| Jari Aalto | 95732b4 | 2005-12-07 14:08:12 +0000 | [diff] [blame^] | 1 | 6.10 The Restricted Shell |
| 2 | ========================= |
| Jari Aalto | 7117c2d | 2002-07-17 14:10:11 +0000 | [diff] [blame] | 3 | |
| 4 | If Bash is started with the name `rbash', or the `--restricted' or `-r' |
| 5 | option is supplied at invocation, the shell becomes restricted. A |
| 6 | restricted shell is used to set up an environment more controlled than |
| 7 | the standard shell. A restricted shell behaves identically to `bash' |
| 8 | with the exception that the following are disallowed or not performed: |
| 9 | |
| 10 | * Changing directories with the `cd' builtin. |
| 11 | |
| 12 | * Setting or unsetting the values of the `SHELL', `PATH', `ENV', or |
| 13 | `BASH_ENV' variables. |
| 14 | |
| 15 | * Specifying command names containing slashes. |
| 16 | |
| 17 | * Specifying a filename containing a slash as an argument to the `.' |
| 18 | builtin command. |
| 19 | |
| 20 | * Specifying a filename containing a slash as an argument to the `-p' |
| 21 | option to the `hash' builtin command. |
| 22 | |
| 23 | * Importing function definitions from the shell environment at |
| 24 | startup. |
| 25 | |
| 26 | * Parsing the value of `SHELLOPTS' from the shell environment at |
| 27 | startup. |
| 28 | |
| 29 | * Redirecting output using the `>', `>|', `<>', `>&', `&>', and `>>' |
| 30 | redirection operators. |
| 31 | |
| 32 | * Using the `exec' builtin to replace the shell with another command. |
| 33 | |
| 34 | * Adding or deleting builtin commands with the `-f' and `-d' options |
| 35 | to the `enable' builtin. |
| 36 | |
| 37 | * Using the `enable' builtin command to enable disabled shell |
| 38 | builtins. |
| 39 | |
| 40 | * Specifying the `-p' option to the `command' builtin. |
| 41 | |
| 42 | * Turning off restricted mode with `set +r' or `set +o restricted'. |
| 43 | |
| 44 | These restrictions are enforced after any startup files are read. |
| 45 | |
| 46 | When a command that is found to be a shell script is executed (*note |
| 47 | Shell Scripts::), `rbash' turns off any restrictions in the shell |
| 48 | spawned to execute the script. |
| 49 | |