networkd: ignore Static Routes option when Classless Static Routes is given (#7807)

When the DHCP server returns both a Classless Static Routes
option and a Static Routes option, the DHCP client MUST ignore the
Static Routes option.

Closes #7792

2 files changed, 4 insertions, 0 deletions

diff --git a/src/libsystemd-network/dhcp-lease-internal.h b/src/libsystemd-network/dhcp-lease-internal.h
index ac5cc47efd..65c182f48b 100644
--- a/src/libsystemd-network/dhcp-lease-internal.h
+++ b/src/libsystemd-network/dhcp-lease-internal.h
@@ -34,6 +34,8 @@ struct sd_dhcp_route {
         struct in_addr dst_addr;
         struct in_addr gw_addr;
         unsigned char dst_prefixlen;
+
+        uint8_t option;
 };
 
 struct sd_dhcp_raw_option {
diff --git a/src/libsystemd-network/sd-dhcp-lease.c b/src/libsystemd-network/sd-dhcp-lease.c
index 78b8e058b4..2e88e39878 100644
--- a/src/libsystemd-network/sd-dhcp-lease.c
+++ b/src/libsystemd-network/sd-dhcp-lease.c
@@ -471,6 +471,7 @@ static int lease_parse_routes(
                 struct sd_dhcp_route *route = *routes + *routes_size;
                 int r;
 
+                route->option = SD_DHCP_OPTION_STATIC_ROUTE;
                 r = in4_addr_default_prefixlen((struct in_addr*) option, &route->dst_prefixlen);
                 if (r < 0) {
                         log_debug("Failed to determine destination prefix length from class based IP, ignoring");
@@ -514,6 +515,7 @@ static int lease_parse_classless_routes(
                         return -ENOMEM;
 
                 route = *routes + *routes_size;
+                route->option = SD_DHCP_OPTION_CLASSLESS_STATIC_ROUTE;
 
                 dst_octets = (*option == 0 ? 0 : ((*option - 1) / 8) + 1);
                 route->dst_prefixlen = *option;