crypto: testmgr - Fix wrong test case of RSA

[ Upstream commit a9887010ed ]

According to the BER encoding rules, integer value should be encoded
as two's complement, and if the highest bit of a positive integer
is 1, should add a leading zero-octet.

The kernel's built-in RSA algorithm cannot recognize negative numbers
when parsing keys, so it can pass this test case.

Export the key to file and run the following command to verify the
fix result:

  openssl asn1parse -inform DER -in /path/to/key/file

Signed-off-by: Lei He <helei.sig11@bytedance.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>

crypto/testmgr.h

@@ -257,9 +257,9 @@ static const struct akcipher_testvec rsa_tv_template[] = {
 	}, {
 #endif
 	.key =
-	"\x30\x82\x02\x1F" /* sequence of 543 bytes */
+	"\x30\x82\x02\x20" /* sequence of 544 bytes */
 	"\x02\x01\x01" /* version - integer of 1 byte */
-	"\x02\x82\x01\x00" /* modulus - integer of 256 bytes */
+	"\x02\x82\x01\x01\x00" /* modulus - integer of 256 bytes */
 	"\xDB\x10\x1A\xC2\xA3\xF1\xDC\xFF\x13\x6B\xED\x44\xDF\xF0\x02\x6D"
 	"\x13\xC7\x88\xDA\x70\x6B\x54\xF1\xE8\x27\xDC\xC3\x0F\x99\x6A\xFA"
 	"\xC6\x67\xFF\x1D\x1E\x3C\x1D\xC1\xB5\x5F\x6C\xC0\xB2\x07\x3A\x6D"
@@ -299,7 +299,7 @@ static const struct akcipher_testvec rsa_tv_template[] = {
 	"\x02\x01\x00" /* exponent1 - integer of 1 byte */
 	"\x02\x01\x00" /* exponent2 - integer of 1 byte */
 	"\x02\x01\x00", /* coefficient - integer of 1 byte */
-	.key_len = 547,
+	.key_len = 548,
 	.m = "\x54\x85\x9b\x34\x2c\x49\xea\x2a",
 	.c =
 	"\xb2\x97\x76\xb4\xae\x3e\x38\x3c\x7e\x64\x1f\xcc\xa2\x7f\xf6\xbe"