selinux/chcon.c

   1 /*
   2  * chcon -- change security context, based on coreutils-5.97-13
   3  *
   4  * Port to busybox: KaiGai Kohei <kaigai@kaigai.gr.jp>
   5  *
   6  * Copyright (C) 2006 - 2007 KaiGai Kohei <kaigai@kaigai.gr.jp>
   7  *
   8  * Licensed under GPLv2, see file LICENSE in this source tree.
   9  */
  10
  11 //usage:#define chcon_trivial_usage
  12 //usage:       "[OPTIONS] CONTEXT FILE..."
  13 //usage:       "\n      chcon [OPTIONS] [-u USER] [-r ROLE] [-l RANGE] [-t TYPE] FILE..."
  14 //usage:        IF_FEATURE_CHCON_LONG_OPTIONS(
  15 //usage:       "\n      chcon [OPTIONS] --reference=RFILE FILE..."
  16 //usage:        )
  17 //usage:#define chcon_full_usage "\n\n"
  18 //usage:       "Change the security context of each FILE to CONTEXT\n"
  19 //usage:        IF_FEATURE_CHCON_LONG_OPTIONS(
  20 //usage:     "\n        -v,--verbose            Verbose"
  21 //usage:     "\n        -c,--changes            Report changes made"
  22 //usage:     "\n        -h,--no-dereference     Affect symlinks instead of their targets"
  23 //usage:     "\n        -f,--silent,--quiet     Suppress most error messages"
  24 //usage:     "\n        --reference=RFILE       Use RFILE's group instead of using a CONTEXT value"
  25 //usage:     "\n        -u,--user=USER          Set user/role/type/range in the target"
  26 //usage:     "\n        -r,--role=ROLE          security context"
  27 //usage:     "\n        -t,--type=TYPE"
  28 //usage:     "\n        -l,--range=RANGE"
  29 //usage:     "\n        -R,--recursive          Recurse"
  30 //usage:        )
  31 //usage:        IF_NOT_FEATURE_CHCON_LONG_OPTIONS(
  32 //usage:     "\n        -v      Verbose"
  33 //usage:     "\n        -c      Report changes made"
  34 //usage:     "\n        -h      Affect symlinks instead of their targets"
  35 //usage:     "\n        -f      Suppress most error messages"
  36 //usage:     "\n        -u USER Set user/role/type/range in the target security context"
  37 //usage:     "\n        -r ROLE"
  38 //usage:     "\n        -t TYPE"
  39 //usage:     "\n        -l RNG"
  40 //usage:     "\n        -R      Recurse"
  41 //usage:        )
  42
  43 #include <selinux/context.h>
  44
  45 #include "libbb.h"
  46
  47 #define OPT_RECURSIVE           (1<<0)  /* 'R' */
  48 #define OPT_CHANHES             (1<<1)  /* 'c' */
  49 #define OPT_NODEREFERENCE       (1<<2)  /* 'h' */
  50 #define OPT_QUIET               (1<<3)  /* 'f' */
  51 #define OPT_USER                (1<<4)  /* 'u' */
  52 #define OPT_ROLE                (1<<5)  /* 'r' */
  53 #define OPT_TYPE                (1<<6)  /* 't' */
  54 #define OPT_RANGE               (1<<7)  /* 'l' */
  55 #define OPT_VERBOSE             (1<<8)  /* 'v' */
  56 #define OPT_REFERENCE           ((1<<9) * ENABLE_FEATURE_CHCON_LONG_OPTIONS)
  57 #define OPT_COMPONENT_SPECIFIED (OPT_USER | OPT_ROLE | OPT_TYPE | OPT_RANGE)
  58
  59 static char *user = NULL;
  60 static char *role = NULL;
  61 static char *type = NULL;
  62 static char *range = NULL;
  63 static char *specified_context = NULL;
  64
  65 static int FAST_FUNC change_filedir_context(
  66                 const char *fname,
  67                 struct stat *stbuf UNUSED_PARAM,
  68                 void *userData UNUSED_PARAM,
  69                 int depth UNUSED_PARAM)
  70 {
  71         context_t context = NULL;
  72         security_context_t file_context = NULL;
  73         security_context_t context_string;
  74         int rc = FALSE;
  75         int status = 0;
  76
  77         if (option_mask32 & OPT_NODEREFERENCE) {
  78                 status = lgetfilecon(fname, &file_context);
  79         } else {
  80                 status = getfilecon(fname, &file_context);
  81         }
  82         if (status < 0 && errno != ENODATA) {
  83                 if ((option_mask32 & OPT_QUIET) == 0)
  84                         bb_error_msg("can't obtain security context: %s", fname);
  85                 goto skip;
  86         }
  87
  88         if (file_context == NULL && specified_context == NULL) {
  89                 bb_error_msg("can't apply partial context to unlabeled file %s", fname);
  90                 goto skip;
  91         }
  92
  93         if (specified_context == NULL) {
  94                 context = set_security_context_component(file_context,
  95                                                         user, role, type, range);
  96                 if (!context) {
  97                         bb_error_msg("can't compute security context from %s", file_context);
  98                         goto skip;
  99                 }
 100         } else {
 101                 context = context_new(specified_context);
 102                 if (!context) {
 103                         bb_error_msg("invalid context: %s", specified_context);
 104                         goto skip;
 105                 }
 106         }
 107
 108         context_string = context_str(context);
 109         if (!context_string) {
 110                 bb_error_msg("can't obtain security context in text expression");
 111                 goto skip;
 112         }
 113
 114         if (file_context == NULL || strcmp(context_string, file_context) != 0) {
 115                 int fail;
 116
 117                 if (option_mask32 & OPT_NODEREFERENCE) {
 118                         fail = lsetfilecon(fname, context_string);
 119                 } else {
 120                         fail = setfilecon(fname, context_string);
 121                 }
 122                 if ((option_mask32 & OPT_VERBOSE) || ((option_mask32 & OPT_CHANHES) && !fail)) {
 123                         printf(!fail
 124                                 ? "context of %s changed to %s\n"
 125                                 : "can't change context of %s to %s\n",
 126                                 fname, context_string);
 127                 }
 128                 if (!fail) {
 129                         rc = TRUE;
 130                 } else if ((option_mask32 & OPT_QUIET) == 0) {
 131                         bb_error_msg("can't change context of %s to %s",
 132                                         fname, context_string);
 133                 }
 134         } else if (option_mask32 & OPT_VERBOSE) {
 135                 printf("context of %s retained as %s\n", fname, context_string);
 136                 rc = TRUE;
 137         }
 138 skip:
 139         context_free(context);
 140         freecon(file_context);
 141
 142         return rc;
 143 }
 144
 145 #if ENABLE_FEATURE_CHCON_LONG_OPTIONS
 146 static const char chcon_longopts[] ALIGN1 =
 147         "recursive\0"      No_argument       "R"
 148         "changes\0"        No_argument       "c"
 149         "no-dereference\0" No_argument       "h"
 150         "silent\0"         No_argument       "f"
 151         "quiet\0"          No_argument       "f"
 152         "user\0"           Required_argument "u"
 153         "role\0"           Required_argument "r"
 154         "type\0"           Required_argument "t"
 155         "range\0"          Required_argument "l"
 156         "verbose\0"        No_argument       "v"
 157         "reference\0"      Required_argument "\xff" /* no short option */
 158         ;
 159 #endif
 160
 161 int chcon_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 162 int chcon_main(int argc UNUSED_PARAM, char **argv)
 163 {
 164         char *reference_file;
 165         char *fname;
 166         int i, errors = 0;
 167
 168 #if ENABLE_FEATURE_CHCON_LONG_OPTIONS
 169         applet_long_options = chcon_longopts;
 170 #endif
 171         opt_complementary = "-1"  /* at least 1 param */
 172                 ":?"  /* error if exclusivity constraints are violated */
 173 #if ENABLE_FEATURE_CHCON_LONG_OPTIONS
 174                 ":\xff--urtl:u--\xff:r--\xff:t--\xff:l--\xff"
 175 #endif
 176                 ":f--v:v--f";  /* 'verbose' and 'quiet' are exclusive */
 177         getopt32(argv, "Rchfu:r:t:l:v",
 178                 &user, &role, &type, &range, &reference_file);
 179         argv += optind;
 180
 181 #if ENABLE_FEATURE_CHCON_LONG_OPTIONS
 182         if (option_mask32 & OPT_REFERENCE) {
 183                 /* FIXME: lgetfilecon() should be used when '-h' is specified.
 184                  * But current implementation follows the original one. */
 185                 if (getfilecon(reference_file, &specified_context) < 0)
 186                         bb_perror_msg_and_die("getfilecon('%s') failed", reference_file);
 187         } else
 188 #endif
 189         if ((option_mask32 & OPT_COMPONENT_SPECIFIED) == 0) {
 190                 specified_context = *argv++;
 191                 /* specified_context is never NULL -
 192                  * "-1" in opt_complementary prevents this. */
 193                 if (!argv[0])
 194                         bb_error_msg_and_die("too few arguments");
 195         }
 196
 197         for (i = 0; (fname = argv[i]) != NULL; i++) {
 198                 int fname_len = strlen(fname);
 199                 while (fname_len > 1 && fname[fname_len - 1] == '/')
 200                         fname_len--;
 201                 fname[fname_len] = '\0';
 202
 203                 if (recursive_action(fname,
 204                                         1<<option_mask32 & OPT_RECURSIVE,
 205                                         change_filedir_context,
 206                                         change_filedir_context,
 207                                         NULL, 0) != TRUE)
 208                         errors = 1;
 209         }
 210         return errors;
 211 }