[unix-history] / sys / kern / kern_prot.c

/*
 * 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.
 *
 *	from: @(#)kern_prot.c	7.21 (Berkeley) 5/3/91
 *	$Id: kern_prot.c,v 1.5 1993/12/19 00:51:29 wollman Exp $
 */

/*
 * System calls related to processes and protection
 */

#include "param.h"
#include "systm.h"
#include "acct.h"
#include "ucred.h"
#include "proc.h"
#include "timeb.h"
#include "times.h"
#include "malloc.h"

/* ARGSUSED */
int
getpid(p, uap, retval)
	struct proc *p;
	void *uap;
	int *retval;
{

	*retval = p->p_pid;
#ifdef COMPAT_43
	retval[1] = p->p_pptr->p_pid;
#endif
	return (0);
}

/* ARGSUSED */
int
getppid(p, uap, retval)
	struct proc *p;
	void *uap;
	int *retval;
{

	*retval = p->p_pptr->p_pid;
	return (0);
}

/* Get process group ID; note that POSIX getpgrp takes no parameter */
int
getpgrp(p, uap, retval)
	struct proc *p;
	void *uap;
	int *retval;
{

	*retval = p->p_pgrp->pg_id;
	return (0);
}

/* ARGSUSED */
int
getuid(p, uap, retval)
	struct proc *p;
	void *uap;
	int *retval;
{

	*retval = p->p_cred->p_ruid;
#ifdef COMPAT_43
	retval[1] = p->p_ucred->cr_uid;
#endif
	return (0);
}

/* ARGSUSED */
int
geteuid(p, uap, retval)
	struct proc *p;
	void *uap;
	int *retval;
{

	*retval = p->p_ucred->cr_uid;
	return (0);
}

/* ARGSUSED */
int
getgid(p, uap, retval)
	struct proc *p;
	void *uap;
	int *retval;
{

	*retval = p->p_cred->p_rgid;
#ifdef COMPAT_43
	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.
 */
/* ARGSUSED */
int
getegid(p, uap, retval)
	struct proc *p;
	void *uap;
	int *retval;
{

	*retval = p->p_ucred->cr_groups[0];
	return (0);
}

struct getgroups_args {
	u_int	gidsetsize;
	int	*gidset;		/* XXX not yet POSIX */
};

int
getgroups(p, uap, retval)
	struct proc *p;
	register struct getgroups_args *uap;
	int *retval;
{
	register struct pcred *pc = p->p_cred;
	register gid_t *gp;
	register int *lp;
	register u_int ngrp;
	int groups[NGROUPS];
	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;
	for (gp = pc->pc_ucred->cr_groups, lp = groups; lp < &groups[ngrp]; )
		*lp++ = *gp++;
	if (error = copyout((caddr_t)groups, (caddr_t)uap->gidset,
	    ngrp * sizeof (groups[0])))
		return (error);
	*retval = ngrp;
	return (0);
}

/* ARGSUSED */
int
setsid(p, uap, retval)
	register struct proc *p;
	void *uap;
	int *retval;
{

	if (p->p_pgid == p->p_pid || pgfind(p->p_pid)) {
		return (EPERM);
	} else {
		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)
 */

struct setpgid_args {
	int	pid;	/* target process id */
	int	pgid;	/* target pgrp id */
};

/* 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&SEXEC)
			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);
	enterpgrp(targp, uap->pgid, 0);
	return (0);
}

struct setuid_args {
	int	uid;
};

/* 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 &&
	    (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 = uid;
	pc->p_ruid = uid;
	pc->p_svuid = uid;
	p->p_flag |= SUGID;
	return (0);
}

struct seteuid_args {
	int	euid;
};

/* 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 |= SUGID;
	return (0);
}

struct setgid_args {
	int	gid;
};

/* 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 && (error = suser(pc->pc_ucred, &p->p_acflag)))
		return (error);
	pc->pc_ucred = crcopy(pc->pc_ucred);
	pc->pc_ucred->cr_groups[0] = gid;
	pc->p_rgid = gid;
	pc->p_svgid = gid;
	p->p_flag |= SUGID;
	return (0);
}

struct setegid_args {
	int	egid;
};

/* 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 |= SUGID;
	return (0);
}

#ifdef COMPAT_43

struct osetreuid_args {
	int	ruid;
	int	euid;
};

/* ARGSUSED */
int
osetreuid(p, uap, retval)
	register struct proc *p;
	struct osetreuid_args *uap;
	int *retval;
{
	register struct pcred *pc = p->p_cred;
	struct seteuid_args e_args;

	/*
	 * Most calls to setreuid() are done in order to swap real and
	 * effective uids.  In old versions of BSD, this was the only
	 * way to temporarily renounce privileges and be able to get
	 * them back.  In the presence of the POSIX saved id, however,
	 * we can do this without modifying the real uid, which could have
	 * opened up a security hole.  So, we implement this: when the user
	 * attempts to set its real uid, we just check to make sure
	 * that they will be able to seteuid() back to that id at some
	 * later time, but don't actually change the real uid.
	 * Logic taken from 4.4BSD.
	 */
	if(uap->ruid != -1 && uap->ruid != pc->p_ruid
	   && uap->ruid != pc->p_svuid) {
		return EPERM;
	}

	if(uap->euid == -1) {
		return 0;
	}
	e_args.euid = uap->euid;
	return seteuid(p, &e_args, retval);
}

struct osetregid_args {
	int	rgid;
	int	egid;
};

/* ARGSUSED */
int
osetregid(p, uap, retval)
	register struct proc *p;
	struct osetregid_args *uap;
	int *retval;
{
	register struct pcred *pc = p->p_cred;
	struct setegid_args e_args;

	/*
	 * Same comments as for setreuid() apply here.
	 */
	if(uap->rgid != -1
	   && uap->rgid != pc->p_rgid
	   && uap->rgid != pc->p_svgid) {
		return EPERM;
	}

	if(uap->egid == -1) {
		return 0;
	}
	e_args.egid = uap->egid;
	return setegid(p, &e_args, retval);
}
#endif

struct setgroups_args {
	u_int	gidsetsize;
	int	*gidset;
};

/* ARGSUSED */
int
setgroups(p, uap, retval)
	struct proc *p;
	struct setgroups_args *uap;
	int *retval;
{
	register struct pcred *pc = p->p_cred;
	register gid_t *gp;
	register u_int ngrp;
	register int *lp;
	int error, groups[NGROUPS];

	if (error = suser(pc->pc_ucred, &p->p_acflag))
		return (error);
	if ((ngrp = uap->gidsetsize) > NGROUPS)
		return (EINVAL);
	if (error = copyin((caddr_t)uap->gidset, (caddr_t)groups,
	    ngrp * sizeof (groups[0])))
		return (error);
	pc->pc_ucred = crcopy(pc->pc_ucred);
	pc->pc_ucred->cr_ngroups = ngrp;
	/* convert from int's to gid_t's */
	for (gp = pc->pc_ucred->cr_groups, lp = groups; ngrp--; )
		*gp++ = *lp++;
	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 = splimp();			/* ??? XXX FIXME */

	if (--cr->cr_ref != 0) {
		(void) splx(s);
		return;
	}
	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.
 */

struct getlogin_args {
	char	*namebuf;
	u_int	namelen;
};

/* 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.
 */

struct setlogin_args {
	char	*namebuf;
};

/* 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);
}
Commit	Line	Data
15637ed4 RG	1	/*
	2	* Copyright (c) 1982, 1986, 1989, 1990, 1991 Regents of the University
	3	* of California. All rights reserved.
	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions
	7	* are met:
	8	* 1. Redistributions of source code must retain the above copyright
	9	* notice, this list of conditions and the following disclaimer.
	10	* 2. Redistributions in binary form must reproduce the above copyright
	11	* notice, this list of conditions and the following disclaimer in the
	12	* documentation and/or other materials provided with the distribution.
	13	* 3. All advertising materials mentioning features or use of this software
	14	* must display the following acknowledgement:
	15	* This product includes software developed by the University of
	16	* California, Berkeley and its contributors.
	17	* 4. Neither the name of the University nor the names of its contributors
	18	* may be used to endorse or promote products derived from this software
	19	* without specific prior written permission.
	20	*
	21	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	22	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	23	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	24	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	25	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	26	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	27	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	28	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	29	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	30	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	31	* SUCH DAMAGE.
	32	*
600f7f07	33	* from: @(#)kern_prot.c 7.21 (Berkeley) 5/3/91
67c9e20b	34	* $Id: kern_prot.c,v 1.5 1993/12/19 00:51:29 wollman Exp $
15637ed4 RG	35	*/
	36
	37	/*
	38	* System calls related to processes and protection
	39	*/
	40
	41	#include "param.h"
15637ed4	42	#include "systm.h"
fde1aeb2	43	#include "acct.h"
15637ed4 RG	44	#include "ucred.h"
	45	#include "proc.h"
	46	#include "timeb.h"
	47	#include "times.h"
	48	#include "malloc.h"
	49
	50	/* ARGSUSED */
4c45483e	51	int
15637ed4 RG	52	getpid(p, uap, retval)
	53	struct proc *p;
	54	void *uap;
	55	int *retval;
	56	{
	57
	58	*retval = p->p_pid;
	59	#ifdef COMPAT_43
	60	retval[1] = p->p_pptr->p_pid;
	61	#endif
	62	return (0);
	63	}
	64
	65	/* ARGSUSED */
4c45483e	66	int
15637ed4 RG	67	getppid(p, uap, retval)
	68	struct proc *p;
	69	void *uap;
	70	int *retval;
	71	{
	72
	73	*retval = p->p_pptr->p_pid;
	74	return (0);
	75	}
	76
	77	/* Get process group ID; note that POSIX getpgrp takes no parameter */
4c45483e	78	int
15637ed4 RG	79	getpgrp(p, uap, retval)
	80	struct proc *p;
	81	void *uap;
	82	int *retval;
	83	{
	84
	85	*retval = p->p_pgrp->pg_id;
	86	return (0);
	87	}
	88
	89	/* ARGSUSED */
4c45483e	90	int
15637ed4 RG	91	getuid(p, uap, retval)
	92	struct proc *p;
	93	void *uap;
	94	int *retval;
	95	{
	96
	97	*retval = p->p_cred->p_ruid;
	98	#ifdef COMPAT_43
	99	retval[1] = p->p_ucred->cr_uid;
	100	#endif
	101	return (0);
	102	}
	103
	104	/* ARGSUSED */
4c45483e	105	int
15637ed4 RG	106	geteuid(p, uap, retval)
	107	struct proc *p;
	108	void *uap;
	109	int *retval;
	110	{
	111
	112	*retval = p->p_ucred->cr_uid;
	113	return (0);
	114	}
	115
	116	/* ARGSUSED */
4c45483e	117	int
15637ed4 RG	118	getgid(p, uap, retval)
	119	struct proc *p;
	120	void *uap;
	121	int *retval;
	122	{
	123
	124	*retval = p->p_cred->p_rgid;
	125	#ifdef COMPAT_43
	126	retval[1] = p->p_ucred->cr_groups[0];
	127	#endif
	128	return (0);
	129	}
	130
	131	/*
	132	* Get effective group ID. The "egid" is groups[0], and could be obtained
	133	* via getgroups. This syscall exists because it is somewhat painful to do
	134	* correctly in a library function.
	135	*/
	136	/* ARGSUSED */
4c45483e	137	int
15637ed4 RG	138	getegid(p, uap, retval)
	139	struct proc *p;
	140	void *uap;
	141	int *retval;
	142	{
	143
	144	*retval = p->p_ucred->cr_groups[0];
	145	return (0);
	146	}
	147
3c7eb27c DG	148	struct getgroups_args {
	149	u_int gidsetsize;
	150	int gidset; / XXX not yet POSIX */
	151	};
	152
4c45483e	153	int
15637ed4 RG	154	getgroups(p, uap, retval)
15637ed4 RG	155	struct proc *p;
3c7eb27c	156	register struct getgroups_args *uap;
15637ed4 RG	157	int *retval;
	158	{
	159	register struct pcred *pc = p->p_cred;
	160	register gid_t *gp;
	161	register int *lp;
	162	register u_int ngrp;
	163	int groups[NGROUPS];
	164	int error;
	165
	166	if ((ngrp = uap->gidsetsize) == 0) {
	167	*retval = pc->pc_ucred->cr_ngroups;
	168	return (0);
	169	}
	170	if (ngrp < pc->pc_ucred->cr_ngroups)
	171	return (EINVAL);
	172	ngrp = pc->pc_ucred->cr_ngroups;
	173	for (gp = pc->pc_ucred->cr_groups, lp = groups; lp < &groups[ngrp]; )
	174	lp++ = gp++;
	175	if (error = copyout((caddr_t)groups, (caddr_t)uap->gidset,
	176	ngrp * sizeof (groups[0])))
	177	return (error);
	178	*retval = ngrp;
	179	return (0);
	180	}
	181
	182	/* ARGSUSED */
4c45483e	183	int
15637ed4 RG	184	setsid(p, uap, retval)
	185	register struct proc *p;
	186	void *uap;
	187	int *retval;
	188	{
	189
	190	if (p->p_pgid == p->p_pid \|\| pgfind(p->p_pid)) {
	191	return (EPERM);
	192	} else {
	193	enterpgrp(p, p->p_pid, 1);
	194	*retval = p->p_pid;
	195	return (0);
	196	}
	197	}
	198
	199	/*
	200	* set process group (setpgid/old setpgrp)
	201	*
	202	* caller does setpgid(targpid, targpgid)
	203	*
	204	* pid must be caller or child of caller (ESRCH)
	205	* if a child
	206	* pid must be in same session (EPERM)
	207	* pid can't have done an exec (EACCES)
	208	* if pgid != pid
	209	* there must exist some pid in same session having pgid (EPERM)
	210	* pid must not be session leader (EPERM)
	211	*/
3c7eb27c DG	212
	213	struct setpgid_args {
	214	int pid; /* target process id */
	215	int pgid; /* target pgrp id */
	216	};
	217
15637ed4	218	/* ARGSUSED */
4c45483e	219	int
15637ed4 RG	220	setpgid(curp, uap, retval)
15637ed4 RG	221	struct proc *curp;
3c7eb27c	222	register struct setpgid_args *uap;
15637ed4 RG	223	int *retval;
	224	{
	225	register struct proc targp; / target process */
	226	register struct pgrp pgrp; / target pgrp */
	227
	228	if (uap->pid != 0 && uap->pid != curp->p_pid) {
	229	if ((targp = pfind(uap->pid)) == 0 \|\| !inferior(targp))
	230	return (ESRCH);
	231	if (targp->p_session != curp->p_session)
	232	return (EPERM);
	233	if (targp->p_flag&SEXEC)
	234	return (EACCES);
	235	} else
	236	targp = curp;
	237	if (SESS_LEADER(targp))
	238	return (EPERM);
	239	if (uap->pgid == 0)
	240	uap->pgid = targp->p_pid;
	241	else if (uap->pgid != targp->p_pid)
	242	if ((pgrp = pgfind(uap->pgid)) == 0 \|\|
	243	pgrp->pg_session != curp->p_session)
	244	return (EPERM);
	245	enterpgrp(targp, uap->pgid, 0);
	246	return (0);
	247	}
	248
3c7eb27c DG	249	struct setuid_args {
	250	int uid;
	251	};
	252
15637ed4	253	/* ARGSUSED */
4c45483e	254	int
15637ed4 RG	255	setuid(p, uap, retval)
15637ed4 RG	256	struct proc *p;
3c7eb27c	257	struct setuid_args *uap;
15637ed4 RG	258	int *retval;
	259	{
	260	register struct pcred *pc = p->p_cred;
	261	register uid_t uid;
	262	int error;
	263
	264	uid = uap->uid;
	265	if (uid != pc->p_ruid &&
	266	(error = suser(pc->pc_ucred, &p->p_acflag)))
	267	return (error);
	268	/*
	269	* Everything's okay, do it. Copy credentials so other references do
	270	* not see our changes.
	271	*/
	272	pc->pc_ucred = crcopy(pc->pc_ucred);
	273	pc->pc_ucred->cr_uid = uid;
	274	pc->p_ruid = uid;
	275	pc->p_svuid = uid;
67c9e20b	276	p->p_flag \|= SUGID;
15637ed4 RG	277	return (0);
	278	}
	279
3c7eb27c DG	280	struct seteuid_args {
	281	int euid;
	282	};
	283
15637ed4	284	/* ARGSUSED */
4c45483e	285	int
15637ed4 RG	286	seteuid(p, uap, retval)
15637ed4 RG	287	struct proc *p;
3c7eb27c	288	struct seteuid_args *uap;
15637ed4 RG	289	int *retval;
	290	{
	291	register struct pcred *pc = p->p_cred;
	292	register uid_t euid;
	293	int error;
	294
	295	euid = uap->euid;
	296	if (euid != pc->p_ruid && euid != pc->p_svuid &&
	297	(error = suser(pc->pc_ucred, &p->p_acflag)))
	298	return (error);
	299	/*
	300	* Everything's okay, do it. Copy credentials so other references do
	301	* not see our changes.
	302	*/
	303	pc->pc_ucred = crcopy(pc->pc_ucred);
	304	pc->pc_ucred->cr_uid = euid;
67c9e20b	305	p->p_flag \|= SUGID;
15637ed4 RG	306	return (0);
	307	}
	308
3c7eb27c DG	309	struct setgid_args {
	310	int gid;
	311	};
	312
15637ed4	313	/* ARGSUSED */
4c45483e	314	int
15637ed4 RG	315	setgid(p, uap, retval)
15637ed4 RG	316	struct proc *p;
3c7eb27c	317	struct setgid_args *uap;
15637ed4 RG	318	int *retval;
	319	{
	320	register struct pcred *pc = p->p_cred;
	321	register gid_t gid;
	322	int error;
	323
	324	gid = uap->gid;
	325	if (gid != pc->p_rgid && (error = suser(pc->pc_ucred, &p->p_acflag)))
	326	return (error);
	327	pc->pc_ucred = crcopy(pc->pc_ucred);
	328	pc->pc_ucred->cr_groups[0] = gid;
	329	pc->p_rgid = gid;
67c9e20b GW	330	pc->p_svgid = gid;
67c9e20b GW	331	p->p_flag \|= SUGID;
15637ed4 RG	332	return (0);
	333	}
	334
3c7eb27c DG	335	struct setegid_args {
	336	int egid;
	337	};
	338
15637ed4	339	/* ARGSUSED */
4c45483e	340	int
15637ed4 RG	341	setegid(p, uap, retval)
15637ed4 RG	342	struct proc *p;
3c7eb27c	343	struct setegid_args *uap;
15637ed4 RG	344	int *retval;
	345	{
	346	register struct pcred *pc = p->p_cred;
	347	register gid_t egid;
	348	int error;
	349
	350	egid = uap->egid;
	351	if (egid != pc->p_rgid && egid != pc->p_svgid &&
	352	(error = suser(pc->pc_ucred, &p->p_acflag)))
	353	return (error);
	354	pc->pc_ucred = crcopy(pc->pc_ucred);
	355	pc->pc_ucred->cr_groups[0] = egid;
67c9e20b	356	p->p_flag \|= SUGID;
15637ed4 RG	357	return (0);
	358	}
	359
	360	#ifdef COMPAT_43
3c7eb27c DG	361
	362	struct osetreuid_args {
	363	int ruid;
	364	int euid;
	365	};
	366
15637ed4	367	/* ARGSUSED */
4c45483e	368	int
15637ed4 RG	369	osetreuid(p, uap, retval)
15637ed4 RG	370	register struct proc *p;
3c7eb27c	371	struct osetreuid_args *uap;
15637ed4 RG	372	int *retval;
	373	{
	374	register struct pcred *pc = p->p_cred;
67c9e20b	375	struct seteuid_args e_args;
15637ed4	376
15637ed4	377	/*
67c9e20b GW	378	* Most calls to setreuid() are done in order to swap real and
	379	* effective uids. In old versions of BSD, this was the only
	380	* way to temporarily renounce privileges and be able to get
	381	* them back. In the presence of the POSIX saved id, however,
	382	* we can do this without modifying the real uid, which could have
	383	* opened up a security hole. So, we implement this: when the user
	384	* attempts to set its real uid, we just check to make sure
	385	* that they will be able to seteuid() back to that id at some
	386	* later time, but don't actually change the real uid.
	387	* Logic taken from 4.4BSD.
15637ed4	388	*/
67c9e20b GW	389	if(uap->ruid != -1 && uap->ruid != pc->p_ruid
	390	&& uap->ruid != pc->p_svuid) {
	391	return EPERM;
	392	}
	393
	394	if(uap->euid == -1) {
	395	return 0;
	396	}
	397	e_args.euid = uap->euid;
	398	return seteuid(p, &e_args, retval);
15637ed4 RG	399	}
15637ed4 RG	400
3c7eb27c DG	401	struct osetregid_args {
	402	int rgid;
	403	int egid;
	404	};
	405
15637ed4	406	/* ARGSUSED */
4c45483e	407	int
15637ed4 RG	408	osetregid(p, uap, retval)
15637ed4 RG	409	register struct proc *p;
3c7eb27c	410	struct osetregid_args *uap;
15637ed4 RG	411	int *retval;
	412	{
	413	register struct pcred *pc = p->p_cred;
67c9e20b	414	struct setegid_args e_args;
15637ed4	415
15637ed4	416	/*
67c9e20b	417	* Same comments as for setreuid() apply here.
15637ed4	418	*/
67c9e20b GW	419	if(uap->rgid != -1
	420	&& uap->rgid != pc->p_rgid
	421	&& uap->rgid != pc->p_svgid) {
	422	return EPERM;
	423	}
	424
	425	if(uap->egid == -1) {
	426	return 0;
	427	}
	428	e_args.egid = uap->egid;
	429	return setegid(p, &e_args, retval);
15637ed4 RG	430	}
	431	#endif
	432
3c7eb27c DG	433	struct setgroups_args {
	434	u_int gidsetsize;
	435	int *gidset;
	436	};
	437
15637ed4	438	/* ARGSUSED */
4c45483e	439	int
15637ed4 RG	440	setgroups(p, uap, retval)
15637ed4 RG	441	struct proc *p;
3c7eb27c	442	struct setgroups_args *uap;
15637ed4 RG	443	int *retval;
	444	{
	445	register struct pcred *pc = p->p_cred;
	446	register gid_t *gp;
	447	register u_int ngrp;
	448	register int *lp;
	449	int error, groups[NGROUPS];
	450
	451	if (error = suser(pc->pc_ucred, &p->p_acflag))
	452	return (error);
	453	if ((ngrp = uap->gidsetsize) > NGROUPS)
	454	return (EINVAL);
	455	if (error = copyin((caddr_t)uap->gidset, (caddr_t)groups,
	456	ngrp * sizeof (groups[0])))
	457	return (error);
	458	pc->pc_ucred = crcopy(pc->pc_ucred);
	459	pc->pc_ucred->cr_ngroups = ngrp;
	460	/* convert from int's to gid_t's */
	461	for (gp = pc->pc_ucred->cr_groups, lp = groups; ngrp--; )
	462	gp++ = lp++;
	463	return (0);
	464	}
	465
	466	/*
	467	* Check if gid is a member of the group set.
	468	*/
4c45483e	469	int
15637ed4 RG	470	groupmember(gid, cred)
	471	gid_t gid;
	472	register struct ucred *cred;
	473	{
	474	register gid_t *gp;
	475	gid_t *egp;
	476
	477	egp = &(cred->cr_groups[cred->cr_ngroups]);
	478	for (gp = cred->cr_groups; gp < egp; gp++)
	479	if (*gp == gid)
	480	return (1);
	481	return (0);
	482	}
	483
	484	/*
	485	* Test whether the specified credentials imply "super-user"
	486	* privilege; if so, and we have accounting info, set the flag
	487	* indicating use of super-powers.
	488	* Returns 0 or error.
	489	*/
4c45483e	490	int
15637ed4 RG	491	suser(cred, acflag)
	492	struct ucred *cred;
	493	u_short *acflag;
	494	{
	495	if (cred->cr_uid == 0) {
	496	if (acflag)
	497	*acflag \|= ASU;
	498	return (0);
	499	}
	500	return (EPERM);
	501	}
	502
	503	/*
	504	* Allocate a zeroed cred structure.
	505	*/
	506	struct ucred *
	507	crget()
	508	{
	509	register struct ucred *cr;
	510
	511	MALLOC(cr, struct ucred , sizeof(cr), M_CRED, M_WAITOK);
	512	bzero((caddr_t)cr, sizeof(*cr));
	513	cr->cr_ref = 1;
	514	return (cr);
	515	}
	516
	517	/*
	518	* Free a cred structure.
	519	* Throws away space when ref count gets to 0.
	520	*/
4c45483e	521	void
15637ed4 RG	522	crfree(cr)
	523	struct ucred *cr;
	524	{
4c45483e	525	int s = splimp(); /* ??? XXX FIXME */
15637ed4 RG	526
	527	if (--cr->cr_ref != 0) {
	528	(void) splx(s);
	529	return;
	530	}
	531	FREE((caddr_t)cr, M_CRED);
	532	(void) splx(s);
	533	}
	534
	535	/*
	536	* Copy cred structure to a new one and free the old one.
	537	*/
	538	struct ucred *
	539	crcopy(cr)
	540	struct ucred *cr;
	541	{
	542	struct ucred *newcr;
	543
	544	if (cr->cr_ref == 1)
	545	return (cr);
	546	newcr = crget();
	547	newcr = cr;
	548	crfree(cr);
	549	newcr->cr_ref = 1;
	550	return (newcr);
	551	}
	552
	553	/*
	554	* Dup cred struct to a new held one.
	555	*/
	556	struct ucred *
	557	crdup(cr)
	558	struct ucred *cr;
	559	{
	560	struct ucred *newcr;
	561
	562	newcr = crget();
	563	newcr = cr;
	564	newcr->cr_ref = 1;
	565	return (newcr);
	566	}
	567
	568	/*
	569	* Get login name, if available.
	570	*/
3c7eb27c DG	571
	572	struct getlogin_args {
	573	char *namebuf;
	574	u_int namelen;
	575	};
	576
15637ed4	577	/* ARGSUSED */
4c45483e	578	int
15637ed4 RG	579	getlogin(p, uap, retval)
15637ed4 RG	580	struct proc *p;
3c7eb27c	581	struct getlogin_args *uap;
15637ed4 RG	582	int *retval;
	583	{
	584
	585	if (uap->namelen > sizeof (p->p_pgrp->pg_session->s_login))
	586	uap->namelen = sizeof (p->p_pgrp->pg_session->s_login);
	587	return (copyout((caddr_t) p->p_pgrp->pg_session->s_login,
	588	(caddr_t) uap->namebuf, uap->namelen));
	589	}
	590
	591	/*
	592	* Set login name.
	593	*/
3c7eb27c DG	594
	595	struct setlogin_args {
	596	char *namebuf;
	597	};
	598
15637ed4	599	/* ARGSUSED */
4c45483e	600	int
15637ed4 RG	601	setlogin(p, uap, retval)
15637ed4 RG	602	struct proc *p;
3c7eb27c	603	struct setlogin_args *uap;
15637ed4 RG	604	int *retval;
	605	{
	606	int error;
	607
	608	if (error = suser(p->p_ucred, &p->p_acflag))
	609	return (error);
	610	error = copyinstr((caddr_t) uap->namebuf,
	611	(caddr_t) p->p_pgrp->pg_session->s_login,
	612	sizeof (p->p_pgrp->pg_session->s_login) - 1, (u_int *)0);
	613	if (error == ENAMETOOLONG)
	614	error = EINVAL;
	615	return (error);
	616	}