[PATCH wireless-next v4 05/21] wifi: nl80211: define interfaces for SMD BSS Transition context transfer

[Pooventhiran G <pooventhiran.g@oss.qualcomm.com>]

Define nl80211 attributes and policies required to pack SMD BSS Transition
context along with NL80211_CMD_FRAME to be sent to userspace, and to set
and get the context during roaming via current AP MLD and roaming via
target AP MLD. Without these, userspace will not be able to transport the
context to the target AP MLD, program the context on the target AP MLD TX
and RX queues, nor fetch the context on behalf of the target AP MLD if
the ST Execution frame is sent directly to the target.

Suggested-by: Jouni Malinen <jouni.malinen@oss.qualcomm.com>
Signed-off-by: Pooventhiran G <pooventhiran.g@oss.qualcomm.com>
---
 include/uapi/linux/nl80211.h | 190 +++++++++++++++++++++++++++++++++++++++++++
 net/wireless/nl80211.c       |  48 +++++++++++
 2 files changed, 238 insertions(+)

diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 81c16ea2fd34..fbc23aca006e 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -375,6 +375,19 @@
  *	on the target AP MLD while creating the station entry.
  *	%NL80211_STA_FLAG_SMD_{EXEC_CURRENT,DL_DRAIN}, on the other hand, can be
  *	set using %NL80211_CMD_SET_STATION on the current AP MLD.
+ *
+ * Drivers can use %NL80211_ATTR_SMD_CTX to pack the dynamic context of the
+ * non-AP MLD along with the ST Preparation or ST Execution Request frames in
+ * the %NL80211_CMD_FRAME event.
+ *
+ * On the target AP MLD, this collected context, received in the
+ * userspace-managed backhaul between the AP MLDs, can be programmed using
+ * %NL80211_CMD_SET_SMD_CTX.
+ *
+ * In case the non-AP MLD executes directly with the target AP MLD, the current
+ * AP MLD can request the context from the driver on the target's behalf using
+ * %NL80211_CMD_GET_SMD_CTX and the response can be reported back using
+ * %NL80211_CMD_SMD_CTX_EVENT.
  */
 
 /**
@@ -1502,6 +1515,21 @@
  *	and multiple can be nested in %NL80211_ATTR_MLO_LINKS but then the
  *	update isn't atomic if any failures happen.
  *	Only supported with %NL80211_EXT_FEATURE_UPDATE_BEACON.
+ *
+ * @NL80211_CMD_SET_SMD_CTX: Set the SMD BSS Transition dynamic context for a
+ *	non-AP MLD sent from the current AP MLD on the target AP MLD managed by
+ *	an SMD-ME. This command carries %NL80211_ATTR_MLD_ADDR,
+ *	%NL80211_ATTR_SMD_CTX_TYPE and %NL80211_ATTR_SMD_CTX. The station must
+ *	be present on the target AP MLD in the "prepared" state with a default
+ *	key installed.
+ * @NL80211_CMD_GET_SMD_CTX: Get the SMD BSS Transition dynamic context for a
+ *	non-AP MLD associated to an AP MLD managed by an SMD-ME. This command
+ *	carries %NL80211_ATTR_MLD_ADDR and %NL80211_ATTR_SMD_CTX_TYPE.
+ * @NL80211_CMD_SMD_CTX_EVENT: Event reporting the collected SMD context
+ *	(requested via %NL80211_CMD_GET_SMD_CTX) to userspace. It carries
+ *	%NL80211_ATTR_MLD_ADDR, %NL80211_ATTR_SMD_CTX_TYPE, and
+ *	%NL80211_ATTR_SMD_CTX.
+ *
  * @NL80211_CMD_MAX: highest used command number
  * @__NL80211_CMD_AFTER_LAST: internal use
  */
@@ -1784,6 +1812,10 @@ enum nl80211_commands {
 
 	NL80211_CMD_UPDATE_BEACON,
 
+	NL80211_CMD_SET_SMD_CTX,
+	NL80211_CMD_GET_SMD_CTX,
+	NL80211_CMD_SMD_CTX_EVENT,
+
 	/* add new commands above here */
 
 	/* used to define NL80211_CMD_MAX below */
@@ -3282,6 +3314,13 @@ enum nl80211_commands {
  * @NL80211_ATTR_SMD_ROAM_STA: Flag attribute to indicate that the station is
  *	created as part of SMD BSS Transition and not by typical association.
  *
+ * @NL80211_ATTR_SMD_CTX: Nested attribute associated with UHR SMD BSS
+ *	Transition data. Used with %NL80211_CMD_FRAME, %NL80211_CMD_SET_SMD_CTX,
+ *	and %NL80211_CMD_SMD_CTX_EVENT. See &enum nl80211_smd_ctx.
+ * @NL80211_ATTR_SMD_CTX_TYPE: u8 attribute specifying the type of SMD context.
+ *	Used along with %NL80211_CMD_FRAME, %NL80211_CMD_SET_SMD_CTX,
+ *	%NL80211_CMD_GET_SMD_CTX, and %NL80211_CMD_SMD_CTX_EVENT.
+ *
  * @NUM_NL80211_ATTR: total number of nl80211_attrs available
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
@@ -3892,6 +3931,9 @@ enum nl80211_attrs {
 	NL80211_ATTR_SMD_SUPPORT,
 	NL80211_ATTR_SMD_ROAM_STA,
 
+	NL80211_ATTR_SMD_CTX,
+	NL80211_ATTR_SMD_CTX_TYPE,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,
@@ -9253,4 +9295,152 @@ enum nl80211_nan_peer_map_attrs {
 
 #define NL80211_NAN_SCHED_NOT_AVAIL_SLOT 0xff
 
+/**
+ * enum nl80211_smd_ctx_type - SMD Request Type values
+ *
+ * Used with %NL80211_ATTR_SMD_CTX_TYPE.
+ *
+ * @NL80211_SMD_CTX_TYPE_PREP: SMD BSS Transition (ST) Preparation.
+ * @NL80211_SMD_CTX_TYPE_EXEC: ST Execution.
+ * @NUM_SMD_CTX_TYPES: internal.
+ * @NL80211_SMD_CTX_TYPE_MAX: Max type of ST context.
+ */
+enum nl80211_smd_ctx_type {
+	NL80211_SMD_CTX_TYPE_PREP,
+	NL80211_SMD_CTX_TYPE_EXEC,
+
+	NUM_SMD_CTX_TYPES,
+	NL80211_SMD_CTX_TYPE_MAX = NUM_SMD_CTX_TYPES - 1,
+};
+
+/**
+ * enum nl80211_smd_ctx_ba_param - SMD Block Ack Context attributes
+ *
+ * @__NL80211_SMD_CTX_BA_ATTR_INVALID: Invalid attribute.
+ * @NL80211_SMD_CTX_BA_ATTR_BUFF_SIZE: Required (u16) BA buffer size.
+ * @NL80211_SMD_CTX_BA_ATTR_POLICY: Required (u8) BA policy.
+ * @NL80211_SMD_CTX_BA_ATTR_AMSDU_SUPPORT: Flag attribute to indicate
+ *	AMSDU support.
+ * @NL80211_SMD_CTX_BA_ATTR_TIMEOUT: Required (u16) Block Ack timeout.
+ * @NL80211_SMD_CTX_BA_ATTR_EXT_NO_FRAG: Flag attribute to indicate
+ *	fragmentation support.
+ * @NL80211_SMD_CTX_BA_ATTR_EXT_FRAG_LEVEL: Required (u8) HE fragmentation
+ *	level.
+ * @NL80211_SMD_CTX_BA_ATTR_EXT_BUFF_SIZE: Required (u16) extended buffer size.
+ * @NL80211_SMD_CTX_BA_ATTR_WINSTARTO: Required (u16) Starting Sequence Number
+ *	of the BA window.
+ *	Applicable only with %NL80211_SMD_CTX_DL_ATTR_BA_PARAMS.
+ * @__NL80211_SMD_CTX_BA_ATTR_LAST: Last attribute, used internally.
+ * @NL80211_SMD_CTX_BA_ATTR_MAX: Max attribute.
+ *
+ * Used with %NL80211_SMD_CTX_DL_ATTR_BA_PARAMS and
+ * %NL80211_SMD_CTX_UL_ATTR_BA_PARAMS.
+ */
+enum nl80211_smd_ctx_ba_param {
+	__NL80211_SMD_CTX_BA_ATTR_INVALID,
+	NL80211_SMD_CTX_BA_ATTR_BUFF_SIZE,
+	NL80211_SMD_CTX_BA_ATTR_POLICY,
+	NL80211_SMD_CTX_BA_ATTR_AMSDU_SUPPORT,
+	NL80211_SMD_CTX_BA_ATTR_TIMEOUT,
+	NL80211_SMD_CTX_BA_ATTR_EXT_NO_FRAG,
+	NL80211_SMD_CTX_BA_ATTR_EXT_FRAG_LEVEL,
+	NL80211_SMD_CTX_BA_ATTR_EXT_BUFF_SIZE,
+	NL80211_SMD_CTX_BA_ATTR_WINSTARTO,
+
+	__NL80211_SMD_CTX_BA_ATTR_LAST,
+	NL80211_SMD_CTX_BA_ATTR_MAX = __NL80211_SMD_CTX_BA_ATTR_LAST - 1
+};
+
+/**
+ * enum nl80211_smd_ctx_dl - SMD Dynamic Context - DL direction
+ *
+ * @__NL80211_SMD_CTX_DL_ATTR_INVALID: Invalid attribute.
+ * @NL80211_SMD_CTX_DL_ATTR_VALID_TID_BITMAP: Optional (u8) TIDs included.
+ * @NL80211_SMD_CTX_DL_ATTR_SN: Optional (nested) next SN (u16) per TID to
+ *	be assigned to DL individually addressed frames.
+ * @NL80211_SMD_CTX_DL_ATTR_PN: Optional (binary) starting PN (max 16 bytes) for
+ *	DL individually addressed frames.
+ * @NL80211_SMD_CTX_DL_ATTR_BA_PARAMS: Optional (nested) Block Ack parameters,
+ *	nested array of TIDs (uses &enum nl80211_smd_ctx_ba_param).
+ * @NL80211_SMD_CTX_DL_ATTR_MGMT_SN: Optional (u16) next SN to be assigned for
+ *	DL individually addressed management frames.
+ * @NL80211_SMD_CTX_DL_ATTR_MGMT_PN: Optional (binary) starting PN
+ *	(max 16 bytes) for DL individually addressed management frames.
+ * @__NL80211_SMD_CTX_DL_ATTR_LAST: Last attribute, used internally.
+ * @NL80211_SMD_CTX_DL_ATTR_MAX: Max attribute.
+ *
+ * Used with %NL80211_SMD_CTX_ATTR_DL.
+ */
+enum nl80211_smd_ctx_dl {
+	__NL80211_SMD_CTX_DL_ATTR_INVALID,
+	NL80211_SMD_CTX_DL_ATTR_VALID_TID_BITMAP,
+	NL80211_SMD_CTX_DL_ATTR_SN,
+	NL80211_SMD_CTX_DL_ATTR_PN,
+	NL80211_SMD_CTX_DL_ATTR_BA_PARAMS,
+	NL80211_SMD_CTX_DL_ATTR_MGMT_SN,
+	NL80211_SMD_CTX_DL_ATTR_MGMT_PN,
+
+	__NL80211_SMD_CTX_DL_ATTR_LAST,
+	NL80211_SMD_CTX_DL_ATTR_MAX = __NL80211_SMD_CTX_DL_ATTR_LAST - 1
+};
+
+/**
+ * enum nl80211_smd_ctx_ul - SMD Dynamic Context - UL direction
+ *
+ * @__NL80211_SMD_CTX_UL_ATTR_INVALID: Invalid attribute.
+ * @NL80211_SMD_CTX_UL_ATTR_VALID_TID_BITMAP: Optional (u8) TIDs included.
+ * @NL80211_SMD_CTX_UL_ATTR_SN: Optional (nested) last SN received per TID
+ *	for UL individually addressed frames.
+ * @NL80211_SMD_CTX_UL_ATTR_PN: Optional (nested) last PN received per TID
+ *	for UL individually addressed frames.
+ * @NL80211_SMD_CTX_UL_ATTR_BA_PARAMS: Optional (nested) Block Ack parameters
+ *	(uses &enum nl80211_smd_ctx_ba_param).
+ * @NL80211_SMD_CTX_UL_ATTR_MGMT_SN: Optional (u16) last SN received for
+ *	UL individually addressed management frames.
+ * @NL80211_SMD_CTX_UL_ATTR_MGMT_PN: Optional (binary, max 16 bytes) last PN
+ *	received for UL individually addressed management frames.
+ * @__NL80211_SMD_CTX_UL_ATTR_LAST: Last attribute, used internally.
+ * @NL80211_SMD_CTX_UL_ATTR_MAX: Max attribute.
+ *
+ * Used with %NL80211_SMD_CTX_ATTR_UL.
+ */
+enum nl80211_smd_ctx_ul {
+	__NL80211_SMD_CTX_UL_ATTR_INVALID,
+	NL80211_SMD_CTX_UL_ATTR_VALID_TID_BITMAP,
+	NL80211_SMD_CTX_UL_ATTR_SN,
+	NL80211_SMD_CTX_UL_ATTR_PN,
+	NL80211_SMD_CTX_UL_ATTR_BA_PARAMS,
+	NL80211_SMD_CTX_UL_ATTR_MGMT_SN,
+	NL80211_SMD_CTX_UL_ATTR_MGMT_PN,
+
+	__NL80211_SMD_CTX_UL_ATTR_LAST,
+	NL80211_SMD_CTX_UL_ATTR_MAX = __NL80211_SMD_CTX_UL_ATTR_LAST - 1
+};
+
+/**
+ * enum nl80211_smd_ctx - SMD Context information
+ *
+ * Top-level container for SMD BSS Transition dynamic context.  Carried in
+ * %NL80211_ATTR_SMD_CTX with %NL80211_CMD_SET_SMD_CTX (target AP MLD) or
+ * with %NL80211_CMD_FRAME (current AP MLD reporting context to userspace)
+ * and %NL80211_CMD_SMD_CTX_EVENT (current AP MLD reporting the requested
+ * context on behalf of the target AP MLD).
+ *
+ * @__NL80211_SMD_CTX_ATTR_INVALID: Invalid attribute.
+ * @NL80211_SMD_CTX_ATTR_DL: Optional (nested) DL parameters.
+ *	See &enum nl80211_smd_ctx_dl.
+ * @NL80211_SMD_CTX_ATTR_UL: Optional (nested) UL parameters.
+ *	See &enum nl80211_smd_ctx_ul.
+ * @__NL80211_SMD_CTX_ATTR_LAST: Last attribute, used internally.
+ * @NL80211_SMD_CTX_ATTR_MAX: Max attribute.
+ */
+enum nl80211_smd_ctx {
+	__NL80211_SMD_CTX_ATTR_INVALID,
+	NL80211_SMD_CTX_ATTR_DL,
+	NL80211_SMD_CTX_ATTR_UL,
+
+	__NL80211_SMD_CTX_ATTR_LAST,
+	NL80211_SMD_CTX_ATTR_MAX = __NL80211_SMD_CTX_ATTR_LAST - 1
+};
+
 #endif /* __LINUX_NL80211_H */
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 5df145ab4ab1..d2cd03d8b0c5 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -789,6 +789,51 @@ nl80211_nan_conf_policy[NL80211_NAN_CONF_ATTR_MAX + 1] = {
 	[NL80211_NAN_CONF_INSTANT_COMM] = { .type = NLA_FLAG },
 };
 
+static const struct nla_policy
+nl80211_smd_ctx_ba_policy[NL80211_SMD_CTX_BA_ATTR_MAX + 1] = {
+	[NL80211_SMD_CTX_BA_ATTR_BUFF_SIZE] = { .type = NLA_U16 },
+	[NL80211_SMD_CTX_BA_ATTR_POLICY] = { .type = NLA_U8 },
+	[NL80211_SMD_CTX_BA_ATTR_AMSDU_SUPPORT] = { .type = NLA_FLAG },
+	[NL80211_SMD_CTX_BA_ATTR_TIMEOUT] = { .type = NLA_U16 },
+	[NL80211_SMD_CTX_BA_ATTR_EXT_NO_FRAG] = { .type = NLA_FLAG },
+	[NL80211_SMD_CTX_BA_ATTR_EXT_FRAG_LEVEL] = { .type = NLA_U8 },
+	[NL80211_SMD_CTX_BA_ATTR_EXT_BUFF_SIZE] = { .type = NLA_U16 },
+	[NL80211_SMD_CTX_BA_ATTR_WINSTARTO] = { .type = NLA_U16 },
+};
+
+static const struct nla_policy
+nl80211_smd_ctx_dl_policy[NL80211_SMD_CTX_DL_ATTR_MAX + 1] = {
+	[NL80211_SMD_CTX_DL_ATTR_VALID_TID_BITMAP] = { .type = NLA_U8 },
+	[NL80211_SMD_CTX_DL_ATTR_SN] = { .type = NLA_NESTED },
+	[NL80211_SMD_CTX_DL_ATTR_PN] = { .type = NLA_BINARY,
+					 .len = IEEE80211_SMD_CTX_MAX_PN_LEN },
+	[NL80211_SMD_CTX_DL_ATTR_BA_PARAMS] =
+		NLA_POLICY_NESTED_ARRAY(nl80211_smd_ctx_ba_policy),
+	[NL80211_SMD_CTX_DL_ATTR_MGMT_SN] = { .type = NLA_U16 },
+};
+
+static const struct nla_policy
+nl80211_smd_ctx_ul_policy[NL80211_SMD_CTX_UL_ATTR_MAX + 1] = {
+	[NL80211_SMD_CTX_UL_ATTR_VALID_TID_BITMAP] = { .type = NLA_U8 },
+	[NL80211_SMD_CTX_UL_ATTR_SN] = { .type = NLA_NESTED },
+	[NL80211_SMD_CTX_UL_ATTR_PN] = { .type = NLA_NESTED },
+	[NL80211_SMD_CTX_UL_ATTR_BA_PARAMS] =
+		NLA_POLICY_NESTED_ARRAY(nl80211_smd_ctx_ba_policy),
+	[NL80211_SMD_CTX_UL_ATTR_MGMT_SN] = { .type = NLA_U16 },
+	[NL80211_SMD_CTX_UL_ATTR_MGMT_PN] = {
+		.type = NLA_BINARY,
+		.len = IEEE80211_SMD_CTX_MAX_PN_LEN
+	},
+};
+
+static const struct nla_policy
+nl80211_smd_ctx_policy[NL80211_SMD_CTX_ATTR_MAX + 1] = {
+	[NL80211_SMD_CTX_ATTR_DL] =
+		NLA_POLICY_NESTED(nl80211_smd_ctx_dl_policy),
+	[NL80211_SMD_CTX_ATTR_UL] =
+		NLA_POLICY_NESTED(nl80211_smd_ctx_ul_policy),
+};
+
 static const struct netlink_range_validation nl80211_punct_bitmap_range = {
 	.min = 0,
 	.max = 0xffff,
@@ -1203,6 +1248,9 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
 	[NL80211_ATTR_ASSOC_PROTECTED_TWT] = { .type = NLA_FLAG },
 	[NL80211_ATTR_SMD_SUPPORT] = { .type = NLA_FLAG },
 	[NL80211_ATTR_SMD_ROAM_STA] = { .type = NLA_FLAG },
+	[NL80211_ATTR_SMD_CTX] = NLA_POLICY_NESTED(nl80211_smd_ctx_policy),
+	[NL80211_ATTR_SMD_CTX_TYPE] =
+		NLA_POLICY_MAX(NLA_U8, NL80211_SMD_CTX_TYPE_MAX),
 };
 
 /* policy for the key attributes */

-- 
2.34.1