platform: configure HSR interlink from property

Uses the `hsr.interlink` property defined in the previous
commit to configure the property in the kernel.

src/core/devices/nm-device-hsr.c

@@ -116,18 +116,31 @@ create_and_realize(NMDevice              *device,
                    const NMPlatformLink **out_plink,
                    GError               **error)
 {
-    const char      *iface = nm_device_get_iface(device);
-    NMSettingHsr    *s_hsr;
-    NMPlatformLnkHsr lnk = {};
-    int              r;
+    const char        *iface   = nm_device_get_iface(device);
+    nm_auto_free char *err_msg = NULL;
+    NMSettingHsr      *s_hsr;
+    NMPlatformLnkHsr   lnk = {};
+    int                r   = 0;
 
     s_hsr = _nm_connection_get_setting(connection, NM_TYPE_SETTING_HSR);
+
     nm_assert(s_hsr);
 
     if (nm_setting_hsr_get_port1(s_hsr) != NULL)
         lnk.port1 = nm_platform_link_get_ifindex(NM_PLATFORM_GET, nm_setting_hsr_get_port1(s_hsr));
     if (nm_setting_hsr_get_port2(s_hsr) != NULL)
         lnk.port2 = nm_platform_link_get_ifindex(NM_PLATFORM_GET, nm_setting_hsr_get_port2(s_hsr));
+    if (nm_setting_hsr_get_interlink(s_hsr) != NULL) {
+        const char *ifname  = nm_setting_hsr_get_interlink(s_hsr);
+        int         ifindex = nm_platform_link_get_ifindex(NM_PLATFORM_GET, ifname);
+
+        if (ifindex <= 0) {
+            err_msg = g_strdup_printf("interlink port '%s' does not exist", ifname);
+            goto out;
+        }
+
+        lnk.interlink = ifindex;
+    }
 
     lnk.multicast_spec   = nm_setting_hsr_get_multicast_spec(s_hsr);
     lnk.prp              = nm_setting_hsr_get_prp(s_hsr);
@@ -136,13 +149,18 @@ create_and_realize(NMDevice              *device,
     r = nm_platform_link_hsr_add(nm_device_get_platform(device), iface, &lnk, out_plink);
 
     if (r < 0) {
+        err_msg = g_strdup(nm_strerror(r) ?: "unknown");
+    }
+
+out:
+    if (err_msg) {
         g_set_error(error,
                     NM_DEVICE_ERROR,
                     NM_DEVICE_ERROR_CREATION_FAILED,
                     "Failed to create HSR interface '%s' for '%s': %s",
                     iface,
                     nm_connection_get_id(connection),
-                    nm_strerror(r));
+                    err_msg);
         return FALSE;
     }
 

src/libnm-platform/nm-linux-platform.c

@@ -253,7 +253,8 @@ G_STATIC_ASSERT(RTA_MAX == (__RTA_MAX - 1));
 #define IFLA_HSR_SEQ_NR           5
 #define IFLA_HSR_VERSION          6
 #define IFLA_HSR_PROTOCOL         7
-#define __IFLA_HSR_MAX            8
+#define IFLA_HSR_INTERLINK        8
+#define __IFLA_HSR_MAX            9
 
 /*****************************************************************************/
 
@@ -5225,6 +5226,10 @@ _nl_msg_new_link_set_linkinfo(struct nl_msg *msg, NMLinkType link_type, gconstpo
             NLA_PUT_U8(msg, IFLA_HSR_VERSION, props->protocol_version);
         }
 
+        if (props->interlink > 0) {
+            NLA_PUT_U32(msg, IFLA_HSR_INTERLINK, props->interlink);
+        }
+
         break;
     }
     case NM_LINK_TYPE_SIT:

src/libnm-platform/nm-platform.c

@@ -6560,6 +6560,8 @@ nm_platform_lnk_gre_to_string(const NMPlatformLnkGre *lnk, char *buf, gsize len)
 const char *
 nm_platform_lnk_hsr_to_string(const NMPlatformLnkHsr *lnk, char *buf, gsize len)
 {
+    char interlink_buf[30];
+
     if (!nm_utils_to_string_buffer_init_null(lnk, &buf, &len))
         return buf;
 
@@ -6570,13 +6572,16 @@ nm_platform_lnk_hsr_to_string(const NMPlatformLnkHsr *lnk, char *buf, gsize len)
                "port2 %d "
                "supervision_address " NM_ETHER_ADDR_FORMAT_STR " multicast_spec %u "
                "prp %s "
-               "protocol_version %d",
+               "protocol_version %d"
+               "%s", /* interlink */
                lnk->port1,
                lnk->port2,
                NM_ETHER_ADDR_FORMAT_VAL(&lnk->supervision_address),
                lnk->multicast_spec,
                lnk->prp ? "on" : "off",
-               lnk->protocol_version);
+               lnk->protocol_version,
+               lnk->interlink ? nm_sprintf_buf(interlink_buf, " interlink %d", lnk->interlink)
+                              : "");
     return buf;
 }
 
@@ -8494,7 +8499,8 @@ nm_platform_lnk_hsr_hash_update(const NMPlatformLnkHsr *obj, NMHashState *h)
                         obj->supervision_address,
                         obj->multicast_spec,
                         NM_HASH_COMBINE_BOOLS(guint8, obj->prp),
-                        obj->protocol_version);
+                        obj->protocol_version,
+                        obj->interlink);
 }
 
 int
@@ -8507,6 +8513,7 @@ nm_platform_lnk_hsr_cmp(const NMPlatformLnkHsr *a, const NMPlatformLnkHsr *b)
     NM_CMP_FIELD(a, b, multicast_spec);
     NM_CMP_FIELD_BOOL(a, b, prp);
     NM_CMP_FIELD(a, b, protocol_version);
+    NM_CMP_FIELD(a, b, interlink);
     return 0;
 }
 

src/libnm-platform/nm-platform.h

@@ -851,6 +851,7 @@ typedef struct {
 typedef struct {
     int         port1;
     int         port2;
+    int         interlink;
     NMEtherAddr supervision_address;
     gint8       protocol_version;
     guint8      multicast_spec;