2019-11-11 12:00:59

by Aurelien Jarno

Subject: [PATCH BlueZ] mesh: fix node default TTL

There is a confusion between the node default TTL (section 4.2.7) and
the publish TTL (section 4.2.2.5):

- The node default TTL can only take values 0x00, and 0x02 to 0x7f. The
value 0xff is not prohibited.
- The publish TTL can take values 0x00 to 0x7f, as well as 0xff which
means use the node default TTL.

Currently the default node TTL is set to 0xff (DEFAULT_TTL), and
read_default_ttl() also allows such a value. This patch fixes that to
use 0x7f (TTL_MASK) as the default value instead.

Note that the code handling OP_CONFIG_DEFAULT_TTL_SET correctly use 0x7f
(TTL_MASK) for the upper allowed limit.
---
mesh/mesh-config-json.c | 2 +-
mesh/node.c | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/mesh/mesh-config-json.c b/mesh/mesh-config-json.c
index b2cff6824..5ca2961b0 100644
--- a/mesh/mesh-config-json.c
+++ b/mesh/mesh-config-json.c
@@ -358,7 +358,7 @@ static bool read_default_ttl(json_object *jobj, uint8_t *ttl)
if (!val && errno == EINVAL)
return false;

- if (val < 0 || val == 1 || val > DEFAULT_TTL)
+ if (val < 0 || val == 1 || val > TTL_MASK)
return false;

*ttl = (uint8_t) val;
diff --git a/mesh/node.c b/mesh/node.c
index e23f32dd1..5dcffe6f7 100644
--- a/mesh/node.c
+++ b/mesh/node.c
@@ -672,7 +672,7 @@ struct l_queue *node_get_element_models(struct mesh_node *node,
uint8_t node_default_ttl_get(struct mesh_node *node)
{
if (!node)
- return DEFAULT_TTL;
+ return TTL_MASK;
return node->ttl;
}

@@ -1352,7 +1352,7 @@ static void set_defaults(struct mesh_node *node)
node->friend = MESH_MODE_UNSUPPORTED;
node->beacon = MESH_MODE_DISABLED;
node->relay.mode = MESH_MODE_DISABLED;
- node->ttl = DEFAULT_TTL;
+ node->ttl = TTL_MASK;
node->seq_number = DEFAULT_SEQUENCE_NUMBER;

/* Add configuration server model on primary element */
--
2.24.0

2019-11-19 23:54:47

by Gix, Brian

Subject: Re: [PATCH BlueZ] mesh: fix node default TTL

Applied, Thanks

On Mon, 2019-11-11 at 13:00 +0100, Aurelien Jarno wrote:
> There is a confusion between the node default TTL (section 4.2.7) and
> the publish TTL (section 4.2.2.5):
>
> - The node default TTL can only take values 0x00, and 0x02 to 0x7f. The
> value 0xff is not prohibited.
> - The publish TTL can take values 0x00 to 0x7f, as well as 0xff which
> means use the node default TTL.
>
> Currently the default node TTL is set to 0xff (DEFAULT_TTL), and
> read_default_ttl() also allows such a value. This patch fixes that to
> use 0x7f (TTL_MASK) as the default value instead.
>
> Note that the code handling OP_CONFIG_DEFAULT_TTL_SET correctly use 0x7f
> (TTL_MASK) for the upper allowed limit.
> ---
> mesh/mesh-config-json.c | 2 +-
> mesh/node.c | 4 ++--
> 2 files changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/mesh/mesh-config-json.c b/mesh/mesh-config-json.c
> index b2cff6824..5ca2961b0 100644
> --- a/mesh/mesh-config-json.c
> +++ b/mesh/mesh-config-json.c
> @@ -358,7 +358,7 @@ static bool read_default_ttl(json_object *jobj, uint8_t *ttl)
> if (!val && errno == EINVAL)
> return false;
>
> - if (val < 0 || val == 1 || val > DEFAULT_TTL)
> + if (val < 0 || val == 1 || val > TTL_MASK)
> return false;
>
> *ttl = (uint8_t) val;
> diff --git a/mesh/node.c b/mesh/node.c
> index e23f32dd1..5dcffe6f7 100644
> --- a/mesh/node.c
> +++ b/mesh/node.c
> @@ -672,7 +672,7 @@ struct l_queue *node_get_element_models(struct mesh_node *node,
> uint8_t node_default_ttl_get(struct mesh_node *node)
> {
> if (!node)
> - return DEFAULT_TTL;
> + return TTL_MASK;
> return node->ttl;
> }
>
> @@ -1352,7 +1352,7 @@ static void set_defaults(struct mesh_node *node)
> node->friend = MESH_MODE_UNSUPPORTED;
> node->beacon = MESH_MODE_DISABLED;
> node->relay.mode = MESH_MODE_DISABLED;
> - node->ttl = DEFAULT_TTL;
> + node->ttl = TTL_MASK;
> node->seq_number = DEFAULT_SEQUENCE_NUMBER;
>
> /* Add configuration server model on primary element */