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* add osmo_hexdump_buf() and testNeels Hofmeyr2019-01-281-0/+3
| | | | | | | | | | | | | | | | | | Add osmo_hexdump_buf() as an all-purpose hexdump function, which all other osmo_hexdump_*() implementations now call. It absorbs the static _osmo_hexdump(). Add tests for osmo_hexdump_buf(). Rationale: recently during patch review, a situation came up where two hexdumps in a single printf would have been useful. Now I've faced a similar situation again, in ongoing development. So I decided it is time to provide this API. The traditional osmo_hexdump() API returns a non-const char*, which should probably have been a const instead. Particularly this new function may return a string constant "" if the buf is NULL or empty, so return const char*. That is why the older implementations calling osmo_hexdump_buf() separately return the buffer instead of the const return value directly. Change-Id: I590595567b218b24e53c9eb1fd8736c0324d371d
* gsm0808: add BSSMAP Cell Identifier matching APINeels Hofmeyr2019-01-282-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | Add * osmo_lai_cmp() (to use in gsm0808_cell_id_u_matches()) * osmo_cgi_cmp() (to use in gsm0808_cell_id_u_matches()) * gsm0808_cell_id_u_match() (to re-use for single IDs and lists) * gsm0808_cell_ids_match() * gsm0808_cell_id_matches_list() * Unit tests in gsm0808_test.c Rationale: For inter-BSC handover, it is interesting to find matches between *differing* Cell Identity kinds. For example, if a cell as CGI 23-42-3-5, and a HO for LAC-CI 3-5 should be handled, we need to see the match. This is most interesting for osmo-msc, i.e. to direct the BSSMAP Handover Request towards the correct BSC or MSC. It is also interesting for osmo-bsc's VTY interface, to be able to manage cells' neighbors and to trigger manual handovers by various Cell Identity handles, as the user would expect them. Change-Id: I5535f0d149c2173294538df75764dd181b023312
* constrain gsm48_generate_mid() output array boundsHarald Welte2019-01-221-0/+1
| | | | | | | | | | | The longest BCd-digit type identity is the IMEISV with 16, so there's no point in trying to parse up to 255 decimal digits, which will do nothing but to overflow the caller-provided output buffer. Let's also clearly define the required minimum size of the output buffer and add a reltead #define for it. Change-Id: Ic8488bc7f77dc9182e372741b88f0f06100dddc9
* gsm_23_003.h: add GSM23003_IMEI_NUM_DIGITS_NO_CHKOliver Smith2019-01-211-0/+3
| | | | | | | Add new define for the 14 digit IMEI without the Luhn checksum, as it is used in OsmoHLR. Change-Id: I02b54cf01a674a1911c5c897fbec02240f88b521
* Rename msgb_wrap_with_TL()Max2019-01-211-1/+1
| | | | | | | | | | | | | | | This resolves an issue introduced in 84fb5bb6a09a6a358f98c654c84c3b99a0f24eef when msgb_wrap_with_TL() was introduced as an inline function with *exactly the same name* as in osmo-msc.git and openbsc.git. We *NEVER* do something like this. Functions moved from applications to library *MUST* always be renamed. This has been the case for almost a decade now. With this subsequent change we make sure the libosmocore function has a different name and doesn't clash. After this commit, old openbsc.git and osmo-bsc.git should again build fine. Change-Id: If1e851ac605c8d2fde3da565b0bd674ea6350c2e
* Prevent GCR encoder/decoder functions from being used directlyMax2019-01-191-2/+2
| | | | | | | | They only make sense in the context of LCLS so far - let's make sure they're not used by external projects directly instead of gsm0808_*() counterparts. Change-Id: I4ae5a3472a20492d5f76170b722e4e2274a5c433
* LCLS: make GCR into static member of osmo_lclsMax2019-01-191-1/+2
| | | | | | | | | Most of the time we'll have GCR filled anyway so it make sense to have it as static parameter instead of a pointer to separately allocated structure. Update tests to cover both static and dynamic osmo_lcls allocation variants. Change-Id: I905c36d8455911c68c30bc429379b7313dd46aea
* LCLS: add status parameter to Assignment Completed messageMax2019-01-191-0/+6
| | | | | | | | | | * add gsm0808_create_ass_compl2() with additional gsm0808_lcls_status parameter and make gsm0808_create_ass_compl() into trivial wrapper around it * update tests accordingly Change-Id: I547c6b8707123aa8c1ef636db88908df112d90a4 Related: OS#2487
* socket: add define for socket name lengthPhilipp Maier2019-01-171-0/+2
| | | | | | | | | | | The function osmo_sock_get_name_buf() can be used to write a string representation to a user provided memory. Unfortunately the proper length for the user provided memory is not obvious. To make using osmo_sock_get_name_buf() more practical, add a define constant that defines the length of the required memory. Also use this define in socket.c. Change-Id: If8be8c2c0d4935da17ab13b2c2127b719ceefbcc
* LCLS: add GCR comparison helperMax2019-01-141-0/+1
| | | | Change-Id: I9e3b5560a058b976638d03cb819415d237ae9984
* comments: update/fix three 3GPP spec referencesNeels Hofmeyr2019-01-143-3/+3
| | | | Change-Id: I3ab94f362866d752099000afe62922288b3dd118
* change GSM48_CMSERV_* to enum type, add namesNeels Hofmeyr2019-01-141-7/+14
| | | | | | | Prepare handling multiple CM Service Requests in osmo-msc: an enum is more clear than an int and #defines for passing around and count CM Service types. Change-Id: I9c2a7adc45ab7a1a7519168e965e7d805e1481ff
* gsm23003: add osmo_imei_str_valid()Oliver Smith2019-01-142-0/+3
| | | | | | | | | | | Verify 14 digit and 15 digit IMEI strings. OsmoHLR will use the 14 digit version to check IMEIs before writing them to the DB. Place the Luhn checksum code in a dedicated osmo_luhn() function, so it can be used elsewhere. Related: OS#2541 Change-Id: Id2d2a3a93b033bafc74c62e15297034bf4aafe61
* port rest octets encoding code from osmo-bscStefan Sperling2019-01-122-0/+126
| | | | | | | | | | | | | | | | | | | | | | | | | | As part of fixing issue OS#3075, we want to migrate support for encoding system information from osmo-bsc to libosmocore. This change ports osmo-bsc code for encoding SI rest octets. The conversion was a bit tricky in some places because some functions receive a 'struct gsm_bts' parameter in osmo-bsc. In this libosmocore version, such functions expect parameters which correspond to the individual fields of 'struct gsm_bts' which are used by these functions. Several structs from osmo-bsc's system_information.h are now also declared in libosmocore headers, with an added osmo_ prefix to avoid collisions with existing definitions in osmo-bsc. Some helpers were ported from osmo-bsc's system_information.c to libosmocore's gsm48_rest_octets.c. Contrary to osmo-bsc's implementation they are now only visible within this file. Unfortunately, this code ported from osmo-bsc lacks unit tests. Change-Id: I47888965ab11bba1186c21987f1365c9270abeab Related: OS#3075
* port arfcn range encode support from osmo-bscStefan Sperling2019-01-121-0/+25
| | | | | | | | | | | | | | As part of fixing issue OS#3075, we want to migrate support for encoding system information from osmo-bsc to libosmocore. This change ports one of the prerequisites for doing so: osmo-bsc code for range-encoding ARFCNs, including tests. An osmo_gsm48_ prefix has been prepended to public symbols in order to avoid clashes with existing symbols in osmo-bsc code. Change-Id: Ia220764fba451be5e975ae7c5eefb1a25ac2bf2c Related: OS#3075
* LCLS: use proper types for value_string wrappersMax2019-01-091-3/+3
| | | | Change-Id: I0f47a610e06ac99bd60a5aad6f50f3658480165e
* Cosmetic: GSUP: note "on wire" for imei_resultOliver Smith2019-01-091-2/+2
| | | | | | | | | | | | | | Note that OSMO_GSUP_IMEI_RESULT_ACK is 0 on the wire, although the enum value is 1. Same with NACK (1 on wire, enum 2). I had implemented enum osmo_gsup_imei_result after enum osmo_gsup_cancel_type above, where this comment exists as well, and I incorrectly assumed that enum osmo_gsup_cn_domain in the middle was also implemented this way and therefore adding the comments to each enum would be redundant. But for cn_domain, the values on the wire are the same as the enum values. Change-Id: If97c34f117bfaab2232bbb625e9d118c8f390e58
* add osmo_lu_type_names[], osmo_lu_type_name()Neels Hofmeyr2019-01-081-0/+4
| | | | | | Move lupd_names[] from osmo-msc to libosmo-gsm. Change-Id: Ica25919758ef6cba8348da199b0ae7e0ba628798
* add osmo_mi_name(), for MI-to-string like "IMSI-123456"Neels Hofmeyr2019-01-081-0/+1
| | | | | | | | We have gsm48_mi_to_string() and osmo_bcd2str(), but still lack a function that conveniently prints both MI type and value in one function call. Related: http://people.osmocom.org/neels/mi_mi_mi.jpg Change-Id: I7798c3ef983c2e333b2b9cbffef6f366f370bd81
* LCLS: fix LCLS-CONNECT-CONTROL encoderMax2019-01-071-2/+2
| | | | | | | | | | | Previously it could encode both incorrect values as well as incorrect message. Let's fix this by explicitly checking for invalid values and ensuring that at least one of the parameters is valid. This function have no external or internal users so it's better to fix type signature as well to match the rest of gsm0808_create_lcls_*(). Change-Id: I7b33a771acbd391c5f9a494d6450edb18511433f
* fix typo in enum BSS_MAP_MSG_TYPE: BSS_MAP_MSG_ASSIGMENT*Neels Hofmeyr2019-01-041-3/+7
| | | | | | Keep #defines to still support previous wrong spelling. Change-Id: Id4cf812f0bc3cd40f6bfa05166f817a07a647f71
* osmo_rat_type: add OSMO_RAT_EUTRAN_SGSNeels Hofmeyr2019-01-041-0/+1
| | | | | | | osmo-msc is about to implement the SGs interface and requires a RAT indicator for that. Change-Id: I00588396bfe03feba38ecb0717d584594f0b2b46
* gsm_utils: add enum osmo_rat_type, from osmo-msc enum ran_typeNeels Hofmeyr2019-01-031-0/+13
| | | | | | | | | | | | | | | In the MSC, we have RAN types GERAN_A and UTRAN_IU, now we need a similar enum in osmo-hlr's GSUP client. Naming: in the MAP specifications, the RAN type is mostly called RAT type, (Radio Access Network vs. Radio Access Technology?). Since GSUP is more about MAP messages, I'm calling the enum osmo_rat_type. Rationale: osmo-msc and osmo-sgsn want to tell the osmo-hlr which RAT a subscriber is calling on. A subsequent patch will extend the GSUP protocol and add a RAT types IE. Change-Id: I659687aef7a4d67ca372a39fef31dee07aed7631
* add LOGPFSMSL(), LOGPFSMSLSRC()Neels Hofmeyr2019-01-031-6/+30
| | | | | | | | | | | | | | | | | | Using an FSM instace's logging context is very useful. Sometimes it makes sense to log something on a different logging category than the FSM definition's default category. For example, an MSC conn has aspects concerning MM, CC, RR, MGCP, ..., and currently all of those log on DMM. This came up in I358cfbaf0f44f25148e8b9bafcb9257b1952b35a, where I want to log an MGCP event using a ran_conn context, and used the conn->fi->id. That of course omits context like the current conn FSM state... I remember at least one other place where I recently added logging using some fi->id as context, so it might turn out useful in various places. Change-Id: I11b182a03f5ecb6df7cd8f260757d3626c8e945d
* LOGPFSM*: guard against fi == NULLNeels Hofmeyr2019-01-031-4/+4
| | | | | | | | The LOGPFSM macros are in such wide use that they should guard against a NULL fi pointer. In case of NULL, default to subsys = DLGLOBAL, loglevel = LOGL_ERROR and state = "fi=NULL". Change-Id: I9eaf8b7e2cf1e450ae626cb2fc928862008f6233
* add API doc for LOGPFSM* macrosNeels Hofmeyr2019-01-031-0/+31
| | | | Change-Id: I3bf6500889aa58195f50a726dec0876c0c2baec3
* LCLS: enc/dec entire parameter set instead of GCRMax2018-12-231-2/+2
| | | | | | | | | | | | | In 3GPP TS 48.008 the Global Call Reference IE is only used in HANDOVER REQUEST (§3.2.1.8) and ASSIGNMENT REQUEST (§3.2.1.1) messages which also include LCLS Config and CSC parameters. Hence, there's no point in using GCR encode/decode functions alone. Introduce gsm0808_dec_lcls() and gsm0808_enc_lcls() as trivial wrappers on top of GCR enc/dec routines which are made static. Adjust tests accordingly. Test output intentionally left unchanged. Change-Id: Icfbb2404e1a1d500243e2071173299b557369335
* define LOGPFSM fmt only once, in LOGPFSMLSRCNeels Hofmeyr2018-12-231-7/+4
| | | | | | | | | Instead of duplicating the fmt and args in LOGPFSML and LOGPFSMLSRC, rather make LOGPFSML invoke LOGPFSMLSRC with __FILE__ and __LINE__. This is a cosmetic preparation for more tweaks coming up. Change-Id: I2f23c57ebfdb5355919c06ac5ded7732e3b17a97
* vty: Make TCP port configurable and introduce telnet_init_defaultHolger Hans Peter Freyther2018-12-232-0/+3
| | | | | | | | | | | | | | | Extend the vty_bind_cmd VTY command to allow to optionally specify a port in addition to the IPv4 address. Introduce telnet_init_default to relieve client code from having to query the bind IPv4 address (and now the TCP port). Instead a client only needs to pass the default TCP port to use. Client code should use it like: int rc = telnet_init_default(ctx, priv, OSMO_VTY_PORT_SGSN); Change-Id: Id5fb2faaf4311bd7284ee870526a6f87b7e260f3
* GSUP: add CHECK-IMEI messageOliver Smith2018-12-211-0/+16
| | | | | | | | | | | | | | Implement necessary messages for Procedure Check_IMEI_VLR (TS 23.018 Chapter 7.1.2.9). This lets the VLR ask the EIR to check if an IMEI is valid. In the Osmocom stack, we don't have an EIR and this request will be handled by the HLR. We will be able to store the IMEI in the HLR as side-effect (OS#2541). This is roughly based on TS 29.002 8.7.1 MAP_CHECK_IMEI service, but only implements the bare minimum required IEs (imei and imei_result). Related: OS#3733 Change-Id: I085819df0ea7f3bfeb0cabebb5fd1942a23c6155
* GSUP: add end marker to enum osmo_gsup_ieiOliver Smith2018-12-211-0/+2
| | | | | | | | | | | | | Simplify gsup_test.c by defining an end marker in gsup.h. No need to manually update the last element every time anymore. The C standard guarantees, that the end marker will have the last value plus one: "Each subsequent enumerator with no = defines its enumeration constant as the value of the constant expression obtained by adding 1 to the value of the previous enumeration constant." (From C99: 6.7.2.2 Enumeration specifiers) Change-Id: I2aab7245e209f0ebd2f33a83d4d181dd3339cb17
* TLV: add convenience function for 1-byte valuesMax2018-12-201-0/+16
| | | | | | | Similar to existing 16 and 32 bit value helpers but simpler because we don't have to worry about alingment and endianness. Change-Id: Ic0a148bd04b8860e321f509fdcd913f688c8e920
* TLV: fix doc copy-paste errorMax2018-12-201-1/+1
| | | | Change-Id: I8aa79cab7505585de00ee2aaae125462108906e8
* Use define for key buffersMax2018-12-201-3/+3
| | | | | | Add corresponding spec. references and comments where appropriate. Change-Id: If5e2aad86eaecd8eada667b3488ba415d81c6312
* rename CELL_IDENT_LAI_AND_LAC to CELL_IDENT_LAIStefan Sperling2018-12-191-2/+3
| | | | | | | | | The name "LAI AND LAC" makes no sense because a LAC is part of a LAI. Keep the old name available for API backwards compatibility. Change-Id: I2749cf75b7b45de0cd43cf4c696a6b6984f5a065 Related: OS#3124
* add/clean big-endian packed structs (struct_endianess.py)Neels Hofmeyr2018-12-198-45/+646
| | | | | | | | | | | | | | This is 1:1 the result of doing cd libosmocore ./contrib/struct_endianess.py git commit -a Running struct_endianess.py again should result in no changes. That means we could include such a check in the gerrit verification job now. Change-Id: Ia0b99d76932aeb03e93bd0c62d3bf025dec5f9d2
* add to osmo_sock_get_name*() APINeels Hofmeyr2018-12-191-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Basically, I am applying code review that I would have given had I not been on vacation when the last osmo_sock_get_name* stuff was merged. osmo_sock_get_name2() is so far a static internal function. However, it is nothing like osmo_sock_get_name(), so instead rename it to osmo_sock_get_ip_and_port(). Also make it public API, no need to hide it. I'm adding an "and" in the name to hopefully clarify: "ip_port" vs. "ip_and_port" -- there already are _get_X_ip_port() functions that only return the port string, despite "ip" in the name. Add new public osmo_sock_get_name2(), which is like osmo_sock_get_name(), except it uses a static string instead of talloc, and omits the braces. This is most convenient for log statement formats, avoiding dyn allocations. Add new osmo_sock_get_name_buf(), which is like osmo_sock_get_name2() but writes to a caller provided char buffer. Use osmo_sock_get_name_buf() in the implementation of osmo_sock_get_name(), but use another (non-static) local string buffer, because adding braces is too complex without talloc_snprintf(). Rationale: I want to improve the logging of socket errors, e.g. change DLMGCP ERROR Failed to read: 111/Connection refused (mgcp_client.c:720) to DLMGCP ERROR Failed to read: r=10.0.99.2:2427<->l=10.0.99.2:2728: 111='Connection refused' (mgcp_client.c:721) but it is just not handy to compose logging with the current API: - osmo_sock_get_name() requires a talloc_free(). - all the others require output buffers. - the only way to conveniently compose a logging string and, - notably, the only trivial way to skip the string composition if the logging level is currently muted, is to have a function that returns a static string: the new osmo_sock_get_name2(). - (I think the osmo_sock_get_{local,remote}_* convenience wrappers should never have been added, because they encourage the caller to invoke the same code twice, for IP addr and port, and throw away one half each time.) Related: Iae728192f499330d16836d9435648f6b8ed213b6 (osmo-mgw) Change-Id: I8ad89ac447c9c582742e70d082072bdd40a5a398
* GSUP/SMS: introduce READY-FOR-SM messageVadim Yanitskiy2018-12-182-0/+14
| | | | | | | | | | | | | | | According to 3GPP TS 29.002, section 12.4, MAP-READY-FOR-SM is used between the MSC and VLR as well as between the VLR and the HLR to indicate that a subscriber has memory available for SMS. This change replicates this service in GSUP as READY_FOR_SM_*. The only mandatory IE for this service (excluding Invoke ID) is 'Alert Reason' that is replicated by OSMO_GSUP_SM_ALERT_RSN_IE. Change-Id: Ic37f3b2114b8095cfce22977e67133b9103942e3 Related Change-Id: (docs) I549b6c8840a1e86caac09e77fb8bc5042d939e62 Related Change-Id: (TTCN) If2256607527ecfcb10285583332fb8b0515d7c78 Related: OS#3587
* GSUP/SMS: introduce MO-/MT-FORWARD-SM messagesVadim Yanitskiy2018-12-182-0/+75
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | According to 3GPP TS 29.002, there are two services: - MAP-MO-FORWARD-SHORT-MESSAGE (see 12.2), - MAP-MT-FORWARD-SHORT-MESSAGE (see 12.9), which are used to forward MO/MT short messages. This change replicates both services as GSUP messages: - OSMO_GSUP_MSGT_MO_FORWARD_SM_*, - OSMO_GSUP_MSGT_MT_FORWARD_SM_*. Please note, that only the 'must-have' IEs are introduced by this change, in particular the following: - OSMO_GSUP_SM_RP_MR_IE (see note below), - OSMO_GSUP_SM_RP_DA_IE (see 7.6.8.1), - OSMO_GSUP_SM_RP_OA_IE (see 7.6.8.2), - OSMO_GSUP_SM_RP_UI_IE (see 7.6.8.4), - OSMO_GSUP_SM_RP_MMS_IE (see 7.6.8.7), - OSMO_GSUP_SM_RP_CAUSE_IE (see GSM TS 04.11, 8.2.5.4), where both SM_RP_DA and SM_RP_OA IEs basically contain a single nested TV of the following format: - T: identity type (see 'osmo_gsup_sms_sm_rp_oda_t'), - V: encoded identity itself (optional). According to GSM TS 04.11, every single message on the SM-RL has an unique message reference (see 8.2.3), that is used to link an RP-ACK or RP-ERROR message to the associated (preceding) RP-DATA or RP-SMMA message transfer attempt. In case of TCAP/MAP, this message reference is being mapped to the Invoke ID. But since GSUP has no 'Invoke ID' IE, and it is not required for other applications (other than SMS), this change introduces a special 'SM_RP_MR' IE that doesn't exist in MAP. Change-Id: Ibe325c64ae2d6c626b232533bb4cbc65fc2b5d71 Related Change-Id: (docs) Ie0150756c33c1352bc4eb49421824542c711175c Related Change-Id: (TTCN) Ibf49474a81235096c032ea21f217170f523bd94e Related: OS#3587
* LCLS: add gsm0808_create_ass2()Max2018-12-141-0/+6
| | | | | | | It allows setting additional assignment parameters explicitly. Change-Id: Id89765df3f8c12f55f73f1d7a9d90c8883eb3bba Related: OS#2487
* LCLS, TS 48.008: add GCR IE encoding/decodingMax2018-12-141-0/+5
| | | | | | | | * add functions to encode Global Call. Ref. from TS 29.205 as 3GPP TS 48.008 §3.2.2.115 information element * add corresponding tests Change-Id: I82ce0207dc8de50689a8806c6471ad7fbae6219d
* LCLS, TS 29.205: add GCR routinesMax2018-12-142-1/+42
| | | | | | | | Add functions to encode and decode Global Call Reference as per 3GPP TS 29.205 Table B 2.1.9.1 add corresponding tests. Change-Id: Iee95aa4e5c056645b6cb5667e4a067097d52dfbf Related: OS#2487
* stats.h: Fix build on MacOSPau Espin Pedrol2018-12-131-2/+2
| | | | | | | Otherwise struct osmo_stats_config is not defined and compiler fails. Related: OS#3722 Change-Id: I037c3ca141ecee2d457e0a881a56e32ee24cec4d
* msgb: add test helpersMax2018-12-121-0/+139
| | | | | | | | It's often handy to compare certain msgb layer to a given array and print the position where they differ. Add simple pretty-printer and corresponding L* wrappers. Change-Id: I3bc95f2f5ab6e3f4b502647fb3e0aaaf1f7c4cf5
* add osmo_bcd2str()Neels Hofmeyr2018-12-101-0/+2
| | | | | | | | | | | | | | | | | | Add a standalone bcd-to-string conversion function with generic parameters. Add a regression test in utils_test.c. So far there is no single universal implementation that converts a BCD to a string. I could only find gsm48_mi_to_string(), which also interprets surrounding bytes, MI type and TMSI as non-BCD value. The idea is to use this function from gsm48_mi_to_string() and similar implementations in subsequent commits. Root cause: in osmo-msc, I want to have an alternative MI-to-string function for composing an FSM name, which needs the BCD part of gsm48_mi_to_string() but not the TMSI part. Change-Id: I86b09d37ceef33331c1a56046a5443127d6c6be0
* Constify llist_count() parameterMax2018-12-101-1/+1
| | | | | | | Counting list entires should not alter the list content: let's make this obvious from type signature. Change-Id: I414e67a3de733fab407161b3264d3b89070ba537
* timer: Fix clockid_t undefined on MacOS < 10.12Pau Espin Pedrol2018-12-102-0/+5
| | | | | Related: OS#3722 Change-Id: If466a64bd44dcb8ae8a9b7f82bc9c9435ba3e640
* gsm0808: add encoder for cause codes and use itPhilipp Maier2018-12-081-0/+1
| | | | | | | | | | | | | | | | At the moment the all gsm0808 cause codes are encoded directly using the tlv API directly to put a one byte TLV field. This works ok for most situations where the cause code consists of a single byte. However, gsm0808 specifies a two byte cause code model where cause codes may be extended up to two bytes. Instead of implementing the encoding over and over and again, let's rather have an encoder function we can call. - Add an encoder function that can generate single byte and extended cause codeds and makes the length decision automatically. - Use only this function to append cause codes Change-Id: I71d58fad89502a43532f60717ca022c15c73f8bb