+#define ETH_ALEN 6
+#define ETH_HLEN 14
+
+#define ETH_P_IP 0x0800 /* Internet Protocol packet */
+#define ETH_P_ARP 0x0806 /* Address Resolution packet */
+
+#define ARPOP_REQUEST 1 /* ARP request */
+#define ARPOP_REPLY 2 /* ARP reply */
+
+struct ethhdr {
+ unsigned char h_dest[ETH_ALEN]; /* destination eth addr */
+ unsigned char h_source[ETH_ALEN]; /* source ether addr */
+ unsigned short h_proto; /* packet type ID field */
+};
+
+struct arphdr {
+ unsigned short ar_hrd; /* format of hardware address */
+ unsigned short ar_pro; /* format of protocol address */
+ unsigned char ar_hln; /* length of hardware address */
+ unsigned char ar_pln; /* length of protocol address */
+ unsigned short ar_op; /* ARP opcode (command) */
+
+ /*
+ * Ethernet looks like this : This bit is variable sized however...
+ */
+ unsigned char ar_sha[ETH_ALEN]; /* sender hardware address */
+ uint32_t ar_sip; /* sender IP address */
+ unsigned char ar_tha[ETH_ALEN]; /* target hardware address */
+ uint32_t ar_tip; /* target IP address */
+} QEMU_PACKED;
+
+#define ARP_TABLE_SIZE 16
+
+typedef struct ArpTable {
+ struct arphdr table[ARP_TABLE_SIZE];
+ int next_victim;
+} ArpTable;
+
+void arp_table_add(Slirp *slirp, uint32_t ip_addr, uint8_t ethaddr[ETH_ALEN]);
+
+bool arp_table_search(Slirp *slirp, uint32_t ip_addr,
+ uint8_t out_ethaddr[ETH_ALEN]);
+
+struct Slirp {
+ QTAILQ_ENTRY(Slirp) entry;
+
+ /* virtual network configuration */
+ struct in_addr vnetwork_addr;
+ struct in_addr vnetwork_mask;
+ struct in_addr vhost_addr;
+ struct in_addr vdhcp_startaddr;
+ struct in_addr vnameserver_addr;
+
+ struct in_addr client_ipaddr;
+ char client_hostname[33];
+
+ int restricted;
+ struct ex_list *exec_list;
+
+ /* mbuf states */
+ struct mbuf m_freelist, m_usedlist;
+ int mbuf_alloced;
+
+ /* if states */
+ struct mbuf if_fastq; /* fast queue (for interactive data) */
+ struct mbuf if_batchq; /* queue for non-interactive data */
+ struct mbuf *next_m; /* pointer to next mbuf to output */
+ bool if_start_busy; /* avoid if_start recursion */
+
+ /* ip states */
+ struct ipq ipq; /* ip reass. queue */
+ uint16_t ip_id; /* ip packet ctr, for ids */
+
+ /* bootp/dhcp states */
+ BOOTPClient bootp_clients[NB_BOOTP_CLIENTS];
+ char *bootp_filename;
+ size_t vdnssearch_len;
+ uint8_t *vdnssearch;
+
+ /* tcp states */
+ struct socket tcb;
+ struct socket *tcp_last_so;
+ tcp_seq tcp_iss; /* tcp initial send seq # */
+ uint32_t tcp_now; /* for RFC 1323 timestamps */
+
+ /* udp states */
+ struct socket udb;
+ struct socket *udp_last_so;
+
+ /* icmp states */
+ struct socket icmp;
+ struct socket *icmp_last_so;
+
+ /* tftp states */
+ char *tftp_prefix;
+ struct tftp_session tftp_sessions[TFTP_SESSIONS_MAX];
+
+ ArpTable arp_table;
+
+ void *opaque;
+};
+
+extern Slirp *slirp_instance;