Source Code 1992 March/Source_Code_CD-ROM_Walnut_Creek_March_1992.iso/usenet/altsrcs/3/3543/tcpclient.c

C/C++ Source or Header | 1991-06-26 | 4.9 KB | 200 lines

/* Public domain. */

#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/param.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <signal.h>
#include "dupdup.h"
#include "malloc.h"
#include "errno.h"
#include "username.h"
#include "hostname.h"
#include "portname.h"
#include "env.h"
#include "getopt.h"
#include "authuser.h"
#include "numfiles.h"

#ifndef MAXHOSTNAMELEN
#define MAXHOSTNAMELEN 64
#endif

static int flagdo931 = 1;
static int flagverbose = 1;
static struct sockaddr_in sa;
static struct sockaddr_in saloc;

static char errbuf[500];
void die(n,s) int n; char *s;
{ if (flagverbose) fprintf(stderr,"tcpclient: fatal: %s\n",s); exit(n); }
void dies(n,s,t) int n; char *s; char *t;
{ if (flagverbose) fprintf(stderr,"tcpclient: fatal: %s%s\n",s,t); exit(n); }
void diep(n,s) int n; char *s;
{ if (flagverbose) sprintf(errbuf,"tcpclient: fatal: %s",s); perror(errbuf); exit(n); }
void warnp(s) char *s;
{ if (flagverbose) sprintf(errbuf,"tcpclient: warning: %s",s); perror(errbuf); }
void warnsp(s,t) char *s; char *t;
{ if (flagverbose) sprintf(errbuf,"tcpclient: warning: %s%s",s,t); perror(errbuf); }

main(argc,argv,envp)
int argc;
char *argv[];
char *envp[];
{
 int t;
 int *d;
 int tdup;
 int numfiles;
 int i;
 static char tcplocal[200];
 static char tcpremote[300];
 int opt;
 int uid;
 char *uname;
 char lochost[MAXHOSTNAMELEN];
 struct in_addr locinaddr;
 int port;
 int locport;
 int dummy;
 char *ruser;

 locport = 0;

 while ((opt = getopt(argc,argv,"qQp:rR")) != EOF)
   switch(opt)
    {
     case 'q':
       flagverbose = 0; break;
     case 'Q':
       flagverbose = 1; break;
     case 'p':
       /* XXX: check that optarg is numeric? */
       locport = atoi(optarg);
       break;
     case 'r':
       flagdo931 = 1;
       break;
     case 'R':
       flagdo931 = 0;
       break;
     case '?':
       break; /*XXX*/
     default:
       break; /*XXX*/
    }
 argc -= optind; argv += optind;

 if (argc < 3)
   die(1,"need at least three arguments");

 uid = getuid();
 if (uid2username(uid,&uname) == -1) /* will never happen */
   die(2,"cannot figure out my own username");

 gethostname(lochost,sizeof(lochost));
 if (hostname2inaddr(lochost,&locinaddr) == -1)
   die(2,"cannot figure out my own hostname");

 if ((argv[0][0] == '0') && (argv[0][1] == 0))
   sa.sin_addr.s_addr = INADDR_ANY; /* special case "0" */
 else
  {
   if (hostname2inaddr(argv[0],&sa.sin_addr) == -1)
     dies(2,"cannot figure out hostname ",argv[0]);
  }

 if (portname2port(argv[1],&port,"tcp") == -1)
   dies(2,"cannot figure out portname ",argv[1]);
 port = port & 65535;
 sa.sin_port = htons((short) port);

 close(6);
 close(7); /* XXX: these have implications that should be documented */

 signal(SIGPIPE,SIG_IGN);

 numfiles = NUMFILES;
 d = (int *) malloc(numfiles * sizeof(int));
 if (!d)
   die(6,"cannot malloc");
 for (i = 0;i < numfiles;++i)
   d[i] = -1;

 if (env_init() == -1)
   die(11,"cannot init environment");
 if (env_put("PROTO=TCP") == -1)
   die(11,"out of memory putting PROTO into environment");

 t = socket(AF_INET,SOCK_STREAM,0);
 if (t == -1)
   diep(7,"cannot create client socket");
 sa.sin_family = AF_INET;
 if (locport)
  {
   /* attempt to bind to given local port */
   /* could do this in advance in all cases if we were desperate to
      get TCPLOCAL figured out as fast as possible */
   saloc.sin_family = AF_INET;
   saloc.sin_addr.s_addr = INADDR_ANY;
   saloc.sin_port = htons((short) locport);
   if (bind(t,&saloc,sizeof(saloc)) == -1)
     diep(9,"cannot bind to local port");
  }
 if (connect(t,&sa,sizeof(sa)) == -1)
   /* XXX: HRRFC says we should try alternate addresses */
   diep(9,"cannot connect to server");
 dummy = sizeof(saloc);
 if (getsockname(t,&saloc,&dummy) == -1)
   diep(9,"cannot figure out local connection address");

 locport = ntohs(saloc.sin_port);

 ruser = "";
 if (flagdo931)
  {
   ruser = auth_tcpuser((unsigned long) sa.sin_addr.s_addr
      ,(unsigned short) locport
      ,(unsigned short) port);
   if (!ruser)
     ruser = ""; /* XXX: any other suggestions? */
  }

 sprintf(tcplocal,"TCPLOCAL=%s@%s(%s):%d"
   ,uname
   ,inet_ntoa(locinaddr) /* could use saloc.sin_addr */
   ,lochost /* could use hostname of saloc.sin_addr */
   ,locport
  );
 if (env_put(tcplocal) == -1)
   die(11,"out of memory putting TCPLOCAL into environment");
 sprintf(tcpremote,"TCPREMOTE=%s@%s(%s):%d"
   ,ruser
   ,inet_ntoa(sa.sin_addr)
   ,argv[0] /* could do lookup instead, but why bother? */
   ,port
  );
 if (env_put(tcpremote) == -1)
   die(11,"out of memory putting TCPREMOTE into environment");

 /* XXX: fork? not necessary here */

 tdup = dup(t);
 if (tdup == -1)
   diep(10,"cannot dup connection to server");

 /* Now put t into descriptor 6 and tdup into descriptor 7. */
 /* XXX: should check that t and tdup are small enough */
 d[t] = 6;
 d[tdup] = 7;
 if (dupdup(d,numfiles) == -1)
   diep(10,"cannot dup connection to server");

 signal(SIGPIPE,SIG_DFL);
 execvp(argv[2],argv + 2);
 warnsp("cannot exec ",argv[2]);
 exit(1);
}