Signed-off-by: Jukka Rissanen <jukka.rissanen@xxxxxxxxxxxxxxx>
---
net/bluetooth/6lowpan.c | 1039 ++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 1037 insertions(+), 2 deletions(-)
diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
index 2982a4e..d33a32e 100644
--- a/net/bluetooth/6lowpan.c
+++ b/net/bluetooth/6lowpan.c
@@ -11,6 +11,20 @@
GNU General Public License for more details.
*/
+/*
+ * The compression, uncompression and IPv6 packet code
+ * is from net/ieee802154/6lowpan.c with these copyrights
+ *
+ * Copyright 2011, Siemens AG
+ * written by Alexander Smirnov <alex.bluesman.smirnov@xxxxxxxxx>
+ *
+ * Based on patches from Jon Smirl <jonsmirl@xxxxxxxxx>
+ * Copyright (c) 2011 Jon Smirl <jonsmirl@xxxxxxxxx>
+ *
+ * Jon's code is based on 6lowpan implementation for Contiki which is:
+ * Copyright (c) 2008, Swedish Institute of Computer Science.
+ */
+
#include <linux/version.h>
#include <linux/bitops.h>
#include <linux/if_arp.h>
@@ -176,8 +190,578 @@ static inline void raw_dump_table(const char *caller, char *msg,
#endif /* DEBUG */
}
-static int recv_pkt(struct sk_buff *skb, struct net_device *dev)
+static inline bool fetch_skb(struct sk_buff *skb,
+ void *data, const unsigned int len)
+{
+ if (unlikely(!pskb_may_pull(skb, len)))
+ return true;
+
+ skb_copy_from_linear_data(skb, data, len);
+ skb_pull(skb, len);
+
+ return false;
+}
+
+/*
+ * Uncompress address function for source and
+ * destination address(non-multicast).
+ *
+ * address_mode is sam value or dam value.
+ */
+static int uncompress_addr(struct sk_buff *skb,
+ struct in6_addr *ipaddr,
+ const u8 address_mode,
+ const u8 *lladdr)
+{
+ bool fail;
+
+ switch (address_mode) {
+ case LOWPAN_IPHC_ADDR_00:
+ /* for global link addresses */
+ fail = fetch_skb(skb, ipaddr->s6_addr, 16);
+ break;
+ case LOWPAN_IPHC_ADDR_01:
+ /* fe:80::XXXX:XXXX:XXXX:XXXX */
+ ipaddr->s6_addr[0] = 0xFE;
+ ipaddr->s6_addr[1] = 0x80;
+ fail = fetch_skb(skb, &ipaddr->s6_addr[8], 8);
+ break;
+ case LOWPAN_IPHC_ADDR_02:
+ /* fe:80::ff:fe00:XXXX */
+ ipaddr->s6_addr[0] = 0xFE;
+ ipaddr->s6_addr[1] = 0x80;
+ ipaddr->s6_addr[11] = 0xFF;
+ ipaddr->s6_addr[12] = 0xFE;
+ fail = fetch_skb(skb, &ipaddr->s6_addr[14], 2);
+ break;
+ case LOWPAN_IPHC_ADDR_03:
+ fail = false;
+ /* XXX: support only normal addr (IEEE802154_ADDR_LONG) atm */
+
+ /* fe:80::XXXX:XXXX:XXXX:XXXX
+ * \_________________/
+ * hwaddr
+ */
+ ipaddr->s6_addr[0] = 0xFE;
+ ipaddr->s6_addr[1] = 0x80;
+ memcpy(&ipaddr->s6_addr[8], lladdr, EUI64_ADDR_LEN);
+ break;
+ default:
+ pr_debug("Invalid address mode value: 0x%x\n", address_mode);
+ return -EINVAL;
+ }
+
+ if (fail) {
+ pr_debug("Failed to fetch skb data\n");
+ return -EIO;
+ }
+
+ raw_dump_inline(NULL, "Reconstructed ipv6 addr is",
+ ipaddr->s6_addr, 16);
+
+ return 0;
+}
+
+/*
+ * Uncompress address function for source context
+ * based address(non-multicast).
+ */
+static int uncompress_context_based_src_addr(struct sk_buff *skb,
+ struct in6_addr *ipaddr,
+ const u8 sam)
+{
+ switch (sam) {
+ case LOWPAN_IPHC_ADDR_00:
+ /* unspec address ::
+ * Do nothing, address is already ::
+ */
+ break;
+ case LOWPAN_IPHC_ADDR_01:
+ /* TODO */
+ case LOWPAN_IPHC_ADDR_02:
+ /* TODO */
+ case LOWPAN_IPHC_ADDR_03:
+ /* TODO */
+ netdev_warn(skb->dev, "SAM value 0x%x not supported\n", sam);
+ return -EINVAL;
+ default:
+ pr_debug("Invalid sam value: 0x%x\n", sam);
+ return -EINVAL;
+ }
+
+ raw_dump_inline(NULL,
+ "Reconstructed context based ipv6 src addr is",
+ ipaddr->s6_addr, 16);
+
+ return 0;
+}
+
+/*
+ * This func is called when the packet from BT LE device
+ * needs to be sent upper layers.
+ */
+static int give_skb_to_upper(struct sk_buff *skb,
+ struct net_device *dev)
+{
+ struct sk_buff *skb_cp;
+ int ret = NET_RX_SUCCESS;
+
+ skb_cp = skb_copy(skb, GFP_ATOMIC);
+ if (!skb_cp) {
+ ret = -ENOMEM;
+ } else {
+ ret = netif_rx(skb_cp);
+
+ BT_DBG("receive skb %d", ret);
+ if (ret < 0)
+ ret = NET_RX_DROP;
+ }
+
+ return ret;
+}
+
+static inline int fetch_skb_u8(struct sk_buff *skb, u8 *val)
+{
+ if (unlikely(!pskb_may_pull(skb, 1)))
+ return -EINVAL;
+
+ *val = skb->data[0];
+ skb_pull(skb, 1);
+
+ return 0;
+}
+
+static inline int fetch_skb_u16(struct sk_buff *skb, u16 *val)
+{
+ if (unlikely(!pskb_may_pull(skb, 2)))
+ return -EINVAL;
+
+ *val = (skb->data[0] << 8) | skb->data[1];
+ skb_pull(skb, 2);
+
+ return 0;
+}
+
+static int skb_deliver(struct sk_buff *skb, struct ipv6hdr *hdr,
+ struct net_device *dev)
+{
+ struct sk_buff *new;
+ int stat;
+
+ new = skb_copy_expand(skb, sizeof(struct ipv6hdr), skb_tailroom(skb),
+ GFP_ATOMIC);
+ kfree_skb(skb);
+
+ if (!new)
+ return -ENOMEM;
+
+ skb_push(new, sizeof(struct ipv6hdr));
+ skb_reset_network_header(new);
+ skb_copy_to_linear_data(new, hdr, sizeof(struct ipv6hdr));
+
+ new->protocol = htons(ETH_P_IPV6);
+ new->pkt_type = PACKET_HOST;
+ new->dev = dev;
+
+ raw_dump_table(__func__,
+ "raw skb data dump before receiving",
+ new->data, new->len);
+
+ stat = give_skb_to_upper(new, dev);
+
+ kfree_skb(new);
+
+ return stat;
+}
+
+/* Uncompress function for multicast destination address,
+ * when M bit is set.
+ */
+static int
+lowpan_uncompress_multicast_daddr(struct sk_buff *skb,
+ struct in6_addr *ipaddr,
+ const u8 dam)
+{
+ bool fail;
+
+ switch (dam) {
+ case LOWPAN_IPHC_DAM_00:
+ /* 00: 128 bits. The full address
+ * is carried in-line.
+ */
+ fail = fetch_skb(skb, ipaddr->s6_addr, 16);
+ break;
+ case LOWPAN_IPHC_DAM_01:
+ /* 01: 48 bits. The address takes
+ * the form ffXX::00XX:XXXX:XXXX.
+ */
+ ipaddr->s6_addr[0] = 0xFF;
+ fail = fetch_skb(skb, &ipaddr->s6_addr[1], 1);
+ fail |= fetch_skb(skb, &ipaddr->s6_addr[11], 5);
+ break;
+ case LOWPAN_IPHC_DAM_10:
+ /* 10: 32 bits. The address takes
+ * the form ffXX::00XX:XXXX.
+ */
+ ipaddr->s6_addr[0] = 0xFF;
+ fail = fetch_skb(skb, &ipaddr->s6_addr[1], 1);
+ fail |= fetch_skb(skb, &ipaddr->s6_addr[13], 3);
+ break;
+ case LOWPAN_IPHC_DAM_11:
+ /* 11: 8 bits. The address takes
+ * the form ff02::00XX.
+ */
+ ipaddr->s6_addr[0] = 0xFF;
+ ipaddr->s6_addr[1] = 0x02;
+ fail = fetch_skb(skb, &ipaddr->s6_addr[15], 1);
+ break;
+ default:
+ pr_debug("DAM value has a wrong value: 0x%x\n", dam);
+ return -EINVAL;
+ }
+
+ if (fail) {
+ pr_debug("Failed to fetch skb data\n");
+ return -EIO;
+ }
+
+ raw_dump_inline(NULL,
+ "Reconstructed ipv6 multicast addr is",
+ ipaddr->s6_addr, 16);
+
+ return 0;
+}
+
+static int
+uncompress_udp_header(struct sk_buff *skb, struct udphdr *uh)
+{
+ u8 tmp;
+
+ if (!uh)
+ goto err;
+
+ if (fetch_skb_u8(skb, &tmp))
+ goto err;
+
+ if ((tmp & LOWPAN_NHC_UDP_MASK) == LOWPAN_NHC_UDP_ID) {
+ pr_debug("UDP header uncompression\n");
+ switch (tmp & LOWPAN_NHC_UDP_CS_P_11) {
+ case LOWPAN_NHC_UDP_CS_P_00:
+ memcpy(&uh->source, &skb->data[0], 2);
+ memcpy(&uh->dest, &skb->data[2], 2);
+ skb_pull(skb, 4);
+ break;
+ case LOWPAN_NHC_UDP_CS_P_01:
+ memcpy(&uh->source, &skb->data[0], 2);
+ uh->dest =
+ skb->data[2] + LOWPAN_NHC_UDP_8BIT_PORT;
+ skb_pull(skb, 3);
+ break;
+ case LOWPAN_NHC_UDP_CS_P_10:
+ uh->source = skb->data[0] + LOWPAN_NHC_UDP_8BIT_PORT;
+ memcpy(&uh->dest, &skb->data[1], 2);
+ skb_pull(skb, 3);
+ break;
+ case LOWPAN_NHC_UDP_CS_P_11:
+ uh->source =
+ LOWPAN_NHC_UDP_4BIT_PORT + (skb->data[0] >> 4);
+ uh->dest =
+ LOWPAN_NHC_UDP_4BIT_PORT + (skb->data[0] & 0x0f);
+ skb_pull(skb, 1);
+ break;
+ default:
+ pr_debug("ERROR: unknown UDP format\n");
+ goto err;
+ break;
+ }
+
+ pr_debug("uncompressed UDP ports: src = %d, dst = %d\n",
+ uh->source, uh->dest);
+
+ /* copy checksum */
+ memcpy(&uh->check, &skb->data[0], 2);
+ skb_pull(skb, 2);
+
+ /*
+ * UDP lenght needs to be infered from the lower layers
+ * here, we obtain the hint from the remaining size of the
+ * frame
+ */
+ uh->len = htons(skb->len + sizeof(struct udphdr));
+ pr_debug("uncompressed UDP length: src = %d", uh->len);
+ } else {
+ pr_debug("ERROR: unsupported NH format\n");
+ goto err;
+ }
+
+ return 0;
+err:
+ return -EINVAL;
+}
+
+/* TTL uncompression values */
+static const u8 lowpan_ttl_values[] = { 0, 1, 64, 255 };
+
+static int process_data(struct sk_buff *skb, struct net_device *dev,
+ struct l2cap_conn *conn)
+{
+ struct ipv6hdr hdr = {};
+ u8 tmp, iphc0, iphc1, num_context = 0;
+ const u8 *_saddr = NULL, *_daddr = NULL;
+ struct lowpan_info *info;
+ struct peer *peer;
+ int err;
+
+ raw_dump_table(__func__, "raw skb data dump uncompressed",
+ skb->data, skb->len);
+
+ /* at least two bytes will be used for the encoding */
+ if (skb->len < 2)
+ goto drop;
+
+ if (fetch_skb_u8(skb, &iphc0))
+ goto drop;
+
+ info = lowpan_info(dev);
+
+ if (fetch_skb_u8(skb, &iphc1))
+ goto drop;
+
+ write_lock(&devices_lock);
+ peer = peer_lookup_conn(info, conn);
+ write_unlock(&devices_lock);
+ if (!peer)
+ goto drop;
+
+ _saddr = peer->eui64_addr;
+ _daddr = info->net->dev_addr;
+
+ /* another if the CID flag is set */
+ if (iphc1 & LOWPAN_IPHC_CID) {
+ pr_debug("CID flag is set, increase header with one\n");
+ if (fetch_skb_u8(skb, &num_context))
+ goto drop;
+ }
+
+ hdr.version = 6;
+
+ /* Traffic Class and Flow Label */
+ switch ((iphc0 & LOWPAN_IPHC_TF) >> 3) {
+ /*
+ * Traffic Class and FLow Label carried in-line
+ * ECN + DSCP + 4-bit Pad + Flow Label (4 bytes)
+ */
+ case 0: /* 00b */
+ if (fetch_skb_u8(skb, &tmp))
+ goto drop;
+
+ memcpy(&hdr.flow_lbl, &skb->data[0], 3);
+ skb_pull(skb, 3);
+ hdr.priority = ((tmp >> 2) & 0x0f);
+ hdr.flow_lbl[0] = ((tmp >> 2) & 0x30) | (tmp << 6) |
+ (hdr.flow_lbl[0] & 0x0f);
+ break;
+ /*
+ * Traffic class carried in-line
+ * ECN + DSCP (1 byte), Flow Label is elided
+ */
+ case 1: /* 10b */
+ if (fetch_skb_u8(skb, &tmp))
+ goto drop;
+
+ hdr.priority = ((tmp >> 2) & 0x0f);
+ hdr.flow_lbl[0] = ((tmp << 6) & 0xC0) | ((tmp >> 2) & 0x30);
+ break;
+ /*
+ * Flow Label carried in-line
+ * ECN + 2-bit Pad + Flow Label (3 bytes), DSCP is elided
+ */
+ case 2: /* 01b */
+ if (fetch_skb_u8(skb, &tmp))
+ goto drop;
+
+ hdr.flow_lbl[0] = (skb->data[0] & 0x0F) | ((tmp >> 2) & 0x30);
+ memcpy(&hdr.flow_lbl[1], &skb->data[0], 2);
+ skb_pull(skb, 2);
+ break;
+ /* Traffic Class and Flow Label are elided */
+ case 3: /* 11b */
+ break;
+ default:
+ break;
+ }
+
+ /* Next Header */
+ if ((iphc0 & LOWPAN_IPHC_NH_C) == 0) {
+ /* Next header is carried inline */
+ if (fetch_skb_u8(skb, &(hdr.nexthdr)))
+ goto drop;
+
+ pr_debug("NH flag is set, next header carried inline: %02x\n",
+ hdr.nexthdr);
+ }
+
+ /* Hop Limit */
+ if ((iphc0 & 0x03) != LOWPAN_IPHC_TTL_I)
+ hdr.hop_limit = lowpan_ttl_values[iphc0 & 0x03];
+ else {
+ if (fetch_skb_u8(skb, &(hdr.hop_limit)))
+ goto drop;
+ }
+
+ /* Extract SAM to the tmp variable */
+ tmp = ((iphc1 & LOWPAN_IPHC_SAM) >> LOWPAN_IPHC_SAM_BIT) & 0x03;
+
+ if (iphc1 & LOWPAN_IPHC_SAC) {
+ /* Source address context based uncompression */
+ pr_debug("SAC bit is set. Handle context based source address.\n");
+ err = uncompress_context_based_src_addr(
+ skb, &hdr.saddr, tmp);
+ } else {
+ /* Source address uncompression */
+ pr_debug("source address stateless compression\n");
+ err = uncompress_addr(skb, &hdr.saddr, tmp, _saddr);
+ }
+
+ /* Check on error of previous branch */
+ if (err)
+ goto drop;
+
+ /* Extract DAM to the tmp variable */
+ tmp = ((iphc1 & LOWPAN_IPHC_DAM_11) >> LOWPAN_IPHC_DAM_BIT) & 0x03;
+
+ /* check for Multicast Compression */
+ if (iphc1 & LOWPAN_IPHC_M) {
+ if (iphc1 & LOWPAN_IPHC_DAC) {
+ pr_debug("dest: context-based mcast compression\n");
+ /* TODO: implement this */
+ } else {
+ err = lowpan_uncompress_multicast_daddr(
+ skb, &hdr.daddr, tmp);
+ if (err)
+ goto drop;
+ }
+ } else {
+ pr_debug("dest: stateless compression\n");
+ err = uncompress_addr(skb, &hdr.daddr, tmp, _daddr);
+ if (err)
+ goto drop;
+ }
+
+ /* UDP data uncompression */
+ if (iphc0 & LOWPAN_IPHC_NH_C) {
+ struct udphdr uh;
+ struct sk_buff *new;
+ if (uncompress_udp_header(skb, &uh))
+ goto drop;
+
+ /*
+ * replace the compressed UDP head by the uncompressed UDP
+ * header
+ */
+ new = skb_copy_expand(skb, sizeof(struct udphdr),
+ skb_tailroom(skb), GFP_ATOMIC);
+ kfree_skb(skb);
+
+ if (!new)
+ return -ENOMEM;
+
+ skb = new;
+
+ skb_push(skb, sizeof(struct udphdr));
+ skb_reset_transport_header(skb);
+ skb_copy_to_linear_data(skb, &uh, sizeof(struct udphdr));
+
+ raw_dump_table(__func__, "raw UDP header dump",
+ (u8 *)&uh, sizeof(uh));
+
+ hdr.nexthdr = UIP_PROTO_UDP;
+ }
+
+ hdr.payload_len = htons(skb->len);
+
+ pr_debug("skb headroom size = %d, data length = %d\n",
+ skb_headroom(skb), skb->len);
+
+ pr_debug("IPv6 header dump:\n\tversion = %d\n\tlength = %d\n\t"
+ "nexthdr = 0x%02x\n\thop_lim = %d\n\tdest = %pI6c\n",
+ hdr.version, ntohs(hdr.payload_len), hdr.nexthdr,
+ hdr.hop_limit, &hdr.daddr);
+
+ raw_dump_table(__func__, "raw header dump", (u8 *)&hdr,
+ sizeof(hdr));
+
+ return skb_deliver(skb, &hdr, dev);
+
+drop:
+ kfree_skb(skb);
+ return -EINVAL;
+}
+
+static int recv_pkt(struct sk_buff *skb, struct net_device *dev,
+ struct l2cap_conn *conn)
{
+ struct sk_buff *local_skb;
+
+ if (!netif_running(dev))
+ goto drop;
+
+ if (dev->type != ARPHRD_RAWIP)
+ goto drop;
+
+ raw_dump_table(__func__, "raw recv dump", skb->head,
+ skb->len);
+
+ /* check that it's our buffer */
+ if (skb->data[0] == LOWPAN_DISPATCH_IPV6) {
+ /* Copy the packet so that the IPv6 header is
+ * properly aligned.
+ */
+ local_skb = skb_copy_expand(skb, NET_SKB_PAD - 1,
+ skb_tailroom(skb), GFP_ATOMIC);
+ if (!local_skb)
+ goto drop;
+
+ local_skb->protocol = htons(ETH_P_IPV6);
+ local_skb->pkt_type = PACKET_HOST;
+
+ skb_reset_network_header(local_skb);
+ skb_set_transport_header(local_skb, sizeof(struct ipv6hdr));
+
+ if (give_skb_to_upper(local_skb,
+ dev) != NET_RX_SUCCESS) {
+ kfree_skb(local_skb);
+ goto drop;
+ }
+
+ dev->stats.rx_bytes += skb->len;
+ dev->stats.rx_packets++;
+
+ kfree_skb(local_skb);
+ kfree_skb(skb);
+ } else {
+ switch (skb->data[0] & 0xe0) {
+ case LOWPAN_DISPATCH_IPHC: /* ipv6 datagram */
+ local_skb = skb_clone(skb, GFP_ATOMIC);
+ if (!local_skb)
+ goto drop;
+ if (process_data(local_skb, dev, conn)
+ != NET_RX_SUCCESS)
+ goto drop;
+
+ dev->stats.rx_bytes += skb->len;
+ dev->stats.rx_packets++;
+
+ kfree_skb(skb);
+ break;
+ default:
+ break;
+ }
+ }
+
+ return NET_RX_SUCCESS;
+
+drop:
kfree_skb(skb);
return NET_RX_DROP;
}
@@ -206,19 +790,465 @@ static void do_send(struct l2cap_conn *conn, struct sk_buff *skb)
BT_DBG("conn %p, skb %p len %d priority %u", conn, skb, skb->len,
skb->priority);
+ hci_send_acl(conn->hchan, skb, ACL_START);
return;
}
+static inline int skbuff_copy(void *msg, int len,
+ int count, int mtu,
+ struct sk_buff *skb,
+ struct net_device *dev)
+{
+ struct sk_buff **frag;
+ int sent = 0;
+
+ memcpy(skb_put(skb, count), msg, count);
+
+ sent += count;
+ msg += count;
+ len -= count;
+
+ dev->stats.tx_bytes += count;
+ dev->stats.tx_packets++;
+
+ raw_dump_table(__func__, "Sending", skb->data, skb->len);
+
+ /* Continuation fragments (no L2CAP header) */
+ frag = &skb_shinfo(skb)->frag_list;
+ while (len > 0) {
+ struct sk_buff *tmp;
+
+ count = min_t(unsigned int, mtu, len);
+
+ tmp = bt_skb_alloc(count, GFP_KERNEL);
+ if (IS_ERR(tmp))
+ return PTR_ERR(tmp);
+
+ *frag = tmp;
+
+ memcpy(skb_put(*frag, count), msg, count);
+
+ raw_dump_table(__func__, "Sending fragment",
+ (*frag)->data, count);
+
+ (*frag)->priority = skb->priority;
+
+ sent += count;
+ msg += count;
+ len -= count;
+
+ skb->len += (*frag)->len;
+ skb->data_len += (*frag)->len;
+
+ frag = &(*frag)->next;
+
+ dev->stats.tx_bytes += count;
+ dev->stats.tx_packets++;
+ }
+
+ return sent;
+}
+
+static struct sk_buff *create_pdu(struct l2cap_conn *conn,
+ void *msg, size_t len,
+ u32 priority,
+ struct net_device *dev)
+{
+ struct sk_buff *skb;
+ int err, count;
+ struct l2cap_hdr *lh;
+
+ if (conn->mtu > (L2CAP_LE_MIN_MTU + L2CAP_HDR_SIZE))
+ /* XXX: This should be not needed and atm is only used for
+ * testing purposes */
+ conn->mtu = L2CAP_LE_MIN_MTU + L2CAP_HDR_SIZE;
+
+ count = min_t(unsigned int, (conn->mtu - L2CAP_HDR_SIZE), len);
+
+ BT_DBG("conn %p len %zu mtu %d count %d", conn, len, conn->mtu, count);
+
+ skb = bt_skb_alloc(count + L2CAP_HDR_SIZE, GFP_KERNEL);
+ if (IS_ERR(skb))
+ return skb;
+
+ skb->priority = priority;
+
+ lh = (struct l2cap_hdr *)skb_put(skb, L2CAP_HDR_SIZE);
+ lh->cid = cpu_to_le16(L2CAP_FC_6LOWPAN);
+ lh->len = cpu_to_le16(len);
+
+ err = skbuff_copy(msg, len, count, conn->mtu, skb, dev);
+ if (unlikely(err < 0)) {
+ kfree_skb(skb);
+ BT_DBG("skbuff copy %d failed", err);
+ return ERR_PTR(err);
+ }
+
+ return skb;
+}
+
static int conn_send(struct l2cap_conn *conn,
void *msg, size_t len, u32 priority,
struct net_device *dev)
{
- struct sk_buff *skb = {0};
+ struct sk_buff *skb;
+
+ skb = create_pdu(conn, msg, len, priority, dev);
+ if (IS_ERR(skb))
+ return -EINVAL;
do_send(conn, skb);
return 0;
}
+static u8 lowpan_compress_addr_64(u8 **hc06_ptr, u8 shift,
+ const struct in6_addr *ipaddr,
+ const unsigned char *lladdr)
+{
+ u8 val = 0;
+
+ if (is_addr_mac_addr_based(ipaddr, lladdr))
+ val = 3; /* 0-bits */
+ else if (lowpan_is_iid_16_bit_compressable(ipaddr)) {
+ /* compress IID to 16 bits xxxx::XXXX */
+ memcpy(*hc06_ptr, &ipaddr->s6_addr16[7], 2);
+ *hc06_ptr += 2;
+ val = 2; /* 16-bits */
+ } else {
+ /* do not compress IID => xxxx::IID */
+ memcpy(*hc06_ptr, &ipaddr->s6_addr16[4], 8);
+ *hc06_ptr += 8;
+ val = 1; /* 64-bits */
+ }
+
+ return rol8(val, shift);
+}
+
+static void compress_udp_header(u8 **hc06_ptr, struct sk_buff *skb)
+{
+ struct udphdr *uh = udp_hdr(skb);
+
+ if (((uh->source & LOWPAN_NHC_UDP_4BIT_MASK) ==
+ LOWPAN_NHC_UDP_4BIT_PORT) &&
+ ((uh->dest & LOWPAN_NHC_UDP_4BIT_MASK) ==
+ LOWPAN_NHC_UDP_4BIT_PORT)) {
+ pr_debug("UDP header: both ports compression to 4 bits\n");
+ **hc06_ptr = LOWPAN_NHC_UDP_CS_P_11;
+ **(hc06_ptr + 1) = /* subtraction is faster */
+ (u8)((uh->dest - LOWPAN_NHC_UDP_4BIT_PORT) +
+ ((uh->source & LOWPAN_NHC_UDP_4BIT_PORT) << 4));
+ *hc06_ptr += 2;
+ } else if ((uh->dest & LOWPAN_NHC_UDP_8BIT_MASK) ==
+ LOWPAN_NHC_UDP_8BIT_PORT) {
+ pr_debug("UDP header: remove 8 bits of dest\n");
+ **hc06_ptr = LOWPAN_NHC_UDP_CS_P_01;
+ memcpy(*hc06_ptr + 1, &uh->source, 2);
+ **(hc06_ptr + 3) = (u8)(uh->dest - LOWPAN_NHC_UDP_8BIT_PORT);
+ *hc06_ptr += 4;
+ } else if ((uh->source & LOWPAN_NHC_UDP_8BIT_MASK) ==
+ LOWPAN_NHC_UDP_8BIT_PORT) {
+ pr_debug("UDP header: remove 8 bits of source\n");
+ **hc06_ptr = LOWPAN_NHC_UDP_CS_P_10;
+ memcpy(*hc06_ptr + 1, &uh->dest, 2);
+ **(hc06_ptr + 3) = (u8)(uh->source - LOWPAN_NHC_UDP_8BIT_PORT);
+ *hc06_ptr += 4;
+ } else {
+ pr_debug("UDP header: can't compress\n");
+ **hc06_ptr = LOWPAN_NHC_UDP_CS_P_00;
+ memcpy(*hc06_ptr + 1, &uh->source, 2);
+ memcpy(*hc06_ptr + 3, &uh->dest, 2);
+ *hc06_ptr += 5;
+ }
+
+ /* checksum is always inline */
+ memcpy(*hc06_ptr, &uh->check, 2);
+ *hc06_ptr += 2;
+
+ /* skip the UDP header */
+ skb_pull(skb, sizeof(struct udphdr));
+}
+
+static inline int lowpan_fetch_skb_u8(struct sk_buff *skb, u8 *val)
+{
+ if (unlikely(!pskb_may_pull(skb, 1)))
+ return -EINVAL;
+
+ *val = skb->data[0];
+ skb_pull(skb, 1);
+
+ return 0;
+}
+
+static inline int lowpan_fetch_skb_u16(struct sk_buff *skb, u16 *val)
+{
+ if (unlikely(!pskb_may_pull(skb, 2)))
+ return -EINVAL;
+
+ *val = (skb->data[0] << 8) | skb->data[1];
+ skb_pull(skb, 2);
+
+ return 0;
+}
+
+static void get_dest_bdaddr(struct in6_addr *ip6_daddr,
+ bdaddr_t *addr, u8 *addr_type)
+{
+ u8 *eui64;
+
+ eui64 = ip6_daddr->s6_addr + 8;
+
+ addr->b[0] = eui64[7];
+ addr->b[1] = eui64[6];
+ addr->b[2] = eui64[5];
+ addr->b[3] = eui64[2];
+ addr->b[4] = eui64[1];
+ addr->b[5] = eui64[0];
+
+ addr->b[5] ^= 2;
+
+ /* Set universal/local bit to 0 */
+ if (addr->b[5] & 1) {
+ addr->b[5] &= ~1;
+ *addr_type = BDADDR_LE_PUBLIC;
+ } else
+ *addr_type = BDADDR_LE_RANDOM;
+}
+
+static int header_create(struct sk_buff *skb, struct net_device *dev,
+ unsigned short type, const void *_daddr,
+ const void *_saddr, unsigned int len)
+{
+ u8 tmp, iphc0, iphc1, *hc06_ptr;
+ struct lowpan_info *info;
+ struct peer *peer;
+ struct ipv6hdr *hdr;
+ bdaddr_t addr, *any = BDADDR_ANY;
+ u8 *saddr, *daddr = any->b;
+ u8 addr_type;
+ u8 head[100];
+
+ if (type != ETH_P_IPV6)
+ return -EINVAL;
+
+ hdr = ipv6_hdr(skb);
+ hc06_ptr = head + 2;
+
+ pr_debug("IPv6 header dump:\n\tversion = %d\n\tlength = %d\n"
+ "\tnexthdr = 0x%02x\n\thop_lim = %d\n\tdest = %pI6c\n",
+ hdr->version, ntohs(hdr->payload_len), hdr->nexthdr,
+ hdr->hop_limit, &hdr->daddr);
+
+ raw_dump_table(__func__, "raw skb network header dump",
+ skb_network_header(skb), sizeof(struct ipv6hdr));
+
+ info = lowpan_info(dev);
+
+ if (ipv6_addr_is_multicast(&hdr->daddr)) {
+ memcpy(&lowpan_cb(skb)->addr, &hdr->daddr,
+ sizeof(struct in6_addr));
+ lowpan_cb(skb)->conn = NULL;
+ } else {
+ /*
+ * Get destination BT device from skb.
+ * If there is no such peer then discard the packet.
+ */
+ get_dest_bdaddr(&hdr->daddr, &addr, &addr_type);
+
+ BT_DBG("dest addr %pMR type %d", &addr, addr_type);
+
+ write_lock(&devices_lock);
+ peer = peer_lookup_ba(info, addr_type, &addr);
+ write_unlock(&devices_lock);
+
+ if (!peer) {
+ BT_DBG("no such peer %pMR found", &addr);
+ return -ENOENT;
+ }
+
+ daddr = peer->eui64_addr;
+
+ memcpy(&lowpan_cb(skb)->addr, &hdr->daddr,
+ sizeof(struct in6_addr));
+ lowpan_cb(skb)->conn = peer->conn;
+ }
+
+ saddr = info->net->dev_addr;
+
+ raw_dump_inline(__func__, "saddr",
+ (unsigned char *)saddr, 8);
+
+ /*
+ * As we copy some bit-length fields, in the IPHC encoding bytes,
+ * we sometimes use |=
+ * If the field is 0, and the current bit value in memory is 1,
+ * this does not work. We therefore reset the IPHC encoding here
+ */
+ iphc0 = LOWPAN_DISPATCH_IPHC;
+ iphc1 = 0;
+
+ /* TODO: context lookup */
+
+ raw_dump_inline(__func__, "daddr",
+ (unsigned char *)daddr, 8);
+
+ raw_dump_table(__func__,
+ "sending raw skb network uncompressed packet",
+ skb->data, skb->len);
+
+ /*
+ * Traffic class, flow label
+ * If flow label is 0, compress it. If traffic class is 0, compress it
+ * We have to process both in the same time as the offset of traffic
+ * class depends on the presence of version and flow label
+ */
+
+ /* hc06 format of TC is ECN | DSCP , original one is DSCP | ECN */
+ tmp = (hdr->priority << 4) | (hdr->flow_lbl[0] >> 4);
+ tmp = ((tmp & 0x03) << 6) | (tmp >> 2);
+
+ if (((hdr->flow_lbl[0] & 0x0F) == 0) &&
+ (hdr->flow_lbl[1] == 0) && (hdr->flow_lbl[2] == 0)) {
+ /* flow label can be compressed */
+ iphc0 |= LOWPAN_IPHC_FL_C;
+ if ((hdr->priority == 0) &&
+ ((hdr->flow_lbl[0] & 0xF0) == 0)) {
+ /* compress (elide) all */
+ iphc0 |= LOWPAN_IPHC_TC_C;
+ } else {
+ /* compress only the flow label */
+ *hc06_ptr = tmp;
+ hc06_ptr += 1;
+ }
+ } else {
+ /* Flow label cannot be compressed */
+ if ((hdr->priority == 0) &&
+ ((hdr->flow_lbl[0] & 0xF0) == 0)) {
+ /* compress only traffic class */
+ iphc0 |= LOWPAN_IPHC_TC_C;
+ *hc06_ptr = (tmp & 0xc0) | (hdr->flow_lbl[0] & 0x0F);
+ memcpy(hc06_ptr + 1, &hdr->flow_lbl[1], 2);
+ hc06_ptr += 3;
+ } else {
+ /* compress nothing */
+ memcpy(hc06_ptr, &hdr, 4);
+ /* replace the top byte with new ECN | DSCP format */
+ *hc06_ptr = tmp;
+ hc06_ptr += 4;
+ }
+ }
+
+ /* NOTE: payload length is always compressed */
+
+ /* Next Header is compress if UDP */
+ if (hdr->nexthdr == UIP_PROTO_UDP)
+ iphc0 |= LOWPAN_IPHC_NH_C;
+
+ if ((iphc0 & LOWPAN_IPHC_NH_C) == 0) {
+ *hc06_ptr = hdr->nexthdr;
+ hc06_ptr += 1;
+ }
+
+ /*
+ * Hop limit
+ * if 1: compress, encoding is 01
+ * if 64: compress, encoding is 10
+ * if 255: compress, encoding is 11
+ * else do not compress
+ */
+ switch (hdr->hop_limit) {
+ case 1:
+ iphc0 |= LOWPAN_IPHC_TTL_1;
+ break;
+ case 64:
+ iphc0 |= LOWPAN_IPHC_TTL_64;
+ break;
+ case 255:
+ iphc0 |= LOWPAN_IPHC_TTL_255;
+ break;
+ default:
+ *hc06_ptr = hdr->hop_limit;
+ hc06_ptr += 1;
+ break;
+ }
+
+ /* source address compression */
+ if (is_addr_unspecified(&hdr->saddr)) {
+ pr_debug("source address is unspecified, setting SAC\n");
+ iphc1 |= LOWPAN_IPHC_SAC;
+ /* TODO: context lookup */
+ } else if (is_addr_link_local(&hdr->saddr)) {
+ pr_debug("source address is link-local\n");
+ iphc1 |= lowpan_compress_addr_64(&hc06_ptr,
+ LOWPAN_IPHC_SAM_BIT, &hdr->saddr, saddr);
+ } else {
+ pr_debug("send the full source address\n");
+ memcpy(hc06_ptr, &hdr->saddr.s6_addr16[0], 16);
+ hc06_ptr += 16;
+ }
+
+ /* destination address compression */
+ if (is_addr_mcast(&hdr->daddr)) {
+ pr_debug("destination address is multicast: ");
+ iphc1 |= LOWPAN_IPHC_M;
+ if (lowpan_is_mcast_addr_compressable8(&hdr->daddr)) {
+ pr_debug("compressed to 1 octet\n");
+ iphc1 |= LOWPAN_IPHC_DAM_11;
+ /* use last byte */
+ *hc06_ptr = hdr->daddr.s6_addr[15];
+ hc06_ptr += 1;
+ } else if (lowpan_is_mcast_addr_compressable32(&hdr->daddr)) {
+ pr_debug("compressed to 4 octets\n");
+ iphc1 |= LOWPAN_IPHC_DAM_10;
+ /* second byte + the last three */
+ *hc06_ptr = hdr->daddr.s6_addr[1];
+ memcpy(hc06_ptr + 1, &hdr->daddr.s6_addr[13], 3);
+ hc06_ptr += 4;
+ } else if (lowpan_is_mcast_addr_compressable48(&hdr->daddr)) {
+ pr_debug("compressed to 6 octets\n");
+ iphc1 |= LOWPAN_IPHC_DAM_01;
+ /* second byte + the last five */
+ *hc06_ptr = hdr->daddr.s6_addr[1];
+ memcpy(hc06_ptr + 1, &hdr->daddr.s6_addr[11], 5);
+ hc06_ptr += 6;
+ } else {
+ pr_debug("using full address\n");
+ iphc1 |= LOWPAN_IPHC_DAM_00;
+ memcpy(hc06_ptr, &hdr->daddr.s6_addr[0], 16);
+ hc06_ptr += 16;
+ }
+ } else {
+ /* TODO: context lookup */
+ if (is_addr_link_local(&hdr->daddr)) {
+ pr_debug("dest address is unicast and link-local\n");
+ iphc1 |= lowpan_compress_addr_64(&hc06_ptr,
+ LOWPAN_IPHC_DAM_BIT, &hdr->daddr, daddr);
+ } else {
+ pr_debug("dest address is unicast: using full one\n");
+ memcpy(hc06_ptr, &hdr->daddr.s6_addr16[0], 16);
+ hc06_ptr += 16;
+ }
+ }
+
+ /* UDP header compression */
+ if (hdr->nexthdr == UIP_PROTO_UDP)
+ compress_udp_header(&hc06_ptr, skb);
+
+ head[0] = iphc0;
+ head[1] = iphc1;
+
+ skb_pull(skb, sizeof(struct ipv6hdr));
+
+ memcpy(skb_push(skb, hc06_ptr - head), head, hc06_ptr - head);
+
+ BT_DBG("header len %d skb %u", (int)(hc06_ptr - head), skb->len);
+
+ skb_reset_network_header(skb);
+
+ raw_dump_table(__func__, "raw skb data dump compressed",
+ skb->data, skb->len);
+ return 0;
+}
+
/* Packet to BT LE device */
static int send_pkt(struct l2cap_conn *conn, const void *saddr,
const void *daddr, struct sk_buff *skb,
@@ -309,6 +1339,10 @@ static const struct net_device_ops netdev_ops = {
.ndo_start_xmit = xmit,
};
+static struct header_ops header_ops = {
+ .create = header_create,
+};
+
static void netdev_setup(struct net_device *dev)
{
dev->addr_len = EUI64_ADDR_LEN;
@@ -322,6 +1356,7 @@ static void netdev_setup(struct net_device *dev)
dev->watchdog_timeo = 0;
dev->netdev_ops = &netdev_ops;
+ dev->header_ops = &header_ops;
dev->destructor = free_netdev;
}
--
1.8.3.1
--
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