Harald Welte | 02acf82 | 2019-09-23 06:05:52 +0200 | [diff] [blame] | 1 | module SABP_Adapter { |
| 2 | |
| 3 | /* SABP Adapter layer, sitting on top of SABP_CodecPort. |
| 4 | * test suites can 'inherit' in order to have a SABP connection to the IUT which they're testing |
| 5 | * |
| 6 | * (C) 2019 by Harald Welte <laforge@gnumonks.org> |
| 7 | * All rights reserved. |
| 8 | * |
| 9 | * Released under the terms of GNU General Public License, Version 2 or |
| 10 | * (at your option) any later version. |
| 11 | */ |
| 12 | |
| 13 | |
| 14 | import from Osmocom_Types all; |
| 15 | import from General_Types all; |
| 16 | import from SABP_Types all; |
| 17 | import from SABP_PDU_Descriptions all; |
| 18 | import from SABP_Templates all; |
| 19 | import from SABP_CodecPort all; |
| 20 | import from SABP_CodecPort_CtrlFunct all; |
| 21 | import from IPL4asp_Types all; |
| 22 | import from IPL4asp_PortType all; |
| 23 | //import from Socket_API_Definitions all; |
| 24 | |
| 25 | const integer SABP_HDR_LEN := 3; |
| 26 | |
| 27 | const integer NUM_SABP := 3; |
| 28 | |
| 29 | type component SABP_Adapter_CT { |
| 30 | /* down-facing port to SABP Codec port */ |
| 31 | port SABP_CODEC_PT SABP[NUM_SABP]; |
| 32 | var IPL4asp_Types.ConnectionId g_sabp_conn_id[NUM_SABP] := { -1, -1, -1 }; |
| 33 | } |
| 34 | |
| 35 | /*! parse a single APER length determinant. Return -1 if input insufficient or -2 if invalid */ |
| 36 | private function f_aper_len_det(in octetstring stream, out integer len_len) return integer { |
| 37 | if (lengthof(stream) < 1) { |
| 38 | return -1; |
| 39 | } |
| 40 | |
| 41 | select (stream[0] and4b 'C0'O) { |
| 42 | case ('00'O) { |
| 43 | /* total length is encoded in this octet */ |
| 44 | len_len := 1; |
| 45 | return oct2int(stream[0]); |
| 46 | } |
| 47 | case ('80'O) { |
| 48 | /* total length (up to 16k) encoded in two octets */ |
| 49 | if (lengthof(stream) < 2) { |
| 50 | return -1; |
| 51 | } |
| 52 | len_len := 2; |
| 53 | return (oct2int(stream[0] and4b '3F'O) * 256) + oct2int(stream[1]); |
| 54 | } |
| 55 | case ('C0'O) { |
| 56 | /* total length not known, encoded in chunks; first chunk length now known */ |
| 57 | len_len := 1; |
| 58 | return oct2int(stream[0] and4b '3F'O) * 16384; |
| 59 | } |
| 60 | case else { |
| 61 | return -2; |
| 62 | } |
| 63 | |
| 64 | } |
| 65 | } |
| 66 | |
| 67 | /* The callback function has to return the length of the message if completely received. It has to return |
| 68 | * "-1" if the length cannot be determined. If the message is incomplete, but the length can be |
| 69 | * determined, then the function should return the length. In this case the callback function will not be |
| 70 | * called again for the given message - possibly increasing the performance. Alternatively the function may |
| 71 | * always return "-1" when the message is incomplete. |
| 72 | * If the callback function detects that the it will be impossible to determine the length of the message, |
| 73 | * even receiving more octets, should return "-2". In this case the connection will be closed and the |
| 74 | * length calculation error will be reported. */ |
| 75 | private function f_APER_getMsgLen(in octetstring stream, inout ro_integer args) return integer { |
| 76 | var integer stream_len := lengthof(stream); |
| 77 | var integer hdr_len := args[0]; |
| 78 | var octetstring stream_nohdr; |
| 79 | var integer len, len_len; |
| 80 | |
| 81 | if (stream_len < hdr_len + 1) { |
| 82 | return -1; |
| 83 | } |
| 84 | stream_nohdr := substr(stream, hdr_len, stream_len-hdr_len); |
| 85 | |
| 86 | len := f_aper_len_det(stream_nohdr, len_len); |
| 87 | if (len < 0) { |
| 88 | /* error: return to caller */ |
| 89 | return len; |
| 90 | } |
| 91 | if (len < 16384) { |
| 92 | /* full length is known: return to caller */ |
| 93 | return hdr_len + len_len + len; |
| 94 | } else { |
| 95 | /* 'cursor' to next length indicator */ |
| 96 | var integer cur := hdr_len + len_len + len; |
| 97 | /* iterate the whole chain of chunks */ |
| 98 | while (true) { |
| 99 | if (stream_len < cur + 1) { |
| 100 | return -1; |
| 101 | } |
| 102 | len := f_aper_len_det(substr(stream, cur, stream_len-cur), len_len); |
| 103 | if (len < 0) { |
| 104 | /* error: return to caller */ |
| 105 | return len; |
| 106 | } |
| 107 | if (len < 16384) { |
| 108 | /* final chunk: segment with less than 16384 bytes */ |
| 109 | return cur + len_len + len; |
| 110 | } else { |
| 111 | /* point to next chunk */ |
| 112 | cur := cur + len_len + len; |
| 113 | } |
| 114 | } |
| 115 | } |
| 116 | /* not reached */ |
| 117 | return -2; |
| 118 | } |
| 119 | |
| 120 | private function f_set_tcp_segmentation(integer idx) runs on SABP_Adapter_CT { |
| 121 | /* Set function for dissecting the binary stream into packets */ |
| 122 | var f_IPL4_getMsgLen vl_f := refers(f_APER_getMsgLen); |
| 123 | /* Offset: 1, size of length: 3, delta: 4, multiplier: 1, big-endian */ |
| 124 | SABP_CodecPort_CtrlFunct.f_IPL4_setGetMsgLen(SABP[idx], g_sabp_conn_id[idx], vl_f, {SABP_HDR_LEN}); |
| 125 | } |
| 126 | |
| 127 | function f_connect(charstring remote_host, IPL4asp_Types.PortNumber remote_port, |
| 128 | charstring local_host, IPL4asp_Types.PortNumber local_port, integer idx := 0) |
| 129 | runs on SABP_Adapter_CT { |
| 130 | var IPL4asp_Types.Result res; |
| 131 | map(self:SABP[idx], system:SABP); |
| 132 | res := SABP_CodecPort_CtrlFunct.f_IPL4_connect(SABP[idx], remote_host, remote_port, |
| 133 | local_host, local_port, 0, { tcp :={} }); |
| 134 | if (not ispresent(res.connId)) { |
| 135 | setverdict(fail, "Could not connect to SABP port, check your configuration"); |
| 136 | mtc.stop; |
| 137 | } |
| 138 | g_sabp_conn_id[idx] := res.connId; |
| 139 | |
| 140 | f_set_tcp_segmentation(idx); |
| 141 | } |
| 142 | |
| 143 | /* Function to use to bind to a local port as IPA server, accepting remote clients */ |
| 144 | function f_bind(charstring local_host, IPL4asp_Types.PortNumber local_port, integer idx := 0) |
| 145 | runs on SABP_Adapter_CT { |
| 146 | var IPL4asp_Types.Result res; |
| 147 | map(self:SABP[idx], system:SABP); |
| 148 | res := SABP_CodecPort_CtrlFunct.f_IPL4_listen(SABP[idx], local_host, local_port, { tcp:={} }); |
| 149 | g_sabp_conn_id[idx] := res.connId; |
| 150 | |
| 151 | f_set_tcp_segmentation(idx); |
| 152 | } |
| 153 | |
| 154 | function f_sabp_send(template (value) SABP_PDU pdu, integer idx := 0) runs on SABP_Adapter_CT { |
| 155 | SABP[idx].send(ts_SABP_Send(g_sabp_conn_id[idx], pdu)); |
| 156 | } |
| 157 | |
| 158 | function f_sabp_exp(template SABP_PDU exp, integer idx := 0) runs on SABP_Adapter_CT return SABP_PDU { |
| 159 | var SABP_RecvFrom rf; |
| 160 | SABP[idx].receive(tr_SABP_Recv(g_sabp_conn_id[idx], exp)) -> value rf; |
| 161 | return rf.msg; |
| 162 | } |
| 163 | |
| 164 | |
| 165 | } |