>but could you please help me in writing a script? I will be grateful, if you could give me some basic idea to begin with at least.
With UNIX, you can break up the task with multiple scripts. As you feel more confident you can put them together.
Here are two scripts that will generate chown commands:
=================
chown_script_A.sh:
#!/usr/bin/ksh
# Use find to generate a list of files. Then build up chown for each
# file.
# Only do current filesystem
# Usage: list-of-directories
find $* -xdev -exec \ll -d {} +
=================
chown_script_B.sh:
#!/usr/bin/ksh
# Read stdin for a list of ll(1) output. Generate chown commands
# Use chown -h, since it works on symlinks and files/directories.
# Usage: ... | $0
# Usage: $0 < file
awk '
{
print "chown -h", $3 ":" $4, $9
} '
===============================
You would execute this on your good system:
chown_script_A.sh /etc | chown_script_B.sh > chown.sh
If you are happy with the contents, copy to your bad system as execute it as follows:
# sh chown.sh
Doing the chmod is harder since symlinks must be skipped and handling of SUID and sticky bits.
Here is my first pass at that script:
=================
chmod_script_C.sh:
#!/usr/bin/ksh
# Read stdin for a list of ll(1) output. Generate chmod commands
# Usage: ... | $0
# Usage: $0 < file
awk '
{
type = substr($1, 1, 1)
if (type == "l") {
print "# Symlink skipped:", $1, $9
next
}
user = substr($1, 2, 3)
group = substr($1, 5, 3)
other = substr($1, 8, 3)
# remove "-"
gsub("-", "", user)
gsub("-", "", group)
gsub("-", "", other)
# handle SUID and sticky bits
sub("s", "sx", user)
sub("S", "s", user)
sub("s", "sx", group)
sub("S", "s", group)
sub("t", "tx", other)
sub("T", "t", other)
print "chmod u=" user ",g=" group ",o=" other, $9
} '
===============================
You would execute this on your good system:
chown_script_A.sh /etc | chmod_script_C.sh > chmod.sh
If you are happy with the contents, copy to your bad system as execute it as follows:
# sh chmod.sh
