misc/archive/xctrld.c

   1 /*
   2  * gcc -Wall -O2 xctrld.c -o /sbin/xctrld
   3  *
   4  * --- T2-COPYRIGHT-NOTE-BEGIN ---
   5  * This copyright note is auto-generated by ./scripts/Create-CopyPatch.
   6  *
   7  * T2 SDE: misc/archive/xctrld.c
   8  * Copyright (C) 2004 - 2005 The T2 SDE Project
   9  * Copyright (C) 1998 - 2003 ROCK Linux Project
  10  *
  11  * More information can be found in the files COPYING and README.
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; version 2 of the License. A copy of the
  16  * GNU General Public License can be found in the file COPYING.
  17  * --- T2-COPYRIGHT-NOTE-END ---
  18  */
  19
  20 #include <fcntl.h>
  21 #include <netinet/in.h>
  22 #include <signal.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <sys/socket.h>
  27 #include <sys/stat.h>
  28 #include <sys/time.h>
  29 #include <sys/types.h>
  30 #include <sys/wait.h>
  31 #include <unistd.h>
  32 #include <errno.h>
  33
  34 #define PORT 2225
  35
  36 #define BUFSIZE 1024
  37
  38 FILE * out = NULL;
  39
  40 #define xprf(format, args... ) fprintf(out,"Cliffords Control-Daemon: " format "\r", ## args)
  41
  42 /*  This function is very dirty - but it seams to to the only way that
  43  *  works without using pty devices. making the netfd directly the stdin
  44  *  stdout and stderr channels of /bin/sh caused a lot of problems ...
  45  */
  46 void do_session(int netfd) {
  47         int p_in[2],p_out[2];
  48         int rc,maxfd,pid,c;
  49         struct timeval tv;
  50         char buf[BUFSIZE];
  51         fd_set rfds;
  52
  53         snprintf(buf,BUFSIZE,"\n"
  54 "Hello! This is a mini telnet daemon which is not using a pty device.\n"
  55 "So you wont have job control or other things where ptys are needed.\n"
  56 "\nThis session has the PID %d. Have fun.\n\n",(int)getpid());
  57         write(netfd,buf,strlen(buf));
  58
  59         pipe(p_in); pipe(p_out);
  60         if (signal(SIGCHLD,SIG_DFL) == SIG_ERR) xprf("signal: %s",strerror(errno));
  61
  62         if ( (pid=fork()) == 0 ) {
  63                 close(0); dup2(p_in[0],0);
  64                 close(1); dup2(p_out[1],1);
  65                 close(2); dup2(p_out[1],2);
  66                 close(p_in[0]);  close(p_in[1]);
  67                 close(p_out[0]); close(p_out[1]); close(netfd);
  68                 setenv("USER","root",1);    setenv("HOME","/root",1);
  69                 setenv("LOGNAME","root",1); setenv("TERM","linux",1);
  70                 execl("/bin/sh","/bin/sh","--login","-i",NULL);
  71                 xprf("execl: %s",strerror(errno)); exit(1);
  72         }
  73
  74         close(p_in[0]); close(p_out[1]);
  75
  76         while (waitpid(pid,NULL,WNOHANG) != pid) {
  77                 FD_ZERO(&rfds); FD_SET(netfd,&rfds); FD_SET(p_out[0],&rfds);
  78                 maxfd = netfd>p_out[0] ? netfd : p_out[0];
  79                 tv.tv_sec=1; tv.tv_usec=0;
  80                 rc=select(maxfd+1, &rfds, NULL, NULL, NULL);
  81                 if (rc == -1) { xprf("select: %s",strerror(errno)); return; }
  82                 if (FD_ISSET(netfd, &rfds)) {
  83                         rc=read(netfd,buf,BUFSIZE);
  84                         for (c=0; c<rc; c++)
  85                                 if (buf[c]!='\r') write(p_in[1],buf+c,1);
  86                 }
  87                 if (FD_ISSET(p_out[0], &rfds)) {
  88                         rc=read(p_out[0],buf,BUFSIZE);
  89                         for (c=0; c<rc; c+=write(netfd,buf,rc)) ;
  90                 }
  91         }
  92 }
  93
  94 int main(int argc, char ** argv) {
  95         struct sockaddr_in addr;
  96         int listenfd,fd;
  97
  98         if (argc != 2 || argv[1][0] == '-') {
  99                 fprintf(stderr,"Usage: %s < log-file | tty-device >\n",argv[0]);
 100                 return 1;
 101         }
 102
 103         if ( (out=fopen(argv[1],"a+")) == NULL ) {
 104                 fprintf(stderr,"Can't open log file '%s': %s",argv[1],strerror(errno));
 105                 return 1;
 106         }
 107         setvbuf(out,NULL,_IONBF,0);
 108         chdir("/");
 109
 110         printf("Cliffords Remote Control Daemon starting in 3 seconds ...\n");
 111         if (fork()) return 0;
 112         sleep(3);
 113
 114         fprintf(out,"\n\n\r");
 115         xprf("Binding port %d and waiting for connections ...\n",PORT);
 116         if (signal(SIGCHLD,SIG_IGN) == SIG_ERR) xprf("signal: %s",strerror(errno));
 117
 118         if ((listenfd=socket(AF_INET,SOCK_STREAM,0)) == -1) xprf("socket: %s",strerror(errno));
 119
 120         bzero(&addr,sizeof(addr));
 121         addr.sin_family=AF_INET;
 122         addr.sin_addr.s_addr = htonl(INADDR_ANY);
 123         addr.sin_port = htons(PORT);
 124
 125         if (bind(listenfd,&addr,sizeof(addr)) == -1) xprf("bind: %s",strerror(errno));
 126
 127         if (listen(listenfd,5)==-1) xprf("listen: %s",strerror(errno));
 128
 129         while (1) {
 130                 if ((fd=accept(listenfd,NULL,NULL)) == -1) xprf("accept: %s",strerror(errno));
 131                 if (!fork()) {
 132                         xprf("connection %d opened.\n",(int)getpid());
 133                         do_session(fd);
 134                         xprf("connection %d closed.\n",(int)getpid());
 135                         return 0;
 136                 } else close(fd);
 137         }
 138         return 0;
 139 }