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# So that this file can also be read with `.' or `source' ...
compaudit() { # Define and then call
# Audit the fpath to assure that it contains all the directories needed by
# the completion system, and that those directories are at least unlikely
# to contain dangerous files. This is far from perfect, as the modes or
# ownership of files or directories might change between the time of the
# audit and the time the function is executed.
# This function is designed to be called from compinit, which assumes that
# it is in the same directory, i.e., it can be autoloaded from the initial
# fpath as compinit was. Most local parameter names in this function must
# therefore be the same as those used in compinit.
emulate -L zsh
setopt extendedglob
[[ -x /usr/bin/getent ]] || getent() {
if [[ $2 = <-> ]]; then
grep ":$2:[^:]*$" /etc/$1
else
grep "^$2:" /etc/$1
fi
}
# The positional parameters are the directories to check, else fpath.
if (( $# )); then
local _compdir=''
elif (( $#fpath == 0 )); then
print 'compaudit: No directories in $fpath, cannot continue' 1>&2
return 1
else
set -- $fpath
fi
# _i_check is defined by compinit; used here as a test for whether this
# function is running standalone or was called by compinit. If called
# by compinit, we use parameters that are defined in compinit's scope,
# otherwise we make them local here.
(( $+_i_check )) || {
local _i_q _i_line _i_file _i_fail=verbose
local -a _i_files _i_addfiles _i_wdirs _i_wfiles
local -a -U +h fpath
}
fpath=( $* )
# _compdir may be defined by the user; see the compinit documentation.
# If it isn't defined, we want it to point somewhere sensible, but the
# user is allowed to set it to empty to bypass the check below.
(( $+_compdir )) || {
local _compdir=${fpath[(r)*/$ZSH_VERSION/*]}
[[ -z $_compdir ]] && _compdir=$fpath[1]
### [[ -d $_compdir/../Base ]] && _compdir=${_compdir:h}
}
_i_wdirs=()
_i_wfiles=()
_i_files=( ${^~fpath:/.}/^([^_]*|*~|*.zwc)(N) )
if [[ -n $_compdir ]]; then
if [[ $#_i_files -lt 20 || $_compdir = */Base || -d $_compdir/Base ]]; then
# Too few files: we need some more directories, or we need to check
# that all directories (not just Base) are present.
_i_addfiles=()
if [[ -d $_compdir/Base/Core ]]; then
# Add all the Completion subdirectories (CVS-layout)
_i_addfiles=(${_compdir}/*/*(/^M))
elif [[ -d $_compdir/Base ]]; then
# Likewise (installation-layout)
_i_addfiles=(${_compdir}/*(/^M))
fi
for _i_line in {1..$#_i_addfiles}; do
_i_file=${_i_addfiles[$_i_line]}
[[ -d $_i_file && -z ${fpath[(r)$_i_file]} ]] ||
_i_addfiles[$_i_line]=
done
fpath=($fpath $_i_addfiles)
_i_files=( ${^~fpath:/.}/^([^_]*|*~|*.zwc)(N) )
fi
fi
[[ $_i_fail == use ]] && return 0
# We will always allow files to be owned by root and the owner of the
# present process.
local _i_owners="u0u${EUID}"
# Places we will look for a link to the executable
local -a _i_exes
_i_exes=(
/proc/$$/exe
/proc/$$/object/a.out
)
local _i_exe
# If we can find out who owns the executable, we will allow files to
# be owned by that user, too. The argument is that if you don't trust
# the owner of the executable, it's way too late to worry about it now...
for _i_exe in $_i_exes; do
if [[ -e $_i_exe ]] ;then
if zmodload -F zsh/stat b:zstat 2>/dev/null; then
local -A _i_stathash
if zstat -H _i_stathash $_i_exe &&
[[ $_i_stathash[uid] -ne 0 ]]; then
_i_owners+="u${_i_stathash[uid]}"
fi
fi
break
fi
done
# We search for:
# - world/group-writable directories in fpath not owned by $_i_owners
# - parent-directories of directories in fpath that are world/group-writable
# and not owned by $_i_owners (that would allow someone to put a
# digest file for one of the directories into the parent directory)
# - digest files for one of the directories in fpath not owned by $_i_owners
# - and for files in directories from fpath not owned by $_i_owners
# (including zwc files)
_i_wdirs=( ${^fpath}(N-f:g+w:,-f:o+w:,-^${_i_owners})
${^fpath:h}(N-f:g+w:,-f:o+w:,-^${_i_owners}) )
# RedHat Linux "per-user groups" check. This is tricky, because it's very
# difficult to tell whether the sysadmin has put someone else into your
# "private" group (e.g., via the default group field in /etc/passwd, or
# by NFS group sharing with an untrustworthy machine). So we must assume
# that this has not happened, and pick the best group.
if (( $#_i_wdirs )); then
local GROUP GROUPMEM _i_pw _i_gid
if ((UID == EUID )); then
getent group $LOGNAME | IFS=: read GROUP _i_pw _i_gid GROUPMEM
else
getent group $EGID | IFS=: read GROUP _i_pw _i_gid GROUPMEM
fi
if [[ $GROUP == $LOGNAME && ( -z $GROUPMEM || $GROUPMEM == $LOGNAME ) ]]
then
_i_wdirs=( ${^_i_wdirs}(N-f:g+w:^g:${GROUP}:,-f:o+w:,-^${_i_owners}) )
fi
fi
if [[ -f /etc/debian_version ]]
then
local _i_ulwdirs
_i_ulwdirs=( ${(M)_i_wdirs:#/usr/local/*} )
_i_wdirs=( ${_i_wdirs:#/usr/local/*} ${^_i_ulwdirs}(Nf:g+ws:^g:staff:,f:o+w:,^u0) )
fi
_i_wdirs=( $_i_wdirs ${^fpath}.zwc^([^_]*|*~)(N-^${_i_owners}) )
_i_wfiles=( ${^fpath}/^([^_]*|*~)(N-^${_i_owners}) )
case "${#_i_wdirs}:${#_i_wfiles}" in
(0:0) _i_q= ;;
(0:*) _i_q=files ;;
(*:0) _i_q=directories ;;
(*:*) _i_q='directories and files' ;;
esac
if [[ -n "$_i_q" ]]; then
[[ $_i_fail == verbose ]] && {
print There are insecure ${_i_q}: 1>&2
print -l - $_i_wdirs $_i_wfiles
}
return 1
fi
return 0
} # Define and then call
compaudit "$@"
|
