selftests: tls: fix chacha+bidir tests

ChaCha support did not adjust the bidirectional test.
We need to set up KTLS in reverse direction correctly,
otherwise these two cases will fail:

  tls.12_chacha.bidir
  tls.13_chacha.bidir

Fixes: 4f336e88 ("selftests/tls: add CHACHA20-POLY1305 to tls selftests")
Signed-off-by: NJakub Kicinski <kuba@kernel.org>
Acked-by: NVadim Fedorenko <vfedorenko@novek.ru>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

tools/testing/selftests/net/tls.c

@@ -25,6 +25,35 @@
 #define TLS_PAYLOAD_MAX_LEN 16384
 #define SOL_TLS 282
 
+struct tls_crypto_info_keys {
+	union {
+		struct tls12_crypto_info_aes_gcm_128 aes128;
+		struct tls12_crypto_info_chacha20_poly1305 chacha20;
+	};
+	size_t len;
+};
+
+static void tls_crypto_info_init(uint16_t tls_version, uint16_t cipher_type,
+				 struct tls_crypto_info_keys *tls12)
+{
+	memset(tls12, 0, sizeof(*tls12));
+
+	switch (cipher_type) {
+	case TLS_CIPHER_CHACHA20_POLY1305:
+		tls12->len = sizeof(struct tls12_crypto_info_chacha20_poly1305);
+		tls12->chacha20.info.version = tls_version;
+		tls12->chacha20.info.cipher_type = cipher_type;
+		break;
+	case TLS_CIPHER_AES_GCM_128:
+		tls12->len = sizeof(struct tls12_crypto_info_aes_gcm_128);
+		tls12->aes128.info.version = tls_version;
+		tls12->aes128.info.cipher_type = cipher_type;
+		break;
+	default:
+		break;
+	}
+}
+
 static void memrnd(void *s, size_t n)
 {
 	int *dword = s;
@@ -145,33 +174,16 @@ FIXTURE_VARIANT_ADD(tls, 13_chacha)
 
 FIXTURE_SETUP(tls)
 {
-	union {
-		struct tls12_crypto_info_aes_gcm_128 aes128;
-		struct tls12_crypto_info_chacha20_poly1305 chacha20;
-	} tls12;
+	struct tls_crypto_info_keys tls12;
 	struct sockaddr_in addr;
 	socklen_t len;
 	int sfd, ret;
-	size_t tls12_sz;
 
 	self->notls = false;
 	len = sizeof(addr);
 
-	memset(&tls12, 0, sizeof(tls12));
-	switch (variant->cipher_type) {
-	case TLS_CIPHER_CHACHA20_POLY1305:
-		tls12_sz = sizeof(struct tls12_crypto_info_chacha20_poly1305);
-		tls12.chacha20.info.version = variant->tls_version;
-		tls12.chacha20.info.cipher_type = variant->cipher_type;
-		break;
-	case TLS_CIPHER_AES_GCM_128:
-		tls12_sz = sizeof(struct tls12_crypto_info_aes_gcm_128);
-		tls12.aes128.info.version = variant->tls_version;
-		tls12.aes128.info.cipher_type = variant->cipher_type;
-		break;
-	default:
-		tls12_sz = 0;
-	}
+	tls_crypto_info_init(variant->tls_version, variant->cipher_type,
+			     &tls12);
 
 	addr.sin_family = AF_INET;
 	addr.sin_addr.s_addr = htonl(INADDR_ANY);
@@ -199,7 +211,7 @@ FIXTURE_SETUP(tls)
 
 	if (!self->notls) {
 		ret = setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12,
-				 tls12_sz);
+				 tls12.len);
 		ASSERT_EQ(ret, 0);
 	}
 
@@ -212,7 +224,7 @@ FIXTURE_SETUP(tls)
 		ASSERT_EQ(ret, 0);
 
 		ret = setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12,
-				 tls12_sz);
+				 tls12.len);
 		ASSERT_EQ(ret, 0);
 	}
 
@@ -854,18 +866,17 @@ TEST_F(tls, bidir)
 	int ret;
 
 	if (!self->notls) {
-		struct tls12_crypto_info_aes_gcm_128 tls12;
+		struct tls_crypto_info_keys tls12;
 
-		memset(&tls12, 0, sizeof(tls12));
-		tls12.info.version = variant->tls_version;
-		tls12.info.cipher_type = TLS_CIPHER_AES_GCM_128;
+		tls_crypto_info_init(variant->tls_version, variant->cipher_type,
+				     &tls12);
 
 		ret = setsockopt(self->fd, SOL_TLS, TLS_RX, &tls12,
-				 sizeof(tls12));
+				 tls12.len);
 		ASSERT_EQ(ret, 0);
 
 		ret = setsockopt(self->cfd, SOL_TLS, TLS_TX, &tls12,
-				 sizeof(tls12));
+				 tls12.len);
 		ASSERT_EQ(ret, 0);
 	}