Fix the signal races in rbootd.

Credit to millert@ and deraadt@ for pointing out some of my braindamage.

3 files changed, 84 insertions, 77 deletions

diff --git a/usr.sbin/rbootd/bpf.c b/usr.sbin/rbootd/bpf.c
index 3c669c51c84..df1a31282d1 100644
--- a/usr.sbin/rbootd/bpf.c
+++ b/usr.sbin/rbootd/bpf.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bpf.c,v 1.5 2001/01/17 00:33:03 pjanzen Exp $	*/
+/*	$OpenBSD: bpf.c,v 1.6 2002/02/19 21:04:09 miod Exp $	*/
 /*	$NetBSD: bpf.c,v 1.5.2.1 1995/11/14 08:45:42 thorpej Exp $	*/
 
 /*
@@ -49,7 +49,7 @@
 
 #ifndef lint
 /*static char sccsid[] = "@(#)bpf.c	8.1 (Berkeley) 6/4/93";*/
-static char rcsid[] = "$OpenBSD: bpf.c,v 1.5 2001/01/17 00:33:03 pjanzen Exp $";
+static char rcsid[] = "$OpenBSD: bpf.c,v 1.6 2002/02/19 21:04:09 miod Exp $";
 #endif /* not lint */
 
 #include <sys/param.h>
@@ -103,7 +103,7 @@ BpfOpen()
 
 	if (BpfFd < 0) {
 		syslog(LOG_ERR, "bpf: no available devices: %m");
-		Exit(0);
+		DoExit();
 	}
 
 	/*
@@ -113,7 +113,7 @@ BpfOpen()
 	(void) strncpy(ifr.ifr_name, IntfName, sizeof(ifr.ifr_name));
 	if (ioctl(BpfFd, BIOCSETIF, (caddr_t)&ifr) < 0) {
 		syslog(LOG_ERR, "bpf: ioctl(BIOCSETIF,%s): %m", IntfName);
-		Exit(0);
+		DoExit();
 	}
 
 	/*
@@ -121,12 +121,12 @@ BpfOpen()
 	 */
 	if (ioctl(BpfFd, BIOCGDLT, (caddr_t)&n) < 0) {
 		syslog(LOG_ERR, "bpf: ioctl(BIOCGDLT): %m");
-		Exit(0);
+		DoExit();
 	}
 	if (n != DLT_EN10MB) {
 		syslog(LOG_ERR,"bpf: %s: data-link type %d unsupported",
 		       IntfName, n);
-		Exit(0);
+		DoExit();
 	}
 
 	/*
@@ -135,7 +135,7 @@ BpfOpen()
 	n = 1;
 	if (ioctl(BpfFd, BIOCIMMEDIATE, (caddr_t)&n) < 0) {
 		syslog(LOG_ERR, "bpf: ioctl(BIOCIMMEDIATE): %m");
-		Exit(0);
+		DoExit();
 	}
 
 	/*
@@ -155,7 +155,7 @@ BpfOpen()
 
 		if (ioctl(BpfFd, BIOCPROMISC, (caddr_t)0) < 0) {
 			syslog(LOG_ERR, "bpf: can't set promiscuous mode: %m");
-			Exit(0);
+			DoExit();
 		}
 	}
 
@@ -164,7 +164,7 @@ BpfOpen()
 	 */
 	if (ioctl(BpfFd, BIOCGBLEN, (caddr_t)&BpfLen) < 0) {
 		syslog(LOG_ERR, "bpf: ioctl(BIOCGBLEN): %m");
-		Exit(0);
+		DoExit();
 	}
 	if (BpfPkt == NULL)
 		BpfPkt = (u_int8_t *)malloc(BpfLen);
@@ -172,7 +172,7 @@ BpfOpen()
 	if (BpfPkt == NULL) {
 		syslog(LOG_ERR, "bpf: out of memory (%u bytes for bpfpkt)",
 		       BpfLen);
-		Exit(0);
+		DoExit();
 	}
 
 	/*
@@ -198,7 +198,7 @@ BpfOpen()
 
 		if (ioctl(BpfFd, BIOCSETF, (caddr_t)&bpf_pgm) < 0) {
 			syslog(LOG_ERR, "bpf: ioctl(BIOCSETF): %m");
-			Exit(0);
+			DoExit();
 		}
 	}
 
@@ -391,40 +391,3 @@ BpfWrite(rconn)
 
 	return(1);
 }
-
-/*
-**  BpfClose -- Close a BPF device.
-**
-**	Parameters:
-**		None.
-**
-**	Returns:
-**		Nothing.
-**
-**	Side Effects:
-**		None.
-*/
-void
-BpfClose()
-{
-	struct ifreq ifr;
-
-	if (BpfPkt != NULL) {
-		free((char *)BpfPkt);
-		BpfPkt = NULL;
-	}
-
-	if (BpfFd == -1)
-		return;
-
-#ifdef MSG_EOR
-	ifr.ifr_addr.sa_len = RMP_ADDRLEN + 2;
-#endif
-	ifr.ifr_addr.sa_family = AF_UNSPEC;
-	bcopy(&RmpMcastAddr[0], (char *)&ifr.ifr_addr.sa_data[0], RMP_ADDRLEN);
-	if (ioctl(BpfFd, SIOCDELMULTI, (caddr_t)&ifr) < 0)
-		(void) ioctl(BpfFd, BIOCPROMISC, (caddr_t)0);
-
-	(void) close(BpfFd);
-	BpfFd = -1;
-}
diff --git a/usr.sbin/rbootd/defs.h b/usr.sbin/rbootd/defs.h
index 7eba93dedd7..1743ea76602 100644
--- a/usr.sbin/rbootd/defs.h
+++ b/usr.sbin/rbootd/defs.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: defs.h,v 1.4 2002/02/16 21:28:08 millert Exp $	*/
+/*	$OpenBSD: defs.h,v 1.5 2002/02/19 21:04:09 miod Exp $	*/
 /*	$NetBSD: defs.h,v 1.5 1995/10/06 05:12:14 thorpej Exp $	*/
 
 /*
@@ -152,18 +152,13 @@ extern	u_int8_t RmpMcastAddr[];	/* RMP multicast address */
 
 void	 AddConn(RMPCONN *);
 int	 BootDone(RMPCONN *);
-void	 BpfClose(void);
 char	*BpfGetIntfName(char **);
 int	 BpfOpen(void);
 int	 BpfRead(RMPCONN *, int);
 int	 BpfWrite(RMPCONN *);
-void	 DebugOff(int);
-void	 DebugOn(int);
 void	 DispPkt(RMPCONN *, int);
-void	 DoTimeout(void);
+void	 DoExit(void);
 void	 DspFlnm(u_int, char *);
-void	 Exit(int);
-CLIENT	*FindClient(RMPCONN *);
 RMPCONN	*FindConn(RMPCONN *);
 void	 FreeClients(void);
 void	 FreeConn(RMPCONN *);
@@ -176,7 +171,6 @@ char	*NewStr(char *);
 u_int8_t *ParseAddr(char *);
 int	 ParseConfig(void);
 void	 ProcessPacket(RMPCONN *, CLIENT *);
-void	 ReConfig(int);
 void	 RemoveConn(RMPCONN *);
 int	 SendBootRepl(struct rmp_packet *, RMPCONN *, char *[]);
 int	 SendFileNo(struct rmp_packet *, RMPCONN *, char *[]);
diff --git a/usr.sbin/rbootd/rbootd.c b/usr.sbin/rbootd/rbootd.c
index ce990cebcdd..424b38a8e72 100644
--- a/usr.sbin/rbootd/rbootd.c
+++ b/usr.sbin/rbootd/rbootd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: rbootd.c,v 1.10 2002/02/19 18:38:02 mpech Exp $	*/
+/*	$OpenBSD: rbootd.c,v 1.11 2002/02/19 21:04:09 miod Exp $	*/
 /*	$NetBSD: rbootd.c,v 1.5 1995/10/06 05:12:17 thorpej Exp $	*/
 
 /*
@@ -55,7 +55,7 @@ static char copyright[] =
 
 #ifndef lint
 /*static char sccsid[] = "@(#)rbootd.c	8.1 (Berkeley) 6/4/93";*/
-static char rcsid[] = "$OpenBSD: rbootd.c,v 1.10 2002/02/19 18:38:02 mpech Exp $";
+static char rcsid[] = "$OpenBSD: rbootd.c,v 1.11 2002/02/19 21:04:09 miod Exp $";
 #endif /* not lint */
 
 #include <sys/param.h>
@@ -74,6 +74,22 @@ static char rcsid[] = "$OpenBSD: rbootd.c,v 1.10 2002/02/19 18:38:02 mpech Exp $
 
 extern	char *__progname;	/* from crt0.o */
 
+volatile sig_atomic_t	dodebugoff;
+volatile sig_atomic_t	dodebugon;
+volatile sig_atomic_t	doreconfig;
+
+void DebugOff(int);
+void DebugOn(int);
+void ReConfig(int);
+void Exit(int);
+
+void DoDebugOff(void);
+void DoDebugOn(void);
+void DoReConfig(void);
+
+void DoTimeout(void);
+CLIENT *FindClient(RMPCONN *);
+
 int
 main(argc, argv)
 	int argc;
@@ -155,7 +171,7 @@ main(argc, argv)
 			syslog(LOG_NOTICE, "restarted (??)");
 			/* BpfGetIntfName() returns safe names, using %m */
 			syslog(LOG_ERR, "%s", errmsg);
-			Exit(0);
+			DoExit();
 		}
 	}
 
@@ -170,7 +186,7 @@ main(argc, argv)
 	 */
 	if (gethostname(MyHost, sizeof(MyHost)) < 0) {
 		syslog(LOG_ERR, "gethostname: %m");
-		Exit(0);
+		DoExit();
 	}
 	MyHost[MAXHOSTNAMELEN] = '\0';
 
@@ -187,7 +203,7 @@ main(argc, argv)
 	 */
 	if (chdir(BootDir) < 0) {
 		syslog(LOG_ERR, "chdir: %m (%s)", BootDir);
-		Exit(0);
+		DoExit();
 	}
 
 	/*
@@ -197,13 +213,13 @@ main(argc, argv)
 	sigaddset(&hmask, SIGHUP);
 	sigprocmask(SIG_BLOCK, &hmask, &omask);	/* prevent reconfig's */
 	if (GetBootFiles() == 0)		/* get list of boot files */
-		Exit(0);
+		DoExit();
 	if (ParseConfig() == 0)			/* parse config file */
-		Exit(0);
+		DoExit();
 
 	/*
 	 *  Open and initialize a BPF device for the appropriate interface.
-	 *  If an error is encountered, a message is displayed and Exit()
+	 *  If an error is encountered, a message is displayed and DoExit()
 	 *  is called.
 	 */
 	fd = BpfOpen();
@@ -222,6 +238,22 @@ main(argc, argv)
 		fd_set r;
 		int nsel;
 
+		/*
+		 * Check pending actions
+		 */
+		if (dodebugoff) {
+			DoDebugOff();
+			dodebugoff = 0;
+		}
+		if (dodebugon) {
+			DoDebugOn();
+			dodebugon = 0;
+		}
+		if (doreconfig) {
+			DoReConfig();
+			doreconfig = 0;
+		}
+
 		r = rset;
 
 		if (RmpConns == NULL) {		/* timeout isnt necessary */
@@ -236,7 +268,7 @@ main(argc, argv)
 			if (errno == EINTR)
 				continue;
 			syslog(LOG_ERR, "select: %m");
-			Exit(0);
+			DoExit();
 		} else if (nsel == 0) {		/* timeout */
 			DoTimeout();			/* clear stale conns */
 			continue;
@@ -316,7 +348,7 @@ DoTimeout()
 **  FindClient -- Find client associated with a packet.
 **
 **	Parameters:
-**		rconn - the new packet. 
+**		rconn - the new packet.
 **
 **	Returns:
 **		Pointer to client info if found, NULL otherwise.
@@ -359,12 +391,16 @@ void
 Exit(sig)
 	int sig;
 {
-	/* XXX race */
-	if (sig > 0)
-		syslog(LOG_ERR, "going down on signal %d", sig);
-	else
-		syslog(LOG_ERR, "going down with fatal error");
-	BpfClose();
+	struct syslog_data sdata = SYSLOG_DATA_INIT;
+
+	syslog_r(LOG_ERR, &sdata, "going down on signal %d", sig);
+	_exit(1);
+}
+
+void
+DoExit()
+{
+	syslog(LOG_ERR, "going down on fatal error");
 	exit(1);
 }
 
@@ -389,16 +425,21 @@ void
 ReConfig(signo)
 	int signo;
 {
-	/* XXX race */
+	doreconfig = 1;
+}
+
+void
+DoReConfig()
+{
 	syslog(LOG_NOTICE, "reconfiguring boot server");
 
 	FreeConns();
 
 	if (GetBootFiles() == 0)
-		Exit(0);
+		DoExit();
 
 	if (ParseConfig() == 0)
-		Exit(0);
+		DoExit();
 }
 
 /*
@@ -417,8 +458,12 @@ void
 DebugOff(signo)
 	int signo;
 {
-	/* XXX race */
+	dodebugoff = 1;
+}
 
+void
+DoDebugOff()
+{
 	if (DbgFp != NULL)
 		(void) fclose(DbgFp);
 
@@ -442,7 +487,12 @@ void
 DebugOn(signo)
 	int signo;
 {
-	/* XXX race */
+	dodebugon = 1;
+}
+
+void
+DoDebugOn()
+{
 	if (DbgFp == NULL) {
 		if ((DbgFp = fopen(DbgFile, "w")) == NULL)
 			syslog(LOG_ERR, "can't open debug file (%s)", DbgFile);