linux/net/wireless/tests/fragmentation.c
Johannes Berg 8ade3356b2 wifi: cfg80211: allow cfg80211_defragment_element() without output
If we just want to determine the length of the fragmented
data, we basically need the same logic, and really we want
it to be _literally_ the same logic, so it cannot be out
of sync in any way.

Allow calling cfg80211_defragment_element() without an output
buffer, where it then just returns the required output size.

Also add this to the tests, just to exercise it, using the
pre-calculated length to really do the defragmentation, which
checks that this is sufficient.

Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Reviewed-by: Benjamin Berg <benjamin.berg@intel.com>
Link: https://msgid.link/20240228095718.6d6565b9e3f2.Ib441903f4b8644ba04b1c766f90580ee6f54fc66@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2024-03-04 14:33:51 +01:00

178 lines
4.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* KUnit tests for element fragmentation
*
* Copyright (C) 2023-2024 Intel Corporation
*/
#include <linux/ieee80211.h>
#include <net/cfg80211.h>
#include <kunit/test.h>
static void defragment_0(struct kunit *test)
{
ssize_t ret;
static const u8 input[] = {
[0] = WLAN_EID_EXTENSION,
[1] = 254,
[2] = WLAN_EID_EXT_EHT_MULTI_LINK,
[27] = 27,
[123] = 123,
[254 + 2] = WLAN_EID_FRAGMENT,
[254 + 3] = 7,
[254 + 3 + 7] = 0, /* for size */
};
u8 *data = kunit_kzalloc(test, sizeof(input), GFP_KERNEL);
KUNIT_ASSERT_NOT_NULL(test, data);
ret = cfg80211_defragment_element((void *)input,
input, sizeof(input),
NULL, 0,
WLAN_EID_FRAGMENT);
KUNIT_EXPECT_EQ(test, ret, 253);
ret = cfg80211_defragment_element((void *)input,
input, sizeof(input),
data, ret,
WLAN_EID_FRAGMENT);
KUNIT_EXPECT_EQ(test, ret, 253);
KUNIT_EXPECT_MEMEQ(test, data, input + 3, 253);
}
static void defragment_1(struct kunit *test)
{
ssize_t ret;
static const u8 input[] = {
[0] = WLAN_EID_EXTENSION,
[1] = 255,
[2] = WLAN_EID_EXT_EHT_MULTI_LINK,
[27] = 27,
[123] = 123,
[255 + 2] = WLAN_EID_FRAGMENT,
[255 + 3] = 7,
[255 + 3 + 1] = 0xaa,
[255 + 3 + 8] = WLAN_EID_FRAGMENT, /* not used */
[255 + 3 + 9] = 1,
[255 + 3 + 10] = 0, /* for size */
};
u8 *data = kunit_kzalloc(test, sizeof(input), GFP_KERNEL);
const struct element *elem;
int count = 0;
KUNIT_ASSERT_NOT_NULL(test, data);
for_each_element(elem, input, sizeof(input))
count++;
/* check the elements are right */
KUNIT_ASSERT_EQ(test, count, 3);
ret = cfg80211_defragment_element((void *)input,
input, sizeof(input),
NULL, 0,
WLAN_EID_FRAGMENT);
KUNIT_EXPECT_EQ(test, ret, 254 + 7);
ret = cfg80211_defragment_element((void *)input,
input, sizeof(input),
data, ret,
WLAN_EID_FRAGMENT);
/* this means the last fragment was not used */
KUNIT_EXPECT_EQ(test, ret, 254 + 7);
KUNIT_EXPECT_MEMEQ(test, data, input + 3, 254);
KUNIT_EXPECT_MEMEQ(test, data + 254, input + 255 + 4, 7);
}
static void defragment_2(struct kunit *test)
{
ssize_t ret;
static const u8 input[] = {
[0] = WLAN_EID_EXTENSION,
[1] = 255,
[2] = WLAN_EID_EXT_EHT_MULTI_LINK,
[27] = 27,
[123] = 123,
[257 + 0] = WLAN_EID_FRAGMENT,
[257 + 1] = 255,
[257 + 20] = 0xaa,
[2 * 257 + 0] = WLAN_EID_FRAGMENT,
[2 * 257 + 1] = 1,
[2 * 257 + 2] = 0xcc,
[2 * 257 + 3] = WLAN_EID_FRAGMENT, /* not used */
[2 * 257 + 4] = 1,
[2 * 257 + 5] = 0, /* for size */
};
u8 *data = kunit_kzalloc(test, sizeof(input), GFP_KERNEL);
const struct element *elem;
int count = 0;
KUNIT_ASSERT_NOT_NULL(test, data);
for_each_element(elem, input, sizeof(input))
count++;
/* check the elements are right */
KUNIT_ASSERT_EQ(test, count, 4);
ret = cfg80211_defragment_element((void *)input,
input, sizeof(input),
NULL, 0,
WLAN_EID_FRAGMENT);
/* this means the last fragment was not used */
KUNIT_EXPECT_EQ(test, ret, 254 + 255 + 1);
ret = cfg80211_defragment_element((void *)input,
input, sizeof(input),
data, ret,
WLAN_EID_FRAGMENT);
KUNIT_EXPECT_EQ(test, ret, 254 + 255 + 1);
KUNIT_EXPECT_MEMEQ(test, data, input + 3, 254);
KUNIT_EXPECT_MEMEQ(test, data + 254, input + 257 + 2, 255);
KUNIT_EXPECT_MEMEQ(test, data + 254 + 255, input + 2 * 257 + 2, 1);
}
static void defragment_at_end(struct kunit *test)
{
ssize_t ret;
static const u8 input[] = {
[0] = WLAN_EID_EXTENSION,
[1] = 255,
[2] = WLAN_EID_EXT_EHT_MULTI_LINK,
[27] = 27,
[123] = 123,
[255 + 2] = WLAN_EID_FRAGMENT,
[255 + 3] = 7,
[255 + 3 + 7] = 0, /* for size */
};
u8 *data = kunit_kzalloc(test, sizeof(input), GFP_KERNEL);
KUNIT_ASSERT_NOT_NULL(test, data);
ret = cfg80211_defragment_element((void *)input,
input, sizeof(input),
NULL, 0,
WLAN_EID_FRAGMENT);
KUNIT_EXPECT_EQ(test, ret, 254 + 7);
ret = cfg80211_defragment_element((void *)input,
input, sizeof(input),
data, ret,
WLAN_EID_FRAGMENT);
KUNIT_EXPECT_EQ(test, ret, 254 + 7);
KUNIT_EXPECT_MEMEQ(test, data, input + 3, 254);
KUNIT_EXPECT_MEMEQ(test, data + 254, input + 255 + 4, 7);
}
static struct kunit_case element_fragmentation_test_cases[] = {
KUNIT_CASE(defragment_0),
KUNIT_CASE(defragment_1),
KUNIT_CASE(defragment_2),
KUNIT_CASE(defragment_at_end),
{}
};
static struct kunit_suite element_fragmentation = {
.name = "cfg80211-element-defragmentation",
.test_cases = element_fragmentation_test_cases,
};
kunit_test_suite(element_fragmentation);