diff options
Diffstat (limited to 'coreutils/chmod.c')
-rw-r--r-- | coreutils/chmod.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/coreutils/chmod.c b/coreutils/chmod.c new file mode 100644 index 0000000..40f681f --- /dev/null +++ b/coreutils/chmod.c @@ -0,0 +1,160 @@ +/* vi: set sw=4 ts=4: */ +/* + * Mini chmod implementation for busybox + * + * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org> + * + * Reworked by (C) 2002 Vladimir Oleynik <dzo@simtreas.ru> + * to correctly parse '-rwxgoa' + * + * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. + */ + +/* BB_AUDIT SUSv3 compliant */ +/* BB_AUDIT GNU defects - unsupported long options. */ +/* http://www.opengroup.org/onlinepubs/007904975/utilities/chmod.html */ + +#include "libbb.h" + +/* This is a NOEXEC applet. Be very careful! */ + + +#define OPT_RECURSE (option_mask32 & 1) +#define OPT_VERBOSE (USE_DESKTOP(option_mask32 & 2) SKIP_DESKTOP(0)) +#define OPT_CHANGED (USE_DESKTOP(option_mask32 & 4) SKIP_DESKTOP(0)) +#define OPT_QUIET (USE_DESKTOP(option_mask32 & 8) SKIP_DESKTOP(0)) +#define OPT_STR "R" USE_DESKTOP("vcf") + +/* coreutils: + * chmod never changes the permissions of symbolic links; the chmod + * system call cannot change their permissions. This is not a problem + * since the permissions of symbolic links are never used. + * However, for each symbolic link listed on the command line, chmod changes + * the permissions of the pointed-to file. In contrast, chmod ignores + * symbolic links encountered during recursive directory traversals. + */ + +static int FAST_FUNC fileAction(const char *fileName, struct stat *statbuf, void* param, int depth) +{ + mode_t newmode; + + /* match coreutils behavior */ + if (depth == 0) { + /* statbuf holds lstat result, but we need stat (follow link) */ + if (stat(fileName, statbuf)) + goto err; + } else { /* depth > 0: skip links */ + if (S_ISLNK(statbuf->st_mode)) + return TRUE; + } + newmode = statbuf->st_mode; + + if (!bb_parse_mode((char *)param, &newmode)) + bb_error_msg_and_die("invalid mode: %s", (char *)param); + + if (chmod(fileName, newmode) == 0) { + if (OPT_VERBOSE + || (OPT_CHANGED && statbuf->st_mode != newmode) + ) { + printf("mode of '%s' changed to %04o (%s)\n", fileName, + newmode & 07777, bb_mode_string(newmode)+1); + } + return TRUE; + } + err: + if (!OPT_QUIET) + bb_simple_perror_msg(fileName); + return FALSE; +} + +int chmod_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; +int chmod_main(int argc UNUSED_PARAM, char **argv) +{ + int retval = EXIT_SUCCESS; + char *arg, **argp; + char *smode; + + /* Convert first encountered -r into ar, -w into aw etc + * so that getopt would not eat it */ + argp = argv; + while ((arg = *++argp)) { + /* Mode spec must be the first arg (sans -R etc) */ + /* (protect against mishandling e.g. "chmod 644 -r") */ + if (arg[0] != '-') { + arg = NULL; + break; + } + /* An option. Not a -- or valid option? */ + if (arg[1] && !strchr("-"OPT_STR, arg[1])) { + arg[0] = 'a'; + break; + } + } + + /* Parse options */ + opt_complementary = "-2"; + getopt32(argv, ("-"OPT_STR) + 1); /* Reuse string */ + argv += optind; + + /* Restore option-like mode if needed */ + if (arg) arg[0] = '-'; + + /* Ok, ready to do the deed now */ + smode = *argv++; + do { + if (!recursive_action(*argv, + OPT_RECURSE, // recurse + fileAction, // file action + fileAction, // dir action + smode, // user data + 0) // depth + ) { + retval = EXIT_FAILURE; + } + } while (*++argv); + + return retval; +} + +/* +Security: chmod is too important and too subtle. +This is a test script (busybox chmod versus coreutils). +Run it in empty directory. + +#!/bin/sh +t1="/tmp/busybox chmod" +t2="/usr/bin/chmod" +create() { + rm -rf $1; mkdir $1 + ( + cd $1 || exit 1 + mkdir dir + >up + >file + >dir/file + ln -s dir linkdir + ln -s file linkfile + ln -s ../up dir/up + ) +} +tst() { + (cd test1; $t1 $1) + (cd test2; $t2 $1) + (cd test1; ls -lR) >out1 + (cd test2; ls -lR) >out2 + echo "chmod $1" >out.diff + if ! diff -u out1 out2 >>out.diff; then exit 1; fi + rm out.diff +} +echo "If script produced 'out.diff' file, then at least one testcase failed" +create test1; create test2 +tst "a+w file" +tst "a-w dir" +tst "a+w linkfile" +tst "a-w linkdir" +tst "-R a+w file" +tst "-R a-w dir" +tst "-R a+w linkfile" +tst "-R a-w linkdir" +tst "a-r,a+x linkfile" +*/ |