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         atomic_dec(&x->refcnt);
 409 }
 410
 411 static inline void xfrm_state_put(struct xfrm_state *x)
 412 {
 413         if (atomic_dec_and_test(&x->refcnt))
 414                 __xfrm_state_destroy(x);
 415 }
 416
 417 static inline void xfrm_state_hold(struct xfrm_state *x)
 418 {
 419         atomic_inc(&x->refcnt);
 420 }
 421
 422 static __inline__ int addr_match(void *token1, void *token2, int prefixlen)
 423 {
 424         __u32 *a1 = token1;
 425         __u32 *a2 = token2;
 426         int pdw;
 427         int pbi;
 428
 429         pdw = prefixlen >> 5;     /* num of whole __u32 in prefix */
 430         pbi = prefixlen &  0x1f;  /* num of bits in incomplete u32 in prefix */
 431
 432         if (pdw)
 433                 if (memcmp(a1, a2, pdw << 2))
 434                         return 0;
 435
 436         if (pbi) {
 437                 __u32 mask;
 438
 439                 mask = htonl((0xffffffff) << (32 - pbi));
 440
 441                 if ((a1[pdw] ^ a2[pdw]) & mask)
 442                         return 0;
 443         }
 444
 445         return 1;
 446 }
 447
 448 static __inline__
 449 u16 xfrm_flowi_sport(struct flowi *fl)
 450 {
 451         u16 port;
 452         switch(fl->proto) {
 453         case IPPROTO_TCP:
 454         case IPPROTO_UDP:
 455         case IPPROTO_SCTP:
 456                 port = fl->fl_ip_sport;
 457                 break;
 458         case IPPROTO_ICMP:
 459         case IPPROTO_ICMPV6:
 460                 port = htons(fl->fl_icmp_type);
 461                 break;
 462         default:
 463                 port = 0;       /*XXX*/
 464         }
 465         return port;
 466 }
 467
 468 static __inline__
 469 u16 xfrm_flowi_dport(struct flowi *fl)
 470 {
 471         u16 port;
 472         switch(fl->proto) {
 473         case IPPROTO_TCP:
 474         case IPPROTO_UDP:
 475         case IPPROTO_SCTP:
 476                 port = fl->fl_ip_dport;
 477                 break;
 478         case IPPROTO_ICMP:
 479         case IPPROTO_ICMPV6:
 480                 port = htons(fl->fl_icmp_code);
 481                 break;
 482         default:
 483                 port = 0;       /*XXX*/
 484         }
 485         return port;
 486 }
 487
 488 static inline int
 489 __xfrm4_selector_match(struct xfrm_selector *sel, struct flowi *fl)
 490 {
 491         return  addr_match(&fl->fl4_dst, &sel->daddr, sel->prefixlen_d) &&
 492                 addr_match(&fl->fl4_src, &sel->saddr, sel->prefixlen_s) &&
 493                 !((xfrm_flowi_dport(fl) ^ sel->dport) & sel->dport_mask) &&
 494                 !((xfrm_flowi_sport(fl) ^ sel->sport) & sel->sport_mask) &&
 495                 (fl->proto == sel->proto || !sel->proto) &&
 496                 (fl->oif == sel->ifindex || !sel->ifindex);
 497 }
 498
 499 static inline int
 500 __xfrm6_selector_match(struct xfrm_selector *sel, struct flowi *fl)
 501 {
 502         return  addr_match(&fl->fl6_dst, &sel->daddr, sel->prefixlen_d) &&
 503                 addr_match(&fl->fl6_src, &sel->saddr, sel->prefixlen_s) &&
 504                 !((xfrm_flowi_dport(fl) ^ sel->dport) & sel->dport_mask) &&
 505                 !((xfrm_flowi_sport(fl) ^ sel->sport) & sel->sport_mask) &&
 506                 (fl->proto == sel->proto || !sel->proto) &&
 507                 (fl->oif == sel->ifindex || !sel->ifindex);
 508 }
 509
 510 static inline int
 511 xfrm_selector_match(struct xfrm_selector *sel, struct flowi *fl,
 512                     unsigned short family)
 513 {
 514         switch (family) {
 515         case AF_INET:
 516                 return __xfrm4_selector_match(sel, fl);
 517         case AF_INET6:
 518                 return __xfrm6_selector_match(sel, fl);
 519         }
 520         return 0;
 521 }
 522
 523 #ifdef CONFIG_SECURITY_NETWORK_XFRM
 524 /*      If neither has a context --> match
 525  *      Otherwise, both must have a context and the sids, doi, alg must match
 526  */
 527 static inline int xfrm_sec_ctx_match(struct xfrm_sec_ctx *s1, struct xfrm_sec_ctx *s2)
 528 {
 529         return ((!s1 && !s2) ||
 530                 (s1 && s2 &&
 531                  (s1->ctx_sid == s2->ctx_sid) &&
 532                  (s1->ctx_doi == s2->ctx_doi) &&
 533                  (s1->ctx_alg == s2->ctx_alg)));
 534 }
 535 #else
 536 static inline int xfrm_sec_ctx_match(struct xfrm_sec_ctx *s1, struct xfrm_sec_ctx *s2)
 537 {
 538         return 1;
 539 }
 540 #endif
 541
 542 /* A struct encoding bundle of transformations to apply to some set of flow.
 543  *
 544  * dst->child points to the next element of bundle.
 545  * dst->xfrm  points to an instanse of transformer.
 546  *
 547  * Due to unfortunate limitations of current routing cache, which we
 548  * have no time to fix, it mirrors struct rtable and bound to the same
 549  * routing key, including saddr,daddr. However, we can have many of
 550  * bundles differing by session id. All the bundles grow from a parent
 551  * policy rule.
 552  */
 553 struct xfrm_dst
 554 {
 555         union {
 556                 struct xfrm_dst         *next;
 557                 struct dst_entry        dst;
 558                 struct rtable           rt;
 559                 struct rt6_info         rt6;
 560         } u;
 561         struct dst_entry *route;
 562         u32 route_mtu_cached;
 563         u32 child_mtu_cached;
 564         u32 route_cookie;
 565         u32 path_cookie;
 566 };
 567
 568 static inline void xfrm_dst_destroy(struct xfrm_dst *xdst)
 569 {
 570         dst_release(xdst->route);
 571         if (likely(xdst->u.dst.xfrm))
 572                 xfrm_state_put(xdst->u.dst.xfrm);
 573 }
 574
 575 extern void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev);
 576
 577 /* Decapsulation state, used by the input to store data during
 578  * decapsulation procedure, to be used later (during the policy
 579  * check
 580  */
 581 struct xfrm_decap_state {
 582         char    decap_data[20];
 583         __u16   decap_type;
 584 };
 585
 586 struct sec_decap_state {
 587         struct xfrm_state       *xvec;
 588         struct xfrm_decap_state decap;
 589 };
 590
 591 struct sec_path
 592 {
 593         atomic_t                refcnt;
 594         int                     len;
 595         struct sec_decap_state  x[XFRM_MAX_DEPTH];
 596 };
 597
 598 static inline struct sec_path *
 599 secpath_get(struct sec_path *sp)
 600 {
 601         if (sp)
 602                 atomic_inc(&sp->refcnt);
 603         return sp;
 604 }
 605
 606 extern void __secpath_destroy(struct sec_path *sp);
 607
 608 static inline void
 609 secpath_put(struct sec_path *sp)
 610 {
 611         if (sp && atomic_dec_and_test(&sp->refcnt))
 612                 __secpath_destroy(sp);
 613 }
 614
 615 extern struct sec_path *secpath_dup(struct sec_path *src);
 616
 617 static inline void
 618 secpath_reset(struct sk_buff *skb)
 619 {
 620 #ifdef CONFIG_XFRM
 621         secpath_put(skb->sp);
 622         skb->sp = NULL;
 623 #endif
 624 }
 625
 626 static inline int
 627 __xfrm4_state_addr_cmp(struct xfrm_tmpl *tmpl, struct xfrm_state *x)
 628 {
 629         return  (tmpl->saddr.a4 &&
 630                  tmpl->saddr.a4 != x->props.saddr.a4);
 631 }
 632
 633 static inline int
 634 __xfrm6_state_addr_cmp(struct xfrm_tmpl *tmpl, struct xfrm_state *x)
 635 {
 636         return  (!ipv6_addr_any((struct in6_addr*)&tmpl->saddr) &&
 637                  ipv6_addr_cmp((struct in6_addr *)&tmpl->saddr, (struct in6_addr*)&x->props.saddr));
 638 }
 639
 640 static inline int
 641 xfrm_state_addr_cmp(struct xfrm_tmpl *tmpl, struct xfrm_state *x, unsigned short family)
 642 {
 643         switch (family) {
 644         case AF_INET:
 645                 return __xfrm4_state_addr_cmp(tmpl, x);
 646         case AF_INET6:
 647                 return __xfrm6_state_addr_cmp(tmpl, x);
 648         }
 649         return !0;
 650 }
 651
 652 #ifdef CONFIG_XFRM
 653
 654 extern int __xfrm_policy_check(struct sock *, int dir, struct sk_buff *skb, unsigned short family);
 655
 656 static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
 657 {
 658         if (sk && sk->sk_policy[XFRM_POLICY_IN])
 659                 return __xfrm_policy_check(sk, dir, skb, family);
 660
 661         return  (!xfrm_policy_list[dir] && !skb->sp) ||
 662                 (skb->dst->flags & DST_NOPOLICY) ||
 663                 __xfrm_policy_check(sk, dir, skb, family);
 664 }
 665
 666 static inline int xfrm4_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
 667 {
 668         return xfrm_policy_check(sk, dir, skb, AF_INET);
 669 }
 670
 671 static inline int xfrm6_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
 672 {
 673         return xfrm_policy_check(sk, dir, skb, AF_INET6);
 674 }
 675
 676 extern int xfrm_decode_session(struct sk_buff *skb, struct flowi *fl, unsigned short family);
 677 extern int __xfrm_route_forward(struct sk_buff *skb, unsigned short family);
 678
 679 static inline int xfrm_route_forward(struct sk_buff *skb, unsigned short family)
 680 {
 681         return  !xfrm_policy_list[XFRM_POLICY_OUT] ||
 682                 (skb->dst->flags & DST_NOXFRM) ||
 683                 __xfrm_route_forward(skb, family);
 684 }
 685
 686 static inline int xfrm4_route_forward(struct sk_buff *skb)
 687 {
 688         return xfrm_route_forward(skb, AF_INET);
 689 }
 690
 691 static inline int xfrm6_route_forward(struct sk_buff *skb)
 692 {
 693         return xfrm_route_forward(skb, AF_INET6);
 694 }
 695
 696 extern int __xfrm_sk_clone_policy(struct sock *sk);
 697
 698 static inline int xfrm_sk_clone_policy(struct sock *sk)
 699 {
 700         if (unlikely(sk->sk_policy[0] || sk->sk_policy[1]))
 701                 return __xfrm_sk_clone_policy(sk);
 702         return 0;
 703 }
 704
 705 extern int xfrm_policy_delete(struct xfrm_policy *pol, int dir);
 706
 707 static inline void xfrm_sk_free_policy(struct sock *sk)
 708 {
 709         if (unlikely(sk->sk_policy[0] != NULL)) {
 710                 xfrm_policy_delete(sk->sk_policy[0], XFRM_POLICY_MAX);
 711                 sk->sk_policy[0] = NULL;
 712         }
 713         if (unlikely(sk->sk_policy[1] != NULL)) {
 714                 xfrm_policy_delete(sk->sk_policy[1], XFRM_POLICY_MAX+1);
 715                 sk->sk_policy[1] = NULL;
 716         }
 717 }
 718
 719 #else
 720
 721 static inline void xfrm_sk_free_policy(struct sock *sk) {}
 722 static inline int xfrm_sk_clone_policy(struct sock *sk) { return 0; }
 723 static inline int xfrm6_route_forward(struct sk_buff *skb) { return 1; }
 724 static inline int xfrm4_route_forward(struct sk_buff *skb) { return 1; }
 725 static inline int xfrm6_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
 726 {
 727         return 1;
 728 }
 729 static inline int xfrm4_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
 730 {
 731         return 1;
 732 }
 733 static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
 734 {
 735         return 1;
 736 }
 737 #endif
 738
 739 static __inline__
 740 xfrm_address_t *xfrm_flowi_daddr(struct flowi *fl, unsigned short family)
 741 {
 742         switch (family){
 743         case AF_INET:
 744                 return (xfrm_address_t *)&fl->fl4_dst;
 745         case AF_INET6:
 746                 return (xfrm_address_t *)&fl->fl6_dst;
 747         }
 748         return NULL;
 749 }
 750
 751 static __inline__
 752 xfrm_address_t *xfrm_flowi_saddr(struct flowi *fl, unsigned short family)
 753 {
 754         switch (family){
 755         case AF_INET:
 756                 return (xfrm_address_t *)&fl->fl4_src;
 757         case AF_INET6:
 758                 return (xfrm_address_t *)&fl->fl6_src;
 759         }
 760         return NULL;
 761 }
 762
 763 static __inline__ int
 764 __xfrm4_state_addr_check(struct xfrm_state *x,
 765                          xfrm_address_t *daddr, xfrm_address_t *saddr)
 766 {
 767         if (daddr->a4 == x->id.daddr.a4 &&
 768             (saddr->a4 == x->props.saddr.a4 || !saddr->a4 || !x->props.saddr.a4))
 769                 return 1;
 770         return 0;
 771 }
 772
 773 static __inline__ int
 774 __xfrm6_state_addr_check(struct xfrm_state *x,
 775                          xfrm_address_t *daddr, xfrm_address_t *saddr)
 776 {
 777         if (!ipv6_addr_cmp((struct in6_addr *)daddr, (struct in6_addr *)&x->id.daddr) &&
 778             (!ipv6_addr_cmp((struct in6_addr *)saddr, (struct in6_addr *)&x->props.saddr)||
 779              ipv6_addr_any((struct in6_addr *)saddr) ||
 780              ipv6_addr_any((struct in6_addr *)&x->props.saddr)))
 781                 return 1;
 782         return 0;
 783 }
 784
 785 static __inline__ int
 786 xfrm_state_addr_check(struct xfrm_state *x,
 787                       xfrm_address_t *daddr, xfrm_address_t *saddr,
 788                       unsigned short family)
 789 {
 790         switch (family) {
 791         case AF_INET:
 792                 return __xfrm4_state_addr_check(x, daddr, saddr);
 793         case AF_INET6:
 794                 return __xfrm6_state_addr_check(x, daddr, saddr);
 795         }
 796         return 0;
 797 }
 798
 799 static inline int xfrm_state_kern(struct xfrm_state *x)
 800 {
 801         return atomic_read(&x->tunnel_users);
 802 }
 803
 804 /*
 805  * xfrm algorithm information
 806  */
 807 struct xfrm_algo_auth_info {
 808         u16 icv_truncbits;
 809         u16 icv_fullbits;
 810 };
 811
 812 struct xfrm_algo_encr_info {
 813         u16 blockbits;
 814         u16 defkeybits;
 815 };
 816
 817 struct xfrm_algo_comp_info {
 818         u16 threshold;
 819 };
 820
 821 struct xfrm_algo_desc {
 822         char *name;
 823         u8 available:1;
 824         union {
 825                 struct xfrm_algo_auth_info auth;
 826                 struct xfrm_algo_encr_info encr;
 827                 struct xfrm_algo_comp_info comp;
 828         } uinfo;
 829         struct sadb_alg desc;
 830 };
 831
 832 /* XFRM tunnel handlers.  */
 833 struct xfrm_tunnel {
 834         int (*handler)(struct sk_buff *skb);
 835         void (*err_handler)(struct sk_buff *skb, __u32 info);
 836 };
 837
 838 struct xfrm6_tunnel {
 839         int (*handler)(struct sk_buff **pskb);
 840         void (*err_handler)(struct sk_buff *skb, struct inet6_skb_parm *opt,
 841                             int type, int code, int offset, __u32 info);
 842 };
 843
 844 extern void xfrm_init(void);
 845 extern void xfrm4_init(void);
 846 extern void xfrm6_init(void);
 847 extern void xfrm6_fini(void);
 848 extern void xfrm_state_init(void);
 849 extern void xfrm4_state_init(void);
 850 extern void xfrm6_state_init(void);
 851 extern void xfrm6_state_fini(void);
 852
 853 extern int xfrm_state_walk(u8 proto, int (*func)(struct xfrm_state *, int, void*), void *);
 854 extern struct xfrm_state *xfrm_state_alloc(void);
 855 extern struct xfrm_state *xfrm_state_find(xfrm_address_t *daddr, xfrm_address_t *saddr,
 856                                           struct flowi *fl, struct xfrm_tmpl *tmpl,
 857                                           struct xfrm_policy *pol, int *err,
 858                                           unsigned short family);
 859 extern int xfrm_state_check_expire(struct xfrm_state *x);
 860 extern void xfrm_state_insert(struct xfrm_state *x);
 861 extern int xfrm_state_add(struct xfrm_state *x);
 862 extern int xfrm_state_update(struct xfrm_state *x);
 863 extern struct xfrm_state *xfrm_state_lookup(xfrm_address_t *daddr, u32 spi, u8 proto, unsigned short family);
 864 extern struct xfrm_state *xfrm_find_acq_byseq(u32 seq);
 865 extern int xfrm_state_delete(struct xfrm_state *x);
 866 extern void xfrm_state_flush(u8 proto);
 867 extern int xfrm_replay_check(struct xfrm_state *x, u32 seq);
 868 extern void xfrm_replay_advance(struct xfrm_state *x, u32 seq);
 869 extern int xfrm_state_check(struct xfrm_state *x, struct sk_buff *skb);
 870 extern int xfrm_state_mtu(struct xfrm_state *x, int mtu);
 871 extern int xfrm_init_state(struct xfrm_state *x);
 872 extern int xfrm4_rcv(struct sk_buff *skb);
 873 extern int xfrm4_output(struct sk_buff *skb);
 874 extern int xfrm4_tunnel_register(struct xfrm_tunnel *handler);
 875 extern int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler);
 876 extern int xfrm6_rcv_spi(struct sk_buff **pskb, u32 spi);
 877 extern int xfrm6_rcv(struct sk_buff **pskb);
 878 extern int xfrm6_tunnel_register(struct xfrm6_tunnel *handler);
 879 extern int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler);
 880 extern u32 xfrm6_tunnel_alloc_spi(xfrm_address_t *saddr);
 881 extern void xfrm6_tunnel_free_spi(xfrm_address_t *saddr);
 882 extern u32 xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr);
 883 extern int xfrm6_output(struct sk_buff *skb);
 884
 885 #ifdef CONFIG_XFRM
 886 extern int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type);
 887 extern int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen);
 888 extern int xfrm_dst_lookup(struct xfrm_dst **dst, struct flowi *fl, unsigned short family);
 889 #else
 890 static inline int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen)
 891 {
 892         return -ENOPROTOOPT;
 893 }
 894
 895 static inline int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type)
 896 {
 897         /* should not happen */
 898         kfree_skb(skb);
 899         return 0;
 900 }
 901 static inline int xfrm_dst_lookup(struct xfrm_dst **dst, struct flowi *fl, unsigned short family)
 902 {
 903         return -EINVAL;
 904 }
 905 #endif
 906
 907 struct xfrm_policy *xfrm_policy_alloc(gfp_t gfp);
 908 extern int xfrm_policy_walk(int (*func)(struct xfrm_policy *, int, int, void*), void *);
 909 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl);
 910 struct xfrm_policy *xfrm_policy_bysel_ctx(int dir, struct xfrm_selector *sel,
 911                                           struct xfrm_sec_ctx *ctx, int delete);
 912 struct xfrm_policy *xfrm_policy_byid(int dir, u32 id, int delete);
 913 void xfrm_policy_flush(void);
 914 u32 xfrm_get_acqseq(void);
 915 void xfrm_alloc_spi(struct xfrm_state *x, u32 minspi, u32 maxspi);
 916 struct xfrm_state * xfrm_find_acq(u8 mode, u32 reqid, u8 proto,
 917                                   xfrm_address_t *daddr, xfrm_address_t *saddr,
 918                                   int create, unsigned short family);
 919 extern void xfrm_policy_flush(void);
 920 extern int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol);
 921 extern int xfrm_flush_bundles(void);
 922 extern void xfrm_flush_all_bundles(void);
 923 extern int xfrm_bundle_ok(struct xfrm_dst *xdst, struct flowi *fl, int family);
 924 extern void xfrm_init_pmtu(struct dst_entry *dst);
 925
 926 extern wait_queue_head_t km_waitq;
 927 extern int km_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr, u16 sport);
 928 extern void km_policy_expired(struct xfrm_policy *pol, int dir, int hard);
 929
 930 extern void xfrm_input_init(void);
 931 extern int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, u32 *spi, u32 *seq);
 932
 933 extern void xfrm_probe_algs(void);
 934 extern int xfrm_count_auth_supported(void);
 935 extern int xfrm_count_enc_supported(void);
 936 extern struct xfrm_algo_desc *xfrm_aalg_get_byidx(unsigned int idx);
 937 extern struct xfrm_algo_desc *xfrm_ealg_get_byidx(unsigned int idx);
 938 extern struct xfrm_algo_desc *xfrm_aalg_get_byid(int alg_id);
 939 extern struct xfrm_algo_desc *xfrm_ealg_get_byid(int alg_id);
 940 extern struct xfrm_algo_desc *xfrm_calg_get_byid(int alg_id);
 941 extern struct xfrm_algo_desc *xfrm_aalg_get_byname(char *name, int probe);
 942 extern struct xfrm_algo_desc *xfrm_ealg_get_byname(char *name, int probe);
 943 extern struct xfrm_algo_desc *xfrm_calg_get_byname(char *name, int probe);
 944
 945 struct crypto_tfm;
 946 typedef void (icv_update_fn_t)(struct crypto_tfm *, struct scatterlist *, unsigned int);
 947
 948 extern void skb_icv_walk(const struct sk_buff *skb, struct crypto_tfm *tfm,
 949                          int offset, int len, icv_update_fn_t icv_update);
 950
 951 static inline int xfrm_addr_cmp(xfrm_address_t *a, xfrm_address_t *b,
 952                                 int family)
 953 {
 954         switch (family) {
 955         default:
 956         case AF_INET:
 957                 return a->a4 - b->a4;
 958         case AF_INET6:
 959                 return ipv6_addr_cmp((struct in6_addr *)a,
 960                                      (struct in6_addr *)b);
 961         }
 962 }
 963
 964 static inline int xfrm_policy_id2dir(u32 index)
 965 {
 966         return index & 7;
 967 }
 968
 969 #endif  /* _NET_XFRM_H */