u_short?udp_checksum（u_short?len_udp?u_long?src_addr?u_short?src_port
		?????u_long?dest_addr?u_short?dest_port?u_char?*?buff）
{
????u_short?udp_len_total?=?0;
????u_long?sum?=?0;
????u_short?pad?=?0;
????u_short?low;
????u_short?high;

????if?（len_udp?%?2?!=?0）?{
	pad?=?1;
????}
????low?=?htons（（u_short）?src_addr）;
????high?=?htons（src_addr?>>?16）;
????sum?+=?high?+?low;

????low?=?htons（（u_short）?dest_addr）;
????high?=?htons（dest_addr?>>?16）;
????sum?+=?high?+?low;

????udp_len_total?=?len_udp?+?8;
????sum?+=?IPPROTO_UDP?+?udp_len_total;
????sum?+=?udp_len_total;

????sum?+=?htons（src_port）?+?htons（dest_port）;
????for?（u_short?i?=?0;?i?	high?=?htons（*（u_short?*）?buff）;
	buff?+=?2;
	sum?+=?high;
????}
????if?（pad）?{
	sum?+=?htons（*（u_char?*）?buff）;
????}
??

?屬性????????????大小?????日期????時(shí)間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2014-05-07?10:59??sendpac\
?????文件????????1216??2013-12-14?15:12??sendpac\checksum.c
?????文件?????????198??2013-12-14?14:12??sendpac\packet.h
?????文件????????3695??2014-03-29?00:38??sendpac\sendtcp.c
?????文件????????3869??2013-12-14?14:33??sendpac\sendudp.c