HardenedBSD/sys/kern/kern_prot.c
Bruce Evans d2d3e8751c Included <sys/sysproto.h> to get central declarations for syscall args
structs and prototypes for syscalls.

Ifdefed duplicated decentralized declarations of args structs.  It's
convenient to have this visible but they are hard to maintain.  Some
are already different from the central declarations.  4.4lite2 puts
them in comments in the function headers but I wanted to avoid the
large changes for that.
1995-11-12 06:43:28 +00:00

675 lines
14 KiB
C

/*
* Copyright (c) 1982, 1986, 1989, 1990, 1991, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* 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.
*
* @(#)kern_prot.c 8.6 (Berkeley) 1/21/94
* $Id: kern_prot.c,v 1.15 1995/11/11 06:53:08 bde Exp $
*/
/*
* System calls related to processes and protection
*/
#include <sys/param.h>
#include <sys/acct.h>
#include <sys/systm.h>
#include <sys/sysproto.h>
#include <sys/ucred.h>
#include <sys/proc.h>
#include <sys/timeb.h>
#include <sys/times.h>
#include <sys/malloc.h>
#ifndef _SYS_SYSPROTO_H_
struct getpid_args {
int dummy;
};
#endif
/* ARGSUSED */
int
getpid(p, uap, retval)
struct proc *p;
struct getpid_args *uap;
int *retval;
{
*retval = p->p_pid;
#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
retval[1] = p->p_pptr->p_pid;
#endif
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct getppid_args {
int dummy;
};
#endif
/* ARGSUSED */
int
getppid(p, uap, retval)
struct proc *p;
struct getppid_args *uap;
int *retval;
{
*retval = p->p_pptr->p_pid;
return (0);
}
/* Get process group ID; note that POSIX getpgrp takes no parameter */
#ifndef _SYS_SYSPROTO_H_
struct getpgrp_args {
int dummy;
};
#endif
int
getpgrp(p, uap, retval)
struct proc *p;
struct getpgrp_args *uap;
int *retval;
{
*retval = p->p_pgrp->pg_id;
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct getuid_args {
int dummy;
};
#endif
/* ARGSUSED */
int
getuid(p, uap, retval)
struct proc *p;
struct getuid_args *uap;
int *retval;
{
*retval = p->p_cred->p_ruid;
#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
retval[1] = p->p_ucred->cr_uid;
#endif
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct geteuid_args {
int dummy;
};
#endif
/* ARGSUSED */
int
geteuid(p, uap, retval)
struct proc *p;
struct geteuid_args *uap;
int *retval;
{
*retval = p->p_ucred->cr_uid;
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct getgid_args {
int dummy;
};
#endif
/* ARGSUSED */
int
getgid(p, uap, retval)
struct proc *p;
struct getgid_args *uap;
int *retval;
{
*retval = p->p_cred->p_rgid;
#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
retval[1] = p->p_ucred->cr_groups[0];
#endif
return (0);
}
/*
* Get effective group ID. The "egid" is groups[0], and could be obtained
* via getgroups. This syscall exists because it is somewhat painful to do
* correctly in a library function.
*/
#ifndef _SYS_SYSPROTO_H_
struct getegid_args {
int dummy;
};
#endif
/* ARGSUSED */
int
getegid(p, uap, retval)
struct proc *p;
struct getegid_args *uap;
int *retval;
{
*retval = p->p_ucred->cr_groups[0];
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct getgroups_args {
u_int gidsetsize;
gid_t *gidset;
};
#endif
int
getgroups(p, uap, retval)
struct proc *p;
register struct getgroups_args *uap;
int *retval;
{
register struct pcred *pc = p->p_cred;
register u_int ngrp;
int error;
if ((ngrp = uap->gidsetsize) == 0) {
*retval = pc->pc_ucred->cr_ngroups;
return (0);
}
if (ngrp < pc->pc_ucred->cr_ngroups)
return (EINVAL);
ngrp = pc->pc_ucred->cr_ngroups;
if ((error = copyout((caddr_t)pc->pc_ucred->cr_groups,
(caddr_t)uap->gidset, ngrp * sizeof(gid_t))))
return (error);
*retval = ngrp;
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct setsid_args {
int dummy;
};
#endif
/* ARGSUSED */
int
setsid(p, uap, retval)
register struct proc *p;
struct setsid_args *uap;
int *retval;
{
if (p->p_pgid == p->p_pid || pgfind(p->p_pid)) {
return (EPERM);
} else {
(void)enterpgrp(p, p->p_pid, 1);
*retval = p->p_pid;
return (0);
}
}
/*
* set process group (setpgid/old setpgrp)
*
* caller does setpgid(targpid, targpgid)
*
* pid must be caller or child of caller (ESRCH)
* if a child
* pid must be in same session (EPERM)
* pid can't have done an exec (EACCES)
* if pgid != pid
* there must exist some pid in same session having pgid (EPERM)
* pid must not be session leader (EPERM)
*/
#ifndef _SYS_SYSPROTO_H_
struct setpgid_args {
int pid; /* target process id */
int pgid; /* target pgrp id */
};
#endif
/* ARGSUSED */
int
setpgid(curp, uap, retval)
struct proc *curp;
register struct setpgid_args *uap;
int *retval;
{
register struct proc *targp; /* target process */
register struct pgrp *pgrp; /* target pgrp */
if (uap->pid != 0 && uap->pid != curp->p_pid) {
if ((targp = pfind(uap->pid)) == 0 || !inferior(targp))
return (ESRCH);
if (targp->p_session != curp->p_session)
return (EPERM);
if (targp->p_flag & P_EXEC)
return (EACCES);
} else
targp = curp;
if (SESS_LEADER(targp))
return (EPERM);
if (uap->pgid == 0)
uap->pgid = targp->p_pid;
else if (uap->pgid != targp->p_pid)
if ((pgrp = pgfind(uap->pgid)) == 0 ||
pgrp->pg_session != curp->p_session)
return (EPERM);
return (enterpgrp(targp, uap->pgid, 0));
}
#ifndef _SYS_SYSPROTO_H_
struct setuid_args {
uid_t uid;
};
#endif
/* ARGSUSED */
int
setuid(p, uap, retval)
struct proc *p;
struct setuid_args *uap;
int *retval;
{
register struct pcred *pc = p->p_cred;
register uid_t uid;
int error;
uid = uap->uid;
if (uid != pc->p_ruid && uid != pc->p_svuid &&
(error = suser(pc->pc_ucred, &p->p_acflag)))
return (error);
/*
* Everything's okay, do it.
* Transfer proc count to new user.
* Copy credentials so other references do not see our changes.
*/
if (pc->pc_ucred->cr_uid == 0 && uid != pc->p_ruid) {
(void)chgproccnt(pc->p_ruid, -1);
(void)chgproccnt(uid, 1);
}
pc->pc_ucred = crcopy(pc->pc_ucred);
if (pc->pc_ucred->cr_uid == 0) {
pc->p_ruid = uid;
pc->p_svuid = uid;
}
pc->pc_ucred->cr_uid = uid;
p->p_flag |= P_SUGID;
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct seteuid_args {
uid_t euid;
};
#endif
/* ARGSUSED */
int
seteuid(p, uap, retval)
struct proc *p;
struct seteuid_args *uap;
int *retval;
{
register struct pcred *pc = p->p_cred;
register uid_t euid;
int error;
euid = uap->euid;
if (euid != pc->p_ruid && euid != pc->p_svuid &&
(error = suser(pc->pc_ucred, &p->p_acflag)))
return (error);
/*
* Everything's okay, do it. Copy credentials so other references do
* not see our changes.
*/
pc->pc_ucred = crcopy(pc->pc_ucred);
pc->pc_ucred->cr_uid = euid;
p->p_flag |= P_SUGID;
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct setgid_args {
gid_t gid;
};
#endif
/* ARGSUSED */
int
setgid(p, uap, retval)
struct proc *p;
struct setgid_args *uap;
int *retval;
{
register struct pcred *pc = p->p_cred;
register gid_t gid;
int error;
gid = uap->gid;
if (gid != pc->p_rgid && gid != pc->p_svgid &&
(error = suser(pc->pc_ucred, &p->p_acflag)))
return (error);
pc->pc_ucred = crcopy(pc->pc_ucred);
pc->pc_ucred->cr_groups[0] = gid;
if (pc->pc_ucred->cr_uid == 0) {
pc->p_rgid = gid;
pc->p_svgid = gid;
}
p->p_flag |= P_SUGID;
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct setegid_args {
gid_t egid;
};
#endif
/* ARGSUSED */
int
setegid(p, uap, retval)
struct proc *p;
struct setegid_args *uap;
int *retval;
{
register struct pcred *pc = p->p_cred;
register gid_t egid;
int error;
egid = uap->egid;
if (egid != pc->p_rgid && egid != pc->p_svgid &&
(error = suser(pc->pc_ucred, &p->p_acflag)))
return (error);
pc->pc_ucred = crcopy(pc->pc_ucred);
pc->pc_ucred->cr_groups[0] = egid;
p->p_flag |= P_SUGID;
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct setgroups_args {
u_int gidsetsize;
gid_t *gidset;
};
#endif
/* ARGSUSED */
int
setgroups(p, uap, retval)
struct proc *p;
struct setgroups_args *uap;
int *retval;
{
register struct pcred *pc = p->p_cred;
register u_int ngrp;
int error;
if ((error = suser(pc->pc_ucred, &p->p_acflag)))
return (error);
ngrp = uap->gidsetsize;
if (ngrp < 1 || ngrp > NGROUPS)
return (EINVAL);
pc->pc_ucred = crcopy(pc->pc_ucred);
if ((error = copyin((caddr_t)uap->gidset,
(caddr_t)pc->pc_ucred->cr_groups, ngrp * sizeof(gid_t))))
return (error);
pc->pc_ucred->cr_ngroups = ngrp;
p->p_flag |= P_SUGID;
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct setreuid_args {
uid_t ruid;
uid_t euid;
};
#endif
/* ARGSUSED */
int
setreuid(p, uap, retval)
register struct proc *p;
struct setreuid_args *uap;
int *retval;
{
register struct pcred *pc = p->p_cred;
register uid_t ruid, euid;
int error;
ruid = uap->ruid;
euid = uap->euid;
if ((ruid != (uid_t)-1 && ruid != pc->p_ruid && ruid != pc->p_svuid ||
euid != (uid_t)-1 && euid != pc->p_ruid && euid != pc->p_svuid) &&
(error = suser(pc->pc_ucred, &p->p_acflag)))
return (error);
pc->pc_ucred = crcopy(pc->pc_ucred);
if (euid != (uid_t)-1)
pc->pc_ucred->cr_uid = euid;
if (ruid != (uid_t)-1 && ruid != pc->p_ruid) {
(void)chgproccnt(pc->p_ruid, -1);
(void)chgproccnt(ruid, 1);
pc->p_ruid = ruid;
}
if (ruid != (uid_t)-1 || pc->pc_ucred->cr_uid != pc->p_ruid)
pc->p_svuid = pc->pc_ucred->cr_uid;
p->p_flag |= P_SUGID;
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct setregid_args {
gid_t rgid;
gid_t egid;
};
#endif
/* ARGSUSED */
int
setregid(p, uap, retval)
register struct proc *p;
struct setregid_args *uap;
int *retval;
{
register struct pcred *pc = p->p_cred;
register gid_t rgid, egid;
int error;
rgid = uap->rgid;
egid = uap->egid;
if ((rgid != (gid_t)-1 && rgid != pc->p_rgid && rgid != pc->p_svgid ||
egid != (gid_t)-1 && egid != pc->p_rgid && egid != pc->p_svgid) &&
(error = suser(pc->pc_ucred, &p->p_acflag)))
return (error);
pc->pc_ucred = crcopy(pc->pc_ucred);
if (egid != (gid_t)-1)
pc->pc_ucred->cr_groups[0] = egid;
if (rgid != (gid_t)-1)
pc->p_rgid = rgid;
if (rgid != (gid_t)-1 || pc->pc_ucred->cr_groups[0] != pc->p_rgid)
pc->p_svgid = pc->pc_ucred->cr_groups[0];
p->p_flag |= P_SUGID;
return (0);
}
/*
* Check if gid is a member of the group set.
*/
int
groupmember(gid, cred)
gid_t gid;
register struct ucred *cred;
{
register gid_t *gp;
gid_t *egp;
egp = &(cred->cr_groups[cred->cr_ngroups]);
for (gp = cred->cr_groups; gp < egp; gp++)
if (*gp == gid)
return (1);
return (0);
}
/*
* Test whether the specified credentials imply "super-user"
* privilege; if so, and we have accounting info, set the flag
* indicating use of super-powers.
* Returns 0 or error.
*/
int
suser(cred, acflag)
struct ucred *cred;
u_short *acflag;
{
if (cred->cr_uid == 0) {
if (acflag)
*acflag |= ASU;
return (0);
}
return (EPERM);
}
/*
* Allocate a zeroed cred structure.
*/
struct ucred *
crget()
{
register struct ucred *cr;
MALLOC(cr, struct ucred *, sizeof(*cr), M_CRED, M_WAITOK);
bzero((caddr_t)cr, sizeof(*cr));
cr->cr_ref = 1;
return (cr);
}
/*
* Free a cred structure.
* Throws away space when ref count gets to 0.
*/
void
crfree(cr)
struct ucred *cr;
{
int s;
s = splimp(); /* ??? */
if (--cr->cr_ref == 0)
FREE((caddr_t)cr, M_CRED);
(void) splx(s);
}
/*
* Copy cred structure to a new one and free the old one.
*/
struct ucred *
crcopy(cr)
struct ucred *cr;
{
struct ucred *newcr;
if (cr->cr_ref == 1)
return (cr);
newcr = crget();
*newcr = *cr;
crfree(cr);
newcr->cr_ref = 1;
return (newcr);
}
/*
* Dup cred struct to a new held one.
*/
struct ucred *
crdup(cr)
struct ucred *cr;
{
struct ucred *newcr;
newcr = crget();
*newcr = *cr;
newcr->cr_ref = 1;
return (newcr);
}
/*
* Get login name, if available.
*/
#ifndef _SYS_SYSPROTO_H_
struct getlogin_args {
char *namebuf;
u_int namelen;
};
#endif
/* ARGSUSED */
int
getlogin(p, uap, retval)
struct proc *p;
struct getlogin_args *uap;
int *retval;
{
if (uap->namelen > sizeof (p->p_pgrp->pg_session->s_login))
uap->namelen = sizeof (p->p_pgrp->pg_session->s_login);
return (copyout((caddr_t) p->p_pgrp->pg_session->s_login,
(caddr_t) uap->namebuf, uap->namelen));
}
/*
* Set login name.
*/
#ifndef _SYS_SYSPROTO_H_
struct setlogin_args {
char *namebuf;
};
#endif
/* ARGSUSED */
int
setlogin(p, uap, retval)
struct proc *p;
struct setlogin_args *uap;
int *retval;
{
int error;
if ((error = suser(p->p_ucred, &p->p_acflag)))
return (error);
error = copyinstr((caddr_t) uap->namebuf,
(caddr_t) p->p_pgrp->pg_session->s_login,
sizeof (p->p_pgrp->pg_session->s_login) - 1, (u_int *)0);
if (error == ENAMETOOLONG)
error = EINVAL;
return (error);
}