crypto: ccree - fix some reported cipher block sizes

OFB and CTR modes block sizes were wrongfully reported as
the underlying block sizes. Fix it to 1 bytes as they
turn the block ciphers into stream ciphers.

Also document why our XTS differes from the generic
implementation.

Signed-off-by: Gilad Ben-Yossef <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>

Author: Gilad Ben-Yossef

drivers/crypto/ccree/cc_cipher.c

@@ -1228,6 +1228,10 @@ static const struct cc_alg_template skcipher_algs[] = {
 		.sec_func = true,
 	},
 	{
+		/* See https://www.mail-archive.com/[email protected]/msg40576.html
+		 * for the reason why this differs from the generic
+		 * implementation.
+		 */
 		.name = "xts(aes)",
 		.driver_name = "xts-aes-ccree",
 		.blocksize = 1,
@@ -1423,7 +1427,7 @@ static const struct cc_alg_template skcipher_algs[] = {
 	{
 		.name = "ofb(aes)",
 		.driver_name = "ofb-aes-ccree",
-		.blocksize = AES_BLOCK_SIZE,
+		.blocksize = 1,
 		.template_skcipher = {
 			.setkey = cc_cipher_setkey,
 			.encrypt = cc_cipher_encrypt,
@@ -1576,7 +1580,7 @@ static const struct cc_alg_template skcipher_algs[] = {
 	{
 		.name = "ctr(sm4)",
 		.driver_name = "ctr-sm4-ccree",
-		.blocksize = SM4_BLOCK_SIZE,
+		.blocksize = 1,
 		.template_skcipher = {
 			.setkey = cc_cipher_setkey,
 			.encrypt = cc_cipher_encrypt,