rmpproto.c

早期freebsd实现

/*
 * Copyright (c) 1988, 1992 The University of Utah and the Center
 *	for Software Science (CSS).
 * Copyright (c) 1992, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * the Center for Software Science of the University of Utah Computer
 * Science Department.  CSS requests users of this software to return
 * to [e-mail] any improvements that they make and grant
 * CSS redistribution rights.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)rmpproto.c	8.1 (Berkeley) 6/4/93
 *
 * Utah $Hdr: rmpproto.c 3.1 92/07/06$
 * Author: Jeff Forys, University of Utah CSS
 */

#ifndef lint
static char sccsid[] = "@(#)rmpproto.c	8.1 (Berkeley) 6/4/93";
#endif /* not lint */

#include <sys/param.h>
#include <sys/time.h>

#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include "defs.h"

/*
**  ProcessPacket -- determine packet type and do what's required.
**
**	An RMP BOOT packet has been received.  Look at the type field
**	and process Boot Requests, Read Requests, and Boot Complete
**	packets.  Any other type will be dropped with a warning msg.
**
**	Parameters:
**		rconn - the new connection
**		client - list of files available to this host
**
**	Returns:
**		Nothing.
**
**	Side Effects:
**		- If this is a valid boot request, it will be added to
**		  the linked list of outstanding requests (RmpConns).
**		- If this is a valid boot complete, its associated
**		  entry in RmpConns will be deleted.
**		- Also, unless we run out of memory, a reply will be
**		  sent to the host that sent the packet.
*/
void
ProcessPacket(rconn, client)
	RMPCONN *rconn;
	CLIENT *client;
{
	struct rmp_packet *rmp;
	RMPCONN *rconnout;

	rmp = &rconn->rmp;		/* cache pointer to RMP packet */

	switch(rmp->r_type) {		/* do what we came here to do */
		case RMP_BOOT_REQ:		/* boot request */
			if ((rconnout = NewConn(rconn)) == NULL)
				return;

			/*
			 *  If the Session ID is 0xffff, this is a "probe"
			 *  packet and we do not want to add the connection
			 *  to the linked list of active connections.  There
			 *  are two types of probe packets, if the Sequence
			 *  Number is 0 they want to know our host name, o/w
			 *  they want the name of the file associated with
			 *  the number spec'd by the Sequence Number.
			 *
			 *  If this is an actual boot request, open the file
			 *  and send a reply.  If SendBootRepl() does not
			 *  return 0, add the connection to the linked list
			 *  of active connections, otherwise delete it since
			 *  an error was encountered.
			 */
			if (rmp->r_brq.rmp_session == RMP_PROBESID) {
				if (WORDZE(rmp->r_brq.rmp_seqno))
					(void) SendServerID(rconnout);
				else
					(void) SendFileNo(rmp, rconnout,
					                  client? client->files:
					                          BootFiles);
				FreeConn(rconnout);
			} else {
				if (SendBootRepl(rmp, rconnout,
				    client? client->files: BootFiles))
					AddConn(rconnout);
				else
					FreeConn(rconnout);
			}
			break;

		case RMP_BOOT_REPL:		/* boot reply (not valid) */
			syslog(LOG_WARNING, "%s: sent a boot reply",
			       EnetStr(rconn));
			break;

		case RMP_READ_REQ:		/* read request */
			/*
			 *  Send a portion of the boot file.
			 */
			(void) SendReadRepl(rconn);
			break;

		case RMP_READ_REPL:		/* read reply (not valid) */
			syslog(LOG_WARNING, "%s: sent a read reply",
			       EnetStr(rconn));
			break;

		case RMP_BOOT_DONE:		/* boot complete */
			/*
			 *  Remove the entry from the linked list of active
			 *  connections.
			 */
			(void) BootDone(rconn);
			break;

		default:			/* unknown RMP packet type */
			syslog(LOG_WARNING, "%s: unknown packet type (%u)",
			       EnetStr(rconn), rmp->r_type);
	}
}

/*
**  SendServerID -- send our host name to who ever requested it.
**
**	Parameters:
**		rconn - the reply packet to be formatted.
**
**	Returns:
**		1 on success, 0 on failure.
**
**	Side Effects:
**		none.
*/
int
SendServerID(rconn)
	RMPCONN *rconn;
{
	register struct rmp_packet *rpl;
	register char *src, *dst;
	register u_char *size;

	rpl = &rconn->rmp;			/* cache ptr to RMP packet */

	/*
	 *  Set up assorted fields in reply packet.
	 */
	rpl->r_brpl.rmp_type = RMP_BOOT_REPL;
	rpl->r_brpl.rmp_retcode = RMP_E_OKAY;
	ZEROWORD(rpl->r_brpl.rmp_seqno);
	rpl->r_brpl.rmp_session = 0;
	rpl->r_brpl.rmp_version = RMP_VERSION;

	size = &rpl->r_brpl.rmp_flnmsize;	/* ptr to length of host name */

	/*
	 *  Copy our host name into the reply packet incrementing the
	 *  length as we go.  Stop at RMP_HOSTLEN or the first dot.
	 */
	src = MyHost;
	dst = (char *) &rpl->r_brpl.rmp_flnm;
	for (*size = 0; *size < RMP_HOSTLEN; (*size)++) {
		if (*src == '.' || *src == '\0')
			break;
		*dst++ = *src++;
	}

	rconn->rmplen = RMPBOOTSIZE(*size);	/* set packet length */

	return(SendPacket(rconn));		/* send packet */
}

/*
**  SendFileNo -- send the name of a bootable file to the requester.
**
**	Parameters:
**		req - RMP BOOT packet containing the request.
**		rconn - the reply packet to be formatted.
**		filelist - list of files available to the requester.
**
**	Returns:
**		1 on success, 0 on failure.
**
**	Side Effects:
**		none.
*/
int
SendFileNo(req, rconn, filelist)
	struct rmp_packet *req;
	RMPCONN *rconn;
	char *filelist[];
{
	register struct rmp_packet *rpl;
	register char *src, *dst;
	register u_char *size, i;

	GETWORD(req->r_brpl.rmp_seqno, i);	/* SeqNo is really FileNo */
	rpl = &rconn->rmp;			/* cache ptr to RMP packet */

	/*
	 *  Set up assorted fields in reply packet.
	 */
	rpl->r_brpl.rmp_type = RMP_BOOT_REPL;
	PUTWORD(i, rpl->r_brpl.rmp_seqno);
	i--;
	rpl->r_brpl.rmp_session = 0;
	rpl->r_brpl.rmp_version = RMP_VERSION;

	size = &rpl->r_brpl.rmp_flnmsize;	/* ptr to length of filename */
	*size = 0;				/* init length to zero */

	/*
	 *  Copy the file name into the reply packet incrementing the
	 *  length as we go.  Stop at end of string or when RMPBOOTDATA
	 *  characters have been copied.  Also, set return code to
	 *  indicate success or "no more files".
	 */
	if (i < C_MAXFILE && filelist[i] != NULL) {
		src = filelist[i];
		dst = (char *)&rpl->r_brpl.rmp_flnm;
		for (; *src && *size < RMPBOOTDATA; (*size)++) {
			if (*src == '\0')
				break;
			*dst++ = *src++;
		}
		rpl->r_brpl.rmp_retcode = RMP_E_OKAY;
	} else
		rpl->r_brpl.rmp_retcode = RMP_E_NODFLT;

	rconn->rmplen = RMPBOOTSIZE(*size);	/* set packet length */

	return(SendPacket(rconn));		/* send packet */
}

/*
**  SendBootRepl -- open boot file and respond to boot request.
**
**	Parameters:
**		req - RMP BOOT packet containing the request.
**		rconn - the reply packet to be formatted.
**		filelist - list of files available to the requester.
**
**	Returns:
**		1 on success, 0 on failure.
**
**	Side Effects:
**		none.
*/
int
SendBootRepl(req, rconn, filelist)
	struct rmp_packet *req;
	RMPCONN *rconn;
	char *filelist[];
{
	int retval;
	char *filename, filepath[RMPBOOTDATA+1];
	RMPCONN *oldconn;
	register struct rmp_packet *rpl;