/* ***************************************************
* Function: send_syn_ack
* ***************************************************
* Passive node calls this to send SYN_ACK and wait for
* the final ACK packet. It tries a total of 6 times before
* giving up.
*/
static bool send_syn_ack(mysocket_t sd, context_t *ctx, struct tcphdr* syn_packet)
{
struct tcphdr* ack_packet = (struct tcphdr *)calloc(1,(TH_MAX_OFFSET*sizeof(uint32_t))+STCP_MSS);
unsigned int event;
bool success = false;
int num_tries = 1;
struct timeval tstart;
gettimeofday(&tstart, NULL); /*Start the timer */
network_send(sd, syn_packet, (TH_MIN_OFFSET*sizeof(uint32_t)));
while((num_tries < MAX_RT_TRIES) && !success){
event = wait_for_event(sd, NETWORK_DATA, ctx, tstart);
if (event & NETWORK_DATA) {
network_recv(sd, ack_packet);
our_dprintf("Passive (ACK waiting): Ack: %d, Seq:%d, Next Seq:%d, Last Ack Sent: %d\n",
ack_packet->th_ack, ack_packet->th_seq, ctx->nxt_seq_num, ctx->last_ack_sent);
success = ((ack_packet->th_flags == TH_ACK) &&
(ack_packet->th_ack == ctx->nxt_seq_num));
}
else if (event==TIMEOUT){
our_dprintf("Passive Final INIT ACK not Received TIMEOUT!\n");
num_tries+=1;
gettimeofday(&tstart, NULL);
our_dprintf("PASSIVE - SEND SYN_ACK Packet with seq: %d and ack: %d \n",
syn_packet->th_seq, syn_packet->th_ack);
network_send(sd, syn_packet, (TH_MIN_OFFSET*sizeof(uint32_t)));
}
}
if (success){
our_dprintf("PASSIVE - RCVD Last Ack Packet has seq: %d and ack: %d \n",
ack_packet->th_seq, ack_packet->th_ack);
ctx->recv_win = MIN(syn_packet->th_win, CWIN);
}
free(ack_packet);
return success;
}
/* ***************************************************
* Function: passive_init
* ***************************************************
* Passive node waits for a SYN packet to arrive, it then
* sends an SYN_ACK using another helper function (below)
*/
static bool passive_init(mysocket_t sd, context_t *ctx)
{
ctx->connection_state = CSTATE_LISTEN;
struct tcphdr* syn_packet = (struct tcphdr *)calloc(1,
(TH_MAX_OFFSET*sizeof(uint32_t))+STCP_MSS);
/* Listen for a connection request */
while (true){
stcp_wait_for_event(sd, NETWORK_DATA, NULL);
network_recv(sd, syn_packet);
if (syn_packet->th_flags == TH_SYN){
break;
}
}
our_dprintf("PASSIVE - RCVD SYN with seq: %d\n", syn_packet->th_seq);
/* Prepare SYN_ACK*/
syn_packet->th_ack = syn_packet->th_seq + 1;
syn_packet->th_seq = ctx->initial_sequence_num;
syn_packet->th_off = TH_MIN_OFFSET;
syn_packet->th_flags = TH_SYN | TH_ACK;
syn_packet->th_win = RWIN;
/*Update connection state variables */
ctx->last_ack_sent = syn_packet->th_ack;
ctx->nxt_seq_num = ctx->initial_sequence_num + 1;
ctx->connection_state = CSTATE_SYN_RCVD;
ctx->seq_base = ctx->nxt_seq_num;
our_dprintf("PASSIVE - SEND SYN_ACK Packet with seq: %d and ack: %d \n",
syn_packet->th_seq, syn_packet->th_ack);
bool success = send_syn_ack(sd, ctx, syn_packet);
free(syn_packet);
return success;
}
static ssize_t read_all(void *dst, size_t len, int fd)
{
uintptr_t ptr = (uintptr_t) dst;
while (len) {
ssize_t ret = network_recv(fd, (void *) ptr, len, 0);
if (ret < 0)
return ret;
ptr += ret;
len -= ret;
}
return (ssize_t)(ptr - (uintptr_t) dst);
}
static ssize_t network_read_line(struct iio_context_pdata *pdata,
int desc, char *dst, size_t len)
{
size_t i;
#ifdef __linux__
ssize_t ret;
ret = network_recv(desc, dst, len, MSG_PEEK);
if (ret < 0)
return ret;
/* Lookup for the trailing \n */
for (i = 0; i < (size_t) ret && dst[i] != '\n'; i++);
/* No \n found? Just garbage data */
if (i == (size_t) ret)
return -EIO;
/* Advance the read offset to the byte following the \n */
return network_recv(desc, dst, i + 1, MSG_TRUNC);
#else
bool found = false;
for (i = 0; i < len - 1; i++) {
ssize_t ret = network_read_data(pdata, desc, dst + i, 1);
if (ret < 0)
return ret;
if (dst[i] != '\n')
found = true;
else if (found)
break;
}
dst[i] = '\0';
return (ssize_t) i;
#endif
}
gpointer
network_reciever(gpointer data)
{
char *buffer;
unsigned int level;
sys_queue = g_async_queue_new();
msg_queue = g_async_queue_new();
pthread_detach(pthread_self());
while (1) {
if (network_recv(&level, (void **)buffer, security->session) < 1)
break;
if (level == PACKET_SYS)
g_async_queue_push(sys_queue, buffer);
else if (level == PACKET_MSG)
g_async_queue_push(msg_queue, buffer);
else
printf("Cannot specify target for packet(not sys and msg).\n");
}
}
void NetworkWorker::run()
{
while (true)
{
{
Glib::Threads::Mutex::Lock lock(m_mutex);
if (m_network.disconnected)
break;
network_set_fds(&m_network);
m_network.tv.tv_sec = 1;
m_network.tv.tv_usec = 0;
}
network_select(&m_network);
{
Glib::Threads::Mutex::Lock lock(m_mutex);
network_recv(&m_network);
network_send(&m_network);
m_stop = m_network.disconnected;
if (m_network.has_data_in)
{
std::string data(m_network.buf_in);
m_network.buf_in[0] = 0;
m_network.has_data_in = FALSE;
int pos;
while ((pos = data.find("\r\n")) != std::string::npos)
{
m_in_data.push(data.substr(0, pos));
data = data.substr(pos + 2);
}
strcpy(m_network.buf_in, data.c_str());
strcat(m_network.buf_in, "\0");
if (strlen(m_network.buf_in) > 0)
m_network.has_data_in = TRUE;
}
}
{
Glib::Threads::Mutex::Lock lock(m_mutex);
m_dispatcher.emit();
}
}
}
/* ***************************************************
* Function: sendrcv_syn
* ***************************************************
* Helper function for active-side network initiation.
* It sends the SYN packet and waits for the right SYN_ACK
*/
static bool sendrcv_syn(mysocket_t sd, context_t *ctx, struct tcphdr* in_packet)
{
/* Set SYN Headers */
struct tcphdr* out_packet = (struct tcphdr *)calloc(1,(TH_MIN_OFFSET*sizeof(uint32_t)));
out_packet->th_ack = 0;
out_packet->th_seq = ctx->initial_sequence_num;
out_packet->th_flags = TH_SYN;
out_packet->th_off = TH_MIN_OFFSET;
out_packet->th_win = RWIN;
ctx->nxt_seq_num = ctx->initial_sequence_num + 1; /* SYN Packet = 1 byte */
our_dprintf("Active Sending SYN. Seq:%d\n", out_packet->th_seq);
unsigned int event;
bool success = false;
int num_tries = 1;
struct timeval tstart;
gettimeofday(&tstart,NULL); /*start the timer */
network_send(sd, out_packet, (TH_MIN_OFFSET*sizeof(uint32_t)));
/* Try sending the SYN a total of 6 times before giving up */
while ((num_tries < MAX_RT_TRIES) && !success){
event = wait_for_event(sd, NETWORK_DATA, ctx, tstart);
if (event & NETWORK_DATA) {
network_recv(sd, in_packet);
/* Check to see if we got the right SYN_ACK */
success = ((in_packet->th_flags & (TH_SYN | TH_ACK)) &&
(in_packet->th_ack == ctx->nxt_seq_num));
}
else if (event==TIMEOUT){
our_dprintf("Active - SYN TIMEOUT!, no SYN_ACK!\n");
gettimeofday(&tstart,NULL);
num_tries+=1;
our_dprintf("Active Resending SYN. Seq:%d\n", out_packet->th_seq);
network_send(sd, out_packet, (TH_MIN_OFFSET*sizeof(uint32_t)));
}
}
free(out_packet);
return success;
}
/* ***************************************************
* Function: handle_network_data
* ***************************************************
* A packet has arrived. If its an ACK packet, call a helper
* function that deals with acks. If the packet has data or it's
* a FIN packet, then add the packet to the receiver buffer only
* if it fits in the receiving window. If it doesn't fit,
* drop the packet. If it fits, send an acknowledgement.
*/
static void handle_network_data(mysocket_t sd, context_t *ctx)
{
char *pkt = (char *)calloc(1, (TH_MAX_OFFSET*sizeof(uint32_t)) + STCP_MSS);
size_t total_length = network_recv(sd, pkt);
struct tcphdr* hdr = (struct tcphdr *)pkt;
ctx->recv_win = MIN(hdr->th_win, CWIN);
if (hdr->th_flags & TH_ACK) {
handle_ack(hdr, sd, ctx);
}
size_t data_length = total_length - TCP_DATA_START(hdr);
if (data_length>0 || (hdr->th_flags & TH_FIN)) {
our_dprintf("Received %d bytes of data with seq: %d, last ack sent: %d\n",
data_length, hdr->th_seq, ctx->last_ack_sent);
/* Does the packet fit in the receiving window?*/
if ((hdr->th_seq + data_length)<=(ctx->last_ack_sent + RWIN)) {
add_to_recv_buffer(ctx, pkt, total_length);
if (hdr->th_seq == ctx->last_ack_sent){
/* The packet arrived in order. We can remove all in-order
* packets from the receive buffer now */
our_dprintf("Packet In Order. Handling buffer\n");
handle_recv_buffer(sd, ctx);
}
else {
if (hdr->th_seq > ctx->last_ack_sent) {
our_dprintf("This packet is out of order. Adding to recv buffer\n");
}
}
send_ack(sd, ctx);
}
else {
our_dprintf("Packet outside receiver buffer. Dropping!!!\n");
}
}
free(pkt);
}
/**
* Thread processing network events (coming from other nodes).
*
* This routine may set the network status to down as a side-effect
* of calling network_recv(), and sets said status to up when the
* network comes back.
*
* \param[in] dummy Unused
*
* \return NULL
*/
static void
net_events_routine(void *dummy)
{
int dest_mbox;
ExamsgMID mid;
size_t size;
char *msg;
int s;
exalog_as(EXAMSG_CMSGD_ID);
exalog_trace("network events routine started");
while (!quit)
{
int status = network_status();
bool retry;
if (status == -ENETDOWN)
{
network_waitup();
network_set_status(0);
}
do
{
s = network_recv(net_mh, &mid, &msg, &size, &dest_mbox);
retry = (s < 0 && network_manageable(s) && s != -ENETDOWN);
if (retry)
os_sleep(1);
}
while (retry);
/* Succeeded, the network status is ok */
if (s > 0 && status != 0)
network_set_status(0);
if (s == 0 || s == -ENETDOWN)
continue;
EXA_ASSERT(s > 0);
/* Ping from another node for keepalive */
if (((ExamsgAny *)msg)->type == EXAMSG_PING)
{
EXA_ASSERT(dest_mbox == EXAMSG_CMSGD_ID);
exalog_trace("received an EXAMSG_PING from %u:%s",
mid.netid.node, mid.host);
continue;
}
exalog_trace("delivering %" PRIzu " bytes to %d",
size, dest_mbox);
s = examsgMboxSend(&mid, examsgOwner(net_mh), dest_mbox, msg, size);
switch (s)
{
case -ENXIO:
/* The mailbox does not exist (yet). This is not an error: csupd may
* not be started yet and we receive an examsg for it.
* XXX Doesn't sound too good to me, and we should at least check that
* the destination is indeed csupd */
break;
case -ENOSPC:
mailbox_full(dest_mbox, &mid, (Examsg *)msg);
break;
default:
EXA_ASSERT_VERBOSE(s == size + sizeof(mid),
"Error %d delivering message to %d",
s, dest_mbox);
break;
}
}
}
static void client_console(int sock)
{
char client_buf[BABBLE_BUFFER_SIZE];
char *server_buf;
char *user_buf =NULL;
size_t user_buf_size=0;
int cid = -1;
int answer_expected = 0;
while(getline(&user_buf, &user_buf_size, stdin) != -1){
/* truncate input if need be */
strncpy(client_buf, user_buf, BABBLE_BUFFER_SIZE);
str_clean(client_buf);
/* check command on client side */
cid = str_to_command(client_buf, &answer_expected);
if(cid == -1){
continue;
}
if (network_send(sock, strlen(client_buf)+1,(void*) client_buf) != strlen(client_buf)+1){
perror("ERROR writing to socket");
break;
}
if(cid == TIMELINE){
/* specific protocol for timeline request */
int *t_length, i;
if(network_recv(sock, (void**) &t_length) != sizeof(int)){
perror("ERROR in timeline protocol");
break;
}
printf("Timeline of size: %d\n", *t_length);
/* recv only the last BABBLE_TIMELINE_MAX */
int to_recv= (*t_length < BABBLE_TIMELINE_MAX)? *t_length : BABBLE_TIMELINE_MAX;
free(t_length);
for(i=0; i< to_recv; i++){
if(network_recv(sock, (void**) &server_buf) < 0){
perror("ERROR reading from socket");
break;
}
printf("%s", server_buf);
free(server_buf);
}
if(i != to_recv){
break;
}
}
else{
if(answer_expected){
if(network_recv(sock, (void**) &server_buf) < 0){
perror("ERROR reading from socket");
break;
}
printf("%s", server_buf);
free(server_buf);
}
}
}
printf("### Client exiting \n");
}
static ssize_t network_read_data(struct iio_context_pdata *pdata,
int desc, char *dst, size_t len)
{
return network_recv(desc, dst, len, 0);
}
