diff --git a/src/net/udp/dhcp.c b/src/net/udp/dhcp.c index e63c3e42..3f2c451e 100644 --- a/src/net/udp/dhcp.c +++ b/src/net/udp/dhcp.c @@ -1041,10 +1041,17 @@ int dhcp_create_request ( struct dhcp_packet *dhcppkt, return rc; } - /* Add client UUID, if we have one. Required for PXE. */ + /* Add client UUID, if we have one. Required for PXE. The + * PXE spec does not specify a byte ordering for UUIDs, but + * RFC4578 suggests that it follows the EFI spec, in which the + * first three fields are little-endian. + */ client_uuid.type = DHCP_CLIENT_UUID_TYPE; if ( ( len = fetch_uuid_setting ( NULL, &uuid_setting, &client_uuid.uuid ) ) >= 0 ) { + __bswap_32s ( &client_uuid.uuid.canonical.a ); + __bswap_16s ( &client_uuid.uuid.canonical.b ); + __bswap_16s ( &client_uuid.uuid.canonical.c ); if ( ( rc = dhcppkt_store ( dhcppkt, DHCP_CLIENT_UUID, &client_uuid, sizeof ( client_uuid ) ) ) != 0 ) {