the mac header will be set to the nextheader (protocol for
 395          * IPv4) field of the extension header directly preceding the
 396          * encapsulation header, or in its absence, that of the top IP
 397          * header.  The value of the network header will always point
 398          * to the top IP header while skb->data will point to the payload.
 399          */
 400         int (*output2)(struct xfrm_state *x,struct sk_buff *skb);
 401
 402         /*
 403          * This is the actual output entry point.
 404          *
 405          * For transport mode and equivalent this would be identical to
 406          * output2 (which does not need to be set).  While tunnel mode
 407          * and equivalent would set this to a tunnel encapsulation function
 408          * (xfrm4_prepare_output or xfrm6_prepare_output) that would in turn
 409          * call output2.
 410          */
 411         int (*output)(struct xfrm_state *x, struct sk_buff *skb);
 412
 413         struct xfrm_state_afinfo *afinfo;
 414         struct module *owner;
 415         unsigned int encap;
 416         int flags;
 417 };
 418
 419 /* Flags for xfrm_mode. */
 420 enum {
 421         XFRM_MODE_FLAG_TUNNEL = 1,
 422 };
 423
 424 extern int xfrm_register_mode(struct xfrm_mode *mode, int family);
 425 extern int xfrm_unregister_mode(struct xfrm_mode *mode, int family);
 426
 427 static inline int xfrm_af2proto(unsigned int family)
 428 {
 429         switch(family) {
 430         case AF_INET:
 431                 return IPPROTO_IPIP;
 432         case AF_INET6:
 433                 return IPPROTO_IPV6;
 434         default:
 435                 return 0;
 436         }
 437 }
 438
 439 static inline struct xfrm_mode *xfrm_ip2inner_mode(struct xfrm_state *x, int ipproto)
 440 {
 441         if ((ipproto == IPPROTO_IPIP && x->props.family == AF_INET) ||
 442             (ipproto == IPPROTO_IPV6 && x->props.family == AF_INET6))
 443                 return x->inner_mode;
 444         else
 445                 return x->inner_mode_iaf;
 446 }
 447
 448 struct xfrm_tmpl {
 449 /* id in template is interpreted as:
 450  * daddr - destination of tunnel, may be zero for transport mode.
 451  * spi   - zero to acquire spi. Not zero if spi is static, then
 452  *         daddr must be fixed too.
 453  * proto - AH/ESP/IPCOMP
 454  */
 455         struct xfrm_id          id;
 456
 457 /* Source address of tunnel. Ignored, if it is not a tunnel. */
 458         xfrm_address_t          saddr;
 459
 460         unsigned short          encap_family;
 461
 462         u32                     reqid;
 463
 464 /* Mode: transport, tunnel etc. */
 465         u8                      mode;
 466
 467 /* Sharing mode: unique, this session only, this user only etc. */
 468         u8                      share;
 469
 470 /* May skip this transfomration if no SA is found */
 471         u8                      optional;
 472
 473 /* Skip aalgos/ealgos/calgos checks. */
 474         u8                      allalgs;
 475
 476 /* Bit mask of algos allowed for acquisition */
 477         u32                     aalgos;
 478         u32                     ealgos;
 479         u32                     calgos;
 480 };
 481
 482 #define XFRM_MAX_DEPTH          6
 483
 484 struct xfrm_policy_walk_entry {
 485         struct list_head        all;
 486         u8                      dead;
 487 };
 488
 489 struct xfrm_policy_walk {
 490         struct xfrm_policy_walk_entry walk;
 491         u8 type;
 492         u32 seq;
 493 };
 494
 495 struct xfrm_policy {
 496 #ifdef CONFIG_NET_NS
 497         struct net              *xp_net;
 498 #endif
 499         struct hlist_node       bydst;
 500         struct hlist_node       byidx;
 501
 502         /* This lock only affects elements except for entry. */
 503         rwlock_t                lock;
 504         atomic_t                refcnt;
 505         struct timer_list       timer;
 506
 507         struct flow_cache_object flo;
 508         atomic_t                genid;
 509         u32                     priority;
 510         u32                     index;
 511         struct xfrm_mark        mark;
 512         struct xfrm_selector    selector;
 513         struct xfrm_lifetime_cfg lft;
 514         struct xfrm_lifetime_cur curlft;
 515         struct xfrm_policy_walk_entry walk;
 516         u8                      type;
 517         u8                      action;
 518         u8                      flags;
 519         u8                      xfrm_nr;
 520         u16                     family;
 521         struct xfrm_sec_ctx     *security;
 522         struct xfrm_tmpl        xfrm_vec[XFRM_MAX_DEPTH];
 523 };
 524
 525 static inline struct net *xp_net(const struct xfrm_policy *xp)
 526 {
 527         return read_pnet(&xp->xp_net);
 528 }
 529
 530 struct xfrm_kmaddress {
 531         xfrm_address_t          local;
 532         xfrm_address_t          remote;
 533         u32                     reserved;
 534         u16                     family;
 535 };
 536
 537 struct xfrm_migrate {
 538         xfrm_address_t          old_daddr;
 539         xfrm_address_t          old_saddr;
 540         xfrm_address_t          new_daddr;
 541         xfrm_address_t          new_saddr;
 542         u8                      proto;
 543         u8                      mode;
 544         u16                     reserved;
 545         u32                     reqid;
 546         u16                     old_family;
 547         u16                     new_family;
 548 };
 549
 550 #define XFRM_KM_TIMEOUT                30
 551 /* which seqno */
 552 #define XFRM_REPLAY_SEQ         1
 553 #define XFRM_REPLAY_OSEQ        2
 554 #define XFRM_REPLAY_SEQ_MASK    3
 555 /* what happened */
 556 #define XFRM_REPLAY_UPDATE      XFRM_AE_CR
 557 #define XFRM_REPLAY_TIMEOUT     XFRM_AE_CE
 558
 559 /* default aevent timeout in units of 100ms */
 560 #define XFRM_AE_ETIME                   10
 561 /* Async Event timer multiplier */
 562 #define XFRM_AE_ETH_M                   10
 563 /* default seq threshold size */
 564 #define XFRM_AE_SEQT_SIZE               2
 565
 566 struct xfrm_mgr {
 567         struct list_head        list;
 568         char                    *id;
 569         int                     (*notify)(struct xfrm_state *x, const struct km_event *c);
 570         int                     (*acquire)(struct xfrm_state *x, struct xfrm_tmpl *, struct xfrm_policy *xp, int dir);
 571         struct xfrm_policy      *(*compile_policy)(struct sock *sk, int opt, u8 *data, int len, int *dir);
 572         int                     (*new_mapping)(struct xfrm_state *x, xfrm_address_t *ipaddr, __be16 sport);
 573         int                     (*notify_policy)(struct xfrm_policy *x, int dir, const struct km_event *c);
 574         int                     (*report)(struct net *net, u8 proto, struct xfrm_selector *sel, xfrm_address_t *addr);
 575         int                     (*migrate)(const struct xfrm_selector *sel,
 576                                            u8 dir, u8 type,
 577                                            const struct xfrm_migrate *m,
 578                                            int num_bundles,
 579                                            const struct xfrm_kmaddress *k);
 580 };
 581
 582 extern int xfrm_register_km(struct xfrm_mgr *km);
 583 extern int xfrm_unregister_km(struct xfrm_mgr *km);
 584
 585 /*
 586  * This structure is used for the duration where packets are being
 587  * transformed by IPsec.  As soon as the packet leaves IPsec the
 588  * area beyond the generic IP part may be overwritten.
 589  */
 590 struct xfrm_skb_cb {
 591         union {
 592                 struct inet_skb_parm h4;
 593                 struct inet6_skb_parm h6;
 594         } header;
 595
 596         /* Sequence number for replay protection. */
 597         union {
 598                 struct {
 599                         __u32 low;
 600                         __u32 hi;
 601                 } output;
 602                 struct {
 603                         __be32 low;
 604                         __be32 hi;
 605                 } input;
 606         } seq;
 607 };
 608
 609 #define XFRM_SKB_CB(__skb) ((struct xfrm_skb_cb *)&((__skb)->cb[0]))
 610
 611 /*
 612  * This structure is used by the afinfo prepare_input/prepare_output functions
 613  * to transmit header information to the mode input/output functions.
 614  */
 615 struct xfrm_mode_skb_cb {
 616         union {
 617                 struct inet_skb_parm h4;
 618                 struct inet6_skb_parm h6;
 619         } header;
 620
 621         /* Copied from header for IPv4, always set to zero and DF for IPv6. */
 622         __be16 id;
 623         __be16 frag_off;
 624
 625         /* IP header length (excluding options or extension headers). */
 626         u8 ihl;
 627
 628         /* TOS for IPv4, class for IPv6. */
 629         u8 tos;
 630
 631         /* TTL for IPv4, hop limitfor IPv6. */
 632         u8 ttl;
 633
 634         /* Protocol for IPv4, NH for IPv6. */
 635         u8 protocol;
 636
 637         /* Option length for IPv4, zero for IPv6. */
 638         u8 optlen;
 639
 640         /* Used by IPv6 only, zero for IPv4. */
 641         u8 flow_lbl[3];
 642 };
 643
 644 #define XFRM_MODE_SKB_CB(__skb) ((struct xfrm_mode_skb_cb *)&((__skb)->cb[0]))
 645
 646 /*
 647  * This structure is used by the input processing to locate the SPI and
 648  * related information.
 649  */
 650 struct xfrm_spi_skb_cb {
 651         union {
 652                 struct inet_skb_parm h4;
 653                 struct inet6_skb_parm h6;
 654         } header;
 655
 656         unsigned int daddroff;
 657         unsigned int family;
 658 };
 659
 660 #define XFRM_SPI_SKB_CB(__skb) ((struct xfrm_spi_skb_cb *)&((__skb)->cb[0]))
 661
 662 /* Audit Information */
 663 struct xfrm_audit {
 664         u32     secid;
 665         uid_t   loginuid;
 666         u32     sessionid;
 667 };
 668
 669 #ifdef CONFIG_AUDITSYSCALL
 670 static inline struct audit_buffer *xfrm_audit_start(const char *op)
 671 {
 672         struct audit_buffer *audit_buf = NULL;
 673
 674         if (audit_enabled == 0)
 675                 return NULL;
 676         audit_buf = audit_log_start(current->audit_context, GFP_ATOMIC,
 677                                     AUDIT_MAC_IPSEC_EVENT);
 678         if (audit_buf == NULL)
 679                 return NULL;
 680         audit_log_format(audit_buf, "op=%s", op);
 681         return audit_buf;
 682 }
 683
 684 static inline void xfrm_audit_helper_usrinfo(uid_t auid, u32 ses, u32 secid,
 685                                              struct audit_buffer *audit_buf)
 686 {
 687         char *secctx;
 688         u32 secctx_len;
 689
 690         audit_log_format(audit_buf, " auid=%u ses=%u", auid, ses);
 691         if (secid != 0 &&
 692             security_secid_to_secctx(secid, &secctx, &secctx_len) == 0) {
 693                 audit_log_format(audit_buf, " subj=%s", secctx);
 694                 security_release_secctx(secctx, secctx_len);
 695         } else
 696                 audit_log_task_context(audit_buf);
 697 }
 698
 699 extern void xfrm_audit_policy_add(struct xfrm_policy *xp, int result,
 700                                   u32 auid, u32 ses, u32 secid);
 701 extern void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
 702                                   u32 auid, u32 ses, u32 secid);
 703 extern void xfrm_audit_state_add(struct xfrm_state *x, int result,
 704                                  u32 auid, u32 ses, u32 secid);
 705 extern void xfrm_audit_state_delete(struct xfrm_state *x, int result,
 706                                     u32 auid, u32 ses, u32 secid);
 707 extern void xfrm_audit_state_replay_overflow(struct xfrm_state *x,
 708                                              struct sk_buff *skb);
 709 extern void xfrm_audit_state_replay(struct xfrm_state *x,
 710                                     struct sk_buff *skb, __be32 net_seq);
 711 extern void xfrm_audit_state_notfound_simple(struct sk_buff *skb, u16 family);
 712 extern void xfrm_audit_state_notfound(struct sk_buff *skb, u16 family,
 713                                       __be32 net_spi, __be32 net_seq);
 714 extern void xfrm_audit_state_icvfail(struct xfrm_state *x,
 715                                      struct sk_buff *skb, u8 proto);
 716 #else
 717
 718 static inline void xfrm_audit_policy_add(struct xfrm_policy *xp, int result,
 719                                   u32 auid, u32 ses, u32 secid)
 720 {
 721 }
 722
 723 static inline void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
 724                                   u32 auid, u32 ses, u32 secid)
 725 {
 726 }
 727
 728 static inline void xfrm_audit_state_add(struct xfrm_state *x, int result,
 729                                  u32 auid, u32 ses, u32 secid)
 730 {
 731 }
 732
 733 static inline void xfrm_audit_state_delete(struct xfrm_state *x, int result,
 734                                     u32 auid, u32 ses, u32 secid)
 735 {
 736 }
 737
 738 static inline void xfrm_audit_state_replay_overflow(struct xfrm_state *x,
 739                                              struct sk_buff *skb)
 740 {
 741 }
 742
 743 static inline void xfrm_audit_state_replay(struct xfrm_state *x,
 744                                            struct sk_buff *skb, __be32 net_seq)
 745 {
 746 }
 747
 748 static inline void xfrm_audit_state_notfound_simple(struct sk_buff *skb,
 749                                       u16 family)
 750 {
 751 }
 752
 753 static inline void xfrm_audit_state_notfound(struct sk_buff *skb, u16 family,
 754                                       __be32 net_spi, __be32 net_seq)
 755 {
 756 }
 757
 758 static inline void xfrm_audit_state_icvfail(struct xfrm_state *x,
 759                                      struct sk_buff *skb, u8 proto)
 760 {
 761 }
 762 #endif /* CONFIG_AUDITSYSCALL */
 763
 764 static inline void xfrm_pol_hold(struct xfrm_policy *policy)
 765 {
 766         if (likely(policy != NULL))
 767                 atomic_inc(&policy->refcnt);
 768 }
 769
 770 extern void xfrm_policy_destroy(struct xfrm_policy *policy);
 771
 772 static inline void xfrm_pol_put(struct xfrm_policy *policy)
 773 {
 774         if (atomic_dec_and_test(&policy->refcnt))
 775                 xfrm_policy_destroy(policy);
 776 }
 777
 778 static inline void xfrm_pols_put(struct xfrm_policy **pols, int npols)
 779 {
 780         int i;
 781         for (i = npols - 1; i >= 0; --i)
 782                 xfrm_pol_put(pols[i]);
 783 }
 784
 785 extern void __xfrm_state_destroy(struct xfrm_state *);
 786
 787 static inline void __xfrm_state_put(struct xfrm_state *x)
 788 {
 789         atomic_dec(&x->refcnt);
 790 }
 791
 792 static inline void xfrm_state_put(struct xfrm_state *x)
 793 {
 794         if (atomic_dec_and_test(&x->refcnt))
 795                 __xfrm_state_destroy(x);
 796 }
 797
 798 static inline void xfrm_state_hold(struct xfrm_state *x)
 799 {
 800         atomic_inc(&x->refcnt);
 801 }
 802
 803 static inline bool addr_match(const void *token1, const void *token2,
 804                               int prefixlen)
 805 {
 806         const __be32 *a1 = token1;
 807         const __be32 *a2 = token2;
 808         int pdw;
 809         int pbi;
 810
 811         pdw = prefixlen >> 5;     /* num of whole u32 in prefix */
 812         pbi = prefixlen &  0x1f;  /* num of bits in incomplete u32 in prefix */
 813
 814         if (pdw)
 815                 if (memcmp(a1, a2, pdw << 2))
 816                         return false;
 817
 818         if (pbi) {
 819                 __be32 mask;
 820
 821                 mask = htonl((0xffffffff) << (32 - pbi));
 822
 823                 if ((a1[pdw] ^ a2[pdw]) & mask)
 824                         return false;
 825         }
 826
 827         return true;
 828 }
 829
 830 static __inline__
 831 __be16 xfrm_flowi_sport(const struct flowi *fl, const union flowi_uli *uli)
 832 {
 833         __be16 port;
 834         switch(fl->flowi_proto) {
 835         case IPPROTO_TCP:
 836         case IPPROTO_UDP:
 837         case IPPROTO_UDPLITE:
 838         case IPPROTO_SCTP:
 839                 port = uli->ports.sport;
 840                 break;
 841         case IPPROTO_ICMP:
 842         case IPPROTO_ICMPV6:
 843                 port = htons(uli->icmpt.type);
 844                 break;
 845         case IPPROTO_MH:
 846                 port = htons(uli->mht.type);
 847                 break;
 848         case IPPROTO_GRE:
 849                 port = htons(ntohl(uli->gre_key) >> 16);
 850                 break;
 851         default:
 852                 port = 0;       /*XXX*/
 853         }
 854         return port;
 855 }
 856
 857 static __inline__
 858 __be16 xfrm_flowi_dport(const struct flowi *fl, const union flowi_uli *uli)
 859 {
 860         __be16 port;
 861         switch(fl->flowi_proto) {
 862         case IPPROTO_TCP:
 863         case IPPROTO_UDP:
 864         case IPPROTO_UDPLITE:
 865         case IPPROTO_SCTP:
 866                 port = uli->ports.dport;
 867                 break;
 868         case IPPROTO_ICMP:
 869         case IPPROTO_ICMPV6:
 870                 port = htons(uli->icmpt.code);
 871                 break;
 872         case IPPROTO_GRE:
 873                 port = htons(ntohl(uli->gre_key) & 0xffff);
 874                 break;
 875         default:
 876                 port = 0;       /*XXX*/
 877         }
 878         return port;
 879 }
 880
 881 extern int xfrm_selector_match(const struct xfrm_selector *sel,
 882                                const struct flowi *fl,
 883                                unsigned short family);
 884
 885 #ifdef CONFIG_SECURITY_NETWORK_XFRM
 886 /*      If neither has a context --> match
 887  *      Otherwise, both must have a context and the sids, doi, alg must match
 888  */
 889 static inline int xfrm_sec_ctx_match(struct xfrm_sec_ctx *s1, struct xfrm_sec_ctx *s2)
 890 {
 891         return ((!s1 && !s2) ||
 892                 (s1 && s2 &&
 893                  (s1->ctx_sid == s2->ctx_sid) &&
 894                  (s1->ctx_doi == s2->ctx_doi) &&
 895                  (s1->ctx_alg == s2->ctx_alg)));
 896 }
 897 #else
 898 static inline int xfrm_sec_ctx_match(struct xfrm_sec_ctx *s1, struct xfrm_sec_ctx *s2)
 899 {
 900         return 1;
 901 }
 902 #endif
 903
 904 /* A struct encoding bundle of transformations to apply to some set of flow.
 905  *
 906  * dst->child points to the next element of bundle.
 907  * dst->xfrm  points to an instanse of transformer.
 908  *
 909  * Due to unfortunate limitations of current routing cache, which we
 910  * have no time to fix, it mirrors struct rtable and bound to the same
 911  * routing key, including saddr,daddr. However, we can have many of
 912  * bundles differing by session id. All the bundles grow from a parent
 913  * policy rule.
 914  */
 915 struct xfrm_dst {
 916         union {
 917                 struct dst_entry        dst;
 918                 struct rtable           rt;
 919                 struct rt6_info         rt6;
 920         } u;
 921         struct dst_entry *route;
 922         struct flow_cache_object flo;
 923         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
 924         int num_pols, num_xfrms;
 925 #ifdef CONFIG_XFRM_SUB_POLICY
 926         struct flowi *origin;
 927         struct xfrm_selector *partner;
 928 #endif
 929         u32 xfrm_genid;
 930         u32 policy_genid;
 931         u32 route_mtu_cached;
 932         u32 child_mtu_cached;
 933         u32 route_cookie;
 934         u32 path_cookie;
 935 };
 936
 937 #ifdef CONFIG_XFRM
 938 static inline void xfrm_dst_destroy(struct xfrm_dst *xdst)
 939 {
 940         xfrm_pols_put(xdst->pols, xdst->num_pols);
 941         dst_release(xdst->route);
 942         if (likely(xdst->u.dst.xfrm))
 943                 xfrm_state_put(xdst->u.dst.xfrm);
 944 #ifdef CONFIG_XFRM_SUB_POLICY
 945         kfree(xdst->origin);
 946         xdst->origin = NULL;
 947         kfree(xdst->partner);
 948         xdst->partner = NULL;
 949 #endif
 950 }
 951 #endif
 952
 953 extern void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev);
 954
 955 struct sec_path {
 956         atomic_t                refcnt;
 957         int                     len;
 958         struct xfrm_state       *xvec[XFRM_MAX_DEPTH];
 959 };
 960
 961 static inline struct sec_path *
 962 secpath_get(struct sec_path *sp)
 963 {
 964         if (sp)
 965                 atomic_inc(&sp->refcnt);
 966         return sp;
 967 }
 968
 969 extern void __secpath_destroy(struct sec_path *sp);
 970
 971 static inline void
 972 secpath_put(struct sec_path *sp)
 973 {
 974         if (sp && atomic_dec_and_test(&sp->refcnt))
 975                 __secpath_destroy(sp);
 976 }
 977
 978 extern struct sec_path *secpath_dup(struct sec_path *src);
 979
 980 static inline void
 981 secpath_reset(struct sk_buff *skb)
 982 {
 983 #ifdef CONFIG_XFRM
 984         secpath_put(skb->sp);
 985         skb->sp = NULL;
 986 #endif
 987 }
 988
 989 static inline int
 990 xfrm_addr_any(const xfrm_address_t *addr, unsigned short family)
 991 {
 992         switch (family) {
 993         case AF_INET:
 994                 return addr->a4 == 0;
 995         case AF_INET6:
 996                 return ipv6_addr_any((struct in6_addr *)&addr->a6);
 997         }
 998         return 0;
 999 }
1000
1001 static inline int
1002 __xfrm4_state_addr_cmp(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x)
1003 {
1004         return  (tmpl->saddr.a4 &&
1005                  tmpl->saddr.a4 != x->props.saddr.a4);
1006 }
1007
1008 static inline int
1009 __xfrm6_state_addr_cmp(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x)
1010 {
1011         return  (!ipv6_addr_any((struct in6_addr*)&tmpl->saddr) &&
1012                  ipv6_addr_cmp((struct in6_addr *)&tmpl->saddr, (struct in6_addr*)&x->props.saddr));
1013 }
1014
1015 static inline int
1016 xfrm_state_addr_cmp(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, unsigned short family)
1017 {
1018         switch (family) {
1019         case AF_INET:
1020                 return __xfrm4_state_addr_cmp(tmpl, x);
1021         case AF_INET6:
1022                 return __xfrm6_state_addr_cmp(tmpl, x);
1023         }
1024         return !0;
1025 }
1026
1027 #ifdef CONFIG_XFRM
1028 extern int __xfrm_policy_check(struct sock *, int dir, struct sk_buff *skb, unsigned short family);
1029
1030 static inline int __xfrm_policy_check2(struct sock *sk, int dir,
1031                                        struct sk_buff *skb,
1032                                        unsigned int family, int reverse)
1033 {
1034         struct net *net = dev_net(skb->dev);
1035         int ndir = dir | (reverse ? XFRM_POLICY_MASK + 1 : 0);
1036
1037         if (sk && sk->sk_policy[XFRM_POLICY_IN])
1038                 return __xfrm_policy_check(sk, ndir, skb, family);
1039
1040         return  (!net->xfrm.policy_count[dir] && !skb->sp) ||
1041                 (skb_dst(skb)->flags & DST_NOPOLICY) ||
1042                 __xfrm_policy_check(sk, ndir, skb, family);
1043 }
1044
1045 static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
1046 {
1047         return __xfrm_policy_check2(sk, dir, skb, family, 0);
1048 }
1049
1050 static inline int xfrm4_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
1051 {
1052         return xfrm_policy_check(sk, dir, skb, AF_INET);
1053 }
1054
1055 static inline int xfrm6_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
1056 {
1057         return xfrm_policy_check(sk, dir, skb, AF_INET6);
1058 }
1059
1060 static inline int xfrm4_policy_check_reverse(struct sock *sk, int dir,
1061                                              struct sk_buff *skb)
1062 {
1063         return __xfrm_policy_check2(sk, dir, skb, AF_INET, 1);
1064 }
1065
1066 static inline int xfrm6_policy_check_reverse(struct sock *sk, int dir,
1067                                              struct sk_buff *skb)
1068 {
1069         return __xfrm_policy_check2(sk, dir, skb, AF_INET6, 1);
1070 }
1071
1072 extern int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
1073                                  unsigned int family, int reverse);
1074
1075 static inline int xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
1076                                       unsigned int family)
1077 {
1078         return __xfrm_decode_session(skb, fl, family, 0);
1079 }
1080
1081 static inline int xfrm_decode_session_reverse(struct sk_buff *skb,
1082                                               struct flowi *fl,
1083                                               unsigned int family)
1084 {
1085         return __xfrm_decode_session(skb, fl, family, 1);
1086 }
1087
1088 extern int __xfrm_route_forward(struct sk_buff *skb, unsigned short family);
1089
1090 static inline int xfrm_route_forward(struct sk_buff *skb, unsigned short family)
1091 {
1092         struct net *net = dev_net(skb->dev);
1093
1094         return  !net->xfrm.policy_count[XFRM_POLICY_OUT] ||
1095                 (skb_dst(skb)->flags & DST_NOXFRM) ||
1096                 __xfrm_route_forward(skb, family);
1097 }
1098
1099 static inline int xfrm4_route_forward(struct sk_buff *skb)
1100 {
1101         return xfrm_route_forward(skb, AF_INET);
1102 }
1103
1104 static inline int xfrm6_route_forward(struct sk_buff *skb)
1105 {
1106         return xfrm_route_forward(skb, AF_INET6);
1107 }
1108
1109 extern int __xfrm_sk_clone_policy(struct sock *sk);
1110
1111 static inline int xfrm_sk_clone_policy(struct sock *sk)
1112 {
1113         if (unlikely(sk->sk_policy[0] || sk->sk_policy[1]))
1114                 return __xfrm_sk_clone_policy(sk);
1115         return 0;
1116 }
1117
1118 extern int xfrm_policy_delete(struct xfrm_policy *pol, int dir);
1119
1120 static inline void xfrm_sk_free_policy(struct sock *sk)
1121 {
1122         if (unlikely(sk->sk_policy[0] != NULL)) {
1123                 xfrm_policy_delete(sk->sk_policy[0], XFRM_POLICY_MAX);
1124                 sk->sk_policy[0] = NULL;
1125         }
1126         if (unlikely(sk->sk_policy[1] != NULL)) {
1127                 xfrm_policy_delete(sk->sk_policy[1], XFRM_POLICY_MAX+1);
1128                 sk->sk_policy[1] = NULL;
1129         }
1130 }
1131
1132 #else
1133
1134 static inline void xfrm_sk_free_policy(struct sock *sk) {}
1135 static inline int xfrm_sk_clone_policy(struct sock *sk) { return 0; }
1136 static inline int xfrm6_route_forward(struct sk_buff *skb) { return 1; }
1137 static inline int xfrm4_route_forward(struct sk_buff *skb) { return 1; }
1138 static inline int xfrm6_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
1139 {
1140         return 1;
1141 }
1142 static inline int xfrm4_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
1143 {
1144         return 1;
1145 }
1146 static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
1147 {
1148         return 1;
1149 }
1150 static inline int xfrm_decode_session_reverse(struct sk_buff *skb,
1151                                               struct flowi *fl,
1152                                               unsigned int family)
1153 {
1154         return -ENOSYS;
1155 }
1156 static inline int xfrm4_policy_check_reverse(struct sock *sk, int dir,
1157                                              struct sk_buff *skb)
1158 {
1159         return 1;
1160 }
1161 static inline int xfrm6_policy_check_reverse(struct sock *sk, int dir,
1162                                              struct sk_buff *skb)
1163 {
1164         return 1;
1165 }
1166 #endif
1167
1168 static __inline__
1169 xfrm_address_t *xfrm_flowi_daddr(const struct flowi *fl, unsigned short family)
1170 {
1171         switch (family){
1172         case AF_INET:
1173                 return (xfrm_address_t *)&fl->u.ip4.daddr;
1174         case AF_INET6:
1175                 return (xfrm_address_t *)&fl->u.ip6.daddr;
1176         }
1177         return NULL;
1178 }
1179
1180 static __inline__
1181 xfrm_address_t *xfrm_flowi_saddr(const struct flowi *fl, unsigned short family)
1182 {
1183         switch (family){
1184         case AF_INET:
1185                 return (xfrm_address_t *)&fl->u.ip4.saddr;
1186         case AF_INET6:
1187                 return (xfrm_address_t *)&fl->u.ip6.saddr;
1188         }
1189         return NULL;
1190 }
1191
1192 static __inline__
1193 void xfrm_flowi_addr_get(const struct flowi *fl,
1194                          xfrm_address_t *saddr, xfrm_address_t *daddr,
1195                          unsigned short family)
1196 {
1197         switch(family) {
1198         case AF_INET:
1199                 memcpy(&saddr->a4, &fl->u.ip4.saddr, sizeof(saddr->a4));
1200                 memcpy(&daddr->a4, &fl->u.ip4.daddr, sizeof(daddr->a4));
1201                 break;
1202         case AF_INET6:
1203                 ipv6_addr_copy((struct in6_addr *)&saddr->a6, &fl->u.ip6.saddr);
1204                 ipv6_addr_copy((struct in6_addr *)&daddr->a6, &fl->u.ip6.daddr);
1205                 break;
1206         }
1207 }
1208
1209 static __inline__ int
1210 __xfrm4_state_addr_check(const struct xfrm_state *x,
1211                          const xfrm_address_t *daddr, const xfrm_address_t *saddr)
1212 {
1213         if (daddr->a4 == x->id.daddr.a4 &&
1214             (saddr->a4 == x->props.saddr.a4 || !saddr->a4 || !x->props.saddr.a4))
1215                 return 1;
1216         return 0;
1217 }
1218
1219 static __inline__ int
1220 __xfrm6_state_addr_check(const struct xfrm_state *x,
1221                          const xfrm_address_t *daddr, const xfrm_address_t *saddr)
1222 {
1223         if (!ipv6_addr_cmp((struct in6_addr *)daddr, (struct in6_addr *)&x->id.daddr) &&
1224             (!ipv6_addr_cmp((struct in6_addr *)saddr, (struct in6_addr *)&x->props.saddr)||
1225              ipv6_addr_any((struct in6_addr *)saddr) ||
1226              ipv6_addr_any((struct in6_addr *)&x->props.saddr)))
1227                 return 1;
1228         return 0;
1229 }
1230
1231 static __inline__ int
1232 xfrm_state_addr_check(const struct xfrm_state *x,
1233                       const xfrm_address_t *daddr, const xfrm_address_t *saddr,
1234                       unsigned short family)
1235 {
1236         switch (family) {
1237         case AF_INET:
1238                 return __xfrm4_state_addr_check(x, daddr, saddr);
1239         case AF_INET6:
1240                 return __xfrm6_state_addr_check(x, daddr, saddr);
1241         }
1242         return 0;
1243 }
1244
1245 static __inline__ int
1246 xfrm_state_addr_flow_check(const struct xfrm_state *x, const struct flowi *fl,
1247                            unsigned short family)
1248 {
1249         switch (family) {
1250         case AF_INET:
1251                 return __xfrm4_state_addr_check(x,
1252                                                 (const xfrm_address_t *)&fl->u.ip4.daddr,
1253                                                 (const xfrm_address_t *)&fl->u.ip4.saddr);
1254         case AF_INET6:
1255                 return __xfrm6_state_addr_check(x,
1256                                                 (const xfrm_address_t *)&fl->u.ip6.daddr,
1257                                                 (const xfrm_address_t *)&fl->u.ip6.saddr);
1258         }
1259         return 0;
1260 }
1261
1262 static inline int xfrm_state_kern(const struct xfrm_state *x)
1263 {
1264         return atomic_read(&x->tunnel_users);
1265 }
1266
1267 static inline int xfrm_id_proto_match(u8 proto, u8 userproto)
1268 {
1269         return (!userproto || proto == userproto ||
1270                 (userproto == IPSEC_PROTO_ANY && (proto == IPPROTO_AH ||
1271                                                   proto == IPPROTO_ESP ||
1272                                                   proto == IPPROTO_COMP)));
1273 }
1274
1275 /*
1276  * xfrm algorithm information
1277  */
1278 struct xfrm_algo_aead_info {
1279         u16 icv_truncbits;
1280 };
1281
1282 struct xfrm_algo_auth_info {
1283         u16 icv_truncbits;
1284         u16 icv_fullbits;
1285 };
1286
1287 struct xfrm_algo_encr_info {
1288         u16 blockbits;
1289         u16 defkeybits;
1290 };
1291
1292 struct xfrm_algo_comp_info {
1293         u16 threshold;
1294 };
1295
1296 struct xfrm_algo_desc {
1297         char *name;
1298         char *compat;
1299         u8 available:1;
1300         union {
1301                 struct xfrm_algo_aead_info aead;
1302                 struct xfrm_algo_auth_info auth;
1303                 struct xfrm_algo_encr_info encr;
1304                 struct xfrm_algo_comp_info comp;
1305         } uinfo;
1306         struct sadb_alg desc;
1307 };
1308
1309 /* XFRM tunnel handlers.  */
1310 struct xfrm_tunnel {
1311         int (*handler)(struct sk_buff *skb);
1312         int (*err_handler)(struct sk_buff *skb, u32 info);
1313
1314         struct xfrm_tunnel __rcu *next;
1315         int priority;
1316 };
1317
1318 struct xfrm6_tunnel {
1319         int (*handler)(struct sk_buff *skb);
1320         int (*err_handler)(struct sk_buff *skb, struct inet6_skb_parm *opt,
1321                            u8 type, u8 code, int offset, __be32 info);
1322         struct xfrm6_tunnel __rcu *next;
1323         int priority;
1324 };
1325
1326 extern void xfrm_init(void);
1327 extern void xfrm4_init(int rt_hash_size);
1328 extern int xfrm_state_init(struct net *net);
1329 extern void xfrm_state_fini(struct net *net);
1330 extern void xfrm4_state_init(void);
1331 #ifdef CONFIG_XFRM
1332 extern int xfrm6_init(void);
1333 extern void xfrm6_fini(void);
1334 extern int xfrm6_state_init(void);
1335 extern void xfrm6_state_fini(void);
1336 #else
1337 static inline int xfrm6_init(void)
1338 {
1339         return 0;
1340 }
1341 static inline void xfrm6_fini(void)
1342 {
1343         ;
1344 }
1345 #endif
1346
1347 #ifdef CONFIG_XFRM_STATISTICS
1348 extern int xfrm_proc_init(struct net *net);
1349 extern void xfrm_proc_fini(struct net *net);
1350 #endif
1351
1352 extern int xfrm_sysctl_init(struct net *net);
1353 #ifdef CONFIG_SYSCTL
1354 extern void xfrm_sysctl_fini(struct net *net);
1355 #else
1356 static inline void xfrm_sysctl_fini(struct net *net)
1357 {
1358 }
1359 #endif
1360
1361 extern void xfrm_state_walk_init(struct xfrm_state_walk *walk, u8 proto);
1362 extern int xfrm_state_walk(struct net *net, struct xfrm_state_walk *walk,
1363                            int (*func)(struct xfrm_state *, int, void*), void *);
1364 extern void xfrm_state_walk_done(struct xfrm_state_walk *walk);
1365 extern struct xfrm_state *xfrm_state_alloc(struct net *net);
1366 extern struct xfrm_state *xfrm_state_find(const xfrm_address_t *daddr,
1367                                           const xfrm_address_t *saddr,
1368                                           const struct flowi *fl,
1369                                           struct xfrm_tmpl *tmpl,
1370                                           struct xfrm_policy *pol, int *err,
1371                                           unsigned short family);
1372 extern struct xfrm_state *xfrm_stateonly_find(struct net *net, u32 mark,
1373                                                xfrm_address_t *daddr,
1374                                                xfrm_address_t *saddr,
1375                                                unsigned short family,
1376                                                u8 mode, u8 proto, u32 reqid);
1377 extern int xfrm_state_check_expire(struct xfrm_state *x);
1378 extern void xfrm_state_insert(struct xfrm_state *x);
1379 extern int xfrm_state_add(struct xfrm_state *x);
1380 extern int xfrm_state_update(struct xfrm_state *x);
1381 extern struct xfrm_state *xfrm_state_lookup(struct net *net, u32 mark,
1382                                             const xfrm_address_t *daddr, __be32 spi,
1383                                             u8 proto, unsigned short family);
1384 extern struct xfrm_state *xfrm_state_lookup_byaddr(struct net *net, u32 mark,
1385                                                    const xfrm_address_t *daddr,
1386                                                    const xfrm_address_t *saddr,
1387                                                    u8 proto,
1388                                                    unsigned short family);
1389 #ifdef CONFIG_XFRM_SUB_POLICY
1390 extern int xfrm_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src,
1391                           int n, unsigned short family);
1392 extern int xfrm_state_sort(struct xfrm_state **dst, struct xfrm_state **src,
1393                            int n, unsigned short family);
1394 #else
1395 static inline int xfrm_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src,
1396                                  int n, unsigned short family)
1397 {
1398         return -ENOSYS;
1399 }
1400
1401 static inline int xfrm_state_sort(struct xfrm_state **dst, struct xfrm_state **src,
1402                                   int n, unsigned short family)
1403 {
1404         return -ENOSYS;
1405 }
1406 #endif
1407
1408 struct xfrmk_sadinfo {
1409         u32 sadhcnt; /* current hash bkts */
1410         u32 sadhmcnt; /* max allowed hash bkts */
1411         u32 sadcnt; /* current running count */
1412 };
1413
1414 struct xfrmk_spdinfo {
1415         u32 incnt;
1416         u32 outcnt;
1417         u32 fwdcnt;
1418         u32 inscnt;
1419         u32 outscnt;
1420         u32 fwdscnt;
1421         u32 spdhcnt;
1422         u32 spdhmcnt;
1423 };
1424
1425 extern struct xfrm_state *xfrm_find_acq_byseq(struct net *net, u32 mark,
1426                                               u32 seq);
1427 extern int xfrm_state_delete(struct xfrm_state *x);
1428 extern int xfrm_state_flush(struct net *net, u8 proto, struct xfrm_audit *audit_info);
1429 extern void xfrm_sad_getinfo(struct net *net, struct xfrmk_sadinfo *si);
1430 extern void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si);
1431 extern u32 xfrm_replay_seqhi(struct xfrm_state *x, __be32 net_seq);
1432 extern int xfrm_init_replay(struct xfrm_state *x);
1433 extern int xfrm_state_mtu(struct xfrm_state *x, int mtu);
1434 extern int __xfrm_init_state(struct xfrm_state *x, bool init_replay);
1435 extern int xfrm_init_state(struct xfrm_state *x);
1436 extern int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb);
1437 extern int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi,
1438                       int encap_type);
1439 extern int xfrm_input_resume(struct sk_buff *skb, int nexthdr);
1440 extern int xfrm_output_resume(struct sk_buff *skb, int err);
1441 extern int xfrm_output(struct sk_buff *skb);
1442 extern int xfrm_inner_extract_output(struct xfrm_state *x, struct sk_buff *skb);
1443 extern int xfrm4_extract_header(struct sk_buff *skb);
1444 extern int xfrm4_extract_input(struct xfrm_state *x, struct sk_buff *skb);
1445 extern int xfrm4_rcv_encap(struct sk_buff *skb, int nexthdr, __be32 spi,
1446                            int encap_type);
1447 extern int xfrm4_transport_finish(struct sk_buff *skb, int async);
1448 extern int xfrm4_rcv(struct sk_buff *skb);
1449
1450 static inline int xfrm4_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi)
1451 {
1452         return xfrm4_rcv_encap(skb, nexthdr, spi, 0);
1453 }
1454
1455 extern int xfrm4_extract_output(struct xfrm_state *x, struct sk_buff *skb);
1456 extern int xfrm4_prepare_output(struct xfrm_state *x, struct sk_buff *skb);
1457 extern int xfrm4_output(struct sk_buff *skb);
1458 extern int xfrm4_output_finish(struct sk_buff *skb);
1459 extern int xfrm4_tunnel_register(struct xfrm_tunnel *handler, unsigned short family);
1460 extern int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler, unsigned short family);
1461 extern int xfrm6_extract_header(struct sk_buff *skb);
1462 extern int xfrm6_extract_input(struct xfrm_state *x, struct sk_buff *skb);
1463 extern int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi);
1464 extern int xfrm6_transport_finish(struct sk_buff *skb, int async);
1465 extern int xfrm6_rcv(struct sk_buff *skb);
1466 extern int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
1467                             xfrm_address_t *saddr, u8 proto);
1468 extern int xfrm6_tunnel_register(struct xfrm6_tunnel *handler, unsigned short family);
1469 extern int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler, unsigned short family);
1470 extern __be32 xfrm6_tunnel_alloc_spi(struct net *net, xfrm_address_t *saddr);
1471 extern __be32 xfrm6_tunnel_spi_lookup(struct net *net, xfrm_address_t *saddr);
1472 extern int xfrm6_extract_output(struct xfrm_state *x, struct sk_buff *skb);
1473 extern int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb);
1474 extern int xfrm6_output(struct sk_buff *skb);
1475 extern int xfrm6_output_finish(struct sk_buff *skb);
1476 extern int xfrm6_find_1stfragopt(struct xfrm_state *x, struct sk_buff *skb,
1477                                  u8 **prevhdr);
1478
1479 #ifdef CONFIG_XFRM
1480 extern int xfrm4_udp_encap_rcv(struct sock *sk, struct sk_buff *skb);
1481 extern int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen);
1482 #else
1483 static inline int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen)
1484 {
1485         return -ENOPROTOOPT;
1486 }
1487
1488 static inline int xfrm4_udp_encap_rcv(struct sock *sk, struct sk_buff *skb)
1489 {
1490         /* should not happen */
1491         kfree_skb(skb);
1492         return 0;
1493 }
1494 #endif
1495
1496 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp);
1497
1498 extern void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type);
1499 extern int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
1500         int (*func)(struct xfrm_policy *, int, int, void*), void *);
1501 extern void xfrm_policy_walk_done(struct xfrm_policy_walk *walk);
1502 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl);
1503 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark,
1504                                           u8 type, int dir,
1505                                           struct xfrm_selector *sel,
1506                                           struct xfrm_sec_ctx *ctx, int delete,
1507                                           int *err);
1508 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8, int dir, u32 id, int delete, int *err);
1509 int xfrm_policy_flush(struct net *net, u8 type, struct xfrm_audit *audit_info);
1510 u32 xfrm_get_acqseq(void);
1511 extern int xfrm_alloc_spi(struct xfrm_state *x, u32 minspi, u32 maxspi);
1512 struct xfrm_state *xfrm_find_acq(struct net *net, struct xfrm_mark *mark,
1513                                  u8 mode, u32 reqid, u8 proto,
1514                                  const xfrm_address_t *daddr,
1515                                  const xfrm_address_t *saddr, int create,
1516                                  unsigned short family);
1517 extern int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol);
1518
1519 #ifdef CONFIG_XFRM_MIGRATE
1520 extern int km_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
1521                       const struct xfrm_migrate *m, int num_bundles,
1522                       const struct xfrm_kmaddress *k);
1523 extern struct xfrm_state * xfrm_migrate_state_find(struct xfrm_migrate *m);
1524 extern struct xfrm_state * xfrm_state_migrate(struct xfrm_state *x,
1525                                               struct xfrm_migrate *m);
1526 extern int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
1527                         struct xfrm_migrate *m, int num_bundles,
1528                         struct xfrm_kmaddress *k);
1529 #endif
1530
1531 extern int km_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr, __be16 sport);
1532 extern void km_policy_expired(struct xfrm_policy *pol, int dir, int hard, u32 pid);
1533 extern int km_report(struct net *net, u8 proto, struct xfrm_selector *sel, xfrm_address_t *addr);
1534
1535 extern void xfrm_input_init(void);
1536 extern int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq);
1537
1538 extern void xfrm_probe_algs(void);
1539 extern int xfrm_count_auth_supported(void);
1540 extern int xfrm_count_enc_supported(void);
1541 extern struct xfrm_algo_desc *xfrm_aalg_get_byidx(unsigned int idx);
1542 extern struct xfrm_algo_desc *xfrm_ealg_get_byidx(unsigned int idx);
1543 extern struct xfrm_algo_desc *xfrm_aalg_get_byid(int alg_id);
1544 extern struct xfrm_algo_desc *xfrm_ealg_get_byid(int alg_id);
1545 extern struct xfrm_algo_desc *xfrm_calg_get_byid(int alg_id);
1546 extern struct xfrm_algo_desc *xfrm_aalg_get_byname(const char *name, int probe);
1547 extern struct xfrm_algo_desc *xfrm_ealg_get_byname(const char *name, int probe);
1548 extern struct xfrm_algo_desc *xfrm_calg_get_byname(const char *name, int probe);
1549 extern struct xfrm_algo_desc *xfrm_aead_get_byname(const char *name, int icv_len,
1550                                                    int probe);
1551
1552 struct hash_desc;
1553 struct scatterlist;
1554 typedef int (icv_update_fn_t)(struct hash_desc *, struct scatterlist *,
1555                               unsigned int);
1556
1557 static inline int xfrm_addr_cmp(const xfrm_address_t *a,
1558                                 const xfrm_address_t *b,
1559                                 int family)
1560 {
1561         switch (family) {
1562         default:
1563         case AF_INET:
1564                 return (__force u32)a->a4 - (__force u32)b->a4;
1565         case AF_INET6:
1566                 return ipv6_addr_cmp((struct in6_addr *)a,
1567                                      (struct in6_addr *)b);
1568         }
1569 }
1570
1571 static inline int xfrm_policy_id2dir(u32 index)
1572 {
1573         return index & 7;
1574 }
1575
1576 #ifdef CONFIG_XFRM
1577 static inline int xfrm_aevent_is_on(struct net *net)
1578 {
1579         struct sock *nlsk;
1580         int ret = 0;
1581
1582         rcu_read_lock();
1583         nlsk = rcu_dereference(net->xfrm.nlsk);
1584         if (nlsk)
1585                 ret = netlink_has_listeners(nlsk, XFRMNLGRP_AEVENTS);
1586         rcu_read_unlock();
1587         return ret;
1588 }
1589 #endif
1590
1591 static inline int xfrm_alg_len(const struct xfrm_algo *alg)
1592 {
1593         return sizeof(*alg) + ((alg->alg_key_len + 7) / 8);
1594 }
1595
1596 static inline int xfrm_alg_auth_len(const struct xfrm_algo_auth *alg)
1597 {
1598         return sizeof(*alg) + ((alg->alg_key_len + 7) / 8);
1599 }
1600
1601 static inline int xfrm_replay_state_esn_len(struct xfrm_replay_state_esn *replay_esn)
1602 {
1603         return sizeof(*replay_esn) + replay_esn->bmp_len * sizeof(__u32);
1604 }
1605
1606 #ifdef CONFIG_XFRM_MIGRATE
1607 static inline int xfrm_replay_clone(struct xfrm_state *x,
1608                                      struct xfrm_state *orig)
1609 {
1610         x->replay_esn = kzalloc(xfrm_replay_state_esn_len(orig->replay_esn),
1611                                 GFP_KERNEL);
1612         if (!x->replay_esn)
1613                 return -ENOMEM;
1614
1615         x->replay_esn->bmp_len = orig->replay_esn->bmp_len;
1616         x->replay_esn->replay_window = orig->replay_esn->replay_window;
1617
1618         x->preplay_esn = kmemdup(x->replay_esn,
1619                                  xfrm_replay_state_esn_len(x->replay_esn),
1620                                  GFP_KERNEL);
1621         if (!x->preplay_esn) {
1622                 kfree(x->replay_esn);
1623                 return -ENOMEM;
1624         }
1625
1626         return 0;
1627 }
1628
1629 static inline struct xfrm_algo *xfrm_algo_clone(struct xfrm_algo *orig)
1630 {
1631         return kmemdup(orig, xfrm_alg_len(orig), GFP_KERNEL);
1632 }
1633
1634 static inline struct xfrm_algo_auth *xfrm_algo_auth_clone(struct xfrm_algo_auth *orig)
1635 {
1636         return kmemdup(orig, xfrm_alg_auth_len(orig), GFP_KERNEL);
1637 }
1638
1639 static inline void xfrm_states_put(struct xfrm_state **states, int n)
1640 {
1641         int i;
1642         for (i = 0; i < n; i++)
1643                 xfrm_state_put(*(states + i));
1644 }
1645
1646 static inline void xfrm_states_delete(struct xfrm_state **states, int n)
1647 {
1648         int i;
1649         for (i = 0; i < n; i++)
1650                 xfrm_state_delete(*(states + i));
1651 }
1652 #endif
1653
1654 #ifdef CONFIG_XFRM
1655 static inline struct xfrm_state *xfrm_input_state(struct sk_buff *skb)
1656 {
1657         return skb->sp->xvec[skb->sp->len - 1];
1658 }
1659 #endif
1660
1661 static inline int xfrm_mark_get(struct nlattr **attrs, struct xfrm_mark *m)
1662 {
1663         if (attrs[XFRMA_MARK])
1664                 memcpy(m, nla_data(attrs[XFRMA_MARK]), sizeof(struct xfrm_mark));
1665         else
1666                 m->v = m->m = 0;
1667
1668         return m->v & m->m;
1669 }
1670
1671 static inline int xfrm_mark_put(struct sk_buff *skb, const struct xfrm_mark *m)
1672 {
1673         if (m->m | m->v)
1674                 NLA_PUT(skb, XFRMA_MARK, sizeof(struct xfrm_mark), m);
1675         return 0;
1676
1677 nla_put_failure:
1678         return -1;
1679 }
1680
1681 #endif  /* _NET_XFRM_H */