Neels Hofmeyr | 17518fe | 2017-06-20 04:35:06 +0200 | [diff] [blame] | 1 | /*! \file gsm0480.c |
| 2 | * Format functions for GSM 04.80. */ |
Holger Hans Peter Freyther | 55aea50 | 2010-09-30 18:30:41 +0800 | [diff] [blame] | 3 | /* |
| 4 | * (C) 2010 by Holger Hans Peter Freyther <zecke@selfish.org> |
| 5 | * (C) 2009 by Mike Haben <michael.haben@btinternet.com> |
Harald Welte | b1a35d6 | 2018-06-16 18:34:52 +0200 | [diff] [blame] | 6 | * (C) 2018 by Harald Welte <laforge@gnumonks.org> |
Holger Hans Peter Freyther | 55aea50 | 2010-09-30 18:30:41 +0800 | [diff] [blame] | 7 | * |
| 8 | * All Rights Reserved |
| 9 | * |
Harald Welte | e08da97 | 2017-11-13 01:00:26 +0900 | [diff] [blame] | 10 | * SPDX-License-Identifier: GPL-2.0+ |
| 11 | * |
Holger Hans Peter Freyther | 55aea50 | 2010-09-30 18:30:41 +0800 | [diff] [blame] | 12 | * This program is free software; you can redistribute it and/or modify |
| 13 | * it under the terms of the GNU General Public License as published by |
| 14 | * the Free Software Foundation; either version 2 of the License, or |
| 15 | * (at your option) any later version. |
| 16 | * |
| 17 | * This program is distributed in the hope that it will be useful, |
| 18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 20 | * GNU General Public License for more details. |
| 21 | * |
| 22 | * You should have received a copy of the GNU General Public License along |
| 23 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 24 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 25 | * |
| 26 | */ |
| 27 | |
Vadim Yanitskiy | 30cfeeb | 2018-08-03 05:44:00 +0700 | [diff] [blame] | 28 | #include <osmocom/gsm/gsm48.h> |
Pablo Neira Ayuso | 8341934 | 2011-03-22 16:36:13 +0100 | [diff] [blame] | 29 | #include <osmocom/gsm/gsm0480.h> |
| 30 | #include <osmocom/gsm/gsm_utils.h> |
Holger Hans Peter Freyther | 55aea50 | 2010-09-30 18:30:41 +0800 | [diff] [blame] | 31 | |
Pablo Neira Ayuso | 8341934 | 2011-03-22 16:36:13 +0100 | [diff] [blame] | 32 | #include <osmocom/core/logging.h> |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 33 | |
Pablo Neira Ayuso | 8341934 | 2011-03-22 16:36:13 +0100 | [diff] [blame] | 34 | #include <osmocom/gsm/protocol/gsm_04_08.h> |
| 35 | #include <osmocom/gsm/protocol/gsm_04_80.h> |
Holger Hans Peter Freyther | 55aea50 | 2010-09-30 18:30:41 +0800 | [diff] [blame] | 36 | |
| 37 | #include <string.h> |
Vadim Yanitskiy | 52e4412 | 2018-06-11 03:51:11 +0700 | [diff] [blame] | 38 | #include <errno.h> |
Holger Hans Peter Freyther | 55aea50 | 2010-09-30 18:30:41 +0800 | [diff] [blame] | 39 | |
Harald Welte | b1a35d6 | 2018-06-16 18:34:52 +0200 | [diff] [blame] | 40 | const struct value_string gsm0480_comp_type_names[] = { |
| 41 | { GSM0480_CTYPE_INVOKE, "Invoke" }, |
| 42 | { GSM0480_CTYPE_RETURN_RESULT, "ReturnResult" }, |
| 43 | { GSM0480_CTYPE_RETURN_ERROR, "ReturnError" }, |
| 44 | { GSM0480_CTYPE_REJECT, "Reject" }, |
| 45 | { 0, NULL } |
| 46 | }; |
| 47 | |
| 48 | const struct value_string gsm0480_op_code_names[] = { |
| 49 | { GSM0480_OP_CODE_REGISTER_SS, "RegisterSS" }, |
| 50 | { GSM0480_OP_CODE_ERASE_SS, "EraseSS" }, |
| 51 | { GSM0480_OP_CODE_ACTIVATE_SS, "ActivateSS" }, |
| 52 | { GSM0480_OP_CODE_DEACTIVATE_SS, "DeactivateSS" }, |
Max | e035572 | 2018-12-19 13:52:28 +0100 | [diff] [blame] | 53 | { GSM0480_OP_CODE_INTERROGATE_SS, "InterrogateSS" }, |
Harald Welte | b1a35d6 | 2018-06-16 18:34:52 +0200 | [diff] [blame] | 54 | { GSM0480_OP_CODE_NOTIFY_SS, "NotifySS" }, |
| 55 | { GSM0480_OP_CODE_REGISTER_PASSWORD, "RegisterPassword" }, |
| 56 | { GSM0480_OP_CODE_GET_PASSWORD, "GetPassword" }, |
| 57 | { GSM0480_OP_CODE_PROCESS_USS_DATA, "ProcessUSSD" }, |
Max | e035572 | 2018-12-19 13:52:28 +0100 | [diff] [blame] | 58 | { GSM0480_OP_CODE_FORWARD_CHECK_SS_IND, "ForwardCheckSSind" }, |
Harald Welte | b1a35d6 | 2018-06-16 18:34:52 +0200 | [diff] [blame] | 59 | { GSM0480_OP_CODE_PROCESS_USS_REQ, "ProcessUssReq" }, |
| 60 | { GSM0480_OP_CODE_USS_REQUEST, "UssRequest" }, |
| 61 | { GSM0480_OP_CODE_USS_NOTIFY, "UssNotify" }, |
| 62 | { GSM0480_OP_CODE_FORWARD_CUG_INFO, "ForwardCugInfo" }, |
| 63 | { GSM0480_OP_CODE_SPLIT_MPTY, "SplitMPTY" }, |
| 64 | { GSM0480_OP_CODE_RETRIEVE_MPTY, "RetrieveMPTY" }, |
| 65 | { GSM0480_OP_CODE_HOLD_MPTY, "HoldMPTY" }, |
| 66 | { GSM0480_OP_CODE_BUILD_MPTY, "BuildMPTY" }, |
| 67 | { GSM0480_OP_CODE_FORWARD_CHARGE_ADVICE, "ForwardChargeAdvice" }, |
| 68 | { 0, NULL } |
| 69 | }; |
| 70 | |
Holger Hans Peter Freyther | 55aea50 | 2010-09-30 18:30:41 +0800 | [diff] [blame] | 71 | /* wrap an invoke around it... the other way around |
| 72 | * |
| 73 | * 1.) Invoke Component tag |
| 74 | * 2.) Invoke ID Tag |
| 75 | * 3.) Operation |
| 76 | * 4.) Data |
| 77 | */ |
| 78 | int gsm0480_wrap_invoke(struct msgb *msg, int op, int link_id) |
| 79 | { |
| 80 | /* 3. operation */ |
Max | 84fb5bb | 2018-11-08 13:23:59 +0100 | [diff] [blame] | 81 | msgb_tlv1_push(msg, GSM0480_OPERATION_CODE, op); |
Holger Hans Peter Freyther | 55aea50 | 2010-09-30 18:30:41 +0800 | [diff] [blame] | 82 | |
| 83 | /* 2. invoke id tag */ |
Max | 84fb5bb | 2018-11-08 13:23:59 +0100 | [diff] [blame] | 84 | msgb_tlv1_push(msg, GSM0480_COMPIDTAG_INVOKE_ID, link_id); |
Holger Hans Peter Freyther | 55aea50 | 2010-09-30 18:30:41 +0800 | [diff] [blame] | 85 | |
| 86 | /* 1. component tag */ |
| 87 | msgb_wrap_with_TL(msg, GSM0480_CTYPE_INVOKE); |
| 88 | |
| 89 | return 0; |
| 90 | } |
| 91 | |
| 92 | /* wrap the GSM 04.08 Facility IE around it */ |
| 93 | int gsm0480_wrap_facility(struct msgb *msg) |
| 94 | { |
| 95 | msgb_wrap_with_TL(msg, GSM0480_IE_FACILITY); |
| 96 | |
| 97 | return 0; |
| 98 | } |
| 99 | |
| 100 | struct msgb *gsm0480_create_unstructuredSS_Notify(int alertPattern, const char *text) |
| 101 | { |
| 102 | struct msgb *msg; |
| 103 | uint8_t *seq_len_ptr, *ussd_len_ptr, *data; |
Holger Hans Peter Freyther | 47aa482 | 2013-07-07 13:54:53 +0200 | [diff] [blame] | 104 | int len; |
Holger Hans Peter Freyther | 55aea50 | 2010-09-30 18:30:41 +0800 | [diff] [blame] | 105 | |
Vadim Yanitskiy | 39a36d0 | 2018-08-03 03:52:16 +0700 | [diff] [blame] | 106 | msg = gsm0480_msgb_alloc_name("TS 04.80 USSD Notify"); |
Holger Hans Peter Freyther | 55aea50 | 2010-09-30 18:30:41 +0800 | [diff] [blame] | 107 | if (!msg) |
| 108 | return NULL; |
| 109 | |
| 110 | /* SEQUENCE { */ |
| 111 | msgb_put_u8(msg, GSM_0480_SEQUENCE_TAG); |
| 112 | seq_len_ptr = msgb_put(msg, 1); |
| 113 | |
| 114 | /* DCS { */ |
| 115 | msgb_put_u8(msg, ASN1_OCTET_STRING_TAG); |
| 116 | msgb_put_u8(msg, 1); |
| 117 | msgb_put_u8(msg, 0x0F); |
| 118 | /* } DCS */ |
| 119 | |
| 120 | /* USSD-String { */ |
| 121 | msgb_put_u8(msg, ASN1_OCTET_STRING_TAG); |
| 122 | ussd_len_ptr = msgb_put(msg, 1); |
| 123 | data = msgb_put(msg, 0); |
Jacob Erlbeck | 1d7f3b5 | 2013-08-12 17:07:53 +0200 | [diff] [blame] | 124 | gsm_7bit_encode_n_ussd(data, msgb_tailroom(msg), text, &len); |
Holger Hans Peter Freyther | 47aa482 | 2013-07-07 13:54:53 +0200 | [diff] [blame] | 125 | msgb_put(msg, len); |
| 126 | ussd_len_ptr[0] = len; |
Holger Hans Peter Freyther | 55aea50 | 2010-09-30 18:30:41 +0800 | [diff] [blame] | 127 | /* USSD-String } */ |
| 128 | |
| 129 | /* alertingPattern { */ |
| 130 | msgb_put_u8(msg, ASN1_OCTET_STRING_TAG); |
| 131 | msgb_put_u8(msg, 1); |
| 132 | msgb_put_u8(msg, alertPattern); |
| 133 | /* } alertingPattern */ |
| 134 | |
| 135 | seq_len_ptr[0] = 3 + 2 + ussd_len_ptr[0] + 3; |
| 136 | /* } SEQUENCE */ |
| 137 | |
| 138 | return msg; |
| 139 | } |
| 140 | |
| 141 | struct msgb *gsm0480_create_notifySS(const char *text) |
| 142 | { |
| 143 | struct msgb *msg; |
| 144 | uint8_t *data, *tmp_len; |
| 145 | uint8_t *seq_len_ptr, *cal_len_ptr, *opt_len_ptr, *nam_len_ptr; |
Holger Hans Peter Freyther | 47aa482 | 2013-07-07 13:54:53 +0200 | [diff] [blame] | 146 | int len; |
Holger Hans Peter Freyther | 55aea50 | 2010-09-30 18:30:41 +0800 | [diff] [blame] | 147 | |
| 148 | len = strlen(text); |
| 149 | if (len < 1 || len > 160) |
| 150 | return NULL; |
| 151 | |
Vadim Yanitskiy | 39a36d0 | 2018-08-03 03:52:16 +0700 | [diff] [blame] | 152 | msg = gsm0480_msgb_alloc_name("TS 04.80 NotifySS"); |
Holger Hans Peter Freyther | 55aea50 | 2010-09-30 18:30:41 +0800 | [diff] [blame] | 153 | if (!msg) |
| 154 | return NULL; |
| 155 | |
| 156 | msgb_put_u8(msg, GSM_0480_SEQUENCE_TAG); |
| 157 | seq_len_ptr = msgb_put(msg, 1); |
| 158 | |
| 159 | /* ss_code for CNAP { */ |
| 160 | msgb_put_u8(msg, 0x81); |
| 161 | msgb_put_u8(msg, 1); |
| 162 | msgb_put_u8(msg, 0x19); |
| 163 | /* } ss_code */ |
| 164 | |
| 165 | |
| 166 | /* nameIndicator { */ |
| 167 | msgb_put_u8(msg, 0xB4); |
| 168 | nam_len_ptr = msgb_put(msg, 1); |
| 169 | |
| 170 | /* callingName { */ |
| 171 | msgb_put_u8(msg, 0xA0); |
| 172 | opt_len_ptr = msgb_put(msg, 1); |
| 173 | msgb_put_u8(msg, 0xA0); |
| 174 | cal_len_ptr = msgb_put(msg, 1); |
| 175 | |
| 176 | /* namePresentationAllowed { */ |
| 177 | /* add the DCS value */ |
| 178 | msgb_put_u8(msg, 0x80); |
| 179 | msgb_put_u8(msg, 1); |
| 180 | msgb_put_u8(msg, 0x0F); |
| 181 | |
| 182 | /* add the lengthInCharacters */ |
| 183 | msgb_put_u8(msg, 0x81); |
| 184 | msgb_put_u8(msg, 1); |
| 185 | msgb_put_u8(msg, strlen(text)); |
| 186 | |
| 187 | /* add the actual string */ |
| 188 | msgb_put_u8(msg, 0x82); |
| 189 | tmp_len = msgb_put(msg, 1); |
| 190 | data = msgb_put(msg, 0); |
Jacob Erlbeck | 1d7f3b5 | 2013-08-12 17:07:53 +0200 | [diff] [blame] | 191 | gsm_7bit_encode_n_ussd(data, msgb_tailroom(msg), text, &len); |
Holger Hans Peter Freyther | 47aa482 | 2013-07-07 13:54:53 +0200 | [diff] [blame] | 192 | tmp_len[0] = len; |
| 193 | msgb_put(msg, len); |
Holger Hans Peter Freyther | 55aea50 | 2010-09-30 18:30:41 +0800 | [diff] [blame] | 194 | |
| 195 | /* }; namePresentationAllowed */ |
| 196 | |
Holger Hans Peter Freyther | 47aa482 | 2013-07-07 13:54:53 +0200 | [diff] [blame] | 197 | cal_len_ptr[0] = 3 + 3 + 2 + len; |
Holger Hans Peter Freyther | 55aea50 | 2010-09-30 18:30:41 +0800 | [diff] [blame] | 198 | opt_len_ptr[0] = cal_len_ptr[0] + 2; |
| 199 | /* }; callingName */ |
| 200 | |
| 201 | nam_len_ptr[0] = opt_len_ptr[0] + 2; |
| 202 | /* ); nameIndicator */ |
| 203 | |
| 204 | /* write the lengths... */ |
| 205 | seq_len_ptr[0] = 3 + nam_len_ptr[0] + 2; |
| 206 | |
| 207 | return msg; |
| 208 | } |
| 209 | |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 210 | /* Forward declarations */ |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 211 | static int parse_ss(const struct gsm48_hdr *hdr, |
| 212 | uint16_t len, struct ss_request *req); |
Vadim Yanitskiy | c30431f | 2017-07-29 04:47:42 +0600 | [diff] [blame] | 213 | static int parse_ss_facility(const uint8_t *ss_facility, uint16_t len, |
| 214 | struct ss_request *req); |
Vadim Yanitskiy | b41c70f | 2018-01-17 12:10:07 +0600 | [diff] [blame] | 215 | static int parse_ss_info_elements(const uint8_t *ss_ie, uint16_t len, |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 216 | struct ss_request *req); |
Holger Hans Peter Freyther | 49ad500 | 2010-10-11 09:06:47 +0200 | [diff] [blame] | 217 | static int parse_ss_invoke(const uint8_t *invoke_data, uint16_t length, |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 218 | struct ss_request *req); |
Vadim Yanitskiy | 7f16c44 | 2017-07-29 05:05:54 +0600 | [diff] [blame] | 219 | static int parse_ss_return_result(const uint8_t *rr_data, uint16_t length, |
| 220 | struct ss_request *req); |
| 221 | static int parse_process_uss_data(const uint8_t *uss_req_data, uint16_t length, |
| 222 | struct ss_request *req); |
Holger Hans Peter Freyther | 49ad500 | 2010-10-11 09:06:47 +0200 | [diff] [blame] | 223 | static int parse_process_uss_req(const uint8_t *uss_req_data, uint16_t length, |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 224 | struct ss_request *req); |
| 225 | static int parse_ss_for_bs_req(const uint8_t *ss_req_data, |
| 226 | uint16_t length, |
| 227 | struct ss_request *req); |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 228 | |
Vadim Yanitskiy | 52e4412 | 2018-06-11 03:51:11 +0700 | [diff] [blame] | 229 | /*! Get pointer to the IE of a given type |
| 230 | * \param[in] hdr Pointer to the message starting from header |
| 231 | * \param[in] msg_len Length of the whole message + header |
| 232 | * \param[out] ie External pointer to be set |
| 233 | * \param[out] ie_len External IE length variable |
| 234 | * \param[in] ie_tag Tag value of the required IE |
| 235 | * \returns 0 in case of success, otherwise -ERRNO |
| 236 | * |
| 237 | * This function iterates over existing IEs within a given |
| 238 | * message (depending on its type), and looks for the one with |
| 239 | * given \ref ie_tag value. If the IE is found, the external |
| 240 | * pointer pointed by \ref ie will be set to its value part |
| 241 | * (omitting TL), and \ref ie_len will be set to the length. |
| 242 | * Otherwise, e.g. in case of parsing error, both \ref ie |
| 243 | * and \ref ie_len are set to NULL and 0 respectively. |
| 244 | */ |
| 245 | int gsm0480_extract_ie_by_tag(const struct gsm48_hdr *hdr, uint16_t msg_len, |
| 246 | uint8_t **ie, uint16_t *ie_len, uint8_t ie_tag) |
| 247 | { |
| 248 | uint8_t pdisc, msg_type; |
| 249 | uint8_t *tlv, len; |
| 250 | |
| 251 | /* Init external variables */ |
| 252 | *ie_len = 0; |
| 253 | *ie = NULL; |
| 254 | |
| 255 | /* Drop incomplete / corrupted messages */ |
| 256 | if (msg_len < sizeof(*hdr)) |
| 257 | return -EINVAL; |
| 258 | |
| 259 | pdisc = gsm48_hdr_pdisc(hdr); |
| 260 | msg_type = gsm48_hdr_msg_type(hdr); |
| 261 | |
| 262 | /* Drop non-SS related messages */ |
| 263 | if (pdisc != GSM48_PDISC_NC_SS) |
| 264 | return -EINVAL; |
| 265 | |
| 266 | len = msg_len - sizeof(*hdr); |
| 267 | tlv = (uint8_t *) hdr->data; |
| 268 | |
| 269 | /* Parse a message depending on its type */ |
| 270 | switch (msg_type) { |
| 271 | /* See table 2.5: RELEASE COMPLETE message content */ |
| 272 | case GSM0480_MTYPE_RELEASE_COMPLETE: |
| 273 | /* See tables 2.3 and 2.4: REGISTER message content */ |
| 274 | case GSM0480_MTYPE_REGISTER: |
| 275 | /* Iterate over TLV-based IEs */ |
| 276 | while (len > 2) { |
| 277 | if (tlv[0] == ie_tag) { |
| 278 | *ie_len = tlv[1]; |
| 279 | *ie = tlv + 2; |
| 280 | return 0; |
| 281 | } |
| 282 | |
| 283 | len -= tlv[1] + 2; |
| 284 | tlv += tlv[1] + 2; |
| 285 | continue; |
| 286 | } |
| 287 | |
| 288 | /* The Facility IE is mandatory for REGISTER */ |
| 289 | if (msg_type == GSM0480_MTYPE_REGISTER) |
| 290 | if (ie_tag == GSM0480_IE_FACILITY) |
| 291 | return -EINVAL; |
| 292 | break; |
| 293 | |
| 294 | /* See table 2.2: FACILITY message content */ |
| 295 | case GSM0480_MTYPE_FACILITY: |
| 296 | /* There is no other IEs */ |
| 297 | if (ie_tag != GSM0480_IE_FACILITY) |
| 298 | break; |
| 299 | |
| 300 | /* Mandatory LV-based Facility IE */ |
| 301 | if (len < 2) |
| 302 | return -EINVAL; |
| 303 | |
| 304 | *ie_len = tlv[0]; |
| 305 | *ie = tlv + 1; |
| 306 | return 0; |
| 307 | |
| 308 | default: |
| 309 | /* Wrong message type, out of specs */ |
| 310 | return -EINVAL; |
| 311 | } |
| 312 | |
| 313 | return 0; |
| 314 | } |
| 315 | |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 316 | /* Decode a mobile-originated USSD-request message */ |
Holger Hans Peter Freyther | daa653f | 2010-10-11 07:56:06 +0200 | [diff] [blame] | 317 | int gsm0480_decode_ussd_request(const struct gsm48_hdr *hdr, uint16_t len, |
| 318 | struct ussd_request *req) |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 319 | { |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 320 | struct ss_request ss; |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 321 | int rc = 0; |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 322 | |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 323 | memset(&ss, 0, sizeof(ss)); |
| 324 | |
Holger Hans Peter Freyther | 8ac0486 | 2010-10-11 08:08:58 +0200 | [diff] [blame] | 325 | if (len < sizeof(*hdr) + 2) { |
| 326 | LOGP(0, LOGL_DEBUG, "USSD Request is too short.\n"); |
| 327 | return 0; |
| 328 | } |
| 329 | |
Neels Hofmeyr | 282e908 | 2016-03-14 16:06:46 +0100 | [diff] [blame] | 330 | if (gsm48_hdr_pdisc(hdr) == GSM48_PDISC_NC_SS) { |
Holger Hans Peter Freyther | daa653f | 2010-10-11 07:56:06 +0200 | [diff] [blame] | 331 | req->transaction_id = hdr->proto_discr & 0x70; |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 332 | |
| 333 | ss.transaction_id = req->transaction_id; |
Vadim Yanitskiy | 7689e0f | 2018-01-17 03:23:39 +0600 | [diff] [blame] | 334 | rc = parse_ss(hdr, len - sizeof(*hdr), &ss); |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 335 | |
| 336 | /* convert from ss_request to legacy ussd_request */ |
| 337 | req->transaction_id = ss.transaction_id; |
| 338 | req->invoke_id = ss.invoke_id; |
| 339 | if (ss.ussd_text[0] == 0xFF) |
| 340 | req->text[0] = '\0'; |
| 341 | else { |
| 342 | memcpy(req->text, ss.ussd_text, sizeof(req->text)); |
| 343 | req->text[sizeof(req->text)-1] = '\0'; |
| 344 | } |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 345 | } |
| 346 | |
| 347 | if (!rc) |
| 348 | LOGP(0, LOGL_DEBUG, "Error occurred while parsing received USSD!\n"); |
| 349 | |
| 350 | return rc; |
| 351 | } |
| 352 | |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 353 | /* Decode a mobile-originated SS request message */ |
| 354 | int gsm0480_decode_ss_request(const struct gsm48_hdr *hdr, uint16_t len, |
| 355 | struct ss_request *req) |
| 356 | { |
Vadim Yanitskiy | f07c58c | 2018-01-17 03:42:16 +0600 | [diff] [blame] | 357 | uint8_t pdisc; |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 358 | |
Vadim Yanitskiy | f07c58c | 2018-01-17 03:42:16 +0600 | [diff] [blame] | 359 | /** |
| 360 | * Check Protocol Discriminator |
| 361 | * see TS GSM 04.07 and GSM 04.80 |
| 362 | */ |
| 363 | pdisc = gsm48_hdr_pdisc(hdr); |
| 364 | if (pdisc != GSM48_PDISC_NC_SS) { |
| 365 | LOGP(0, LOGL_ERROR, "Dropping message with " |
| 366 | "unsupported pdisc=%02x\n", pdisc); |
| 367 | return 0; |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 368 | } |
| 369 | |
Vadim Yanitskiy | f07c58c | 2018-01-17 03:42:16 +0600 | [diff] [blame] | 370 | /* GSM 04.80 3.3 Transaction Identifier */ |
| 371 | req->transaction_id = hdr->proto_discr & 0x70; |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 372 | |
Vadim Yanitskiy | f07c58c | 2018-01-17 03:42:16 +0600 | [diff] [blame] | 373 | /* Parse SS request */ |
| 374 | return parse_ss(hdr, len - sizeof(*hdr), req); |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 375 | } |
| 376 | |
| 377 | static int parse_ss(const struct gsm48_hdr *hdr, uint16_t len, struct ss_request *req) |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 378 | { |
| 379 | int rc = 1; |
Neels Hofmeyr | a95ee5e | 2016-10-10 22:46:20 +0200 | [diff] [blame] | 380 | uint8_t msg_type = hdr->msg_type & 0x3F; /* message-type - section 3.4 */ |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 381 | |
Vadim Yanitskiy | fd744ce | 2018-01-17 03:31:15 +0600 | [diff] [blame] | 382 | /** |
| 383 | * GSM 04.80 Section 2.5 'Release complete' Table 2.5 |
| 384 | * payload is optional for 'RELEASE COMPLETE' message |
| 385 | */ |
| 386 | if (msg_type != GSM0480_MTYPE_RELEASE_COMPLETE) { |
| 387 | if (len < 2) { |
| 388 | LOGP(0, LOGL_DEBUG, "SS Request is too short.\n"); |
| 389 | return 0; |
| 390 | } |
| 391 | } |
| 392 | |
Vadim Yanitskiy | 44ebb93 | 2018-01-17 02:59:46 +0600 | [diff] [blame] | 393 | /* Table 2.1: Messages for call independent SS control */ |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 394 | switch (msg_type) { |
| 395 | case GSM0480_MTYPE_RELEASE_COMPLETE: |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 396 | LOGP(0, LOGL_DEBUG, "SS Release Complete\n"); |
Vadim Yanitskiy | 3cafc06 | 2018-01-17 12:28:40 +0600 | [diff] [blame] | 397 | |
Vadim Yanitskiy | fb5da89 | 2018-04-04 19:25:38 +0700 | [diff] [blame] | 398 | /** |
| 399 | * Indicates that there is no decoded message. |
| 400 | * To be overwriten by the message otherwise. |
| 401 | */ |
| 402 | req->ussd_text[0] = 0xFF; |
| 403 | |
Vadim Yanitskiy | 3cafc06 | 2018-01-17 12:28:40 +0600 | [diff] [blame] | 404 | /* Parse optional Cause and/or Facility data */ |
| 405 | if (len >= 2) |
| 406 | rc &= parse_ss_info_elements(&hdr->data[0], len, req); |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 407 | break; |
| 408 | case GSM0480_MTYPE_REGISTER: |
Vadim Yanitskiy | 7689e0f | 2018-01-17 03:23:39 +0600 | [diff] [blame] | 409 | rc &= parse_ss_info_elements(&hdr->data[0], len, req); |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 410 | break; |
Vadim Yanitskiy | c30431f | 2017-07-29 04:47:42 +0600 | [diff] [blame] | 411 | case GSM0480_MTYPE_FACILITY: |
Vadim Yanitskiy | 7689e0f | 2018-01-17 03:23:39 +0600 | [diff] [blame] | 412 | rc &= parse_ss_facility(&hdr->data[0], len, req); |
Vadim Yanitskiy | c30431f | 2017-07-29 04:47:42 +0600 | [diff] [blame] | 413 | break; |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 414 | default: |
| 415 | LOGP(0, LOGL_DEBUG, "Unknown GSM 04.80 message-type field 0x%02x\n", |
Holger Hans Peter Freyther | daa653f | 2010-10-11 07:56:06 +0200 | [diff] [blame] | 416 | hdr->msg_type); |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 417 | rc = 0; |
| 418 | break; |
| 419 | } |
| 420 | |
| 421 | return rc; |
| 422 | } |
| 423 | |
Vadim Yanitskiy | c30431f | 2017-07-29 04:47:42 +0600 | [diff] [blame] | 424 | static int parse_ss_facility(const uint8_t *ss_facility, uint16_t len, |
| 425 | struct ss_request *req) |
| 426 | { |
| 427 | uint8_t facility_length; |
| 428 | |
| 429 | facility_length = ss_facility[0]; |
| 430 | if (len - 1 < facility_length) |
| 431 | return 0; |
| 432 | |
Vadim Yanitskiy | 5a09f75 | 2018-06-11 04:58:53 +0700 | [diff] [blame] | 433 | return !gsm0480_parse_facility_ie(ss_facility + 1, facility_length, req); |
Vadim Yanitskiy | c30431f | 2017-07-29 04:47:42 +0600 | [diff] [blame] | 434 | } |
| 435 | |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 436 | static int parse_ss_info_elements(const uint8_t *ss_ie, uint16_t len, |
| 437 | struct ss_request *req) |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 438 | { |
| 439 | int rc = -1; |
| 440 | /* Information Element Identifier - table 3.2 & GSM 04.08 section 10.5 */ |
Holger Hans Peter Freyther | daa653f | 2010-10-11 07:56:06 +0200 | [diff] [blame] | 441 | uint8_t iei; |
| 442 | uint8_t iei_length; |
| 443 | |
Vadim Yanitskiy | b92a27f | 2018-01-17 12:18:27 +0600 | [diff] [blame] | 444 | /* We need at least two bytes */ |
| 445 | if (len < 2) |
| 446 | return 0; |
| 447 | |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 448 | iei = ss_ie[0]; |
| 449 | iei_length = ss_ie[1]; |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 450 | |
Holger Hans Peter Freyther | 8ac0486 | 2010-10-11 08:08:58 +0200 | [diff] [blame] | 451 | /* If the data does not fit, report an error */ |
Vadim Yanitskiy | b92a27f | 2018-01-17 12:18:27 +0600 | [diff] [blame] | 452 | if (iei_length + 2 > len) |
Holger Hans Peter Freyther | 8ac0486 | 2010-10-11 08:08:58 +0200 | [diff] [blame] | 453 | return 0; |
| 454 | |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 455 | switch (iei) { |
| 456 | case GSM48_IE_CAUSE: |
| 457 | break; |
| 458 | case GSM0480_IE_FACILITY: |
Vadim Yanitskiy | 5a09f75 | 2018-06-11 04:58:53 +0700 | [diff] [blame] | 459 | rc = !gsm0480_parse_facility_ie(ss_ie + 2, iei_length, req); |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 460 | break; |
| 461 | case GSM0480_IE_SS_VERSION: |
| 462 | break; |
| 463 | default: |
| 464 | LOGP(0, LOGL_DEBUG, "Unhandled GSM 04.08 or 04.80 IEI 0x%02x\n", |
| 465 | iei); |
| 466 | rc = 0; |
| 467 | break; |
| 468 | } |
| 469 | |
Vadim Yanitskiy | b92a27f | 2018-01-17 12:18:27 +0600 | [diff] [blame] | 470 | /* A message may contain multiple IEs */ |
| 471 | if (iei_length + 2 + 2 < len) |
| 472 | rc &= parse_ss_info_elements(ss_ie + iei_length + 2, |
| 473 | len - iei_length - 2, req); |
| 474 | |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 475 | return rc; |
| 476 | } |
| 477 | |
Vadim Yanitskiy | 5a09f75 | 2018-06-11 04:58:53 +0700 | [diff] [blame] | 478 | /*! Parse the components of a given Facility IE |
| 479 | * \param[in] facility_ie The Facility IE |
| 480 | * \param[in] length The length of Facility IE |
| 481 | * \param[out] req Abstract representation of SS message |
| 482 | * \return 0 in case of success, otherwise -ERRNO |
| 483 | */ |
| 484 | int gsm0480_parse_facility_ie(const uint8_t *facility_ie, uint16_t length, |
| 485 | struct ss_request *req) |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 486 | { |
Vadim Yanitskiy | 5a09f75 | 2018-06-11 04:58:53 +0700 | [diff] [blame] | 487 | uint8_t component_length; |
| 488 | uint8_t component_type; |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 489 | uint8_t offset = 0; |
Vadim Yanitskiy | 5a09f75 | 2018-06-11 04:58:53 +0700 | [diff] [blame] | 490 | int rc = 1; |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 491 | |
Vadim Yanitskiy | 5a09f75 | 2018-06-11 04:58:53 +0700 | [diff] [blame] | 492 | /* Iterate over components within IE */ |
Holger Hans Peter Freyther | 4156ec6 | 2010-10-11 09:07:50 +0200 | [diff] [blame] | 493 | while (offset + 2 <= length) { |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 494 | /* Component Type tag - table 3.7 */ |
Vadim Yanitskiy | 5a09f75 | 2018-06-11 04:58:53 +0700 | [diff] [blame] | 495 | component_type = facility_ie[offset]; |
| 496 | component_length = facility_ie[offset + 1]; |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 497 | |
Vadim Yanitskiy | 5a09f75 | 2018-06-11 04:58:53 +0700 | [diff] [blame] | 498 | /* Make sure that there is no overflow */ |
Holger Hans Peter Freyther | 4156ec6 | 2010-10-11 09:07:50 +0200 | [diff] [blame] | 499 | if (offset + 2 + component_length > length) { |
| 500 | LOGP(0, LOGL_ERROR, "Component does not fit.\n"); |
Vadim Yanitskiy | 5a09f75 | 2018-06-11 04:58:53 +0700 | [diff] [blame] | 501 | return -EINVAL; |
Holger Hans Peter Freyther | 4156ec6 | 2010-10-11 09:07:50 +0200 | [diff] [blame] | 502 | } |
| 503 | |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 504 | switch (component_type) { |
| 505 | case GSM0480_CTYPE_INVOKE: |
Vadim Yanitskiy | 5a09f75 | 2018-06-11 04:58:53 +0700 | [diff] [blame] | 506 | rc &= parse_ss_invoke(facility_ie + 2, |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 507 | component_length, |
| 508 | req); |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 509 | break; |
| 510 | case GSM0480_CTYPE_RETURN_RESULT: |
Vadim Yanitskiy | 5a09f75 | 2018-06-11 04:58:53 +0700 | [diff] [blame] | 511 | rc &= parse_ss_return_result(facility_ie + 2, |
Vadim Yanitskiy | 7f16c44 | 2017-07-29 05:05:54 +0600 | [diff] [blame] | 512 | component_length, |
| 513 | req); |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 514 | break; |
| 515 | case GSM0480_CTYPE_RETURN_ERROR: |
| 516 | break; |
| 517 | case GSM0480_CTYPE_REJECT: |
| 518 | break; |
| 519 | default: |
| 520 | LOGP(0, LOGL_DEBUG, "Unknown GSM 04.80 Facility " |
| 521 | "Component Type 0x%02x\n", component_type); |
| 522 | rc = 0; |
| 523 | break; |
| 524 | } |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 525 | |
Vadim Yanitskiy | 5a09f75 | 2018-06-11 04:58:53 +0700 | [diff] [blame] | 526 | offset += (component_length + 2); |
| 527 | } |
| 528 | |
| 529 | /** |
| 530 | * The internal functions are using inverted return |
| 531 | * codes, where '0' means error/failure. While a |
| 532 | * common approach is to return negative errno in |
| 533 | * case of any failure, and '0' if all is ok. |
| 534 | */ |
| 535 | return (rc == 0) ? -EINVAL : 0; |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 536 | } |
| 537 | |
| 538 | /* Parse an Invoke component - see table 3.3 */ |
Holger Hans Peter Freyther | 49ad500 | 2010-10-11 09:06:47 +0200 | [diff] [blame] | 539 | static int parse_ss_invoke(const uint8_t *invoke_data, uint16_t length, |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 540 | struct ss_request *req) |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 541 | { |
| 542 | int rc = 1; |
| 543 | uint8_t offset; |
| 544 | |
Holger Hans Peter Freyther | 7d0bce3 | 2010-10-11 09:12:33 +0200 | [diff] [blame] | 545 | if (length < 3) |
| 546 | return 0; |
| 547 | |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 548 | /* mandatory part */ |
| 549 | if (invoke_data[0] != GSM0480_COMPIDTAG_INVOKE_ID) { |
| 550 | LOGP(0, LOGL_DEBUG, "Unexpected GSM 04.80 Component-ID tag " |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 551 | "0x%02x (expecting Invoke ID tag)\n", invoke_data[0]); |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 552 | } |
| 553 | |
| 554 | offset = invoke_data[1] + 2; |
| 555 | req->invoke_id = invoke_data[2]; |
| 556 | |
Holger Hans Peter Freyther | 7d0bce3 | 2010-10-11 09:12:33 +0200 | [diff] [blame] | 557 | /* look ahead once */ |
| 558 | if (offset + 1 > length) |
| 559 | return 0; |
| 560 | |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 561 | /* optional part */ |
| 562 | if (invoke_data[offset] == GSM0480_COMPIDTAG_LINKED_ID) |
| 563 | offset += invoke_data[offset+1] + 2; /* skip over it */ |
| 564 | |
| 565 | /* mandatory part */ |
| 566 | if (invoke_data[offset] == GSM0480_OPERATION_CODE) { |
Holger Hans Peter Freyther | 7d0bce3 | 2010-10-11 09:12:33 +0200 | [diff] [blame] | 567 | if (offset + 2 > length) |
| 568 | return 0; |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 569 | uint8_t operation_code = invoke_data[offset+2]; |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 570 | req->opcode = operation_code; |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 571 | switch (operation_code) { |
Vadim Yanitskiy | 511426d | 2017-07-29 05:11:39 +0600 | [diff] [blame] | 572 | case GSM0480_OP_CODE_USS_NOTIFY: |
| 573 | case GSM0480_OP_CODE_USS_REQUEST: |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 574 | case GSM0480_OP_CODE_PROCESS_USS_REQ: |
| 575 | rc = parse_process_uss_req(invoke_data + offset + 3, |
| 576 | length - offset - 3, |
| 577 | req); |
| 578 | break; |
Vadim Yanitskiy | 394447b | 2017-07-29 05:14:15 +0600 | [diff] [blame] | 579 | case GSM0480_OP_CODE_PROCESS_USS_DATA: |
| 580 | rc = parse_process_uss_data(invoke_data + offset + 3, |
| 581 | length - offset - 3, |
| 582 | req); |
| 583 | break; |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 584 | case GSM0480_OP_CODE_ACTIVATE_SS: |
| 585 | case GSM0480_OP_CODE_DEACTIVATE_SS: |
| 586 | case GSM0480_OP_CODE_INTERROGATE_SS: |
| 587 | rc = parse_ss_for_bs_req(invoke_data + offset + 3, |
| 588 | length - offset - 3, |
| 589 | req); |
| 590 | break; |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 591 | default: |
| 592 | LOGP(0, LOGL_DEBUG, "GSM 04.80 operation code 0x%02x " |
| 593 | "is not yet handled\n", operation_code); |
| 594 | rc = 0; |
| 595 | break; |
| 596 | } |
| 597 | } else { |
| 598 | LOGP(0, LOGL_DEBUG, "Unexpected GSM 04.80 Component-ID tag 0x%02x " |
| 599 | "(expecting Operation Code tag)\n", |
| 600 | invoke_data[0]); |
| 601 | rc = 0; |
| 602 | } |
| 603 | |
| 604 | return rc; |
| 605 | } |
| 606 | |
Vadim Yanitskiy | 7f16c44 | 2017-07-29 05:05:54 +0600 | [diff] [blame] | 607 | /* Parse a Return Result component - see table 3.4 */ |
| 608 | static int parse_ss_return_result(const uint8_t *rr_data, uint16_t length, |
| 609 | struct ss_request *req) |
| 610 | { |
| 611 | uint8_t operation_code; |
| 612 | uint8_t offset; |
| 613 | |
| 614 | if (length < 3) |
| 615 | return 0; |
| 616 | |
| 617 | /* Mandatory part */ |
| 618 | if (rr_data[0] != GSM0480_COMPIDTAG_INVOKE_ID) { |
| 619 | LOGP(0, LOGL_DEBUG, "Unexpected GSM 04.80 Component-ID tag " |
| 620 | "0x%02x (expecting Invoke ID tag)\n", rr_data[0]); |
| 621 | return 0; |
| 622 | } |
| 623 | |
| 624 | offset = rr_data[1] + 2; |
| 625 | req->invoke_id = rr_data[2]; |
| 626 | |
| 627 | if (offset >= length) |
| 628 | return 0; |
| 629 | |
| 630 | if (rr_data[offset] != GSM_0480_SEQUENCE_TAG) |
| 631 | return 0; |
| 632 | |
| 633 | if (offset + 2 > length) |
| 634 | return 0; |
| 635 | |
| 636 | offset += 2; |
| 637 | operation_code = rr_data[offset + 2]; |
| 638 | req->opcode = operation_code; |
| 639 | |
| 640 | switch (operation_code) { |
| 641 | case GSM0480_OP_CODE_USS_NOTIFY: |
| 642 | case GSM0480_OP_CODE_USS_REQUEST: |
| 643 | case GSM0480_OP_CODE_PROCESS_USS_REQ: |
| 644 | return parse_process_uss_req(rr_data + offset + 3, |
| 645 | length - offset - 3, req); |
| 646 | case GSM0480_OP_CODE_PROCESS_USS_DATA: |
| 647 | return parse_process_uss_data(rr_data + offset + 3, |
| 648 | length - offset - 3, req); |
| 649 | default: |
| 650 | LOGP(0, LOGL_DEBUG, "GSM 04.80 operation code 0x%02x " |
| 651 | "is not yet handled\n", operation_code); |
| 652 | return 0; |
| 653 | } |
| 654 | |
| 655 | return 1; |
| 656 | } |
| 657 | |
| 658 | static int parse_process_uss_data(const uint8_t *uss_req_data, uint16_t length, |
| 659 | struct ss_request *req) |
| 660 | { |
| 661 | uint8_t num_chars; |
| 662 | |
| 663 | /* we need at least that much */ |
| 664 | if (length < 3) |
| 665 | return 0; |
| 666 | |
| 667 | if (uss_req_data[0] != ASN1_IA5_STRING_TAG) |
| 668 | return 0; |
| 669 | |
| 670 | num_chars = uss_req_data[1]; |
| 671 | if (num_chars > length - 2) |
| 672 | return 0; |
| 673 | |
Vadim Yanitskiy | 2ecfb30 | 2018-04-04 19:19:07 +0700 | [diff] [blame] | 674 | /* Drop messages with incorrect length */ |
| 675 | if (num_chars > GSM0480_USSD_OCTET_STRING_LEN) { |
| 676 | LOGP(DLGLOBAL, LOGL_ERROR, "Incorrect USS_DATA data length=%u, " |
| 677 | "dropping message", num_chars); |
| 678 | return 0; |
| 679 | } |
Vadim Yanitskiy | 7f16c44 | 2017-07-29 05:05:54 +0600 | [diff] [blame] | 680 | |
| 681 | memcpy(req->ussd_text, uss_req_data + 2, num_chars); |
| 682 | |
Vadim Yanitskiy | a24ead0 | 2018-04-04 10:34:41 +0700 | [diff] [blame] | 683 | /* Copy the data 'as is' */ |
| 684 | memcpy(req->ussd_data, uss_req_data + 2, num_chars); |
| 685 | req->ussd_data_len = num_chars; |
| 686 | req->ussd_data_dcs = 0x00; |
| 687 | |
Vadim Yanitskiy | 7f16c44 | 2017-07-29 05:05:54 +0600 | [diff] [blame] | 688 | return 1; |
| 689 | } |
| 690 | |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 691 | /* Parse the parameters of a Process UnstructuredSS Request */ |
Holger Hans Peter Freyther | 49ad500 | 2010-10-11 09:06:47 +0200 | [diff] [blame] | 692 | static int parse_process_uss_req(const uint8_t *uss_req_data, uint16_t length, |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 693 | struct ss_request *req) |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 694 | { |
Vadim Yanitskiy | 5b0790d | 2017-07-29 04:26:21 +0600 | [diff] [blame] | 695 | uint8_t num_chars; |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 696 | uint8_t dcs; |
| 697 | |
Holger Hans Peter Freyther | d65a698 | 2010-10-11 09:23:50 +0200 | [diff] [blame] | 698 | /* we need at least that much */ |
| 699 | if (length < 8) |
| 700 | return 0; |
| 701 | |
Vadim Yanitskiy | 5b0790d | 2017-07-29 04:26:21 +0600 | [diff] [blame] | 702 | if (uss_req_data[0] != GSM_0480_SEQUENCE_TAG) |
| 703 | return 0; |
Holger Hans Peter Freyther | d65a698 | 2010-10-11 09:23:50 +0200 | [diff] [blame] | 704 | |
Vadim Yanitskiy | 5b0790d | 2017-07-29 04:26:21 +0600 | [diff] [blame] | 705 | /* Both 2th and 5th should be equal to ASN1_OCTET_STRING_TAG */ |
| 706 | if ((uss_req_data[2] & uss_req_data[5]) != ASN1_OCTET_STRING_TAG) |
| 707 | return 0; |
| 708 | |
Vadim Yanitskiy | 01b8572 | 2017-07-29 04:43:48 +0600 | [diff] [blame] | 709 | /* Get DCS (Data Coding Scheme) */ |
Vadim Yanitskiy | 5b0790d | 2017-07-29 04:26:21 +0600 | [diff] [blame] | 710 | dcs = uss_req_data[4]; |
Vadim Yanitskiy | a24ead0 | 2018-04-04 10:34:41 +0700 | [diff] [blame] | 711 | /* Get the amount of bytes */ |
| 712 | num_chars = uss_req_data[6]; |
| 713 | |
Vadim Yanitskiy | 2ecfb30 | 2018-04-04 19:19:07 +0700 | [diff] [blame] | 714 | /* Drop messages with incorrect length */ |
| 715 | if (num_chars > GSM0480_USSD_OCTET_STRING_LEN) { |
| 716 | LOGP(DLGLOBAL, LOGL_ERROR, "Incorrect USS_REQ data length=%u, " |
| 717 | "dropping message", num_chars); |
| 718 | return 0; |
| 719 | } |
Vadim Yanitskiy | a24ead0 | 2018-04-04 10:34:41 +0700 | [diff] [blame] | 720 | |
| 721 | /* Copy the data 'as is' */ |
| 722 | memcpy(req->ussd_data, uss_req_data + 7, num_chars); |
| 723 | req->ussd_data_len = num_chars; |
| 724 | req->ussd_data_dcs = dcs; |
Vadim Yanitskiy | 01b8572 | 2017-07-29 04:43:48 +0600 | [diff] [blame] | 725 | |
| 726 | /** |
| 727 | * According to GSM 04.08, 4.4.2 "ASN.1 data types": |
| 728 | * the USSD-DataCodingScheme shall indicate use of |
| 729 | * the default alphabet using the 0x0F value. |
| 730 | */ |
Vadim Yanitskiy | 5b0790d | 2017-07-29 04:26:21 +0600 | [diff] [blame] | 731 | if (dcs == 0x0F) { |
Vadim Yanitskiy | 01b8572 | 2017-07-29 04:43:48 +0600 | [diff] [blame] | 732 | /* Calculate the amount of 7-bit characters */ |
Vadim Yanitskiy | a24ead0 | 2018-04-04 10:34:41 +0700 | [diff] [blame] | 733 | num_chars = (num_chars * 8) / 7; |
Vadim Yanitskiy | 01b8572 | 2017-07-29 04:43:48 +0600 | [diff] [blame] | 734 | |
Vadim Yanitskiy | 5b0790d | 2017-07-29 04:26:21 +0600 | [diff] [blame] | 735 | gsm_7bit_decode_n_ussd((char *)req->ussd_text, |
| 736 | sizeof(req->ussd_text), &(uss_req_data[7]), num_chars); |
| 737 | |
| 738 | return 1; |
Vadim Yanitskiy | 01b8572 | 2017-07-29 04:43:48 +0600 | [diff] [blame] | 739 | } else { |
Vadim Yanitskiy | 01b8572 | 2017-07-29 04:43:48 +0600 | [diff] [blame] | 740 | memcpy(req->ussd_text, &(uss_req_data[7]), num_chars); |
Vadim Yanitskiy | 01b8572 | 2017-07-29 04:43:48 +0600 | [diff] [blame] | 741 | return 1; |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 742 | } |
Vadim Yanitskiy | 5b0790d | 2017-07-29 04:26:21 +0600 | [diff] [blame] | 743 | |
| 744 | return 0; |
Holger Hans Peter Freyther | 00cb570 | 2010-10-09 01:47:15 +0800 | [diff] [blame] | 745 | } |
Holger Hans Peter Freyther | c64970e | 2010-10-18 16:56:43 +0200 | [diff] [blame] | 746 | |
Tobias Engel | 419684e | 2012-03-08 13:31:52 +0100 | [diff] [blame] | 747 | /* Parse the parameters of a Interrogate/Activate/DeactivateSS Request */ |
| 748 | static int parse_ss_for_bs_req(const uint8_t *ss_req_data, |
| 749 | uint16_t length, |
| 750 | struct ss_request *req) |
| 751 | { |
| 752 | int rc = 0; |
| 753 | |
| 754 | |
| 755 | /* we need at least that much */ |
| 756 | if (length < 5) |
| 757 | return 0; |
| 758 | |
| 759 | |
| 760 | if (ss_req_data[0] == GSM_0480_SEQUENCE_TAG) { |
| 761 | if ((ss_req_data[2] == ASN1_OCTET_STRING_TAG) && |
| 762 | ss_req_data[3] == 1) { |
| 763 | req->ss_code = ss_req_data[4]; |
| 764 | |
| 765 | rc = 1; |
| 766 | } |
| 767 | } |
| 768 | return rc; |
| 769 | } |
| 770 | |
Harald Welte | 88fa5a3 | 2018-07-28 22:55:43 +0200 | [diff] [blame] | 771 | struct msgb *gsm0480_msgb_alloc_name(const char *name) |
| 772 | { |
| 773 | return msgb_alloc_headroom(1024, 128, name); |
| 774 | } |
| 775 | |
Harald Welte | b0d9594 | 2018-07-28 23:02:48 +0200 | [diff] [blame] | 776 | /*! Generate a USSD ReturnResult component containing a string in default GSM alphabet. |
| 777 | * \param[in] invoke_id InvokeID of the request to which we respond |
| 778 | * \param[in] text USSD text in ASCII; to be encoded as GSM 7-but alphabet |
| 779 | */ |
| 780 | struct msgb *gsm0480_gen_ussd_resp_7bit(uint8_t invoke_id, const char *text) |
Holger Hans Peter Freyther | c64970e | 2010-10-18 16:56:43 +0200 | [diff] [blame] | 781 | { |
| 782 | struct msgb *msg; |
Holger Hans Peter Freyther | c64970e | 2010-10-18 16:56:43 +0200 | [diff] [blame] | 783 | uint8_t *ptr8; |
Holger Hans Peter Freyther | 47aa482 | 2013-07-07 13:54:53 +0200 | [diff] [blame] | 784 | int response_len; |
Holger Hans Peter Freyther | c64970e | 2010-10-18 16:56:43 +0200 | [diff] [blame] | 785 | |
Harald Welte | 88fa5a3 | 2018-07-28 22:55:43 +0200 | [diff] [blame] | 786 | msg = gsm0480_msgb_alloc_name("TS 04.80 USSD Resp"); |
Holger Hans Peter Freyther | c64970e | 2010-10-18 16:56:43 +0200 | [diff] [blame] | 787 | if (!msg) |
| 788 | return NULL; |
| 789 | |
| 790 | /* First put the payload text into the message */ |
| 791 | ptr8 = msgb_put(msg, 0); |
Jacob Erlbeck | 1d7f3b5 | 2013-08-12 17:07:53 +0200 | [diff] [blame] | 792 | gsm_7bit_encode_n_ussd(ptr8, msgb_tailroom(msg), text, &response_len); |
Holger Hans Peter Freyther | 47aa482 | 2013-07-07 13:54:53 +0200 | [diff] [blame] | 793 | msgb_put(msg, response_len); |
Holger Hans Peter Freyther | c64970e | 2010-10-18 16:56:43 +0200 | [diff] [blame] | 794 | |
| 795 | /* Then wrap it as an Octet String */ |
| 796 | msgb_wrap_with_TL(msg, ASN1_OCTET_STRING_TAG); |
| 797 | |
| 798 | /* Pre-pend the DCS octet string */ |
Max | 84fb5bb | 2018-11-08 13:23:59 +0100 | [diff] [blame] | 799 | msgb_tlv1_push(msg, ASN1_OCTET_STRING_TAG, 0x0F); |
Holger Hans Peter Freyther | c64970e | 2010-10-18 16:56:43 +0200 | [diff] [blame] | 800 | |
| 801 | /* Then wrap these as a Sequence */ |
| 802 | msgb_wrap_with_TL(msg, GSM_0480_SEQUENCE_TAG); |
| 803 | |
| 804 | /* Pre-pend the operation code */ |
Max | 84fb5bb | 2018-11-08 13:23:59 +0100 | [diff] [blame] | 805 | msgb_tlv1_push(msg, GSM0480_OPERATION_CODE, |
Holger Hans Peter Freyther | c64970e | 2010-10-18 16:56:43 +0200 | [diff] [blame] | 806 | GSM0480_OP_CODE_PROCESS_USS_REQ); |
| 807 | |
| 808 | /* Wrap the operation code and IA5 string as a sequence */ |
| 809 | msgb_wrap_with_TL(msg, GSM_0480_SEQUENCE_TAG); |
| 810 | |
| 811 | /* Pre-pend the invoke ID */ |
Max | 84fb5bb | 2018-11-08 13:23:59 +0100 | [diff] [blame] | 812 | msgb_tlv1_push(msg, GSM0480_COMPIDTAG_INVOKE_ID, invoke_id); |
Holger Hans Peter Freyther | c64970e | 2010-10-18 16:56:43 +0200 | [diff] [blame] | 813 | |
| 814 | /* Wrap this up as a Return Result component */ |
| 815 | msgb_wrap_with_TL(msg, GSM0480_CTYPE_RETURN_RESULT); |
| 816 | |
Harald Welte | b0d9594 | 2018-07-28 23:02:48 +0200 | [diff] [blame] | 817 | return msg; |
| 818 | } |
| 819 | |
| 820 | /*! Legacy helper: Generate USSD response including FACILITY IE + L3 header. |
| 821 | * |
| 822 | * This function is just like \ref gsm0480_gen_ussd_resp_7bit, but it generates |
| 823 | * not only the FACILITY value, but the full L3 message including message header |
| 824 | * and FACILITY IE Tag+Length. |
| 825 | */ |
| 826 | struct msgb *gsm0480_create_ussd_resp(uint8_t invoke_id, uint8_t trans_id, const char *text) |
| 827 | { |
| 828 | struct msgb *msg; |
| 829 | |
| 830 | msg = gsm0480_gen_ussd_resp_7bit(invoke_id, text); |
| 831 | if (!msg) |
| 832 | return NULL; |
| 833 | |
Holger Hans Peter Freyther | c64970e | 2010-10-18 16:56:43 +0200 | [diff] [blame] | 834 | /* Wrap the component in a Facility message */ |
| 835 | msgb_wrap_with_TL(msg, GSM0480_IE_FACILITY); |
| 836 | |
| 837 | /* And finally pre-pend the L3 header */ |
Vadim Yanitskiy | 30cfeeb | 2018-08-03 05:44:00 +0700 | [diff] [blame] | 838 | gsm48_push_l3hdr_tid(msg, GSM48_PDISC_NC_SS, |
| 839 | /* FIXME: TI direction is always 1 ?!? */ |
| 840 | trans_id | (1 << 7), |
| 841 | GSM0480_MTYPE_RELEASE_COMPLETE); |
| 842 | |
Holger Hans Peter Freyther | c64970e | 2010-10-18 16:56:43 +0200 | [diff] [blame] | 843 | return msg; |
| 844 | } |
Neels Hofmeyr | 25774b9 | 2016-11-26 15:21:05 +0100 | [diff] [blame] | 845 | |
Harald Welte | 7ecc4a3 | 2018-07-28 23:05:36 +0200 | [diff] [blame] | 846 | /*! Generate a ReturnError component (see section 3.6.1) and given error code (see section 3.6.6). |
| 847 | * \param[in] invoke_id InvokeID of the request |
| 848 | * \param[in] error_code Error code (section 4.5) |
| 849 | * \return message buffer containing the Reject component |
Harald Welte | 7ecc4a3 | 2018-07-28 23:05:36 +0200 | [diff] [blame] | 850 | */ |
| 851 | struct msgb *gsm0480_gen_return_error(uint8_t invoke_id, uint8_t error_code) |
| 852 | { |
Vadim Yanitskiy | 3fc4616 | 2018-08-03 03:45:06 +0700 | [diff] [blame] | 853 | struct msgb *msg; |
| 854 | |
| 855 | msg = gsm0480_msgb_alloc_name("TS 04.80 ReturnError"); |
| 856 | if (!msg) |
| 857 | return NULL; |
Harald Welte | 7ecc4a3 | 2018-07-28 23:05:36 +0200 | [diff] [blame] | 858 | |
| 859 | /* First insert the problem code */ |
Max | 84fb5bb | 2018-11-08 13:23:59 +0100 | [diff] [blame] | 860 | msgb_tlv1_push(msg, GSM_0480_ERROR_CODE_TAG, error_code); |
Harald Welte | 7ecc4a3 | 2018-07-28 23:05:36 +0200 | [diff] [blame] | 861 | |
| 862 | /* Before it, insert the invoke ID */ |
Max | 84fb5bb | 2018-11-08 13:23:59 +0100 | [diff] [blame] | 863 | msgb_tlv1_push(msg, GSM0480_COMPIDTAG_INVOKE_ID, invoke_id); |
Harald Welte | 7ecc4a3 | 2018-07-28 23:05:36 +0200 | [diff] [blame] | 864 | |
| 865 | /* Wrap this up as a Reject component */ |
| 866 | msgb_wrap_with_TL(msg, GSM0480_CTYPE_RETURN_ERROR); |
| 867 | |
| 868 | /* FIXME: Wrap in Facility + L3? */ |
| 869 | return msg; |
| 870 | } |
| 871 | |
| 872 | /*! Generate a Reject component (see section 3.6.1) and given error code (see section 3.6.7). |
| 873 | * \param[in] invoke_id InvokeID of the request |
| 874 | * \param[in] problem_tag Problem code tag (table 3.13) |
| 875 | * \param[in] problem_code Problem code (table 3.14-3.17) |
| 876 | * \return message buffer containing the Reject component |
| 877 | * |
| 878 | * Note: if InvokeID is not available, e.g. when message parsing failed, any incorrect vlue |
| 879 | * can be passed (0x00 > x > 0xff), so the universal NULL-tag (see table 3.6) will be used instead. |
| 880 | */ |
| 881 | struct msgb *gsm0480_gen_reject(int invoke_id, uint8_t problem_tag, uint8_t problem_code) |
| 882 | { |
Vadim Yanitskiy | 3fc4616 | 2018-08-03 03:45:06 +0700 | [diff] [blame] | 883 | struct msgb *msg; |
| 884 | |
| 885 | msg = gsm0480_msgb_alloc_name("TS 04.80 Reject"); |
| 886 | if (!msg) |
| 887 | return NULL; |
Harald Welte | 7ecc4a3 | 2018-07-28 23:05:36 +0200 | [diff] [blame] | 888 | |
| 889 | /* First insert the problem code */ |
Max | 84fb5bb | 2018-11-08 13:23:59 +0100 | [diff] [blame] | 890 | msgb_tlv1_push(msg, problem_tag, problem_code); |
Harald Welte | 7ecc4a3 | 2018-07-28 23:05:36 +0200 | [diff] [blame] | 891 | |
| 892 | /* If the Invoke ID is not available, Universal NULL (table 3.9) with length=0 shall be used */ |
| 893 | if (invoke_id < 0 || invoke_id > 255) |
Max | 84fb5bb | 2018-11-08 13:23:59 +0100 | [diff] [blame] | 894 | msgb_tv_push(msg, ASN1_NULL_TYPE_TAG, 0); |
Harald Welte | 7ecc4a3 | 2018-07-28 23:05:36 +0200 | [diff] [blame] | 895 | else |
Max | 84fb5bb | 2018-11-08 13:23:59 +0100 | [diff] [blame] | 896 | msgb_tlv1_push(msg, GSM0480_COMPIDTAG_INVOKE_ID, invoke_id); |
Harald Welte | 7ecc4a3 | 2018-07-28 23:05:36 +0200 | [diff] [blame] | 897 | |
| 898 | /* Wrap this up as a Reject component */ |
| 899 | msgb_wrap_with_TL(msg, GSM0480_CTYPE_REJECT); |
| 900 | |
| 901 | /* FIXME: Wrap in Facility + L3? */ |
| 902 | return msg; |
| 903 | } |
| 904 | |
Neels Hofmeyr | bc1d758 | 2016-11-26 15:21:15 +0100 | [diff] [blame] | 905 | struct msgb *gsm0480_create_ussd_notify(int level, const char *text) |
| 906 | { |
| 907 | struct msgb *msg; |
| 908 | |
| 909 | msg = gsm0480_create_unstructuredSS_Notify(level, text); |
| 910 | if (!msg) |
| 911 | return NULL; |
| 912 | |
| 913 | gsm0480_wrap_invoke(msg, GSM0480_OP_CODE_USS_NOTIFY, 0); |
| 914 | gsm0480_wrap_facility(msg); |
| 915 | |
Vadim Yanitskiy | 30cfeeb | 2018-08-03 05:44:00 +0700 | [diff] [blame] | 916 | /* And finally pre-pend the L3 header */ |
| 917 | gsm48_push_l3hdr(msg, GSM48_PDISC_NC_SS, |
| 918 | /* FIXME: no transactionID?!? */ |
| 919 | GSM0480_MTYPE_REGISTER); |
| 920 | |
Neels Hofmeyr | bc1d758 | 2016-11-26 15:21:15 +0100 | [diff] [blame] | 921 | return msg; |
| 922 | } |
| 923 | |
| 924 | struct msgb *gsm0480_create_ussd_release_complete(void) |
| 925 | { |
| 926 | struct msgb *msg; |
| 927 | |
Vadim Yanitskiy | 39a36d0 | 2018-08-03 03:52:16 +0700 | [diff] [blame] | 928 | msg = gsm0480_msgb_alloc_name("TS 04.80 USSD REL COMPL"); |
Neels Hofmeyr | bc1d758 | 2016-11-26 15:21:15 +0100 | [diff] [blame] | 929 | if (!msg) |
| 930 | return NULL; |
| 931 | |
Vadim Yanitskiy | 30cfeeb | 2018-08-03 05:44:00 +0700 | [diff] [blame] | 932 | /* And finally pre-pend the L3 header */ |
| 933 | gsm48_push_l3hdr(msg, GSM48_PDISC_NC_SS, |
| 934 | /* FIXME: no transactionID?!? */ |
| 935 | GSM0480_MTYPE_RELEASE_COMPLETE); |
| 936 | |
Neels Hofmeyr | bc1d758 | 2016-11-26 15:21:15 +0100 | [diff] [blame] | 937 | return msg; |
| 938 | } |