2020-04-22 01:04:34

by Miao-chen Chou

[permalink] [raw]
Subject: [BlueZ PATCH v2] doc: Describe the new Advertisement Monitor support

This describes the following commands.
- Add Advertisement Patterns Monitor
- Remove Advertisement Monitors
Note that the content of a monitor can differ based on its type. For now we
introduce only pattern-based monitor, so you may find that unlike the
command of removing monitor(s), the Add command is tied to a specific type.
---

Changes in v2:
- Combine commands to remove one monitor and remove all monitors. The
refined command takes multiple handles and an extra field to indicate
whether to remove all monitors.

doc/mgmt-api.txt | 83 ++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 83 insertions(+)

diff --git a/doc/mgmt-api.txt b/doc/mgmt-api.txt
index 39f23c456..d5d402361 100644
--- a/doc/mgmt-api.txt
+++ b/doc/mgmt-api.txt
@@ -3138,6 +3138,89 @@ Read Security Information Command
Invalid Index


+Add Advertisement Patterns Monitor Command
+=========================================
+
+ Command Code: 0x0049
+ Controller Index: <controller id>
+ Command Parameters: Pattern_count (1 Octets)
+ Pattern1 {
+ AD_Data_Type (1 Octet)
+ Offset (1 Octet)
+ Length (1 Octet)
+ Value (variable length)
+ }
+ Pattern2 { }
+ ...
+ Return Parameters: Monitor_Handle (8 Octets)
+
+ This command is used to add an advertisement monitor whose filtering
+ conditions are patterns. The kernel would track the number of registered
+ monitors to determine whether to perform LE scanning while there is
+ ongoing LE scanning for other intentions, such as auto-reconnection and
+ discovery session. If the controller supports Microsoft HCI extension,
+ the kernel would offload the content filtering to the controller in
+ order to reduce power consumption; otherwise the kernel ignore the
+ content of the monitor. Note that if the there are more than one
+ patterns, OR logic would applied among patterns during filtering. In
+ other words, any advertisement matching at least one pattern in a given
+ monitor would be considered as a match.
+
+ A pattern contain the following fields.
+ AD_Data_Type Advertising Data Type. The possible values are
+ defined in Core Specification Supplement.
+ Offset The start index where pattern matching shall be
+ performed with in the AD data.
+ Length The length of the pattern value in bytes.
+ Value The value of the pattern in bytes.
+
+ Here is an example of a pattern.
+ {
+ 0x16, // Service Data - 16-bit UUID
+ 0x02, // Skip the UUID part.
+ 0x04,
+ {0x11, 0x22, 0x33, 0x44},
+ }
+
+ Possible errors: Failed
+ Busy
+ Invalid Parameters
+
+
+Remove Advertisement Monitors Command
+=====================================
+
+ Command Code: 0x004A
+ Controller Index: <controller id>
+ Command Parameters: Remove_All (1 Octet)
+ Monitor_Count (2 Octets)
+ Monitor_Handle[i] (8 Octets)
+ Return Parameters: Removed_Monitor_Count (2 Octets)
+ Removed_Monitor_Handle[i] (8 Octets)
+
+ This command is used to remove advertisement monitor(s). The kernel
+ would remove the monitor(s) with Monitor_Index and update the LE
+ scanning. If the controller supports Microsoft HCI extension and the
+ monitor(s) has been offloaded, the kernel would cancel the offloading;
+ otherwise the kernel takes no further actions other than removing the
+ monitor(s) from the list.
+
+ Remove_All can be the following values.
+ Value Operation
+ -------------------------
+ 0x00 Removes only the monitors with handles specified
+ in Monitor_Handle[i], so there must be at least
+ one handle.
+ 0x01 Removes all existing monitor(s), so
+ Monitor_Count must be 0, and Monitor_Handle
+ must be empty.
+
+ Possible errors: Failed
+ Busy
+ Invalid Index
+ Invalid Parameters
+
+
Command Complete Event
======================

--
2.24.1


2020-04-22 17:34:41

by Marcel Holtmann

[permalink] [raw]
Subject: Re: [BlueZ PATCH v2] doc: Describe the new Advertisement Monitor support

Hi Miao-chen,

> This describes the following commands.
> - Add Advertisement Patterns Monitor
> - Remove Advertisement Monitors
> Note that the content of a monitor can differ based on its type. For now we
> introduce only pattern-based monitor, so you may find that unlike the
> command of removing monitor(s), the Add command is tied to a specific type.
> ---
>
> Changes in v2:
> - Combine commands to remove one monitor and remove all monitors. The
> refined command takes multiple handles and an extra field to indicate
> whether to remove all monitors.
>
> doc/mgmt-api.txt | 83 ++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 83 insertions(+)
>
> diff --git a/doc/mgmt-api.txt b/doc/mgmt-api.txt
> index 39f23c456..d5d402361 100644
> --- a/doc/mgmt-api.txt
> +++ b/doc/mgmt-api.txt
> @@ -3138,6 +3138,89 @@ Read Security Information Command
> Invalid Index
>
>
> +Add Advertisement Patterns Monitor Command
> +=========================================

I wonder if we do Add Advertisement Monitor Pattern or Add Advertisement Monitor With Pattern.

> +
> + Command Code: 0x0049
> + Controller Index: <controller id>
> + Command Parameters: Pattern_count (1 Octets)
> + Pattern1 {
> + AD_Data_Type (1 Octet)
> + Offset (1 Octet)
> + Length (1 Octet)
> + Value (variable length)
> + }
> + Pattern2 { }
> + ...
> + Return Parameters: Monitor_Handle (8 Octets)

Why 8 Octets? How many do you expect? I would do 16-bit.

> +
> + This command is used to add an advertisement monitor whose filtering
> + conditions are patterns. The kernel would track the number of registered
> + monitors to determine whether to perform LE scanning while there is
> + ongoing LE scanning for other intentions, such as auto-reconnection and
> + discovery session. If the controller supports Microsoft HCI extension,
> + the kernel would offload the content filtering to the controller in
> + order to reduce power consumption; otherwise the kernel ignore the
> + content of the monitor. Note that if the there are more than one
> + patterns, OR logic would applied among patterns during filtering. In
> + other words, any advertisement matching at least one pattern in a given
> + monitor would be considered as a match.
> +
> + A pattern contain the following fields.
> + AD_Data_Type Advertising Data Type. The possible values are
> + defined in Core Specification Supplement.
> + Offset The start index where pattern matching shall be
> + performed with in the AD data.
> + Length The length of the pattern value in bytes.
> + Value The value of the pattern in bytes.
> +
> + Here is an example of a pattern.
> + {
> + 0x16, // Service Data - 16-bit UUID
> + 0x02, // Skip the UUID part.
> + 0x04,
> + {0x11, 0x22, 0x33, 0x44},
> + }
> +
> + Possible errors: Failed
> + Busy
> + Invalid Parameters
> +
> +
> +Remove Advertisement Monitors Command
> +=====================================

I would have a generic Remove Adveristement Monitor

> +
> + Command Code: 0x004A
> + Controller Index: <controller id>
> + Command Parameters: Remove_All (1 Octet)

Skip the Remove_All. If you give Monitor_Count == 0, then it will remove all of them. This is how we have done the others.

> + Monitor_Count (2 Octets)
> + Monitor_Handle[i] (8 Octets)
> + Return Parameters: Removed_Monitor_Count (2 Octets)
> + Removed_Monitor_Handle[i] (8 Octets)

Return values are not needed here.

> +
> + This command is used to remove advertisement monitor(s). The kernel
> + would remove the monitor(s) with Monitor_Index and update the LE
> + scanning. If the controller supports Microsoft HCI extension and the
> + monitor(s) has been offloaded, the kernel would cancel the offloading;
> + otherwise the kernel takes no further actions other than removing the
> + monitor(s) from the list.
> +
> + Remove_All can be the following values.
> + Value Operation
> + -------------------------
> + 0x00 Removes only the monitors with handles specified
> + in Monitor_Handle[i], so there must be at least
> + one handle.
> + 0x01 Removes all existing monitor(s), so
> + Monitor_Count must be 0, and Monitor_Handle
> + must be empty.
> +
> + Possible errors: Failed
> + Busy
> + Invalid Index
> + Invalid Parameters
> +
> +
> Command Complete Event
> ======================

You are missing signals for Monitor Added and Monitor Removed.

And we are also missing a command for reading the basic supported features. Like we do for Advertising as well.

Regards

Marcel

2020-04-23 01:14:49

by Miao-chen Chou

[permalink] [raw]
Subject: Re: [BlueZ PATCH v2] doc: Describe the new Advertisement Monitor support

Hi Marcel,

On Wed, Apr 22, 2020 at 10:33 AM Marcel Holtmann <[email protected]> wrote:
>
> Hi Miao-chen,
>
> > This describes the following commands.
> > - Add Advertisement Patterns Monitor
> > - Remove Advertisement Monitors
> > Note that the content of a monitor can differ based on its type. For now we
> > introduce only pattern-based monitor, so you may find that unlike the
> > command of removing monitor(s), the Add command is tied to a specific type.
> > ---
> >
> > Changes in v2:
> > - Combine commands to remove one monitor and remove all monitors. The
> > refined command takes multiple handles and an extra field to indicate
> > whether to remove all monitors.
> >
> > doc/mgmt-api.txt | 83 ++++++++++++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 83 insertions(+)
> >
> > diff --git a/doc/mgmt-api.txt b/doc/mgmt-api.txt
> > index 39f23c456..d5d402361 100644
> > --- a/doc/mgmt-api.txt
> > +++ b/doc/mgmt-api.txt
> > @@ -3138,6 +3138,89 @@ Read Security Information Command
> > Invalid Index
> >
> >
> > +Add Advertisement Patterns Monitor Command
> > +=========================================
>
> I wonder if we do Add Advertisement Monitor Pattern or Add Advertisement Monitor With Pattern.
>
> > +
> > + Command Code: 0x0049
> > + Controller Index: <controller id>
> > + Command Parameters: Pattern_count (1 Octets)
> > + Pattern1 {
> > + AD_Data_Type (1 Octet)
> > + Offset (1 Octet)
> > + Length (1 Octet)
> > + Value (variable length)
> > + }
> > + Pattern2 { }
> > + ...
> > + Return Parameters: Monitor_Handle (8 Octets)
>
> Why 8 Octets? How many do you expect? I would do 16-bit.
My thought was that the number of monitor slots may not be fixed for
different extensions, so the idea was to have one-time handles which
will not be reused once a monitor was removed. If reusing the slots is
a preferable approach, given that Android and Microsoft extensions use
uint8 for indexing filters, we can use either uint16 or uint32 as the
index. I will put uint16 for now.
>
> > +
> > + This command is used to add an advertisement monitor whose filtering
> > + conditions are patterns. The kernel would track the number of registered
> > + monitors to determine whether to perform LE scanning while there is
> > + ongoing LE scanning for other intentions, such as auto-reconnection and
> > + discovery session. If the controller supports Microsoft HCI extension,
> > + the kernel would offload the content filtering to the controller in
> > + order to reduce power consumption; otherwise the kernel ignore the
> > + content of the monitor. Note that if the there are more than one
> > + patterns, OR logic would applied among patterns during filtering. In
> > + other words, any advertisement matching at least one pattern in a given
> > + monitor would be considered as a match.
> > +
> > + A pattern contain the following fields.
> > + AD_Data_Type Advertising Data Type. The possible values are
> > + defined in Core Specification Supplement.
> > + Offset The start index where pattern matching shall be
> > + performed with in the AD data.
> > + Length The length of the pattern value in bytes.
> > + Value The value of the pattern in bytes.
> > +
> > + Here is an example of a pattern.
> > + {
> > + 0x16, // Service Data - 16-bit UUID
> > + 0x02, // Skip the UUID part.
> > + 0x04,
> > + {0x11, 0x22, 0x33, 0x44},
> > + }
> > +
> > + Possible errors: Failed
> > + Busy
> > + Invalid Parameters
> > +
> > +
> > +Remove Advertisement Monitors Command
> > +=====================================
>
> I would have a generic Remove Adveristement Monitor. As requested, I will combine the remove and remove all operations by reserving 0 as a hint for removing all.
>
> > +
> > + Command Code: 0x004A
> > + Controller Index: <controller id>
> > + Command Parameters: Remove_All (1 Octet)
>
> Skip the Remove_All. If you give Monitor_Count == 0, then it will remove all of them. This is how we have done the others.
>
> > + Monitor_Count (2 Octets)
> > + Monitor_Handle[i] (8 Octets)
> > + Return Parameters: Removed_Monitor_Count (2 Octets)
> > + Removed_Monitor_Handle[i] (8 Octets)
>
> Return values are not needed here.
>
> > +
> > + This command is used to remove advertisement monitor(s). The kernel
> > + would remove the monitor(s) with Monitor_Index and update the LE
> > + scanning. If the controller supports Microsoft HCI extension and the
> > + monitor(s) has been offloaded, the kernel would cancel the offloading;
> > + otherwise the kernel takes no further actions other than removing the
> > + monitor(s) from the list.
> > +
> > + Remove_All can be the following values.
> > + Value Operation
> > + -------------------------
> > + 0x00 Removes only the monitors with handles specified
> > + in Monitor_Handle[i], so there must be at least
> > + one handle.
> > + 0x01 Removes all existing monitor(s), so
> > + Monitor_Count must be 0, and Monitor_Handle
> > + must be empty.
> > +
> > + Possible errors: Failed
> > + Busy
> > + Invalid Index
> > + Invalid Parameters
> > +
> > +
> > Command Complete Event
> > ======================
>
> You are missing signals for Monitor Added and Monitor Removed.
Nice catch. I will add them in v3.
>
> And we are also missing a command for reading the basic supported features. Like we do for Advertising as well.
There was a comment made in the past discussion where we can introduce
a new setting(s) in the returned supported_settings of
MGMT_OP_READ_INFO command to indicate the features such as
MGMT_SETTING_HW_FILTERING . But given that there can be multiple
extensions, it may be preferable to have a separate command which
should be extendable.

Thanks,
Miao