Replace emulated versions of setreuid() and setregid() with real syscalls.

These are spec'd by POSIX as of 1003.1-2001; deraadt@ OK

6 files changed, 103 insertions, 187 deletions

diff --git a/lib/libc/compat-43/Makefile.inc b/lib/libc/compat-43/Makefile.inc
index 1bf6ec18537..ffd0419b575 100644
--- a/lib/libc/compat-43/Makefile.inc
+++ b/lib/libc/compat-43/Makefile.inc
@@ -1,12 +1,12 @@
-#	$OpenBSD: Makefile.inc,v 1.5 2002/10/30 20:15:29 millert Exp $
+#	$OpenBSD: Makefile.inc,v 1.6 2003/01/31 21:47:45 millert Exp $
 
 # compat-43 sources
 .PATH: ${LIBCSRCDIR}/arch/${MACHINE_ARCH}/compat-43 ${LIBCSRCDIR}/compat-43
 
 SRCS+=	creat.c getdtablesize.c gethostid.c getwd.c killpg.c sethostid.c \
-	setpgrp.c setregid.c setreuid.c setrgid.c setruid.c sigcompat.c
+	setpgrp.c setrgid.c setruid.c sigcompat.c
 
-MAN+=	creat.3 getdtablesize.3 gethostid.3 killpg.3 setregid.3 setreuid.3 \
+MAN+=	creat.3 getdtablesize.3 gethostid.3 killpg.3 \
 	setruid.3 sigblock.3 sigpause.3 sigsetmask.3 sigvec.3
 
 MLINKS+=setruid.3 setrgid.3
diff --git a/lib/libc/compat-43/setregid.c b/lib/libc/compat-43/setregid.c
deleted file mode 100644
index 084b049a369..00000000000
--- a/lib/libc/compat-43/setregid.c
+++ /dev/null
@@ -1,67 +0,0 @@
-/*
- * Copyright (c) 1982, 1986, 1989, 1990, 1991 Regents of the University
- * of California.  All rights reserved.
- *
- * 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.
- */
-
-#if defined(LIBC_SCCS) && !defined(lint)
-static char *rcsid = "$OpenBSD: setregid.c,v 1.5 2002/10/30 20:15:29 millert Exp $";
-#endif /* LIBC_SCCS and not lint */
-
-#include <sys/types.h>
-#include <unistd.h>
-
-#ifndef NO_WARN_REFERENCES
-__warn_references(setregid, "warning: this program uses setregid(), which is deprecated.");
-#endif
-
-int
-setregid(gid_t rgid, gid_t egid)
-{
-	int error;
-	gid_t sgid, cur_rgid, cur_egid, cur_sgid;
-
-	if (error == (getresgid(&cur_rgid, &cur_egid, &cur_sgid)) != 0)
-		return (error);
-
-	/*
-	 * The saved gid presents a bit of a dilemma, as it did not
-	 * appear in 4.3BSD.  We only set the saved gid when the real
-	 * gid is specified and either its value would change, or,
-	 * where the saved and effective gids are different.
-	 */
-	if (rgid != (gid_t)-1 && (rgid != cur_rgid ||
-	    cur_sgid != (egid != (gid_t)-1 ? egid : cur_egid)))
-		sgid = rgid;
-	else
-		sgid = (gid_t)-1;
-
-	return (setresgid(rgid, egid, sgid));
-}
diff --git a/lib/libc/compat-43/setreuid.c b/lib/libc/compat-43/setreuid.c
deleted file mode 100644
index 5da47c8e1f3..00000000000
--- a/lib/libc/compat-43/setreuid.c
+++ /dev/null
@@ -1,65 +0,0 @@
-/*
- * Copyright (c) 1982, 1986, 1989, 1990, 1991 Regents of the University
- * of California.  All rights reserved.
- *
- * 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.
- */
-
-#if defined(LIBC_SCCS) && !defined(lint)
-static char *rcsid = "$OpenBSD: setreuid.c,v 1.6 2002/10/30 20:15:29 millert Exp $";
-#endif /* LIBC_SCCS and not lint */
-
-#include <sys/types.h>
-#include <unistd.h>
-
-__warn_references(setreuid, "warning: this program uses setreuid(), which is deprecated.");
-
-int
-setreuid(uid_t ruid, uid_t euid)
-{
-	int error;
-	uid_t suid, cur_ruid, cur_euid, cur_suid;
-
-	if (error == (getresuid(&cur_ruid, &cur_euid, &cur_suid)) != 0)
-		return (error);
-
-	/*
-	 * The saved uid presents a bit of a dilemma, as it did not
-	 * appear in 4.3BSD.  We only set the saved uid when the real
-	 * uid is specified and either its value would change, or,
-	 * where the saved and effective uids are different.
-	 */
-	if (ruid != (uid_t)-1 && (ruid != cur_ruid ||
-	    cur_suid != (euid != (uid_t)-1 ? euid : cur_euid)))
-		suid = ruid;
-	else
-		suid = (uid_t)-1;
-
-	return (setresuid(ruid, euid, suid));
-}
diff --git a/lib/libc/sys/Makefile.inc b/lib/libc/sys/Makefile.inc
index 195534ecdb2..e6030715104 100644
--- a/lib/libc/sys/Makefile.inc
+++ b/lib/libc/sys/Makefile.inc
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.inc,v 1.63 2002/12/02 15:54:14 millert Exp $
+#	$OpenBSD: Makefile.inc,v 1.64 2003/01/31 21:47:46 millert Exp $
 #	$NetBSD: Makefile.inc,v 1.35 1995/10/16 23:49:07 jtc Exp $
 #	@(#)Makefile.inc	8.1 (Berkeley) 6/17/93
 
@@ -51,8 +51,8 @@ ASM=	accept.o access.o acct.o adjtime.o bind.o chdir.o chflags.o chmod.o \
 	read.o readlink.o readv.o reboot.o recvfrom.o recvmsg.o rename.o \
 	revoke.o rmdir.o select.o semget.o semop.o sendmsg.o sendto.o \
 	setegid.o seteuid.o setgid.o setgroups.o setitimer.o setpgid.o \
-	setpriority.o setresgid.o setresuid.o setrlimit.o setsid.o \
-	setsockopt.o settimeofday.o \
+	setpriority.o setregid.o setreuid.o setresgid.o setresuid.o \
+	setrlimit.o setsid.o setsockopt.o settimeofday.o \
 	setuid.o shmat.o shmctl.o shmdt.o shmget.o shutdown.o sigaction.o \
 	sigaltstack.o socket.o socketpair.o stat.o statfs.o swapon.o swapctl.o \
 	symlink.o sync.o sysarch.o umask.o undelete.o unlink.o unmount.o \
@@ -222,11 +222,11 @@ MAN+=	accept.2 access.2 acct.2 adjtime.2 bind.2 brk.2 chdir.2 chflags.2 \
 	nfssvc.2 open.2 pathconf.2 \
 	pipe.2 profil.2 poll.2 ptrace.2 quotactl.2 read.2 readlink.2 reboot.2 \
 	recv.2 rename.2 revoke.2 rfork.2 rmdir.2 select.2 send.2 setgroups.2 \
-	setpgid.2 setresuid.2 setsid.2 setuid.2 shutdown.2 sigaction.2 \
-	sigaltstack.2 sigpending.2 sigprocmask.2 sigreturn.2 sigstack.2 \
-	sigsuspend.2 socket.2 socketpair.2 stat.2 statfs.2 swapctl.2 symlink.2 \
-	sync.2 sysarch.2 syscall.2 truncate.2 umask.2 unlink.2 utimes.2 \
-	vfork.2 wait.2 write.2
+	setpgid.2 setregid.2 setreuid.2 setresuid.2 setsid.2 setuid.2 \
+	shutdown.2 sigaction.2 sigaltstack.2 sigpending.2 sigprocmask.2 \
+	sigreturn.2 sigstack.2 sigsuspend.2 socket.2 socketpair.2 stat.2 \
+	statfs.2 swapctl.2 symlink.2 sync.2 sysarch.2 syscall.2 truncate.2 \
+	umask.2 unlink.2 utimes.2 vfork.2 wait.2 write.2
 
 MAN+=	extattr_get_file.2
 MLINKS+=extattr_get_file.2 extattr_set_file.2 \
diff --git a/lib/libc/compat-43/setregid.3 b/lib/libc/sys/setregid.2
index f4f7e472970..adedd38c189 100644
--- a/lib/libc/compat-43/setregid.3
+++ b/lib/libc/sys/setregid.2
@@ -1,5 +1,7 @@
-.\" Copyright (c) 1983, 1991 The Regents of the University of California.
-.\" All rights reserved.
+.\" $OpenBSD: setregid.2,v 1.1 2003/01/31 21:47:46 millert Exp $
+.\"
+.\" Copyright (c) 1980, 1991, 1993, 1994
+.\"	The Regents of the University of California.  All rights reserved.
 .\"
 .\" Redistribution and use in source and binary forms, with or without
 .\" modification, are permitted provided that the following conditions
@@ -29,10 +31,10 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.\"	$OpenBSD: setregid.3,v 1.9 2002/10/30 20:18:41 millert Exp $
+.\"     @(#)setregid.2	8.2 (Berkeley) 4/16/94
 .\"
-.Dd March 10, 1991
-.Dt SETREGID 3
+.Dd January 29, 2003
+.Dt SETREGID 2
 .Os
 .Sh NAME
 .Nm setregid
@@ -40,36 +42,37 @@
 .Sh SYNOPSIS
 .Fd #include <unistd.h>
 .Ft int
-.Fn setregid "int rgid" "int egid"
+.Fn setregid "gid_t rgid" "gid_t egid"
 .Sh DESCRIPTION
 The real and effective group IDs of the current process
-are set to the arguments.
-Unprivileged users may change the real group
-ID to the effective group ID and vice-versa; only the superuser may
-make other changes.
+are set according to the arguments.
+If the real group ID is changed, the saved group ID is changed to the
+new value of the effective group ID.
+.Pp
+Unprivileged users may change either group ID to the current value
+of the real, effective, or saved group ID.
+Only the superuser may make other changes.
 .Pp
-Supplying a value of \-1 for either the real or effective
+Supplying a value of -1 for either the real or effective
 group ID forces the system to substitute the current
-ID in place of the \-1 parameter.
+ID in place of the -1 parameter.
 .Pp
 The
 .Fn setregid
 function was intended to allow swapping the real and
 effective group IDs in set-group-ID programs to temporarily relinquish
 the set-group-ID value.
-This function did not work correctly, and its
-purpose is now better served by the use of the
+This purpose is now better served by the use of the
 .Fn setegid
 function (see
 .Xr setuid 2 ) .
 .Pp
 When setting the real and effective group IDs to the same value, the
-standard
 .Fn setgid
 function is preferred.
 .Sh RETURN VALUES
 Upon successful completion, a value of 0 is returned.
-Otherwise, a value of \-1 is returned and
+Otherwise, a value of -1 is returned and
 .Va errno
 is set to indicate the error.
 .Sh ERRORS
@@ -88,17 +91,35 @@ was specified.
 .Sh STANDARDS
 The
 .Fn setregid
-function is not a part of the
+function conforms to the
+.St -p1003.1-01
+and
+.St -xpg4.3 .
+specifications.
+.Pp
+Note, however, that prior to
+.St -p1003.1-01 ,
+the
+.Fn setregid
+function was not a part of the
 .St -p1003.1
-specification and should not be used where portability is desired.
+specification.
+As a result, it may not be implemented on all systems.
 .Sh HISTORY
 The
 .Fn setregid
-function call first appeared in
+function call appeared in
 .Bx 4.2 .
 A semantically different version appeared in
 .Bx 4.4 .
-The current version, with the old semantics restored, is implemented via the
-.Xr setresgid 2
-function which first appeared in
+The current version, with the original semantics restored, appeared in
 .Ox 3.3 .
+.Sh CAVEATS
+The
+.Fn setregid
+function predates
+.Tn POSIX
+saved group IDs.
+This implementation changes the saved group ID to the new value of
+the effective group ID if the real group ID is changed.
+Other implementations may behave differently.
diff --git a/lib/libc/compat-43/setreuid.3 b/lib/libc/sys/setreuid.2
index 5ac64445fc2..60df37991a3 100644
--- a/lib/libc/compat-43/setreuid.3
+++ b/lib/libc/sys/setreuid.2
@@ -1,5 +1,5 @@
-.\" Copyright (c) 1980, 1991 The Regents of the University of California.
-.\" All rights reserved.
+.\" Copyright (c) 1980, 1991, 1993, 1994
+.\"	The Regents of the University of California.  All rights reserved.
 .\"
 .\" Redistribution and use in source and binary forms, with or without
 .\" modification, are permitted provided that the following conditions
@@ -29,10 +29,10 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.\"	$OpenBSD: setreuid.3,v 1.9 2002/10/30 20:18:41 millert Exp $
+.\"      @(#)setreuid.2	8.2 (Berkeley) 4/16/94
 .\"
-.Dd March 10, 1991
-.Dt SETREUID 3
+.Dd January 29, 2003
+.Dt SETREUID 2
 .Os
 .Sh NAME
 .Nm setreuid
@@ -40,35 +40,38 @@
 .Sh SYNOPSIS
 .Fd #include <unistd.h>
 .Ft int
-.Fn setreuid "int ruid" "int euid"
+.Fn setreuid "uid_t ruid" "uid_t euid"
 .Sh DESCRIPTION
 The real and effective user IDs of the
 current process are set according to the arguments.
-If
-.Fa ruid
-or
-.Fa euid
-is \-1, the current UID is filled in by the system.
-Unprivileged users may change the real user
-ID to the effective user ID and vice-versa; only the superuser may
-make other changes.
+If the real user ID is changed, or the effective user ID is changed
+to a value other than the real user ID, then the saved user ID will
+be set to the effective user ID.
+.Pp
+Unprivileged users may change either user ID to the current value
+of the real, effective, or saved user ID.
+Only the superuser may make other changes.
+.Pp
+Supplying a value of -1 for either the real or effective
+user ID forces the system to substitute the current
+ID in place of the -1 parameter.
 .Pp
 The
 .Fn setreuid
-function has been used to swap the real and effective user
-IDs in set-user-ID programs to temporarily relinquish the set-user-ID
-value.
+function was intended to allow swapping the real and
+effective user IDs in set-user-ID programs to temporarily relinquish
+the set-user-ID value.
 This purpose is now better served by the use of the
 .Fn seteuid
 function (see
 .Xr setuid 2 ) .
 .Pp
-When setting the real and effective user IDs to the same value, the standard
+When setting the real and effective user IDs to the same value, the
 .Fn setuid
 function is preferred.
 .Sh RETURN VALUES
 Upon successful completion, a value of 0 is returned.
-Otherwise, a value of \-1 is returned and
+Otherwise, a value of -1 is returned and
 .Va errno
 is set to indicate the error.
 .Sh ERRORS
@@ -83,6 +86,23 @@ was specified.
 .Xr seteuid 2 ,
 .Xr setresuid 2 ,
 .Xr setuid 2
+.Sh STANDARDS
+The
+.Fn setreuid
+function conforms to the
+.St -p1003.1-01
+and
+.St -xpg4.3 .
+specifications.
+.Pp
+Note, however, that prior to
+.St -p1003.1-01 ,
+the
+.Fn setreuid
+function was not a part of the
+.St -p1003.1
+specification.
+As a result, it may not be implemented on all systems.
 .Sh HISTORY
 The
 .Fn setreuid
@@ -90,7 +110,14 @@ function call appeared in
 .Bx 4.2 .
 A semantically different version appeared in
 .Bx 4.4 .
-The current version, with the old semantics restored, is implemented via the
-.Xr setresuid 2
-function which first appeared in
+The current version, with the original semantics restored, appeared in
 .Ox 3.3 .
+.Sh CAVEATS
+The
+.Fn setreuid
+function predates
+.Tn POSIX   
+saved user IDs.
+This implementation changes the saved user ID to the new value of
+the effective user ID if the real user ID is changed.
+Other implementations may behave differently.