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Posted to commits@mynewt.apache.org by ma...@apache.org on 2016/09/30 00:30:52 UTC

[09/51] [abbrv] [partial] incubator-mynewt-core git commit: net/ip/lwip_base; LwIP.

http://git-wip-us.apache.org/repos/asf/incubator-mynewt-core/blob/f5a0f2a0/net/ip/lwip_base/src/netif/lowpan6.c
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diff --git a/net/ip/lwip_base/src/netif/lowpan6.c b/net/ip/lwip_base/src/netif/lowpan6.c
new file mode 100644
index 0000000..407848c
--- /dev/null
+++ b/net/ip/lwip_base/src/netif/lowpan6.c
@@ -0,0 +1,1204 @@
+/**
+  * @file
+ *
+ * 6LowPAN output for IPv6. Uses ND tables for link-layer addressing. Fragments packets to 6LowPAN units.
+ */
+
+/*
+ * Copyright (c) 2015 Inico Technologies Ltd.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Ivan Delamer <de...@inicotech.com>
+ *
+ *
+ * Please coordinate changes and requests with Ivan Delamer
+ * <de...@inicotech.com>
+ */
+
+/**
+ * @defgroup sixlowpan 6LowPAN netif
+ * @ingroup addons
+ * 6LowPAN netif implementation
+ */
+
+#include "netif/lowpan6.h"
+
+#if LWIP_IPV6 && LWIP_6LOWPAN
+
+#include "lwip/ip.h"
+#include "lwip/pbuf.h"
+#include "lwip/ip_addr.h"
+#include "lwip/netif.h"
+#include "lwip/nd6.h"
+#include "lwip/mem.h"
+#include "lwip/udp.h"
+#include "lwip/tcpip.h"
+#include "lwip/snmp.h"
+
+#include <string.h>
+
+struct ieee_802154_addr {
+  u8_t addr_len;
+  u8_t addr[8];
+};
+
+/** This is a helper struct.
+ */
+struct lowpan6_reass_helper {
+  struct pbuf *pbuf;
+  struct lowpan6_reass_helper *next_packet;
+  u8_t timer;
+  struct ieee_802154_addr sender_addr;
+  u16_t datagram_size;
+  u16_t datagram_tag;
+};
+
+static struct lowpan6_reass_helper * reass_list;
+
+#if LWIP_6LOWPAN_NUM_CONTEXTS > 0
+static ip6_addr_t lowpan6_context[LWIP_6LOWPAN_NUM_CONTEXTS];
+#endif
+
+static u16_t ieee_802154_pan_id;
+
+static const struct ieee_802154_addr ieee_802154_broadcast = {2, {0xff, 0xff}};
+
+#if LWIP_6LOWPAN_INFER_SHORT_ADDRESS
+static struct ieee_802154_addr short_mac_addr = {2, {0,0}};
+#endif /* LWIP_6LOWPAN_INFER_SHORT_ADDRESS */
+
+static err_t dequeue_datagram(struct lowpan6_reass_helper *lrh);
+
+/**
+ * Periodic timer for 6LowPAN functions:
+ *
+ * - Remove incomplete/old packets
+ */
+void
+lowpan6_tmr(void)
+{
+  struct lowpan6_reass_helper *lrh, *lrh_temp;
+
+  lrh = reass_list;
+  while (lrh != NULL) {
+    lrh_temp = lrh->next_packet;
+    if ((--lrh->timer) == 0) {
+      dequeue_datagram(lrh);
+      pbuf_free(lrh->pbuf);
+      mem_free(lrh);
+    }
+    lrh = lrh_temp;
+  }
+}
+
+/**
+ * Removes a datagram from the reassembly queue.
+ **/
+static err_t
+dequeue_datagram(struct lowpan6_reass_helper *lrh)
+{
+  struct lowpan6_reass_helper *lrh_temp;
+
+  if (reass_list == lrh) {
+    reass_list = reass_list->next_packet;
+  } else {
+    lrh_temp = reass_list;
+    while (lrh_temp != NULL) {
+      if (lrh_temp->next_packet == lrh) {
+        lrh_temp->next_packet = lrh->next_packet;
+        break;
+      }
+      lrh_temp = lrh_temp->next_packet;
+    }
+  }
+
+  return ERR_OK;
+}
+
+static s8_t
+lowpan6_context_lookup(const ip6_addr_t *ip6addr)
+{
+  s8_t i;
+
+  for (i = 0; i < LWIP_6LOWPAN_NUM_CONTEXTS; i++) {
+    if (ip6_addr_netcmp(&lowpan6_context[i], ip6addr)) {
+      return i;
+    }
+  }
+
+  return -1;
+}
+
+/* Determine compression mode for unicast address. */
+static s8_t
+lowpan6_get_address_mode(const ip6_addr_t *ip6addr, const struct ieee_802154_addr *mac_addr)
+{
+  if (mac_addr->addr_len == 2) {
+    if ((ip6addr->addr[2] == (u32_t)PP_HTONL(0x000000ff)) &&
+      ((ip6addr->addr[3]  & PP_HTONL(0xffff0000)) == PP_NTOHL(0xfe000000))) {
+      if ((ip6addr->addr[3]  & PP_HTONL(0x0000ffff)) == ntohl((mac_addr->addr[0] << 8) | mac_addr->addr[1])) {
+        return 3;
+      }
+    }
+  } else if (mac_addr->addr_len == 8) {
+    if ((ip6addr->addr[2] == ntohl(((mac_addr->addr[0] ^ 2) << 24) | (mac_addr->addr[1] << 16) | mac_addr->addr[2] << 8 | mac_addr->addr[3])) &&
+      (ip6addr->addr[3] == ntohl((mac_addr->addr[4] << 24) | (mac_addr->addr[5] << 16) | mac_addr->addr[6] << 8 | mac_addr->addr[7]))) {
+      return 3;
+    }
+  }
+
+  if ((ip6addr->addr[2] == PP_HTONL(0x000000ffUL)) &&
+    ((ip6addr->addr[3]  & PP_HTONL(0xffff0000)) == PP_NTOHL(0xfe000000UL))) {
+    return 2;
+  }
+
+  return 1;
+}
+
+/* Determine compression mode for multicast address. */
+static s8_t
+lowpan6_get_address_mode_mc(const ip6_addr_t *ip6addr)
+{
+  if ((ip6addr->addr[0] == PP_HTONL(0xff020000)) &&
+      (ip6addr->addr[1] == 0) &&
+      (ip6addr->addr[2] == 0) &&
+      ((ip6addr->addr[3]  & PP_HTONL(0xffffff00)) == 0)) {
+    return 3;
+  } else if (((ip6addr->addr[0] & PP_HTONL(0xff00ffff)) == PP_HTONL(0xff000000)) &&
+              (ip6addr->addr[1] == 0)) {
+    if ((ip6addr->addr[2] == 0) &&
+        ((ip6addr->addr[3]  & PP_HTONL(0xff000000)) == 0)) {
+      return 2;
+    } else if ((ip6addr->addr[2]  & PP_HTONL(0xffffff00)) == 0) {
+      return 1;
+    }
+  }
+
+  return 0;
+}
+
+/*
+ * Encapsulates data into IEEE 802.15.4 frames.
+ * Fragments an IPv6 datagram into 6LowPAN units, which fit into IEEE 802.15.4 frames.
+ * If configured, will compress IPv6 and or UDP headers.
+ * */
+static err_t
+lowpan6_frag(struct netif *netif, struct pbuf *p, const struct ieee_802154_addr *src, const struct ieee_802154_addr *dst)
+{
+  struct pbuf * p_frag;
+  u16_t frag_len, remaining_len;
+  u8_t * buffer;
+  u8_t ieee_header_len;
+  u8_t lowpan6_header_len;
+  s8_t i;
+  static u8_t frame_seq_num;
+  static u16_t datagram_tag;
+  u16_t datagram_offset;
+  err_t err = ERR_IF;
+
+  /* We'll use a dedicated pbuf for building 6LowPAN fragments. */
+  p_frag = pbuf_alloc(PBUF_RAW, 127, PBUF_RAM);
+  if (p_frag == NULL) {
+    MIB2_STATS_NETIF_INC(netif, ifoutdiscards);
+    return ERR_MEM;
+  }
+
+  /* Write IEEE 802.15.4 header. */
+  buffer  = (u8_t*)p_frag->payload;
+  ieee_header_len = 0;
+  if (dst == &ieee_802154_broadcast) {
+    buffer[ieee_header_len++] = 0x01; /* data packet, no ack required. */
+  } else {
+    buffer[ieee_header_len++] = 0x21; /* data packet, ack required. */
+  }
+  buffer[ieee_header_len] = (0x00 << 4); /* 2003 frame version */
+  buffer[ieee_header_len] |= (dst->addr_len == 2) ? (0x02 << 2) : (0x03 << 2); /* destination addressing mode  */
+  buffer[ieee_header_len] |= (src->addr_len == 2) ? (0x02 << 6) : (0x03 << 6); /* source addressing mode */
+  ieee_header_len++;
+  buffer[ieee_header_len++] = frame_seq_num++;
+
+  buffer[ieee_header_len++] = ieee_802154_pan_id & 0xff; /* pan id */
+  buffer[ieee_header_len++] = (ieee_802154_pan_id >> 8) & 0xff; /* pan id */
+  i = dst->addr_len;
+  while (i-- > 0) {
+    buffer[ieee_header_len++] = dst->addr[i];
+  }
+
+  buffer[ieee_header_len++] = ieee_802154_pan_id & 0xff; /* pan id */
+  buffer[ieee_header_len++] = (ieee_802154_pan_id >> 8) & 0xff; /* pan id */
+  i = src->addr_len;
+  while (i-- > 0) {
+    buffer[ieee_header_len++] = src->addr[i];
+  }
+
+#if LWIP_6LOWPAN_IPHC
+  /* Perform 6LowPAN IPv6 header compression according to RFC 6282 */
+  {
+    struct ip6_hdr *ip6hdr;
+
+    /* Point to ip6 header and align copies of src/dest addresses. */
+    ip6hdr = (struct ip6_hdr *)p->payload;
+    ip_addr_copy_from_ip6(ip_data.current_iphdr_dest, ip6hdr->dest);
+    ip_addr_copy_from_ip6(ip_data.current_iphdr_src, ip6hdr->src);
+
+    /* Basic length of 6LowPAN header, set dispatch and clear fields. */
+    lowpan6_header_len = 2;
+    buffer[ieee_header_len] = 0x60;
+    buffer[ieee_header_len + 1] = 0;
+
+    /* Determine whether there will be a Context Identifier Extension byte or not.
+    * If so, set it already. */
+#if LWIP_6LOWPAN_NUM_CONTEXTS > 0
+    buffer[ieee_header_len + 2] = 0;
+
+    i = lowpan6_context_lookup(ip_2_ip6(&ip_data.current_iphdr_src));
+    if (i >= 0) {
+      /* Stateful source address compression. */
+      buffer[ieee_header_len + 1] |= 0x40;
+      buffer[ieee_header_len + 2] |= (i & 0x0f) << 4;
+    }
+
+    i = lowpan6_context_lookup(ip_2_ip6(&ip_data.current_iphdr_dest));
+    if (i >= 0) {
+      /* Stateful destination address compression. */
+      buffer[ieee_header_len + 1] |= 0x04;
+      buffer[ieee_header_len + 2] |= i & 0x0f;
+    }
+
+    if (buffer[ieee_header_len + 2] != 0x00) {
+      /* Context identifier extension byte is appended. */
+      buffer[ieee_header_len + 1] |= 0x80;
+      lowpan6_header_len++;
+    }
+#endif /* LWIP_6LOWPAN_NUM_CONTEXTS > 0 */
+
+    /* Determine TF field: Traffic Class, Flow Label */
+    if (IP6H_FL(ip6hdr) == 0) {
+      /* Flow label is elided. */
+      buffer[ieee_header_len] |= 0x10;
+      if (IP6H_TC(ip6hdr) == 0) {
+        /* Traffic class (ECN+DSCP) elided too. */
+        buffer[ieee_header_len] |= 0x08;
+      } else {
+        /* Traffic class (ECN+DSCP) appended. */
+        buffer[ieee_header_len + lowpan6_header_len++] = IP6H_TC(ip6hdr);
+      }
+    } else {
+      if (((IP6H_TC(ip6hdr) & 0x3f) == 0)) {
+        /* DSCP portion of Traffic Class is elided, ECN and FL are appended (3 bytes) */
+        buffer[ieee_header_len] |= 0x08;
+
+        buffer[ieee_header_len + lowpan6_header_len] = IP6H_TC(ip6hdr) & 0xc0;
+        buffer[ieee_header_len + lowpan6_header_len++] |= (IP6H_FL(ip6hdr) >> 16) & 0x0f;
+        buffer[ieee_header_len + lowpan6_header_len++] = (IP6H_FL(ip6hdr) >> 8) & 0xff;
+        buffer[ieee_header_len + lowpan6_header_len++] = IP6H_FL(ip6hdr) & 0xff;
+      } else {
+        /* Traffic class and flow label are appended (4 bytes) */
+        buffer[ieee_header_len + lowpan6_header_len++] = IP6H_TC(ip6hdr);
+        buffer[ieee_header_len + lowpan6_header_len++] = (IP6H_FL(ip6hdr) >> 16) & 0x0f;
+        buffer[ieee_header_len + lowpan6_header_len++] = (IP6H_FL(ip6hdr) >> 8) & 0xff;
+        buffer[ieee_header_len + lowpan6_header_len++] = IP6H_FL(ip6hdr) & 0xff;
+      }
+    }
+
+    /* Compress NH?
+    * Only if UDP for now. @todo support other NH compression. */
+    if (IP6H_NEXTH(ip6hdr) == IP6_NEXTH_UDP) {
+      buffer[ieee_header_len] |= 0x04;
+    } else {
+      /* append nexth. */
+      buffer[ieee_header_len + lowpan6_header_len++] = IP6H_NEXTH(ip6hdr);
+    }
+
+    /* Compress hop limit? */
+    if (IP6H_HOPLIM(ip6hdr) == 255) {
+      buffer[ieee_header_len] |= 0x03;
+    } else if (IP6H_HOPLIM(ip6hdr) == 64) {
+      buffer[ieee_header_len] |= 0x02;
+    } else if (IP6H_HOPLIM(ip6hdr) == 1) {
+      buffer[ieee_header_len] |= 0x01;
+    } else {
+      /* append hop limit */
+      buffer[ieee_header_len + lowpan6_header_len++] = IP6H_HOPLIM(ip6hdr);
+    }
+
+    /* Compress source address */
+    if (((buffer[ieee_header_len + 1] & 0x40) != 0) ||
+        (ip6_addr_islinklocal(ip_2_ip6(&ip_data.current_iphdr_src)))) {
+      /* Context-based or link-local source address compression. */
+      i = lowpan6_get_address_mode(ip_2_ip6(&ip_data.current_iphdr_src), src);
+      buffer[ieee_header_len + 1] |= (i & 0x03) << 4;
+      if (i == 1) {
+        MEMCPY(buffer + ieee_header_len + lowpan6_header_len, (u8_t*)p->payload + 16, 8);
+        lowpan6_header_len += 8;
+      } else if (i == 2) {
+        MEMCPY(buffer + ieee_header_len + lowpan6_header_len, (u8_t*)p->payload + 22, 2);
+        lowpan6_header_len += 2;
+      }
+    } else if (ip6_addr_isany(ip_2_ip6(&ip_data.current_iphdr_src))) {
+      /* Special case: mark SAC and leave SAM=0 */
+      buffer[ieee_header_len + 1] |= 0x40;
+    } else {
+      /* Append full address. */
+      MEMCPY(buffer + ieee_header_len + lowpan6_header_len, (u8_t*)p->payload + 8, 16);
+      lowpan6_header_len += 16;
+    }
+
+    /* Compress destination address */
+    if (ip6_addr_ismulticast(ip_2_ip6(&ip_data.current_iphdr_dest))) {
+      /* @todo support stateful multicast address compression */
+
+      buffer[ieee_header_len + 1] |= 0x08;
+
+      i = lowpan6_get_address_mode_mc(ip_2_ip6(&ip_data.current_iphdr_dest));
+      buffer[ieee_header_len + 1] |= i & 0x03;
+      if (i == 0) {
+        MEMCPY(buffer + ieee_header_len + lowpan6_header_len, (u8_t*)p->payload + 24, 16);
+        lowpan6_header_len += 16;
+      } else if (i == 1) {
+        buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[25];
+        MEMCPY(buffer + ieee_header_len + lowpan6_header_len, (u8_t*)p->payload + 35, 5);
+        lowpan6_header_len += 5;
+      } else if (i == 2) {
+        buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[25];
+        MEMCPY(buffer + ieee_header_len + lowpan6_header_len, (u8_t*)p->payload + 37, 3);
+        lowpan6_header_len += 3;
+      } else if (i == 3) {
+        buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[39];
+      }
+    } else if (((buffer[ieee_header_len + 1] & 0x04) != 0) ||
+               (ip6_addr_islinklocal(ip_2_ip6(&ip_data.current_iphdr_dest)))) {
+      /* Context-based or link-local destination address compression. */
+      i = lowpan6_get_address_mode(ip_2_ip6(&ip_data.current_iphdr_dest), dst);
+      buffer[ieee_header_len + 1] |= i & 0x03;
+      if (i == 1) {
+        MEMCPY(buffer + ieee_header_len + lowpan6_header_len, (u8_t*)p->payload + 32, 8);
+        lowpan6_header_len += 8;
+      } else if (i == 2) {
+        MEMCPY(buffer + ieee_header_len + lowpan6_header_len, (u8_t*)p->payload + 38, 2);
+        lowpan6_header_len += 2;
+      }
+    } else {
+      /* Append full address. */
+      MEMCPY(buffer + ieee_header_len + lowpan6_header_len, (u8_t*)p->payload + 24, 16);
+      lowpan6_header_len += 16;
+    }
+
+    /* Move to payload. */
+    pbuf_header(p, -IP6_HLEN);
+
+    /* Compress UDP header? */
+    if (IP6H_NEXTH(ip6hdr) == IP6_NEXTH_UDP) {
+      /* @todo support optional checksum compression */
+
+      buffer[ieee_header_len + lowpan6_header_len] = 0xf0;
+
+      /* determine port compression mode. */
+      if ((((u8_t *)p->payload)[0] == 0xf0) && ((((u8_t *)p->payload)[1] & 0xf0) == 0xb0) &&
+          (((u8_t *)p->payload)[2] == 0xf0) && ((((u8_t *)p->payload)[3] & 0xf0) == 0xb0)) {
+        /* Compress source and dest ports. */
+        buffer[ieee_header_len + lowpan6_header_len++] |= 0x03;
+        buffer[ieee_header_len + lowpan6_header_len++] = ((((u8_t *)p->payload)[1] & 0x0f) << 4) | (((u8_t *)p->payload)[3] & 0x0f);
+      } else if (((u8_t *)p->payload)[0] == 0xf0) {
+        /* Compress source port. */
+        buffer[ieee_header_len + lowpan6_header_len++] |= 0x02;
+        buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[1];
+        buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[2];
+        buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[3];
+      } else if (((u8_t *)p->payload)[2] == 0xf0) {
+        /* Compress dest port. */
+        buffer[ieee_header_len + lowpan6_header_len++] |= 0x01;
+        buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[0];
+        buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[1];
+        buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[3];
+      } else {
+        /* append full ports. */
+        lowpan6_header_len++;
+        buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[0];
+        buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[1];
+        buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[2];
+        buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[3];
+      }
+
+      /* elide length and copy checksum */
+      buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[6];
+      buffer[ieee_header_len + lowpan6_header_len++] = ((u8_t *)p->payload)[7];
+
+      pbuf_header(p, -UDP_HLEN);
+    }
+  }
+
+#else /* LWIP_6LOWPAN_HC */
+  /* Send uncompressed IPv6 header with appropriate dispatch byte. */
+  lowpan6_header_len = 1;
+  buffer[ieee_header_len] = 0x41; /* IPv6 dispatch */
+#endif /* LWIP_6LOWPAN_HC */
+
+  /* Calculate remaining packet length */
+  remaining_len = p->tot_len;
+
+  if (remaining_len > 0x7FF) {
+    MIB2_STATS_NETIF_INC(netif, ifoutdiscards);
+    /* datagram_size must fit into 11 bit */
+    pbuf_free(p_frag);
+    return ERR_VAL;
+  }
+
+  /* Fragment, or 1 packet? */
+  if (remaining_len > (127 - ieee_header_len - lowpan6_header_len - 3)) { /* 127 - header - 1 byte dispatch - 2 bytes CRC */
+    /* We must move the 6LowPAN header to make room for the FRAG header. */
+    i = lowpan6_header_len;
+    while (i-- != 0) {
+      buffer[ieee_header_len + i + 4] = buffer[ieee_header_len + i];
+    }
+
+    /* Now we need to fragment the packet. FRAG1 header first */
+    buffer[ieee_header_len] = 0xc0 | (((p->tot_len + lowpan6_header_len) >> 8) & 0x7);
+    buffer[ieee_header_len + 1] = (p->tot_len + lowpan6_header_len) & 0xff;
+
+    datagram_tag++;
+    buffer[ieee_header_len + 2] = datagram_tag & 0xff;
+    buffer[ieee_header_len + 3] = (datagram_tag >> 8) & 0xff;
+
+    /* Fragment follows. */
+    frag_len = (127 - ieee_header_len - 4 - 2) & 0xf8;
+
+    pbuf_copy_partial(p, buffer + ieee_header_len + lowpan6_header_len + 4, frag_len - lowpan6_header_len, 0);
+    remaining_len -= frag_len - lowpan6_header_len;
+    datagram_offset = frag_len;
+
+    /* 2 bytes CRC */
+#if LWIP_6LOWPAN_HW_CRC
+    /* Leave blank, will be filled by HW. */
+#else /* LWIP_6LOWPAN_HW_CRC */
+    /* @todo calculate CRC */
+#endif /* LWIP_6LOWPAN_HW_CRC */
+
+    /* Calculate frame length */
+    p_frag->len = p_frag->tot_len = ieee_header_len + 4 + frag_len + 2; /* add 2 dummy bytes for crc*/
+
+    /* send the packet */
+    MIB2_STATS_NETIF_ADD(netif, ifoutoctets, p_frag->tot_len);
+    LWIP_DEBUGF(LOWPAN6_DEBUG | LWIP_DBG_TRACE, ("lowpan6_send: sending packet %p\n", (void *)p));
+    err = netif->linkoutput(netif, p_frag);
+
+    while ((remaining_len > 0) && (err == ERR_OK)) {
+      /* new frame, new seq num for ACK */
+      buffer[2] = frame_seq_num++;
+
+      buffer[ieee_header_len] |= 0x20; /* Change FRAG1 to FRAGN */
+
+      buffer[ieee_header_len + 4] = (u8_t)(datagram_offset >> 3); /* datagram offset in FRAGN header (datagram_offset is max. 11 bit) */
+
+      frag_len = (127 - ieee_header_len - 5 - 2) & 0xf8;
+      if (frag_len > remaining_len) {
+        frag_len = remaining_len;
+      }
+
+      pbuf_copy_partial(p, buffer + ieee_header_len + 5, frag_len, p->tot_len - remaining_len);
+      remaining_len -= frag_len;
+      datagram_offset += frag_len;
+
+      /* 2 bytes CRC */
+#if LWIP_6LOWPAN_HW_CRC
+      /* Leave blank, will be filled by HW. */
+#else /* LWIP_6LOWPAN_HW_CRC */
+      /* @todo calculate CRC */
+#endif /* LWIP_6LOWPAN_HW_CRC */
+
+      /* Calculate frame length */
+      p_frag->len = p_frag->tot_len = frag_len + 5 + ieee_header_len + 2;
+
+      /* send the packet */
+      MIB2_STATS_NETIF_ADD(netif, ifoutoctets, p_frag->tot_len);
+      LWIP_DEBUGF(LOWPAN6_DEBUG | LWIP_DBG_TRACE, ("lowpan6_send: sending packet %p\n", (void *)p));
+      err = netif->linkoutput(netif, p_frag);
+    }
+  } else {
+    /* It fits in one frame. */
+    frag_len = remaining_len;
+
+    /* Copy IPv6 packet */
+    pbuf_copy_partial(p, buffer + ieee_header_len + lowpan6_header_len, frag_len, 0);
+    remaining_len = 0;
+
+    /* 2 bytes CRC */
+#if LWIP_6LOWPAN_HW_CRC
+    /* Leave blank, will be filled by HW. */
+#else /* LWIP_6LOWPAN_HW_CRC */
+    /* @todo calculate CRC */
+#endif /* LWIP_6LOWPAN_HW_CRC */
+
+    /* Calculate frame length */
+    p_frag->len = p_frag->tot_len = frag_len + lowpan6_header_len + ieee_header_len + 2;
+
+    /* send the packet */
+    MIB2_STATS_NETIF_ADD(netif, ifoutoctets, p_frag->tot_len);
+    LWIP_DEBUGF(LOWPAN6_DEBUG | LWIP_DBG_TRACE, ("lowpan6_send: sending packet %p\n", (void *)p));
+    err = netif->linkoutput(netif, p_frag);
+  }
+
+  pbuf_free(p_frag);
+
+  return err;
+}
+
+err_t
+lowpan6_set_context(u8_t idx, const ip6_addr_t * context)
+{
+  if (idx >= LWIP_6LOWPAN_NUM_CONTEXTS) {
+    return ERR_ARG;
+  }
+
+  ip6_addr_set(&lowpan6_context[idx], context);
+
+  return ERR_OK;
+}
+
+#if LWIP_6LOWPAN_INFER_SHORT_ADDRESS
+err_t
+lowpan6_set_short_addr(u8_t addr_high, u8_t addr_low)
+{
+  short_mac_addr.addr[0] = addr_high;
+  short_mac_addr.addr[1] = addr_low;
+
+  return ERR_OK;
+}
+#endif /* LWIP_6LOWPAN_INFER_SHORT_ADDRESS */
+
+#if LWIP_IPV4
+err_t
+lowpan4_output(struct netif *netif, struct pbuf *q, const ip4_addr_t *ipaddr)
+{
+  (void)netif;
+  (void)q;
+  (void)ipaddr;
+
+  return ERR_IF;
+}
+#endif /* LWIP_IPV4 */
+
+/**
+ * Resolve and fill-in IEEE 802.15.4 address header for outgoing IPv6 packet.
+ *
+ * Perform Header Compression and fragment if necessary.
+ *
+ * @param netif The lwIP network interface which the IP packet will be sent on.
+ * @param q The pbuf(s) containing the IP packet to be sent.
+ * @param ip6addr The IP address of the packet destination.
+ *
+ * @return
+ */
+err_t
+lowpan6_output(struct netif *netif, struct pbuf *q, const ip6_addr_t *ip6addr)
+{
+  s8_t i;
+  struct ieee_802154_addr src, dest;
+#if LWIP_6LOWPAN_INFER_SHORT_ADDRESS
+  ip6_addr_t ip6_src;
+  struct ip6_hdr * ip6_hdr;
+#endif /* LWIP_6LOWPAN_INFER_SHORT_ADDRESS */
+
+#if LWIP_6LOWPAN_INFER_SHORT_ADDRESS
+  /* Check if we can compress source address (use aligned copy) */
+  ip6_hdr = (struct ip6_hdr *)q->payload;
+  ip6_addr_set(&ip6_src, &ip6_hdr->src);
+  if (lowpan6_get_address_mode(&ip6_src, &short_mac_addr) == 3) {
+    src.addr_len = 2;
+    src.addr[0] = short_mac_addr.addr[0];
+    src.addr[1] = short_mac_addr.addr[1];
+  } else
+#endif /* LWIP_6LOWPAN_INFER_SHORT_ADDRESS */
+  {
+    src.addr_len = netif->hwaddr_len;
+    SMEMCPY(src.addr, netif->hwaddr, netif->hwaddr_len);
+  }
+
+  /* multicast destination IP address? */
+  if (ip6_addr_ismulticast(ip6addr)) {
+    MIB2_STATS_NETIF_INC(netif, ifoutnucastpkts);
+    /* We need to send to the broadcast address.*/
+    return lowpan6_frag(netif, q, &src, &ieee_802154_broadcast);
+  }
+
+  /* We have a unicast destination IP address */
+  /* @todo anycast? */
+
+#if LWIP_6LOWPAN_INFER_SHORT_ADDRESS
+  if (src.addr_len == 2) {
+    /* If source address was compressable to short_mac_addr, and dest has same subnet and
+    * is also compressable to 2-bytes, assume we can infer dest as a short address too. */
+    dest.addr_len = 2;
+    dest.addr[0] = ((u8_t *)q->payload)[38];
+    dest.addr[1] = ((u8_t *)q->payload)[39];
+    if ((src.addr_len == 2) && (ip6_addr_netcmp(&ip6_hdr->src, &ip6_hdr->dest)) &&
+        (lowpan6_get_address_mode(ip6addr, &dest) == 3)) {
+      MIB2_STATS_NETIF_INC(netif, ifoutucastpkts);
+      return lowpan6_frag(netif, q, &src, &dest);
+    }
+  }
+#endif /* LWIP_6LOWPAN_INFER_SHORT_ADDRESS */
+
+
+  /* Get next hop record. */
+  i = nd6_get_next_hop_entry(ip6addr, netif);
+  if (i < 0) {
+    MIB2_STATS_NETIF_INC(netif, ifoutdiscards);
+    /* failed to get a next hop neighbor record. */
+    return ERR_MEM;
+  }
+
+  /* Now that we have a destination record, send or queue the packet. */
+  if (neighbor_cache[i].state == ND6_STALE) {
+    /* Switch to delay state. */
+    neighbor_cache[i].state = ND6_DELAY;
+    neighbor_cache[i].counter.delay_time = LWIP_ND6_DELAY_FIRST_PROBE_TIME;
+  }
+  /* @todo should we send or queue if PROBE? send for now, to let unicast NS pass. */
+  if ((neighbor_cache[i].state == ND6_REACHABLE) ||
+      (neighbor_cache[i].state == ND6_DELAY) ||
+      (neighbor_cache[i].state == ND6_PROBE)) {
+
+    /* Send out. */
+    dest.addr_len = netif->hwaddr_len;
+    SMEMCPY(dest.addr, neighbor_cache[i].lladdr, netif->hwaddr_len);
+    MIB2_STATS_NETIF_INC(netif, ifoutucastpkts);
+    return lowpan6_frag(netif, q, &src, &dest);
+  }
+
+  /* We should queue packet on this interface. */
+  return nd6_queue_packet(i, q);
+}
+
+static struct pbuf *
+lowpan6_decompress(struct pbuf * p, struct ieee_802154_addr * src, struct ieee_802154_addr * dest)
+{
+  struct pbuf * q;
+  u8_t * lowpan6_buffer;
+  s8_t lowpan6_offset;
+  struct ip6_hdr *ip6hdr;
+  s8_t i;
+  s8_t ip6_offset = IP6_HLEN;
+
+
+  q = pbuf_alloc(PBUF_IP, p->len + IP6_HLEN + UDP_HLEN, PBUF_POOL);
+  if (q == NULL) {
+    pbuf_free(p);
+    return NULL;
+  }
+
+  lowpan6_buffer = (u8_t *)p->payload;
+  ip6hdr = (struct ip6_hdr *)q->payload;
+
+  lowpan6_offset = 2;
+  if (lowpan6_buffer[1] & 0x80) {
+    lowpan6_offset++;
+  }
+
+  /* Set IPv6 version, traffic class and flow label. */
+  if ((lowpan6_buffer[0] & 0x18) == 0x00) {
+    IP6H_VTCFL_SET(ip6hdr, 6, lowpan6_buffer[lowpan6_offset], ((lowpan6_buffer[lowpan6_offset+1] & 0x0f) << 16) | (lowpan6_buffer[lowpan6_offset + 2] << 8) | lowpan6_buffer[lowpan6_offset+3]);
+    lowpan6_offset += 4;
+  } else if ((lowpan6_buffer[0] & 0x18) == 0x08) {
+    IP6H_VTCFL_SET(ip6hdr, 6, lowpan6_buffer[lowpan6_offset] & 0xc0, ((lowpan6_buffer[lowpan6_offset] & 0x0f) << 16) | (lowpan6_buffer[lowpan6_offset + 1] << 8) | lowpan6_buffer[lowpan6_offset+2]);
+    lowpan6_offset += 3;
+  } else if ((lowpan6_buffer[0] & 0x18) == 0x10) {
+    IP6H_VTCFL_SET(ip6hdr, 6, lowpan6_buffer[lowpan6_offset],0);
+    lowpan6_offset += 1;
+  } else if ((lowpan6_buffer[0] & 0x18) == 0x18) {
+    IP6H_VTCFL_SET(ip6hdr, 6, 0, 0);
+  }
+
+  /* Set Next Header */
+  if ((lowpan6_buffer[0] & 0x04) == 0x00) {
+    IP6H_NEXTH_SET(ip6hdr, lowpan6_buffer[lowpan6_offset++]);
+  } else {
+    /* We should fill this later with NHC decoding */
+    IP6H_NEXTH_SET(ip6hdr, 0);
+  }
+
+  /* Set Hop Limit */
+  if ((lowpan6_buffer[0] & 0x03) == 0x00) {
+    IP6H_HOPLIM_SET(ip6hdr, lowpan6_buffer[lowpan6_offset++]);
+  } else if ((lowpan6_buffer[0] & 0x03) == 0x01) {
+    IP6H_HOPLIM_SET(ip6hdr, 1);
+  } else if ((lowpan6_buffer[0] & 0x03) == 0x02) {
+    IP6H_HOPLIM_SET(ip6hdr, 64);
+  } else if ((lowpan6_buffer[0] & 0x03) == 0x03) {
+    IP6H_HOPLIM_SET(ip6hdr, 255);
+  }
+
+  /* Source address decoding. */
+  if ((lowpan6_buffer[1] & 0x40) == 0x00) {
+    /* Stateless compression */
+    if ((lowpan6_buffer[1] & 0x30) == 0x00) {
+      /* copy full address */
+      MEMCPY(&ip6hdr->src.addr[0], lowpan6_buffer + lowpan6_offset, 16);
+      lowpan6_offset += 16;
+    } else if ((lowpan6_buffer[1] & 0x30) == 0x10) {
+      ip6hdr->src.addr[0] = PP_HTONL(0xfe800000UL);
+      ip6hdr->src.addr[1] = 0;
+      MEMCPY(&ip6hdr->src.addr[2], lowpan6_buffer + lowpan6_offset, 8);
+      lowpan6_offset += 8;
+    } else if ((lowpan6_buffer[1] & 0x30) == 0x20) {
+      ip6hdr->src.addr[0] = PP_HTONL(0xfe800000UL);
+      ip6hdr->src.addr[1] = 0;
+      ip6hdr->src.addr[2] = PP_HTONL(0x000000ffUL);
+      ip6hdr->src.addr[3] = htonl(0xfe000000UL | (lowpan6_buffer[lowpan6_offset] << 8) |
+                                  lowpan6_buffer[lowpan6_offset+1]);
+      lowpan6_offset += 2;
+    } else if ((lowpan6_buffer[1] & 0x30) == 0x30) {
+      ip6hdr->src.addr[0] = PP_HTONL(0xfe800000UL);
+      ip6hdr->src.addr[1] = 0;
+      if (src->addr_len == 2) {
+        ip6hdr->src.addr[2] = PP_HTONL(0x000000ffUL);
+        ip6hdr->src.addr[3] = htonl(0xfe000000UL | (src->addr[0] << 8) | src->addr[1]);
+      } else {
+        ip6hdr->src.addr[2] = htonl(((src->addr[0] ^ 2) << 24) | (src->addr[1] << 16) |
+                                    (src->addr[2] << 8) | src->addr[3]);
+        ip6hdr->src.addr[3] = htonl((src->addr[4] << 24) | (src->addr[5] << 16) |
+                                    (src->addr[6] << 8) | src->addr[7]);
+      }
+    }
+  } else {
+    /* Stateful compression */
+    if ((lowpan6_buffer[1] & 0x30) == 0x00) {
+      /* ANY address */
+      ip6hdr->src.addr[0] = 0;
+      ip6hdr->src.addr[1] = 0;
+      ip6hdr->src.addr[2] = 0;
+      ip6hdr->src.addr[3] = 0;
+    } else {
+      /* Set prefix from context info */
+      if (lowpan6_buffer[1] & 0x80) {
+        i = (lowpan6_buffer[2] >> 4) & 0x0f;
+      } else {
+        i = 0;
+      }
+      if (i >= LWIP_6LOWPAN_NUM_CONTEXTS) {
+        /* Error */
+        pbuf_free(p);
+        pbuf_free(q);
+        return NULL;
+      }
+
+      ip6hdr->src.addr[0] = lowpan6_context[i].addr[0];
+      ip6hdr->src.addr[1] = lowpan6_context[i].addr[1];
+    }
+
+    if ((lowpan6_buffer[1] & 0x30) == 0x10) {
+      MEMCPY(&ip6hdr->src.addr[2], lowpan6_buffer + lowpan6_offset, 8);
+      lowpan6_offset += 8;
+    } else if ((lowpan6_buffer[1] & 0x30) == 0x20) {
+      ip6hdr->src.addr[2] = PP_HTONL(0x000000ffUL);
+      ip6hdr->src.addr[3] = htonl(0xfe000000UL | (lowpan6_buffer[lowpan6_offset] << 8) | lowpan6_buffer[lowpan6_offset+1]);
+      lowpan6_offset += 2;
+    } else if ((lowpan6_buffer[1] & 0x30) == 0x30) {
+      if (src->addr_len == 2) {
+        ip6hdr->src.addr[2] = PP_HTONL(0x000000ffUL);
+        ip6hdr->src.addr[3] = htonl(0xfe000000UL | (src->addr[0] << 8) | src->addr[1]);
+      } else {
+        ip6hdr->src.addr[2] = htonl(((src->addr[0] ^ 2) << 24) | (src->addr[1] << 16) | (src->addr[2] << 8) | src->addr[3]);
+        ip6hdr->src.addr[3] = htonl((src->addr[4] << 24) | (src->addr[5] << 16) | (src->addr[6] << 8) | src->addr[7]);
+      }
+    }
+  }
+
+  /* Destination address decoding. */
+  if (lowpan6_buffer[1] & 0x08) {
+    /* Multicast destination */
+    if (lowpan6_buffer[1] & 0x04) {
+      /* @todo support stateful multicast addressing */
+      pbuf_free(p);
+      pbuf_free(q);
+      return NULL;
+    }
+
+    if ((lowpan6_buffer[1] & 0x03) == 0x00) {
+      /* copy full address */
+      MEMCPY(&ip6hdr->dest.addr[0], lowpan6_buffer + lowpan6_offset, 16);
+      lowpan6_offset += 16;
+    } else if ((lowpan6_buffer[1] & 0x03) == 0x01) {
+      ip6hdr->dest.addr[0] = htonl(0xff000000UL | (lowpan6_buffer[lowpan6_offset++] << 16));
+      ip6hdr->dest.addr[1] = 0;
+      ip6hdr->dest.addr[2] = htonl(lowpan6_buffer[lowpan6_offset++]);
+      ip6hdr->dest.addr[3] = htonl((lowpan6_buffer[lowpan6_offset] << 24) | (lowpan6_buffer[lowpan6_offset + 1] << 16) | (lowpan6_buffer[lowpan6_offset + 2] << 8) | lowpan6_buffer[lowpan6_offset + 3]);
+      lowpan6_offset += 4;
+    } else if ((lowpan6_buffer[1] & 0x03) == 0x02) {
+      ip6hdr->dest.addr[0] = htonl(0xff000000UL | lowpan6_buffer[lowpan6_offset++]);
+      ip6hdr->dest.addr[1] = 0;
+      ip6hdr->dest.addr[2] = 0;
+      ip6hdr->dest.addr[3] = htonl((lowpan6_buffer[lowpan6_offset] << 16) | (lowpan6_buffer[lowpan6_offset + 1] << 8) | lowpan6_buffer[lowpan6_offset + 2]);
+      lowpan6_offset += 3;
+    } else if ((lowpan6_buffer[1] & 0x03) == 0x03) {
+      ip6hdr->dest.addr[0] = PP_HTONL(0xff020000UL);
+      ip6hdr->dest.addr[1] = 0;
+      ip6hdr->dest.addr[2] = 0;
+      ip6hdr->dest.addr[3] = htonl(lowpan6_buffer[lowpan6_offset++]);
+    }
+
+  } else {
+    if (lowpan6_buffer[1] & 0x04) {
+      /* Stateful destination compression */
+      /* Set prefix from context info */
+      if (lowpan6_buffer[1] & 0x80) {
+        i = lowpan6_buffer[2] & 0x0f;
+      } else {
+        i = 0;
+      }
+      if (i >= LWIP_6LOWPAN_NUM_CONTEXTS) {
+        /* Error */
+        pbuf_free(p);
+        pbuf_free(q);
+        return NULL;
+      }
+
+      ip6hdr->dest.addr[0] = lowpan6_context[i].addr[0];
+      ip6hdr->dest.addr[1] = lowpan6_context[i].addr[1];
+    } else {
+      /* Link local address compression */
+      ip6hdr->dest.addr[0] = PP_HTONL(0xfe800000UL);
+      ip6hdr->dest.addr[1] = 0;
+    }
+
+    if ((lowpan6_buffer[1] & 0x03) == 0x00) {
+      /* copy full address */
+      MEMCPY(&ip6hdr->dest.addr[0], lowpan6_buffer + lowpan6_offset, 16);
+      lowpan6_offset += 16;
+    } else if ((lowpan6_buffer[1] & 0x03) == 0x01) {
+      MEMCPY(&ip6hdr->dest.addr[2], lowpan6_buffer + lowpan6_offset, 8);
+      lowpan6_offset += 8;
+    } else if ((lowpan6_buffer[1] & 0x03) == 0x02) {
+      ip6hdr->dest.addr[2] = PP_HTONL(0x000000ffUL);
+      ip6hdr->dest.addr[3] = htonl(0xfe000000UL | (lowpan6_buffer[lowpan6_offset] << 8) | lowpan6_buffer[lowpan6_offset + 1]);
+      lowpan6_offset += 2;
+    } else if ((lowpan6_buffer[1] & 0x03) == 0x03) {
+      if (dest->addr_len == 2) {
+        ip6hdr->dest.addr[2] = PP_HTONL(0x000000ffUL);
+        ip6hdr->dest.addr[3] = htonl(0xfe000000UL | (dest->addr[0] << 8) | dest->addr[1]);
+      } else {
+        ip6hdr->dest.addr[2] = htonl(((dest->addr[0] ^ 2) << 24) | (dest->addr[1] << 16) | dest->addr[2] << 8 | dest->addr[3]);
+        ip6hdr->dest.addr[3] = htonl((dest->addr[4] << 24) | (dest->addr[5] << 16) | dest->addr[6] << 8 | dest->addr[7]);
+      }
+    }
+  }
+
+
+  /* Next Header Compression (NHC) decoding? */
+  if (lowpan6_buffer[0] & 0x04) {
+    if ((lowpan6_buffer[lowpan6_offset] & 0xf8) == 0xf0) {
+      struct udp_hdr *udphdr;
+
+      /* UDP compression */
+      IP6H_NEXTH_SET(ip6hdr, IP6_NEXTH_UDP);
+      udphdr = (struct udp_hdr *)((u8_t *)q->payload + ip6_offset);
+
+      if (lowpan6_buffer[lowpan6_offset] & 0x04) {
+        /* @todo support checksum decompress */
+        pbuf_free(p);
+        pbuf_free(q);
+        return NULL;
+      }
+
+      /* Decompress ports */
+      i = lowpan6_buffer[lowpan6_offset++] & 0x03;
+      if (i == 0) {
+        udphdr->src = htons(lowpan6_buffer[lowpan6_offset] << 8 | lowpan6_buffer[lowpan6_offset + 1]);
+        udphdr->dest = htons(lowpan6_buffer[lowpan6_offset + 2] << 8 | lowpan6_buffer[lowpan6_offset + 3]);
+        lowpan6_offset += 4;
+      } else if (i == 0x01) {
+        udphdr->src = htons(lowpan6_buffer[lowpan6_offset] << 8 | lowpan6_buffer[lowpan6_offset + 1]);
+        udphdr->dest = htons(0xf000 | lowpan6_buffer[lowpan6_offset + 2]);
+        lowpan6_offset += 3;
+      } else if (i == 0x02) {
+        udphdr->src = htons(0xf000 | lowpan6_buffer[lowpan6_offset]);
+        udphdr->dest = htons(lowpan6_buffer[lowpan6_offset + 1] << 8 | lowpan6_buffer[lowpan6_offset + 2]);
+        lowpan6_offset += 3;
+      } else if (i == 0x03) {
+        udphdr->src = htons(0xf0b0 | ((lowpan6_buffer[lowpan6_offset] >> 4) & 0x0f));
+        udphdr->dest = htons(0xf0b0 | (lowpan6_buffer[lowpan6_offset] & 0x0f));
+        lowpan6_offset += 1;
+      }
+
+      udphdr->chksum = htons(lowpan6_buffer[lowpan6_offset] << 8 | lowpan6_buffer[lowpan6_offset + 1]);
+      lowpan6_offset += 2;
+      udphdr->len = htons(p->tot_len - lowpan6_offset + UDP_HLEN);
+
+      ip6_offset += UDP_HLEN;
+    } else {
+      /* @todo support NHC other than UDP */
+      pbuf_free(p);
+      pbuf_free(q);
+      return NULL;
+    }
+  }
+
+  /* Now we copy leftover contents from p to q, so we have all L2 and L3 headers (and L4?) in a single PBUF.
+  * Replace p with q, and free p */
+  pbuf_header(p, -lowpan6_offset);
+  MEMCPY((u8_t*)q->payload + ip6_offset, p->payload, p->len);
+  q->len = q->tot_len = ip6_offset + p->len;
+  if (p->next != NULL) {
+    pbuf_cat(q, p->next);
+  }
+  p->next = NULL;
+  pbuf_free(p);
+
+  /* Infer IPv6 payload length for header */
+  IP6H_PLEN_SET(ip6hdr, q->tot_len - IP6_HLEN);
+
+  /* all done */
+  return q;
+}
+
+err_t
+lowpan6_input(struct pbuf * p, struct netif *netif)
+{
+  u8_t * puc;
+  s8_t i;
+  struct ieee_802154_addr src, dest;
+  u16_t datagram_size, datagram_offset, datagram_tag;
+  struct lowpan6_reass_helper *lrh, *lrh_temp;
+
+  MIB2_STATS_NETIF_ADD(netif, ifinoctets, p->tot_len);
+
+  /* Analyze header. @todo validate. */
+  puc = (u8_t*)p->payload;
+  datagram_offset = 5;
+  if ((puc[1] & 0x0c) == 0x0c) {
+    dest.addr_len = 8;
+    for (i = 0; i < 8; i++) {
+      dest.addr[i] = puc[datagram_offset + 7 - i];
+    }
+    datagram_offset += 8;
+  } else {
+    dest.addr_len = 2;
+    dest.addr[0] = puc[datagram_offset + 1];
+    dest.addr[1] = puc[datagram_offset];
+    datagram_offset += 2;
+  }
+
+  datagram_offset += 2; /* skip PAN ID. */
+
+  if ((puc[1] & 0xc0) == 0xc0) {
+    src.addr_len = 8;
+    for (i = 0; i < 8; i++) {
+      src.addr[i] = puc[datagram_offset + 7 - i];
+    }
+    datagram_offset += 8;
+  } else {
+    src.addr_len = 2;
+    src.addr[0] = puc[datagram_offset + 1];
+    src.addr[1] = puc[datagram_offset];
+    datagram_offset += 2;
+  }
+
+  pbuf_header(p, -datagram_offset); /* hide IEEE802.15.4 header. */
+
+  /* Check dispatch. */
+  puc = (u8_t*)p->payload;
+
+  if ((*puc & 0xf8) == 0xc0) {
+    /* FRAG1 dispatch. add this packet to reassembly list. */
+    datagram_size = ((u16_t)(puc[0] & 0x07) << 8) | (u16_t)puc[1];
+    datagram_tag = ((u16_t)puc[2] << 8) | (u16_t)puc[3];
+
+    /* check for duplicate */
+    lrh = reass_list;
+    while (lrh != NULL) {
+      if ((lrh->sender_addr.addr_len == src.addr_len) &&
+          (memcmp(lrh->sender_addr.addr, src.addr, src.addr_len) == 0)) {
+        /* address match with packet in reassembly. */
+        if ((datagram_tag == lrh->datagram_tag) && (datagram_size == lrh->datagram_size)) {
+          MIB2_STATS_NETIF_INC(netif, ifindiscards);
+          /* duplicate fragment. */
+          pbuf_free(p);
+          return ERR_OK;
+        } else {
+          /* We are receiving the start of a new datagram. Discard old one (incomplete). */
+          lrh_temp = lrh->next_packet;
+          dequeue_datagram(lrh);
+          pbuf_free(lrh->pbuf);
+          mem_free(lrh);
+
+          /* Check next datagram in queue. */
+          lrh = lrh_temp;
+        }
+      } else {
+        /* Check next datagram in queue. */
+        lrh = lrh->next_packet;
+      }
+    }
+
+    pbuf_header(p, -4); /* hide frag1 dispatch */
+
+    lrh = (struct lowpan6_reass_helper *) mem_malloc(sizeof(struct lowpan6_reass_helper));
+    if (lrh == NULL) {
+      MIB2_STATS_NETIF_INC(netif, ifindiscards);
+      pbuf_free(p);
+      return ERR_MEM;
+    }
+
+    lrh->sender_addr.addr_len = src.addr_len;
+    for (i = 0; i < src.addr_len; i++) {
+      lrh->sender_addr.addr[i] = src.addr[i];
+    }
+    lrh->datagram_size = datagram_size;
+    lrh->datagram_tag = datagram_tag;
+    lrh->pbuf = p;
+    lrh->next_packet = reass_list;
+    lrh->timer = 2;
+    reass_list = lrh;
+
+    return ERR_OK;
+  } else if ((*puc & 0xf8) == 0xe0) {
+    /* FRAGN dispatch, find packet being reassembled. */
+    datagram_size = ((u16_t)(puc[0] & 0x07) << 8) | (u16_t)puc[1];
+    datagram_tag = ((u16_t)puc[2] << 8) | (u16_t)puc[3];
+    datagram_offset = (u16_t)puc[4] << 3;
+    pbuf_header(p, -5); /* hide frag1 dispatch */
+
+    for (lrh = reass_list; lrh != NULL; lrh = lrh->next_packet) {
+      if ((lrh->sender_addr.addr_len == src.addr_len) &&
+          (memcmp(lrh->sender_addr.addr, src.addr, src.addr_len) == 0) &&
+          (datagram_tag == lrh->datagram_tag) &&
+          (datagram_size == lrh->datagram_size)) {
+        break;
+      }
+    }
+    if (lrh == NULL) {
+      /* rogue fragment */
+      MIB2_STATS_NETIF_INC(netif, ifindiscards);
+      pbuf_free(p);
+      return ERR_OK;
+    }
+
+    if (lrh->pbuf->tot_len < datagram_offset) {
+      /* duplicate, ignore. */
+      pbuf_free(p);
+      return ERR_OK;
+    } else if (lrh->pbuf->tot_len > datagram_offset) {
+      MIB2_STATS_NETIF_INC(netif, ifindiscards);
+      /* We have missed a fragment. Delete whole reassembly. */
+      dequeue_datagram(lrh);
+      pbuf_free(lrh->pbuf);
+      mem_free(lrh);
+      pbuf_free(p);
+      return ERR_OK;
+    }
+    pbuf_cat(lrh->pbuf, p);
+    p = NULL;
+
+    /* is packet now complete?*/
+    if (lrh->pbuf->tot_len >= lrh->datagram_size) {
+      /* dequeue from reass list. */
+      dequeue_datagram(lrh);
+
+      /* get pbuf */
+      p = lrh->pbuf;
+
+      /* release helper */
+      mem_free(lrh);
+    } else {
+      return ERR_OK;
+    }
+  }
+
+  if (p == NULL) {
+    return ERR_OK;
+  }
+
+  /* We have a complete packet, check dispatch for headers. */
+  puc = (u8_t*)p->payload;
+
+  if (*puc == 0x41) {
+    /* This is a complete IPv6 packet, just skip dispatch byte. */
+    pbuf_header(p, -1); /* hide dispatch byte. */
+  } else if ((*puc & 0xe0 )== 0x60) {
+    /* IPv6 headers are compressed using IPHC. */
+    p = lowpan6_decompress(p, &src, &dest);
+    if (p == NULL) {
+      MIB2_STATS_NETIF_INC(netif, ifindiscards);
+      return ERR_OK;
+    }
+  } else {
+    MIB2_STATS_NETIF_INC(netif, ifindiscards);
+    pbuf_free(p);
+    return ERR_OK;
+  }
+
+  /* @todo: distinguish unicast/multicast */
+  MIB2_STATS_NETIF_INC(netif, ifinucastpkts);
+
+  return ip6_input(p, netif);
+}
+
+err_t
+lowpan6_if_init(struct netif *netif)
+{
+  netif->name[0] = 'L';
+  netif->name[1] = '6';
+#if LWIP_IPV4
+  netif->output = lowpan4_output;
+#endif /* LWIP_IPV4 */
+  netif->output_ip6 = lowpan6_output;
+
+  MIB2_INIT_NETIF(netif, snmp_ifType_other, 0);
+
+  /* maximum transfer unit */
+  netif->mtu = 1280;
+
+  /* broadcast capability */
+  netif->flags = NETIF_FLAG_BROADCAST /* | NETIF_FLAG_LOWPAN6 */;
+
+  return ERR_OK;
+}
+
+err_t
+lowpan6_set_pan_id(u16_t pan_id)
+{
+  ieee_802154_pan_id = pan_id;
+
+  return ERR_OK;
+}
+
+#if !NO_SYS
+/**
+ * Pass a received packet to tcpip_thread for input processing
+ *
+ * @param p the received packet, p->payload pointing to the
+ *          IEEE 802.15.4 header.
+ * @param inp the network interface on which the packet was received
+ */
+err_t
+tcpip_6lowpan_input(struct pbuf *p, struct netif *inp)
+{
+  return tcpip_inpkt(p, inp, lowpan6_input);
+}
+#endif /* !NO_SYS */
+
+#endif /* LWIP_IPV6 && LWIP_6LOWPAN */

http://git-wip-us.apache.org/repos/asf/incubator-mynewt-core/blob/f5a0f2a0/net/ip/lwip_base/src/netif/ppp/PPPD_FOLLOWUP
----------------------------------------------------------------------
diff --git a/net/ip/lwip_base/src/netif/ppp/PPPD_FOLLOWUP b/net/ip/lwip_base/src/netif/ppp/PPPD_FOLLOWUP
new file mode 100644
index 0000000..c231982
--- /dev/null
+++ b/net/ip/lwip_base/src/netif/ppp/PPPD_FOLLOWUP
@@ -0,0 +1,473 @@
+The lwIP PPP support is based from pppd 2.4.5 (http://ppp.samba.org) with
+huge changes to match code size and memory requirements for embedded devices.
+
+Anyway, pppd has a mature codebase for years and the average commit count
+is getting low on their Git repository, meaning that we can follow what
+is happening on their side and merge what is relevant for lwIP.
+
+So, here is the pppd follow up, so that we don't get away too far from pppd.
+
+
+== Patch fetched from from pppd Debian packages ==
+
+This has nothing to do with pppd, but we merged some good patch from
+Debian and this is a good place to be.
+
+- LCP adaptive echo, so that we don't send LCP echo request if we
+  are receiving data from peer, can be enabled by setting PPP_LCP_ADAPTIVE
+  to true.
+ 
+- IPCP no/replace default route option, were added in the early stage of
+  the ppp port, but it wasn't really helpful and was disabled when adding
+  the new API ppp_set_default() call, which gives the lwIP user control over
+  which one is the default interface, it was actually a requirement if you
+  are doing PPP over PPP (i.e. PPPoL2TP, VPN link, over PPPoE, ADSL link).
+
+- using rp-pppoe pppd exits with EXIT_OK after receiving a timeout waiting
+  for PADO due to no modem attached, bug reported to pppd bug tracker, fixed
+  in Debian but not in the latest (at the time when the port were started)
+  pppd release.
+
+
+== Commits on pppd ==
+
+2010-03-06 - Document +ipv6 and ipv6cp-accept-local
+  e7537958aee79b3f653c601e903cb31d78fb7dcc
+
+Don't care.
+
+
+2010-03-06 - Install pppol2tp plugins with sane permissions
+  406215672cfadc03017341fe03802d1c7294b903
+
+Don't care.
+
+
+2010-03-07 - pppd: Terminate correctly if lcp_lowerup delayed calling
+             fsm_lowerup
+  3eb9e810cfa515543655659b72dde30c54fea0a5
+
+Merged 2012-05-17.
+
+
+2010-03-07 - rp_pppoe: Copy acName and pppd_pppoe_service after option parsing
+  cab58617fd9d328029fffabc788020264b4fa91f
+
+Don't care, is a patch for pppd/plugins/rp-pppoe/plugin.c which is not part
+of the port.
+
+
+2010-08-23 - set and reset options to control environment variables
+             for scripts.
+  2b6310fd24dba8e0fca8999916a162f0a1842a84
+
+We can't fork processes in embedded, therefore all the pppd process run
+feature is disabled in the port, so we don't care about the new
+"environment variables" pppd feature.
+
+
+2010-08-23 - Nit: use _exit when exec fails and restrict values to 0-255
+             per POSIX.
+  2b4ea140432eeba5a007c0d4e6236bd0e0c12ba4
+
+Again, we are not running as a heavy process, so all exit() or _exit() calls
+were removed.
+
+
+2010-08-23 - Fix quote handling in configuration files to be more like shell
+             quoting.
+  3089132cdf5b58dbdfc2daf08ec5c08eb47f8aca
+
+We are not parsing config file, all the filesystem I/O stuff were disabled
+in our port.
+
+
+2010-08-24 - rp-pppoe: allow MTU to be increased up to 1500
+  fd1dcdf758418f040da3ed801ab001b5e46854e7
+
+Only concern changes on RP-PPPoE plugin, which we don't use.
+
+
+2010-09-11 - chat: Allow TIMEOUT value to come from environment variable
+  ae80bf833e48a6202f44a935a68083ae52ad3824
+
+See 2b6310fd24dba8e0fca8999916a162f0a1842a84.
+
+
+2011-03-05 - pppdump: Fix printfs with insufficient arguments
+  7b8db569642c83ba3283745034f2e2c95e459423
+
+pppdump is a ppp tool outside pppd source tree.
+
+
+2012-05-06 - pppd: Don't unconditionally disable VJ compression under Linux
+  d8a66adf98a0e525cf38031b42098d539da6eeb6
+
+Patch for sys-linux.c, which we don't use.
+
+
+2012-05-20 - Remove old version of Linux if_pppol2tp.h
+  c41092dd4c49267f232f6cba3d31c6c68bfdf68d
+
+Not in the port.
+
+
+2012-05-20 - pppd: Make MSCHAP-v2 cope better with packet loss
+  08ef47ca532294eb428238c831616748940e24a2
+
+This is an interesting patch. However it consumes much more memory for
+MSCHAP and I am not sure if the benefit worth it. The PPP client can
+always start the authentication again if it failed for whatever reason.
+
+
+2012-05-20 - scripts: Make poff ignore extra arguments to pppd
+  18f515f32c9f5723a9c2c912601e04335106534b
+
+Again, we are not running scripts.
+
+
+2012-05-20 - rp-pppoe plugin: Print leading zeros in MAC address
+  f5dda0cfc220c4b52e26144096d729e27b30f0f7
+
+Again, we are not using the RP-PPPoE plugin.
+
+
+2012-05-20 - pppd: Notify IPv6 up/down as we do for IPv4
+  845cda8fa18939cf56e60b073f63a7efa65336fc
+
+This is just a patch that adds plugins hooks for IPv6, the plugin interface
+was disabled because we don't have .so plugins in embedded.
+
+
+2012-05-20 - pppd: Enable IPV6 by default and fix some warnings
+  0b6118239615e98959f7e0b4e746bdd197533248
+
+Change on Makefile for IPv6, warnings were already cleared during port.
+
+
+2012-05-20 - contrib: Fix pppgetpass.gtk compilation
+  80a8e2ce257ca12cce723519a0f20ea1d663b14a
+
+Change on Makefile, don't care.
+
+
+2012-05-20 - pppd: Don't crash if crypt() returns NULL
+  04c4348108d847e034dd91066cc6843f60d71731
+
+We are using the PolarSSL DES implementation that does not return NULL.
+
+
+2012-05-20 - pppd: Eliminate some warnings
+  c44ae5e6a7338c96eb463881fe709b2dfaffe568
+
+Again, we are handling compilation warnings on our own.
+
+
+2012-05-20 - rp-pppoe plugin: Import some fixes from rp-pppoe-3.10
+  1817d83e51a411044e730ba89ebdb0480e1c8cd4
+
+Once more, we are not using the RP-PPPoE plugin.
+
+
+2013-01-23 - pppd: Clarify circumstances where DNS1/DNS2 environment variables are set
+  cf2f5c9538b9400ade23446a194729b0a4113b3a
+
+Documentation only.
+
+
+2013-02-03 - ppp: ignore unrecognised radiusclient configuration directives
+  7f736dde0da3c19855997d9e67370e351e15e923
+
+Radius plugin, not in the port.
+
+
+2013-02-03 - pppd: Take out unused %r conversion completely
+  356d8d558d844412119aa18c8e5a113bc6459c7b
+
+Merged 2014-04-15.
+
+
+2013-02-03 - pppd: Arrange to use logwtmp from libutil on Linux
+  9617a7eb137f4fee62799a677a9ecf8d834db3f5
+
+Patch for sys-linux.c, which we don't use.
+
+
+2013-02-03 - pppdump: Eliminate some compiler warnings
+  3e3acf1ba2b3046c072a42c19164788a9e419bd1
+
+pppdump is a ppp tool outside pppd source tree.
+
+
+2013-02-03 - chat: Correct spelling errors in the man page
+  8dea1b969d266ccbf6f3a8c5474eb6dcd8838e3b
+
+Documentation only.
+
+
+2013-02-03 - pppd: Fix spelling errors in man page
+  9e05a25d76b3f83096c661678010320df673df6b
+
+Documentation only.
+
+
+2013-02-03 - plugins/passprompt: Fix potential out-of-bounds array reference
+  8edb889b753056a691a3e4b217a110a35f9fdedb
+
+Plugin patch, we do not have plugins.
+
+
+2013-02-03 - chat: Fix *roff errors in the man page
+  a7c3489eeaf44e83ce592143c7c8a5b5c29f4c48
+
+Documentation only.
+
+
+2013-03-02 - pppd: Fix man page description of case when remote IP address isn't known
+  224841f4799f4f1e2e71bc490c54448d66740f4f
+
+Documentation only.
+
+
+2013-03-02 - pppd: Add master_detach option
+  398ed2585640d198c53e736ee5bbd67f7ce8168e
+
+Option for multilink support, we do not support multilink and this option
+is about detaching from the terminal, which is out of the embedded scope.
+
+
+2013-03-11 - pppd: Default exit status to EXIT_CONNECT_FAILED during connection phase
+  225361d64ae737afdc8cb57579a2f33525461bc9
+
+Commented out in our port, and already fixed by a previously applied Debian patch.
+
+
+2013-03-11 - pppstats: Fix undefined macro in man page
+  d16a3985eade5280b8e171f5dd0670a91cba0d39
+
+Documentation only.
+
+
+2013-05-11 - plugins/radius: Handle bindaddr keyword in radiusclient.conf
+  d883b2dbafeed3ebd9d7a56ab1469373bd001a3b
+
+Radius plugin, not in the port.
+
+
+2013-06-09 - pppoatm: Remove explicit loading of pppoatm kernel module
+  52cd43a84bea524033b918b603698104f221bbb7
+
+PPPoATM plugin, not in the port.
+
+
+2013-06-09 - pppd: Fix segfault in update_db_entry()
+  37476164f15a45015310b9d4b197c2d7db1f7f8f
+
+We do not use the samba db.
+
+
+2013-06-09 - chat: Fix some text that was intended to be literal
+  cd9683676618adcee8add2c3cfa3382341b5a1f6
+
+Documentation only.
+
+
+2013-06-09 - README.pppoe: Minor semantic fix
+  b5b8898af6fd3d44e873cfc66810ace5f1f47e17
+
+Documentation only.
+
+
+2013-06-10 - radius: Handle additional attributes
+  2f581cd986a56f2ec4a95abad4f8297a1b10d7e2
+
+Radius plugin, not in the port.
+
+
+2013-06-10 - chat, pppd: Use \e instead of \\ in man pages
+  8d6942415d22f6ca4377340ca26e345c3f5fa5db
+
+Documentation only.
+
+
+2014-01-02 - pppd: Don't crash if NULL pointer passed to vslprintf for %q or %v
+  906814431bddeb2061825fa1ebad1a967b6d87a9
+
+Merged 2014-04-15.
+
+
+2014-01-02 - pppd: Accept IPCP ConfAck packets containing MS-WINS options
+  a243f217f1c6ac1aa7793806bc88590d077f490a
+
+Merged 2014-04-15.
+
+
+2014-01-02 - config: Update Solaris compiler options and enable CHAPMS and IPV6
+  99c46caaed01b7edba87962aa52b77fad61bfd7b
+
+Solaris port, don't care.
+
+
+2014-01-02 - Update README and patchlevel for 2.4.6 release
+  4043750fca36e7e0eb90d702e048ad1da4929418
+
+Just release stuff.
+
+
+2014-02-18 - pppd: Add option "stop-bits" to set number of serial port stop bits.
+  ad993a20ee485f0d0e2ac4105221641b200da6e2
+
+Low level serial port, not in the port.
+
+
+2014-03-09 - pppd: Separate IPv6 handling for sifup/sifdown
+  b04d2dc6df5c6b5650fea44250d58757ee3dac4a
+
+Reimplemented.
+
+
+2014-03-09 - pppol2tp: Connect up/down events to notifiers and add IPv6 ones
+  fafbe50251efc7d6b4a8be652d085316e112b34f
+
+Not in the port.
+
+
+2014-03-09 - pppd: Add declarations to eliminate compile warnings
+  50967962addebe15c7a7e63116ff46a0441dc464
+
+We are handling compilation warnings on our own
+
+
+2014-03-09 - pppd: Eliminate some unnecessary ifdefs
+  de8da14d845ee6db9236ccfddabf1d8ebf045ddb
+
+We mostly did that previously. Anyway, merged 2014-12-24.
+
+
+2014-08-01 - radius: Fix realms-config-file option
+  880a81be7c8e0fe8567227bc17a1bff3ea035943
+
+Radius plugin, not in the port.
+
+
+2014-08-01 - pppd: Eliminate potential integer overflow in option parsing
+  7658e8257183f062dc01f87969c140707c7e52cb
+
+pppd config file parser, not in the port.
+
+
+2014-08-01 - pppd: Eliminate memory leak with multiple instances of a string option
+  b94b7fbbaa0589aa6ec5fdc733aeb9ff294d2656
+
+pppd config file parser, not in the port.
+
+
+2014-08-01 - pppd: Fix a stack variable overflow in MSCHAP-v2
+  36733a891fb56594fcee580f667b33a64b990981
+
+This fixes a bug introduced in 08ef47ca ("pppd: Make MSCHAP-v2 cope better with packet loss").
+
+We didn't merge 08ef47ca ;-)
+
+
+2014-08-01 - winbind plugin: Add -DMPPE=1 to eliminate compiler warnings
+  2b05e22c62095e97dd0a97e4b5588402c2185071
+
+Linux plugin, not in the port.
+
+
+2014-08-09 - Update README and patchlevel for 2.4.7 release
+  6e8eaa7a78b31cdab2edf140a9c8afdb02ffaca5
+
+Just release stuff.
+
+
+2014-08-10 - abort on errors in subdir builds
+  5e90783d11a59268e05f4cfb29ce2343b13e8ab2
+
+Linux Makefile, not in the port.
+
+
+2014-06-03 - pppd: add support for defaultroute-metric option
+  35e5a569c988b1ff865b02a24d9a727a00db4da9
+
+Only necessary for Linux, lwIP does not support route metrics.
+
+
+2014-12-13 - scripts: Avoid killing wrong pppd
+  67811a647d399db5d188a242827760615a0f86b5
+
+pppd helper script, not in the port.
+
+
+2014-12-20 - pppd: Fix sign-extension when displaying bytes in octal
+  5e8c3cb256a7e86e3572a82a75d51c6850efdbdc
+
+Merged 2016-07-02.
+
+
+2015-03-01 - Suppress false error message on PPPoE disconnect
+  219aac3b53d0827549377f1bfe22853ee52d4405
+
+PPPoE plugin, not in the port.
+
+
+2015-03-01 - Send PADT on PPPoE disconnect
+  cd2c14f998c57bbe6a01dc5854f2763c0d7f31fb
+
+PPPoE plugin, not in the port. And our PPPoE implementation already does
+that: pppoe_disconnect() calls pppoe_send_padt().
+
+
+2015-08-14 - pppd: ipxcp: Prevent buffer overrun on remote router name
+  fe149de624f96629a7f46732055d8f718c74b856
+
+We never ported IPX support. lwIP does not support IPX.
+
+
+2015-03-25 - pppd: Fix ccp_options.mppe type
+  234edab99a6bb250cc9ecd384cca27b0c8b475ce
+
+We found that while working on MPPE support in lwIP, that's our patch ;-)
+
+
+2015-03-24 - pppd: Fix ccp_cilen calculated size if both deflate_correct and deflate_draft are enabled
+  094cb8ae4c61db225e67fedadb4964f846dd0c27
+
+We found that while working on MPPE support in lwIP, that's our patch ;-)
+
+
+2015-08-14 - Merge branch 'master' of https://github.com/ncopa/ppp
+  3a5c9a8fbc8970375cd881151d44e4b6fe249c6a
+
+Merge commit, we don't care.
+
+
+2015-08-14 - Merge branch 'master' of git://github.com/vapier/ppp
+  912e4fc6665aca188dced7ea7fdc663ce5a2dd24
+
+Merge commit, we don't care.
+
+
+2015-08-14 - Merge branch 'bug_fix' of git://github.com/radaiming/ppp
+  dfd33d7f526ecd7b39dd1bba8101260d02af5ebb
+
+Merge commit, we don't care.
+
+
+2015-08-14 - Merge branch 'master' of git://github.com/pprindeville/ppp
+  aa4a985f6114d08cf4e47634fb6325da71016473
+
+Merge commit, we don't care.
+
+
+2015-08-14 - Merge branch 'no-error-on-already-closed' of git://github.com/farnz/ppp
+  6edf252483b30dbcdcc5059f01831455365d5b6e
+
+Merge commit, we don't care.
+
+
+2015-08-14 - Merge branch 'send-padt-on-disconnect' of git://github.com/farnz/ppp
+  84684243d651f55f6df69d2a6707b52fbbe62bb9
+
+Merge commit, we don't care.