From: Sasha Levin <sashal@kernel.org>
To: stable@vger.kernel.org
Cc: Sabrina Dubroca <sd@queasysnail.net>,
"David S. Miller" <davem@davemloft.net>,
Sasha Levin <sashal@kernel.org>
Subject: [PATCH 6.12.y 1/2] selftests: tls: add rekey tests
Date: Wed, 19 Aug 2026 07:39:43 -0400 [thread overview]
Message-ID: <20260819113944.3620902-1-sashal@kernel.org> (raw)
In-Reply-To: <2026081717-verbalize-stylist-2627@gregkh>
From: Sabrina Dubroca <sd@queasysnail.net>
[ Upstream commit 555f0edb9ff043196655a5b7cc65f67dfd05b530 ]
Test the kernel's ability to:
- update the key (but not the version or cipher), only for TLS1.3
- pause decryption after receiving a KeyUpdate message, until a new
RX key has been provided
- reflect the pause/non-readable socket in poll()
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: 1c8629651cb5 ("tls: rx: restore msg_iter before TLS 1.3 optimistic retry")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
tools/testing/selftests/net/tls.c | 458 ++++++++++++++++++++++++++++++
1 file changed, 458 insertions(+)
diff --git a/tools/testing/selftests/net/tls.c b/tools/testing/selftests/net/tls.c
index f27a12d2a2c9..1264a20c1a04 100644
--- a/tools/testing/selftests/net/tls.c
+++ b/tools/testing/selftests/net/tls.c
@@ -1649,6 +1649,464 @@ TEST_F(tls, recv_efault)
EXPECT_EQ(memcmp(rec2, recv_mem + 9, ret - 9), 0);
}
+#define TLS_RECORD_TYPE_HANDSHAKE 0x16
+/* key_update, length 1, update_not_requested */
+static const char key_update_msg[] = "\x18\x00\x00\x01\x00";
+static void tls_send_keyupdate(struct __test_metadata *_metadata, int fd)
+{
+ size_t len = sizeof(key_update_msg);
+
+ EXPECT_EQ(tls_send_cmsg(fd, TLS_RECORD_TYPE_HANDSHAKE,
+ (char *)key_update_msg, len, 0),
+ len);
+}
+
+static void tls_recv_keyupdate(struct __test_metadata *_metadata, int fd, int flags)
+{
+ char buf[100];
+
+ EXPECT_EQ(tls_recv_cmsg(_metadata, fd, TLS_RECORD_TYPE_HANDSHAKE, buf, sizeof(buf), flags),
+ sizeof(key_update_msg));
+ EXPECT_EQ(memcmp(buf, key_update_msg, sizeof(key_update_msg)), 0);
+}
+
+/* set the key to 0 then 1 for RX, immediately to 1 for TX */
+TEST_F(tls_basic, rekey_rx)
+{
+ struct tls_crypto_info_keys tls12_0, tls12_1;
+ char const *test_str = "test_message";
+ int send_len = strlen(test_str) + 1;
+ char buf[20];
+ int ret;
+
+ if (self->notls)
+ return;
+
+ tls_crypto_info_init(TLS_1_3_VERSION, TLS_CIPHER_AES_GCM_128,
+ &tls12_0, 0);
+ tls_crypto_info_init(TLS_1_3_VERSION, TLS_CIPHER_AES_GCM_128,
+ &tls12_1, 1);
+
+ ret = setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12_1, tls12_1.len);
+ ASSERT_EQ(ret, 0);
+
+ ret = setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12_0, tls12_0.len);
+ ASSERT_EQ(ret, 0);
+
+ ret = setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12_1, tls12_1.len);
+ EXPECT_EQ(ret, 0);
+
+ EXPECT_EQ(send(self->fd, test_str, send_len, 0), send_len);
+ EXPECT_EQ(recv(self->cfd, buf, send_len, 0), send_len);
+ EXPECT_EQ(memcmp(buf, test_str, send_len), 0);
+}
+
+/* set the key to 0 then 1 for TX, immediately to 1 for RX */
+TEST_F(tls_basic, rekey_tx)
+{
+ struct tls_crypto_info_keys tls12_0, tls12_1;
+ char const *test_str = "test_message";
+ int send_len = strlen(test_str) + 1;
+ char buf[20];
+ int ret;
+
+ if (self->notls)
+ return;
+
+ tls_crypto_info_init(TLS_1_3_VERSION, TLS_CIPHER_AES_GCM_128,
+ &tls12_0, 0);
+ tls_crypto_info_init(TLS_1_3_VERSION, TLS_CIPHER_AES_GCM_128,
+ &tls12_1, 1);
+
+ ret = setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12_0, tls12_0.len);
+ ASSERT_EQ(ret, 0);
+
+ ret = setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12_1, tls12_1.len);
+ ASSERT_EQ(ret, 0);
+
+ ret = setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12_1, tls12_1.len);
+ EXPECT_EQ(ret, 0);
+
+ EXPECT_EQ(send(self->fd, test_str, send_len, 0), send_len);
+ EXPECT_EQ(recv(self->cfd, buf, send_len, 0), send_len);
+ EXPECT_EQ(memcmp(buf, test_str, send_len), 0);
+}
+
+TEST_F(tls, rekey)
+{
+ char const *test_str_1 = "test_message_before_rekey";
+ char const *test_str_2 = "test_message_after_rekey";
+ struct tls_crypto_info_keys tls12;
+ int send_len;
+ char buf[100];
+
+ if (variant->tls_version != TLS_1_3_VERSION)
+ return;
+
+ /* initial send/recv */
+ send_len = strlen(test_str_1) + 1;
+ EXPECT_EQ(send(self->fd, test_str_1, send_len, 0), send_len);
+ EXPECT_EQ(recv(self->cfd, buf, send_len, 0), send_len);
+ EXPECT_EQ(memcmp(buf, test_str_1, send_len), 0);
+
+ /* update TX key */
+ tls_send_keyupdate(_metadata, self->fd);
+ tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+ EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), 0);
+
+ /* send after rekey */
+ send_len = strlen(test_str_2) + 1;
+ EXPECT_EQ(send(self->fd, test_str_2, send_len, 0), send_len);
+
+ /* can't receive the KeyUpdate without a control message */
+ EXPECT_EQ(recv(self->cfd, buf, send_len, 0), -1);
+
+ /* get KeyUpdate */
+ tls_recv_keyupdate(_metadata, self->cfd, 0);
+
+ /* recv blocking -> -EKEYEXPIRED */
+ EXPECT_EQ(recv(self->cfd, buf, sizeof(buf), 0), -1);
+ EXPECT_EQ(errno, EKEYEXPIRED);
+
+ /* recv non-blocking -> -EKEYEXPIRED */
+ EXPECT_EQ(recv(self->cfd, buf, sizeof(buf), MSG_DONTWAIT), -1);
+ EXPECT_EQ(errno, EKEYEXPIRED);
+
+ /* update RX key */
+ EXPECT_EQ(setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12, tls12.len), 0);
+
+ /* recv after rekey */
+ EXPECT_NE(recv(self->cfd, buf, send_len, 0), -1);
+ EXPECT_EQ(memcmp(buf, test_str_2, send_len), 0);
+}
+
+TEST_F(tls, rekey_fail)
+{
+ char const *test_str_1 = "test_message_before_rekey";
+ char const *test_str_2 = "test_message_after_rekey";
+ struct tls_crypto_info_keys tls12;
+ int send_len;
+ char buf[100];
+
+ /* initial send/recv */
+ send_len = strlen(test_str_1) + 1;
+ EXPECT_EQ(send(self->fd, test_str_1, send_len, 0), send_len);
+ EXPECT_EQ(recv(self->cfd, buf, send_len, 0), send_len);
+ EXPECT_EQ(memcmp(buf, test_str_1, send_len), 0);
+
+ /* update TX key */
+ tls_send_keyupdate(_metadata, self->fd);
+
+ if (variant->tls_version != TLS_1_3_VERSION) {
+ /* just check that rekey is not supported and return */
+ tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+ EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), -1);
+ EXPECT_EQ(errno, EBUSY);
+ return;
+ }
+
+ /* successful update */
+ tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+ EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), 0);
+
+ /* invalid update: change of version */
+ tls_crypto_info_init(TLS_1_2_VERSION, variant->cipher_type, &tls12, 1);
+ EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), -1);
+ EXPECT_EQ(errno, EINVAL);
+
+ /* invalid update (RX socket): change of version */
+ tls_crypto_info_init(TLS_1_2_VERSION, variant->cipher_type, &tls12, 1);
+ EXPECT_EQ(setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12, tls12.len), -1);
+ EXPECT_EQ(errno, EINVAL);
+
+ /* invalid update: change of cipher */
+ if (variant->cipher_type == TLS_CIPHER_AES_GCM_256)
+ tls_crypto_info_init(variant->tls_version, TLS_CIPHER_CHACHA20_POLY1305, &tls12, 1);
+ else
+ tls_crypto_info_init(variant->tls_version, TLS_CIPHER_AES_GCM_256, &tls12, 1);
+ EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), -1);
+ EXPECT_EQ(errno, EINVAL);
+
+ /* send after rekey, the invalid updates shouldn't have an effect */
+ send_len = strlen(test_str_2) + 1;
+ EXPECT_EQ(send(self->fd, test_str_2, send_len, 0), send_len);
+
+ /* can't receive the KeyUpdate without a control message */
+ EXPECT_EQ(recv(self->cfd, buf, send_len, 0), -1);
+
+ /* get KeyUpdate */
+ tls_recv_keyupdate(_metadata, self->cfd, 0);
+
+ /* recv blocking -> -EKEYEXPIRED */
+ EXPECT_EQ(recv(self->cfd, buf, sizeof(buf), 0), -1);
+ EXPECT_EQ(errno, EKEYEXPIRED);
+
+ /* recv non-blocking -> -EKEYEXPIRED */
+ EXPECT_EQ(recv(self->cfd, buf, sizeof(buf), MSG_DONTWAIT), -1);
+ EXPECT_EQ(errno, EKEYEXPIRED);
+
+ /* update RX key */
+ tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+ EXPECT_EQ(setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12, tls12.len), 0);
+
+ /* recv after rekey */
+ EXPECT_NE(recv(self->cfd, buf, send_len, 0), -1);
+ EXPECT_EQ(memcmp(buf, test_str_2, send_len), 0);
+}
+
+TEST_F(tls, rekey_peek)
+{
+ char const *test_str_1 = "test_message_before_rekey";
+ struct tls_crypto_info_keys tls12;
+ int send_len;
+ char buf[100];
+
+ if (variant->tls_version != TLS_1_3_VERSION)
+ return;
+
+ send_len = strlen(test_str_1) + 1;
+ EXPECT_EQ(send(self->fd, test_str_1, send_len, 0), send_len);
+
+ /* update TX key */
+ tls_send_keyupdate(_metadata, self->fd);
+ tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+ EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), 0);
+
+ EXPECT_EQ(recv(self->cfd, buf, sizeof(buf), MSG_PEEK), send_len);
+ EXPECT_EQ(memcmp(buf, test_str_1, send_len), 0);
+
+ EXPECT_EQ(recv(self->cfd, buf, send_len, 0), send_len);
+ EXPECT_EQ(memcmp(buf, test_str_1, send_len), 0);
+
+ /* can't receive the KeyUpdate without a control message */
+ EXPECT_EQ(recv(self->cfd, buf, send_len, MSG_PEEK), -1);
+
+ /* peek KeyUpdate */
+ tls_recv_keyupdate(_metadata, self->cfd, MSG_PEEK);
+
+ /* get KeyUpdate */
+ tls_recv_keyupdate(_metadata, self->cfd, 0);
+
+ /* update RX key */
+ EXPECT_EQ(setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12, tls12.len), 0);
+}
+
+TEST_F(tls, splice_rekey)
+{
+ int send_len = TLS_PAYLOAD_MAX_LEN / 2;
+ char mem_send[TLS_PAYLOAD_MAX_LEN];
+ char mem_recv[TLS_PAYLOAD_MAX_LEN];
+ struct tls_crypto_info_keys tls12;
+ int p[2];
+
+ if (variant->tls_version != TLS_1_3_VERSION)
+ return;
+
+ memrnd(mem_send, sizeof(mem_send));
+
+ ASSERT_GE(pipe(p), 0);
+ EXPECT_EQ(send(self->fd, mem_send, send_len, 0), send_len);
+
+ /* update TX key */
+ tls_send_keyupdate(_metadata, self->fd);
+ tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+ EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), 0);
+
+ EXPECT_EQ(send(self->fd, mem_send, send_len, 0), send_len);
+
+ EXPECT_EQ(splice(self->cfd, NULL, p[1], NULL, TLS_PAYLOAD_MAX_LEN, 0), send_len);
+ EXPECT_EQ(read(p[0], mem_recv, send_len), send_len);
+ EXPECT_EQ(memcmp(mem_send, mem_recv, send_len), 0);
+
+ /* can't splice the KeyUpdate */
+ EXPECT_EQ(splice(self->cfd, NULL, p[1], NULL, TLS_PAYLOAD_MAX_LEN, 0), -1);
+ EXPECT_EQ(errno, EINVAL);
+
+ /* peek KeyUpdate */
+ tls_recv_keyupdate(_metadata, self->cfd, MSG_PEEK);
+
+ /* get KeyUpdate */
+ tls_recv_keyupdate(_metadata, self->cfd, 0);
+
+ /* can't splice before updating the key */
+ EXPECT_EQ(splice(self->cfd, NULL, p[1], NULL, TLS_PAYLOAD_MAX_LEN, 0), -1);
+ EXPECT_EQ(errno, EKEYEXPIRED);
+
+ /* update RX key */
+ EXPECT_EQ(setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12, tls12.len), 0);
+
+ EXPECT_EQ(splice(self->cfd, NULL, p[1], NULL, TLS_PAYLOAD_MAX_LEN, 0), send_len);
+ EXPECT_EQ(read(p[0], mem_recv, send_len), send_len);
+ EXPECT_EQ(memcmp(mem_send, mem_recv, send_len), 0);
+}
+
+TEST_F(tls, rekey_peek_splice)
+{
+ char const *test_str_1 = "test_message_before_rekey";
+ struct tls_crypto_info_keys tls12;
+ int send_len;
+ char buf[100];
+ char mem_recv[TLS_PAYLOAD_MAX_LEN];
+ int p[2];
+
+ if (variant->tls_version != TLS_1_3_VERSION)
+ return;
+
+ ASSERT_GE(pipe(p), 0);
+
+ send_len = strlen(test_str_1) + 1;
+ EXPECT_EQ(send(self->fd, test_str_1, send_len, 0), send_len);
+
+ /* update TX key */
+ tls_send_keyupdate(_metadata, self->fd);
+ tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+ EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), 0);
+
+ EXPECT_EQ(recv(self->cfd, buf, sizeof(buf), MSG_PEEK), send_len);
+ EXPECT_EQ(memcmp(buf, test_str_1, send_len), 0);
+
+ EXPECT_EQ(splice(self->cfd, NULL, p[1], NULL, TLS_PAYLOAD_MAX_LEN, 0), send_len);
+ EXPECT_EQ(read(p[0], mem_recv, send_len), send_len);
+ EXPECT_EQ(memcmp(mem_recv, test_str_1, send_len), 0);
+}
+
+TEST_F(tls, rekey_getsockopt)
+{
+ struct tls_crypto_info_keys tls12;
+ struct tls_crypto_info_keys tls12_get;
+ socklen_t len;
+
+ tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 0);
+
+ len = tls12.len;
+ EXPECT_EQ(getsockopt(self->fd, SOL_TLS, TLS_TX, &tls12_get, &len), 0);
+ EXPECT_EQ(len, tls12.len);
+ EXPECT_EQ(memcmp(&tls12_get, &tls12, tls12.len), 0);
+
+ len = tls12.len;
+ EXPECT_EQ(getsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12_get, &len), 0);
+ EXPECT_EQ(len, tls12.len);
+ EXPECT_EQ(memcmp(&tls12_get, &tls12, tls12.len), 0);
+
+ if (variant->tls_version != TLS_1_3_VERSION)
+ return;
+
+ tls_send_keyupdate(_metadata, self->fd);
+ tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+ EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), 0);
+
+ tls_recv_keyupdate(_metadata, self->cfd, 0);
+ EXPECT_EQ(setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12, tls12.len), 0);
+
+ len = tls12.len;
+ EXPECT_EQ(getsockopt(self->fd, SOL_TLS, TLS_TX, &tls12_get, &len), 0);
+ EXPECT_EQ(len, tls12.len);
+ EXPECT_EQ(memcmp(&tls12_get, &tls12, tls12.len), 0);
+
+ len = tls12.len;
+ EXPECT_EQ(getsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12_get, &len), 0);
+ EXPECT_EQ(len, tls12.len);
+ EXPECT_EQ(memcmp(&tls12_get, &tls12, tls12.len), 0);
+}
+
+TEST_F(tls, rekey_poll_pending)
+{
+ char const *test_str = "test_message_after_rekey";
+ struct tls_crypto_info_keys tls12;
+ struct pollfd pfd = { };
+ int send_len;
+ int ret;
+
+ if (variant->tls_version != TLS_1_3_VERSION)
+ return;
+
+ /* update TX key */
+ tls_send_keyupdate(_metadata, self->fd);
+ tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+ EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), 0);
+
+ /* get KeyUpdate */
+ tls_recv_keyupdate(_metadata, self->cfd, 0);
+
+ /* send immediately after rekey */
+ send_len = strlen(test_str) + 1;
+ EXPECT_EQ(send(self->fd, test_str, send_len, 0), send_len);
+
+ /* key hasn't been updated, expect cfd to be non-readable */
+ pfd.fd = self->cfd;
+ pfd.events = POLLIN;
+ EXPECT_EQ(poll(&pfd, 1, 0), 0);
+
+ ret = fork();
+ ASSERT_GE(ret, 0);
+
+ if (ret) {
+ int pid2, status;
+
+ /* wait before installing the new key */
+ sleep(1);
+
+ /* update RX key while poll() is sleeping */
+ EXPECT_EQ(setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12, tls12.len), 0);
+
+ pid2 = wait(&status);
+ EXPECT_EQ(pid2, ret);
+ EXPECT_EQ(status, 0);
+ } else {
+ pfd.fd = self->cfd;
+ pfd.events = POLLIN;
+ EXPECT_EQ(poll(&pfd, 1, 5000), 1);
+
+ exit(!__test_passed(_metadata));
+ }
+}
+
+TEST_F(tls, rekey_poll_delay)
+{
+ char const *test_str = "test_message_after_rekey";
+ struct tls_crypto_info_keys tls12;
+ struct pollfd pfd = { };
+ int send_len;
+ int ret;
+
+ if (variant->tls_version != TLS_1_3_VERSION)
+ return;
+
+ /* update TX key */
+ tls_send_keyupdate(_metadata, self->fd);
+ tls_crypto_info_init(variant->tls_version, variant->cipher_type, &tls12, 1);
+ EXPECT_EQ(setsockopt(self->fd, SOL_TLS, TLS_TX, &tls12, tls12.len), 0);
+
+ /* get KeyUpdate */
+ tls_recv_keyupdate(_metadata, self->cfd, 0);
+
+ ret = fork();
+ ASSERT_GE(ret, 0);
+
+ if (ret) {
+ int pid2, status;
+
+ /* wait before installing the new key */
+ sleep(1);
+
+ /* update RX key while poll() is sleeping */
+ EXPECT_EQ(setsockopt(self->cfd, SOL_TLS, TLS_RX, &tls12, tls12.len), 0);
+
+ sleep(1);
+ send_len = strlen(test_str) + 1;
+ EXPECT_EQ(send(self->fd, test_str, send_len, 0), send_len);
+
+ pid2 = wait(&status);
+ EXPECT_EQ(pid2, ret);
+ EXPECT_EQ(status, 0);
+ } else {
+ pfd.fd = self->cfd;
+ pfd.events = POLLIN;
+ EXPECT_EQ(poll(&pfd, 1, 5000), 1);
+ exit(!__test_passed(_metadata));
+ }
+}
+
FIXTURE(tls_err)
{
int fd, cfd;
--
2.53.0
next prev parent reply other threads:[~2026-08-19 11:39 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-08-17 12:48 FAILED: patch "[PATCH] tls: rx: restore msg_iter before TLS 1.3 optimistic retry" failed to apply to 6.12-stable tree gregkh
2026-08-19 11:39 ` Sasha Levin [this message]
2026-08-19 11:39 ` [PATCH 6.12.y 2/2] tls: rx: restore msg_iter before TLS 1.3 optimistic retry Sasha Levin
2026-08-19 15:19 ` [PATCH 6.12.y 1/2] selftests: tls: add rekey tests Sabrina Dubroca
2026-08-21 16:51 ` Sasha Levin
2026-08-21 20:10 ` Sabrina Dubroca
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