[src/trunk]: src/sys/dev/pcmcia Make sure the payload is aligned when using E...

[thorpej <thorpej%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/bf4e7635d828
branches:  trunk
changeset: 485245:bf4e7635d828
user:      thorpej <thorpej%NetBSD.org@localhost>
date:      Sat Apr 22 22:36:14 2000 +0000

description:
Make sure the payload is aligned when using E2-over-802.11 encapsulation,
as enabled by the LINK0 flag.  Fixes PR kern/9700.

diffstat:

 sys/dev/pcmcia/if_ray.c |  19 ++++++++++++++++---
 1 files changed, 16 insertions(+), 3 deletions(-)

diffs (54 lines):

diff -r 1e83df2d3b71 -r bf4e7635d828 sys/dev/pcmcia/if_ray.c
--- a/sys/dev/pcmcia/if_ray.c   Sat Apr 22 22:06:06 2000 +0000
+++ b/sys/dev/pcmcia/if_ray.c   Sat Apr 22 22:36:14 2000 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_ray.c,v 1.18 2000/03/26 20:25:30 kleink Exp $       */
+/*     $NetBSD: if_ray.c,v 1.19 2000/04/22 22:36:14 thorpej Exp $      */
 /* 
  * Copyright (c) 2000 Christian E. Hopps
  * All rights reserved.
@@ -1357,7 +1357,7 @@
        struct ieee80211_frame *frame;
        struct ether_header *eh;
        struct mbuf *m;
-       size_t pktlen, len, lenread;
+       size_t pktlen, fudge, len, lenread;
        bus_size_t bufp, ebufp, tmp;
        struct ifnet *ifp;
        u_int8_t *src, *d;
@@ -1377,6 +1377,18 @@
        m = 0;
        ifp = &sc->sc_if;
 
+       /*
+        * If we're expecting the E2-in-802.11 encapsulation that the
+        * WebGear Windows driver produces, fudge the packet forward
+        * in the mbuf by 2 bytes so that the payload after the
+        * Ethernet header will be aligned.  If we end up getting a
+        * packet that's not of this type, we'll just drop it anyway.
+        */
+       if (ifp->if_flags & IFF_LINK0)
+               fudge = 2;
+       else
+               fudge = 0;
+
        /* it looks like at least with build 4 there is no CRC in length */
        first = RAY_GET_INDEX(ccs);
        pktlen = SRAM_READ_FIELD_2(sc, ccs, ray_cmd_rx, c_pktlen);
@@ -1401,7 +1413,7 @@
                ifp->if_ierrors++;
                goto done;
        }
-       if (pktlen > MHLEN) {
+       if ((pktlen + fudge) > MHLEN) {
                /* XXX should allow chaining? */
                MCLGET(m, M_DONTWAIT);
                if ((m->m_flags & M_EXT) == 0) {
@@ -1415,6 +1427,7 @@
        m->m_pkthdr.rcvif = ifp;
        m->m_pkthdr.len = pktlen;
        m->m_len = pktlen;
+       m->m_data += fudge;
        d = mtod(m, u_int8_t *);
 
        RAY_DPRINTF(("%s: recv ccs index %d\n", sc->sc_xname, first));