ckcnet.c

C-Kermit源码。是使用串口/Modem和网络通讯的程序

#ifdef TCPIPLIB

/* For buffered network reads... */
/*
  If the buffering code is written right, it shouldn't matter
  how long this buffer is.
*/
#ifdef OS2
#ifdef NT
#define TTIBUFL 64240                   /* 44 * 1460 (MSS) */
#else
#define TTIBUFL 32120                   /* 22 * 1460 (MSS) */
#endif /* NT */
#else /* OS2 */
#define TTIBUFL 8191                    /* Let's use 8K. */
#endif /* OS2 */

CHAR ttibuf[TTIBUFL+1];

/*
  select() is used in preference to alarm()/signal(), but different systems
  use different forms of select()...
*/
#ifndef NOSELECT         /* Option to override BSDSELECT */
#ifdef BELLV10
/*
  Note: Although BELLV10 does have TCP/IP support, and does use the unique
  form of select() that is evident in this module (and in ckutio.c), it does
  not have a sockets library and so we can't build Kermit TCP/IP support for
  it.  For this, somebody would have to write TCP/IP streams code.
*/
#define BELLSELECT
#ifndef FD_SETSIZE
#define FD_SETSIZE 128
#endif /* FD_SETSIZE */
#else
#ifdef WINTCP                           /* VMS with Wollongong WIN/TCP */
#ifndef OLD_TWG                         /* TWG 3.2 has only select(read) */
#define BSDSELECT
#endif /* OLD_TWG */
#else
#ifdef CMU_TCPIP                        /* LIBCMU can do select */
#define BSDSELECT
#else
#ifdef DEC_TCPIP
#define BSDSELECT
#else
#ifdef OS2                              /* OS/2 with TCP/IP */
#ifdef NT
#define BSDSELECT
#else /* NT */
#define IBMSELECT
#endif /* NT */
#endif /* OS2 */
#endif /* DEC_TCPIP */
#endif /* CMU_TCPIP */
#endif /* WINTCP */
#endif /* BELLV10 */
#endif /* NOSELECT */
/*
  Others (TGV, TCPware, ...) use alarm()/signal().  The BSDSELECT case does not
  compile at all; the IBMSELECT case compiles and links but crashes at runtime.
  NOTE: If any of these can be converted to select(), they should be for two
  reasons: (1) It's a lot faster; (2) certain sockets libraries do not like
  their socket_read() calls to be interrupted; subsequent socket_read()'s tend
  to fail with EBUSY.  This happened in the UCX case before it was converted
  to use select().
*/
#ifndef OS2
#ifndef VMS
static                                  /* These are used in CKVTIO.C */
#endif /* VMS */                        /* And in CKONET.C            */
#endif /* OS2 */
int
  ttibp = 0,
  ttibn = 0;
/*
  Read bytes from network into internal buffer ttibuf[].
  To be called when input buffer is empty, i.e. when ttibn == 0.

  Other network reading routines, like ttinc, ttinl, ttxin, should check the
  internal buffer first, and call this routine for a refill if necessary.

  Returns -1 on error, 0 if nothing happens.  When data is read successfully,
  returns number of bytes read, and sets global ttibn to that number and
  ttibp (the buffer pointer) to zero.
*/
_PROTOTYP( int ttbufr, ( VOID ) );
int
ttbufr() {                              /* TT Buffer Read */
    int count;

    if (ttnet != NET_TCPB)              /* First make sure current net is */
      return(-1);                       /* TCP/IP; if not, do nothing. */

    if (ttibn > 0)                      /* Our internal buffer is not empty, */
      return(ttibn);                    /* so keep using it. */

    ttibp = 0;                          /* Else reset pointer to beginning */

    if (ttyfd == -1)                    /* No connection, error */
        return(-2);

#ifdef WINTCP
    count = 512;                        /* This works for WIN/TCP */
#else
#ifdef DEC_TCPIP
    count = 512;                        /* UCX */
#else
#ifdef OS2
    count = TTIBUFL;
#else                                   /* Multinet, etc. */
    count = ttchk();                    /* Check network input buffer, */
    if (ttibn > 0) {                    /* which can put a char there! */
        debug(F111,"ttbufr","ttchk() returns",count);
        return(ttibn);
    }
    if (count < 0)                      /* Read error - connection closed */
      return(-2);
    else if (count > TTIBUFL)           /* Too many to read */
      count = TTIBUFL;
    else if (count == 0)                /* None, so force blocking read */
      count = 1;
#endif /* OS2 */
#endif /* DEC_TCPIP */
#endif /* WINTCP */
    debug(F101,"ttbufr count 1","",count);

#ifdef CK_SSL
    if (ssl_active_flag || tls_active_flag) {
        int error;
        if (ssl_active_flag)
          count = SSL_read(ssl_con, ttibuf, count);
        else
          count = SSL_read(tls_con, ttibuf, count);
        switch (SSL_get_error(ssl_active_flag?ssl_con:tls_con,count)) {
          case SSL_ERROR_NONE:
            debug(F111,"ttbufr SSL_ERROR_NONE","count",count);
            if (count > 0) {
                ttibp = 0;              /* Reset buffer pointer. */
                ttibn = count;
                return(ttibn);          /* Return buffer count. */
            } else if (count < 0) {
                return(-1);
            } else {
                netclos();
                return(-2);
            }
          case SSL_ERROR_WANT_WRITE:
            debug(F100,"ttbufr SSL_ERROR_WANT_WRITE","",0);
            return(-1);
          case SSL_ERROR_WANT_READ:
            debug(F100,"ttbufr SSL_ERROR_WANT_READ","",0);
            return(-1);
          case SSL_ERROR_SYSCALL:
#ifdef NT
            debug(F111,"ttbufr SSL_ERROR_SYSCALL",
                  "GetLastError()",GetLastError());
#endif /* NT */
            netclos();
            return(-2);
          case SSL_ERROR_WANT_X509_LOOKUP:
            debug(F100,"ttbufr SSL_ERROR_WANT_X509_LOOKUP","",0);
            netclos();
            return(-2);
          case SSL_ERROR_SSL:
            debug(F100,"ttbufr SSL_ERROR_SSL","",0);
            netclos();
            return(-2);
          case SSL_ERROR_ZERO_RETURN:
            debug(F100,"ttbufr SSL_ERROR_ZERO_RETURN","",0);
            netclos();
            return(-2);
          default:
            debug(F100,"ttbufr SSL_ERROR_?????","",0);
            netclos();
            return(-2);
        }
    }
#endif /* CK_SSL */

#ifdef COMMENT
/*
 This is for nonblocking reads, which we don't do any more.  This code didn't
 work anyway, in the sense that a broken connection was never sensed.
*/
    if ((count = socket_read(ttyfd,&ttibuf[ttibp+ttibn],count)) < 1) {
        if (count == -1 && socket_errno == EWOULDBLOCK) {
            debug(F100,"ttbufr finds nothing","",0);
            return(0);
        } else {
            debug(F101,"ttbufr socket_read error","",socket_errno);
            return(-1);
        }

    } else if (count == 0) {
        debug(F100,"ttbufr socket eof","",0);
        return(-1);
    }
#else /* COMMENT */

/* This is for blocking reads */

#ifndef VMS
#ifdef SO_OOBINLINE
    {
        int outofband = 0;
#ifdef BELLSELECT
        if (select(128, NULL, NULL, efds, 0) > 0 && FD_ISSET(ttyfd, efds))
          outofband = 1;
#else
#ifdef BSDSELECT
        fd_set efds;
        struct timeval tv;
        FD_ZERO(&efds);
        FD_SET(ttyfd, &efds);
        tv.tv_sec  = tv.tv_usec = 0L;
        debug(F100,"Out-of-Band BSDSELECT","",0);
#ifdef NT
        WSASafeToCancel = 1;
#endif /* NT */
        if (select(FD_SETSIZE, NULL, NULL, &efds, &tv) > 0 &&
            FD_ISSET(ttyfd, &efds))
          outofband = 1;
#ifdef NT
        WSASafeToCancel = 0;
#endif /* NT */
#else /* !BSDSELECT */
#ifdef IBMSELECT
/* Was used by OS/2, currently not used, but might come in handy some day... */
/* ... and it came in handy!  For our TCP/IP layer, it avoids all the fd_set */
/* and timeval stuff since this is the only place where it is used. */
        int socket = ttyfd;
        debug(F100,"Out-of-Band IBMSELECT","",0);
        if ((select(&socket, 0, 0, 1, 0L) == 1) && (socket == ttyfd))
          outofband = 1;
#else /* !IBMSELECT */
/*
  If we can't use select(), then we use the regular alarm()/signal()
  timeout mechanism.
*/
      debug(F101,"Out-of-Band data not supported","",0);
      outofband = 0;

#endif /* IBMSELECT */
#endif /* BSDSELECT */
#endif /* BELLSELECT */
      if (outofband) {
         /* Get the Urgent Data */
         /* if OOBINLINE is disabled this should be only a single byte      */
         /* MS Winsock has a bug in Windows 95.  Extra bytes are delivered  */
         /* That were never sent.                                           */
#ifdef OS2
          RequestTCPIPMutex(SEM_INDEFINITE_WAIT);
#endif /* OS2 */
          count = socket_recv(ttyfd,&ttibuf[ttibp+ttibn],count,MSG_OOB);
#ifdef OS2
          ReleaseTCPIPMutex();
#endif /* OS2 */
          if (count <= 0) {
              int s_errno = socket_errno;
              debug(F101, "ttbufr socket_recv MSG_OOB","",count);
              debug(F101, "ttbufr socket_errno","",s_errno);
#ifdef OS2ONLY
              if (count < 0 && (s_errno == 0 || s_errno == 23)) {
                  /* These appear in OS/2 - don't know why   */
                  /* ignore it and read as normal data       */
                  /* and break, then we will attempt to read */
                  /* the port using normal read() techniques */
                  debug(F100,"ttbufr handing as in-band data","",0);
                  count = 1;
              } else {
                  netclos();                    /* *** *** */
                  return(-2);
              }
#else /* OS2ONLY */
              netclos();                        /* *** *** */
              return(-2);
#endif /* OS2ONLY */
          } else {                      /* we got out-of-band data */
              hexdump("ttbufr out-of-band chars",&ttibuf[ttibp+ttibn],count);
#ifdef BETATEST
              bleep(BP_NOTE);
#endif /* BETATEST */
#ifdef RLOGCODE                         /* blah */
              if (ttnproto == NP_RLOGIN  ||
                  ttnproto == NP_K4LOGIN || ttnproto == NP_EK4LOGIN ||
                  ttnproto == NP_K5LOGIN || ttnproto == NP_EK5LOGIN
                   ) {
                  /*
                    When urgent data is read with MSG_OOB and not OOBINLINE
                    then urgent data and normal data are not mixed.  So
                    treat the entire buffer as urgent data.
                  */
                  rlog_oob(&ttibuf[ttibp+ttibn], count);
                  return ttbufr();
              } else
#endif /* RLOGCODE */ /* blah */
#ifdef COMMENT
            /*
               I haven't written this yet, nor do I know what it should do
             */
                if (ttnproto == NP_TELNET) {
                    tn_oob();
                    return 0;
                } else
#endif /* COMMENT */
                  {
                   /* For any protocols we don't have a special out-of-band  */
                   /* handler for, just put the bytes in the normal buffer   */
                   /* and return                                             */

#ifdef OS2
                      RequestTCPIPMutex(SEM_INDEFINITE_WAIT);
#endif /* OS2 */
                      ttibp += 0;       /* Reset buffer pointer. */
                      ttibn += count;
#ifdef OS2
                      ReleaseTCPIPMutex();
#endif /* OS2 */
#ifdef DEBUG
                      /* Got some bytes. */
                      debug(F101,"ttbufr count 2","",count);
                      if (count > 0)
                        ttibuf[ttibp+ttibn] = '\0';
                      debug(F111,"ttbufr ttibuf",ttibuf,ttibp);
#endif /* DEBUG */
                      return(ttibn);    /* Return buffer count. */
                  }
          }
      }
    }
#endif /* SO_OOBINLINE */
#endif /* VMS */

#ifdef OS2
    RequestTCPIPMutex(SEM_INDEFINITE_WAIT);
#endif /* OS2 */
    count = socket_read(ttyfd,&ttibuf[ttibp+ttibn],count);
#ifdef OS2
    ReleaseTCPIPMutex();
#endif /* OS2 */
    if (count <= 0) {
        int s_errno = socket_errno;
        debug(F101,"ttbufr socket_read","",count);
        debug(F101,"ttbufr socket_errno","",s_errno);
#ifdef OS2
        if (count == 0 || os2socketerror(s_errno) < 0) {
            netclos();
            return(-2);
        }
        return(-1);
#else /* OS2 */
        netclos();                      /* *** *** */
        return(-2);
#endif /* OS2 */
    }
#endif /* COMMENT */ /* (blocking vs nonblock reads...) */
    else {
#ifdef OS2
    RequestTCPIPMutex(SEM_INDEFINITE_WAIT);
#endif /* OS2 */
        ttibp = 0;                      /* Reset buffer pointer. */
        ttibn += count;
#ifdef OS2
    ReleaseTCPIPMutex();
#endif /* OS2 */
#ifdef DEBUG
        debug(F101,"ttbufr count 2","",count); /* Got some bytes. */
        if (count > 0)
          ttibuf[ttibp+ttibn] = '\0';
        debug(F111,"ttbufr ttibuf",&ttibuf[ttibp],ttibn);
#endif /* DEBUG */
        return(ttibn);                  /* Return buffer count. */
    }
}
#endif /* TCPIPLIB */

#ifndef IBMSELECT
#ifndef BELLSELECT
#ifndef BSDSELECT               /* Non-TCPIPLIB case */
#ifdef SELECT
#define BSDSELECT
#endif /* SELECT */
#endif /* BSDSELECT */
#endif /* BELLSELECT */
#endif /* IBMSELECT */

#define TELNET_PORT 23          /* Should do lookup, but it won't change */
#define RLOGIN_PORT 513
#define KERMIT_PORT 1649
#define KLOGIN_PORT 543
#define EKLOGIN_PORT 2105

/* Type needed as 5th argument (length) to get/setsockopt() */

#ifndef SOCKOPT_T
#define SOCKOPT_T int
#ifdef AIX42
#undef SOCKOPT_T
#define SOCKOPT_T unsigned long
#else
#ifdef PTX
#undef SOCKOPT_T
#define SOCKOPT_T size_t
#else
#ifdef NT
#undef SOCKOPT_T
#define SOCKOPT_T int
#else /* NT */
#ifdef UNIXWARE
#undef SOCKOPT_T
#define SOCKOPT_T size_t
#else /* UNIXWARE */
#ifdef VMS
#ifdef DEC_TCPIP
#ifdef __DECC_VER
#undef SOCKOPT_T
#define SOCKOPT_T size_t
#endif /* __DECC_VER */
#endif /* DEC_TCPIP */
#endif /* VMS */
#endif /* UNIXWARE */