ovn-ic: Fix global blacklist filter for IPv6 addresses.

This commit fixes the prefix filter function as the return condition for
IPv6 addresses is disabling the advertisement of all learned prefixes
regardless of the match with the blacklist or not.

Reported-at: https://bugs.launchpad.net/ubuntu/+source/ovn/+bug/2046804
Fixes: 57b347c ("ovn-ic: Route advertisement.")
Signed-off-by: Roberto Bartzen Acosta <roberto.acosta@luizalabs.com>
Signed-off-by: Dumitru Ceara <dceara@redhat.com>
(cherry picked from commit 7875069)

ic/ovn-ic.c

@@ -1068,12 +1068,15 @@ prefix_is_black_listed(const struct smap *nb_options,
                 continue;
             }
         } else {
-            struct in6_addr mask = ipv6_create_mask(bl_plen);
-            for (int i = 0; i < 16 && mask.s6_addr[i] != 0; i++) {
-                if ((prefix->s6_addr[i] & mask.s6_addr[i])
-                    != (bl_prefix.s6_addr[i] & mask.s6_addr[i])) {
-                    continue;
-                }
+            struct in6_addr mask = ipv6_create_mask(plen);
+            /* First calculate the difference between bl_prefix and prefix, so
+             * use the bl mask to ensure prefixes are correctly validated.
+             * e.g.: 2005:1734:5678::/50 is a subnet of 2005:1234::/21 */
+            struct in6_addr m_prefixes = ipv6_addr_bitand(prefix, &bl_prefix);
+            struct in6_addr m_prefix = ipv6_addr_bitand(&m_prefixes, &mask);
+            struct in6_addr m_bl_prefix = ipv6_addr_bitand(&bl_prefix, &mask);
+            if (!ipv6_addr_equals(&m_prefix, &m_bl_prefix)) {
+                continue;
             }
         }
         matched = true;

tests/ovn-ic.at

@@ -1341,3 +1341,102 @@ AT_CHECK([ovn-ic-nbctl get ic_nb_global . sb_ic_cfg], [0], [dnl
 OVN_CLEANUP_IC([az1])
 AT_CLEANUP
 ])
+
+OVN_FOR_EACH_NORTHD([
+AT_SETUP([ovn-ic -- route sync -- IPv6 blacklist filter])
+AT_KEYWORDS([IPv6-route-sync-blacklist])
+
+ovn_init_ic_db
+check ovn-ic-nbctl ts-add ts1
+
+for i in 1 2; do
+    ovn_start az$i
+    ovn_as az$i
+
+    # Enable route learning at AZ level
+    check ovn-nbctl set nb_global . options:ic-route-learn=true
+    # Enable route advertising at AZ level
+    check ovn-nbctl set nb_global . options:ic-route-adv=true
+    # Enable blacklist single filter for IPv6
+    check ovn-nbctl set nb_global . options:ic-route-blacklist=" \
+            2003:db8:1::/64,2004:aaaa::/32,2005:1234::/21"
+
+    OVS_WAIT_UNTIL([ovn-nbctl show | grep ts1])
+
+    # Create LRP and connect to TS
+    check ovn-nbctl lr-add lr$i
+    check ovn-nbctl lrp-add lr$i lrp-lr$i-ts1 aa:aa:aa:aa:aa:0$i \
+            2001:db8:1::$i/64
+    check ovn-nbctl lsp-add ts1 lsp-ts1-lr$i \
+            -- lsp-set-addresses lsp-ts1-lr$i router \
+            -- lsp-set-type lsp-ts1-lr$i router \
+            -- lsp-set-options lsp-ts1-lr$i router-port=lrp-lr$i-ts1
+
+    check ovn-nbctl lrp-add lr$i lrp-lr$i-p$i 00:00:00:00:00:0$i \
+            2002:db8:1::$i/64
+
+    # Create blacklisted LRPs and connect to TS
+    check ovn-nbctl lrp-add lr$i lrp-lr$i-p-ext$i \
+            11:11:11:11:11:1$i 2003:db8:1::$i/64
+
+    check ovn-nbctl lrp-add lr$i lrp-lr$i-p-ext2$i \
+            22:22:22:22:22:2$i 2004:aaaa:bbb::$i/48
+
+    # filtered by 2005:1234::/21 - (2005:1000: - 2005:17ff:)
+    check ovn-nbctl lrp-add lr$i lrp-lr$i-p-ext3$i \
+            33:33:33:33:33:3$i 2005:1734:5678::$i/50
+
+    # additional not filtered prefix -> different subnet bits
+    check ovn-nbctl lrp-add lr$i lrp-lr$i-p-ext4$i \
+            44:44:44:44:44:4$i 2005:1834:5678::$i/50
+done
+
+for i in 1 2; do
+    OVS_WAIT_UNTIL([ovn_as az$i ovn-nbctl lr-route-list lr$i | grep learned])
+done
+
+AT_CHECK([ovn_as az1 ovn-nbctl lr-route-list lr1 |
+    awk '/learned/{print $1, $2}' ], [0], [dnl
+2002:db8:1::/64 2001:db8:1::2
+2005:1834:5678::/50 2001:db8:1::2
+])
+
+for i in 1 2; do
+    ovn_as az$i
+
+    # Drop blacklist
+    check ovn-nbctl remove nb_global . options ic-route-blacklist
+done
+
+OVS_WAIT_FOR_OUTPUT([ovn_as az1 ovn-nbctl lr-route-list lr1 |
+    awk '/learned/{print $1, $2}' | sort ], [0], [dnl
+2002:db8:1::/64 2001:db8:1::2
+2003:db8:1::/64 2001:db8:1::2
+2004:aaaa:bbb::/48 2001:db8:1::2
+2005:1734:5678::/50 2001:db8:1::2
+2005:1834:5678::/50 2001:db8:1::2
+])
+
+for i in 1 2; do
+    ovn_as az$i
+
+    check ovn-nbctl set nb_global . \
+            options:ic-route-blacklist="2003:db8:1::/64,2004:db8:1::/64"
+
+    # Create an 'extra' blacklisted LRP and connect to TS
+    check ovn-nbctl lrp-add lr$i lrp-lr$i-p-ext5$i \
+            55:55:55:55:55:5$i 2004:db8:1::$i/64
+done
+
+OVS_WAIT_FOR_OUTPUT([ovn_as az1 ovn-nbctl lr-route-list lr1 |
+    awk '/learned/{print $1, $2}' | sort ], [0], [dnl
+2002:db8:1::/64 2001:db8:1::2
+2004:aaaa:bbb::/48 2001:db8:1::2
+2005:1734:5678::/50 2001:db8:1::2
+2005:1834:5678::/50 2001:db8:1::2
+])
+
+OVN_CLEANUP_IC([az1], [az2])
+
+AT_CLEANUP
+])