2013-10-30 10:51:51

by Daniel Borkmann

[permalink] [raw]
Subject: [PATCH net-next 3/5] lib: crc32: add test cases for crc32{,c}_combine routines

We already have 100 test cases for crcs itself, so split the test
buffer with a-prio known checksums, and test crc of two blocks
against crc of the whole block for the same results.

Output/result with CONFIG_CRC32_SELFTEST=y:

[ 2.687095] crc32: CRC_LE_BITS = 64, CRC_BE BITS = 64
[ 2.687097] crc32: self tests passed, processed 225944 bytes in 278177 nsec
[ 2.687383] crc32c: CRC_LE_BITS = 64
[ 2.687385] crc32c: self tests passed, processed 225944 bytes in 141708 nsec
[ 7.336771] crc32_combine: 113072 self tests passed
[ 12.050479] crc32c_combine: 113072 self tests passed
[ 17.633089] alg: No test for crc32 (crc32-pclmul)

Signed-off-by: Daniel Borkmann <[email protected]>
Cc: [email protected]
---
lib/crc32.c | 72 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 72 insertions(+)

diff --git a/lib/crc32.c b/lib/crc32.c
index 595205c..69dd124 100644
--- a/lib/crc32.c
+++ b/lib/crc32.c
@@ -1031,6 +1031,40 @@ static int __init crc32c_test(void)
return 0;
}

+static int __init crc32c_combine_test(void)
+{
+ int i, j;
+ int errors = 0, runs = 0;
+
+ for (i = 0; i < 100; i++) {
+ u32 crc_full;
+
+ crc_full = __crc32c_le(test[i].crc, test_buf + test[i].start,
+ test[i].length);
+ for (j = 0; j <= test[i].length; ++j) {
+ u32 crc1, crc2;
+ u32 len1 = j, len2 = test[i].length - j;
+
+ crc1 = __crc32c_le(test[i].crc, test_buf +
+ test[i].start, len1);
+ crc2 = __crc32c_le(0, test_buf + test[i].start +
+ len1, len2);
+
+ if (!(crc_full == __crc32c_le_combine(crc1, crc2, len2) &&
+ crc_full == test[i].crc32c_le))
+ errors++;
+ runs++;
+ }
+ }
+
+ if (errors)
+ pr_warn("crc32c_combine: %d/%d self tests failed\n", errors, runs);
+ else
+ pr_info("crc32c_combine: %d self tests passed\n", runs);
+
+ return 0;
+}
+
static int __init crc32_test(void)
{
int i;
@@ -1090,10 +1124,48 @@ static int __init crc32_test(void)
return 0;
}

+static int __init crc32_combine_test(void)
+{
+ int i, j;
+ int errors = 0, runs = 0;
+
+ for (i = 0; i < 100; i++) {
+ u32 crc_full;
+
+ crc_full = crc32_le(test[i].crc, test_buf + test[i].start,
+ test[i].length);
+ for (j = 0; j <= test[i].length; ++j) {
+ u32 crc1, crc2;
+ u32 len1 = j, len2 = test[i].length - j;
+
+ crc1 = crc32_le(test[i].crc, test_buf +
+ test[i].start, len1);
+ crc2 = crc32_le(0, test_buf + test[i].start +
+ len1, len2);
+
+ if (!(crc_full == crc32_le_combine(crc1, crc2, len2) &&
+ crc_full == test[i].crc_le))
+ errors++;
+ runs++;
+ }
+ }
+
+ if (errors)
+ pr_warn("crc32_combine: %d/%d self tests failed\n", errors, runs);
+ else
+ pr_info("crc32_combine: %d self tests passed\n", runs);
+
+ return 0;
+}
+
static int __init crc32test_init(void)
{
crc32_test();
crc32c_test();
+
+ crc32_combine_test();
+ crc32c_combine_test();
+
return 0;
}

--
1.8.3.1