Kouglof2/octave.c

/*******************************************************************
 Copyright (C) 2011-2024  Patrick H. E. Foubet - S.E.R.I.A.N.E.

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or any
later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>
*******************************************************************/

/*
 ############################################################
 #  Projet Kouglof 2 de l'Ecole du Logiciel Libre d'Ivry :  #
 ############################################################

 octave.c : outil pour scanner l'interface reseau afin d'analyser les sites
 auxquels les applications veulent se connecter.
 A utiliser avec le fichier auth1.txt pour stopper les connexions non voulues

Tous les details sur le site :
https://e2li.org -> menu : Projet Prosecco.

*/

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <unistd.h>
#include <signal.h>
#include <fcntl.h>
#include <readline/readline.h>
#include <readline/history.h>
#include <sys/wait.h>
#include <string.h>
#include <syslog.h>
#include <time.h>
#include <arpa/inet.h>
#include <pthread.h>

#define Version "1.00"

#define F_GETPIPE_SZ 1032
#define F_SETPIPE_SZ 1031

static int RUN=1, REQ=0, ENDT=0, REPR=0, p1[2],Trace=0;
static pid_t pid;
static char * NPROG, *IFACE=NULL;
#define DELAYR 20 /* delai avant relance auto */

void interup (int S)
{
   if (S==SIGINT) {
     write(p1[1],"\n",1);
     REQ=1; return;
   }
   if (S==SIGCHLD) {
     if (waitpid(pid,NULL,WNOHANG) == pid) {
        ENDT=1;
        write(p1[1],"\n",1);
     }
     return;
   }
   fprintf(stderr,"Reçu signal %d !!??\n",S);
}

/* ### les niveaux de trace */
#define TMIN 0
#define TMAX 3
#define T1 Trace > 0
#define T2 Trace > 1
#define T3 Trace > 2

/* #### les fonctions adresses IPv4 */

int isIPv4(char *a)
{
struct in_addr S;
int r;
   if ((r = inet_pton(AF_INET,a, (void *)&S)) <= 0) return 0;
   return 1;
}

int isCidr(char*r)
{
char buf[20], *sn;
int n;
   if (strlen(r)>18) return 0;
   strcpy(buf,r);
   if ((sn=strstr(buf,"/")) == NULL) return 0;
   *sn = '\0';
   if (!isIPv4(buf)) return 0;
   n = atoi(sn+1);
   if (n>32) return 0;
   return n;
}

int isSousRes(char*r, char *a)
{
struct in_addr Sa, Sr, Sm;
int n, m1,m2,m3,m4, m;
char buf[20],smasq[16],*sn;
   if (!isCidr(r)) return 0;
   if (!isIPv4(a)) return 0;
   strcpy(buf,r);
   if ((sn=strstr(buf,"/")) == NULL) return 0;
   *sn = '\0';
   n = atoi(sn+1);
   /* calcul du masq */
   m=n;
   if (m>7) { m1=255; m-=8;
   } else { m1=0;
      while (m>=0) m1 |= 0x80 >> --m;
   }
   if (m>7) { m2=255; m-=8;
   } else { m2=0;
      while (m>=0) m2 |= 0x80 >> --m;
   }
   if (m>7) { m3=255; m-=8;
   } else { m3=0;
      while (m>=0) m3 |= 0x80 >> --m;
   }
   if (m>7) { m4=255; m-=8;
   } else { m4=0;
      while (m>=0) m4 |= 0x80 >> --m;
   }
   sprintf(smasq,"%d.%d.%d.%d",m1,m2,m3,m4);
   inet_pton(AF_INET,smasq, (void *)&Sm);
   inet_pton(AF_INET,a, (void *)&Sa);
   inet_pton(AF_INET,buf, (void *)&Sr);
   if ((Sr.s_addr & Sm.s_addr) == (Sa.s_addr & Sm.s_addr)) return 1;
   return 0;
}

/* #### gestion dynamique des CIDR */

#define NBC 100  /* nb de CIDR */
char* Tcidr[NBC];
int iC=0;

int bloqueIP(char*);

int addCidr(char * c)
{
int i=iC;
  if (i==NBC) return i;
  Tcidr[i] = (char*)malloc(strlen(c)+1);
  strcpy(Tcidr[i],c);
  iC++;
  bloqueIP(c);
  return i;
}

void delCidr(char * c)
{
int i;
  for (i=0; i<iC; i++)
     if (strcmp(c,Tcidr[i]) == 0) {
        iC--;
        if (iC == i) return;
        if (iC > 0) Tcidr[i] = Tcidr[iC];
        return;
     }
}

int isAddrInCidr(char * a, int M)
{
int i;
   for(i=0;i<iC;i++) {
        if (isSousRes(Tcidr[i],a)) {
            if (M) syslog(LOG_INFO,"CIDR %s contient %s !",Tcidr[i],a);
            return 1;
        }
   }
   return 0;
}

void validCidr(void)
{
int i,j;
char a[20],*p, *g, *w;
   for(i=0;i<iC;i++)
     for (j=i+1;j<iC;j++) {
        if (isCidr(Tcidr[i]) < isCidr(Tcidr[j])) {
           p=Tcidr[i]; g=Tcidr[j];
        } else {
           p=Tcidr[j]; g=Tcidr[i];
        }
        strcpy(a,g);
        w = strstr(a,"/");
        *w = '\0';
        w++;
        if (isSousRes(p,a)) {
          if (T3) printf("T3: %s contient %s (%s)\n",p,a,w);
          delCidr(g);
        }
     }
}

void listCidr(void)
{
int i;
  printf("CIDR : %d\n",iC);
  for (i=0; i<iC; i++) printf("\t%s\n", Tcidr[i]);
}

/* ### gestion des listes */

#define NBAll 500
#define NBDen 300
char * Allow[NBAll];
char * Deny[NBDen];
int iAll=0, iDen=0;

int isDeny(char*u)
{
char *su;
int i, tu, t;
   for (i=0;i<iDen;i++) {
      tu = strlen(u);
      t  = strlen(Deny[i]);
      if (tu < t) continue;
      su = u + tu - t;;
      if (strcmp(su,Deny[i]) == 0) {
        if (su==u) return 1; 
        if (*(su-1)=='.') return 1; 
      }
   }
   for (i=0;i<iAll;i++) {
      tu = strlen(u);
      t  = strlen(Allow[i]);
      if (tu < t) continue;
      su = u + tu - t;
      if (strcmp(su,Allow[i]) == 0) {
        if (*(Allow[i]) == '.') return 0;
        if (su==u) return 0; 
        if (*(su-1)=='.') return 0; 
      }
   }
   return 1; /* deny par defaut */
}

void listeAllow(void)
{
int i;
   printf("Allow : %d\n",iAll);
   for (i=0;i<iAll;i++) printf("\t%s\n",Allow[i]);
}
void listeDeny(void)
{
int i;
   printf("Deny : %d\n",iDen);
   for (i=0;i<iDen;i++) printf("\t%s\n",Deny[i]);
}
void dejaLa(char * e)
{
    printf("%s est deja dans la liste !\n",e);
}
int dejaAllow(char *e)
{
int i;
   for (i=0;i<iAll;i++) {
        if (strlen(e) != strlen(Allow[i])) continue;
        if (strcmp(e,Allow[i])==0) {
           dejaLa(e); return 1;
        }
   }
   return 0;
}
int dejaDeny(char *e)
{
int i;
   for (i=0;i<iDen;i++) {
        if (strlen(e) != strlen(Deny[i])) continue;
        if (strcmp(e,Deny[i])==0) {
           dejaLa(e); return 1;
        }
   }
   return 0;
}

void recaplistes(void)
{
   listeDeny();
   listeAllow();
}

int litligne(char * line)
{
char *w, **S;
void * M;
int t;
      if (*line == '#') return 1;
      if ((w=strstr(line, "\n")) != NULL) *w = '\0';
      w=line;
      if (*w == '-') w++;
      t=strlen(w);
      if (t==0) return 1;
      if (isCidr(w)) { /* test si CIDR */
         addCidr(w);
         return 1;
      }
      if (*line == '-') {
         if (iDen == NBDen) return 0;
         if (dejaDeny(w)) return 0;
         S = &Deny[iDen];
         iDen++;
      } else {
         if (iAll == NBAll) return 0;
         if (dejaAllow(w)) return 0;
         S = &Allow[iAll];
         iAll++;
      }
      if ((M = malloc(t+1)) == NULL) {
         perror("malloc"); return 0;
      }
      *S=(char*)M;
      strcpy(*S,w);
      return 1;
}

void lectliste(char *f)
{
FILE * fd;
char *line = NULL;
size_t ll = 0;
int n;
   if ((fd = fopen(f,"r")) == NULL) {
     perror(f); return;
   }
   while ((n = getline(&line, &ll, fd)) > 0) {
      if (!litligne(line)) {
         if (T1) printf("T1: Erreur param. = %s\n",line);
      }
   }
   free(line);
   fclose(fd);
   validCidr();
   if (T1) listCidr();
}

/* ### gestion dynamique des elts */

#define NBT 1000  /* nb d'elts */
int Tno[NBT];
int Trv[NBT];
char* Turl[NBT];
int iT=0, NbElt=0, MaxElt=0;

int addElt(int n, char * u)
{
int i=iT;
  if (i == NBT) return i;
  Tno[i]=n;
  Trv[i]=0;
  Turl[i] = (char*)malloc(strlen(u)+1);
  strcpy(Turl[i],u);
  iT++;
  NbElt++;
  if (NbElt > MaxElt) MaxElt=NbElt;
  return i;
}

int isElt(int n)
{
int i;
  for (i=0; i<iT; i++) if (n==Tno[i]) return i;
  return -1;
}

void delIElt(int i)
{
   if (i>=iT) return;
   if (T3) printf("T3: Del %d : %s \n",Tno[i],Turl[i]);
   iT--;
   if (iT == i) return;
   if (iT > 0) {
      Tno[i] = Tno[iT];
      Turl[i] = Turl[iT];
      Trv[i] = Trv[iT];
   }
   return;
}
void delElt(int n)
{
int i;
  for (i=0; i<iT; i++)
     if (n==Tno[i]) {
        delIElt(i);
        return;
     }
}


int markElt(int i, int v)
{
  if (Trv[i] & v) return 0;
  Trv[i] |= v;
  return 1;
}

void listElt(char c)
{
int i,n=0;
  switch (c) {
    case '-':
      for (i=0; i<iT; i++)
          if (Tno[i]<0) { printf("%d : %s (%d)\n",Tno[i], Turl[i], Trv[i]);
             n++;
          }
      break;
    case '+':
      for (i=0; i<iT; i++)
          if (Tno[i]>0) { printf("%d : %s (%d)\n",Tno[i], Turl[i], Trv[i]);
             n++;
          }
      break;
    default:
      for (i=0; i<iT; i++) {
          printf("%d : %s (%d)\n",Tno[i], Turl[i], Trv[i]);
          n++;
      }
      break;
  }
  printf(" %d elements trouves.\n",n);
}



int comsh(char *com)
{
pid_t pid;
int ret;
   if ((pid = fork()) < 0) {
      perror("fork2"); return 99;
   }
   if (pid == 0) {
      signal(SIGINT,SIG_IGN);
      execl("/bin/sh", "sh", "-c", com, (char *) 0);
      perror("execl2"); return 98;
   }
   waitpid(pid,&ret,0);
   return WEXITSTATUS(ret);
}

int exeCom(char * comm) /* on se reserve le droit de modifier */
{
char b[120];
   sprintf(b,"%s >/dev/null 2>&1",comm);
   return comsh(b);
}

/* ### fct de MAJ iptables */
static char * IPT = "iptables";
static char * IP6T = "ip6tables";
static char * MYCH = "valide4";
static char * OUTP = "OUTPUT";
static char * MNO = "REJECT";
static char * MOK = "ACCEPT";

int initIPT(void)
{
int i=0;
char b[90];
   if (REPR) return 0;
   sprintf(b,"%s -F",IPT);
   i += exeCom(b);
   sprintf(b,"%s -F",IP6T);
   i += exeCom(b);
   sprintf(b,"%s -L %s -n",IPT,MYCH);
   if (exeCom(b)) {
      sprintf(b,"%s -N %s",IPT,MYCH);
      i += exeCom(b);
   }
   sprintf(b,"%s -A %s -j %s",IPT,OUTP,MYCH);
   i += exeCom(b);
   return i;
}

int isPresentIP(char * comm, char * ip, char * chain)
{
char buf[100];
   sprintf(buf,"%s -L %s -n|grep %s",comm,chain,ip);
   if (exeCom(buf) == 0) return 1;
   return 0;
}


int retireChain(char * comm, char * ip, char * chain, char * jump)
{
char buf[100];
   sprintf(buf,"%s -D %s -d %s -j %s",comm,chain, ip, jump);
   return exeCom(buf);
}

int ajouteChain(char * comm, char * ip, char * chain, char * jump)
{
char buf[100];
   sprintf(buf,"%s -A %s -d %s -j %s",comm,chain, ip, jump);
   return exeCom(buf);
}

int bloqueIP(char* ip)
{
   if (isAddrInCidr(ip,0)) return 0;
   if (isPresentIP(IPT,ip,OUTP)) return 0;
   return ajouteChain(IPT,ip,OUTP,MNO);
}

int debloqueIP(char* ip, char * url)
{
   if (url != NULL) syslog(LOG_INFO,"%s=%s ACCEPT",url,ip);
   return ajouteChain(IPT,ip,MYCH,MOK);
}

int rebloqueIP(char* ip)
{
   return retireChain(IPT,ip,MYCH,MOK);
}

void dropIP(char * l)
{
char *s,*d=l;
   while ((s=strstr(d, "A ")) != NULL) {
      s+=2;
      if ((d=strstr(s+2, ",")) == NULL) break;
      *d = '\0';
      d++;
      bloqueIP(s);
   }
   bloqueIP(s);
}

int verifIPOk(char * l, char * url)
{
char *s,*d=l;
   while ((s=strstr(d, "A ")) != NULL) {
      s+=2;
      if ((d=strstr(s+2, ",")) == NULL) break;
      *d = '\0';
      d++;
      if (isPresentIP(IPT,s,MYCH)) continue;
      if (isAddrInCidr(s,1)) debloqueIP(s,url);
   }
   if (isPresentIP(IPT,s,MYCH)) return 1;
   if (isAddrInCidr(s,1)) return(debloqueIP(s,url));
   return 1;
}

int dropIP6(char * l)
{
char *s,*d=l;
   while ((s=strstr(d, "A ")) != NULL) {
      s+=2;
      if ((d=strstr(s+2, ",")) == NULL) break;
      *d = '\0';
      d++;
      if (isPresentIP(IP6T,s,OUTP)) continue;
      ajouteChain(IP6T,s,OUTP,MNO);
   }
   if (isPresentIP(IP6T,s,OUTP)) return 1;
   ajouteChain(IP6T,s,OUTP,MNO);
   return 1;
}


/* tache de commande et periodiques */
#define t0 (time_t)0
time_t tim1=t0;
void tachePer1(void) /* vide les elts toutes les 30 secondes */
{
static time_t tim0=t0, tw;
int i, v;
   tw = time(NULL);
   if ((tw - tim0) < 30) {
      if (T3) printf ("T3: tache1 passe %s",ctime(&tw));
      return;
   }
   if (T3) printf ("T3: tache1 exec %s",ctime(&tw));
   tim1 = time(NULL);
   v = (tim1 - tim0) / 30;
   if (tim0 != t0) {
      for (i=iT-1; i>=0; i--) {
        if ((Trv[i]&0x6) == 6) delIElt(i); // IPv4 + IPV6
        else { Trv[i] += 8*v;
            if (Trv[i] > 80) delIElt(i); // On laisse 5 min.
        }
      }
   }
   tim0 = time(NULL);
   return;
}

void ajoutParam(char * ficp, char * param)
{
FILE * fw;
    fw = fopen(ficp,"a");
    fwrite(param,strlen(param),1,fw);
    fwrite("\n",1,1,fw);
    fclose(fw);
}

static int NBin=0, NBout=0;
void prInOut(void)
{
 printf(" %d messages DNS: %d requetes, %d reponses.\n",NBout+NBin,NBout,NBin);
}

int printQ(char * q)
{
char *rep=NULL;
size_t lr = 0;
int n;
   while (1) {
      printf("Voulez-vous %s ?\n Taper O (OUI) ou N (NON) :\n",q);
      if ((n = getline(&rep, &lr, stdin)) != 2) continue;
      if (*rep == 'O') return 1;
      if (*rep == 'N') return 0;
   }
}

void pr_encours(void)
{
   printf(" ...\r"); fflush(stdout);
}
 
#define SUNIC "|sort|uniq"
#define CHLOG "/var/log/user.log"
#define CHLOGREP "/var/log/user.log|grep "
#define CUT6 "|cut -d' ' -f6"
#define CUTM45 "|cut -d' ' -f1-3,6-"
#define CUT7S "|cut -d' ' -f7-"

#define FHISTO ".octave_history"
#define AWK5 "|awk '{ print $5}'"
#define AWK4 "|awk '{ print $4}'"
#define DREJ "^REJECT "
void * fct_com(void * p)
{
int REQ=1;
char *cmd = NULL, *fauth, com[100];
int n2;
pid_t pid;
  fauth = (char*)p;
  pid = getpid();
  read_history(FHISTO);
  if (REPR) comsh("reset");
  while (REQ) {
    if (kill(pid,SIGUSR1) < 0) { /* verif processus acquisition */
      ENDT=1;
      write(p1[1],"\n",1);
    }
    free(cmd);
    cmd = readline("O-> ");
    if ((n2 = strlen(cmd)) > 0) {
      write(p1[1],"\n",1);
      add_history(cmd);
      switch (*cmd) {
        case '+' :
          if (*(cmd+1) != '\0') {
            if (litligne(cmd+1)) { /* ajout au fichier fauth */
              if (debloqueIP(cmd+1,NULL)) printf("Element non valable !\n");
              else {
                if (printQ("ajouter au fichier parametres"))
                   ajoutParam(fauth,cmd+1);
                listeAllow();
              }
            } else printf("Erreur ajout param. !\n");
          } else listeAllow();
          break;
        case '-' :
          if (*(cmd+1) != '\0') {
            if (litligne(cmd)) { /* ajout au fichier fauth */
              if (rebloqueIP(cmd+1)) printf("Element non valable !\n");
              else {
                if (printQ("ajouter au fichier parametres"))
                   ajoutParam(fauth,cmd);
                listeDeny();
              }
            } else printf("Erreur ajout param. !\n");
          } else listeDeny();
          break;
        case 'l' :
          listElt(cmd[1]);
          printf(" %s Utilise %d elts/%d : %.2f%% (Max. %d)!\n",ctime(&tim1),iT,
               NBT, (float)(iT*100)/(float)NBT, MaxElt);
          prInOut();
          break;
        case 't' :
          if (*(cmd+1) != '\0') {
            if ((cmd[1] == '+') || (cmd[1] == '-')) {
              if ((cmd[1] == '+') && (Trace < TMAX)) Trace++;
              else {
                if ((cmd[1] == '-') && (Trace > TMIN)) Trace--;
                else printf("Erreur: niveau dans [%d, %d].\n",TMIN,TMAX);
              }
            } else printf("Erreur: Utiliser t+ ou t- !\n");
          }
          printf(" Trace niveau %d\n",Trace);
          break;
        case 'a' :
          if (*(cmd+1) != '\0') printf("ignore %s\n",cmd+1);
          sprintf(com,"grep '%s\\[%d\\]%s' %s%s%s",NPROG,pid,".* ok",
                                                   CHLOG,CUT6,SUNIC);
          comsh(com);
          break;
        case 'i' :
          if (*(cmd+1) != '\0') printf("ignore %s\n",cmd+1);
          sprintf(com,"grep '%s\\[%d\\]%s' %s%s%s",NPROG,pid,".* DENY",
                                                    CHLOG,CUT6,SUNIC);
          comsh(com);
          break;
        case 'e' :
          if (*(cmd+1) != '\0') printf("ignore %s\n",cmd+1);
          sprintf(com,"grep '%s\\[%d\\]%s' %s%s%s",NPROG,pid,".* ACCEPT",
                                                    CHLOG,CUT6,SUNIC);
          comsh(com);
          break;
        case 'E' :
          if (*(cmd+1) != '\0') printf("ignore %s\n",cmd+1);
          sprintf(com,"grep '%s\\[%d\\]%s' %s%s",NPROG,pid,".*ERR: ",
                                             CHLOG,CUTM45);
          comsh(com);
          break;
        case 'L' :
          if (*(cmd+1) != '\0') printf("ignore %s\n",cmd+1);
          sprintf(com,"grep '%s\\[%d\\]' %s%s%s",NPROG,pid,
                                             CHLOGREP,"-v 'Re[pq]. '",CUTM45);
          comsh(com);
          break;
        case 'T' :
          if (*(cmd+1) != '\0') { /* avec parametre */
             if ((*(cmd+1) == '+') && (*(cmd+2) != '\0')) { /* script + param */
                sprintf(com,"./t1.sh %d %s >.Trav%d",pid,cmd+2,pid);
                comsh(com);
                sprintf(com,"cat .Trav%d",pid);
             } else sprintf(com,"grep '%s\\[%d\\].*%s' %s%s%s",NPROG,pid,cmd+1,
                                             CHLOGREP," 'Re[pq]. '",CUTM45);
          } else
          sprintf(com,"grep '%s\\[%d\\]' %s%s%s",NPROG,pid,
                                             CHLOGREP," 'Re[pq]. '",CUTM45);
          comsh(com);
          prInOut();
          break;
        case '>' :
          if (*(cmd+1) != '\0') printf("ignore %s\n",cmd+1);
          sprintf(com,"grep '%s\\[%d\\]' %s%s%s%s",NPROG,pid,
                                             CHLOGREP," 'Req. '",CUT7S,SUNIC);
          comsh(com);
          prInOut();
          break;
        case '<' :
          if (*(cmd+1) != '\0') printf("ignore %s\n",cmd+1);
          sprintf(com,"grep '%s\\[%d\\]' %s%s%s%s",NPROG,pid,
                                             CHLOGREP," 'Rep. '",CUT7S,SUNIC);
          comsh(com);
          prInOut();
          break;
        case 'r' :
          if (*(cmd+1) != '\0') printf("ignore %s\n",cmd+1);
          sprintf(com,"%s -L|grep %s%s%s",IPT,DREJ,AWK5,SUNIC);
          pr_encours();
          comsh(com);
          break;
        case 'R' :
          if (*(cmd+1) != '\0') printf("ignore %s\n",cmd+1);
          sprintf(com,"%s -L|grep %s%s%s",IP6T,DREJ,AWK4,SUNIC);
          pr_encours();
          comsh(com);
          break;
        case 'S' :
          if (*(cmd+1) != '\0') printf("ignore %s\n",cmd+1);
          RUN = 0;
          REQ = 0;
          write(p1[1],"\n",1);
          break;
        case 'V' :
          if (*(cmd+1) != '\0') printf("ignore %s\n",cmd+1);
          printf("Version %s\n",Version);
          prInOut();
          break;
        case ' ' :
          if (*(cmd+1) != '\0') comsh(cmd+1);
          break;
        default :
          printf("+url\t: Allow (autoriser une Url)\n");
          printf("-url\t: Deny (interdire une Url)\n");
          printf("a\t: Autorisations suivant analyse\n");
          printf("i\t: Interdictions suivant analyse\n");
          printf("e\t: Exceptions suivant analyse\n");
          printf("E\t: Liste des erreurs\n");
          printf("l[+|-]\t: Liste des elements dynamiques\n");
          printf("L\t: Logs du systeme\n");
          printf("r\t: Rejets actifs IPv4 (dure plusieurs sec.)\n");
          printf("R\t: Rejets actifs IPv6 (dure plusieurs sec.)\n");
          printf("S\t: Stopper\n");
          printf("t+|-\t: Niveau de trace : 0 (off) => 3\n");
          printf("T[mot]\t: Traces des demandes/reponses contenant mot\n");
          printf(">\t: Traces des demandes triees\n");
          printf("<\t: Traces des reponses triees\n");
          printf("V\t: Version\n");
          break;
      }
    }
  }
  write_history(FHISTO);
  free(cmd);
  /* fin dialogue */
  pthread_exit(NULL);
}

void getIface(void)
{
FILE * fd;
char *line = NULL, *s, *w;
size_t ll = 0;
int n;
   if ((fd = fopen("/proc/net/route","r")) == NULL) {
        perror("route"); return;
   }
   while ((n = getline(&line, &ll, fd)) > 0) {
      if ((s=strstr(line,"00000000"))==NULL) continue;
      w=line;
      while ((*w != ' ') && (*w != '\t')) w++;
      *w = '\0';
      w++;
      while ((*w == ' ') || (*w == '\t')) w++;
      if (s==w) { /* ok */
         IFACE = (char*)malloc(strlen(line)+1);
         strcpy(IFACE,line);
         break;
      }
   }
   free(line);
   fclose(fd);
}

#define Vie (ie >= 0)
int main(int N, char * P[])
{
pthread_t thid;
FILE * fp;
char *analyse="tcpdump", *line = NULL, *cmd = NULL, *s1, *s2, *refU;
char *fauth = "auth1.txt", *strR = "-R", *Pars, strPID[8], **NP;
size_t ll = 0, lc = 0;
ssize_t n,n2;
int Inter=0, LogC=0, i, ie, np=0, opt;
   if ((NPROG = strrchr(P[0],(int)'/')) == NULL) NPROG=P[0];
   else NPROG++;
   sprintf(strPID,"%d",getpid());
   /* verif. options */
   while ((opt = getopt(N, P, "ilp:R:t")) != -1) {
       switch (opt) {
          case 'i':
              Inter = 1;
              break;
          case 'l':
              LogC = 1;
              break;
          case 't':
              Trace = TMIN+1;
              break;
          case 'p':
              fauth = optarg;
              break;
          case 'R':
              REPR=1;
              np = atoi(optarg);
              break;
          default: /* '?' */
              fprintf(stderr, "Utilisation: %s [options]\nAvec les options :\n", NPROG);
              fprintf(stderr, "\t-i         : mode interactif,\n");
              fprintf(stderr, "\t-l         : log des requetes,\n");
              fprintf(stderr, "\t-p fichier : nom du fichier parametres (%s par defaut),\n",fauth);
              fprintf(stderr, "\t-t         : avec trace.\n");
              return 1;
       }
   }
   if ((REPR) && (np != getpid())) {
      fprintf(stderr,"Erreur reprise %d\n", np);
      return 1;
   }
   if (optind < N) {
      fprintf(stderr,"Parametre inconnu : %s\n", P[optind]);
      return 1;
   }
   getIface();
   if (REPR) {
      while (IFACE==NULL) { sleep(1); getIface(); }
   } else {
      if (IFACE == NULL) {
         fprintf(stderr,"Interface reseau absente !\n");
         return 9;
      }
   }
   printf("%s %s sur %s\n", NPROG, Version, IFACE);
   /* verif privilege root */
   if ((getuid() > 0) && (geteuid() > 0)) {
      fprintf(stderr,"A executer sous root !\n");
      return 2;
   }
   if (T1) printf("T1: Fichier parametres = %s\n",fauth);
   signal(SIGUSR1,SIG_IGN);
   if (pipe(p1) < 0) {
      perror("pipe"); return 3;
   }
   openlog(NULL,LOG_PID,0);
   /* on lance le fils : */
   if ((pid = fork()) < 0) {
      perror("fork"); return 4;
   }
   if (pid == 0) {
      signal(SIGINT,SIG_IGN);
      close(0);
      close(p1[0]);
      dup2(p1[1],1); /* stdout dans p1 */
      dup2(p1[1],2); /* idem stderr */
      setsid();
      execlp(analyse,analyse,"-tn","-i",IFACE,"port","53",NULL);
      perror("execl");
      return 5;
   }
   if (Inter) signal(SIGINT,SIG_IGN);
   else       signal(SIGINT,interup);
   if ((np=initIPT())!=0) {
      if (T1) printf("Erreur initIPT %d !!??\n",np);
      syslog(LOG_WARNING, "ERR: Erreur initIPT %d !!??\n",np);
   }
   /* lecture des listes */
   lectliste(fauth);
   if (T1) recaplistes();
   sleep(1); /* attend le fils en place */
   if (kill(pid,SIGUSR1) < 0) return 6;
   signal(SIGCHLD,interup);
/*
   fcntl(p1[0], F_SETFL, O_NONBLOCK); 
   flag0 = fcntl(0, F_GETFL, O_NONBLOCK); 
   fcntl(0, F_SETFL, O_NONBLOCK); 
*/
   /* on analyse la sortie de p1 */
   if ((fp = fdopen(p1[0],"r")) == NULL) {
      perror("fdopen"); return 7;
   }
   fcntl(p1[0], F_SETPIPE_SZ,1048576);
   if (T1) printf("Depart %s %s PIDF:%d !\n",NPROG, strPID,pid);
   if (T1) printf("Capacite pipe : %ld bytes\n", (long)fcntl(p1[0], F_GETPIPE_SZ));
   np=0;
   /* lancement du thread */
   if (Inter) {
      if (pthread_create(&thid,NULL,fct_com,(void*)fauth) != 0) {
         fprintf(stderr,"Erreur pthread_create !\n"); return 9;
      }
   }
   while (RUN) {
      tachePer1();
      if ((n = getline(&line, &ll, fp)) > 0) {
         if (ENDT) {
            printf("Erreur : plus de tache d'analyse !\n"); break;
         }
         if (RUN == 0) break;
         if ((n==1) && (*line=='\n')) continue;
         if (np==0) { np++;
            if (REPR) syslog(LOG_INFO,"Reprise de l'analyse !");
            else syslog(LOG_INFO,"Debut de l'analyse !");
         }
         /* analyse */
         if ((s1=strstr(line, " > ")) == NULL) continue;
         if (strncmp(s1-3,".53",3) == 0) { /* REPONSE */
           if ((s2=strstr(s1+3, ":")) == NULL) continue;
           NBin++;
           *s2 = '\0';
           s1 = s2 -1;
           while (*s1 != '.') s1--;
           np = atoi(s1+1);
           if ((ie = isElt(np)) == -1) { /* Elt OK ou ABSENT ! */
              ie = isElt(-np);
              s1 = s2+1;
              if ((s2=strstr(s1, " A ")) != NULL) { /* IPv4 */
                 s2++;
                 s1 = strrchr(s2,(int)' ');
                 *s1 = '\0';
                 if (LogC) syslog(LOG_INFO,"Rep. %d %s",np,s2);
                 if Vie {
                    markElt(ie,4); refU = Turl[ie];
                 } else {
                    if (T1) printf("Elt %d non trouve !!??\n",np);
                    syslog(LOG_WARNING,"ERR: Elt %d non trouve !!??\n",np);
                    refU = NULL;
                 }
                 if (!verifIPOk(s2, refU))
                    if Vie syslog(LOG_INFO,"Deblocage IP4 %s",refU);
              } else {
                 if ((s2=strstr(s1, " AAAA ")) != NULL) { /* IPv6 */
                    s2++;
                    s1 = strrchr(s2,(int)' ');
                    *s1 = '\0';
                    if (LogC) syslog(LOG_INFO,"Rep. %d %s",np,s2);
                    if Vie markElt(ie,2);
                    dropIP6(s2);
                 } else {
                    if Vie markElt(ie,1);
                 }
              }
              continue;
           }
           s1 = s2+1;
           if ((s2=strstr(s1, " A ")) == NULL) {
              if ((s2=strstr(s1, " AAAA ")) == NULL) {
                 markElt(ie,1);
              } else { /* traitement IPv6 */
                 s2++;
                 if (LogC) syslog(LOG_INFO,"Rep. %d %s",np,s2);
                 s1 = strrchr(s2,(int)' ');
                 *s1 = '\0';
                 if (markElt(ie,2)) dropIP6(s2);
              }
              continue;
           }
           /* IPv4 REJECT */
           s2++;
           s1 = strrchr(s2,(int)' ');
           *s1 = '\0';
           if (LogC) syslog(LOG_INFO,"Rep. %d %s",np,s2);
           syslog(LOG_INFO,"%s DENY",Turl[ie]);
           if (markElt(ie,4)) dropIP(s2);
         } else { /* DEMANDE */
           NBout++;
           *s1 = '\0';
           s2 = s1 +1;
           while (*s1 != '.') s1--;
           np = atoi(s1+1);
           if ((s1=strstr(s2, " A? ")) == NULL) continue;
           s1 += 4;
           s2 = s1 +1;
           while (*s2 != ' ') s2++;
           *(s2-1) = '\0'; /* on supprime le '.' */
           if (LogC) syslog(LOG_INFO,"Req. %d %s",np,s1);
           if (strstr(s1, ".") == NULL) { /* il doit en rester 1 */
                 if (T1) printf("Ignore : %d %s !\n",np,s1);
                 syslog(LOG_WARNING,"ERR: Ignore %d %s !\n",np,s1);
                 continue;
           }
           if (!isDeny(s1)) { // V2 ! On enregistre le OK en NEGATIF
              if (isElt(-np) < 0) {
                 addElt(-np,s1);
                 syslog(LOG_INFO,"%s ok",s1);
              }
              continue;
           }
           if (isElt(np) < 0) {
              i=addElt(np,s1);
              if (T3) printf("T3: addElt %d %d/%d\n",NbElt,i,NBT);
           }
         }
      }
      if (REQ) {
         printf("Taper votre commande : H pour help !\n");
         if ((n2 = getline(&cmd, &lc, stdin)) > 0) {
            switch (*cmd) {
               case 'C' :
                  REQ = 0;
                  break;
               case 'L' :
                  listElt(cmd[1]);
                  printf(" %s Utilise %d elts/%d : %.2f%% (Max. %d)!\n",
                       ctime(&tim1),iT,NBT,(float)(iT*100)/(float)NBT,MaxElt);
                  break;
               case 'S' :
                  RUN = 0;
                  REQ = 0;
                  break;
               default :
                  printf("C\t: continuer\n");
                  printf("L\t: liste des elts\n");
                  printf("S\t: stopper\n");
                  break;
            }
         }
      }
   }
   syslog(LOG_INFO,"Fin de l'analyse !");
   free(line);
   free(cmd);
   kill(pid,SIGTERM);
   close(p1[0]);
   close(p1[1]);
   closelog();
   if (ENDT) { /* relance auto */
       comsh("reset");
       if (T1) printf("Relance auto %s dans %d sec. ...\n",strPID, DELAYR);
       sleep(DELAYR); /* attend N s */
       NP = (char**)malloc((sizeof(Pars))*(N+3));
       for (i=0;i<N;i++) NP[i] = P[i];
       NP[i++]=strR; 
       NP[i++]=strPID; 
       NP[i]=NULL; 
       execv(P[0],NP);
       perror("execv");
   }
   printf("Fin du programme!\n");
   return 0;
}