// // virtual Ethernet locator // // An implementation of ARP, ping(ICMP-echo) and DHCP. // Virtual host acts as a DHCP server for guest. // There are no connections between the virtual host and real ethernets. // // Virtual host IP: 192.168.10.1 // Guest IP: 192.168.10.2 // Guest netmask: 255.255.255.0 // Guest broadcast: 192.168.10.255 // #define BX_PLUGGABLE #include "iodev.h" #if BX_SUPPORT_NE2K #define LOG_THIS bx_devices.pluginNE2kDevice-> #define BX_ETH_VNET_LOGGING 1 ///////////////////////////////////////////////////////////////////////// // handler to send/receive packets ///////////////////////////////////////////////////////////////////////// static const Bit8u broadcast_macaddr[6] = {0xff,0xff,0xff,0xff,0xff,0xff}; static const Bit8u default_host_ipv4addr[4] = {192,168,10,1}; static const Bit8u subnetmask_ipv4addr[4] = {0xff,0xff,0xff,0x00}; static const Bit8u default_guest_ipv4addr[4] = {192,168,10,2}; static const Bit8u broadcast_ipv4addr[3][4] = { { 0, 0, 0, 0}, {255,255,255,255}, {192,168, 10,255}, }; #define IPPACKET_MAX 2048 #define ICMP_ECHO_PACKET_MAX 128 #define LAYER4_LISTEN_MAX 128 typedef void (*layer4_handler_t)( void *this_ptr, const Bit8u *ipheader, unsigned ipheader_len, unsigned sourceport, unsigned targetport, const Bit8u *data, unsigned data_len ); #define INET_PORT_FTPDATA 20 #define INET_PORT_FTP 21 #define INET_PORT_TIME 37 #define INET_PORT_NAME 42 #define INET_PORT_DOMAIN 53 #define INET_PORT_BOOTP_SERVER 67 #define INET_PORT_BOOTP_CLIENT 68 #define INET_PORT_HTTP 80 #define INET_PORT_NTP 123 #define BOOTREQUEST 1 #define BOOTREPLY 2 #define BOOTPOPT_PADDING 0 #define BOOTPOPT_END 255 #define BOOTPOPT_SUBNETMASK 1 #define BOOTPOPT_TIMEOFFSET 2 #define BOOTPOPT_ROUTER_OPTION 3 #define BOOTPOPT_DOMAIN_NAMESERVER 6 #define BOOTPOPT_HOST_NAME 12 #define BOOTPOPT_DOMAIN_NAME 15 #define BOOTPOPT_MAX_DATAGRAM_SIZE 22 #define BOOTPOPT_DEFAULT_IP_TTL 23 #define BOOTPOPT_BROADCAST_ADDRESS 28 #define BOOTPOPT_ARPCACHE_TIMEOUT 35 #define BOOTPOPT_DEFAULT_TCP_TTL 37 #define BOOTPOPT_NTP_SERVER 42 #define BOOTPOPT_NETBIOS_NAMESERVER 44 #define BOOTPOPT_X_FONTSERVER 48 #define BOOTPOPT_REQUESTED_IP_ADDRESS 50 #define BOOTPOPT_IP_ADDRESS_LEASE_TIME 51 #define BOOTPOPT_OPTION_OVRLOAD 52 #define BOOTPOPT_DHCP_MESSAGETYPE 53 #define BOOTPOPT_SERVER_IDENTIFIER 54 #define BOOTPOPT_PARAMETER_REQUEST_LIST 55 #define BOOTPOPT_MAX_DHCP_MESSAGE_SIZE 57 #define BOOTPOPT_RENEWAL_TIME 58 #define BOOTPOPT_REBINDING_TIME 59 #define BOOTPOPT_CLASS_IDENTIFIER 60 #define BOOTPOPT_CLIENT_IDENTIFIER 61 #define DHCPDISCOVER 1 #define DHCPOFFER 2 #define DHCPREQUEST 3 #define DHCPDECLINE 4 #define DHCPACK 5 #define DHCPNAK 6 #define DHCPRELEASE 7 class bx_vnet_pktmover_c : public eth_pktmover_c { public: bx_vnet_pktmover_c(); void pktmover_init( const char *netif, const char *macaddr, eth_rx_handler_t rxh, void *rxarg); void sendpkt(void *buf, unsigned io_len); private: void guest_to_host(const Bit8u *buf, unsigned io_len); void host_to_guest(Bit8u *buf, unsigned io_len); void process_arp(const Bit8u *buf, unsigned io_len); void host_to_guest_arp(Bit8u *buf, unsigned io_len); void process_ipv4(const Bit8u *buf, unsigned io_len); void host_to_guest_ipv4(Bit8u *buf, unsigned io_len); layer4_handler_t get_layer4_handler( unsigned ipprotocol, unsigned port); bx_bool register_layer4_handler( unsigned ipprotocol, unsigned port,layer4_handler_t func); bx_bool unregister_layer4_handler( unsigned ipprotocol, unsigned port); void process_icmpipv4( const Bit8u *ipheader, unsigned ipheader_len, const Bit8u *l4pkt, unsigned l4pkt_len); void process_tcpipv4( const Bit8u *ipheader, unsigned ipheader_len, const Bit8u *l4pkt, unsigned l4pkt_len); void process_udpipv4( const Bit8u *ipheader, unsigned ipheader_len, const Bit8u *l4pkt, unsigned l4pkt_len); void host_to_guest_udpipv4_packet( unsigned target_port, unsigned source_port, const Bit8u *udpdata, unsigned udpdata_len); void process_icmpipv4_echo( const Bit8u *ipheader, unsigned ipheader_len, const Bit8u *l4pkt, unsigned l4pkt_len); static void udpipv4_dhcp_handler( void *this_ptr, const Bit8u *ipheader, unsigned ipheader_len, unsigned sourceport, unsigned targetport, const Bit8u *data, unsigned data_len); void udpipv4_dhcp_handler_ns( const Bit8u *ipheader, unsigned ipheader_len, unsigned sourceport, unsigned targetport, const Bit8u *data, unsigned data_len); Bit8u host_macaddr[6]; Bit8u guest_macaddr[6]; Bit8u host_ipv4addr[4]; Bit8u guest_ipv4addr[4]; struct { unsigned ipprotocol; unsigned port; layer4_handler_t func; } l4data[LAYER4_LISTEN_MAX]; unsigned l4data_used; #if BX_ETH_VNET_LOGGING FILE *pktlog_txt; #endif // BX_ETH_VNET_LOGGING }; class bx_vnet_locator_c : public eth_locator_c { public: bx_vnet_locator_c(void) : eth_locator_c("vnet") {} protected: eth_pktmover_c *allocate( const char *netif, const char *macaddr, eth_rx_handler_t rxh, void *rxarg) { bx_vnet_pktmover_c *pktmover; pktmover = new bx_vnet_pktmover_c(); pktmover->pktmover_init(netif, macaddr, rxh, rxarg); return pktmover; } } bx_vnet_match; static void put_net2(Bit8u *buf,Bit16u data) { *buf = (Bit8u)(data >> 8); *(buf+1) = (Bit8u)(data & 0xff); } static void put_net4(Bit8u *buf,Bit32u data) { *buf = (Bit8u)((data >> 24) & 0xff); *(buf+1) = (Bit8u)((data >> 16) & 0xff); *(buf+2) = (Bit8u)((data >> 8) & 0xff); *(buf+3) = (Bit8u)(data & 0xff); } static Bit16u get_net2(const Bit8u *buf) { return (((Bit16u)*buf) << 8) | ((Bit16u)*(buf+1)); } static Bit32u get_net4(const Bit8u *buf) { return (((Bit32u)*buf) << 24) | (((Bit32u)*(buf+1)) << 16) | (((Bit32u)*(buf+2)) << 8) | ((Bit32u)*(buf+3)); } static Bit16u ip_checksum(const Bit8u *buf, unsigned buf_len) { Bit32u sum = 0; unsigned n; for (n = 0; n < buf_len; n++) { if (n & 1) { sum += (Bit32u)(*buf++); } else { sum += (Bit32u)(*buf++) << 8; } } while (sum > 0xffff) { sum = (sum >> 16) + (sum & 0xffff); } return (Bit16u)sum; } bx_vnet_pktmover_c::bx_vnet_pktmover_c() { } void bx_vnet_pktmover_c::pktmover_init( const char *netif, const char *macaddr, eth_rx_handler_t rxh, void *rxarg) { BX_INFO(("ne2k vnet driver")); this->rxh = rxh; this->rxarg = rxarg; memcpy(&host_macaddr[0], macaddr, 6); memcpy(&guest_macaddr[0], macaddr, 6); host_macaddr[5] = (host_macaddr[5] & (~0x01)) ^ 0x02; memcpy(&host_ipv4addr[0], &default_host_ipv4addr[0], 6); memcpy(&guest_ipv4addr[0], &broadcast_ipv4addr[0][0], 6); l4data_used = 0; register_layer4_handler(0x11,INET_PORT_BOOTP_SERVER,udpipv4_dhcp_handler); #if BX_ETH_VNET_LOGGING pktlog_txt = fopen ("ne2k-pktlog.txt", "wb"); if (!pktlog_txt) BX_PANIC (("ne2k-pktlog.txt failed")); fprintf (pktlog_txt, "vnet packetmover readable log file\n"); fprintf (pktlog_txt, "net IF = %s\n", netif); fprintf (pktlog_txt, "host MAC address = "); for (int i=0; i<6; i++) fprintf (pktlog_txt, "%02x%s", 0xff & host_macaddr[i], i<5?":" : "\n"); fprintf (pktlog_txt, "guest MAC address = "); for (int i=0; i<6; i++) fprintf (pktlog_txt, "%02x%s", 0xff & guest_macaddr[i], i<5?":" : "\n"); fprintf (pktlog_txt, "--\n"); fflush (pktlog_txt); #endif } void bx_vnet_pktmover_c::sendpkt(void *buf, unsigned io_len) { guest_to_host((const Bit8u *)buf,io_len); } void bx_vnet_pktmover_c::guest_to_host(const Bit8u *buf, unsigned io_len) { #if BX_ETH_VNET_LOGGING fprintf (pktlog_txt, "a packet from guest to host, length %u\n", io_len); Bit8u *charbuf = (Bit8u *)buf; unsigned n; for (n=0; n0) fprintf (pktlog_txt, "\n"); fprintf (pktlog_txt, "%02x ", (unsigned)charbuf[n]); } fprintf (pktlog_txt, "\n--\n"); fflush (pktlog_txt); #endif if ((io_len >= 14) && (!memcmp(&buf[6],&this->guest_macaddr[0],6)) && (!memcmp(&buf[0],&this->host_macaddr[0],6) || !memcmp(&buf[0],&broadcast_macaddr[0],6))) { switch (get_net2(&buf[12])) { case 0x0800: // IPv4. process_ipv4(buf, io_len); break; case 0x0806: // ARP. process_arp(buf, io_len); break; default: // unknown packet type. break; } } } void bx_vnet_pktmover_c::host_to_guest(Bit8u *buf, unsigned io_len) { Bit8u localbuf[60]; if (io_len < 14) { BX_PANIC(("host_to_guest: io_len < 14!")); return; } if (io_len < 60) { memcpy(&localbuf[0],&buf[0],io_len); memset(&localbuf[io_len],0,60-io_len); buf=localbuf; io_len=60; } this->rxh(this->rxarg, (void *)buf, io_len); #if BX_ETH_VNET_LOGGING fprintf (pktlog_txt, "a packet from host to guest, length %u\n", io_len); Bit8u *charbuf = (Bit8u *)buf; unsigned n; for (n=0; n0) fprintf (pktlog_txt, "\n"); fprintf (pktlog_txt, "%02x ", (unsigned)charbuf[n]); } fprintf (pktlog_txt, "\n--\n"); fflush (pktlog_txt); #endif } ///////////////////////////////////////////////////////////////////////// // ARP ///////////////////////////////////////////////////////////////////////// void bx_vnet_pktmover_c::process_arp(const Bit8u *buf, unsigned io_len) { unsigned opcode; unsigned protocol; Bit8u replybuf[60]; if (io_len < 22) return; if (io_len < (22+buf[18]*2+buf[19]*2)) return; // hardware:Ethernet if (buf[14] != 0x00 || buf[15] != 0x01 || buf[18] != 0x06) return; opcode = get_net2(&buf[20]); protocol = get_net2(&buf[16]); memset(&replybuf[0],0,60); // protocol switch (protocol) { case 0x0800: // IPv4 if (buf[19] == 0x04) { switch (opcode) { case 0x0001: // ARP REQUEST if (!memcmp(&buf[22],&this->guest_macaddr[0],6)) { memcpy(&this->guest_ipv4addr[0],&buf[28],4); if (!memcmp(&buf[38],&this->host_ipv4addr[0],4)) { memcpy(&replybuf[14],&buf[14],6); replybuf[20]=0x00; replybuf[21]=0x02; memcpy(&replybuf[22],&this->host_macaddr[0],6); memcpy(&replybuf[28],&this->host_ipv4addr[0],4); memcpy(&replybuf[32],&this->guest_macaddr[0],6); memcpy(&replybuf[38],&this->guest_ipv4addr[0],4); host_to_guest_arp(replybuf,60); } } break; case 0x0002: // ARP REPLY BX_INFO(("unexpected ARP REPLY\n")); break; case 0x0003: // RARP REQUEST BX_ERROR(("RARP is not implemented\n")); break; case 0x0004: // RARP REPLY BX_INFO(("unexpected RARP REPLY\n")); break; default: BX_INFO(("arp: unknown ARP opcode %04x",opcode)); break; } } else { BX_INFO(("arp: unknown address length %u",(unsigned)buf[19])); } break; default: BX_INFO(("arp: unknown protocol 0x%04x",protocol)); break; } } void bx_vnet_pktmover_c::host_to_guest_arp(Bit8u *buf, unsigned io_len) { memcpy(&buf[0],&this->guest_macaddr[0],6); memcpy(&buf[6],&this->host_macaddr[0],6); buf[12]=0x08; buf[13]=0x06; host_to_guest(buf,io_len); } ///////////////////////////////////////////////////////////////////////// // IPv4 ///////////////////////////////////////////////////////////////////////// void bx_vnet_pktmover_c::process_ipv4(const Bit8u *buf, unsigned io_len) { unsigned total_len; unsigned packet_id; unsigned fragment_flags; unsigned fragment_offset; unsigned ipproto; unsigned l3header_len; const Bit8u *l4pkt; unsigned l4pkt_len; if (io_len < (14U+20U)) { BX_INFO(("ip packet - too small packet\n")); return; } if ((buf[14+0] & 0xf0) != 0x40) { BX_INFO(("ipv%u packet - not implemented\n",((unsigned)buf[14+0] >> 4))); return; } l3header_len = ((unsigned)(buf[14+0] & 0x0f) << 2); if (l3header_len != 20) { BX_ERROR(("ip: option header is not implemented")); return; } if (io_len < (14U+l3header_len)) return; if (ip_checksum(&buf[14],l3header_len) != (Bit16u)0xffff) { BX_INFO(("ip: invalid checksum")); return; } total_len = get_net2(&buf[14+2]); if (io_len > (14U+total_len)) return; if (memcmp(&buf[14+16],host_ipv4addr,4) && memcmp(&buf[14+16],broadcast_ipv4addr[0],4) && memcmp(&buf[14+16],broadcast_ipv4addr[1],4) && memcmp(&buf[14+16],broadcast_ipv4addr[2],4)) { BX_INFO(("target IP address %u.%u.%u.%u is unknown", (unsigned)buf[14+16],(unsigned)buf[14+17], (unsigned)buf[14+18],(unsigned)buf[14+19])); return; } packet_id = get_net2(&buf[14+4]); fragment_flags = (unsigned)buf[14+6] >> 5; fragment_offset = ((unsigned)get_net2(&buf[14+6]) & 0x1fff) << 3; ipproto = buf[14+9]; if ((fragment_flags & 0x1) || (fragment_offset != 0)) { BX_INFO(("ignore fragmented packet!\n")); return; } else { l4pkt = &buf[14 + l3header_len]; l4pkt_len = total_len - l3header_len; } switch (ipproto) { case 0x01: // ICMP process_icmpipv4(&buf[14],l3header_len,l4pkt,l4pkt_len); break; case 0x06: // TCP process_tcpipv4(&buf[14],l3header_len,l4pkt,l4pkt_len); break; case 0x11: // UDP process_udpipv4(&buf[14],l3header_len,l4pkt,l4pkt_len); break; default: BX_INFO(("unknown IP protocol %02x\n",ipproto)); break; } } void bx_vnet_pktmover_c::host_to_guest_ipv4(Bit8u *buf, unsigned io_len) { unsigned l3header_len; memcpy(&buf[0],&this->guest_macaddr[0],6); memcpy(&buf[6],&this->host_macaddr[0],6); buf[12]=0x08; buf[13]=0x00; buf[14+0] = (buf[14+0] & 0x0f) | 0x40; l3header_len = ((unsigned)(buf[14+0] & 0x0f) << 2); memcpy(&buf[14+12],&this->host_ipv4addr[0],4); memcpy(&buf[14+16],&this->guest_ipv4addr[0],4); put_net2(&buf[14+10], 0); put_net2(&buf[14+10], ip_checksum(&buf[14],l3header_len) ^ (Bit16u)0xffff); host_to_guest(buf,io_len); } layer4_handler_t bx_vnet_pktmover_c::get_layer4_handler( unsigned ipprotocol, unsigned port) { unsigned n; for (n = 0; n < l4data_used; n++) { if (l4data[n].ipprotocol == ipprotocol && l4data[n].port == port) return l4data[n].func; } return (layer4_handler_t)NULL; } bx_bool bx_vnet_pktmover_c::register_layer4_handler( unsigned ipprotocol, unsigned port,layer4_handler_t func) { if (get_layer4_handler(ipprotocol,port) != (layer4_handler_t)NULL) { BX_INFO(("IP protocol 0x%02x port %u is already in use", ipprotocol,port)); return false; } unsigned n; for (n = 0; n < l4data_used; n++) { if (l4data[n].func == (layer4_handler_t)NULL) { break; } } if (n == l4data_used) { if (n >= LAYER4_LISTEN_MAX) { BX_ERROR(("vnet: LAYER4_LISTEN_MAX is too small")); return false; } l4data_used++; } l4data[n].ipprotocol = ipprotocol; l4data[n].port = port; l4data[n].func = func; return true; } bx_bool bx_vnet_pktmover_c::unregister_layer4_handler( unsigned ipprotocol, unsigned port) { unsigned n; for (n = 0; n < l4data_used; n++) { if (l4data[n].ipprotocol == ipprotocol && l4data[n].port == port) { l4data[n].func = (layer4_handler_t)NULL; return true; } } BX_ERROR(("IP protocol 0x%02x port %u is not registered", ipprotocol,port)); return false; } void bx_vnet_pktmover_c::process_icmpipv4( const Bit8u *ipheader, unsigned ipheader_len, const Bit8u *l4pkt, unsigned l4pkt_len) { unsigned icmptype; unsigned icmpcode; if (l4pkt_len < 8) return; icmptype = l4pkt[0]; icmpcode = l4pkt[1]; if (ip_checksum(l4pkt,l4pkt_len) != (Bit16u)0xffff) { BX_INFO(("icmp: invalid checksum")); return; } switch (icmptype) { case 0x08: // ECHO if (icmpcode == 0) { process_icmpipv4_echo(ipheader,ipheader_len,l4pkt,l4pkt_len); } break; default: BX_INFO(("unhandled icmp packet: type=%u code=%u", icmptype, icmpcode)); break; } } void bx_vnet_pktmover_c::process_tcpipv4( const Bit8u *ipheader, unsigned ipheader_len, const Bit8u *l4pkt, unsigned l4pkt_len) { if (l4pkt_len < 20) return; BX_INFO(("tcp packet - not implemented")); } void bx_vnet_pktmover_c::process_udpipv4( const Bit8u *ipheader, unsigned ipheader_len, const Bit8u *l4pkt, unsigned l4pkt_len) { unsigned udp_targetport; unsigned udp_sourceport; unsigned udp_len; layer4_handler_t func; if (l4pkt_len < 8) return; udp_sourceport = get_net2(&l4pkt[0]); udp_targetport = get_net2(&l4pkt[2]); udp_len = get_net2(&l4pkt[4]); func = get_layer4_handler(0x11,udp_targetport); if (func != (layer4_handler_t)NULL) { (*func)((void *)this,ipheader,ipheader_len, udp_sourceport,udp_targetport,&l4pkt[8],l4pkt_len-8); } else { BX_INFO(("udp - unhandled port %u",udp_targetport)); } } void bx_vnet_pktmover_c::host_to_guest_udpipv4_packet( unsigned target_port, unsigned source_port, const Bit8u *udpdata, unsigned udpdata_len) { Bit8u ipbuf[IPPACKET_MAX]; if ((udpdata_len + 42U) > IPPACKET_MAX) { BX_PANIC(("generated udp data is too long")); return; } // udp pseudo-header memcpy(&ipbuf[34U-12U],host_ipv4addr,4); memcpy(&ipbuf[34U-8U],guest_ipv4addr,4); ipbuf[34U-4U]=0; ipbuf[34U-3U]=0x11; // UDP put_net2(&ipbuf[34U-2U],8U+udpdata_len); // udp header put_net2(&ipbuf[34U+0],source_port); put_net2(&ipbuf[34U+2],target_port); put_net2(&ipbuf[34U+4],8U+udpdata_len); put_net2(&ipbuf[34U+6],0); put_net2(&ipbuf[34U+6], ip_checksum(&ipbuf[34U-12U],12U+8U+udpdata_len)); // ip header memset(&ipbuf[14U],0,20U); ipbuf[14U+0] = 0x45; ipbuf[14U+1] = 0x00; put_net2(&ipbuf[14U+2],20U+8U+udpdata_len); put_net2(&ipbuf[14U+4],1); ipbuf[14U+6] = 0x00; ipbuf[14U+7] = 0x00; ipbuf[14U+8] = 0x07; // TTL ipbuf[14U+9] = 0x11; // UDP memcpy(&ipbuf[42U],udpdata,udpdata_len); host_to_guest_ipv4(ipbuf,udpdata_len + 42U); } ///////////////////////////////////////////////////////////////////////// // ICMP/IPv4 ///////////////////////////////////////////////////////////////////////// void bx_vnet_pktmover_c::process_icmpipv4_echo( const Bit8u *ipheader, unsigned ipheader_len, const Bit8u *l4pkt, unsigned l4pkt_len) { Bit8u replybuf[ICMP_ECHO_PACKET_MAX]; if ((14U+ipheader_len+l4pkt_len) > ICMP_ECHO_PACKET_MAX) { BX_ERROR(("icmp echo: size of an echo packet is too long")); return; } memcpy(&replybuf[14],ipheader,ipheader_len); memcpy(&replybuf[14+ipheader_len],l4pkt,l4pkt_len); replybuf[14+ipheader_len+0] = 0x00; // echo reply put_net2(&replybuf[14+ipheader_len+2],0); put_net2(&replybuf[14+ipheader_len+2], ip_checksum(&replybuf[14+ipheader_len],l4pkt_len) ^ (Bit16u)0xffff); host_to_guest_ipv4(replybuf,14U+ipheader_len+l4pkt_len); } ///////////////////////////////////////////////////////////////////////// // DHCP/UDP/IPv4 ///////////////////////////////////////////////////////////////////////// void bx_vnet_pktmover_c::udpipv4_dhcp_handler( void *this_ptr, const Bit8u *ipheader, unsigned ipheader_len, unsigned sourceport, unsigned targetport, const Bit8u *data, unsigned data_len) { ((bx_vnet_pktmover_c *)this_ptr)->udpipv4_dhcp_handler_ns( ipheader,ipheader_len,sourceport,targetport,data,data_len); } void bx_vnet_pktmover_c::udpipv4_dhcp_handler_ns( const Bit8u *ipheader, unsigned ipheader_len, unsigned sourceport, unsigned targetport, const Bit8u *data, unsigned data_len) { const Bit8u *opts; unsigned opts_len; unsigned extcode; unsigned extlen; const Bit8u *extdata; unsigned dhcpmsgtype = 0; bx_bool found_serverid = false; const Bit8u *dhcpreqparams = NULL; unsigned dhcpreqparams_len = 0; Bit8u dhcpreqparam_default[8]; bx_bool dhcpreqparam_default_validflag = false; Bit8u *replyopts; Bit8u replybuf[576]; if (data_len < (236U+64U)) return; if (data[0] != BOOTREQUEST) return; if (data[1] != 1 || data[2] != 6) return; if (memcmp(&data[28U],guest_macaddr,6)) return; if (data[236] != 0x63 || data[237] != 0x82 || data[238] != 0x53 || data[239] != 0x63) return; opts = &data[240]; opts_len = data_len - 240U; while (1) { if (opts_len < 1) { BX_ERROR(("dhcp: invalid request")); return; } extcode = *opts++; opts_len--; if (extcode == BOOTPOPT_PADDING) continue; if (extcode == BOOTPOPT_END) break; if (opts_len < 1) { BX_ERROR(("dhcp: invalid request")); return; } extlen = *opts++; opts_len--; if (opts_len < extlen) { BX_ERROR(("dhcp: invalid request")); return; } extdata = opts; opts += extlen; opts_len -= extlen; switch (extcode) { case BOOTPOPT_DHCP_MESSAGETYPE: if (extlen != 1) break; dhcpmsgtype = *extdata; break; case BOOTPOPT_PARAMETER_REQUEST_LIST: if (extlen < 1) break; dhcpreqparams = extdata; dhcpreqparams_len = extlen; break; case BOOTPOPT_SERVER_IDENTIFIER: if (extlen != 4) break; if (memcmp(extdata,host_ipv4addr,4)) { BX_INFO(("dhcp: request to another server")); return; } found_serverid = true; break; default: break; } } memset(&dhcpreqparam_default,0,sizeof(dhcpreqparam_default)); memset(&replybuf[0],0,sizeof(replybuf)); replybuf[0] = BOOTREPLY; replybuf[1] = 1; replybuf[2] = 6; memcpy(&replybuf[4],&data[4],4); memcpy(&replybuf[16],default_guest_ipv4addr,4); memcpy(&replybuf[28],&data[28],6); replybuf[236] = 0x63; replybuf[237] = 0x82; replybuf[238] = 0x53; replybuf[239] = 0x63; replyopts = &replybuf[240]; opts_len = sizeof(replybuf)/sizeof(replybuf[0])-240; switch (dhcpmsgtype) { case DHCPDISCOVER: BX_INFO(("dhcp server: DHCPDISCOVER")); *replyopts ++ = BOOTPOPT_DHCP_MESSAGETYPE; *replyopts ++ = 1; *replyopts ++ = DHCPOFFER; opts_len -= 3; dhcpreqparam_default[0] = BOOTPOPT_IP_ADDRESS_LEASE_TIME; dhcpreqparam_default[1] = BOOTPOPT_SERVER_IDENTIFIER; dhcpreqparam_default_validflag = true; break; case DHCPREQUEST: BX_INFO(("dhcp server: DHCPREQUEST")); // check ciaddr. if (found_serverid || (!memcmp(&data[12],default_guest_ipv4addr,4))) { *replyopts ++ = BOOTPOPT_DHCP_MESSAGETYPE; *replyopts ++ = 1; *replyopts ++ = DHCPACK; opts_len -= 3; memcpy(guest_ipv4addr,default_guest_ipv4addr,4); dhcpreqparam_default[0] = BOOTPOPT_IP_ADDRESS_LEASE_TIME; if (!found_serverid) { dhcpreqparam_default[1] = BOOTPOPT_SERVER_IDENTIFIER; } dhcpreqparam_default_validflag = true; } else { *replyopts ++ = BOOTPOPT_DHCP_MESSAGETYPE; *replyopts ++ = 1; *replyopts ++ = DHCPNAK; opts_len -= 3; if (!found_serverid) { dhcpreqparam_default[0] = BOOTPOPT_SERVER_IDENTIFIER; dhcpreqparam_default_validflag = true; } } break; default: BX_INFO(("dhcp server: unknown message type %u",dhcpmsgtype)); return; } while (1) { while (dhcpreqparams_len-- > 0) { switch (*dhcpreqparams++) { case BOOTPOPT_SUBNETMASK: BX_INFO(("provide BOOTPOPT_SUBNETMASK")); if (opts_len < 6) { BX_ERROR(("option buffer is insufficient")); return; } opts_len -= 6; *replyopts ++ = BOOTPOPT_SUBNETMASK; *replyopts ++ = 4; memcpy(replyopts,subnetmask_ipv4addr,4); replyopts += 4; break; #if 0 // DNS is not implemented. case BOOTPOPT_DOMAIN_NAMESERVER: BX_INFO(("provide BOOTPOPT_DOMAIN_NAMESERVER")); if (opts_len < 6) { BX_ERROR(("option buffer is insufficient")); return; } opts_len -= 6; *replyopts ++ = BOOTPOPT_DOMAIN_NAMESERVER; *replyopts ++ = 4; memcpy(replyopts,host_ipv4addr,4); replyopts += 4; break; #endif case BOOTPOPT_BROADCAST_ADDRESS: BX_INFO(("provide BOOTPOPT_BROADCAST_ADDRESS")); if (opts_len < 6) { BX_ERROR(("option buffer is insufficient")); return; } opts_len -= 6; *replyopts ++ = BOOTPOPT_BROADCAST_ADDRESS; *replyopts ++ = 4; memcpy(replyopts,broadcast_ipv4addr[2],4); replyopts += 4; break; case BOOTPOPT_IP_ADDRESS_LEASE_TIME: BX_INFO(("provide BOOTPOPT_IP_ADDRESS_LEASE_TIME")); if (opts_len < 6) { BX_ERROR(("option buffer is insufficient")); return; } opts_len -= 6; *replyopts ++ = BOOTPOPT_IP_ADDRESS_LEASE_TIME; *replyopts ++ = 4; put_net4(replyopts, 900); replyopts += 4; break; case BOOTPOPT_SERVER_IDENTIFIER: BX_INFO(("provide BOOTPOPT_SERVER_IDENTIFIER")); if (opts_len < 6) { BX_ERROR(("option buffer is insufficient")); return; } opts_len -= 6; *replyopts ++ = BOOTPOPT_SERVER_IDENTIFIER; *replyopts ++ = 4; memcpy(replyopts,host_ipv4addr,4); replyopts += 4; break; case BOOTPOPT_RENEWAL_TIME: BX_INFO(("provide BOOTPOPT_RENEWAL_TIME")); if (opts_len < 6) { BX_ERROR(("option buffer is insufficient")); return; } opts_len -= 6; *replyopts ++ = BOOTPOPT_RENEWAL_TIME; *replyopts ++ = 4; put_net4(replyopts, 600); replyopts += 4; break; case BOOTPOPT_REBINDING_TIME: BX_INFO(("provide BOOTPOPT_REBINDING_TIME")); if (opts_len < 6) { BX_ERROR(("option buffer is insufficient")); return; } opts_len -= 6; *replyopts ++ = BOOTPOPT_REBINDING_TIME; *replyopts ++ = 4; put_net4(replyopts, 1800); replyopts += 4; break; default: break; } } if (!dhcpreqparam_default_validflag) break; dhcpreqparams = &dhcpreqparam_default[0]; dhcpreqparams_len = sizeof(dhcpreqparam_default); dhcpreqparam_default_validflag = false; } if (opts_len < 1) { BX_ERROR(("option buffer is insufficient")); return; } opts_len -= 2; *replyopts ++ = BOOTPOPT_END; opts_len = replyopts - &replybuf[0]; if (opts_len < (236U+64U)) { opts_len = (236U+64U); // BOOTP } if (opts_len < (548U)) { opts_len = 548U; // DHCP } host_to_guest_udpipv4_packet( sourceport, targetport, replybuf, opts_len); } #endif /* if BX_SUPPORT_NE2K */