[PATCH v2 15/18] thunderbolt: Add 'boot' attribute for devices

Mika Westerberg
2018-02-26T14:14:36Z

From: Yehezkel Bernat <yehezkel.bernat@intel.com>

In various cases, Thunderbolt device can be connected by ICM on boot
without waiting for approval from user. Most cases are related to
OEM-specific BIOS configurations. This information is interesting for
user-space as if the device isn't in SW ACL, it may create a friction in
the user experience where the device is automatically authorized if it's
connected on boot but requires an explicit user action if connected
after OS is up. User-space can use this information to suggest adding
the device to SW ACL for auto-authorization on later connections.

Signed-off-by: Yehezkel Bernat <yehezkel.bernat@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
---
Documentation/ABI/testing/sysfs-bus-thunderbolt | 7 +++++++
drivers/thunderbolt/icm.c | 12 ++++++++----
drivers/thunderbolt/switch.c | 14 ++++++++++++++
drivers/thunderbolt/tb.h | 2 ++
drivers/thunderbolt/tb_msgs.h | 1 +
5 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-bus-thunderbolt b/Documentation/ABI/testing/sysfs-bus-thunderbolt
index 93798c02e28b..1f145b727d76 100644
--- a/Documentation/ABI/testing/sysfs-bus-thunderbolt
+++ b/Documentation/ABI/testing/sysfs-bus-thunderbolt
@@ -38,6 +38,13 @@ Description: This attribute is used to authorize Thunderbolt devices
the device did not contain a key at all, and
EKEYREJECTED if the challenge response did not match.

+What: /sys/bus/thunderbolt/devices/.../boot
+Date: Jun 2018
+KernelVersion: 4.17
+Contact: thunderbolt-software@lists.01.org
+Description: This attribute contains 1 if Thunderbolt device was already
+ authorized on boot and 0 otherwise.
+
What: /sys/bus/thunderbolt/devices/.../key
Date: Sep 2017
KernelVersion: 4.13
diff --git a/drivers/thunderbolt/icm.c b/drivers/thunderbolt/icm.c
index c7cb5cd36f68..1d6bbfc558f4 100644
--- a/drivers/thunderbolt/icm.c
+++ b/drivers/thunderbolt/icm.c
@@ -402,7 +402,7 @@ static int icm_fr_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd)
static void add_switch(struct tb_switch *parent_sw, u64 route,
const uuid_t *uuid, u8 connection_id, u8 connection_key,
u8 link, u8 depth, enum tb_security_level security_level,
- bool authorized)
+ bool authorized, bool boot)
{
struct tb_switch *sw;

@@ -417,6 +417,7 @@ static void add_switch(struct tb_switch *parent_sw, u64 route,
sw->depth = depth;
sw->authorized = authorized;
sw->security_level = security_level;
+ sw->boot = boot;

/* Link the two switches now */
tb_port_at(route, parent_sw)->remote = tb_upstream_port(sw);
@@ -431,7 +432,7 @@ static void add_switch(struct tb_switch *parent_sw, u64 route,

static void update_switch(struct tb_switch *parent_sw, struct tb_switch *sw,
u64 route, u8 connection_id, u8 connection_key,
- u8 link, u8 depth)
+ u8 link, u8 depth, bool boot)
{
/* Disconnect from parent */
tb_port_at(tb_route(sw), parent_sw)->remote = NULL;
@@ -445,6 +446,7 @@ static void update_switch(struct tb_switch *parent_sw, struct tb_switch *sw,
sw->connection_key = connection_key;
sw->link = link;
sw->depth = depth;
+ sw->boot = boot;

/* This switch still exists */
sw->is_unplugged = false;
@@ -504,6 +506,7 @@ icm_fr_device_connected(struct tb *tb, const struct icm_pkg_header *hdr)
bool authorized = false;
struct tb_xdomain *xd;
u8 link, depth;
+ bool boot;
u64 route;
int ret;

@@ -513,6 +516,7 @@ icm_fr_device_connected(struct tb *tb, const struct icm_pkg_header *hdr)
authorized = pkg->link_info & ICM_LINK_INFO_APPROVED;
security_level = (pkg->hdr.flags & ICM_FLAGS_SLEVEL_MASK) >>
ICM_FLAGS_SLEVEL_SHIFT;
+ boot = pkg->link_info & ICM_LINK_INFO_BOOT;

if (pkg->link_info & ICM_LINK_INFO_REJECTED) {
tb_info(tb, "switch at %u.%u was rejected by ICM firmware\n",
@@ -546,7 +550,7 @@ icm_fr_device_connected(struct tb *tb, const struct icm_pkg_header *hdr)
if (sw->depth == depth && sw_phy_port == phy_port &&
!!sw->authorized == authorized) {
update_switch(parent_sw, sw, route, pkg->connection_id,
- pkg->connection_key, link, depth);
+ pkg->connection_key, link, depth, boot);
tb_switch_put(sw);
return;
}
@@ -595,7 +599,7 @@ icm_fr_device_connected(struct tb *tb, const struct icm_pkg_header *hdr)

add_switch(parent_sw, route, &pkg->ep_uuid, pkg->connection_id,
pkg->connection_key, link, depth, security_level,
- authorized);
+ authorized, boot);

tb_switch_put(parent_sw);
}
diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index 4e2b2097bbfc..e9e30aaab2a3 100644
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -775,6 +775,15 @@ static ssize_t authorized_store(struct device *dev,
}
static DEVICE_ATTR_RW(authorized);

+static ssize_t boot_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct tb_switch *sw = tb_to_switch(dev);
+
+ return sprintf(buf, "%u\n", sw->boot);
+}
+static DEVICE_ATTR_RO(boot);
+
static ssize_t device_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
@@ -951,6 +960,7 @@ static DEVICE_ATTR_RO(unique_id);

static struct attribute *switch_attrs[] = {
&dev_attr_authorized.attr,
+ &dev_attr_boot.attr,
&dev_attr_device.attr,
&dev_attr_device_name.attr,
&dev_attr_key.attr,
@@ -979,6 +989,10 @@ static umode_t switch_attr_is_visible(struct kobject *kobj,
if (sw->dma_port)
return attr->mode;
return 0;
+ } else if (attr == &dev_attr_boot.attr) {
+ if (tb_route(sw))
+ return attr->mode;
+ return 0;
}

return sw->safe_mode ? 0 : attr->mode;
diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
index 2cd6085a6e10..9c9cef875ca8 100644
--- a/drivers/thunderbolt/tb.h
+++ b/drivers/thunderbolt/tb.h
@@ -66,6 +66,7 @@ struct tb_switch_nvm {
* @nvm: Pointer to the NVM if the switch has one (%NULL otherwise)
* @no_nvm_upgrade: Prevent NVM upgrade of this switch
* @safe_mode: The switch is in safe-mode
+ * @boot: Whether the switch was already authorized on boot or not
* @authorized: Whether the switch is authorized by user or policy
* @work: Work used to automatically authorize a switch
* @security_level: Switch supported security level
@@ -99,6 +100,7 @@ struct tb_switch {
struct tb_switch_nvm *nvm;
bool no_nvm_upgrade;
bool safe_mode;
+ bool boot;
unsigned int authorized;
struct work_struct work;
enum tb_security_level security_level;
diff --git a/drivers/thunderbolt/tb_msgs.h b/drivers/thunderbolt/tb_msgs.h
index 931db2a7c7b3..9f52f842257a 100644
--- a/drivers/thunderbolt/tb_msgs.h
+++ b/drivers/thunderbolt/tb_msgs.h
@@ -179,6 +179,7 @@ struct icm_fr_event_device_connected {
#define ICM_LINK_INFO_DEPTH_MASK GENMASK(7, 4)
#define ICM_LINK_INFO_APPROVED BIT(8)
#define ICM_LINK_INFO_REJECTED BIT(9)
+#define ICM_LINK_INFO_BOOT BIT(10)

struct icm_fr_pkg_approve_device {
struct icm_pkg_header hdr;
--
2.16.1