diff options
| -rw-r--r-- | Makefile | 3 | ||||
| -rw-r--r-- | Versions | 4 | ||||
| -rw-r--r-- | include/bsd/stdlib.h | 9 | ||||
| -rw-r--r-- | man/setmode.3 | 114 | ||||
| -rw-r--r-- | src/setmode.c | 444 |
5 files changed, 573 insertions, 1 deletions
@@ -13,6 +13,7 @@ LIB_DIST := Makefile Versions libbsd.pc LIB_SRCS := arc4random.c bsd_getopt.c err.c fgetln.c heapsort.c \ humanize_number.c inet_net_pton.c \ hash/md5.c hash/md5hl.c \ + setmode.c \ strlcat.c strlcpy.c fmtcheck.c progname.c vis.c unvis.c LIB_SRCS := $(patsubst %,src/%,$(LIB_SRCS)) @@ -23,7 +24,7 @@ LIB_GEN_SRCS := \ LIB_INCLUDES := bsd/err.h bsd/getopt.h bsd/ip_icmp.h bsd/random.h bsd/queue.h bsd/md5.h bsd/string.h \ bsd/bsd.h bsd/cdefs.h bsd/stdlib.h vis.h libutil.h -LIB_MANS := arc4random.3 strlcpy.3 fgetln.3 fmtcheck.3 md5.3 +LIB_MANS := arc4random.3 strlcpy.3 fgetln.3 fmtcheck.3 setmode.3 md5.3 LIB_MANS := $(patsubst %,man/%,$(LIB_MANS)) LIB_STATIC_OBJS = $(LIB_SRCS:%.c=%.o) @@ -15,6 +15,10 @@ LIBBSD_0.0 { getprogname; setprogname; strlcpy; strlcat; + + setmode; + getmode; + vis; strvis; strvisx; unvis; strunvis; strunvisx; MD5Init; diff --git a/include/bsd/stdlib.h b/include/bsd/stdlib.h index f450e56..16376cb 100644 --- a/include/bsd/stdlib.h +++ b/include/bsd/stdlib.h @@ -1,6 +1,7 @@ /* * Copyright (C) 2005 Aurelien Jarno * Copyright (C) 2006 Robert Millan + * Copyright (C) 2008 Guillem Jover * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions @@ -28,6 +29,7 @@ #ifndef LIBBSD_STDLIB_H #define LIBBSD_STDLIB_H +#include <sys/stat.h> #include <stdlib.h> const char *fmtcheck (const char *, const char *); @@ -37,4 +39,11 @@ void setprogname (char *); int heapsort (void *, size_t, size_t, int (*)(const void *, const void *)); +#ifndef S_ISTXT +#define S_ISTXT S_ISVTX +#endif + +mode_t getmode(const void *set, mode_t mode); +void *setmode(const char *mode_str); + #endif diff --git a/man/setmode.3 b/man/setmode.3 new file mode 100644 index 0000000..94fd5d1 --- /dev/null +++ b/man/setmode.3 @@ -0,0 +1,114 @@ +.\" Copyright (c) 1989, 1991, 1993 +.\" The 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. +.\" 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. +.\" +.\" @(#)setmode.3 8.2 (Berkeley) 4/28/95 +.\" $FreeBSD: src/lib/libc/gen/setmode.3,v 1.12 2007/01/09 00:27:55 imp Exp $ +.\" +.Dd April 28, 1995 +.Dt SETMODE 3 +.Os +.Sh NAME +.Nm getmode , +.Nm setmode +.Nd modify mode bits +.Sh LIBRARY +.Lb libc +.Sh SYNOPSIS +.In unistd.h +.Ft mode_t +.Fn getmode "const void *set" "mode_t mode" +.Ft void * +.Fn setmode "const char *mode_str" +.Sh DESCRIPTION +The +.Fn getmode +function +returns a copy of the file permission bits +.Fa mode +as altered by the values pointed to by +.Fa set . +While only the mode bits are altered, other parts of the file mode +may be examined. +.Pp +The +.Fn setmode +function +takes an absolute (octal) or symbolic value, as described in +.Xr chmod 1 , +as an argument +and returns a pointer to mode values to be supplied to +.Fn getmode . +Because some of the symbolic values are relative to the file +creation mask, +.Fn setmode +may call +.Xr umask 2 . +If this occurs, the file creation mask will be restored before +.Fn setmode +returns. +If the calling program changes the value of its file creation mask +after calling +.Fn setmode , +.Fn setmode +must be called again if +.Fn getmode +is to modify future file modes correctly. +.Pp +If the mode passed to +.Fn setmode +is invalid or if memory cannot be allocated for the return value, +.Fn setmode +returns +.Dv NULL . +.Pp +The value returned from +.Fn setmode +is obtained from +.Fn malloc +and should be returned to the system with +.Fn free +when the program is done with it, generally after a call to +.Fn getmode . +.Sh ERRORS +The +.Fn setmode +function +may fail and set errno for any of the errors specified for the library +routine +.Xr malloc 3 . +.Sh SEE ALSO +.Xr chmod 1 , +.Xr stat 2 , +.Xr umask 2 , +.Xr malloc 3 +.Sh HISTORY +The +.Fn getmode +and +.Fn setmode +functions first appeared in +.Bx 4.4 . diff --git a/src/setmode.c b/src/setmode.c new file mode 100644 index 0000000..66f2924 --- /dev/null +++ b/src/setmode.c @@ -0,0 +1,444 @@ +/* + * 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. + * 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. + */ + +#if defined(LIBC_SCCS) && !defined(lint) +static char sccsid[] = "@(#)setmode.c 8.2 (Berkeley) 3/25/94"; +#endif /* LIBC_SCCS and not lint */ +#include <sys/cdefs.h> +__FBSDID("$FreeBSD: src/lib/libc/gen/setmode.c,v 1.11 2007/01/09 00:27:55 imp Exp $"); + +#include <sys/types.h> +#include <sys/stat.h> + +#include <ctype.h> +#include <signal.h> +#include <stddef.h> +#include <stdlib.h> +#include <unistd.h> + +#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, u_int); +static void compress_mode(BITCMD *); +#ifdef SETMODE_DEBUG +static void dumpmode(BITCMD *); +#endif + +/* + * 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(const void *bbox, mode_t omode) +{ + const BITCMD *set; + mode_t clrval, newmode, value; + + 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) \ + if (set >= endset) { \ + BITCMD *newset; \ + setlen += SET_LEN_INCR; \ + newset = realloc(saveset, sizeof(BITCMD) * setlen); \ + if (!newset) { \ + if (saveset) \ + free(saveset); \ + saveset = NULL; \ + return (NULL); \ + } \ + set = newset + (set - saveset); \ + saveset = newset; \ + endset = newset + (setlen - 2); \ + } \ + set = addcmd(set, (a), (b), (c), (d)) + +#define STANDARD_BITS (S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO) + +void * +setmode(const char *p) +{ + int perm, who; + char op, *ep; + BITCMD *set, *saveset, *endset; + sigset_t sigset, sigoset; + mode_t mask; + int equalopdone=0, permXbits, setlen; + long perml; + + 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)) { + perml = strtol(p, &ep, 8); + if (*ep || perml < 0 || perml & ~(STANDARD_BITS|S_ISTXT)) { + free(saveset); + return (NULL); + } + perm = (mode_t)perml; + 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 only "other" bits ignore set-id. */ + if (!who || who & ~S_IRWXO) + perm |= S_ISUID|S_ISGID; + break; + case 't': + /* If only "other" bits ignore sticky. */ + if (!who || 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(BITCMD *set, int op, int who, int oparg, u_int mask) +{ + 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(BITCMD *set) +{ + 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(BITCMD *set) +{ + BITCMD *nset; + int setbits, clrbits, Xbits, op; + + 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++; + } + } +} |