NetBSD/usr.sbin/sup/source/scm.c

614 lines
17 KiB
C

/*
* Copyright (c) 1992 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software_Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
*/
/*
* SUP Communication Module for 4.3 BSD
*
* SUP COMMUNICATION MODULE SPECIFICATIONS:
*
* IN THIS MODULE:
*
* CONNECTION ROUTINES
*
* FOR SERVER
* servicesetup (port) establish TCP port connection
* char *port; name of service
* service () accept TCP port connection
* servicekill () close TCP port in use by another process
* serviceprep () close temp ports used to make connection
* serviceend () close TCP port
*
* FOR CLIENT
* request (port,hostname,retry) establish TCP port connection
* char *port,*hostname; name of service and host
* int retry; true if retries should be used
* requestend () close TCP port
*
* HOST NAME CHECKING
* p = remotehost () remote host name (if known)
* char *p;
* i = samehost () whether remote host is also this host
* int i;
* i = matchhost (name) whether remote host is same as name
* int i;
* char *name;
*
* RETURN CODES
* All procedures return values as indicated above. Other routines
* normally return SCMOK on success, SCMERR on error.
*
* COMMUNICATION PROTOCOL
*
* Described in scmio.c.
*
**********************************************************************
* HISTORY
* 2-Oct-92 Mary Thompson (mrt) at Carnegie-Mellon University
* Added conditional declarations of INADDR_NONE and INADDR_LOOPBACK
* since Tahoe version of <netinet/in.h> does not define them.
*
* $Log: scm.c,v $
* Revision 1.3 1996/09/05 16:50:05 christos
* - for portability make sure that we never use "" as a pathname, always convert
* it to "."
* - include sockio.h if needed to define SIOCGIFCONF (for svr4)
* - use POSIX signals and wait macros
* - add -S silent flag, so that the client does not print messages unless there
* is something wrong
* - use flock or lockf as appropriate
* - use fstatfs or fstatvfs to find out if a filesystem is mounted over nfs,
* don't depend on the major() = 255 hack; it only works on legacy systems.
* - use gzip -cf to make sure that gzip compresses the file even when the file
* would expand.
* - punt on defining vsnprintf if _IOSTRG is not defined; use sprintf...
*
* To compile sup on systems other than NetBSD, you'll need a copy of daemon.c,
* vis.c, vis.h and sys/cdefs.h. Maybe we should keep those in the distribution?
*
* Revision 1.2 1995/06/03 21:21:51 christos
* Changes to write ascii timestamps in the when files.
* Looked into making it 64 bit clean, but it is hopeless.
* Added little program to convert from the old timestamp files
* into the new ones.
*
* Revision 1.1.1.1 1993/05/21 14:52:17 cgd
* initial import of CMU's SUP to NetBSD
*
* Revision 1.13 92/08/11 12:05:35 mrt
* Added changes from stump:
* Allow for multiple interfaces, and for numeric addresses.
* Changed to use builtin port for the "supfiledbg"
* service when getservbyname() cannot find it.
* Added forward static declatations, delinted.
* Updated variable argument usage.
* [92/08/08 mrt]
*
* Revision 1.12 92/02/08 19:01:11 mja
* Add (struct sockaddr *) casts for HC 2.1.
* [92/02/08 18:59:09 mja]
*
* Revision 1.11 89/08/03 19:49:03 mja
* Updated to use v*printf() in place of _doprnt().
* [89/04/19 mja]
*
* 11-Feb-88 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Moved sleep into computeBackoff, renamed to dobackoff.
*
* 10-Feb-88 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Added timeout to backoff.
*
* 27-Dec-87 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Removed nameserver support.
*
* 09-Sep-87 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Fixed to depend less upon having name of remote host.
*
* 25-May-87 Doug Philips (dwp) at Carnegie-Mellon Universtiy
* Extracted backoff/sleeptime computation from "request" and
* created "computeBackoff" so that I could use it in sup.c when
* trying to get to nameservers as a group.
*
* 21-May-87 Chriss Stephens (chriss) at Carnegie Mellon University
* Merged divergent CS and EE versions.
*
* 02-May-87 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Added some bullet-proofing code around hostname calls.
*
* 31-Mar-87 Dan Nydick (dan) at Carnegie-Mellon University
* Fixed for 4.3.
*
* 30-May-86 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Added code to use known values for well-known ports if they are
* not found in the host table.
*
* 19-Feb-86 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Changed setsockopt SO_REUSEADDR to be non-fatal. Added fourth
* parameter as described in 4.3 manual entry.
*
* 15-Feb-86 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Added call of readflush() to requestend() routine.
*
* 29-Dec-85 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Major rewrite for protocol version 4. All read/write and crypt
* routines are now in scmio.c.
*
* 14-Dec-85 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Added setsockopt SO_REUSEADDR call.
*
* 01-Dec-85 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Removed code to "gracefully" handle unexpected messages. This
* seems reasonable since it didn't work anyway, and should be
* handled at a higher level anyway by adhering to protocol version
* number conventions.
*
* 26-Nov-85 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Fixed scm.c to free space for remote host name when connection
* is closed.
*
* 07-Nov-85 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Fixed 4.2 retry code to reload sin values before retry.
*
* 22-Oct-85 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Added code to retry initial connection open request.
*
* 22-Sep-85 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Merged 4.1 and 4.2 versions together.
*
* 21-Sep-85 Glenn Marcy (gm0w) at Carnegie-Mellon University
* Add close() calls after pipe() call.
*
* 12-Jun-85 Steven Shafer (sas) at Carnegie-Mellon University
* Converted for 4.2 sockets; added serviceprep() routine.
*
* 04-Jun-85 Steven Shafer (sas) at Carnegie-Mellon University
* Created for 4.2 BSD.
*
**********************************************************************
*/
#include <libc.h>
#include <errno.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#ifndef SIOCGIFCONF
#include <sys/sockio.h>
#endif
#include <netinet/in.h>
#include <arpa/inet.h>
#include <net/if.h>
#include <netdb.h>
#if __STDC__
#include <stdarg.h>
#else
#include <varargs.h>
#endif
#include "sup.h"
#ifndef INADDR_NONE
#define INADDR_NONE 0xffffffff /* -1 return */
#endif
#ifndef INADDR_LOOPBACK
#define INADDR_LOOPBACK (u_long)0x7f000001 /* 127.0.0.1 */
#endif
extern int errno;
static char *myhost ();
char scmversion[] = "4.3 BSD";
extern int silent;
/*************************
*** M A C R O S ***
*************************/
/* networking parameters */
#define NCONNECTS 5
/*********************************************
*** G L O B A L V A R I A B L E S ***
*********************************************/
extern char program[]; /* name of program we are running */
extern int progpid; /* process id to display */
int netfile = -1; /* network file descriptor */
static int sock = -1; /* socket used to make connection */
static struct in_addr remoteaddr; /* remote host address */
static char *remotename = NULL; /* remote host name */
static int swapmode; /* byte-swapping needed on server? */
#if __STDC__
int scmerr(int,char *,...);
#endif
/***************************************************
*** C O N N E C T I O N R O U T I N E S ***
*** F O R S E R V E R ***
***************************************************/
servicesetup (server) /* listen for clients */
char *server;
{
struct sockaddr_in sin;
struct servent *sp;
short port;
int one = 1;
if (myhost () == NULL)
return (scmerr (-1,"Local hostname not known"));
if ((sp = getservbyname(server,"tcp")) == 0) {
if (strcmp(server, FILEPORT) == 0)
port = htons((u_short)FILEPORTNUM);
else if (strcmp(server, DEBUGFPORT) == 0)
port = htons((u_short)DEBUGFPORTNUM);
else
return (scmerr (-1,"Can't find %s server description",server));
(void) scmerr (-1,"%s/tcp: unknown service: using port %d",
server,port);
} else
port = sp->s_port;
endservent ();
sock = socket (AF_INET,SOCK_STREAM,0);
if (sock < 0)
return (scmerr (errno,"Can't create socket for connections"));
if (setsockopt (sock,SOL_SOCKET,SO_REUSEADDR,(char *)&one,sizeof(int)) < 0)
(void) scmerr (errno,"Can't set SO_REUSEADDR socket option");
(void) bzero ((char *)&sin,sizeof(sin));
sin.sin_family = AF_INET;
sin.sin_port = port;
if (bind (sock,(struct sockaddr *)&sin,sizeof(sin)) < 0)
return (scmerr (errno,"Can't bind socket for connections"));
if (listen (sock,NCONNECTS) < 0)
return (scmerr (errno,"Can't listen on socket"));
return (SCMOK);
}
service ()
{
struct sockaddr_in from;
int x,len;
remotename = NULL;
len = sizeof (from);
do {
netfile = accept (sock,(struct sockaddr *)&from,&len);
} while (netfile < 0 && errno == EINTR);
if (netfile < 0)
return (scmerr (errno,"Can't accept connections"));
remoteaddr = from.sin_addr;
if (read(netfile,(char *)&x,sizeof(int)) != sizeof(int))
return (scmerr (errno,"Can't transmit data on connection"));
if (x == 0x01020304)
swapmode = 0;
else if (x == 0x04030201)
swapmode = 1;
else
return (scmerr (-1,"Unexpected byteswap mode %x",x));
return (SCMOK);
}
serviceprep () /* kill temp socket in daemon */
{
if (sock >= 0) {
(void) close (sock);
sock = -1;
}
return (SCMOK);
}
servicekill () /* kill net file in daemon's parent */
{
if (netfile >= 0) {
(void) close (netfile);
netfile = -1;
}
if (remotename) {
free (remotename);
remotename = NULL;
}
return (SCMOK);
}
serviceend () /* kill net file after use in daemon */
{
if (netfile >= 0) {
(void) close (netfile);
netfile = -1;
}
if (remotename) {
free (remotename);
remotename = NULL;
}
return (SCMOK);
}
/***************************************************
*** C O N N E C T I O N R O U T I N E S ***
*** F O R C L I E N T ***
***************************************************/
dobackoff (t,b)
int *t,*b;
{
struct timeval tt;
unsigned s;
if (*t == 0)
return (0);
s = *b * 30;
if (gettimeofday (&tt,(struct timezone *)NULL) >= 0)
s += (tt.tv_usec >> 8) % s;
if (*b < 32) *b <<= 1;
if (*t != -1) {
if (s > *t)
s = *t;
*t -= s;
}
if (!silent)
(void) scmerr (-1,"Will retry in %d seconds",s);
sleep (s);
return (1);
}
request (server,hostname,retry) /* connect to server */
char *server;
char *hostname;
int *retry;
{
int x, backoff;
struct hostent *h;
struct servent *sp;
struct sockaddr_in sin, tin;
short port;
if ((sp = getservbyname(server,"tcp")) == 0) {
if (strcmp(server, FILEPORT) == 0)
port = htons((u_short)FILEPORTNUM);
else if (strcmp(server, DEBUGFPORT) == 0)
port = htons((u_short)DEBUGFPORTNUM);
else
return (scmerr (-1,"Can't find %s server description",
server));
if (!silent)
(void) scmerr (-1,"%s/tcp: unknown service: using port %d",
server,port);
} else
port = sp->s_port;
(void) bzero ((char *)&sin,sizeof(sin));
sin.sin_family = AF_INET;
sin.sin_addr.s_addr = inet_addr (hostname);
if (sin.sin_addr.s_addr == (u_long) INADDR_NONE) {
if ((h = gethostbyname (hostname)) == NULL)
return (scmerr (-1,"Can't find host entry for %s",
hostname));
hostname = h->h_name;
(void) bcopy (h->h_addr,(char *)&sin.sin_addr,h->h_length);
}
sin.sin_port = port;
backoff = 1;
for (;;) {
netfile = socket (AF_INET,SOCK_STREAM,0);
if (netfile < 0)
return (scmerr (errno,"Can't create socket"));
tin = sin;
if (connect(netfile,(struct sockaddr *)&tin,sizeof(tin)) >= 0)
break;
(void) scmerr (errno,"Can't connect to server for %s",server);
(void) close(netfile);
if (!dobackoff (retry,&backoff))
return (SCMERR);
}
remoteaddr = sin.sin_addr;
remotename = salloc(hostname);
x = 0x01020304;
(void) write (netfile,(char *)&x,sizeof(int));
swapmode = 0; /* swap only on server, not client */
return (SCMOK);
}
requestend () /* end connection to server */
{
(void) readflush ();
if (netfile >= 0) {
(void) close (netfile);
netfile = -1;
}
if (remotename) {
free (remotename);
remotename = NULL;
}
return (SCMOK);
}
/*************************************************
*** H O S T N A M E C H E C K I N G ***
*************************************************/
static
char *myhost () /* find my host name */
{
struct hostent *h;
static char name[MAXHOSTNAMELEN];
if (name[0] == '\0') {
if (gethostname (name,MAXHOSTNAMELEN) < 0)
return (NULL);
if ((h = gethostbyname (name)) == NULL)
return (NULL);
(void) strcpy (name,h->h_name);
}
return (name);
}
char *remotehost () /* remote host name (if known) */
{
register struct hostent *h;
if (remotename == NULL) {
h = gethostbyaddr ((char *)&remoteaddr,sizeof(remoteaddr),
AF_INET);
remotename = salloc (h ? h->h_name : inet_ntoa(remoteaddr));
if (remotename == NULL)
return("UNKNOWN");
}
return (remotename);
}
int thishost (host)
register char *host;
{
register struct hostent *h;
char *name;
if ((name = myhost ()) == NULL)
logquit (1,"Can't find my host entry");
h = gethostbyname (host);
if (h == NULL) return (0);
return (strcasecmp (name,h->h_name) == 0);
}
int samehost () /* is remote host same as local host? */
{
static struct in_addr *intp;
static int nint = 0;
struct in_addr *ifp;
int n;
if (nint <= 0) {
int s;
char buf[BUFSIZ];
struct ifconf ifc;
struct ifreq *ifr;
struct sockaddr_in sin;
if ((s = socket (AF_INET,SOCK_DGRAM,0)) < 0)
logquit (1,"Can't create socket for SIOCGIFCONF");
ifc.ifc_len = sizeof(buf);
ifc.ifc_buf = buf;
if (ioctl (s,SIOCGIFCONF,(char *)&ifc) < 0)
logquit (1,"SIOCGIFCONF failed");
(void) close(s);
if ((nint = ifc.ifc_len/sizeof(struct ifreq)) <= 0)
return (0);
intp = (struct in_addr *)
malloc ((unsigned) nint*sizeof(struct in_addr));
if ((ifp = intp) == 0)
logquit (1,"no space for interfaces");
for (ifr = ifc.ifc_req, n = nint; n > 0; --n, ifr++) {
(void) bcopy ((char *)&ifr->ifr_addr,(char *)&sin,sizeof(sin));
*ifp++ = sin.sin_addr;
}
}
if (remoteaddr.s_addr == htonl(INADDR_LOOPBACK))
return (1);
for (ifp = intp, n = nint; n > 0; --n, ifp++)
if (remoteaddr.s_addr == ifp->s_addr)
return (1);
return (0);
}
int matchhost (name) /* is this name of remote host? */
char *name;
{
struct hostent *h;
struct in_addr addr;
char **ap;
if ((addr.s_addr = inet_addr(name)) != (u_long) INADDR_NONE)
return (addr.s_addr == remoteaddr.s_addr);
if ((h = gethostbyname (name)) == 0)
return (0);
if (h->h_addrtype != AF_INET || h->h_length != sizeof(struct in_addr))
return (0);
for (ap = h->h_addr_list; *ap; ap++)
if (bcmp ((char *)&remoteaddr,*ap,h->h_length) == 0)
return (1);
return (0);
}
#if __STDC__
int scmerr (int errno,char *fmt,...)
#else
/*VARARGS*//*ARGSUSED*/
int scmerr (va_alist)
va_dcl
#endif
{
#if !__STDC__
int errno;
char *fmt;
#endif
va_list ap;
(void) fflush (stdout);
if (progpid > 0)
fprintf (stderr,"%s %d: ",program,progpid);
else
fprintf (stderr,"%s: ",program);
#if __STDC__
va_start(ap,fmt);
#else
va_start(ap);
errno = va_arg(ap,int);
fmt = va_arg(ap,char *);
#endif
vfprintf(stderr, fmt, ap);
va_end(ap);
if (errno >= 0)
fprintf (stderr,": %s\n",errmsg(errno));
else
fprintf (stderr,"\n");
(void) fflush (stderr);
return (SCMERR);
}
/*******************************************************
*** I N T E G E R B Y T E - S W A P P I N G ***
*******************************************************/
union intchar {
int ui;
char uc[sizeof(int)];
};
int byteswap (in)
int in;
{
union intchar x,y;
register int ix,iy;
if (swapmode == 0) return (in);
x.ui = in;
iy = sizeof(int);
for (ix=0; ix<sizeof(int); ix++) {
--iy;
y.uc[iy] = x.uc[ix];
}
return (y.ui);
}