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-rw-r--r--frozen_deps/Cryptodome/Util/strxor.py51
1 files changed, 30 insertions, 21 deletions
diff --git a/frozen_deps/Cryptodome/Util/strxor.py b/frozen_deps/Cryptodome/Util/strxor.py
index 91fb4c9..6b16155 100644
--- a/frozen_deps/Cryptodome/Util/strxor.py
+++ b/frozen_deps/Cryptodome/Util/strxor.py
@@ -32,7 +32,8 @@ from Cryptodome.Util._raw_api import (load_pycryptodome_raw_lib, c_size_t,
create_string_buffer, get_raw_buffer,
c_uint8_ptr, is_writeable_buffer)
-_raw_strxor = load_pycryptodome_raw_lib("Cryptodome.Util._strxor",
+_raw_strxor = load_pycryptodome_raw_lib(
+ "Cryptodome.Util._strxor",
"""
void strxor(const uint8_t *in1,
const uint8_t *in2,
@@ -45,33 +46,38 @@ _raw_strxor = load_pycryptodome_raw_lib("Cryptodome.Util._strxor",
def strxor(term1, term2, output=None):
- """XOR two byte strings.
-
+ """From two byte strings of equal length,
+ create a third one which is the byte-by-byte XOR of the two.
+
Args:
term1 (bytes/bytearray/memoryview):
- The first term of the XOR operation.
+ The first byte string to XOR.
term2 (bytes/bytearray/memoryview):
- The second term of the XOR operation.
+ The second byte string to XOR.
output (bytearray/memoryview):
- The location where the result must be written to.
+ The location where the result will be written to.
+ It must have the same length as ``term1`` and ``term2``.
If ``None``, the result is returned.
:Return:
- If ``output`` is ``None``, a new ``bytes`` string with the result.
+ If ``output`` is ``None``, a new byte string with the result.
Otherwise ``None``.
+
+ .. note::
+ ``term1`` and ``term2`` must have the same length.
"""
if len(term1) != len(term2):
raise ValueError("Only byte strings of equal length can be xored")
-
+
if output is None:
result = create_string_buffer(len(term1))
else:
# Note: output may overlap with either input
result = output
-
+
if not is_writeable_buffer(output):
raise TypeError("output must be a bytearray or a writeable memoryview")
-
+
if len(term1) != len(output):
raise ValueError("output must have the same length as the input"
" (%d bytes)" % len(term1))
@@ -88,15 +94,19 @@ def strxor(term1, term2, output=None):
def strxor_c(term, c, output=None):
- """XOR a byte string with a repeated sequence of characters.
+ """From a byte string, create a second one of equal length
+ where each byte is XOR-red with the same value.
Args:
- term(bytes/bytearray/memoryview):
- The first term of the XOR operation.
- c (bytes):
- The byte that makes up the second term of the XOR operation.
- output (None or bytearray/memoryview):
- If not ``None``, the location where the result is stored into.
+ term(bytes/bytearray/memoryview):
+ The byte string to XOR.
+ c (int):
+ Every byte in the string will be XOR-ed with this value.
+ It must be between 0 and 255 (included).
+ output (None or bytearray/memoryview):
+ The location where the result will be written to.
+ It must have the same length as ``term``.
+ If ``None``, the result is returned.
Return:
If ``output`` is ``None``, a new ``bytes`` string with the result.
@@ -105,16 +115,16 @@ def strxor_c(term, c, output=None):
if not 0 <= c < 256:
raise ValueError("c must be in range(256)")
-
+
if output is None:
result = create_string_buffer(len(term))
else:
# Note: output may overlap with either input
result = output
-
+
if not is_writeable_buffer(output):
raise TypeError("output must be a bytearray or a writeable memoryview")
-
+
if len(term) != len(output):
raise ValueError("output must have the same length as the input"
" (%d bytes)" % len(term))
@@ -134,4 +144,3 @@ def strxor_c(term, c, output=None):
def _strxor_direct(term1, term2, result):
"""Very fast XOR - check conditions!"""
_raw_strxor.strxor(term1, term2, result, c_size_t(len(term1)))
-