aboutsummaryrefslogtreecommitdiff
path: root/v_windows/v/old/vlib/crypto/internal/subtle
diff options
context:
space:
mode:
authorIndrajith K L2022-12-03 17:00:20 +0530
committerIndrajith K L2022-12-03 17:00:20 +0530
commitf5c4671bfbad96bf346bd7e9a21fc4317b4959df (patch)
tree2764fc62da58f2ba8da7ed341643fc359873142f /v_windows/v/old/vlib/crypto/internal/subtle
downloadcli-tools-windows-master.tar.gz
cli-tools-windows-master.tar.bz2
cli-tools-windows-master.zip
Adds most of the toolsHEADmaster
Diffstat (limited to 'v_windows/v/old/vlib/crypto/internal/subtle')
-rw-r--r--v_windows/v/old/vlib/crypto/internal/subtle/aliasing.v29
-rw-r--r--v_windows/v/old/vlib/crypto/internal/subtle/comparison.v53
-rw-r--r--v_windows/v/old/vlib/crypto/internal/subtle/comparison_test.v65
3 files changed, 147 insertions, 0 deletions
diff --git a/v_windows/v/old/vlib/crypto/internal/subtle/aliasing.v b/v_windows/v/old/vlib/crypto/internal/subtle/aliasing.v
new file mode 100644
index 0000000..e09748e
--- /dev/null
+++ b/v_windows/v/old/vlib/crypto/internal/subtle/aliasing.v
@@ -0,0 +1,29 @@
+// Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+// Package subtle implements functions that are often useful in cryptographic
+// code but require careful thought to use correctly.
+module subtle
+
+// NOTE: require unsafe in future
+// any_overlap reports whether x and y share memory at any (not necessarily
+// corresponding) index. The memory beyond the slice length is ignored.
+pub fn any_overlap(x []byte, y []byte) bool {
+ // NOTE: Remember to come back to this (joe-c)
+ return x.len > 0 && y.len > 0 && // &x.data[0] <= &y.data[y.len-1] &&
+ // &y.data[0] <= &x.data[x.len-1]
+ unsafe { &x[0] <= &y[y.len - 1] && &y[0] <= &x[x.len - 1] }
+}
+
+// inexact_overlap reports whether x and y share memory at any non-corresponding
+// index. The memory beyond the slice length is ignored. Note that x and y can
+// have different lengths and still not have any inexact overlap.
+//
+// inexact_overlap can be used to implement the requirements of the crypto/cipher
+// AEAD, Block, BlockMode and Stream interfaces.
+pub fn inexact_overlap(x []byte, y []byte) bool {
+ if x.len == 0 || y.len == 0 || unsafe { &x[0] == &y[0] } {
+ return false
+ }
+ return any_overlap(x, y)
+}
diff --git a/v_windows/v/old/vlib/crypto/internal/subtle/comparison.v b/v_windows/v/old/vlib/crypto/internal/subtle/comparison.v
new file mode 100644
index 0000000..e7dd162
--- /dev/null
+++ b/v_windows/v/old/vlib/crypto/internal/subtle/comparison.v
@@ -0,0 +1,53 @@
+module subtle
+
+// constant_time_byte_eq returns 1 when x == y.
+pub fn constant_time_byte_eq(x byte, y byte) int {
+ return int((u32(x ^ y) - 1) >> 31)
+}
+
+// constant_time_eq returns 1 when x == y.
+pub fn constant_time_eq(x int, y int) int {
+ return int((u64(u32(x ^ y)) - 1) >> 63)
+}
+
+// constant_time_select returns x when v == 1, and y when v == 0.
+// it is undefined when v is any other value
+pub fn constant_time_select(v int, x int, y int) int {
+ return (~(v - 1) & x) | ((v - 1) & y)
+}
+
+// constant_time_compare returns 1 when x and y have equal contents.
+// The runtime of this function is proportional of the length of x and y.
+// It is *NOT* dependent on their content.
+pub fn constant_time_compare(x []byte, y []byte) int {
+ if x.len != y.len {
+ return 0
+ }
+ mut v := byte(0)
+ for i in 0 .. x.len {
+ v |= x[i] ^ y[i]
+ }
+ return constant_time_byte_eq(v, 0)
+}
+
+// constant_time_copy copies the contents of y into x, when v == 1.
+// When v == 0, x is left unchanged. this function is undefined, when
+// v takes any other value
+pub fn constant_time_copy(v int, mut x []byte, y []byte) {
+ if x.len != y.len {
+ panic('subtle: arrays have different lengths')
+ }
+ xmask := byte(v - 1)
+ ymask := byte(~(v - 1))
+ for i := 0; i < x.len; i++ {
+ x[i] = x[i] & xmask | y[i] & ymask
+ }
+}
+
+// constant_time_less_or_eq returns 1 if x <= y, and 0 otherwise.
+// it is undefined when x or y are negative, or > (2^32 - 1)
+pub fn constant_time_less_or_eq(x int, y int) int {
+ x32 := int(x)
+ y32 := int(y)
+ return int(((x32 - y32 - 1) >> 31) & 1)
+}
diff --git a/v_windows/v/old/vlib/crypto/internal/subtle/comparison_test.v b/v_windows/v/old/vlib/crypto/internal/subtle/comparison_test.v
new file mode 100644
index 0000000..b339746
--- /dev/null
+++ b/v_windows/v/old/vlib/crypto/internal/subtle/comparison_test.v
@@ -0,0 +1,65 @@
+module subtle
+
+fn test_constant_time_byte_eq() {
+ assert constant_time_byte_eq(0, 0) == 1
+ assert constant_time_byte_eq(1, 1) == 1
+ assert constant_time_byte_eq(255, 255) == 1
+ assert constant_time_byte_eq(255, 1) == 0
+ assert constant_time_byte_eq(1, 255) == 0
+ assert constant_time_byte_eq(2, 1) == 0
+}
+
+fn test_constant_time_eq() {
+ assert constant_time_eq(0, 0) == 1
+ assert constant_time_eq(255, 255) == 1
+ assert constant_time_eq(65536, 65536) == 1
+ assert constant_time_eq(-1, -1) == 1
+ assert constant_time_eq(-256, -256) == 1
+ assert constant_time_eq(0, 1) == 0
+}
+
+fn test_constant_time_select() {
+ assert constant_time_select(1, 1, 0) == 1
+ assert constant_time_select(1, 1, 255) == 1
+ assert constant_time_select(1, 1, 255 * 255) == 1
+ assert constant_time_select(1, 2, 0) == 2
+ assert constant_time_select(1, 2, 255) == 2
+ assert constant_time_select(1, 2, 255 * 255) == 2
+ //
+ assert constant_time_select(0, 1, 0) == 0
+ assert constant_time_select(0, 1, 255) == 255
+ assert constant_time_select(0, 1, 255 * 255) == 255 * 255
+ assert constant_time_select(0, 2, 0) == 0
+ assert constant_time_select(0, 2, 255) == 255
+ assert constant_time_select(0, 2, 255 * 255) == 255 * 255
+}
+
+fn test_constant_time_compare() {
+ assert constant_time_compare([byte(1), 2, 3], [byte(1), 2, 3]) == 1
+ assert constant_time_compare([byte(1), 2, 3], [byte(1), 2, 9]) == 0
+ assert constant_time_compare([byte(1), 2, 3], [byte(1), 2, 3, 4]) == 0
+ assert constant_time_compare([byte(1), 2, 3], [byte(1), 2]) == 0
+}
+
+fn test_constant_time_copy() {
+ y := [byte(3), 4, 5]
+ mut x := [byte(0), 0, 0]
+ constant_time_copy(0, mut x, y)
+ assert x == [byte(0), 0, 0]
+ constant_time_copy(1, mut x, y)
+ assert x == y
+ assert x == [byte(3), 4, 5]
+}
+
+fn test_constant_time_less_or_eq() {
+ assert constant_time_less_or_eq(1, 1) == 1
+ assert constant_time_less_or_eq(1, 2) == 1
+ assert constant_time_less_or_eq(1, 3) == 1
+ assert constant_time_less_or_eq(255, 255) == 1
+ assert constant_time_less_or_eq(255, 256) == 1
+ assert constant_time_less_or_eq(255, 257) == 1
+ assert constant_time_less_or_eq(1, 0) == 0
+ assert constant_time_less_or_eq(2, 1) == 0
+ assert constant_time_less_or_eq(3, 2) == 0
+ assert constant_time_less_or_eq(255, 3) == 0
+}