sys/netipsec/ipsec_osdep.h

   1 /*      $NetBSD: ipsec_osdep.h,v 1.21 2007/10/28 15:48:23 adrianp Exp $ */
   2 /*      $FreeBSD: /repoman/r/ncvs/src/sys/netipsec/ipsec_osdep.h,v 1.1 2003/09/29 22:47:45 sam Exp $    */
   3
   4 /*
   5  * Copyright (c) 2003 Jonathan Stone (jonathan@cs.stanford.edu)
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  18  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  19  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
  20  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  21  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  22  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  24  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  25  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  26  * POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #ifndef _NETIPSEC_OSDEP_H_
  30 #define _NETIPSEC_OSDEP_H_
  31
  32 #ifdef _KERNEL
  33 /*
  34  *  Hide porting differences across different 4.4BSD-derived platforms.
  35  *
  36  * 1.  KASSERT() differences:
  37  * 2.  Kernel  Random-number API differences.
  38  * 3.  Is packet data in an mbuf object writeable?
  39  * 4.  Packet-header semantics.
  40  * 5.  Fast mbuf-cluster allocation.
  41  * 6.  Network packet-output macros.
  42  * 7.  Elased time, in seconds.
  43  * 8.  Test if a  socket object opened by  a privileged (super) user.
  44  * 9.  Global SLIST of all open raw sockets.
  45  * 10. Global SLIST of known interface addresses.
  46  * 11. Type of initialization functions.
  47  * 12. Byte order of ip_off
  48  */
  49
  50 /*
  51  *  1. KASSERT and spl differences
  52  *
  53  * FreeBSD takes an expression and  parenthesized printf() argument-list.
  54  * NetBSD takes one arg: the expression being asserted.
  55  * FreeBSD's SPLASSERT() takes an SPL level as 1st arg and a
  56  * parenthesized printf-format argument list as the second argument.
  57  *
  58  * This difference is hidden by two 2-argument macros and one 1-arg macro:
  59  *    IPSEC_ASSERT(expr, msg)
  60  *    IPSEC_SPLASSERT(spl, msg)
  61  * One further difference is the spl names:
  62  *    NetBSD splsoftnet equates to FreeBSD splnet;
  63  *    NetBSD splnet equates to FreeBSD splimp.
  64  * which is hidden by the macro IPSEC_SPLASSERT_SOFTNET(msg).
  65  */
  66 #ifdef __FreeBSD__
  67 #define IPSEC_SPLASSERT(x,y) SPLASSERT(x, y)
  68 #define IPSEC_ASSERT(c,m) KASSERT(c, m)
  69 #define IPSEC_SPLASSERT_SOFTNET(m) SPLASSERT(splnet, m)
  70 #endif  /* __FreeBSD__ */
  71
  72 #ifdef  __NetBSD__
  73 #define IPSEC_SPLASSERT(x,y) (void)0
  74 #define IPSEC_ASSERT(c,m) KASSERT(c)
  75 #define IPSEC_SPLASSERT_SOFTNET(m) IPSEC_SPLASSERT(softnet, m)
  76 #endif  /* __NetBSD__ */
  77
  78 /*
  79  * 2. Kernel Randomness API.
  80  * FreeBSD uses:
  81  *    u_int read_random(void *outbuf, int nbytes).
  82  */
  83 #ifdef __FreeBSD__
  84 #include <sys/random.h>
  85 /* do nothing, use native random code. */
  86 #endif /* __FreeBSD__ */
  87
  88 #ifdef  __NetBSD__
  89 #include <sys/rnd.h>
  90 static __inline u_int read_random(void *p, u_int len);
  91
  92 static __inline u_int
  93 read_random(void *bufp, u_int len)
  94 {
  95         return rnd_extract_data(bufp, len, RND_EXTRACT_ANY /*XXX FIXME */);
  96 }
  97 #endif  /* __NetBSD__ */
  98
  99 /*
 100  * 3. Test for mbuf mutability
 101  * FreeBSD 4.x uses: M_EXT_WRITABLE
 102  * NetBSD has M_READONLY(). Use !M_READONLY().
 103  * Not an exact match to FreeBSD semantics, but adequate for IPsec purposes.
 104  *
 105  */
 106 #ifdef __NetBSD__
 107 /* XXX wrong, but close enough for restricted ipsec usage. */
 108 #define M_EXT_WRITABLE(m) (!M_READONLY(m))
 109 #endif  /* __NetBSD__ */
 110
 111 /*
 112  * 4. mbuf packet-header/packet-tag semantics.
 113  */
 114 /*
 115  * nothing.
 116  */
 117
 118 /*
 119  * 5. Fast mbuf-cluster allocation.
 120  */
 121 /*
 122  * nothing.
 123  */
 124
 125 /*
 126  * 6. Network output macros
 127  * FreeBSD uses the  IF_HANDOFF(), which raises SPL, enqueues
 128  * a packet, and updates interface counters. NetBSD has IFQ_ENQUE(),
 129  * which leaves SPL changes up to the caller.
 130  * For now, we provide an emulation of IF_HANOOFF() which works
 131  * for protocol input queues.
 132  */
 133 #ifdef __FreeBSD__
 134 /* nothing to do */
 135 #endif /* __FreeBSD__ */
 136 #ifdef __NetBSD__
 137 #define IF_HANDOFF(ifq, m, f) if_handoff(ifq, m, f, 0)
 138
 139 #include <net/if.h>
 140
 141 static __inline int
 142 if_handoff(struct ifqueue *ifq, struct mbuf *m, struct ifnet *ifp, int adjust)
 143 {
 144         int need_if_start = 0;
 145         int s = splnet();
 146
 147         if (IF_QFULL(ifq)) {
 148                 IF_DROP(ifq);
 149                 splx(s);
 150                 m_freem(m);
 151                 return (0);
 152         }
 153         if (ifp != NULL) {
 154                 ifp->if_obytes += m->m_pkthdr.len + adjust;
 155                 if (m->m_flags & M_MCAST)
 156                         ifp->if_omcasts++;
 157                 need_if_start = !(ifp->if_flags & IFF_OACTIVE);
 158         }
 159         IF_ENQUEUE(ifq, m);
 160         if (need_if_start)
 161                 (*ifp->if_start)(ifp);
 162         splx(s);
 163         return (1);
 164 }
 165 #endif /* __NetBSD__ */
 166
 167 /*
 168  * 7. Elapsed Time: time_second as time in seconds.
 169  * Original FreeBSD fast-ipsec code references a FreeBSD kernel global,
 170  * time_second().
 171  * XXX is this the right time scale - shouldn't we measure timeout/life times
 172  * using a monotonic time scale (time_uptime, mono_time) - why if the FreeBSD
 173  * base code using UTC based time for this ?
 174  */
 175
 176 /* protosw glue */
 177 #ifdef __NetBSD__
 178 #include <sys/protosw.h>
 179 #define ipprotosw protosw
 180 #endif  /* __NetBSD__ */
 181
 182 /*
 183  * 8. Test for "privileged" socket opened by superuser.
 184  * FreeBSD tests  ((so)->so_cred && (so)->so_cred.cr_uid == 0),
 185  * NetBSD (1.6N) tests (so)->so_uid == 0).
 186  * This difference is wrapped inside  the IPSEC_PRIVILEGED_SO() macro.
 187  *
 188  */
 189 #ifdef __FreeBSD__
 190 #define IPSEC_PRIVILEGED_SO(so) ((so)->so_cred && (so)->so_cred.cr_uid == 0)
 191 #endif  /* __FreeBSD__ */
 192
 193 #ifdef __NetBSD__
 194 /* superuser opened socket? */
 195 #define IPSEC_PRIVILEGED_SO(so) ((so)->so_uidinfo->ui_uid == 0)
 196 #endif  /* __NetBSD__ */
 197
 198 /*
 199  * 9. Raw socket list
 200  * FreeBSD uses: listhead = rawcb_list, SLIST()-next field "list".
 201  * NetBSD  uses: listhead = rawcb, SLIST()-next field "list"
 202  *
 203  * This version of fast-ipsec source code  uses rawcb_list as the head,
 204  *  and (to avoid namespace collisions) uses rcb_list as the "next" field.
 205  */
 206 #ifdef __FreeBSD__
 207 #define rcb_list list
 208 #endif /* __FreeBSD__ */
 209 #ifdef __NetBSD__
 210 #define rawcb_list rawcb
 211 #endif  /* __NetBSD__ */
 212
 213
 214 /*
 215  * 10. List of all known network interfaces.
 216  * FreeBSD has listhead in_ifaddrhead, with ia_link as link.
 217  * NetBSD has listhead in_ifaddr, with ia_list as link.
 218  * No name-clahses, so just #define the appropriate names on NetBSD.
 219  * NB: Is it worth introducing iterator (find-first-list/find-next-list)
 220  * functions or macros to encapsulate these?
 221  */
 222 #ifdef __FreeBSD__
 223 /* nothing to do for raw interface list */
 224 #endif  /* FreeBSD */
 225 #ifdef __NetBSD__
 226 #define ia_link ia_list
 227 #endif  /* __NetBSD__ */
 228
 229 /*
 230  * 11.  Type of initialization functions.
 231  */
 232 #ifdef __FreeBSD__
 233 #define INITFN static
 234 #endif
 235 #ifdef __NetBSD__
 236 #define INITFN extern
 237 #endif
 238
 239 /* 12. On FreeBSD, ip_off  assumed in host endian;
 240  * it is converted (if necessary) by ip_input().
 241  * On NetBSD, ip_off is in network byte order.
 242  * We hide the difference with the macro IP_OFF_CONVERT
 243  */
 244
 245 #ifdef __FreeBSD__
 246 #define IP_OFF_CONVERT(x) (x)
 247 #endif
 248
 249 #ifdef __NetBSD__
 250 #define IP_OFF_CONVERT(x) (htons(x))
 251 #endif
 252
 253 /*
 254  * 13. IPv6 support, and "generic" inpcb vs. IPv4 pcb vs. IPv6 pcb.
 255  * To IPv6 V4-mapped addresses (and the KAME-derived implementation
 256  * of IPv6 v4-mapped addresses)  we must support limited polymorphism:
 257  * partway down the stack we detect an IPv6 protocol address is really
 258  * a mapped V4 address, and then start dispatching that address to
 259  * native IPv4 PCB lookup. In KAME-derived IPsec (including fas-ipsec)
 260  * some functions must handle arguments which (dynamically) may be either
 261  * a IPv4 pcb (struct inpcb *) or an IPv6 pcb (struct in6pcb *).
 262  *
 263  * In FreeBSD 4.x, sgtrucr in6pcb is syntactic sugar for struct inpcb,
 264  * so punning between struct inpcb* and struct in6pcb* is trivial.
 265  * NetBSD until recently used completely different structs for IPv4
 266  * and IPv6 PCBs. To simplify fast-ipsec coexisting with IPv6,
 267  * NetBSD's struct inpcb and struct in6pcb were changed to both have
 268  * common struct, struct inpcb_hdr, as their first member.  NetBSD can
 269  * thus pass arguments as struct inpcb_hdr*, and dispatch on a v4/v6
 270  * flag in the inpcb_hdr at runtime.
 271  *
 272  * We hide the NetBSD-vs-FreeBSD differences inside the following abstraction:
 273  *
 274  *  PCB_T:  a macro name for a struct type which is used as a "generic"
 275  *      argument for actual arguments  an in4pcb or an in6pcb.
 276  *
 277  * PCB_FAMILY(p): given a "generic" pcb_t p, returns the protocol
 278  *      family (AF_INET, AF_INET6) of the unperlying inpcb/in6pcb.
 279  *
 280  * PCB_SOCKET(p): given a "generic" pcb_t p, returns the associated
 281  *      socket pointer
 282  *
 283  * PCB_TO_IN4PCB(p): given generic pcb_t *p, returns a struct inpcb *
 284  * PCB_TO_IN6PCB(p): given generic pcb_t *p, returns a struct in6pcb *
 285  *
 286  * IN4PCB_TO_PCB(inp):  given a struct inpcb *inp,   returns a pcb_t *
 287  * IN6PCB_TO_PCB(in6p): given a struct in6pcb *in6p, returns a pcb_t *
 288  */
 289 #ifdef __FreeBSD__
 290 #define PCB_T           struct inpcb
 291 #define PCB_FAMILY(p)   ((p)->inp_socket->so_proto->pr_domain->dom_family)
 292 #define PCB_SOCKET(p)   ((p)->inp_socket)
 293
 294 /* Convert generic pcb to IPv4/IPv6 pcb */
 295 #define PCB_TO_IN4PCB(p) (p)
 296 #define PCB_TO_IN6PCB(p) (p)
 297
 298 /* Convert IPv4/IPv6 pcb to generic pcb, for callers of fast-ipsec */
 299 #define IN4PCB_TO_PCB(p) (p)
 300 #define IN6PCB_TO_PCB(p) (p)
 301 #endif  /* __FreeBSD__ */
 302
 303 #ifdef __NetBSD__
 304 #define PCB_T           struct inpcb_hdr
 305 #define PCB_FAMILY(p)   ((p)->inph_af)
 306 #define PCB_SOCKET(p)   ((p)->inph_socket)
 307
 308 #define PCB_TO_IN4PCB(p) ((struct inpcb *)(p))
 309 #define PCB_TO_IN6PCB(p) ((struct in6pcb *)(p))
 310
 311 #define IN4PCB_TO_PCB(p) ((PCB_T *)(&(p)->inp_head))
 312 #define IN6PCB_TO_PCB(p) ((PCB_T *)(&(p)->in6p_head))
 313 #endif  /* __NetBSD__ */
 314
 315 /*
 316  * Differences that we don't attempt to hide:
 317  *
 318  * A. Initialization code.  This  is the largest difference of all.
 319  *
 320  *   FreeBSD uses compile/link-time perl hackery to generate special
 321  * .o files  with linker sections  that give the moral equivalent of
 322  * C++ file-level-object constructors. NetBSD has no such facility.
 323  *
 324  * Either we implement it (ideally, in a way that can emulate
 325  * FreeBSD's SYSINIT() macros), or we must take other means
 326  * to have the per-file init functions called at some appropriate time.
 327  *
 328  * In the absence of SYSINIT(), all the file-level init functions
 329  * now have "extern" linkage. There is a new fast-ipsec init()
 330  * function which calls each of the per-file in an appropriate order.
 331  * init_main will arrange to call the fast-ipsec init function
 332  * after the crypto framework has registered its transforms (including
 333  * any autoconfigured hardware crypto  accelerators) but before
 334  * initializing the network stack to send or receive  packet.
 335  *
 336  * B. Protosw() differences.
 337  * CSRG-style BSD TCP/IP uses a generic protocol-dispatch-function
 338  * where the specific request is identified by an enum argument.
 339  * FreeBSD replaced that with an array of request-specific
 340  * function pointers.
 341  *
 342  * These differences affect the handlers for key-protocol user requests
 343  * so pervasively that I gave up on the fast-ipsec code, and re-worked the
 344  * NetBSD KAME code to match the (relative few) API differences
 345  * between NetBSD and FreeBSD's KAME netkey, and Fast-IPsec netkey.
 346  *
 347  * C. Timeout() versus callout(9):
 348  * The FreeBSD 4.x netipsec/ code still uses timeout().
 349  * FreeBSD 4.7 has callout(9), so I just replaced
 350  * timeout_*() with the nearest callout_*() equivalents,
 351  * and added a callout handle to the ipsec context.
 352  *
 353  * D. SPL name differences.
 354  * FreeBSD splnet() equates directly to NetBSD's splsoftnet();
 355  * FreeBSD uses splimp() where (for networking) NetBSD would use splnet().
 356  */
 357 #endif /* _KERNEL */
 358 #endif /* !_NETIPSEC_OSDEP_H_ */