49 lines
1.7 KiB
Text
49 lines
1.7 KiB
Text
6.10 The Restricted Shell
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=========================
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If Bash is started with the name `rbash', or the `--restricted' or `-r'
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option is supplied at invocation, the shell becomes restricted. A
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restricted shell is used to set up an environment more controlled than
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the standard shell. A restricted shell behaves identically to `bash'
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with the exception that the following are disallowed or not performed:
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* Changing directories with the `cd' builtin.
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* Setting or unsetting the values of the `SHELL', `PATH', `ENV', or
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`BASH_ENV' variables.
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* Specifying command names containing slashes.
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* Specifying a filename containing a slash as an argument to the `.'
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builtin command.
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* Specifying a filename containing a slash as an argument to the `-p'
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option to the `hash' builtin command.
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* Importing function definitions from the shell environment at
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startup.
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* Parsing the value of `SHELLOPTS' from the shell environment at
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startup.
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* Redirecting output using the `>', `>|', `<>', `>&', `&>', and `>>'
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redirection operators.
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* Using the `exec' builtin to replace the shell with another command.
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* Adding or deleting builtin commands with the `-f' and `-d' options
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to the `enable' builtin.
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* Using the `enable' builtin command to enable disabled shell
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builtins.
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* Specifying the `-p' option to the `command' builtin.
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* Turning off restricted mode with `set +r' or `set +o restricted'.
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These restrictions are enforced after any startup files are read.
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When a command that is found to be a shell script is executed (*note
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Shell Scripts::), `rbash' turns off any restrictions in the shell
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spawned to execute the script.
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