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|
*** ftp-gw.c.orig Sun Jun 22 16:27:42 1997
--- ftp-gw.c Sun Jun 22 17:02:16 1997
***************
*** 11,31 ****
--- 11,41 ----
*/
static char RcsId[] = "$Header: /devel/CVS/IP-Filter/FWTK/ftp-gw.diff,v 2.1 1999/08/04 17:30:30 darrenr Exp $";
+ /*
+ * Patches for IP Filter NAT extensions written by Darren Reed, 7/7/96
+ * darrenr@cyber.com.au
+ */
+ static char vIpFilter[] = "v3.1.11";
#include <stdio.h>
#include <ctype.h>
#include <syslog.h>
+ #include <unistd.h>
+ #include <fcntl.h>
#include <sys/signal.h>
#include <sys/ioctl.h>
#include <sys/errno.h>
extern int errno;
+ #ifdef sun
extern char *sys_errlist[];
+ #endif
#include <arpa/ftp.h>
#include <arpa/telnet.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
+ #include <net/if.h>
extern char *rindex();
extern char *index();
***************
*** 36,41 ****
--- 46,54 ----
#include "firewall.h"
+ #include "ip_compat.h"
+ #include "ip_fil.h"
+ #include "ip_nat.h"
#ifndef BSIZ
#define BSIZ 2048
***************
*** 83,88 ****
--- 96,103 ----
static int cmd_noop();
static int cmd_abor();
static int cmd_passthru();
+ static int nat_destination();
+ static int connectdest();
static void saveline();
static void flushsaved();
static void trap_sigurg();
***************
*** 317,323 ****
if(authallflg)
if(say(0,"220-Proxy first requires authentication"))
exit(1);
! sprintf(xuf,"220 %s FTP proxy (Version %s) ready.",huf,FWTK_VERSION_MINOR);
if(say(0,xuf))
exit(1);
}
--- 332,341 ----
if(authallflg)
if(say(0,"220-Proxy first requires authentication"))
exit(1);
! sprintf(xuf,"220-%s FTP proxy (Version %s) ready.",huf,FWTK_VERSION_MINOR);
! if(say(0,xuf))
! exit(1);
! sprintf(xuf,"220-%s TIS ftp-gw with IP Filter %s NAT extensions",huf,vIpFilter);
if(say(0,xuf))
exit(1);
}
***************
*** 338,343 ****
--- 356,363 ----
exit(1);
}
+ nat_destination(0);
+
/* main loop */
while(1) {
FD_ZERO(&rdy);
***************
*** 608,619 ****
static char narg[] = "501 Missing or extra username";
static char noad[] = "501 Use user@site to connect via proxy";
char buf[1024];
- char mbuf[512];
char *p;
char *dest;
char *user;
int x;
- int msg_int;
short port = FTPPORT;
/* kludgy but effective. if authorizing everything call auth instead */
--- 628,637 ----
***************
*** 643,648 ****
--- 661,687 ----
return(sayn(0,noad,sizeof(noad)));
}
+ if((rfd == -1) && (x = connectdest(dest,port)))
+ return x;
+ sprintf(buf,"USER %s",user);
+ if(say(rfd,buf))
+ return(1);
+ x = getresp(rfd,buf,sizeof(buf),1);
+ if(sendsaved(0,x))
+ return(1);
+ return(say(0,buf));
+ }
+
+ static int
+ connectdest(dest,port)
+ char *dest;
+ short port;
+ {
+ char buf[1024];
+ char mbuf[512];
+ int msg_int;
+ int x;
+
if(*dest == '\0')
dest = "localhost";
***************
*** 685,693 ****
char ebuf[512];
strcpy(ebuf,buf);
! sprintf(buf,"521 %s: %s",dest,ebuf);
return(say(0,buf));
}
sprintf(buf,"----GATEWAY CONNECTED TO %s----",dest);
saveline(buf);
--- 724,733 ----
char ebuf[512];
strcpy(ebuf,buf);
! sprintf(buf,"521 %s,%d: %s",dest,ntohs(port),ebuf);
return(say(0,buf));
}
+
sprintf(buf,"----GATEWAY CONNECTED TO %s----",dest);
saveline(buf);
***************
*** 698,711 ****
return(say(0,buf));
}
saveline(buf);
!
! sprintf(buf,"USER %s",user);
! if(say(rfd,buf))
! return(1);
! x = getresp(rfd,buf,sizeof(buf),1);
! if(sendsaved(0,x))
! return(1);
! return(say(0,buf));
}
--- 738,745 ----
return(say(0,buf));
}
saveline(buf);
! sendsaved(0,-1);
! return 0;
}
***************
*** 1591,1593 ****
--- 1625,1671 ----
dup(nread);
}
#endif
+
+
+ static int
+ nat_destination(fd)
+ int fd;
+ {
+ struct sockaddr_in laddr, faddr;
+ struct natlookup natlookup;
+ char *dest;
+ int slen, natfd;
+
+ bzero((char *)&laddr, sizeof(laddr));
+ bzero((char *)&faddr, sizeof(faddr));
+ slen = sizeof(laddr);
+ if(getsockname(fd,(struct sockaddr *)&laddr,&slen) < 0) {
+ perror("getsockname");
+ exit(1);
+ }
+ slen = sizeof(faddr);
+ if(getpeername(fd,(struct sockaddr *)&faddr,&slen) < 0) {
+ perror("getsockname");
+ exit(1);
+ }
+
+ natlookup.nl_inport = laddr.sin_port;
+ natlookup.nl_outport = faddr.sin_port;
+ natlookup.nl_inip = laddr.sin_addr;
+ natlookup.nl_outip = faddr.sin_addr;
+ natlookup.nl_flags = IPN_TCP;
+ if((natfd = open(IPL_NAT, O_RDONLY)) < 0) {
+ perror("open");
+ exit(1);
+ }
+ if(ioctl(natfd, SIOCGNATL, &natlookup) == -1) {
+ syslog(LOG_ERR, "SIOCGNATL failed: %m\n");
+ close(natfd);
+ if(say(0,"220 Ready"))
+ exit(1);
+ return 0;
+ }
+ close(natfd);
+ return connectdest(inet_ntoa(natlookup.nl_realip),
+ ntohs(natlookup.nl_realport));
+ }
|
