/* * Copyright 1989 by Georgia Tech Research Corporation, Atlanta, GA. * Copyright 1988, 1989 by Robert Viduya. * Copyright 1990 Jeff Sparkes. * * All Rights Reserved * * Updated 03/1993 George Haddad Michigan State U.(georgeh@ibm.cl.msu.edu): * Remove exit() calls ... always return to caller * * Updated 04/1993 George Haddad Michigan State U.(georgeh@ibm.cl.msu.edu): * Apply patchlevel 01 (thanks to David W. Sanderson) * */ /* * telnet.c * This module initializes and manages a telnet socket to * the given IBM host. */ #include #include #ifdef sun #include #endif #include #include #ifndef hpux #include #else #include "telnet.h" #endif #include #include #include #include #define BUFSZ 4096 #define FALSE 0 #define TRUE 1 u_char myopts[256], hisopts[256]; /* telnet option flags */ u_char ibuf[4*BUFSZ], *ibptr; /* 3270 input buffer */ u_char obuf[4*BUFSZ], *obptr; /* 3270 output buffer */ u_char netrbuf[BUFSZ]; /* network input buffer */ u_char sbbuf[1024], *sbptr; /* telnet sub-option buffer */ extern int model_num; /* 3270 model number */ extern int session_active; /* set FALSE to terminate*/ /* telnet states */ #define TNS_DATA 0 /* receiving data */ #define TNS_IAC 1 /* got an IAC */ #define TNS_WILL 2 /* got an IAC WILL */ #define TNS_WONT 3 /* got an IAC WONT */ #define TNS_DO 4 /* got an IAC DO */ #define TNS_DONT 5 /* got an IAC DONT */ #define TNS_SB 6 /* got an IAC SB */ #define TNS_SB_IAC 7 /* got an IAC after an IAC SB */ static u_char telnet_state; /* telnet predefined messages */ static u_char do_opt[] = { IAC, DO, '_' }; static u_char dont_opt[] = { IAC, DONT, '_' }; static u_char will_opt[] = { IAC, WILL, '_' }; static u_char wont_opt[] = { IAC, WONT, '_' }; static u_char ttype_opt[] = { IAC, SB, TELOPT_TTYPE, TELQUAL_IS, 'I', 'B', 'M', '-', '3', '2', '7', '8', '-', '4', IAC, SE }; extern u_long inet_addr (); extern int retcode; /* return code */ /* * connect_net * Establish a telnet socket to the given host passed as an argument. * Called only once and is responsible for setting up the telnet * variables. Returns the file descriptor of the connected socket. */ int connect_net (host, portname) char *host; char *portname; { struct servent *sp; struct hostent *hp; struct sockaddr_in sin; int net, i; int errnet = -1; /* initialize the telnet variables */ bzero ((char *) myopts, sizeof (myopts)); bzero ((char *) hisopts, sizeof (hisopts)); telnet_state = TNS_DATA; ibptr = &ibuf[0]; sbptr = &sbbuf[0]; /* get the tcp/ip service (telnet) */ if ((sp = getservbyname (portname, "tcp")) == (struct servent *) 0) { (void) fprintf (stderr, "x3270: %s/tcp - unknown service\n", portname); return (errnet); } /* fill in the socket address of the given host */ bzero ((char *) &sin, sizeof (sin)); if ((hp = gethostbyname (host)) == (struct hostent *) 0) { sin.sin_family = AF_INET; sin.sin_addr.s_addr = inet_addr (host); if (sin.sin_addr.s_addr == -1) { (void) fprintf (stderr, "x3270: unknown host (%s)\n", host); return (errnet); } } else { sin.sin_family = hp->h_addrtype; bcopy ((char *) hp->h_addr, (char *) &sin.sin_addr, hp->h_length); } sin.sin_port = sp->s_port; /* create and establish a connection on the socket */ if ((net = socket (AF_INET, SOCK_STREAM, 0)) == -1) { perror ("x3270: socket"); return (errnet); } if (connect (net, (struct sockaddr *) &sin, sizeof (sin)) == -1) { perror ("x3270: connect"); return (errnet); } /* set the socket to be asynchronous and non-delaying */ #if 0 #ifndef hpux i = FNDELAY | FASYNC; if (fcntl (net, F_SETFL, i) == -1) { perror ("x3270: fcntl"); return (errnet); } #else /* hpux */ i = O_NDELAY; if (fcntl (net, F_SETFL, i) == -1) { perror ("x3270: fcntl"); return (errnet); } i = 1; if (ioctl (net, FIOASYNC, (char *)&i) == -1) { perror ("x3270: fcntl"); return (errnet); } #endif /* hpux */ #endif i = -getpid (); #ifndef SOLARIS if (ioctl (net, SIOCSPGRP, &i) == -1) { perror ("x3270: ioctl"); return (errnet); } #endif /* all done */ return (net); } /* * net_input * Called by the notifier whenever there is input available on the * socket. Reads the data, processes the special telnet commands * and calls net_process to process the 3270 data stream. */ /*ARGSUSED*/ net_input (fd) int fd; { register u_char *cp; int nr; nr = read (fd, (char *) netrbuf, BUFSZ); if (nr > 0) { for (cp = netrbuf; cp < (netrbuf + nr); cp++) { switch (telnet_state) { case TNS_DATA: /* normal data processing */ if (*cp == IAC) /* got a telnet command */ telnet_state = TNS_IAC; else *ibptr++ = *cp; break; case TNS_IAC: /* process a telnet command */ switch (*cp) { case IAC: /* escaped IAC, insert it */ *ibptr++ = *cp; telnet_state = TNS_DATA; break; case EOR: /* eor, process accumulated input */ net_process (ibuf, ibptr - ibuf); if (!session_active) return; ibptr = ibuf; telnet_state = TNS_DATA; break; case WILL: telnet_state = TNS_WILL; break; case WONT: telnet_state = TNS_WONT; break; case DO: telnet_state = TNS_DO; break; case DONT: telnet_state = TNS_DONT; break; case SB: telnet_state = TNS_SB; sbptr = sbbuf; break; } break; case TNS_WILL: /* telnet WILL DO OPTION command */ switch (*cp) { case TELOPT_BINARY: case TELOPT_EOR: case TELOPT_TTYPE: if (!hisopts[*cp]) { hisopts[*cp] = 1; do_opt[2] = *cp; (void) write (fd, (char *) do_opt, sizeof (do_opt)); } break; default: dont_opt[2] = *cp; (void) write (fd, (char *) dont_opt, sizeof (dont_opt)); break; } telnet_state = TNS_DATA; break; case TNS_WONT: /* telnet WONT DO OPTION command */ switch (*cp) { case TELOPT_BINARY: case TELOPT_EOR: case TELOPT_TTYPE: (void) fprintf (stderr, "x3270: Remote host won't do option 0%03o.\n", *cp); (void) fprintf (stderr, "x3270: Are you sure it's an IBM?\n"); session_active = FALSE; return; break; default: hisopts[*cp] = 0; break; } telnet_state = TNS_DATA; break; case TNS_DO: /* telnet PLEASE DO OPTION command */ switch (*cp) { case TELOPT_BINARY: case TELOPT_EOR: case TELOPT_TTYPE: if (!myopts[*cp]) { myopts[*cp] = 1; will_opt[2] = *cp; (void) write (fd, (char *) will_opt, sizeof (will_opt)); } break; default: wont_opt[2] = *cp; (void) write (fd, (char *) wont_opt, sizeof (wont_opt)); break; } telnet_state = TNS_DATA; break; case TNS_DONT: /* telnet PLEASE DON'T DO OPTION command */ switch (*cp) { case TELOPT_BINARY: case TELOPT_EOR: case TELOPT_TTYPE: (void) fprintf (stderr, "x3270: Remote host says don't do option 0%03o.\n", *cp); (void) fprintf (stderr, "x3270: Are you sure it's an IBM?\n"); session_active = FALSE; return; break; default: myopts[*cp] = 0; break; } telnet_state = TNS_DATA; break; case TNS_SB: /* telnet sub-option string command */ if (*cp == IAC) telnet_state = TNS_SB_IAC; else *sbptr++ = *cp; break; case TNS_SB_IAC: /* telnet sub-option string command */ if (*cp == SE) { telnet_state = TNS_DATA; if (sbbuf[0] == TELOPT_TTYPE && sbbuf[1] == TELQUAL_SEND) { ttype_opt[13] = model_num + '0'; (void) write (fd, (char *) ttype_opt, sizeof (ttype_opt)); } } else { *sbptr = *cp; /* just stuff it */ telnet_state = TNS_SB; } break; } } } else if (nr == 0) { printf("Connection closed.\n"); session_active = FALSE; retcode = 0; return; } else if (nr < 0 && errno != EWOULDBLOCK) { /* got an error */ perror ("x3270: read(net)"); session_active = FALSE; return; } return; } /* * net_output * Called to send output over the network. Tacks on the necessary * telnet end-of-record command before doing a standard write. */ net_output (buf, buflen) u_char buf[]; int buflen; { extern int net_sock; buf[buflen++] = IAC; buf[buflen++] = EOR; if (write (net_sock, (char *) buf, buflen) != buflen) { perror ("x3270: write(net)"); session_active = FALSE; return; } }