Harald Welte | c676c68 | 2017-12-24 20:38:20 +0100 | [diff] [blame] | 1 | module IuUP_Emulation { |
| 2 | |
Harald Welte | 35bb716 | 2018-01-03 21:07:52 +0100 | [diff] [blame] | 3 | /* IuUP emulation, uses the encoding/decoding from IuUP_Types. |
| 4 | * |
| 5 | * rather than running in a separate component with related primitives, |
| 6 | * we just implement a set of functions and data types which can be used |
| 7 | * by other code (such as an RTP endpoint) to implement IuUP support. |
| 8 | * |
| 9 | * (C) 2017 by Harald Welte <laforge@gnumonks.org> |
| 10 | * All rights reserved. |
| 11 | * |
| 12 | * Released under the terms of GNU General Public License, Version 2 or |
| 13 | * (at your option) any later version. |
| 14 | */ |
| 15 | |
| 16 | |
Harald Welte | c676c68 | 2017-12-24 20:38:20 +0100 | [diff] [blame] | 17 | import from Osmocom_Types all; |
| 18 | import from IuUP_Types all; |
| 19 | |
| 20 | |
| 21 | type record IuUP_RabFlowCombination { |
| 22 | IuUP_RFCI rfci, |
| 23 | /* number of bits per sub-flow */ |
| 24 | RecOfU8 sub_flow_bits, |
| 25 | /* IPTI value in number of ITIs for the corresponding RFCI */ |
| 26 | uint8_t ipti |
| 27 | }; |
| 28 | |
| 29 | template (value) IuUP_RabFlowCombination t_IuUP_RFC(IuUP_RFCI rfci, RecOfU8 subflow_bits, uint8_t ipti) := { |
| 30 | rfci := rfci, |
| 31 | sub_flow_bits := subflow_bits, |
| 32 | ipti := ipti |
| 33 | } |
| 34 | |
| 35 | template (value) IuUP_RabFlowCombination t_IuUP_RFC_AMR_12_2(IuUP_RFCI rfci) := t_IuUP_RFC(rfci, {81, 103, 60}, 1); |
| 36 | template (value) IuUP_RabFlowCombination t_IuUP_RFC_AMR_SID(IuUP_RFCI rfci) := t_IuUP_RFC(rfci, {34, 0, 0}, 7); |
| 37 | |
| 38 | type record IuUP_Config { |
| 39 | /* actively send INIT (true) or only passively respond (false) */ |
| 40 | boolean active_init, |
| 41 | boolean data_pdu_type_0, |
| 42 | /* RAB Flow Combinations */ |
| 43 | record of IuUP_RabFlowCombination rab_flow_combs |
| 44 | }; |
| 45 | |
| 46 | type enumerated IuUP_Em_State { |
| 47 | ST_INIT, |
| 48 | ST_DATA_TRANSFER_READY |
| 49 | }; |
| 50 | |
| 51 | |
| 52 | |
| 53 | type record IuUP_Entity { |
| 54 | IuUP_Config cfg, |
| 55 | IuUP_Em_State state, |
| 56 | IuUP_FrameNr tx_next_frame_nr, |
| 57 | IuUP_FrameNr rx_last_frame_nr optional, |
| 58 | IuUP_PDU pending_tx_pdu optional |
| 59 | }; |
| 60 | |
| 61 | template (value) IuUP_Entity t_IuUP_Entity(boolean act_init) := { |
| 62 | cfg := { |
| 63 | active_init := act_init, |
| 64 | data_pdu_type_0 := true, |
| 65 | rab_flow_combs := { t_IuUP_RFC_AMR_12_2(0), t_IuUP_RFC_AMR_SID(1) } |
| 66 | }, |
| 67 | state := ST_INIT, |
| 68 | tx_next_frame_nr := 0, |
| 69 | rx_last_frame_nr := omit, |
| 70 | pending_tx_pdu := omit |
| 71 | } |
| 72 | |
| 73 | |
| 74 | function f_IuUP_Em_rx_decaps(inout IuUP_Entity st, octetstring inp) return octetstring { |
| 75 | var IuUP_PDU pdu := dec_IuUP_PDU(inp); |
| 76 | if (ischosen(pdu.type_0)) { |
| 77 | if (st.cfg.data_pdu_type_0) { |
| 78 | /* FIXME: check header / CRC */ |
| 79 | st.rx_last_frame_nr := pdu.type_0.frame_nr; |
| 80 | return pdu.type_0.payload; |
| 81 | } else { |
| 82 | setverdict(fail, "PDU Type 0 received but 1 configured"); |
Daniel Willmann | e4ff537 | 2018-07-05 17:35:03 +0200 | [diff] [blame] | 83 | mtc.stop; |
Harald Welte | c676c68 | 2017-12-24 20:38:20 +0100 | [diff] [blame] | 84 | } |
| 85 | } else if (ischosen(pdu.type_1)) { |
| 86 | if (st.cfg.data_pdu_type_0 == false) { |
| 87 | /* FIXME: check header / CRC */ |
| 88 | st.rx_last_frame_nr := pdu.type_1.frame_nr; |
| 89 | return pdu.type_1.payload; |
| 90 | } else { |
| 91 | setverdict(fail, "PDU Type 1 received but 0 configured"); |
Daniel Willmann | e4ff537 | 2018-07-05 17:35:03 +0200 | [diff] [blame] | 92 | mtc.stop; |
Harald Welte | c676c68 | 2017-12-24 20:38:20 +0100 | [diff] [blame] | 93 | } |
| 94 | } else if (ischosen(pdu.type_14)) { |
| 95 | if (match(pdu, tr_IuUP_INIT)) { |
| 96 | if (st.cfg.active_init == true) { |
| 97 | setverdict(fail, "INIT received in ACTIVE role"); |
Daniel Willmann | e4ff537 | 2018-07-05 17:35:03 +0200 | [diff] [blame] | 98 | mtc.stop; |
Harald Welte | c676c68 | 2017-12-24 20:38:20 +0100 | [diff] [blame] | 99 | } else { |
| 100 | /* store an INIT_ACK to be transmitted later */ |
| 101 | st.pending_tx_pdu := valueof(ts_IuUP_INIT_ACK(pdu.type_14.frame_nr, |
| 102 | pdu.type_14.iuup_version)); |
| 103 | } |
| 104 | } else if (match(pdu, tr_IuUP_INIT_ACK)) { |
| 105 | if (st.cfg.active_init == true) { |
| 106 | log("IuUP INIT_ACK Received"); |
| 107 | st.state := ST_DATA_TRANSFER_READY; |
| 108 | } else { |
| 109 | setverdict(fail, "INIT_ACK received in PASSIVE role"); |
Daniel Willmann | e4ff537 | 2018-07-05 17:35:03 +0200 | [diff] [blame] | 110 | mtc.stop; |
Harald Welte | c676c68 | 2017-12-24 20:38:20 +0100 | [diff] [blame] | 111 | } |
| 112 | } |
| 113 | return ''O; |
| 114 | } else { |
| 115 | setverdict(fail, "Impossible IuUP PDU decoded from ", inp); |
Daniel Willmann | e4ff537 | 2018-07-05 17:35:03 +0200 | [diff] [blame] | 116 | mtc.stop; |
Harald Welte | c676c68 | 2017-12-24 20:38:20 +0100 | [diff] [blame] | 117 | } |
| 118 | self.stop; |
| 119 | } |
| 120 | |
| 121 | function f_IuUP_Em_tx_encap(inout IuUP_Entity st, in octetstring payload) return octetstring { |
| 122 | var IuUP_PDU pdu; |
| 123 | select (st.state) { |
| 124 | case (ST_INIT) { |
| 125 | if (st.cfg.active_init) { |
| 126 | /* send INIT */ |
| 127 | pdu := valueof(ts_IuUP_INIT('160051673C01270000820000001710000100'O)); |
| 128 | } else { |
| 129 | /* wait for INIT */ |
| 130 | if (isvalue(st.pending_tx_pdu)) { |
| 131 | /* we're waiting to transmit the INIT_ACK in response to an |
| 132 | * init (passive) */ |
| 133 | pdu := st.pending_tx_pdu; |
| 134 | st.pending_tx_pdu := omit; |
| 135 | st.state := ST_DATA_TRANSFER_READY; |
| 136 | } |
| 137 | } |
| 138 | } |
| 139 | case (ST_DATA_TRANSFER_READY) { |
| 140 | if (st.cfg.data_pdu_type_0) { |
| 141 | pdu := valueof(ts_IuUP_Type0(st.tx_next_frame_nr, 0, payload)); |
| 142 | } else { |
| 143 | pdu := valueof(ts_IuUP_Type1(st.tx_next_frame_nr, 0, payload)); |
| 144 | } |
| 145 | st.tx_next_frame_nr := st.tx_next_frame_nr + 1; |
| 146 | } |
| 147 | } |
| 148 | if (isvalue(pdu)) { |
| 149 | return f_enc_IuUP_PDU(pdu); |
| 150 | } else { |
| 151 | return ''O; |
| 152 | } |
| 153 | } |
| 154 | |
| 155 | |
| 156 | } |