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From Owen Kirby: 

6LoWPAN: Automatic context detection and draft-ietf-6lowpan-nd-19 updates.

https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=7521

svn path=/trunk/; revision=44723
This commit is contained in:
Anders Broman 2012-09-01 11:54:16 +00:00
parent 4b6ad1d9d7
commit e128334750
5 changed files with 359 additions and 89 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

394
epan/dissectors/packet-6lowpan.c
View File

@ -56,6 +56,7 @@
#include <epan/in_cksum.h>
#include "packet-ipv6.h"
#include "packet-ieee802154.h"
#include "packet-6lowpan.h"
/* Definitions for 6lowpan packet disassembly structures and routines */
@ -239,6 +240,11 @@ static int hf_6lowpan_iphc_flag_dam = -1;
static int hf_6lowpan_iphc_sci = -1;
static int hf_6lowpan_iphc_dci = -1;
static int hf_6lowpan_iphc_sctx_prefix = -1;
static int hf_6lowpan_iphc_sctx_origin = -1;
static int hf_6lowpan_iphc_dctx_prefix = -1;
static int hf_6lowpan_iphc_dctx_origin = -1;
/* NHC IPv6 extension header fields. */
static int hf_6lowpan_nhc_ext_eid = -1;
static int hf_6lowpan_nhc_ext_nh = -1;
@ -407,18 +413,34 @@ static const fragment_items lowpan_frag_items = {
static GHashTable *lowpan_fragment_table = NULL;
static GHashTable *lowpan_reassembled_table = NULL;
static GHashTable *lowpan_context_table = NULL;
/* Link-Local prefix used by 6LoWPAN (FF80::) */
/* Link-Local prefix used by 6LoWPAN (FF80::/10) */
static const guint8 lowpan_llprefix[8] = {
0xfe, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};
/* 6LoWPAN context table preferences. */
#define LOWPAN_CONTEXT_COUNT 16
#define LOWPAN_CONTEXT_DEFAULT 0
#define LOWPAN_CONTEXT_LINK_LOCAL LOWPAN_CONTEXT_COUNT /* An internal context used for the link-local prefix. */
static struct e_in6_addr lowpan_context_table[LOWPAN_CONTEXT_COUNT+1]; /* The 17-th context stores the link-local prefix. */
static const gchar * lowpan_context_prefs[LOWPAN_CONTEXT_COUNT]; /* Array of strings set by the preferences. */
/* Context hash table map key. */
typedef struct {
guint16 pan; /* PAN Identifier */
guint8 cid; /* Context Identifier */
} lowpan_context_key;
/* Context hash table map data. */
typedef struct {
guint frame; /* Frame where the context was discovered. */
guint8 plen; /* Prefix length. */
struct e_in6_addr prefix; /* Compression context. */
} lowpan_context_data;
/* 6LoWPAN contexts. */
#define LOWPAN_CONTEXT_MAX 16
#define LOWPAN_CONTEXT_DEFAULT 0
#define LOWPAN_CONTEXT_LINK_LOCAL LOWPAN_CONTEXT_MAX
#define LOWPAN_CONTEXT_LINK_LOCAL_BITS 10
static lowpan_context_data lowpan_context_local;
static lowpan_context_data lowpan_context_default;
static const gchar * lowpan_context_prefs[LOWPAN_CONTEXT_MAX];
/* Helper macro to convert a bit offset/length into a byte count. */
#define BITS_TO_BYTE_LEN(bitoff, bitlen) ((bitlen)?(((bitlen) + ((bitoff)&0x07) + 7) >> 3):(0))
@ -465,6 +487,163 @@ static void lowpan_addr16_to_ifcid (guint16 addr, guint8 *ifcid);
static tvbuff_t * lowpan_reassemble_ipv6 (tvbuff_t *tvb, struct ip6_hdr * ipv6, struct lowpan_nhdr * nhdr_list);
static guint8 lowpan_parse_nhc_proto (tvbuff_t *tvb, gint offset);
/* Context table helpers */
static guint lowpan_context_hash (gconstpointer key);
static gboolean lowpan_context_equal (gconstpointer a, gconstpointer b);
static lowpan_context_data *lowpan_context_find(guint8 cid, guint16 pan);
/*FUNCTION:------------------------------------------------------
* NAME
* lowpan_pfxcpy
* DESCRIPTION
* A version of memcpy that takes a length in bits. If the
* length is not byte-aligned, the final byte will be
* manipulated so that only the desired number of bits are
* copied.
* PARAMETERS
* dst ; Destination.
* src ; Source.
* bits ; Number of bits to copy.
* RETURNS
* void ;
*---------------------------------------------------------------
*/
static void
lowpan_pfxcpy(void *dst, const void *src, size_t bits)
{
memcpy(dst, src, bits>>3);
if (bits & 0x7) {
guint8 mask = ((0xff00) >> (bits & 0x7));
guint8 last = ((guint8 *)src)[bits>>3] & mask;
((guint8 *)dst)[bits>>3] &= ~mask;
((guint8 *)dst)[bits>>3] |= last;
}
} /* lowpan_pfxcpy */
/*FUNCTION:------------------------------------------------------
* NAME
* lowpan_context_hash
* DESCRIPTION
* Context table hash function.
* PARAMETERS
* key ; Pointer to a lowpan_context_key type.
* RETURNS
* guint ; The hashed key value.
*---------------------------------------------------------------
*/
static guint
lowpan_context_hash(gconstpointer key)
{
return (((lowpan_context_key *)key)->cid) | (((lowpan_context_key *)key)->pan << 8);
} /* lowpan_context_hash */
/*FUNCTION:------------------------------------------------------
* NAME
* lowpan_context_equal
* DESCRIPTION
* Context table equals function.
* PARAMETERS
* key ; Pointer to a lowpan_context_key type.
* RETURNS
* gboolean ;
*---------------------------------------------------------------
*/
static gboolean
lowpan_context_equal(gconstpointer a, gconstpointer b)
{
return (((lowpan_context_key *)a)->pan == ((lowpan_context_key *)b)->pan) &&
(((lowpan_context_key *)a)->cid == ((lowpan_context_key *)b)->cid);
} /* lowpan_context_equal */
/*FUNCTION:------------------------------------------------------
* NAME
* lowpan_context_find
* DESCRIPTION
* Context table lookup function.
* PARAMETERS
* cid ; Context identifier.
* pan ; PAN identifier.
* RETURNS
* lowpan_context_data *;
*---------------------------------------------------------------
*/
static lowpan_context_data *
lowpan_context_find(guint8 cid, guint16 pan)
{
lowpan_context_key key;
lowpan_context_data *data;
/* Check for the internal link-local context. */
if (cid == LOWPAN_CONTEXT_LINK_LOCAL) return &lowpan_context_local;
/* Lookup the context from the table. */
key.pan = pan;
key.cid = cid;
data = g_hash_table_lookup(lowpan_context_table, &key);
if (data) return data;
/* If we didn't find a match, try again with the broadcast PAN. */
if (pan != IEEE802154_BCAST_PAN) {
key.pan = IEEE802154_BCAST_PAN;
data = g_hash_table_lookup(lowpan_context_table, &key);
if (data) return data;
}
/* If the lookup failed, return the default context (::/0) */
return &lowpan_context_default;
} /* lowpan_context_find */
/*FUNCTION:------------------------------------------------------
* NAME
* lowpan_context_insert
* DESCRIPTION
* Context table insert function.
* PARAMETERS
* cid ; Context identifier.
* pan ; PAN identifier.
* plen ; Prefix length.
* prefix ; Compression prefix.
* frame ; Frame number.
* RETURNS
* void ;
*---------------------------------------------------------------
*/
void
lowpan_context_insert(guint8 cid, guint16 pan, guint8 plen, struct e_in6_addr *prefix, guint frame)
{
lowpan_context_key key;
lowpan_context_data *data;
gpointer pkey;
gpointer pdata;
/* Sanity! */
if (plen > 128) return;
if (!prefix) return;
/* Search the context table for an existing entry. */
key.pan = pan;
key.cid = cid;
if (g_hash_table_lookup_extended(lowpan_context_table, &key, &pkey, &pdata)) {
/* Context already exists. */
data = pdata;
if ( (data->plen == plen) && (memcmp(&data->prefix, prefix, (plen+7)/8) == 0) ) {
/* Context already exists with no change. */
return;
}
}
else {
pkey = se_memdup(&key, sizeof(key));
}
/* Create a new context */
data = se_alloc(sizeof(lowpan_context_data));
data->frame = frame;
data->plen = plen;
memset(&data->prefix, 0, sizeof(struct e_in6_addr)); /* Ensure zero paddeding */
lowpan_pfxcpy(&data->prefix, prefix, plen);
g_hash_table_insert(lowpan_context_table, pkey, data);
} /* lowpan_context_insert */
/*FUNCTION:------------------------------------------------------
* NAME
* lowpan_addr16_to_ifcid
@ -509,8 +688,8 @@ lowpan_addr16_to_ifcid(guint16 addr, guint8 *ifcid)
static gboolean
lowpan_dlsrc_to_ifcid(packet_info *pinfo, guint8 *ifcid)
{
ieee802154_packet * packet = (ieee802154_packet *)pinfo->private_data;
ieee802154_hints_t *hints;
/* Check the link-layer address field. */
if (pinfo->dl_src.type == AT_EUI64) {
memcpy(ifcid, pinfo->dl_src.data, LOWPAN_IFC_ID_LEN);
@ -518,23 +697,17 @@ lowpan_dlsrc_to_ifcid(packet_info *pinfo, guint8 *ifcid)
ifcid[0] ^= 0x02;
return TRUE;
}
/* Derive the IID from the IEEE 802.15.4 packet structure. */
if (packet->src_addr_mode == IEEE802154_FCF_ADDR_EXT) {
guint64 addr;
addr = pntoh64(&packet->src64);
memcpy(ifcid, &addr, LOWPAN_IFC_ID_LEN);
/* RFC2464: Invert the U/L bit when using an EUI64 address. */
ifcid[0] ^= 0x02;
/* Lookup the IEEE 802.15.4 addressing hints. */
hints = (ieee802154_hints_t *)p_get_proto_data(pinfo->fd,
proto_get_id_by_filter_name(IEEE802154_PROTOABBREV_WPAN));
if (hints) {
lowpan_addr16_to_ifcid(hints->src16, ifcid);
return TRUE;
} else {
/* Failed to find a link-layer source address. */
return FALSE;
}
if (packet->src_addr_mode == IEEE802154_FCF_ADDR_SHORT) {
lowpan_addr16_to_ifcid(packet->src16, ifcid);
return TRUE;
}
/* Failed to find a link-layer source address. */
return FALSE;
} /* lowpan_dlsrc_to_ifcid */
/*FUNCTION:------------------------------------------------------
@ -554,7 +727,7 @@ lowpan_dlsrc_to_ifcid(packet_info *pinfo, guint8 *ifcid)
static gboolean
lowpan_dldst_to_ifcid(packet_info *pinfo, guint8 *ifcid)
{
ieee802154_packet * packet = (ieee802154_packet *)pinfo->private_data;
ieee802154_hints_t *hints;
/* Check the link-layer address field. */
if (pinfo->dl_dst.type == AT_EUI64) {
@ -563,23 +736,17 @@ lowpan_dldst_to_ifcid(packet_info *pinfo, guint8 *ifcid)
ifcid[0] ^= 0x02;
return TRUE;
}
/* Derive the IID from the IEEE 802.15.4 packet structure. */
if (packet->dst_addr_mode == IEEE802154_FCF_ADDR_EXT) {
guint64 addr;
addr = pntoh64(&packet->dst64);
memcpy(ifcid, &addr, LOWPAN_IFC_ID_LEN);
/* RFC2464: Invert the U/L bit when using an EUI64 address. */
ifcid[0] ^= 0x02;
/* Lookup the IEEE 802.15.4 addressing hints. */
hints = (ieee802154_hints_t *)p_get_proto_data(pinfo->fd,
proto_get_id_by_filter_name(IEEE802154_PROTOABBREV_WPAN));
if (hints) {
lowpan_addr16_to_ifcid(hints->dst16, ifcid);
return TRUE;
} else {
/* Failed to find a link-layer destination address. */
return FALSE;
}
if (packet->dst_addr_mode == IEEE802154_FCF_ADDR_SHORT) {
lowpan_addr16_to_ifcid(packet->dst16, ifcid);
return TRUE;
}
/* Failed to find a link-layer source address. */
return FALSE;
} /* lowpan_dldst_to_ifcid */
/*FUNCTION:------------------------------------------------------
@ -1177,6 +1344,8 @@ dissect_6lowpan_hc1(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gint dg
static tvbuff_t *
dissect_6lowpan_iphc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gint dgram_size, guint8 *siid, guint8 *diid)
{
ieee802154_hints_t *hints;
guint16 hint_panid;
gint offset = 0;
gint length = 0;
proto_tree * iphc_tree = NULL;
@ -1189,15 +1358,22 @@ dissect_6lowpan_iphc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gint d
guint8 iphc_src_mode;
guint8 iphc_dst_mode;
guint8 iphc_ctx = 0;
/* Default contexts to use for address decompression. */
/* Contexts to use for address decompression. */
gint iphc_sci = LOWPAN_CONTEXT_DEFAULT;
gint iphc_dci = LOWPAN_CONTEXT_DEFAULT;
lowpan_context_data *sctx;
lowpan_context_data *dctx;
/* IPv6 header */
guint8 ipv6_class = 0;
struct ip6_hdr ipv6;
tvbuff_t * ipv6_tvb;
/* Next header chain */
struct lowpan_nhdr *nhdr_list;
struct lowpan_nhdr *nhdr_list;
/* Lookup the IEEE 802.15.4 addressing hints. */
hints = (ieee802154_hints_t *)p_get_proto_data(pinfo->fd,
proto_get_id_by_filter_name(IEEE802154_PROTOABBREV_WPAN));
hint_panid = (hints) ? (hints->src_pan) : (IEEE802154_BCAST_PAN);
/* Create a tree for the IPHC header. */
if (tree) {
@ -1252,6 +1428,13 @@ dissect_6lowpan_iphc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gint d
if (!(iphc_flags & LOWPAN_IPHC_FLAG_DST_COMP)) {
iphc_dci = LOWPAN_CONTEXT_LINK_LOCAL;
}
/* Lookup the contexts. */
/*
* Don't display their origin until after we decompress the address in case
* the address modes indicate that we should use a different context.
*/
sctx = lowpan_context_find(iphc_sci, hint_panid);
dctx = lowpan_context_find(iphc_dci, hint_panid);
/*=====================================================
* Parse Traffic Class and Flow Label
@ -1335,25 +1518,26 @@ dissect_6lowpan_iphc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gint d
* Parse and decompress the source address.
*=====================================================
*/
/* Copy the address from the context table. */
memcpy(&ipv6.ip6_src, &lowpan_context_table[iphc_sci], sizeof(ipv6.ip6_src));
length = 0;
memset(&ipv6.ip6_src, 0, sizeof(ipv6.ip6_src));
/* (SAC=1 && SAM=00) -> the unspecified address (::). */
if ((iphc_flags & LOWPAN_IPHC_FLAG_SRC_COMP) && (iphc_src_mode == LOWPAN_IPHC_ADDR_SRC_UNSPEC)) {
length = 0;
memset(&ipv6.ip6_src, 0, sizeof(ipv6.ip6_src));
sctx = &lowpan_context_default;
}
/* The IID is derived from the encapsulating layer. */
else if (iphc_src_mode == LOWPAN_IPHC_ADDR_COMPRESSED) {
length = 0;
memcpy(&ipv6.ip6_src.bytes[sizeof(ipv6.ip6_src) - LOWPAN_IFC_ID_LEN], siid, LOWPAN_IFC_ID_LEN);
}
/* Full Address inline. */
else if (iphc_src_mode == LOWPAN_IPHC_ADDR_FULL_INLINE) {
if (!(iphc_flags & LOWPAN_IPHC_FLAG_SRC_COMP)) sctx = &lowpan_context_default;
length = sizeof(ipv6.ip6_src);
tvb_memcpy(tvb, &ipv6.ip6_src, offset, length);
}
/* 64-bits inline. */
else if (iphc_src_mode == LOWPAN_IPHC_ADDR_64BIT_INLINE) {
length = sizeof(guint64);
tvb_memcpy(tvb, &ipv6.ip6_src.bytes[sizeof(ipv6.ip6_src) - length], offset, length);
}
/* 16-bits inline. */
else if (iphc_src_mode == LOWPAN_IPHC_ADDR_16BIT_INLINE) {
@ -1361,11 +1545,11 @@ dissect_6lowpan_iphc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gint d
/* Format becomes ff:fe00:xxxx */
ipv6.ip6_src.bytes[11] = 0xff;
ipv6.ip6_src.bytes[12] = 0xfe;
tvb_memcpy(tvb, &ipv6.ip6_src.bytes[sizeof(ipv6.ip6_src) - length], offset, length);
}
if (length) {
tvb_memcpy(tvb, &ipv6.ip6_src.bytes[sizeof(ipv6.ip6_src) - length], offset, length);
}
/* Copy the context bits. */
lowpan_pfxcpy(&ipv6.ip6_src, &sctx->prefix, sctx->plen);
/* Update the IID of the encapsulating layer. */
siid = &ipv6.ip6_src.bytes[sizeof(ipv6.ip6_src) - LOWPAN_IFC_ID_LEN];
@ -1373,6 +1557,16 @@ dissect_6lowpan_iphc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gint d
if (tree) {
proto_tree_add_ipv6(tree, hf_6lowpan_source, tvb, offset, length, (guint8 *)&ipv6.ip6_src);
}
/* Add information about where the context came from. */
/* TODO: We should display the prefix length too. */
if (tree && sctx->plen) {
ti = proto_tree_add_ipv6(iphc_tree, hf_6lowpan_iphc_sctx_prefix, tvb, 0, 0, (guint8 *)&sctx->prefix);
PROTO_ITEM_SET_GENERATED(ti);
if ( sctx->frame ) {
ti = proto_tree_add_uint(iphc_tree, hf_6lowpan_iphc_sctx_origin, tvb, 0, 0, sctx->frame);
PROTO_ITEM_SET_GENERATED(ti);
}
}
offset += length;
/*
* Do not set the address columns until after defragmentation, since we have
@ -1384,10 +1578,10 @@ dissect_6lowpan_iphc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gint d
* Parse and decompress a multicast address.
*=====================================================
*/
length = 0;
memset(&ipv6.ip6_dst, 0, sizeof(ipv6.ip6_dst));
/* Stateless multicast compression. */
if ((iphc_flags & LOWPAN_IPHC_FLAG_MCAST_COMP) && !(iphc_flags & LOWPAN_IPHC_FLAG_DST_COMP)) {
length = 0;
memset(&ipv6.ip6_dst, 0, sizeof(ipv6.ip6_dst));
if (iphc_dst_mode == LOWPAN_IPHC_ADDR_FULL_INLINE) {
length = sizeof(ipv6.ip6_dst);
tvb_memcpy(tvb, &ipv6.ip6_dst.bytes[sizeof(ipv6.ip6_dst) - length], offset, length);
@ -1421,14 +1615,18 @@ dissect_6lowpan_iphc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gint d
}
/* Stateful multicast compression. */
else if ((iphc_flags & LOWPAN_IPHC_FLAG_MCAST_COMP) && (iphc_flags & LOWPAN_IPHC_FLAG_DST_COMP)) {
length = 0;
memset(&ipv6.ip6_dst, 0, sizeof(ipv6.ip6_dst));
if (iphc_dst_mode == LOWPAN_IPHC_MCAST_STATEFUL_48BIT) {
/* RFC 3306 unicast-prefix based multicast address. */
/* RFC 3306 unicast-prefix based multicast address of the form:
* ffXX:XXLL:PPPP:PPPP:PPPP:PPPP:XXXX:XXXX
* XX = inline byte.
* LL = prefix/context length (up to 64-bits).
* PP = prefix/context byte.
*/
ipv6.ip6_dst.bytes[0] = 0xff;
ipv6.ip6_dst.bytes[1] = tvb_get_guint8(tvb, offset + (length++));
ipv6.ip6_dst.bytes[2] = tvb_get_guint8(tvb, offset + (length++));
/* TODO: Recover the stuff derived from context. */
ipv6.ip6_dst.bytes[3] = (dctx->plen > 64) ? (64) : (dctx->plen);
memcpy(&ipv6.ip6_dst.bytes[4], &dctx->prefix, 8);
ipv6.ip6_dst.bytes[12] = tvb_get_guint8(tvb, offset + (length++));
ipv6.ip6_dst.bytes[13] = tvb_get_guint8(tvb, offset + (length++));
ipv6.ip6_dst.bytes[14] = tvb_get_guint8(tvb, offset + (length++));
@ -1446,27 +1644,26 @@ dissect_6lowpan_iphc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gint d
*=====================================================
*/
else {
/* Copy the address from the context table. */
length = 0;
memcpy(&ipv6.ip6_dst, &lowpan_context_table[iphc_dci], sizeof(ipv6.ip6_dst));
/* (DAC=1 && DAM=00) -> reserved value. */
if ((iphc_flags & LOWPAN_IPHC_FLAG_DST_COMP) && (iphc_dst_mode == 0)) {
if ((iphc_flags & LOWPAN_IPHC_FLAG_DST_COMP) && (iphc_dst_mode == LOWPAN_IPHC_ADDR_FULL_INLINE)) {
/* Illegal destination address compression mode. */
expert_add_info_format(pinfo, ti_dam, PI_MALFORMED, PI_ERROR, "Illegal destination address mode");
return NULL;
}
/* The IID is derived from the link-layer source. */
else if (iphc_dst_mode == LOWPAN_IPHC_ADDR_COMPRESSED) {
length = 0;
memcpy(&ipv6.ip6_dst.bytes[sizeof(ipv6.ip6_dst) - LOWPAN_IFC_ID_LEN], diid, LOWPAN_IFC_ID_LEN);
}
/* Full Address inline. */
else if (iphc_dst_mode == LOWPAN_IPHC_ADDR_FULL_INLINE) {
dctx = &lowpan_context_default;
length = sizeof(ipv6.ip6_dst);
tvb_memcpy(tvb, &ipv6.ip6_dst, offset, length);
}
/* 64-bits inline. */
else if (iphc_dst_mode == LOWPAN_IPHC_ADDR_64BIT_INLINE) {
length = sizeof(guint64);
tvb_memcpy(tvb, &ipv6.ip6_dst.bytes[sizeof(ipv6.ip6_dst) - length], offset, length);
}
/* 16-bits inline. */
else if (iphc_dst_mode == LOWPAN_IPHC_ADDR_16BIT_INLINE) {
@ -1474,10 +1671,10 @@ dissect_6lowpan_iphc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gint d
/* Format becomes ff:fe00:xxxx */
ipv6.ip6_dst.bytes[11] = 0xff;
ipv6.ip6_dst.bytes[12] = 0xfe;
}
if (length) {
tvb_memcpy(tvb, &ipv6.ip6_dst.bytes[sizeof(ipv6.ip6_dst) - length], offset, length);
}
/* Copy the context bits. */
lowpan_pfxcpy(&ipv6.ip6_dst, &dctx->prefix, dctx->plen);
/* Update the interface id of the encapsulating layer. */
diid = &ipv6.ip6_dst.bytes[sizeof(ipv6.ip6_dst) - LOWPAN_IFC_ID_LEN];
}
@ -1486,6 +1683,16 @@ dissect_6lowpan_iphc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gint d
if (tree) {
proto_tree_add_ipv6(tree, hf_6lowpan_dest, tvb, offset, length, (guint8 *)&ipv6.ip6_dst);
}
/* Add information about where the context came from. */
/* TODO: We should display the prefix length too. */
if (tree && dctx->plen) {
ti = proto_tree_add_ipv6(iphc_tree, hf_6lowpan_iphc_dctx_prefix, tvb, 0, 0, (guint8 *)&dctx->prefix);
PROTO_ITEM_SET_GENERATED(ti);
if ( dctx->frame ) {
ti = proto_tree_add_uint(iphc_tree, hf_6lowpan_iphc_dctx_origin, tvb, 0, 0, dctx->frame);
PROTO_ITEM_SET_GENERATED(ti);
}
}
offset += length;
/*
* Do not set the address columns until after defragmentation, since we have
@ -2357,6 +2564,20 @@ proto_register_6lowpan(void)
{ "Destination context identifier", "6lowpan.iphc.dci",
FT_UINT8, BASE_HEX, NULL, LOWPAN_IPHC_FLAG_DCI, NULL, HFILL }},
/* Context information fields. */
{ &hf_6lowpan_iphc_sctx_prefix,
{ "Source context", "6lowpan.iphc.sctx.prefix", FT_IPv6, BASE_NONE, NULL, 0x0,
NULL, HFILL }},
{ &hf_6lowpan_iphc_sctx_origin,
{ "Origin", "6lowpan.iphc.sctx.origin", FT_FRAMENUM, BASE_NONE, NULL, 0x0,
NULL, HFILL }},
{ &hf_6lowpan_iphc_dctx_prefix,
{ "Destination context", "6lowpan.iphc.dctx.prefix", FT_IPv6, BASE_NONE, NULL, 0x0,
NULL, HFILL }},
{ &hf_6lowpan_iphc_dctx_origin,
{ "Origin", "6lowpan.iphc.dctx.origin", FT_FRAMENUM, BASE_NONE, NULL, 0x0,
NULL, HFILL }},
/* NHC IPv6 extension header fields. */
{ &hf_6lowpan_nhc_ext_eid,
{ "Header ID", "6lowpan.nhc.ext.eid",
@ -2516,7 +2737,6 @@ proto_register_6lowpan(void)
int i;
module_t *prefs_module;
static gchar init_context_str[] = "2002:db8::ff:fe00:0";
proto_6lowpan = proto_register_protocol("IPv6 over IEEE 802.15.4", "6LoWPAN", "6lowpan");
proto_register_field_array(proto_6lowpan, hf, array_length(hf));
@ -2528,26 +2748,12 @@ proto_register_6lowpan(void)
/* Register the dissector init function */
register_init_routine(proto_init_6lowpan);
/* Initialize the context table. */
memset(lowpan_context_table, 0, sizeof(lowpan_context_table));
/* Initialize the context preferences. */
memset((gchar*)lowpan_context_prefs, 0, sizeof(lowpan_context_prefs));
/* Initialize the link-local prefix. */
lowpan_context_table[LOWPAN_CONTEXT_LINK_LOCAL].bytes[0] = 0xfe;
lowpan_context_table[LOWPAN_CONTEXT_LINK_LOCAL].bytes[1] = 0x80;
/* Initialize the default values of the context table. */
lowpan_context_prefs[LOWPAN_CONTEXT_DEFAULT] = init_context_str;
lowpan_context_table[LOWPAN_CONTEXT_DEFAULT].bytes[0] = 0x20;
lowpan_context_table[LOWPAN_CONTEXT_DEFAULT].bytes[1] = 0x02;
lowpan_context_table[LOWPAN_CONTEXT_DEFAULT].bytes[2] = 0x0d;
lowpan_context_table[LOWPAN_CONTEXT_DEFAULT].bytes[3] = 0xb8;
lowpan_context_table[LOWPAN_CONTEXT_DEFAULT].bytes[11] = 0xff;
lowpan_context_table[LOWPAN_CONTEXT_DEFAULT].bytes[12] = 0xfe;
/* Register preferences. */
prefs_module = prefs_register_protocol(proto_6lowpan, prefs_6lowpan_apply);
for (i = 0; i < LOWPAN_CONTEXT_COUNT; i++) {
for (i = 0; i < LOWPAN_CONTEXT_MAX; i++) {
char *pref_name, *pref_title;
/*
@ -2579,8 +2785,23 @@ proto_register_6lowpan(void)
static void
proto_init_6lowpan(void)
{
/* Initialize the fragment reassembly table. */
fragment_table_init(&lowpan_fragment_table);
reassembled_table_init(&lowpan_reassembled_table);
/* Initialize the context table. */
if (lowpan_context_table)
g_hash_table_destroy(lowpan_context_table);
lowpan_context_table = g_hash_table_new(lowpan_context_hash, lowpan_context_equal);
/* Initialize the link-local context. */
lowpan_context_local.frame = 0;
lowpan_context_local.plen = LOWPAN_CONTEXT_LINK_LOCAL_BITS;
memcpy(&lowpan_context_local.prefix, lowpan_llprefix, sizeof(lowpan_llprefix));
/* Reload static contexts from our preferences. */
prefs_6lowpan_apply();
} /* proto_init_6lowpan */
/*FUNCTION:------------------------------------------------------
@ -2598,13 +2819,14 @@ proto_init_6lowpan(void)
void
prefs_6lowpan_apply(void)
{
int i;
int i;
struct e_in6_addr prefix;
for (i = 0; i < LOWPAN_CONTEXT_COUNT; i++) {
if (!(lowpan_context_prefs[i]) || (inet_pton(AF_INET6, lowpan_context_prefs[i], &lowpan_context_table[i]) != 1)) {
/* Missing, or invalid IPv6 address, clear the context. */
memset(&lowpan_context_table[i], 0, sizeof(struct e_in6_addr));
}
for (i = 0; i < LOWPAN_CONTEXT_MAX; i++) {
if (!lowpan_context_prefs[i]) continue;
if (inet_pton(AF_INET6, lowpan_context_prefs[i], &prefix) != 1) continue;
/* Set the prefix */
lowpan_context_insert(i, IEEE802154_BCAST_PAN, 64, &prefix, 0);
} /* for */
} /* prefs_6lowpan_apply */

31
epan/dissectors/packet-6lowpan.h Normal file
View File

@ -0,0 +1,31 @@
/* packet-6lowpan.h
* Routines for 6LoWPAN packet disassembly
*
* $Id$
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#ifndef __PACKET_6LOWPAN_H__
#define __PACKET_6LOWPAN_H__
/* Inserts new compression context information into the 6LoWPAN context table.
* The compression context is distributed via some options added to the neighbor
* discovery protocol, so the ICMPv6 dissector needs to call this routine.
*/
extern void lowpan_context_insert(guint8 cid, guint16 pan, guint8 plen,
struct e_in6_addr *prefix, guint frame);
#endif /* __PACKET_6LOWPAN_H__ */

18
epan/dissectors/packet-icmpv6.c
View File

@ -57,6 +57,8 @@
#include "packet-x509af.h"
#include "packet-x509if.h"
#include "packet-icmp.h" /* same transaction_t used both both v4 and v6 */
#include "packet-ieee802154.h"
#include "packet-6lowpan.h"
/*
* The information used comes from:
@ -2056,16 +2058,19 @@ dissect_icmpv6_nd_opt(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree
break;
case ND_OPT_6LOWPAN_CONTEXT: /* 6LoWPAN Context (TBD2 Pending IANA...) */
{
ieee802154_hints_t *hints;
/* 6lowpan-ND */
guint8 context_id;
guint8 context_len;
struct e_in6_addr context_prefix;
/* Context Length */
proto_tree_add_item(icmp6opt_tree, hf_icmpv6_opt_6co_context_length, tvb, opt_offset, 1, ENC_BIG_ENDIAN);
context_len = tvb_get_guint8(tvb, opt_offset);
opt_offset += 1;
/* Flags & CID */
context_id = tvb_get_guint8(tvb, opt_offset) & ND_OPT_6CO_FLAG_CID;
ti_opt = proto_tree_add_item(icmp6opt_tree, hf_icmpv6_opt_6co_flag, tvb, opt_offset, 1, ENC_BIG_ENDIAN);
flag_tree = proto_item_add_subtree(ti_opt, ett_icmpv6_flag_6lowpan);
proto_tree_add_item(flag_tree, hf_icmpv6_opt_6co_flag_c, tvb, opt_offset, 1, ENC_BIG_ENDIAN);
@ -2080,20 +2085,21 @@ dissect_icmpv6_nd_opt(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree
/* Lifetime */
proto_tree_add_item(icmp6opt_tree, hf_icmpv6_opt_6co_valid_lifetime, tvb, opt_offset, 2, ENC_BIG_ENDIAN);
opt_offset += 2;
/* Context */
memset(&context_prefix.bytes, 0, sizeof(context_prefix));
switch(opt_len){
case 8: /* Default Option Length without context prefix */
proto_item_append_text(ti, " ::/%d", context_len);
break;
case 16:
memset(&context_prefix, 0, sizeof(context_prefix));
tvb_memcpy(tvb, (guint8 *)&context_prefix.bytes, opt_offset, 8);
proto_tree_add_ipv6(icmp6opt_tree, hf_icmpv6_opt_6co_context_prefix, tvb, opt_offset, 8, context_prefix.bytes);
proto_item_append_text(ti, " %s/%d", ip6_to_str(&context_prefix), context_len);
opt_offset += 8;
break;
case 24:
tvb_memcpy(tvb, (guint8 *)&context_prefix.bytes, opt_offset, 16);
proto_tree_add_item(icmp6opt_tree, hf_icmpv6_opt_6co_context_prefix, tvb, opt_offset, 16, ENC_NA);
proto_item_append_text(ti, " %s/%d", tvb_ip6_to_str(tvb, opt_offset), context_len);
opt_offset += 16;
@ -2102,6 +2108,12 @@ dissect_icmpv6_nd_opt(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree
expert_add_info_format(pinfo, ti_opt_len, PI_MALFORMED, PI_ERROR, "Invalid Option Length");
break;
}
/* Update the 6LoWPAN dissectors with new context information. */
hints = (ieee802154_hints_t *)p_get_proto_data(pinfo->fd,
proto_get_id_by_filter_name(IEEE802154_PROTOABBREV_WPAN));
if ((opt_len <= 24) && hints) {
lowpan_context_insert(context_id, hints->src_pan, context_len, &context_prefix, pinfo->fd->num);
}
}
break;
case ND_OPT_AUTH_BORDER_ROUTER: /* Authoritative Border Router (33) */

4
epan/dissectors/packet-ieee802154.c
View File

@ -712,6 +712,10 @@ dissect_ieee802154_common(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, g
else {
g_snprintf(dst_addr, 32, "0x%04x", packet->dst16);
}
/* Provide address hints to higher layers that need it. */
if (ieee_hints) {
ieee_hints->dst16 = packet->dst16;
}
SET_ADDRESS(&pinfo->dl_dst, AT_STRINGZ, (int)strlen(dst_addr)+1, dst_addr);
SET_ADDRESS(&pinfo->dst, AT_STRINGZ, (int)strlen(dst_addr)+1, dst_addr);

1
epan/dissectors/packet-ieee802154.h
View File

@ -237,6 +237,7 @@ typedef struct {
typedef struct {
guint16 src_pan;
guint16 src16;
guint16 dst16;
ieee802154_map_rec *map_rec;
} ieee802154_hints_t;