sd-dhcp: check for ipv4 packets

[elogind.git] / src / libsystemd-network / dhcp-packet.c

diff --git a/src/libsystemd-network/dhcp-packet.c b/src/libsystemd-network/dhcp-packet.c
index bed942fd84345d0af51fa80dd3b9efe973408c16..3b62c2572f52608f7990b64bb20355319ca6a21a 100644 (file)
--- a/src/libsystemd-network/dhcp-packet.c
+++ b/src/libsystemd-network/dhcp-packet.c
@@ -130,6 +130,11 @@ int dhcp_packet_verify_headers(DHCPPacket *packet, size_t len, bool checksum) {
                 return -EINVAL;
         }
 
                 return -EINVAL;
         }
 

+        if (packet->ip.version != IPVERSION) {
+                log_dhcp_client(client, "ignoring packet: not IPv4");
+                return -EINVAL;
+        }
+

         if (packet->ip.ihl < 5) {
                 log_dhcp_client(client, "ignoring packet: IPv4 IHL (%u words) invalid",
                                 packet->ip.ihl);
         if (packet->ip.ihl < 5) {
                 log_dhcp_client(client, "ignoring packet: IPv4 IHL (%u words) invalid",
                                 packet->ip.ihl);


@@ -157,6 +162,11 @@ int dhcp_packet_verify_headers(DHCPPacket *packet, size_t len, bool checksum) {
 
         /* UDP */
 
 
         /* UDP */
 

+        if (packet->ip.protocol != IPPROTO_UDP) {
+                log_dhcp_client(client, "ignoring packet: not UDP");
+                return -EINVAL;
+        }
+

         if (len < DHCP_IP_UDP_SIZE) {
                 log_dhcp_client(client, "ignoring packet: packet (%zu bytes) "
                                 " smaller than IP+UDP header (%u bytes)", len,
         if (len < DHCP_IP_UDP_SIZE) {
                 log_dhcp_client(client, "ignoring packet: packet (%zu bytes) "
                                 " smaller than IP+UDP header (%u bytes)", len,