include/net/xfrm.h

   1 #ifndef _NET_XFRM_H
   2 #define _NET_XFRM_H
   3
   4 #include <linux/xfrm.h>
   5 #include <linux/spinlock.h>
   6 #include <linux/list.h>
   7 #include <linux/skbuff.h>
   8 #include <linux/netdevice.h>
   9 #include <linux/crypto.h>
  10 #include <linux/pfkeyv2.h>
  11 #include <linux/in6.h>
  12
  13 #include <net/sock.h>
  14 #include <net/dst.h>
  15 #include <net/route.h>
  16 #include <net/ipv6.h>
  17 #include <net/ip6_fib.h>
  18
  19 #define XFRM_ALIGN8(len)        (((len) + 7) & ~7)
  20
  21 extern struct semaphore xfrm_cfg_sem;
  22
  23 /* Organization of SPD aka "XFRM rules"
  24    ------------------------------------
  25
  26    Basic objects:
  27    - policy rule, struct xfrm_policy (=SPD entry)
  28    - bundle of transformations, struct dst_entry == struct xfrm_dst (=SA bundle)
  29    - instance of a transformer, struct xfrm_state (=SA)
  30    - template to clone xfrm_state, struct xfrm_tmpl
  31
  32    SPD is plain linear list of xfrm_policy rules, ordered by priority.
  33    (To be compatible with existing pfkeyv2 implementations,
  34    many rules with priority of 0x7fffffff are allowed to exist and
  35    such rules are ordered in an unpredictable way, thanks to bsd folks.)
  36
  37    Lookup is plain linear search until the first match with selector.
  38
  39    If "action" is "block", then we prohibit the flow, otherwise:
  40    if "xfrms_nr" is zero, the flow passes untransformed. Otherwise,
  41    policy entry has list of up to XFRM_MAX_DEPTH transformations,
  42    described by templates xfrm_tmpl. Each template is resolved
  43    to a complete xfrm_state (see below) and we pack bundle of transformations
  44    to a dst_entry returned to requestor.
  45
  46    dst -. xfrm  .-> xfrm_state #1
  47     |---. child .-> dst -. xfrm .-> xfrm_state #2
  48                      |---. child .-> dst -. xfrm .-> xfrm_state #3
  49                                       |---. child .-> NULL
  50
  51    Bundles are cached at xrfm_policy struct (field ->bundles).
  52
  53
  54    Resolution of xrfm_tmpl
  55    -----------------------
  56    Template contains:
  57    1. ->mode            Mode: transport or tunnel
  58    2. ->id.proto        Protocol: AH/ESP/IPCOMP
  59    3. ->id.daddr        Remote tunnel endpoint, ignored for transport mode.
  60       Q: allow to resolve security gateway?
  61    4. ->id.spi          If not zero, static SPI.
  62    5. ->saddr           Local tunnel endpoint, ignored for transport mode.
  63    6. ->algos           List of allowed algos. Plain bitmask now.
  64       Q: ealgos, aalgos, calgos. What a mess...
  65    7. ->share           Sharing mode.
  66       Q: how to implement private sharing mode? To add struct sock* to
  67       flow id?
  68
  69    Having this template we search through SAD searching for entries
  70    with appropriate mode/proto/algo, permitted by selector.
  71    If no appropriate entry found, it is requested from key manager.
  72
  73    PROBLEMS:
  74    Q: How to find all the bundles referring to a physical path for
  75       PMTU discovery? Seems, dst should contain list of all parents...
  76       and enter to infinite locking hierarchy disaster.
  77       No! It is easier, we will not search for them, let them find us.
  78       We add genid to each dst plus pointer to genid of raw IP route,
  79       pmtu disc will update pmtu on raw IP route and increase its genid.
  80       dst_check() will see this for top level and trigger resyncing
  81       metrics. Plus, it will be made via sk->sk_dst_cache. Solved.
  82  */
  83
  84 /* Full description of state of transformer. */
  85 struct xfrm_state
  86 {
  87         /* Note: bydst is re-used during gc */
  88         struct list_head        bydst;
  89         struct list_head        byspi;
  90
  91         atomic_t                refcnt;
  92         spinlock_t              lock;
  93
  94         struct xfrm_id          id;
  95         struct xfrm_selector    sel;
  96
  97         /* Key manger bits */
  98         struct {
  99                 u8              state;
 100                 u8              dying;
 101                 u32             seq;
 102         } km;
 103
 104         /* Parameters of this state. */
 105         struct {
 106                 u32             reqid;
 107                 u8              mode;
 108                 u8              replay_window;
 109                 u8              aalgo, ealgo, calgo;
 110                 u8              flags;
 111                 u16             family;
 112                 xfrm_address_t  saddr;
 113                 int             header_len;
 114                 int             trailer_len;
 115         } props;
 116
 117         struct xfrm_lifetime_cfg lft;
 118
 119         /* Data for transformer */
 120         struct xfrm_algo        *aalg;
 121         struct xfrm_algo        *ealg;
 122         struct xfrm_algo        *calg;
 123
 124         /* Data for encapsulator */
 125         struct xfrm_encap_tmpl  *encap;
 126
 127         /* IPComp needs an IPIP tunnel for handling uncompressed packets */
 128         struct xfrm_state       *tunnel;
 129
 130         /* If a tunnel, number of users + 1 */
 131         atomic_t                tunnel_users;
 132
 133         /* State for replay detection */
 134         struct xfrm_replay_state replay;
 135
 136         /* Statistics */
 137         struct xfrm_stats       stats;
 138
 139         struct xfrm_lifetime_cur curlft;
 140         struct timer_list       timer;
 141
 142         /* Reference to data common to all the instances of this
 143          * transformer. */
 144         struct xfrm_type        *type;
 145
 146         /* Private data of this transformer, format is opaque,
 147          * interpreted by xfrm_type methods. */
 148         void                    *data;
 149 };
 150
 151 enum {
 152         XFRM_STATE_VOID,
 153         XFRM_STATE_ACQ,
 154         XFRM_STATE_VALID,
 155         XFRM_STATE_ERROR,
 156         XFRM_STATE_EXPIRED,
 157         XFRM_STATE_DEAD
 158 };
 159
 160 struct xfrm_type;
 161 struct xfrm_dst;
 162 struct xfrm_policy_afinfo {
 163         unsigned short          family;
 164         rwlock_t                lock;
 165         struct xfrm_type_map    *type_map;
 166         struct dst_ops          *dst_ops;
 167         void                    (*garbage_collect)(void);
 168         int                     (*dst_lookup)(struct xfrm_dst **dst, struct flowi *fl);
 169         struct dst_entry        *(*find_bundle)(struct flowi *fl, struct xfrm_policy *policy);
 170         int                     (*bundle_create)(struct xfrm_policy *policy,
 171                                                  struct xfrm_state **xfrm,
 172                                                  int nx,
 173                                                  struct flowi *fl,
 174                                                  struct dst_entry **dst_p);
 175         void                    (*decode_session)(struct sk_buff *skb,
 176                                                   struct flowi *fl);
 177 };
 178
 179 extern int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo);
 180 extern int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo);
 181
 182 #define XFRM_ACQ_EXPIRES        30
 183
 184 struct xfrm_tmpl;
 185 struct xfrm_state_afinfo {
 186         unsigned short          family;
 187         rwlock_t                lock;
 188         struct list_head        *state_bydst;
 189         struct list_head        *state_byspi;
 190         void                    (*init_tempsel)(struct xfrm_state *x, struct flowi *fl,
 191                                                 struct xfrm_tmpl *tmpl,
 192                                                 xfrm_address_t *daddr, xfrm_address_t *saddr);
 193         struct xfrm_state       *(*state_lookup)(xfrm_address_t *daddr, u32 spi, u8 proto);
 194         struct xfrm_state       *(*find_acq)(u8 mode, u32 reqid, u8 proto,
 195                                              xfrm_address_t *daddr, xfrm_address_t *saddr,
 196                                              int create);
 197 };
 198
 199 extern int xfrm_state_register_afinfo(struct xfrm_state_afinfo *afinfo);
 200 extern int xfrm_state_unregister_afinfo(struct xfrm_state_afinfo *afinfo);
 201
 202 extern void xfrm_state_delete_tunnel(struct xfrm_state *x);
 203
 204 struct xfrm_decap_state;
 205 struct xfrm_type
 206 {
 207         char                    *description;
 208         struct module           *owner;
 209         __u8                    proto;
 210
 211         int                     (*init_state)(struct xfrm_state *x, void *args);
 212         void                    (*destructor)(struct xfrm_state *);
 213         int                     (*input)(struct xfrm_state *, struct xfrm_decap_state *, struct sk_buff *skb);
 214         int                     (*post_input)(struct xfrm_state *, struct xfrm_decap_state *, struct sk_buff *skb);
 215         int                     (*output)(struct xfrm_state *, struct sk_buff *pskb);
 216         /* Estimate maximal size of result of transformation of a dgram */
 217         u32                     (*get_max_size)(struct xfrm_state *, int size);
 218 };
 219
 220 struct xfrm_type_map {
 221         rwlock_t                lock;
 222         struct xfrm_type        *map[256];
 223 };
 224
 225 extern int xfrm_register_type(struct xfrm_type *type, unsigned short family);
 226 extern int xfrm_unregister_type(struct xfrm_type *type, unsigned short family);
 227 extern struct xfrm_type *xfrm_get_type(u8 proto, unsigned short family);
 228 extern void xfrm_put_type(struct xfrm_type *type);
 229
 230 struct xfrm_tmpl
 231 {
 232 /* id in template is interpreted as:
 233  * daddr - destination of tunnel, may be zero for transport mode.
 234  * spi   - zero to acquire spi. Not zero if spi is static, then
 235  *         daddr must be fixed too.
 236  * proto - AH/ESP/IPCOMP
 237  */
 238         struct xfrm_id          id;
 239
 240 /* Source address of tunnel. Ignored, if it is not a tunnel. */
 241         xfrm_address_t          saddr;
 242
 243         __u32                   reqid;
 244
 245 /* Mode: transport/tunnel */
 246         __u8                    mode;
 247
 248 /* Sharing mode: unique, this session only, this user only etc. */
 249         __u8                    share;
 250
 251 /* May skip this transfomration if no SA is found */
 252         __u8                    optional;
 253
 254 /* Bit mask of algos allowed for acquisition */
 255         __u32                   aalgos;
 256         __u32                   ealgos;
 257         __u32                   calgos;
 258 };
 259
 260 #define XFRM_MAX_DEPTH          4
 261
 262 struct xfrm_policy
 263 {
 264         struct xfrm_policy      *next;
 265         struct list_head        list;
 266
 267         /* This lock only affects elements except for entry. */
 268         rwlock_t                lock;
 269         atomic_t                refcnt;
 270         struct timer_list       timer;
 271
 272         u32                     priority;
 273         u32                     index;
 274         struct xfrm_selector    selector;
 275         struct xfrm_lifetime_cfg lft;
 276         struct xfrm_lifetime_cur curlft;
 277         struct dst_entry       *bundles;
 278         __u16                   family;
 279         __u8                    action;
 280         __u8                    flags;
 281         __u8                    dead;
 282         __u8                    xfrm_nr;
 283         struct xfrm_tmpl        xfrm_vec[XFRM_MAX_DEPTH];
 284 };
 285
 286 #define XFRM_KM_TIMEOUT         30
 287
 288 struct xfrm_mgr
 289 {
 290         struct list_head        list;
 291         char                    *id;
 292         int                     (*notify)(struct xfrm_state *x, int event);
 293         int                     (*acquire)(struct xfrm_state *x, struct xfrm_tmpl *, struct xfrm_policy *xp, int dir);
 294         struct xfrm_policy      *(*compile_policy)(u16 family, int opt, u8 *data, int len, int *dir);
 295         int                     (*new_mapping)(struct xfrm_state *x, xfrm_address_t *ipaddr, u16 sport);
 296         int                     (*notify_policy)(struct xfrm_policy *x, int dir, int event);
 297 };
 298
 299 extern int xfrm_register_km(struct xfrm_mgr *km);
 300 extern int xfrm_unregister_km(struct xfrm_mgr *km);
 301
 302
 303 extern struct xfrm_policy *xfrm_policy_list[XFRM_POLICY_MAX*2];
 304
 305 static inline void xfrm_pol_hold(struct xfrm_policy *policy)
 306 {
 307         if (likely(policy != NULL))
 308                 atomic_inc(&policy->refcnt);
 309 }
 310
 311 extern void __xfrm_policy_destroy(struct xfrm_policy *policy);
 312
 313 static inline void xfrm_pol_put(struct xfrm_policy *policy)
 314 {
 315         if (atomic_dec_and_test(&policy->refcnt))
 316                 __xfrm_policy_destroy(policy);
 317 }
 318
 319 #define XFRM_DST_HSIZE          1024
 320
 321 static __inline__
 322 unsigned __xfrm4_dst_hash(xfrm_address_t *addr)
 323 {
 324         unsigned h;
 325         h = ntohl(addr->a4);
 326         h = (h ^ (h>>16)) % XFRM_DST_HSIZE;
 327         return h;
 328 }
 329
 330 static __inline__
 331 unsigned __xfrm6_dst_hash(xfrm_address_t *addr)
 332 {
 333         unsigned h;
 334         h = ntohl(addr->a6[2]^addr->a6[3]);
 335         h = (h ^ (h>>16)) % XFRM_DST_HSIZE;
 336         return h;
 337 }
 338
 339 static __inline__
 340 unsigned xfrm_dst_hash(xfrm_address_t *addr, unsigned short family)
 341 {
 342         switch (family) {
 343         case AF_INET:
 344                 return __xfrm4_dst_hash(addr);
 345         case AF_INET6:
 346                 return __xfrm6_dst_hash(addr);
 347         }
 348         return 0;
 349 }
 350
 351 static __inline__
 352 unsigned __xfrm4_spi_hash(xfrm_address_t *addr, u32 spi, u8 proto)
 353 {
 354         unsigned h;
 355         h = ntohl(addr->a4^spi^proto);
 356         h = (h ^ (h>>10) ^ (h>>20)) % XFRM_DST_HSIZE;
 357         return h;
 358 }
 359
 360 static __inline__
 361 unsigned __xfrm6_spi_hash(xfrm_address_t *addr, u32 spi, u8 proto)
 362 {
 363         unsigned h;
 364         h = ntohl(addr->a6[2]^addr->a6[3]^spi^proto);
 365         h = (h ^ (h>>10) ^ (h>>20)) % XFRM_DST_HSIZE;
 366         return h;
 367 }
 368
 369 static __inline__
 370 unsigned xfrm_spi_hash(xfrm_address_t *addr, u32 spi, u8 proto, unsigned short family)
 371 {
 372         switch (family) {
 373         case AF_INET:
 374                 return __xfrm4_spi_hash(addr, spi, proto);
 375         case AF_INET6:
 376                 return __xfrm6_spi_hash(addr, spi, proto);
 377         }
 378         return 0;       /*XXX*/
 379 }
 380
 381 extern void __xfrm_state_destroy(struct xfrm_state *);
 382
 383 static inline void xfrm_state_put(struct xfrm_state *x)
 384 {
 385         if (atomic_dec_and_test(&x->refcnt))
 386                 __xfrm_state_destroy(x);
 387 }
 388
 389 static inline void xfrm_state_hold(struct xfrm_state *x)
 390 {
 391         atomic_inc(&x->refcnt);
 392 }
 393
 394 static __inline__ int addr_match(void *token1, void *token2, int prefixlen)
 395 {
 396         __u32 *a1 = token1;
 397         __u32 *a2 = token2;
 398         int pdw;
 399         int pbi;
 400
 401         pdw = prefixlen >> 5;     /* num of whole __u32 in prefix */
 402         pbi = prefixlen &  0x1f;  /* num of bits in incomplete u32 in prefix */
 403
 404         if (pdw)
 405                 if (memcmp(a1, a2, pdw << 2))
 406                         return 0;
 407
 408         if (pbi) {
 409                 __u32 mask;
 410
 411                 mask = htonl((0xffffffff) << (32 - pbi));
 412
 413                 if ((a1[pdw] ^ a2[pdw]) & mask)
 414                         return 0;
 415         }
 416
 417         return 1;
 418 }
 419
 420 static __inline__
 421 u16 xfrm_flowi_sport(struct flowi *fl)
 422 {
 423         u16 port;
 424         switch(fl->proto) {
 425         case IPPROTO_TCP:
 426         case IPPROTO_UDP:
 427         case IPPROTO_SCTP:
 428                 port = fl->fl_ip_sport;
 429                 break;
 430         case IPPROTO_ICMP:
 431         case IPPROTO_ICMPV6:
 432                 port = htons(fl->fl_icmp_type);
 433                 break;
 434         default:
 435                 port = 0;       /*XXX*/
 436         }
 437         return port;
 438 }
 439
 440 static __inline__
 441 u16 xfrm_flowi_dport(struct flowi *fl)
 442 {
 443         u16 port;
 444         switch(fl->proto) {
 445         case IPPROTO_TCP:
 446         case IPPROTO_UDP:
 447         case IPPROTO_SCTP:
 448                 port = fl->fl_ip_dport;
 449                 break;
 450         case IPPROTO_ICMP:
 451         case IPPROTO_ICMPV6:
 452                 port = htons(fl->fl_icmp_code);
 453                 break;
 454         default:
 455                 port = 0;       /*XXX*/
 456         }
 457         return port;
 458 }
 459
 460 static inline int
 461 __xfrm4_selector_match(struct xfrm_selector *sel, struct flowi *fl)
 462 {
 463         return  addr_match(&fl->fl4_dst, &sel->daddr, sel->prefixlen_d) &&
 464                 addr_match(&fl->fl4_src, &sel->saddr, sel->prefixlen_s) &&
 465                 !((xfrm_flowi_dport(fl) ^ sel->dport) & sel->dport_mask) &&
 466                 !((xfrm_flowi_sport(fl) ^ sel->sport) & sel->sport_mask) &&
 467                 (fl->proto == sel->proto || !sel->proto) &&
 468                 (fl->oif == sel->ifindex || !sel->ifindex);
 469 }
 470
 471 static inline int
 472 __xfrm6_selector_match(struct xfrm_selector *sel, struct flowi *fl)
 473 {
 474         return  addr_match(&fl->fl6_dst, &sel->daddr, sel->prefixlen_d) &&
 475                 addr_match(&fl->fl6_src, &sel->saddr, sel->prefixlen_s) &&
 476                 !((xfrm_flowi_dport(fl) ^ sel->dport) & sel->dport_mask) &&
 477                 !((xfrm_flowi_sport(fl) ^ sel->sport) & sel->sport_mask) &&
 478                 (fl->proto == sel->proto || !sel->proto) &&
 479                 (fl->oif == sel->ifindex || !sel->ifindex);
 480 }
 481
 482 static inline int
 483 xfrm_selector_match(struct xfrm_selector *sel, struct flowi *fl,
 484                     unsigned short family)
 485 {
 486         switch (family) {
 487         case AF_INET:
 488                 return __xfrm4_selector_match(sel, fl);
 489         case AF_INET6:
 490                 return __xfrm6_selector_match(sel, fl);
 491         }
 492         return 0;
 493 }
 494
 495 /* A struct encoding bundle of transformations to apply to some set of flow.
 496  *
 497  * dst->child points to the next element of bundle.
 498  * dst->xfrm  points to an instanse of transformer.
 499  *
 500  * Due to unfortunate limitations of current routing cache, which we
 501  * have no time to fix, it mirrors struct rtable and bound to the same
 502  * routing key, including saddr,daddr. However, we can have many of
 503  * bundles differing by session id. All the bundles grow from a parent
 504  * policy rule.
 505  */
 506 struct xfrm_dst
 507 {
 508         union {
 509                 struct xfrm_dst         *next;
 510                 struct dst_entry        dst;
 511                 struct rtable           rt;
 512                 struct rt6_info         rt6;
 513         } u;
 514         struct dst_entry *route;
 515         u32 route_mtu_cached;
 516         u32 child_mtu_cached;
 517 };
 518
 519 /* Decapsulation state, used by the input to store data during
 520  * decapsulation procedure, to be used later (during the policy
 521  * check
 522  */
 523 struct xfrm_decap_state {
 524         char    decap_data[20];
 525         __u16   decap_type;
 526 };
 527
 528 struct sec_decap_state {
 529         struct xfrm_state       *xvec;
 530         struct xfrm_decap_state decap;
 531 };
 532
 533 struct sec_path
 534 {
 535         atomic_t                refcnt;
 536         int                     len;
 537         struct sec_decap_state  x[XFRM_MAX_DEPTH];
 538 };
 539
 540 static inline struct sec_path *
 541 secpath_get(struct sec_path *sp)
 542 {
 543         if (sp)
 544                 atomic_inc(&sp->refcnt);
 545         return sp;
 546 }
 547
 548 extern void __secpath_destroy(struct sec_path *sp);
 549
 550 static inline void
 551 secpath_put(struct sec_path *sp)
 552 {
 553         if (sp && atomic_dec_and_test(&sp->refcnt))
 554                 __secpath_destroy(sp);
 555 }
 556
 557 extern struct sec_path *secpath_dup(struct sec_path *src);
 558
 559 static inline void
 560 secpath_reset(struct sk_buff *skb)
 561 {
 562 #ifdef CONFIG_XFRM
 563         secpath_put(skb->sp);
 564         skb->sp = NULL;
 565 #endif
 566 }
 567
 568 static inline int
 569 __xfrm4_state_addr_cmp(struct xfrm_tmpl *tmpl, struct xfrm_state *x)
 570 {
 571         return  (tmpl->saddr.a4 &&
 572                  tmpl->saddr.a4 != x->props.saddr.a4);
 573 }
 574
 575 static inline int
 576 __xfrm6_state_addr_cmp(struct xfrm_tmpl *tmpl, struct xfrm_state *x)
 577 {
 578         return  (!ipv6_addr_any((struct in6_addr*)&tmpl->saddr) &&
 579                  ipv6_addr_cmp((struct in6_addr *)&tmpl->saddr, (struct in6_addr*)&x->props.saddr));
 580 }
 581
 582 static inline int
 583 xfrm_state_addr_cmp(struct xfrm_tmpl *tmpl, struct xfrm_state *x, unsigned short family)
 584 {
 585         switch (family) {
 586         case AF_INET:
 587                 return __xfrm4_state_addr_cmp(tmpl, x);
 588         case AF_INET6:
 589                 return __xfrm6_state_addr_cmp(tmpl, x);
 590         }
 591         return !0;
 592 }
 593
 594 #ifdef CONFIG_XFRM
 595
 596 extern int __xfrm_policy_check(struct sock *, int dir, struct sk_buff *skb, unsigned short family);
 597
 598 static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
 599 {
 600         if (sk && sk->sk_policy[XFRM_POLICY_IN])
 601                 return __xfrm_policy_check(sk, dir, skb, family);
 602
 603         return  (!xfrm_policy_list[dir] && !skb->sp) ||
 604                 (skb->dst->flags & DST_NOPOLICY) ||
 605                 __xfrm_policy_check(sk, dir, skb, family);
 606 }
 607
 608 static inline int xfrm4_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
 609 {
 610         return xfrm_policy_check(sk, dir, skb, AF_INET);
 611 }
 612
 613 static inline int xfrm6_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
 614 {
 615         return xfrm_policy_check(sk, dir, skb, AF_INET6);
 616 }
 617
 618
 619 extern int __xfrm_route_forward(struct sk_buff *skb, unsigned short family);
 620
 621 static inline int xfrm_route_forward(struct sk_buff *skb, unsigned short family)
 622 {
 623         return  !xfrm_policy_list[XFRM_POLICY_OUT] ||
 624                 (skb->dst->flags & DST_NOXFRM) ||
 625                 __xfrm_route_forward(skb, family);
 626 }
 627
 628 static inline int xfrm4_route_forward(struct sk_buff *skb)
 629 {
 630         return xfrm_route_forward(skb, AF_INET);
 631 }
 632
 633 static inline int xfrm6_route_forward(struct sk_buff *skb)
 634 {
 635         return xfrm_route_forward(skb, AF_INET6);
 636 }
 637
 638 extern int __xfrm_sk_clone_policy(struct sock *sk);
 639
 640 static inline int xfrm_sk_clone_policy(struct sock *sk)
 641 {
 642         if (unlikely(sk->sk_policy[0] || sk->sk_policy[1]))
 643                 return __xfrm_sk_clone_policy(sk);
 644         return 0;
 645 }
 646
 647 extern void xfrm_policy_delete(struct xfrm_policy *pol, int dir);
 648
 649 static inline void xfrm_sk_free_policy(struct sock *sk)
 650 {
 651         if (unlikely(sk->sk_policy[0] != NULL)) {
 652                 xfrm_policy_delete(sk->sk_policy[0], XFRM_POLICY_MAX);
 653                 sk->sk_policy[0] = NULL;
 654         }
 655         if (unlikely(sk->sk_policy[1] != NULL)) {
 656                 xfrm_policy_delete(sk->sk_policy[1], XFRM_POLICY_MAX+1);
 657                 sk->sk_policy[1] = NULL;
 658         }
 659 }
 660
 661 #else
 662
 663 static inline void xfrm_sk_free_policy(struct sock *sk) {}
 664 static inline int xfrm_sk_clone_policy(struct sock *sk) { return 0; }
 665 static inline int xfrm6_route_forward(struct sk_buff *skb) { return 1; }
 666 static inline int xfrm4_route_forward(struct sk_buff *skb) { return 1; }
 667 static inline int xfrm6_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
 668 {
 669         return 1;
 670 }
 671 static inline int xfrm4_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
 672 {
 673         return 1;
 674 }
 675 static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
 676 {
 677         return 1;
 678 }
 679 #endif
 680
 681 static __inline__
 682 xfrm_address_t *xfrm_flowi_daddr(struct flowi *fl, unsigned short family)
 683 {
 684         switch (family){
 685         case AF_INET:
 686                 return (xfrm_address_t *)&fl->fl4_dst;
 687         case AF_INET6:
 688                 return (xfrm_address_t *)&fl->fl6_dst;
 689         }
 690         return NULL;
 691 }
 692
 693 static __inline__
 694 xfrm_address_t *xfrm_flowi_saddr(struct flowi *fl, unsigned short family)
 695 {
 696         switch (family){
 697         case AF_INET:
 698                 return (xfrm_address_t *)&fl->fl4_src;
 699         case AF_INET6:
 700                 return (xfrm_address_t *)&fl->fl6_src;
 701         }
 702         return NULL;
 703 }
 704
 705 static __inline__ int
 706 __xfrm4_state_addr_check(struct xfrm_state *x,
 707                          xfrm_address_t *daddr, xfrm_address_t *saddr)
 708 {
 709         if (daddr->a4 == x->id.daddr.a4 &&
 710             (saddr->a4 == x->props.saddr.a4 || !saddr->a4 || !x->props.saddr.a4))
 711                 return 1;
 712         return 0;
 713 }
 714
 715 static __inline__ int
 716 __xfrm6_state_addr_check(struct xfrm_state *x,
 717                          xfrm_address_t *daddr, xfrm_address_t *saddr)
 718 {
 719         if (!ipv6_addr_cmp((struct in6_addr *)daddr, (struct in6_addr *)&x->id.daddr) &&
 720             (!ipv6_addr_cmp((struct in6_addr *)saddr, (struct in6_addr *)&x->props.saddr)||
 721              ipv6_addr_any((struct in6_addr *)saddr) ||
 722              ipv6_addr_any((struct in6_addr *)&x->props.saddr)))
 723                 return 1;
 724         return 0;
 725 }
 726
 727 static __inline__ int
 728 xfrm_state_addr_check(struct xfrm_state *x,
 729                       xfrm_address_t *daddr, xfrm_address_t *saddr,
 730                       unsigned short family)
 731 {
 732         switch (family) {
 733         case AF_INET:
 734                 return __xfrm4_state_addr_check(x, daddr, saddr);
 735         case AF_INET6:
 736                 return __xfrm6_state_addr_check(x, daddr, saddr);
 737         }
 738         return 0;
 739 }
 740
 741 static inline int xfrm_state_kern(struct xfrm_state *x)
 742 {
 743         return atomic_read(&x->tunnel_users);
 744 }
 745
 746 /*
 747  * xfrm algorithm information
 748  */
 749 struct xfrm_algo_auth_info {
 750         u16 icv_truncbits;
 751         u16 icv_fullbits;
 752 };
 753
 754 struct xfrm_algo_encr_info {
 755         u16 blockbits;
 756         u16 defkeybits;
 757 };
 758
 759 struct xfrm_algo_comp_info {
 760         u16 threshold;
 761 };
 762
 763 struct xfrm_algo_desc {
 764         char *name;
 765         u8 available:1;
 766         union {
 767                 struct xfrm_algo_auth_info auth;
 768                 struct xfrm_algo_encr_info encr;
 769                 struct xfrm_algo_comp_info comp;
 770         } uinfo;
 771         struct sadb_alg desc;
 772 };
 773
 774 /* XFRM tunnel handlers.  */
 775 struct xfrm_tunnel {
 776         int (*handler)(struct sk_buff *skb);
 777         void (*err_handler)(struct sk_buff *skb, void *info);
 778 };
 779
 780 struct xfrm6_tunnel {
 781         int (*handler)(struct sk_buff **pskb, unsigned int *nhoffp);
 782         void (*err_handler)(struct sk_buff *skb, struct inet6_skb_parm *opt,
 783                             int type, int code, int offset, __u32 info);
 784 };
 785
 786 extern void xfrm_init(void);
 787 extern void xfrm4_init(void);
 788 extern void xfrm6_init(void);
 789 extern void xfrm6_fini(void);
 790 extern void xfrm_state_init(void);
 791 extern void xfrm4_state_init(void);
 792 extern void xfrm4_state_fini(void);
 793 extern void xfrm6_state_init(void);
 794 extern void xfrm6_state_fini(void);
 795
 796 extern int xfrm_state_walk(u8 proto, int (*func)(struct xfrm_state *, int, void*), void *);
 797 extern struct xfrm_state *xfrm_state_alloc(void);
 798 extern struct xfrm_state *xfrm_state_find(xfrm_address_t *daddr, xfrm_address_t *saddr,
 799                                           struct flowi *fl, struct xfrm_tmpl *tmpl,
 800                                           struct xfrm_policy *pol, int *err,
 801                                           unsigned short family);
 802 extern int xfrm_state_check_expire(struct xfrm_state *x);
 803 extern void xfrm_state_insert(struct xfrm_state *x);
 804 extern int xfrm_state_add(struct xfrm_state *x);
 805 extern int xfrm_state_update(struct xfrm_state *x);
 806 extern struct xfrm_state *xfrm_state_lookup(xfrm_address_t *daddr, u32 spi, u8 proto, unsigned short family);
 807 extern struct xfrm_state *xfrm_find_acq_byseq(u32 seq);
 808 extern void xfrm_state_delete(struct xfrm_state *x);
 809 extern void xfrm_state_flush(u8 proto);
 810 extern int xfrm_replay_check(struct xfrm_state *x, u32 seq);
 811 extern void xfrm_replay_advance(struct xfrm_state *x, u32 seq);
 812 extern int xfrm_state_check(struct xfrm_state *x, struct sk_buff *skb);
 813 extern int xfrm_state_mtu(struct xfrm_state *x, int mtu);
 814 extern int xfrm4_rcv(struct sk_buff *skb);
 815 extern int xfrm4_output(struct sk_buff *skb);
 816 extern int xfrm4_tunnel_register(struct xfrm_tunnel *handler);
 817 extern int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler);
 818 extern int xfrm6_rcv_spi(struct sk_buff **pskb, unsigned int *nhoffp, u32 spi);
 819 extern int xfrm6_rcv(struct sk_buff **pskb, unsigned int *nhoffp);
 820 extern int xfrm6_tunnel_register(struct xfrm6_tunnel *handler);
 821 extern int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler);
 822 extern u32 xfrm6_tunnel_alloc_spi(xfrm_address_t *saddr);
 823 extern void xfrm6_tunnel_free_spi(xfrm_address_t *saddr);
 824 extern u32 xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr);
 825 extern int xfrm6_output(struct sk_buff *skb);
 826
 827 #ifdef CONFIG_XFRM
 828 extern int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type);
 829 extern int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen);
 830 extern int xfrm_dst_lookup(struct xfrm_dst **dst, struct flowi *fl, unsigned short family);
 831 #else
 832 static inline int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen)
 833 {
 834         return -ENOPROTOOPT;
 835 }
 836
 837 static inline int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type)
 838 {
 839         /* should not happen */
 840         kfree_skb(skb);
 841         return 0;
 842 }
 843 static inline int xfrm_dst_lookup(struct xfrm_dst **dst, struct flowi *fl, unsigned short family)
 844 {
 845         return -EINVAL;
 846 }
 847 #endif
 848
 849 struct xfrm_policy *xfrm_policy_alloc(int gfp);
 850 extern int xfrm_policy_walk(int (*func)(struct xfrm_policy *, int, int, void*), void *);
 851 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl);
 852 struct xfrm_policy *xfrm_policy_bysel(int dir, struct xfrm_selector *sel,
 853                                       int delete);
 854 struct xfrm_policy *xfrm_policy_byid(int dir, u32 id, int delete);
 855 void xfrm_policy_flush(void);
 856 u32 xfrm_get_acqseq(void);
 857 void xfrm_alloc_spi(struct xfrm_state *x, u32 minspi, u32 maxspi);
 858 struct xfrm_state * xfrm_find_acq(u8 mode, u32 reqid, u8 proto,
 859                                   xfrm_address_t *daddr, xfrm_address_t *saddr,
 860                                   int create, unsigned short family);
 861 extern void xfrm_policy_flush(void);
 862 extern int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol);
 863 extern int xfrm_flush_bundles(void);
 864 extern int xfrm_bundle_ok(struct xfrm_dst *xdst, struct flowi *fl, int family);
 865 extern void xfrm_init_pmtu(struct dst_entry *dst);
 866
 867 extern wait_queue_head_t km_waitq;
 868 extern int km_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr, u16 sport);
 869 extern void km_policy_expired(struct xfrm_policy *pol, int dir, int hard);
 870
 871 extern void xfrm_input_init(void);
 872 extern int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, u32 *spi, u32 *seq);
 873
 874 extern void xfrm_probe_algs(void);
 875 extern int xfrm_count_auth_supported(void);
 876 extern int xfrm_count_enc_supported(void);
 877 extern struct xfrm_algo_desc *xfrm_aalg_get_byidx(unsigned int idx);
 878 extern struct xfrm_algo_desc *xfrm_ealg_get_byidx(unsigned int idx);
 879 extern struct xfrm_algo_desc *xfrm_aalg_get_byid(int alg_id);
 880 extern struct xfrm_algo_desc *xfrm_ealg_get_byid(int alg_id);
 881 extern struct xfrm_algo_desc *xfrm_calg_get_byid(int alg_id);
 882 extern struct xfrm_algo_desc *xfrm_aalg_get_byname(char *name, int probe);
 883 extern struct xfrm_algo_desc *xfrm_ealg_get_byname(char *name, int probe);
 884 extern struct xfrm_algo_desc *xfrm_calg_get_byname(char *name, int probe);
 885
 886 struct crypto_tfm;
 887 typedef void (icv_update_fn_t)(struct crypto_tfm *, struct scatterlist *, unsigned int);
 888
 889 extern void skb_icv_walk(const struct sk_buff *skb, struct crypto_tfm *tfm,
 890                          int offset, int len, icv_update_fn_t icv_update);
 891
 892 static inline int xfrm_addr_cmp(xfrm_address_t *a, xfrm_address_t *b,
 893                                 int family)
 894 {
 895         switch (family) {
 896         default:
 897         case AF_INET:
 898                 return a->a4 - b->a4;
 899         case AF_INET6:
 900                 return ipv6_addr_cmp((struct in6_addr *)a,
 901                                      (struct in6_addr *)b);
 902         }
 903 }
 904
 905 #endif  /* _NET_XFRM_H */