/* * Copyright (c) 2008, Swedish Institute of Computer Science. * 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. Neither the name of the Institute nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``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 INSTITUTE OR CONTRIBUTORS 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 Contiki operating system. * */ /** * \file * 6lowpan implementation (RFC4944 and draft-ietf-6lowpan-hc-06) * * \author Adam Dunkels * \author Nicolas Tsiftes * \author Niclas Finne * \author Mathilde Durvy * \author Julien Abeille * \author Joakim Eriksson * \author Joel Hoglund */ /** * \addtogroup sicslowpan * \ingroup uip * @{ */ /** * FOR HC-06 COMPLIANCE TODO: * -Add compression options to UDP, currently only supports * both ports compressed or both ports elided * * -Verify TC/FL compression works * * -Add stateless multicast option */ #include #include "contiki.h" #include "dev/watchdog.h" #include "net/link-stats.h" #include "net/ipv6/tcpip.h" #include "net/ipv6/uip.h" #include "net/ipv6/uip-ds6.h" #include "net/ipv6/sicslowpan.h" #include "net/netstack.h" #include "net/packetbuf.h" #include "net/queuebuf.h" #if UIP_CONF_IPV6_RPL_LITE == 1 #include "net/rpl-lite/rpl.h" #else /* UIP_CONF_IPV6_RPL_LITE == 1 */ #include "net/rpl-classic/rpl.h" #include "net/rpl-classic/rpl-private.h" #endif /* UIP_CONF_IPV6_RPL_LITE == 1 */ /* Log configuration */ #include "sys/log.h" #define LOG_MODULE "6LoWPAN" #define LOG_LEVEL LOG_LEVEL_6LOWPAN #ifdef SICSLOWPAN_CONF_COMPRESSION #define SICSLOWPAN_COMPRESSION SICSLOWPAN_CONF_COMPRESSION #else /* SICSLOWPAN_CONF_COMPRESSION */ #define SICSLOWPAN_COMPRESSION SICSLOWPAN_COMPRESSION_IPHC #endif /* SICSLOWPAN_CONF_COMPRESSION */ #define GET16(ptr,index) (((uint16_t)((ptr)[index] << 8)) | ((ptr)[(index) + 1])) #define SET16(ptr,index,value) do { \ (ptr)[index] = ((value) >> 8) & 0xff; \ (ptr)[index + 1] = (value) & 0xff; \ } while(0) /** \name Pointers in the packetbuf buffer * @{ */ #define PACKETBUF_FRAG_PTR (packetbuf_ptr) #define PACKETBUF_FRAG_DISPATCH_SIZE 0 /* 16 bit */ #define PACKETBUF_FRAG_TAG 2 /* 16 bit */ #define PACKETBUF_FRAG_OFFSET 4 /* 8 bit */ /* define the buffer as a byte array */ #define PACKETBUF_IPHC_BUF ((uint8_t *)(packetbuf_ptr + packetbuf_hdr_len)) #define PACKETBUF_6LO_PTR (packetbuf_ptr + packetbuf_hdr_len) #define PACKETBUF_6LO_DISPATCH 0 /* 8 bit */ #define PACKETBUF_6LO_ENCODING 1 /* 8 bit */ #define PACKETBUF_6LO_TTL 2 /* 8 bit */ #define PACKETBUF_6LO_HC_UDP_PTR (packetbuf_ptr + packetbuf_hdr_len) #define PACKETBUF_6LO_HC_UDP_DISPATCH 0 /* 8 bit */ #define PACKETBUF_6LO_HC_UDP_HC1_ENCODING 1 /* 8 bit */ #define PACKETBUF_6LO_HC_UDP_UDP_ENCODING 2 /* 8 bit */ #define PACKETBUF_6LO_HC_UDP_TTL 3 /* 8 bit */ #define PACKETBUF_6LO_HC_UDP_PORTS 4 /* 8 bit */ #define PACKETBUF_6LO_HC_UDP_CHKSUM 5 /* 16 bit */ /** \name Pointers in the sicslowpan and uip buffer * @{ */ /* NOTE: In the multiple-reassembly context there is only room for the header / first fragment */ #define SICSLOWPAN_IP_BUF(buf) ((struct uip_ip_hdr *)buf) #define SICSLOWPAN_UDP_BUF(buf) ((struct uip_udp_hdr *)&buf[UIP_IPH_LEN]) #define SICSLOWPAN_IPPAYLOAD_BUF(buf) (&buf[UIP_LLIPH_LEN]) #define UIP_IP_BUF ((struct uip_ip_hdr *)&uip_buf[UIP_LLH_LEN]) #define UIP_UDP_BUF(p) ((struct uip_udp_hdr *)&uip_buf[UIP_LLIPH_LEN + p]) #define UIP_TCP_BUF ((struct uip_tcp_hdr *)&uip_buf[UIP_LLIPH_LEN]) #define UIP_ICMP_BUF ((struct uip_icmp_hdr *)&uip_buf[UIP_LLIPH_LEN]) #define UIP_IPPAYLOAD_BUF(pos) (&uip_buf[UIP_LLIPH_LEN + pos]) /** @} */ /** \brief Maximum available size for frame headers, link layer security-related overhead, as well as 6LoWPAN payload. */ #ifdef SICSLOWPAN_CONF_MAC_MAX_PAYLOAD #define MAC_MAX_PAYLOAD SICSLOWPAN_CONF_MAC_MAX_PAYLOAD #else /* SICSLOWPAN_CONF_MAC_MAX_PAYLOAD */ #define MAC_MAX_PAYLOAD (127 - 2) #endif /* SICSLOWPAN_CONF_MAC_MAX_PAYLOAD */ /** \brief Fixed size of a frame header. This value is * used in case framer returns an error or if SICSLOWPAN_USE_FIXED_HDRLEN * is defined. */ #ifndef SICSLOWPAN_FIXED_HDRLEN #define SICSLOWPAN_FIXED_HDRLEN 21 #endif /* set this to zero if not compressing EXT_HDR - for backwards compatibility */ #ifdef SICSLOWPAN_CONF_COMPRESS_EXT_HDR #define COMPRESS_EXT_HDR SICSLOWPAN_CONF_COMPRESS_EXT_HDR #else /* Compressing on by default - turn off to be compatible with older versions */ #define COMPRESS_EXT_HDR 1 #endif #if COMPRESS_EXT_HDR #define IS_COMPRESSABLE_PROTO(x) (x == UIP_PROTO_UDP \ || x == UIP_PROTO_HBHO \ || x == UIP_PROTO_DESTO \ || x == UIP_PROTO_ROUTING \ || x == UIP_PROTO_FRAG) #else #define IS_COMPRESSABLE_PROTO(x) (x == UIP_PROTO_UDP) #endif /* COMPRESS_EXT_HDR */ /** \name General variables * @{ */ /** * A pointer to the packetbuf buffer. * We initialize it to the beginning of the packetbuf buffer, then * access different fields by updating the offset packetbuf_hdr_len. */ static uint8_t *packetbuf_ptr; /** * packetbuf_hdr_len is the total length of (the processed) 6lowpan headers * (fragment headers, IPV6 or HC1, HC2, and HC1 and HC2 non compressed * fields). */ static uint8_t packetbuf_hdr_len; /** * The length of the payload in the Packetbuf buffer. * The payload is what comes after the compressed or uncompressed * headers (can be the IP payload if the IP header only is compressed * or the UDP payload if the UDP header is also compressed) */ static int packetbuf_payload_len; /** * uncomp_hdr_len is the length of the headers before compression (if HC2 * is used this includes the UDP header in addition to the IP header). */ static uint8_t uncomp_hdr_len; /** * The current page (RFC 4944) */ static uint8_t curr_page; /** * the result of the last transmitted fragment */ static int last_tx_status; /** @} */ static int last_rssi; /* ----------------------------------------------------------------- */ /* Support for reassembling multiple packets */ /* ----------------------------------------------------------------- */ #if SICSLOWPAN_CONF_FRAG static uint16_t my_tag; /** The total length of the IPv6 packet in the sicslowpan_buf. */ /* This needs to be defined in NBR / Nodes depending on available RAM */ /* and expected reassembly requirements */ #ifdef SICSLOWPAN_CONF_FRAGMENT_BUFFERS #define SICSLOWPAN_FRAGMENT_BUFFERS SICSLOWPAN_CONF_FRAGMENT_BUFFERS #else #define SICSLOWPAN_FRAGMENT_BUFFERS 12 #endif /* REASS_CONTEXTS corresponds to the number of simultaneous * reassemblies that can be made. NOTE: the first buffer for each * reassembly is stored in the context since it can be larger than the * rest of the fragments due to header compression. **/ #ifdef SICSLOWPAN_CONF_REASS_CONTEXTS #define SICSLOWPAN_REASS_CONTEXTS SICSLOWPAN_CONF_REASS_CONTEXTS #else #define SICSLOWPAN_REASS_CONTEXTS 2 #endif /* The size of each fragment (IP payload) for the 6lowpan fragmentation */ #ifdef SICSLOWPAN_CONF_FRAGMENT_SIZE #define SICSLOWPAN_FRAGMENT_SIZE SICSLOWPAN_CONF_FRAGMENT_SIZE #else /* The default fragment size (110 bytes for 127-2 bytes frames) */ #define SICSLOWPAN_FRAGMENT_SIZE (MAC_MAX_PAYLOAD - 15) #endif /* Assuming that the worst growth for uncompression is 38 bytes */ #define SICSLOWPAN_FIRST_FRAGMENT_SIZE (SICSLOWPAN_FRAGMENT_SIZE + 38) /* all information needed for reassembly */ struct sicslowpan_frag_info { /** When reassembling, the source address of the fragments being merged */ linkaddr_t sender; /** The destination address of the fragments being merged */ linkaddr_t receiver; /** When reassembling, the tag in the fragments being merged. */ uint16_t tag; /** Total length of the fragmented packet */ uint16_t len; /** Current length of reassembled fragments */ uint16_t reassembled_len; /** Reassembly %process %timer. */ struct timer reass_timer; /** Fragment size of first fragment */ uint16_t first_frag_len; /** First fragment - needs a larger buffer since the size is uncompressed size and we need to know total size to know when we have received last fragment. */ uint8_t first_frag[SICSLOWPAN_FIRST_FRAGMENT_SIZE]; }; static struct sicslowpan_frag_info frag_info[SICSLOWPAN_REASS_CONTEXTS]; struct sicslowpan_frag_buf { /* the index of the frag_info */ uint8_t index; /* Fragment offset */ uint8_t offset; /* Length of this fragment (if zero this buffer is not allocated) */ uint8_t len; uint8_t data[SICSLOWPAN_FRAGMENT_SIZE]; }; static struct sicslowpan_frag_buf frag_buf[SICSLOWPAN_FRAGMENT_BUFFERS]; /*---------------------------------------------------------------------------*/ static int clear_fragments(uint8_t frag_info_index) { int i, clear_count; clear_count = 0; frag_info[frag_info_index].len = 0; for(i = 0; i < SICSLOWPAN_FRAGMENT_BUFFERS; i++) { if(frag_buf[i].len > 0 && frag_buf[i].index == frag_info_index) { /* deallocate the buffer */ frag_buf[i].len = 0; clear_count++; } } return clear_count; } /*---------------------------------------------------------------------------*/ static int timeout_fragments(int not_context) { int i; int count = 0; for(i = 0; i < SICSLOWPAN_REASS_CONTEXTS; i++) { if(frag_info[i].len > 0 && i != not_context && timer_expired(&frag_info[i].reass_timer)) { /* This context can be freed */ count += clear_fragments(i); } } return count; } /*---------------------------------------------------------------------------*/ static int store_fragment(uint8_t index, uint8_t offset) { int i; for(i = 0; i < SICSLOWPAN_FRAGMENT_BUFFERS; i++) { if(frag_buf[i].len == 0) { /* copy over the data from packetbuf into the fragment buffer and store offset and len */ frag_buf[i].offset = offset; /* frag offset */ frag_buf[i].len = packetbuf_datalen() - packetbuf_hdr_len; frag_buf[i].index = index; memcpy(frag_buf[i].data, packetbuf_ptr + packetbuf_hdr_len, packetbuf_datalen() - packetbuf_hdr_len); LOG_INFO("Fragsize: %d\n", frag_buf[i].len); /* return the length of the stored fragment */ return frag_buf[i].len; } } /* failed */ return -1; } /*---------------------------------------------------------------------------*/ /* add a new fragment to the buffer */ static int8_t add_fragment(uint16_t tag, uint16_t frag_size, uint8_t offset) { int i; int len; int8_t found = -1; if(offset == 0) { /* This is a first fragment - check if we can add this */ for(i = 0; i < SICSLOWPAN_REASS_CONTEXTS; i++) { /* clear all fragment info with expired timer to free all fragment buffers */ if(frag_info[i].len > 0 && timer_expired(&frag_info[i].reass_timer)) { clear_fragments(i); } /* We use len as indication on used or not used */ if(found < 0 && frag_info[i].len == 0) { /* We remember the first free fragment info but must continue the loop to free any other expired fragment buffers. */ found = i; } } if(found < 0) { LOG_WARN("*** Failed to store new fragment session - tag: %d\n", tag); return -1; } /* Found a free fragment info to store data in */ frag_info[found].len = frag_size; frag_info[found].tag = tag; linkaddr_copy(&frag_info[found].sender, packetbuf_addr(PACKETBUF_ADDR_SENDER)); timer_set(&frag_info[found].reass_timer, SICSLOWPAN_REASS_MAXAGE * CLOCK_SECOND / 16); /* first fragment can not be stored immediately but is moved into the buffer while uncompressing */ return found; } /* This is a N-fragment - should find the info */ for(i = 0; i < SICSLOWPAN_REASS_CONTEXTS; i++) { if(frag_info[i].tag == tag && frag_info[i].len > 0 && linkaddr_cmp(&frag_info[i].sender, packetbuf_addr(PACKETBUF_ADDR_SENDER))) { /* Tag and Sender match - this must be the correct info to store in */ found = i; break; } } if(found < 0) { /* no entry found for storing the new fragment */ LOG_WARN("*** Failed to store N-fragment - could not find session - tag: %d offset: %d\n", tag, offset); return -1; } /* i is the index of the reassembly context */ len = store_fragment(i, offset); if(len < 0 && timeout_fragments(i) > 0) { len = store_fragment(i, offset); } if(len > 0) { frag_info[i].reassembled_len += len; return i; } else { /* should we also clear all fragments since we failed to store this fragment? */ LOG_WARN("*** Failed to store fragment - packet reassembly will fail tag:%d l\n", frag_info[i].tag); return -1; } } /*---------------------------------------------------------------------------*/ /* Copy all the fragments that are associated with a specific context into uip */ static void copy_frags2uip(int context) { int i; /* Copy from the fragment context info buffer first */ memcpy((uint8_t *)UIP_IP_BUF, (uint8_t *)frag_info[context].first_frag, frag_info[context].first_frag_len); for(i = 0; i < SICSLOWPAN_FRAGMENT_BUFFERS; i++) { /* And also copy all matching fragments */ if(frag_buf[i].len > 0 && frag_buf[i].index == context) { memcpy((uint8_t *)UIP_IP_BUF + (uint16_t)(frag_buf[i].offset << 3), (uint8_t *)frag_buf[i].data, frag_buf[i].len); } } /* deallocate all the fragments for this context */ clear_fragments(context); } #endif /* SICSLOWPAN_CONF_FRAG */ /* -------------------------------------------------------------------------- */ /*-------------------------------------------------------------------------*/ /* Basic netstack sniffer */ /*-------------------------------------------------------------------------*/ static struct netstack_sniffer *callback = NULL; void netstack_sniffer_add(struct netstack_sniffer *s) { callback = s; } void netstack_sniffer_remove(struct netstack_sniffer *s) { callback = NULL; } static void set_packet_attrs(void) { int c = 0; /* set protocol in NETWORK_ID */ packetbuf_set_attr(PACKETBUF_ATTR_NETWORK_ID, UIP_IP_BUF->proto); /* assign values to the channel attribute (port or type + code) */ if(UIP_IP_BUF->proto == UIP_PROTO_UDP) { c = UIP_UDP_BUF(0)->srcport; if(UIP_UDP_BUF(0)->destport < c) { c = UIP_UDP_BUF(0)->destport; } } else if(UIP_IP_BUF->proto == UIP_PROTO_TCP) { c = UIP_TCP_BUF->srcport; if(UIP_TCP_BUF->destport < c) { c = UIP_TCP_BUF->destport; } } else if(UIP_IP_BUF->proto == UIP_PROTO_ICMP6) { c = UIP_ICMP_BUF->type << 8 | UIP_ICMP_BUF->icode; } packetbuf_set_attr(PACKETBUF_ATTR_CHANNEL, c); /* if(uip_ds6_is_my_addr(&UIP_IP_BUF->srcipaddr)) { */ /* own = 1; */ /* } */ } #if SICSLOWPAN_COMPRESSION >= SICSLOWPAN_COMPRESSION_IPHC /** \name variables specific to HC06 and more recent versions * @{ */ /** Addresses contexts for IPHC. */ #if SICSLOWPAN_CONF_MAX_ADDR_CONTEXTS > 0 static struct sicslowpan_addr_context addr_contexts[SICSLOWPAN_CONF_MAX_ADDR_CONTEXTS]; #endif /** pointer to an address context. */ static struct sicslowpan_addr_context *context; /** pointer to the byte where to write next inline field. */ static uint8_t *hc06_ptr; /* Uncompression of linklocal */ /* 0 -> 16 bytes from packet */ /* 1 -> 2 bytes from prefix - bunch of zeroes and 8 from packet */ /* 2 -> 2 bytes from prefix - 0000::00ff:fe00:XXXX from packet */ /* 3 -> 2 bytes from prefix - infer 8 bytes from lladdr */ /* NOTE: => the uncompress function does change 0xf to 0x10 */ /* NOTE: 0x00 => no-autoconfig => unspecified */ const uint8_t unc_llconf[] = {0x0f,0x28,0x22,0x20}; /* Uncompression of ctx-based */ /* 0 -> 0 bits from packet [unspecified / reserved] */ /* 1 -> 8 bytes from prefix - bunch of zeroes and 8 from packet */ /* 2 -> 8 bytes from prefix - 0000::00ff:fe00:XXXX + 2 from packet */ /* 3 -> 8 bytes from prefix - infer 8 bytes from lladdr */ const uint8_t unc_ctxconf[] = {0x00,0x88,0x82,0x80}; /* Uncompression of ctx-based */ /* 0 -> 0 bits from packet */ /* 1 -> 2 bytes from prefix - bunch of zeroes 5 from packet */ /* 2 -> 2 bytes from prefix - zeroes + 3 from packet */ /* 3 -> 2 bytes from prefix - infer 1 bytes from lladdr */ const uint8_t unc_mxconf[] = {0x0f, 0x25, 0x23, 0x21}; /* Link local prefix */ const uint8_t llprefix[] = {0xfe, 0x80}; /* TTL uncompression values */ static const uint8_t ttl_values[] = {0, 1, 64, 255}; /*--------------------------------------------------------------------*/ /** \name IPHC related functions * @{ */ /*--------------------------------------------------------------------*/ /** \brief find the context corresponding to prefix ipaddr */ static struct sicslowpan_addr_context* addr_context_lookup_by_prefix(uip_ipaddr_t *ipaddr) { /* Remove code to avoid warnings and save flash if no context is used */ #if SICSLOWPAN_CONF_MAX_ADDR_CONTEXTS > 0 int i; for(i = 0; i < SICSLOWPAN_CONF_MAX_ADDR_CONTEXTS; i++) { if((addr_contexts[i].used == 1) && uip_ipaddr_prefixcmp(&addr_contexts[i].prefix, ipaddr, 64)) { return &addr_contexts[i]; } } #endif /* SICSLOWPAN_CONF_MAX_ADDR_CONTEXTS > 0 */ return NULL; } /*--------------------------------------------------------------------*/ /** \brief find the context with the given number */ static struct sicslowpan_addr_context* addr_context_lookup_by_number(uint8_t number) { /* Remove code to avoid warnings and save flash if no context is used */ #if SICSLOWPAN_CONF_MAX_ADDR_CONTEXTS > 0 int i; for(i = 0; i < SICSLOWPAN_CONF_MAX_ADDR_CONTEXTS; i++) { if((addr_contexts[i].used == 1) && addr_contexts[i].number == number) { return &addr_contexts[i]; } } #endif /* SICSLOWPAN_CONF_MAX_ADDR_CONTEXTS > 0 */ return NULL; } /*--------------------------------------------------------------------*/ static uint8_t compress_addr_64(uint8_t bitpos, uip_ipaddr_t *ipaddr, uip_lladdr_t *lladdr) { if(uip_is_addr_mac_addr_based(ipaddr, lladdr)) { return 3 << bitpos; /* 0-bits */ } else if(sicslowpan_is_iid_16_bit_compressable(ipaddr)) { /* compress IID to 16 bits xxxx::0000:00ff:fe00:XXXX */ memcpy(hc06_ptr, &ipaddr->u16[7], 2); hc06_ptr += 2; return 2 << bitpos; /* 16-bits */ } else { /* do not compress IID => xxxx::IID */ memcpy(hc06_ptr, &ipaddr->u16[4], 8); hc06_ptr += 8; return 1 << bitpos; /* 64-bits */ } } /*-------------------------------------------------------------------- */ /* Uncompress addresses based on a prefix and a postfix with zeroes in * between. If the postfix is zero in length it will use the link address * to configure the IP address (autoconf style). * pref_post_count takes a byte where the first nibble specify prefix count * and the second postfix count (NOTE: 15/0xf => 16 bytes copy). */ static void uncompress_addr(uip_ipaddr_t *ipaddr, uint8_t const prefix[], uint8_t pref_post_count, uip_lladdr_t *lladdr) { uint8_t prefcount = pref_post_count >> 4; uint8_t postcount = pref_post_count & 0x0f; /* full nibble 15 => 16 */ prefcount = prefcount == 15 ? 16 : prefcount; postcount = postcount == 15 ? 16 : postcount; LOG_INFO("Uncompressing %d + %d => ", prefcount, postcount); if(prefcount > 0) { memcpy(ipaddr, prefix, prefcount); } if(prefcount + postcount < 16) { memset(&ipaddr->u8[prefcount], 0, 16 - (prefcount + postcount)); } if(postcount > 0) { memcpy(&ipaddr->u8[16 - postcount], hc06_ptr, postcount); if(postcount == 2 && prefcount < 11) { /* 16 bits uncompression => 0000:00ff:fe00:XXXX */ ipaddr->u8[11] = 0xff; ipaddr->u8[12] = 0xfe; } hc06_ptr += postcount; } else if (prefcount > 0) { /* no IID based configuration if no prefix and no data => unspec */ uip_ds6_set_addr_iid(ipaddr, lladdr); } LOG_INFO_6ADDR(ipaddr); LOG_INFO_("\n"); } /*--------------------------------------------------------------------*/ /** * \brief Compress IP/UDP header * * This function is called by the 6lowpan code to create a compressed * 6lowpan packet in the packetbuf buffer from a full IPv6 packet in the * uip_buf buffer. * * * IPHC (RFC 6282)\n * http://tools.ietf.org/html/ * * \note We do not support ISA100_UDP header compression * * For LOWPAN_UDP compression, we either compress both ports or none. * General format with LOWPAN_UDP compression is * \verbatim * 1 2 3 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * |0|1|1|TF |N|HLI|C|S|SAM|M|D|DAM| SCI | DCI | comp. IPv6 hdr| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | compressed IPv6 fields ..... | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | LOWPAN_UDP | non compressed UDP fields ... | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | L4 data ... | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * \endverbatim * \note The context number 00 is reserved for the link local prefix. * For unicast addresses, if we cannot compress the prefix, we neither * compress the IID. * \param link_destaddr L2 destination address, needed to compress IP * dest */ static void compress_hdr_iphc(linkaddr_t *link_destaddr) { uint8_t tmp, iphc0, iphc1, *next_hdr, *next_nhc; int ext_hdr_len; struct uip_udp_hdr *udp_buf; #if LOG_DBG_ENABLED { uint16_t ndx; LOG_DBG("before compression (%d): ", UIP_IP_BUF->len[1]); for(ndx = 0; ndx < UIP_IP_BUF->len[1] + 40; ndx++) { uint8_t data = ((uint8_t *) (UIP_IP_BUF))[ndx]; LOG_DBG("%02x", data); } LOG_DBG("\n"); } #endif /* LOG_DBG_ENABLED */ hc06_ptr = PACKETBUF_IPHC_BUF + 2; /* * 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 = SICSLOWPAN_DISPATCH_IPHC; iphc1 = 0; PACKETBUF_IPHC_BUF[2] = 0; /* might not be used - but needs to be cleared */ /* * Address handling needs to be made first since it might * cause an extra byte with [ SCI | DCI ] * */ /* check if dest context exists (for allocating third byte) */ /* TODO: fix this so that it remembers the looked up values for avoiding two lookups - or set the lookup values immediately */ if(addr_context_lookup_by_prefix(&UIP_IP_BUF->destipaddr) != NULL || addr_context_lookup_by_prefix(&UIP_IP_BUF->srcipaddr) != NULL) { /* set context flag and increase hc06_ptr */ LOG_INFO("IPHC: compressing dest or src ipaddr - setting CID\n"); iphc1 |= SICSLOWPAN_IPHC_CID; hc06_ptr++; } /* * 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 */ /* IPHC format of tc is ECN | DSCP , original is DSCP | ECN */ tmp = (UIP_IP_BUF->vtc << 4) | (UIP_IP_BUF->tcflow >> 4); tmp = ((tmp & 0x03) << 6) | (tmp >> 2); if(((UIP_IP_BUF->tcflow & 0x0F) == 0) && (UIP_IP_BUF->flow == 0)) { /* flow label can be compressed */ iphc0 |= SICSLOWPAN_IPHC_FL_C; if(((UIP_IP_BUF->vtc & 0x0F) == 0) && ((UIP_IP_BUF->tcflow & 0xF0) == 0)) { /* compress (elide) all */ iphc0 |= SICSLOWPAN_IPHC_TC_C; } else { /* compress only the flow label */ *hc06_ptr = tmp; hc06_ptr += 1; } } else { /* Flow label cannot be compressed */ if(((UIP_IP_BUF->vtc & 0x0F) == 0) && ((UIP_IP_BUF->tcflow & 0xF0) == 0)) { /* compress only traffic class */ iphc0 |= SICSLOWPAN_IPHC_TC_C; *hc06_ptr = (tmp & 0xc0) | (UIP_IP_BUF->tcflow & 0x0F); memcpy(hc06_ptr + 1, &UIP_IP_BUF->flow, 2); hc06_ptr += 3; } else { /* compress nothing */ memcpy(hc06_ptr, &UIP_IP_BUF->vtc, 4); /* but replace the top byte with the new ECN | DSCP format*/ *hc06_ptr = tmp; hc06_ptr += 4; } } /* Note that the payload length is always compressed */ /* Next header. We compress it is compressable. */ if(IS_COMPRESSABLE_PROTO(UIP_IP_BUF->proto)) { iphc0 |= SICSLOWPAN_IPHC_NH_C; } /* Add proto header unless it is compressed */ if((iphc0 & SICSLOWPAN_IPHC_NH_C) == 0) { *hc06_ptr = UIP_IP_BUF->proto; 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(UIP_IP_BUF->ttl) { case 1: iphc0 |= SICSLOWPAN_IPHC_TTL_1; break; case 64: iphc0 |= SICSLOWPAN_IPHC_TTL_64; break; case 255: iphc0 |= SICSLOWPAN_IPHC_TTL_255; break; default: *hc06_ptr = UIP_IP_BUF->ttl; hc06_ptr += 1; break; } /* source address - cannot be multicast */ if(uip_is_addr_unspecified(&UIP_IP_BUF->srcipaddr)) { LOG_INFO("IPHC: compressing unspecified - setting SAC\n"); iphc1 |= SICSLOWPAN_IPHC_SAC; iphc1 |= SICSLOWPAN_IPHC_SAM_00; } else if((context = addr_context_lookup_by_prefix(&UIP_IP_BUF->srcipaddr)) != NULL) { /* elide the prefix - indicate by CID and set context + SAC */ LOG_INFO("IPHC: compressing src with context - setting CID & SAC ctx: %d\n", context->number); iphc1 |= SICSLOWPAN_IPHC_CID | SICSLOWPAN_IPHC_SAC; PACKETBUF_IPHC_BUF[2] |= context->number << 4; /* compession compare with this nodes address (source) */ iphc1 |= compress_addr_64(SICSLOWPAN_IPHC_SAM_BIT, &UIP_IP_BUF->srcipaddr, &uip_lladdr); /* No context found for this address */ } else if(uip_is_addr_linklocal(&UIP_IP_BUF->srcipaddr) && UIP_IP_BUF->destipaddr.u16[1] == 0 && UIP_IP_BUF->destipaddr.u16[2] == 0 && UIP_IP_BUF->destipaddr.u16[3] == 0) { iphc1 |= compress_addr_64(SICSLOWPAN_IPHC_SAM_BIT, &UIP_IP_BUF->srcipaddr, &uip_lladdr); } else { /* send the full address => SAC = 0, SAM = 00 */ iphc1 |= SICSLOWPAN_IPHC_SAM_00; /* 128-bits */ memcpy(hc06_ptr, &UIP_IP_BUF->srcipaddr.u16[0], 16); hc06_ptr += 16; } /* dest address*/ if(uip_is_addr_mcast(&UIP_IP_BUF->destipaddr)) { /* Address is multicast, try to compress */ iphc1 |= SICSLOWPAN_IPHC_M; if(sicslowpan_is_mcast_addr_compressable8(&UIP_IP_BUF->destipaddr)) { iphc1 |= SICSLOWPAN_IPHC_DAM_11; /* use last byte */ *hc06_ptr = UIP_IP_BUF->destipaddr.u8[15]; hc06_ptr += 1; } else if(sicslowpan_is_mcast_addr_compressable32(&UIP_IP_BUF->destipaddr)) { iphc1 |= SICSLOWPAN_IPHC_DAM_10; /* second byte + the last three */ *hc06_ptr = UIP_IP_BUF->destipaddr.u8[1]; memcpy(hc06_ptr + 1, &UIP_IP_BUF->destipaddr.u8[13], 3); hc06_ptr += 4; } else if(sicslowpan_is_mcast_addr_compressable48(&UIP_IP_BUF->destipaddr)) { iphc1 |= SICSLOWPAN_IPHC_DAM_01; /* second byte + the last five */ *hc06_ptr = UIP_IP_BUF->destipaddr.u8[1]; memcpy(hc06_ptr + 1, &UIP_IP_BUF->destipaddr.u8[11], 5); hc06_ptr += 6; } else { iphc1 |= SICSLOWPAN_IPHC_DAM_00; /* full address */ memcpy(hc06_ptr, &UIP_IP_BUF->destipaddr.u8[0], 16); hc06_ptr += 16; } } else { /* Address is unicast, try to compress */ if((context = addr_context_lookup_by_prefix(&UIP_IP_BUF->destipaddr)) != NULL) { /* elide the prefix */ iphc1 |= SICSLOWPAN_IPHC_DAC; PACKETBUF_IPHC_BUF[2] |= context->number; /* compession compare with link adress (destination) */ iphc1 |= compress_addr_64(SICSLOWPAN_IPHC_DAM_BIT, &UIP_IP_BUF->destipaddr, (uip_lladdr_t *)link_destaddr); /* No context found for this address */ } else if(uip_is_addr_linklocal(&UIP_IP_BUF->destipaddr) && UIP_IP_BUF->destipaddr.u16[1] == 0 && UIP_IP_BUF->destipaddr.u16[2] == 0 && UIP_IP_BUF->destipaddr.u16[3] == 0) { iphc1 |= compress_addr_64(SICSLOWPAN_IPHC_DAM_BIT, &UIP_IP_BUF->destipaddr, (uip_lladdr_t *)link_destaddr); } else { /* send the full address */ iphc1 |= SICSLOWPAN_IPHC_DAM_00; /* 128-bits */ memcpy(hc06_ptr, &UIP_IP_BUF->destipaddr.u16[0], 16); hc06_ptr += 16; } } uncomp_hdr_len = UIP_IPH_LEN; /* Start of ext hdr compression or UDP compression */ /* pick out the next-header position */ next_hdr = &UIP_IP_BUF->proto; next_nhc = hc06_ptr; /* here we set the next header is compressed. */ ext_hdr_len = 0; /* reserve the write place of this next header position */ LOG_INFO("Compressing first header: %d\n", *next_hdr); while(next_hdr != NULL && IS_COMPRESSABLE_PROTO(*next_hdr)) { LOG_INFO("Compressing next header: %d\n", *next_hdr); int proto = -1; /* used for the specific ext hdr */ /* UDP and EXT header compression */ switch(*next_hdr) { case UIP_PROTO_HBHO: proto = SICSLOWPAN_NHC_ETX_HDR_HBHO; case UIP_PROTO_ROUTING: proto = proto == -1 ? SICSLOWPAN_NHC_ETX_HDR_ROUTING : proto; case UIP_PROTO_FRAG: proto = proto == -1 ? SICSLOWPAN_NHC_ETX_HDR_FRAG : proto; case UIP_PROTO_DESTO: /* Handle the header here! */ { struct uip_ext_hdr *ext_hdr = (struct uip_ext_hdr *) UIP_IPPAYLOAD_BUF(ext_hdr_len); int len; proto = proto == -1 ? SICSLOWPAN_NHC_ETX_HDR_DESTO : proto; /* Len is defined to be in octets from the length byte */ len = (ext_hdr->len << 3) + 8; LOG_INFO("Handling next header: %d (len:%d)\n", *next_hdr, len); /* pick up the next header */ next_hdr = &ext_hdr->next; /* If the next header is not compressable we need to reserve the NHC byte extra - before the next header here. This is due to next not being elided in that case. */ if(!IS_COMPRESSABLE_PROTO(*next_hdr)) { hc06_ptr++; LOG_INFO("Keeping the next header in this ext hdr: %d\n", ext_hdr->next); } /* copy the ext-hdr into the hc06 buffer */ memcpy(hc06_ptr, ext_hdr, len); /* modify the len to octets */ ext_hdr = (struct uip_ext_hdr *) hc06_ptr; ext_hdr->len = len - 2; /* Len should be in bytes from len byte*/ ext_hdr_len += len; hc06_ptr += len; uncomp_hdr_len += len; /* Write this next header - with its NHC header - including flag to tell if next header is elided in this one also- */ *next_nhc = SICSLOWPAN_NHC_EXT_HDR | (IS_COMPRESSABLE_PROTO(*next_hdr) ? SICSLOWPAN_NHC_BIT : 0) | (proto << 1); /* update the position of the next header */ next_nhc = hc06_ptr; } break; case UIP_PROTO_UDP: /* allocate a byte for the next header posision as UDP has no next */ hc06_ptr++; udp_buf = UIP_UDP_BUF(ext_hdr_len); LOG_INFO("IPHC: Uncompressed UDP ports on send side: %x, %x\n", UIP_HTONS(udp_buf->srcport), UIP_HTONS(udp_buf->destport)); /* Mask out the last 4 bits can be used as a mask */ if(((UIP_HTONS(udp_buf->srcport) & 0xfff0) == SICSLOWPAN_UDP_4_BIT_PORT_MIN) && ((UIP_HTONS(udp_buf->destport) & 0xfff0) == SICSLOWPAN_UDP_4_BIT_PORT_MIN)) { /* we can compress 12 bits of both source and dest */ *next_nhc = SICSLOWPAN_NHC_UDP_CS_P_11; LOG_INFO("IPHC: remove 12 b of both source & dest with prefix 0xFOB\n"); *hc06_ptr = (uint8_t)((UIP_HTONS(udp_buf->srcport) - SICSLOWPAN_UDP_4_BIT_PORT_MIN) << 4) + (uint8_t)((UIP_HTONS(udp_buf->destport) - SICSLOWPAN_UDP_4_BIT_PORT_MIN)); hc06_ptr += 1; } else if((UIP_HTONS(udp_buf->destport) & 0xff00) == SICSLOWPAN_UDP_8_BIT_PORT_MIN) { /* we can compress 8 bits of dest, leave source. */ *next_nhc = SICSLOWPAN_NHC_UDP_CS_P_01; LOG_INFO("IPHC: leave source, remove 8 bits of dest with prefix 0xF0\n"); memcpy(hc06_ptr, &udp_buf->srcport, 2); *(hc06_ptr + 2) = (uint8_t)((UIP_HTONS(udp_buf->destport) - SICSLOWPAN_UDP_8_BIT_PORT_MIN)); hc06_ptr += 3; } else if((UIP_HTONS(udp_buf->srcport) & 0xff00) == SICSLOWPAN_UDP_8_BIT_PORT_MIN) { /* we can compress 8 bits of src, leave dest. Copy compressed port */ *next_nhc = SICSLOWPAN_NHC_UDP_CS_P_10; LOG_INFO("IPHC: remove 8 bits of source with prefix 0xF0, leave dest. hch: %i\n", *next_nhc); *hc06_ptr = (uint8_t)((UIP_HTONS(udp_buf->srcport) - SICSLOWPAN_UDP_8_BIT_PORT_MIN)); memcpy(hc06_ptr + 1, &udp_buf->destport, 2); hc06_ptr += 3; } else { /* we cannot compress. Copy uncompressed ports, full checksum */ *next_nhc = SICSLOWPAN_NHC_UDP_CS_P_00; LOG_INFO("IPHC: cannot compress UDP headers\n"); memcpy(hc06_ptr, &udp_buf->srcport, 4); hc06_ptr += 4; } /* always inline the checksum */ memcpy(hc06_ptr, &udp_buf->udpchksum, 2); hc06_ptr += 2; uncomp_hdr_len += UIP_UDPH_LEN; /* this is the final header... */ next_hdr = NULL; break; default: LOG_ERR("IPHC: could not handle compression of header"); } } if(next_hdr != NULL) { /* Last header could not be compressed - we assume that this is then OK!*/ /* as the last EXT_HDR should be "uncompressed" and have the next there */ LOG_INFO("IPHC: last header could is not compressed: %d\n", *next_hdr); } /* before the packetbuf_hdr_len operation */ PACKETBUF_IPHC_BUF[0] = iphc0; PACKETBUF_IPHC_BUF[1] = iphc1; #if LOG_DBG_ENABLED { uint16_t ndx; LOG_DBG("after compression %d: ", (int)(hc06_ptr - packetbuf_ptr)); for(ndx = 0; ndx < hc06_ptr - packetbuf_ptr; ndx++) { uint8_t data = ((uint8_t *) packetbuf_ptr)[ndx]; LOG_DBG("%02x", data); } LOG_DBG("\n"); } #endif packetbuf_hdr_len = hc06_ptr - packetbuf_ptr; } /*--------------------------------------------------------------------*/ /** * \brief Uncompress IPHC (i.e., IPHC and LOWPAN_UDP) headers and put * them in sicslowpan_buf * * This function is called by the input function when the dispatch is * IPHC. * We %process the packet in the packetbuf buffer, uncompress the header * fields, and copy the result in the sicslowpan buffer. * At the end of the decompression, packetbuf_hdr_len and uncompressed_hdr_len * are set to the appropriate values * * \param buf Pointer to the buffer to uncompress the packet into. * \param ip_len Equal to 0 if the packet is not a fragment (IP length * is then inferred from the L2 length), non 0 if the packet is a 1st * fragment. */ static void uncompress_hdr_iphc(uint8_t *buf, uint16_t ip_len) { uint8_t tmp, iphc0, iphc1, nhc; struct uip_ext_hdr *exthdr; uint8_t* last_nextheader; uint8_t* ip_payload; uint8_t ext_hdr_len = 0; /* at least two byte will be used for the encoding */ hc06_ptr = packetbuf_ptr + packetbuf_hdr_len + 2; iphc0 = PACKETBUF_IPHC_BUF[0]; iphc1 = PACKETBUF_IPHC_BUF[1]; /* another if the CID flag is set */ if(iphc1 & SICSLOWPAN_IPHC_CID) { LOG_INFO("IPHC: CID flag set - increase header with one\n"); hc06_ptr++; } /* Traffic class and flow label */ if((iphc0 & SICSLOWPAN_IPHC_FL_C) == 0) { /* Flow label are carried inline */ if((iphc0 & SICSLOWPAN_IPHC_TC_C) == 0) { /* Traffic class is carried inline */ memcpy(&SICSLOWPAN_IP_BUF(buf)->tcflow, hc06_ptr + 1, 3); tmp = *hc06_ptr; hc06_ptr += 4; /* IPHC format of tc is ECN | DSCP , original is DSCP | ECN */ /* set version, pick highest DSCP bits and set in vtc */ SICSLOWPAN_IP_BUF(buf)->vtc = 0x60 | ((tmp >> 2) & 0x0f); /* ECN rolled down two steps + lowest DSCP bits at top two bits */ SICSLOWPAN_IP_BUF(buf)->tcflow = ((tmp >> 2) & 0x30) | (tmp << 6) | (SICSLOWPAN_IP_BUF(buf)->tcflow & 0x0f); } else { /* Traffic class is compressed (set version and no TC)*/ SICSLOWPAN_IP_BUF(buf)->vtc = 0x60; /* highest flow label bits + ECN bits */ SICSLOWPAN_IP_BUF(buf)->tcflow = (*hc06_ptr & 0x0F) | ((*hc06_ptr >> 2) & 0x30); memcpy(&SICSLOWPAN_IP_BUF(buf)->flow, hc06_ptr + 1, 2); hc06_ptr += 3; } } else { /* Version is always 6! */ /* Version and flow label are compressed */ if((iphc0 & SICSLOWPAN_IPHC_TC_C) == 0) { /* Traffic class is inline */ SICSLOWPAN_IP_BUF(buf)->vtc = 0x60 | ((*hc06_ptr >> 2) & 0x0f); SICSLOWPAN_IP_BUF(buf)->tcflow = ((*hc06_ptr << 6) & 0xC0) | ((*hc06_ptr >> 2) & 0x30); SICSLOWPAN_IP_BUF(buf)->flow = 0; hc06_ptr += 1; } else { /* Traffic class is compressed */ SICSLOWPAN_IP_BUF(buf)->vtc = 0x60; SICSLOWPAN_IP_BUF(buf)->tcflow = 0; SICSLOWPAN_IP_BUF(buf)->flow = 0; } } /* Next Header */ if((iphc0 & SICSLOWPAN_IPHC_NH_C) == 0) { /* Next header is carried inline */ SICSLOWPAN_IP_BUF(buf)->proto = *hc06_ptr; LOG_INFO("IPHC: next header inline: %d\n", SICSLOWPAN_IP_BUF(buf)->proto); hc06_ptr += 1; } /* Hop limit */ if((iphc0 & 0x03) != SICSLOWPAN_IPHC_TTL_I) { SICSLOWPAN_IP_BUF(buf)->ttl = ttl_values[iphc0 & 0x03]; } else { SICSLOWPAN_IP_BUF(buf)->ttl = *hc06_ptr; hc06_ptr += 1; } /* put the source address compression mode SAM in the tmp var */ tmp = ((iphc1 & SICSLOWPAN_IPHC_SAM_11) >> SICSLOWPAN_IPHC_SAM_BIT) & 0x03; /* context based compression */ if(iphc1 & SICSLOWPAN_IPHC_SAC) { uint8_t sci = (iphc1 & SICSLOWPAN_IPHC_CID) ? PACKETBUF_IPHC_BUF[2] >> 4 : 0; /* Source address - check context != NULL only if SAM bits are != 0*/ if (tmp != 0) { context = addr_context_lookup_by_number(sci); if(context == NULL) { LOG_ERR("uncompress_hdr: error context not found\n"); return; } } /* if tmp == 0 we do not have a context and therefore no prefix */ uncompress_addr(&SICSLOWPAN_IP_BUF(buf)->srcipaddr, tmp != 0 ? context->prefix : NULL, unc_ctxconf[tmp], (uip_lladdr_t *)packetbuf_addr(PACKETBUF_ADDR_SENDER)); } else { /* no compression and link local */ uncompress_addr(&SICSLOWPAN_IP_BUF(buf)->srcipaddr, llprefix, unc_llconf[tmp], (uip_lladdr_t *)packetbuf_addr(PACKETBUF_ADDR_SENDER)); } /* Destination address */ /* put the destination address compression mode into tmp */ tmp = ((iphc1 & SICSLOWPAN_IPHC_DAM_11) >> SICSLOWPAN_IPHC_DAM_BIT) & 0x03; /* multicast compression */ if(iphc1 & SICSLOWPAN_IPHC_M) { /* context based multicast compression */ if(iphc1 & SICSLOWPAN_IPHC_DAC) { /* TODO: implement this */ } else { /* non-context based multicast compression - */ /* DAM_00: 128 bits */ /* DAM_01: 48 bits FFXX::00XX:XXXX:XXXX */ /* DAM_10: 32 bits FFXX::00XX:XXXX */ /* DAM_11: 8 bits FF02::00XX */ uint8_t prefix[] = {0xff, 0x02}; if(tmp > 0 && tmp < 3) { prefix[1] = *hc06_ptr; hc06_ptr++; } uncompress_addr(&SICSLOWPAN_IP_BUF(buf)->destipaddr, prefix, unc_mxconf[tmp], NULL); } } else { /* no multicast */ /* Context based */ if(iphc1 & SICSLOWPAN_IPHC_DAC) { uint8_t dci = (iphc1 & SICSLOWPAN_IPHC_CID) ? PACKETBUF_IPHC_BUF[2] & 0x0f : 0; context = addr_context_lookup_by_number(dci); /* all valid cases below need the context! */ if(context == NULL) { LOG_ERR("uncompress_hdr: error context not found\n"); return; } uncompress_addr(&SICSLOWPAN_IP_BUF(buf)->destipaddr, context->prefix, unc_ctxconf[tmp], (uip_lladdr_t *)packetbuf_addr(PACKETBUF_ADDR_RECEIVER)); } else { /* not context based => link local M = 0, DAC = 0 - same as SAC */ uncompress_addr(&SICSLOWPAN_IP_BUF(buf)->destipaddr, llprefix, unc_llconf[tmp], (uip_lladdr_t *)packetbuf_addr(PACKETBUF_ADDR_RECEIVER)); } } uncomp_hdr_len += UIP_IPH_LEN; /* Next header processing - continued */ nhc = iphc0 & SICSLOWPAN_IPHC_NH_C; /* The next header is compressed, NHC is following */ last_nextheader = &SICSLOWPAN_IP_BUF(buf)->proto; ip_payload = SICSLOWPAN_IPPAYLOAD_BUF(buf); while(nhc && (*hc06_ptr & SICSLOWPAN_NHC_MASK) == SICSLOWPAN_NHC_EXT_HDR) { uint8_t eid = (*hc06_ptr & 0x0e) >> 1; /* next header compression flag */ uint8_t nh = (*hc06_ptr & 0x01); uint8_t next = 0; uint8_t len; uint8_t proto; nhc = nh; hc06_ptr++; if(!nh) { next = *hc06_ptr; hc06_ptr++; LOG_INFO("Next header is not compressed... next: %d\n", next); } len = *hc06_ptr; hc06_ptr++; LOG_INFO("IPHC: Found extension-header id=%d next=%d len=%d\n", eid, next, len); switch(eid) { case SICSLOWPAN_NHC_ETX_HDR_HBHO: proto = UIP_PROTO_HBHO; break; case SICSLOWPAN_NHC_ETX_HDR_ROUTING: proto = UIP_PROTO_ROUTING; break; case SICSLOWPAN_NHC_ETX_HDR_FRAG: proto = UIP_PROTO_FRAG; break; case SICSLOWPAN_NHC_ETX_HDR_DESTO: proto = UIP_PROTO_DESTO; break; default: LOG_INFO("IPHC: error unsupported extension-header\n"); return; } *last_nextheader = proto; /* uncompress the extension header */ exthdr = (struct uip_ext_hdr *)ip_payload; exthdr->len = (2 + len) / 8 - 1; exthdr->next = next; last_nextheader = &exthdr->next; memcpy((uint8_t*)exthdr + 2, hc06_ptr, len); hc06_ptr += len; uncomp_hdr_len += (exthdr->len + 1) * 8; ip_payload += (exthdr->len + 1) * 8; ext_hdr_len += (exthdr->len + 1) * 8; LOG_INFO("Uncompressed EXT hdr: %d len:%d exhdrlen:%d (calc: %d)\n", proto, len, exthdr->len, (exthdr->len + 1) * 8); } /* The next header is compressed, NHC is following */ if(nhc && (*hc06_ptr & SICSLOWPAN_NHC_UDP_MASK) == SICSLOWPAN_NHC_UDP_ID) { struct uip_udp_hdr *udp_buf = (struct uip_udp_hdr *)ip_payload; uint16_t udp_len; uint8_t checksum_compressed; *last_nextheader = UIP_PROTO_UDP; checksum_compressed = *hc06_ptr & SICSLOWPAN_NHC_UDP_CHECKSUMC; LOG_INFO("IPHC: Incoming header value: %i\n", *hc06_ptr); switch(*hc06_ptr & SICSLOWPAN_NHC_UDP_CS_P_11) { case SICSLOWPAN_NHC_UDP_CS_P_00: /* 1 byte for NHC, 4 byte for ports, 2 bytes chksum */ memcpy(&udp_buf->srcport, hc06_ptr + 1, 2); memcpy(&udp_buf->destport, hc06_ptr + 3, 2); LOG_INFO("IPHC: Uncompressed UDP ports (ptr+5): %x, %x\n", UIP_HTONS(udp_buf->srcport), UIP_HTONS(udp_buf->destport)); hc06_ptr += 5; break; case SICSLOWPAN_NHC_UDP_CS_P_01: /* 1 byte for NHC + source 16bit inline, dest = 0xF0 + 8 bit inline */ LOG_INFO("IPHC: Decompressing destination\n"); memcpy(&udp_buf->srcport, hc06_ptr + 1, 2); udp_buf->destport = UIP_HTONS(SICSLOWPAN_UDP_8_BIT_PORT_MIN + (*(hc06_ptr + 3))); LOG_INFO("IPHC: Uncompressed UDP ports (ptr+4): %x, %x\n", UIP_HTONS(udp_buf->srcport), UIP_HTONS(udp_buf->destport)); hc06_ptr += 4; break; case SICSLOWPAN_NHC_UDP_CS_P_10: /* 1 byte for NHC + source = 0xF0 + 8bit inline, dest = 16 bit inline*/ LOG_INFO("IPHC: Decompressing source\n"); udp_buf->srcport = UIP_HTONS(SICSLOWPAN_UDP_8_BIT_PORT_MIN + (*(hc06_ptr + 1))); memcpy(&udp_buf->destport, hc06_ptr + 2, 2); LOG_INFO("IPHC: Uncompressed UDP ports (ptr+4): %x, %x\n", UIP_HTONS(udp_buf->srcport), UIP_HTONS(udp_buf->destport)); hc06_ptr += 4; break; case SICSLOWPAN_NHC_UDP_CS_P_11: /* 1 byte for NHC, 1 byte for ports */ udp_buf->srcport = UIP_HTONS(SICSLOWPAN_UDP_4_BIT_PORT_MIN + (*(hc06_ptr + 1) >> 4)); udp_buf->destport = UIP_HTONS(SICSLOWPAN_UDP_4_BIT_PORT_MIN + ((*(hc06_ptr + 1)) & 0x0F)); LOG_INFO("IPHC: Uncompressed UDP ports (ptr+2): %x, %x\n", UIP_HTONS(udp_buf->srcport), UIP_HTONS(udp_buf->destport)); hc06_ptr += 2; break; default: LOG_INFO("sicslowpan uncompress_hdr: error unsupported UDP compression\n"); return; } if(!checksum_compressed) { /* has_checksum, default */ memcpy(&udp_buf->udpchksum, hc06_ptr, 2); hc06_ptr += 2; LOG_INFO("IPHC: sicslowpan uncompress_hdr: checksum included\n"); } else { LOG_INFO("IPHC: sicslowpan uncompress_hdr: checksum *NOT* included\n"); } /* length field in UDP header (8 byte header + payload) */ udp_len = 8 + packetbuf_datalen() - (hc06_ptr - packetbuf_ptr); udp_buf->udplen = UIP_HTONS(ip_len == 0 ? udp_len : ip_len - UIP_IPH_LEN - ext_hdr_len); LOG_INFO("Setting UDP length: %u (ext: %u) ip_len: %d udp_len:%d\n", UIP_HTONS(udp_buf->udplen), ext_hdr_len, ip_len, udp_len); uncomp_hdr_len += UIP_UDPH_LEN; } packetbuf_hdr_len = hc06_ptr - packetbuf_ptr; /* IP length field. */ if(ip_len == 0) { int len = packetbuf_datalen() - packetbuf_hdr_len + uncomp_hdr_len - UIP_IPH_LEN; LOG_INFO("IP payload length: %d. %u - %u + %u - %u\n", len, packetbuf_datalen(), packetbuf_hdr_len, uncomp_hdr_len, UIP_IPH_LEN); /* This is not a fragmented packet */ SICSLOWPAN_IP_BUF(buf)->len[0] = len >> 8; SICSLOWPAN_IP_BUF(buf)->len[1] = len & 0x00FF; } else { /* This is a 1st fragment */ SICSLOWPAN_IP_BUF(buf)->len[0] = (ip_len - UIP_IPH_LEN) >> 8; SICSLOWPAN_IP_BUF(buf)->len[1] = (ip_len - UIP_IPH_LEN) & 0x00FF; } } /** @} */ #endif /* SICSLOWPAN_COMPRESSION >= SICSLOWPAN_COMPRESSION_IPHC */ #if SICSLOWPAN_COMPRESSION == SICSLOWPAN_COMPRESSION_6LORH /*--------------------------------------------------------------------*/ /** * \brief Adds Paging dispatch byte */ static void add_paging_dispatch(uint8_t page) { /* Add paging dispatch to Page 1 */ PACKETBUF_6LO_PTR[PACKETBUF_6LO_DISPATCH] = SICSLOWPAN_DISPATCH_PAGING | (page & 0x0f); packetbuf_hdr_len++; } /*--------------------------------------------------------------------*/ /** * \brief Adds 6lorh headers before IPHC */ static void add_6lorh_hdr(void) { /* 6LoRH is not implemented yet */ } #endif /* SICSLOWPAN_COMPRESSION == SICSLOWPAN_COMPRESSION_6LORH */ /*--------------------------------------------------------------------*/ /** * \brief Digest 6lorh headers before IPHC */ static void digest_paging_dispatch(void) { /* Is this a paging dispatch? */ if((PACKETBUF_6LO_PTR[PACKETBUF_6LO_DISPATCH] & SICSLOWPAN_DISPATCH_PAGING_MASK) == SICSLOWPAN_DISPATCH_PAGING) { /* Parse page number */ curr_page = PACKETBUF_6LO_PTR[PACKETBUF_6LO_DISPATCH] & 0x0f; packetbuf_hdr_len++; } } /*--------------------------------------------------------------------*/ /** * \brief Digest 6lorh headers before IPHC */ static void digest_6lorh_hdr(void) { /* 6LoRH is not implemented yet */ } /*--------------------------------------------------------------------*/ /** \name IPv6 dispatch "compression" function * @{ */ /*--------------------------------------------------------------------*/ /* \brief Packets "Compression" when only IPv6 dispatch is used * * There is no compression in this case, all fields are sent * inline. We just add the IPv6 dispatch byte before the packet. * \verbatim * 0 1 2 3 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * | IPv6 Dsp | IPv6 header and payload ... * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * \endverbatim */ #if SICSLOWPAN_COMPRESSION == SICSLOWPAN_COMPRESSION_IPV6 static void compress_hdr_ipv6(linkaddr_t *link_destaddr) { *packetbuf_ptr = SICSLOWPAN_DISPATCH_IPV6; packetbuf_hdr_len += SICSLOWPAN_IPV6_HDR_LEN; memcpy(packetbuf_ptr + packetbuf_hdr_len, UIP_IP_BUF, UIP_IPH_LEN); packetbuf_hdr_len += UIP_IPH_LEN; uncomp_hdr_len += UIP_IPH_LEN; return; } #endif /* SICSLOWPAN_COMPRESSION == SICSLOWPAN_COMPRESSION_IPV6 */ /** @} */ /*--------------------------------------------------------------------*/ /** \name Input/output functions common to all compression schemes * @{ */ /*--------------------------------------------------------------------*/ /** * Callback function for the MAC packet sent callback */ static void packet_sent(void *ptr, int status, int transmissions) { const linkaddr_t *dest; if(callback != NULL) { callback->output_callback(status); } last_tx_status = status; /* What follows only applies to unicast */ dest = packetbuf_addr(PACKETBUF_ADDR_RECEIVER); if(linkaddr_cmp(dest, &linkaddr_null)) { return; } /* Update neighbor link statistics */ link_stats_packet_sent(dest, status, transmissions); #if UIP_CONF_IPV6_RPL /* Call RPL link callback */ rpl_link_callback(dest, status, transmissions); #endif /* UIP_CONF_IPV6_RPL */ /* DS6 callback, used for UIP_DS6_LL_NUD */ uip_ds6_link_callback(status, transmissions); } /*--------------------------------------------------------------------*/ /** * \brief This function is called by the 6lowpan code to send out a * packet. * \param dest the link layer destination address of the packet */ static void send_packet(linkaddr_t *dest) { /* Set the link layer destination address for the packet as a * packetbuf attribute. The MAC layer can access the destination * address with the function packetbuf_addr(PACKETBUF_ADDR_RECEIVER). */ packetbuf_set_addr(PACKETBUF_ADDR_RECEIVER, dest); #if NETSTACK_CONF_BRIDGE_MODE /* This needs to be explicitly set here for bridge mode to work */ packetbuf_set_addr(PACKETBUF_ADDR_SENDER,(void*)&uip_lladdr); #endif /* Provide a callback function to receive the result of a packet transmission. */ NETSTACK_MAC.send(&packet_sent, NULL); /* If we are sending multiple packets in a row, we need to let the watchdog know that we are still alive. */ watchdog_periodic(); } /*--------------------------------------------------------------------*/ /** \brief Take an IP packet and format it to be sent on an 802.15.4 * network using 6lowpan. * \param localdest The MAC address of the destination * * The IP packet is initially in uip_buf. Its header is compressed * and if necessary it is fragmented. The resulting * packet/fragments are put in packetbuf and delivered to the 802.15.4 * MAC. */ static uint8_t output(const uip_lladdr_t *localdest) { int framer_hdrlen; int max_payload; /* The MAC address of the destination of the packet */ linkaddr_t dest; /* init */ uncomp_hdr_len = 0; packetbuf_hdr_len = 0; /* reset packetbuf buffer */ packetbuf_clear(); packetbuf_ptr = packetbuf_dataptr(); if(callback) { /* call the attribution when the callback comes, but set attributes here ! */ set_packet_attrs(); } /* * The destination address will be tagged to each outbound * packet. If the argument localdest is NULL, we are sending a * broadcast packet. */ if(localdest == NULL) { linkaddr_copy(&dest, &linkaddr_null); } else { linkaddr_copy(&dest, (const linkaddr_t *)localdest); } LOG_INFO("output: sending packet len %d\n", uip_len); /* Try to compress the headers */ #if SICSLOWPAN_COMPRESSION == SICSLOWPAN_COMPRESSION_IPV6 compress_hdr_ipv6(&dest); #endif /* SICSLOWPAN_COMPRESSION == SICSLOWPAN_COMPRESSION_IPV6 */ #if SICSLOWPAN_COMPRESSION == SICSLOWPAN_COMPRESSION_6LORH /* Add 6LoRH headers before IPHC. Only needed on routed traffic (non link-local). */ if(!uip_is_addr_linklocal(&UIP_IP_BUF->destipaddr)) { add_paging_dispatch(1); add_6lorh_hdr(); } #endif /* SICSLOWPAN_COMPRESSION == SICSLOWPAN_COMPRESSION_6LORH */ #if SICSLOWPAN_COMPRESSION >= SICSLOWPAN_COMPRESSION_IPHC compress_hdr_iphc(&dest); #endif /* SICSLOWPAN_COMPRESSION >= SICSLOWPAN_COMPRESSION_IPHC */ LOG_INFO("output: header of len %d\n", packetbuf_hdr_len); /* Calculate NETSTACK_FRAMER's header length, that will be added in the NETSTACK_MAC. * We calculate it here only to make a better decision of whether the outgoing packet * needs to be fragmented or not. */ #ifndef SICSLOWPAN_USE_FIXED_HDRLEN packetbuf_set_addr(PACKETBUF_ADDR_RECEIVER, &dest); framer_hdrlen = NETSTACK_FRAMER.length(); if(framer_hdrlen < 0) { /* Framing failed, we assume the maximum header length */ framer_hdrlen = SICSLOWPAN_FIXED_HDRLEN; } #else /* USE_FRAMER_HDRLEN */ framer_hdrlen = SICSLOWPAN_FIXED_HDRLEN; #endif /* USE_FRAMER_HDRLEN */ max_payload = MAC_MAX_PAYLOAD - framer_hdrlen; if((int)uip_len - (int)uncomp_hdr_len > max_payload - (int)packetbuf_hdr_len) { #if SICSLOWPAN_CONF_FRAG /* Number of bytes processed. */ uint16_t processed_ip_out_len; struct queuebuf *q; uint16_t frag_tag; /* * The outbound IPv6 packet is too large to fit into a single 15.4 * packet, so we fragment it into multiple packets and send them. * The first fragment contains frag1 dispatch, then * IPv6/IPHC/HC_UDP dispatchs/headers. * The following fragments contain only the fragn dispatch. */ int estimated_fragments = ((int)uip_len) / (max_payload - SICSLOWPAN_FRAGN_HDR_LEN) + 1; int freebuf = queuebuf_numfree() - 1; LOG_INFO("uip_len: %d, fragments: %d, free bufs: %d\n", uip_len, estimated_fragments, freebuf); if(freebuf < estimated_fragments) { LOG_WARN("Dropping packet, not enough free bufs\n"); return 0; } LOG_INFO("Fragmentation sending packet len %d\n", uip_len); /* Create 1st Fragment */ LOG_INFO("output: 1rst fragment "); /* Reset last tx status to ok in case the fragment transmissions are deferred */ last_tx_status = MAC_TX_OK; /* move IPHC/IPv6 header */ memmove(packetbuf_ptr + SICSLOWPAN_FRAG1_HDR_LEN, packetbuf_ptr, packetbuf_hdr_len); /* * FRAG1 dispatch + header * Note that the length is in units of 8 bytes */ SET16(PACKETBUF_FRAG_PTR, PACKETBUF_FRAG_DISPATCH_SIZE, ((SICSLOWPAN_DISPATCH_FRAG1 << 8) | uip_len)); frag_tag = my_tag++; SET16(PACKETBUF_FRAG_PTR, PACKETBUF_FRAG_TAG, frag_tag); /* Copy payload and send */ packetbuf_hdr_len += SICSLOWPAN_FRAG1_HDR_LEN; packetbuf_payload_len = (max_payload - packetbuf_hdr_len) & 0xfffffff8; LOG_INFO("(len %d, tag %d)\n", packetbuf_payload_len, frag_tag); memcpy(packetbuf_ptr + packetbuf_hdr_len, (uint8_t *)UIP_IP_BUF + uncomp_hdr_len, packetbuf_payload_len); packetbuf_set_datalen(packetbuf_payload_len + packetbuf_hdr_len); q = queuebuf_new_from_packetbuf(); if(q == NULL) { LOG_WARN("could not allocate queuebuf for first fragment, dropping packet\n"); return 0; } send_packet(&dest); queuebuf_to_packetbuf(q); queuebuf_free(q); q = NULL; /* Check tx result. */ if((last_tx_status == MAC_TX_COLLISION) || (last_tx_status == MAC_TX_ERR) || (last_tx_status == MAC_TX_ERR_FATAL)) { LOG_ERR("error in fragment tx, dropping subsequent fragments.\n"); return 0; } /* set processed_ip_out_len to what we already sent from the IP payload*/ processed_ip_out_len = packetbuf_payload_len + uncomp_hdr_len; /* * Create following fragments * Datagram tag is already in the buffer, we need to set the * FRAGN dispatch and for each fragment, the offset */ packetbuf_hdr_len = SICSLOWPAN_FRAGN_HDR_LEN; /* PACKETBUF_FRAG_BUF->dispatch_size = */ /* uip_htons((SICSLOWPAN_DISPATCH_FRAGN << 8) | uip_len); */ SET16(PACKETBUF_FRAG_PTR, PACKETBUF_FRAG_DISPATCH_SIZE, ((SICSLOWPAN_DISPATCH_FRAGN << 8) | uip_len)); packetbuf_payload_len = (max_payload - packetbuf_hdr_len) & 0xfffffff8; while(processed_ip_out_len < uip_len) { LOG_INFO("output: fragment "); PACKETBUF_FRAG_PTR[PACKETBUF_FRAG_OFFSET] = processed_ip_out_len >> 3; /* Copy payload and send */ if(uip_len - processed_ip_out_len < packetbuf_payload_len) { /* last fragment */ packetbuf_payload_len = uip_len - processed_ip_out_len; } LOG_INFO("(offset %d, len %d, tag %d)\n", processed_ip_out_len >> 3, packetbuf_payload_len, frag_tag); memcpy(packetbuf_ptr + packetbuf_hdr_len, (uint8_t *)UIP_IP_BUF + processed_ip_out_len, packetbuf_payload_len); packetbuf_set_datalen(packetbuf_payload_len + packetbuf_hdr_len); q = queuebuf_new_from_packetbuf(); if(q == NULL) { LOG_WARN("could not allocate queuebuf, dropping fragment\n"); return 0; } send_packet(&dest); queuebuf_to_packetbuf(q); queuebuf_free(q); q = NULL; processed_ip_out_len += packetbuf_payload_len; /* Check tx result. */ if((last_tx_status == MAC_TX_COLLISION) || (last_tx_status == MAC_TX_ERR) || (last_tx_status == MAC_TX_ERR_FATAL)) { LOG_ERR("error in fragment tx, dropping subsequent fragments.\n"); return 0; } } #else /* SICSLOWPAN_CONF_FRAG */ LOG_ERR("output: Packet too large to be sent without fragmentation support; dropping packet\n"); return 0; #endif /* SICSLOWPAN_CONF_FRAG */ } else { /* * The packet does not need to be fragmented * copy "payload" and send */ memcpy(packetbuf_ptr + packetbuf_hdr_len, (uint8_t *)UIP_IP_BUF + uncomp_hdr_len, uip_len - uncomp_hdr_len); packetbuf_set_datalen(uip_len - uncomp_hdr_len + packetbuf_hdr_len); send_packet(&dest); } return 1; } /*--------------------------------------------------------------------*/ /** \brief Process a received 6lowpan packet. * * The 6lowpan packet is put in packetbuf by the MAC. If its a frag1 or * a non-fragmented packet we first uncompress the IP header. The * 6lowpan payload and possibly the uncompressed IP header are then * copied in siclowpan_buf. If the IP packet is complete it is copied * to uip_buf and the IP layer is called. * * \note We do not check for overlapping sicslowpan fragments * (it is a SHALL in the RFC 4944 and should never happen) */ static void input(void) { /* size of the IP packet (read from fragment) */ uint16_t frag_size = 0; /* offset of the fragment in the IP packet */ uint8_t frag_offset = 0; uint8_t *buffer; #if SICSLOWPAN_CONF_FRAG uint8_t is_fragment = 0; int8_t frag_context = 0; /* tag of the fragment */ uint16_t frag_tag = 0; uint8_t first_fragment = 0, last_fragment = 0; #endif /*SICSLOWPAN_CONF_FRAG*/ /* Update link statistics */ link_stats_input_callback(packetbuf_addr(PACKETBUF_ADDR_SENDER)); /* init */ uncomp_hdr_len = 0; packetbuf_hdr_len = 0; /* The MAC puts the 15.4 payload inside the packetbuf data buffer */ packetbuf_ptr = packetbuf_dataptr(); if(packetbuf_datalen() == 0) { LOG_WARN("empty packet\n"); return; } /* This is default uip_buf since we assume that this is not fragmented */ buffer = (uint8_t *)UIP_IP_BUF; /* Save the RSSI of the incoming packet in case the upper layer will want to query us for it later. */ last_rssi = (signed short)packetbuf_attr(PACKETBUF_ATTR_RSSI); #if SICSLOWPAN_CONF_FRAG /* * Since we don't support the mesh and broadcast header, the first header * we look for is the fragmentation header */ switch((GET16(PACKETBUF_FRAG_PTR, PACKETBUF_FRAG_DISPATCH_SIZE) >> 8) & SICSLOWPAN_DISPATCH_FRAG_MASK) { case SICSLOWPAN_DISPATCH_FRAG1: LOG_INFO("input: FRAG1 "); frag_offset = 0; frag_size = GET16(PACKETBUF_FRAG_PTR, PACKETBUF_FRAG_DISPATCH_SIZE) & 0x07ff; frag_tag = GET16(PACKETBUF_FRAG_PTR, PACKETBUF_FRAG_TAG); LOG_INFO("size %d, tag %d, offset %d)\n", frag_size, frag_tag, frag_offset); packetbuf_hdr_len += SICSLOWPAN_FRAG1_HDR_LEN; first_fragment = 1; is_fragment = 1; /* Add the fragment to the fragmentation context */ frag_context = add_fragment(frag_tag, frag_size, frag_offset); if(frag_context == -1) { return; } buffer = frag_info[frag_context].first_frag; break; case SICSLOWPAN_DISPATCH_FRAGN: /* * set offset, tag, size * Offset is in units of 8 bytes */ LOG_INFO("input: FRAGN "); frag_offset = PACKETBUF_FRAG_PTR[PACKETBUF_FRAG_OFFSET]; frag_tag = GET16(PACKETBUF_FRAG_PTR, PACKETBUF_FRAG_TAG); frag_size = GET16(PACKETBUF_FRAG_PTR, PACKETBUF_FRAG_DISPATCH_SIZE) & 0x07ff; LOG_INFO("size %d, tag %d, offset %d)\n", frag_size, frag_tag, frag_offset); packetbuf_hdr_len += SICSLOWPAN_FRAGN_HDR_LEN; /* If this is the last fragment, we may shave off any extrenous bytes at the end. We must be liberal in what we accept. */ LOG_INFO("last_fragment?: packetbuf_payload_len %d frag_size %d\n", packetbuf_datalen() - packetbuf_hdr_len, frag_size); /* Add the fragment to the fragmentation context (this will also copy the payload) */ frag_context = add_fragment(frag_tag, frag_size, frag_offset); if(frag_context == -1) { return; } /* Ok - add_fragment will store the fragment automatically - so we should not store more */ buffer = NULL; if(frag_info[frag_context].reassembled_len >= frag_size) { last_fragment = 1; } is_fragment = 1; break; default: break; } if(is_fragment && !first_fragment) { /* this is a FRAGN, skip the header compression dispatch section */ goto copypayload; } #endif /* SICSLOWPAN_CONF_FRAG */ /* First, process 6LoRH headers */ curr_page = 0; digest_paging_dispatch(); if(curr_page == 1) { LOG_INFO("input: page 1, 6LoRH\n"); digest_6lorh_hdr(); } else if (curr_page > 1) { LOG_ERR("input: page %u not supported\n", curr_page); return; } /* Process next dispatch and headers */ if((PACKETBUF_6LO_PTR[PACKETBUF_6LO_DISPATCH] & SICSLOWPAN_DISPATCH_IPHC_MASK) == SICSLOWPAN_DISPATCH_IPHC) { LOG_INFO("input: IPHC\n"); uncompress_hdr_iphc(buffer, frag_size); } else if(PACKETBUF_6LO_PTR[PACKETBUF_6LO_DISPATCH] == SICSLOWPAN_DISPATCH_IPV6) { LOG_INFO("input: IPV6\n"); packetbuf_hdr_len += SICSLOWPAN_IPV6_HDR_LEN; /* Put uncompressed IP header in sicslowpan_buf. */ memcpy(buffer, packetbuf_ptr + packetbuf_hdr_len, UIP_IPH_LEN); /* Update uncomp_hdr_len and packetbuf_hdr_len. */ packetbuf_hdr_len += UIP_IPH_LEN; uncomp_hdr_len += UIP_IPH_LEN; } else { LOG_ERR("input: unknown dispatch: 0x%02x\n", PACKETBUF_6LO_PTR[PACKETBUF_6LO_DISPATCH]); return; } #if SICSLOWPAN_CONF_FRAG copypayload: #endif /*SICSLOWPAN_CONF_FRAG*/ /* * copy "payload" from the packetbuf buffer to the sicslowpan_buf * if this is a first fragment or not fragmented packet, * we have already copied the compressed headers, uncomp_hdr_len * and packetbuf_hdr_len are non 0, frag_offset is. * If this is a subsequent fragment, this is the contrary. */ if(packetbuf_datalen() < packetbuf_hdr_len) { LOG_ERR("packet dropped due to header > total packet\n"); return; } packetbuf_payload_len = packetbuf_datalen() - packetbuf_hdr_len; /* Sanity-check size of incoming packet to avoid buffer overflow */ { int req_size = UIP_LLH_LEN + uncomp_hdr_len + (uint16_t)(frag_offset << 3) + packetbuf_payload_len; if(req_size > sizeof(uip_buf)) { LOG_ERR( "packet dropped, minimum required IP_BUF size: %d+%d+%d+%d=%d (current size: %u)\n", UIP_LLH_LEN, uncomp_hdr_len, (uint16_t)(frag_offset << 3), packetbuf_payload_len, req_size, (unsigned)sizeof(uip_buf)); return; } } /* copy the payload if buffer is non-null - which is only the case with first fragment or packets that are non fragmented */ if(buffer != NULL) { memcpy((uint8_t *)buffer + uncomp_hdr_len, packetbuf_ptr + packetbuf_hdr_len, packetbuf_payload_len); } /* update processed_ip_in_len if fragment, sicslowpan_len otherwise */ #if SICSLOWPAN_CONF_FRAG if(frag_size > 0) { /* Add the size of the header only for the first fragment. */ if(first_fragment != 0) { frag_info[frag_context].reassembled_len = uncomp_hdr_len + packetbuf_payload_len; frag_info[frag_context].first_frag_len = uncomp_hdr_len + packetbuf_payload_len; } /* For the last fragment, we are OK if there is extrenous bytes at the end of the packet. */ if(last_fragment != 0) { frag_info[frag_context].reassembled_len = frag_size; /* copy to uip */ copy_frags2uip(frag_context); } } /* * If we have a full IP packet in sicslowpan_buf, deliver it to * the IP stack */ if(!is_fragment || last_fragment) { /* packet is in uip already - just set length */ if(is_fragment != 0 && last_fragment != 0) { uip_len = frag_size; } else { uip_len = packetbuf_payload_len + uncomp_hdr_len; } #else uip_len = packetbuf_payload_len + uncomp_hdr_len; #endif /* SICSLOWPAN_CONF_FRAG */ LOG_INFO("input: IP packet ready (length %d)\n", uip_len); #if LOG_DBG_ENABLED { uint16_t ndx; LOG_DBG("after decompression %u:", UIP_IP_BUF->len[1]); for (ndx = 0; ndx < UIP_IP_BUF->len[1] + 40; ndx++) { uint8_t data = ((uint8_t *) (UIP_IP_BUF))[ndx]; LOG_DBG("%02x", data); } LOG_DBG("\n"); } #endif /* LOG_DBG_ENABLED */ /* if callback is set then set attributes and call */ if(callback) { set_packet_attrs(); callback->input_callback(); } tcpip_input(); #if SICSLOWPAN_CONF_FRAG } #endif /* SICSLOWPAN_CONF_FRAG */ } /** @} */ /*--------------------------------------------------------------------*/ /* \brief 6lowpan init function (called by the MAC layer) */ /*--------------------------------------------------------------------*/ void sicslowpan_init(void) { /* * Set out output function as the function to be called from uIP to * send a packet. */ tcpip_set_outputfunc(output); #if SICSLOWPAN_COMPRESSION == SICSLOWPAN_COMPRESSION_IPHC /* Preinitialize any address contexts for better header compression * (Saves up to 13 bytes per 6lowpan packet) * The platform contiki-conf.h file can override this using e.g. * #define SICSLOWPAN_CONF_ADDR_CONTEXT_0 {addr_contexts[0].prefix[0]=0xbb;addr_contexts[0].prefix[1]=0xbb;} */ #if SICSLOWPAN_CONF_MAX_ADDR_CONTEXTS > 0 addr_contexts[0].used = 1; addr_contexts[0].number = 0; #ifdef SICSLOWPAN_CONF_ADDR_CONTEXT_0 SICSLOWPAN_CONF_ADDR_CONTEXT_0; #else addr_contexts[0].prefix[0] = UIP_DS6_DEFAULT_PREFIX_0; addr_contexts[0].prefix[1] = UIP_DS6_DEFAULT_PREFIX_1; #endif #endif /* SICSLOWPAN_CONF_MAX_ADDR_CONTEXTS > 0 */ #if SICSLOWPAN_CONF_MAX_ADDR_CONTEXTS > 1 { int i; for(i = 1; i < SICSLOWPAN_CONF_MAX_ADDR_CONTEXTS; i++) { #ifdef SICSLOWPAN_CONF_ADDR_CONTEXT_1 if (i==1) { addr_contexts[1].used = 1; addr_contexts[1].number = 1; SICSLOWPAN_CONF_ADDR_CONTEXT_1; #ifdef SICSLOWPAN_CONF_ADDR_CONTEXT_2 } else if (i==2) { addr_contexts[2].used = 1; addr_contexts[2].number = 2; SICSLOWPAN_CONF_ADDR_CONTEXT_2; #endif } else { addr_contexts[i].used = 0; } #else addr_contexts[i].used = 0; #endif /* SICSLOWPAN_CONF_ADDR_CONTEXT_1 */ } } #endif /* SICSLOWPAN_CONF_MAX_ADDR_CONTEXTS > 1 */ #endif /* SICSLOWPAN_COMPRESSION == SICSLOWPAN_COMPRESSION_IPHC */ } /*--------------------------------------------------------------------*/ int sicslowpan_get_last_rssi(void) { return last_rssi; } /*--------------------------------------------------------------------*/ const struct network_driver sicslowpan_driver = { "sicslowpan", sicslowpan_init, input }; /*--------------------------------------------------------------------*/ /** @} */