cmd/bnu/pk1.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*  Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/*    All Rights Reserved   */


#pragma ident   "%Z%%M% %I% %E% SMI"

#include "uucp.h"

#include "pk.h"
#include <sys/buf.h>

extern void pkfail(), pkzero(), pkoutput(), pkreset(), pkcntl(), pkgetpack();
extern int pksack();
static void pkdata();
static int pkcget();
static void xlatestate(struct pack *, int);
void xlatecntl(int, int);

/*
 * Code added to allow translation of states from numbers to
 * letters, to be done in such a way as to be meaningful to
 * John Q. Public
 */
struct {
    int state;
    char *msg;
} st_trans[] = {
    DEAD,   "Dead!",
    INITa,  "INIT code a",
    INITb,  "INIT code b",
    LIVE,   "O.K.",
    RXMIT,  "Rcv/Xmit",
    RREJ,   "RREJ?",
    PDEBUG, "PDEBUG?",
    DRAINO, "Draino...",
    WAITO,  "Waiting",
    DOWN,   "Link down",
    RCLOSE, "RCLOSE?",
    BADFRAME,   "Bad frame",
    -1, "End of the line",
};

extern char _Protocol[];    /* Protocol string with (options) */

#define PKMAXSTMSG 40
int Connodata = 0;      /* Continuous Non Valid Data Count */
int Ntimeout = 0;
#define CONNODATA   20  /* Max Continuous Non Valid Data Count */
#define NTIMEOUT    50  /* This is not currently used, but maybe future */

extern jmp_buf Getjbuf;

/*
 * start initial synchronization.
 */
struct pack *
pkopen(ifn, ofn)
int ifn, ofn;
{
    struct pack *pk;
    char **bp;
    int i;
    int windows = WINDOWS;
    extern int xpacksize, packsize;

    if ((pk = (struct pack *) calloc(1, sizeof (struct pack))) == NULL)
        return(NULL);
    pk->p_ifn = ifn;
    pk->p_ofn = ofn;
    DEBUG(7, "Setting up protocol parameters '%s'\n", _Protocol);
    if ( _Protocol[1] == '(' ) {
        if (sscanf(_Protocol, "%*c(%d,%d)", &windows, &packsize) == 0)
        sscanf(_Protocol, "%*c(,%d)", &packsize);
        windows = ( windows < MINWINDOWS ? WINDOWS :
            ( windows > MAXWINDOWS ? WINDOWS : windows ) );
        packsize = ( packsize < MINPACKSIZE ? PACKSIZE :
            ( packsize > MAXPACKSIZE ? PACKSIZE : packsize ) );
    }
    if ( (_Protocol[0] == 'g') && (packsize > OLDPACKSIZE) ) {
        /*
         * We reset to OLDPACKSIZE to maintain compatibility
         * with old limited implementations. Maybe we should
         * just warn the administrator and continue?
         */
        packsize = OLDPACKSIZE;
    }
    pk->p_xsize = pk->p_rsize = xpacksize = packsize;
    pk->p_rwindow = pk->p_swindow = windows;

    /*
     * allocate input window
     */
    for (i = 0; i < pk->p_rwindow; i++) {
        if ((bp = (char **) malloc((unsigned) pk->p_xsize)) == NULL)
            break;
        *bp = (char *) pk->p_ipool;
        pk->p_ipool = bp;
    }
    if (i == 0)
        return(NULL);
    pk->p_rwindow = i;

    /*
     * start synchronization
     */
    pk->p_msg = pk->p_rmsg = M_INITA;
    pkoutput(pk);

    for (i = 0; i < PKMAXSTMSG; i++) {
        pkgetpack(pk);
        if ((pk->p_state & LIVE) != 0)
            break;
    }
    if (i >= PKMAXSTMSG)
        return(NULL);

    pkreset(pk);
    return(pk);
}

/*
 * input framing and block checking.
 * frame layout for most devices is:
 *
 *  S|K|X|Y|C|Z|  ... data ... |
 *
 *  where   S   == initial synch byte
 *      K   == encoded frame size (indexes pksizes[])
 *      X, Y    == block check bytes
 *      C   == control byte
 *      Z   == XOR of header (K^X^Y^C)
 *      data    == 0 or more data bytes
 *
 */
#define GETRIES 10

/*
 * Byte collection.
 */
void
pkgetpack(ipk)
struct pack *ipk;
{
    char *p;
    struct pack *pk;
    struct header *h;
    unsigned short sum;
    int k, tries, ifn, noise;
    char **bp, hdchk;

    pk = ipk;
    /*
     * If we are known to be DOWN, or if we've received too many garbage
     * packets or timeouts, give up without a fight.
     */
    if ((pk->p_state & DOWN) || Connodata > CONNODATA  || Ntimeout > NTIMEOUT)
        pkfail();
    ifn = pk->p_ifn;
    h = &pk->p_ihbuf;

    /*
     * Attempt no more than GETRIES times to read a packet.  The only valid
     * exit from this loop is a return.  Break forces a failure.
     */
    for (tries = 0; tries < GETRIES; tries++) {
        /*
         * Read header.
         * First look for SYN.  If more than 3 * packetsize characters
         * go by w/o a SYN, request a retransmit.
         */
        p = (caddr_t) h;
        noise = 0;
        for ( ; ; ) {
            if (pkcget(ifn, p, HDRSIZ) != SUCCESS) {
                DEBUG(7,
        "Alarm while looking for SYN -- request RXMIT\n%s", "");
                goto retransmit;
            }
            if (*p == SYN)
                break;      /* got it */
            else {
                char *pp, *pend;

                DEBUG(7, "first char not SYN (%x)\n", *p&0xff);
                if ((pp = memchr(p, SYN, HDRSIZ)) != NULL) {
                    pend = p + HDRSIZ;
                    while (pp < pend)
                        *p++ = *pp++;
                    /* Now look for remainder of header */
                    if (pkcget(ifn, p, pend - p) !=
                        SUCCESS) {
                        DEBUG(7,
        "Alarm while looking for header -- request RXMIT\n%s", "");
                        goto retransmit;
                    }
                    p = (caddr_t) h;
                    break;  /* got entire header */
                }
            }
            if ((noise += HDRSIZ) > 3 * pk->p_rsize) {
                DEBUG(7,
            "No SYN in %d characters -- request RXMIT\n", noise);
                goto retransmit;
            }
        }
        /* Validate the header */
        Connodata++;
        hdchk = p[1] ^ p[2] ^ p[3] ^ p[4];
        sum = ((unsigned) p[2] & 0377) | ((unsigned) p[3] << 8);
        h->sum = sum;
        k = h->ksize;
        if (hdchk != h->ccntl) {
            /* bad header */
            DEBUG(7, "bad header checksum\n%s", "");
            return;
        }

        if (k == 9) {   /* control packet */
            if (((h->sum + h->cntl) & 0xffff) == CHECK) {
                pkcntl(h->cntl, pk);
                xlatestate(pk, 7);
            } else {
                /* bad header */
                DEBUG(7, "bad header (k == 9) 0%o\n", h->cntl&0xff);
                pk->p_state |= BADFRAME;
            }
            return;
        }
        /* data packet */
        if (k && pksizes[k] != pk->p_rsize)
            return;
        pk->p_rpr = h->cntl & MOD8;
        pksack(pk);
        if ((bp = pk->p_ipool) == NULL) {
            DEBUG(7, "bp NULL\n%s", "");
            return;
        }
        pk->p_ipool = (char **) *bp;
        /* Header checks out, go for data */
        if (pkcget(pk->p_ifn, (char *) bp, pk->p_rsize) == SUCCESS) {
            pkdata(h->cntl, h->sum, pk, bp);
            Ntimeout = 0;
            return;
        }
        DEBUG(7, "Alarm while reading data -- request RXMIT\n%s", "");
retransmit:
        /*
         * Transmission error or excessive noise.  Send a RXMIT
         * and try again.
         */
/*
        Retries++;
*/
        pk->p_msg |= pk->p_rmsg;
        if (pk->p_msg == 0)
            pk->p_msg |= M_RR;
        if ((pk->p_state & LIVE) == LIVE)
            pk->p_state |= RXMIT;
        pkoutput(pk);
    }
    DEBUG(7, "pkgetpack failed after %d tries\n", tries);
    pkfail();
}

/*
 * Translate pk->p_state into something printable.
 */
static void
xlatestate(pk, dbglvl)
struct pack *pk;
int dbglvl;
{
    int i;
    char delimc = ' ', msgline[80], *buf = msgline;

    if (Debug < dbglvl)
        return;
    sprintf(buf, "state -");
    buf += strlen(buf);
    for(i = 0; st_trans[i].state != -1; i++) {
        if (pk->p_state&st_trans[i].state){
            sprintf(buf, "%c[%s]", delimc, st_trans[i].msg);
            buf += strlen(buf);
            delimc = '&';
        }
    }
    sprintf(buf, " (0%o)\n", pk->p_state);
    DEBUG(dbglvl, "%s", msgline);
    return;
}

static void
pkdata(c, sum, pk, bp)
struct pack *pk;
unsigned short sum;
char c;
char **bp;
{
    int x;
    int t;
    char m;

    if (pk->p_state & DRAINO || !(pk->p_state & LIVE)) {
        pk->p_msg |= pk->p_rmsg;
        pkoutput(pk);
        goto drop;
    }
    t = next[pk->p_pr];
    for(x=pk->p_pr; x!=t; x = (x-1)&7) {
        if (pk->p_is[x] == 0)
            goto slot;
    }
drop:
    *bp = (char *)pk->p_ipool;
    pk->p_ipool = bp;
    return;

slot:
    m = mask[x];
    pk->p_imap |= m;
    pk->p_is[x] = c;
    pk->p_isum[x] = sum;
    pk->p_ib[x] = (char *)bp;
}

/*
 * Start transmission on output device associated with pk.
 * For asynch devices (t_line==1) framing is
 * imposed.  For devices with framing and crc
 * in the driver (t_line==2) the transfer is
 * passed on to the driver.
 */
void
pkxstart(pk, cntl, x)
struct pack *pk;
int x;
char cntl;
{
    char *p;
    short checkword;
    char hdchk;

    p = (caddr_t) &pk->p_ohbuf;
    *p++ = SYN;
    if (x < 0) {
        *p++ = hdchk = 9;
        checkword = cntl;
    } else {
        *p++ = hdchk = pk->p_lpsize;
        checkword = pk->p_osum[x] ^ (unsigned)(cntl & 0377);
    }
    checkword = CHECK - checkword;
    *p = checkword;
    hdchk ^= *p++;
    *p = checkword>>8;
    hdchk ^= *p++;
    *p = cntl;
    hdchk ^= *p++;
    *p = hdchk;

 /*
  * writes
  */
    if (Debug >= 9)
        xlatecntl(1, cntl);

    p = (caddr_t) & pk->p_ohbuf;
    if (x < 0) {
        if ((*Write)(pk->p_ofn, p, HDRSIZ) != HDRSIZ) {
            DEBUG(4, "pkxstart, write failed, %s\n",
                strerror(errno));
            logent(strerror(errno), "PKXSTART WRITE");
            pkfail();
            /* NOT REACHED */
        }
    } else {
        char buf[MAXPACKSIZE + HDRSIZ];

        memcpy(buf, p, HDRSIZ);
        memcpy(buf+HDRSIZ, pk->p_ob[x], pk->p_xsize);
        if ((*Write)(pk->p_ofn, buf, pk->p_xsize + HDRSIZ) !=
            pk->p_xsize + HDRSIZ) {
            DEBUG(4, "pkxstart, write failed, %s\n",
                strerror(errno));
            logent(strerror(errno), "PKXSTART WRITE");
            pkfail();
            /* NOT REACHED */
        }
        Connodata = 0;
    }
    if (pk->p_msg)
        pkoutput(pk);
}

/*
 * get n characters from input
 *  b   -> buffer for characters
 *  fn  -> file descriptor
 *  n   -> requested number of characters
 * return:
 *  SUCCESS -> n chars successfully read
 *  FAIL    -> o.w.
 */

static int
pkcget(fn, b, n)
int n;
char *b;
int fn;
{
    int ret;
#ifdef PKSPEEDUP
    extern int linebaudrate;
    int donap = (linebaudrate > 0 && linebaudrate < 4800);
#endif /*  PKSPEEDUP  */

    if (n == 0)
        return(SUCCESS);
    if (setjmp(Getjbuf)) {
        Ntimeout++;
        DEBUG(4, "pkcget: alarm %d\n", Ntimeout);
        return(FAIL);
    }

    (void) alarm( (unsigned) ( 10 + (n >> 7)) );

    for (;;) {
        ret = (*Read)(fn, b, n);
        (void) alarm(0);
        if (ret == 0) {
            DEBUG(4, "pkcget, read failed, EOF\n", 0);
            /*
             * Device has decided that the connection has no
             * more data to send.  Any further tries are futile...
             * (The only other way to get a zero return value
             * is to read a zero length message from a STREAM.
             * However, uucp *never* sends zero length messages
             * over any sort of channel...)
             */
            pkfail();
            /* NOT REACHED */
        }
        if (ret < 0) {
            DEBUG(4, "pkcget, read failed, %s\n",
                strerror(errno));
            logent(strerror(errno), "PKCGET READ");
            pkfail();
            /* NOT REACHED */
        }
        if ((n -= ret) <= 0)
            break;
#ifdef PKSPEEDUP
        if (donap) {
#if defined(BSD4_2) || defined(ATTSVR4)
            /* wait for more chars to come in */
            nap((n * HZ * 10) / linebaudrate); /* n char times */
#else
            sleep(1);
#endif
        }
#endif /*  PKSPEEDUP  */
        b += ret;
        (void) alarm( (unsigned) ( 10 + (n >> 7)) );
    }
    (void) alarm(0);
    return(SUCCESS);
}

/*
 * role == 0: receive
 * role == 1: send
 */
void
xlatecntl(role, cntl)
int role;
int cntl;
{
    static char *cntltype[4] = {"CNTL, ", "ALT, ", "DATA, ", "SHORT, "};
    static char *cntlxxx[8] = {"ZERO, ", "CLOSE, ", "RJ, ", "SRJ, ",
                   "RR, ", "INITC, ", "INITB, ", "INITA, "};
    char dbgbuf[128];
    char *ptr;

    ptr = dbgbuf;
    strcpy(ptr, role ? "send " : "recv ");
    ptr += strlen(ptr);

    strcpy(ptr, cntltype[(cntl&0300)>>6]);
    ptr += strlen(ptr);

    if (cntl&0300) {
        /* data packet */
        if (role)
            sprintf(ptr, "loc %o, rem %o\n", (cntl & 070) >> 3, cntl & 7);
        else
            sprintf(ptr, "loc %o, rem %o\n", cntl & 7, (cntl & 070) >> 3);
    } else {
        /* control packet */
        strcpy(ptr, cntlxxx[(cntl&070)>>3]);
        ptr += strlen(ptr);
        sprintf(ptr, "val %o\n", cntl & 7);
    }

    DEBUG(1, dbgbuf, 0);
}