crypto: inside-secure - Added AES-OFB support

This patch adds support for AES in output feedback mode (AES-OFB).
Signed-off-by: Pascal van Leeuwen <pvanleeuwen@verimatrix.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/inside-secure/safexcel.c

@@ -982,6 +982,7 @@ static struct safexcel_alg_template *safexcel_algs[] = {
 	&safexcel_alg_ecb_aes,
 	&safexcel_alg_cbc_aes,
 	&safexcel_alg_cfb_aes,
+	&safexcel_alg_ofb_aes,
 	&safexcel_alg_ctr_aes,
 	&safexcel_alg_md5,
 	&safexcel_alg_sha1,

drivers/crypto/inside-secure/safexcel.h

@@ -336,6 +336,7 @@ struct safexcel_context_record {
 /* control1 */
 #define CONTEXT_CONTROL_CRYPTO_MODE_ECB		(0 << 0)
 #define CONTEXT_CONTROL_CRYPTO_MODE_CBC		(1 << 0)
+#define CONTEXT_CONTROL_CRYPTO_MODE_OFB		(4 << 0)
 #define CONTEXT_CONTROL_CRYPTO_MODE_CFB		(5 << 0)
 #define CONTEXT_CONTROL_CRYPTO_MODE_CTR_LOAD	(6 << 0)
 #define CONTEXT_CONTROL_CRYPTO_MODE_XTS		(7 << 0)
@@ -769,6 +770,7 @@ extern struct safexcel_alg_template safexcel_alg_cbc_des3_ede;
 extern struct safexcel_alg_template safexcel_alg_ecb_aes;
 extern struct safexcel_alg_template safexcel_alg_cbc_aes;
 extern struct safexcel_alg_template safexcel_alg_cfb_aes;
+extern struct safexcel_alg_template safexcel_alg_ofb_aes;
 extern struct safexcel_alg_template safexcel_alg_ctr_aes;
 extern struct safexcel_alg_template safexcel_alg_md5;
 extern struct safexcel_alg_template safexcel_alg_sha1;

drivers/crypto/inside-secure/safexcel_cipher.c

@@ -1172,6 +1172,42 @@ struct safexcel_alg_template safexcel_alg_cfb_aes = {
 	},
 };
 
+static int safexcel_skcipher_aes_ofb_cra_init(struct crypto_tfm *tfm)
+{
+	struct safexcel_cipher_ctx *ctx = crypto_tfm_ctx(tfm);
+
+	safexcel_skcipher_cra_init(tfm);
+	ctx->alg  = SAFEXCEL_AES;
+	ctx->mode = CONTEXT_CONTROL_CRYPTO_MODE_OFB;
+	return 0;
+}
+
+struct safexcel_alg_template safexcel_alg_ofb_aes = {
+	.type = SAFEXCEL_ALG_TYPE_SKCIPHER,
+	.algo_mask = SAFEXCEL_ALG_AES | SAFEXCEL_ALG_AES_XFB,
+	.alg.skcipher = {
+		.setkey = safexcel_skcipher_aes_setkey,
+		.encrypt = safexcel_encrypt,
+		.decrypt = safexcel_decrypt,
+		.min_keysize = AES_MIN_KEY_SIZE,
+		.max_keysize = AES_MAX_KEY_SIZE,
+		.ivsize = AES_BLOCK_SIZE,
+		.base = {
+			.cra_name = "ofb(aes)",
+			.cra_driver_name = "safexcel-ofb-aes",
+			.cra_priority = SAFEXCEL_CRA_PRIORITY,
+			.cra_flags = CRYPTO_ALG_ASYNC |
+				     CRYPTO_ALG_KERN_DRIVER_ONLY,
+			.cra_blocksize = 1,
+			.cra_ctxsize = sizeof(struct safexcel_cipher_ctx),
+			.cra_alignmask = 0,
+			.cra_init = safexcel_skcipher_aes_ofb_cra_init,
+			.cra_exit = safexcel_skcipher_cra_exit,
+			.cra_module = THIS_MODULE,
+		},
+	},
+};
+
 static int safexcel_skcipher_aesctr_setkey(struct crypto_skcipher *ctfm,
 					   const u8 *key, unsigned int len)
 {