udev,networkd: use the interface name as fallback basis for MAC and IPv4LL seed

[thirdparty/systemd.git] / src / libsystemd-network / network-internal.c

diff --git a/src/libsystemd-network/network-internal.c b/src/libsystemd-network/network-internal.c
index b3b134d65057c467d108c222da695313198b4c63..9e7838527c59fcb85ca0622e2fb06ac6121648f0 100644 (file)
--- a/src/libsystemd-network/network-internal.c
+++ b/src/libsystemd-network/network-internal.c
@@ -10,6 +10,7 @@
 #include "alloc-util.h"
 #include "condition.h"
 #include "conf-parser.h"
+#include "device-util.h"
 #include "dhcp-lease-internal.h"
 #include "ether-addr-util.h"
 #include "hexdecoct.h"
@@ -40,31 +41,35 @@ const char *net_get_name(sd_device *device) {
 
 int net_get_unique_predictable_data(sd_device *device, uint64_t *result) {
         size_t l, sz = 0;
-        const char *name = NULL;
+        const char *name;
         int r;
         uint8_t *v;
 
         assert(device);
 
+        /* net_get_name() will return one of the device names based on stable information about the
+         * device. If this is not available, we fall back to using the device name. */
         name = net_get_name(device);
         if (!name)
-                return -ENOENT;
+                (void) sd_device_get_sysname(device, &name);
+        if (!name)
+                return log_device_debug_errno(device, SYNTHETIC_ERRNO(ENODATA),
+                                              "No stable identifying information found");
 
+        log_device_debug(device, "Using \"%s\" as stable identifying information", name);
         l = strlen(name);
         sz = sizeof(sd_id128_t) + l;
         v = alloca(sz);
 
-        /* fetch some persistent data unique to this machine */
+        /* Fetch some persistent data unique to this machine */
         r = sd_id128_get_machine((sd_id128_t*) v);
         if (r < 0)
                  return r;
         memcpy(v + sizeof(sd_id128_t), name, l);
 
-        /* Let's hash the machine ID plus the device name. We
-        * use a fixed, but originally randomly created hash
-        * key here. */
+        /* Let's hash the machine ID plus the device name. We use
+         * a fixed, but originally randomly created hash key here. */
         *result = htole64(siphash24(v, sz, HASH_KEY.bytes));
-
         return 0;
 }