--- /dev/null
+/* 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.
+ */
+
+#include <net/6lowpan.h>
+#include <net/ieee802154_netdev.h>
+
+#include "6lowpan_i.h"
+
+/* don't save pan id, it's intra pan */
+struct lowpan_addr {
+ u8 mode;
+ union {
+ /* IPv6 needs big endian here */
+ __be64 extended_addr;
+ __be16 short_addr;
+ } u;
+};
+
+struct lowpan_addr_info {
+ struct lowpan_addr daddr;
+ struct lowpan_addr saddr;
+};
+
+static inline struct
+lowpan_addr_info *lowpan_skb_priv(const struct sk_buff *skb)
+{
+ WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct lowpan_addr_info));
+ return (struct lowpan_addr_info *)(skb->data -
+ sizeof(struct lowpan_addr_info));
+}
+
+int lowpan_header_create(struct sk_buff *skb, struct net_device *dev,
+ unsigned short type, const void *_daddr,
+ const void *_saddr, unsigned int len)
+{
+ const u8 *saddr = _saddr;
+ const u8 *daddr = _daddr;
+ struct lowpan_addr_info *info;
+
+ /* TODO:
+ * if this package isn't ipv6 one, where should it be routed?
+ */
+ if (type != ETH_P_IPV6)
+ return 0;
+
+ if (!saddr)
+ saddr = dev->dev_addr;
+
+ raw_dump_inline(__func__, "saddr", (unsigned char *)saddr, 8);
+ raw_dump_inline(__func__, "daddr", (unsigned char *)daddr, 8);
+
+ info = lowpan_skb_priv(skb);
+
+ /* TODO: Currently we only support extended_addr */
+ info->daddr.mode = IEEE802154_ADDR_LONG;
+ memcpy(&info->daddr.u.extended_addr, daddr,
+ sizeof(info->daddr.u.extended_addr));
+ info->saddr.mode = IEEE802154_ADDR_LONG;
+ memcpy(&info->saddr.u.extended_addr, saddr,
+ sizeof(info->daddr.u.extended_addr));
+
+ return 0;
+}
+
+static struct sk_buff*
+lowpan_alloc_frag(struct sk_buff *skb, int size,
+ const struct ieee802154_hdr *master_hdr)
+{
+ struct net_device *real_dev = lowpan_dev_info(skb->dev)->real_dev;
+ struct sk_buff *frag;
+ int rc;
+
+ frag = alloc_skb(real_dev->hard_header_len +
+ real_dev->needed_tailroom + size,
+ GFP_ATOMIC);
+
+ if (likely(frag)) {
+ frag->dev = real_dev;
+ frag->priority = skb->priority;
+ skb_reserve(frag, real_dev->hard_header_len);
+ skb_reset_network_header(frag);
+ *mac_cb(frag) = *mac_cb(skb);
+
+ rc = dev_hard_header(frag, real_dev, 0, &master_hdr->dest,
+ &master_hdr->source, size);
+ if (rc < 0) {
+ kfree_skb(frag);
+ return ERR_PTR(rc);
+ }
+ } else {
+ frag = ERR_PTR(-ENOMEM);
+ }
+
+ return frag;
+}
+
+static int
+lowpan_xmit_fragment(struct sk_buff *skb, const struct ieee802154_hdr *wpan_hdr,
+ u8 *frag_hdr, int frag_hdrlen,
+ int offset, int len)
+{
+ struct sk_buff *frag;
+
+ raw_dump_inline(__func__, " fragment header", frag_hdr, frag_hdrlen);
+
+ frag = lowpan_alloc_frag(skb, frag_hdrlen + len, wpan_hdr);
+ if (IS_ERR(frag))
+ return -PTR_ERR(frag);
+
+ memcpy(skb_put(frag, frag_hdrlen), frag_hdr, frag_hdrlen);
+ memcpy(skb_put(frag, len), skb_network_header(skb) + offset, len);
+
+ raw_dump_table(__func__, " fragment dump", frag->data, frag->len);
+
+ return dev_queue_xmit(frag);
+}
+
+static int
+lowpan_xmit_fragmented(struct sk_buff *skb, struct net_device *dev,
+ const struct ieee802154_hdr *wpan_hdr)
+{
+ u16 dgram_size, dgram_offset;
+ __be16 frag_tag;
+ u8 frag_hdr[5];
+ int frag_cap, frag_len, payload_cap, rc;
+ int skb_unprocessed, skb_offset;
+
+ dgram_size = lowpan_uncompress_size(skb, &dgram_offset) -
+ skb->mac_len;
+ frag_tag = htons(lowpan_dev_info(dev)->fragment_tag);
+ lowpan_dev_info(dev)->fragment_tag++;
+
+ frag_hdr[0] = LOWPAN_DISPATCH_FRAG1 | ((dgram_size >> 8) & 0x07);
+ frag_hdr[1] = dgram_size & 0xff;
+ memcpy(frag_hdr + 2, &frag_tag, sizeof(frag_tag));
+
+ payload_cap = ieee802154_max_payload(wpan_hdr);
+
+ frag_len = round_down(payload_cap - LOWPAN_FRAG1_HEAD_SIZE -
+ skb_network_header_len(skb), 8);
+
+ skb_offset = skb_network_header_len(skb);
+ skb_unprocessed = skb->len - skb->mac_len - skb_offset;
+
+ rc = lowpan_xmit_fragment(skb, wpan_hdr, frag_hdr,
+ LOWPAN_FRAG1_HEAD_SIZE, 0,
+ frag_len + skb_network_header_len(skb));
+ if (rc) {
+ pr_debug("%s unable to send FRAG1 packet (tag: %d)",
+ __func__, ntohs(frag_tag));
+ goto err;
+ }
+
+ frag_hdr[0] &= ~LOWPAN_DISPATCH_FRAG1;
+ frag_hdr[0] |= LOWPAN_DISPATCH_FRAGN;
+ frag_cap = round_down(payload_cap - LOWPAN_FRAGN_HEAD_SIZE, 8);
+
+ do {
+ dgram_offset += frag_len;
+ skb_offset += frag_len;
+ skb_unprocessed -= frag_len;
+ frag_len = min(frag_cap, skb_unprocessed);
+
+ frag_hdr[4] = dgram_offset >> 3;
+
+ rc = lowpan_xmit_fragment(skb, wpan_hdr, frag_hdr,
+ LOWPAN_FRAGN_HEAD_SIZE, skb_offset,
+ frag_len);
+ if (rc) {
+ pr_debug("%s unable to send a FRAGN packet. (tag: %d, offset: %d)\n",
+ __func__, ntohs(frag_tag), skb_offset);
+ goto err;
+ }
+ } while (skb_unprocessed > frag_cap);
+
+ consume_skb(skb);
+ return NET_XMIT_SUCCESS;
+
+err:
+ kfree_skb(skb);
+ return rc;
+}
+
+static int lowpan_header(struct sk_buff *skb, struct net_device *dev)
+{
+ struct ieee802154_addr sa, da;
+ struct ieee802154_mac_cb *cb = mac_cb_init(skb);
+ struct lowpan_addr_info info;
+ void *daddr, *saddr;
+
+ memcpy(&info, lowpan_skb_priv(skb), sizeof(info));
+
+ /* TODO: Currently we only support extended_addr */
+ daddr = &info.daddr.u.extended_addr;
+ saddr = &info.saddr.u.extended_addr;
+
+ lowpan_header_compress(skb, dev, ETH_P_IPV6, daddr, saddr, skb->len);
+
+ cb->type = IEEE802154_FC_TYPE_DATA;
+
+ /* prepare wpan address data */
+ sa.mode = IEEE802154_ADDR_LONG;
+ sa.pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
+ sa.extended_addr = ieee802154_devaddr_from_raw(saddr);
+
+ /* intra-PAN communications */
+ da.pan_id = sa.pan_id;
+
+ /* if the destination address is the broadcast address, use the
+ * corresponding short address
+ */
+ if (lowpan_is_addr_broadcast((const u8 *)daddr)) {
+ da.mode = IEEE802154_ADDR_SHORT;
+ da.short_addr = cpu_to_le16(IEEE802154_ADDR_BROADCAST);
+ cb->ackreq = false;
+ } else {
+ da.mode = IEEE802154_ADDR_LONG;
+ da.extended_addr = ieee802154_devaddr_from_raw(daddr);
+ cb->ackreq = true;
+ }
+
+ return dev_hard_header(skb, lowpan_dev_info(dev)->real_dev,
+ ETH_P_IPV6, (void *)&da, (void *)&sa, 0);
+}
+
+netdev_tx_t lowpan_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ struct ieee802154_hdr wpan_hdr;
+ int max_single, ret;
+
+ pr_debug("package xmit\n");
+
+ /* We must take a copy of the skb before we modify/replace the ipv6
+ * header as the header could be used elsewhere
+ */
+ skb = skb_unshare(skb, GFP_ATOMIC);
+ if (!skb)
+ return NET_XMIT_DROP;
+
+ ret = lowpan_header(skb, dev);
+ if (ret < 0) {
+ kfree_skb(skb);
+ return NET_XMIT_DROP;
+ }
+
+ if (ieee802154_hdr_peek(skb, &wpan_hdr) < 0) {
+ kfree_skb(skb);
+ return NET_XMIT_DROP;
+ }
+
+ max_single = ieee802154_max_payload(&wpan_hdr);
+
+ if (skb_tail_pointer(skb) - skb_network_header(skb) <= max_single) {
+ skb->dev = lowpan_dev_info(dev)->real_dev;
+ return dev_queue_xmit(skb);
+ } else {
+ netdev_tx_t rc;
+
+ pr_debug("frame is too big, fragmentation is needed\n");
+ rc = lowpan_xmit_fragmented(skb, dev, &wpan_hdr);
+
+ return rc < 0 ? NET_XMIT_DROP : rc;
+ }
+}
Code Review / kvmfornfv.git / blobdiff