diff options
Diffstat (limited to 'Objects/object.c')
| -rw-r--r-- | Objects/object.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/Objects/object.c b/Objects/object.c index 8134825..bb18d47 100644 --- a/Objects/object.c +++ b/Objects/object.c @@ -759,10 +759,19 @@ _Py_HashBytes(unsigned char *p, Py_ssize_t len) Py_uhash_t x; Py_ssize_t i; - x = (Py_uhash_t) *p << 7; + /* + We make the hash of the empty string be 0, rather than using + (prefix ^ suffix), since this slightly obfuscates the hash secret + */ + if (len == 0) { + return 0; + } + x = (Py_uhash_t) _Py_HashSecret.prefix; + x ^= (Py_uhash_t) *p << 7; for (i = 0; i < len; i++) x = (_PyHASH_MULTIPLIER * x) ^ (Py_uhash_t) *p++; x ^= (Py_uhash_t) len; + x ^= (Py_uhash_t) _Py_HashSecret.suffix; if (x == -1) x = -2; return x; @@ -776,6 +785,8 @@ PyObject_HashNotImplemented(PyObject *v) return -1; } +_Py_HashSecret_t _Py_HashSecret; + Py_hash_t PyObject_Hash(PyObject *v) { |