libnet提供的接口函数按其作用可分为四类：
* 内存管理(分配和释放)函数
* 地址解析函数
* 数据包构造函数
* 数据包发送函数
以下分别列出这些接口函数及其功能(其参数含义简单易懂，不再解释)：
★内存管理函数
单数据包内存初始化：
int libnet_init_packet(u_short packet_size, u_char **buf);
单数据包内存释放：
void libnet_destroy_packet(u_char **buf);
多数据包内存初始化：
int libnet_init_packet_arena(struct libnet_arena **arena,u_short packet_num, u_short packet_size);
访问多数据包内存中的下一个数据包：
u_char *libnet_next_packet_from_arena(struct libnet_arena **arena,u_short packet_size);
多数据包内存释放：
void libnet_destroy_packet_arena(struct libnet_arena **arena);
★ 地址解析函数
解析主机名：
u_char *libnet_host_lookup(u_long ip, u_short use_name);
解析主机名(可重入函数)：
void libnet_host_lookup_r(u_long ip, u_short use_name, u_char *buf);
域名解析：
u_long libnet_name_resolve(u_char *ip, u_short use_name);
获取接口设备IP地址：
u_long libnet_get_ipaddr(struct libnet_link_int *l,const u_char *device, const u_char *ebuf);
获取接口设备硬件地址：
struct ether_addr *libnet_get_hwaddr(struct libnet_link_int *l,const u_char *device,const u_char *ebuf);
★ 数据包构造函数
ARP协议数据包：
int libnet_build_arp(u_short hrdw, u_short prot, u_short h_len,u_short p_len, u_short op, u_char *s_ha,
u_char *s_pa, u_char *t_ha, u_char *t_pa,const u_char *payload, int payload_len,u_char *packet_buf);
DNS协议数据包：
int libnet_build_dns(u_short id, u_short flags, u_short num_q,u_short num_answ_rr, u_short num_auth_rr,
u_short num_add_rr, const u_char * payload,int payload_len, u_char *packet_buf);
以太网协议数据包：
int libnet_build_ethernet(u_char *daddr, u_char *saddr, u_short id,const u_char *payload, int payload_len,
u_char *packet_buf);
ICMP协议数据包(ICMP_ECHO / ICMP_ECHOREPLY)：
int libnet_build_icmp_echo(u_char type, u_char code, u_short id,
u_short seq, const u_char *payload,int payload_len, u_char *packet_buf);
ICMP协议数据包(ICMP_MASKREQ / ICMP_MASKREPLY)：
int libnet_build_icmp_mask(u_char type, u_char code, u_short id,
u_short seq, u_long mask,const u_char *payload, int payload_len,
u_char *packet_buf);
ICMP协议数据包(ICMP_UNREACH)：
int libnet_build_icmp_unreach(u_char type, u_char code,
u_short orig_len, u_char orig_tos,u_short orig_id, u_short orig_frag,
u_char orig_ttl, u_char orig_prot,u_long orig_saddr, u_long orig_daddr,
const u_char *payload, int payload_len,u_char *packet_buf);
ICMP协议数据包(ICMP_TIMEXCEED)：
int libnet_build_icmp_timeexceed(u_char type, u_char code,
u_short orig_len, u_char orig_tos,u_short orig_id, u_short orig_frag,
u_char orig_ttl, u_char orig_prot,u_long orig_saddr, u_long orig_daddr,
const u_char *payload, int payload_len,u_char *packet_buf);
ICMP协议数据包(ICMP_REDIRECT)：
int libnet_build_icmp_redirect(u_char type, u_char code, u_long gateway,
u_short orig_len, u_char orig_tos,u_short orig_id, u_short orig_frag,
u_char orig_ttl, u_char orig_prot,u_long orig_saddr, u_long orig_daddr,
const u_char *payload, int payload_len,u_char *packet_buf);
ICMP协议数据包(ICMP_TSTAMP / ICMP_TSTAMPREPLY)：
int libnet_build_icmp_timestamp(u_char type, u_char code, u_short id,
u_short seq, n_time otime, n_time rtime,n_time ttime, const u_char *payload,
int payload_len, u_char *packet_buf);
IGMP协议数据包：
int libnet_build_igmp(u_char type, u_char code, u_long ip,
const u_char *payload, int payload_len,u_char *packet_buf);
IP协议数据包：
int libnet_build_ip(u_short len, u_char tos, u_short ip_id, u_short frag,u_char ttl, u_char protocol, u_long saddr, u_long daddr, const u_char *payload, int payload_len,u_char *packet_buf);
OSPF路由协议数据包：
int libnet_build_ospf(u_short len, u_char type, u_long router_id,u_long area_id, u_short auth_type,
const char *payload, int payload_s, u_char *buf);
OSPF路由协议数据包(Hello)：
int libnet_build_ospf_hello(u_long netmask, u_short interval,
u_char options, u_char priority,u_int dead_interval, u_long des_router,
u_long backup, u_long neighbor,const char *payload, int payload_s,u_char *buf);
OSPF路由协议数据包(DataBase Description (DBD))：
int libnet_build_ospf_dbd(u_short len, u_char options, u_char type,
u_int sequence_num, const char *payload,int payload_s, u_char *buf);
OSPF路由协议数据包(Link State Request (LSR))：
int libnet_build_ospf_lsr(u_int type, u_int ls_id, u_long adv_router,
const char *payload, int payload_s,u_char *buf);
OSPF路由协议数据包(Link State Update (LSU))：
int libnet_build_ospf_lsu(u_int num, const char *payload,int payload_s, u_char *buf);
OSPF路由协议数据包(Link State Acknowledgement (LSA))：
int libnet_build_ospf_lsa(u_short age, u_char options, u_char type,u_int ls_id, u_long adv_router, u_int sequence_num, u_short len,const char *payload, int payload_s,u_char *buf);
OSPF路由协议数据包(OSPF Link Sate NetworkLink State Router)：
int libnet_build_ospf_lsa_net(u_long netmask, u_int router_id,
const char *payload, int payload_s,u_char *buf);
OSPF路由协议数据包(Link State Router)：
int libnet_build_ospf_lsa_rtr(u_short flags, u_short num, u_int id,
u_int data, u_char type, u_char tos,u_short metric, const char *payload,int payload_s, u_char *buf);
OSPF路由协议数据包(Link State Summary)：
int libnet_build_ospf_lsa_sum(u_long netmask, u_int metric, u_int tos,
const char *payload, int payload_s,u_char *buf);
OSPF路由协议数据包(Link State AS External)：
int libnet_build_ospf_lsa_as(u_long netmask, u_int metric,
u_long fwd_addr, u_int tag,const char *payload, int payload_s,u_char *buf);
RIP路由协议数据包：
int libnet_build_rip(u_char cmd, u_char ver, u_short domain,
u_short addr_fam, u_short route_tag, u_long ip,u_long mask, u_long next_hop, u_long metric,
const u_char *payload, int payload_len,u_char *packet_buf);
TCP协议数据包：
int libnet_build_tcp(u_short th_sport, u_short th_dport, u_long th_seq,
u_long th_ack, u_char th_flags, u_short th_win,u_short th_urg, const u_char *payload,int payload_len, u_char *packet_buf);
UDP协议数据包：
int libnet_build_udp(u_short sport, u_short dport, const u_char *payload,int payload_len, u_char *packet_buf);
IP协议数据包选项：
int libnet_insert_ipo(struct ipoption *opt, u_char opt_len,u_char *packet_buf);
TCP协议数据包选项：
int libnet_insert_tcpo(struct tcpoption *opt, u_char opt_len,u_char *packet_buf);
★ 数据包发送函数
打开raw socket：
int libnet_open_raw_sock(int protocol);
关闭raw socket：
int libnet_close_raw_sock(int socket);
选择接口设备：
int libnet_select_device(struct sockaddr_in *sin,
u_char **device, u_char *ebuf);
打开链路层接口设备：
struct libnet_link_int *libnet_open_link_interface(char *device,char *ebuf);
关闭链路层接口设备：
int libnet_close_link_interface(struct libnet_link_int *l);
发送IP数据包：
int libnet_write_ip(int socket, u_char *packet, int packet_size);
发送链路层数据包：
int libnet_write_link_layer(struct libnet_link_int *l,const u_char *device, u_char *packet,int packet_size);
检验和计算：
int libnet_do_checksum(u_char *packet, int protocol, int packet_size);
★ 相关的支持函数
随机数种子生成器：
int libnet_seed_prand();
获取随机数：
u_long libnet_get_prand(int modulus);
16进制数据输出：
void libnet_hex_dump(u_char * buf, int len, int swap, FILE *stream);
端口列表链初始化：
int libnet_plist_chain_new(struct libnet_plist_chain **plist,char *token_list);
获取端口列表链的下一项(端口范围)：
int libnet_plist_chain_next_pair(struct libnet_plist_chain *plist,u_short *bport, u_short *eport);
端口列表链输出显示：
int libnet_plist_chain_dump(struct libnet_plist_chain *plist);
获取端口列表链：
u_char *libnet_plist_chain_dump_string(struct libnet_plist_chain *plist);
端口列表链内存释放：
void libnet_plist_chain_free(struct libnet_plist_chain *plist);