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/netdevice.h>
  10 #include <linux/crypto.h>
  11 #include <linux/pfkeyv2.h>
  12 #include <linux/in6.h>
  13
  14 #include <net/sock.h>
  15 #include <net/dst.h>
  16 #include <net/route.h>
  17 #include <net/ipv6.h>
  18 #include <net/ip6_fib.h>
  19
  20 #define XFRM_ALIGN8(len)        (((len) + 7) & ~7)
  21
  22 extern struct semaphore xfrm_cfg_sem;
  23
  24 /* Organization of SPD aka "XFRM rules"
  25    ------------------------------------
  26
  27    Basic objects:
  28    - policy rule, struct xfrm_policy (=SPD entry)
  29    - bundle of transformations, struct dst_entry == struct xfrm_dst (=SA bundle)
  30    - instance of a transformer, struct xfrm_state (=SA)
  31    - template to clone xfrm_state, struct xfrm_tmpl
  32
  33    SPD is plain linear list of xfrm_policy rules, ordered by priority.
  34    (To be compatible with existing pfkeyv2 implementations,
  35    many rules with priority of 0x7fffffff are allowed to exist and
  36    such rules are ordered in an unpredictable way, thanks to bsd folks.)
  37
  38    Lookup is plain linear search until the first match with selector.
  39
  40    If "action" is "block", then we prohibit the flow, otherwise:
  41    if "xfrms_nr" is zero, the flow passes untransformed. Otherwise,
  42    policy entry has list of up to XFRM_MAX_DEPTH transformations,
  43    described by templates xfrm_tmpl. Each template is resolved
  44    to a complete xfrm_state (see below) and we pack bundle of transformations
  45    to a dst_entry returned to requestor.
  46
  47    dst -. xfrm  .-> xfrm_state #1
  48     |---. child .-> dst -. xfrm .-> xfrm_state #2
  49                      |---. child .-> dst -. xfrm .-> xfrm_state #3
  50                                       |---. child .-> NULL
  51
  52    Bundles are cached at xrfm_policy struct (field ->bundles).
  53
  54
  55    Resolution of xrfm_tmpl
  56    -----------------------
  57    Template contains:
  58    1. ->mode            Mode: transport or tunnel
  59    2. ->id.proto        Protocol: AH/ESP/IPCOMP
  60    3. ->id.daddr        Remote tunnel endpoint, ignored for transport mode.
  61       Q: allow to resolve security gateway?
  62    4. ->id.spi          If not zero, static SPI.
  63    5. ->saddr           Local tunnel endpoint, ignored for transport mode.
  64    6. ->algos           List of allowed algos. Plain bitmask now.
  65       Q: ealgos, aalgos, calgos. What a mess...
  66    7. ->share           Sharing mode.
  67       Q: how to implement private sharing mode? To add struct sock* to
  68       flow id?
  69
  70    Having this template we search through SAD searching for entries
  71    with appropriate mode/proto/algo, permitted by selector.
  72    If no appropriate entry found, it is requested from key manager.
  73
  74    PROBLEMS:
  75    Q: How to find all the bundles referring to a physical path for
  76       PMTU discovery? Seems, dst should contain list of all parents...
  77       and enter to infinite locking hierarchy disaster.
  78       No! It is easier, we will not search for them, let them find us.
  79       We add genid to each dst plus pointer to genid of raw IP route,
  80       pmtu disc will update pmtu on raw IP route and increase its genid.
  81       dst_check() will see this for top level and trigger resyncing
  82       metrics. Plus, it will be made via sk->sk_dst_cache. Solved.
  83  */
  84
  85 /* Full description of state of transformer. */
  86 struct xfrm_state
  87 {
  88         /* Note: bydst is re-used during gc */
  89         struct list_head        bydst;
  90         struct list_head        byspi;
  91
  92         atomic_t                refcnt;
  93         spinlock_t              lock;
  94
  95         struct xfrm_id          id;
  96         struct xfrm_selector    sel;
  97
  98         /* Key manger bits */
  99         struct {
 100                 u8              state;
 101                 u8              dying;
 102                 u32             seq;
 103         } km;
 104
 105         /* Parameters of this state. */
 106         struct {
 107                 u32             reqid;
 108                 u8              mode;
 109                 u8              replay_window;
 110                 u8              aalgo, ealgo, calgo;
 111                 u8              flags;
 112                 u16             family;
 113                 xfrm_address_t  saddr;
 114                 int             header_len;
 115                 int             trailer_len;
 116         } props;
 117
 118         struct xfrm_lifetime_cfg lft;
 119
 120         /* Data for transformer */
 121         struct xfrm_algo        *aalg;
 122         struct xfrm_algo        *ealg;
 123         struct xfrm_algo        *calg;
 124
 125         /* Data for encapsulator */
 126         struct xfrm_encap_tmpl  *encap;
 127
 128         /* IPComp needs an IPIP tunnel for handling uncompressed packets */
 129         struct xfrm_state       *tunnel;
 130
 131         /* If a tunnel, number of users + 1 */
 132         atomic_t                tunnel_users;
 133
 134         /* State for replay detection */
 135         struct xfrm_replay_state replay;
 136
 137         /* Statistics */
 138         struct xfrm_stats       stats;
 139
 140         struct xfrm_lifetime_cur curlft;
 141         struct timer_list       timer;
 142
 143         /* Reference to data common to all the instances of this
 144          * transformer. */
 145         struct xfrm_type        *type;
 146
 147         /* Security context */
 148         struct xfrm_sec_ctx     *security;
 149
 150         /* Private data of this transformer, format is opaque,
 151          * interpreted by xfrm_type methods. */
 152         void                    *data;
 153 };
 154
 155 enum {
 156         XFRM_STATE_VOID,
 157         XFRM_STATE_ACQ,
 158         XFRM_STATE_VALID,
 159         XFRM_STATE_ERROR,
 160         XFRM_STATE_EXPIRED,
 161         XFRM_STATE_DEAD
 162 };
 163
 164 /* callback structure passed from either netlink or pfkey */
 165 struct km_event
 166 {
 167         union {
 168                 u32 hard;
 169                 u32 proto;
 170                 u32 byid;
 171         } data;
 172
 173         u32     seq;
 174         u32     pid;
 175         u32     event;
 176 };
 177
 178 struct xfrm_type;
 179 struct xfrm_dst;
 180 struct xfrm_policy_afinfo {
 181         unsigned short          family;
 182         rwlock_t                lock;
 183         struct xfrm_type_map    *type_map;
 184         struct dst_ops          *dst_ops;
 185         void                    (*garbage_collect)(void);
 186         int                     (*dst_lookup)(struct xfrm_dst **dst, struct flowi *fl);
 187         struct dst_entry        *(*find_bundle)(struct flowi *fl, struct xfrm_policy *policy);
 188         int                     (*bundle_create)(struct xfrm_policy *policy,
 189                                                  struct xfrm_state **xfrm,
 190                                                  int nx,
 191                                                  struct flowi *fl,
 192                                                  struct dst_entry **dst_p);
 193         void                    (*decode_session)(struct sk_buff *skb,
 194                                                   struct flowi *fl);
 195 };
 196
 197 extern int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo);
 198 extern int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo);
 199 extern void km_policy_notify(struct xfrm_policy *xp, int dir, struct km_event *c);
 200 extern void km_state_notify(struct xfrm_state *x, struct km_event *c);
 201
 202 #define XFRM_ACQ_EXPIRES        30
 203
 204 struct xfrm_tmpl;
 205 struct xfrm_state_afinfo {
 206         unsigned short          family;
 207         rwlock_t                lock;
 208         struct list_head        *state_bydst;
 209         struct list_head        *state_byspi;
 210         int                     (*init_flags)(struct xfrm_state *x);
 211         void                    (*init_tempsel)(struct xfrm_state *x, struct flowi *fl,
 212                                                 struct xfrm_tmpl *tmpl,
 213                                                 xfrm_address_t *daddr, xfrm_address_t *saddr);
 214         struct xfrm_state       *(*state_lookup)(xfrm_address_t *daddr, u32 spi, u8 proto);
 215         struct xfrm_state       *(*find_acq)(u8 mode, u32 reqid, u8 proto,
 216                                              xfrm_address_t *daddr, xfrm_address_t *saddr,
 217                                              int create);
 218 };
 219
 220 extern int xfrm_state_register_afinfo(struct xfrm_state_afinfo *afinfo);
 221 extern int xfrm_state_unregister_afinfo(struct xfrm_state_afinfo *afinfo);
 222
 223 extern void xfrm_state_delete_tunnel(struct xfrm_state *x);
 224
 225 struct xfrm_decap_state;
 226 struct xfrm_type
 227 {
 228         char                    *description;
 229         struct module           *owner;
 230         __u8                    proto;
 231
 232         int                     (*init_state)(struct xfrm_state *x);
 233         void                    (*destructor)(struct xfrm_state *);
 234         int                     (*input)(struct xfrm_state *, struct xfrm_decap_state *, struct sk_buff *skb);
 235         int                     (*post_input)(struct xfrm_state *, struct xfrm_decap_state *, struct sk_buff *skb);
 236         int                     (*output)(struct xfrm_state *, struct sk_buff *pskb);
 237         /* Estimate maximal size of result of transformation of a dgram */
 238         u32                     (*get_max_size)(struct xfrm_state *, int size);
 239 };
 240
 241 struct xfrm_type_map {
 242         rwlock_t                lock;
 243         struct xfrm_type        *map[256];
 244 };
 245
 246 extern int xfrm_register_type(struct xfrm_type *type, unsigned short family);
 247 extern int xfrm_unregister_type(struct xfrm_type *type, unsigned short family);
 248 extern struct xfrm_type *xfrm_get_type(u8 proto, unsigned short family);
 249 extern void xfrm_put_type(struct xfrm_type *type);
 250
 251 struct xfrm_tmpl
 252 {
 253 /* id in template is interpreted as:
 254  * daddr - destination of tunnel, may be zero for transport mode.
 255  * spi   - zero to acquire spi. Not zero if spi is static, then
 256  *         daddr must be fixed too.
 257  * proto - AH/ESP/IPCOMP
 258  */
 259         struct xfrm_id          id;
 260
 261 /* Source address of tunnel. Ignored, if it is not a tunnel. */
 262         xfrm_address_t          saddr;
 263
 264         __u32                   reqid;
 265
 266 /* Mode: transport/tunnel */
 267         __u8                    mode;
 268
 269 /* Sharing mode: unique, this session only, this user only etc. */
 270         __u8                    share;
 271
 272 /* May skip this transfomration if no SA is found */
 273         __u8                    optional;
 274
 275 /* Bit mask of algos allowed for acquisition */
 276         __u32                   aalgos;
 277         __u32                   ealgos;
 278         __u32                   calgos;
 279 };
 280
 281 #define XFRM_MAX_DEPTH          4
 282
 283 struct xfrm_policy
 284 {
 285         struct xfrm_policy      *next;
 286         struct list_head        list;
 287
 288         /* This lock only affects elements except for entry. */
 289         rwlock_t                lock;
 290         atomic_t                refcnt;
 291         struct timer_list       timer;
 292
 293         u32                     priority;
 294         u32                     index;
 295         struct xfrm_selector    selector;
 296         struct xfrm_lifetime_cfg lft;
 297         struct xfrm_lifetime_cur curlft;
 298         struct dst_entry       *bundles;
 299         __u16                   family;
 300         __u8                    action;
 301         __u8                    flags;
 302         __u8                    dead;
 303         __u8                    xfrm_nr;
 304         struct xfrm_sec_ctx     *security;
 305         struct xfrm_tmpl        xfrm_vec[XFRM_MAX_DEPTH];
 306 };
 307
 308 #define XFRM_KM_TIMEOUT         30
 309
 310 struct xfrm_mgr
 311 {
 312         struct list_head        list;
 313         char                    *id;
 314         int                     (*notify)(struct xfrm_state *x, struct km_event *c);
 315         int                     (*acquire)(struct xfrm_state *x, struct xfrm_tmpl *, struct xfrm_policy *xp, int dir);
 316         struct xfrm_policy      *(*compile_policy)(u16 family, int opt, u8 *data, int len, int *dir);
 317         int                     (*new_mapping)(struct xfrm_state *x, xfrm_address_t *ipaddr, u16 sport);
 318         int                     (*notify_policy)(struct xfrm_policy *x, int dir, struct km_event *c);
 319 };
 320
 321 extern int xfrm_register_km(struct xfrm_mgr *km);
 322 extern int xfrm_unregister_km(struct xfrm_mgr *km);
 323
 324
 325 extern struct xfrm_policy *xfrm_policy_list[XFRM_POLICY_MAX*2];
 326
 327 static inline void xfrm_pol_hold(struct xfrm_policy *policy)
 328 {
 329         if (likely(policy != NULL))
 330                 atomic_inc(&policy->refcnt);
 331 }
 332
 333 extern void __xfrm_policy_destroy(struct xfrm_policy *policy);
 334
 335 static inline void xfrm_pol_put(struct xfrm_policy *policy)
 336 {
 337         if (atomic_dec_and_test(&policy->refcnt))
 338                 __xfrm_policy_destroy(policy);
 339 }
 340
 341 #define XFRM_DST_HSIZE          1024
 342
 343 static __inline__
 344 unsigned __xfrm4_dst_hash(xfrm_address_t *addr)
 345 {
 346         unsigned h;
 347         h = ntohl(addr->a4);
 348         h = (h ^ (h>>16)) % XFRM_DST_HSIZE;
 349         return h;
 350 }
 351
 352 static __inline__
 353 unsigned __xfrm6_dst_hash(xfrm_address_t *addr)
 354 {
 355         unsigned h;
 356         h = ntohl(addr->a6[2]^addr->a6[3]);
 357         h = (h ^ (h>>16)) % XFRM_DST_HSIZE;
 358         return h;
 359 }
 360
 361 static __inline__
 362 unsigned xfrm_dst_hash(xfrm_address_t *addr, unsigned short family)
 363 {
 364         switch (family) {
 365         case AF_INET:
 366                 return __xfrm4_dst_hash(addr);
 367         case AF_INET6:
 368                 return __xfrm6_dst_hash(addr);
 369         }
 370         return 0;
 371 }
 372
 373 static __inline__
 374 unsigned __xfrm4_spi_hash(xfrm_address_t *addr, u32 spi, u8 proto)
 375 {
 376         unsigned h;
 377         h = ntohl(addr->a4^spi^proto);
 378         h = (h ^ (h>>10) ^ (h>>20)) % XFRM_DST_HSIZE;
 379         return h;
 380 }
 381
 382 static __inline__
 383 unsigned __xfrm6_spi_hash(xfrm_address_t *addr, u32 spi, u8 proto)
 384 {
 385         unsigned h;
 386         h = ntohl(addr->a6[2]^addr->a6[3]^spi^proto);
 387         h = (h ^ (h>>10) ^ (h>>20)) % XFRM_DST_HSIZE;
 388         return h;
 389 }
 390
 391 static __inline__
 392 unsigned xfrm_spi_hash(xfrm_address_t *addr, u32 spi, u8 proto, unsigned short family)
 393 {
 394         switch (family) {
 395         case AF_INET:
 396                 return __xfrm4_spi_hash(addr, spi, proto);
 397         case AF_INET6:
 398                 return __xfrm6_spi_hash(addr, spi, proto);
 399         }
 400         return 0;       /*XXX*/
 401 }
 402
 403 extern void __xfrm_state_destroy(struct xfrm_state *);
 404
 405 static inline void xfrm_state_put(struct xfrm_state *x)
 406 {
 407         if (atomic_dec_and_test(&x->refcnt))
 408                 __xfrm_state_destroy(x);
 409 }
 410
 411 static inline void xfrm_state_hold(struct xfrm_state *x)
 412 {
 413         atomic_inc(&x->refcnt);
 414 }
 415
 416 static __inline__ int addr_match(void *token1, void *token2, int prefixlen)
 417 {
 418         __u32 *a1 = token1;
 419         __u32 *a2 = token2;
 420         int pdw;
 421         int pbi;
 422
 423         pdw = prefixlen >> 5;     /* num of whole __u32 in prefix */
 424         pbi = prefixlen &  0x1f;  /* num of bits in incomplete u32 in prefix */
 425
 426         if (pdw)
 427                 if (memcmp(a1, a2, pdw << 2))
 428                         return 0;
 429
 430         if (pbi) {
 431                 __u32 mask;
 432
 433                 mask = htonl((0xffffffff) << (32 - pbi));
 434
 435                 if ((a1[pdw] ^ a2[pdw]) & mask)
 436                         return 0;
 437         }
 438
 439         return 1;
 440 }
 441
 442 static __inline__
 443 u16 xfrm_flowi_sport(struct flowi *fl)
 444 {
 445         u16 port;
 446         switch(fl->proto) {
 447         case IPPROTO_TCP:
 448         case IPPROTO_UDP:
 449         case IPPROTO_SCTP:
 450                 port = fl->fl_ip_sport;
 451                 break;
 452         case IPPROTO_ICMP:
 453         case IPPROTO_ICMPV6:
 454                 port = htons(fl->fl_icmp_type);
 455                 break;
 456         default:
 457                 port = 0;       /*XXX*/
 458         }
 459         return port;
 460 }
 461
 462 static __inline__
 463 u16 xfrm_flowi_dport(struct flowi *fl)
 464 {
 465         u16 port;
 466         switch(fl->proto) {
 467         case IPPROTO_TCP:
 468         case IPPROTO_UDP:
 469         case IPPROTO_SCTP:
 470                 port = fl->fl_ip_dport;
 471                 break;
 472         case IPPROTO_ICMP:
 473         case IPPROTO_ICMPV6:
 474                 port = htons(fl->fl_icmp_code);
 475                 break;
 476         default:
 477                 port = 0;       /*XXX*/
 478         }
 479         return port;
 480 }
 481
 482 static inline int
 483 __xfrm4_selector_match(struct xfrm_selector *sel, struct flowi *fl)
 484 {
 485         return  addr_match(&fl->fl4_dst, &sel->daddr, sel->prefixlen_d) &&
 486                 addr_match(&fl->fl4_src, &sel->saddr, sel->prefixlen_s) &&
 487                 !((xfrm_flowi_dport(fl) ^ sel->dport) & sel->dport_mask) &&
 488                 !((xfrm_flowi_sport(fl) ^ sel->sport) & sel->sport_mask) &&
 489                 (fl->proto == sel->proto || !sel->proto) &&
 490                 (fl->oif == sel->ifindex || !sel->ifindex);
 491 }
 492
 493 static inline int
 494 __xfrm6_selector_match(struct xfrm_selector *sel, struct flowi *fl)
 495 {
 496         return  addr_match(&fl->fl6_dst, &sel->daddr, sel->prefixlen_d) &&
 497                 addr_match(&fl->fl6_src, &sel->saddr, sel->prefixlen_s) &&
 498                 !((xfrm_flowi_dport(fl) ^ sel->dport) & sel->dport_mask) &&
 499                 !((xfrm_flowi_sport(fl) ^ sel->sport) & sel->sport_mask) &&
 500                 (fl->proto == sel->proto || !sel->proto) &&
 501                 (fl->oif == sel->ifindex || !sel->ifindex);
 502 }
 503
 504 static inline int
 505 xfrm_selector_match(struct xfrm_selector *sel, struct flowi *fl,
 506                     unsigned short family)
 507 {
 508         switch (family) {
 509         case AF_INET:
 510                 return __xfrm4_selector_match(sel, fl);
 511         case AF_INET6:
 512                 return __xfrm6_selector_match(sel, fl);
 513         }
 514         return 0;
 515 }
 516
 517 #ifdef CONFIG_SECURITY_NETWORK_XFRM
 518 /*      If neither has a context --> match
 519  *      Otherwise, both must have a context and the sids, doi, alg must match
 520  */
 521 static inline int xfrm_sec_ctx_match(struct xfrm_sec_ctx *s1, struct xfrm_sec_ctx *s2)
 522 {
 523         return ((!s1 && !s2) ||
 524                 (s1 && s2 &&
 525                  (s1->ctx_sid == s2->ctx_sid) &&
 526                  (s1->ctx_doi == s2->ctx_doi) &&
 527                  (s1->ctx_alg == s2->ctx_alg)));
 528 }
 529 #else
 530 static inline int xfrm_sec_ctx_match(struct xfrm_sec_ctx *s1, struct xfrm_sec_ctx *s2)
 531 {
 532         return 1;
 533 }
 534 #endif
 535
 536 /* A struct encoding bundle of transformations to apply to some set of flow.
 537  *
 538  * dst->child points to the next element of bundle.
 539  * dst->xfrm  points to an instanse of transformer.
 540  *
 541  * Due to unfortunate limitations of current routing cache, which we
 542  * have no time to fix, it mirrors struct rtable and bound to the same
 543  * routing key, including saddr,daddr. However, we can have many of
 544  * bundles differing by session id. All the bundles grow from a parent
 545  * policy rule.
 546  */
 547 struct xfrm_dst
 548 {
 549         union {
 550                 struct xfrm_dst         *next;
 551                 struct dst_entry        dst;
 552                 struct rtable           rt;
 553                 struct rt6_info         rt6;
 554         } u;
 555         struct dst_entry *route;
 556         u32 route_mtu_cached;
 557         u32 child_mtu_cached;
 558         u32 route_cookie;
 559         u32 path_cookie;
 560 };
 561
 562 static inline void xfrm_dst_destroy(struct xfrm_dst *xdst)
 563 {
 564         dst_release(xdst->route);
 565         if (likely(xdst->u.dst.xfrm))
 566                 xfrm_state_put(xdst->u.dst.xfrm);
 567 }
 568
 569 extern void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev);
 570
 571 /* Decapsulation state, used by the input to store data during
 572  * decapsulation procedure, to be used later (during the policy
 573  * check
 574  */
 575 struct xfrm_decap_state {
 576         char    decap_data[20];
 577         __u16   decap_type;
 578 };
 579
 580 struct sec_decap_state {
 581         struct xfrm_state       *xvec;
 582         struct xfrm_decap_state decap;
 583 };
 584
 585 struct sec_path
 586 {
 587         atomic_t                refcnt;
 588         int                     len;
 589         struct sec_decap_state  x[XFRM_MAX_DEPTH];
 590 };
 591
 592 static inline struct sec_path *
 593 secpath_get(struct sec_path *sp)
 594 {
 595         if (sp)
 596                 atomic_inc(&sp->refcnt);
 597         return sp;
 598 }
 599
 600 extern void __secpath_destroy(struct sec_path *sp);
 601
 602 static inline void
 603 secpath_put(struct sec_path *sp)
 604 {
 605         if (sp && atomic_dec_and_test(&sp->refcnt))
 606                 __secpath_destroy(sp);
 607 }
 608
 609 extern struct sec_path *secpath_dup(struct sec_path *src);
 610
 611 static inline void
 612 secpath_reset(struct sk_buff *skb)
 613 {
 614 #ifdef CONFIG_XFRM
 615         secpath_put(skb->sp);
 616         skb->sp = NULL;
 617 #endif
 618 }
 619
 620 static inline int
 621 __xfrm4_state_addr_cmp(struct xfrm_tmpl *tmpl, struct xfrm_state *x)
 622 {
 623         return  (tmpl->saddr.a4 &&
 624                  tmpl->saddr.a4 != x->props.saddr.a4);
 625 }
 626
 627 static inline int
 628 __xfrm6_state_addr_cmp(struct xfrm_tmpl *tmpl, struct xfrm_state *x)
 629 {
 630         return  (!ipv6_addr_any((struct in6_addr*)&tmpl->saddr) &&
 631                  ipv6_addr_cmp((struct in6_addr *)&tmpl->saddr, (struct in6_addr*)&x->props.saddr));
 632 }
 633
 634 static inline int
 635 xfrm_state_addr_cmp(struct xfrm_tmpl *tmpl, struct xfrm_state *x, unsigned short family)
 636 {
 637         switch (family) {
 638         case AF_INET:
 639                 return __xfrm4_state_addr_cmp(tmpl, x);
 640         case AF_INET6:
 641                 return __xfrm6_state_addr_cmp(tmpl, x);
 642         }
 643         return !0;
 644 }
 645
 646 #ifdef CONFIG_XFRM
 647
 648 extern int __xfrm_policy_check(struct sock *, int dir, struct sk_buff *skb, unsigned short family);
 649
 650 static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
 651 {
 652         if (sk && sk->sk_policy[XFRM_POLICY_IN])
 653                 return __xfrm_policy_check(sk, dir, skb, family);
 654
 655         return  (!xfrm_policy_list[dir] && !skb->sp) ||
 656                 (skb->dst->flags & DST_NOPOLICY) ||
 657                 __xfrm_policy_check(sk, dir, skb, family);
 658 }
 659
 660 static inline int xfrm4_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
 661 {
 662         return xfrm_policy_check(sk, dir, skb, AF_INET);
 663 }
 664
 665 static inline int xfrm6_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
 666 {
 667         return xfrm_policy_check(sk, dir, skb, AF_INET6);
 668 }
 669
 670
 671 extern int __xfrm_route_forward(struct sk_buff *skb, unsigned short family);
 672
 673 static inline int xfrm_route_forward(struct sk_buff *skb, unsigned short family)
 674 {
 675         return  !xfrm_policy_list[XFRM_POLICY_OUT] ||
 676                 (skb->dst->flags & DST_NOXFRM) ||
 677                 __xfrm_route_forward(skb, family);
 678 }
 679
 680 static inline int xfrm4_route_forward(struct sk_buff *skb)
 681 {
 682         return xfrm_route_forward(skb, AF_INET);
 683 }
 684
 685 static inline int xfrm6_route_forward(struct sk_buff *skb)
 686 {
 687         return xfrm_route_forward(skb, AF_INET6);
 688 }
 689
 690 extern int __xfrm_sk_clone_policy(struct sock *sk);
 691
 692 static inline int xfrm_sk_clone_policy(struct sock *sk)
 693 {
 694         if (unlikely(sk->sk_policy[0] || sk->sk_policy[1]))
 695                 return __xfrm_sk_clone_policy(sk);
 696         return 0;
 697 }
 698
 699 extern int xfrm_policy_delete(struct xfrm_policy *pol, int dir);
 700
 701 static inline void xfrm_sk_free_policy(struct sock *sk)
 702 {
 703         if (unlikely(sk->sk_policy[0] != NULL)) {
 704                 xfrm_policy_delete(sk->sk_policy[0], XFRM_POLICY_MAX);
 705                 sk->sk_policy[0] = NULL;
 706         }
 707         if (unlikely(sk->sk_policy[1] != NULL)) {
 708                 xfrm_policy_delete(sk->sk_policy[1], XFRM_POLICY_MAX+1);
 709                 sk->sk_policy[1] = NULL;
 710         }
 711 }
 712
 713 #else
 714
 715 static inline void xfrm_sk_free_policy(struct sock *sk) {}
 716 static inline int xfrm_sk_clone_policy(struct sock *sk) { return 0; }
 717 static inline int xfrm6_route_forward(struct sk_buff *skb) { return 1; }
 718 static inline int xfrm4_route_forward(struct sk_buff *skb) { return 1; }
 719 static inline int xfrm6_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
 720 {
 721         return 1;
 722 }
 723 static inline int xfrm4_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
 724 {
 725         return 1;
 726 }
 727 static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
 728 {
 729         return 1;
 730 }
 731 #endif
 732
 733 static __inline__
 734 xfrm_address_t *xfrm_flowi_daddr(struct flowi *fl, unsigned short family)
 735 {
 736         switch (family){
 737         case AF_INET:
 738                 return (xfrm_address_t *)&fl->fl4_dst;
 739         case AF_INET6:
 740                 return (xfrm_address_t *)&fl->fl6_dst;
 741         }
 742         return NULL;
 743 }
 744
 745 static __inline__
 746 xfrm_address_t *xfrm_flowi_saddr(struct flowi *fl, unsigned short family)
 747 {
 748         switch (family){
 749         case AF_INET:
 750                 return (xfrm_address_t *)&fl->fl4_src;
 751         case AF_INET6:
 752                 return (xfrm_address_t *)&fl->fl6_src;
 753         }
 754         return NULL;
 755 }
 756
 757 static __inline__ int
 758 __xfrm4_state_addr_check(struct xfrm_state *x,
 759                          xfrm_address_t *daddr, xfrm_address_t *saddr)
 760 {
 761         if (daddr->a4 == x->id.daddr.a4 &&
 762             (saddr->a4 == x->props.saddr.a4 || !saddr->a4 || !x->props.saddr.a4))
 763                 return 1;
 764         return 0;
 765 }
 766
 767 static __inline__ int
 768 __xfrm6_state_addr_check(struct xfrm_state *x,
 769                          xfrm_address_t *daddr, xfrm_address_t *saddr)
 770 {
 771         if (!ipv6_addr_cmp((struct in6_addr *)daddr, (struct in6_addr *)&x->id.daddr) &&
 772             (!ipv6_addr_cmp((struct in6_addr *)saddr, (struct in6_addr *)&x->props.saddr)||
 773              ipv6_addr_any((struct in6_addr *)saddr) ||
 774              ipv6_addr_any((struct in6_addr *)&x->props.saddr)))
 775                 return 1;
 776         return 0;
 777 }
 778
 779 static __inline__ int
 780 xfrm_state_addr_check(struct xfrm_state *x,
 781                       xfrm_address_t *daddr, xfrm_address_t *saddr,
 782                       unsigned short family)
 783 {
 784         switch (family) {
 785         case AF_INET:
 786                 return __xfrm4_state_addr_check(x, daddr, saddr);
 787         case AF_INET6:
 788                 return __xfrm6_state_addr_check(x, daddr, saddr);
 789         }
 790         return 0;
 791 }
 792
 793 static inline int xfrm_state_kern(struct xfrm_state *x)
 794 {
 795         return atomic_read(&x->tunnel_users);
 796 }
 797
 798 /*
 799  * xfrm algorithm information
 800  */
 801 struct xfrm_algo_auth_info {
 802         u16 icv_truncbits;
 803         u16 icv_fullbits;
 804 };
 805
 806 struct xfrm_algo_encr_info {
 807         u16 blockbits;
 808         u16 defkeybits;
 809 };
 810
 811 struct xfrm_algo_comp_info {
 812         u16 threshold;
 813 };
 814
 815 struct xfrm_algo_desc {
 816         char *name;
 817         u8 available:1;
 818         union {
 819                 struct xfrm_algo_auth_info auth;
 820                 struct xfrm_algo_encr_info encr;
 821                 struct xfrm_algo_comp_info comp;
 822         } uinfo;
 823         struct sadb_alg desc;
 824 };
 825
 826 /* XFRM tunnel handlers.  */
 827 struct xfrm_tunnel {
 828         int (*handler)(struct sk_buff *skb);
 829         void (*err_handler)(struct sk_buff *skb, __u32 info);
 830 };
 831
 832 struct xfrm6_tunnel {
 833         int (*handler)(struct sk_buff **pskb, unsigned int *nhoffp);
 834         void (*err_handler)(struct sk_buff *skb, struct inet6_skb_parm *opt,
 835                             int type, int code, int offset, __u32 info);
 836 };
 837
 838 extern void xfrm_init(void);
 839 extern void xfrm4_init(void);
 840 extern void xfrm6_init(void);
 841 extern void xfrm6_fini(void);
 842 extern void xfrm_state_init(void);
 843 extern void xfrm4_state_init(void);
 844 extern void xfrm6_state_init(void);
 845 extern void xfrm6_state_fini(void);
 846
 847 extern int xfrm_state_walk(u8 proto, int (*func)(struct xfrm_state *, int, void*), void *);
 848 extern struct xfrm_state *xfrm_state_alloc(void);
 849 extern struct xfrm_state *xfrm_state_find(xfrm_address_t *daddr, xfrm_address_t *saddr,
 850                                           struct flowi *fl, struct xfrm_tmpl *tmpl,
 851                                           struct xfrm_policy *pol, int *err,
 852                                           unsigned short family);
 853 extern int xfrm_state_check_expire(struct xfrm_state *x);
 854 extern void xfrm_state_insert(struct xfrm_state *x);
 855 extern int xfrm_state_add(struct xfrm_state *x);
 856 extern int xfrm_state_update(struct xfrm_state *x);
 857 extern struct xfrm_state *xfrm_state_lookup(xfrm_address_t *daddr, u32 spi, u8 proto, unsigned short family);
 858 extern struct xfrm_state *xfrm_find_acq_byseq(u32 seq);
 859 extern int xfrm_state_delete(struct xfrm_state *x);
 860 extern void xfrm_state_flush(u8 proto);
 861 extern int xfrm_replay_check(struct xfrm_state *x, u32 seq);
 862 extern void xfrm_replay_advance(struct xfrm_state *x, u32 seq);
 863 extern int xfrm_state_check(struct xfrm_state *x, struct sk_buff *skb);
 864 extern int xfrm_state_mtu(struct xfrm_state *x, int mtu);
 865 extern int xfrm_init_state(struct xfrm_state *x);
 866 extern int xfrm4_rcv(struct sk_buff *skb);
 867 extern int xfrm4_output(struct sk_buff *skb);
 868 extern int xfrm4_tunnel_register(struct xfrm_tunnel *handler);
 869 extern int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler);
 870 extern int xfrm6_rcv_spi(struct sk_buff **pskb, unsigned int *nhoffp, u32 spi);
 871 extern int xfrm6_rcv(struct sk_buff **pskb, unsigned int *nhoffp);
 872 extern int xfrm6_tunnel_register(struct xfrm6_tunnel *handler);
 873 extern int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler);
 874 extern u32 xfrm6_tunnel_alloc_spi(xfrm_address_t *saddr);
 875 extern void xfrm6_tunnel_free_spi(xfrm_address_t *saddr);
 876 extern u32 xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr);
 877 extern int xfrm6_output(struct sk_buff *skb);
 878
 879 #ifdef CONFIG_XFRM
 880 extern int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type);
 881 extern int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen);
 882 extern int xfrm_dst_lookup(struct xfrm_dst **dst, struct flowi *fl, unsigned short family);
 883 #else
 884 static inline int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen)
 885 {
 886         return -ENOPROTOOPT;
 887 }
 888
 889 static inline int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type)
 890 {
 891         /* should not happen */
 892         kfree_skb(skb);
 893         return 0;
 894 }
 895 static inline int xfrm_dst_lookup(struct xfrm_dst **dst, struct flowi *fl, unsigned short family)
 896 {
 897         return -EINVAL;
 898 }
 899 #endif
 900
 901 struct xfrm_policy *xfrm_policy_alloc(gfp_t gfp);
 902 extern int xfrm_policy_walk(int (*func)(struct xfrm_policy *, int, int, void*), void *);
 903 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl);
 904 struct xfrm_policy *xfrm_policy_bysel_ctx(int dir, struct xfrm_selector *sel,
 905                                           struct xfrm_sec_ctx *ctx, int delete);
 906 struct xfrm_policy *xfrm_policy_byid(int dir, u32 id, int delete);
 907 void xfrm_policy_flush(void);
 908 u32 xfrm_get_acqseq(void);
 909 void xfrm_alloc_spi(struct xfrm_state *x, u32 minspi, u32 maxspi);
 910 struct xfrm_state * xfrm_find_acq(u8 mode, u32 reqid, u8 proto,
 911                                   xfrm_address_t *daddr, xfrm_address_t *saddr,
 912                                   int create, unsigned short family);
 913 extern void xfrm_policy_flush(void);
 914 extern int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol);
 915 extern int xfrm_flush_bundles(void);
 916 extern void xfrm_flush_all_bundles(void);
 917 extern int xfrm_bundle_ok(struct xfrm_dst *xdst, struct flowi *fl, int family);
 918 extern void xfrm_init_pmtu(struct dst_entry *dst);
 919
 920 extern wait_queue_head_t km_waitq;
 921 extern int km_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr, u16 sport);
 922 extern void km_policy_expired(struct xfrm_policy *pol, int dir, int hard);
 923
 924 extern void xfrm_input_init(void);
 925 extern int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, u32 *spi, u32 *seq);
 926
 927 extern void xfrm_probe_algs(void);
 928 extern int xfrm_count_auth_supported(void);
 929 extern int xfrm_count_enc_supported(void);
 930 extern struct xfrm_algo_desc *xfrm_aalg_get_byidx(unsigned int idx);
 931 extern struct xfrm_algo_desc *xfrm_ealg_get_byidx(unsigned int idx);
 932 extern struct xfrm_algo_desc *xfrm_aalg_get_byid(int alg_id);
 933 extern struct xfrm_algo_desc *xfrm_ealg_get_byid(int alg_id);
 934 extern struct xfrm_algo_desc *xfrm_calg_get_byid(int alg_id);
 935 extern struct xfrm_algo_desc *xfrm_aalg_get_byname(char *name, int probe);
 936 extern struct xfrm_algo_desc *xfrm_ealg_get_byname(char *name, int probe);
 937 extern struct xfrm_algo_desc *xfrm_calg_get_byname(char *name, int probe);
 938
 939 struct crypto_tfm;
 940 typedef void (icv_update_fn_t)(struct crypto_tfm *, struct scatterlist *, unsigned int);
 941
 942 extern void skb_icv_walk(const struct sk_buff *skb, struct crypto_tfm *tfm,
 943                          int offset, int len, icv_update_fn_t icv_update);
 944
 945 static inline int xfrm_addr_cmp(xfrm_address_t *a, xfrm_address_t *b,
 946                                 int family)
 947 {
 948         switch (family) {
 949         default:
 950         case AF_INET:
 951                 return a->a4 - b->a4;
 952         case AF_INET6:
 953                 return ipv6_addr_cmp((struct in6_addr *)a,
 954                                      (struct in6_addr *)b);
 955         }
 956 }
 957
 958 static inline int xfrm_policy_id2dir(u32 index)
 959 {
 960         return index & 7;
 961 }
 962
 963 #endif  /* _NET_XFRM_H */