include/net/xfrm.h

   1 #ifndef _NET_XFRM_H
   2 #define _NET_XFRM_H
   3
   4 #include <linux/compiler.h>
   5 #include <linux/xfrm.h>
   6 #include <linux/spinlock.h>
   7 #include <linux/list.h>
   8 #include <linux/skbuff.h>
   9 #include <linux/socket.h>
  10 #include <linux/pfkeyv2.h>
  11 #include <linux/ipsec.h>
  12 #include <linux/in6.h>
  13 #include <linux/mutex.h>
  14 #include <linux/audit.h>
  15 #include <linux/slab.h>
  16
  17 #include <net/sock.h>
  18 #include <net/dst.h>
  19 #include <net/ip.h>
  20 #include <net/route.h>
  21 #include <net/ipv6.h>
  22 #include <net/ip6_fib.h>
  23 #include <net/flow.h>
  24
  25 #include <linux/interrupt.h>
  26
  27 #ifdef CONFIG_XFRM_STATISTICS
  28 #include <net/snmp.h>
  29 #endif
  30
  31 #define XFRM_PROTO_ESP          50
  32 #define XFRM_PROTO_AH           51
  33 #define XFRM_PROTO_COMP         108
  34 #define XFRM_PROTO_IPIP         4
  35 #define XFRM_PROTO_IPV6         41
  36 #define XFRM_PROTO_ROUTING      IPPROTO_ROUTING
  37 #define XFRM_PROTO_DSTOPTS      IPPROTO_DSTOPTS
  38
  39 #define XFRM_ALIGN4(len)        (((len) + 3) & ~3)
  40 #define XFRM_ALIGN8(len)        (((len) + 7) & ~7)
  41 #define MODULE_ALIAS_XFRM_MODE(family, encap) \
  42         MODULE_ALIAS("xfrm-mode-" __stringify(family) "-" __stringify(encap))
  43 #define MODULE_ALIAS_XFRM_TYPE(family, proto) \
  44         MODULE_ALIAS("xfrm-type-" __stringify(family) "-" __stringify(proto))
  45
  46 #ifdef CONFIG_XFRM_STATISTICS
  47 #define XFRM_INC_STATS(net, field)      SNMP_INC_STATS((net)->mib.xfrm_statistics, field)
  48 #define XFRM_INC_STATS_BH(net, field)   SNMP_INC_STATS_BH((net)->mib.xfrm_statistics, field)
  49 #define XFRM_INC_STATS_USER(net, field) SNMP_INC_STATS_USER((net)-mib.xfrm_statistics, field)
  50 #else
  51 #define XFRM_INC_STATS(net, field)      ((void)(net))
  52 #define XFRM_INC_STATS_BH(net, field)   ((void)(net))
  53 #define XFRM_INC_STATS_USER(net, field) ((void)(net))
  54 #endif
  55
  56 extern struct mutex xfrm_cfg_mutex;
  57
  58 /* Organization of SPD aka "XFRM rules"
  59    ------------------------------------
  60
  61    Basic objects:
  62    - policy rule, struct xfrm_policy (=SPD entry)
  63    - bundle of transformations, struct dst_entry == struct xfrm_dst (=SA bundle)
  64    - instance of a transformer, struct xfrm_state (=SA)
  65    - template to clone xfrm_state, struct xfrm_tmpl
  66
  67    SPD is plain linear list of xfrm_policy rules, ordered by priority.
  68    (To be compatible with existing pfkeyv2 implementations,
  69    many rules with priority of 0x7fffffff are allowed to exist and
  70    such rules are ordered in an unpredictable way, thanks to bsd folks.)
  71
  72    Lookup is plain linear search until the first match with selector.
  73
  74    If "action" is "block", then we prohibit the flow, otherwise:
  75    if "xfrms_nr" is zero, the flow passes untransformed. Otherwise,
  76    policy entry has list of up to XFRM_MAX_DEPTH transformations,
  77    described by templates xfrm_tmpl. Each template is resolved
  78    to a complete xfrm_state (see below) and we pack bundle of transformations
  79    to a dst_entry returned to requestor.
  80
  81    dst -. xfrm  .-> xfrm_state #1
  82     |---. child .-> dst -. xfrm .-> xfrm_state #2
  83                      |---. child .-> dst -. xfrm .-> xfrm_state #3
  84                                       |---. child .-> NULL
  85
  86    Bundles are cached at xrfm_policy struct (field ->bundles).
  87
  88
  89    Resolution of xrfm_tmpl
  90    -----------------------
  91    Template contains:
  92    1. ->mode            Mode: transport or tunnel
  93    2. ->id.proto        Protocol: AH/ESP/IPCOMP
  94    3. ->id.daddr        Remote tunnel endpoint, ignored for transport mode.
  95       Q: allow to resolve security gateway?
  96    4. ->id.spi          If not zero, static SPI.
  97    5. ->saddr           Local tunnel endpoint, ignored for transport mode.
  98    6. ->algos           List of allowed algos. Plain bitmask now.
  99       Q: ealgos, aalgos, calgos. What a mess...
 100    7. ->share           Sharing mode.
 101       Q: how to implement private sharing mode? To add struct sock* to
 102       flow id?
 103
 104    Having this template we search through SAD searching for entries
 105    with appropriate mode/proto/algo, permitted by selector.
 106    If no appropriate entry found, it is requested from key manager.
 107
 108    PROBLEMS:
 109    Q: How to find all the bundles referring to a physical path for
 110       PMTU discovery? Seems, dst should contain list of all parents...
 111       and enter to infinite locking hierarchy disaster.
 112       No! It is easier, we will not search for them, let them find us.
 113       We add genid to each dst plus pointer to genid of raw IP route,
 114       pmtu disc will update pmtu on raw IP route and increase its genid.
 115       dst_check() will see this for top level and trigger resyncing
 116       metrics. Plus, it will be made via sk->sk_dst_cache. Solved.
 117  */
 118
 119 struct xfrm_state_walk {
 120         struct list_head        all;
 121         u8                      state;
 122         union {
 123                 u8              dying;
 124                 u8              proto;
 125         };
 126         u32                     seq;
 127 };
 128
 129 /* Full description of state of transformer. */
 130 struct xfrm_state {
 131 #ifdef CONFIG_NET_NS
 132         struct net              *xs_net;
 133 #endif
 134         union {
 135                 struct hlist_node       gclist;
 136                 struct hlist_node       bydst;
 137         };
 138         struct hlist_node       bysrc;
 139         struct hlist_node       byspi;
 140
 141         atomic_t                refcnt;
 142         spinlock_t              lock;
 143
 144         struct xfrm_id          id;
 145         struct xfrm_selector    sel;
 146         struct xfrm_mark        mark;
 147         u32                     tfcpad;
 148
 149         u32                     genid;
 150
 151         /* Key manager bits */
 152         struct xfrm_state_walk  km;
 153
 154         /* Parameters of this state. */
 155         struct {
 156                 u32             reqid;
 157                 u8              mode;
 158                 u8              replay_window;
 159                 u8              aalgo, ealgo, calgo;
 160                 u8              flags;
 161                 u16             family;
 162                 xfrm_address_t  saddr;
 163                 int             header_len;
 164                 int             trailer_len;
 165         } props;
 166
 167         struct xfrm_lifetime_cfg lft;
 168
 169         /* Data for transformer */
 170         struct xfrm_algo_auth   *aalg;
 171         struct xfrm_algo        *ealg;
 172         struct xfrm_algo        *calg;
 173         struct xfrm_algo_aead   *aead;
 174
 175         /* Data for encapsulator */
 176         struct xfrm_encap_tmpl  *encap;
 177
 178         /* Data for care-of address */
 179         xfrm_address_t  *coaddr;
 180
 181         /* IPComp needs an IPIP tunnel for handling uncompressed packets */
 182         struct xfrm_state       *tunnel;
 183
 184         /* If a tunnel, number of users + 1 */
 185         atomic_t                tunnel_users;
 186
 187         /* State for replay detection */
 188         struct xfrm_replay_state replay;
 189         struct xfrm_replay_state_esn *replay_esn;
 190
 191         /* Replay detection state at the time we sent the last notification */
 192         struct xfrm_replay_state preplay;
 193         struct xfrm_replay_state_esn *preplay_esn;
 194
 195         /* The functions for replay detection. */
 196         struct xfrm_replay      *repl;
 197
 198         /* internal flag that only holds state for delayed aevent at the
 199          * moment
 200         */
 201         u32                     xflags;
 202
 203         /* Replay detection notification settings */
 204         u32                     replay_maxage;
 205         u32                     replay_maxdiff;
 206
 207         /* Replay detection notification timer */
 208         struct timer_list       rtimer;
 209
 210         /* Statistics */
 211         struct xfrm_stats       stats;
 212
 213         struct xfrm_lifetime_cur curlft;
 214         struct tasklet_hrtimer  mtimer;
 215
 216         /* used to fix curlft->add_time when changing date */
 217         long            saved_tmo;
 218
 219         /* Last used time */
 220         unsigned long           lastused;
 221
 222         /* Reference to data common to all the instances of this
 223          * transformer. */
 224         const struct xfrm_type  *type;
 225         struct xfrm_mode        *inner_mode;
 226         struct xfrm_mode        *inner_mode_iaf;
 227         struct xfrm_mode        *outer_mode;
 228
 229         /* Security context */
 230         struct xfrm_sec_ctx     *security;
 231
 232         /* Private data of this transformer, format is opaque,
 233          * interpreted by xfrm_type methods. */
 234         void                    *data;
 235 };
 236
 237 static inline struct net *xs_net(struct xfrm_state *x)
 238 {
 239         return read_pnet(&x->xs_net);
 240 }
 241
 242 /* xflags - make enum if more show up */
 243 #define XFRM_TIME_DEFER 1
 244 #define XFRM_SOFT_EXPIRE 2
 245
 246 enum {
 247         XFRM_STATE_VOID,
 248         XFRM_STATE_ACQ,
 249         XFRM_STATE_VALID,
 250         XFRM_STATE_ERROR,
 251         XFRM_STATE_EXPIRED,
 252         XFRM_STATE_DEAD
 253 };
 254
 255 /* callback structure passed from either netlink or pfkey */
 256 struct km_event {
 257         union {
 258                 u32 hard;
 259                 u32 proto;
 260                 u32 byid;
 261                 u32 aevent;
 262                 u32 type;
 263         } data;
 264
 265         u32     seq;
 266         u32     pid;
 267         u32     event;
 268         struct net *net;
 269 };
 270
 271 struct xfrm_replay {
 272         void    (*advance)(struct xfrm_state *x, __be32 net_seq);
 273         int     (*check)(struct xfrm_state *x,
 274                          struct sk_buff *skb,
 275                          __be32 net_seq);
 276         int     (*recheck)(struct xfrm_state *x,
 277                            struct sk_buff *skb,
 278                            __be32 net_seq);
 279         void    (*notify)(struct xfrm_state *x, int event);
 280         int     (*overflow)(struct xfrm_state *x, struct sk_buff *skb);
 281 };
 282
 283 struct net_device;
 284 struct xfrm_type;
 285 struct xfrm_dst;
 286 struct xfrm_policy_afinfo {
 287         unsigned short          family;
 288         struct dst_ops          *dst_ops;
 289         void                    (*garbage_collect)(struct net *net);
 290         struct dst_entry        *(*dst_lookup)(struct net *net, int tos,
 291                                                const xfrm_address_t *saddr,
 292                                                const xfrm_address_t *daddr);
 293         int                     (*get_saddr)(struct net *net, xfrm_address_t *saddr, xfrm_address_t *daddr);
 294         void                    (*decode_session)(struct sk_buff *skb,
 295                                                   struct flowi *fl,
 296                                                   int reverse);
 297         int                     (*get_tos)(const struct flowi *fl);
 298         void                    (*init_dst)(struct net *net,
 299                                             struct xfrm_dst *dst);
 300         int                     (*init_path)(struct xfrm_dst *path,
 301                                              struct dst_entry *dst,
 302                                              int nfheader_len);
 303         int                     (*fill_dst)(struct xfrm_dst *xdst,
 304                                             struct net_device *dev,
 305                                             const struct flowi *fl);
 306         struct dst_entry        *(*blackhole_route)(struct net *net, struct dst_entry *orig);
 307 };
 308
 309 extern int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo);
 310 extern int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo);
 311 extern void km_policy_notify(struct xfrm_policy *xp, int dir, const struct km_event *c);
 312 extern void km_state_notify(struct xfrm_state *x, const struct km_event *c);
 313
 314 struct xfrm_tmpl;
 315 extern int km_query(struct xfrm_state *x, struct xfrm_tmpl *t, struct xfrm_policy *pol);
 316 extern void km_state_expired(struct xfrm_state *x, int hard, u32 pid);
 317 extern int __xfrm_state_delete(struct xfrm_state *x);
 318
 319 struct xfrm_state_afinfo {
 320         unsigned int            family;
 321         unsigned int            proto;
 322         __be16                  eth_proto;
 323         struct module           *owner;
 324         const struct xfrm_type  *type_map[IPPROTO_MAX];
 325         struct xfrm_mode        *mode_map[XFRM_MODE_MAX];
 326         int                     (*init_flags)(struct xfrm_state *x);
 327         void                    (*init_tempsel)(struct xfrm_selector *sel,
 328                                                 const struct flowi *fl);
 329         void                    (*init_temprop)(struct xfrm_state *x,
 330                                                 const struct xfrm_tmpl *tmpl,
 331                                                 const xfrm_address_t *daddr,
 332                                                 const xfrm_address_t *saddr);
 333         int                     (*tmpl_sort)(struct xfrm_tmpl **dst, struct xfrm_tmpl **src, int n);
 334         int                     (*state_sort)(struct xfrm_state **dst, struct xfrm_state **src, int n);
 335         int                     (*output)(struct sk_buff *skb);
 336         int                     (*output_finish)(struct sk_buff *skb);
 337         int                     (*extract_input)(struct xfrm_state *x,
 338                                                  struct sk_buff *skb);
 339         int                     (*extract_output)(struct xfrm_state *x,
 340                                                   struct sk_buff *skb);
 341         int                     (*transport_finish)(struct sk_buff *skb,
 342                                                     int async);
 343 };
 344
 345 extern int xfrm_state_register_afinfo(struct xfrm_state_afinfo *afinfo);
 346 extern int xfrm_state_unregister_afinfo(struct xfrm_state_afinfo *afinfo);
 347
 348 extern void xfrm_state_delete_tunnel(struct xfrm_state *x);
 349
 350 struct xfrm_type {
 351         char                    *description;
 352         struct module           *owner;
 353         u8                      proto;
 354         u8                      flags;
 355 #define XFRM_TYPE_NON_FRAGMENT  1
 356 #define XFRM_TYPE_REPLAY_PROT   2
 357 #define XFRM_TYPE_LOCAL_COADDR  4
 358 #define XFRM_TYPE_REMOTE_COADDR 8
 359
 360         int                     (*init_state)(struct xfrm_state *x);
 361         void                    (*destructor)(struct xfrm_state *);
 362         int                     (*input)(struct xfrm_state *, struct sk_buff *skb);
 363         int                     (*output)(struct xfrm_state *, struct sk_buff *pskb);
 364         int                     (*reject)(struct xfrm_state *, struct sk_buff *,
 365                                           const struct flowi *);
 366         int                     (*hdr_offset)(struct xfrm_state *, struct sk_buff *, u8 **);
 367         /* Estimate maximal size of result of transformation of a dgram */
 368         u32                     (*get_mtu)(struct xfrm_state *, int size);
 369 };
 370
 371 extern int xfrm_register_type(const struct xfrm_type *type, unsigned short family);
 372 extern int xfrm_unregister_type(const struct xfrm_type *type, unsigned short family);
 373
 374 struct xfrm_mode {
 375         /*
 376          * Remove encapsulation header.
 377          *
 378          * The IP header will be moved over the top of the encapsulation
 379          * header.
 380          *
 381          * On entry, the transport header shall point to where the IP header
 382          * should be and the network header shall be set to where the IP
 383          * header currently is.  skb->data shall point to the start of the
 384          * payload.
 385          */
 386         int (*input2)(struct xfrm_state *x, struct sk_buff *skb);
 387
 388         /*
 389          * This is the actual input entry point.
 390          *
 391          * For transport mode and equivalent this would be identical to
 392          * input2 (which does not need to be set).  While tunnel mode
 393          * and equivalent would set this to the tunnel encapsulation function
 394          * xfrm4_prepare_input that would in turn call input2.
 395          */
 396         int (*input)(struct xfrm_state *x, struct sk_buff *skb);
 397
 398         /*
 399          * Add encapsulation header.
 400          *
 401          * On exit, the transport header will be set to the start of the
 402          * encapsulation header to be filled in by x->type->output and
 403          * the mac header will be set to the nextheader (protocol for
 404          * IPv4) field of the extension header directly preceding the
 405          * encapsulation header, or in its absence, that of the top IP
 406          * header.  The value of the network header will always point
 407          * to the top IP header while skb->data will point to the payload.
 408          */
 409         int (*output2)(struct xfrm_state *x,struct sk_buff *skb);
 410
 411         /*
 412          * This is the actual output entry point.
 413          *
 414          * For transport mode and equivalent this would be identical to
 415          * output2 (which does not need to be set).  While tunnel mode
 416          * and equivalent would set this to a tunnel encapsulation function
 417          * (xfrm4_prepare_output or xfrm6_prepare_output) that would in turn
 418          * call output2.
 419          */
 420         int (*output)(struct xfrm_state *x, struct sk_buff *skb);
 421
 422         struct xfrm_state_afinfo *afinfo;
 423         struct module *owner;
 424         unsigned int encap;
 425         int flags;
 426 };
 427
 428 /* Flags for xfrm_mode. */
 429 enum {
 430         XFRM_MODE_FLAG_TUNNEL = 1,
 431 };
 432
 433 extern int xfrm_register_mode(struct xfrm_mode *mode, int family);
 434 extern int xfrm_unregister_mode(struct xfrm_mode *mode, int family);
 435
 436 static inline int xfrm_af2proto(unsigned int family)
 437 {
 438         switch(family) {
 439         case AF_INET:
 440                 return IPPROTO_IPIP;
 441         case AF_INET6:
 442                 return IPPROTO_IPV6;
 443         default:
 444                 return 0;
 445         }
 446 }
 447
 448 static inline struct xfrm_mode *xfrm_ip2inner_mode(struct xfrm_state *x, int ipproto)
 449 {
 450         if ((ipproto == IPPROTO_IPIP && x->props.family == AF_INET) ||
 451             (ipproto == IPPROTO_IPV6 && x->props.family == AF_INET6))
 452                 return x->inner_mode;
 453         else
 454                 return x->inner_mode_iaf;
 455 }
 456
 457 struct xfrm_tmpl {
 458 /* id in template is interpreted as:
 459  * daddr - destination of tunnel, may be zero for transport mode.
 460  * spi   - zero to acquire spi. Not zero if spi is static, then
 461  *         daddr must be fixed too.
 462  * proto - AH/ESP/IPCOMP
 463  */
 464         struct xfrm_id          id;
 465
 466 /* Source address of tunnel. Ignored, if it is not a tunnel. */
 467         xfrm_address_t          saddr;
 468
 469         unsigned short          encap_family;
 470
 471         u32                     reqid;
 472
 473 /* Mode: transport, tunnel etc. */
 474         u8                      mode;
 475
 476 /* Sharing mode: unique, this session only, this user only etc. */
 477         u8                      share;
 478
 479 /* May skip this transfomration if no SA is found */
 480         u8                      optional;
 481
 482 /* Skip aalgos/ealgos/calgos checks. */
 483         u8                      allalgs;
 484
 485 /* Bit mask of algos allowed for acquisition */
 486         u32                     aalgos;
 487         u32                     ealgos;
 488         u32                     calgos;
 489 };
 490
 491 #define XFRM_MAX_DEPTH          6
 492
 493 struct xfrm_policy_walk_entry {
 494         struct list_head        all;
 495         u8                      dead;
 496 };
 497
 498 struct xfrm_policy_walk {
 499         struct xfrm_policy_walk_entry walk;
 500         u8 type;
 501         u32 seq;
 502 };
 503
 504 struct xfrm_policy {
 505 #ifdef CONFIG_NET_NS
 506         struct net              *xp_net;
 507 #endif
 508         struct hlist_node       bydst;
 509         struct hlist_node       byidx;
 510
 511         /* This lock only affects elements except for entry. */
 512         rwlock_t                lock;
 513         atomic_t                refcnt;
 514         struct timer_list       timer;
 515
 516         struct flow_cache_object flo;
 517         atomic_t                genid;
 518         u32                     priority;
 519         u32                     index;
 520         struct xfrm_mark        mark;
 521         struct xfrm_selector    selector;
 522         struct xfrm_lifetime_cfg lft;
 523         struct xfrm_lifetime_cur curlft;
 524         struct xfrm_policy_walk_entry walk;
 525         u8                      type;
 526         u8                      action;
 527         u8                      flags;
 528         u8                      xfrm_nr;
 529         u16                     family;
 530         struct xfrm_sec_ctx     *security;
 531         struct xfrm_tmpl        xfrm_vec[XFRM_MAX_DEPTH];
 532 };
 533
 534 static inline struct net *xp_net(const struct xfrm_policy *xp)
 535 {
 536         return read_pnet(&xp->xp_net);
 537 }
 538
 539 struct xfrm_kmaddress {
 540         xfrm_address_t          local;
 541         xfrm_address_t          remote;
 542         u32                     reserved;
 543         u16                     family;
 544 };
 545
 546 struct xfrm_migrate {
 547         xfrm_address_t          old_daddr;
 548         xfrm_address_t          old_saddr;
 549         xfrm_address_t          new_daddr;
 550         xfrm_address_t          new_saddr;
 551         u8                      proto;
 552         u8                      mode;
 553         u16                     reserved;
 554         u32                     reqid;
 555         u16                     old_family;
 556         u16                     new_family;
 557 };
 558
 559 #define XFRM_KM_TIMEOUT                30
 560 /* which seqno */
 561 #define XFRM_REPLAY_SEQ         1
 562 #define XFRM_REPLAY_OSEQ        2
 563 #define XFRM_REPLAY_SEQ_MASK    3
 564 /* what happened */
 565 #define XFRM_REPLAY_UPDATE      XFRM_AE_CR
 566 #define XFRM_REPLAY_TIMEOUT     XFRM_AE_CE
 567
 568 /* default aevent timeout in units of 100ms */
 569 #define XFRM_AE_ETIME                   10
 570 /* Async Event timer multiplier */
 571 #define XFRM_AE_ETH_M                   10
 572 /* default seq threshold size */
 573 #define XFRM_AE_SEQT_SIZE               2
 574
 575 struct xfrm_mgr {
 576         struct list_head        list;
 577         char                    *id;
 578         int                     (*notify)(struct xfrm_state *x, const struct km_event *c);
 579         int                     (*acquire)(struct xfrm_state *x, struct xfrm_tmpl *, struct xfrm_policy *xp, int dir);
 580         struct xfrm_policy      *(*compile_policy)(struct sock *sk, int opt, u8 *data, int len, int *dir);
 581         int                     (*new_mapping)(struct xfrm_state *x, xfrm_address_t *ipaddr, __be16 sport);
 582         int                     (*notify_policy)(struct xfrm_policy *x, int dir, const struct km_event *c);
 583         int                     (*report)(struct net *net, u8 proto, struct xfrm_selector *sel, xfrm_address_t *addr);
 584         int                     (*migrate)(const struct xfrm_selector *sel,
 585                                            u8 dir, u8 type,
 586                                            const struct xfrm_migrate *m,
 587                                            int num_bundles,
 588                                            const struct xfrm_kmaddress *k);
 589 };
 590
 591 extern int xfrm_register_km(struct xfrm_mgr *km);
 592 extern int xfrm_unregister_km(struct xfrm_mgr *km);
 593
 594 /*
 595  * This structure is used for the duration where packets are being
 596  * transformed by IPsec.  As soon as the packet leaves IPsec the
 597  * area beyond the generic IP part may be overwritten.
 598  */
 599 struct xfrm_skb_cb {
 600         union {
 601                 struct inet_skb_parm h4;
 602                 struct inet6_skb_parm h6;
 603         } header;
 604
 605         /* Sequence number for replay protection. */
 606         union {
 607                 struct {
 608                         __u32 low;
 609                         __u32 hi;
 610                 } output;
 611                 struct {
 612                         __be32 low;
 613                         __be32 hi;
 614                 } input;
 615         } seq;
 616 };
 617
 618 #define XFRM_SKB_CB(__skb) ((struct xfrm_skb_cb *)&((__skb)->cb[0]))
 619
 620 /*
 621  * This structure is used by the afinfo prepare_input/prepare_output functions
 622  * to transmit header information to the mode input/output functions.
 623  */
 624 struct xfrm_mode_skb_cb {
 625         union {
 626                 struct inet_skb_parm h4;
 627                 struct inet6_skb_parm h6;
 628         } header;
 629
 630         /* Copied from header for IPv4, always set to zero and DF for IPv6. */
 631         __be16 id;
 632         __be16 frag_off;
 633
 634         /* IP header length (excluding options or extension headers). */
 635         u8 ihl;
 636
 637         /* TOS for IPv4, class for IPv6. */
 638         u8 tos;
 639
 640         /* TTL for IPv4, hop limitfor IPv6. */
 641         u8 ttl;
 642
 643         /* Protocol for IPv4, NH for IPv6. */
 644         u8 protocol;
 645
 646         /* Option length for IPv4, zero for IPv6. */
 647         u8 optlen;
 648
 649         /* Used by IPv6 only, zero for IPv4. */
 650         u8 flow_lbl[3];
 651 };
 652
 653 #define XFRM_MODE_SKB_CB(__skb) ((struct xfrm_mode_skb_cb *)&((__skb)->cb[0]))
 654
 655 /*
 656  * This structure is used by the input processing to locate the SPI and
 657  * related information.
 658  */
 659 struct xfrm_spi_skb_cb {
 660         union {
 661                 struct inet_skb_parm h4;
 662                 struct inet6_skb_parm h6;
 663         } header;
 664
 665         unsigned int daddroff;
 666         unsigned int family;
 667 };
 668
 669 #define XFRM_SPI_SKB_CB(__skb) ((struct xfrm_spi_skb_cb *)&((__skb)->cb[0]))
 670
 671 /* Audit Information */
 672 struct xfrm_audit {
 673         u32     secid;
 674         uid_t   loginuid;
 675         u32     sessionid;
 676 };
 677
 678 #ifdef CONFIG_AUDITSYSCALL
 679 static inline struct audit_buffer *xfrm_audit_start(const char *op)
 680 {
 681         struct audit_buffer *audit_buf = NULL;
 682
 683         if (audit_enabled == 0)
 684                 return NULL;
 685         audit_buf = audit_log_start(current->audit_context, GFP_ATOMIC,
 686                                     AUDIT_MAC_IPSEC_EVENT);
 687         if (audit_buf == NULL)
 688                 return NULL;
 689         audit_log_format(audit_buf, "op=%s", op);
 690         return audit_buf;
 691 }
 692
 693 static inline void xfrm_audit_helper_usrinfo(uid_t auid, u32 ses, u32 secid,
 694                                              struct audit_buffer *audit_buf)
 695 {
 696         char *secctx;
 697         u32 secctx_len;
 698
 699         audit_log_format(audit_buf, " auid=%u ses=%u", auid, ses);
 700         if (secid != 0 &&
 701             security_secid_to_secctx(secid, &secctx, &secctx_len) == 0) {
 702                 audit_log_format(audit_buf, " subj=%s", secctx);
 703                 security_release_secctx(secctx, secctx_len);
 704         } else
 705                 audit_log_task_context(audit_buf);
 706 }
 707
 708 extern void xfrm_audit_policy_add(struct xfrm_policy *xp, int result,
 709                                   u32 auid, u32 ses, u32 secid);
 710 extern void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
 711                                   u32 auid, u32 ses, u32 secid);
 712 extern void xfrm_audit_state_add(struct xfrm_state *x, int result,
 713                                  u32 auid, u32 ses, u32 secid);
 714 extern void xfrm_audit_state_delete(struct xfrm_state *x, int result,
 715                                     u32 auid, u32 ses, u32 secid);
 716 extern void xfrm_audit_state_replay_overflow(struct xfrm_state *x,
 717                                              struct sk_buff *skb);
 718 extern void xfrm_audit_state_replay(struct xfrm_state *x,
 719                                     struct sk_buff *skb, __be32 net_seq);
 720 extern void xfrm_audit_state_notfound_simple(struct sk_buff *skb, u16 family);
 721 extern void xfrm_audit_state_notfound(struct sk_buff *skb, u16 family,
 722                                       __be32 net_spi, __be32 net_seq);
 723 extern void xfrm_audit_state_icvfail(struct xfrm_state *x,
 724                                      struct sk_buff *skb, u8 proto);
 725 #else
 726
 727 static inline void xfrm_audit_policy_add(struct xfrm_policy *xp, int result,
 728                                   u32 auid, u32 ses, u32 secid)
 729 {
 730 }
 731
 732 static inline void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
 733                                   u32 auid, u32 ses, u32 secid)
 734 {
 735 }
 736
 737 static inline void xfrm_audit_state_add(struct xfrm_state *x, int result,
 738                                  u32 auid, u32 ses, u32 secid)
 739 {
 740 }
 741
 742 static inline void xfrm_audit_state_delete(struct xfrm_state *x, int result,
 743                                     u32 auid, u32 ses, u32 secid)
 744 {
 745 }
 746
 747 static inline void xfrm_audit_state_replay_overflow(struct xfrm_state *x,
 748                                              struct sk_buff *skb)
 749 {
 750 }
 751
 752 static inline void xfrm_audit_state_replay(struct xfrm_state *x,
 753                                            struct sk_buff *skb, __be32 net_seq)
 754 {
 755 }
 756
 757 static inline void xfrm_audit_state_notfound_simple(struct sk_buff *skb,
 758                                       u16 family)
 759 {
 760 }
 761
 762 static inline void xfrm_audit_state_notfound(struct sk_buff *skb, u16 family,
 763                                       __be32 net_spi, __be32 net_seq)
 764 {
 765 }
 766
 767 static inline void xfrm_audit_state_icvfail(struct xfrm_state *x,
 768                                      struct sk_buff *skb, u8 proto)
 769 {
 770 }
 771 #endif /* CONFIG_AUDITSYSCALL */
 772
 773 static inline void xfrm_pol_hold(struct xfrm_policy *policy)
 774 {
 775         if (likely(policy != NULL))
 776                 atomic_inc(&policy->refcnt);
 777 }
 778
 779 extern void xfrm_policy_destroy(struct xfrm_policy *policy);
 780
 781 static inline void xfrm_pol_put(struct xfrm_policy *policy)
 782 {
 783         if (atomic_dec_and_test(&policy->refcnt))
 784                 xfrm_policy_destroy(policy);
 785 }
 786
 787 static inline void xfrm_pols_put(struct xfrm_policy **pols, int npols)
 788 {
 789         int i;
 790         for (i = npols - 1; i >= 0; --i)
 791                 xfrm_pol_put(pols[i]);
 792 }
 793
 794 extern void __xfrm_state_destroy(struct xfrm_state *);
 795
 796 static inline void __xfrm_state_put(struct xfrm_state *x)
 797 {
 798         atomic_dec(&x->refcnt);
 799 }
 800
 801 static inline void xfrm_state_put(struct xfrm_state *x)
 802 {
 803         if (atomic_dec_and_test(&x->refcnt))
 804                 __xfrm_state_destroy(x);
 805 }
 806
 807 static inline void xfrm_state_hold(struct xfrm_state *x)
 808 {
 809         atomic_inc(&x->refcnt);
 810 }
 811
 812 static inline bool addr_match(const void *token1, const void *token2,
 813                               int prefixlen)
 814 {
 815         const __be32 *a1 = token1;
 816         const __be32 *a2 = token2;
 817         int pdw;
 818         int pbi;
 819
 820         pdw = prefixlen >> 5;     /* num of whole u32 in prefix */
 821         pbi = prefixlen &  0x1f;  /* num of bits in incomplete u32 in prefix */
 822
 823         if (pdw)
 824                 if (memcmp(a1, a2, pdw << 2))
 825                         return false;
 826
 827         if (pbi) {
 828                 __be32 mask;
 829
 830                 mask = htonl((0xffffffff) << (32 - pbi));
 831
 832                 if ((a1[pdw] ^ a2[pdw]) & mask)
 833                         return false;
 834         }
 835
 836         return true;
 837 }
 838
 839 static inline bool addr4_match(__be32 a1, __be32 a2, u8 prefixlen)
 840 {
 841         /* C99 6.5.7 (3): u32 << 32 is undefined behaviour */
 842         if (prefixlen == 0)
 843                 return true;
 844         return !((a1 ^ a2) & htonl(0xFFFFFFFFu << (32 - prefixlen)));
 845 }
 846
 847 static __inline__
 848 __be16 xfrm_flowi_sport(const struct flowi *fl, const union flowi_uli *uli)
 849 {
 850         __be16 port;
 851         switch(fl->flowi_proto) {
 852         case IPPROTO_TCP:
 853         case IPPROTO_UDP:
 854         case IPPROTO_UDPLITE:
 855         case IPPROTO_SCTP:
 856                 port = uli->ports.sport;
 857                 break;
 858         case IPPROTO_ICMP:
 859         case IPPROTO_ICMPV6:
 860                 port = htons(uli->icmpt.type);
 861                 break;
 862         case IPPROTO_MH:
 863                 port = htons(uli->mht.type);
 864                 break;
 865         case IPPROTO_GRE:
 866                 port = htons(ntohl(uli->gre_key) >> 16);
 867                 break;
 868         default:
 869                 port = 0;       /*XXX*/
 870         }
 871         return port;
 872 }
 873
 874 static __inline__
 875 __be16 xfrm_flowi_dport(const struct flowi *fl, const union flowi_uli *uli)
 876 {
 877         __be16 port;
 878         switch(fl->flowi_proto) {
 879         case IPPROTO_TCP:
 880         case IPPROTO_UDP:
 881         case IPPROTO_UDPLITE:
 882         case IPPROTO_SCTP:
 883                 port = uli->ports.dport;
 884                 break;
 885         case IPPROTO_ICMP:
 886         case IPPROTO_ICMPV6:
 887                 port = htons(uli->icmpt.code);
 888                 break;
 889         case IPPROTO_GRE:
 890                 port = htons(ntohl(uli->gre_key) & 0xffff);
 891                 break;
 892         default:
 893                 port = 0;       /*XXX*/
 894         }
 895         return port;
 896 }
 897
 898 extern bool xfrm_selector_match(const struct xfrm_selector *sel,
 899                                 const struct flowi *fl,
 900                                 unsigned short family);
 901
 902 #ifdef CONFIG_SECURITY_NETWORK_XFRM
 903 /*      If neither has a context --> match
 904  *      Otherwise, both must have a context and the sids, doi, alg must match
 905  */
 906 static inline bool xfrm_sec_ctx_match(struct xfrm_sec_ctx *s1, struct xfrm_sec_ctx *s2)
 907 {
 908         return ((!s1 && !s2) ||
 909                 (s1 && s2 &&
 910                  (s1->ctx_sid == s2->ctx_sid) &&
 911                  (s1->ctx_doi == s2->ctx_doi) &&
 912                  (s1->ctx_alg == s2->ctx_alg)));
 913 }
 914 #else
 915 static inline bool xfrm_sec_ctx_match(struct xfrm_sec_ctx *s1, struct xfrm_sec_ctx *s2)
 916 {
 917         return true;
 918 }
 919 #endif
 920
 921 /* A struct encoding bundle of transformations to apply to some set of flow.
 922  *
 923  * dst->child points to the next element of bundle.
 924  * dst->xfrm  points to an instanse of transformer.
 925  *
 926  * Due to unfortunate limitations of current routing cache, which we
 927  * have no time to fix, it mirrors struct rtable and bound to the same
 928  * routing key, including saddr,daddr. However, we can have many of
 929  * bundles differing by session id. All the bundles grow from a parent
 930  * policy rule.
 931  */
 932 struct xfrm_dst {
 933         union {
 934                 struct dst_entry        dst;
 935                 struct rtable           rt;
 936                 struct rt6_info         rt6;
 937         } u;
 938         struct dst_entry *route;
 939         struct flow_cache_object flo;
 940         struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
 941         int num_pols, num_xfrms;
 942 #ifdef CONFIG_XFRM_SUB_POLICY
 943         struct flowi *origin;
 944         struct xfrm_selector *partner;
 945 #endif
 946         u32 xfrm_genid;
 947         u32 policy_genid;
 948         u32 route_mtu_cached;
 949         u32 child_mtu_cached;
 950         u32 route_cookie;
 951         u32 path_cookie;
 952 };
 953
 954 #ifdef CONFIG_XFRM
 955 static inline void xfrm_dst_destroy(struct xfrm_dst *xdst)
 956 {
 957         xfrm_pols_put(xdst->pols, xdst->num_pols);
 958         dst_release(xdst->route);
 959         if (likely(xdst->u.dst.xfrm))
 960                 xfrm_state_put(xdst->u.dst.xfrm);
 961 #ifdef CONFIG_XFRM_SUB_POLICY
 962         kfree(xdst->origin);
 963         xdst->origin = NULL;
 964         kfree(xdst->partner);
 965         xdst->partner = NULL;
 966 #endif
 967 }
 968 #endif
 969
 970 extern void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev);
 971
 972 struct sec_path {
 973         atomic_t                refcnt;
 974         int                     len;
 975         struct xfrm_state       *xvec[XFRM_MAX_DEPTH];
 976 };
 977
 978 static inline int secpath_exists(struct sk_buff *skb)
 979 {
 980 #ifdef CONFIG_XFRM
 981         return skb->sp != NULL;
 982 #else
 983         return 0;
 984 #endif
 985 }
 986
 987 static inline struct sec_path *
 988 secpath_get(struct sec_path *sp)
 989 {
 990         if (sp)
 991                 atomic_inc(&sp->refcnt);
 992         return sp;
 993 }
 994
 995 extern void __secpath_destroy(struct sec_path *sp);
 996
 997 static inline void
 998 secpath_put(struct sec_path *sp)
 999 {
1000         if (sp && atomic_dec_and_test(&sp->refcnt))
1001                 __secpath_destroy(sp);
1002 }
1003
1004 extern struct sec_path *secpath_dup(struct sec_path *src);
1005
1006 static inline void
1007 secpath_reset(struct sk_buff *skb)
1008 {
1009 #ifdef CONFIG_XFRM
1010         secpath_put(skb->sp);
1011         skb->sp = NULL;
1012 #endif
1013 }
1014
1015 static inline int
1016 xfrm_addr_any(const xfrm_address_t *addr, unsigned short family)
1017 {
1018         switch (family) {
1019         case AF_INET:
1020                 return addr->a4 == 0;
1021         case AF_INET6:
1022                 return ipv6_addr_any((struct in6_addr *)&addr->a6);
1023         }
1024         return 0;
1025 }
1026
1027 static inline int
1028 __xfrm4_state_addr_cmp(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x)
1029 {
1030         return  (tmpl->saddr.a4 &&
1031                  tmpl->saddr.a4 != x->props.saddr.a4);
1032 }
1033
1034 static inline int
1035 __xfrm6_state_addr_cmp(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x)
1036 {
1037         return  (!ipv6_addr_any((struct in6_addr*)&tmpl->saddr) &&
1038                  ipv6_addr_cmp((struct in6_addr *)&tmpl->saddr, (struct in6_addr*)&x->props.saddr));
1039 }
1040
1041 static inline int
1042 xfrm_state_addr_cmp(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x, unsigned short family)
1043 {
1044         switch (family) {
1045         case AF_INET:
1046                 return __xfrm4_state_addr_cmp(tmpl, x);
1047         case AF_INET6:
1048                 return __xfrm6_state_addr_cmp(tmpl, x);
1049         }
1050         return !0;
1051 }
1052
1053 #ifdef CONFIG_XFRM
1054 extern int __xfrm_policy_check(struct sock *, int dir, struct sk_buff *skb, unsigned short family);
1055
1056 static inline int __xfrm_policy_check2(struct sock *sk, int dir,
1057                                        struct sk_buff *skb,
1058                                        unsigned int family, int reverse)
1059 {
1060         struct net *net = dev_net(skb->dev);
1061         int ndir = dir | (reverse ? XFRM_POLICY_MASK + 1 : 0);
1062
1063         if (sk && sk->sk_policy[XFRM_POLICY_IN])
1064                 return __xfrm_policy_check(sk, ndir, skb, family);
1065
1066         return  (!net->xfrm.policy_count[dir] && !skb->sp) ||
1067                 (skb_dst(skb)->flags & DST_NOPOLICY) ||
1068                 __xfrm_policy_check(sk, ndir, skb, family);
1069 }
1070
1071 static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
1072 {
1073         return __xfrm_policy_check2(sk, dir, skb, family, 0);
1074 }
1075
1076 static inline int xfrm4_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
1077 {
1078         return xfrm_policy_check(sk, dir, skb, AF_INET);
1079 }
1080
1081 static inline int xfrm6_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
1082 {
1083         return xfrm_policy_check(sk, dir, skb, AF_INET6);
1084 }
1085
1086 static inline int xfrm4_policy_check_reverse(struct sock *sk, int dir,
1087                                              struct sk_buff *skb)
1088 {
1089         return __xfrm_policy_check2(sk, dir, skb, AF_INET, 1);
1090 }
1091
1092 static inline int xfrm6_policy_check_reverse(struct sock *sk, int dir,
1093                                              struct sk_buff *skb)
1094 {
1095         return __xfrm_policy_check2(sk, dir, skb, AF_INET6, 1);
1096 }
1097
1098 extern int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
1099                                  unsigned int family, int reverse);
1100
1101 static inline int xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
1102                                       unsigned int family)
1103 {
1104         return __xfrm_decode_session(skb, fl, family, 0);
1105 }
1106
1107 static inline int xfrm_decode_session_reverse(struct sk_buff *skb,
1108                                               struct flowi *fl,
1109                                               unsigned int family)
1110 {
1111         return __xfrm_decode_session(skb, fl, family, 1);
1112 }
1113
1114 extern int __xfrm_route_forward(struct sk_buff *skb, unsigned short family);
1115
1116 static inline int xfrm_route_forward(struct sk_buff *skb, unsigned short family)
1117 {
1118         struct net *net = dev_net(skb->dev);
1119
1120         return  !net->xfrm.policy_count[XFRM_POLICY_OUT] ||
1121                 (skb_dst(skb)->flags & DST_NOXFRM) ||
1122                 __xfrm_route_forward(skb, family);
1123 }
1124
1125 static inline int xfrm4_route_forward(struct sk_buff *skb)
1126 {
1127         return xfrm_route_forward(skb, AF_INET);
1128 }
1129
1130 static inline int xfrm6_route_forward(struct sk_buff *skb)
1131 {
1132         return xfrm_route_forward(skb, AF_INET6);
1133 }
1134
1135 extern int __xfrm_sk_clone_policy(struct sock *sk);
1136
1137 static inline int xfrm_sk_clone_policy(struct sock *sk)
1138 {
1139         if (unlikely(sk->sk_policy[0] || sk->sk_policy[1]))
1140                 return __xfrm_sk_clone_policy(sk);
1141         return 0;
1142 }
1143
1144 extern int xfrm_policy_delete(struct xfrm_policy *pol, int dir);
1145
1146 static inline void xfrm_sk_free_policy(struct sock *sk)
1147 {
1148         if (unlikely(sk->sk_policy[0] != NULL)) {
1149                 xfrm_policy_delete(sk->sk_policy[0], XFRM_POLICY_MAX);
1150                 sk->sk_policy[0] = NULL;
1151         }
1152         if (unlikely(sk->sk_policy[1] != NULL)) {
1153                 xfrm_policy_delete(sk->sk_policy[1], XFRM_POLICY_MAX+1);
1154                 sk->sk_policy[1] = NULL;
1155         }
1156 }
1157
1158 #else
1159
1160 static inline void xfrm_sk_free_policy(struct sock *sk) {}
1161 static inline int xfrm_sk_clone_policy(struct sock *sk) { return 0; }
1162 static inline int xfrm6_route_forward(struct sk_buff *skb) { return 1; }
1163 static inline int xfrm4_route_forward(struct sk_buff *skb) { return 1; }
1164 static inline int xfrm6_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
1165 {
1166         return 1;
1167 }
1168 static inline int xfrm4_policy_check(struct sock *sk, int dir, struct sk_buff *skb)
1169 {
1170         return 1;
1171 }
1172 static inline int xfrm_policy_check(struct sock *sk, int dir, struct sk_buff *skb, unsigned short family)
1173 {
1174         return 1;
1175 }
1176 static inline int xfrm_decode_session_reverse(struct sk_buff *skb,
1177                                               struct flowi *fl,
1178                                               unsigned int family)
1179 {
1180         return -ENOSYS;
1181 }
1182 static inline int xfrm4_policy_check_reverse(struct sock *sk, int dir,
1183                                              struct sk_buff *skb)
1184 {
1185         return 1;
1186 }
1187 static inline int xfrm6_policy_check_reverse(struct sock *sk, int dir,
1188                                              struct sk_buff *skb)
1189 {
1190         return 1;
1191 }
1192 #endif
1193
1194 static __inline__
1195 xfrm_address_t *xfrm_flowi_daddr(const struct flowi *fl, unsigned short family)
1196 {
1197         switch (family){
1198         case AF_INET:
1199                 return (xfrm_address_t *)&fl->u.ip4.daddr;
1200         case AF_INET6:
1201                 return (xfrm_address_t *)&fl->u.ip6.daddr;
1202         }
1203         return NULL;
1204 }
1205
1206 static __inline__
1207 xfrm_address_t *xfrm_flowi_saddr(const struct flowi *fl, unsigned short family)
1208 {
1209         switch (family){
1210         case AF_INET:
1211                 return (xfrm_address_t *)&fl->u.ip4.saddr;
1212         case AF_INET6:
1213                 return (xfrm_address_t *)&fl->u.ip6.saddr;
1214         }
1215         return NULL;
1216 }
1217
1218 static __inline__
1219 void xfrm_flowi_addr_get(const struct flowi *fl,
1220                          xfrm_address_t *saddr, xfrm_address_t *daddr,
1221                          unsigned short family)
1222 {
1223         switch(family) {
1224         case AF_INET:
1225                 memcpy(&saddr->a4, &fl->u.ip4.saddr, sizeof(saddr->a4));
1226                 memcpy(&daddr->a4, &fl->u.ip4.daddr, sizeof(daddr->a4));
1227                 break;
1228         case AF_INET6:
1229                 *(struct in6_addr *)saddr->a6 = fl->u.ip6.saddr;
1230                 *(struct in6_addr *)daddr->a6 = fl->u.ip6.daddr;
1231                 break;
1232         }
1233 }
1234
1235 static __inline__ int
1236 __xfrm4_state_addr_check(const struct xfrm_state *x,
1237                          const xfrm_address_t *daddr, const xfrm_address_t *saddr)
1238 {
1239         if (daddr->a4 == x->id.daddr.a4 &&
1240             (saddr->a4 == x->props.saddr.a4 || !saddr->a4 || !x->props.saddr.a4))
1241                 return 1;
1242         return 0;
1243 }
1244
1245 static __inline__ int
1246 __xfrm6_state_addr_check(const struct xfrm_state *x,
1247                          const xfrm_address_t *daddr, const xfrm_address_t *saddr)
1248 {
1249         if (!ipv6_addr_cmp((struct in6_addr *)daddr, (struct in6_addr *)&x->id.daddr) &&
1250             (!ipv6_addr_cmp((struct in6_addr *)saddr, (struct in6_addr *)&x->props.saddr)||
1251              ipv6_addr_any((struct in6_addr *)saddr) ||
1252              ipv6_addr_any((struct in6_addr *)&x->props.saddr)))
1253                 return 1;
1254         return 0;
1255 }
1256
1257 static __inline__ int
1258 xfrm_state_addr_check(const struct xfrm_state *x,
1259                       const xfrm_address_t *daddr, const xfrm_address_t *saddr,
1260                       unsigned short family)
1261 {
1262         switch (family) {
1263         case AF_INET:
1264                 return __xfrm4_state_addr_check(x, daddr, saddr);
1265         case AF_INET6:
1266                 return __xfrm6_state_addr_check(x, daddr, saddr);
1267         }
1268         return 0;
1269 }
1270
1271 static __inline__ int
1272 xfrm_state_addr_flow_check(const struct xfrm_state *x, const struct flowi *fl,
1273                            unsigned short family)
1274 {
1275         switch (family) {
1276         case AF_INET:
1277                 return __xfrm4_state_addr_check(x,
1278                                                 (const xfrm_address_t *)&fl->u.ip4.daddr,
1279                                                 (const xfrm_address_t *)&fl->u.ip4.saddr);
1280         case AF_INET6:
1281                 return __xfrm6_state_addr_check(x,
1282                                                 (const xfrm_address_t *)&fl->u.ip6.daddr,
1283                                                 (const xfrm_address_t *)&fl->u.ip6.saddr);
1284         }
1285         return 0;
1286 }
1287
1288 static inline int xfrm_state_kern(const struct xfrm_state *x)
1289 {
1290         return atomic_read(&x->tunnel_users);
1291 }
1292
1293 static inline int xfrm_id_proto_match(u8 proto, u8 userproto)
1294 {
1295         return (!userproto || proto == userproto ||
1296                 (userproto == IPSEC_PROTO_ANY && (proto == IPPROTO_AH ||
1297                                                   proto == IPPROTO_ESP ||
1298                                                   proto == IPPROTO_COMP)));
1299 }
1300
1301 /*
1302  * xfrm algorithm information
1303  */
1304 struct xfrm_algo_aead_info {
1305         u16 icv_truncbits;
1306 };
1307
1308 struct xfrm_algo_auth_info {
1309         u16 icv_truncbits;
1310         u16 icv_fullbits;
1311 };
1312
1313 struct xfrm_algo_encr_info {
1314         u16 blockbits;
1315         u16 defkeybits;
1316 };
1317
1318 struct xfrm_algo_comp_info {
1319         u16 threshold;
1320 };
1321
1322 struct xfrm_algo_desc {
1323         char *name;
1324         char *compat;
1325         u8 available:1;
1326         union {
1327                 struct xfrm_algo_aead_info aead;
1328                 struct xfrm_algo_auth_info auth;
1329                 struct xfrm_algo_encr_info encr;
1330                 struct xfrm_algo_comp_info comp;
1331         } uinfo;
1332         struct sadb_alg desc;
1333 };
1334
1335 /* XFRM tunnel handlers.  */
1336 struct xfrm_tunnel {
1337         int (*handler)(struct sk_buff *skb);
1338         int (*err_handler)(struct sk_buff *skb, u32 info);
1339
1340         struct xfrm_tunnel __rcu *next;
1341         int priority;
1342 };
1343
1344 struct xfrm6_tunnel {
1345         int (*handler)(struct sk_buff *skb);
1346         int (*err_handler)(struct sk_buff *skb, struct inet6_skb_parm *opt,
1347                            u8 type, u8 code, int offset, __be32 info);
1348         struct xfrm6_tunnel __rcu *next;
1349         int priority;
1350 };
1351
1352 extern void xfrm_init(void);
1353 extern void xfrm4_init(int rt_hash_size);
1354 extern int xfrm_state_init(struct net *net);
1355 extern void xfrm_state_fini(struct net *net);
1356 extern void xfrm4_state_init(void);
1357 #ifdef CONFIG_XFRM
1358 extern int xfrm6_init(void);
1359 extern void xfrm6_fini(void);
1360 extern int xfrm6_state_init(void);
1361 extern void xfrm6_state_fini(void);
1362 #else
1363 static inline int xfrm6_init(void)
1364 {
1365         return 0;
1366 }
1367 static inline void xfrm6_fini(void)
1368 {
1369         ;
1370 }
1371 #endif
1372
1373 #ifdef CONFIG_XFRM_STATISTICS
1374 extern int xfrm_proc_init(struct net *net);
1375 extern void xfrm_proc_fini(struct net *net);
1376 #endif
1377
1378 extern int xfrm_sysctl_init(struct net *net);
1379 #ifdef CONFIG_SYSCTL
1380 extern void xfrm_sysctl_fini(struct net *net);
1381 #else
1382 static inline void xfrm_sysctl_fini(struct net *net)
1383 {
1384 }
1385 #endif
1386
1387 extern void xfrm_state_walk_init(struct xfrm_state_walk *walk, u8 proto);
1388 extern int xfrm_state_walk(struct net *net, struct xfrm_state_walk *walk,
1389                            int (*func)(struct xfrm_state *, int, void*), void *);
1390 extern void xfrm_state_walk_done(struct xfrm_state_walk *walk);
1391 extern struct xfrm_state *xfrm_state_alloc(struct net *net);
1392 extern struct xfrm_state *xfrm_state_find(const xfrm_address_t *daddr,
1393                                           const xfrm_address_t *saddr,
1394                                           const struct flowi *fl,
1395                                           struct xfrm_tmpl *tmpl,
1396                                           struct xfrm_policy *pol, int *err,
1397                                           unsigned short family);
1398 extern struct xfrm_state *xfrm_stateonly_find(struct net *net, u32 mark,
1399                                                xfrm_address_t *daddr,
1400                                                xfrm_address_t *saddr,
1401                                                unsigned short family,
1402                                                u8 mode, u8 proto, u32 reqid);
1403 extern int xfrm_state_check_expire(struct xfrm_state *x);
1404 extern void xfrm_state_insert(struct xfrm_state *x);
1405 extern int xfrm_state_add(struct xfrm_state *x);
1406 extern int xfrm_state_update(struct xfrm_state *x);
1407 extern struct xfrm_state *xfrm_state_lookup(struct net *net, u32 mark,
1408                                             const xfrm_address_t *daddr, __be32 spi,
1409                                             u8 proto, unsigned short family);
1410 extern struct xfrm_state *xfrm_state_lookup_byaddr(struct net *net, u32 mark,
1411                                                    const xfrm_address_t *daddr,
1412                                                    const xfrm_address_t *saddr,
1413                                                    u8 proto,
1414                                                    unsigned short family);
1415 #ifdef CONFIG_XFRM_SUB_POLICY
1416 extern int xfrm_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src,
1417                           int n, unsigned short family);
1418 extern int xfrm_state_sort(struct xfrm_state **dst, struct xfrm_state **src,
1419                            int n, unsigned short family);
1420 #else
1421 static inline int xfrm_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src,
1422                                  int n, unsigned short family)
1423 {
1424         return -ENOSYS;
1425 }
1426
1427 static inline int xfrm_state_sort(struct xfrm_state **dst, struct xfrm_state **src,
1428                                   int n, unsigned short family)
1429 {
1430         return -ENOSYS;
1431 }
1432 #endif
1433
1434 struct xfrmk_sadinfo {
1435         u32 sadhcnt; /* current hash bkts */
1436         u32 sadhmcnt; /* max allowed hash bkts */
1437         u32 sadcnt; /* current running count */
1438 };
1439
1440 struct xfrmk_spdinfo {
1441         u32 incnt;
1442         u32 outcnt;
1443         u32 fwdcnt;
1444         u32 inscnt;
1445         u32 outscnt;
1446         u32 fwdscnt;
1447         u32 spdhcnt;
1448         u32 spdhmcnt;
1449 };
1450
1451 extern struct xfrm_state *xfrm_find_acq_byseq(struct net *net, u32 mark,
1452                                               u32 seq);
1453 extern int xfrm_state_delete(struct xfrm_state *x);
1454 extern int xfrm_state_flush(struct net *net, u8 proto, struct xfrm_audit *audit_info);
1455 extern void xfrm_sad_getinfo(struct net *net, struct xfrmk_sadinfo *si);
1456 extern void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si);
1457 extern u32 xfrm_replay_seqhi(struct xfrm_state *x, __be32 net_seq);
1458 extern int xfrm_init_replay(struct xfrm_state *x);
1459 extern int xfrm_state_mtu(struct xfrm_state *x, int mtu);
1460 extern int __xfrm_init_state(struct xfrm_state *x, bool init_replay);
1461 extern int xfrm_init_state(struct xfrm_state *x);
1462 extern int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb);
1463 extern int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi,
1464                       int encap_type);
1465 extern int xfrm_input_resume(struct sk_buff *skb, int nexthdr);
1466 extern int xfrm_output_resume(struct sk_buff *skb, int err);
1467 extern int xfrm_output(struct sk_buff *skb);
1468 extern int xfrm_inner_extract_output(struct xfrm_state *x, struct sk_buff *skb);
1469 extern int xfrm4_extract_header(struct sk_buff *skb);
1470 extern int xfrm4_extract_input(struct xfrm_state *x, struct sk_buff *skb);
1471 extern int xfrm4_rcv_encap(struct sk_buff *skb, int nexthdr, __be32 spi,
1472                            int encap_type);
1473 extern int xfrm4_transport_finish(struct sk_buff *skb, int async);
1474 extern int xfrm4_rcv(struct sk_buff *skb);
1475
1476 static inline int xfrm4_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi)
1477 {
1478         return xfrm4_rcv_encap(skb, nexthdr, spi, 0);
1479 }
1480
1481 extern int xfrm4_extract_output(struct xfrm_state *x, struct sk_buff *skb);
1482 extern int xfrm4_prepare_output(struct xfrm_state *x, struct sk_buff *skb);
1483 extern int xfrm4_output(struct sk_buff *skb);
1484 extern int xfrm4_output_finish(struct sk_buff *skb);
1485 extern int xfrm4_tunnel_register(struct xfrm_tunnel *handler, unsigned short family);
1486 extern int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler, unsigned short family);
1487 extern int xfrm4_mode_tunnel_input_register(struct xfrm_tunnel *handler);
1488 extern int xfrm4_mode_tunnel_input_deregister(struct xfrm_tunnel *handler);
1489 extern int xfrm6_extract_header(struct sk_buff *skb);
1490 extern int xfrm6_extract_input(struct xfrm_state *x, struct sk_buff *skb);
1491 extern int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi);
1492 extern int xfrm6_transport_finish(struct sk_buff *skb, int async);
1493 extern int xfrm6_rcv(struct sk_buff *skb);
1494 extern int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
1495                             xfrm_address_t *saddr, u8 proto);
1496 extern int xfrm6_tunnel_register(struct xfrm6_tunnel *handler, unsigned short family);
1497 extern int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler, unsigned short family);
1498 extern __be32 xfrm6_tunnel_alloc_spi(struct net *net, xfrm_address_t *saddr);
1499 extern __be32 xfrm6_tunnel_spi_lookup(struct net *net, const xfrm_address_t *saddr);
1500 extern int xfrm6_extract_output(struct xfrm_state *x, struct sk_buff *skb);
1501 extern int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb);
1502 extern int xfrm6_output(struct sk_buff *skb);
1503 extern int xfrm6_output_finish(struct sk_buff *skb);
1504 extern int xfrm6_find_1stfragopt(struct xfrm_state *x, struct sk_buff *skb,
1505                                  u8 **prevhdr);
1506
1507 #ifdef CONFIG_XFRM
1508 extern int xfrm4_udp_encap_rcv(struct sock *sk, struct sk_buff *skb);
1509 extern int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen);
1510 #else
1511 static inline int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen)
1512 {
1513         return -ENOPROTOOPT;
1514 }
1515
1516 static inline int xfrm4_udp_encap_rcv(struct sock *sk, struct sk_buff *skb)
1517 {
1518         /* should not happen */
1519         kfree_skb(skb);
1520         return 0;
1521 }
1522 #endif
1523
1524 struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp);
1525
1526 extern void xfrm_policy_walk_init(struct xfrm_policy_walk *walk, u8 type);
1527 extern int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
1528         int (*func)(struct xfrm_policy *, int, int, void*), void *);
1529 extern void xfrm_policy_walk_done(struct xfrm_policy_walk *walk);
1530 int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl);
1531 struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark,
1532                                           u8 type, int dir,
1533                                           struct xfrm_selector *sel,
1534                                           struct xfrm_sec_ctx *ctx, int delete,
1535                                           int *err);
1536 struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8, int dir, u32 id, int delete, int *err);
1537 int xfrm_policy_flush(struct net *net, u8 type, struct xfrm_audit *audit_info);
1538 u32 xfrm_get_acqseq(void);
1539 extern int xfrm_alloc_spi(struct xfrm_state *x, u32 minspi, u32 maxspi);
1540 struct xfrm_state *xfrm_find_acq(struct net *net, struct xfrm_mark *mark,
1541                                  u8 mode, u32 reqid, u8 proto,
1542                                  const xfrm_address_t *daddr,
1543                                  const xfrm_address_t *saddr, int create,
1544                                  unsigned short family);
1545 extern int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol);
1546
1547 #ifdef CONFIG_XFRM_MIGRATE
1548 extern int km_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
1549                       const struct xfrm_migrate *m, int num_bundles,
1550                       const struct xfrm_kmaddress *k);
1551 extern struct xfrm_state * xfrm_migrate_state_find(struct xfrm_migrate *m);
1552 extern struct xfrm_state * xfrm_state_migrate(struct xfrm_state *x,
1553                                               struct xfrm_migrate *m);
1554 extern int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
1555                         struct xfrm_migrate *m, int num_bundles,
1556                         struct xfrm_kmaddress *k);
1557 #endif
1558
1559 extern int km_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr, __be16 sport);
1560 extern void km_policy_expired(struct xfrm_policy *pol, int dir, int hard, u32 pid);
1561 extern int km_report(struct net *net, u8 proto, struct xfrm_selector *sel, xfrm_address_t *addr);
1562
1563 extern void xfrm_input_init(void);
1564 extern int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq);
1565
1566 extern void xfrm_probe_algs(void);
1567 extern int xfrm_count_auth_supported(void);
1568 extern int xfrm_count_enc_supported(void);
1569 extern struct xfrm_algo_desc *xfrm_aalg_get_byidx(unsigned int idx);
1570 extern struct xfrm_algo_desc *xfrm_ealg_get_byidx(unsigned int idx);
1571 extern struct xfrm_algo_desc *xfrm_aalg_get_byid(int alg_id);
1572 extern struct xfrm_algo_desc *xfrm_ealg_get_byid(int alg_id);
1573 extern struct xfrm_algo_desc *xfrm_calg_get_byid(int alg_id);
1574 extern struct xfrm_algo_desc *xfrm_aalg_get_byname(const char *name, int probe);
1575 extern struct xfrm_algo_desc *xfrm_ealg_get_byname(const char *name, int probe);
1576 extern struct xfrm_algo_desc *xfrm_calg_get_byname(const char *name, int probe);
1577 extern struct xfrm_algo_desc *xfrm_aead_get_byname(const char *name, int icv_len,
1578                                                    int probe);
1579
1580 static inline int xfrm_addr_cmp(const xfrm_address_t *a,
1581                                 const xfrm_address_t *b,
1582                                 int family)
1583 {
1584         switch (family) {
1585         default:
1586         case AF_INET:
1587                 return (__force u32)a->a4 - (__force u32)b->a4;
1588         case AF_INET6:
1589                 return ipv6_addr_cmp((const struct in6_addr *)a,
1590                                      (const struct in6_addr *)b);
1591         }
1592 }
1593
1594 static inline int xfrm_policy_id2dir(u32 index)
1595 {
1596         return index & 7;
1597 }
1598
1599 #ifdef CONFIG_XFRM
1600 static inline int xfrm_aevent_is_on(struct net *net)
1601 {
1602         struct sock *nlsk;
1603         int ret = 0;
1604
1605         rcu_read_lock();
1606         nlsk = rcu_dereference(net->xfrm.nlsk);
1607         if (nlsk)
1608                 ret = netlink_has_listeners(nlsk, XFRMNLGRP_AEVENTS);
1609         rcu_read_unlock();
1610         return ret;
1611 }
1612 #endif
1613
1614 static inline int xfrm_alg_len(const struct xfrm_algo *alg)
1615 {
1616         return sizeof(*alg) + ((alg->alg_key_len + 7) / 8);
1617 }
1618
1619 static inline int xfrm_alg_auth_len(const struct xfrm_algo_auth *alg)
1620 {
1621         return sizeof(*alg) + ((alg->alg_key_len + 7) / 8);
1622 }
1623
1624 static inline int xfrm_replay_state_esn_len(struct xfrm_replay_state_esn *replay_esn)
1625 {
1626         return sizeof(*replay_esn) + replay_esn->bmp_len * sizeof(__u32);
1627 }
1628
1629 #ifdef CONFIG_XFRM_MIGRATE
1630 static inline int xfrm_replay_clone(struct xfrm_state *x,
1631                                      struct xfrm_state *orig)
1632 {
1633         x->replay_esn = kzalloc(xfrm_replay_state_esn_len(orig->replay_esn),
1634                                 GFP_KERNEL);
1635         if (!x->replay_esn)
1636                 return -ENOMEM;
1637
1638         x->replay_esn->bmp_len = orig->replay_esn->bmp_len;
1639         x->replay_esn->replay_window = orig->replay_esn->replay_window;
1640
1641         x->preplay_esn = kmemdup(x->replay_esn,
1642                                  xfrm_replay_state_esn_len(x->replay_esn),
1643                                  GFP_KERNEL);
1644         if (!x->preplay_esn) {
1645                 kfree(x->replay_esn);
1646                 return -ENOMEM;
1647         }
1648
1649         return 0;
1650 }
1651
1652 static inline struct xfrm_algo *xfrm_algo_clone(struct xfrm_algo *orig)
1653 {
1654         return kmemdup(orig, xfrm_alg_len(orig), GFP_KERNEL);
1655 }
1656
1657 static inline struct xfrm_algo_auth *xfrm_algo_auth_clone(struct xfrm_algo_auth *orig)
1658 {
1659         return kmemdup(orig, xfrm_alg_auth_len(orig), GFP_KERNEL);
1660 }
1661
1662 static inline void xfrm_states_put(struct xfrm_state **states, int n)
1663 {
1664         int i;
1665         for (i = 0; i < n; i++)
1666                 xfrm_state_put(*(states + i));
1667 }
1668
1669 static inline void xfrm_states_delete(struct xfrm_state **states, int n)
1670 {
1671         int i;
1672         for (i = 0; i < n; i++)
1673                 xfrm_state_delete(*(states + i));
1674 }
1675 #endif
1676
1677 #ifdef CONFIG_XFRM
1678 static inline struct xfrm_state *xfrm_input_state(struct sk_buff *skb)
1679 {
1680         return skb->sp->xvec[skb->sp->len - 1];
1681 }
1682 #endif
1683
1684 static inline int xfrm_mark_get(struct nlattr **attrs, struct xfrm_mark *m)
1685 {
1686         if (attrs[XFRMA_MARK])
1687                 memcpy(m, nla_data(attrs[XFRMA_MARK]), sizeof(struct xfrm_mark));
1688         else
1689                 m->v = m->m = 0;
1690
1691         return m->v & m->m;
1692 }
1693
1694 static inline int xfrm_mark_put(struct sk_buff *skb, const struct xfrm_mark *m)
1695 {
1696         int ret = 0;
1697
1698         if (m->m | m->v)
1699                 ret = nla_put(skb, XFRMA_MARK, sizeof(struct xfrm_mark), m);
1700         return ret;
1701 }
1702
1703 #endif  /* _NET_XFRM_H */