Line data    Source code

       1             : /*      $OpenBSD: mpls_shim.c,v 1.8 2014/12/05 15:50:04 mpi Exp $       */
       2             : 
       3             : /*
       4             :  * Copyright (C) 1999, 2000 and 2001 AYAME Project, WIDE Project.
       5             :  * All rights reserved.
       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             :  *
      11             :  * 1. Redistributions of source code must retain the above copyright
      12             :  *    notice, this list of conditions and the following disclaimer.
      13             :  * 2. Redistributions in binary form must reproduce the above copyright
      14             :  *    notice, this list of conditions and the following disclaimer in the
      15             :  *    documentation and/or other materials provided with the distribution.
      16             :  * 3. Neither the name of the project nor the names of its contributors
      17             :  *    may be used to endorse or promote products derived from this software
      18             :  *    without specific prior written permission.
      19             :  *
      20             :  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
      21             :  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
      22             :  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
      23             :  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 
      24             :  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
      25             :  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 
      26             :  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
      27             :  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
      28             :  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 
      29             :  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 
      30             :  * SUCH DAMAGE.
      31             :  */
      32             : 
      33             : #include <sys/param.h>
      34             : #include <sys/mbuf.h>
      35             : #include <sys/errno.h>
      36             : #include <sys/socket.h>
      37             : #include <sys/systm.h>
      38             : 
      39             : #include <net/if.h>
      40             : #include <net/if_var.h>
      41             : 
      42             : #include <netmpls/mpls.h>
      43             : 
      44             : struct mbuf *
      45           0 : mpls_shim_pop(struct mbuf *m)
      46             : {
      47             :         /* shaves off top shim header from mbuf */
      48           0 :         m_adj(m, sizeof(struct shim_hdr));
      49             : 
      50             :         /* catch-up next shim_hdr */
      51           0 :         if (m->m_len < sizeof(struct shim_hdr))
      52           0 :                 if ((m = m_pullup(m, sizeof(struct shim_hdr))) == NULL)
      53           0 :                         return (NULL);
      54             : 
      55             :         /* return mbuf */
      56           0 :         return (m);
      57           0 : }
      58             : 
      59             : struct mbuf *
      60           0 : mpls_shim_swap(struct mbuf *m, struct rt_mpls *rt_mpls)
      61             : {
      62             :         struct shim_hdr *shim;
      63             : 
      64             :         /* pullup shim_hdr */
      65           0 :         if (m->m_len < sizeof(struct shim_hdr))
      66           0 :                 if ((m = m_pullup(m, sizeof(struct shim_hdr))) == NULL)
      67           0 :                         return (NULL);
      68           0 :         shim = mtod(m, struct shim_hdr *);
      69             : 
      70             :         /* swap label */
      71           0 :         shim->shim_label &= ~MPLS_LABEL_MASK;
      72           0 :         shim->shim_label |= rt_mpls->mpls_label & MPLS_LABEL_MASK;
      73             : 
      74             :         /* swap exp : XXX exp override */
      75             :         {
      76             :                 u_int32_t       t;
      77             : 
      78           0 :                 shim->shim_label &= ~MPLS_EXP_MASK;
      79           0 :                 t = rt_mpls->mpls_exp << MPLS_EXP_OFFSET;
      80           0 :                 shim->shim_label |= htonl(t) & MPLS_EXP_MASK;
      81             :         }
      82             : 
      83           0 :         return (m);
      84           0 : }
      85             : 
      86             : struct mbuf *
      87           0 : mpls_shim_push(struct mbuf *m, struct rt_mpls *rt_mpls)
      88             : {
      89             :         struct shim_hdr *shim;
      90             : 
      91           0 :         M_PREPEND(m, sizeof(struct shim_hdr), M_DONTWAIT);
      92           0 :         if (m == NULL)
      93           0 :                 return (NULL);
      94             : 
      95           0 :         shim = mtod(m, struct shim_hdr *);
      96           0 :         bzero((caddr_t)shim, sizeof(*shim));
      97             : 
      98           0 :         return (mpls_shim_swap(m, rt_mpls));
      99           0 : }