mdw@git.distorted.org.uk Git - fwd/blob - ident.c

   1 /* -*-c-*-
   2  *
   3  * $Id: ident.c,v 1.1 1999/07/01 08:56:23 mdw Exp $
   4  *
   5  * Parse replies from RFC931 servers
   6  *
   7  * (c) 1999 Mark Wooding
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of the `fw' port forwarder.
  13  *
  14  * `fw' is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * `fw' is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with `fw'; if not, write to the Free Software Foundation,
  26  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  27  */
  28
  29 /*----- Revision history --------------------------------------------------*
  30  *
  31  * $Log: ident.c,v $
  32  * Revision 1.1  1999/07/01 08:56:23  mdw
  33  * Initial revision
  34  *
  35  * Revision 1.1.1.1  1999/05/21 22:22:27  mdw
  36  * Initial import.  Code not really finished yet.
  37  *
  38  */
  39
  40 /*----- Header files ------------------------------------------------------*/
  41
  42 #include <ctype.h>
  43 #include <stdio.h>
  44 #include <stdlib.h>
  45 #include <string.h>
  46
  47 #include "ident.h"
  48
  49 /*----- Main code ---------------------------------------------------------*/
  50
  51 /* --- @next@ --- *
  52  *
  53  * Arguments:   @char **pp@ = address of string pointer
  54  *
  55  * Returns:     Address of next token.
  56  *
  57  * Use:         Reads the next token from the result string.  Tokens are
  58  *              terminated by whitespace, or `:' or `,' characters.  The
  59  *              result string has had `\' escapes removed; it's stored in
  60  *              the same memory as the input string.  The actual content
  61  *              of the delimiter doesn't seem to be interesting, so it
  62  *              gets thrown away.
  63  */
  64
  65 static char *next(char **pp)
  66 {
  67   char *p, *q, *r;
  68
  69   /* --- Deal with reads past the end of the string --- */
  70
  71   if (!*pp)
  72     return ("");
  73
  74   /* --- Initialize various pointers into the string --- */
  75
  76   p = q = r = *pp;
  77
  78   /* --- Skip past any leading whitespace --- */
  79
  80   while (isspace((unsigned char)*p))
  81     p++;
  82
  83   /* --- Now start work on the string itself --- */
  84
  85   for (;;) {
  86     if (*p == 0 || *p == ':' || *p == ',' || isspace((unsigned char)*p))
  87       break;
  88     else if (*p == '\\') {
  89       p++;
  90       if (!*p) {
  91         *q++ = '\\';
  92         break;
  93       }
  94     }
  95     *q++ = *p++;
  96   }
  97
  98   /* --- Tidy up afterwards --- */
  99
 100   while (isspace((unsigned char)*p))
 101     p++;
 102   if (*p == 0)
 103     *pp = 0;
 104   else if (*p == ':' || *p == ',')
 105     *pp = p + 1;
 106   else
 107     *pp = p;
 108   *q = 0;
 109
 110   return (r);
 111 }
 112
 113 /* --- @ident_parse@ --- *
 114  *
 115  * Arguments:   @char *p@ = pointer to input string from identd
 116  *              @ident *i@ = pointer to output block
 117  *
 118  * Returns:     ---
 119  *
 120  * Use:         Parses a result string from an RFC931 (identd) server.
 121  */
 122
 123 void ident_parse(char *p, ident *i)
 124 {
 125   char *q;
 126
 127   /* --- Read the source and destination port numbers --- */
 128
 129   i->sport = atoi(next(&p));
 130   i->dport = atoi(next(&p));
 131
 132   /* --- Find out what sort of a reply this is --- */
 133
 134   q = next(&p);
 135   if (strcmp(q, "USERID") == 0) {
 136     i->type = ident_userid;
 137     i->u.userid.os = next(&p);
 138     i->u.userid.user = next(&p);
 139   } else if (strcmp(q, "ERROR") == 0) {
 140     i->type = ident_error;
 141     i->u.error = next(&p);
 142   } else
 143     i->type = ident_bad;
 144 }
 145
 146 /*----- That's all, folks -------------------------------------------------*/