pri_q921.h

   1 /*
   2  * libpri: An implementation of Primary Rate ISDN
   3  *
   4  * Written by Mark Spencer <markster@digium.com>
   5  *
   6  * Copyright (C) 2001, Digium, Inc.
   7  * All Rights Reserved.
   8  * Copyright (C) 2003-2006 Junghanns.NET GmbH
   9  * Klaus-Peter Junghanns <kpj@junghanns.net>
  10  */
  11
  12 /*
  13  * See http://www.asterisk.org for more information about
  14  * the Asterisk project. Please do not directly contact
  15  * any of the maintainers of this project for assistance;
  16  * the project provides a web site, mailing lists and IRC
  17  * channels for your use.
  18  *
  19  * This program is free software, distributed under the terms of
  20  * the GNU General Public License Version 2 as published by the
  21  * Free Software Foundation. See the LICENSE file included with
  22  * this program for more details.
  23  */
  24
  25 #ifndef _PRI_Q921_H
  26 #define _PRI_Q921_H
  27
  28 #include <sys/types.h>
  29 #if defined(__linux__)
  30 #include <endian.h>
  31 #elif defined(__FreeBSD__)
  32 #include <sys/endian.h>
  33 #define __BYTE_ORDER _BYTE_ORDER
  34 #define __BIG_ENDIAN _BIG_ENDIAN
  35 #define __LITTLE_ENDIAN _LITTLE_ENDIAN
  36 #endif
  37
  38 /* Timer values */
  39
  40 #define T_WAIT_MIN      2000
  41 #define T_WAIT_MAX      10000
  42
  43 #define Q921_FRAMETYPE_MASK     0x3
  44
  45 #define Q921_FRAMETYPE_U        0x3
  46 #define Q921_FRAMETYPE_I        0x0
  47 #define Q921_FRAMETYPE_S        0x1
  48
  49 #define Q921_TEI_GROUP                          127
  50 #define Q921_TEI_ID_REQUEST     0x1
  51 #define Q921_TEI_ID_ASSIGNED    0x2
  52 #define Q921_TEI_ID_DENIED      0x3
  53 #define Q921_TEI_ID_CHK_REQ     0x4
  54 #define Q921_TEI_ID_CHK_RES     0x5
  55 #define Q921_TEI_ID_REMOVE      0x6
  56 #define Q921_TEI_ID_VERIFY      0x7
  57 #define Q921_TEI_GR303_EOC_PATH                 0
  58 #define Q921_TEI_GR303_EOC_OPS                  4
  59 #define Q921_TEI_GR303_TMC_SWITCHING            0
  60 #define Q921_TEI_GR303_TMC_CALLPROC             0
  61
  62 #define Q921_SAPI_CALL_CTRL             0
  63 #define Q921_SAPI_GR303_EOC             1
  64 #define Q921_SAPI_GR303_TMC_SWITCHING   1
  65 #define Q921_SAPI_GR303_TMC_CALLPROC    0
  66
  67
  68 #define Q921_SAPI_PACKET_MODE           1
  69 #define Q921_SAPI_X25_LAYER3            16
  70 #define Q921_SAPI_LAYER2_MANAGEMENT     63
  71
  72
  73 typedef struct q921_header {
  74 #if __BYTE_ORDER == __BIG_ENDIAN
  75         u_int8_t        sapi:6; /* Service Access Point Indentifier (always 0 for PRI) (0) */
  76         u_int8_t        c_r:1;          /* Command/Response (0 if CPE, 1 if network) */
  77         u_int8_t        ea1:1;          /* Extended Address (0) */
  78         u_int8_t        tei:7;          /* Terminal Endpoint Identifier (0) */
  79         u_int8_t        ea2:1;          /* Extended Address Bit (1) */
  80 #else
  81         u_int8_t        ea1:1;          /* Extended Address (0) */
  82         u_int8_t        c_r:1;          /* Command/Response (0 if CPE, 1 if network) */
  83         u_int8_t        sapi:6; /* Service Access Point Indentifier (always 0 for PRI) (0) */
  84         u_int8_t        ea2:1;          /* Extended Address Bit (1) */
  85         u_int8_t        tei:7;          /* Terminal Endpoint Identifier (0) */
  86 #endif
  87         u_int8_t        data[0];        /* Further data */
  88 } __attribute__ ((packed)) q921_header;
  89
  90 /* A Supervisory Format frame */
  91 typedef struct q921_s {
  92         struct q921_header h;   /* Header */
  93 #if __BYTE_ORDER == __BIG_ENDIAN
  94         u_int8_t x0:4;                  /* Unused */
  95         u_int8_t ss:2;                  /* Supervisory frame bits */
  96         u_int8_t ft:2;                  /* Frame type bits (01) */
  97         u_int8_t n_r:7;                 /* Number Received */
  98         u_int8_t p_f:1;                 /* Poll/Final bit */
  99 #else
 100         u_int8_t ft:2;                  /* Frame type bits (01) */
 101         u_int8_t ss:2;                  /* Supervisory frame bits */
 102         u_int8_t x0:4;                  /* Unused */
 103         u_int8_t p_f:1;                 /* Poll/Final bit */
 104         u_int8_t n_r:7;                 /* Number Received */
 105 #endif
 106         u_int8_t data[0];               /* Any further data */
 107         u_int8_t fcs[2];                /* At least an FCS */
 108 } __attribute__ ((packed)) q921_s;
 109
 110 /* An Unnumbered Format frame */
 111 typedef struct q921_u {
 112         struct q921_header h;   /* Header */
 113 #if __BYTE_ORDER == __BIG_ENDIAN
 114         u_int8_t m3:3;                  /* Top 3 modifier bits */
 115         u_int8_t p_f:1;                 /* Poll/Final bit */
 116         u_int8_t m2:2;                  /* Two more modifier bits */
 117         u_int8_t ft:2;                  /* Frame type bits (11) */
 118 #else
 119         u_int8_t ft:2;                  /* Frame type bits (11) */
 120         u_int8_t m2:2;                  /* Two more modifier bits */
 121         u_int8_t p_f:1;                 /* Poll/Final bit */
 122         u_int8_t m3:3;                  /* Top 3 modifier bits */
 123 #endif
 124         u_int8_t data[0];               /* Any further data */
 125         u_int8_t fcs[2];                /* At least an FCS */
 126 } __attribute__ ((packed)) q921_u;
 127
 128 /* An Information frame */
 129 typedef struct q921_i {
 130         struct q921_header h;   /* Header */
 131 #if __BYTE_ORDER == __BIG_ENDIAN
 132         u_int8_t n_s:7;                 /* Number sent */
 133         u_int8_t ft:1;                  /* Frame type (0) */
 134         u_int8_t n_r:7;                 /* Number received */
 135         u_int8_t p_f:1;                 /* Poll/Final bit */
 136 #else
 137         u_int8_t ft:1;                  /* Frame type (0) */
 138         u_int8_t n_s:7;                 /* Number sent */
 139         u_int8_t p_f:1;                 /* Poll/Final bit */
 140         u_int8_t n_r:7;                 /* Number received */
 141 #endif
 142         u_int8_t data[0];               /* Any further data */
 143         u_int8_t fcs[2];                /* At least an FCS */
 144 } q921_i;
 145
 146 typedef union {
 147         u_int8_t raw[0];
 148         q921_u u;
 149         q921_s s;
 150         q921_i i;
 151         struct q921_header h;
 152 } q921_h;
 153
 154 typedef struct q921_frame {
 155         struct q921_frame *next;        /* Next in list */
 156         int len;                                        /* Length of header + body */
 157         int transmitted;                        /* Have we been transmitted */
 158         q921_i h;
 159 } q921_frame;
 160
 161 #define Q921_INC(j) (j) = (((j) + 1) % 128)
 162
 163 typedef enum q921_state {
 164         Q921_LINK_CONNECTION_RELEASED,  /* Also known as TEI_ASSIGNED */
 165         Q921_LINK_CONNECTION_ESTABLISHED,
 166         Q921_AWAITING_ESTABLISH,
 167         Q921_AWAITING_RELEASE
 168 } q921_state;
 169
 170 /* Dumps a *known good* Q.921 packet */
 171 extern void q921_dump(struct pri *pri, q921_h *h, int len, int showraw, int txrx);
 172
 173 /* Bring up the D-channel */
 174 extern void q921_start(struct pri *pri, int now, int tei);
 175
 176 extern void q921_reset(struct pri *pri, int tei, int discard);
 177
 178 extern pri_event *q921_receive(struct pri *pri, q921_h *h, int len);
 179
 180 extern int q921_transmit_uframe(struct pri *pri, void *buf, int len, int cr, int tei);
 181
 182 extern int q921_transmit_iframe(struct pri *pri, void *buf, int len, int cr, int tei);
 183
 184 #endif