Add Bridge Endpoint Support

* Update peer structure to accomodate for Bridge Type Endpoints.
* New Dbus argument in AssignStaticEndpoint dbus method to consider
bridge/pool start eid.
* update existing pytest methods to account for new signature of
  AssignEndpointStatic dbus method for pool start eid

Signed-off-by: Faizan Ali <faizana@nvidia.com>

Author: faizana-nvidia

docs/mctpd.md

@@ -123,16 +123,18 @@ Similar to SetupEndpoint, but will always assign an EID rather than querying for
 existing ones. Will return `new = false` when an endpoint is already known to
 `mctpd`.
 
-#### `.AssignEndpointStatic`: `ayy` → `yisb`
+#### `.AssignEndpointStatic`: `ayyy` → `yisb`
 
 Similar to AssignEndpoint, but takes an additional EID argument:
 
 ```
-AssignEndpointStatic <hwaddr> <static-EID>
+AssignEndpointStatic <hwaddr> <static-EID> <pool_start-EID>
 ```
 
 to assign `<static-EID>` to the endpoint with hardware address `hwaddr`.
 
+For MCTP Bridges `<pool_start-EID>` will be starting eid assigned for downstream devices. For non-bridge devices this argument value will be zero.
+
 This call will fail if the endpoint already has an EID, and that EID is
 different from `static-EID`, or if `static-EID` is already assigned to another
 endpoint.

src/mctpd.c

@@ -177,6 +177,11 @@ struct peer {
 		uint8_t endpoint_type;
 		uint8_t medium_spec;
 	} recovery;
+
+	// Pool size
+	uint8_t pool_size;
+	uint8_t pool_start;
+
 };
 typedef struct peer peer;
 
@@ -1313,7 +1318,7 @@ static int endpoint_query_phys(ctx *ctx, const dest_phys *dest,
 }
 
 /* returns -ECONNREFUSED if the endpoint returns failure. */
-static int endpoint_send_set_endpoint_id(const peer *peer, mctp_eid_t *new_eid)
+static int endpoint_send_set_endpoint_id(peer *peer, mctp_eid_t *new_eid)
 {
 	struct sockaddr_mctp_ext addr;
 	struct mctp_ctrl_cmd_set_eid req = {0};
@@ -1360,9 +1365,11 @@ static int endpoint_send_set_endpoint_id(const peer *peer, mctp_eid_t *new_eid)
 
 	alloc = resp->status & 0x3;
 	if (alloc != 0) {
-		// TODO for bridges
-		warnx("%s requested allocation pool, unimplemented",
-			dest_phys_tostr(dest));
+		peer->pool_size = resp->eid_pool_size;
+		if (peer->ctx->verbose) {
+			warnx("%s requested allocation of pool size = %d",
+				dest_phys_tostr(dest), peer->pool_size);
+		}
 	}
 
 	rc = 0;
@@ -2114,7 +2121,7 @@ static int method_assign_endpoint_static(sd_bus_message *call, void *data,
 	char *peer_path = NULL;
 	peer *peer = NULL;
 	ctx *ctx = data;
-	uint8_t eid;
+	uint8_t eid, start_eid;
 	int rc;
 
 	dest->ifindex = interface_call_to_ifindex_busowner(ctx, call);
@@ -2130,6 +2137,10 @@ static int method_assign_endpoint_static(sd_bus_message *call, void *data,
 	if (rc < 0)
 		goto err;
 
+	rc = sd_bus_message_read(call, "y", &start_eid);
+	if (rc < 0)
+		goto err;
+
 	rc = validate_dest_phys(ctx, dest);
 	if (rc < 0)
 		return sd_bus_error_setf(berr, SD_BUS_ERROR_INVALID_ARGS,
@@ -2173,6 +2184,11 @@ static int method_assign_endpoint_static(sd_bus_message *call, void *data,
 	}
 	dfree(peer_path);
 
+	/* MCTP Bridge Support */
+	if(peer->pool_size > 0) {
+		peer->pool_start = start_eid;
+	}
+
 	return sd_bus_reply_method_return(call, "yisb",
 		peer->eid, peer->net, peer_path, 1);
 err:
@@ -2852,9 +2868,10 @@ static const sd_bus_vtable bus_owner_vtable[] = {
 		0),
 
 	SD_BUS_METHOD_WITH_NAMES("AssignEndpointStatic",
-		"ayy",
+		"ayyy",
 		SD_BUS_PARAM(physaddr)
-		SD_BUS_PARAM(eid),
+		SD_BUS_PARAM(eid)
+		SD_BUS_PARAM(start_eid),
 		"yisb",
 		SD_BUS_PARAM(eid)
 		SD_BUS_PARAM(net)

tests/conftest.py

@@ -248,12 +248,13 @@ def to_buf(self):
         return bytes([flags, self.cmd]) + self.data
 
 class Endpoint:
-    def __init__(self, iface, lladdr, ep_uuid = None, eid = 0, types = None):
+    def __init__(self, iface, lladdr, ep_uuid = None, eid = 0, types = None, pool_size = 0):
         self.iface = iface
         self.lladdr = lladdr
         self.uuid = ep_uuid or uuid.uuid1()
         self.eid = eid
         self.types = types or [0]
+        self.pool_size = pool_size
         # keyed by (type, type-specific-instance)
         self.commands = {}
 
@@ -291,6 +292,10 @@ async def handle_mctp_control(self, sock, addr, data):
                 (op, eid) = data[2:]
                 self.eid = eid
                 data = bytes(hdr + [0x00, 0x00, self.eid, 0x00])
+                if (self.pool_size):
+                    data = bytes(hdr + [0x00, 0x01, self.eid, self.pool_size])
+                else:
+                    data = bytes(hdr + [0x00, 0x00, self.eid, 0x00])
                 await sock.send(raddr, data)
 
             elif opcode == 2:

tests/test_mctpd.py

@@ -287,10 +287,12 @@ async def test_assign_endpoint_static(dbus, mctpd):
     dev = mctpd.network.endpoints[0]
     mctp = await mctpd_mctp_iface_obj(dbus, iface)
     static_eid = 12
+    start_eid = 0
 
     (eid, _, _, new) = await mctp.call_assign_endpoint_static(
         dev.lladdr,
-        static_eid
+        static_eid,
+        start_eid
     )
 
     assert eid == static_eid
@@ -309,10 +311,12 @@ async def test_assign_endpoint_static_allocated(dbus, mctpd):
     mctp = await mctpd_mctp_iface_obj(dbus, iface)
     dev = mctpd.network.endpoints[0]
     static_eid = 12
+    start_eid = 0
 
     (eid, _, _, new) = await mctp.call_assign_endpoint_static(
         dev.lladdr,
         static_eid,
+        start_eid
     )
 
     assert eid == static_eid
@@ -322,6 +326,7 @@ async def test_assign_endpoint_static_allocated(dbus, mctpd):
     (eid, _, _, new) = await mctp.call_assign_endpoint_static(
         dev.lladdr,
         static_eid,
+        start_eid
     )
 
     assert eid == static_eid
@@ -345,7 +350,7 @@ async def test_assign_endpoint_static_conflict(dbus, mctpd):
 
     # try to assign dev2 with the dev1's existing EID
     with pytest.raises(asyncdbus.errors.DBusError) as ex:
-        await mctp.call_assign_endpoint_static(dev2.lladdr, eid)
+        await mctp.call_assign_endpoint_static(dev2.lladdr, eid, 0)
 
     assert str(ex.value) == "Address in use"
 
@@ -356,17 +361,19 @@ async def test_assign_endpoint_static_varies(dbus, mctpd):
     dev = mctpd.network.endpoints[0]
     mctp = await mctpd_mctp_iface_obj(dbus, iface)
     static_eid = 12
+    start_eid = 0
 
     (eid, _, _, new) = await mctp.call_assign_endpoint_static(
         dev.lladdr,
-        static_eid
+        static_eid,
+        start_eid
     )
 
     assert eid == static_eid
     assert new
 
     with pytest.raises(asyncdbus.errors.DBusError) as ex:
-        await mctp.call_assign_endpoint_static(dev.lladdr, 13)
+        await mctp.call_assign_endpoint_static(dev.lladdr, 13, 0)
 
     assert str(ex.value) == "Already assigned a different EID"