libmisc/shell/main_cmdchown.c

0001 /*
0002  * Copyright (c) 2014 embedded brains GmbH & Co. KG
0003  *
0004  * The license and distribution terms for this file may be
0005  * found in the file LICENSE in this distribution or at
0006  * http://www.rtems.org/license/LICENSE.
0007  */
0008
0009 #ifdef HAVE_CONFIG_H
0010 #include "config.h"
0011 #endif
0012
0013 #include <errno.h>
0014 #include <limits.h>
0015 #include <stdio.h>
0016 #include <string.h>
0017 #include <unistd.h>
0018
0019 #include <rtems/shellconfig.h>
0020
0021 #include "internal.h"
0022
0023 static int usage(void)
0024 {
0025   puts(rtems_shell_CMDCHOWN_Command.usage);
0026
0027   return -1;
0028 }
0029
0030 static void error(const char *s, int eno)
0031 {
0032   printf("%s: %s\n", s, strerror(eno));
0033 }
0034
0035 static int rtems_shell_main_cmdchown(int argc, char **argv)
0036 {
0037   if (argc >= 2) {
0038     const char *s = argv[1];
0039     unsigned new_uid = UINT_MAX;
0040     unsigned new_gid = UINT_MAX;
0041     bool change_uid = false;
0042     bool change_gid = false;
0043     uid_t task_uid;
0044     int i;
0045
0046     if (strcmp(s, ":") != 0) {
0047       int n = sscanf(argv[1], "%u:%u", &new_uid, &new_gid);
0048
0049       if (n == 2) {
0050         change_uid = true;
0051         change_gid = true;
0052       } else if (n == 1) {
0053         change_uid = true;
0054       } else {
0055         n = sscanf(argv[1], ":%u", &new_gid);
0056
0057         if (n == 1) {
0058           change_gid = true;
0059         } else {
0060           return usage();
0061         }
0062       }
0063     }
0064
0065     task_uid = getuid();
0066
0067     for (i = 2; i < argc; ++i) {
0068       const char *cmd = argv[i];
0069       rtems_shell_cmd_t *shell_cmd = rtems_shell_lookup_cmd(cmd);
0070
0071       if (shell_cmd != NULL) {
0072         if (task_uid == 0 || task_uid == shell_cmd->uid) {
0073           if (change_uid) {
0074             shell_cmd->uid = new_uid;
0075           }
0076
0077           if (change_gid) {
0078             shell_cmd->gid = new_gid;
0079           }
0080         } else if (rtems_shell_can_see_cmd(shell_cmd)) {
0081           error(cmd, EACCES);
0082         } else {
0083           error(cmd, ENOENT);
0084         }
0085       } else {
0086         error(cmd, ENOENT);
0087       }
0088     }
0089   } else {
0090     return usage();
0091   }
0092
0093   return 0;
0094 }
0095
0096 rtems_shell_cmd_t rtems_shell_CMDCHOWN_Command = {
0097   .name = "cmdchown",
0098   .usage = "cmdchown [OWNER][:[GROUP]] COMMAND...",
0099   .topic = "misc",
0100   .command = rtems_shell_main_cmdchown
0101 };