summaryrefslogtreecommitdiffstats
path: root/src/shared/netif-util.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--src/shared/netif-util.c206
1 files changed, 206 insertions, 0 deletions
diff --git a/src/shared/netif-util.c b/src/shared/netif-util.c
new file mode 100644
index 0000000..f56c564
--- /dev/null
+++ b/src/shared/netif-util.c
@@ -0,0 +1,206 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <linux/if.h>
+#include <linux/if_arp.h>
+
+#include "arphrd-util.h"
+#include "device-util.h"
+#include "log-link.h"
+#include "memory-util.h"
+#include "netif-util.h"
+#include "siphash24.h"
+#include "sparse-endian.h"
+#include "strv.h"
+
+bool netif_has_carrier(uint8_t operstate, unsigned flags) {
+ /* see Documentation/networking/operstates.txt in the kernel sources */
+
+ if (operstate == IF_OPER_UP)
+ return true;
+
+ if (operstate != IF_OPER_UNKNOWN)
+ return false;
+
+ /* operstate may not be implemented, so fall back to flags */
+ return FLAGS_SET(flags, IFF_LOWER_UP | IFF_RUNNING) &&
+ !FLAGS_SET(flags, IFF_DORMANT);
+}
+
+int net_get_type_string(sd_device *device, uint16_t iftype, char **ret) {
+ const char *t;
+ char *p;
+
+ if (device &&
+ sd_device_get_devtype(device, &t) >= 0 &&
+ !isempty(t)) {
+ p = strdup(t);
+ if (!p)
+ return -ENOMEM;
+
+ *ret = p;
+ return 0;
+ }
+
+ t = arphrd_to_name(iftype);
+ if (!t)
+ return -ENOENT;
+
+ p = strdup(t);
+ if (!p)
+ return -ENOMEM;
+
+ *ret = ascii_strlower(p);
+ return 0;
+}
+
+const char *net_get_persistent_name(sd_device *device) {
+ assert(device);
+
+ /* fetch some persistent data unique (on this machine) to this device */
+ FOREACH_STRING(field, "ID_NET_NAME_ONBOARD", "ID_NET_NAME_SLOT", "ID_NET_NAME_PATH", "ID_NET_NAME_MAC") {
+ const char *name;
+
+ if (sd_device_get_property_value(device, field, &name) >= 0)
+ return name;
+ }
+
+ return NULL;
+}
+
+/* Used when generating hardware address by udev, and IPv4LL seed by networkd. */
+#define HASH_KEY SD_ID128_MAKE(d3,1e,48,fa,90,fe,4b,4c,9d,af,d5,d7,a1,b1,2e,8a)
+
+int net_get_unique_predictable_data(sd_device *device, bool use_sysname, uint64_t *ret) {
+ const char *name;
+
+ assert(device);
+ assert(ret);
+
+ /* net_get_persistent_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 actual device name. */
+ name = net_get_persistent_name(device);
+ if (!name && use_sysname)
+ (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);
+
+ return net_get_unique_predictable_data_from_name(name, &HASH_KEY, ret);
+}
+
+int net_get_unique_predictable_data_from_name(
+ const char *name,
+ const sd_id128_t *key,
+ uint64_t *ret) {
+
+ size_t l, sz;
+ uint8_t *v;
+ int r;
+
+ assert(name);
+ assert(key);
+ assert(ret);
+
+ l = strlen(name);
+ sz = sizeof(sd_id128_t) + l;
+ v = newa(uint8_t, sz);
+
+ /* 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. */
+ *ret = htole64(siphash24(v, sz, key->bytes));
+ return 0;
+}
+
+typedef struct Link {
+ const char *ifname;
+} Link;
+
+int net_verify_hardware_address(
+ const char *ifname,
+ bool is_static,
+ uint16_t iftype,
+ const struct hw_addr_data *ib_hw_addr, /* current or parent HW address */
+ struct hw_addr_data *new_hw_addr) {
+
+ Link link = { .ifname = ifname };
+
+ assert(new_hw_addr);
+
+ if (new_hw_addr->length == 0)
+ return 0;
+
+ if (new_hw_addr->length != arphrd_to_hw_addr_len(iftype)) {
+ if (is_static)
+ log_link_warning(&link,
+ "Specified MAC address with invalid length (%zu, expected %zu), refusing.",
+ new_hw_addr->length, arphrd_to_hw_addr_len(iftype));
+ return -EINVAL;
+ }
+
+ switch (iftype) {
+ case ARPHRD_ETHER:
+ /* see eth_random_addr() in the kernel */
+
+ if (ether_addr_is_null(&new_hw_addr->ether)) {
+ if (is_static)
+ log_link_warning(&link, "Specified MAC address is null, refusing.");
+ return -EINVAL;
+ }
+
+ if (ether_addr_is_broadcast(&new_hw_addr->ether)) {
+ if (is_static)
+ log_link_warning(&link, "Specified MAC address is broadcast, refusing.");
+ return -EINVAL;
+ }
+
+ if (ether_addr_is_multicast(&new_hw_addr->ether)) {
+ if (is_static)
+ log_link_warning(&link, "Specified MAC address has the multicast bit set, clearing the bit.");
+
+ new_hw_addr->bytes[0] &= 0xfe;
+ }
+
+ if (!is_static && !ether_addr_is_local(&new_hw_addr->ether))
+ /* Adjust local assignment bit when the MAC address is generated randomly. */
+ new_hw_addr->bytes[0] |= 0x02;
+
+ break;
+
+ case ARPHRD_INFINIBAND:
+ /* see ipoib_check_lladdr() in the kernel */
+
+ assert(ib_hw_addr);
+ assert(ib_hw_addr->length == INFINIBAND_ALEN);
+
+ if (is_static &&
+ (!memeqzero(new_hw_addr->bytes, INFINIBAND_ALEN - 8) ||
+ memcmp(new_hw_addr->bytes, ib_hw_addr->bytes, INFINIBAND_ALEN - 8) != 0))
+ log_link_warning(&link, "Only the last 8 bytes of the InifniBand MAC address can be changed, ignoring the first 12 bytes.");
+
+ if (memeqzero(new_hw_addr->bytes + INFINIBAND_ALEN - 8, 8)) {
+ if (is_static)
+ log_link_warning(&link, "The last 8 bytes of the InfiniBand MAC address cannot be null, refusing.");
+ return -EINVAL;
+ }
+
+ memcpy(new_hw_addr->bytes, ib_hw_addr->bytes, INFINIBAND_ALEN - 8);
+ break;
+
+ default:
+ if (is_static)
+ log_link_warning(&link, "Unsupported interface type %s%u to set MAC address, refusing.",
+ strna(arphrd_to_name(iftype)), iftype);
+ return -EINVAL;
+ }
+
+ return 0;
+}