505 lines
12 KiB
C
505 lines
12 KiB
C
/* $NetBSD: setmode.c,v 1.7 2004/03/12 15:21:13 grant Exp $ */
|
|
|
|
/*
|
|
* Copyright (c) 1989, 1993, 1994
|
|
* The Regents of the University of California. All rights reserved.
|
|
*
|
|
* This code is derived from software contributed to Berkeley by
|
|
* Dave Borman at Cray Research, 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. 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 HAVE_CONFIG_H
|
|
#include "nbcompat/nbconfig.h"
|
|
#endif
|
|
|
|
#if HAVE_SYS_CDEFS_H
|
|
#include <sys/cdefs.h>
|
|
#endif
|
|
|
|
#if defined(LIBC_SCCS) && !defined(lint)
|
|
#if 0
|
|
static char sccsid[] = "@(#)setmode.c 8.2 (Berkeley) 3/25/94";
|
|
#else
|
|
__RCSID("$NetBSD: setmode.c,v 1.7 2004/03/12 15:21:13 grant Exp $");
|
|
#endif
|
|
#endif /* LIBC_SCCS and not lint */
|
|
|
|
#include "namespace.h"
|
|
#include <sys/types.h>
|
|
#include <sys/stat.h>
|
|
|
|
#include <assert.h>
|
|
#include <ctype.h>
|
|
#include <errno.h>
|
|
#include <signal.h>
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
|
|
#ifdef SETMODE_DEBUG
|
|
#include <stdio.h>
|
|
#endif
|
|
|
|
#ifndef S_ISTXT
|
|
#define S_ISTXT S_ISVTX
|
|
#endif
|
|
|
|
#ifndef _DIAGASSERT
|
|
#define _DIAGASSERT(cond) assert(cond)
|
|
#endif
|
|
|
|
#if 0
|
|
#ifndef __ELF__
|
|
#define _getmode getmode
|
|
#define _setmode setmode
|
|
#else
|
|
#ifdef __weak_alias
|
|
__weak_alias(getmode,_getmode)
|
|
__weak_alias(setmode,_setmode)
|
|
#endif
|
|
#endif
|
|
#endif
|
|
|
|
#define SET_LEN 6 /* initial # of bitcmd struct to malloc */
|
|
#define SET_LEN_INCR 4 /* # of bitcmd structs to add as needed */
|
|
|
|
typedef struct bitcmd {
|
|
char cmd;
|
|
char cmd2;
|
|
mode_t bits;
|
|
} BITCMD;
|
|
|
|
#define CMD2_CLR 0x01
|
|
#define CMD2_SET 0x02
|
|
#define CMD2_GBITS 0x04
|
|
#define CMD2_OBITS 0x08
|
|
#define CMD2_UBITS 0x10
|
|
|
|
static BITCMD *addcmd (BITCMD *, int, int, int, u_int);
|
|
static void compress_mode (BITCMD *);
|
|
#ifdef SETMODE_DEBUG
|
|
static void dumpmode (BITCMD *);
|
|
#endif
|
|
|
|
#ifndef HAVE_GETMODE
|
|
/*
|
|
* Given the old mode and an array of bitcmd structures, apply the operations
|
|
* described in the bitcmd structures to the old mode, and return the new mode.
|
|
* Note that there is no '=' command; a strict assignment is just a '-' (clear
|
|
* bits) followed by a '+' (set bits).
|
|
*/
|
|
mode_t
|
|
getmode(bbox, omode)
|
|
const void *bbox;
|
|
mode_t omode;
|
|
{
|
|
const BITCMD *set;
|
|
mode_t clrval, newmode, value;
|
|
|
|
_DIAGASSERT(bbox != NULL);
|
|
|
|
set = (const BITCMD *)bbox;
|
|
newmode = omode;
|
|
for (value = 0;; set++)
|
|
switch(set->cmd) {
|
|
/*
|
|
* When copying the user, group or other bits around, we "know"
|
|
* where the bits are in the mode so that we can do shifts to
|
|
* copy them around. If we don't use shifts, it gets real
|
|
* grundgy with lots of single bit checks and bit sets.
|
|
*/
|
|
case 'u':
|
|
value = (newmode & S_IRWXU) >> 6;
|
|
goto common;
|
|
|
|
case 'g':
|
|
value = (newmode & S_IRWXG) >> 3;
|
|
goto common;
|
|
|
|
case 'o':
|
|
value = newmode & S_IRWXO;
|
|
common: if (set->cmd2 & CMD2_CLR) {
|
|
clrval =
|
|
(set->cmd2 & CMD2_SET) ? S_IRWXO : value;
|
|
if (set->cmd2 & CMD2_UBITS)
|
|
newmode &= ~((clrval<<6) & set->bits);
|
|
if (set->cmd2 & CMD2_GBITS)
|
|
newmode &= ~((clrval<<3) & set->bits);
|
|
if (set->cmd2 & CMD2_OBITS)
|
|
newmode &= ~(clrval & set->bits);
|
|
}
|
|
if (set->cmd2 & CMD2_SET) {
|
|
if (set->cmd2 & CMD2_UBITS)
|
|
newmode |= (value<<6) & set->bits;
|
|
if (set->cmd2 & CMD2_GBITS)
|
|
newmode |= (value<<3) & set->bits;
|
|
if (set->cmd2 & CMD2_OBITS)
|
|
newmode |= value & set->bits;
|
|
}
|
|
break;
|
|
|
|
case '+':
|
|
newmode |= set->bits;
|
|
break;
|
|
|
|
case '-':
|
|
newmode &= ~set->bits;
|
|
break;
|
|
|
|
case 'X':
|
|
if (omode & (S_IFDIR|S_IXUSR|S_IXGRP|S_IXOTH))
|
|
newmode |= set->bits;
|
|
break;
|
|
|
|
case '\0':
|
|
default:
|
|
#ifdef SETMODE_DEBUG
|
|
(void)printf("getmode:%04o -> %04o\n", omode, newmode);
|
|
#endif
|
|
return (newmode);
|
|
}
|
|
}
|
|
#endif /* HAVE_GETMODE */
|
|
|
|
#ifndef HAVE_SETMODE
|
|
#define ADDCMD(a, b, c, d) do { \
|
|
if (set >= endset) { \
|
|
BITCMD *newset; \
|
|
setlen += SET_LEN_INCR; \
|
|
newset = realloc(saveset, sizeof(BITCMD) * setlen); \
|
|
if (newset == NULL) { \
|
|
free(saveset); \
|
|
return (NULL); \
|
|
} \
|
|
set = newset + (set - saveset); \
|
|
saveset = newset; \
|
|
endset = newset + (setlen - 2); \
|
|
} \
|
|
set = addcmd(set, (a), (b), (c), (d)); \
|
|
} while (/*CONSTCOND*/0)
|
|
|
|
#define STANDARD_BITS (S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO)
|
|
|
|
void *
|
|
setmode(p)
|
|
const char *p;
|
|
{
|
|
int perm, who;
|
|
char op, *ep;
|
|
BITCMD *set, *saveset, *endset;
|
|
sigset_t sigset, sigoset;
|
|
mode_t mask;
|
|
int equalopdone = 0; /* pacify gcc */
|
|
int permXbits, setlen;
|
|
|
|
if (!*p)
|
|
return (NULL);
|
|
|
|
/*
|
|
* Get a copy of the mask for the permissions that are mask relative.
|
|
* Flip the bits, we want what's not set. Since it's possible that
|
|
* the caller is opening files inside a signal handler, protect them
|
|
* as best we can.
|
|
*/
|
|
sigfillset(&sigset);
|
|
(void)sigprocmask(SIG_BLOCK, &sigset, &sigoset);
|
|
(void)umask(mask = umask(0));
|
|
mask = ~mask;
|
|
(void)sigprocmask(SIG_SETMASK, &sigoset, NULL);
|
|
|
|
setlen = SET_LEN + 2;
|
|
|
|
if ((set = malloc((u_int)(sizeof(BITCMD) * setlen))) == NULL)
|
|
return (NULL);
|
|
saveset = set;
|
|
endset = set + (setlen - 2);
|
|
|
|
/*
|
|
* If an absolute number, get it and return; disallow non-octal digits
|
|
* or illegal bits.
|
|
*/
|
|
if (isdigit((unsigned char)*p)) {
|
|
perm = (mode_t)strtol(p, &ep, 8);
|
|
if (*ep || perm & ~(STANDARD_BITS|S_ISTXT)) {
|
|
free(saveset);
|
|
return (NULL);
|
|
}
|
|
ADDCMD('=', (STANDARD_BITS|S_ISTXT), perm, mask);
|
|
set->cmd = 0;
|
|
return (saveset);
|
|
}
|
|
|
|
/*
|
|
* Build list of structures to set/clear/copy bits as described by
|
|
* each clause of the symbolic mode.
|
|
*/
|
|
for (;;) {
|
|
/* First, find out which bits might be modified. */
|
|
for (who = 0;; ++p) {
|
|
switch (*p) {
|
|
case 'a':
|
|
who |= STANDARD_BITS;
|
|
break;
|
|
case 'u':
|
|
who |= S_ISUID|S_IRWXU;
|
|
break;
|
|
case 'g':
|
|
who |= S_ISGID|S_IRWXG;
|
|
break;
|
|
case 'o':
|
|
who |= S_IRWXO;
|
|
break;
|
|
default:
|
|
goto getop;
|
|
}
|
|
}
|
|
|
|
getop: if ((op = *p++) != '+' && op != '-' && op != '=') {
|
|
free(saveset);
|
|
return (NULL);
|
|
}
|
|
if (op == '=')
|
|
equalopdone = 0;
|
|
|
|
who &= ~S_ISTXT;
|
|
for (perm = 0, permXbits = 0;; ++p) {
|
|
switch (*p) {
|
|
case 'r':
|
|
perm |= S_IRUSR|S_IRGRP|S_IROTH;
|
|
break;
|
|
case 's':
|
|
/*
|
|
* If specific bits where requested and
|
|
* only "other" bits ignore set-id.
|
|
*/
|
|
if (who == 0 || (who & ~S_IRWXO))
|
|
perm |= S_ISUID|S_ISGID;
|
|
break;
|
|
case 't':
|
|
/*
|
|
* If specific bits where requested and
|
|
* only "other" bits ignore set-id.
|
|
*/
|
|
if (who == 0 || (who & ~S_IRWXO)) {
|
|
who |= S_ISTXT;
|
|
perm |= S_ISTXT;
|
|
}
|
|
break;
|
|
case 'w':
|
|
perm |= S_IWUSR|S_IWGRP|S_IWOTH;
|
|
break;
|
|
case 'X':
|
|
permXbits = S_IXUSR|S_IXGRP|S_IXOTH;
|
|
break;
|
|
case 'x':
|
|
perm |= S_IXUSR|S_IXGRP|S_IXOTH;
|
|
break;
|
|
case 'u':
|
|
case 'g':
|
|
case 'o':
|
|
/*
|
|
* When ever we hit 'u', 'g', or 'o', we have
|
|
* to flush out any partial mode that we have,
|
|
* and then do the copying of the mode bits.
|
|
*/
|
|
if (perm) {
|
|
ADDCMD(op, who, perm, mask);
|
|
perm = 0;
|
|
}
|
|
if (op == '=')
|
|
equalopdone = 1;
|
|
if (op == '+' && permXbits) {
|
|
ADDCMD('X', who, permXbits, mask);
|
|
permXbits = 0;
|
|
}
|
|
ADDCMD(*p, who, op, mask);
|
|
break;
|
|
|
|
default:
|
|
/*
|
|
* Add any permissions that we haven't already
|
|
* done.
|
|
*/
|
|
if (perm || (op == '=' && !equalopdone)) {
|
|
if (op == '=')
|
|
equalopdone = 1;
|
|
ADDCMD(op, who, perm, mask);
|
|
perm = 0;
|
|
}
|
|
if (permXbits) {
|
|
ADDCMD('X', who, permXbits, mask);
|
|
permXbits = 0;
|
|
}
|
|
goto apply;
|
|
}
|
|
}
|
|
|
|
apply: if (!*p)
|
|
break;
|
|
if (*p != ',')
|
|
goto getop;
|
|
++p;
|
|
}
|
|
set->cmd = 0;
|
|
#ifdef SETMODE_DEBUG
|
|
(void)printf("Before compress_mode()\n");
|
|
dumpmode(saveset);
|
|
#endif
|
|
compress_mode(saveset);
|
|
#ifdef SETMODE_DEBUG
|
|
(void)printf("After compress_mode()\n");
|
|
dumpmode(saveset);
|
|
#endif
|
|
return (saveset);
|
|
}
|
|
|
|
static BITCMD *
|
|
addcmd(set, op, who, oparg, mask)
|
|
BITCMD *set;
|
|
int oparg, who;
|
|
int op;
|
|
u_int mask;
|
|
{
|
|
|
|
_DIAGASSERT(set != NULL);
|
|
|
|
switch (op) {
|
|
case '=':
|
|
set->cmd = '-';
|
|
set->bits = who ? who : STANDARD_BITS;
|
|
set++;
|
|
|
|
op = '+';
|
|
/* FALLTHROUGH */
|
|
case '+':
|
|
case '-':
|
|
case 'X':
|
|
set->cmd = op;
|
|
set->bits = (who ? who : mask) & oparg;
|
|
break;
|
|
|
|
case 'u':
|
|
case 'g':
|
|
case 'o':
|
|
set->cmd = op;
|
|
if (who) {
|
|
set->cmd2 = ((who & S_IRUSR) ? CMD2_UBITS : 0) |
|
|
((who & S_IRGRP) ? CMD2_GBITS : 0) |
|
|
((who & S_IROTH) ? CMD2_OBITS : 0);
|
|
set->bits = (mode_t)~0;
|
|
} else {
|
|
set->cmd2 = CMD2_UBITS | CMD2_GBITS | CMD2_OBITS;
|
|
set->bits = mask;
|
|
}
|
|
|
|
if (oparg == '+')
|
|
set->cmd2 |= CMD2_SET;
|
|
else if (oparg == '-')
|
|
set->cmd2 |= CMD2_CLR;
|
|
else if (oparg == '=')
|
|
set->cmd2 |= CMD2_SET|CMD2_CLR;
|
|
break;
|
|
}
|
|
return (set + 1);
|
|
}
|
|
|
|
#ifdef SETMODE_DEBUG
|
|
static void
|
|
dumpmode(set)
|
|
BITCMD *set;
|
|
{
|
|
|
|
_DIAGASSERT(set != NULL);
|
|
|
|
for (; set->cmd; ++set)
|
|
(void)printf("cmd: '%c' bits %04o%s%s%s%s%s%s\n",
|
|
set->cmd, set->bits, set->cmd2 ? " cmd2:" : "",
|
|
set->cmd2 & CMD2_CLR ? " CLR" : "",
|
|
set->cmd2 & CMD2_SET ? " SET" : "",
|
|
set->cmd2 & CMD2_UBITS ? " UBITS" : "",
|
|
set->cmd2 & CMD2_GBITS ? " GBITS" : "",
|
|
set->cmd2 & CMD2_OBITS ? " OBITS" : "");
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Given an array of bitcmd structures, compress by compacting consecutive
|
|
* '+', '-' and 'X' commands into at most 3 commands, one of each. The 'u',
|
|
* 'g' and 'o' commands continue to be separate. They could probably be
|
|
* compacted, but it's not worth the effort.
|
|
*/
|
|
static void
|
|
compress_mode(set)
|
|
BITCMD *set;
|
|
{
|
|
BITCMD *nset;
|
|
int setbits, clrbits, Xbits, op;
|
|
|
|
_DIAGASSERT(set != NULL);
|
|
|
|
for (nset = set;;) {
|
|
/* Copy over any 'u', 'g' and 'o' commands. */
|
|
while ((op = nset->cmd) != '+' && op != '-' && op != 'X') {
|
|
*set++ = *nset++;
|
|
if (!op)
|
|
return;
|
|
}
|
|
|
|
for (setbits = clrbits = Xbits = 0;; nset++) {
|
|
if ((op = nset->cmd) == '-') {
|
|
clrbits |= nset->bits;
|
|
setbits &= ~nset->bits;
|
|
Xbits &= ~nset->bits;
|
|
} else if (op == '+') {
|
|
setbits |= nset->bits;
|
|
clrbits &= ~nset->bits;
|
|
Xbits &= ~nset->bits;
|
|
} else if (op == 'X')
|
|
Xbits |= nset->bits & ~setbits;
|
|
else
|
|
break;
|
|
}
|
|
if (clrbits) {
|
|
set->cmd = '-';
|
|
set->cmd2 = 0;
|
|
set->bits = clrbits;
|
|
set++;
|
|
}
|
|
if (setbits) {
|
|
set->cmd = '+';
|
|
set->cmd2 = 0;
|
|
set->bits = setbits;
|
|
set++;
|
|
}
|
|
if (Xbits) {
|
|
set->cmd = 'X';
|
|
set->cmd2 = 0;
|
|
set->bits = Xbits;
|
|
set++;
|
|
}
|
|
}
|
|
}
|
|
#endif /* !HAVE_SETMODE */
|