babeld: add rxcost to the ubus add_interface function

Allow to set rxcosts when adding an interface via ubus add_interface
function. Example:

  ubus call babeld add_interface '{"ifname":"eth0", "rxcost":1024}'

Signed-off-by: Nick Hainke <vincent@systemli.org>

babeld/patches/000-put-add_ifcon-to-configuration-h.patch

@@ -0,0 +1,50 @@
+From 23d4e0d8fdd69caa1644c88dc8e6518edb7fb5b5 Mon Sep 17 00:00:00 2001
+From: Nick Hainke <vincent@systemli.org>
+Date: Fri, 25 Mar 2022 14:08:58 +0100
+Subject: [PATCH] Put add_ifcon to configuration.h
+
+If you want to add an interface with a different config you need to call
+add_interface with an interface_conf as an argument. add_interface is
+already located in the configuration.h. However, add_ifconf is not
+available. The commit puts add_ifcon into the header. Further, it also
+adds interface_confs to the header. The add_ifconf requires as a
+parameter the interface_confs list.
+
+Signed-off-by: Nick Hainke <vincent@systemli.org>
+---
+ configuration.c | 4 ++--
+ configuration.h | 2 ++
+ 2 files changed, 4 insertions(+), 2 deletions(-)
+
+--- a/configuration.c
++++ b/configuration.c
+@@ -46,7 +46,7 @@ static struct filter *output_filters = N
+ static struct filter *redistribute_filters = NULL;
+ static struct filter *install_filters = NULL;
+ struct interface_conf *default_interface_conf = NULL;
+-static struct interface_conf *interface_confs = NULL;
++struct interface_conf *interface_confs = NULL;
+ 
+ /* This indicates whether initial configuration is done.  See
+    finalize_config below. */
+@@ -742,7 +742,7 @@ merge_ifconf(struct interface_conf *dest
+ #undef MERGE
+ }
+ 
+-static void
++void
+ add_ifconf(struct interface_conf *if_conf, struct interface_conf **if_confs)
+ {
+     if(*if_confs == NULL) {
+--- a/configuration.h
++++ b/configuration.h
+@@ -55,7 +55,9 @@ struct filter {
+ };
+ 
+ extern struct interface_conf *default_interface_conf;
++extern struct interface_conf *interface_confs;
+ 
++void add_ifconf(struct interface_conf *if_conf, struct interface_conf **if_confs);
+ void flush_ifconf(struct interface_conf *if_conf);
+ 
+ int parse_config_from_file(const char *filename, int *line_return);

babeld/patches/001-put-merge_ifconf-to-configuration-h.patch

@@ -0,0 +1,39 @@
+From 34b67764fd57ce63b9bbe313553471cf5539abe4 Mon Sep 17 00:00:00 2001
+From: Nick Hainke <vincent@systemli.org>
+Date: Fri, 25 Mar 2022 14:25:14 +0100
+Subject: [PATCH] Put merge_ifconf to configuration.h
+
+You want to use default_interface_conf as a basis to write an interface
+config. To do so, you write an empty interface config and use
+merge_ifconf to merge the default settings into your interface config.
+This commit puts merge_ifconf into the header.
+
+Signed-off-by: Nick Hainke <vincent@systemli.org>
+---
+ configuration.c | 2 +-
+ configuration.h | 3 +++
+ 2 files changed, 4 insertions(+), 1 deletion(-)
+
+--- a/configuration.c
++++ b/configuration.c
+@@ -709,7 +709,7 @@ add_filter(struct filter *filter, struct
+     }
+ }
+ 
+-static void
++void
+ merge_ifconf(struct interface_conf *dest,
+              const struct interface_conf *src1,
+              const struct interface_conf *src2)
+--- a/configuration.h
++++ b/configuration.h
+@@ -59,6 +59,9 @@ extern struct interface_conf *interface_
+ 
+ void add_ifconf(struct interface_conf *if_conf, struct interface_conf **if_confs);
+ void flush_ifconf(struct interface_conf *if_conf);
++void merge_ifconf(struct interface_conf *dest,
++                  const struct interface_conf *src1,
++                  const struct interface_conf *src2);
+ 
+ int parse_config_from_file(const char *filename, int *line_return);
+ int parse_config_from_string(char *string, int n, const char **message_return);

babeld/src/ubus.c

@@ -56,11 +56,12 @@ struct neighbour_list_entry {
 
 // Definition of interface function enums (to be used with ubox's blobmsg
 // helpers).
-enum { INTERFACE_IFNAME, __INTERFACE_MAX };
+enum { INTERFACE_IFNAME, INTERFACE_RXCOST, __INTERFACE_MAX };
 
 // Definition of interface parsing (to be used with ubox's blobmsg helpers).
 static const struct blobmsg_policy interface_policy[__INTERFACE_MAX] = {
     [INTERFACE_IFNAME] = {"ifname", BLOBMSG_TYPE_STRING},
+    [INTERFACE_RXCOST] = {"rxcost", BLOBMSG_TYPE_INT32},
 };
 
 // Adds an inteface (ubus equivalent to "interface"-function).
@@ -72,6 +73,7 @@ static int babeld_ubus_add_interface(struct ubus_context *ctx_local,
   struct blob_attr *tb[__INTERFACE_MAX];
   struct blob_buf b = {0};
   struct interface *ifp = NULL;
+  struct interface_conf *if_conf = NULL;
   char *ifname;
 
   blobmsg_parse(interface_policy, __INTERFACE_MAX, tb, blob_data(msg),
@@ -80,9 +82,19 @@ static int babeld_ubus_add_interface(struct ubus_context *ctx_local,
   if (!tb[INTERFACE_IFNAME])
     return UBUS_STATUS_INVALID_ARGUMENT;
 
+  if (tb[INTERFACE_RXCOST]) {
+    int cost = blobmsg_get_u32(tb[INTERFACE_RXCOST]);
+    if_conf = calloc(1, sizeof(struct interface_conf));
+    if (if_conf == NULL)
+      return UBUS_STATUS_UNKNOWN_ERROR;
+    if_conf->cost = cost;
+    //merge_ifconf(if_conf, if_conf, default_interface_conf);
+    //add_ifconf(if_conf, &interface_confs);
+  }
+
   ifname = blobmsg_get_string(tb[INTERFACE_IFNAME]);
 
-  ifp = add_interface(ifname, NULL);
+  ifp = add_interface(ifname, if_conf);
   if (ifp == NULL)
     return UBUS_STATUS_UNKNOWN_ERROR;
 

babeld/src/ubus.h

@@ -2,7 +2,7 @@
     IPC integration of babeld with OpenWrt.
 
     The ubus interface offers following functions:
-    - add_interface '{"ifname":"eth0"}'
+    - add_interface '{"ifname":"eth0", "rxcost":1024}'
     - get_info
     - get_neighbours
     - get_xroutes