resolved: move verification that link is unmanaged into the proper bus calls

Previously, we checked only for the various SetLinkXYZ() calls on the Manager
object exposed on the bus if the specified interface is managed/unmanaged by
networkd (as we don't permit overriding DNS configuration via bus calls if
networkd owns the device), but the equivalent SetXYZ() calls on the Link object
did not have such a check. Fix that by moving the appropriate check into the
latter, as the former just calls that anyway.

1 files changed, 41 insertions, 0 deletions

diff --git a/src/resolve/resolved-link-bus.c b/src/resolve/resolved-link-bus.c
index 6aff427192..bfb87d78e7 100644
--- a/src/resolve/resolved-link-bus.c
+++ b/src/resolve/resolved-link-bus.c
@@ -18,6 +18,7 @@
 ***/
 
 #include "alloc-util.h"
+#include "bus-common-errors.h"
 #include "bus-util.h"
 #include "parse-util.h"
 #include "resolve-util.h"
@@ -158,6 +159,17 @@ static int property_get_dnssec_supported(
         return sd_bus_message_append(reply, "b", link_dnssec_supported(l));
 }
 
+static int verify_unmanaged_link(Link *l, sd_bus_error *error) {
+        assert(l);
+
+        if (l->flags & IFF_LOOPBACK)
+                return sd_bus_error_setf(error, BUS_ERROR_LINK_BUSY, "Link %s is loopback device.", l->name);
+        if (l->is_managed)
+                return sd_bus_error_setf(error, BUS_ERROR_LINK_BUSY, "Link %s is managed.", l->name);
+
+        return 0;
+}
+
 int bus_link_method_set_dns_servers(sd_bus_message *message, void *userdata, sd_bus_error *error) {
         _cleanup_free_ struct in_addr_data *dns = NULL;
         size_t allocated = 0, n = 0;
@@ -168,6 +180,10 @@ int bus_link_method_set_dns_servers(sd_bus_message *message, void *userdata, sd_
         assert(message);
         assert(l);
 
+        r = verify_unmanaged_link(l, error);
+        if (r < 0)
+                return r;
+
         r = sd_bus_message_enter_container(message, 'a', "(iay)");
         if (r < 0)
                 return r;
@@ -249,6 +265,10 @@ int bus_link_method_set_domains(sd_bus_message *message, void *userdata, sd_bus_
         assert(message);
         assert(l);
 
+        r = verify_unmanaged_link(l, error);
+        if (r < 0)
+                return r;
+
         r = sd_bus_message_enter_container(message, 'a', "(sb)");
         if (r < 0)
                 return r;
@@ -328,6 +348,10 @@ int bus_link_method_set_llmnr(sd_bus_message *message, void *userdata, sd_bus_er
         assert(message);
         assert(l);
 
+        r = verify_unmanaged_link(l, error);
+        if (r < 0)
+                return r;
+
         r = sd_bus_message_read(message, "s", &llmnr);
         if (r < 0)
                 return r;
@@ -356,6 +380,10 @@ int bus_link_method_set_mdns(sd_bus_message *message, void *userdata, sd_bus_err
         assert(message);
         assert(l);
 
+        r = verify_unmanaged_link(l, error);
+        if (r < 0)
+                return r;
+
         r = sd_bus_message_read(message, "s", &mdns);
         if (r < 0)
                 return r;
@@ -384,6 +412,10 @@ int bus_link_method_set_dnssec(sd_bus_message *message, void *userdata, sd_bus_e
         assert(message);
         assert(l);
 
+        r = verify_unmanaged_link(l, error);
+        if (r < 0)
+                return r;
+
         r = sd_bus_message_read(message, "s", &dnssec);
         if (r < 0)
                 return r;
@@ -411,6 +443,10 @@ int bus_link_method_set_dnssec_negative_trust_anchors(sd_bus_message *message, v
         assert(message);
         assert(l);
 
+        r = verify_unmanaged_link(l, error);
+        if (r < 0)
+                return r;
+
         r = sd_bus_message_read_strv(message, &ntas);
         if (r < 0)
                 return r;
@@ -442,10 +478,15 @@ int bus_link_method_set_dnssec_negative_trust_anchors(sd_bus_message *message, v
 
 int bus_link_method_revert(sd_bus_message *message, void *userdata, sd_bus_error *error) {
         Link *l = userdata;
+        int r;
 
         assert(message);
         assert(l);
 
+        r = verify_unmanaged_link(l, error);
+        if (r < 0)
+                return r;
+
         link_flush_settings(l);
         link_allocate_scopes(l);
         link_add_rrs(l, false);