document ability to disable MACAddressPolicy

While it is currently possible to either not set MACAddressPolicy or set
it to a value different from "persistent" or "random", it is not obvious
that a user can do so. Add a policy, "none", which simply retains kernel
MAC addresses (same as not filling in the policy at all) and document it
so that users are aware of this setting.

Signed-off-by: Jacob Keller <jacob.keller@gmail.com>

2 files changed, 4 insertions, 1 deletions

diff --git a/src/udev/net/link-config.c b/src/udev/net/link-config.c
index 63e54db56e..4b8c5053a4 100644
--- a/src/udev/net/link-config.c
+++ b/src/udev/net/link-config.c
@@ -460,6 +460,7 @@ int link_config_apply(link_config_ctx *ctx, link_config *config,
                                 mac = &generated_mac;
                         }
                         break;
+                case MACPOLICY_NONE:
                 default:
                         mac = config->mac;
         }
@@ -492,7 +493,8 @@ int link_get_driver(link_config_ctx *ctx, struct udev_device *device, char **ret
 
 static const char* const mac_policy_table[_MACPOLICY_MAX] = {
         [MACPOLICY_PERSISTENT] = "persistent",
-        [MACPOLICY_RANDOM] = "random"
+        [MACPOLICY_RANDOM] = "random",
+        [MACPOLICY_NONE] = "none"
 };
 
 DEFINE_STRING_TABLE_LOOKUP(mac_policy, MACPolicy);
diff --git a/src/udev/net/link-config.h b/src/udev/net/link-config.h
index 9875057e84..c52db2ce55 100644
--- a/src/udev/net/link-config.h
+++ b/src/udev/net/link-config.h
@@ -32,6 +32,7 @@ typedef struct link_config link_config;
 typedef enum MACPolicy {
         MACPOLICY_PERSISTENT,
         MACPOLICY_RANDOM,
+        MACPOLICY_NONE,
         _MACPOLICY_MAX,
         _MACPOLICY_INVALID = -1
 } MACPolicy;