def crypto_pwhash_scryptsalsa208sha256_ll(passwd,
salt,
n,
r,
p,
dklen=64,
maxmem=SCRYPT_MAX_MEM):
"""
Derive a cryptographic key using the ``passwd`` and ``salt``
given as input.
The work factor can be tuned by by picking different
values for the parameters
:param bytes passwd:
:param bytes salt:
:param bytes salt: *must* be *exactly* :py:const:`.SALTBYTES` long
:param int dklen:
:param int opslimit:
:param int n:
:param int r: block size,
:param int p: the parallelism factor
:param int maxmem: the maximum available memory available for scrypt's
operations
:rtype: bytes
:raises nacl.exceptions.UnavailableError: If called when using a
minimal build of libsodium.
"""
ensure(
has_crypto_pwhash_scryptsalsa208sha256,
"Not available in minimal build",
raising=exc.UnavailableError,
)
ensure(isinstance(n, int), raising=TypeError)
ensure(isinstance(r, int), raising=TypeError)
ensure(isinstance(p, int), raising=TypeError)
ensure(isinstance(passwd, bytes), raising=TypeError)
ensure(isinstance(salt, bytes), raising=TypeError)
_check_memory_occupation(n, r, p, maxmem)
buf = ffi.new("uint8_t[]", dklen)
ret = lib.crypto_pwhash_scryptsalsa208sha256_ll(passwd, len(passwd), salt,
len(salt), n, r, p, buf,
dklen)
ensure(
ret == 0,
"Unexpected failure in key derivation",
raising=exc.RuntimeError,
)
return ffi.buffer(ffi.cast("char *", buf), dklen)[:]
def crypto_pwhash_scryptsalsa208sha256_ll(passwd, salt, n, r, p, dklen=64,
maxmem=SCRYPT_MAX_MEM):
"""
Derive a cryptographic key using the ``passwd`` and ``salt``
given as input.
The work factor can be tuned by by picking different
values for the parameters
:param bytes passwd:
:param bytes salt:
:param bytes salt: *must* be *exactly* :py:const:`.SALTBYTES` long
:param int dklen:
:param int opslimit:
:param int n:
:param int r: block size,
:param int p: the parallelism factor
:param int maxmem: the maximum available memory available for scrypt's
operations
:rtype: bytes
"""
ensure(isinstance(n, int),
raising=TypeError)
ensure(isinstance(r, int),
raising=TypeError)
ensure(isinstance(p, int),
raising=TypeError)
ensure(isinstance(passwd, bytes),
raising=TypeError)
ensure(isinstance(salt, bytes),
raising=TypeError)
_check_memory_occupation(n, r, p, maxmem)
buf = ffi.new("uint8_t[]", dklen)
ret = lib.crypto_pwhash_scryptsalsa208sha256_ll(passwd, len(passwd),
salt, len(salt),
n, r, p,
buf, dklen)
ensure(ret == 0, 'Unexpected failure in key derivation',
raising=exc.RuntimeError)
return ffi.buffer(ffi.cast("char *", buf), dklen)[:]