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

   1 /* -*-c-*-
   2  *
   3  * $Id: ident.c,v 1.2 1999/07/26 23:26:44 mdw Exp $
   4  *
   5  * Parse replies from RFC931 servers
   6  *
   7  * (c) 1999 Straylight/Edgeware
   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 1.2  1999/07/26 23:26:44  mdw
  33  * Change copyright notice.
  34  *
  35  * Revision 1.1.1.1  1999/07/01 08:56:23  mdw
  36  * Initial revision.
  37  *
  38  * Revision 1.1.1.1  1999/05/21 22:22:27  mdw
  39  * Initial import.  Code not really finished yet.
  40  *
  41  */
  42
  43 /*----- Header files ------------------------------------------------------*/
  44
  45 #include <ctype.h>
  46 #include <stdio.h>
  47 #include <stdlib.h>
  48 #include <string.h>
  49
  50 #include "ident.h"
  51
  52 /*----- Main code ---------------------------------------------------------*/
  53
  54 /* --- @next@ --- *
  55  *
  56  * Arguments:   @char **pp@ = address of string pointer
  57  *
  58  * Returns:     Address of next token.
  59  *
  60  * Use:         Reads the next token from the result string.  Tokens are
  61  *              terminated by whitespace, or `:' or `,' characters.  The
  62  *              result string has had `\' escapes removed; it's stored in
  63  *              the same memory as the input string.  The actual content
  64  *              of the delimiter doesn't seem to be interesting, so it
  65  *              gets thrown away.
  66  */
  67
  68 static char *next(char **pp)
  69 {
  70   char *p, *q, *r;
  71
  72   /* --- Deal with reads past the end of the string --- */
  73
  74   if (!*pp)
  75     return ("");
  76
  77   /* --- Initialize various pointers into the string --- */
  78
  79   p = q = r = *pp;
  80
  81   /* --- Skip past any leading whitespace --- */
  82
  83   while (isspace((unsigned char)*p))
  84     p++;
  85
  86   /* --- Now start work on the string itself --- */
  87
  88   for (;;) {
  89     if (*p == 0 || *p == ':' || *p == ',' || isspace((unsigned char)*p))
  90       break;
  91     else if (*p == '\\') {
  92       p++;
  93       if (!*p) {
  94         *q++ = '\\';
  95         break;
  96       }
  97     }
  98     *q++ = *p++;
  99   }
 100
 101   /* --- Tidy up afterwards --- */
 102
 103   while (isspace((unsigned char)*p))
 104     p++;
 105   if (*p == 0)
 106     *pp = 0;
 107   else if (*p == ':' || *p == ',')
 108     *pp = p + 1;
 109   else
 110     *pp = p;
 111   *q = 0;
 112
 113   return (r);
 114 }
 115
 116 /* --- @ident_parse@ --- *
 117  *
 118  * Arguments:   @char *p@ = pointer to input string from identd
 119  *              @ident *i@ = pointer to output block
 120  *
 121  * Returns:     ---
 122  *
 123  * Use:         Parses a result string from an RFC931 (identd) server.
 124  */
 125
 126 void ident_parse(char *p, ident *i)
 127 {
 128   char *q;
 129
 130   /* --- Read the source and destination port numbers --- */
 131
 132   i->sport = atoi(next(&p));
 133   i->dport = atoi(next(&p));
 134
 135   /* --- Find out what sort of a reply this is --- */
 136
 137   q = next(&p);
 138   if (strcmp(q, "USERID") == 0) {
 139     i->type = ident_userid;
 140     i->u.userid.os = next(&p);
 141     i->u.userid.user = next(&p);
 142   } else if (strcmp(q, "ERROR") == 0) {
 143     i->type = ident_error;
 144     i->u.error = next(&p);
 145   } else
 146     i->type = ident_bad;
 147 }
 148
 149 /*----- That's all, folks -------------------------------------------------*/