diff options
| -rw-r--r-- | epan/dissectors/packet-mac-lte.c | 141 | ||||
| -rw-r--r-- | epan/dissectors/packet-mac-lte.h | 59 | ||||
| -rw-r--r-- | gtk/mac_lte_stat_dlg.c | 8 |
3 files changed, 203 insertions, 5 deletions
diff --git a/epan/dissectors/packet-mac-lte.c b/epan/dissectors/packet-mac-lte.c index aaa7d4adf4..0d64e581ad 100644 --- a/epan/dissectors/packet-mac-lte.c +++ b/epan/dissectors/packet-mac-lte.c @@ -368,6 +368,124 @@ static gboolean global_mac_lte_attempt_rrc_decode = TRUE; /* Control whether decoding details of RAR UL grant or not */ static gboolean global_mac_lte_decode_rar_ul_grant = TRUE; +/* Forward declarations */ +void proto_reg_handoff_mac_lte(void); +void dissect_mac_lte(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree); + + +/* Heuristic dissection */ +static gboolean global_mac_lte_heur = FALSE; + +static gboolean dissect_mac_lte_heur(tvbuff_t *tvb, packet_info *pinfo, + proto_tree *tree) +{ + unsigned int offset = 0; + struct mac_lte_info *p_mac_lte_info; + tvbuff_t *mac_tvb; + guint8 tag = 0; + gboolean infoAlreadySet = FALSE; + + /* This is a heuristic dissector, which means we get all the UDP + * traffic not sent to a known dissector and not claimed by + * a heuristic dissector called before us! + */ + + if (!global_mac_lte_heur) { + return FALSE; + } + + /* If redissecting, use previous info struct (if available) */ + p_mac_lte_info = p_get_proto_data(pinfo->fd, proto_mac_lte); + if (p_mac_lte_info == NULL) { + /* Allocate new info struct for this frame */ + p_mac_lte_info = se_alloc0(sizeof(struct mac_lte_info)); + if (p_mac_lte_info == NULL) { + return FALSE; + } + infoAlreadySet = FALSE; + } + else { + infoAlreadySet = TRUE; + } + + /* Do this again on re-dissection to re-discover offset of actual PDU */ + + /* Needs to be at least as long as: + - the signature string + - fixed header bytes + - tag for data + - at least one byte of MAC PDU payload */ + if ((size_t)tvb_length_remaining(tvb, offset) < (strlen(MAC_LTE_START_STRING)+3+2)) { + return FALSE; + } + + /* OK, compare with signature string */ + if (tvb_strneql(tvb, offset, MAC_LTE_START_STRING, strlen(MAC_LTE_START_STRING)) != 0) { + return FALSE; + } + offset += strlen(MAC_LTE_START_STRING); + + /* Read fixed fields */ + p_mac_lte_info->radioType = tvb_get_guint8(tvb, offset++); + p_mac_lte_info->direction = tvb_get_guint8(tvb, offset++); + p_mac_lte_info->rntiType = tvb_get_guint8(tvb, offset++); + + /* Read optional fields */ + while (tag != MAC_LTE_PAYLOAD_TAG) { + /* Process next tag */ + tag = tvb_get_guint8(tvb, offset++); + switch (tag) { + case MAC_LTE_RNTI_TAG: + p_mac_lte_info->rnti = tvb_get_ntohs(tvb, offset); + offset += 2; + break; + case MAC_LTE_UEID_TAG: + p_mac_lte_info->ueid = tvb_get_ntohs(tvb, offset); + offset += 2; + break; + case MAC_LTE_SUBFRAME_TAG: + p_mac_lte_info->subframeNumber = tvb_get_ntohs(tvb, offset); + offset += 2; + break; + case MAC_LTE_PREDFINED_DATA_TAG: + p_mac_lte_info->isPredefinedData = tvb_get_guint8(tvb, offset); + offset++; + break; + case MAC_LTE_RETX_TAG: + p_mac_lte_info->reTxCount = tvb_get_guint8(tvb, offset); + offset++; + break; + case MAC_LTE_CRC_STATUS_TAG: + p_mac_lte_info->crcStatusValid = TRUE; + p_mac_lte_info->crcStatus = tvb_get_guint8(tvb, offset); + offset++; + break; + + case MAC_LTE_PAYLOAD_TAG: + /* Have reached data, so set payload length and get out of loop */ + p_mac_lte_info->length= tvb_length_remaining(tvb, offset); + continue; + + default: + /* It must be a recognised tag */ + return FALSE; + } + + if (!infoAlreadySet) { + /* Store info in packet */ + p_add_proto_data(pinfo->fd, proto_mac_lte, p_mac_lte_info); + } + } + + + /**************************************/ + /* OK, now dissect as MAC LTE */ + + /* Create tvb that starts at actual MAC PDU */ + mac_tvb = tvb_new_subset(tvb, offset, -1, tvb_reported_length(tvb)-offset); + dissect_mac_lte(mac_tvb, pinfo, tree); + return TRUE; +} /* Dissect a single Random Access Reponse body */ static gint dissect_rar_entry(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, @@ -1176,6 +1294,12 @@ void dissect_mac_lte(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) return; } + /* Clear info column */ + if (check_col(pinfo->cinfo, COL_INFO)) { + col_clear(pinfo->cinfo, COL_INFO); + } + + /*****************************************/ /* Show context information */ @@ -1739,6 +1863,23 @@ void proto_register_mac_lte(void) "Attempt to decode details of RAR UL grant field", "Attempt to decode details of RAR UL grant field", &global_mac_lte_decode_rar_ul_grant); + + prefs_register_bool_preference(mac_lte_module, "heuristic_mac_lte_over_udp", + "Try Heuristic LTE-MAC over UDP framing", + "When enabled, use heuristic dissector to find MAC-LTE frames sent with " + "UDP framing", + &global_mac_lte_heur); } +void +proto_reg_handoff_mac_lte(void) +{ + static dissector_handle_t mac_lte_handle; + if (!mac_lte_handle) { + mac_lte_handle = find_dissector("mac-lte"); + + /* Add as a heuristic UDP dissector */ + heur_dissector_add("udp", dissect_mac_lte_heur, proto_mac_lte); + } +} diff --git a/epan/dissectors/packet-mac-lte.h b/epan/dissectors/packet-mac-lte.h index 7a6ca04eed..fd5c8e3b38 100644 --- a/epan/dissectors/packet-mac-lte.h +++ b/epan/dissectors/packet-mac-lte.h @@ -75,3 +75,62 @@ typedef struct mac_lte_tap_info { guint8 number_of_rars; } mac_lte_tap_info; + + +/*****************************************************************/ +/* UDP framing format */ +/* ----------------------- */ +/* Several people have asked about dissecting MAC by framing */ +/* PDUs over IP. A suggested format over UDP has been */ +/* and implemented by this dissector, using the definitions */ +/* below. An example program showing you how to encode this */ +/* header and send LTE MAC PDUs on a UDP socket is available */ +/* from http://wiki.wireshark.org/MAC-LTE */ +/* */ +/* A heuristic dissected (enabled by a preference) will */ +/* recognise a signature at the beginning of these frames . */ +/* Until someone is using this format, suggestions for chage */ +/* are welcome. */ +/*****************************************************************/ + + +/* Signature. Rather than try to define a port for this, or make the + port number a preference, frames will start with this string (with no + terminating NULL */ +#define MAC_LTE_START_STRING "mac-lte" + +/* Fixed fields. This is followed by the following 3 mandatory fields: + - radioType (1 byte) + - direction (1 byte) + - rntiType (1 byte) + (where the allowed values are defined above */ + +/* Optional fields. Attaching this info to frames will allow you + to show you display/filter/plot/add-custom-columns on these fields, so should + be added if available. + The format is to have the tag, followed by the value (there is no length field, + its implicit from the tag) */ + +#define MAC_LTE_RNTI_TAG 0x02 +/* 2 bytes, network order */ + +#define MAC_LTE_UEID_TAG 0x03 +/* 2 bytes, network order */ + +#define MAC_LTE_SUBFRAME_TAG 0x04 +/* 2 bytes, network order */ + +#define MAC_LTE_PREDFINED_DATA_TAG 0x05 +/* 1 byte */ + +#define MAC_LTE_RETX_TAG 0x06 +/* 1 byte */ + +#define MAC_LTE_CRC_STATUS_TAG 0x07 +/* 1 byte */ + + +/* MAC PDU. Following this tag comes the actual MAC PDU (there is no length, the PDU + continues until the end of the frame) */ +#define MAC_LTE_PAYLOAD_TAG 0x01 + diff --git a/gtk/mac_lte_stat_dlg.c b/gtk/mac_lte_stat_dlg.c index 364ce251b9..b2cd9435df 100644 --- a/gtk/mac_lte_stat_dlg.c +++ b/gtk/mac_lte_stat_dlg.c @@ -37,6 +37,7 @@ #ifdef HAVE_SYS_TYPES_H #include <sys/types.h> #endif + #include <string.h> #include <gtk/gtk.h> @@ -45,19 +46,14 @@ #include <epan/packet_info.h> #include <epan/tap.h> #include <epan/dissectors/packet-mac-lte.h> -#include <epan/strutil.h> #include "../register.h" #include "../simple_dialog.h" -#include "../globals.h" #include "../stat_menu.h" -#include "../isprint.h" -#include "gtk/gtkglobals.h" #include "gtk/dlg_utils.h" #include "gtk/gui_stat_menu.h" #include "gtk/gui_utils.h" -#include "gtk/recent.h" #include "gtk/help_dlg.h" #include "gtk/main.h" @@ -256,6 +252,8 @@ static mac_lte_ep_t* alloc_mac_lte_ep(struct mac_lte_tap_info *si, packet_info * ep->next = NULL; + ep->iter_valid = FALSE; + return ep; } |