summaryrefslogtreecommitdiffstats
path: root/src/shared/netif-naming-scheme.h
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 15:35:18 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 15:35:18 +0000
commitb750101eb236130cf056c675997decbac904cc49 (patch)
treea5df1a06754bdd014cb975c051c83b01c9a97532 /src/shared/netif-naming-scheme.h
parentInitial commit. (diff)
downloadsystemd-b750101eb236130cf056c675997decbac904cc49.tar.xz
systemd-b750101eb236130cf056c675997decbac904cc49.zip
Adding upstream version 252.22.upstream/252.22
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/shared/netif-naming-scheme.h')
-rw-r--r--src/shared/netif-naming-scheme.h88
1 files changed, 88 insertions, 0 deletions
diff --git a/src/shared/netif-naming-scheme.h b/src/shared/netif-naming-scheme.h
new file mode 100644
index 0000000..4fa9170
--- /dev/null
+++ b/src/shared/netif-naming-scheme.h
@@ -0,0 +1,88 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+#pragma once
+
+#include <stdbool.h>
+
+#include "macro.h"
+
+/* So here's the deal: net_id is supposed to be an exercise in providing stable names for network devices. However, we
+ * also want to keep updating the naming scheme used in future versions of net_id. These two goals of course are
+ * contradictory: on one hand we want things to not change and on the other hand we want them to improve. Our way out
+ * of this dilemma is to introduce the "naming scheme" concept: each time we improve the naming logic we define a new
+ * flag for it. Then, we keep a list of schemes, each identified by a name associated with the flags it implements. Via
+ * a kernel command line and environment variable we then allow the user to pick the scheme they want us to follow:
+ * installers could "freeze" the used scheme at the moment of installation this way.
+ *
+ * Developers: each time you tweak the naming logic here, define a new flag below, and condition the tweak with
+ * it. Each time we do a release we'll then add a new scheme entry and include all newly defined flags.
+ *
+ * Note that this is only half a solution to the problem though: not only udev/net_id gets updated all the time, the
+ * kernel gets too. And thus a kernel that previously didn't expose some sysfs attribute we look for might eventually
+ * do, and thus affect our naming scheme too. Thus, enforcing a naming scheme will make interfacing more stable across
+ * OS versions, but not fully stabilize them. */
+typedef enum NamingSchemeFlags {
+ /* First, the individual features */
+ NAMING_SR_IOV_V = 1 << 0, /* Use "v" suffix for SR-IOV, see 609948c7043a */
+ NAMING_NPAR_ARI = 1 << 1, /* Use NPAR "ARI", see 6bc04997b6ea */
+ NAMING_INFINIBAND = 1 << 2, /* Use "ib" prefix for infiniband, see 938d30aa98df */
+ NAMING_ZERO_ACPI_INDEX = 1 << 3, /* Use zero acpi_index field, see d81186ef4f6a */
+ NAMING_ALLOW_RERENAMES = 1 << 4, /* Allow re-renaming of devices, see #9006 */
+ NAMING_STABLE_VIRTUAL_MACS = 1 << 5, /* Use device name to generate MAC, see 6d3646406560 */
+ NAMING_NETDEVSIM = 1 << 6, /* Generate names for netdevsim devices, see eaa9d507d855 */
+ NAMING_LABEL_NOPREFIX = 1 << 7, /* Don't prepend ID_NET_LABEL_ONBOARD with interface type prefix */
+ NAMING_NSPAWN_LONG_HASH = 1 << 8, /* Shorten nspawn interfaces by including 24bit hash, instead of simple truncation */
+ NAMING_BRIDGE_NO_SLOT = 1 << 9, /* Don't use PCI hotplug slot information if the corresponding device is a PCI bridge */
+ NAMING_SLOT_FUNCTION_ID = 1 << 10, /* Use function_id if present to identify PCI hotplug slots */
+ NAMING_16BIT_INDEX = 1 << 11, /* Allow full 16-bit for the onboard index */
+ NAMING_REPLACE_STRICTLY = 1 << 12, /* Use udev_replace_ifname() for NAME= rule */
+ NAMING_XEN_VIF = 1 << 13, /* Generate names for Xen netfront devices */
+ NAMING_BRIDGE_MULTIFUNCTION_SLOT = 1 << 14, /* Use PCI hotplug slot information associated with bridge, but only if PCI device is multifunction */
+ NAMING_DEVICETREE_ALIASES = 1 << 15, /* Generate names from devicetree aliases */
+
+ /* And now the masks that combine the features above */
+ NAMING_V238 = 0,
+ NAMING_V239 = NAMING_V238 | NAMING_SR_IOV_V | NAMING_NPAR_ARI,
+ NAMING_V240 = NAMING_V239 | NAMING_INFINIBAND | NAMING_ZERO_ACPI_INDEX | NAMING_ALLOW_RERENAMES,
+ NAMING_V241 = NAMING_V240 | NAMING_STABLE_VIRTUAL_MACS,
+ NAMING_V243 = NAMING_V241 | NAMING_NETDEVSIM | NAMING_LABEL_NOPREFIX,
+ NAMING_V245 = NAMING_V243 | NAMING_NSPAWN_LONG_HASH,
+ NAMING_V247 = NAMING_V245 | NAMING_BRIDGE_NO_SLOT,
+ NAMING_V249 = NAMING_V247 | NAMING_SLOT_FUNCTION_ID | NAMING_16BIT_INDEX | NAMING_REPLACE_STRICTLY,
+ NAMING_V250 = NAMING_V249 | NAMING_XEN_VIF,
+ NAMING_V251 = NAMING_V250 | NAMING_BRIDGE_MULTIFUNCTION_SLOT,
+ NAMING_V252 = NAMING_V251 | NAMING_DEVICETREE_ALIASES,
+
+ EXTRA_NET_NAMING_SCHEMES
+
+ _NAMING_SCHEME_FLAGS_INVALID = -EINVAL,
+} NamingSchemeFlags;
+
+typedef struct NamingScheme {
+ const char *name;
+ NamingSchemeFlags flags;
+} NamingScheme;
+
+const NamingScheme* naming_scheme_from_name(const char *name);
+const NamingScheme* naming_scheme(void);
+
+static inline bool naming_scheme_has(NamingSchemeFlags flags) {
+ return FLAGS_SET(naming_scheme()->flags, flags);
+}
+
+typedef enum NamePolicy {
+ NAMEPOLICY_KERNEL,
+ NAMEPOLICY_KEEP,
+ NAMEPOLICY_DATABASE,
+ NAMEPOLICY_ONBOARD,
+ NAMEPOLICY_SLOT,
+ NAMEPOLICY_PATH,
+ NAMEPOLICY_MAC,
+ _NAMEPOLICY_MAX,
+ _NAMEPOLICY_INVALID = -EINVAL,
+} NamePolicy;
+
+const char *name_policy_to_string(NamePolicy p) _const_;
+NamePolicy name_policy_from_string(const char *p) _pure_;
+
+const char *alternative_names_policy_to_string(NamePolicy p) _const_;
+NamePolicy alternative_names_policy_from_string(const char *p) _pure_;