[PATCH 13/14] nvmet-tcp: enable TLS handshake upcall
Hannes Reinecke
hare at suse.de
Mon Aug 7 02:15:53 PDT 2023
On 8/7/23 10:51, Sagi Grimberg wrote:
>
>
> On 8/3/23 13:51, Hannes Reinecke wrote:
>> Add functions to start the TLS handshake upcall when
>> the TCP TSAS sectype is set to 'tls1.3' and add a config
>> option NVME_TARGET_TCP_TLS.
>>
>> Signed-off-by: Hannes Reincke <hare at suse.de>
>> ---
>> drivers/nvme/target/Kconfig | 14 ++++
>> drivers/nvme/target/configfs.c | 63 +++++++++++++++-
>> drivers/nvme/target/nvmet.h | 1 +
>> drivers/nvme/target/tcp.c | 133 +++++++++++++++++++++++++++++++--
>> 4 files changed, 203 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/nvme/target/Kconfig b/drivers/nvme/target/Kconfig
>> index 79fc64035ee3..15af2b4341f6 100644
>> --- a/drivers/nvme/target/Kconfig
>> +++ b/drivers/nvme/target/Kconfig
>> @@ -84,6 +84,20 @@ config NVME_TARGET_TCP
>> If unsure, say N.
>> +config NVME_TARGET_TCP_TLS
>> + bool "NVMe over Fabrics TCP target TLS encryption support"
>> + depends on NVME_TARGET_TCP
>> + select NVME_COMMON
>> + select NVME_KEYRING
>> + select NET_HANDSHAKE
>> + help
>> + Enables TLS encryption for the NVMe TCP target using the
>> netlink handshake API.
>> +
>> + The TLS handshake daemon is availble at
>> + https://github.com/oracle/ktls-utils.
>> +
>> + If unsure, say N.
>> +
>> config NVME_TARGET_AUTH
>> bool "NVMe over Fabrics In-band Authentication support"
>> depends on NVME_TARGET
>> diff --git a/drivers/nvme/target/configfs.c
>> b/drivers/nvme/target/configfs.c
>> index 7f826ac8b75c..49b407702ad5 100644
>> --- a/drivers/nvme/target/configfs.c
>> +++ b/drivers/nvme/target/configfs.c
>> @@ -15,6 +15,7 @@
>> #ifdef CONFIG_NVME_TARGET_AUTH
>> #include <linux/nvme-auth.h>
>> #endif
>> +#include <linux/nvme-keyring.h>
>> #include <crypto/hash.h>
>> #include <crypto/kpp.h>
>> @@ -159,10 +160,15 @@ static const struct nvmet_type_name_map
>> nvmet_addr_treq[] = {
>> { NVMF_TREQ_NOT_REQUIRED, "not required" },
>> };
>> +static inline u8 nvmet_port_treq(struct nvmet_port *port)
>> +{
>> + return (port->disc_addr.treq & NVME_TREQ_SECURE_CHANNEL_MASK);
>> +}
>> +
>> static ssize_t nvmet_addr_treq_show(struct config_item *item, char
>> *page)
>> {
>> - u8 treq = to_nvmet_port(item)->disc_addr.treq &
>> - NVME_TREQ_SECURE_CHANNEL_MASK;
>> + struct nvmet_port *port = to_nvmet_port(item);
>> + u8 treq = nvmet_port_treq(port);
>> int i;
>> for (i = 0; i < ARRAY_SIZE(nvmet_addr_treq); i++) {
>> @@ -174,11 +180,16 @@ static ssize_t nvmet_addr_treq_show(struct
>> config_item *item, char *page)
>> return snprintf(page, PAGE_SIZE, "\n");
>> }
>> +static inline u8 nvmet_port_treq_mask(struct nvmet_port *port)
>> +{
>> + return (port->disc_addr.treq & ~NVME_TREQ_SECURE_CHANNEL_MASK);
>> +}
>> +
>> static ssize_t nvmet_addr_treq_store(struct config_item *item,
>> const char *page, size_t count)
>> {
>> struct nvmet_port *port = to_nvmet_port(item);
>> - u8 treq = port->disc_addr.treq & ~NVME_TREQ_SECURE_CHANNEL_MASK;
>> + u8 treq = nvmet_port_treq_mask(port);
>> int i;
>> if (nvmet_is_port_enabled(port, __func__))
>> @@ -193,6 +204,23 @@ static ssize_t nvmet_addr_treq_store(struct
>> config_item *item,
>> return -EINVAL;
>> found:
>> + if (port->disc_addr.trtype == NVMF_TRTYPE_TCP) {
>> + if (!IS_ENABLED(CONFIG_NVME_TARGET_TCP_TLS)) {
>> + pr_err("TLS is not supported\n");
>> + return -EINVAL;
>> + }
>> + if (!port->keyring) {
>> + pr_err("TLS keyring not configured\n");
>> + return -EINVAL;
>> + }
>> + if (port->disc_addr.tsas.tcp.sectype !=
>> NVMF_TCP_SECTYPE_TLS13) {
>> + pr_warn("cannot change TREQ when TLS is not enabled\n");
>> + return -EINVAL;
>> + } else if (nvmet_addr_treq[i].type == NVMF_TREQ_NOT_SPECIFIED) {
>> + pr_warn("cannot set TREQ to 'not specified' when TLS is
>> enabled\n");
>> + return -EINVAL;
>> + }
>> + }
>> treq |= nvmet_addr_treq[i].type;
>> port->disc_addr.treq = treq;
>> return count;
>> @@ -371,6 +399,7 @@ static ssize_t nvmet_addr_tsas_store(struct
>> config_item *item,
>> const char *page, size_t count)
>> {
>> struct nvmet_port *port = to_nvmet_port(item);
>> + u8 treq = nvmet_port_treq_mask(port);
>> int i;
>> if (nvmet_is_port_enabled(port, __func__))
>> @@ -379,6 +408,15 @@ static ssize_t nvmet_addr_tsas_store(struct
>> config_item *item,
>> if (port->disc_addr.trtype != NVMF_TRTYPE_TCP)
>> return -EINVAL;
>> + if (!IS_ENABLED(CONFIG_NVME_TARGET_TCP_TLS)) {
>> + pr_err("TLS is not supported\n");
>> + return -EINVAL;
>> + }
>> + if (!port->keyring) {
>> + pr_err("TLS keyring not configured\n");
>> + return -EINVAL;
>> + }
>> +
>> for (i = 0; i < ARRAY_SIZE(nvmet_addr_tsas_tcp); i++) {
>> if (sysfs_streq(page, nvmet_addr_tsas_tcp[i].name))
>> goto found;
>> @@ -389,6 +427,16 @@ static ssize_t nvmet_addr_tsas_store(struct
>> config_item *item,
>> found:
>> nvmet_port_init_tsas_tcp(port, nvmet_addr_tsas_tcp[i].type);
>> + if (nvmet_addr_tsas_tcp[i].type == NVMF_TCP_SECTYPE_TLS13) {
>> + if (nvmet_port_treq(port) == NVMF_TREQ_NOT_SPECIFIED)
>> + treq |= NVMF_TREQ_REQUIRED;
>> + else
>> + treq |= nvmet_port_treq(port);
>> + } else {
>> + /* Set to 'not specified' if TLS is not enabled */
>> + treq |= NVMF_TREQ_NOT_SPECIFIED;
>> + }
>> + port->disc_addr.treq = treq;
>> return count;
>> }
>
> Can the treq/tsas be split from the actual nvmet-tcp upcall addition?
>
I guess it can; it's just that it doesn't make any sense if we don't
have the TLS upcall implemented.
>> @@ -1795,6 +1843,7 @@ static void nvmet_port_release(struct
>> config_item *item)
>> flush_workqueue(nvmet_wq);
>> list_del(&port->global_entry);
>> + key_put(port->keyring);
>> kfree(port->ana_state);
>> kfree(port);
>> }
>> @@ -1844,6 +1893,14 @@ static struct config_group
>> *nvmet_ports_make(struct config_group *group,
>> return ERR_PTR(-ENOMEM);
>> }
>> + if (nvme_keyring_id()) {
>> + port->keyring = key_lookup(nvme_keyring_id());
>> + if (IS_ERR(port->keyring)) {
>> + pr_warn("NVMe keyring not available, disabling TLS\n");
>> + port->keyring = NULL;
>> + }
>> + }
>> +
>
> Nice.
>
>> for (i = 1; i <= NVMET_MAX_ANAGRPS; i++) {
>> if (i == NVMET_DEFAULT_ANA_GRPID)
>> port->ana_state[1] = NVME_ANA_OPTIMIZED;
>> diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
>> index 8cfd60f3b564..7f9ae53c1df5 100644
>> --- a/drivers/nvme/target/nvmet.h
>> +++ b/drivers/nvme/target/nvmet.h
>> @@ -158,6 +158,7 @@ struct nvmet_port {
>> struct config_group ana_groups_group;
>> struct nvmet_ana_group ana_default_group;
>> enum nvme_ana_state *ana_state;
>> + struct key *keyring;
>> void *priv;
>> bool enabled;
>> int inline_data_size;
>> diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c
>> index fdc351f591a4..7279c994abd6 100644
>> --- a/drivers/nvme/target/tcp.c
>> +++ b/drivers/nvme/target/tcp.c
>> @@ -8,9 +8,13 @@
>> #include <linux/init.h>
>> #include <linux/slab.h>
>> #include <linux/err.h>
>> +#include <linux/key.h>
>> #include <linux/nvme-tcp.h>
>> +#include <linux/nvme-keyring.h>
>> #include <net/sock.h>
>> #include <net/tcp.h>
>> +#include <net/tls.h>
>> +#include <net/handshake.h>
>> #include <linux/inet.h>
>> #include <linux/llist.h>
>> #include <crypto/hash.h>
>> @@ -66,6 +70,16 @@ device_param_cb(idle_poll_period_usecs,
>> &set_param_ops,
>> MODULE_PARM_DESC(idle_poll_period_usecs,
>> "nvmet tcp io_work poll till idle time period in usecs:
>> Default 0");
>> +#ifdef CONFIG_NVME_TARGET_TCP_TLS
>> +/*
>> + * TLS handshake timeout
>> + */
>> +static int tls_handshake_timeout = 30;
>> +module_param(tls_handshake_timeout, int, 0644);
>> +MODULE_PARM_DESC(tls_handshake_timeout,
>> + "nvme TLS handshake timeout in seconds (default 30)");
>> +#endif
>
> On the host it is 10 and here 30? what is the source of the assymmetry?
>
Hmm. Looks like an oversight. Will be aligning them.
>> +
>> #define NVMET_TCP_RECV_BUDGET 8
>> #define NVMET_TCP_SEND_BUDGET 8
>> #define NVMET_TCP_IO_WORK_BUDGET 64
>> @@ -122,6 +136,7 @@ struct nvmet_tcp_cmd {
>> enum nvmet_tcp_queue_state {
>> NVMET_TCP_Q_CONNECTING,
>> + NVMET_TCP_Q_TLS_HANDSHAKE,
>> NVMET_TCP_Q_LIVE,
>> NVMET_TCP_Q_DISCONNECTING,
>> };
>> @@ -154,6 +169,8 @@ struct nvmet_tcp_queue {
>> bool data_digest;
>> struct ahash_request *snd_hash;
>> struct ahash_request *rcv_hash;
>> + key_serial_t tls_pskid;
>> + struct delayed_work tls_handshake_work;
>> unsigned long poll_end;
>> @@ -1285,12 +1302,12 @@ static int nvmet_tcp_try_recv(struct
>> nvmet_tcp_queue *queue,
>> static void nvmet_tcp_schedule_release_queue(struct nvmet_tcp_queue
>> *queue)
>> {
>> - spin_lock(&queue->state_lock);
>> + spin_lock_irq(&queue->state_lock);
>
> Where is this lock taken in irq context that needs disabling irq?
>
Let me check; might be that it got solved with the workqueue fixes which
went in lately.
>> if (queue->state != NVMET_TCP_Q_DISCONNECTING) {
>> queue->state = NVMET_TCP_Q_DISCONNECTING;
>> queue_work(nvmet_wq, &queue->release_work);
>> }
>> - spin_unlock(&queue->state_lock);
>> + spin_unlock_irq(&queue->state_lock);
>> }
>> static inline void nvmet_tcp_arm_queue_deadline(struct
>> nvmet_tcp_queue *queue)
>> @@ -1512,8 +1529,12 @@ static void nvmet_tcp_data_ready(struct sock *sk)
>> read_lock_bh(&sk->sk_callback_lock);
>> queue = sk->sk_user_data;
>> - if (likely(queue))
>> - queue_work_on(queue_cpu(queue), nvmet_tcp_wq, &queue->io_work);
>> + if (queue->data_ready)
>> + queue->data_ready(sk);
>> + if (likely(queue) &&
>> + queue->state != NVMET_TCP_Q_TLS_HANDSHAKE)
>> + queue_work_on(queue_cpu(queue), nvmet_tcp_wq,
>> + &queue->io_work);
>> read_unlock_bh(&sk->sk_callback_lock);
>> }
>> @@ -1621,6 +1642,85 @@ static int nvmet_tcp_set_queue_sock(struct
>> nvmet_tcp_queue *queue)
>> return ret;
>> }
>> +#ifdef CONFIG_NVME_TARGET_TCP_TLS
>> +static void nvmet_tcp_tls_queue_reset(struct nvmet_tcp_queue *queue)
>> +{
>> + spin_lock_irq(&queue->state_lock);
>> + if (queue->state != NVMET_TCP_Q_TLS_HANDSHAKE) {
>> + pr_warn("queue %d: TLS handshake already completed\n",
>> + queue->idx);
>> + spin_unlock_irq(&queue->state_lock);
>> + return;
>
> trigger fatal error here?
>
Good point.
>> + }
>> + queue->state = NVMET_TCP_Q_CONNECTING;
>> + spin_unlock_irq(&queue->state_lock);
>> +
>> + pr_debug("queue %d: resetting queue callbacks after TLS
>> handshake\n",
>> + queue->idx);
>> + /*
>> + * Set callbacks after handshake; TLS implementation
>> + * might have changed the socket callbacks.
>> + */
>> + nvmet_tcp_set_queue_sock(queue);
>> +}
>> +
>> +static void nvmet_tcp_tls_handshake_done(void *data, int status,
>> + key_serial_t peerid)
>
> lets call peerid psk_id throughout.
>
Okay.
>> +{
>> + struct nvmet_tcp_queue *queue = data;
>> +
>> + pr_debug("queue %d: TLS handshake done, key %x, status %d\n",
>> + queue->idx, peerid, status);
>> + if (!status) {
>> + spin_lock_irq(&queue->state_lock);
>> + queue->tls_pskid = peerid;
>> + spin_unlock_irq(&queue->state_lock);
>> + }
>> + cancel_delayed_work_sync(&queue->tls_handshake_work);
>
> Hmm, the cancel_delayed_work_sync is scary.
>
> What happens if it ran and already scheduled a release (which
> already ran and completed)?
>
Well, we need to stop the timeout at some point; granted, for a failure
we can just flush the workqueue, but in the success case we need
terminate the workqueue.
And nvmet_tcp_schedule_release_queue() already checks for the queue
state, so we should be (reasonably) safe.
>> + if (status)
>> + nvmet_tcp_schedule_release_queue(queue);
>> + else
>> + nvmet_tcp_tls_queue_reset(queue);
>
> What I think you need is an atomic state that one or the
> other access, and then you are fine with a normal async
> cancel of the delayed_work.
>
Hmm. I'll have a look.
>> +}
>> +
>> +static void nvmet_tcp_tls_handshake_timeout_work(struct work_struct *w)
>> +{
>> + struct nvmet_tcp_queue *queue = container_of(to_delayed_work(w),
>> + struct nvmet_tcp_queue, tls_handshake_work);
>> +
>> + pr_debug("queue %d: TLS handshake timeout\n", queue->idx);
>> + nvmet_tcp_schedule_release_queue(queue);
>> +}
>> +
>> +static int nvmet_tcp_tls_handshake(struct nvmet_tcp_queue *queue)
>> +{
>> + int ret = -EOPNOTSUPP;
>> + struct tls_handshake_args args;
>> +
>> + if (queue->state != NVMET_TCP_Q_TLS_HANDSHAKE) {
>> + pr_warn("cannot start TLS in state %d\n", queue->state);
>> + return -EINVAL;
>> + }
>> +
>> + pr_debug("queue %d: TLS ServerHello\n", queue->idx);
>> + memset(&args, 0, sizeof(args));
>> + args.ta_sock = queue->sock;
>> + args.ta_done = nvmet_tcp_tls_handshake_done;
>> + args.ta_data = queue;
>> + args.ta_keyring = key_serial(queue->port->nport->keyring);
>> + args.ta_timeout_ms = tls_handshake_timeout * 2 * 1024;
>
> * 2 * 1024 ? I didn't know we have 2048 ms in a second...
>
The '_ms' bit is just an indicator of the unit, not the value.
We don't have an 'args.ta_timeout_sec' ...
>> +
>> + ret = tls_server_hello_psk(&args, GFP_KERNEL);
>> + if (ret) {
>> + pr_err("failed to start TLS, err=%d\n", ret);
>> + } else {
>> + queue_delayed_work(nvmet_wq, &queue->tls_handshake_work,
>> + tls_handshake_timeout * HZ);
>> + }
>> + return ret;
>> +}
>> +#endif
>> +
>> static void nvmet_tcp_alloc_queue(struct nvmet_tcp_port *port,
>> struct socket *newsock)
>> {
>> @@ -1638,7 +1738,11 @@ static void nvmet_tcp_alloc_queue(struct
>> nvmet_tcp_port *port,
>> queue->port = port;
>> queue->nr_cmds = 0;
>> spin_lock_init(&queue->state_lock);
>> - queue->state = NVMET_TCP_Q_CONNECTING;
>> + if (queue->port->nport->disc_addr.tsas.tcp.sectype ==
>> + NVMF_TCP_SECTYPE_TLS13)
>> + queue->state = NVMET_TCP_Q_TLS_HANDSHAKE;
>> + else
>> + queue->state = NVMET_TCP_Q_CONNECTING;
>> INIT_LIST_HEAD(&queue->free_list);
>> init_llist_head(&queue->resp_list);
>> INIT_LIST_HEAD(&queue->resp_send_list);
>> @@ -1669,6 +1773,25 @@ static void nvmet_tcp_alloc_queue(struct
>> nvmet_tcp_port *port,
>> list_add_tail(&queue->queue_list, &nvmet_tcp_queue_list);
>> mutex_unlock(&nvmet_tcp_queue_mutex);
>> +#ifdef CONFIG_NVME_TARGET_TCP_TLS
>
> maybe the ifdef can be avoided with stubs?
>
Lemme check.
Cheers,
Hannes
--
Dr. Hannes Reinecke Kernel Storage Architect
hare at suse.de +49 911 74053 688
SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg
HRB 36809 (AG Nürnberg), Geschäftsführer: Ivo Totev, Andrew
Myers, Andrew McDonald, Martje Boudien Moerman
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