networkd: merge ll addressing fallback modes into normal "boolean" values

They are not really boolean, because we have both ipv4 and ipv6, but
for each protocol we have either unset, no, and yes.

From https://github.com/systemd/systemd/issues/13316#issuecomment-582906817:
LinkLocalAddressing must be a boolean option, at least for ipv4:
- LinkLocalAddressing=no => no LL at all.

- LinkLocalAddressing=yes + Static Address => invalid configuration, warn and
  interpret as LinkLocalAddressing=no, no LL at all.

(we check that during parsing and reject)

- LinkLocalAddressing=yes + DHCP => LL process should be subordinated to the
  DHCP one, an LL address must be acquired at start or after a short N
  unsuccessful DHCP attemps, and must not stop DHCP to keeping trying. When a
  DHCP address is acquired, drop the LL address. If the DHCP address is lost,
  re-adquire a new LL address.

(next patch will move in this direction)

- LinkLocalAddressing=fallback has no reason to exist, because LL address must
  always be allocated as a fallback option when using DHCP. Having both DHCP
  and LL address at the same time is an RFC violation, so
  LinkLocalAdressing=yes correctly implemented is already the "fallback"
  behavior. The fallback option must be deprecated and if present in older
  configs must be interpreted as LinkLocalAddressing=yes.

(removed)

- And for IPv6, the LinkLocalAddress option has any sense at all? IPv6-LL
  address aren't required to be always set for every IPv6 enabled interface (in
  this case, coexisting with static or dynamic address if any)? Shouldn't be
  always =yes?

(good question)

This effectively reverts 29e81083bd2fcb2dbf83f67ef358c7d25adf7e9d. There is no
special "fallback" mode now, so the check doesn't make sense anymore.

diff --git a/man/systemd.network.xml b/man/systemd.network.xml
index 1f389a05f3dde31b7e20b98c456bfe9d39be310f..3b029dca63cc1ac62e023eae323d394e47a67242 100644 (file)
--- a/man/systemd.network.xml
+++ b/man/systemd.network.xml
@@ -364,17 +364,13 @@
         <varlistentry>
           <term><varname>LinkLocalAddressing=</varname></term>
           <listitem>
-            <para>Enables link-local address autoconfiguration. Accepts <literal>yes</literal>,
-            <literal>no</literal>, <literal>ipv4</literal>, <literal>ipv6</literal>,
-            <literal>fallback</literal>, or <literal>ipv4-fallback</literal>. If
-            <literal>fallback</literal> or <literal>ipv4-fallback</literal> is specified, then an IPv4
-            link-local address is configured only when DHCPv4 fails. If <literal>fallback</literal>,
-            an IPv6 link-local address is always configured, and if <literal>ipv4-fallback</literal>,
-            the address is not configured. Note that, the fallback mechanism works only when DHCPv4
-            client is enabled, that is, it requires <literal>DHCP=yes</literal> or
-            <literal>DHCP=ipv4</literal>. If <varname>Bridge=</varname> is set, defaults to
-            <literal>no</literal>, and if not, defaults to <literal>ipv6</literal>.
-            </para>
+            <para>Enables link-local address autoconfiguration. Accepts <option>yes</option>,
+            <option>no</option>, <option>ipv4</option>, and <option>ipv6</option>. An IPv6 link-local address
+            is configured when <option>yes</option> or <option>ipv6</option>. An IPv4 link-local address is
+            configured when <option>yes</option> or <option>ipv4</option>.</para>
+
+            <para>Defaults to <option>no</option> when <varname>Bridge=yes</varname> is set, and
+            <option>ipv6</option> otherwise.</para>
           </listitem>
         </varlistentry>
         <varlistentry>

diff --git a/src/basic/string-table.h b/src/basic/string-table.h
index b6b3611acedb5c1679f11c16e2c71301bcbaa3a9..4911a455c5864b20dc9e4503f619d64377659104 100644 (file)
--- a/src/basic/string-table.h
+++ b/src/basic/string-table.h
@@ -28,13 +28,12 @@ ssize_t string_table_lookup(const char * const *table, size_t len, const char *k
 
 #define _DEFINE_STRING_TABLE_LOOKUP_FROM_STRING_WITH_BOOLEAN(name,type,yes,scope) \
         scope type name##_from_string(const char *s) {                  \
-                int b;                                                  \
                 if (!s)                                                 \
                         return -1;                                      \
-                b = parse_boolean(s);                                   \
+                int b = parse_boolean(s);                               \
                 if (b == 0)                                             \
                         return (type) 0;                                \
-                else if (b > 0)                                         \
+                if (b > 0)                                              \
                         return yes;                                     \
                 return (type) string_table_lookup(name##_table, ELEMENTSOF(name##_table), s); \
         }

diff --git a/src/network/networkd-dhcp4.c b/src/network/networkd-dhcp4.c
index a521822a50ead4c5584f375c3e16f58a8b618859..8a2292b1a60909efdb4a376d58ddb0b094eb6060 100644 (file)
--- a/src/network/networkd-dhcp4.c
+++ b/src/network/networkd-dhcp4.c
@@ -1048,8 +1048,7 @@ static int dhcp4_handler(sd_dhcp_client *client, int event, void *userdata) {
 
         switch (event) {
                 case SD_DHCP_CLIENT_EVENT_STOP:
-
-                        if (link_ipv4ll_enabled(link, ADDRESS_FAMILY_FALLBACK_IPV4)) {
+                        if (link_ipv4ll_enabled(link)) {
                                 assert(link->ipv4ll);
 
                                 log_link_debug(link, "DHCP client is stopped. Acquiring IPv4 link-local address");

diff --git a/src/network/networkd-ipv4ll.c b/src/network/networkd-ipv4ll.c
index 598af25de66b0e1b5051c1b560242af629a6cab6..7e1c1ac16eae6c558c81a7f506573688563676d5 100644 (file)
--- a/src/network/networkd-ipv4ll.c
+++ b/src/network/networkd-ipv4ll.c
@@ -148,7 +148,7 @@ int ipv4ll_configure(Link *link) {
 
         assert(link);
 
-        if (!link_ipv4ll_enabled(link, ADDRESS_FAMILY_IPV4 | ADDRESS_FAMILY_FALLBACK_IPV4))
+        if (!link_ipv4ll_enabled(link))
                 return 0;
 
         if (!link->ipv4ll) {

diff --git a/src/network/networkd-link.c b/src/network/networkd-link.c
index 4feda54c7009f5335ae8f6233d3e5c3172709024..baaf0b8812433154d1260bf7cd2721e757e68631 100644 (file)
--- a/src/network/networkd-link.c
+++ b/src/network/networkd-link.c
@@ -55,9 +55,8 @@
 #include "util.h"
 #include "vrf.h"
 
-bool link_ipv4ll_enabled(Link *link, AddressFamily mask) {
+bool link_ipv4ll_enabled(Link *link) {
         assert(link);
-        assert((mask & ~(ADDRESS_FAMILY_IPV4 | ADDRESS_FAMILY_FALLBACK_IPV4)) == 0);
 
         if (link->flags & IFF_LOOPBACK)
                 return false;
@@ -80,7 +79,7 @@ bool link_ipv4ll_enabled(Link *link, AddressFamily mask) {
         if (link->network->bond)
                 return false;
 
-        return link->network->link_local & mask;
+        return link->network->link_local & ADDRESS_FAMILY_IPV4;
 }
 
 bool link_ipv6ll_enabled(Link *link) {
@@ -795,7 +794,7 @@ void link_check_ready(Link *link) {
                 bool has_ndisc_address = false;
                 NDiscAddress *n;
 
-                if (link_ipv4ll_enabled(link, ADDRESS_FAMILY_IPV4) && !link->ipv4ll_address_configured) {
+                if (link_ipv4ll_enabled(link) && !link->ipv4ll_address_configured) {
                         log_link_debug(link, "%s(): IPv4LL is not configured.", __func__);
                         return;
                 }
@@ -814,7 +813,7 @@ void link_check_ready(Link *link) {
 
                 if ((link_dhcp4_enabled(link) || link_dhcp6_enabled(link)) &&
                     !link->dhcp_address && set_isempty(link->dhcp6_addresses) && !has_ndisc_address &&
-                    !(link_ipv4ll_enabled(link, ADDRESS_FAMILY_FALLBACK_IPV4) && link->ipv4ll_address_configured)) {
+                    !(link_ipv4ll_enabled(link) && link->ipv4ll_address_configured)) {
                         log_link_debug(link, "%s(): DHCP4 or DHCP6 is enabled but no dynamic address is assigned yet.", __func__);
                         return;
                 }
@@ -824,7 +823,7 @@ void link_check_ready(Link *link) {
                             !(link->dhcp6_address_configured && link->dhcp6_route_configured) &&
                             !(link->dhcp6_pd_address_configured && link->dhcp6_pd_route_configured) &&
                             !(link->ndisc_addresses_configured && link->ndisc_routes_configured) &&
-                            !(link_ipv4ll_enabled(link, ADDRESS_FAMILY_FALLBACK_IPV4) && link->ipv4ll_address_configured)) {
+                            !(link_ipv4ll_enabled(link) && link->ipv4ll_address_configured)) {
                                 /* When DHCP or RA is enabled, at least one protocol must provide an address, or
                                  * an IPv4ll fallback address must be configured. */
                                 log_link_debug(link, "%s(): dynamic addresses or routes are not configured.", __func__);
@@ -1230,7 +1229,7 @@ static int link_acquire_ipv4_conf(Link *link) {
         assert(link->manager);
         assert(link->manager->event);
 
-        if (link_ipv4ll_enabled(link, ADDRESS_FAMILY_IPV4)) {
+        if (link_ipv4ll_enabled(link)) {
                 assert(link->ipv4ll);
 
                 log_link_debug(link, "Acquiring IPv4 link-local address");

diff --git a/src/network/networkd-link.h b/src/network/networkd-link.h
index cd541920cb85f6b6c89659ce7f12bc7bfb53184e..666ba4acf21576b842b6edfd632de9d2b1089b5a 100644 (file)
--- a/src/network/networkd-link.h
+++ b/src/network/networkd-link.h
@@ -231,7 +231,7 @@ int link_ipv6ll_gained(Link *link, const struct in6_addr *address);
 
 int link_set_mtu(Link *link, uint32_t mtu);
 
-bool link_ipv4ll_enabled(Link *link, AddressFamily mask);
+bool link_ipv4ll_enabled(Link *link);
 
 int link_stop_engines(Link *link, bool may_keep_dhcp);
 

diff --git a/src/network/networkd-network.c b/src/network/networkd-network.c
index 195bf3aaae3d16072143ce8634f6614aeb1f5a16..7ad8d087f41786ee7c77a338e7c37370b8a1f954 100644 (file)
--- a/src/network/networkd-network.c
+++ b/src/network/networkd-network.c
@@ -210,13 +210,6 @@ int network_verify(Network *network) {
         if (network->link_local < 0)
                 network->link_local = network->bridge ? ADDRESS_FAMILY_NO : ADDRESS_FAMILY_IPV6;
 
-        if (FLAGS_SET(network->link_local, ADDRESS_FAMILY_FALLBACK_IPV4) &&
-            !FLAGS_SET(network->dhcp, ADDRESS_FAMILY_IPV4)) {
-                log_warning("%s: fallback assignment of IPv4 link local address is enabled but DHCPv4 is disabled. "
-                            "Disabling the fallback assignment.", network->filename);
-                SET_FLAG(network->link_local, ADDRESS_FAMILY_FALLBACK_IPV4, false);
-        }
-
         /* IPMasquerade=yes implies IPForward=yes */
         if (network->ip_masquerade)
                 network->ip_forward |= ADDRESS_FAMILY_IPV4;

diff --git a/src/network/networkd-util.c b/src/network/networkd-util.c
index 8ddcbb2fce29d20d658aa38924e6c44983a5529b..83b38b2b0538d75fd9c1e92f2b2a03473d4d07d3 100644 (file)
--- a/src/network/networkd-util.c
+++ b/src/network/networkd-util.c
@@ -15,15 +15,6 @@ static const char* const address_family_table[_ADDRESS_FAMILY_MAX] = {
         [ADDRESS_FAMILY_IPV6]          = "ipv6",
 };
 
-static const char* const link_local_address_family_table[_ADDRESS_FAMILY_MAX] = {
-        [ADDRESS_FAMILY_NO]            = "no",
-        [ADDRESS_FAMILY_YES]           = "yes",
-        [ADDRESS_FAMILY_IPV4]          = "ipv4",
-        [ADDRESS_FAMILY_IPV6]          = "ipv6",
-        [ADDRESS_FAMILY_FALLBACK]      = "fallback",
-        [ADDRESS_FAMILY_FALLBACK_IPV4] = "ipv4-fallback",
-};
-
 static const char* const routing_policy_rule_address_family_table[_ADDRESS_FAMILY_MAX] = {
         [ADDRESS_FAMILY_YES]           = "both",
         [ADDRESS_FAMILY_IPV4]          = "ipv4",
@@ -47,7 +38,15 @@ static const char* const dhcp_lease_server_type_table[_SD_DHCP_LEASE_SERVER_TYPE
 };
 
 DEFINE_STRING_TABLE_LOOKUP_WITH_BOOLEAN(address_family, AddressFamily, ADDRESS_FAMILY_YES);
-DEFINE_STRING_TABLE_LOOKUP_WITH_BOOLEAN(link_local_address_family, AddressFamily, ADDRESS_FAMILY_YES);
+
+AddressFamily link_local_address_family_from_string(const char *s) {
+        if (streq_ptr(s, "fallback"))         /* compat name */
+                return ADDRESS_FAMILY_YES;
+        if (streq_ptr(s, "fallback-ipv4"))    /* compat name */
+                return ADDRESS_FAMILY_IPV4;
+        return address_family_from_string(s);
+}
+
 DEFINE_STRING_TABLE_LOOKUP(routing_policy_rule_address_family, AddressFamily);
 DEFINE_STRING_TABLE_LOOKUP(duplicate_address_detection_address_family, AddressFamily);
 DEFINE_CONFIG_PARSE_ENUM(config_parse_link_local_address_family, link_local_address_family,

diff --git a/src/network/networkd-util.h b/src/network/networkd-util.h
index 6100a0031ce13a5707b921d288ede334ac7e8bf4..7b48046c351ec0c546967ae816a2f2a788a4a7c1 100644 (file)
--- a/src/network/networkd-util.h
+++ b/src/network/networkd-util.h
@@ -16,8 +16,6 @@ typedef enum AddressFamily {
         ADDRESS_FAMILY_IPV4           = 1 << 0,
         ADDRESS_FAMILY_IPV6           = 1 << 1,
         ADDRESS_FAMILY_YES            = ADDRESS_FAMILY_IPV4 | ADDRESS_FAMILY_IPV6,
-        ADDRESS_FAMILY_FALLBACK_IPV4  = 1 << 2,
-        ADDRESS_FAMILY_FALLBACK       = ADDRESS_FAMILY_FALLBACK_IPV4 | ADDRESS_FAMILY_IPV6,
         _ADDRESS_FAMILY_MAX,
         _ADDRESS_FAMILY_INVALID = -1,
 } AddressFamily;
@@ -34,7 +32,6 @@ CONFIG_PARSER_PROTOTYPE(config_parse_address_family_with_kernel);
 const char *address_family_to_string(AddressFamily b) _const_;
 AddressFamily address_family_from_string(const char *s) _pure_;
 
-const char *link_local_address_family_to_string(AddressFamily b) _const_;
 AddressFamily link_local_address_family_from_string(const char *s) _pure_;
 
 const char *routing_policy_rule_address_family_to_string(AddressFamily b) _const_;

diff --git a/test/test-network/conf/dhcp-client-with-ipv4ll-fallback-with-dhcp-server.network b/test/test-network/conf/dhcp-client-with-ipv4ll-with-dhcp-server.network
similarity index 66%
rename from test/test-network/conf/dhcp-client-with-ipv4ll-fallback-with-dhcp-server.network
rename to test/test-network/conf/dhcp-client-with-ipv4ll-with-dhcp-server.network
index 9ebdbb4f8db680c816e84b8c54b27197881f34e5..0455e09b4c7be79b8285914d81d3cac91e4b76c9 100644 (file)
--- a/test/test-network/conf/dhcp-client-with-ipv4ll-fallback-with-dhcp-server.network
+++ b/test/test-network/conf/dhcp-client-with-ipv4ll-with-dhcp-server.network
@@ -3,5 +3,5 @@ Name=veth99
 
 [Network]
 DHCP=ipv4
-LinkLocalAddressing=fallback
+LinkLocalAddressing=yes
 IPv6AcceptRA=no

diff --git a/test/test-network/conf/dhcp-client-with-ipv4ll-fallback-without-dhcp-server.network b/test/test-network/conf/dhcp-client-with-ipv4ll-without-dhcp-server.network
similarity index 73%
rename from test/test-network/conf/dhcp-client-with-ipv4ll-fallback-without-dhcp-server.network
rename to test/test-network/conf/dhcp-client-with-ipv4ll-without-dhcp-server.network
index 5489c62a54e60d9a0c23c37aaef05c6914f3a3b2..2723e0a273e5459c0ac54252bd81b393b56c958a 100644 (file)
--- a/test/test-network/conf/dhcp-client-with-ipv4ll-fallback-without-dhcp-server.network
+++ b/test/test-network/conf/dhcp-client-with-ipv4ll-without-dhcp-server.network
@@ -3,7 +3,7 @@ Name=veth99
 
 [Network]
 DHCP=ipv4
-LinkLocalAddressing=fallback
+LinkLocalAddressing=yes
 IPv6AcceptRA=no
 
 [DHCPv4]

diff --git a/test/test-network/systemd-networkd-tests.py b/test/test-network/systemd-networkd-tests.py
index 688238777d8f7e414007d33462f138079d9b1249..1262611d2874987c7bdaf66b59cc75b604407b06 100755 (executable)
--- a/test/test-network/systemd-networkd-tests.py
+++ b/test/test-network/systemd-networkd-tests.py
@@ -3428,8 +3428,8 @@ class NetworkdDHCPClientTests(unittest.TestCase, Utilities):
         'dhcp-client-use-dns-yes.network',
         'dhcp-client-use-domains.network',
         'dhcp-client-vrf.network',
-        'dhcp-client-with-ipv4ll-fallback-with-dhcp-server.network',
-        'dhcp-client-with-ipv4ll-fallback-without-dhcp-server.network',
+        'dhcp-client-with-ipv4ll-with-dhcp-server.network',
+        'dhcp-client-with-ipv4ll-without-dhcp-server.network',
         'dhcp-client-with-static-address.network',
         'dhcp-client.network',
         'dhcp-server-decline.network',
@@ -3995,9 +3995,9 @@ class NetworkdDHCPClientTests(unittest.TestCase, Utilities):
         print(output)
         self.assertRegex(output, 'onlink')
 
-    def test_dhcp_client_with_ipv4ll_fallback_with_dhcp_server(self):
+    def test_dhcp_client_with_ipv4ll_with_dhcp_server(self):
         copy_unit_to_networkd_unit_path('25-veth.netdev', 'dhcp-server-veth-peer.network',
-                                        'dhcp-client-with-ipv4ll-fallback-with-dhcp-server.network')
+                                        'dhcp-client-with-ipv4ll-with-dhcp-server.network')
         start_networkd()
         self.wait_online(['veth-peer:carrier'])
         start_dnsmasq(lease_time='2m')
@@ -4032,9 +4032,9 @@ class NetworkdDHCPClientTests(unittest.TestCase, Utilities):
 
         search_words_in_dnsmasq_log('DHCPOFFER', show_all=True)
 
-    def test_dhcp_client_with_ipv4ll_fallback_without_dhcp_server(self):
+    def test_dhcp_client_with_ipv4ll_without_dhcp_server(self):
         copy_unit_to_networkd_unit_path('25-veth.netdev', 'dhcp-server-veth-peer.network',
-                                        'dhcp-client-with-ipv4ll-fallback-without-dhcp-server.network')
+                                        'dhcp-client-with-ipv4ll-without-dhcp-server.network')
         start_networkd()
         self.wait_online(['veth99:degraded', 'veth-peer:routable'])