include/net/xfrm.h

   1 #ifndef _NET_XFRM_H
   2 #define _NET_XFRM_H
   3
   4 #include <linux/compiler.h>
   5 #include <linux/in.h>
   6 #include <linux/xfrm.h>
   7 #include <linux/spinlock.h>
   8 #include <linux/list.h>
   9 #include <linux/skbuff.h>
  10 #include <linux/socket.h>
  11 #include <linux/crypto.h>
  12 #include <linux/pfkeyv2.h>
  13 #include <linux/in6.h>
  14
  15 #include <net/sock.h>
  16 #include <net/dst.h>
  17 #include <net/route.h>
  18 #include <net/ipv6.h>
  19 #include <net/ip6_fib.h>
  20
  21 #define XFRM_ALIGN8(len)        (((len) + 7) & ~7)
  22
  23 extern struct semaphore xfrm_cfg_sem;
  24
  25 /* Organization of SPD aka "XFRM rules"
  26    ------------------------------------
  27
  28    Basic objects:
  29    - policy rule, struct xfrm_policy (=SPD entry)
  30    - bundle of transformations, struct dst_entry == struct xfrm_dst (=SA bundle)
  31    - instance of a transformer, struct xfrm_state (=SA)
  32    - template to clone xfrm_state, struct xfrm_tmpl
  33
  34    SPD is plain linear list of xfrm_policy rules, ordered by priority.
  35    (To be compatible with existing pfkeyv2 implementations,
  36    many rules with priority of 0x7fffffff are allowed to exist and
  37    such rules are ordered in an unpredictable way, thanks to bsd folks.)
  38
  39    Lookup is plain linear search until the first match with selector.
  40
  41    If "action" is "block", then we prohibit the flow, otherwise:
  42    if "xfrms_nr" is zero, the flow passes untransformed. Otherwise,
  43    policy entry has list of up to XFRM_MAX_DEPTH transformations,
  44    described by templates xfrm_tmpl. Each template is resolved
  45    to a complete xfrm_state (see below) and we pack bundle of transformations
  46    to a dst_entry returned to requestor.
  47
  48    dst -. xfrm  .-> xfrm_state #1
  49     |---. child .-> dst -. xfrm .-> xfrm_state #2
  50                      |---. child .-> dst -. xfrm .-> xfrm_state #3
  51                                       |---. child .-> NULL
  52
  53    Bundles are cached at xrfm_policy struct (field ->bundles).
  54
  55
  56    Resolution of xrfm_tmpl
  57    -----------------------
  58    Template contains:
  59    1. ->mode            Mode: transport or tunnel
  60    2. ->id.proto        Protocol: AH/ESP/IPCOMP
  61    3. ->id.daddr        Remote tunnel endpoint, ignored for transport mode.
  62       Q: allow to resolve security gateway?
  63    4. ->id.spi          If not zero, static SPI.
  64    5. ->saddr           Local tunnel endpoint, ignored for transport mode.
  65    6. ->algos           List of allowed algos. Plain bitmask now.
  66       Q: ealgos, aalgos, calgos. What a mess...
  67    7. ->share           Sharing mode.
  68       Q: how to implement private sharing mode? To add struct sock* to
  69       flow id?
  70
  71    Having this template we search through SAD searching for entries
  72    with appropriate mode/proto/algo, permitted by selector.
  73    If no appropriate entry found, it is requested from key manager.
  74
  75    PROBLEMS:
  76    Q: How to find all the bundles referring to a physical path for
  77       PMTU discovery? Seems, dst should contain list of all parents...
  78       and enter to infinite locking hierarchy disaster.
  79       No! It is easier, we will not search for them, let them find us.
  80       We add genid to each dst plus pointer to genid of raw IP route,
  81       pmtu disc will update pmtu on raw IP route and increase its genid.
  82       dst_check() will see this for top level and trigger resyncing
  83       metrics. Plus, it will be made via sk->sk_dst_cache. Solved.
  84  */
  85
  86 /* Full description of state of transformer. */
  87 struct xfrm_state
  88 {
  89         /* Note: bydst is re-used during gc */
  90         struct list_head        bydst;
  91         struct list_head        byspi;
  92
  93         atomic_t                refcnt;
  94         spinlock_t              lock;
  95
  96         struct xfrm_id          id;
  97         struct xfrm_selector    sel;
  98
  99         /* Key manger bits */
 100         struct {
 101                 u8              state;
 102                 u8              dying;
 103                 u32             seq;
 104         } km;
 105
 106         /* Parameters of this state. */
 107         struct {
 108                 u32             reqid;
 109                 u8              mode;
 110                 u8              replay_window;
 111                 u8              aalgo, ealgo, calgo;
 112                 u8              flags;
 113                 u16             family;
 114                 xfrm_address_t  saddr;
 115                 int             header_len;
 116                 int             trailer_len;
 117         } props;
 118
 119         struct xfrm_lifetime_cfg lft;
 120
 121         /* Data for transformer */
 122         struct xfrm_algo        *aalg;
 123         struct xfrm_algo        *ealg;
 124         struct xfrm_algo        *calg;
 125
 126         /* Data for encapsulator */
 127         struct xfrm_encap_tmpl  *encap;
 128
 129         /* IPComp needs an IPIP tunnel for handling uncompressed packets */
 130         struct xfrm_state       *tunnel;
 131
 132         /* If a tunnel, number of users + 1 */
 133         atomic_t                tunnel_users;
 134
 135         /* State for replay detection */
 136         struct xfrm_replay_state replay;
 137
 138         /* Statistics */
 139         struct xfrm_stats       stats;
 140
 141         struct xfrm_lifetime_cur curlft;
 142         struct timer_list       timer;
 143
 144         /* Reference to data common to all the instances of this
 145          * transformer. */
 146         struct xfrm_type        *type;
 147
 148         /* Security context */
 149         struct xfrm_sec_ctx     *security;
 150
 151         /* Private data of this transformer, format is opaque,
 152          * interpreted by xfrm_type methods. */
 153         void                    *data;
 154 };
 155
 156 enum {
 157         XFRM_STATE_VOID,
 158         XFRM_STATE_ACQ,
 159         XFRM_STATE_VALID,
 160         XFRM_STATE_ERROR,
 161         XFRM_STATE_EXPIRED,
 162         XFRM_STATE_DEAD
 163 };
 164
 165 /* callback structure passed from either netlink or pfkey */
 166 struct km_event
 167 {
 168         union {
 169                 u32 hard;
 170                 u32 proto;
 171                 u32 byid;
 172         } data;
 173
 174         u32     seq;
 175         u32     pid;
 176         u32     event;
 177 };
 178
 179 struct xfrm_type;
 180 struct xfrm_dst;
 181 struct xfrm_policy_afinfo {
 182         unsigned short          family;
 183         rwlock_t                lock;
 184         struct xfrm_type_map    *type_map;
 185         struct dst_ops          *dst_ops;
 186         void                    (*garbage_collect)(void);
 187         int                     (*dst_lookup)(struct xfrm_dst **dst, struct flowi *fl);
 188         struct dst_entry        *(*find_bundle)(struct flowi *fl, struct xfrm_policy *policy);
 189         int                     (*bundle_create)(struct xfrm_policy *policy,
 190                                                  struct xfrm_state **xfrm,
 191                                                  int nx,
 192                                                  struct flowi *fl,
 193                                                  struct dst_entry **dst_p);
 194         void                    (*decode_session)(struct sk_buff *skb,
 195                                                   struct flowi *fl);
 196 };
 197
 198 extern int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo);
 199 extern int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo);
 200 extern void km_policy_notify(struct xfrm_policy *xp, int dir, struct km_event *c);
 201 extern void km_state_notify(struct xfrm_state *x, struct km_event *c);
 202
 203 #define XFRM_ACQ_EXPIRES        30
 204
 205 struct xfrm_tmpl;
 206 struct xfrm_state_afinfo {
 207         unsigned short          family;
 208         rwlock_t                lock;
 209         struct list_head        *state_bydst;
 210         struct list_head        *state_byspi;
 211         int                     (*init_flags)(struct xfrm_state *x);
 212         void                    (*init_tempsel)(struct xfrm_state *x, struct flowi *fl,
 213                                                 struct xfrm_tmpl *tmpl,
 214                                                 xfrm_address_t *daddr, xfrm_address_t *saddr);
 215         struct xfrm_state       *(*state_lookup)(xfrm_address_t *daddr, u32 spi, u8 proto);
 216         struct xfrm_state       *(*find_acq)(u8 mode, u32 reqid, u8 proto,
 217                                              xfrm_address_t *daddr, xfrm_address_t *saddr,
 218                                              int create);
 219 };
 220
 221 extern int xfrm_state_register_afinfo(struct xfrm_state_afinfo *afinfo);
 222 extern int xfrm_state_unregister_afinfo(struct xfrm_state_afinfo *afinfo);
 223
 224 extern void xfrm_state_delete_tunnel(struct xfrm_state *x);
 225
 226 struct xfrm_decap_state;
 227 struct xfrm_type
 228 {
 229         char                    *description;
 230         struct module           *owner;
 231         __u8                    proto;
 232
 233         int                     (*init_state)(struct xfrm_state *x);
 234         void                    (*destructor)(struct xfrm_state *);
 235         int                     (*input)(struct xfrm_state *, struct xfrm_decap_state *, struct sk_buff *skb);
 236         int                     (*post_input)(struct xfrm_state *, struct xfrm_decap_state *, struct sk_buff *skb);
 237         int                     (*output)(struct xfrm_state *, struct sk_buff *pskb);
 238         /* Estimate maximal size of result of transformation of a dgram */
 239         u32                     (*get_max_size)(struct xfrm_state *, int size);
 240 };
 241
 242 struct xfrm_type_map {
 243         rwlock_t                lock;
 244         struct xfrm_type        *map[256];
 245 };
 246
 247 extern int xfrm_register_type(struct xfrm_type *type, unsigned short family);
 248 extern int xfrm_unregister_type(struct xfrm_type *type, unsigned short family);
 249 extern struct xfrm_type *xfrm_get_type(u8 proto, unsigned short family);
 250 extern void xfrm_put_type(struct xfrm_type *type);
 251
 252 struct xfrm_tmpl
 253 {
 254 /* id in template is interpreted as:
 255  * daddr - destination of tunnel, may be zero for transport mode.
 256  * spi   - zero to acquire spi. Not zero if spi is static, then
 257  *         daddr must be fixed too.
 258  * proto - AH/ESP/IPCOMP
 259  */
 260         struct xfrm_id          id;
 261
 262 /* Source address of tunnel. Ignored, if it is not a tunnel. */
 263         xfrm_address_t          saddr;
 264
 265         __u32                   reqid;
 266
 267 /* Mode: transport/tunnel */
 268         __u8                    mode;
 269
 270 /* Sharing mode: unique, this session only, this user only etc. */
 271         __u8                    share;
 272
 273 /* May skip this transfomration if no SA is found */
 274         __u8                    optional;
 275
 276 /* Bit mask of algos allowed for acquisition */
 277         __u32                   aalgos;
 278         __u32                   ealgos;
 279         __u32                   calgos;
 280 };
 281
 282 #define XFRM_MAX_DEPTH          4
 283
 284 struct xfrm_policy
 285 {
 286         struct xfrm_policy      *next;
 287         struct list_head        list;
 288
 289         /* This lock only affects elements except for entry. */
 290         rwlock_t                lock;
 291         atomic_t                refcnt;
 292         struct timer_list       timer;
 293
 294         u32                     priority;
 295         u32                     index;
 296         struct xfrm_selector    selector;
 297         struct xfrm_lifetime_cfg lft;
 298         struct xfrm_lifetime_cur curlft;
 299         struct dst_entry       *bundles;
 300         __u16                   family;
 301         __u8                    action;
 302         __u8                    flags;
 303         __u8                    dead;
 304         __u8                    xfrm_nr;
 305         struct xfrm_sec_ctx     *security;
 306         struct xfrm_tmpl        xfrm_vec[XFRM_MAX_DEPTH];
 307 };
 308
 309 #define XFRM_KM_TIMEOUT         30
 310
 311 struct xfrm_mgr
 312 {
 313         struct list_head        list;
 314         char                    *id;
 315         int                     (*notify)(struct xfrm_state *x, struct km_event *c);
 316         int                     (*acquire)(struct xfrm_state *x, struct xfrm_tmpl *, struct xfrm_policy *xp, int dir);
 317         struct xfrm_policy      *(*compile_policy)(u16 family, int opt, u8 *data, int len, int *dir);
 318         int                     (*new_mapping)(struct xfrm_state *x, xfrm_address_t *ipaddr, u16 sport);
 319         int                     (*notify_policy)(struct xfrm_policy *x, int dir, struct km_event *c);
 320 };
 321
 322 extern int xfrm_register_km(struct xfrm_mgr *km);
 323 extern int xfrm_unregister_km(struct xfrm_mgr *km);
 324
 325
 326 extern struct xfrm_policy *xfrm_policy_list[XFRM_POLICY_MAX*2];
 327
 328 static inline void xfrm_pol_hold(struct xfrm_policy *policy)
 329 {
 330         if (likely(policy != NULL))
 331                 atomic_inc(&policy->refcnt);
 332 }
 333
 334 extern void __xfrm_policy_destroy(struct xfrm_policy *policy);
 335
 336 static inline void xfrm_pol_put(struct xfrm_policy *policy)
 337 {
 338         if (atomic_dec_and_test(&policy->refcnt))
 339                 __xfrm_policy_destroy(policy);
 340 }
 341
 342 #define XFRM_DST_HSIZE          1024
 343
 344 static __inline__
 345 unsigned __xfrm4_dst_hash(xfrm_address_t *addr)
 346 {
 347         unsigned h;
 348         h = ntohl(addr->a4);
 349         h = (h ^ (h>>16)) % XFRM_DST_HSIZE;
 350         return h;
 351 }
 352
 353 static __inline__
 354 unsigned __xfrm6_dst_hash(xfrm_address_t *addr)
 355 {
 356         unsigned h;
 357         h = ntohl(addr->a6[2]^addr->a6[3]);
 358         h = (h ^ (h>>16)) % XFRM_DST_HSIZE;
 359         return h;
 360 }
 361
 362 static __inline__
 363 unsigned xfrm_dst_hash(xfrm_address_t *addr, unsigned short family)
 364 {
 365         switch (family) {
 366         case AF_INET:
 367                 return __xfrm4_dst_hash(addr);
 368         case AF_INET6:
 369                 return __xfrm6_dst_hash(addr);
 370         }
 371         return 0;
 372 }
 373
 374 static __inline__
 375 unsigned __xfrm4_spi_hash(xfrm_address_t *addr, u32 spi, u8 proto)
 376 {
 377         unsigned h;
 378         h = ntohl(addr->a4^spi^proto);
 379         h = (h ^ (h>>10) ^ (h>>20)) % XFRM_DST_HSIZE;
 380         return h;
 381 }
 382
 383 static __inline__
 384 unsigned __xfrm6_spi_hash(xfrm_address_t *addr, u32 spi, u8 proto)
 385 {
 386         unsigned h;
 387         h = ntohl(addr->a6[2]^addr->a6[3]^spi^proto);
 388         h = (h ^ (h>>10) ^ (h>>20)) % XFRM_DST_HSIZE;
 389         return h;
 390 }
 391
 392 static __inline__
 393 unsigned xfrm_spi_hash(xfrm_address_t *addr, u32 spi, u8 proto, unsigned short family)
 394 {
 395         switch (family) {
 396         case AF_INET:
 397                 return __xfrm4_spi_hash(addr, spi, proto);
 398         case AF_INET6:
 399                 return __xfrm6_spi_hash(addr, spi, proto);
 400         }
 401         return 0;       /*XXX*/
 402 }
 403
 404 extern void __xfrm_state_destroy(struct xfrm_state *);
 405
 406 static inline void xfrm_state_put(struct xfrm_state *x)
 407 {
 408         if (atomic_dec_and_test(&x->refcnt))
 409                 __xfrm_state_destroy(x);
 410 }
 411
 412 static inline void xfrm_state_hold(struct xfrm_state *x)
 413 {
 414         atomic_inc(&x->refcnt);
 415 }
 416
 417 static __inline__ int addr_match(void *token1, void *token2, int prefixlen)
 418 {
 419         __u32 *a1 = token1;
 420         __u32 *a2 = token2;
 421         int pdw;
 422         int pbi;
 423
 424         pdw = prefixlen >> 5;     /* num of whole __u32 in prefix */
 425         pbi = prefixlen &  0x1f;  /* num of bits in incomplete u32 in prefix */
 426
 427         if (pdw)
 428                 if (memcmp(a1, a2, pdw << 2))
 429                         return 0;
 430
 431         if (pbi) {
 432                 __u32 mask;
 433
 434                 mask = htonl((0xffffffff) << (32 - pbi));
 435
 436                 if ((a1[pdw] ^ a2[pdw]) & mask)
 437                         return 0;
 438         }
 439
 440         return 1;
 441 }
 442
 443 static __inline__
 444 u16 xfrm_flowi_sport(struct flowi *fl)
 445 {
 446         u16 port;
 447         switch(fl->proto) {
 448         case IPPROTO_TCP:
 449         case IPPROTO_UDP:
 450         case IPPROTO_SCTP:
 451                 port = fl->fl_ip_sport;
 452                 break;
 453         case IPPROTO_ICMP:
 454         case IPPROTO_ICMPV6:
 455                 port = htons(fl->fl_icmp_type);
 456                 break;
 457         default:
 458                 port = 0;       /*XXX*/
 459         }
 460         return port;
 461 }
 462
 463 static __inline__
 464 u16 xfrm_flowi_dport(struct flowi *fl)
 465 {
 466         u16 port;
 467         switch(fl->proto) {
 468         case IPPROTO_TCP:
 469         case IPPROTO_UDP:
 470         case IPPROTO_SCTP:
 471                 port = fl->fl_ip_dport;
 472                 break;
 473         case IPPROTO_ICMP:
 474         case IPPROTO_ICMPV6:
 475                 port = htons(fl->fl_icmp_code);
 476                 break;
 477         default:
 478                 port = 0;       /*XXX*/
 479         }
 480         return port;
 481 }
 482
 483 static inline int
 484 __xfrm4_selector_match(struct xfrm_selector *sel, struct flowi *fl)
 485 {
 486         return  addr_match(&fl->fl4_dst, &sel->daddr, sel->prefixlen_d) &&
 487                 addr_match(&fl->fl4_src, &sel->saddr, sel->prefixlen_s) &&
 488                 !((xfrm_flowi_dport(fl) ^ sel->dport) & sel->dport_mask) &&
 489                 !((xfrm_flowi_sport(fl) ^ sel->sport) & sel->sport_mask) &&
 490                 (fl->proto == sel->proto || !sel->proto) &&
 491                 (fl->oif == sel->ifindex || !sel->ifindex);
 492 }
 493
 494 static inline int
 495 __xfrm6_selector_match(struct xfrm_selector *sel, struct flowi *fl)
 496 {
 497         return  addr_match(&fl->fl6_dst, &sel->daddr, sel->prefixlen_d) &&
 498                 addr_match(&fl->fl6_src, &sel->saddr, sel->prefixlen_s) &&
 499                 !((xfrm_flowi_dport(fl) ^ sel->dport) & sel->dport_mask) &&
 500                 !((xfrm_flowi_sport(fl) ^ sel->sport) & sel->sport_mask) &&
 501                 (fl->proto == sel->proto || !sel->proto) &&
 502                 (fl->oif == sel->ifindex || !sel->ifindex);
 503 }
 504
 505 static inline int
 506 xfrm_selector_match(struct xfrm_selector *sel, struct flowi *fl,
 507                     unsigned short family)
 508 {
 509         switch (family) {
 510         case AF_INET:
 511                 return __xfrm4_selector_match(sel, fl);
 512         case AF_INET6:
 513                 return __xfrm6_selector_match(sel, fl);
 514         }
 515         return 0;
 516 }
 517
 518 #ifdef CONFIG_SECURITY_NETWORK_XFRM
 519 /*      If neither has a context --> match
 520  *      Otherwise, both must have a context and the sids, doi, alg must match
 521  */
 522 static inline int xfrm_sec_ctx_match(struct xfrm_sec_ctx *s1, struct xfrm_sec_ctx *s2)
 523 {
 524         return ((!s1 && !s2) ||
 525                 (s1 && s2 &&
 526                  (s1->ctx_sid == s2->ctx_sid) &&
 527                  (s1->ctx_doi == s2->ctx_doi) &&
 528                  (s1->ctx_alg == s2->ctx_alg)));
 529 }
 530 #else
 531 static inline int xfrm_sec_ctx_match(struct xfrm_sec_ctx *s1, struct xfrm_sec_ctx *s2)
 532 {
 533         return 1;
 534 }
 535 #endif
 536
 537 /* A struct encoding bundle of transformations to apply to some set of flow.
 538  *
 539  * dst->child points to the next element of bundle.
 540  * dst->xfrm  points to an instanse of transformer.
 541  *
 542  * Due to unfortunate limitations of current routing cache, which we
 543  * have no time to fix, it mirrors struct rtable and bound to the same
 544  * routing key, including saddr,daddr. However, we can have many of
 545  * bundles differing by session id. All the bundles grow from a parent
 546  * policy rule.
 547  */
 548 struct xfrm_dst
 549 {
 550         union {
 551                 struct xfrm_dst         *next;
 552                 struct dst_entry        dst;
 553                 struct rtable           rt;
 554                 struct rt6_info         rt6;
 555         } u;
 556         struct dst_entry *route;
 557         u32 route_mtu_cached;
 558         u32 child_mtu_cached;
 559         u32 route_cookie;
 560         u32 path_cookie;
 561 };
 562
 563 static inline void xfrm_dst_destroy(struct xfrm_dst *xdst)
 564 {
 565         dst_release(xdst->route);
 566         if (likely(xdst->u.dst.xfrm))
 567                 xfrm_state_put(xdst->u.dst.xfrm);
 568 }
 569
 570 extern void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev);
 571
 572 /* Decapsulation state, used by the input to store data during
 573  * decapsulation procedure, to be used later (during the policy
 574  * check
 575  */
 576 struct xfrm_decap_state {
 577         char    decap_data[20];
 578         __u16   decap_type;
 579 };
 580
 581 struct sec_decap_state {
 582         struct xfrm_state       *xvec;
 583         struct xfrm_decap_state decap;
 584 };
 585
 586 struct sec_path
 587 {
 588         atomic_t                refcnt;
 589         int                     len;
 590         struct sec_decap_state  x[XFRM_MAX_DEPTH];
 591 };
 592
 593 static inline struct sec_path *
 594 secpath_get(struct sec_path *sp)
 595 {
 596         if (sp)
 597                 atomic_inc(&sp->refcnt);
 598         return sp;
 599 }
 600
 601 extern void __secpath_destroy(struct sec_path *sp);
 602
 603 static inline void
 604 secpath_put(struct sec_path *sp)
 605 {
 606         if (sp && atomic_dec_and_test(&sp->refcnt))
 607                 __secpath_destroy(sp);
 608 }
 609
 610 extern struct sec_path *secpath_dup(struct sec_path *src);
 611
 612 static inline void
 613 secpath_reset(struct sk_buff *skb)
 614 {
 615 #ifdef CONFIG_XFRM
 616         secpath_put(skb->sp);
 617         skb->sp = NULL;
 618 #endif
 619 }
 620
 621 static inline int
 622 __xfrm4_state_addr_cmp(struct xfrm_tmpl *tmpl, struct xfrm_state *x)
 623 {
 624         return  (tmpl->saddr.a4 &&
 625                  tmpl->saddr.a4 != x->props.saddr.a4);
 626 }
 627
 628 static inline int
 629 __xfrm6_state_addr_cmp(struct xfrm_tmpl *tmpl, struct xfrm_state *x)
 630 {
 631         return  (!ipv6_addr_any((struct in6_addr*)&tmpl->saddr) &&
 632                  ipv6_addr_cmp((struct in6_addr *)&tmpl->saddr, (struct in6_addr*)&x->props.saddr));
 633 }
 634
 635 static inline int
 636 xfrm_state_addr_cmp(struct xfrm_tmpl *tmpl, struct xfrm_state *x, unsigned short family)
 637 {
 638         switch (family) {
 639         case AF_INET:
 640                 return __xfrm4_state_addr_cmp(tmpl, x);
 641         case AF_INET6:
 642                 return __xfrm6_state_addr_cmp(tmpl, x);
 643         }
 644         return !0;
 645 }
 646
 647 #ifdef CONFIG_XFRM
 648
 649 extern int __xfrm_policy_check(struct sock *, int dir, struct sk_buff *skb, unsigned short family);
 650
 651 static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
 652 {
 653         if (sk && sk->sk_policy[XFRM_POLICY_IN])
 654                 return __xfrm_policy_check(sk, dir, skb, family);
 655
 656         return  (!xfrm_policy_list[dir] && !skb->sp) ||
 657                 (skb->dst->flags & DST_NOPOLICY) ||
 658                 __xfrm_policy_check(sk, dir, skb, family);
 659 }
 660
 661 static inline int xfrm4_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
 662 {
 663         return xfrm_policy_check(sk, dir, skb, AF_INET);
 664 }
 665
 666 static inline int xfrm6_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
 667 {
 668         return xfrm_policy_check(sk, dir, skb, AF_INET6);
 669 }
 670
 671 extern int xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, unsigned short family);
 672 extern int __xfrm_route_forward(struct sk_buff *skb, unsigned short family);
 673
 674 static inline int xfrm_route_forward(struct sk_buff *skb, unsigned short family)
 675 {
 676         return  !xfrm_policy_list[XFRM_POLICY_OUT] ||
 677                 (skb->dst->flags & DST_NOXFRM) ||
 678                 __xfrm_route_forward(skb, family);
 679 }
 680
 681 static inline int xfrm4_route_forward(struct sk_buff *skb)
 682 {
 683         return xfrm_route_forward(skb, AF_INET);
 684 }
 685
 686 static inline int xfrm6_route_forward(struct sk_buff *skb)
 687 {
 688         return xfrm_route_forward(skb, AF_INET6);
 689 }
 690
 691 extern int __xfrm_sk_clone_policy(struct sock *sk);
 692
 693 static inline int xfrm_sk_clone_policy(struct sock *sk)
 694 {
 695         if (unlikely(sk->sk_policy[0] || sk->sk_policy[1]))
 696                 return __xfrm_sk_clone_policy(sk);
 697         return 0;
 698 }
 699
 700 extern int xfrm_policy_delete(struct xfrm_policy *pol, int dir);
 701
 702 static inline void xfrm_sk_free_policy(struct sock *sk)
 703 {
 704         if (unlikely(sk->sk_policy[0] != NULL)) {
 705                 xfrm_policy_delete(sk->sk_policy[0], XFRM_POLICY_MAX);
 706                 sk->sk_policy[0] = NULL;
 707         }
 708         if (unlikely(sk->sk_policy[1] != NULL)) {
 709                 xfrm_policy_delete(sk->sk_policy[1], XFRM_POLICY_MAX+1);
 710                 sk->sk_policy[1] = NULL;
 711         }
 712 }
 713
 714 #else
 715
 716 static inline void xfrm_sk_free_policy(struct sock *sk) {}
 717 static inline int xfrm_sk_clone_policy(struct sock *sk) { return 0; }
 718 static inline int xfrm6_route_forward(struct sk_buff *skb) { return 1; }
 719 static inline int xfrm4_route_forward(struct sk_buff *skb) { return 1; }
 720 static inline int xfrm6_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
 721 {
 722         return 1;
 723 }
 724 static inline int xfrm4_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
 725 {
 726         return 1;
 727 }
 728 static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
 729 {
 730         return 1;
 731 }
 732 #endif
 733
 734 static __inline__
 735 xfrm_address_t *xfrm_flowi_daddr(struct flowi *fl, unsigned short family)
 736 {
 737         switch (family){
 738         case AF_INET:
 739                 return (xfrm_address_t *)&fl->fl4_dst;
 740         case AF_INET6:
 741                 return (xfrm_address_t *)&fl->fl6_dst;
 742         }
 743         return NULL;
 744 }
 745
 746 static __inline__
 747 xfrm_address_t *xfrm_flowi_saddr(struct flowi *fl, unsigned short family)
 748 {
 749         switch (family){
 750         case AF_INET:
 751                 return (xfrm_address_t *)&fl->fl4_src;
 752         case AF_INET6:
 753                 return (xfrm_address_t *)&fl->fl6_src;
 754         }
 755         return NULL;
 756 }
 757
 758 static __inline__ int
 759 __xfrm4_state_addr_check(struct xfrm_state *x,
 760                          xfrm_address_t *daddr, xfrm_address_t *saddr)
 761 {
 762         if (daddr->a4 == x->id.daddr.a4 &&
 763             (saddr->a4 == x->props.saddr.a4 || !saddr->a4 || !x->props.saddr.a4))
 764                 return 1;
 765         return 0;
 766 }
 767
 768 static __inline__ int
 769 __xfrm6_state_addr_check(struct xfrm_state *x,
 770                          xfrm_address_t *daddr, xfrm_address_t *saddr)
 771 {
 772         if (!ipv6_addr_cmp((struct in6_addr *)daddr, (struct in6_addr *)&x->id.daddr) &&
 773             (!ipv6_addr_cmp((struct in6_addr *)saddr, (struct in6_addr *)&x->props.saddr)||
 774              ipv6_addr_any((struct in6_addr *)saddr) ||
 775              ipv6_addr_any((struct in6_addr *)&x->props.saddr)))
 776                 return 1;
 777         return 0;
 778 }
 779
 780 static __inline__ int
 781 xfrm_state_addr_check(struct xfrm_state *x,
 782                       xfrm_address_t *daddr, xfrm_address_t *saddr,
 783                       unsigned short family)
 784 {
 785         switch (family) {
 786         case AF_INET:
 787                 return __xfrm4_state_addr_check(x, daddr, saddr);
 788         case AF_INET6:
 789                 return __xfrm6_state_addr_check(x, daddr, saddr);
 790         }
 791         return 0;
 792 }
 793
 794 static inline int xfrm_state_kern(struct xfrm_state *x)
 795 {
 796         return atomic_read(&x->tunnel_users);
 797 }
 798
 799 /*
 800  * xfrm algorithm information
 801  */
 802 struct xfrm_algo_auth_info {
 803         u16 icv_truncbits;
 804         u16 icv_fullbits;
 805 };
 806
 807 struct xfrm_algo_encr_info {
 808         u16 blockbits;
 809         u16 defkeybits;
 810 };
 811
 812 struct xfrm_algo_comp_info {
 813         u16 threshold;
 814 };
 815
 816 struct xfrm_algo_desc {
 817         char *name;
 818         u8 available:1;
 819         union {
 820                 struct xfrm_algo_auth_info auth;
 821                 struct xfrm_algo_encr_info encr;
 822                 struct xfrm_algo_comp_info comp;
 823         } uinfo;
 824         struct sadb_alg desc;
 825 };
 826
 827 /* XFRM tunnel handlers.  */
 828 struct xfrm_tunnel {
 829         int (*handler)(struct sk_buff *skb);
 830         void (*err_handler)(struct sk_buff *skb, __u32 info);
 831 };
 832
 833 struct xfrm6_tunnel {
 834         int (*handler)(struct sk_buff **pskb);
 835         void (*err_handler)(struct sk_buff *skb, struct inet6_skb_parm *opt,
 836                             int type, int code, int offset, __u32 info);
 837 };
 838
 839 extern void xfrm_init(void);
 840 extern void xfrm4_init(void);
 841 extern void xfrm6_init(void);
 842 extern void xfrm6_fini(void);
 843 extern void xfrm_state_init(void);
 844 extern void xfrm4_state_init(void);
 845 extern void xfrm6_state_init(void);
 846 extern void xfrm6_state_fini(void);
 847
 848 extern int xfrm_state_walk(u8 proto, int (*func)(struct xfrm_state *, int, void*), void *);
 849 extern struct xfrm_state *xfrm_state_alloc(void);
 850 extern struct xfrm_state *xfrm_state_find(xfrm_address_t *daddr, xfrm_address_t *saddr,
 851                                           struct flowi *fl, struct xfrm_tmpl *tmpl,
 852                                           struct xfrm_policy *pol, int *err,
 853                                           unsigned short family);
 854 extern int xfrm_state_check_expire(struct xfrm_state *x);
 855 extern void xfrm_state_insert(struct xfrm_state *x);
 856 extern int xfrm_state_add(struct xfrm_state *x);
 857 extern int xfrm_state_update(struct xfrm_state *x);
 858 extern struct xfrm_state *xfrm_state_lookup(xfrm_address_t *daddr, u32 spi, u8 proto, unsigned short family);
 859 extern struct xfrm_state *xfrm_find_acq_byseq(u32 seq);
 860 extern int xfrm_state_delete(struct xfrm_state *x);
 861 extern void xfrm_state_flush(u8 proto);
 862 extern int xfrm_replay_check(struct xfrm_state *x, u32 seq);
 863 extern void xfrm_replay_advance(struct xfrm_state *x, u32 seq);
 864 extern int xfrm_state_check(struct xfrm_state *x, struct sk_buff *skb);
 865 extern int xfrm_state_mtu(struct xfrm_state *x, int mtu);
 866 extern int xfrm_init_state(struct xfrm_state *x);
 867 extern int xfrm4_rcv(struct sk_buff *skb);
 868 extern int xfrm4_output(struct sk_buff *skb);
 869 extern int xfrm4_output_finish(struct sk_buff *skb);
 870 extern int xfrm4_tunnel_register(struct xfrm_tunnel *handler);
 871 extern int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler);
 872 extern int xfrm6_rcv_spi(struct sk_buff **pskb, u32 spi);
 873 extern int xfrm6_rcv(struct sk_buff **pskb);
 874 extern int xfrm6_tunnel_register(struct xfrm6_tunnel *handler);
 875 extern int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler);
 876 extern u32 xfrm6_tunnel_alloc_spi(xfrm_address_t *saddr);
 877 extern void xfrm6_tunnel_free_spi(xfrm_address_t *saddr);
 878 extern u32 xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr);
 879 extern int xfrm6_output(struct sk_buff *skb);
 880
 881 #ifdef CONFIG_XFRM
 882 extern int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type);
 883 extern int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen);
 884 extern int xfrm_dst_lookup(struct xfrm_dst **dst, struct flowi *fl, unsigned short family);
 885 #else
 886 static inline int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen)
 887 {
 888         return -ENOPROTOOPT;
 889 }
 890
 891 static inline int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type)
 892 {
 893         /* should not happen */
 894         kfree_skb(skb);
 895         return 0;
 896 }
 897 static inline int xfrm_dst_lookup(struct xfrm_dst **dst, struct flowi *fl, unsigned short family)
 898 {
 899         return -EINVAL;
 900 }
 901 #endif
 902
 903 struct xfrm_policy *xfrm_policy_alloc(gfp_t gfp);
 904 extern int xfrm_policy_walk(int (*func)(struct xfrm_policy *, int, int, void*), void *);
 905 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl);
 906 struct xfrm_policy *xfrm_policy_bysel_ctx(int dir, struct xfrm_selector *sel,
 907                                           struct xfrm_sec_ctx *ctx, int delete);
 908 struct xfrm_policy *xfrm_policy_byid(int dir, u32 id, int delete);
 909 void xfrm_policy_flush(void);
 910 u32 xfrm_get_acqseq(void);
 911 void xfrm_alloc_spi(struct xfrm_state *x, u32 minspi, u32 maxspi);
 912 struct xfrm_state * xfrm_find_acq(u8 mode, u32 reqid, u8 proto,
 913                                   xfrm_address_t *daddr, xfrm_address_t *saddr,
 914                                   int create, unsigned short family);
 915 extern void xfrm_policy_flush(void);
 916 extern int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol);
 917 extern int xfrm_flush_bundles(void);
 918 extern void xfrm_flush_all_bundles(void);
 919 extern int xfrm_bundle_ok(struct xfrm_dst *xdst, struct flowi *fl, int family);
 920 extern void xfrm_init_pmtu(struct dst_entry *dst);
 921
 922 extern wait_queue_head_t km_waitq;
 923 extern int km_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr, u16 sport);
 924 extern void km_policy_expired(struct xfrm_policy *pol, int dir, int hard);
 925
 926 extern void xfrm_input_init(void);
 927 extern int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, u32 *spi, u32 *seq);
 928
 929 extern void xfrm_probe_algs(void);
 930 extern int xfrm_count_auth_supported(void);
 931 extern int xfrm_count_enc_supported(void);
 932 extern struct xfrm_algo_desc *xfrm_aalg_get_byidx(unsigned int idx);
 933 extern struct xfrm_algo_desc *xfrm_ealg_get_byidx(unsigned int idx);
 934 extern struct xfrm_algo_desc *xfrm_aalg_get_byid(int alg_id);
 935 extern struct xfrm_algo_desc *xfrm_ealg_get_byid(int alg_id);
 936 extern struct xfrm_algo_desc *xfrm_calg_get_byid(int alg_id);
 937 extern struct xfrm_algo_desc *xfrm_aalg_get_byname(char *name, int probe);
 938 extern struct xfrm_algo_desc *xfrm_ealg_get_byname(char *name, int probe);
 939 extern struct xfrm_algo_desc *xfrm_calg_get_byname(char *name, int probe);
 940
 941 struct crypto_tfm;
 942 typedef void (icv_update_fn_t)(struct crypto_tfm *, struct scatterlist *, unsigned int);
 943
 944 extern void skb_icv_walk(const struct sk_buff *skb, struct crypto_tfm *tfm,
 945                          int offset, int len, icv_update_fn_t icv_update);
 946
 947 static inline int xfrm_addr_cmp(xfrm_address_t *a, xfrm_address_t *b,
 948                                 int family)
 949 {
 950         switch (family) {
 951         default:
 952         case AF_INET:
 953                 return a->a4 - b->a4;
 954         case AF_INET6:
 955                 return ipv6_addr_cmp((struct in6_addr *)a,
 956                                      (struct in6_addr *)b);
 957         }
 958 }
 959
 960 static inline int xfrm_policy_id2dir(u32 index)
 961 {
 962         return index & 7;
 963 }
 964
 965 #endif  /* _NET_XFRM_H */