linux/net/ieee802154/header_ops.c
Thomas Gleixner 1802d0beec treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 655 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:41 -07:00

319 lines
6.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2014 Fraunhofer ITWM
*
* Written by:
* Phoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
*/
#include <linux/ieee802154.h>
#include <net/mac802154.h>
#include <net/ieee802154_netdev.h>
static int
ieee802154_hdr_push_addr(u8 *buf, const struct ieee802154_addr *addr,
bool omit_pan)
{
int pos = 0;
if (addr->mode == IEEE802154_ADDR_NONE)
return 0;
if (!omit_pan) {
memcpy(buf + pos, &addr->pan_id, 2);
pos += 2;
}
switch (addr->mode) {
case IEEE802154_ADDR_SHORT:
memcpy(buf + pos, &addr->short_addr, 2);
pos += 2;
break;
case IEEE802154_ADDR_LONG:
memcpy(buf + pos, &addr->extended_addr, IEEE802154_ADDR_LEN);
pos += IEEE802154_ADDR_LEN;
break;
default:
return -EINVAL;
}
return pos;
}
static int
ieee802154_hdr_push_sechdr(u8 *buf, const struct ieee802154_sechdr *hdr)
{
int pos = 5;
memcpy(buf, hdr, 1);
memcpy(buf + 1, &hdr->frame_counter, 4);
switch (hdr->key_id_mode) {
case IEEE802154_SCF_KEY_IMPLICIT:
return pos;
case IEEE802154_SCF_KEY_INDEX:
break;
case IEEE802154_SCF_KEY_SHORT_INDEX:
memcpy(buf + pos, &hdr->short_src, 4);
pos += 4;
break;
case IEEE802154_SCF_KEY_HW_INDEX:
memcpy(buf + pos, &hdr->extended_src, IEEE802154_ADDR_LEN);
pos += IEEE802154_ADDR_LEN;
break;
}
buf[pos++] = hdr->key_id;
return pos;
}
int
ieee802154_hdr_push(struct sk_buff *skb, struct ieee802154_hdr *hdr)
{
u8 buf[IEEE802154_MAX_HEADER_LEN];
int pos = 2;
int rc;
struct ieee802154_hdr_fc *fc = &hdr->fc;
buf[pos++] = hdr->seq;
fc->dest_addr_mode = hdr->dest.mode;
rc = ieee802154_hdr_push_addr(buf + pos, &hdr->dest, false);
if (rc < 0)
return -EINVAL;
pos += rc;
fc->source_addr_mode = hdr->source.mode;
if (hdr->source.pan_id == hdr->dest.pan_id &&
hdr->dest.mode != IEEE802154_ADDR_NONE)
fc->intra_pan = true;
rc = ieee802154_hdr_push_addr(buf + pos, &hdr->source, fc->intra_pan);
if (rc < 0)
return -EINVAL;
pos += rc;
if (fc->security_enabled) {
fc->version = 1;
rc = ieee802154_hdr_push_sechdr(buf + pos, &hdr->sec);
if (rc < 0)
return -EINVAL;
pos += rc;
}
memcpy(buf, fc, 2);
memcpy(skb_push(skb, pos), buf, pos);
return pos;
}
EXPORT_SYMBOL_GPL(ieee802154_hdr_push);
static int
ieee802154_hdr_get_addr(const u8 *buf, int mode, bool omit_pan,
struct ieee802154_addr *addr)
{
int pos = 0;
addr->mode = mode;
if (mode == IEEE802154_ADDR_NONE)
return 0;
if (!omit_pan) {
memcpy(&addr->pan_id, buf + pos, 2);
pos += 2;
}
if (mode == IEEE802154_ADDR_SHORT) {
memcpy(&addr->short_addr, buf + pos, 2);
return pos + 2;
} else {
memcpy(&addr->extended_addr, buf + pos, IEEE802154_ADDR_LEN);
return pos + IEEE802154_ADDR_LEN;
}
}
static int ieee802154_hdr_addr_len(int mode, bool omit_pan)
{
int pan_len = omit_pan ? 0 : 2;
switch (mode) {
case IEEE802154_ADDR_NONE: return 0;
case IEEE802154_ADDR_SHORT: return 2 + pan_len;
case IEEE802154_ADDR_LONG: return IEEE802154_ADDR_LEN + pan_len;
default: return -EINVAL;
}
}
static int
ieee802154_hdr_get_sechdr(const u8 *buf, struct ieee802154_sechdr *hdr)
{
int pos = 5;
memcpy(hdr, buf, 1);
memcpy(&hdr->frame_counter, buf + 1, 4);
switch (hdr->key_id_mode) {
case IEEE802154_SCF_KEY_IMPLICIT:
return pos;
case IEEE802154_SCF_KEY_INDEX:
break;
case IEEE802154_SCF_KEY_SHORT_INDEX:
memcpy(&hdr->short_src, buf + pos, 4);
pos += 4;
break;
case IEEE802154_SCF_KEY_HW_INDEX:
memcpy(&hdr->extended_src, buf + pos, IEEE802154_ADDR_LEN);
pos += IEEE802154_ADDR_LEN;
break;
}
hdr->key_id = buf[pos++];
return pos;
}
static int ieee802154_sechdr_lengths[4] = {
[IEEE802154_SCF_KEY_IMPLICIT] = 5,
[IEEE802154_SCF_KEY_INDEX] = 6,
[IEEE802154_SCF_KEY_SHORT_INDEX] = 10,
[IEEE802154_SCF_KEY_HW_INDEX] = 14,
};
static int ieee802154_hdr_sechdr_len(u8 sc)
{
return ieee802154_sechdr_lengths[IEEE802154_SCF_KEY_ID_MODE(sc)];
}
static int ieee802154_hdr_minlen(const struct ieee802154_hdr *hdr)
{
int dlen, slen;
dlen = ieee802154_hdr_addr_len(hdr->fc.dest_addr_mode, false);
slen = ieee802154_hdr_addr_len(hdr->fc.source_addr_mode,
hdr->fc.intra_pan);
if (slen < 0 || dlen < 0)
return -EINVAL;
return 3 + dlen + slen + hdr->fc.security_enabled;
}
static int
ieee802154_hdr_get_addrs(const u8 *buf, struct ieee802154_hdr *hdr)
{
int pos = 0;
pos += ieee802154_hdr_get_addr(buf + pos, hdr->fc.dest_addr_mode,
false, &hdr->dest);
pos += ieee802154_hdr_get_addr(buf + pos, hdr->fc.source_addr_mode,
hdr->fc.intra_pan, &hdr->source);
if (hdr->fc.intra_pan)
hdr->source.pan_id = hdr->dest.pan_id;
return pos;
}
int
ieee802154_hdr_pull(struct sk_buff *skb, struct ieee802154_hdr *hdr)
{
int pos = 3, rc;
if (!pskb_may_pull(skb, 3))
return -EINVAL;
memcpy(hdr, skb->data, 3);
rc = ieee802154_hdr_minlen(hdr);
if (rc < 0 || !pskb_may_pull(skb, rc))
return -EINVAL;
pos += ieee802154_hdr_get_addrs(skb->data + pos, hdr);
if (hdr->fc.security_enabled) {
int want = pos + ieee802154_hdr_sechdr_len(skb->data[pos]);
if (!pskb_may_pull(skb, want))
return -EINVAL;
pos += ieee802154_hdr_get_sechdr(skb->data + pos, &hdr->sec);
}
skb_pull(skb, pos);
return pos;
}
EXPORT_SYMBOL_GPL(ieee802154_hdr_pull);
int
ieee802154_hdr_peek_addrs(const struct sk_buff *skb, struct ieee802154_hdr *hdr)
{
const u8 *buf = skb_mac_header(skb);
int pos = 3, rc;
if (buf + 3 > skb_tail_pointer(skb))
return -EINVAL;
memcpy(hdr, buf, 3);
rc = ieee802154_hdr_minlen(hdr);
if (rc < 0 || buf + rc > skb_tail_pointer(skb))
return -EINVAL;
pos += ieee802154_hdr_get_addrs(buf + pos, hdr);
return pos;
}
EXPORT_SYMBOL_GPL(ieee802154_hdr_peek_addrs);
int
ieee802154_hdr_peek(const struct sk_buff *skb, struct ieee802154_hdr *hdr)
{
const u8 *buf = skb_mac_header(skb);
int pos;
pos = ieee802154_hdr_peek_addrs(skb, hdr);
if (pos < 0)
return -EINVAL;
if (hdr->fc.security_enabled) {
u8 key_id_mode = IEEE802154_SCF_KEY_ID_MODE(*(buf + pos));
int want = pos + ieee802154_sechdr_lengths[key_id_mode];
if (buf + want > skb_tail_pointer(skb))
return -EINVAL;
pos += ieee802154_hdr_get_sechdr(buf + pos, &hdr->sec);
}
return pos;
}
EXPORT_SYMBOL_GPL(ieee802154_hdr_peek);
int ieee802154_max_payload(const struct ieee802154_hdr *hdr)
{
int hlen = ieee802154_hdr_minlen(hdr);
if (hdr->fc.security_enabled) {
hlen += ieee802154_sechdr_lengths[hdr->sec.key_id_mode] - 1;
hlen += ieee802154_sechdr_authtag_len(&hdr->sec);
}
return IEEE802154_MTU - hlen - IEEE802154_MFR_SIZE;
}
EXPORT_SYMBOL_GPL(ieee802154_max_payload);