colin/NetworkManager
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

core: support prefix-delegation.subnet-id

Browse Source
This commit is contained in:
Beniamino Galvani
2025-03-10 16:39:58 +01:00
parent b372caf0c4
commit b6386b3d27
2 changed files with 120 additions and 41 deletions
Download Patch File Download Diff File Expand all files Collapse all files

7
src/core/devices/nm-device.c
View File

@@ -11355,6 +11355,13 @@ _dev_ipdhcpx_notify(NMDhcpClient *client, const NMDhcpClientNotifyData *notify_d
switch (notify_data->notify_type) {
case NM_DHCP_CLIENT_NOTIFY_TYPE_PREFIX_DELEGATED:
nm_assert(!IS_IPv4);
if (notify_data->prefix_delegated.prefix->plen == 0
|| notify_data->prefix_delegated.prefix->plen > 64) {
_LOGW_ipdhcp(addr_family,
"ignoring invalid prefix-delegation with length %u",
notify_data->prefix_delegated.prefix->plen);
return;
}
/* Just re-emit. The device just contributes the prefix to the
* pool in NMPolicy, which decides about subnet allocation
* on the shared devices. */

128
src/core/nm-policy.c
View File

@@ -156,16 +156,14 @@ static gboolean hostname_retry_cb(gpointer user_data);
typedef struct {
NMPlatformIP6Address prefix;
NMDevice *device; /* The requesting ("uplink") device */
guint64 next_subnet; /* Cache of the next subnet number to be
* assigned from this prefix */
GHashTable *subnets; /* ifindex -> NMPlatformIP6Address */
GHashTable *map_subnet_id_to_ifindex; /* (guint64 *) subnet_id -> int ifindex */
GHashTable *map_ifindex_to_subnet; /* int ifindex -> (NMPlatformIP6Address *) prefix */
} IP6PrefixDelegation;
static void
_clear_ip6_subnet(gpointer key, gpointer value, gpointer user_data)
clear_ip6_subnet(int ifindex, NMPlatformIP6Address *subnet)
{
NMPlatformIP6Address *subnet = value;
NMDevice *device = nm_manager_get_device_by_ifindex(NM_MANAGER_GET, GPOINTER_TO_INT(key));
NMDevice *device = nm_manager_get_device_by_ifindex(NM_MANAGER_GET, ifindex);
if (device) {
/* We can not remove a subnet we already started announcing.
@@ -176,6 +174,12 @@ _clear_ip6_subnet(gpointer key, gpointer value, gpointer user_data)
g_slice_free(NMPlatformIP6Address, subnet);
}
static void
clear_ip6_subnet_entry(gpointer key, gpointer value, gpointer user_data)
{
clear_ip6_subnet(GPOINTER_TO_INT(key), value);
}
static void
clear_ip6_prefix_delegation(gpointer data)
{
@@ -187,8 +191,9 @@ clear_ip6_prefix_delegation(gpointer data)
nm_inet6_ntop(&delegation->prefix.address, sbuf),
delegation->prefix.plen);
g_hash_table_foreach(delegation->subnets, _clear_ip6_subnet, NULL);
g_hash_table_destroy(delegation->subnets);
g_hash_table_foreach(delegation->map_ifindex_to_subnet, clear_ip6_subnet_entry, NULL);
g_hash_table_destroy(delegation->map_ifindex_to_subnet);
g_hash_table_destroy(delegation->map_subnet_id_to_ifindex);
}
static void
@@ -218,43 +223,109 @@ ip6_subnet_from_delegation(IP6PrefixDelegation *delegation, NMDevice *device)
NMPlatformIP6Address *subnet;
int ifindex = nm_device_get_ifindex(device);
char sbuf[NM_INET_ADDRSTRLEN];
NMSettingPrefixDelegation *s_pd;
gint64 wanted_subnet_id = -1;
guint64 num_subnets;
guint64 old_subnet_id;
subnet = g_hash_table_lookup(delegation->subnets, GINT_TO_POINTER(ifindex));
if (!subnet) {
/* Check for out-of-prefixes condition. */
if (delegation->next_subnet >= (1 << (64 - delegation->prefix.plen))) {
nm_assert(delegation->prefix.plen > 0 && delegation->prefix.plen <= 64);
s_pd = nm_device_get_applied_setting(device, NM_TYPE_SETTING_PREFIX_DELEGATION);
if (s_pd) {
wanted_subnet_id = nm_setting_prefix_delegation_get_subnet_id(s_pd);
}
/* Try to use the cached subnet assigned to the interface */
subnet = g_hash_table_lookup(delegation->map_ifindex_to_subnet, GINT_TO_POINTER(ifindex));
if (subnet) {
old_subnet_id = nm_ip6_addr_get_subnet_id(&subnet->address, delegation->prefix.plen);
if (wanted_subnet_id != -1 && wanted_subnet_id != old_subnet_id) {
/* The device had a subnet assigned before, but now wants a
* different subnet-id. Release the old subnet and continue below
* to get a new one. */
clear_ip6_subnet(ifindex, subnet);
subnet = NULL;
g_hash_table_remove(delegation->map_ifindex_to_subnet, GINT_TO_POINTER(ifindex));
g_hash_table_remove(delegation->map_subnet_id_to_ifindex, &old_subnet_id);
} else {
goto subnet_found;
}
}
/* Check for out-of-prefixes condition */
num_subnets = 1 << (64 - delegation->prefix.plen);
if (nm_g_hash_table_size(delegation->map_subnet_id_to_ifindex) >= num_subnets) {
_LOGD(LOGD_IP6,
"ipv6-pd: no more prefixes in %s/%d",
"ipv6-pd: no more prefixes in %s/%u",
nm_inet6_ntop(&delegation->prefix.address, sbuf),
delegation->prefix.plen);
return FALSE;
}
/* Allocate a new subnet. */
/* Try to honor the "prefix-delegation.subnet-id" property */
if (wanted_subnet_id >= 0) {
gpointer value;
NMDevice *other_device;
if (g_hash_table_lookup_extended(delegation->map_subnet_id_to_ifindex,
&wanted_subnet_id,
NULL,
&value)) {
other_device = nm_manager_get_device_by_ifindex(NM_MANAGER_GET, GPOINTER_TO_INT(value));
_LOGW(LOGD_IP6,
"ipv6-pd: subnet-id 0x%" G_GINT64_MODIFIER
"x wanted by device %s is already in use by "
"device %s (ifindex %d)",
(guint64) wanted_subnet_id,
nm_device_get_iface(device),
other_device ? nm_device_get_ip_iface(other_device) : NULL,
GPOINTER_TO_INT(value));
wanted_subnet_id = -1;
}
}
/* If we don't have a subnet-id yet, find the first one available */
if (wanted_subnet_id < 0) {
guint64 i;
for (i = 0; i < num_subnets; i++) {
if (!g_hash_table_lookup_extended(delegation->map_subnet_id_to_ifindex,
&i,
NULL,
NULL)) {
wanted_subnet_id = (gint64) i;
break;
}
}
if (wanted_subnet_id < 0) {
/* We already verified that there are available subnets, this should not happen */
return nm_assert_unreachable_val(FALSE);
}
}
/* Allocate a new subnet */
subnet = g_slice_new0(NMPlatformIP6Address);
g_hash_table_insert(delegation->subnets, GINT_TO_POINTER(ifindex), subnet);
g_hash_table_insert(delegation->map_ifindex_to_subnet, GINT_TO_POINTER(ifindex), subnet);
g_hash_table_insert(delegation->map_subnet_id_to_ifindex,
nm_memdup(&wanted_subnet_id, sizeof(guint64)),
GINT_TO_POINTER(ifindex));
subnet->plen = 64;
subnet->address.s6_addr32[0] =
delegation->prefix.address.s6_addr32[0] | htonl(delegation->next_subnet >> 32);
delegation->prefix.address.s6_addr32[0] | htonl(wanted_subnet_id >> 32);
subnet->address.s6_addr32[1] =
delegation->prefix.address.s6_addr32[1] | htonl(delegation->next_subnet);
/* Out subnet pool management is pretty unsophisticated. We only add
* the subnets and index them by ifindex. That keeps the implementation
* simple and the dead entries make it easy to reuse the same subnet on
* subsequent activations. On the other hand they may waste the subnet
* space. */
delegation->next_subnet++;
}
delegation->prefix.address.s6_addr32[1] | htonl(wanted_subnet_id);
subnet_found:
subnet->timestamp = delegation->prefix.timestamp;
subnet->lifetime = delegation->prefix.lifetime;
subnet->preferred = delegation->prefix.preferred;
_LOGD(LOGD_IP6,
"ipv6-pd: %s allocated from a /%d prefix on %s",
"ipv6-pd: %s/64 (subnet-id 0x%" G_GINT64_MODIFIER "x) allocated from a /%d prefix on %s",
nm_inet6_ntop(&subnet->address, sbuf),
(guint64) wanted_subnet_id,
delegation->prefix.plen,
nm_device_get_iface(device));
@@ -345,8 +416,9 @@ device_ip6_prefix_delegated(NMDevice *device,
if (i == priv->ip6_prefix_delegations->len) {
/* Allocate a delegation for new prefix. */
delegation = nm_g_array_append_new(priv->ip6_prefix_delegations, IP6PrefixDelegation);
delegation->subnets = g_hash_table_new(nm_direct_hash, NULL);
delegation->next_subnet = 0;
delegation->map_subnet_id_to_ifindex =
g_hash_table_new_full(nm_puint64_hash, nm_puint64_equal, g_free, NULL);
delegation->map_ifindex_to_subnet = g_hash_table_new(nm_direct_hash, NULL);
}
delegation->device = device;