lib/masq_info.c

   1 /*
   2  * lib/masq_info.c    This file contains a the functio masq_info
   3  *                      to print a table of current masquerade connections.
   4  *
   5  * NET-LIB      A collection of functions used from the base set of the
   6  *              NET-3 Networking Distribution for the LINUX operating
   7  *              system. (net-tools, net-drivers)
   8  *
   9  * Version:     $Id: masq_info.c,v 1.6 1999/06/12 23:04:19 philip Exp $
  10  *
  11  * Author:      Bernd 'eckes' Eckenfels <net-tools@lina.inka.de>
  12  *              Copyright 1999 Bernd Eckenfels, Germany
  13  *
  14  * Modifications:
  15  *
  16  *960217 {0.01} Bernd Eckenfels:        creatin from the code of
  17  *                                      Jos Vos' ipfwadm 2.0beta1
  18  *950218 {0.02} Bernd Eckenfels:        <linux/if.h> added
  19  *
  20  *980405 {0.03} Arnaldo Carvalho:       i18n CATGETS -> gettext
  21  *
  22  *              This program is free software; you can redistribute it
  23  *              and/or  modify it under  the terms of  the GNU General
  24  *              Public  License as  published  by  the  Free  Software
  25  *              Foundation;  either  version 2 of the License, or  (at
  26  *              your option) any later version.
  27  */
  28 #include <sys/types.h>
  29 #include <sys/socket.h>
  30 #include <netinet/in.h>
  31 #include <arpa/inet.h>
  32 #include <errno.h>
  33 #include <stdio.h>
  34 #include <malloc.h>
  35 #include <string.h>
  36 #include <unistd.h>
  37 #include "net-support.h"
  38 #include "pathnames.h"
  39 #include "version.h"
  40 #include "config.h"
  41 #include "intl.h"
  42 #include "net-features.h"
  43
  44 #if HAVE_FW_MASQUERADE
  45
  46 struct masq {
  47     unsigned long expires;      /* Expiration timer */
  48     char *proto;                /* Which protocol are we talking? */
  49     struct sockaddr_in src, dst;        /* Source and destination IP addresses */
  50     unsigned short sport, dport;        /* Source and destination ports */
  51     unsigned short mport;       /* Masqueraded port */
  52     unsigned long initseq;      /* Add delta from this seq. on */
  53     short delta;                /* Delta in sequence numbers */
  54     short pdelta;               /* Delta in sequence numbers before last */
  55 };
  56
  57 static struct aftype *ap;       /* current address family       */
  58 static int has_pdelta;
  59
  60 static void print_masq(struct masq *ms, int numeric, int ext)
  61 {
  62     unsigned long minutes, seconds, sec100s;
  63
  64     printf("%-4s", ms->proto);
  65
  66     sec100s = ms->expires % 100L;
  67     seconds = (ms->expires / 100L) % 60;
  68     minutes = ms->expires / 6000L;
  69
  70     printf("%3ld:%02ld.%02ld ", minutes, seconds, sec100s);
  71
  72     if (ext > 1) {
  73         if (has_pdelta)
  74             printf("%10lu %5hd %5hd ", ms->initseq,
  75                    ms->delta, ms->pdelta);
  76         else
  77             printf("%10lu %5hd     - ", ms->initseq,
  78                    ms->delta);
  79     }
  80     printf("%-20s ", ap->sprint((struct sockaddr *) &(ms->src), numeric));
  81     printf("%-20s ", ap->sprint((struct sockaddr *) &(ms->dst), numeric));
  82
  83     printf("%s -> ", get_sname(ms->sport, ms->proto, numeric));
  84     printf("%s", get_sname(ms->dport, ms->proto, numeric));
  85     printf(" (%s)\n", get_sname(ms->mport, ms->proto, numeric));
  86 }
  87
  88
  89 static int read_masqinfo(FILE * f, struct masq *mslist, int nmslist)
  90 {
  91     int n, nread = 0;
  92     struct masq *ms;
  93     char buf[256];
  94
  95     for (nread = 0; nread < nmslist; nread++) {
  96         ms = &mslist[nread];
  97         if (has_pdelta) {
  98             if ((n = fscanf(f, " %s %lX:%hX %lX:%hX %hX %lX %hd %hd %lu",
  99                             buf,
 100                   (unsigned long *) &ms->src.sin_addr.s_addr, &ms->sport,
 101                   (unsigned long *) &ms->dst.sin_addr.s_addr, &ms->dport,
 102                             &ms->mport, &ms->initseq, &ms->delta,
 103                             &ms->pdelta, &ms->expires)) == -1)
 104                 return nread;
 105         } else {
 106             if ((n = fscanf(f, " %s %lX:%hX %lX:%hX %hX %lX %hd %lu",
 107                             buf,
 108                   (unsigned long *) &ms->src.sin_addr.s_addr, &ms->sport,
 109                   (unsigned long *) &ms->dst.sin_addr.s_addr, &ms->dport,
 110                             &ms->mport, &ms->initseq, &ms->delta,
 111                             &ms->expires)) == -1)
 112                 return nread;
 113         }
 114         if ((has_pdelta && (n != 10)) || (!has_pdelta && (n != 9))) {
 115             EINTERN("masq_info.c", "ip_masquerade format error");
 116             return (-1);
 117         }
 118         ms->src.sin_family = AF_INET;
 119         ms->dst.sin_family = AF_INET;
 120
 121         if (strcmp("TCP", buf) == 0)
 122             ms->proto = "tcp";
 123         else if (strcmp("UDP", buf) == 0)
 124             ms->proto = "udp";
 125         else if (strcmp("ICMP", buf) == 0)
 126             ms->proto = "icmp";
 127         else if (strcmp("GRE", buf) == 0)
 128             ms->proto = "gre";
 129         else if (strcmp("ESP", buf) == 0)
 130             ms->proto = "esp";
 131         else {
 132             EINTERN("masq_info.c", "ip_masquerade unknown type");
 133             return (-1);
 134         }
 135
 136         /* we always keep these addresses in network byte order */
 137         ms->src.sin_addr.s_addr = htonl(ms->src.sin_addr.s_addr);
 138         ms->dst.sin_addr.s_addr = htonl(ms->dst.sin_addr.s_addr);
 139         ms->sport = htons(ms->sport);
 140         ms->dport = htons(ms->dport);
 141         ms->mport = htons(ms->mport);
 142     }
 143     return nread;
 144 }
 145
 146
 147 int ip_masq_info(int numeric, int ext)
 148 {
 149     FILE *f;
 150     int i;
 151     char buf[256];
 152     struct masq *mslist;
 153     int ntotal = 0, nread;
 154
 155     if (!(f = fopen(_PATH_PROCNET_IP_MASQ, "r"))) {
 156         if (errno != ENOENT) {
 157             perror(_PATH_PROCNET_IP_MASQ);
 158             return (-1);
 159         }
 160         ESYSNOT("netstat", "ip_masquerade");
 161         return (1);
 162     }
 163     if ((ap = get_aftype("inet")) == NULL) {
 164         ENOSUPP("masq_info", "AF INET");
 165         fclose(f);
 166         return (-1);
 167     }
 168     fgets(buf, sizeof(buf), f);
 169     has_pdelta = strstr(buf, "PDelta") ? 1 : 0;
 170
 171     mslist = (struct masq *) malloc(16 * sizeof(struct masq));
 172     if (!mslist) {
 173         EINTERN("masq_info", "malloc() failed");
 174         fclose(f);
 175         return (-1);
 176     }
 177     while ((nread = read_masqinfo(f, &(mslist[ntotal]), 16)) == 16) {
 178         ntotal += nread;
 179         mslist = (struct masq *) realloc(mslist,
 180                                     (ntotal + 16) * sizeof(struct masq));
 181         if (!mslist) {
 182             EINTERN("masq_info", "realloc() failed");
 183             fclose(f);
 184             return (-1);
 185         }
 186     }
 187     fclose(f);
 188
 189     if (nread < 0) {
 190         if (mslist)
 191             free(mslist);
 192         return (-1);
 193     }
 194     ntotal += nread;
 195
 196     if (ntotal > 0) {
 197         printf(_("IP masquerading entries\n"));
 198         switch (ext) {
 199         case 1:
 200             printf(_("prot   expire source               destination          ports\n"));
 201             break;
 202         default:
 203             printf(_("prot   expire    initseq delta prevd source               destination          ports\n"));
 204             break;
 205         }
 206         for (i = 0; i < ntotal; i++)
 207             print_masq(&(mslist[i]), numeric, ext);
 208         if (mslist)
 209             free(mslist);
 210
 211     }
 212     return 0;
 213 }
 214 #endif