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Remove the suser(9) interface from the kernel. It has been replaced from

Browse source 
years by the priv_check(9) interface and just very few places are left.
Note that compatibility stub with older FreeBSD version
(all above the 8 limit though) are left in order to reduce diffs against
old versions. It is responsibility of the maintainers for any module, if
they think it is the case, to axe out such cases.

This patch breaks KPI so __FreeBSD_version will be bumped into a later
commit.

This patch needs to be credited 50-50 with rwatson@ as he found time to
explain me how the priv_check() works in detail and to review patches.

Tested by:      Giovanni Trematerra <giovanni dot trematerra at gmail dot com>
Reviewed by:    rwatson
This commit is contained in:
Attilio Rao 2008-09-17 15:49:44 +00:00
parent a56f84cf2c
commit cecd8edba5
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=183113
12 changed files with 46 additions and 171 deletions
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2
ObsoleteFiles.inc
View file

@ -14,6 +14,8 @@
# The file is partitioned: OLD_FILES first, then OLD_LIBS and OLD_DIRS last.
#
# 20080917: removal of manpage for axed kernel primitive suser(9)
OLD_FILES+=usr/share/man/man9/suser.9
# 20080913: pax removed from rescue
OLD_FILES+=rescue/pax
# 20080823: removal of unneeded pt_chown, to implement grantpt(3)

2
share/man/man9/Makefile
View file

@ -225,7 +225,6 @@ MAN= accept_filter.9 \
stack.9 \
store.9 \
style.9 \
suser.9 \
swi.9 \
sx.9 \
SYSCALL_MODULE.9 \
@ -1108,7 +1107,6 @@ MLINKS+=store.9 subyte.9 \
store.9 suswintr.9 \
store.9 susword.9 \
store.9 suword.9
MLINKS+=suser.9 suser_cred.9
MLINKS+=swi.9 swi_add.9 \
swi.9 swi_sched.9
MLINKS+=sx.9 sx_assert.9 \

3
share/man/man9/priv.9
View file

@ -48,7 +48,7 @@ passed thread,
.Fa td ,
or credential,
.Fa cred .
This interface replaces the
This interface replaces the now removed
.Xr suser 9
privilege checking interface.
Privileges typically represent rights in one of two categories: the right to
@ -112,7 +112,6 @@ failure occurred.
.Sh SEE ALSO
.Xr jail 2 ,
.Xr mac 9 ,
.Xr suser 9 ,
.Xr ucred 9
.Sh AUTHORS
The

115
share/man/man9/suser.9
View file

@ -1,115 +0,0 @@
.\"
.\" Copyright (c) 1996 Julian R Elischer
.\" All rights reserved.
.\"
.\" This code is derived from software contributed by Kenneth Stailey.
.\"
.\" 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. The name of the author may not be used to endorse or promote products
.\" derived from this software without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
.\"
.\" $FreeBSD$
.\"
.Dd August 30, 2007
.Dt SUSER 9
.Os
.Sh NAME
.Nm suser ,
.Nm suser_cred
.Nd check if credentials have superuser privileges
.Sh SYNOPSIS
.In sys/priv.h
.Ft int
.Fn suser "struct thread *td"
.Ft int
.Fn suser_cred "struct ucred *cred" "int flag"
.Sh DESCRIPTION
The
.Fn suser
and
.Fn suser_cred
functions check if the credentials given include superuser powers.
.Pp
These interfaces have now been obsoleted by
.Xr priv 9 ,
and are provided only for compatibility with third party kernel modules that
have not yet been updated to the new interface.
They should not be used in any new kernel code.
.Pp
The
.Fn suser
function is the most common, and should be used unless special
circumstances dictate otherwise.
.Pp
The
.Fn suser_cred
function should be used when the credentials to be checked are
not the thread's own, when there is no thread, when superuser
powers should be extended to imprisoned roots, or when the credential
to be checked is the real user rather than the effective user.
.Pp
Whether or not a privilege is permitted in a
.Xr jail 8
depends on logic in
.Fn prison_priv_check .
.Pp
In general, privileges are assigned based on the effective user ID; in some
cases, the real user ID may be used.
.Pp
The
.Fa flags
field is currently unused.
.Pp
The
.Fn suser
and
.Fn suser_cred
functions note the fact that superuser powers have been used in the
process structure of the process specified.
Because part of their function is to notice
whether superuser powers have been used,
the functions should only be called after other permission
possibilities have been exhausted.
.Sh RETURN VALUES
The
.Fn suser
and
.Fn suser_cred
functions return 0 if the user has superuser powers and
.Er EPERM
otherwise.
This is the
.Em reverse logic
of some other implementations of
.Fn suser
in which a TRUE response indicates superuser powers.
.Sh SEE ALSO
.Xr chroot 2 ,
.Xr jail 2 ,
.Xr priv 9
.Sh BUGS
The
.Fn suser
and
.Fn suser_cred
functions do not, in fact, record that superuser privileges have been
used, and have not done so since August 2000.

6
share/man/man9/ucred.9
View file

@ -163,12 +163,6 @@ In these circumstances, the thread credential
should be used, as it requires no locking to access safely, and remains stable
for the duration of the call even in the face of a multi-threaded
application changing the process credentials from another thread.
Primitives such as
.Xr suser 9
will assume the use of
.Va td_ucred
unless explicitly specified using
.Xr suser_cred 9 .
.Pp
During a process credential update, the process lock must be held across
check and update, to prevent race conditions.

5
share/man/man9/vfs_suser.9
View file

@ -46,7 +46,7 @@ It will check to see if the thread
passed in has the same credentials as the user that mounted the
file system.
If so, it returns 0, otherwise it returns what
.Xr suser 9
.Xr priv_check 9
would have returned.
.Sh RETURN VALUES
The
@ -61,8 +61,7 @@ of some other implementations of
in which a TRUE response indicates superuser powers.
.Sh SEE ALSO
.Xr chroot 2 ,
.Xr jail 2 ,
.Xr suser 9
.Xr jail 2
.Sh HISTORY
The
.Fn vfs_suser

4
sys/dev/cxgb/ulp/tom/cxgb_cpl_io.c
View file

@ -1663,8 +1663,8 @@ t3_ip_ctloutput(struct socket *so, struct sockopt *sopt)
if (error)
return (error);
if (optval > IPTOS_PREC_CRITIC_ECP && !suser(curthread))
return (EPERM);
if (optval > IPTOS_PREC_CRITIC_ECP)
return (EINVAL);
inp = so_sotoinpcb(so);
inp_wlock(inp);

21
sys/kern/kern_priv.c
View file

@ -133,24 +133,3 @@ priv_check(struct thread *td, int priv)
return (priv_check_cred(td->td_ucred, priv, 0));
}
/*
* Historical suser() wrapper functions, which now simply request PRIV_ROOT.
* These will be removed in the near future, and exist solely because
* the kernel and modules are not yet fully adapted to the new model.
*/
int
suser_cred(struct ucred *cred, int flags)
{
return (priv_check_cred(cred, PRIV_ROOT, flags));
}
int
suser(struct thread *td)
{
KASSERT(td == curthread, ("suser: td != curthread"));
return (suser_cred(td->td_ucred, 0));
}

15
sys/netipx/ipx.c
View file

@ -99,7 +99,7 @@ ipx_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp,
struct ifaddr *ifa;
struct ipx_ifaddr *oia;
int dstIsNew, hostIsNew;
int error = 0;
int error = 0, priv;
/*
* Find address for this interface, if it exists.
@ -135,12 +135,13 @@ ipx_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp,
return (0);
}
if (td && (error = suser(td)) != 0)
return (error);
switch (cmd) {
case SIOCAIFADDR:
case SIOCDIFADDR:
priv = (cmd == SIOCAIFADDR) ? PRIV_NET_ADDIFADDR :
PRIV_NET_DELIFADDR;
if (td && (error = priv_check(td, priv)) != 0)
return (error);
if (ifra->ifra_addr.sipx_family == AF_IPX)
for (oia = ia; ia != NULL; ia = ia->ia_next) {
if (ia->ia_ifp == ifp &&
@ -154,6 +155,8 @@ ipx_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp,
case SIOCSIFADDR:
case SIOCSIFDSTADDR:
if (td && (error = priv_check(td, PRIV_NET_SETLLADDR)) != 0)
return (error);
if (ia == NULL) {
oia = (struct ipx_ifaddr *)
malloc(sizeof(*ia), M_IFADDR,
@ -183,6 +186,10 @@ ipx_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp,
ia->ia_broadaddr.sipx_addr.x_host = ipx_broadhost;
}
}
break;
default:
if (td && (error = priv_check(td, PRIV_NET_HWIOCTL)) != 0)
return (error);
}
switch (cmd) {

6
sys/nfsserver/nfs_serv.c
View file

@ -1802,7 +1802,8 @@ nfsrv_create(struct nfsrv_descript *nfsd, struct nfssvc_sock *slp,
if (vap->va_type == VCHR && rdev == 0xffffffff)
vap->va_type = VFIFO;
if (vap->va_type != VFIFO &&
(error = suser_cred(cred, 0))) {
(error = priv_check_cred(cred, PRIV_VFS_MKNOD_DEV,
0))) {
goto ereply;
}
vap->va_rdev = rdev;
@ -2024,7 +2025,8 @@ nfsrv_mknod(struct nfsrv_descript *nfsd, struct nfssvc_sock *slp,
if (error)
NDFREE(&nd, NDF_ONLY_PNBUF);
} else {
if (vtyp != VFIFO && (error = suser_cred(cred, 0)))
if (vtyp != VFIFO && (error = priv_check_cred(cred,
PRIV_VFS_MKNOD_DEV, 0)))
goto out;
error = VOP_MKNOD(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, vap);
if (error) {

32
sys/security/mac_bsdextended/mac_bsdextended.c
View file

@ -221,7 +221,7 @@ static int
ugidfw_rulecheck(struct mac_bsdextended_rule *rule,
struct ucred *cred, struct vnode *vp, struct vattr *vap, int acc_mode)
{
int match;
int mac_granted, match, priv_granted;
int i;
/*
@ -371,10 +371,32 @@ ugidfw_rulecheck(struct mac_bsdextended_rule *rule,
return (0);
}
/*
* MBI_APPEND should not be here as it should get converted to
* MBI_WRITE.
*/
priv_granted = 0;
mac_granted = rule->mbr_mode;
if ((acc_mode & MBI_ADMIN) && (mac_granted & MBI_ADMIN) == 0 &&
priv_check_cred(cred, PRIV_VFS_ADMIN, 0) == 0)
priv_granted |= MBI_ADMIN;
if ((acc_mode & MBI_EXEC) && (mac_granted & MBI_EXEC) == 0 &&
priv_check_cred(cred, (vap->va_type == VDIR) ? PRIV_VFS_LOOKUP :
PRIV_VFS_EXEC, 0) == 0)
priv_granted |= MBI_EXEC;
if ((acc_mode & MBI_READ) && (mac_granted & MBI_READ) == 0 &&
priv_check_cred(cred, PRIV_VFS_READ, 0) == 0)
priv_granted |= MBI_READ;
if ((acc_mode & MBI_STAT) && (mac_granted & MBI_STAT) == 0 &&
priv_check_cred(cred, PRIV_VFS_STAT, 0) == 0)
priv_granted |= MBI_STAT;
if ((acc_mode & MBI_WRITE) && (mac_granted & MBI_WRITE) == 0 &&
priv_check_cred(cred, PRIV_VFS_WRITE, 0) == 0)
priv_granted |= MBI_WRITE;
/*
* Is the access permitted?
*/
if ((rule->mbr_mode & acc_mode) != acc_mode) {
if (((mac_granted | priv_granted) & acc_mode) != acc_mode) {
if (ugidfw_logging)
log(LOG_AUTHPRIV, "mac_bsdextended: %d:%d request %d"
" on %d:%d failed. \n", cred->cr_ruid,
@ -399,12 +421,6 @@ ugidfw_check(struct ucred *cred, struct vnode *vp, struct vattr *vap,
{
int error, i;
/*
* XXXRW: More specific privilege selection needed.
*/
if (suser_cred(cred, 0) == 0)
return (0);
/*
* Since we do not separately handle append, map append to write.
*/

6
sys/sys/priv.h
View file

@ -485,12 +485,6 @@ struct thread;
struct ucred;
int priv_check(struct thread *td, int priv);
int priv_check_cred(struct ucred *cred, int priv, int flags);
/*
* Continue to support external modules that rely on suser(9) -- for now.
*/
int suser(struct thread *td);
int suser_cred(struct ucred *cred, int flags);
#endif
#endif /* !_SYS_PRIV_H_ */