static void dns_send(void)
{
struct header *header;
int n, name_len;
uchar *p, *pkt;
const char *s;
const char *name;
enum dns_query_type qtype = DNS_A_RECORD;
name = net_dns_resolve;
pkt = (uchar *)(net_tx_packet + net_eth_hdr_size() + IP_UDP_HDR_SIZE);
p = pkt;
/* Prepare DNS packet header */
header = (struct header *)pkt;
header->tid = 1;
header->flags = htons(0x100); /* standard query */
header->nqueries = htons(1); /* Just one query */
header->nanswers = 0;
header->nauth = 0;
header->nother = 0;
/* Encode DNS name */
name_len = strlen(name);
p = (uchar *)&header->data; /* For encoding host name into packet */
do {
s = strchr(name, '.');
if (!s)
s = name + name_len;
n = s - name; /* Chunk length */
*p++ = n; /* Copy length */
memcpy(p, name, n); /* Copy chunk */
p += n;
if (*s == '.')
n++;
name += n;
name_len -= n;
} while (*s != '\0');
*p++ = 0; /* Mark end of host name */
*p++ = 0; /* Some servers require double null */
*p++ = (unsigned char) qtype; /* Query Type */
*p++ = 0;
*p++ = 1; /* Class: inet, 0x0001 */
n = p - pkt; /* Total packet length */
debug("Packet size %d\n", n);
dns_our_port = random_port();
net_send_udp_packet(net_server_ethaddr, net_dns_server,
DNS_SERVICE_PORT, dns_our_port, n);
debug("DNS packet sent\n");
}
struct p2p *p2p_init(const char *rpc_srv, const char *stun_srv)
{
char ip[64];
struct skt_addr tmpaddr;
static stun_addr _mapped;
struct p2p *p2p = CALLOC(1, struct p2p);
if (!p2p) {
loge("malloc failed: %d\n", errno);
return NULL;
}
p2p->rpc = rpc_create(rpc_srv, _rpc_port);
if (!p2p->rpc) {
loge("rpc_create failed\n");
return NULL;
}
RPC_REGISTER_MSG_MAP(BASIC_RPC_API_RESP);
rpc_set_cb(p2p->rpc, on_rpc_read, on_rpc_write, on_rpc_error, p2p);
skt_getaddr_by_fd(p2p->rpc->fd, &tmpaddr);
skt_addr_ntop(_local_ip, tmpaddr.ip);
//_local_port = tmpaddr.port;
//logi("_local_port = %d\n", _local_port);
stun_init(stun_srv);
p2p->nat.type = stun_nat_type();
p2p->nat.uuid = p2p->rpc->send_pkt.header.uuid_src;
p2p->nat.local.ip = skt_addr_pton(_local_ip);
_local_port = random_port();
p2p->nat.local.port = _local_port;
p2p->nat.fd = stun_socket(_local_ip, _local_port, &_mapped);
_mapped.addr = ntohl(_mapped.addr);
skt_addr_ntop(ip, _mapped.addr);
p2p->nat.reflect.ip = _mapped.addr;
p2p->nat.reflect.port = _mapped.port;
logi("get nat info from local\n");
logi("nat.type = %d\n", p2p->nat.type);
logi("nat.local_addr %s:%d\n", _local_ip, p2p->nat.local.port);
logi("nat.reflect_addr %s:%d\n", ip, p2p->nat.reflect.port);
p2p->rpc_state = P2P_RPC_INIT;
_p2p = p2p;
return p2p;
}
/**
* This is the main function of the program that handles calling other
* functions to implemented the needed operations of the replay functionaily.
*/
int
main(int argc, char **argv)
{
unsigned int k;
unsigned int num_packets=0;
char port_mode[10]; /* does user specify random port generation?*/
char random_strg[7] = "random";
char* iface = argv[1];
char* new_rmac_ptr;
char* new_rip_ptr;
in_addr new_remoteip;
struct mac_addr new_remotemac;
in_addr myip;
struct mac_addr mymac;
/*temporary packet buffers*/
unsigned int new_src_port = 0;
unsigned int retransmissions = 0;
pcap_t *local_handle;
char errbuf[PCAP_ERRBUF_SIZE];
char ebuf[SENDPACKET_ERRBUF_SIZE];
optionProcess(&tcpliveplayOptions, argc, argv); /*Process AutoOpts for manpage options*/
if((argc < 5) || (argv[1]==NULL) || (argv[2]==NULL) || (argv[3]==NULL) || (argv[4]==NULL) || (argv[5]==NULL)) {
printf("ERROR: Incorrect Usage!\n");
printf("Usage: tcpliveplay <eth0/eth1> <file.pcap> <Destinatin IP [1.2.3.4]> <Destination mac [0a:1b:2c:3d:4e:5f]> <specify 'random' or specific port#>\n");
printf("Example:\n yhsiam@yhsiam-VirtualBox:~$ sudo tcpliveplay eth0 test1.pcap 192.168.1.4 52:57:01:11:31:92 random\n\n");
exit(0);
}
iface_addrs(iface, &myip, &mymac); /* Extract MAC of interface replay is being request on */
/* open send function socket*/
if ((sp = sendpacket_open(iface, ebuf, TCPR_DIR_C2S, SP_TYPE_NONE)) == NULL)
errx(-1, "Can't open %s: %s", argv[1], ebuf);
/* random dport vs. specified dport operation*/
strcpy(port_mode, argv[5]);
/*for(int i = 0; i<10; i++) tolower(port_mode[i]);*/
if(strcmp(port_mode, random_strg)==0) {
new_src_port = random_port();
} else new_src_port = atoi(argv[5]);
/*else {
printf("Port specification error. Please specify 'random' for random source port generation between 49152 and 65535 OR specifiy a specific source port number.\n");
return;
}*/
printf("new source port:: %d\n", new_src_port);
/* Establish a handler for SIGALRM signals. */
/* This is used as timeout for unresponsive remote hosts */
signal (SIGALRM, catch_alarm);
/* Extract new Remote MAC & IP inputted at command line */
new_rmac_ptr= argv[4];
new_rip_ptr = argv[3];
/* These function setup the MAC & IP addresses in the mac_addr & in_addr structs */
extmac(new_rmac_ptr, &new_remotemac);
extip(new_rip_ptr, &new_remoteip);
/* Rewrites the given "*.pcap" file with all the new parameters and returns the number of packets */
/* that need to be replayed */
num_packets = rewrite(&new_remoteip, &new_remotemac, &myip, &mymac, argv[2], new_src_port);
/* create schedule & set it up */
sched = (struct tcp_sched*) malloc(num_packets*sizeof(struct tcp_sched));
pkts_scheduled = setup_sched(sched); /* Returns number of packets in schedule*/
/* Set up the schedule struct to be relative numbers rather than absolute*/
relative_sched(sched, sched[1].exp_rseq, num_packets);
printf("Packets Scheduled %d\n", pkts_scheduled);
/* Open socket for savedfile traffic to be sent*/
local_handle = pcap_open_offline("newfile.pcap", errbuf); /*call pcap library function*/
if (local_handle == NULL) {
fprintf(stderr,"Couldn't open pcap file %s: %s\n", "newfile.pcap", errbuf);
return(2);
}
/* Open socket for live traffic to be listed to*/
live_handle = set_live_filter(iface, &myip, new_src_port); /* returns a pcap_t that filters out traffic other than TCP*/
if (live_handle == NULL) {
fprintf(stderr,"Error occured while listing on traffic: %s\n", errbuf);
return(2);
}
/* Printout when no packets are scheduled */
if(pkts_scheduled==0) {
printf("\n+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n");
printf("+ ERROR:: There are no TCP packets to sent +\n");
printf("+ Closing replay... +\n");
printf("+ Thank you for Playing, Play again! +\n");
printf("+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n\n");
return ERROR;
}
/* Start replay by sending the first packet, the SYN, from the schedule */
else if(sched[0].local) { /* Send first packet*/
sendpacket(sp, sched[sched_index].packet_ptr, sched[sched_index].pkthdr.len, &sched[sched_index].pkthdr);
printf("Sending Local Packet............... [%d]\n",sched_index+1);
sched_index++; /* Proceed in the schedule */
}
/* Main while loop that handles the decision making and the replay oprations */
while(sched_index<pkts_scheduled) {
if(!keep_going) { /*Check the timeout variable */
printf("\n======================================================================\n");
printf("= TIMEOUT:: Remote host is not responding. You may have crashed =\n");
printf("= the host you replayed these packets against OR the packet sequence =\n");
printf("= changed since the capture was taken resulting in differing =\n");
printf("= expectations. Closing replay... =\n");
printf("======================================================================\n\n");
break;
}
/* tcphdr_rprev carries the last remote tcp header */
if(tcphdr_rprev == NULL) {
//printf("FIRST PASS!\n");
}
/* Check if received RST or RST-ACK flagged packets*/
else if((tcphdr_rprev->th_flags==TH_RST) || (tcphdr_rprev->th_flags==(TH_RST|TH_ACK))) {
printf("\n++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n");
printf("+ ERROR:: Remote host has requested to RESET the connection. +\n");
printf("+ Closing replay... +\n");
printf("++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n\n");
break;
}
/*Check if received earlier FIN-ACK than expected
else if((sched_index-1 < finack_rindex) && (tcphdr_rprev->th_flags==(TH_FIN|TH_ACK))){
printf("\n++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n");
printf("+ ERROR:: Remote host sent an earlier FIN-ACK than expected. +\n");
printf("+ Closing replay... +\n");
printf("++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n\n");
return;
} */
/* Do the following if we receive a packet that ACKs for the same ACKing of next packet */
else if((tcphdr_rprev->th_seq==htonl(sched[sched_index].exp_rseq)) && (tcphdr_rprev->th_ack==htonl(sched[sched_index].exp_rack)) && (size_payload_prev>0)) {
printf("Received Remote Packet............... [%d]\n",sched_index+1);
printf("Skipping Packet...................... [%d] to Packet [%d]\n",sched_index+1, sched_index+2);
printf("Next Remote Packet Expectation met.\nProceeding in replay...\n");
sched_index++;
}
/* Do the following if payload does not meet expectation and re-attempt with the remote host for 3 tries*/
else if(different_payload) {
printf("\n+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n");
printf("+ WARNING: Remote host is not meeting packet size expectations. +\n");
printf("+ for packet %-d. Application layer data differs from capture being replayed. +\n", diff_payload_index+1);
printf("+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n\n");
printf("Requesting retransmission.\n Proceeding...\n");
different_payload = false;
}
/* Local Packets */
if(sched[sched_index].local) {
/*Reset alarm timeout*/
alarm (ALARM_TIMEOUT);
printf("Sending Local Packet............... [%d]\n",sched_index+1);
/* edit each packet tcphdr before sending based on the schedule*/
if(sched_index>0) {
sched[sched_index].tcphdr->th_ack = htonl(sched[sched_index].curr_lack);
fix_all_checksum_liveplay(sched[sched_index].iphdr);
}
/* If 3 attempts of resending was made, then error out to the user */
if(sched[sched_index].sent_counter==3) {
printf("\n++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n");
printf("+ ERROR: Re-sent packet [%-d] 3 times, but remote host is not +\n", sched_index+1);
printf("+ responding as expected. 3 resend attempts are a maximum. +\n");
printf("+ Closing replay... +\n");
printf("++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n\n");
break;
}
/* If nothing goes wrong, then send the packet scheduled to be sent, then proceed in the schedule */
sendpacket(sp, sched[sched_index].packet_ptr, sched[sched_index].pkthdr.len, &sched[sched_index].pkthdr);
sched[sched_index].sent_counter++; /* Keep track of how many times this specific packet was attempted */
sched_index++; /* proceed */
}
/* Remote Packets */
else if(sched[sched_index].remote) {
alarm (ALARM_TIMEOUT);
printf("Receiving Packets from remote host...\n");
pcap_dispatch(live_handle, 1, got_packet, NULL); /* Listen in on NIC for tcp packets */
//printf("pcap_loop returned\n");
}
} /* end of main while loop*/
pcap_breakloop(live_handle);
pcap_close(live_handle);
sendpacket_close(sp); /* Close Send socket*/
remove("newfile.pcap"); /* Remote the rewritten file that was created*/
for(k=0; k<pkts_scheduled; k++) {
retransmissions+=sched[k].sent_counter;
}
/* User Debug Result Printouts*/
if(sched_index==pkts_scheduled) {
printf("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n");
printf("~ CONGRATS!!! You have successfully Replayed your pcap file '%s' \n", argv[2]);
printf("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n\n");
}
else {
printf("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n");
printf("~ Unfortunately an error has occurred halting the replay of \n");
printf("~ the pcap file '%s'. Please see error above for details... \n", argv[2]);
printf("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n\n");
}
printf("----------------TCP Live Play Summary----------------\n");
printf("- Packets Scheduled to be Sent & Received: %-d \n", pkts_scheduled);
printf("- Actual Packets Sent & Received: %-d \n", sched_index);
printf("- Total Local Packet Re-Transmissions due to packet \n");
printf("- loss and/or differing payload size than expected: %-d \n", retransmissions);
printf("- Thank you for Playing, Play again! \n");
printf("----------------------------------------------------------\n\n");
return 0;
}
