kumquat-buildroot/support/download/check-hash

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#!/usr/bin/env bash
set -e
# Helper to check a file matches its known hash
# Call it with:
# $1: the path of the file containing all the the expected hashes
# $2: the full path to the temporary file that was downloaded, and
# that is to be checked
# $3: the final basename of the file, to which it will be ultimately
# saved as, to be able to match it to the corresponding hashes
# in the .hash file
while getopts :q OPT; do
case "${OPT}" in
q) exec >/dev/null;;
\?) exit 1;;
esac
done
shift $((OPTIND-1))
h_file="${1}"
file="${2}"
base="${3}"
# Does the hash-file exist?
if [ ! -f "${h_file}" ]; then
exit 0
fi
# Check one hash for a file
# $1: known hash
# $2: file (full path)
check_one_hash() {
_h="${1}"
_known="${2}"
_file="${3}"
# Note: md5 is supported, but undocumented on purpose.
# Note: sha3 is not supported, since there is currently no implementation
# (the NIST has yet to publish the parameters).
case "${_h}" in
md5|sha1) ;;
sha224|sha256|sha384|sha512) ;;
*) # Unknown hash, exit with error
printf "ERROR: unknown hash '%s' for '%s'\n" \
"${_h}" "${base}" >&2
exit 1
;;
esac
# Do the hashes match?
_hash=$( ${_h}sum "${_file}" |cut -d ' ' -f 1 )
if [ "${_hash}" = "${_known}" ]; then
printf "%s: OK (%s: %s)\n" "${base}" "${_h}" "${_hash}"
return 0
fi
printf "ERROR: %s has wrong %s hash:\n" "${base}" "${_h}" >&2
printf "ERROR: expected: %s\n" "${_known}" >&2
printf "ERROR: got : %s\n" "${_hash}" >&2
printf "ERROR: Incomplete download, or man-in-the-middle (MITM) attack\n" >&2
exit 1
}
# Do we know one or more hashes for that file?
nb_checks=0
while read t h f; do
case "${t}" in
''|'#'*)
# Skip comments and empty lines
continue
;;
*)
if [ "${f}" = "${base}" ]; then
check_one_hash "${t}" "${h}" "${file}"
: $((nb_checks++))
fi
;;
esac
done <"${h_file}"
if [ ${nb_checks} -eq 0 ]; then
if [ -n "${BR2_ENFORCE_CHECK_HASH}" ]; then
printf "ERROR: No hash found for %s\n" "${base}" >&2
exit 1
else
printf "WARNING: No hash found for %s\n" "${base}" >&2
fi
fi