freebsd-dev/libexec/rbootd/rmpproto.c
2012-01-07 16:09:54 +00:00

588 lines
16 KiB
C

/*
* 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 css-dist@cs.utah.edu 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.
*
* from: @(#)rmpproto.c 8.1 (Berkeley) 6/4/93
*
* From: Utah Hdr: rmpproto.c 3.1 92/07/06
* Author: Jeff Forys, University of Utah CSS
*/
#ifndef lint
#if 0
static const char sccsid[] = "@(#)rmpproto.c 8.1 (Berkeley) 6/4/93";
#endif
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include <sys/param.h>
#include <sys/time.h>
#include <netinet/in.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(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 (ntohs(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(RMPCONN *rconn)
{
struct rmp_packet *rpl;
char *src, *dst;
u_int8_t *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 = htons(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(struct rmp_packet *req, RMPCONN *rconn, char *filelist[])
{
struct rmp_packet *rpl;
char *src, *dst;
u_int8_t *size;
int 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 = htons(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(struct rmp_packet *req, RMPCONN *rconn, char *filelist[])
{
int retval;
char *filename, filepath[RMPBOOTDATA+1];
RMPCONN *oldconn;
struct rmp_packet *rpl;
char *src, *dst1, *dst2;
u_int8_t i;
/*
* If another connection already exists, delete it since we
* are obviously starting again.
*/
if ((oldconn = FindConn(rconn)) != NULL) {
syslog(LOG_WARNING, "%s: dropping existing connection",
EnetStr(oldconn));
RemoveConn(oldconn);
}
rpl = &rconn->rmp; /* cache ptr to RMP packet */
/*
* Set up assorted fields in reply packet.
*/
rpl->r_brpl.rmp_type = RMP_BOOT_REPL;
COPYWORD(req->r_brq.rmp_seqno, rpl->r_brpl.rmp_seqno);
rpl->r_brpl.rmp_session = htons(GenSessID());
rpl->r_brpl.rmp_version = htons(RMP_VERSION);
rpl->r_brpl.rmp_flnmsize = req->r_brq.rmp_flnmsize;
/*
* Copy file name to `filepath' string, and into reply packet.
*/
src = &req->r_brq.rmp_flnm;
dst1 = filepath;
dst2 = &rpl->r_brpl.rmp_flnm;
for (i = 0; i < req->r_brq.rmp_flnmsize; i++)
*dst1++ = *dst2++ = *src++;
*dst1 = '\0';
/*
* If we are booting HP-UX machines, their secondary loader will
* ask for files like "/hp-ux". As a security measure, we do not
* allow boot files to lay outside the boot directory (unless they
* are purposely link'd out. So, make `filename' become the path-
* stripped file name and spoof the client into thinking that it
* really got what it wanted.
*/
filename = (filename = strrchr(filepath,'/'))? ++filename: filepath;
/*
* Check that this is a valid boot file name.
*/
for (i = 0; i < C_MAXFILE && filelist[i] != NULL; i++)
if (STREQN(filename, filelist[i]))
goto match;
/*
* Invalid boot file name, set error and send reply packet.
*/
rpl->r_brpl.rmp_retcode = RMP_E_NOFILE;
retval = 0;
goto sendpkt;
match:
/*
* This is a valid boot file. Open the file and save the file
* descriptor associated with this connection and set success
* indication. If the file couldnt be opened, set error:
* "no such file or dir" - RMP_E_NOFILE
* "file table overflow" - RMP_E_BUSY
* "too many open files" - RMP_E_BUSY
* anything else - RMP_E_OPENFILE
*/
if ((rconn->bootfd = open(filename, O_RDONLY, 0600)) < 0) {
rpl->r_brpl.rmp_retcode = (errno == ENOENT)? RMP_E_NOFILE:
(errno == EMFILE || errno == ENFILE)? RMP_E_BUSY:
RMP_E_OPENFILE;
retval = 0;
} else {
rpl->r_brpl.rmp_retcode = RMP_E_OKAY;
retval = 1;
}
sendpkt:
syslog(LOG_INFO, "%s: request to boot %s (%s)",
EnetStr(rconn), filename, retval? "granted": "denied");
rconn->rmplen = RMPBOOTSIZE(rpl->r_brpl.rmp_flnmsize);
return (retval & SendPacket(rconn));
}
/*
** SendReadRepl -- send a portion of the boot file to the requester.
**
** Parameters:
** rconn - the reply packet to be formatted.
**
** Returns:
** 1 on success, 0 on failure.
**
** Side Effects:
** none.
*/
int
SendReadRepl(RMPCONN *rconn)
{
int retval = 0;
RMPCONN *oldconn;
struct rmp_packet *rpl, *req;
int size = 0;
int madeconn = 0;
/*
* Find the old connection. If one doesn't exist, create one only
* to return the error code.
*/
if ((oldconn = FindConn(rconn)) == NULL) {
if ((oldconn = NewConn(rconn)) == NULL)
return(0);
syslog(LOG_ERR, "SendReadRepl: no active connection (%s)",
EnetStr(rconn));
madeconn++;
}
req = &rconn->rmp; /* cache ptr to request packet */
rpl = &oldconn->rmp; /* cache ptr to reply packet */
if (madeconn) { /* no active connection above; abort */
rpl->r_rrpl.rmp_retcode = RMP_E_ABORT;
retval = 1;
goto sendpkt;
}
/*
* Make sure Session ID's match.
*/
if (ntohs(req->r_rrq.rmp_session) !=
((rpl->r_type == RMP_BOOT_REPL)? ntohs(rpl->r_brpl.rmp_session):
ntohs(rpl->r_rrpl.rmp_session))) {
syslog(LOG_ERR, "SendReadRepl: bad session id (%s)",
EnetStr(rconn));
rpl->r_rrpl.rmp_retcode = RMP_E_BADSID;
retval = 1;
goto sendpkt;
}
/*
* If the requester asks for more data than we can fit,
* silently clamp the request size down to RMPREADDATA.
*
* N.B. I do not know if this is "legal", however it seems
* to work. This is necessary for bpfwrite() on machines
* with MCLBYTES less than 1514.
*/
if (ntohs(req->r_rrq.rmp_size) > RMPREADDATA)
req->r_rrq.rmp_size = htons(RMPREADDATA);
/*
* Position read head on file according to info in request packet.
*/
GETWORD(req->r_rrq.rmp_offset, size);
if (lseek(oldconn->bootfd, (off_t)size, SEEK_SET) < 0) {
syslog(LOG_ERR, "SendReadRepl: lseek: %m (%s)",
EnetStr(rconn));
rpl->r_rrpl.rmp_retcode = RMP_E_ABORT;
retval = 1;
goto sendpkt;
}
/*
* Read data directly into reply packet.
*/
if ((size = read(oldconn->bootfd, &rpl->r_rrpl.rmp_data,
(int) ntohs(req->r_rrq.rmp_size))) <= 0) {
if (size < 0) {
syslog(LOG_ERR, "SendReadRepl: read: %m (%s)",
EnetStr(rconn));
rpl->r_rrpl.rmp_retcode = RMP_E_ABORT;
} else {
rpl->r_rrpl.rmp_retcode = RMP_E_EOF;
}
retval = 1;
goto sendpkt;
}
/*
* Set success indication.
*/
rpl->r_rrpl.rmp_retcode = RMP_E_OKAY;
sendpkt:
/*
* Set up assorted fields in reply packet.
*/
rpl->r_rrpl.rmp_type = RMP_READ_REPL;
COPYWORD(req->r_rrq.rmp_offset, rpl->r_rrpl.rmp_offset);
rpl->r_rrpl.rmp_session = req->r_rrq.rmp_session;
oldconn->rmplen = RMPREADSIZE(size); /* set size of packet */
retval &= SendPacket(oldconn); /* send packet */
if (madeconn) /* clean up after ourself */
FreeConn(oldconn);
return (retval);
}
/*
** BootDone -- free up memory allocated for a connection.
**
** Parameters:
** rconn - incoming boot complete packet.
**
** Returns:
** 1 on success, 0 on failure.
**
** Side Effects:
** none.
*/
int
BootDone(RMPCONN *rconn)
{
RMPCONN *oldconn;
struct rmp_packet *rpl;
/*
* If we can't find the connection, ignore the request.
*/
if ((oldconn = FindConn(rconn)) == NULL) {
syslog(LOG_ERR, "BootDone: no existing connection (%s)",
EnetStr(rconn));
return(0);
}
rpl = &oldconn->rmp; /* cache ptr to RMP packet */
/*
* Make sure Session ID's match.
*/
if (ntohs(rconn->rmp.r_rrq.rmp_session) !=
((rpl->r_type == RMP_BOOT_REPL)? ntohs(rpl->r_brpl.rmp_session):
ntohs(rpl->r_rrpl.rmp_session))) {
syslog(LOG_ERR, "BootDone: bad session id (%s)",
EnetStr(rconn));
return(0);
}
RemoveConn(oldconn); /* remove connection */
syslog(LOG_INFO, "%s: boot complete", EnetStr(rconn));
return(1);
}
/*
** SendPacket -- send an RMP packet to a remote host.
**
** Parameters:
** rconn - packet to be sent.
**
** Returns:
** 1 on success, 0 on failure.
**
** Side Effects:
** none.
*/
int
SendPacket(RMPCONN *rconn)
{
/*
* Set Ethernet Destination address to Source (BPF and the enet
* driver will take care of getting our source address set).
*/
memmove((char *)&rconn->rmp.hp_hdr.daddr[0],
(char *)&rconn->rmp.hp_hdr.saddr[0], RMP_ADDRLEN);
rconn->rmp.hp_hdr.len = htons(rconn->rmplen - sizeof(struct hp_hdr));
/*
* Reverse 802.2/HP Extended Source & Destination Access Pts.
*/
rconn->rmp.hp_llc.dxsap = htons(HPEXT_SXSAP);
rconn->rmp.hp_llc.sxsap = htons(HPEXT_DXSAP);
/*
* Last time this connection was active.
*/
(void) gettimeofday(&rconn->tstamp, (struct timezone *)0);
if (DbgFp != NULL) /* display packet */
DispPkt(rconn,DIR_SENT);
/*
* Send RMP packet to remote host.
*/
return(BpfWrite(rconn));
}