void process(NetworkInterface* ni) { Packet* packet = ni_input(ni); if(!packet) return; if(arp_process(packet)) return; Ether* ether = (Ether*)(packet->buffer + packet->start); /* if(endian16(ether->type) == ETHER_TYPE_ARP) { // ARP response ARP* arp = (ARP*)ether->payload; if(endian16(arp->operation) == 1 && endian32(arp->tpa) == address) { ether->dmac = ether->smac; ether->smac = endian48(ni->mac); arp->operation = endian16(2); arp->tha = arp->sha; arp->tpa = arp->spa; arp->sha = ether->smac; arp->spa = endian32(address); printf("- Ethernet Header -\n"); printf("Dst Mac : %012lx Src Mac : %012lx\n Ether Type : %04hx\n", endian48(ether->dmac), endian48(ether->smac), ether->type); ni_output(ni, packet); packet = NULL; } }*/ if(endian16(ether->type) == ETHER_TYPE_IPv4) { IP* ip = (IP*)ether->payload; if(ip->protocol == IP_PROTOCOL_ICMP && endian32(ip->destination) == address){ // Echo reply ICMP* icmp = (ICMP*)ip->body; // Performance check // perf(); icmp->type = 0; icmp->checksum = 0; icmp->checksum = endian16(checksum(icmp, packet->end - packet->start - ETHER_LEN - IP_LEN)); ip->destination = ip->source; ip->source = endian32(address); ip->ttl = endian8(64); ip->checksum = 0; ip->checksum = endian16(checksum(ip, ip->ihl * 4)); ether->dmac = ether->smac; ether->smac = endian48(ni->mac); ni_output(ni, packet); packet = NULL; } /* } else if(ip->protocol == IP_PROTOCOL_TCP) { TCP* tcp = (TCP*)ip->body; printf("source=%u, destination=%u, sequence=%u, acknowledgement=%u\n", endian16(tcp->source), endian16(tcp->destination), endian32(tcp->sequence), endian32(tcp->acknowledgement)); printf("offset=%d, ns=%d, cwr=%d, ece=%d, urg=%d, ack=%d, psh=%d, rst=%d, syn=%d, fin=%d\n", tcp->offset, tcp->ns, tcp->cwr, tcp->ece, tcp->urg, tcp->ack, tcp->psh, tcp->rst, tcp->syn, tcp->fin); printf("window=%d, checksum=%x, urgent=%d\n", endian16(tcp->window), endian16(tcp->checksum), endian16(tcp->urgent)); */ } if(packet) ni_free(packet); }
void process(NIC* ni) { static uint32_t myip = 0xc0a86402; // 192.168.100.2 Packet* packet = nic_input(ni); if(!packet) return; Ether* ether = (Ether*)(packet->buffer + packet->start); if(endian16(ether->type) == ETHER_TYPE_ARP) { // ARP response ARP* arp = (ARP*)ether->payload; if(endian16(arp->operation) == 1 && endian32(arp->tpa) == myip) { ether->dmac = ether->smac; ether->smac = endian48(ni->mac); arp->operation = endian16(2); arp->tha = arp->sha; arp->tpa = arp->spa; arp->sha = ether->smac; arp->spa = endian32(myip); nic_output(ni, packet); packet = NULL; } } else if(endian16(ether->type) == ETHER_TYPE_IPv4) { IP* ip = (IP*)ether->payload; if(ip->protocol == IP_PROTOCOL_ICMP && endian32(ip->destination) == myip) { // Echo reply ICMP* icmp = (ICMP*)ip->body; icmp->type = 0; icmp->checksum = 0; icmp->checksum = endian16(checksum(icmp, packet->end - packet->start - ETHER_LEN - IP_LEN)); ip->destination = ip->source; ip->source = endian32(myip); ip->ttl = endian8(64); ip->checksum = 0; ip->checksum = endian16(checksum(ip, ip->ihl * 4)); ether->dmac = ether->smac; ether->smac = endian48(ni->mac); nic_output(ni, packet); packet = NULL; } else if(ip->protocol == IP_PROTOCOL_UDP) { UDP* udp = (UDP*)ip->body; if(endian16(udp->destination) == 9000) { reply_count = 2; // Control packet uint32_t idx = 0; seq = read_u16(udp->body, &idx); user_mac = endian48(ether->smac); user_ip = endian32(ip->source); user_port = endian16(udp->source); uint8_t msg = read_u8(udp->body, &idx); switch(msg) { case 1: // MSG_CREATE { idx++; // read ctype uint32_t clen = read_u32(udp->body, &idx); char collection[clen + 1]; collection[clen] = '\0'; memcpy(collection, udp->body + idx, clen); idx += clen; uint64_t id = newID(collection); memmove(udp->body + idx + 9, udp->body + idx, endian16(udp->length) - 8 - idx); packet->end += 9; udp->length = endian16(endian16(udp->length) + 9); ip->length = endian16(endian16(ip->length) + 9); write_u8(udp->body, 4, &idx); write_u64(udp->body, id, &idx); } break; case 2: // MSG_READ reply_count = 1; break; case 3: // MSG_RETRIEVE break; case 4: // MSG_UPDATE break; case 5: // MSG_DELETE break; case 6: // MSG_HELLO reply_count = 1; break; } udp->source = endian16(9999); udp->destination = endian16(9001); udp->checksum = 0; ip->destination = ip->source; ip->source = endian32(myip); ip->ttl = endian8(ip->ttl) - 1; ip->checksum = 0; ip->checksum = endian16(checksum(ip, ip->ihl * 4)); ether->dmac = ether->smac; ether->smac = endian48(ni->mac); nic_output_dup(ni, packet); udp->destination = endian16(9002); ip->checksum = 0; ip->checksum = endian16(checksum(ip, ip->ihl * 4)); nic_output_dup(ni, packet); udp->destination = endian16(9003); ip->checksum = 0; ip->checksum = endian16(checksum(ip, ip->ihl * 4)); nic_output(ni, packet); packet = NULL; } else if(endian16(udp->destination) == 9999) { uint32_t idx = 0; uint16_t seq2 = read_u16(udp->body, &idx); if(seq == seq2 && --reply_count == 0) { udp->checksum = 0; udp->destination = endian16(user_port); udp->source = endian16(9000); ip->destination = endian32(user_ip); ip->source = endian32(myip); ip->ttl = endian8(64); ip->checksum = 0; ip->checksum = endian16(checksum(ip, ip->ihl * 4)); ether->dmac = endian48(user_mac); ether->smac = endian48(ni->mac); nic_output(ni, packet); packet = NULL; } } } } if(packet) nic_free(packet); }
void process(NetworkInterface* ni) { Packet* packet = ni_input(ni); if(!packet) return; if(arp_process(packet)) return; Ether* ether = (Ether*)(packet->buffer + packet->start); if(endian16(ether->type) == ETHER_TYPE_IPv4) { IP* ip = (IP*)ether->payload; if(ip->protocol == IP_PROTOCOL_UDP) { UDP* udp = (UDP*)ip->body; if(endian16(udp->destination) == SETKEY_PORT_NUM) { int orig_len = endian16(ip->length); Parameter* parameter = (Parameter*)udp->body; // ARP Request if(arp_request(ni, parameter->dst_ip) == true); //printf("ARP Request for destination IP\n"); int result = parse(parameter); memcpy(&(udp->body), &result, sizeof(result)); #ifdef _DEBUG_ for(int i = 0; i < 64 /* Packet Minimum Size */ - ETHER_LEN /* 14 */ - IP_LEN /* 20 */ - UDP_LEN /* 8 */ - sizeof(result); i++) udp->body[i + 4] = i; #endif uint16_t t = udp->destination; udp->destination = udp->source; udp->source = t; udp->checksum = 0; udp->length = endian16(64 - ETHER_LEN - IP_LEN); uint32_t t2 = ip->destination; ip->destination = ip->source; ip->source = t2; ip->ttl = 0x40; ip->length = endian16(64 - ETHER_LEN); ip->checksum = 0; ip->checksum = endian16(checksum(ip, ip->ihl * 4)); uint64_t t3 = ether->dmac; ether->dmac = ether->smac; ether->smac = t3; packet->end += (endian16(ip->length) - orig_len); ni_output(ni, packet); packet = NULL; } } if(ip->protocol == IP_PROTOCOL_ESP){ int orig_len = endian16(ip->length); #ifdef _DEBUG_ printf("Before Decryption - Packet : \n"); for(int i = 1; i < 1 + endian16(ip->length); i++) { printf("%02x ", ether->payload[i - 1]); // Packet - IP Header if( i % 16 == 0 ) printf("\n"); } printf("\n"); #endif if(decrypt(ip) >= 0) { packet->end += (endian16(ip->length) - orig_len); // ether->dmac = endian48(arp_get_mac(ni, endian32(ip->destination))); // ether->smac = endian48(ni->mac); #ifdef _DEBUG_ printf("- Ethernet Header After Decryption-\n"); printf("Dst Mac : %012lx Src Mac : %012lx\n Ether Type : %x\n", endian48(ether->dmac), endian48(ether->smac), ether->type); #endif if(ip->protocol == IP_PROTOCOL_ICMP){ // Echo reply ICMP* icmp = (ICMP*)ip->body; icmp->type = 0; icmp->checksum = 0; icmp->checksum = endian16(checksum(icmp, packet->end - packet->start - ETHER_LEN - IP_LEN)); uint32_t temp = ip->destination; ip->destination = ip->source; ip->source = temp; ip->ttl = endian8(64); ip->checksum = 0; ip->checksum = endian16(checksum(ip, ip->ihl * 4)); // ether->dmac = ether->smac; // ether->smac = endian48(ni->mac); // ni_output(ni, packet); // packet = NULL; } // ni_output(ni1, packet); // packet = NULL; } orig_len = endian16(ip->length); #ifdef _DEBUG_ printf("Before Encryption - Packet : \n"); for(int i = 1; i < 1 + endian16(ip->length); i++) { printf("%02x ", ether->payload[i - 1]); // Packet - IP Header if( i % 16 == 0 ) printf("\n"); } printf("\n"); #endif if(encrypt(ip) >= 0) { packet->end += (endian16(ip->length) - orig_len); ether->dmac = endian48(arp_get_mac(ni, endian32(ip->destination))); ether->smac = endian48(ni->mac); #ifdef _DEBUG_ printf("- Ethernet Header After Encryption-\n"); printf("Dst Mac : %012lx Src Mac : %012lx\n Ether Type : %x\n", endian48(ether->dmac), endian48(ether->smac), ether->type); #endif ni_output(ni, packet); packet = NULL; } } } if(packet) ni_free(packet); }