/* packet-llcgprs.c * Routines for Logical Link Control GPRS dissection ETSI 4.64(TS 101 351 V8.7.0) * Copyright 2000, Josef Korelus * * Wireshark - Network traffic analyzer * By Gerald Combs * Copyright 1998 Gerald Combs * * SPDX-License-Identifier: GPL-2.0-or-later */ #include "config.h" #include #include #include #include #include void proto_register_llcgprs(void); void proto_reg_handoff_llcgprs(void); #define I_FORMAT 1 #define S_FORMAT 2 #define UI_FORMAT 3 #define U_FORMAT 4 #define I_SACK 5 #define S_SACK 6 #define UI_MASK_FMT 0xe000 #define UI_MASK_SPB 0x1800 #define UI_MASK_NU 0x07fc #define UI_MASK_E 0x0002 #define UI_MASK_PM 0x0001 #define N202 4U #define CRC_LENGTH 3U #define UI_HDR_LENGTH 3U /* Initialize the protocol and registered fields */ static int proto_llcgprs; static int hf_llcgprs_pd; static int hf_llcgprs_fcs; static int hf_llcgprs_cr; static int hf_llcgprs_sapi; static int hf_llcgprs_sapib; static int hf_llcgprs_U_fmt; /* 3 upper bits in controlfield (UI format) */ static int hf_llcgprs_sp_bits; /* Spare bits in control field */ static int hf_llcgprs_NU; /* Transmited unconfirmed sequence number */ static int hf_llcgprs_E_bit; /* Encryption mode bit */ static int hf_llcgprs_PM_bit; static int hf_llcgprs_Un; static int hf_llcgprs_As; static int hf_llcgprs_ucom; static int hf_llcgprs_PF; static int hf_llcgprs_S_fmt; static int hf_llcgprs_NR; static int hf_llcgprs_sjsd; static int hf_llcgprs_k; static int hf_llcgprs_isack_ns; static int hf_llcgprs_isack_nr; static int hf_llcgprs_isack_sfb; static int hf_llcgprs_rbyte; static int hf_llcgprs_kmask; static int hf_llcgprs_ifmt; static int hf_llcgprs_Ai; static int hf_llcgprs_izerobit; static int hf_llcgprs_sspare; static int hf_llcgprs_xid_xl; static int hf_llcgprs_xid_type; static int hf_llcgprs_xid_len1; static int hf_llcgprs_xid_len2; static int hf_llcgprs_xid_spare; static int hf_llcgprs_xid_byte; static int hf_llcgprs_frmr_cf; static int hf_llcgprs_frmr_spare; static int hf_llcgprs_frmr_vs; static int hf_llcgprs_frmr_vr; static int hf_llcgprs_frmr_cr; static int hf_llcgprs_frmr_w4; static int hf_llcgprs_frmr_w3; static int hf_llcgprs_frmr_w2; static int hf_llcgprs_frmr_w1; static int hf_llcgprs_tom_rl; static int hf_llcgprs_tom_pd; static int hf_llcgprs_tom_header; static int hf_llcgprs_tom_data; static int hf_llcgprs_dummy_ui; /* Unnumbered Commands and Responses (U Frames) */ #define U_DM 0x01 #define U_DISC 0x04 #define U_UA 0x06 #define U_SABM 0x07 #define U_FRMR 0x08 #define U_XID 0x0B #define U_NULL 0x00 /* SAPI value constants */ #define SAPI_LLGMM 0x01 #define SAPI_TOM2 0x02 #define SAPI_LL3 0x03 #define SAPI_LL5 0x05 #define SAPI_LLSMS 0x07 #define SAPI_TOM8 0x08 #define SAPI_LL9 0x09 #define SAPI_LL11 0x0B /* Initialize the subtree pointers */ static int ett_llcgprs; static int ett_llcgprs_adf; static int ett_llcgprs_ctrlf; static int ett_llcgprs_ui; static int ett_llcgprs_sframe; static expert_field ei_llcgprs_no_info_field; static dissector_handle_t sndcp_xid_handle; static dissector_handle_t gprs_llc_handle; static bool ignore_cipher_bit; static dissector_table_t llcgprs_subdissector_table; static const value_string sapi_t[] = { { 0, "Reserved"}, { 1, "GPRS Mobility Management" }, { 2, "Tunneling of messages 2" }, { 3, "User data 3"}, { 4, "Reserved" }, { 5, "User data 5" }, { 6, "Reserved" }, { 7, "SMS" }, { 8, "Tunneling of messages 8" }, { 9, "User data 9" }, { 10, "Reserved" }, { 11, "User data 11" }, { 12, "Reserved" }, { 13, "Reserved" }, { 14, "Reserved" }, { 15, "Reserved" }, { 0, NULL }, }; static value_string_ext sapi_t_ext = VALUE_STRING_EXT_INIT(sapi_t); static const value_string sapi_abrv[] = { { 0, "Reserved 0"}, { 1, "LLGMM" }, { 2, "TOM2" }, { 3, "LL3"}, { 4, "Reserved 4" }, { 5, "LL5" }, { 6, "Reserved 6" }, { 7, "LLSMS" }, { 8, "TOM8" }, { 9, "LL9" }, { 10, "Reserved 10" }, { 11, "LL11" }, { 12, "Reserved 12" }, { 13, "Reserved 13" }, { 14, "Reserved 14" }, { 15, "Reserved 15" }, { 0, NULL } }; static value_string_ext sapi_abrv_ext = VALUE_STRING_EXT_INIT(sapi_abrv); static const true_false_string a_bit = { "To solicit an acknowledgement from the peer LLE. ", "The peer LLE is not requested to send an acknowledgment." }; static const true_false_string pd_bit = { "Invalid frame PD=1", "OK" }; static const true_false_string e_bit = { "encrypted frame", "non encrypted frame" }; static const true_false_string pm_bit = { "FCS covers the frame header and information fields", "FCS covers only the frame header and first N202 octets of the information field" }; static const true_false_string cr_bit = { "DownLink/UpLink = Command/Response", "DownLink/UpLink = Response/Command" }; /* bits are swaped comparing with "Table 3" in ETSI document */ static const value_string pme[] = { { 0, "unprotected,non-ciphered information" }, { 1, "protected, non-ciphered information" }, { 2, "unprotected,ciphered information"}, { 3, "protected, ciphered information" }, { 0, NULL } }; static const value_string xid_param_type_str[] = { { 0x0, "Version (LLC version number)" }, { 0x1, "IOV-UI (ciphering Input offset value for UI frames)" }, { 0x2, "IOV-I (ciphering Input offset value for I frames)" }, { 0x3, "T200 (retransmission timeout)" }, { 0x4, "N200 (max number of retransmissions)" }, { 0x5, "N201-U (max info field length for U and UI frames)" }, { 0x6, "N201-I (max info field length for I frames)" }, { 0x7, "mD (I frame buffer size in the DL direction)" }, { 0x8, "mU (I frame buffer size in the UL direction)" }, { 0x9, "kD (window size in the DL direction)" }, { 0xA, "kU (window size in the UL direction)" }, { 0xB, "Layer-3 Parameters" }, { 0xC, "Reset" }, { 0, NULL } }; static value_string_ext xid_param_type_str_ext = VALUE_STRING_EXT_INIT(xid_param_type_str); static const value_string tompd_formats[] = { { 0x0, "Not specified" }, { 0x1, "TIA/EIA-136" }, { 0x2, "RRLP" }, { 0x3, "Reserved value 3" }, { 0x4, "Reserved value 4" }, { 0x5, "Reserved value 5" }, { 0x6, "Reserved value 6" }, { 0x7, "Reserved value 7" }, { 0x8, "Reserved value 8" }, { 0x9, "Reserved value 9" }, { 0xA, "Reserved value 10" }, { 0xB, "Reserved value 11" }, { 0xC, "Reserved value 12" }, { 0xD, "Reserved value 13" }, { 0xE, "Reserved value 14" }, { 0xF, "Reserved for extension" }, { 0, NULL } }; static const value_string cr_formats_unnumb[]= { { 0x1, "DM-response" }, { 0x4, "DISC-command" }, { 0x6, "UA-response" }, { 0x7, "SABM" }, { 0x8, "FRMR" }, { 0xb, "XID" }, { 0, NULL } }; static const value_string cr_formats_ipluss[] = { { 0x0, "RR" }, { 0x1, "ACK" }, { 0x2, "RNR" }, { 0x3, "SACK" }, { 0, NULL } }; /* CRC24 table - FCS */ static uint32_t tbl_crc24[256] = { 0x00000000, 0x00d6a776, 0x00f64557, 0x0020e221, 0x00b78115, 0x00612663, 0x0041c442, 0x00976334, 0x00340991, 0x00e2aee7, 0x00c24cc6, 0x0014ebb0, 0x00838884, 0x00552ff2, 0x0075cdd3, 0x00a36aa5, 0x00681322, 0x00beb454, 0x009e5675, 0x0048f103, 0x00df9237, 0x00093541, 0x0029d760, 0x00ff7016, 0x005c1ab3, 0x008abdc5, 0x00aa5fe4, 0x007cf892, 0x00eb9ba6, 0x003d3cd0, 0x001ddef1, 0x00cb7987, 0x00d02644, 0x00068132, 0x00266313, 0x00f0c465, 0x0067a751, 0x00b10027, 0x0091e206, 0x00474570, 0x00e42fd5, 0x003288a3, 0x00126a82, 0x00c4cdf4, 0x0053aec0, 0x008509b6, 0x00a5eb97, 0x00734ce1, 0x00b83566, 0x006e9210, 0x004e7031, 0x0098d747, 0x000fb473, 0x00d91305, 0x00f9f124, 0x002f5652, 0x008c3cf7, 0x005a9b81, 0x007a79a0, 0x00acded6, 0x003bbde2, 0x00ed1a94, 0x00cdf8b5, 0x001b5fc3, 0x00fb4733, 0x002de045, 0x000d0264, 0x00dba512, 0x004cc626, 0x009a6150, 0x00ba8371, 0x006c2407, 0x00cf4ea2, 0x0019e9d4, 0x00390bf5, 0x00efac83, 0x0078cfb7, 0x00ae68c1, 0x008e8ae0, 0x00582d96, 0x00935411, 0x0045f367, 0x00651146, 0x00b3b630, 0x0024d504, 0x00f27272, 0x00d29053, 0x00043725, 0x00a75d80, 0x0071faf6, 0x005118d7, 0x0087bfa1, 0x0010dc95, 0x00c67be3, 0x00e699c2, 0x00303eb4, 0x002b6177, 0x00fdc601, 0x00dd2420, 0x000b8356, 0x009ce062, 0x004a4714, 0x006aa535, 0x00bc0243, 0x001f68e6, 0x00c9cf90, 0x00e92db1, 0x003f8ac7, 0x00a8e9f3, 0x007e4e85, 0x005eaca4, 0x00880bd2, 0x00437255, 0x0095d523, 0x00b53702, 0x00639074, 0x00f4f340, 0x00225436, 0x0002b617, 0x00d41161, 0x00777bc4, 0x00a1dcb2, 0x00813e93, 0x005799e5, 0x00c0fad1, 0x00165da7, 0x0036bf86, 0x00e018f0, 0x00ad85dd, 0x007b22ab, 0x005bc08a, 0x008d67fc, 0x001a04c8, 0x00cca3be, 0x00ec419f, 0x003ae6e9, 0x00998c4c, 0x004f2b3a, 0x006fc91b, 0x00b96e6d, 0x002e0d59, 0x00f8aa2f, 0x00d8480e, 0x000eef78, 0x00c596ff, 0x00133189, 0x0033d3a8, 0x00e574de, 0x007217ea, 0x00a4b09c, 0x008452bd, 0x0052f5cb, 0x00f19f6e, 0x00273818, 0x0007da39, 0x00d17d4f, 0x00461e7b, 0x0090b90d, 0x00b05b2c, 0x0066fc5a, 0x007da399, 0x00ab04ef, 0x008be6ce, 0x005d41b8, 0x00ca228c, 0x001c85fa, 0x003c67db, 0x00eac0ad, 0x0049aa08, 0x009f0d7e, 0x00bfef5f, 0x00694829, 0x00fe2b1d, 0x00288c6b, 0x00086e4a, 0x00dec93c, 0x0015b0bb, 0x00c317cd, 0x00e3f5ec, 0x0035529a, 0x00a231ae, 0x007496d8, 0x005474f9, 0x0082d38f, 0x0021b92a, 0x00f71e5c, 0x00d7fc7d, 0x00015b0b, 0x0096383f, 0x00409f49, 0x00607d68, 0x00b6da1e, 0x0056c2ee, 0x00806598, 0x00a087b9, 0x007620cf, 0x00e143fb, 0x0037e48d, 0x001706ac, 0x00c1a1da, 0x0062cb7f, 0x00b46c09, 0x00948e28, 0x0042295e, 0x00d54a6a, 0x0003ed1c, 0x00230f3d, 0x00f5a84b, 0x003ed1cc, 0x00e876ba, 0x00c8949b, 0x001e33ed, 0x008950d9, 0x005ff7af, 0x007f158e, 0x00a9b2f8, 0x000ad85d, 0x00dc7f2b, 0x00fc9d0a, 0x002a3a7c, 0x00bd5948, 0x006bfe3e, 0x004b1c1f, 0x009dbb69, 0x0086e4aa, 0x005043dc, 0x0070a1fd, 0x00a6068b, 0x003165bf, 0x00e7c2c9, 0x00c720e8, 0x0011879e, 0x00b2ed3b, 0x00644a4d, 0x0044a86c, 0x00920f1a, 0x00056c2e, 0x00d3cb58, 0x00f32979, 0x00258e0f, 0x00eef788, 0x003850fe, 0x0018b2df, 0x00ce15a9, 0x0059769d, 0x008fd1eb, 0x00af33ca, 0x007994bc, 0x00dafe19, 0x000c596f, 0x002cbb4e, 0x00fa1c38, 0x006d7f0c, 0x00bbd87a, 0x009b3a5b, 0x004d9d2d }; #define INIT_CRC24 0xffffff static uint32_t crc_calc(uint32_t fcs, tvbuff_t *tvb, unsigned len) { const unsigned char *cp; cp = tvb_get_ptr(tvb, 0, len); while (len--) fcs = (fcs >> 8) ^ tbl_crc24[(fcs ^ *cp++) & 0xff]; return fcs; } typedef enum { FCS_VALID, FCS_NOT_VALID, FCS_NOT_VALID_DUE_TO_CIPHERING, FCS_NOT_COMPUTED } fcs_status_t; /* sub-dissector for XID data */ static void llc_gprs_dissect_xid(tvbuff_t *tvb, packet_info *pinfo, proto_item *llcgprs_tree) { uint8_t xid_param_len = 0, byte1 = 0, byte2 = 0, tmp = 0; unsigned item_len = 0; unsigned location = 0; unsigned loop_counter = 0; proto_tree *uinfo_tree = NULL; proto_tree *xid_tree = NULL; unsigned info_len; info_len = tvb_reported_length(tvb); xid_tree = proto_tree_add_subtree_format(llcgprs_tree, tvb, 0, info_len, ett_llcgprs_ui, NULL, "Information Field: Length = %u", info_len); while (location < info_len) { /* parse the XID parameters */ byte1 = tvb_get_uint8(tvb, location); if (byte1 & 0x80) { uint8_t xid_param_len_high = 0; uint8_t xid_param_len_low = 0; byte2 = tvb_get_uint8(tvb, location + 1); /* XL bit is set - length is continued in second byte */ xid_param_len_high = byte1 & 0x03; xid_param_len_low = byte2 & 0xFC; /* bit shift the rest of the length */ xid_param_len_low = xid_param_len_low >> 2; xid_param_len_low = xid_param_len_low & 0x3F; xid_param_len_high = xid_param_len_high << 6; xid_param_len_high = xid_param_len_high & 0xC0; /* combine the two */ xid_param_len = xid_param_len_high | xid_param_len_low; item_len = xid_param_len + 2; } else { xid_param_len = byte1 & 0x3; item_len = xid_param_len + 1; } tmp = byte1 & 0x7C; tmp = tmp >> 2; if (tmp == 0xB) /* L3 XID parameters, call the SNDCP-XID dissector */ { tvbuff_t *sndcp_xid_tvb; uint8_t sndcp_xid_offset; uinfo_tree = proto_tree_add_subtree(xid_tree, tvb, location, item_len, ett_llcgprs_ui, NULL, "XID parameter Type: L3 parameters"); proto_tree_add_uint(uinfo_tree, hf_llcgprs_xid_xl, tvb, location, 1, byte1); proto_tree_add_uint(uinfo_tree, hf_llcgprs_xid_type, tvb, location, 1, byte1); proto_tree_add_uint(uinfo_tree, hf_llcgprs_xid_len1, tvb, location, 1, byte1); if (byte1 & 0x80) { proto_tree_add_uint(uinfo_tree, hf_llcgprs_xid_len2, tvb, location+1, 1, byte2); proto_tree_add_uint(uinfo_tree, hf_llcgprs_xid_spare, tvb, location+1, 1, byte2); sndcp_xid_offset = 2; } else { sndcp_xid_offset = 1; } if (xid_param_len) { sndcp_xid_tvb = tvb_new_subset_length (tvb, location+sndcp_xid_offset, xid_param_len); if(sndcp_xid_handle) { call_dissector(sndcp_xid_handle, sndcp_xid_tvb, pinfo, uinfo_tree); } } location += item_len; } else { if (( xid_param_len > 0 ) && ( xid_param_len <=4 )) { uint32_t value = 0; uint8_t i; for (i=1;i<=xid_param_len;i++) { value <<= 8; value |= (uint32_t)tvb_get_uint8(tvb, location+i ); } uinfo_tree = proto_tree_add_subtree_format(xid_tree, tvb, location, item_len, ett_llcgprs_ui, NULL, "XID Parameter Type: %s - Value: %u", val_to_str_ext(tmp, &xid_param_type_str_ext, "Reserved Type:%X"), value); } else { uinfo_tree = proto_tree_add_subtree_format(xid_tree, tvb, location, item_len, ett_llcgprs_ui, NULL, "XID Parameter Type: %s", val_to_str_ext(tmp, &xid_param_type_str_ext, "Reserved Type:%X")); } proto_tree_add_uint(uinfo_tree, hf_llcgprs_xid_xl, tvb, location, 1, byte1); proto_tree_add_uint(uinfo_tree, hf_llcgprs_xid_type, tvb, location, 1, byte1); proto_tree_add_uint(uinfo_tree, hf_llcgprs_xid_len1, tvb, location, 1, byte1); if (byte1 & 0x80) { /* length continued into byte 2 */ proto_tree_add_uint(uinfo_tree, hf_llcgprs_xid_len2, tvb, location, 1, byte2); proto_tree_add_uint(uinfo_tree, hf_llcgprs_xid_spare, tvb, location, 1, byte2); /* be sure to account for the second byte of length */ location++; } location++; for (loop_counter = 0; loop_counter < xid_param_len; loop_counter++) { /* grab the information in the XID param */ byte2 = tvb_get_uint8(tvb, location); proto_tree_add_uint(uinfo_tree, hf_llcgprs_xid_byte, tvb, location, 1, byte2); location++; } } } } /* shortest dummy UI command as per TS 44.064 Section 6.4.2.2 */ static const uint8_t dummy_ui_cmd[] = { 0x43, 0xc0, 0x01, 0x2b, 0x2b, 0x2b }; static int dissect_llcgprs(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_) { unsigned offset = 0; uint8_t addr_fld=0, sapi=0, ctrl_fld_fb=0, frame_format, tmp=0; uint16_t epm = 0, nu=0, ctrl_fld_ui_s=0; proto_item *ti, *addres_field_item; proto_tree *llcgprs_tree=NULL , *ad_f_tree =NULL, *ctrl_f_tree=NULL, *ui_tree=NULL; tvbuff_t *next_tvb; unsigned length, captured_length; unsigned crc_length = 0, llc_data_length; uint32_t fcs=0; uint32_t fcs_calc=0; fcs_status_t fcs_status; uint16_t ns = 0; uint16_t nr = 0; uint8_t k = 0; uint8_t m_bits = 0; unsigned info_len; proto_tree *uinfo_tree = NULL; bool ciphered_ui_frame = false; if (!tvb_memeql(tvb, 0, dummy_ui_cmd, sizeof(dummy_ui_cmd))) { proto_tree_add_boolean(tree, hf_llcgprs_dummy_ui, tvb, offset, tvb_captured_length(tvb), true); return tvb_captured_length(tvb); } col_set_str(pinfo->cinfo, COL_PROTOCOL, "GPRS-LLC"); /* llc_data_length includes the header and the payload */ llc_data_length = length = tvb_reported_length(tvb); if (length >= CRC_LENGTH) { /* * The packet is big enough to have a CRC. */ llc_data_length -= CRC_LENGTH; } else { /* * The packet isn't big enough to have a CRC; claim * the data length is 0. */ llc_data_length = 0; } captured_length = tvb_captured_length(tvb); /* * Address field. */ addr_fld = tvb_get_uint8(tvb, offset); offset++; if (addr_fld > 128 ) { col_set_str(pinfo->cinfo, COL_INFO, "Invalid packet - Protocol Discriminator bit is set to 1"); return offset; } sapi = addr_fld & 0xF; col_add_fstr(pinfo->cinfo, COL_INFO, "SAPI: %s", val_to_str_ext(sapi, &sapi_abrv_ext, "Unknown (%u)")); /* In the interest of speed, if "tree" is NULL, don't do any work not necessary to generate protocol tree items. */ if (tree) { ti = proto_tree_add_protocol_format(tree, proto_llcgprs, tvb, 0, -1, "MS-SGSN LLC (Mobile Station - Serving GPRS Support Node Logical Link Control) SAPI: %s", val_to_str_ext(sapi, &sapi_t_ext, "Unknown (%u)")); llcgprs_tree = proto_item_add_subtree(ti, ett_llcgprs); /* add an item to the subtree, see section 1.6 for more information */ addres_field_item = proto_tree_add_uint_format(llcgprs_tree, hf_llcgprs_sapi, tvb, 0, 1, sapi, "Address field SAPI: %s", val_to_str_ext(sapi, &sapi_abrv_ext, "Unknown (%u)")); ad_f_tree = proto_item_add_subtree(addres_field_item, ett_llcgprs_adf); proto_tree_add_boolean(ad_f_tree, hf_llcgprs_pd, tvb, 0, 1, addr_fld ); proto_tree_add_boolean(ad_f_tree, hf_llcgprs_cr, tvb, 0, 1, addr_fld ); proto_tree_add_uint(ad_f_tree, hf_llcgprs_sapib, tvb, 0, 1, addr_fld ); } /* * Control field. */ ctrl_fld_fb = tvb_get_uint8(tvb, offset); if (ctrl_fld_fb < 0xC0) { frame_format = (ctrl_fld_fb < 0x80)? I_FORMAT : S_FORMAT; } else { frame_format = (ctrl_fld_fb < 0xe0 )? UI_FORMAT : U_FORMAT; } switch (frame_format) { case I_FORMAT: col_append_str(pinfo->cinfo, COL_INFO, ", I, "); ns = tvb_get_ntohs(tvb, offset); ns = (ns >> 4)& 0x01FF; nr = ctrl_fld_ui_s = tvb_get_ntohs(tvb, offset + 1); nr = (nr >> 2) & 0x01FF; epm = ctrl_fld_ui_s & 0x3; col_append_str(pinfo->cinfo, COL_INFO, val_to_str(epm, cr_formats_ipluss, "Unknown (%d)")); col_append_fstr(pinfo->cinfo, COL_INFO, ", N(S) = %u", ns); col_append_fstr(pinfo->cinfo, COL_INFO, ", N(R) = %u", nr); if (tree) { uint32_t tmpx; ctrl_f_tree = proto_tree_add_subtree_format(llcgprs_tree, tvb, offset, 3, ett_llcgprs_sframe, NULL, "Information format: %s: N(S) = %u, N(R) = %u", val_to_str(epm, cr_formats_ipluss, "Unknown (%d)"), ns, nr); /* retrieve the second octet */ tmpx = tvb_get_ntohs(tvb, offset) << 16; proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_ifmt, tvb, offset, 3, tmpx); proto_tree_add_boolean(ctrl_f_tree, hf_llcgprs_Ai, tvb, offset, 3, tmpx); proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_izerobit, tvb, offset, 3, tmpx); tmpx = ns << 12; proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_isack_ns, tvb, offset, 3, tmpx); tmpx = nr << 2; proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_isack_nr, tvb, offset, 3, tmpx); proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_isack_sfb, tvb, offset, 3, ctrl_fld_ui_s); } /* advance to either R Bitmap or Payload */ offset += 3; /* check to see if epm is SACK - meaning this is an ISACK frame */ if (epm == 0x03) { uint8_t kmask; /* SACK Frame */ k = kmask = tvb_get_uint8(tvb, offset); k = k & 0x1F; /* advance past the k field */ offset++; /* the real value of k is actually k + 1 */ /* account for the off by one representation */ k++; col_append_fstr(pinfo->cinfo, COL_INFO, ", k = %u", k); if (tree) { uint8_t loop_count = 0; uint8_t r_byte = 0; unsigned location = offset; ctrl_f_tree = proto_tree_add_subtree_format(llcgprs_tree, tvb, (offset-1), (k+1), ett_llcgprs_sframe, NULL, "SACK FRAME: k = %u", k); proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_kmask, tvb, offset-1, 1, kmask); proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_k, tvb, offset-1, 1, k); /* display the R Bitmap */ for (loop_count = 0; loop_count < k; loop_count++) { r_byte = tvb_get_uint8(tvb, location); proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_rbyte, tvb, location, 1, r_byte); location++; } } /* step past the R Bitmap */ offset += k; } crc_length = llc_data_length; break; case S_FORMAT: col_append_str(pinfo->cinfo, COL_INFO, ", S, "); nu = ctrl_fld_ui_s = tvb_get_ntohs(tvb, offset); epm = ctrl_fld_ui_s & 0x3; nu = (nu >>2)&0x01FF; col_append_str(pinfo->cinfo, COL_INFO, val_to_str(epm, cr_formats_ipluss, "Unknown (%d)")); col_append_fstr(pinfo->cinfo, COL_INFO, ", N(R) = %u", nu); if (tree) { static int * const s_formats[] = { &hf_llcgprs_S_fmt, &hf_llcgprs_As, &hf_llcgprs_sspare, &hf_llcgprs_NR, &hf_llcgprs_sjsd, NULL }; proto_tree_add_bitmask_text(llcgprs_tree, tvb, offset, 2, "Supervisory format: ", NULL, ett_llcgprs_sframe, s_formats, ENC_BIG_ENDIAN, 0); } offset += 2; if ((ctrl_fld_ui_s & 0x03) == 0x03) /* It is a SACK frame */ { /* TODO: length is fudged - it is not correct */ uint32_t sack_length = llc_data_length - offset; if (tree) { unsigned loop_count; uint8_t r_byte; uint16_t location = offset; ctrl_f_tree = proto_tree_add_subtree_format(llcgprs_tree, tvb, offset, sack_length, ett_llcgprs_sframe, NULL, "SACK FRAME: length = %u", sack_length); /* display the R Bitmap */ for (loop_count = 0; loop_count < sack_length; loop_count++) { r_byte = tvb_get_uint8(tvb, location); proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_rbyte, tvb, location, 1, r_byte); location++; } /* step past the r bitmap */ offset += sack_length; } } crc_length = llc_data_length; break; case UI_FORMAT: col_append_str(pinfo->cinfo, COL_INFO, ", UI, "); nu = ctrl_fld_ui_s = tvb_get_ntohs(tvb, offset); epm = ctrl_fld_ui_s & 0x3; nu = (nu >>2)&0x01FF; /* If the frame is ciphered, the calculated FCS will not be valid (unless it has been unciphered) */ if (epm & UI_MASK_E) { ciphered_ui_frame = true; } if ((epm & UI_MASK_PM)== 0) { /* FCS covers at maximum the LLC header and N202 bytes */ crc_length = MIN(UI_HDR_LENGTH + N202, llc_data_length); } else { crc_length = llc_data_length; } col_append_str(pinfo->cinfo, COL_INFO, val_to_str(epm, pme, "Unknown (%d)")); col_append_fstr(pinfo->cinfo, COL_INFO, ", N(U) = %u", nu); if (tree) { static int * const i_formats[] = { &hf_llcgprs_U_fmt, &hf_llcgprs_sp_bits, &hf_llcgprs_NU, &hf_llcgprs_E_bit, &hf_llcgprs_PM_bit, NULL }; proto_tree_add_bitmask_text(llcgprs_tree, tvb, offset, 2, "Unconfirmed Information format - UI: ", NULL, ett_llcgprs_ctrlf, i_formats, ENC_BIG_ENDIAN, 0); } offset += 2; break; case U_FORMAT: col_append_str(pinfo->cinfo, COL_INFO, ", U, "); tmp = ctrl_fld_fb & 0xf; col_append_str(pinfo->cinfo, COL_INFO, val_to_str(tmp, cr_formats_unnumb, "Unknown/invalid code:%X")); ui_tree = proto_tree_add_subtree_format(llcgprs_tree, tvb, offset, (llc_data_length-1), ett_llcgprs_ui, NULL, "Unnumbered frame: %s", val_to_str(tmp, cr_formats_unnumb, "Unknown/invalid code:%X")); proto_tree_add_uint(ui_tree, hf_llcgprs_Un, tvb, offset, 1, ctrl_fld_fb); proto_tree_add_boolean(ui_tree, hf_llcgprs_PF, tvb, offset, 1, ctrl_fld_fb); proto_tree_add_uint(ui_tree, hf_llcgprs_ucom, tvb, offset, 1, ctrl_fld_fb); offset += 1; crc_length = llc_data_length; break; } /* * FCS. */ if (captured_length >= length && length >= CRC_LENGTH) { /* * We have all the packet data, including the full FCS, * so we can compute the FCS. */ fcs_calc = crc_calc ( INIT_CRC24 , tvb, crc_length ); fcs_calc = ~fcs_calc; fcs_calc &= 0xffffff; fcs = tvb_get_letoh24(tvb, llc_data_length); if ( fcs_calc == fcs ) { fcs_status = FCS_VALID; proto_tree_add_uint_format_value(llcgprs_tree, hf_llcgprs_fcs, tvb, llc_data_length, CRC_LENGTH, fcs_calc&0xffffff, "0x%06x (correct)", fcs_calc&0xffffff); } else { if (ciphered_ui_frame) { fcs_status = FCS_NOT_VALID_DUE_TO_CIPHERING; proto_tree_add_uint_format_value(llcgprs_tree, hf_llcgprs_fcs, tvb, llc_data_length, CRC_LENGTH, fcs, "0x%06x (incorrect, maybe due to ciphering, calculated 0x%06x)", fcs, fcs_calc ); } else { fcs_status = FCS_NOT_VALID; proto_tree_add_uint_format_value(llcgprs_tree, hf_llcgprs_fcs, tvb, llc_data_length, CRC_LENGTH, fcs, "0x%06x (incorrect, should be 0x%06x)", fcs, fcs_calc ); } } } else { /* We don't have enough data to compute the FCS. */ fcs_status = FCS_NOT_COMPUTED; proto_tree_add_uint_format_value(llcgprs_tree, hf_llcgprs_fcs, tvb, 0, 0, 0, "FCS: Not enough data to compute the FCS"); } /* * Information field. */ switch (frame_format) { case I_FORMAT: if ((sapi == SAPI_TOM2) || (sapi == SAPI_TOM8)) { /* if SAPI is TOM do other parsing */ if (tree) { uint8_t tom_byte = 0; uint8_t remaining_length = 0; uint8_t tom_pd = 0; int loop_counter = 0; tom_byte = tvb_get_uint8(tvb, offset); remaining_length = (tom_byte >> 4) & 0x0F; tom_pd = tom_byte & 0x0F; ctrl_f_tree = proto_tree_add_subtree_format(llcgprs_tree, tvb, offset, (llc_data_length-offset), ett_llcgprs_sframe, NULL, "TOM Envelope - Protocol: %s", val_to_str(tom_pd, tompd_formats, "Unknown (%d)")); proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_tom_rl, tvb, offset, 1, tom_byte); proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_tom_pd, tvb, offset, 1, tom_byte); /* step past the TOM header first byte */ offset++; /* TOM remaining length field value 0x0F is reserved for extension */ if (remaining_length != 0x0F) { /* parse the rest of the TOM header */ for (loop_counter = 0; loop_counter < remaining_length; loop_counter++) { tom_byte = tvb_get_uint8(tvb, offset); proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_tom_header, tvb, offset, 1, tom_byte); /* step to the next byte */ offset++; } remaining_length = llc_data_length - offset; /* parse the TOM message capsule */ for (loop_counter = 0; loop_counter < remaining_length; loop_counter++) { tom_byte = tvb_get_uint8(tvb, offset); proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_tom_data, tvb, offset, 1, tom_byte); /* step to the next byte */ offset++; } } } } else { /* otherwise - call a subdissector */ next_tvb = tvb_new_subset_length(tvb, offset, (llc_data_length-offset)); if (!dissector_try_uint(llcgprs_subdissector_table, sapi, next_tvb, pinfo, tree)) /* if no subdissector is found, call the data dissector */ { call_data_dissector(next_tvb, pinfo, tree); } } break; case S_FORMAT: /* should parse the rest of the supervisory message based on type */ /* if SAPI is TOM do other parsing */ if ((sapi == SAPI_TOM2) || (sapi == SAPI_TOM8)) { if (tree) { uint8_t tom_byte = 0; uint8_t remaining_length = 0; uint8_t tom_pd = 0; int loop_counter = 0; tom_byte = tvb_get_uint8(tvb, offset); remaining_length = (tom_byte >> 4) & 0x0F; tom_pd = tom_byte & 0x0F; ctrl_f_tree = proto_tree_add_subtree_format(llcgprs_tree, tvb, offset, (llc_data_length-offset), ett_llcgprs_sframe, NULL, "TOM Envelope - Protocol: %s", val_to_str(tom_pd, tompd_formats, "Unknown (%d)")); proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_tom_rl, tvb, offset, 1, tom_byte); proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_tom_pd, tvb, offset, 1, tom_byte); /* step past the TOM header first byte */ offset++; /* TOM remaining length field value 0x0F is reserved for extension */ if (remaining_length != 0x0F) { /* parse the rest of the TOM header */ for (loop_counter = 0; loop_counter < remaining_length; loop_counter++) { tom_byte = tvb_get_uint8(tvb, offset); proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_tom_header, tvb, offset, 1, tom_byte); /* step to the next byte */ offset++; } /* Amount of frame left from offset to crc */ remaining_length = llc_data_length - offset; /* parse the TOM message capsule */ for (loop_counter = 0; loop_counter < remaining_length; loop_counter++) { tom_byte = tvb_get_uint8(tvb, offset); proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_tom_data, tvb, offset, 1, tom_byte); /* step to the next byte */ offset++; } } } } else if (llc_data_length>offset) { /* otherwise - call a subdissector */ next_tvb = tvb_new_subset_length(tvb, offset, (llc_data_length-offset)); if (!dissector_try_uint(llcgprs_subdissector_table, sapi, next_tvb, pinfo, tree)) { call_data_dissector(next_tvb, pinfo, tree); } } break; case UI_FORMAT: next_tvb = tvb_new_subset_length(tvb, offset, (llc_data_length-offset)); if ((ignore_cipher_bit && (fcs_status == FCS_VALID)) || !(epm & 0x2)) { /* Either we're ignoring the cipher bit * (because the bit is set but the * data is unciphered), and the data has * a valid FCS, or the cipher * bit isn't set (indicating that the * data is unciphered). Try dissecting * it with a subdissector. */ /* if SAPI is TOM do other parsing */ if ((sapi == SAPI_TOM2) || (sapi == SAPI_TOM8)) { if (tree) { uint8_t tom_byte = 0; uint8_t remaining_length = 0; uint8_t tom_pd = 0; int loop_counter = 0; tom_byte = tvb_get_uint8(tvb, offset); remaining_length = (tom_byte >> 4) & 0x0F; tom_pd = tom_byte & 0x0F; ctrl_f_tree = proto_tree_add_subtree_format(llcgprs_tree, tvb, offset, (llc_data_length-offset), ett_llcgprs_sframe, NULL, "TOM Envelope - Protocol: %s", val_to_str(tom_pd, tompd_formats, "Unknown (%d)")); proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_tom_rl, tvb, offset, 1, tom_byte); proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_tom_pd, tvb, offset, 1, tom_byte); /* step past the TOM header first byte */ offset++; /* TOM remaining length field value 0x0F is reserved for extension */ if (remaining_length != 0x0F) { /* parse the rest of the TOM header */ for (loop_counter = 0; loop_counter < remaining_length; loop_counter++) { tom_byte = tvb_get_uint8(tvb, offset); proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_tom_header, tvb, offset, 1, tom_byte); /* step to the next byte */ offset++; } /* Amount of frame left from offset to crc */ remaining_length = llc_data_length - offset; /* parse the TOM message capsule */ for (loop_counter = 0; loop_counter < remaining_length; loop_counter++) { tom_byte = tvb_get_uint8(tvb, offset); proto_tree_add_uint(ctrl_f_tree, hf_llcgprs_tom_data, tvb, offset, 1, tom_byte); /* step to the next byte */ offset++; } } } } else if (llc_data_length>offset) { /* otherwise - call a subdissector */ if (!dissector_try_uint(llcgprs_subdissector_table, sapi, next_tvb, pinfo, tree)) { call_data_dissector(next_tvb, pinfo, tree); } } } else { /* ciphered information - just parse it as data */ call_data_dissector(next_tvb, pinfo, tree); } break; case U_FORMAT: m_bits = ctrl_fld_fb & 0x0F; info_len = llc_data_length - offset; switch (m_bits) { case U_DM: case U_DISC: case U_NULL: /* These frames SHOULD NOT have an info field */ proto_tree_add_expert(llcgprs_tree, pinfo, &ei_llcgprs_no_info_field, tvb, offset, (llc_data_length-2)); break; case U_UA: /* This frame MAY or MAY NOT have an info field */ /* Info field, if it exists, consists of XID parameters */ if (tree) { tvbuff_t *xid_tvb; xid_tvb = tvb_new_subset_length (tvb, offset, info_len); llc_gprs_dissect_xid(xid_tvb, pinfo, llcgprs_tree); } break; case U_SABM: case U_XID: /* These frames do have info fields consisting of XID parameters */ /* Info field consists of XID parameters */ if (tree) { tvbuff_t *xid_tvb; xid_tvb = tvb_new_subset_length (tvb, offset, info_len); llc_gprs_dissect_xid(xid_tvb, pinfo, llcgprs_tree); } break; case U_FRMR: /* This frame has a special format info field */ if (tree) { uint32_t fld_vars = 0; uint16_t cf_byte = 0; int loop_counter = 0; int location = 0; ui_tree = proto_tree_add_subtree_format(llcgprs_tree, tvb, offset, (llc_data_length-2), ett_llcgprs_ui, NULL, "Information Field: Length = %u", info_len); uinfo_tree = proto_tree_add_subtree(ui_tree, tvb, offset, 6, ett_llcgprs_ui, NULL, "Rejected Frame Control Field"); location = offset; for (loop_counter = 0; loop_counter < 3; loop_counter++) { /* display the rejected frame control field */ cf_byte = tvb_get_ntohs(tvb, location); proto_tree_add_uint(uinfo_tree, hf_llcgprs_frmr_cf, tvb, location, 2, cf_byte); location += 2; } uinfo_tree = proto_tree_add_subtree(ui_tree, tvb, location, 4, ett_llcgprs_ui, NULL, "Information Field Data"); fld_vars = tvb_get_ntohl(tvb, location); proto_tree_add_uint(uinfo_tree, hf_llcgprs_frmr_spare, tvb, location, 4, fld_vars); proto_tree_add_uint(uinfo_tree, hf_llcgprs_frmr_vs, tvb, location, 2, fld_vars); proto_tree_add_uint(uinfo_tree, hf_llcgprs_frmr_vr, tvb, (location + 1), 2, fld_vars); proto_tree_add_uint(uinfo_tree, hf_llcgprs_frmr_cr, tvb, (location + 2), 1, fld_vars); proto_tree_add_uint(uinfo_tree, hf_llcgprs_frmr_w4, tvb, (location + 3), 1, fld_vars); proto_tree_add_uint(uinfo_tree, hf_llcgprs_frmr_w3, tvb, (location + 3), 1, fld_vars); proto_tree_add_uint(uinfo_tree, hf_llcgprs_frmr_w2, tvb, (location + 3), 1, fld_vars); proto_tree_add_uint(uinfo_tree, hf_llcgprs_frmr_w1, tvb, (location + 3), 1, fld_vars); } break; default: break; } break; } return tvb_captured_length(tvb); } /* Register the protocol with Wireshark */ void proto_register_llcgprs(void) { /* Setup list of header fields See Section 1.6.1 for details */ static hf_register_info hf[] = { { &hf_llcgprs_sapi, { "SAPI", "llcgprs.sapi", FT_UINT8, BASE_DEC|BASE_EXT_STRING, &sapi_abrv_ext, 0x0, "Service Access Point Identifier", HFILL }}, { &hf_llcgprs_pd, { "Protocol Discriminator_bit", "llcgprs.pd", FT_BOOLEAN, 8, TFS(&pd_bit), 0x80, "Protocol Discriminator bit (should be 0)", HFILL }}, { &hf_llcgprs_fcs, { "FCS", "llcgprs.fcs", FT_UINT24, BASE_HEX, NULL, 0, NULL, HFILL }}, { &hf_llcgprs_sjsd, { "Supervisory function bits", "llcgprs.s1s2", FT_UINT16, BASE_HEX, VALS(cr_formats_ipluss), 0x3, NULL, HFILL }}, { &hf_llcgprs_cr, { "Command/Response bit", "llcgprs.cr", FT_BOOLEAN, 8, TFS(&cr_bit), 0x40, NULL, HFILL }}, { &hf_llcgprs_sapib, { "SAPI", "llcgprs.sapib", FT_UINT8, BASE_DEC|BASE_EXT_STRING , &sapi_t_ext, 0xf, "Service Access Point Identifier", HFILL }}, { &hf_llcgprs_U_fmt, { "UI format", "llcgprs.ui", FT_UINT16, BASE_HEX, NULL, UI_MASK_FMT, "UI frame format", HFILL }}, { &hf_llcgprs_Un, { "U format", "llcgprs.u", FT_UINT8, BASE_HEX, NULL, 0xe0, "U frame format", HFILL }}, { &hf_llcgprs_sp_bits, { "Spare bits", "llcgprs.ui_sp_bit", FT_UINT16, BASE_HEX, NULL, UI_MASK_SPB, NULL, HFILL }}, { &hf_llcgprs_NU, { "N(U)", "llcgprs.nu", FT_UINT16, BASE_DEC, NULL, UI_MASK_NU, "Transmitted unconfirmed sequence number", HFILL }}, { &hf_llcgprs_E_bit, { "E bit", "llcgprs.e", FT_BOOLEAN, 16, TFS(&e_bit), UI_MASK_E, "Encryption mode bit", HFILL }}, { &hf_llcgprs_PM_bit, { "PM bit", "llcgprs.pm", FT_BOOLEAN, 16, TFS(&pm_bit), UI_MASK_PM, "Protected mode bit", HFILL }}, { &hf_llcgprs_As, { "Ackn request bit", "llcgprs.as", FT_BOOLEAN, 16, TFS(&a_bit), 0x2000, "Acknowledgement request bit A", HFILL }}, { &hf_llcgprs_PF, { "P/F bit", "llcgprs.pf", FT_BOOLEAN, 8, NULL, 0x10, "Poll/Final bit", HFILL }}, { &hf_llcgprs_ucom, { "Command/Response", "llcgprs.ucom", FT_UINT8, BASE_HEX, VALS(cr_formats_unnumb), 0xf, "Commands and Responses", HFILL }}, { &hf_llcgprs_NR, { "Receive sequence number", "llcgprs.nr", FT_UINT16, BASE_DEC, NULL, UI_MASK_NU, "Receive sequence number N(R)", HFILL }}, { &hf_llcgprs_S_fmt, { "S format", "llcgprs.s", FT_UINT16, BASE_HEX, NULL, 0xc000, "Supervisory format S", HFILL }}, { &hf_llcgprs_kmask, { "ignored", "llcgprs.kmask", FT_UINT8, BASE_DEC, NULL, 0xE0, NULL, HFILL }}, { &hf_llcgprs_k, { "k", "llcgprs.k", FT_UINT8, BASE_DEC, NULL, 0x1F, "k counter", HFILL }}, { &hf_llcgprs_isack_ns, { "N(S)", "llcgprs.sackns", FT_UINT24, BASE_DEC, NULL, 0x1FF000, NULL, HFILL }}, { &hf_llcgprs_isack_nr, { "N(R)", "llcgprs.sacknr", FT_UINT24, BASE_DEC, NULL, 0x0007FC, NULL, HFILL }}, { &hf_llcgprs_isack_sfb, { "Supervisory function bits", "llcgprs.sacksfb", FT_UINT24, BASE_HEX, VALS(cr_formats_ipluss), 0x000003, NULL, HFILL }}, { &hf_llcgprs_ifmt, { "I Format", "llcgprs.ifmt", FT_UINT24, BASE_HEX, NULL, 0x800000, "I Fmt Bit", HFILL }}, { &hf_llcgprs_Ai, { "Ackn request bit", "llcgprs.ai", FT_BOOLEAN, 24, TFS(&a_bit), 0x400000, "Acknowledgement request bit A", HFILL }}, { &hf_llcgprs_izerobit, { "Spare", "llcgprs.iignore", FT_UINT24, BASE_DEC, NULL, 0x200000, "Ignore Bit", HFILL }}, { &hf_llcgprs_sspare, { "Spare", "llcgprs.sspare", FT_UINT16, BASE_DEC, NULL, 0x1800, "Ignore Bit", HFILL }}, { &hf_llcgprs_rbyte, { "R Bitmap Bits", "llcgprs.sackrbits", FT_UINT8, BASE_HEX, NULL, 0xFF, NULL, HFILL }}, /* XID Parameter Parsing Info */ { &hf_llcgprs_xid_xl, { "XL Bit", "llcgprs.xidxl", FT_UINT8, BASE_HEX, NULL, 0x80, NULL, HFILL }}, { &hf_llcgprs_xid_type, { "Type", "llcgprs.xidtype", FT_UINT8, BASE_DEC, NULL, 0x7C, NULL, HFILL }}, { &hf_llcgprs_xid_len1, { "Length", "llcgprs.xidlen1", FT_UINT8, BASE_DEC, NULL, 0x03, NULL, HFILL }}, { &hf_llcgprs_xid_len2, { "Length continued", "llcgprs.xidlen2", FT_UINT8, BASE_DEC, NULL, 0xFC, NULL, HFILL }}, { &hf_llcgprs_xid_spare, { "Spare", "llcgprs.xidspare", FT_UINT8, BASE_HEX, NULL, 0x03, "Ignore", HFILL }}, { &hf_llcgprs_xid_byte, { "Parameter Byte", "llcgprs.xidbyte", FT_UINT8, BASE_HEX, NULL, 0xFF, "Data", HFILL }}, /* FRMR Parsing Information */ { &hf_llcgprs_frmr_cf, { "Control Field Octet", "llcgprs.frmrrfcf", FT_UINT16, BASE_DEC, NULL, 0xFFFF, "Rejected Frame CF", HFILL }}, { &hf_llcgprs_frmr_spare, { "X", "llcgprs.frmrspare", FT_UINT32, BASE_HEX, NULL, 0xF00400F0, "Filler", HFILL }}, { &hf_llcgprs_frmr_vs, { "V(S)", "llcgprs.frmrvs", FT_UINT32, BASE_DEC, NULL, 0x0FF80000, "Current send state variable", HFILL }}, { &hf_llcgprs_frmr_vr, { "V(R)", "llcgprs.frmrvr", FT_UINT32, BASE_DEC, NULL, 0x0003FE00, "Current receive state variable", HFILL }}, { &hf_llcgprs_frmr_cr, { "C/R", "llcgprs.frmrcr", FT_UINT32, BASE_DEC, NULL, 0x00000100, "Rejected command response", HFILL }}, { &hf_llcgprs_frmr_w4, { "W4", "llcgprs.frmrw4", FT_UINT32, BASE_DEC, NULL, 0x00000008, "LLE was in ABM when rejecting", HFILL }}, { &hf_llcgprs_frmr_w3, { "W3", "llcgprs.frmrw3", FT_UINT32, BASE_DEC, NULL, 0x00000004, "Undefined control field", HFILL }}, { &hf_llcgprs_frmr_w2, { "W2", "llcgprs.frmrw2", FT_UINT32, BASE_DEC, NULL, 0x00000002, "Info exceeded N201", HFILL }}, { &hf_llcgprs_frmr_w1, { "W1", "llcgprs.frmrw1", FT_UINT32, BASE_DEC, NULL, 0x00000001, "Invalid - info not permitted", HFILL }}, { &hf_llcgprs_tom_rl, { "Remaining Length of TOM Protocol Header", "llcgprs.romrl", FT_UINT8, BASE_DEC, NULL, 0xF0, "RL", HFILL }}, { &hf_llcgprs_tom_pd, { "TOM Protocol Discriminator", "llcgprs.tompd", FT_UINT8, BASE_HEX, NULL, 0x0F, "TPD", HFILL }}, { &hf_llcgprs_tom_header, { "TOM Header Byte", "llcgprs.tomhead", FT_UINT8, BASE_HEX, NULL, 0xFF, "thb", HFILL }}, { &hf_llcgprs_tom_data, { "TOM Message Capsule Byte", "llcgprs.tomdata", FT_UINT8, BASE_HEX, NULL, 0xFF, "tdb", HFILL }}, { &hf_llcgprs_dummy_ui, { "Dummy UI Command", "llcgprs.dummy_ui", FT_BOOLEAN, BASE_NONE, NULL, 0x00, NULL, HFILL }}, }; /* Setup protocol subtree array */ static int *ett[] = { &ett_llcgprs, &ett_llcgprs_adf, &ett_llcgprs_ctrlf, &ett_llcgprs_ui, &ett_llcgprs_sframe, }; static ei_register_info ei[] = { { &ei_llcgprs_no_info_field, { "llcgprs.no_info_field", PI_PROTOCOL, PI_WARN, "No Information Field", EXPFILL }}, }; module_t *llcgprs_module; expert_module_t* expert_llcgprs; /* Register the protocol name and description */ proto_llcgprs = proto_register_protocol("Logical Link Control GPRS", "GPRS-LLC", "llcgprs"); llcgprs_subdissector_table = register_dissector_table("llcgprs.sapi", "GPRS LLC SAPI", proto_llcgprs, FT_UINT8, BASE_HEX); /* Required function calls to register the header fields and subtrees used */ proto_register_field_array(proto_llcgprs, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); expert_llcgprs = expert_register_protocol(proto_llcgprs); expert_register_field_array(expert_llcgprs, ei, array_length(ei)); gprs_llc_handle = register_dissector("llcgprs", dissect_llcgprs, proto_llcgprs); llcgprs_module = prefs_register_protocol ( proto_llcgprs, NULL ); prefs_register_bool_preference ( llcgprs_module, "autodetect_cipher_bit", "Autodetect cipher bit", "Whether to autodetect the cipher bit (because it might be set on unciphered data)", &ignore_cipher_bit ); } void proto_reg_handoff_llcgprs(void) { /* make sure that the top level can call this dissector */ dissector_add_uint("wtap_encap", WTAP_ENCAP_GPRS_LLC, gprs_llc_handle); sndcp_xid_handle = find_dissector_add_dependency("sndcpxid", proto_llcgprs); } /* * Editor modelines - https://www.wireshark.org/tools/modelines.html * * Local variables: * c-basic-offset: 8 * tab-width: 8 * indent-tabs-mode: t * End: * * vi: set shiftwidth=8 tabstop=8 noexpandtab: * :indentSize=8:tabSize=8:noTabs=false: */