1 /*
2 * IE/TLV fragmentation/defragmentation support for
3 * Broadcom 802.11bang Networking Device Driver
4 *
5 * Portions of this code are copyright (c) 2021 Cypress Semiconductor Corporation
6 *
7 * Copyright (C) 1999-2017, Broadcom Corporation
8 *
9 * Unless you and Broadcom execute a separate written software license
10 * agreement governing use of this software, this software is licensed to you
11 * under the terms of the GNU General Public License version 2 (the "GPL"),
12 * available at http://www.broadcom.com/licenses/GPLv2.php, with the
13 * following added to such license:
14 *
15 * As a special exception, the copyright holders of this software give you
16 * permission to link this software with independent modules, and to copy and
17 * distribute the resulting executable under terms of your choice, provided that
18 * you also meet, for each linked independent module, the terms and conditions of
19 * the license of that module. An independent module is a module which is not
20 * derived from this software. The special exception does not apply to any
21 * modifications of the software.
22 *
23 * Notwithstanding the above, under no circumstances may you combine this
24 * software in any way with any other Broadcom software provided under a license
25 * other than the GPL, without Broadcom's express prior written consent.
26 * $Id$
27 *
28 * <<Broadcom-WL-IPTag/Open:>>
29 */
30
31 #include <bcmutils.h>
32 #include <frag.h>
33 #include <802.11.h>
34
35 /* defrag a fragmented dot11 ie/tlv. if space does not permit, return the needed
36 * ie length to contain all the fragments with status BCME_BUFTOOSHORT.
37 * out_len is in/out parameter, max length on input, used/required length on output
38 */
39 int
bcm_tlv_dot11_defrag(const void * buf,uint buf_len,uint8 id,bool id_ext,uint8 * out,uint * out_len)40 bcm_tlv_dot11_defrag(const void *buf, uint buf_len, uint8 id, bool id_ext,
41 uint8 *out, uint *out_len)
42 {
43 int err = BCME_OK;
44 const bcm_tlv_t *ie;
45 uint tot_len = 0;
46 uint out_left;
47
48 /* find the ie; includes validation */
49 ie = bcm_parse_tlvs_dot11(buf, buf_len, id, id_ext);
50 if (!ie) {
51 err = BCME_IE_NOTFOUND;
52 goto done;
53 }
54
55 out_left = (out && out_len) ? *out_len : 0;
56
57 /* first fragment */
58 tot_len = id_ext ? ie->len - 1 : ie->len;
59
60 /* copy out if output space permits */
61 if (out_left < tot_len) {
62 err = BCME_BUFTOOSHORT;
63 out_left = 0; /* prevent further copy */
64 } else {
65 memcpy(out, &ie->data[id_ext ? 1 : 0], tot_len);
66 out += tot_len;
67 out_left -= tot_len;
68 }
69
70 /* if not fragmened or not fragmentable per 802.11 table 9-77 11md0.1 bail
71 * we can introduce the latter check later
72 */
73 if (ie->len != BCM_TLV_MAX_DATA_SIZE) {
74 goto done;
75 }
76
77 /* adjust buf_len to length after ie including it */
78 buf_len -= (uint)(((const uint8 *)ie - (const uint8 *)buf));
79
80 /* update length from fragments, okay if no next ie */
81 while ((ie = bcm_next_tlv(ie, &buf_len)) &&
82 (ie->id == DOT11_MNG_FRAGMENT_ID)) {
83 /* note: buf_len starts at next ie and last frag may be partial */
84 if (out_left < ie->len) {
85 err = BCME_BUFTOOSHORT;
86 out_left = 0;
87 } else {
88 memcpy(out, &ie->data[0], ie->len);
89 out += ie->len;
90 out_left -= ie->len;
91 }
92
93 tot_len += ie->len + BCM_TLV_HDR_SIZE;
94
95 /* all but last should be of max size */
96 if (ie->len < BCM_TLV_MAX_DATA_SIZE) {
97 break;
98 }
99 }
100
101 done:
102 if (out_len) {
103 *out_len = tot_len;
104 }
105
106 return err;
107 }
108
109 int
bcm_tlv_dot11_frag_tot_len(const void * buf,uint buf_len,uint8 id,bool id_ext,uint * ie_len)110 bcm_tlv_dot11_frag_tot_len(const void *buf, uint buf_len,
111 uint8 id, bool id_ext, uint *ie_len)
112 {
113 return bcm_tlv_dot11_defrag(buf, buf_len, id, id_ext, NULL, ie_len);
114 }
115