1 /*
2 * IP Packet Parser Module.
3 *
4 * Copyright (C) 1999-2013, Broadcom Corporation
5 *
6 * Unless you and Broadcom execute a separate written software license
7 * agreement governing use of this software, this software is licensed to you
8 * under the terms of the GNU General Public License version 2 (the "GPL"),
9 * available at http://www.broadcom.com/licenses/GPLv2.php, with the
10 * following added to such license:
11 *
12 * As a special exception, the copyright holders of this software give you
13 * permission to link this software with independent modules, and to copy and
14 * distribute the resulting executable under terms of your choice, provided that
15 * you also meet, for each linked independent module, the terms and conditions of
16 * the license of that module. An independent module is a module which is not
17 * derived from this software. The special exception does not apply to any
18 * modifications of the software.
19 *
20 * Notwithstanding the above, under no circumstances may you combine this
21 * software in any way with any other Broadcom software provided under a license
22 * other than the GPL, without Broadcom's express prior written consent.
23 *
24 * $Id$
25 */
26 #include <typedefs.h>
27 #include <osl.h>
28
29 #include <proto/ethernet.h>
30 #include <proto/vlan.h>
31 #include <proto/802.3.h>
32 #include <proto/bcmip.h>
33 #include <bcmendian.h>
34
35 #include <dhd_dbg.h>
36
37 #include <dhd_ip.h>
38
39 /* special values */
40 /* 802.3 llc/snap header */
41 static const uint8 llc_snap_hdr[SNAP_HDR_LEN] = {0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00};
42
pkt_frag_info(osl_t * osh,void * p)43 pkt_frag_t pkt_frag_info(osl_t *osh, void *p)
44 {
45 uint8 *frame;
46 int length;
47 uint8 *pt; /* Pointer to type field */
48 uint16 ethertype;
49 struct ipv4_hdr *iph; /* IP frame pointer */
50 int ipl; /* IP frame length */
51 uint16 iph_frag;
52
53 ASSERT(osh && p);
54
55 frame = PKTDATA(osh, p);
56 length = PKTLEN(osh, p);
57
58 /* Process Ethernet II or SNAP-encapsulated 802.3 frames */
59 if (length < ETHER_HDR_LEN) {
60 DHD_INFO(("%s: short eth frame (%d)\n", __FUNCTION__, length));
61 return DHD_PKT_FRAG_NONE;
62 } else if (ntoh16(*(uint16 *)(frame + ETHER_TYPE_OFFSET)) >= ETHER_TYPE_MIN) {
63 /* Frame is Ethernet II */
64 pt = frame + ETHER_TYPE_OFFSET;
65 } else if (length >= ETHER_HDR_LEN + SNAP_HDR_LEN + ETHER_TYPE_LEN &&
66 !bcmp(llc_snap_hdr, frame + ETHER_HDR_LEN, SNAP_HDR_LEN)) {
67 pt = frame + ETHER_HDR_LEN + SNAP_HDR_LEN;
68 } else {
69 DHD_INFO(("%s: non-SNAP 802.3 frame\n", __FUNCTION__));
70 return DHD_PKT_FRAG_NONE;
71 }
72
73 ethertype = ntoh16(*(uint16 *)pt);
74
75 /* Skip VLAN tag, if any */
76 if (ethertype == ETHER_TYPE_8021Q) {
77 pt += VLAN_TAG_LEN;
78
79 if (pt + ETHER_TYPE_LEN > frame + length) {
80 DHD_INFO(("%s: short VLAN frame (%d)\n", __FUNCTION__, length));
81 return DHD_PKT_FRAG_NONE;
82 }
83
84 ethertype = ntoh16(*(uint16 *)pt);
85 }
86
87 if (ethertype != ETHER_TYPE_IP) {
88 DHD_INFO(("%s: non-IP frame (ethertype 0x%x, length %d)\n",
89 __FUNCTION__, ethertype, length));
90 return DHD_PKT_FRAG_NONE;
91 }
92
93 iph = (struct ipv4_hdr *)(pt + ETHER_TYPE_LEN);
94 ipl = length - (pt + ETHER_TYPE_LEN - frame);
95
96 /* We support IPv4 only */
97 if ((ipl < IPV4_OPTIONS_OFFSET) || (IP_VER(iph) != IP_VER_4)) {
98 DHD_INFO(("%s: short frame (%d) or non-IPv4\n", __FUNCTION__, ipl));
99 return DHD_PKT_FRAG_NONE;
100 }
101
102 iph_frag = ntoh16(iph->frag);
103
104 if (iph_frag & IPV4_FRAG_DONT) {
105 return DHD_PKT_FRAG_NONE;
106 } else if ((iph_frag & IPV4_FRAG_MORE) == 0) {
107 return DHD_PKT_FRAG_LAST;
108 } else {
109 return (iph_frag & IPV4_FRAG_OFFSET_MASK)? DHD_PKT_FRAG_CONT : DHD_PKT_FRAG_FIRST;
110 }
111 }
112