Using sed to input a grub MD5 bootloader password - sed

I am having issues using sed injecting a password into the grub.conf file.
Here is the syntax I am using:
sed -i /^timeout/s/$/"\npassword -md5 $1$ctuLL1$V4DZinO.4eTYjsGXOfU1F/" /boot/grub/grub.conf
Grub MD5:
$1$ctuLL1$V4DZinO.4eTYjsGXOfU1F/
Thanks for looking!

What I used seems to be working:
sed -i -e 's/timeout=5/timeout=0\'$'\npassword --md5 blah/g' /boot/grub/grub.conf
It is how I'm injecting a password during cobbler provisioning.
Obviously, you'll have to escape any special characters in the MD5 hash otherwise sed will complain.

Related

remove special character (^#) with sed

I want to remove "^#^#^#^#^#^#^#^#^#" from my textfile. I tried the following, but it did not work:
sed -i 's/\\^#//g' myfile.txt
sed is not generally robust against null characters. But Perl is, and tr:
tr -d '\000' <myfile.txt >newfile.txt
Some sed variants will be able to handle null bytes with the notation which works in Perl:
perl -i -pe 's/\x00//g' myfile.txt
The -i option says to replace the original file, like some sed variants also allow you to.
^# is one of the ways how to display the null byte. sed (at least the GNU one) represents it as \x00:
sed 's/\x00//g'

SED inplace file change inside make - How?

sed inplace change on a file is not working inside Make object.
I want to replace a line in a file with sed called in a make object. But it does not seem to be working. How can I fix this?
change_generics:
ifeq ($(run_TESTNAME), diagnostics)
ifeq ($(run_TESTCASE), 1)
sed -i -e "s/SIM_MULTI\==[a-z,A-Z]*/SIM_MULTI=TRUE/" ./generics.f
else ifeq ($(TESTCASE), 2)
sed -i -e "s/SIM_MISSED\==[a-z,A-Z]*/SIM_MISSED=TRUE/" ./generics.f
endif
endif
I would like the generics.f file changed with that one line change. But it remains the same as the original. The sed command works outside make.
I can't reproduce this using GNU sed 4.2.2 and GNU make 3.82, or at least, I can't reproduce any scenario where the same sed command works from the command line but not in a Makefile.
Simpler Makefile:
all:
# Contrived just so I can test your 2 sed commands.
sed -i -e "s/SIM_MULTI\==[a-z,A-Z]*/SIM_MULTI=TRUE/" ./generics.f
sed -i -e "s/SIM_MISSED\==[a-z,A-Z]*/SIM_MISSED=TRUE/" ./generics.f
Sample file content in generics.f:
SIM_MULTI=foo
SIM_MISSED=bar
Testing:
$ make all
sed -i -e "s/SIM_MULTI\==[a-z,A-Z]*/SIM_MULTI=TRUE/" ./generics.f
sed -i -e "s/SIM_MISSED\==[a-z,A-Z]*/SIM_MISSED=TRUE/" ./generics.f
Confirmed that both sed commands fail to edit a file with this content.
To fix:
Probably, you need to simply remove the \= from your regular expression. The backslash there has no effect, and causes your regex to simply match two equals signs ==. Thus this works:
all:
sed -i 's/SIM_MULTI=[a-zA-Z]*/SIM_MULTI=TRUE/' ./generics.f
sed -i 's/SIM_MISSED=[a-zA-Z]*/SIM_MISSED=TRUE/' ./generics.f
Testing:
$ make all
sed -i 's/SIM_MULTI=[a-zA-Z]*/SIM_MULTI=TRUE/' ./generics.f
sed -i 's/SIM_MISSED=[a-zA-Z]*/SIM_MISSED=TRUE/' ./generics.f
$ cat generics.f
SIM_MULTI=TRUE
SIM_MISSED=TRUE
Further explanation:
There is no need to specify -e there.
There is no need to enclose the script in double quotes, which is riskier because it allows the contents to be modified by the shell.
The bug appears to be \= and I deleted those characters, as mentioned above.
Note that I removed the comma , as well in [a-z,A-Z]. I think that probably isn't what you meant, and it would cause a class of characters including a-z, A-Z and a comma , to be matched by the regex. (And if it is what you mean, you might consider writing it as [a-zA-Z,] as that would be less confusing.)
If this has not resolved your issue, I would need to know things like:
What is the version of your sed.
What is the contents in generics.f.
POSIX/GNU sed have c for "change":
sed -i '/SIM_MULTI=/c\SIM_MULTI=TRUE'
sed -i '/SIM_MISSED=/c\SIM_MISSED=TRUE'

using sed to replace string with special characters

I'm basically trying to modify tomcat server.xml connector tag and add a address attribute to it.
I want to find the below string in server.xml
I'm doing the below with sed,
export currlistener=\<Connector\ port\=\"18443\"
export newlistener=\<Connector\ port\=\"18443\"\ address\=\"127.0.0.1\"\
echo $currlistener
echo $newlistener
sed -i -e 's/'$currlistener'/'$newlistener'/g' server.xml
But I get the error
sed: -e expression #1, char 12: unterminated `s' command
I guess sed is interpreting the special characters and erroring out.
How would I do the same using awk?
Regards,
Anand.
Using sed
The problem was that the shell variables were unquoted. Try:
sed -i -e "s/$currlistener/$newlistener/g" server.xml
Using awk
The sed solution requires that you trust the source of your shell variables. For a case like this, awk is safer. Using a modern GNU awk:
awk -i inplace -v a="$currlistener" -v b="$newlistener" '{gsub(a, b)} 1' server.xml
Or, using other awk:
awk -v a="$currlistener" -v b="$newlistener" '{gsub(a, b)} 1' server.xml >tmp && mv tmp server.sml
Simplifying the variable assignments
Separately, the shell variables can be defined without requiring so many escapes:
currlistener='<Connector port="18443"'
newlistener='<Connector port="18443" address="127.0.0.1"'
It is only necessary to export them if they are to be used in a child process.

Sed command not working on a different server

Sed command is not replacing the contents, does so on a replicated server. Both are runnin ksh.
sed -i '/NewValue/s/NewValue/SAPROD/g' AVL_5002760241.GMF
This works properly. Replaced all NewValue to SAPROD.
sed -i '/SAPROD.*/s/SAPROD/NewValue/g' AVL_5002760241.GMF
This also works correctly. Replaced all SAPROD to to NewValue
sed -i '/NewValue.*500175852/s/NewValue/SAPROD/g' AVL_5002760241.GMF
This does not do any substitution.
Run this way (LANG=C some command) LANG will only be changed for the sed command, not for the surrounding shell. Works for all environment variables.
(Quoting #Wintermute to make a Q/A pair.)

Specifiying a file in a specific directory in sed

I'm using Sed on a Mac. I am trying to do a simple string replace on a file that is not in the directory. I do:
sed -i 's/old/new/' /Users/A/file
and it says invalid command code A.
What do I need to do?
The -i option in OSX/BSD sed is a little different than the GNU/Linux version in that it requires a backup extension to be given, even if it's an empty string (which means that no backup will be made). The "invalid command code" error message occurs because s/old/new is taken as the backup extension and /Users/A/file is taken as the script (where A is seen as an invalid command name). So it needs to be something like:
sed -i '' 's/old/new/' /Users/A/file
if you have perl:
perl -p -i -e 's/old/new/' /Users/A/file
The -i in sed is not a standard across OS's (not a POSIX standard). This should work every time:
cp /Users/A/file /Users/A/file.sed
cat /Users/A/file.sed | sed 's/old/new' > /Users/A/file