lib/ax25.c

   1 /*
   2  * lib/ax25.c This file contains an implementation of the "AX.25"
   3  *              support functions.
   4  *
   5  * Version:     $Id: ax25.c,v 1.9 1999/09/27 11:00:45 philip Exp $
   6  *
   7  * NOTE:        I will redo this module as soon as I got the libax25.a
   8  *              library sorted out.  This library contains some useful
   9  *              and often used address conversion functions, database
  10  *              lookup stuff, and more of the like.
  11  *
  12  * Author:      Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
  13  *              Copyright 1993 MicroWalt Corporation
  14  *
  15  *              This program is free software; you can redistribute it
  16  *              and/or  modify it under  the terms of  the GNU General
  17  *              Public  License as  published  by  the  Free  Software
  18  *              Foundation;  either  version 2 of the License, or  (at
  19  *              your option) any later version.
  20  */
  21 #include "config.h"
  22
  23 #if HAVE_AFAX25 || HAVE_HWAX25
  24 #include <sys/types.h>
  25 #include <sys/ioctl.h>
  26 #include <sys/socket.h>
  27 #if (__GLIBC__ > 2) || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 1)
  28 #include <netax25/ax25.h>
  29 #else
  30 #include <linux/ax25.h>
  31 #endif
  32 #include <net/if_arp.h>
  33 #include <stdlib.h>
  34 #include <stdio.h>
  35 #include <ctype.h>
  36 #include <errno.h>
  37 #include <fcntl.h>
  38 #include <string.h>
  39 #include <termios.h>
  40 #include <unistd.h>
  41 #include "net-support.h"
  42 #include "pathnames.h"
  43 #include "intl.h"
  44 #include "util.h"
  45
  46 static char AX25_errmsg[128];
  47
  48 extern struct aftype ax25_aftype;
  49
  50 static char *AX25_print(unsigned char *ptr)
  51 {
  52     static char buff[8];
  53     int i;
  54
  55     for (i = 0; i < 6; i++) {
  56         buff[i] = ((ptr[i] & 0377) >> 1);
  57         if (buff[i] == ' ')
  58             buff[i] = '\0';
  59     }
  60     buff[6] = '\0';
  61     i = ((ptr[6] & 0x1E) >> 1);
  62     if (i != 0)
  63         sprintf(&buff[strlen(buff)], "-%d", i);
  64     return (buff);
  65 }
  66
  67
  68 /* Display an AX.25 socket address. */
  69 static char *
  70  AX25_sprint(struct sockaddr *sap, int numeric)
  71 {
  72     static char buf[64];
  73
  74     if (sap->sa_family == 0xFFFF || sap->sa_family == 0)
  75         return safe_strncpy(buf, _("[NONE SET]"), sizeof(buf));
  76     return (AX25_print(((struct sockaddr_ax25 *) sap)->sax25_call.ax25_call));
  77 }
  78
  79
  80 static int AX25_input(int type, char *bufp, struct sockaddr *sap)
  81 {
  82     unsigned char *ptr;
  83     char *orig, c;
  84     int i;
  85
  86     sap->sa_family = ax25_aftype.af;
  87     ptr = ((struct sockaddr_ax25 *) sap)->sax25_call.ax25_call;
  88
  89     /* First, scan and convert the basic callsign. */
  90     orig = bufp;
  91     i = 0;
  92     while ((*bufp != '\0') && (*bufp != '-') && (i < 6)) {
  93         c = *bufp++;
  94         if (islower(c))
  95             c = toupper(c);
  96         if (!(isupper(c) || isdigit(c))) {
  97             safe_strncpy(AX25_errmsg, _("Invalid callsign"), sizeof(AX25_errmsg));
  98 #ifdef DEBUG
  99             fprintf(stderr, "ax25_input(%s): %s !\n", AX25_errmsg, orig);
 100 #endif
 101             errno = EINVAL;
 102             return (-1);
 103         }
 104         *ptr++ = (unsigned char) ((c << 1) & 0xFE);
 105         i++;
 106     }
 107
 108     /* Callsign too long? */
 109     if ((i == 6) && (*bufp != '-') && (*bufp != '\0')) {
 110         strcpy(AX25_errmsg, _("Callsign too long"));
 111 #ifdef DEBUG
 112         fprintf(stderr, "ax25_input(%s): %s !\n", AX25_errmsg, orig);
 113 #endif
 114         errno = E2BIG;
 115         return (-1);
 116     }
 117     /* Nope, fill out the address bytes with blanks. */
 118     while (i++ < sizeof(ax25_address) - 1) {
 119         *ptr++ = (unsigned char) ((' ' << 1) & 0xFE);
 120     }
 121
 122     /* See if we need to add an SSID field. */
 123     if (*bufp == '-') {
 124         i = atoi(++bufp);
 125         *ptr = (unsigned char) ((i << 1) & 0xFE);
 126     } else {
 127         *ptr = (unsigned char) '\0';
 128     }
 129
 130     /* All done. */
 131 #ifdef DEBUG
 132     fprintf(stderr, "ax25_input(%s): ", orig);
 133     for (i = 0; i < sizeof(ax25_address); i++)
 134         fprintf(stderr, "%02X ", sap->sa_data[i] & 0377);
 135     fprintf(stderr, "\n");
 136 #endif
 137
 138     return (0);
 139 }
 140
 141
 142 /* Display an error message. */
 143 static void AX25_herror(char *text)
 144 {
 145     if (text == NULL)
 146         fprintf(stderr, "%s\n", AX25_errmsg);
 147     else
 148         fprintf(stderr, "%s: %s\n", text, AX25_errmsg);
 149 }
 150
 151
 152 static int AX25_hinput(char *bufp, struct sockaddr *sap)
 153 {
 154     if (AX25_input(0, bufp, sap) < 0)
 155         return (-1);
 156     sap->sa_family = ARPHRD_AX25;
 157     return (0);
 158 }
 159
 160 #if 0
 161 /* Set the line discipline of a terminal line. */
 162 static int KISS_set_disc(int fd, int disc)
 163 {
 164     if (ioctl(fd, TIOCSETD, &disc) < 0) {
 165         fprintf(stderr, "KISS_set_disc(%d): %s\n", disc, strerror(errno));
 166         return (-errno);
 167     }
 168     return (0);
 169 }
 170
 171
 172 /* Start the KISS encapsulation on the file descriptor. */
 173 static int KISS_init(int fd)
 174 {
 175     if (KISS_set_disc(fd, N_SLIP) < 0)
 176         return (-1);
 177     if (ioctl(fd, SIOCSIFENCAP, 4) < 0)
 178         return (-1);
 179     return (0);
 180 }
 181 #endif
 182
 183 struct hwtype ax25_hwtype =
 184 {
 185     "ax25", NULL, /*"AMPR AX.25", */ ARPHRD_AX25, 7,
 186     AX25_print, AX25_hinput, NULL
 187 };
 188
 189 struct aftype ax25_aftype =
 190 {
 191     "ax25", NULL, /*"AMPR AX.25", */ AF_AX25, 7,
 192     AX25_print, AX25_sprint, AX25_input, AX25_herror,
 193     NULL, NULL, NULL,
 194     -1,
 195     "/proc/net/ax25"
 196 };
 197
 198 #endif                          /* HAVE_xxAX25 */