net/tls: Support 256 bit keys with TX device offload

Add the missing clause for 256 bit keys in tls_set_device_offload(), and
the needed adjustments in tls_device_fallback.c.
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Gal Pressman <gal@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/tls/tls_device.c

@@ -914,6 +914,7 @@ tls_device_reencrypt(struct sock *sk, struct tls_context *tls_ctx)
 
 	switch (tls_ctx->crypto_recv.info.cipher_type) {
 	case TLS_CIPHER_AES_GCM_128:
+	case TLS_CIPHER_AES_GCM_256:
 		break;
 	default:
 		return -EINVAL;
@@ -1111,6 +1112,11 @@ int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
 		rec_seq =
 		 ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq;
 		break;
+	case TLS_CIPHER_AES_GCM_256:
+		iv = ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->iv;
+		rec_seq =
+		 ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->rec_seq;
+		break;
 	default:
 		rc = -EINVAL;
 		goto release_netdev;

net/tls/tls_device_fallback.c

@@ -64,6 +64,7 @@ static int tls_enc_record(struct aead_request *aead_req,
 
 	switch (prot->cipher_type) {
 	case TLS_CIPHER_AES_GCM_128:
+	case TLS_CIPHER_AES_GCM_256:
 		break;
 	default:
 		return -EINVAL;
@@ -341,6 +342,9 @@ static struct sk_buff *tls_enc_skb(struct tls_context *tls_ctx,
 	case TLS_CIPHER_AES_GCM_128:
 		salt = tls_ctx->crypto_send.aes_gcm_128.salt;
 		break;
+	case TLS_CIPHER_AES_GCM_256:
+		salt = tls_ctx->crypto_send.aes_gcm_256.salt;
+		break;
 	default:
 		return NULL;
 	}
@@ -484,6 +488,9 @@ int tls_sw_fallback_init(struct sock *sk,
 	case TLS_CIPHER_AES_GCM_128:
 		key = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->key;
 		break;
+	case TLS_CIPHER_AES_GCM_256:
+		key = ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->key;
+		break;
 	default:
 		return -EINVAL;
 	}