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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:21:29 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:21:29 +0000 |
commit | 29cd838eab01ed7110f3ccb2e8c6a35c8a31dbcc (patch) | |
tree | 63ef546b10a81d461e5cf5ed9e98a68cd7dee1aa /src/kash/setmode.c | |
parent | Initial commit. (diff) | |
download | kbuild-29cd838eab01ed7110f3ccb2e8c6a35c8a31dbcc.tar.xz kbuild-29cd838eab01ed7110f3ccb2e8c6a35c8a31dbcc.zip |
Adding upstream version 1:0.1.9998svn3589+dfsg.upstream/1%0.1.9998svn3589+dfsg
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/kash/setmode.c')
-rw-r--r-- | src/kash/setmode.c | 472 |
1 files changed, 472 insertions, 0 deletions
diff --git a/src/kash/setmode.c b/src/kash/setmode.c new file mode 100644 index 0000000..02fa1f9 --- /dev/null +++ b/src/kash/setmode.c @@ -0,0 +1,472 @@ +/* $NetBSD: setmode.c,v 1.30 2003/08/07 16:42:56 agc 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 0 +#if defined(LIBC_SCCS) && !defined(lint) +static char sccsid[] = "@(#)setmode.c 8.2 (Berkeley) 3/25/94"; +#else +__RCSID("$NetBSD: setmode.c,v 1.30 2003/08/07 16:42:56 agc Exp $"); +#endif /* LIBC_SCCS and not lint */ +#endif + +#include <sys/types.h> +#include <sys/stat.h> + +#include <ctype.h> +#include <errno.h> +#include <stdlib.h> +#include "shinstance.h" /* for unistd.h types/defines */ + +#ifdef SETMODE_DEBUG +#include <stdio.h> +#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, unsigned int); +static void compress_mode(BITCMD *); +#ifdef SETMODE_DEBUG +static void dumpmode(BITCMD *); +#endif + +#ifndef _DIAGASSERT +# define _DIAGASSERT kHlpAssert +#endif + +#ifndef S_ISTXT +# ifdef S_ISVTX +# define S_ISTXT S_ISVTX +# else +# define S_ISTXT 0 +# endif +#endif /* !S_ISTXT */ + +/* + * 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 +kash_getmode(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); + } +} + +#define ADDCMD(a, b, c, d) do { \ + if (set >= endset) { \ + BITCMD *newset; \ + setlen += SET_LEN_INCR; \ + newset = sh_realloc(NULL, saveset, sizeof(BITCMD) * setlen); \ + if (newset == NULL) { \ + sh_free(NULL, 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 * +kash_setmode(shinstance *psh, const char *p) +{ + int perm, who; + char op, *ep; + BITCMD *set, *saveset, *endset; + 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. + */ + mask = shfile_get_umask(&psh->fdtab); + + setlen = SET_LEN + 2; + + if ((set = sh_malloc(NULL, 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)) { + sh_free(NULL, 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 != '=') { + sh_free(NULL, 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; + unsigned 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 ? (unsigned int)who : mask) & (unsigned int)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++; + } + } +} |