mirror of
				https://github.com/Bandie/grub2-signing-extension.git
				synced 2024-04-01 15:51:26 +00:00 
			
		
		
		
	- Use native bash math where doing so improves readability. - Avoid illegal exit status codes (666 in impossible scenario). - Avoid useless use of cat (`cat foo | bar` vs the more efficient `bar <foo`). - Avoid needless echo pipelines (`echo foo | bar` vs `bar <<<"$foo"`). - Never use a for loop to iterate over output from `find`; `for` loops depend on string-splitting, which is only available with globbing behavior. See http://mywiki.wooledge.org/DontReadLinesWithFor - Use `read -s` to silence feedback rather than playing around with `stty`. - Use `tput` to retrieve color codes correct for the current terminal rather than assuming a terminal compatible with ANSI color codes. - Use a expression compatible with BSD `tr` in "passphrase-shredding" code. (BTW, I very much doubt that this code actually does any good; it's not a reasonable expectation that a new string assigned to a variable will actually be placed at the same location in memory). - Implementations of `echo` which do anything other than print `-e` on output when `echo -e` is run are nonconformant with the POSIX spec for echo. Similarly, `echo -n` behavior is not defined by the standard. Avoid relying on either of these. (See http://pubs.opengroup.org/onlinepubs/009604599/utilities/echo.html, particularly the APPLICATION USAGE section). - Always quote expansions to prevent string-splitting and glob-expansion (`"$i"`, not `$i`). - Avoid `some_command; if [ $? -eq 0 ]; then` when `if some_command; then` can be used instead.
		
			
				
	
	
		
			50 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			Bash
		
	
	
		
			Executable File
		
	
	
	
	
			
		
		
	
	
			50 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			Bash
		
	
	
		
			Executable File
		
	
	
	
	
#!/bin/bash
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# grub2-sign
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# Signs everything important in /boot. Depends on grub2-verify.
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# Author: Bandie Kojote
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# Licence: GNU-GPLv3
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# Running grub2-verify first to prevent double signing
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echo "Running grub2-verify to check if everything is unsigned..." >&2
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grub2-verify
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if (( $? < 2 )); then
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    echo "Run grub2-unsign first." >&2
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    exit 1
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fi
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# Ask for passphrase
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IFS= read -r -s -p 'Passphrase: ' pp
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# build a find command line matching relevant filenames
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name_patterns=(
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	grubenv				# fixed names
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	'*.'{cfg,lst,mod,asc,pf2}	# names with interesting extensions
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	{vmlinuz,initrd}'*'		# names with interesting prefixes
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)
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find_args=( '-false' )
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for pattern in "${name_patterns[@]}"; do find_args+=( '-or' '-name' "$pattern" ); done
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# Find GRUB2 datas
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while IFS= read -r -d '' i; do
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    # Signing
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    if gpg --batch --detach-sign --passphrase-fd 0 "$i" <<<"$pp"; then
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        echo "$i signed." >&2
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    else
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        echo "ERROR!" >&2
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	break
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    fi
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done < <(find /boot '(' "${find_args[@]}" ')' '-print0' )
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# Shredding passphrase
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if (( ${#pp} )); then
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    echo "Shredding passphrase..." >&2
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    for (( i=0; i<10; i++ )); do
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	pp=$(LC_ALL=C tr -cd '[:print:]' </dev/urandom | head -c ${#pp})
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    done
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fi
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echo "Done!" >&2
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exit 0
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