/usr/include/php5/ext/hash/ is in php5-dev 5.3.10-1ubuntu3.26.
This file is owned by root:root, with mode 0o755.
..
/usr/include/php5/ext/hash/php_hash.h
/usr/include/php5/ext/hash/php_hash_adler32.h
/usr/include/php5/ext/hash/php_hash_crc32.h
/usr/include/php5/ext/hash/php_hash_gost.h
/usr/include/php5/ext/hash/php_hash_haval.h
/usr/include/php5/ext/hash/php_hash_md.h
/usr/include/php5/ext/hash/php_hash_ripemd.h
/usr/include/php5/ext/hash/php_hash_salsa.h
/usr/include/php5/ext/hash/php_hash_sha.h
/usr/include/php5/ext/hash/php_hash_snefru.h
/usr/include/php5/ext/hash/php_hash_tiger.h
/usr/include/php5/ext/hash/php_hash_types.h
/usr/include/php5/ext/hash/php_hash_whirlpool.h